Compare and Contrast Vertebrate and Invertebrate Vision Essay Example

Compare and Contrast Vertebrate and Invertebrate Vision Paper Although vertebrates and invertebrates originally evolved from a common ancestral root, both have developed very different physical utilities for vision. Both are fairly effective and have taken many millions of years to evolve. They contain many common underlying mechanisms but differ in the features used to provide them. The definition of an eye is an organ of visual perception that includes parts specialized for optical processing of light as well as well as photoreceptive neurons (Alberts). The main feature of an eye therefore, in all organisms that possess one, is the collection of photoreceptors used in converting light energy into action potentials (electrical energy). When comparing vertebrate and invertebrate vision, the two best-studied cases are the compound eye exemplified by arthropods and the simple eye used in vertebrates. The main difference between the compound and simple eye is that the compound eye uses a spatial array of lenses so that each image in a local region of visual space falls onto one or a few photoreceptors. The simple eye, however, uses a single lens to image the world onto an array of photoreceptors. Compound eyes produce mosaic images. The compound eye is made up of many optical units called ommatidiums, each of which is aimed at a different part of the visual field. Each ommatidium samples a different part of the visual field through a separate lens. In a simple eye, each receptor cell samples part of the field through a lens shared by all receptor cells. In compound eyes, each ommatidium samples an angular cone-shaped portion of the environment, taking in about 2-3i of the visual field. We will write a custom essay sample on Compare and Contrast Vertebrate and Invertebrate Vision specifically for you for only $16.38 $13.9/page Order now We will write a custom essay sample on Compare and Contrast Vertebrate and Invertebrate Vision specifically for you FOR ONLY $16.38 $13.9/page Hire Writer We will write a custom essay sample on Compare and Contrast Vertebrate and Invertebrate Vision specifically for you FOR ONLY $16.38 $13.9/page Hire Writer In contrast, each receptor of a simple eye may sample as little as 0. 2i of the visual field. In addition, the simple eye, inverts the image that falls on the retina. Since the receptive field of each ommatidium is relatively large, compound eyes have lower visual acuity than simple eyes. The mosaic image formed by a compound eye is also coarser than that of a simple eye. The simple eye in vertebrates focuses incident light in two stages. In the initial stage, incident light rays are refracted as they pass through the clear outer surface of the eye, called the cornea. They are further refracted as they pass through a second structure, the lens, and finally form an inverted image on the rear internal surface of the eye, the retina. Objects at different distance can be focussed in higher vertebrates by changing the curvature and thickness of the lens, which affects its focal length, the distance at which an image passed through the lens comes into focus. Diffraction is a property of all light and because of this, the angular resolution (resolving power) of any eye is limited by the diameter of its lens. The larger the lens diameter, the higher spatial resolution. The biggest problem for compound eyes is that the resolution is limited because the facets of the individual lens are so small. A compound eye of a given size will have a much lower resolving power than a simple eye of the same size. Optical superposition compound eyes are one way of increasing the effective lens diameter. This structure works by using several separate elements to image incident rays onto a single point, such as a single photoreceptor. This method is used in insects such as fireflies. Another way, is to use neural superposition. Simple eyes on the other hand, use a single lens, and have evolved entirely separately in the cephalopods and vertebrates. The octopus is a good example because the optical design of its eyes is remarkably similar to the vertebrate eye. The one major difference, however is that in octopus eyes, as in all fish eyes, the lens is much more powerful because it has to compensate for the loss in refractive power from the cornea, due to being underwater. Simple eyes have a much larger lens diameter which means that the spatial resolution achievable is much higher than is ever possible with a compound eye. Experiments by Kirschfeld have suggested that in order to obtain the same spatial resolution as a human eye, a compound eye would need to be about 1m across. The eye is a complex structure which has caused many arguments between evolutionary biologists and theologists. Theologists believe that the eye is so perfectly designed to harvest light, and that no intermediary design would be effective, that it must have been created by a divine designer. Biologists believe that it was created step-by-step through natural selection, and that any one step is always an improvement on the last, and thus the eye did not have to be this complex to be of benefit. This argument can be backed up by the evidence of optical diseases in which humans are handicapped in their sight, yet to them, the vision they have is better than none at all, as was a primitive form of an eye. Myopia (short-sightedness) and hypermetropia (long-sightedness) occur when the optical image of a point at infinity (i. e. he far point) falls respectively in front of or behind the retina. These errors commonly occur when the eyeball is too long, or too short, and is easily corrected with a concave or convex lens. These diseases are commonly found amongst the elderly who no longer have such deformable lens and so have difficulty varying the curvature of the lens, and thus focussing on objects at different distances effectively. This is an accommodation problem. Accommodation (discovered by Helmholz) is brought about by the ciliary body that acts on the zonular fibres that support the lens. It contains circumferential (circular) muscle fibres that allow it to act as a sphincter. The lens can be dilated by relaxing the circumferential fibres, and is said to be unaccommodated. The radial fibres of the ciliary body also act by pulling outwards on the zonular fibres that support the lens, thereby thinning it. The lens is accommodated when the circumferential fibres contract, and the lens is forced to shrink. The tension in the zonular fibres is reduced, and the lens is allowed to relax into a thicker, more curved shape, with greater refractive power. A related neuronal mechanism produces binocular convergence, in which the left and right eyes are positioned by the ocular muscles so that the images received by the two eyes fall on analogous parts of the two retinas, regardless of the distance between the object and the eyes. When an object is close, each of the two eyes must rotate towards the middle of the nose; when