The Stages Of The Refrigeration Cycle Engineering Essay

The Stages Of The Refrigeration Cycle Engineering Essay The second law of thermodynamics is described as the most fundamental law of science (Khemani, 2008). It is fundamental in the sense that it can be used to explain not only refrigerators and heat engines but highly advanced phenomena such as the big bang. It has been put aptly in the words of Classius as it is impossible for a process to occur that has the sole effect of removing a quantity of heat from an object at a lower temperature and transferring this quantity of heat to an object at a higher temperature (Mortimer, 2008). This essentially means that heat cannot flow spontaneously from a cooler to a hotter body if nothing else happens (Mortimer, 2008) i.e. there needs to be an external agency to effect the change. In kitchen refrigerators, the closed box inside is able to be kept cool by the removal of heat from the inside of the box and depositing it on the outside. Because the heat will not move freely from the cold inside to the hot outside, as by the second law, it is important for it to be made to do so, this is done by using an intermediate fluid (Littlewood, 2004) which absorbed heat on the inside. This intermediate fluid is known as a refrigerant and carries the heat outside of the box whereby it it released into the air as heat as shown in (Littlewood, 2004). Figure 1 the flow of heat within the refrigerator a schematic (Littlewood, 2004) The fluid circulates within the pipe which passes in and out and can be found at the back of the refrigerator. It is kept by using a compressor (which uses electricity from the home) and allows it to work effectively without violating the second law of motion. (Littlewood, 2004) THE FIRST LAW Refrigerator takes in energy from a region that needs to be cooled (or kept cold) and deposits this heat energy into some other region that is outside of the refrigerator. In order to work, there has to be some mechanism in place, where the work done by a compressor and its electric motor is utilized. Using the First Law of Thermodynamics we can write: (Littlewood, 2004) Figure 2 the first law of thermodynamics (Littlewood, 2004) QC   QH  = -W Where: Qc energy or heat of the cold system QH = energy or heat of the hot system W = work done Since work is done on the refrigerator by another device (the compressor), rather than by the refrigerator itself, the work is done is deemed negative because of sign conventions. This is part of the first law (Littlewood, 2004). Suppose that 2.4 MJ of work is used to remove 5.2 MJ of heat from the inside of the refrigerator, then an amount of heat QH  = QC  + W = 5.2 MJ + 2.4 MJ = 7.6 MJ must be added to the kitchen. The refrigerator is termed as a closed system and it possesses a constant composition: U = U + (à ¢Ã‹â€ Ã¢â‚¬Å¡U/à ¢Ã‹â€ Ã¢â‚¬Å¡V) T dV U = U + (à ¢Ã‹â€ Ã¢â‚¬Å¡U/à ¢Ã‹â€ Ã¢â‚¬Å¡T) V dT U = U + (à ¢Ã‹â€ Ã¢â‚¬Å¡U/à ¢Ã‹â€ Ã¢â‚¬Å¡V) T dV + (à ¢Ã‹â€ Ã¢â‚¬Å¡U/à ¢Ã‹â€ Ã¢â‚¬Å¡T) T dT dU (à ¢Ã‹â€ Ã¢â‚¬Å¡U/à ¢Ã‹â€ Ã¢â‚¬Å¡V) T dV + (à ¢Ã‹â€ Ã¢â‚¬Å¡U/à ¢Ã‹â€ Ã¢â‚¬Å¡T) V dT According to Bain (2010), there are four basic parts to any refrigerator: Compressor Heat Expansion valve Refrigerant The exchanging pipes are a coiled set of pipes that is placed strategically outside of the unit. The refrigerant as will be discussed later on is a liquid that has the ability to evaporate efficiently so that inside the refrigerator is kept cooled. (Bain, 2010) A gas can be cooled by adiabatic expansion if the process is enthalphic. The gas expands through a process barrier from one constant pressure to the next and the temperature difference in observed. Insulation of the system made the process adiabatic. The result is that a lower temperature was absorbed on the on a low pressure side and the change in the temperature is proportional to the change in pressure. (Bain, 2010)  Ã¢â‚¬Å¾T  µ  Ã¢â‚¬Å¾P Figure 3 schematic of a domestic refrigerator (Bain, 2010) When an energy |qc| is removed from a cool source at some temperature Tc, and then deposited in a warmer sink at a temperature Th, the change in entropy is: (Atkins dePaula, 2006) Atkins dePaula (2006) also indicated that the process is not spontaneous because the entropy generated in the warm sink is not enough to overcome the loss of entropy from the cold souce. And because of this more energy needs to be added to the stream that enters the warm sink to generated the entropy required by the system. They further indicated that the outcome is expressed as the coefficient of performance, c: The less the work required to achieve a given transfer, the greater the coefficient of performance and the more efficient the refrigerator (Atkins dePaula, 2004). Because |qc| is removed from the cold source, the work |w| is added to the energy stream, the energy deposited as the heat in the hot sink |qh| = |qc| + |w|. Therefore, From: We can have an expression in terms of the temperature alone, which is possible if the transfer is performed reversibly (Atkins dePaula, 2006): Where: c = thermodynamic optimum coefficient of temperature Tc = temperature of the cold sink Th = temperature of the hot sink For a refrigerator, it important that a very low coefficient of performance. For a refrigerator withdrawing heat from ice cold water (Tc = 273 K) in a typical environment (Th = 293K), c = 14. As an example, to remove 10 kJ (enough to freeze 30 g of water), requires transfer of atleast 0.71 kJ as work. (Atkins dePaula, 2005) The work to maintain a low temperature is very important when designing refrigerators. No thermal insulation is perfect, so there is always some form of energy flowing as heat into a specific sample at a rate that is proportional to the temperature difference. (Atkins and de Paula, 2006). Figure 4 (a) the flow of energy as heat from a cold source to a hot sink is not spontaneous. As can be seen, the entropy increase of the hot sink is smaller than the entropy increase of the cold source, so there is a net decrease in entropy (Atkins dePaula, 2006). (b) The process becomes feasible if work is provided to add to the energy stream. Then the