Deaf reading reaction number 2 Coursework Example | Topics and Well Written Essays - 250 words

Deaf reading reaction number 2 - Coursework Example Ideas such as this stand out to me and are in line with my beliefs no bias should exist in the provision of education. My knowledge in this area reveals that the most urgent need of the deaf children is the urge for communication. However, these are always hampered if the child does not receive ample guidance and understanding from the teachers and fellow children. This fact is as well brought out in the article. Therefore, any setting which fails to meet the communication and related needs of a deaf child should be avoided. I’ve also understood better that it is the responsibility of everyone to enhance this success in the education of our deaf children. There should be a shared responsibility between the state and the community in which the child lives to help them acquire education. All of us must be accountable for the educational achievement and inclusion of all deaf children into the education system for their benefit (Cerney

Legal and Ethical Implications for Classroom Management Essay Example for Free

Legal and Ethical Implications for Classroom Management Essay Today’s classrooms are more dynamic than ever before. Educational needs of students are changing at breakneck speeds, along with the demands being placed on their teachers. There are associated legal and ethical implications that are evolving as rapidly as the technology that is driving a lot of the change. In order to have a chance to meet the needs of students and legal/ethical obligations, educators must have well developed classroom management techniques. These can get tricky quite often and require balancing the increasingly diverse needs of many different people. To be an effective teacher today is extremely difficult for these reasons. This essay will examine some of the current issues that teachers are exposed to in today’s classrooms by summarizing four journal articles and responding to them. The specific issues will be free speech and what it means in a school setting, cell phones in classrooms, bullying (specifically of students with disabilities), and gender specific dress codes. Freedom of Speech The issue addressed in the first article summary is freedom of speech and how it is interpreted in a public school setting in relation to the distribution of religious materials. This is really not a new topic of debate. Current precedents have been set in court cases dating as far back as1969 and the Tinker vs. Desmoines case. In that case, the court decision reads that, in order to prohibit any students’ expression of opinion, the school must provide evidence to support the fact that the actions being suppressed would be significantly disruptive (Essex, 2006). Because it is an issue of ongoing debate there are cases still being heard all over the country. This article is specifically in response to a case in the New York Supreme Court, where a student was prohibited from distributing religious fliers on school property. The question is, why was the student prevented from expressing her opinion in the first place. According to Essex (2006), one of the requirements placed on schools is that they remain viewpoint neutral. This means that if the literature was suppressed because it was religious in nature, the suppression violated her First Amendment rights, even in the school setting. In all court cases, the real message has been that schools are responsible for making sure parents and students are aware that the schools are merely sending messages indiscriminately from religious and non-secular sources and that they are not in support of any of them (Essex, 2006). Really the essence of the article is that sound policies must be in place, well documented, and consistently followed for a school to be able to regulate what a student says or distributes and there must be no endorsement of any particular ideas from any group or student. Cell phones The next topic of discussion is cell phones in classrooms. The article being summarized is entitled The Only Thing We Have to Fear is†¦120 Characters. In this article, Kevin Thomas and Christy McGee (2012) make arguments for the use of cellphones in classrooms in spite of the fact that 69% have banned them. This paper responds to the many reasons for disallowing their use, and then it goes on to highlight some ideas about why cell phones should be used as educational tools. Both sides of the discussion certainly make valid points. If 69% schools have taken students cell phones away, there must be some reasons. Thomas Mcgee (2012) identified and responded to four commonly offered rationales, including misuse for cheating, replacing Standard English with textese, sexting, and cyberbulling. It seems rather obvious that these are negative side effects of the technology, however there are also positive results that can be attributed to the use of cell phones. Today, they are relatively affordable and powerful miniature computers. When used properly, the possibilities for better use of time are astonishing. According to Thomas and McGee (2012), teachers need to be modeling appropriate behavior with their portable electronic devices and taking advantage of the benefits because the technology is not the cause of the problems. The problems being associated with cell phones all existed in some form, long before modern technology. Thomas Diamates (2010) reports that courts have supported schools in their efforts to ban cell phone use as long as the school follow established procedures. Bullying The third topic has to do with bullying, specifically students with disabilities. These students stand out in the classroom, as they are â€Å"different† and so they are subjects of increased abuse from fellow students (Eckes and Gibbs, 2012). Schools and teachers have an obligation to provide students with disabilities a free appropriate public education (FAPE) in the least restrictive environment according to the Individuals with Disabilities Education Act (2004). This paper looks at the findings in several court cases to establish what is required of teachers in situations where students with disabilities are being bullied. What this article shows is that there are an increasing number of suits against school where disabled children are being bullied. The interpretation of what is considered an appropriate education, and whether or not the school took proper preventative/disciplinary steps in light of the bullying are the reasons for these suits. The findings of this study provide evidence that the courts will generally side with schools that have taken and documented actions to alleviate the harassment. In Brown vs. Monroe County Board of Education (1999), the Supreme Court ruled that for a school to be liable, it must receive federal funds, it must have been aware of and acted â€Å"deliberately indifferent† to the harassment, and the bullying must have been severe enough to deprive educational opportunity (Eckes and Gibbs, 2012). Basically, schools must make an adequate effort to alleviate the harassment in order to limit their liability, and this has been upheld by the courts in cases like Werth v. Board of Directors (2007), and Biggs v. Board of Education (2002). Dress codes The last article on the list takes a look at how and why public schools can or cannot implement gender based dress codes. Proponents of dress codes list reasons including less distractions, less pressure to dress right, safety, and lower cost to families. Opponents say that dress codes take away students expressive rights, which are already severely limited in school settings. In this particular case, Ceara Sturgis had her picture and name removed from her senior yearbook because she is a lesbian who was more comfortable wearing the school prescribed male outfit. The current question is whether or not this is in violation of her civil liberties. Historically the courts have upheld the rights of schools to implement dress codes with very few exceptions. In Blau v. Fort Thomas Public School District (2005), a father brought suit against the school for violating 1st and 14th amendment rights with their dress code. The court found no violation of rights since â€Å"it is not related to suppression of the content of expression, it furthers a substantial government interest, and it does not burden substantially more speech than is necessary to further that interest† (Dowling-Sender, p. 34, 2005). On the other side of the coin, in United States vs. Virginia (1996), schools were required to show a â€Å"legitimate and important† reason for any gender based restrictions (Smith, 2012). In Ceara’s case, the school is going to have to show that it meets all these criteria, and the outcome has some potentially far reaching consequences. What all this means is that teaching in todays classrooms must be dynamic. Teachers need to be aware of their ever-changing legal and ethical obligations as educators. Decisions must be based on sound judgment and carefully documented observations. Teachers, students, and parents must work together and communicate with each other to create the best possible learning environment for everyone.