an object is far away, the two eyes rotate outward from the midline. Photoreceptors transduce photons of electromagnetic radiation from the visible light spectrum, into electrical signals that can be interpreted by the nervous system. The energy of the electromagnetic radiation varies inversely with its wavelength, and we perceive this variation in energy as variation in colour. The outermost layer of the vertebrate retina includes two classes of photoreceptor in vertebrates: rods and cones. There are about 100 million rods in the eye and 5 million cones. A small central area called the fovea, is densely packed with cones, but in the periphery, rods outnumber cones by 20:1. Cones function best in bright light and provide high resolution, whereas rods function best in dim light but provide much less resolution. In humans, cones mediate colour vision, and rods mediate achromatic vision. These different properties are used to expand the visual capabilities of animals living in certain conditions. For example, animals that live in flat, open environments such as rabbits, usually have horizontal regions within the retina that contain a high density of cones. This concentration of cones is called the visual streak. This region corresponds to the horizon in the visual world and is thought to confer maximal resolution in this part of the scene, allowing the animal to interpret shapes on the horizon with great precision. A receptor current exists for all sensory receptors which are usually modulated by the stimulus. In the case of vertebrate photoreceptors, the light stimulus actually reduces the circulating current, by causing the closure of ion channels. Although both invertebrates and vertebrates have eyes containing photoreceptors, they differ in their structure. Vertebrate receptor cells contain a segment with an internal structure similar to that of a cilium. This cilium connects the outer segment, which contains the photoreceptive membranes to the inner segment, which includes the nucleus and mitochondria. The photoreceptors of many invertebrates lack the ciliary structure that connects the inner and outer segments of vertebrate rods and cones and the lamellae and or stacks of disks containing visual pigment. Instead, the visual pigment is located in the microvilli formed by the plasma membrane, and these pigment-containing microvilli are organised into rhabdomeres. Visual pigments consist of 2 major components: a protein (opsin) and a light-absorbing molecule (either retinal or 3-dehydroretinal). Opsins are protein visual pigment molecules consisting of 7 transmembrane ? -helix domains. Opsins are coupled to photopigment molecules that are structurally altered by the absorption of photons, and in turn modify the opsin protein. The retinal molecule assumes two sterically distinct states in the retina. In the absence of light, the opsin and retinal are linked covalently and retinal is in an 11-cis formation. The covalent bond allows this light-absorbing molecule to act as a powerful antagonist. On capturing a photon, the retinal isomerises into the all-trans configuration, initiating a series of changes in the visual pigment, as the molecule is rendered enzymatically active. When light hits the photopigment, an intermediate metharhodopsin II forms that activates the G-protein transducin. Transducin activity closes Na+ channels and the receptor cell hyperpolarizes. Activated rhodopsin is hydrolysed spontaneously to retinal and rhodopsin which is hydrolysed spontaneously to retinal and opsin which are both used repeatedly. Studies made on the horseshoe crab, Limulus polyphemus have revealed a lot about vision. The crab has paired lateral compound eyes as well as five simple eyes: medial and lateral pairs on the dorsal surface and a single unpaired simple eye on the ventral surface. The compound eyes are typical compound eyes whereas the simple eyes are similar in structure to the simplest eye known, which consists of a shallow open pit lined with photoreceptor cells that are backed by screening pigment. Each ommatidium of a compound eye contains several photoreceptor cells. The photoreceptor cells of the Limulus compound eye are located at the base of each ommatidium. Each ommatidium lies beneath a hexagonal section of an outer transparent layer, the corneal lens. Visual transduction takes place in 12 retinular, or photoreceptor, cells. Each retinular cell has a rhabdomere, a part of the cell in which the plasma membrane is thrown into densely packed microvilli, making this the part of the cell that captures light energy. The microvilli greatly increase the surface area of the plasma membrane, which increases the probability that incident light will be captured by the rhodopsin molecules embedded in the membrane. Together, the 12 rhabdomeres of the retinular cells make up a rhabdome, which surrounds the dendrite of an afferent neuron, the eccentric cell. Depolarisations of the plasma membrane can be recorded in the retinular cells when the eye is exposed to very dim light. These quantum bumps increase in frequency as the light intensity increases (i. e. as more photons impinge on the receptors). The bumps are electrical signals generated as a result of the absorption of individual quanta of light. How can capture of a single photon lead to rapid release of so much energy? In this case, through a cascade of chemical reactions inside the cell that includes G-protein activation. Activation of the G-protein cascade occurs by diffusional contact between activated rhodopsin and molecules of G-protein, which are activated sequentially, as explained above; the activated g-protein in turn activates an effector enzyme, the PDE (phosphodiesterase); this is a 1:1 step, i. e. it has no amplification. A second stage of amplification occurs because the activated PDE is an enzyme which catalyses the destruction of cGMP. The net effect is to open ion channels, allowing cations to enter the cell. In Limulus, the receptor current through the light activated channels is carried by Na+, K+ and some Ca2+. This current causes a depolarising receptor potential. When the light goes off, the channels close again, and the membrane repolarises. The sensitivity of individual photoreceptors drops with exposure to light. This light adaptation is thought to be mediated by Ca+ ions, which enter the cells when light causes ion channels to open and which by some mechanism then reduce the current through light-activated channels. Although the Limulus eye is simple compared to that of invertebrates, the visual system is capable of generating electrical activity that parallels some of the more sophisticated features of human visual perception. The crab does however lack the degree of colour perception seen by the human eye, because it lacks the short and long wave colour pigments in its cones. It is interesting to see how two totally different mechanisms of visual perception can be so different yet interrelated in many ways, and that they have involved independently to perform the same function.

