Electronic Channels Assignment Example | Topics and Well Written Essays - 250 words

Electronic Channels - Assignment Example Most often this comes as a contrary expectation to any commercial entity. Since the electronic channels allow the consumers to carry out their transactions from most convenient locations, they eventually affect the role of retailing traders. Even when the electronic retailing mode is scaled against other methods, it contributes to a very minor percentage of the total retailing outputs. This however is bound to change with the advent of ever changing scale of globalization. It is expected to shoot higher in the near future when electronic means shall be inevitable to institutions and corporations (Lechner & Hummel, 2002). Some products are more appropriate for electronic channels. This is largely determined by the market trends and behavior. For instance, some factors like public perception on the channel fundamentally contribute to this preference. Moreover, other factors like the effort inputted by the market segment, time that the commodity takes to be delivered and intentions by consumers to search for prices, all count (Lechner & Hummel, 2002). There are some products inappropriate for electronic channels. Examples of such include experience goods. These are goods that one has to assess based on their tastes and preference for them. For example, a brand of wine can only be assessed once one has had a taste, but not by online inquiry (Lechner & Hummel, 2002). Lechner, U. & Hummel, J. (2002). Business models and system architectures of virtual communities: from a sociological phenomenon to peer-to-peer architectures. International Journal of Electronic Commerce , 41-53. Soon, A. & Luis, F. (2012). Social Media in Governmnent- Selections from the 12th Annual International Conference on Digital Government Research(dg2011). Journal of Information Technology Management, Policies, and Practices ,

Argue that porn has changed sexuality today Research Paper

Argue that porn has changed sexuality today - Research Paper Example Studies concerning the impacts of pornography in the society focus on various outcomes including potential influences on sexual dysfunction, rape, and difficulties with sexual relationships among others. Individuals can easily access sexually explicit materials from the internet and the effect or influence of this is questionable. Today, exposure to pornography has left many sexually active and independent young women to engage in some sexual acts and do things that they do not want to do in bed which they later regret. According to many studies concerning this same topic, men were found to use sexually explicit materials from the internet as opposed to women. Indeed, watching pornography greatly affect individuals’ sexual behaviours which in turn influences their relationships negatively. Following an extensive research, this paper focuses on the relationship between pornography and sexual aggressiveness among individuals. Even though exposure to pornography has been associat ed with sexual violence and failing relationships, its contribution to sexual enhancement for some people should not be ignored. Individuals exposed to extreme pornographic images are more likely to become addicted or tolerant to such films and this in turn will affect their sexual response. Despite the presence of many studies conducted on this issue, there is still no clear evidence confirming that virtual pornographic images and films can make individuals become addicted to such acts. This is because addiction to porn sex or images influences individuals’ sexual experience in general making them to be sexually dysfunctional since the real sexual experiences do not arouse these addicts. In addition, most people using pornographic materials tend to fantasize about or imitate some of the scenes they have watched in these films in order to get aroused during sexual intercourse with their partners. Pornography is one common way through which