Gate Control Theory Of Pain Health And Social Care Essay

Gate Control Theory Of Pain Health And Social Care Essay OA knee pain prevalence, cost to NHS etc. Physio treatment of neck painà ¢Ã¢â‚¬  Ã¢â‚¬â„¢ electro modalities, esp TENS Pain is something that everyone suffers with at one time or another. Pain can be a huge burden on employers due to absenteeism (White et al, 2005). There are many methods used to relive pain with TENS being one method. Having completed a review of current literature, it is clear that the application of tens has a significant effect on the pressure pain threshold of a subject, however no study to date has researched the effects the positioning of the TENS being applied has on the pressure pain threshold. Therefore this study has the aim of investigating whether the positioning of the electrodes at the nerve root level will affect the pressure pain threshold of the relevant dermatomal area giving rationale for the use of TENS as a pain reliving modality for injuries to the extremities. Literature Review 4k Literature Search This research is investigating the effect of transcutaneous electrical nerve stimulation at a nerve root has on the pressure pain threshold at the periphery in relation to osteoarthritis of the knee. A review of the current literature was conducted using the following databases: PubMed, ScienceDirect, MetaLib (Cardiff Universitys Electronic Resources) and Google Scholar for journals dated 1982-2012. The main key words used in the search included, transcutaneous electrical nerve stimulation, pain, osteoarthritis, knee, and periphery. Backchaining was also used to ensure all relevant literature was obtained. Introduction Osteoarthritis a very common joint disorder occurring in any joint but most commonly in the hip, knee, the joints of the hand and foot, and spine (Symmons et al. 2003). It mostly affects those aged 60 and over with approximately 40% of people over the age of 65 suffering symptoms associated with knee OA (Zhang et al., 2008) resulting in globally nearly 250 million people having osteoarthritis of the knee, 3.6% of the population (Vos et al. 2012). This resulted in osteoarthritis becoming the fourth leading cause of disability in the year 2000 (Symmons et al. 2003) and costing the NHS a total of 25 million pounds in 2008 (NICE 2008) Arthritis knee Osteoarthritis of the knee is a chronic degenerative disorder with a multifactorial aetiology (Felson, 2000). This includes general factors; such as age, sex and obesity, mechanical factors; such as alignment and trauma (cooper et al. 2000) and genetic factors (Reginato et al. 2002). Osteoarthritis of the knee is characterised by both loss of articular cartilage and by central and marginal new bone formation (subchondral sclerosis, osteophytes) (Woolf and Pfleger, 2003). There is also often thickening of the capsule and low grade synovitis resulting in alterations in biomechanics of the joint. Osteoarthritis affects the whole joint with secondary changes including ligament laxity due to articular cartilage loss and muscle weakness around the joint due to disuse respectively (Felson 2000). Osteoarthritis of the knee is associated with pain, joint stiffness and deformity, which in turn lead to limitations of daily activities for sufferers. Although there is currently no cure available, there are a number of treatment options open to sufferers to provide symptomatic relief, as well as joint function improvements. There are many non- pharmacological treatment options available such as education, rehabilitation exercises, manual therapies, acupuncture and electro-modalities such as TENS. There is also a wide range of pharmacological measures available, non-steroidal anti-inflammatory drugs, oral analgesia and topical treatments. Pharmacological treatments also include intra-articular modalities such as injections of corticosteroid and hyaluronic acid and tidal irrigation to reduce symptoms. In severe cases, where nonsurgical interventions have failed, more invasive approaches may be needed (Cooper et al 2000) including therapeutic arthroscopy and joint replacement. Models of Pain Pain something that the medical profession aims to alleviate in all patients suffering from it. In order to do this an understanding of the function of pain is needed as well as knowledge of the physiological processes the cause pain. Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage (Bonica 1979). It serves as a stimulus to motivate an individual to cease or withdraw form damaging or potential damaging situations, or to protect a damaged body part during the healing process (Winlow et al. 1984). There are three main models of pain, the cognitive-behavioral model of pain, the gate control theory of pain and the neuromatrix theory of pain. Gate control theory of pain The gate control theory suggests there is a neurological gate in the dorsal horn of the spinal cord (Melzack and Wall 1967). This gate either blocks pain signals or allows them to continue to the brain. This gate in the spinal cord differentiates between the types of fibers carrying pain signals. Pain signals travelling down the larger C nerve fibers are blocked whereas pain signals travelling done the smaller a-delta nerve fibers are allowed to pass through and therefore continue up to the brain where the pain can be perceived (cord (Melzack and Wall 1967). This gating mechanism is influenced by descending nerve impulses from the brain in response to ascending pain stimuli. Cognitive behavioral theory of pain The cognitive behavioural pain theory explores the perception of pain by relating it to more than just the physical and physiological attributes of the pain mechanism, and explores the predisposing and perpetuating factors as well as the psycho-social aspects involved in pain perception (Letham et al. 1983). This model explains why some individuals continue to experience pain after trauma has healed, or display a pain response disproportionate to the original condition. The theory states that the perception of pain is influenced by predisposing factors such as personality, coping style and previous history of illness, as well as perpetuating factors such as behaviour, emotions, and physical symptoms (Letham et al. 1983). This explains why some individuals suffer with continued pain after the original injury has resolved and are driven by fear of further pain leading to increasingly restricted activities despite the original injury being resolved, exhibit a maladaptive avoidance response. While other will experience very little pain in situations that would otherwise be excruciating, for example soldiers in battle (Letham et al. 1983) Neuromatrix theory of pain The pain neuromatrix theory is a development of the gate control theory of pain. A widespread distribution of neurons imprint a neurosignature upon nerve impulse patterns that pass through the sensory matrix (Melzack 2001). This neurosignature creates the experience of self and gives subsets of patterns that give unique experiences such as pain. The perception of pain in the brain would be as the end result of an activation of the pain neuromatrix with a characteristic pattern relating to the pain signature (Melzack 2001). This is part of a multi system response to a perceived threat. However there are many other inputs that can trigger the pain neuromatrix in the brain including movement, touch, fear and visual stimuli (Melzack 2001). This is due to the fact that the widespread neurons which make up the neuromatrix for pain perception are involved in many other activities so the pattern for pain perception can be triggered by other groups of neuromatirx being active during other activities not purely the pain neuromatrix Pain and pathways There are four basic processes involved in nociception(processing of pain), Transduction, transmission, perception and modulation (McCaffery and Pasero, 1999). Transduction begins when nociceptors (free nerve endings) of either the A-delta fibres or C fibres of the primary afferent neurones respond to noxious stimuli. A noxious stimulai occurs when tissue is damaged and inflation occurs. The nociceptors are found in the somatic structures (skin, muscles, and joints) as well as the visceral structures (organs such as gastro-intestinal tract or the liver). (Wood 2008) Although both the C fibre and A-delta fibres are Primary afferent fibres they have different cell structures and are associated with different pain qualities (table 1). Table 1: Characteristics and functions of C fibres and A-delta fibres (Farquhar-Smith 2007) C fibres A-delta fibres Characteristics: Small diameter Unmyelinated Slow conducting Receptor type: Polymodal: respond to more than one type of noxious stimuli: Mechanical Thermal Chemical Pain quality: Diffuse Dull Burning Aching Referred to as slow or second pain Characteristics: Large diameter Myelinated Fast conducting Receptor type: High-threshold mechanoreceptors: respond to mechanical stimuli over a certain intensity. Pain quality: Well-localised Sharp Stinging Pricking Referred to as fast or first pain There are three stages to the transmission of pain; first the impulse is transmitted from the site of transduction along the nociceptor fibres (first order neurons) to the dorsal horn, in the spinal cord, where both C fibre and A delta fibres terminate. In the dorsal horn they synapse with the second order neurons and which then cross the spinal cord via the anterior white commissure and ascend to the thalamus via the two main nociceptive ascending pathways. These are the spinoparabrachial pathway and the spinothalamic pathway. The thalamus then directs the nervous impulse to multiple areas of the cortex and higher brain for processing as there is not a discrete pain centre (Wood 2008). The end result of the pain transmission is the perception of pain. This is where pain becomes a conscious and multidimensional experience with affective-motivational, sensory-discriminative, emotional and behavioural components. When painful stimuli are transmitted to the brain stem and thalamus, three main cortical areas are activated, the reticular system, the somatosensory cortex, and the limbic system, each one is responsible for a different response to the pain stimuli. (McCaffery and Pasero, 1999) The reticular system is responsible for the autonomic and motor response to pain, for example, automatically withdrawing from a painful stimulus. It also plays a role in the affective-motivational response to pain, such as assessing an injury after pain has occurred. The somatosensory cortex is involved with the interpretation and perception of sensations. It identifies the location, type and intensity of the pain sensation and relates this sensation to past experiences before triggering a response. The limbic system is responsible for the behavioural and emotional response to pain as well as past experiences of pain. The modulation of pain involves altering or inhibiting the transmission of pain impulses in the dorsal horn of the spinal cord. The complex pathways involved in the modulation of pain are called the descending modulatory pain pathways (Ossipov et al. 2010). These pathways can lead to either an excitatory response (an increase in the transmission of pain impulses) or an inhibitory response (a decrease in transmission of pain impulses). Descending inhibition produces an analgesic effect by causing the release of inhibitory neurotransmitters which partially or completely block the transmission of pain impulses in the spinal cord (Ossipov et al. 2010). Endogenous pain modulation helps to explain the wide variations in the perception of pain in different people as individuals produce different amounts of inhibitory neurotransmitters. Endogenous opioids are found throughout the central nervous system (CNS) and prevent the release of some excitatory neurotransmitters, for example, substance P, therefore, inhibiting the transmission of pain impulses. Physiotherapy and treatment of Pain Transcutaneous electrical nerve stimulation (TENS) papers on TENS and Pain (critical review of the literature) Transcutaneous electrical nerve stimulation (TENS) is an electro therapy procedure the aim of which is pain relief. During treatment a low amplitude and frequency alternating electric current is passed between two electrodes placed on the body resulting in stimulation of the nervous system. Research will be reviewed examining the theory that TENS is an effective pain reliving modality. Previous studies by Chesterton et al (2002, 2003) Vance et al (2012) and Chen et al (2010) have all shown TENS to be an effective form of pain relief against blunt pressure pain with. All however have used different parameters for both the TENS settings and application sites. All of the previous studies looked at found TENS to be an effective method of pain relief based on pressure pain threshold measurement. Both of Chestertons and Vances studies found a statistically significant increase in pressure pain threshold after a twenty minute application of TENS (p=0.005, p=0.01, and p=0.002 respectively). Chen also found a significant difference in post TENS of p= Vance was the only study to look at other forms of pain measurement s outcome measures, as well as the use of a pressure pin threshold measure similar to the other studies a cutaneous mechanical pain threshold measure using Von Frey filaments and heat pain threshold measure were also used. Although using these additional outcome measures to assess the effectiveness of TEN as a pain reliving modality it was only the pressure pain threshold measure that yielded a significantly change. Therefore the results of the study can still only be extrapolated to the pressure pain reliving abilities of TENS and no other forms of pain. Both Vance and Chen explored the differences between the frequencies TENS applied. Chen uses 3Hz for low frequency and 80Hz for high frequency. Vance does not specify the actual frequency used and only states high and low frequency Tens was used with the