increase in entropy of the hot sink can be made to cancel the entropy of the hot source (Atkins dePaula, 2006) he rate at which energy leaks happen is written as: Where: A = a constant that depends on the size of the sample and details of the simulation Tc = temperature of the cold sink Th = temperature of the hot sink The minimum power, P, required to maintain the original temperature difference by pumping out that energy by heating the surroundings is: As can be seen the power increases as the square of the temperature difference (Th Tc). THE REFRIGERATION CYCLE The gas is pumped continuously at a steady pressure, the heat exchanger (which brings the required temperature) and then through a porous plug inside container that is thermally insulated. A phase change heat pump uses a liquid that has a low boiling point to transfer heat from a cooler area to a warmer one, in refrigerators. This heat pump is the most commonly used in domestic refrigerators. It employs a liquid, known as a refrigerant which has a low boiling point. The liquid requires energy (called latent heat) to evaporate, and it drains that energy from its surroundings in the form of heat. When the vapor condenses again, it releases the energy (in the form of heat). A refrigerant is a compound used in a heat cycle that undergoes a phase change from a gas to a liquid and back. Latent heat describes the amount of energy in the form of heat that is required for a material to undergo a change of phase (also known as change of state). Two latent heats are typically described. (Bamb ooweb, 2009)For other uses, see CFC (disambiguation). The pump operates a cycle in which the refrigerant changes state from its liquid form to the vapour form and vice versa. This process occurs repeatedly and I known as the refrigeration cycle. In this cycle, the refrigerant condenses and heat is released in one point of the cycle. It is the boiled (or evaporated) so that it absorbs heat in another point of the cycle. The widely used refrigerant is hydro fluorocarbon (HFC) known as R-134a (1, 1, 1, 2 tetrafluoroethane) and CCl2F2 (dichlorodifluoromethane). Other substances such as liquid ammonia, propane or butane, are be used but because of their highly flammable nature, they are disregarded as a good refrigerant. 1930 (MCMXXX) was a common year starting on Wednesday (link is to a full 1930 calendar). (Bambooweb, 2009)For other uses, see CFC (disambiguation). In the refrigerator the fluid used (e.g. CCl2F2 ) fluid is liquefied by compression then vaporized by sudden expansion which gives a cooling effect. The compressor, in itself does not create a cooling effect directly, as might be expected. The cooling effect is created when the refrigerant absorbs the heat from the cooled space. This is accomplished with a heat exchanger. (Bambooweb, 2009)For other uses, see CFC (disambiguation). A heat exchanger is a device built for efficient heat transfer from one fluid to another, whether the fluids are separated by a solid wall so that they never mix, or the fluids are directly contacted. The refrigeration cycle can be divided in two parts: The liquefaction stage The evaporation stage LIQUEFACTION STAGE The refrigerant vapour undergoes recycling by itself into the liquid form by the extraction of heat from a vapour at a higher temperature. The refrigerant is compressed by the compressor where a low pressure and low temperature condition is created. This is accomplished by an evaporating coil. During the compression process, the vapour of the refrigerant undergoes a temperature change (as an effect of the compression process). Additionally, the work of compression to create the high temperature and pressure vapour also contributes to the temperature change experienced by the vapour. The condenser that is located where the temperature is higher (i.e. the higher temperature heat sink) collects the vapour. Heat is then removed from the refrigerant and in lieu of this it condenses to its liquid state, hence the name for the condenser. Using the Joule-Thompson coefficient: For a perfect gas  µ = 0 Cp + Cv = (à ¢Ã‹â€ Ã¢â‚¬Å¡H/à ¢Ã‹â€ Ã¢â‚¬Å¡T)p (à ¢Ã‹â€ Ã¢â‚¬Å¡U/à ¢Ã‹â€ Ã¢â‚¬Å¡T)p Introducing: H = U + pV = nRT into the first term: Cp Cv = (à ¢Ã‹â€ Ã¢â‚¬Å¡U/à ¢Ã‹â€ Ã¢â‚¬Å¡T)p + nR (à ¢Ã‹â€ Ã¢â‚¬Å¡U/à ¢Ã‹â€ Ã¢â‚¬Å¡T)p = nR EVAPORATION STAGE As the refrigerant leaves the condenser, the next part of the cycle begins. This is accomplishe when a high temperature and high pressure liquid passes through a metering device that is found within the refrigeration. The valve allows a specific quantity of liquid coolant to pass into the evaporation chamber. Evaporation chambers are relatively low pressure and this encourages coolant evaporation. Newly evaporated coolant is drawn though the cooling coils (typically a fan is used to blow air over the coils). Thus, the evaporative process produces the cooling effect. The refrigerant then is pulled to the compressor in the suction line where it will be compressed into a high temperature, high pressure gas and sent to the external heat sinking coils. Capillary action or capillarity is the ability of a narrow tube to draw a liquid upwards against the force of gravity. A refrigerator pumps heat up a temperature gradient. The cooling efficiency of this operation depends on the amount of heat extracted from the cold temperature reservoir (the freezer compartment), , and the work needed to do so. Since a practical refrigerator operates in a cycle to provide a continuous removal of heat, for the cycle. Then, by the conservation of energy (or first law), , where is the heat ejected to the high temperature reservoir or the outside. The measure of a refrigerator performance is defined as the efficiency expressed in terms of the coefficient of performance (). Since the purpose is to extract the most heat () per unit work input (), the coefficient of performance for a refrigerator, , is expressed as their ratio: Where, the conservation relationship given above is used to express the work in terms of heat. For normal refrigerator operation, the work input is less than the heat removed, so the is greater than 1. Refrigerators