Healing in Medicine: Norman Bethune

Healing in Medicine: Norman Bethune The True Spirit of Healing in Medicine: Norman Bethune Introduction Henry Norman Bethune was a Canadian doctor who became famous for his selfless service of people in the Second Sino-Japanese War. His service endeared him to Mao Zedong, who hailed him as a communist and supporter of the Chinese people’s efforts for liberation. Even today, Bethune’s popularity in China stands undisputed with his statues present all over the country. There is no doubt that Bethune had in him the true spirit of healing, a unique spirit, because doctors often perceive their professions as scientific pursuits or even money making endeavors. This is illustrated in the manner in which pharmaceutical companies and doctors work hand in hand to achieve profits and market prominence by selling medicines. Bethune’s dedication to his profession was illustrated in the manner in which he served in the World War I and the Spanish Civil War before his stint in the Sino-Japanese War, in spite of his open contention that wars were meant to make profits (Shepherd an d Là ©vesque 147). He was known repeatedly state that â€Å"the private economic profit† (Clarkson 40; Stewart and Stewart 317; Wilson 75) should have no place in medicine. In addition, he was also a proficient inventor, who designed and altered several surgical instruments, such as the portable blood transfusion system he developed in the Spanish Civil War (Stewart and Stewart 92, 95). Moreover, many of his inventions continue to be in use today (Stewart and Stewart 92, 95). It is also notable that while Bethune passionately and dedicatedly adhered to his professional ideals, he also had clear political ideologies. In the Spanish Civil War, he sided with the democratic republic and during the Second Sino-Japanese War, he sided with the rural population in China and accepted communism as opposed to Imperialism. However, today he is heralded in China for his communist ethoses, which were very different from the communism that was practiced in China under Mao Zedong. This pape r contends that Bethune was not simply a doctor by profession but also a healer at heart who formed political ideals according to the welfare of humanity, and thus, his image as a communist leader in and outside China might be somewhat misconstrued. Discussion Bethune’s ideology behind traveling all the way to China in 1938 and to serve the people in the Sino-Japanese War was to aid the suffering and poor people there. This was in line with his endeavors in his life thus far, that is, in World War I and the Spanish Civil War. He also carried out crisis surgical procedures on the casualties in the war as well as instituted training for medical personnel for the same (Stewart and Stewart 32). He also refused to treat the casualties by considering their race, culture, political side, or even the side in the war (Stewart and Stewart 32). Clearly, he was dedicated to the cause of serving his patients, irrespective of the social conditions. As a doctor, he treated the people who were suffering and sick. He was also believed in the communist ideologies, that is, those that had been propounded by Marx and was a member of the Canadian Communist Party (Stewart and Stewart 124). This was in spite of the fact that in those days, it was illegal to be a part of the communist party in Canada (Stewart and Stewart 124). However, this was naturally because of the conflicts between what would become the allied and axis powers in the World War II. In fact, most people in Canada associated communism with Stalinist and Nazi policies of control (Stewart and Stewart 371). Moreover, the United States’ staunch anti-communist policies must have also influenced the Canadian policies. However, in Bethune’s philosophy, the poor, proletariats, who were subjugated under capitalism or were the casualties in war, should be side he supports. Consequently, he became a part of the communist party in Canada, because he believed in Marxist philosophies, which communists promised to practice. Clearly, his political ideology was founded in his dedication to his professional and moral ideal of serving the suffering and the weak. When Mao Zedong welcomed Bethune as a communist comrade, he was impressed with Bethune’s dedication to the communist ideals. Bethune illustrated his ideals with his dedication to his profession and by serving in the frontlines in the war. As mentioned before, this was not different from the manner in which he served in World War I and the Spanish Civil War. However, Mao interpreted Bethune’s work and ideologies as his dedication to the communist cause and the cause of the people. It must be remembered that under Mao’s rule, there was no growth of the proletariats and the Chinese economy collapsed as all the contributing members to the economy, such as, doctors, owners of industries, and lawyers were banished from their jobs to serve in the rural areas. In such conditions, the overall suffering, illness, and pain experienced by the Chinese people were probably worse if not as bad as in Imperial China. Although Bethune died in China of blood poisoning, while servin g in the Second Sino-Japanese War, he was, nevertheless, unaware of the true ethos of the brand of communism that would be practiced by Mao. Considering his ideals, he would have probably never wanted to be a part of this kind of communism. Ultimately, Bethune was a man who wanted to serve the people and not simply have a political ideal, where personal and profit goals were in focus. Today, it can be said that communism and democracy have both failed in the ability to separate the profit making processes from the social serving ones. Given these facts, Bethune would have probably sought to be a part of a more humanitarian political