definition of High frequency TENS >50Hz and Low frequency TENS In Chestertons 2002 also explored the differences between the frequencies of TENS applied using 4Hz as the low frequency and 110Hz as the high frequency. The results were similar to Chen with the high frequency TENS proving a more affective pain reliving modality of TENS. All three studies have good internal reliability, the same experimenter was used for every measurement, and standardised testing procedures were used. The rate of application of the algometer was kept constant when measuring the pressure pain threshold and the same point was used on each subject for the measurement. Chen and Vance, however, relied sole on the skill and consistence of the experimenter to ensure the pressure pin threshold reading was taken in the same manner for every subject. Chestertons studies used a special mounting frame for the algometer to ensure that it was perpendicular to the skin and that the rate of application was constant. This improved the internal reliability of the study as each subject will have had the reading taken in exactly the same way. Chesterton and Chen both use healthy volunteers as the subjects in their studies. Both studies have a good sample size with an equal distribution of males and females. Chen subjects have a small age range (mean  ± SD, age 26.7  ± 2.9 years) which is not representative of the population. Chestertons sample has a much larger are range (mean  ± SD, age 30 ± 7 years, range 18-57 years) which is a far closer representation of the general population and makes the extrapolation and application of the results more reliable. However both of these studies, due to only using healthy subjects, cannot be reliable extrapolated to apply to people who are not healthy. Therefore it cannot reliably be said that anyone suffering with a painful condition, be it degenerative, trauma, or surgical, will benefit from the application of high frequency TENS or that it will reduce their pain. It can only reliable be said that it will reduce the pain perceived in healthy individuals. This however is add ressed by Vance, although using smaller sample size than Chesterton all of the subjects used in the study all had a diagnosis of medial compartment osteoarthritis of the knee. Unlike the other studies Vance did not have an equal split of male to female subjects (29 male 46 female), however by using a stratified randomisation process it was ensure that each experimental group had the same ratio of male to female subjects. Therefore unlike the other studies Vances results can be reliably extrapolated to apply to a population with a diagnosis of medial compartment osteoarthritis of the knee, and high frequency TENS can be reliably used as a pain reliving modality. Random allocation of groups Not all subjects tens naive Blinding All have good baseline comparability between groups. Chen Good base line A paired t-test on this data found no significant differences (mean + SD = -1.50  ± 5.65N,  P  = .143) Chesterton 2002 Good basleine similar This was confirmed by a one-way analysis of variance (ANOVA) for pre-treatment mean MPT (P 0:19 Chesterton 2003 Good One-way analysis of variance (ANOVA) showed no significant differences in PPT, between the groups at baseline (p 0:142) Vance Bad not equal gender split 29 male 46 femle. But good that same ration in each group. Good There were no significant differences between groups in demographic characteristics, with the exception of body mass indexes (P.027). Algomiter reliability Aim(s) Hypothesis (hypotheses) Does High-TENS affect pressure pain threshold (PPT) at the periphery? Null Hypothesis: There will be no difference in the pressure pain threshold between the control group and experimental group. Methods Design This study was an experimental repeated measures clinical trial. The independent variable being assessed was transcutaneous electrical nerve stimulation. The dependent variable was Pressure pain threshold. The study included 20 people who had no previous history of knee pain and had not previously experienced TENS. Subjects attended two sessions with a 48 hour interval. In the first session subjects were given a placebo TENS and in the second a single high frequency TENS treatment. Outcome measurements were obtained before and during each treatment. Ethical approval for the study was granted by the University Ethics Committee (Cardiff University, 2012). Participants A convenience sample of 20 subjects from Cardiff University School of Healthcare was used. The inclusion criteria consisted of being a healthy subject. Subjects were screened for relevant contraindications and exclusion criteria including: pacemakers, heart disease or arrhythmias, undiagnosed pain, epilepsy, peripheral neuropathy (Fox and Sharp, 2007), history of trauma or surgery to the dominant leg in the last 6 months, medication, history of pregnancy or knowledge or use of TENS treatment (Chesterton et al., 2002). No subjects were excluded. The experimental procedure was explained to each subject who then signed a consent form witnessed by an independent person (Appendix 4). At the first session, subjects were assessed for bilateral recognition of sharp versus dull pressure at the L3 dermatome to rule out loss of sensation. Ethics Ethical approval was obtained from The School of Healthcare Studies Ethics committee Cardiff University and a single blind experiment using repeated measures was used. A risk assessment was carried out for the pilot and data collection assess risk to the subjects and the investigator using the standard risk assessment method of the cardiff university Physiotherapy department. The risk is quantified by the Risk Rating Number which is calculated by multiplying the probable frequency by the potential severity. For this research the probable frequency is unlikley scoring two and the potential severity is negligible scoring one (appendix 1). The Risk Rating number is two which requires no further action (Cardiff Univeirsity 2012). Individuals with a history of knee pain were excluded, reducing the likelihood of physical injury to the subjects during the PPT measurement process. In the event of an injury subjects would be withdrawn from the study and appropriate medical advice would be sought. The privacy and dignity of the subjects during electrode placement was ensured by using screens, and gaining informed consent before exposing the skin on the back. The information sheet given to the subjects (Appendix 3) informed them of what the study involved, and that the results would be analysed as part of this research project. Subjects were informed they were free to withdraw from the study at any time. All data was confidential and anonymous. All data stored on a computer was and password protected and anonymous. Pilot study A pilot study was conducted on 3 subjects not included in the main study prior to data collection. This was to ensure that the method to be used was satisfactory and to allow researcher to familiarize themselves with the equipment. It also allowed the researcher to estimate the time required, allowing appropriate time slots to be set. Another reason for the pilot study to be carried out was to expose any unforeseen errors or limitations in the design protocol allowing modification as necessary (Jenkins et al, 1998). The pilot study highlighted variations in subject foot placement in sitting, in turn effecting the knee positioning needed for a PPT reading to be taken. It was therefore decided to give subjects the following verbal command on how to sit, sit with your feet flat on the floor and your knees at ninety degrees, to minimize variance in knee position. The rest of the method was deemed sufficient and no further changes were made. Apparatus The pressure pain threshold was assessed using a handheld pressure algometer (Algometer commander, Jtech medical, United States) with a flat circular metal tip measuring 1.1 cm in diameter. The force was displayed digital in increments of 0.1N and applied at a rate of at 5N/s (Chesterton et al 2002). The subjects were instructed to say stop when the sensation first became painful. A practice test was first performed on the non-dominant knee to familiarize subjects with the procedure. The use of a pressure algometer for measuring pressure pain threshold has excellent test-retest reliability (r.70-94) (Fischer, 1987), and is a valid measure for deep-tissue hyperalgesia as discussed by Staud et al. (2007) Electrical stimulation was generated via a commercially available a dual channel, TENS unit (200 plus, TPN), the unit uses an asymmetrical, biphasic waveform. The pulse width was set at 50 microseconds and the frequency 150Hz, and the intensity was increased to the subjects verbal report of when the feeling became strong but still comfortable. Procedure. Before taking part in the study, all subjects were given an information sheet (appendix 3) explaining research study and what would be expected from them if they participate and completed a consent form (Appendix 4). Subjects came in on two separate occasions 48 hours apart; once for the control trial (sham TENS) and once for the application of TENS. In the first session demographic data was obtained, which included age and gender. A standard sharp/blunt discrimination test was performed, using neurotip at each stimulation site, to ensure intact skin sensation. The skin was then cleaned using an alcohol wipe before the application of electrodes (Chesterton et al., 2003). Two TENS electrodes were then placed over the L3 spinal level. Each electrode was placed over the L3 Spinal nerve root the location of which was found by palpating to the L3 spinal level (Rhoades et al. 2009). The first electrode was positioned 10mm to the left of the L3 spinal process with the second positioned 10mm to the right. The center of each the electrode was placed level with the inferior aspect of the L3 spinal process (figure 1). Experimenter 1 was responible soley for the electrode psoiting nd TENS application to ensure internal reliability. Figure 1 Subjects were seated in a comfortable upright position with feet flat on the floor. The position of the pressure pain reading was then marked bilaterally. This was done by measuring 30mm superior to the central aspect of the superior border of the patella in flexion (figure 2). Experimenter 2 was responsible solely for the positioning of the pressure pain reading and the algometer application to ensure internal reliability. Figure 2 A practice pressure pain measurement was then performed on the subjects non dominant side with subjects instructed to say stop when the sensation first became painful. At this point the experimenter immediately retracted the algometer. (Chesterton et al. 2003) This process was then repeat three times at 30 second intervals on the dominant side to establish a base line figure (Vance et al 2012). The Tens machine was then turned on and the intensity increased to the subjects verbal report of when the feeling became strong but still comfortable. For the sham TENS subjects were told that some forms of TENS were imperceptible and, they might not feel any sensation. The battery in the TENS unit was inserted the wrong way round. The unit was still visibly switched on and the intensity turned up, but no current was flowing (Chesterton et al 2003). A 30 minute timer was started as soon as the intensity was correctly adjusted. When the 30 minute time period had elapsed three further pressure pain threshold readings were taken again at 30 second intervals on the dominant side to a post treatment figure. Once these reading were taken the TENS machine was turned off and the electrodes removed. Subjects were monitored for a further 30 min after the end of the stimulation period (Chesterton et al 2002). Subjects returned for the second session 48 hours later. Data Analysis All data was entered into Windows Excel version 2010 Descriptive analysis was carried out using means, standard deviations this was presented as tables and graphs. The data was then entered into SPSS (Statistical Package for Social Sciences version 20.0). The data was interval ratio and the study investigated one group of subjects. A paired t-test was conducted to compare the percentage change in pressure pain threshold between the control and high TENS conditions. A statistical significance level of 95% (p Results The demographic data can be seen in Table 1. The following tables and graphs present both descriptive and statistical analysis of the pressure pain threshold data. All SPSS outputs can be seen in appendix 5 and raw algometer data can be seen in Appendix 6. Table 1: Demographic Characteristics of Sample N minimum maximum mean S.D Age 20 19 23 19.95 1.09904 Key: N = Number of subjects S.D = Standard Deviation A small standard deviation is seen for the age of subjects in Table 1. The male to female ratio was 1:1 with 10 female subjects and 10 male subjects. All subjects met the inclusion and exclusion criteria, and all were able to complete the study. Discussion There are two primary and related theories for explaining the efficacy of TENS in chronic or acute pain relief. The gate theory (Wall, 1965 (Melzack R, Wall P. Pain mechanisms: a new theory. Science. 150(699):971-979,1965)) proposes that pain transmission relies on a gate to the thalamus and cortex for nocireceptive information to be interpreted as pain. This theory postulates that inhibition of nocireceptors can be caused by rapid impulse activation of myelinated nerve fibers. The second related theory postulates that neurotransmitter exhaustion can be caused by rapid nerve activation outside of its refractory period, and that the temporary exhaustion of neurotransmitters would provide pain relief until such time as neurotransmitter synthesis had refilled the synaptic junctions (Kaye, 2007(Transcutaneous Electrical Nerve Stimulation: WebMD eMedicine. http://www.emedicine.com/pmr/topic206.htm January 26, 2007)). Limitations Clinical Implications Further research Conclusion