are commonly referred to as heat pumps of more specifically a it is a reversible heat pump because they basically pump heat. Figure 5 A simple stylized diagram of a heat pumps vapor-compression refrigeration cycle: 1)  condenser, 2)  expansion valve, 3)  evaporator, 4)  compressor. Opening a food refrigerator or freezer heats up the kitchen rather than cooling it because its refrigeration cycle rejects heat to the indoor air. This heat includes the compressors dissipated work as well as the heat removed from the inside of the appliance. The COP for a heat pump in a heating or cooling application, with steady-state operation, is: Where: ΆQcool is the amount of heat extracted from a cold reservoir at temperature Tcool, ΆQhot is the amount of heat delivered to a hot reservoir at temperature Thot, ΆA is the compressors dissipated work. EFFICIENCY The efficiency of a refrigerator (known as the coefficient of performance, COP) is defined as   For example, if 20 MJ are removed from the inside of the refrigerator by doing 7.5 MJ of work, then the coefficient of performance is equal to 20/7.5 = 2.67. SUMMARY OF THERMODYNAMIC OF A REFRIGERATOR AFTER ONE CYCLE Change in internal energy = 0 Change in heat is > 0 Total work > 0 Total volume change = 0 Change in Gibbs free energy = 0 Entropy change of the system = 0 Entropy change of the universe > 0

Communication task

British sign language which is a specific sis language that is used in Britain, the use of megaton, which is a simplified verse n of the British sign language that is used for children or those with disabilities or the use of signs, symbols, pictures, writing and finger spelling which gives a person that I s unable to talk or hear an effective way to communicate with friends, family and career believe that interpersonal interactions are just as important as any other method of communication this is because the way interpersonal interactions are used ca determine many things within a conversation e. . If you have poor body langue age like crossed legs and playing with a pen it suggests that you are not paying attention n and you are not interested in what the other person is saying. Will now explain the e role of effective communication and interpersonal interactions within two scenarios. Scenario 1 Alfa will not leave his room after accusing other residents in a residential home for stealing his money before the career found this money in Alfa pocket.The care r would have to communicate with Alfa to help the situation as a one to one context to encourage Alfa to feel comfortable as he may not feel comfortable talking about the situate ion when other residents or careers are present because he may feel embarrassed. As Alfa is a welsh speaker a career that has the ability to speak welsh should b allocated to talk to Alfa to prevent any language barriers that may arise. This WI II be a formal conversation between professional and a person using the service.The career will have to use oral communication as it is the most effective WA y to gain an immediate response and to be able to show your emotion such as using b DOD language. Body language is an important nonverbal interpersonal interaction because it can show another person our emotions e. G. If you are moving around and lo king away lot it can suggest you are not interested in what they are saying and also it c an be altered to gain another trust and to ensure they feel comfortable.The career would have to speak in a respectful manner towards Alfa and adder sees his collect to be able to communicate effectively e. G. It is disrespectful to speak to your elders with slang unless you know them very well because it may offend them or they may simply not understand a youths slang such as ‘alright lad' they don't ACTA ally mean that they are talking to a male its a nickname for a friend or someone they anAlfa has a hearing problem so he wears a hearing aid which is a technological al aid to communication however even with the hearing aid the career should use a Simi plea lexis and speak clearly so that he can understand, the career should also be facing A If so that the career's voice is projected towards him more efficiently. The career would have to use nonverbal interpersonal interactions by shows Eng a positive posture which consists of not crossing your arms and legs. By showing g this positive posture the career is showing Alfa that they are interested in his though TTS and feelings of the situation.The career would also use reflective listening by asking g Alfa questions to empower him. Facial expressions are read when a face to face conversation is taking place so the career should ensure that they have a gyms atheistic and caring facial expression to encourage Alfa to talk about the way he feels, the e career should ensure that they do not have an angry or happy facial expression became use this might suggest to Alfa that the career is annoyed with him or finds the situation f noun which may encourage Alfa to feel uncomfortable and anxious.Following the meeting the career should use written communication to log t e situation down into a book such as an incident book, so that if needed to the information on is there permanently so it can be reviewed. The career could also use technological communication by Emailing or testing the main career to inform the m of the sis tuition that has occurred because tech analogical communication is the most effective way if you need to inform someone of something and do not need an immediate response Scenario 2 Rosier is a young women who is terminally ill, she informs the career that she re ally wants to leave hospital to go home.The career would have to communicate with Rossi e and Rookie's family within a group context, this will be because as Rosier deteriorate s her family would be held responsible to care for her as well as a district nurse. The career would have to use technological communication to contact a doctor or that can inform Rosier and her family of all the effects that can occur if Rosier is to g o home. Rosier would have to communicate with a professional to find out whether she can go home and if so what precautions should be taken.Different professionals would have to work together to try meet the needs f Rosier which is multidimensional working, this can include Rookie's caree r, a doctor an d a counselor working together to see if it is suitable for Rosier to go home. The career should empower Rosier by encouraging her to tell the career why s he wants to go home, the career could use silence while Rosier is talking because the pop e r Of silence is significant however at the same time the career should be using facial expressions and body movement to show that they are listening.The career c loud place her hand on Rookie's shoulder to communicate through touch, this shows that he career is understanding and is trying to comfort Rosier. 