ideology. Notably, Bethune’s legacy rests on the fact that Mao published an essay on him—In the Memory of Norman Bethune in 1939—for unselfishly serving in the Second Sino-Japanese War. This essay was considered essential reading in Chinese schools then and even today, students are required to be familiar with this essay. Indeed, the philosophy of the essay is in tune with Bethune’s philosophies. Consider the following excerpt from the essay: We Chinese Communists must also follow this line in our practice. We must unite with the proletariat of all the capitalist countries, with the proletariat of Japan, Britain, the United States, Germany, Italy and all other capitalist countries, for this is the only way to overthrow imperialism, to liberate our nation and people and to liberate the other nations and peoples of the world (Tse-tung) Clearly, Bethune would have been glad to be associated with such ideologies. He expressed his views on his profession by stating that, â€Å"medicine, as we are practising it, is a luxury trade† (Allan and Gordon 130). He further abhorred the use of monetary ends in practicing medicine and believed individualism, which is always associated with democracy and never with communism, as the reason for such a state of affairs (Allan and Gordon 130). However, Bethune died well before the Chinese Cultural Revolution of the 1960s started. This was a time when millions of Chinese died because communism had turned to totalitarianism (Yan and Gao 2). The death toll in the Chinese Cultural Revolution has not been released by the Chinese government until date (Yan and Gao 2). However, this was a time when people were ruthlessly massacred by governmental encouragement of mobs and by authorized attacks on civilian populations by military personnel (Yan and Gao 2). Moreover, the anti-democrac y stand Bethune held would have probably been shaken if he had lived to experience the shock the world felt when the truth that Hitler carried out genocides in Germany was publicly known and acknowledged after World War II. However, since he never lived to experience such events, and thoroughly believed communism to be anti-exploitation, he stood by it while practicing his medical ideologies. It can also be recalled that Bethune was virtually unknown in Canada well after he died. Canadians and the rest of the Western world did not know about him until 1952, when Ted Allan and Sydney Gordon published their book, The Scalpel, the Sword: The Story of Doctor Norman Bethune (a new version is mentioned in the works cited section of this paper). However, unfortunately, they hailed him as a communist hero in this book. However, the timing could not have been worse, because in this Cold War era, anti-communist feelings thrived in Canada (Stewart and Stewart 327). Thus, Bethune’s contributions to science and his altruism were well forgotten until much later. Only in the past few decades, especially since China has cautiously opened its doors to the western world for trade has Bethune’s abilities and work been acknowledged. Today it is known that Bethune was among the original advocates of socialized medicine, which is in high demand in Canada and in the rest of wester n world—the Obamacare policies next door are perhaps the best examples of this. Bethune also formed the Montreal Group for the Security of People’s Health (Stewart and Stewart 371), which established the need for socialized medicine. Bethune has also visited the Soviet Union to understand and learn about socialized medicine (Stewart and Stewart 122). Such endeavors eased his way into the political ideology that was communism and thus, he became a part of the Communist Party of Canada. In the most unbeknownst manner, he became a part of a political thought that defied the altruism fundamental to his ideologies. Conclusion This paper illustrated the manner in which Bethune contributed toward the development of medicine and struggled to treat the injured and the sick as a doctor. Undeniably, he endeavoured to achieve his professional idealism through his research and treatment as in shown by his inventions. Similarly, as became aware of the social and economic characteristics of disease, he adopted a political thought that he believed cared for the proletariats and the suffering as he did. However, he was not well informed about the nature of such communism or even to of democracy. As time showed, both were capable of exploitation, and in fact, communism enabled totalitarianism—a concept that Bethune would have definitely abhorred considering his ideologies. It can be thus concluded from the facts presented in this paper that Bethune was indeed a dedicated doctor, who truly adhered by the Hippocratic Oath as well as formed political ideals keeping the welfare of humanity in mind. However, his ima ge as a communist leader in and outside China has been misconstrued over the years, since he died well before the harms of communism were experienced by the world. Work Cited Allan, Ted and Sydney Gordon. The Story of Doctor Norman Bethune. Dundurn Press: Dundurn. 2009. Print. Clarkson, Adrienne. Extraordinary Canadians: Norman Bethune. Toronto: Penguin Canada. 2009. Print. Stewart, Roderick and Stewart, Sharon. Phoenix: The Life of Norman Bethune. Toronto: McGill-Queen’s Press . Shephard, David A. E, and AndreÃÅ' e LeÃÅ' vesque. Norman Bethune: His Times and His Legacy. Ottawa, Ontario: Published by the Canadian Public Health Association, 1982. Print. Tse-tung, Mao. In Memory of Norman Bethune. 1939. Web. Accessed on April 15, 2015 from https://www.marxists.org/reference/archive/mao/selected-works/volume-2/mswv2_25.htm. Wilson, John. Norman Bethune. Dundurn: Dundurn Press. 1999. Print. Yan, Jiaqi, and Gao Gao. Turbulent Decade: A History of the Cultural Revolution. Honolulu: Univ. of Hawaii Press, 1996. Print.