bird feeders :: essays research papers

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High School and Prompt Essay

1. Situation: Many high school students hold part-time jobs after school. Directions: Think about the effects part-time jobs have on students. Do part-time jobs hinder or help a student’s educational goals? Prompt: Now write to convince your guidance counselor to accept your view of high school students holding part-time jobs. 2. Situation: Universities and colleges require that entering freshmen must have taken at least two years of a foreign language on the high school level before graduation. Directions: Think about the advantages and disadvantages of taking two years of a foreign language in high school. Prompt: Write an essay to convince a university or college whether or not two years of a foreign language be a requirement for high school. 3. Situation: Technology has become vital in our modern society. It acts as both a source for knowledge and for enjoyment. Directions: Think about technology’s role and connection with education. Does it help or hinder? Prompt: Write to convince the school board to accept your view of technology and its role in your school. 4. Situation: Your school board members have been asked to consider banning music playing devices (i. e.MP3 layers, CD players) from schools due to distractions they cause in classrooms. Directions: Think about the effects of listening to music playing devices in the classroom have on you and your friends. Prompt: Now write to convince your school board members to accept your point of view on whether music playing devices should be banned from schools. 5. Situation: Your school has decided to grant your grade level one privilege that the other grades in your school do not have. Directions: Think of one privilege that your class does not have that you would now like to have. Prompt: Now write to convince the administrators of your school to grant this privilege to your class for the rest of the year. 4 10th Grade Persuasive Essay Prompts 6. Situation: Many students feel that taking physical education in high school is not necessary, while others see great benefit in it. Directions: Do you feel that physical education should be a graduation requirement? Prompt: Now write to convince your legislators to accept your point of view. 7. Situation: Students are legally allowed to drop out of school after they reach the age of 16. The state is currently considering a bill which will raise this age to 18. Directions: Think about the problems or benefits of raising this age to 18. Prompt: Now write to convince your legislators to accept your viewpoint on the mandatory age for dropping out of school. 8. Situation: Your principal is thinking of rewarding students who pass the 10th grade FCAT on the first try. Directions: Think of rewards that you believe would be in the realm of possibility and would be effective motivators so that more students would do their best on this test. Prompt: Now, write to convince your Principal to accept your reward package. 9. Situation: State guidelines have re-outlined the high school math sequence. All students will soon be required to take geometry before graduation. Directions: Think about the challenges of all students taking geometry. Prompt: Now, write to convince your legislators to accept you point of view on whether geometry should be required before graduation. 10. Situation: Celebrities normally get paid many times the amount that fire-fighters, teachers and policemen earn. Directions: Think about whether you believe that celebrity salaries should be lowered. Prompt: Now write an essay to convince the public that your point of view is justified. 5 10th Grade Persuasive Essay Prompts 11. Situation: Online dating services have become popular in recent years. Directions: You have corresponded online with someone that you would now like to meet face-toface. You realize that there may be safety issues involved. Prompt: Now, write to convince your parents to allow this visit. 12. Situation: Many people believe that it is dangerous to talk on a phone while driving a car. The state legislators are considering making it against the law for people to use a cell phone while operating a motor vehicle. Directions: Think about how you feel about people talking on a cell phone while driving a car. Prompt: Now write to convince your state legislators to accept your view about whether or not to make it against the law to talk on a phone while driving. 13. Situation: At the present time, young Americans volunteer to enlist for military service. To maintain our present military operations, more people may be needed. Directions: Do you agree or disagree with the opinion that all Americans, both men and women, should be required to perform two years of military service? Prompt: Write an essay in which you persuade the reader to support your point of view. Support your position with specific reasons and examples. 14. Situation: A law has been passed that requires high school students to pass exit tests before they graduate from high school. Directions: Consider carefully the advantages and disadvantages of passing required exit tests. Do you agree or disagree with making high-stakes exit tests, such as the FCAT Test, a requirement for high school graduation? Prompt: Write an essay in which you persuade the reader to support your point of view. Support a position with specific reasons and examples. 15. Situation: Many celebrities-such as actors, musicians, models, or athletes-make a great deal of money. Some people think celebrities make more money than they deserve. Other people think celebrities’ wealth is deserved because of the enjoyment they bring to the public. Directions: Do you agree or disagree that celebrities make more money than they deserve? 6 Prompt: Now, write an essay in which you persuade the reader that your side of the issue is correct. Use facts and examples to support your argument. 16. Situation: Current research suggests that because teenagers have different sleep patterns, they would benefit from beginning the school day at a later time. Suppose your Board of Education has proposed that all high school schedules begin at 9:30 a. m. and end at 4:30 p. m. Directions: Do you agree or disagree that this later schedule would be beneficial? Prompt: Now write an essay in which you persuade the Board of Education to agree with your opinion. Support your position with reasons and examples. 17. Situation: Due to potential problems, many school systems have adopted a policy that bans cell phones and pagers on school grounds. However, some parents have provided these items out of concern for safety. Directions: Do you agree or disagree that cell phones and pagers should be banned on school grounds? Prompt: Now write an essay in which you convince the reader of your opinion. Support your position with specific reasons and examples. 18. Situation: A law has been passed changing the driver’s license system to a graduated system. A young person can be issued a restricted learner’s permit at age 15, an intermediate license at age 16 and a full license at age 17. Both the learner’s permit and intermediate license limit the number of passengers allowed in a car and limit the hours the person can drive. The full license carries no restrictions. Directions: Consider carefully the advantages and disadvantages of the graduated driver’s license system. Do you agree or disagree with the graduated license system? Prompt: Now, write an essay in which you persuade the reader to support your point of view. Support your position with specific reasons and examples. 19. Situation: A school board is considering keeping school in session all year. Instead of a long summer vacation, there will be many shorter breaks throughout the year. Directions: Think about the effects of a twelve-month school year. Do you agree or disagree that schools should be in session all year? Prompt: Now, write an essay in which you persuade the reader why this is or is not a good idea. Defend your position with specific reasons supported by several detailed examples. 20. Situation: In some countries, students are responsible for the basic daily cleaning of their school buildings. Fifteen minutes are set aside each day for all students to sweep, dust, and clean their classrooms and corridors. 7 Directions: Think about how you would feel if students were responsible for cleaning your school. Do you agree or disagree that American schools should adopt this policy? Prompt: Now, write an essay in which you persuade the reader why this is or is not a good idea. Defend your position with specific reasons supported by several detailed examples. 21. Situation: Imagine that your school district has proposed saving money by eliminating extracurricular sports (football, basketball and baseball) from the high school program. Directions: Think about the possible effects of cutting sports from the school program. Decide whether you are for or against this proposal. Prompt: Now write an essay in which you persuade the reader why this is or is not a good idea. Defend your position with specific reasons supported by several detailed examples. 22. Situation: Many schools require all students to perform some type of community service such as working in nursing homes or hospitals. Directions: Think about how you would feel if you were required to perform a community service. Prompt: Now write an essay in which you persuade the reader that students should or should not be required to perform community service. Defend your position with several detailed reasons. Develop those reasons with supporting examples. 23. Situation: Since schools have seen a rise in gang violence, stealing, and discipline problems, many schools and school districts are considering requiring students to wear uniforms. Directions: Think about how you would feel if you were required to wear a school uniform. Are there benefits or drawbacks to requiring students to wear school uniforms? Prompt: Now write an essay in which you persuade the reader that school uniforms should or should not be required. Defend your position with specific reasons supported by several detailed examples. 24. Situation: A graduate from your high school has made a large financial gift to your school and has requested that the money be used to improve the educational experience for students. This donor has also asked that students be able to recommend how the money should be used. Directions: Think about how this financial gift should be used at your school. it could be used to expand the use of technology, add new courses, or improve the library or media center. Choose one of these options or one of your own. Prompt: Write a persuasive essay stating your recommendation. Provide supportive reasons to convince school officials why the money should be spent on your recommendation. 8 10th Grade Expository Essay Prompts 1. Situation: A friend of yours is considering moving to your town soon. Directions: Think about the reasons why you like living in your town. Prompt: Write to explain why you like living in your town. 2. Situation: Everyone has a possession that he/she cherishes. Directions: Think about an object that is your prized possession and why it has special meaning to you. Prompt: Write to explain why the object is your prized possession. 3. Situation: In recent years, many areas in the United States have experienced natural disasters, such as floods, earthquakes, hurricanes, and tornadoes. Directions: Think about ways young people should respond to help people in other communities that have experienced natural disasters. Prompt: Write to explain ways young people may respond to help people in other communities affected by natural disasters. 4. Situation: Each year, many teenagers are killed or injured by driving under the influence of alcohol or by riding in a car driven by an alcohol-impaired teen. Directions: Think about how these alcohol-related deaths or injuries can be reduced. Prompt: Write to explain solutions to help stop other teens from risking their lives by driving under the influence of alcohol. 5. Situation: School violence has increased significantly over the past several years. Directions: Think about reasons why school violence is on the rise. Prompt: Write to explain why school violence has increased over the past few years. 6. Situation: Teenagers are often influenced by celebrities. Directions: Think about a celebrity who positively affects teens. Prompt: Write to explain how a celebrity can serve as a positive role model to teens. 9 10th Grade Expository Essay Prompts 7. Situation: Obesity is becoming a national health issue. Directions: Think of reasons why Americans are gaining weight and becoming obese. Prompt: Write to explain reasons why Americans are fighting the weight battle. 8. Situation: The cost of gasoline has risen drastically. Directions: Think of alternatives to paying such outrageous prices for fuel. Prompt: Write to explain what alternatives you would use to save money. 9. Situation: As the price of gasoline continues to rise, American consumers are paying high prices for a gallon of gas. At the same time, oil companies are making record profits. Directions: Think about legal ways you as a consumer can send a message to the oil companies that American consumers are being hurt financially by paying too much for a gallon of gas. Prompt: Write to explain legal ways consumers can take action to fight the rising cost of gas. 10. Situation: Everyone has had a memorable teacher. Directions: Think about the positive influences a teacher has had on you and your educational goals. Prompt: 11. Situation: Write to explain your most memorable teacher. Many people in this country care more about the way they look and having a lot of nice things, like cares and clothes, than about the problems of society. They do not pay enough attention to problems such as crime, poverty, or unemployment. Directions: Do you agree or disagree with this statement? Prompt: Write an essay in which you explain your opinion. 12. Situation: Your school has a program in which a tenth grader acts as a mentor for a ninth grader at the beginning of each school year. The mentor’s job is to  help the ninth grader have a successful experience at your school. The ninth grader you are working with is worried about being able to write well enough for high school classes. 10 Directions: As you plan your response, think about your own writing experiences. How would you describe â€Å"good† writing? What advice about writing has been helpful to you? What writing techniques do you use? Prompt: Write a letter to your ninth grader explaining what kind of writing is expected in high school classes and what the student can do to be a successful writer in high school.

The African Diaspora

The African Diaspora Introduction African Americans that had been transported to America as slaves found themselves lost with no sense of identity. It was a White man’s world and the Black man felt ostracized. In seeking to have a connection with their original culture, the Blacks began to connect with African culture in terms of dressing, religion and way of life. However, it was a challenge. They were not only African but they were also American. What did African American mean?Advertising We will write a custom essay sample on The African Diaspora specifically for you for only $16.05 $11/page Learn More In this paper, I show that the appreciation of the African Diaspora continues as the African Americans seek to treasure the struggles their ancestors went through. They also want to connect with their African heritage and culture in order to have a positive identity about themselves The Appreciation of the African Diaspora Continues It has been a long journey of African Americans towards freedom. There are writers who wrote on the racism and segregation that was prevailing in the 1920’s to 1940’s. James Baldwin in the short story, Previous Condition, narrates how Peter is thrown out of a white neighborhood in New York by the landlady. You get outa my house! She screamed. I got the right to know whos in my house! This is a white neighborhood; I dont rent to colored people. Why dont you go on uptown, like you belong? (Baldwin, 1976, pg77).His friend, Jules, was renting it and had allowed Peter to live in the room. The story is set in 1948. He had tried to hide from being seen but he had been unsuccessful. Nella Larson, in her story, Passing narrates the challenges that Blacks faced at that time. Claire, an African American, who is light skinned, passes herself off as a White woman in order to get opportunities that were not available for Blacks at that time. She marries a white man who does not know she is Black. Her husband is a racist . When asked by Claire to explain to her friends why he calls her Nig he says â€Å"Well, you see, it’s like this. When we were first married, she was as white as ⎠¯ as ⎠¯ well as white as a lily. But I declare she’s gettin’ darker and darker. I tell her if she don’t look out, she’ll wake up one of these days and find she’s turned into a nigger.† He roared with laughter† (Larson, 2003, pg 24) It is against these conditions that the African Americans sought to appreciate their culture. After the abolishment of slavery, several Blacks rose against the concepts of assimilation and integration. They wanted a complete restructuring of the country’s political and economic system. Despite the Civil Rights Act, Blacks were still facing racism. They also wanted to have an African-based culture to give them identity and a positive self-image.Advertising Looking for essay on african american? Let's see if we can help you! Get your first paper with 15% OFF Learn More The experience of racism and Jim Crow Laws had caused them to feel inferior to the Whites. They had been estranged from the past. The people therefore advocated for cultural pluralism. The Blacks started looking at Africa and appreciating it as a place of rich culture. They appreciated the black’s effort in Africa through fighting to fend off imperialism and White dominancy. The whites only wanted to gain wealth through their labor. Du Bois notes that the civil war between the South and North was mainly about the slaves and not any other reason. He writes that â€Å"It was thus the black worker, as founding stone of a new economic system in the nineteenth century and for the modern world, who brought civil war in America. He was its underlying cause, in spite of every effort to base the strife upon union and national power. That dark and vast sea of human labor in China and India, the South Seas and all Afric a; in the West Indies and Central America and in the United States- that great majority of mankind, on whose bent and broken backs rest today the founding stones of modern industry- shares a common destiny† (Bois, 1998, pg15) After the civil war, the South started to reconstruct their social and political systems to accommodate free slaves who could vote. However the gains were lost when certain Whites took over who felt that the Whites should be segregated from the Blacks. It led to the Jim Crow laws of segregation. The African Americans migrated from the hostile South to the north to search for a better standard of living. The Blacks refused to quietly allow the Jim Crow laws to depress them. There arose a surge in the African American culture expressed in literature, music and art. Through these forms of art they sought to challenge the prevalent racism at that time. It came to be known as the Harlem Renaissance. They were defiant and wanted to live better lives. There aros e art institutions for African culture. In 1965, Dr Robert Pritchard established a guild society known as the American Festival of Negro Art. Later, the Morris College held a Negro History week where they showed African art and appreciated contributions by black artists to American jazz and literature. Leaders of this ethnic movement sought for schools to teach African American history. In the ghettos, there was frustration with the country’s economic and political development yet there was no progress or improvement in their lives. The blacks started to vote for black leaders who would bring change.Advertising We will write a custom essay sample on The African Diaspora specifically for you for only $16.05 $11/page Learn More Conclusion Currently, due to the Blacks seeking to know their history there is so much information on the African American history and experiences. The African Diaspora will still continue even as the African Americans seek to i dentify their culture and appreciate it. It is treasured due to the struggles their ancestors went through to ensure that their culture is recognized and appreciated. Baldwin, James. â€Å"Going to Meet the Man† USA: Dell Publishers. 1976. Print. Bois, Du. â€Å"Black Reconstruction in America 1860–1880†. New York: Free Press. 1998. Print. Larsen, Nelly. â€Å"Passing†. USA: Penguin Classics. 2003. Print.