2 As Rosier has a different dialect to the career because she is from different r colon Rosier pronounces words differently and also uses different words and phrase s e. G. Rosier is originally from London and has the cockney accent, the cockney ace changes a lot of words e. . The English word hair they change to Barnett, the c are would have to listen attentively to ensure that she does not misunderstand what Or sis IS s aying. Rookie's counselor suggests that she could use arts and crafts to release her negative motions as arts and crafts are known as therapeutic activities which are often n used with children and adults that have mental health Illnesses to boost their moo d.As Rookie's condition deteriorates she may become unable to communicate effectively through oral communication so the career should teach her different signs and symbols to use to communicate, signs and symbols are very helpful for people that ca not communicate orally or people that simply do not want to because of a condition on such as selective mutatis, they can use these signs and symbols so that the people AR undo them can understand what they want to say or need.There are many different aspects to being able to communicate effectively and most of them are used in our everyday lives e. G. Communication forms such as text messaging are used all the time to connect with our friends and family. After explaining the role of e ffective communication and interpersonal interaction in a health and social care context it shows just how important effective communication is to be able e to be understood.Effective communication is important because without it patients wouldn't e able to receive the care that they need because of poor or no communication interpersonal interactions are also important so that the emotion behind ha t a person is saying is not misunderstood. 3 PA Discuss theories of communication will be discussing two theories of communication one as a that applies to a o en to one context and the other as a group context. Jean's theory assists in giving effective communication to patients, this once auroras the patient to trust the caregiver.Jean's theory (1986) consists of a technique called ‘SOLES and each letter h s a different step in order to communicate effectively. Jean's theory can only be used in a one to one context however it can be formal or informal. The ‘S' is for sitting at a comfortable distance and angle, the ‘O' is for open p suture, the ‘L' is for leaning,looking and listening the ‘E' is for effective eye contact and the ‘ R' is for remaining relatively relaxed.A situation that is suitable for this theory would be a General Practitioner TA King to their patient, this is suitable because it is a situation where the context is one to on e and it is formal. A GAP would use the ‘SOLES' technique from the moment their patient walks through the door, they should be sitting at the right angle which is head on to the patient and they should be sitting at a comfortable distance not too close and not too far away because e the patient may feel that they are not important if they are sat far away however they ma y feel intimidated if the GAP sits too close to them.They should sit with an open posture with their arms and legs uncrossed to prevent the patient from feeling that the GAP is uninterested. They shouldn't put anything I n between themselves and the patient e. . A table, a cup Of coffee/ tea because this may give the impression that they are putting a physical barrier in between a professional and a user of the service which can cause the patient to feel they do not want to have a connect ion with the GAP leading to the patient not telling the GAP what their problem is.When a GAP is talking to their patient they should lean forward every now an d then, they should look as if they are genuinely interested and listen attentively all these s tepees empower the patient which should encourage the patient that they can take control Oft e conversation supporting their confidence. A GAP should use effective eye contact when communicating to a patient to ensure the patient knows the GAP is listening to them which should be done by looking at the but not staring, however if the patient has a condition such as anxiety this may make them feel uncomfortable and anxious.The GAP should remain relaxed and talk w ith a calm and almost sympathetic voice throughout the session so that the patient does not become panicked however re if the patient becomes aggressive the GAP should talk in an assertive voice and try to diffuse he situation encouraging patient to calm down. Jean's theory would also be effective when a counselor is talking to their p tenant however it wouldn't be effective at a work meeting because this is within a group and Egg Nan's theory is for a one to one context. Barnyard's theory is used within groups and could be formal or informal. It works by noticing the dynamics within a group and preventing or encouraging them. Barnyard's theory could be used at a daycare centre because this is a group. In the group some children have been attending for a long time and some may be new, so the children that eve been there longer have had chance to bond and get to know each other whereas the newer children may not want to be there and may try to be destructive toward ads the discussion s or just too shy to bond with others.