Freedom comes from within yourself :: essays research papers

Freedom in the Hindu Culture   Ã‚  Ã‚  Ã‚  Ã‚  Over the past three years in America we have been bombarded with the word freedom as a call to action or a word to persuade us to follow a specific view. Although our society was born on freedom as an idea, its meaning has been used in many ways. Hinduism is also a religion and a culture that places a lot of meaning on freedom but they give a different meaning to it. From learning about Hindu culture in this class their focus on it follows suit as does our version. While our â€Å"freedom† is an idea that can be used in many different ways the Hindu â€Å"Freedom† is a more pure idea as it seems the rest of the culture is. In the Eastern culture freedom comes along with a level or state that you have reached in your life. To understand the meaning of freedom you also have to understand its relation to words like Samsara, Avidya, Maya and Moksha. These are all part of the journey towards the Hindu concept of freedom. Samsara is important in defining freedom in Hindu terms because it is what you want freedom from. Samsara is the continuous cycle of life that takes place in the material world. It is thought of as a negative because it keeps us from moving on and up spiritually. Maya is a concept in Hinduism that relates to man disillusioning himself. The idea is that there is no such thing as an individual existence. When a person is trying to better their standing or wealth they are disillusioning themselves. In the Eastern culture you do not work harder to better yourself you work harder to better the world as a whole through your actions in life. This brings you closer to unity with the â€Å"Divine.† Avidya is similar to Maya. It is when the man is disillusioning himself that Avidya describes. When he denies his true â€Å"Self â€Å" and moves farther away from knowledge he is not taking care of his soul. Avidya is a product of the soul as well as a part of the soul. A person can always move away from this and make his soul healthy again by seeking truth and trying to reach the higher levels of spirituality. In the final stage of life we see Moksha come into play. After freeing yourself from material ties in the third stage of life you move on to the fourth and last. Freedom comes from within yourself :: essays research papers Freedom in the Hindu Culture   Ã‚  Ã‚  Ã‚  Ã‚  Over the past three years in America we have been bombarded with the word freedom as a call to action or a word to persuade us to follow a specific view. Although our society was born on freedom as an idea, its meaning has been used in many ways. Hinduism is also a religion and a culture that places a lot of meaning on freedom but they give a different meaning to it. From learning about Hindu culture in this class their focus on it follows suit as does our version. While our â€Å"freedom† is an idea that can be used in many different ways the Hindu â€Å"Freedom† is a more pure idea as it seems the rest of the culture is. In the Eastern culture freedom comes along with a level or state that you have reached in your life. To understand the meaning of freedom you also have to understand its relation to words like Samsara, Avidya, Maya and Moksha. These are all part of the journey towards the Hindu concept of freedom. Samsara is important in defining freedom in Hindu terms because it is what you want freedom from. Samsara is the continuous cycle of life that takes place in the material world. It is thought of as a negative because it keeps us from moving on and up spiritually. Maya is a concept in Hinduism that relates to man disillusioning himself. The idea is that there is no such thing as an individual existence. When a person is trying to better their standing or wealth they are disillusioning themselves. In the Eastern culture you do not work harder to better yourself you work harder to better the world as a whole through your actions in life. This brings you closer to unity with the â€Å"Divine.† Avidya is similar to Maya. It is when the man is disillusioning himself that Avidya describes. When he denies his true â€Å"Self â€Å" and moves farther away from knowledge he is not taking care of his soul. Avidya is a product of the soul as well as a part of the soul. A person can always move away from this and make his soul healthy again by seeking truth and trying to reach the higher levels of spirituality. In the final stage of life we see Moksha come into play. After freeing yourself from material ties in the third stage of life you move on to the fourth and last.