Social Factors Contributing to the Juvenile Crime

Social Factors Contributing to the Juvenile Crime Free Online Research Papers One of the most notable causes of juvenile delinquency is fiat or the findings that a juvenile is delinquent by the juvenile court system without any trial, and the findings are only probable cause. Many states have laws that have less harsh treatment of juvenile delinquents than adult treatment. In return, the juvenile surrenders certain some of their rights such as a right to trial by jury, the right to cross-examine, and even the right to a speedy trial. Notable writings by reformers show that very few juvenile delinquents actually broke any law. Most were simply rounded up by the police after some event that possibly involved criminal action. They were brought before juvenile court judges who said they were delinquents, simply because the police on duty established probable cause (Wikipedia). Its clear many experts can give us many theories as to the causes of juvenile delinquency, including ones economic background, substance abuse, delinquent peer groups, repeated exposure to violence, increased availability of firearms and media violence. However, I feel that the number one cause of juvenile delinquency is the breakdown of families, including lack of parental control over children. It is ironic in America, today, one must have a drivers license to operate a vehicle, a permit to own a gun and even a license to own a dog, but one does not have to have training or a license in order to become a parent. Without specialized educational programs in child development and parenting, many of our future parents will not have a chance at becoming successful parents and many parents today are already contributing to the ever-increasing problem of juvenile delinquency simply by not knowing how to be parents. Being a parent is a lifelong commitment and new parents must learn parent ing skills immediately. they do not have the luxury of internships some mistakes in parenting will have drastic effects on the child. There are many reasons for the widespread crisis in families today. Changes in the Social Environment, there have been many changes in our social environment over the last twenty-five years. These changes have made a risky environment for todays youth. Juvenile delinquency incorporates not only general criminal activity but conduct that is only unlawful for youths such as running away from home and skipping school. Current research into this difficult and pressing issue reflects a vast range of theories about, and predictors of delinquency as well as several strategies to control and reduce overall delinquency. The consensus among practitioners and researchers however maintains that juvenile delinquency is a dynamic, multifaceted problem with numerous potentially causal factors. Investigators and professionals suggest that treatment procedures must focus on not only the immediate issue of the offenders deviant behavior but on every element within the context of that behavior as well, including family relations and social support services. Conventional practice has been associated with early preventive measures with positive delinquency reduction results. In particular at-risk youth and correction of minimally effective parenting techniques are critical to the prevention of future delinquency (Lundman, 1993). Numerous risk factors have been identified as indicators or predictors of juvenile delinquency and those factors represent dysfunction at several levels, specifically within the structure of the offenders family. Statistics on violent juvenile crime Reasons for Juvenile Crime One of the biggest problems, which the United States is faced with, is juvenile crime. The reason experts feel juvenile’s commit crimes is because of risk factors when they were younger but experts still have not found the main reason why juvenile’s commit crimes. Some risk factors associated with juvenile crime are poverty, repeated exposure to violence, drugs, easy access to firearms, unstable family life and family violence, delinquent peer groups, and media violence. Especially the demise of family life, the effect of the media on the juveniles today, and the increase of firearms available today have played a big role in the increase of juveniles crimes. The most common risk factor is the demise of the family life and the increase in family violence. Between 1976 and 1992 the number of juveniles living in poverty grew 42% and this caused an increase in crimes by juveniles. Many of these juvenile criminals have been abused or neglected and they also grew up in a single-parent household. Research has found that 53% of these children are more likely to be arrested, and 38% more likely to commit a violent crime as an adult, then their counterparts who did not suffer such abuse. The symptoms of child abuse are â€Å"high levels of aggression and antisocial behavior† and these children are twice as likely to become juvenile offenders. Also improper parental care has been linked to delinquency such as mothers who drink alcohol or take drugs during pregnancy cause their babies to grow up with learning disorders, a problem which leads them to be juvenile criminals. Another risk factor is the effect of the media on the juveniles of today. Before the time a child has reached seventh grade, the average child has witnessed 8,000 murders and 100,000 acts of violence on the television. There is no doubt that heavy exposure to televised violence is one of the causes of aggressive behavior, crime and violence in society. Television violence affects youngsters of all ages, of both genders, at all economic levels, and all levels of intelligence. Long-term childhood exposure to television is a casual factor behind one half of the homicides committed by juveniles in the United States. Television violence affects youngsters of all ages, of both genders, at all economic levels, and all levels of intelligence. Long-term childhood exposure to television is a casual factor behind one half of the homicides committed by juveniles in the United States. The increased availability of guns has played a big part in escalating the number of crimes committed by juveniles. In Los Angeles juvenile delinquency cases involving weapon violation grew by 86% from 1988 to 1992, which was more then any other type of juvenile offense. According to a University of Michigan study found that 270,000 guns accompany secondary school students to class daily. This is startling because it shows how many more juveniles are carrying guns and the juvenile use of guns in homicides has increased from 65 to 80 percent from 1987 to 1991. The possession of firearms plays a big cause in the delinquency of children and is playing a bigger role in the crimes which juveniles commit. Another cause of the increase of juvenile crimes has been the effect of children seeing multiple murders and other acts of violence on the television. Finally the demise of the family life and the increase in family violence has been the biggest factor in the increase of juvenile crime. Most of the youth who commit violent crimes or re offend do not have a strong family bond. This is what makes it easy for this particular youths to find that family life in gangs, and criminal circles. There needs to be more programs focused on rehabilitating the family and not just the child. There are many programs to assist in the efforts to help the family. Programs like Parent-Child Integration Training Program, recreation, and something a simple as therapy for the child as well as the parents. Issues surrounding violent juvenile crime The surge in youth crime and violence caused major problems society. Various groups public and private undertook the mission of trying to uncover the reasons juvenile crime was on the rise. Lawmakers responded by toughening existing laws and finding ways to try more juveniles as adults. Courts gave out stricter sentences, and parents and educators looked into various programs and methods geared to help their children and students deal with the situation. BALA, N. (2008). An historical perspective on family violence and child abuse: Allegations of Family Violence, 12 June 2007. Journal of Family Studies, 14(2/3), 271-278. Retrieved from Academic Search Premier database J J Wilson; J C Howell (1993). COMPREHENSIVE STRATEGY FOR SERIOUS, VIOLENT, AND CHRONIC JUVENILE OFFENDERS. Retrieved from US Dept of Justice Office of Juvenile Justice and Delinquency Prevention United States Turney, K., Harknett, K. (2010). Neighborhood Disadvantage, Residential Stability, and Perceptions of Instrumental Support Among New Mothers. Journal of Family Issues, 31(4), 499-524. Retrieved from SocINDEX with Full Text database. R Lundman (1993).Prevention and Control of Juvenile Delinquency en.wikipedia.org/wiki/ Juvenile delinquency Wikipedia, the free encyclopedia retrieved(n.d.) Research Papers on Social Factors Contributing to the Juvenile CrimeThe Relationship Between Delinquency and Drug UseEffects of Television Violence on ChildrenRelationship between Media Coverage and Social andInfluences of Socio-Economic Status of Married MalesUnreasonable Searches and SeizuresPersonal Experience with Teen PregnancyPETSTEL analysis of IndiaStandardized TestingCapital PunishmentQuebec and Canada