Perl Array chop() and chomp() Function - Quick Tutorial

Perl Array chop() and chomp() Function - Quick Tutorial chop(ARRAY); chomp(ARRAY); Perls chop and chomp functions can often be a source of confusion. Not only do they sound similar, they do similar things. Unfortunately, there is a critical difference- ​chop removes the last character of the string completely, while chomp only removes the last character if it is a newline. $myName Jacob\n; chomp($myName); Chomping $myName cuts off the last newline, leaving just Jacob. Once its been chomped, further chomping wont do anything at all. Chopping the name, however, will result in the last character being removed, leaving Jaco: $myName Jacob; chop($myName); Chomping and chopping an array results each element being acted on, and can be a real time saver. chop(ARRAY); chomp(ARRAY); So remember - Chop chops off the last character without question or regret. Chomp only removed the newline, leaving the string itself intact. Chomp does not remove all whitespace characters by default. In fact, by default, chomp only removes what is currently defined as the $INPUT_RECORD_SEPARATOR. If your goal is to trim all whitespace from the end of your string, try using a regex like this one submitted by a reader: $line ~ s/\s*$//g;

How Electric Motors and Generators Work

How Electric Motors and Generators Work Electric vehicles rely exclusively on electric motors for propulsion, and hybrids use electric motors to assist their internal combustion engines for locomotion. But thats not all. These very motors can be, and are, used to generate electricity (through the process of regenerative braking) for charging these vehicles onboard batteries. The most common question is: How can that be ... how does that work? Most folks understand that a motor is powered by electricity to do work- they see it every day in their household appliances (​washing machines, vacuum cleaners, food processors). But the idea that a motor can run backward, actually generating electricity rather than consuming it seems almost like magic. But once the relationship between magnets and electricity (electromagnetism) and the concept of conservation of energy is understood, the mystery disappears. Electromagnetism Motor power and electricity generation begin with the property of electromagnetism- the physical relationship between a magnet and electricity. An electromagnet is a device that acts like a magnet, but its magnetic force is manifested and controlled by electricity. When wire made of conducting material (copper, for example) moves through a magnetic field, current is created in the wire (a rudimentary generator). Conversely, when electricity is passed through a wire that is wound around an iron core, and this core is in the presence of a magnetic field, it will move and twist (a very basic motor). Motor/Generators Motor/generators are really one device that can run in two opposite modes. Contrary to what folks sometimes think, that does not mean that the two modes of the motor/generator run backward from each other (that as a motor the device turns in one direction and as a generator, it turns the opposite direction). The shaft always spins the same way. The change of direction is in the flow of electricity. As a motor, it consumes electricity (flows in) to make mechanical power, and as a generator, it consumes mechanical power to produce electricity (flows out). Electromechanical Rotation Electric motor/generators are generally one of two types, either AC (Alternating Current) or DC (Direct Current) and those designations are indicative of the type of electricity that they consume and generate. Without getting into too much detail and clouding the issue, this is the difference: AC current changes direction (alternates) as it flows through a circuit. DC currents flow  uni-directionally (stays the same) as it goes through a circuit. The type of current utilized is concerned mostly with the cost of the unit and its efficiency (An AC motor/generator is generally more expensive, but is also much more efficient). Suffice it to say that most hybrids and many larger all-electric vehicles use AC motor/generators- so that is the type well focus on in this explanation. An AC Motor/Generator Consists of 4 Main Parts: A shaft-mounted wire wound armature (rotor)A field of magnets that induce electrical energy stacked side-by-side in a housing (stator)Slip rings that carry the AC current to/from the armatureBrushes that contact the slip rings and transfer current to/from the electrical circuit The AC Generator in Action The armature is driven by a mechanical source of power (for example, in commercial electric power production it would be a steam turbine). As this wound rotor spins, its wire coil passes over the permanent magnets in the stator and an electric current is created in the wires of the armature. But because each individual loop in the coil passes first the north pole then the south pole of each magnet sequentially as it rotates on its axis, the induced current continually, and rapidly, changes direction. Each change of direction is called a cycle, and it is measured in cycles-per-second or hertz (Hz). In the United States, the cycle rate is 60 Hz (60 times per second), while in most other developed parts of the world it is 50 Hz. Individual slip rings are fitted to each of the two ends of the rotors wire loop to provide a path for the current to leave the armature. Brushes (which are actually carbon contacts) ride against the slip rings and complete the path for the current into the circuit to which the generator is attached. The AC Motor in Action Motor action (supplying mechanical power) is, in essence, the reverse of generator action. Instead of spinning the armature to make electricity, current is fed by a circuit, through the brushes and slip rings and into the armature. This current flowing through the coil wound rotor (armature) turns it into an electromagnet. The permanent magnets in the stator repel this electromagnetic force causing the armature to spin. As long as electricity flows through the circuit, the motor will run.

Family Law Coursework Essay Example | Topics and Well Written Essays - 2500 words

Family Law Coursework - Essay Example Analysis First of all, the issue that is at hand is that James and Cara have not been living together for the past eight years. However, Cara has been performing all of the housework and maintaining of children since the two have been split up. Therefore, one can argue that Cara’s caring for the children might be considered to be domestic work that would influence her share of how much she would receive, equity-wise, in the house. However, different courts have treated the value of housework and child care differently in this regard. For instance, take the case of Burns v. Burns.2 In this case, the plaintiff did not contribute monetarily to the property and the maintenance of the property. However, she contributed value to the household by her role as a homemaker. The Burns court found, however, that this was not enough, and that the plaintiff did not have the right to a beneficial entitlement to the home because she did not contribute monetarily towards this. This case was ba cked up by the case of Oxley v. Hiscock.3 In Oxley, there were two unmarried people who owned a home and were cohabiting, just as in the case of Burns, and in the case at bar. While both parties had contributed towards the purchase of the home in Oxley, but the court did not consider the value of the plaintiff being a homemaker in that case, either, so the plaintiff did not get an increased value in her beneficial stake in the home because she was a homemaker. Abbott v. Abbott4 came to the same conclusion, stating that only monetary contributions could suffice for determining an equitable stake in property, although some conduct may be considered, if the conduct is directly related to the house itself. For instance, conduct which improved the value of the house, such as manually making repairs, would be considered, but conduct which is indirect, such as homemaking or housekeeping, would not be considered. However, another case, Drake v. Whipp5 came to a different conclusion. In this case, the female partner made under 20% of the financial contributions towards the shared home, but was awarded 33% of the property, in part because of her contributions as a homemaker. Other cases that were before the Burns case are also relevant. For instance, in Pettit v. Pettit,6 which involved a married couple, the husband did not contribute financially towards the couple's home, which was in the separate name of the wife before marriage. He labored on the home, but the court still found that he was not entitled to a beneficial interest in the home. In Gissing v. Gissing,7 the couple was unmarried, and the husband did not contribute financially to the home. He did, however, buy furniture and do chores, such as mow the lawn. Again, the court did not find a beneficial interest for the husband in this case. Lloyds Bank v. Rosset8 is yet another case that found that conduct alone would not give rise to a beneficial interest – in that case, the wife undertook actions that im proved the home, yet she did not contribute financially to the home. The wife was denied a beneficial interest, and the Lloyds court found that anything less than direct contributions to the purchase price of a home, or towards the mortgage, would suffice to show the intention of the parties that

Commercial assignment Example | Topics and Well Written Essays - 500 words

Commercial - Assignment Example Mistakes are most essential things that people should make to help them learn. This is because as it is often stated people learn through mistakes and for that reason, children should be allowed to make mistakes to help them to make them better and creative. The story of Jenny is also interesting because although she was disturbing teachers in school because she could not sit upright all she wanted was to dance (Robinson). However, the teachers did not see this potential or her creativity, but when the doctor realized it she made Jenny’s mum enroll her in a dance school. Education is becoming dynamic and people with degree are no longer recognized in the society as they used to and for that reason, the only thing that will help the younger generation is by becoming creative. A student enters in class to attend a lecture where they are all required to have personal computers. However, when James takes a sit she does not have any computer or any backpack to indicate that he might be carrying one. The teacher becomes furious first because he is late and second he is going to distract the other students as they share on PC. The lecturer points him out and asks him to leave. He asks the reason the teacher is asking him to leave and the teacher states that he will distract the calls if he shares the PC. He responds by removing a slim tablet from his pocket that has better features and that is more portable than the laptop. Everyone in the class is surprised and after class he show cases the features of the Tablet to the other student who in turn call the provider for a piece. Robinson, Ken. "Ken Robinson: How schools kill creativity | Talk Video | TED.com." TED: Ideas worth spreading. Rolex,  Feb.  2006. Web. 19  Nov.  2014.