Occupational and Environmental Pesticide Exposure and the Risk of Alzheimers Disease - Free Essay Example

Sample details Pages: 8 Words: 2355 Downloads: 9 Date added: 2019/04/12 Category Medicine Essay Level High school Tags: Alzheimer's Disease Essay Did you like this example? This literature review discusses the possible connection between pesticide exposure and the risk of developing Alzheimers disease (AD). After thorough examination of peer-reviewed and literature review articles, data revealed there is an association between the risk of Alzheimers disease and pesticide exposure, primarily limited to those with a history of occupational pesticide exposure. Only brief evidence of environmental pesticide exposure and risk of Alzheimers disease was found. Don’t waste time! Our writers will create an original "Occupational and Environmental Pesticide Exposure and the Risk of Alzheimers Disease" essay for you Create order While each article touched on the aforementioned topic, the literature also emphasized the importance for supplementary research on specific pesticide classes, as results indicated organophosphates and organochlorines pose the most significant risk in developing Alzheimers disease. The literature presented distinctly called to action further research on this connection primarily in female populations, as the link between pesticide exposure and risk of Alzheimers disease in males is more apparent. Further study on this topic may include new research examining pesticide usage in food products, as eating pesticide-altered foods is a mechanism of everyday pesticide exposure in both genders, not yet explored in literature. If this research is conducted, there is potential for change in overall pesticide usage, policies on pesticides, and possible reduction in cases of Alzheimers disease. Keywords: pesticides, pesticide exposure, occupational, environmental, Alzheimers disease, risk factors, neurological disorders Pesticide Exposure and the Risk of Alzheimers Disease There is long-standing evidence that pesticides can be responsible for certain acute and chronic health effects. Although there are thousands of studies on pesticides and their link to conditions such as cancers, reproductive health, and Parkinsons disease, data is lacking in regards to pesticide exposure and their relationship to the risk of developing Alzheimers disease (AD). Current findings suggest pesticide exposure may cause the loss of neuron signaling, resulting in cognitive decline, impaired memory/attention, and motor function, all of which are common neurobehavioral symptoms of AD (Baldi et al., 2003, Parrin, Requena, Hernandez, Alarcin, 2011). Databases such as PubMed and ScienceDirect were used to find peer-reviewed articles that applied to this topic between the years 2001 and 2014. Mesh headings included risk of AD, risk factors for AD, occupational pesticide exposure, and environmental pesticide exposure. The majority of literature that surfaced pertaining to pestici de exposure and its association with increased risk of AD consisted of cohort, case-control, and ecological studies, with a focus on populations where occupational or environmental mechanisms were the origins of exposure. This paper discusses the current evidence on the association between daily occupational and environmental pesticide exposure and the risk of developing AD by examining five peer-reviewed articles and one literature review. The presented literature highlights how risk of AD may differ between occupational and environmental pesticide exposures, specific types of pesticides and possible elevated risks of AD, as well as explanations representing the lack of data on pesticide exposure and risk of AD in female populations. Literature Review Occupational and Environmental Pesticide Exposures The factors distinguishing occupational pesticide exposure from environmental pesticide exposure include the intentional, direct usage of pesticides by a person during their daily occupation, typically in farming and agricultural industries (Quissell, 2018). Conversely, environmental pesticide exposure may include the unintentional contamination of soil, water, air, and vegetation from pesticides (Quissell, 2018). For the purposes of this review, the latter is considered independent from occupational pesticide exposure. A prospective cohort study published in The American Journal of Epidemiology reported a significant association between AD and occupational pesticide exposure, explaining that the French elderly, aged 65 and older, who previously worked in vineyards or agricultural settings had over two times the risk of developing AD due to their occupation (Baldi et al., 2003). It is also important to emphasize this positive association still occurred after adjusting for smoking and education levels (2003). By the last follow-up session, researchers found a cumulative exposure for a total of 228 subjects, twenty-six of whom presented with AD, translating to 30.7 cases per 1,000 person-years (Baldi et al., 2003). This study suggests that not only may short-term cognitive impairments occur in occupationally exposed individuals, but AD development is also a possible and more severe result of occupational pesticide exposure, even after long-term work cessation (Baldi et al., 2003). A more recent case-control study published in The American Academy of Neurology explained similar conclusions on occupational pesticide exposure and the risk of AD. After assessment of self-reported exposure data and cognitive statuses in residents of Cache County, Utah, researchers concluded that of the 572 pesticide-exposed individuals, over 40% of those exposed reported farming as their primary occupation (Hayden et al., 2010). More importantly, 344 of the pesticide-exposed individuals were all diagnosed with AD (2010). These results provide evidence that there is a correlation between occupational pesticide exposure and development of AD. However, this correlation also poses the argument that pesticide exposure outside of occupational settings and risk of AD is also possible, as not all of the 344 pesticide-exposed individuals reported exposure from only occupational