PICOT question Assignment Example | Topics and Well Written Essays - 500 words

PICOT question - Assignment Example re incorrect markings, there was poor communication between the nurses and the doctors, poor teamwork, and there was miscommunication on whether it is the patient’s right or left limb that was to be amputated. In this particular situation the type of question that suits the given nursing situation is the intervention question. This kind of medical question considers a particular intervention or issue and compares it to a standard intervention or issue with regard to the effect that it will have on the population over a given period of time (Melnyk & Fineout-Overholt, 2015). In this instance, since time is not a critical factor, the analysis and search will only consider the population, the intervention , the standard comparison issues and the expected or possible outcome. These three elements ,therefore, need to be determined for the right information to be obtained from the completed PICO question (Melnyk & Fineout-Overholt, 2015). As indicated earlier, the question in this nursing situation will have four vital elements, which are necessary to allow for the execution of an effective and informative search. The population in this case is that of patients who visit various healthcare facilities for surgical operations. This is the group that has been identified to be at risk of the concerns raised. The intervention (issue) here is the use of schedule forms when preparing patients for the surgical operations. The third element for the case is the comparison intervention. From the summary of the nursing situation, it is evident that the staff at health facility relied on markings made using a pen to be able to know the body part that was to be operated on and the identity of the patient. Therefore, the comparison issue is the use of pens to carry out this marking. The final element is the outcome. In this case, it is the reduction in the number of erroneous operations. The reduction is measurable since it only re quires noting the number of operations without

Older people Essay Example | Topics and Well Written Essays - 1250 words

Older people - Essay Example Decisions in providing care in an abused elderly are often based on the principles of autonomy and beneficence – what the client wants and what will promote good care. Based on autonomy, abused clients have the right to respect, informed consent, and self-determination. If a competent abused client decides not to do anything about the situation, client’s decision must be upheld. On the other hand, healthcare professionals are put into a dilemma where beneficence, in an abusive situation, is needed. Healthcare professionals’ follows the principle of doing good and preventing evil harm thus, weighing between the ethical principles of autonomy and beneficence puts care interventions into a dilemma. Legal interventions and criminal charges also apply to an abusive situation. The Charter of Residents Rights and Responsibilities under the Aged Care Act of 1997 explicitly states that â€Å"people living in aged care homes in Australia have the right to be treated with dignity and respect, and to live without exploitation, abuse or neglect†. Physical, sexual, and financial abuse is very obvious and that abuse can be reported promptly while psychological abuse and neglect are less easily determined. Verifications from a multidisciplinary team or a health professional are needed to prove psychological abuse or neglect. Legal interventions could involve revoking power of attorney arrangements, taking out a domestic violence order, or having the perpetrator evicted from the older person’s premises.  ... Specific factors identified are fast history of a fall, age, female gender, lower extremity weakness, balance problems, low levels of physical activity, cognitive impairment, psychotropic drug use and polypharmacy, chronic medical problems (stroke, arthritis, Parkinson’s Disease), sensory loss, orthostatic hypotension, acute health problems (pneumonia, urinary tract infections), dizziness, diabetes, depression, and incontinence (Nay, 2009, p. 192). Incidence The incidence of falls increases with age and varies according to residential location. Falls are more common in residential aged care facilities where 30-60% cases of falls were reported in 12 months than in hospitals with 17 falls out of 1000 bed days (Nay, 2009, p. 190). In Australia, for the year 2005-2006, the estimated number of hospitalized injury cases due to falls in people aged 65 years and over was 66, 800 – a rise of 10% since 2003-2004. Half of all fall injury cases for people aged 65 years and older oc cur from home (Byrne, 2010, p. 141). Falls are a major cause of morbidity and mortality among older people. In community-dwelling older people, 5-10% of falls result in major injuries such as fractures, head trauma, and major lacerations. In residential aged care facilities, major injuries range from 10-30%. Falls have also been identified as a contributory risk factor in 40% of residential aged care admissions (Nay, 2009, p. 192). Implications for Practice The increase in the incidence of falls among acute care facilities and residential aged care facilities seems to be alarming. High incidence of falls among older people implies that an enormous amount of effort must be put in prevention interventions and programs for falls. A review to assess the effectiveness of current prevention

Celia Cruz Essay Example | Topics and Well Written Essays - 1750 words

Celia Cruz - Essay Example She was a Cuban singer who came from a humble background until she rose to fame in the US. It is through her music that she encouraged the conservation of marginalized people, as well as, promoting a world Latin American identity, principally utilizing the different syncretic threads of Salsa, originated from Cuban. By doing so, she was able to make a huge contribution to the Cuban music. By doing so she made Salsa a highly historical genre, by using her influence of musical aspects from different countries. Salas is defined by ethnomusicologists, as a genre that has Cuban traditions, mixed with guaracha in addition to rumba (Abreu 96-100). Moreover, salsa also has a huge influence of Colombian cumbias, and merengues from the Dominican Republic in addition to Puerto Rican bombas, (Abreu 105-107). However, the final form of this genre was developed by Latin musicians in the US by combining all the named contributions with aspects of American rock and jazz (Brill 2011). Nevertheless, S alsa contains some African melodious elements, apparent in the principal percussive instrumentation especially the drums, as well as, the call and response approach which is used to improve the vocal layers. Additionally, there is a Spanish influence that can be identified in some instrumentation of the genre. In general, salsa’s structure is in a pattern of the main body piece followed by the call-and-response aspects (Brill 120-126). This is what offers Salas a rhythm which is fast and lively which is valued in its performance. This can be depicted in some of the famous Cuban music. For instance, â€Å"Flor de Mayo,† starts with the clear guitar timbre. Chord strumming is fast in tempo, with slight tension between notes. The melody’s structure is followed by guitar notes that can only best described to have a Spanish style. These are some of the aspects that are identified in Salsa music that are in Cruz songs. Therefore, one can say that her songs contributed a lot in the invention of Salsa music and mostly because she made it acceptable to different people of diverse origins and culture. This does not mean that the genre was accepted by all genertons. In the 1960s, the trending music was the American rock and pop and many Lation youths did not accept the Salsa rhythm as expected. The genre was associated with the old generation and termed as outdated. This is attributed to the fact that many of them wanted to assimilate into the prevailing American culture. However, decade later, there was an overwhelming popularity of Salsa with the emergence of Celia Cruz as the most popular artist and she was ready to satisfy the transformed enthusiasm portrayed by the Latin American music. Cruz was born in Barrio Santos Suarez in Havana, which was a black neighborhood of Cuba in in October 21, 1924 (Ortiz 5-7). She had 13 siblings but she is the only ones that showed interest in singing. This is because as a child, one or her key chores was singing to her younger siblings to sleep. This encouraged her to sing as a child and in her first appearance, she was able to earn a pair of shoes given to her by some tourist that were watching. She developed to a teenager and performed in numerous talent shows in the community and also at school. Her aunt took her to cabarets and nightclubs. She was supported by her family but the