Segmenting markets Essay Example | Topics and Well Written Essays - 1250 words

Segmenting markets - Essay Example Factor Analysis is a statistical tool that helps in understanding variables, or factors among the correlated and observed variables. It is mostly used to determine the variations in a larger number of groups by identifying the small number of factors within the large number of a particular group The first step is to select a method for factor analysis. There are two methods while conducting a factor analysis which are known as exploratory factor analysis and confirmatory factor analysis. Exploratory factor analysis is a technique for factor analysis which is often used for a larger set of variable. If the goal of a researcher is to identify the relationship with the measured variable then he should opt for the exploratory factor analysis. This method would help a researcher if no prior assumption or theory is made on the relation of the factors. However, in confirmatory factor analysis the variables are determined with the relation of prior assumptions or theory which aims to see if it meets the expectation as it was predicted. This method is selected when a social research is conducted. The simplification of a factor analysis is often interpreted by a method known as rotation which makes the output more understandable for the researcher. Rotation is the next step involved in factor analysis. The pattern of loadings in rotation works differently on each variable, the loading of each variable that has extracted factors are maximized while it minimizes the loading for other factors. There are five methods of rotation in which varimax, equamax and quartimax are orthogonal rotations whereas promax and direct oblimin are oblique rotations. The rotation of a particular variable mostly depends on a person if he thinks that the factors that are underlined should be related or not. If factors are considered to be independent then the author suggests that a person should use orthogonal rotation methods whereas if factors have chances to correlate then it is required to a dopt direct oblimin which is an oblique rotation (Gorsuch, 1983). Labeling a factor is the next step which is an art of segmentation in which a factor is named which best describes the particular factor. The most common and appropriate technique is to name the highly ranked or the top one or two factors on the list. It is labeled on the basis of its characteristics, for example factor one can be labeled as price conscious whereas factor two can be labeled as quality conscious (Rummel, 1970). In the final step, interpretation is been made to assess the validity of factors outlines previously. In this step, four types of validity methods are used namely, content validity, concurrent validity, predictive validity, and construct validity. Content validity intends to measure the intended or the desired area which is associated with the theme of the research. Construct validity intends to assess the factors which involve the testing of hypothesis to which the researcher was trying to meas ure. Concurrent validity is the method in which scores are correlated with some other variables and then it is justified. In predictive validity method, a test is used to determine or justifying the theoretical outcomes which were expected. These steps are used for the purpose of finding a correlation between variables (Gorsuch, 1983). 2. Cluster Analysis: Cluster analysis is a statistical technique which helps in assorting of ‘mountain’ of information into neat files by forming a cluster or a group in which variables are similar to one another. It helps in creating subgroups which becomes more manageable than previously dealing with the individual variable. Similar to factor analysis, it is used to determine the relationship of variables between other variables. The first step involved in cluster analysis is the assigning of similar variables to their respective

History 4 discussion Essay Example | Topics and Well Written Essays - 500 words

History 4 discussion - Essay Example Therefore, successful outcomes of reduced insurgence by the north and their retreat could count in indicating that US was winning the war. Hamburger Hill is one the movies that gives an account of the occurrences that took shape in the Vietnam War and relays the story from the soldiers who took part in the war. The movie shows an attempt to take Hill 937 by the US troops and the negative impact that war brings about. Other films that also give a firsthand account of the war are, Band of Brothers and Saving Private Ryan. Limited war is the opposite of total war. The war was based on ideologies of means and end. Because of constraints in terms of the resources like financial, military and human, the presence or absence of a vision played a great role in influencing the outcome of the war. The war had to be fought by any means in order to attain the desired result. The end was to justify the means. The topic describes the Vietnam War as formless and could hardly be sustained. It had crude statistics of measuring a win. Assuming that Southern Vietnam was not an excessively hard place to operate and under-estimation of the enemy, made the war possible and sustained. The Viet used Guerrilla tactics in their combat. The US soldiers, on the other hand, used the search and destroy tactics as well as bombing the economic and industrial centers of the enemy soldiers and this tactic obliterated the Viet Cong army. To describe the Vietnam war as formless and frontless, I think creates a picture of lack of military organization with no clear cut means of measuring attained success and no strategies to secure the secured enemy territory. The war had no specific objective that could be pointed out and was, thus, formless. It was hard to identify signs of victory. Fighting could take place anywhere at any time with no frontline. The Cuban missile crisis was a great threat of nuclear war in the world. The patience exhibited by J.F Kennedy helped put the

Women's Rights in Islam Research Paper Example | Topics and Well Written Essays - 2500 words

Women's Rights in Islam - Research Paper Example Social responsibility among Muslims originated from the Qur’anic scripture which says: â€Å"And [as for] the believers, both men and women—they are friends and protectors of one another: they [all] enjoin the doing of what is right and forbid the doing of what is wrong, and are constant in prayer, and render the purifying dues, and pay heed unto God and His apostle. It is they upon whom God will bestow His grace: verily, God is almighty, wise.†i The above Qur’anic verse indicates that men and women are to cooperate with one another in the educational and political sphere (they should understand God’s commandments and have an influence in society to actualize God’s wisdom), in the social sphere (helping the poor and the disadvantaged), and in the religious sphere (prayer). These required tasks mentioned in the verse reveal that both men and women are to actively take part in society instead of simply being submissive or indifferent. Participation in the political realm is a way to accomplish one’s duties to society. Political participation can be carried out in various ways, from voting, to occupying a position as a magistrate or lawmaker, to being a national leader. Islam offers examples for each of these positions, roles, and duties for women. Within the spiritual realm, Islam does not distinguish between men and women. According to the Qur’an, men and women have to fulfill the same objective—both will receive rewards or punishments based on their personal deeds, both will be tried by God, and both have an obligation to live up to their religious duties. Every time the Qur’an specifies those blessed people who will be accepted to the Garden of Bliss due to their goodness, piousness, and virtue, it cites both men and women: â€Å"And whoever does righteous good deeds, male or female, and is a (true) believer [in the Oneness of Allah (Muslim)], such will enter Paradise and not the least injustice, even to the size of a Naqira (speck on the back of

Economic growh & environmental quality (haiti vs california) Essay

Economic growh & environmental quality (haiti vs california) - Essay Example This is because unlike California, Haiti has seen numerous political and environmental shocks that have severely hindered its growth. Nevertheless, economic growth in both California and Haiti comes with negative environmental outcomes comprising water and land pollution, greenhouse gas emissions as well as destruction of ecological landscape. Haiti economic growth largely centers on agriculture given that majority of the island is mountainous. Most of Haiti lush rainforests has been cleared for small-scale farming and charcoal burning, hence leaving only 28.3% of its land mass to be good for arable and commercial farming1. Agriculture accounts for the nation 25% of its GDP production. As a result, two thirds of Haiti labor-force still lives on small-scale subsistence farms which has resulted in economic stagnation, that has made Haiti the poorest nation in the western hemisphere. Hence, the nation has no substantial industrial or manufacturing sector, which then makes 40% of Haitian population to be unemployed even as the average income for most Haitian is less than $200 per year2. Haiti economy is largely driven by informal small-medium enterprises, which accounts for 80% of the nation new jobs. Nonetheless, the textile industry forms the second largest economic activity after arable farming. On the other hand, Californ ia has a GDP per capita income of $60,190 per year with the unemployment level standing at a much lower level of 7.4%3. Secondly, California has a diverse and highly skilled workforce working in different sectors unlike Haiti, and varies from high tech, to retail and service industry, to manufacturing, biotech, entertainment, to agriculture. Thus, before the 2007-2008 financial crises, California experienced per capita GDP growth that surpassed even the United States per-capita GDP expansion. In particular, the state share of the entire California manufacturing output grew from eight to

History 4 discussion Essay Example | Topics and Well Written Essays - 500 words

History 4 discussion - Essay Example Therefore, successful outcomes of reduced insurgence by the north and their retreat could count in indicating that US was winning the war. Hamburger Hill is one the movies that gives an account of the occurrences that took shape in the Vietnam War and relays the story from the soldiers who took part in the war. The movie shows an attempt to take Hill 937 by the US troops and the negative impact that war brings about. Other films that also give a firsthand account of the war are, Band of Brothers and Saving Private Ryan. Limited war is the opposite of total war. The war was based on ideologies of means and end. Because of constraints in terms of the resources like financial, military and human, the presence or absence of a vision played a great role in influencing the outcome of the war. The war had to be fought by any means in order to attain the desired result. The end was to justify the means. The topic describes the Vietnam War as formless and could hardly be sustained. It had crude statistics of measuring a win. Assuming that Southern Vietnam was not an excessively hard place to operate and under-estimation of the enemy, made the war possible and sustained. The Viet used Guerrilla tactics in their combat. The US soldiers, on the other hand, used the search and destroy tactics as well as bombing the economic and industrial centers of the enemy soldiers and this tactic obliterated the Viet Cong army. To describe the Vietnam war as formless and frontless, I think creates a picture of lack of military organization with no clear cut means of measuring attained success and no strategies to secure the secured enemy territory. The war had no specific objective that could be pointed out and was, thus, formless. It was hard to identify signs of victory. Fighting could take place anywhere at any time with no frontline. The Cuban missile crisis was a great threat of nuclear war in the world. The patience exhibited by J.F Kennedy helped put the

Economic growh & environmental quality (haiti vs california) Essay

Economic growh & environmental quality (haiti vs california) - Essay Example This is because unlike California, Haiti has seen numerous political and environmental shocks that have severely hindered its growth. Nevertheless, economic growth in both California and Haiti comes with negative environmental outcomes comprising water and land pollution, greenhouse gas emissions as well as destruction of ecological landscape. Haiti economic growth largely centers on agriculture given that majority of the island is mountainous. Most of Haiti lush rainforests has been cleared for small-scale farming and charcoal burning, hence leaving only 28.3% of its land mass to be good for arable and commercial farming1. Agriculture accounts for the nation 25% of its GDP production. As a result, two thirds of Haiti labor-force still lives on small-scale subsistence farms which has resulted in economic stagnation, that has made Haiti the poorest nation in the western hemisphere. Hence, the nation has no substantial industrial or manufacturing sector, which then makes 40% of Haitian population to be unemployed even as the average income for most Haitian is less than $200 per year2. Haiti economy is largely driven by informal small-medium enterprises, which accounts for 80% of the nation new jobs. Nonetheless, the textile industry forms the second largest economic activity after arable farming. On the other hand, Californ ia has a GDP per capita income of $60,190 per year with the unemployment level standing at a much lower level of 7.4%3. Secondly, California has a diverse and highly skilled workforce working in different sectors unlike Haiti, and varies from high tech, to retail and service industry, to manufacturing, biotech, entertainment, to agriculture. Thus, before the 2007-2008 financial crises, California experienced per capita GDP growth that surpassed even the United States per-capita GDP expansion. In particular, the state share of the entire California manufacturing output grew from eight to