history. This latter statement is evidence suggesting that in general, pesticides could be an overall risk factor in developing AD. Although data seems consistent in occupational pesticide exposure and risk of AD, the two studies that evaluated the association between environmental pesticide exposure and risk of AD differed immensely. In a case-control study developed in the Saguenay-Lac region of Quebec, Canada, researchers aimed to find an association between environmental pesticide exposure and risk of AD, basing their conclusions on assessment of pesticide, herbicide, and insecticide spraying activity in residential areas (Gauthier et al., 2001). After controlling for genetic, occupational, and sociodemographic factors, the results failed to show a connection between significant risk of AD and exposure to any and all pesticides (2001). In a literature review published in Toxicology, authors consider the outcome of Gauthier et al. (2001) invalid, as the central measure of environmental exposure was indirectly assessed based on residence and the Agriculture Statistics of Canada for pesticide-spraying activity i n only a few areas (Zaganas et al., 2013, p.6). Conversely, an ecological study conducted in Andalusia, Spain, provides some evidence that the risk of AD is in fact greater in populations living near farm and agricultural lands where there is high pesticide usage (Parrin, Requena, Hernndez, Alarin, 2011). Parin, Requena, Hernndez, Alarcn (2011) explain how pesticide residues can travel into surrounding water, soil, and even air from nearby agricultural land and farms, becoming a harmful substance to those in proximity (p.380). This concept is one mechanism of environmental pesticide exposure, and a potential reason why populations living in areas of high pesticide usage have a greater risk of AD (Parr?n, Requena, Hernandez, Alarcin, 2011). This data is particularly significant for the association between environmental pesticide exposure and risk of AD because researchers controlled for all occupations relating to agriculture. Therefore, data only represented participants exposed to pesticides based on proximity to agricultural practices and farmlands, compared to those who lived closer to urban settings. In other words, results propose that there is an association between environmental pesticide exposure and higher risk of AD, independent from occupational exposure. Although Gauthier et al. (2001) did not provide evidence of an association between environmental pesticide exposure and risk of AD, it is important to note that this study is an example of the clear-cut gap in current literature on environmental pesticide exposure and the risk of AD itself. Further research strictly on environmental pesticide exposure and the risk of ADis crucial to provide a consensus in data. This research should answer if environmental pesticide exposure includes more categories in addition to contamination of soil, water, air, and household pesticides. Research should call into question if duration of environmental pesticide exposure has an effect on the risk of AD, if certain classifications of pesticides have a higher risk than others in comparison to widely used occupational pesticides, as well as possible ways to eradicate environmental pesticide exposures. Types of Pesticides and Elevated Risk of AD Part of the difficulty in determining if pesticide exposures are truly associated with risk of AD is the lack of science-based evidence regarding the harmful effects of specific pesticide classes. Media, news outlets, and even documentaries about the agricultural industry have instilled the idea that the four classes of pesticides are not created equal, and some are far worse than others. According to science-based literature, there is some truth to this statement, as research suggests two specific pesticides, organophosphates and organochlorines, statistically show a correlation in the risk of developing AD (Hayden et al., 2010, Richardson et al., 2014). Before its official ban in 1972, the organochlorine DDT, was one of the most widely used pesticides in U.S. agriculture (Richardson et al., 2014). The knowledge of DDT persistence in the environment and its ability to accumulate in tissues over a long period of time led researchers at The Robert Wood Johnson Medical School at Rutger s University to examine serum levels of patients with AD who previously had an occupational history of DDT exposure (Richardson et al., 2014). Results indicated that serum levels of DDT were significantly elevated in 80% of their patients with AD, which suggests organochlorines may have a greater effect in the risk of developing AD over other classes of pesticides (2014). In the Cache County case-control study, questions during assessment of exposure addressed four specific types of pesticides including organophosphates, carbamates, organochlorines (DDT), and methyl bromides (Hayden et al., 2010). Results identified that of the 572 individuals who reported pesticide exposure, 316 reported exposure to organophosphates, 256 to organochlorines, 28 to methyl bromides, and 25 to carbamates (2010). Aside from organophosphates and organochlorines being the two pesticides participants were numerically most exposed to, data revealed that participants who were exposed to organophosphates had the highest risk of AD (53% higher), with organochlorines posing only slightly less risk (Hayden et al., 2010, p.1528). Unlike most of the data that grouped all pesticide classes together, both Richardson et al. (2014) and Hayden et al. (2010) called attention to which types of pesticides may significantly increase the risk of AD. It is important to draw the connection between these two studies, for their findings promoted the hypothesis that toxicity levels in pesticides are variable based on classification. Although these two studies point to clear evidence suggesting exposure to organophosphates and organochlorines pose greater risks in developing AD, further research is necessary to determine levels of toxicity across all classes of pesticides and possible synergistic effects. Pesticide Exposure and AD in Males versus Females Across the