Prescriptive and emergent approaches for developing strategies

Prescriptive and emergent approaches for developing strategies Introduction The concept of corporate strategy battles with the perennial issue of determining the overall purpose and scope of an organisation. From a contemporary perspective, it involves the specification of long-term goals and objectives that will add value to the business and cope with the uncertainty of modern times. As a practice, it consists of adopting courses of action and allocating resources in ways necessary for carrying out the overall objectives. Widely recognised as the most principal theories for strategy development, the prescriptive and emergent approaches must be examined within the context of an increasingly dynamic, highly competitive and global business environment. Powerful external forces are driving organisations to reduce costs, enhance processes and identify new opportunities for growth. Many businesses are compelled to make dramatic improvements not only to compete and prosper but also merely to survive. This brings to the fore the importance of determining how effectively the prescriptive and emergent approaches can meet the needs of todays businesses when formulating strategy. The Prescriptive Approach The prescriptive approach regards strategy development as a systematised and deterministic process where analysis of the organisation, its performance and external environment leads to the formation of a rational, long-term plan. Senior management is in charge of defining the final objectives and the plan is then put into action through the successive layers of the organisation. Techniques which feed this process include Porters heavily structured Five Forces model for analysing industry and Value Chain Analysis which highlights existing capabilities as a solid basis for competitive advantage. It is pointed out by Ansoff that firms in fast-paced, competitive environments who use a systematic process for strategic planning very often go on to dominate their marketplace. Their logical, analytical approach allows them to devise predictive and pre-emptive strategies from which they can meet new opportunities head on. For instance, in 1995 EasyJet used incredible foresight to introduce low cost flights allowing it to take advantage of a more cost-conscious European Market. Whats more, this approach makes it possible to organise complex activities and exercise a greater degree of control over different business units. For example, Tescos planning process resulted in well defined long-term goals and clear boundaries for its UK core business, retail service, non-food and international sectors. It has succeeded in achieving consistent growth and profit in all of these areas over recent years. Strategy formation which places a lot of weight on existing capability strengths is thought to be a secure basis on which a firm should define itself and optimise its position, particularly in times of rapid and turbulent change. For example, Motorola has successfully met the needs of emerging markets by using its fundamental technological strengths in electronic components to progress from supplying TVs and car radios to offering telecommunications services. From a contrary perspective,ÂÂ  Johnson states that the prescriptive model contains many assumptions that are unsustainable in todays business world. The logical approach implies that strategy development is always deliberate and that strategies are realised according to plan. However, empirical research by Mintzberg discounts this, highlighting that realised strategy tends to be only 10 to 30 percent of the intended strategy. This is mainly because unpredictable events, such as the introduction of new regulations or technologies, will regularly act to force the original strategy off its course. Additionally, the prescriptive approach to planning falls short in allowing for any learned elements to be absorbed into the strategy and so can limit an organisations ability to respond flexibly in todays rapidly changing environment. The narrow-minded manner in which it focuses on established areas of business and capabilities can hinder serious transformational change where reinvention is required. A further criticism is that the prescriptive model fails to complement modern organisational cultures where employees at lower levels are included in the decision making process. This type of involvement is frequently found in small or medium sized businesses. As a result, organisational creativity can be stifled and employee dissonance may occur as it is at these levels that work processes are most fully understood. The Emergent Approach Mintzberg put the idea forward that strategies can be unplanned, developing incrementally over time as a businesses actions adapt to a changing reality. Instead of meeting a premeditated plan, he argued that strategy evolves through a process of learning, adjustment and experimentation. Formulation of strategy runs parallel to implementation and managers at multiple organisational levels have a key input into the actual strategies pursued by the organisation. This models emphasis on learning underlies more recent theories which focus on the value of knowledge as a core organisational competence for gaining competitive advantage. An emergent approach leads to more creative and responsive strategy making which is well suited to the hyper-competitive and unpredictable environments of today. Interestingly, Hamel and Prahalad pointed out that the most successful firms in the world such as Microsoft and Apple Macintosh do not tie themselves down to mission, goals and objectives or the predetermined plan. In contrast with the prescriptive approach which focuses on creating a fit between established strengths and emerging opportunities, the emergent approach challenges the status quo by intentionally creating a misfit between these factors. Hence, it is more suited to instigating positive, transformational organisational change such as diversification or restructuring. It also has the added benefit of helping to reduce resistance to change as it allows time to build employee support while the strategy is taking shape. On a negative note, when formulation and implementation occur simultaneously there is a risk that strategy development becomes too slow and jumbled a process. This means that valuable opportunities may be missed along the way. Also, conflicting objectives from different groups can hinder strategy development, particularly when there are power shifts taking place during a major strategic change such as a merger. Without strict analysis and identifiable targets, objectives can lack clarity and there may be no real basis for evaluating performance. Indeed, it was pointed out by Brews and Hunt that an over-reliance on emergent strategy formation could result in underperformance. Conclusion Within the framework of an environment which is by and large unpredictable, many organisations are forced to become more flexible and adaptive to change. This supports the adoption of an emergent approach to strategy development which invokes a more intelligent capacity to respond to new opportunities. Nonetheless, such a strategy can preclude control over actions and may risk a lack of direction. A greater use of strategic planning tools for internal and external analysis would certainly facilitate improved organisational learning and enhance strategic thinking even while following an emergent approach. This recognition that the prescriptive and emergent processes, rather than being mutually exclusive, can be complementary approaches that reinforce each other is being highlighted in more recent theories such as the Logical Incrementalism approach proposed by Quinn. All in all, most viable strategies in todays business world should have customised elements of prescriptive and emergent characteristics in order to manage the complexities of their business and still triumph over changing circumstances.