Statue of Liberty Essay Example for Free

Statue of Liberty Essay A universal symbol of democracy and freedom, The Statue of Liberty, is a gift of companionship from the France people to the United States people. The Statue of Liberty enlightening the globe was devoted on 28th October, 1886. In 1924, The Statue of Liberty was designated and selected as a National Monument. The meaning of The Statue of Liberty is Liberty Enlightening the World and is an enormous neoclassical monument in New York Harbor on Liberty Island. It was designed by the Frederic Bartholdi and it is a figure of female. The female represents the Roman Goddess of Freedom, Libertas, who puts up with a tablet inducing the law (tabula ansata) and a torch. When you look at it, I can feel it tells me a lots of things: Liberty, freedom, power to take on the world. And win. On the tabula ansata, 4th July, 1776, the American Declaration of Independence date is emblazoned. At the feet of the Statue of Liberty lies a broken chain. The Statue of Liberty is a convivial signal to the immigrants that are arriving from overseas and it is an icon of the United States and its freedom. The height of the Statue of Liberty is 151ft that is 46.5 meters and along with the pedestal the statue reaches a height of 305 ft that is 93 meters . Inside the statue there are 354 stairs that end at the crown from where a nice view of the New York is available (WHC, 2013). The Statue of Liberty Ellis Island Foundation (SOLEIF) founded by the President Ronald Reagan in 1982. This was done to start a classified division attempt to lift resources for the re-establishment and safeguarding of the Ellis Island and Statue of Liberty. The Foundation initially began the renovation of the Statue of Liberty along with the National Park Service, U.S. Department of the Interior. This was done because the statue needs refurbishment due to a century of sightseeing and weather pollution. On 4th July, 1986, a three day event was celebrated on the restoration of the statue. This weekend was also named as the â€Å"Liberty Weekend† by the President Francois and President Reagan (NPS, 2013). The Statue of Liberty is an icon and symbol of international friendship, companionship and alliance of the United States and France. It describes the liberty and freedom of the people of United States. The Statue of Liberty is an emblem of warm welcome to the people coming from overseas and abroad. To me Lady Liberty was meant to stand for the opportunity afforded to all who either came here or were born here. All that was required was the willingness to work,strive,and dream of a better day. References NPS (2013) History of the Statue of Liberty. The Statue of Liberty-Ellis Island Foundation, Inc., retrieved from http://statueofliberty.org/Statue_History.html NPS (2013) History of the Statue of Liberty. The Statue of Liberty-Ellis Island Foundation, Inc., retrieved from http://statueofliberty.org/Foundation.html NPS (2013) Statue of Liberty: National Monument New York. National Park Service: U.S. Department of the Interior, retrieved from http://www.nps.gov/stli/index.htm WHC (2013) Statue of Liberty. UNESCO World Heritage Centre, retrieved from http://whc.unesco.org/en/list/307