literature, data suggests most pesticide exposure occurs in male-dominated occupational settings, making the association between pesticide exposure and the risk of AD extremely prevalent among males (Hayden et al., 2010). Despite female participant inclusion at the origin of all studies, researchers clearly emphasized there was no significant association of occupational pesticide exposure and risk of AD in females, (Baldi et al., 2003, p.413-14). Furthermore, it was also determined that males living in areas with high pesticide usage showed nearly double the risk of presenting with AD in comparison to females (Parr?n, Requena, Hernndez, Alarc?n, 2011). This trend reveals that males seem to have a higher risk in developing AD through both occupational and environmental pesticide exposures. The largest gap across literature is relevant data on female pesticide exposure and the risk of AD. This is ironic considering AD in general disproportionately affects older female populations (Zaganas et al., 2013). In Zaganas et als. (2013) literature review, researchers emphasized that of the fourteen studies assessed, the majority of research failed to include reasoning as to why there may be a difference in male versus female pesticide exposure and risk of AD (Zaganas et al., 2013). Researchers attribute some lack of data to the sheer fact that research on AD development itself is still underway, whereas data on other neurological diseases, such as Parkinsons, are more readily available and extensive (Zaganas et al., 2013). Conclusions and Future Study Through close examination of the literature, concrete evidence displayed the risk of AD increased for those with a history of occupational pesticide exposure. However, the conclusions in studies that examined environmental pesticide exposure and the risk of AD were far less clear. Some literature emphasized the danger in specific pesticides such asorganophosphates and organochlorines, but most studies failed to draw attention to which pesticides may have caused a more severe connection in the risk of developing AD. Moreover, it was apparent that not only is overall data on this topic still minimal, but data on female pesticide exposure and risk of AD is almost non-existent. Baldi et al. (2003) and Gauthier et al. (2001) failed to communicate speculations as to why there was no significant association in female populations, while Richardson et al. (2014) disregarded gender, and classified his participants only by occupational exposure. Further research on the link between pesticide ex posure and risk of AD must include a way of measuring exposure that is generalizable across a majority of populations. Initiative in examining pesticide-altered foods, provided by agricultural and food industries, is one way to achieve new data solely on environmental pesticide exposure, specific pesticide toxicity classifications, and statistical differences in both genders, as eating pesticide-altered foods is a mechanism of daily pesticide exposure not yet explored in literature. References Baldi, I., Lebailly, P., Mohammed-Brahim, B., Letenneur, L., Dartigues, J. F., Brochard, P. (2003). Neurodegenerative diseases and exposure to pesticides in the elderly. American Journal of Epidemiology, 157(5), 409â€Å"414. https://doi.org/10.1093/aje/kwf216 Gauthier, E., Fortier, I., Courchesne, F., Pepin, P., Mortimer, J., Gauvreau, D. (2001). Environmental pesticide exposure as a risk factor for Alzheimers disease: A case-control study. Environmental Research, 86(1), 37â€Å"45. https://doi.org/10.1006/enrs.2001.4254 Hayden, K. M., Norton, M. C., Darcey, D., stbye, T., Zandi, P. P., Breitner, J. C. S., Welsh-Bohmer, K. A. (2010). Occupational exposure to pesticides increases the risk of incident AD: The Cache County Study. Neurology, 74(19), 1524â€Å"1530. https://doi.org/10.1212/WNL.0b013e3181dd4423 Parrin, T., Requena, M., Hernandez, A. F., Alarcin, R. (2011). Association between environmental exposure to pesticides and neurodegenerative diseases. Toxicology and Applied Pharmacology, 256(3), 379â€Å"385. https://doi.org/10.1016/j.taap.2011.05.006 Quissell, K. (2018, March 15). Pesticides. [PowerPoint slides]. Retreived from https://learn.bu.edu/webapps/portal/execute/tabs/tabAction?tab_tab_group_id=_10_1 Richardson, J. R., Roy, A., Shalat, S. L., Von Stein, R. T., Hossain, M. M., Buckley, B., German, D. C. (2014). Elevated serum pesticide levels and risk for Alzheimer disease. JAMA Neurology, 71(3), 284â€Å"290. https://doi.org/10.1001/jamaneurol.2013.6030 Zaganas, I., Kapetanaki, S., Mastorodemos, V., Kanavouras, K., Colosio, C., Wilks, M. F., Tsatsakis, A. M. (2013). Linking pesticide exposure and dementia: What is the evidence? Toxicology, 307(May), 3â€Å"11. https://doi.org/10.1016/j.tox.2013.02.002

Physician-Assisted Suicide The Law and Professional Ethics - Free Essay Example

Sample details Pages: 4 Words: 1152 Downloads: 2 Date added: 2019/05/31 Category Law Essay Level High school Topics: Assisted Suicide Essay Did you like this example? The discussion to make physician-assisted suicide legal has created mixed reactions among the US citizens. Despite its ethical prohibitions, some people continue to express their interest in the act. People have increasingly shown their concerns and fears regarding how their lives will end. Don’t waste time! Our writers will create an original "Physician-Assisted Suicide: The Law and Professional Ethics" essay for you Create order Some people have voiced out their opinions on euthanasia, and surprisingly, a section of them continue to advocate for the legalization of the process. Others have expressed their disgrace in the debate surrounding legalization of the process as it is against the ethical code of living. As a result, the American College of Physicians (ACP), continue being attentive to all concerns raised by people. It makes sense that patients suffering from some terminal, painful illnesses and patients from tragic accident experience a lot of pain and some may prefer death to life. Cases of this type lead to a debate on whether physicians should be allowed to terminate life. In a society where the laws of land give everyone a right to life, a