Analysis of Marks and Spencer :: Retail Company England Marketing Essays

This is a report on Marks and Spencer a well known retail company in the UK. Marks and Spencer has also recently been in the news for falling profit and sales in 1999/2000. So Marks and Spencer is now on its way to recovery. It’s famous for setting the highest of standards in the retail industry, pioneering its own charge card and generating such snob value on its products, yet controlling prices to bring their products within most people's reach. Marks and Spencer has extended its brand overseas where it continues to achieve substantial growth. This is likely to be its main source of growth in the near and long term future as the company develops its franchise business. There are around 628 locations for Marks and Spencer’s. The company makes great weight of how it is run - first class customer service, operating efficiency (through economies of scale), long-term partnership with suppliers, financial services, staff rewards and overall packages the best in the high street. Following a wide-ranging and detailed strategic review of its business, the Board of Marks & Spencer has announced significant changes to the Group strategy and structure. The Board and management team is committed to restoring profitable growth. This will be achieved by total focus on the recovery of the UK Retail business. The organisation has always monitored its performance by first making clear objectives for the business. Without clear objectives it is difficult to evaluate what a marketing plan is trying to achieve or whether the plan has been successful. It is usual to translate marketing objectives into quantifiable â€Å"result areas†, such as market share, market penetration or growth of sales. Some of these may be further broken down into specific sales volumes, value goals or geographical targets. Marketing objectives allow Marks and Spencer to have a basis for evaluation which can then be analysed after a certain period of time. Each department most make sure that the organisational activities are co-ordinated in such a way that marketing objectives are met. Every organisation including Marks and Spencer involved in a marketing activity is faced with a number of constraints which seem to hinder their performances when monitored. Internal constraints relate to the resources available for Marks and Spencer, while External constraints involve a series of factors within the business environment that limit in one way or another, the organisation’s activities. Examples are below: Ø Consumers Ø Competitors Ø Economy Ø The law Marks and Spencer seem to monitor their performance by being market focused as they research all these constraints fully and will try to find solutions that enable it to turn weaknesses into their strengths threats into opportunities.

Five Steps to a Five: AP English Language Essay

The three types of essays mentioned in â€Å"Five Steps to a Five: AP English Language† are analysis, argumentative, and synthesis. An analysis essay is complied of different parts, it explains how the many parts can come together to produce a complete result. To have an argumentative essay you must acknowledge what you are defending and have sufficient and accurate information to support your claim. A synthesis essay should contain the main points of compared and contrast, cause and effect, and analysis of the writer’s topic. An analysis essay must analyze the author’s point of view, rhetorical devices used to achieve his or her purpose, stylistic elements, tone, real or imagined experience, and a discussion. To ensure that these points are made, simple tasks are recommended; for example spending one to three minutes reading and working the prompt, five minutes reading and making marginal notes regarding the passage, ten minutes preparing to write, twenty minutes writing the essay, and three minutes proofreading. To write an argumentative essay you must understand the nature of the position taken in the prompt, taking a specific stand with the assertion, and clearly and logically supporting the writer’s claim. When given an excerpt or statement you must understand what the passage is stating, then ask yourself if you agree or disagree. When you have successfully decided, the next step is to find information to support your opinion. Helpful tasks that can be taken to ensure that your essay is a success are to spend one to three minutes reading and working on the prompt, three minutes deciding on a position, ten to twelve minutes writing your essay, and three minutes proofreading. To have a presentable synthesis essay the writer must be able to read critically, understand the text, analyze the texts, develop a position on a given topic and support the position it, incorporate outside sources into texts of the essay, and always cite sources used in the essay. Before writing the author must read all prompts, deconstruct the synthesis, read and annotate each of the given texts, and decide how you will address the synthesis prompt. The tasks recommended for a excellent essay is to spend five to six minutes going back to the texts and deciding which you will use in your essay, eight to ten minutes planning the support of your position, twenty minutes writing the essay, three to four minutes checking to make certain that you have included the minimum number of sources and correctly cited them all, and three minutes proofreading. Analysis, argumentative, and synthesis are all excellent forms of essays in which you can state your opinion and support it in different ways. Analysis will allow the writer to read through and discover the main points that is needed, argumentative is a more aggressive statement in which the writer may defend his or her position. Whereas the synthesis essay is a way for the writer to compare and contrast different positions.