Chemical Engineering Innovation in Food Production

Chemical Engineering Innovation in Food Production The inherent safety, convenience, availability, nutritional content, aesthetic appeal, and variety that characterize food supplies are a hallmark of modern life. Chemical engineering knowledge can be accredited with improving the conversion of raw foodstuffs into safe consumer products of the highest possible quality. Among those, membrane-based separation and other filtration techniques are most common. Chemical engineers have applied their expertise to chemically synthesize fertilizers, herbicides, and pesticides that promote crop growth and protect crops from weeds, insects, and other pests (AlChe, 2009). Its so easy to feel the contribution of chemical engineering in food sector if we observe the morning tea to late night beverage. All processed food stuffs around us is more or less subject to different types of filtration. One of the fastest growing parts of the whole sector is the mineral water and soft drinks sector, which has a sizeable requirement for fine filtration (Suther land, 2010). Modern techniques are used to improve the flavour, texture, nutritional value, safety, appearance and overall aesthetic appeal of various foods. Modern food processing can also improve the quality of life for people with food allergies and for diabetics. Foods processed using aseptic packaging retains their vitamins, minerals, and desired textures, colours, and flavours more effectively than those processed with traditional canning. Nestlà ©, Wal-Mart, Unilever, PepsiCo etc. are some world famous food companies without whom modern life cannot be imagined. Filtration in food processing Filtration is a process where solid particles present in a suspension are separated from liquid or gas employing a porous medium (Srikanth, 2012). Surface, depth and cake filtration are different types based on filtration mechanism. Two types of filtration theory are widely known which are gas filtration theory and liquid filtration theory. These theories have also some limitations. There are some criteria for choice of filter medium such as particle size that has to removed, permeability of clean medium, solid holding capacity of the medium, flow resistance of medium etc. Filter aid is a very important factor which forms a surface deposit to screen out the solids and it also prevents the plugging of the supporting filter medium (Srikanth, 2012). Chemical engineers have invented a variety of engineered processes that allow food processors to remove impure substances to improve food quality, safety, and aesthetics. Todays membrane-based separation is used widely to remove impurities during food processing by pressure to force unwanted substances in food ingredients to pass through a semi permeable membrane and it is also applied majorly in the dairy industry, mainly as a processing phase in production soft cheeses. Chemical engineers strive to maximize the available surface area in filter, reduce membrane pore size, minimize the pressure drop the fluid will experience when flowing through the unit and maximize cost-effectiveness (AIChe, 2009). For food industries, there are some specific requirements to choose filter media such as dissipation of electrostatic charges, high abrasion resistance, available clean-in-place system etc. In this dissertation, some food processing industries have been presented where different types of filtration are the key factor. Among those cane and beet sugar industry, starch and sugar industry, beverage industries like wine, beer etc. are notable. Filtration should be the most prior subject to enhance food safety management of an industry. It can help to remove physical, chemical and other microbiological contaminants with great efficiency. This also focuses on advantages of self-cleaning filters over manual and mechanical cleaning. Advances in filtration technology include the development of continuous processes to replace old batch process technology (Patel R. et al, 2010). FOOD PROCESSING INDUSTRIES Chemical engineering innovation in food production If the grass on the other side of the fence appears greener . . . it must be all the fertilizer they are using. Kevin Rodowicz. The food industry is a complex, global collective of diverse businesses that supply much of the food energy consumed by the world population. Before modern engineering advances were widely adopted by the food industry, the variety of foods available at stores were determined by what was produced locally, since transportation limitations predicted the distance that perishable foods could travel (AIChe, 2009). Chemical engineers routinely develop advanced materials and techniques used for, among other things, chemical and heat sterilization, advanced packaging, and monitoring and control, which are essential to the highly automated facilities for the high-throughput production of safe food products (AIChe, 2009). Chemical engineering unit operations and procedures, established for other industrialized reasons, are used by the food industry like drying, milling, extrusion, refrigeration, heat and mass transfer, membrane-based separation, concentration, centrifugation, fluid flow and blending, powder and bulk -solids mixing, pneumatic conveying, and process mode ling, monitoring, and control. Among these, membrane-based separation and other filtration techniques are mostly common (AIChe, 2009). Technological milestones: Over the years, engineered solutions have increased the production of processed fruits and vegetables, dairy, meat and poultry, and seafood products, and have allowed more widespread distribution of such foods. The following are some of the most revolutionary improvements in food processing noted in the Milestones of the Twentieth Century by the Institute of Food Technologists (AIChe, 2009). 1900s: Vacuum packaging, which removes the oxygen from inside the food package, was invented to prolong the shelf life of foods, and the widespread practice of freezing foods began with fruit and fish. The first ready-to -eat cereals using many chemical engineering unit operations appeared as well (AIChe, 2009). 1920s: Fast-freezing practices for foods were first commercialized by Clarence Birdseye, whose name has become practically known with frozen foods. Birdseye found that by blanching vegetables (cooking them for a short time in boiling water) just before freezing, the process could deactivate certain enzymes that cause off-colours and off-flavours, thereby enhancing the quality of the thawed vegetables. The first commercial use of puffing to produce such cereals as Cheerios and puffed rice also began (AIChe, 2009). 1930s: Freeze-drying processes were pioneered in this decade, and frozen foods are dried after deep freezing, in which the entrained water is removed by a process known as sublimation by heating the frozen product in a vacuum chamber. Freeze-dried foods in turn become shelf-stored foods that quickly regain their original flavour, aroma, size, shape, and texture after rehydration. The removal of water slows spoilage, thus providing longer shelf life, and reducing the weight of the food, which makes it cheaper and easier to transport (AIChe, 2009). 1940s: The advent of automated processes to concentrate, freeze, and dehydrate foods enabled a greater variety of foods to be mass-produced and packaged for shipment overseas to military personnel during World War II. Disease-free packaging extremely improved food quality, safety, and nutrient retention (AIChe, 2009). 1950s: During this era, monitored-atmosphere packaging using plastic increased the shelf life of fresh foods. The process controls oxygen and carbon dioxide levels inside the packaging environment to reduce respiration by fruits and vegetables (similar to human breathing) and reduces the amount of off-gas ethylene produced, which delays maturing and damage (AIChe, 2009). 1960s: The first commercial-scale producing machine began producing cold-dried foods and coffee. Advances in aseptic processing allowed shorter heating times for sealed food containers (AIChe, 2009). 1970s: The period of the 1970s saw growing usage in the chemical process industries (paint, textile, oil recovery, pulp and paper). In this decade, the major effects of this technology is in the food and biotechnology processing industries, where ultrafiltration and cross-flow microfiltration are finding increasing uses as a gentle and efficient way of fractionating, concentrating and clarifying a variety of food from milk products, fruit juices and alcoholic beverages to fermentation broths, protein fractions and wastewaters (Cheryan M, 1986). 1980s: Advanced-atmosphere packaging began to be used widely during this era and It is a more progressive difference of controlled-atmosphere packing, in which the head space atmosphere within a food package or the transportation/ storage vessel is modified by flushing it with a blend of inert (nonreactive) gases (AIChe, 2009). 1990s: High-pressure processing was commercially applied first to fresh packaged foods to kill microorganisms that cause spoilage without altering flavours, texture, or appearance (AIChe, 2009). After 2000: Recent food trends are actually based on fat calculation but tasty, healthy and doctor-designed. Different types of cupcakes, cheese, pizza, fast foods etc. are peoples first choice. Also various types of grain made foods are getting popularity day by day (AIChe, 2009). Advances in chemical fertilizers, herbicides, and pesticides Early mankind experimented with human and animal wastes, seaweed, ashes and other substances to fertilize crops and increase productivity. Chemical engineers have applied their expertise to chemically synthesize fertilizers, herbicides, and pesticides that promote crop growth and protect crops from weeds, insects, and other pests. Today, the use of these products is more important than ever to meet the needs of an ever-expanding population (AIChe, 2009). Fertilizers Nitrogen is the most plentiful part of the air we breathe, present at 79% by volume and a prime nutrient (most often in the form of ammonia). Modern fertilizers stem from a chemical engineering breakthrough pioneered by Fritz Haber in 1908 that developed a process to synthesize ammonia by reacting hydrogen with nitrogen and in 1918, he was awarded the Nobel Prize in Chemistry for this discovery (AIChe, 2009). Working with industrialist Carl Bosch, Haber scaled up the successful Haber-Bosch process that allows ammonia to be produced cost-effectively in commercial quantities for use in nitrogen fertilizers. Habers original reaction was carried out under high pressures. The improved ammonia synthesis process carries out the reaction at lower pressures and temperatures, which helps save money by reducing the amount of energy required by the process (AIChe, 2009). Pesticides and herbicides Chemists and chemical engineers have also been helpful in the discovery, synthesis and commercial-scale manufacture of various chemical compounds that are used as pesticides (to kill insects) and herbicides (to kill weeds). For example, chemical engineers discovered that when glyphosate (the primary ingredient in Monsantos widely used herbicide Roundup) is applied to a crop, it inhibits a specific growth enzyme called the EPSP synthase. Glyphosate is rapidly metabolized by weeds, and unlike many other earlier herbicides, it binds tightly to soil so that it does not accumulate in runoff to contaminate surface waters or underground aquifers. According to its manufacturer, it eliminates more than 125 kinds of weeds, but does not affect mammals, birds, fish, or insects (AIChe, 2009). Advanced food processing techniques Today, imaginative and effective engineered approaches many drawn directly from the chemical engineers toolbox routinely add nutrients, improve aesthetic appeal (in terms of a foods flavours, texture, and appearance), enable longer distance transport (leading to multi-seasonal availability), extend shelf life, and remove microorganisms that contribute to spoilage and are responsible for food-borne illnesses. Modern food processing can also improve the quality of life for people with food allergies (by removing or neutralizing the proteins and other substances that create allergic reactions in certain people) and for diabetics (by reducing sugar content and providing sugar-free alternatives). The roasting of coffee beans requires exceptionally precise control of the chemical and physical reactions over time. Depending on the progressive bean temperature experienced during roasting, final flavours characteristics can vary widely. Chemical engineers have devised ways to make timely adjustments to the roaster to moderate airflow rates and manipulate bean temperatures without changing the flavours (AIChe, 2009). Sterilizing and packaging perishable foods Sterilization is a key aspect of any food -packaging operation. The ability to sterilize foods to protect them against spoilage by oxidation, bacteria, and moulds has always presented an important engineering challenge. Throughout history, people have experimented with the use of dehydration, smoking, salting, pickling, candying and the use of certain spices. They include high-temperature pasteurization and canning, refrigeration and freezing, chemical preservatives (using such compounds as sulphite, sodium nitrite, ethyl formate, propionic acid, sorbic acid, and benzoic acid), and irradiation (AIChe, 2009). Pasteurization In the early years, no one knew how Nicolas Apperts process preserved foods successfully, but the ability to can foods meant that Napoleons army fighting a long way from home could be fed properly and safely and that British sailors could maintain a healthier diet by feasting on fruits, vegetables, and meats while on long voyages overseas. More than 50 years later, Louis Pasteur (1822-1895) explained the mystery by proving that the growth of microorganisms is the primary cause of food spoilage and food -borne illnesses and that a high percentage of them could be killed by heating liquids to about 130 °F (55 °C) or higher, for relatively short periods, without altering the chemical makeup of the food. This simple process became known as pasteurization and was quickly and widely adopted (AIChe, 2009). Aseptic packaging First introduced in the U.S. in the early 1960s, it provides major advantages over traditional canning. It allows many products once considered perishables such as milk and juice to be packaged, distributed, and stored for months or longer without the need for refrigeration, irradiation, or chemical preservatives. In general, during aseptic packaging, both the food and packaging are sterilized at high temperatures for very short periods (AIChe, 2009). The original technology superheated steam to sterilize cans. Pressurized heat exchangers and holding tubes allows the foods and beverages to be sterilized at around 300 °F. Foods processed using aseptic packaging retains their vitamins, minerals, and desired textures, colours, and flavours more effectively than those processed with traditional canning. In 1989, aseptic-packaging technology was voted the food industrys top innovation of the last 50 years by the Institute of Food Technologists (AIChe, 2009). Some world famous food companies In terms of corporate size, food manufacture has no companies to match the giants of other sectors (Sutherland, 2010). Although still by far the largest of the food producers, Nestlà ©, with annual sales in 2009 of about $95 billion (well down on 2008), is only a quarter of the size of the largest petroleum companies such as Exxon or Shell (Sutherland, 2010). (There are, of course, food retailers much larger than Nestlà ©, especially Wal-Mart whose 2009 sales of $400 billion made it the third largest company in the world in terms of turnover, with Carrefour a long way behind at second in the list of retailers, at $130 billion (Sutherland, 2010). The next largest company classified as a food producer is Unilever, with total 2009 sales of $53 billion (although the Unilever picture is complicated by its extensive range of non-food household goods businesses) (Sutherland, 2010). Unilever is closely followed by Cargill, the largest private company in the USA, and by Archer-Daniels-Midland, although both of these are large natural product commodity dealers as well. Then come ConAgra, Kraft Foods, Danone, Kellogg, General Mills, and H J Heinz (Sutherland, 2010). For some time, the leading beverage companies have been the soft drink makers Pepsico (2009 sales of $43 billion) and Coca Cola ($32 billion), some distance ahead of the brewers (Sutherland, 2010). This picture changed in 2008 with the purchase of Anheuser-Busch by InBev (itself the fairly recent merger of Interbrew and AmBev) to create a company larger than Coca Cola (although still behind Pepsi) and second in size of the brewers is now SABMiller (a 2002 creation), followed by Heineken and then Carlsberg (Sutherland, 2010). Further consolidation in the beverage sector is being driven by a search for markets, because beer drinking can be very regional. Thus, Heineken has acquired the beer business of Femsa in Mexico which holds 40% of its domestic market and nearly 10% of that in Brazil and one of the fastest growing parts of the whole sector is the mineral water and soft drinks sector, which has a sizeable requirement for fine filtration (Sutherland, 2010). FILTRATION Definition Filtration is a process whereby solid particles present in a suspension are separated from the liquid or gas using a porous medium, which retains the solid but, allows the fluid to pass through. It is a common operation used widely in sterile products, bulk drugs and in liquid oral formulation. The suspension to be filtered is called slurry. The porous medium used to retain the solids is known as filter medium and the accumulated solids on the filter are referred as filter cake and the clear liquid passing through the filter is filtrate (Srikanth, 2012). The pores of the filter medium are smaller than the size of particles to be separated. When feed is passed over the filter medium, the fluid flows through it by virtue of a pressure differential across the filter. Gravity is acting on the liquid column; the solids are trapped on the surface of the filter medium. After a particular point of time, the resistance offered by the filter cake is high that stops the filtration (Sambhamurthy , 2005). Types of filtration Based on the mechanism, there are 3 types of filtration which are surface filtration, depth filtration and cake filtration. Surface filtration It is a screening action by which pores or holes of the medium prevent the passage of solids. For this purpose, plates with holes or woven sieves are used (Matteson, 1987). An example is a cellulose membrane filter. Depth filtration This filtration mechanism retains particulate matter not only on the surface but also at the inside of the filter. It is extensively used for clarification. Ceramic filters and sintered filters are examples of depth filtration (Stephan, 2003). Case study of depth filtration (Carey, 2008): Several forces have driven changes in filtration technology during the last few decades, including environmental concerns, the health and safety of winery employees and wine quality. The major active component in traditional depth filtration is diatomaceous earth, which has several major problems. First, it is difficult to dispose because it does not decompose. Second, it can cause symptoms similar to coalminers black lung disease when inhaled over long periods of time. To overcome these drawbacks, cross flow filtration and ultra-filtration are being practiced in recent years. Cross flow filtration: It ranges between ultra-filtration and reverse osmosis and the nominal pore size of the membrane is typically below 1 nanometer (Wikipedia, 2012). Nano filtration membranes are still subject to scaling and fouling and often modifiers such as anti-scalants are required for use (Hillie, 2007). Ultra filtration: It is a pressure driven membrane transport process that has been applied on both the laboratory and industrial scale. It is becoming a powerful separation tool for the rapidly growing biotechnology industry (Goldsmith et al., 1974). Cake filtration By this mechanism, the cake accumulated on the surface of the filter is itself used as a filter. A filter consists of a coarse woven cloth through which a concentrated suspension of rigid particles is passed so that they bridge the holes and forma bed. Theory of filtration Depending on dispersing medium filtration theory is divided in two parts; Gas filtration Liquid filtration Gas filtration theory It mainly includes filtration of aerosols and lyosols. There are several mechanisms for this theory. They are as follows (Wilson Cavanagh, 1969). Diffusion deposition The trajectories of individual small particles do not coincide with the streamlines of the fluid because of Brownian motion. With decreasing particle size the intensity of Brownian motion increases and, as a consequence, so does the intensity of diffusion deposition. Direct interception This mechanism involves the finite size of particles. A particle is intercepted as it approaches the collection surface to a distance equal to its radius. Inertial deposition The presence of a body in the flowing fluid results in a curvature of the streamlines in the neighbourhood of the body. Because of their inertia, the individual particles do not follow the curved streamlines but are projected against the body and may deposit there. It is obvious that the intensity of this mechanism increases with increasing particle size and velocity of flow. Gravitational deposition Every particle has a definite sedimentation speed due to gravity. As a consequence, the particles deviate from the streamlines of the fluid and owing to this deviation; the particles may touch a fibre. Electrostatic deposition Both the particles and the fibres in the filter may carry electric charges. Deposition of particles on the fibres may take place because of forces acting between charges or induced forces. Liquid filtration theory The term solid-liquid filtration covers all processes in which a liquid containing suspended solid is freed of some or the entire solid when the suspension is drawn through a porous medium (Melia Weber, 1972). Kozeny Carman equation = . (1) Here, A = filter area V = total volume of filtrate delivered t = filtration time à ¢Ã‹â€ Ã¢â‚¬  P = pressure drop across cake and medium r = specific cake resistance  µ = filtrate viscosity l = cake thickness L = thickness of cake equivalent to medium resistance (Skilling, 2001). Limitations: This equation does not take into account of the fact that depth of the granular bed is lesser than the actual path traversed by the fluid. The actual path is not straight throughout the bed, but it is sinuous (Chowdiah et al., 1981). Poiseulles law This Law considered that filtration is similar to the streamline flow of a liquid under pressure through capillaries. = . (2) Cake resistance, RM = . (3) Specific cake resistance, ÃŽÂ ± = ÃŽÂ ±Ãƒâ€" ³Ãƒ ¢Ã‹â€ Ã¢â‚¬  P. (4) The filter resistance is much less than the cake resistance (RC Filter media The filter medium acts as a mechanical support for the filter cake and it is responsible for the collection of solids (Srikanth, 2012). Minimum cake thickness of discharge for different types of filter is presented in Table 1 (Subramanyam et al., 2005). Table 1: Minimum cake thickness for discharge (Andrew et al., 2002) Filter type Minimum design thickness Belt 3.0-5.0 Roll discharge 1.0 Standard scraper 6.5 Coil 3.0-5.0 String discharge 6.5 Horizontal belt 3.0-5.0 Horizontal table 19.0 Materials used as filter media (Rushton, 2008) Different types of materials used as filter media for various applications industrially and domestically are presented in Table 2. Table 2: Type of filter media, features and their application (Patel R. et al, 2010). Type of filter media Features Application