discussion about whether people have the right to end their lives under whichever conditions have attracted divergent views among citizens. Although it is the wish of most people to live long and enjoy life, some life situations like excessive pain after an accident or a long severing resulting from terminal diseases may make life unbearable forcing some people to prefer death to life. As a result, most Americans are concerned whether on whether dying patients have the right to acquire assistance from a physician (Emanuel et al. 78) The debate has drawn its fair share of critics as against work ethics for the physicians and patients who subscribe to the belief that one has the right to die peacefully should have their concerns addressed (Battin and Margaret P 67). However, before the rights of such citizens are treated, difficulties posed the procedure should be discussed. For instance, it has proven quite hard to control euthanasia. Whatever the case, the decision to grant terminally ill patients the right to euthanasia should be considered. Patients autonomy should be respected, and the argument that is aiding patientrs sickness is in line with the role of a physician to relieve pain and suffering in ailing people. It is argued that allowing physicians aide in the death of a pertinent is a breach of their ethical traditions. Although it is quite understanding as the traditional physicians work ethics are centered in caring and protecting patients lives, the wish of the patient should be granted (Quill et al. 246). The suffering of dying patients may be unbearable as a result of nausea, extreme pain and other physiologic conditions like anxiety and depression (Emanuel et al. 80). In such circumstances, some patients prefer to be given the freedom of timing the time of their demise. Medical assistance to such patients should be checked. Similarly, the role of medicine to relieve pain through induced death under patients wish should be considered. The main subject in euthanasia debate should be the patient and not the physician. The possibility of people taking advantage of the right to physician-assisted death is still a significant concern. Sometimes people undergoing solvable problems in life such as stress resulting from family and marriage conflicts and tough economic times may choose death over living. The rights to euthanasia should be limited to conditions of extreme pain and possibly long time coma and severe memory loss. Measures prohibiting people from taking advantage of medically and physically and psychologically solvable problems should be put in place. Such an action can bring order and prevent people from taking power. The decision to end life should be exclusively left to patients to avoid cases of ill-fated physicians killing eternally ill patients in life supporting machines and intensive care units (Battin and Margaret P 70). Patients expressing the will to euthanasia should have their conditions examined to determine their fate. For instance, patients suffering from some diseases or in stages of illness can be advised appropriately upon medical cross-examination. Should such patients choose euthanasia, their wishes can be granted. A judge named Stephen Reinhardt backed the claims whether anyone has the right to assisted suicide in the United States. When presented with the case whether any person has the right to euthanasia, Judge Reinhardt ruling stated that any adult person who has lived almost all his/ her life has the paramount liberty to select a civil and humane death instead of being subjected to a natural diapered state when if they are terminally ill. This was one of the landmark rulings that defends aided suicide. People should therefore not be subjected to severe suffering by denying them the right. Human beings suffering from terminal illnesses have rights just as healthy people and should be not be subjected to inhuman suffering when they can choose to end their lives peacefully. Nonetheless, terminating life should not be the case in the United States. Continued improvements in medicine have produced drugs capable of treating severe human pain. Although medicine may not address some conditions today, future advanced in the area may come up with such medications. Additionally, society should learn to give people nearing the end of their lives good care both emotionally and physically. A 1997 research in the United States by IOM about approaching death found out that there was insufficient end-of-life care in the country. Research from proceeding years has backed up the claims. Cases of patients receiving poor or no care at all during their weak moments are quite familiar. The society should learn to give adequate care and support to their ailing and terminally suffering people. Adopting such a culture would reduce the number of people seeking aided death. The observation that most people worry about how they will die should be looked in to keenly. Americans should consider subscribing to programs that take care of people in their end of life moments. Disease prone and ailing older adults should be moved to nursing homes where they can receive quality care and diet in their dying moments (Quill et al. 245). Americans should also prioritize palliative care which takes care of terminally ill people and families. People should be encouraged to plan for palliative care programs which would take care of their conditions in case they become terminally ill. Finally, research in the United States has documented the elderly and people who have cancer as prone to subscribing to euthanasia drugs. For instance, research in Oregon State in 2014, established that 69% of people taking lethal medication had cancer while 68% of all those taking the drugs were above the age of 65 years. From the findings, the government and the society should increase their support care and compassion to such groups of people. Aided death should be used severe critical conditions of acute suffering and for elderly people with terminal illnesses. The country revises physician-aided suicide law and sets in combat regulations to allow terminally-ill people choosing euthanasia death path enjoy their right.