Legal Concepts in Healthcare

Legal Concepts in Healthcare The field of medicine is very sensitive since it involves dealing with human beings. Precautionary measures should be taken so as not to violate the fundamental rights of individuals/clients. Some actions in the course of interaction between the medical professionals and their clients may be so gross as to call for stern reaction in order to redress them.Advertising We will write a custom essay sample on Legal Concepts in Healthcare specifically for you for only $16.05 $11/page Learn More There are some instances where the clients have been mistreated by physicians and just like any other criminal case, legal actions are pursued (Sharpe, 2005). The essay discusses two common legal concepts; gross negligence, negligence, and malpractice and unintentional versus intentional torts and how they may apply in a health care setting. Gross negligence as used in legal terms refers to a misconduct exhibited as a result of being obviously reckless or careless that even an ordinary person with no legal background can tell (Westrick Dempski, 2008). It is an incident that may be termed an act of ignorance. Usually, ignorance is no defense in any court of law. Simple negligence, on the other hand, is a form of negligence that is exhibited by an individual but some degree of care seems to have been exercised by the defendant (Sharpe, 2005). Malpractice is closely related with negligence and refers to a practice that contravenes what is expected of a given individual, usually a professional or specialist like in the case of the medical field (Sharpe, 2005). When applied to a health care setting, these concepts help in categorizing the various malpractices by the medical professionals. Gross negligence, for instance, refers to utter disregard of principles and careless conduct that is so reckless even an individual with no medical background or training can tell its gravity (Westrick Dempski, 2008). These acts are usually deliberate and with ill inten t. Some of the actions may include; willfully leaving a surgical instrument in a patient’s body cavity or a surgeon deliberately amputating a limb which is not affected or infected in any way (Sharpe, 2005). However, sometimes the medical professional may end up committing a serious act even after exercising some degree of care and had no intention of maltreating the client. This amounts to simple negligence although it may prove difficult to differentiate between the two. In general, medical professionals and specialists like surgeons, dentists, and opticians may be charged with different cases of malpractices. Malpractice refers to the careless misconduct or negligent/improper actions by a professional in the course of his duties.Advertising Looking for essay on health law? Let's see if we can help you! Get your first paper with 15% OFF Learn More Medical malpractice generally refers to various forms of omissions and commissions as a result of varyin g degrees of negligence on the side of a medical professional (Westrick Dempski, 2008). Some of the medical malpractices include exposing confidential/patients of these acts include unjustified imprisonment, battery, cross-land trespass, psychological torture, violation of confidentiality laws, fraud, operation without consent of the patient or next of keen, and assault. They also include all the ill acts that a specialist may commit outside the medical profession. References Hill, S. S. Howlett, H. A. (2005). Success in practical nursing (5th ed). Elsevier Health Sciences Sharpe, C. C. (2005). Medical malpractice: liability and risk management. Greenwood Publishing Group Springhouse Corporation (2004). Physician’s legal handbook (5th ed). Lippincott Williams WilkinsAdvertising We will write a custom essay sample on Legal Concepts in Healthcare specifically for you for only $16.05 $11/page Learn More Westrick, S. J. Dempski, K. (2008). Understand ing nursing law and ethics. Jones Bartlett Learning

The Collapse of Gupta India

The Collapse of Gupta India The Gupta Empire may have lasted only about 230 years, but it was characterized by a sophisticated culture with innovative advances in literature, arts, and sciences. Its influence continues to be felt in art, dance, mathematics, and many other fields today, not just in India but across Asia and around the world. Called Indias Golden Age by most scholars, the Gupta Empire was likely founded by a member of a lower Hindu caste called Sri Gupta. He came from the Vaishya or farmer caste and founded the new dynasty in reaction to abuses by previous princely rulers. The Gupta were ardent Vaishnavas, devotees of Vishnu and they ruled as traditional Hindu monarchs. Advances of the Golden Age of Classical India During this Golden Age, India was part of an international trade network which also included other great classical empires of the day, the Han Dynasty in China to the east and the Roman Empire to the west. The famed Chinese pilgrim to India, Fa Hsien (Faxien) noted that Gupta law was exceptionally generous; crimes were punished only with fines. The rulers sponsored advances in science, painting, textiles, architecture, and literature. Gupta artists created marvelous sculptures and paintings, perhaps including the Ajanta caves. The surviving architecture includes palaces and purpose-built temples for both Hindu and Buddhist religions, such as the Parvati Temple at Nachana Kuthara and the Dashavatara Temple at Deogarh in Madhya Pradesh. New forms of music and dance, some of which are still performed today, flourished under Gupta patronage. The emperors also founded free hospitals for their citizens, as well as monasteries and universities. The classical Sanskrit language reached its apogee during this period as well, with poets such as Kalidasa and Dandi. The ancient texts of the Mahabharata and Ramayana were converted into sacred texts and the Vau and Matsya Puranas were composed. Scientific and mathematical advances include the invention of the number zero, Aryabhatas astonishingly accurate calculation of pi as 3.1416, and his equally amazing calculation that the solar year is 365.358 days long. Establishing the Gupta Dynasty In about 320 CE, the chief of a small kingdom called Magadha in southeastern India set out to conquer the neighboring kingdoms of Prayaga and Saketa. He used a combination of military might and marriage alliances to expand his kingdom into an empire. His name was Chandragupta I and through his conquests he formed the Gupta Empire. Many scholars believe that Chandraguptas family was from the Vaishya caste, which was the third tier out of four in the traditional Hindu caste system. If so, this was a major departure from Hindu tradition, in which the Brahmin priestly caste and the Kshatriya warrior/princely class generally held religious and secular power over the lower castes. In any case, Chandragupta rose from relative obscurity to reunite much of the Indian subcontinent, which had fragmented five centuries earlier after the fall of the Mauryan Empire in 185 BCE. Rulers of the Gupta Dynasty Chandraguptas son, Samudragupta (ruled 335–380 CE), was a brilliant warrior and statesman, sometimes called the Napoleon of India. Samudragupta, however, never faced a Waterloo, and was able to pass on a greatly expanded Gupta Empire to his sons. He extended the empire to the Deccan Plateau in the south, Punjab in the north, and Assam in the east. Samudragupta also was a talented poet and musician. His successor was Ramagupta, an ineffectual ruler, who was soon deposed and assassinated by his brother, Chandragupta II. Chandragupta II (r. 380–415 CE) expanded the empire still further, to its greatest extent. He conquered much of Gujarat in western India. Like his grandfather, Chandragupta II also used marriage alliances to expand the empire, marrying into control of Maharashtra and Madhya Pradesh, and adding the rich provinces of Punjab, Malwa, Rajputana, Saurashtra, and Gujarat. The city of Ujjain in Madhya Pradesh became a second capital for the Gupta Empire, which was based at Pataliputra in the north. Kumaragupta I succeeded his father in 415 and ruled for 40 years. His son, Skandagupta (r. 455–467 CE), is considered the last of the great Gupta rulers. During his reign, the Gupta Empire first faced incursions by the Huns, who would eventually bring down the empire. After him, lesser emperors, including Narasimha Gupta, Kumaragupta II, Buddhagupta, and Vishnugupta, ruled over the decline of the Gupta Empire. Although the late Gupta ruler Narasimhagupta managed to drive the Huns out of northern India in 528 CE, the effort and expense doomed the dynasty. The last recognized emperor of the Gupta Empire was Vishnugupta, who ruled from about 540 until the empire collapsed around 550 CE. Decline and Fall of the Gupta Empire As with the collapses of other classical political systems, the Gupta Empire crumbled under both internal and external pressures. Internally, the Gupta Dynasty grew weak from a number of succession disputes. As the emperors lost power, regional lords gained increasing autonomy. In a sprawling empire with weak leadership, it was easy for rebellions in Gujarat or Bengal to break out, and difficult for the Gupta emperors to put such uprisings down. By 500 CE, many regional princes were declaring their independence and refusing to pay taxes to the central Gupta state. These included the Maukhari Dynasty, who ruled over Uttar Pradesh and Magadha. By the later Gupta era, the government was having trouble collecting enough taxes to fund both its hugely complex bureaucracy and constant wars against foreign invaders like the Pushyamitras and the Huns. In part, this was due to the common peoples dislike of the meddlesome and unwieldy bureaucracy. Even those who felt a personal loyalty to the Gupta Emperor generally disliked his government and were happy to avoid paying for it if they could. Another factor, of course, was the near-constant rebellions among different provinces of the empire. Invasions In addition to internal disputes, the Gupta Empire faced constant threats of invasion from the north. The cost of fighting off these invasions drained the Gupta treasury, and the government had difficulty refilling the coffers. Among the most troublesome of the invaders were the White Huns (or Hunas), who conquered much of the northwestern section of Gupta territory by 500 CE. The Huns initial raids into India were led by a man who is called Toramana or Toraraya in Gupta records; these documents show that his troops began to pick off feudatory states from the Gupta domains around the year 500. In 510 CE, Toramana swooped down into central India and inflicted a decisive defeat at Eran on the Ganges river. The End of the Dynasty The records indicate that Toramanas reputation was strong enough that some princes voluntarily submitted to his rule. However, the records do not specify why the princes submitted: whether it was because he had a reputation as a great military strategist, was a blood-thirsty tyrant, was a better ruler than the Gupta alternatives, or something else. Eventually, this branch of the Huns adopted Hinduism and was assimilated into Indian society. Although none of the invading groups managed to completely overrun the Gupta Empire, the financial hardship of the battles helped hasten the end of the dynasty. Almost unbelievably, the Huns, or their direct ancestors the Xiongnu, had the same effect on two of the other great classical civilizations in earlier centuries: Han China, which collapsed in 221 CE and the Roman Empire, which fell in 476 CE. Sources Agrawal, Ashvini. Rise and Fall of the Imperial Guptas. Motilal Banarsidass Publishers, 1989. Chaurasia, Radhey Sham. History of Ancient India. Atlantic Publishers, 2002.Dwivedi, Gautam N. The Western Limits of the Gupta Empire. Proceedings of the Indian History Congress 34, 1973, pp. 76-79.Goyal, Shankar. Historiography of the Imperial Guptas: Old and New. Annals of the Bhandarkar Oriental Research Institute 77.1/4, 1996, pp. 1–33.Mookerji, Radhakumud. The Gupta Empire. Motilal Banarsidass Publishers, 1989.Prakash, Budha. Last Days of the Gupta Empire. Annals of the Bhandarkar Oriental Research Institute 27.1/2, 1946, pp. 124-41. Vajpeyi, Raghavendra. A Critique of the Huna Invasion Theory. Proceedings of the Indian History Congress 39, 1978, pp. 62-66.

The Logistics of Product Recovery (EndofLife) Case Study

The Logistics of Product Recovery (EndofLife) - Case Study Example It is now being realized that producer responsibility needs to be increased in areas of Northern America and to increasingly shift the burden of environmental protection for the government to the producers. This also enables the government to shift the responsibility of economic responsibility from the government to the local taxpayers. The scope for such laws is also being expanded to other non-recyclable wastes such as fluorescent bulbs, paint, mattresses, appliances, mercury thermostats and medical sharps. The use of EPR shall essentially require the formation of a separate and somewhat parallel system of waste management or collection mechanism that is the key to increase the quantity of waste collected. The maximization achieved within the collection system is also responsible for increased industrial as well as consumer participation in management of waste products. The laws help in mandating such convenience in collection methods which is difficult to define (Michelini & Razzoli, 2010). This paper is aimed at analyzing the scope of reverse logistic management and developing of a proper model that would be helpful in EPR management deriving most benefits from reuse and recycle of end-of-life products. The paper suggests the establishment of the OEM takeback methodology for the benefit of companies and the environment because it is the most efficient management technique for wastes. However, it also suggests the use of pooled takeback within the collection mechanism to facilitate convenience and also eliminate the drawbacks of the OEM method by way of using the benefits of pooled takeback in the collection procedure. The components, product, equipment, materials and even the total technical system can go backwards in the supply chain for rework in the manufacturing process so as to facilitate reuse and enhancement of unsatisfactory products on quality and component

The assignment is to choose between problem 2 and 3 of the Problem Essay

The assignment is to choose between problem 2 and 3 of the Problem Solving Activities (pages 428 and 429) and prepare a word report of your findings - Essay Example If a student or the person applying has this information at hand then this stage will not be a problem to pass. I also found out that you can actually log into the website using your social media account which is very good considering the fact that almost every student have one or more social accounts. They especially use the Facebook accounts for verification and thus one doesn’t have to go through the rigorous process of filling in information because all will be obtained from the website itself. After feeding all the information correctly you will receive notification in your email account and thus you will use it to activate your account with my majors and access the services. On the website you will find several courses that you can major on after your undergraduate level and thus you get assisted on the way forward on how to select a course online. The website is easy to use and is helpful to all the students who would like to identify the areas of studies they would like t0o major on. It is essential to visit this site if you have an ambition to strengthen your studies by advancing it via majoring in specific fields. The website generally assist students achieve their