The Nature of Viruses

Viruses are sub-cellular agents of infection that must utilize the cellular machinery of bacteria, plants or animals in order to reproduce. Composed of a single strand of genetic material (DNA or RNA) encased in a protein capsid, a virus is too small to be seen by standard light microscopy; indeed, most are less than one hundredth the size of a bacterium. Specific proteins on the viral capsid attach to receptors on the host cell; this attachment process is essential to viral infectivity and explains why viruses may only infect the cells of certain species or may only infect certain cells or tissues within a given host species. While the infecting virus triggers an immune response in the host, some are capable of suppressing that response by infecting and killing cells that control immunity (e. g. HIV attacks lymphocytes). In addition, while most infected cells are destroyed by viral replication, some viruses enter a latent phase within cells, reactivating in the future to produce chronic or relapsing infections. Many viruses use specific carriers (known as vectors) such as mosquitoes, ticks, bats and rodents that transmit the virus to a susceptible host while others are spread between individuals via blood contact or through respiratory, intestinal or sexual secretions. Of special concern is the fact that mutations within the viral genome may allow viruses to skip from one host (e. g. birds, swine, monkeys) to another (e. g. humans), unleashing pandemics. Many common human infections are produced by viruses; these include the common cold, influenza, mononucleosis, herpes infections (including shingles), viral hepatitis (A, B, C and others), HIV, viral gastroenteritis, conjunctivitis, viral pneumonia, encephalitis, viral meningitis and viral infections of the heart, including pericarditis and myocarditis. While viruses do not respond to antibiotics, specific antiviral agents may control (though not cure) chronic disease (such as HIV, Hepatitis B and Hepatitis C) or may modify the severity of acute infection (as in influenza and herpes infections). However, in most viral infections, treatment is, for now, purely symptomatic and supportive. On the other hand, vaccines are capable of preventing some viral infections (e. g. herpes simplex, measles, mumps, rubella, varicella, Hepatitis B) or reducing the severity of an acute infection (e. g. influenza). Beyond the acute or chronic illness that they produce, some viral infections (such and Hepatitis C and certain strains of herpes simplex) are known to be precursors of malignancy. Finally, many researchers suspect that viruses play a role in the pathogenesis of chronic illnesses such as multiple sclerosis and autoimmune disorders. ttp://naturesblog. blogspot. com/2013/01/the-nature-of-viruses. html The Nature of Viruses Viruses exist in two different states, the extracellular infectious particle or virion and the intracellular state consisting of viral nucleic acid. The capsid may be a polyhedron or a helix, or a combination of both (in some phages). Viruses are infective micro ¬o rganisms that show several differences from typical microbial cells. 1. Size. The size range of viruses is from about 20 to 300 nm. On the whole, viruses are much smaller than bacteria. Most animal viruses and all plant viruses and phages are invisible under the light microscope. 2. Simple structure. Viruses have very simple structures. The simplest viruses are nucleoprotein particles consisting of genetic material (DNA or RNA) surrounded by a protein capsid. In this respect they differ from typical cells which arc made up) of proteins, carbohydrates, lipids and nuc1eicacids. The more complex viruses contain lipids and carbohydrates in addition to proteins and nucleic acids, e. g. the enveloped viruses 3. Absence of cellular structure. Viruses do not have any cytoplasm, and thus cytoplasmic organelles like mitochondria, Golgi complexes, lysosomes, ribosomes, etc. , are absent. They do not have any limiting cell membrane. They utilize the ribosomes of the host cell for protein synthesis during reproduction. 4. No independent metabolism. Viruses cannot multiply outside a living cell. No virus has been cultivated in a cell-free medium. Viruses do not have an independent metabolism. They are metabo ¬lically inactive outside the host cell because they do not posses enzyme systems and protein synthesis machinery. Viral nucleic acid replicates by utilizing the protein synthesis machinery of the host. It codes for the synthesis of a limited number of viral proteins, including the subunits or capsomeres of the capsid, the tail protein and some enzymes concerned Viruses have only one nucleic acid, either DNA or RNA. Typical cells have both DNA and RNA. Genomes of certain with the synthesis or the release of virions. 5. Nucleic acids. RNA viruses can be transcribed into complementary DNA strands in the infected host cells, e. g. Rous Sarcoma Virus (RSV). Such RNA viruses are therefore also called RNA-DNA viruses. 6. Crystallization. Many of the smaller viruses can be crystallized, and thus behave like chemicals. 7. No growth and division. Viruses do not have the power of growth and division. A fully formed virus does not increase in, size by addition of new molecules. The virus itself cannot divide. Only its genetic material (RNA or DNA) is capable of reproduction and that too only in a host cell. It will thus be seen that viruses do not show all the characteris ¬tics of typical living organisms. They, however, possess two funda ¬mental characteristics of living systems. Firstly, they contain nucleic acid as their genetic material. The nucleic acid contains instructions for the structure and function of the virus. Secondly, they can reproduce themselves, even if only by using the host cells synthesis machinery. Viral genomes The nucleic acid comprising the genome may be single-stranded or double-stranded, & in a linear, circular or segmented configuration. Single-stranded virus genomes may be: †¢ positive (+)sense, i. e. of the same polarity (nucleotide sequence) as mRNA †¢ negative (-)sense Ambisense – a mixture of the two. N/B. Virus genomes range in size from approximately 3,200 nucleotides (nt) to approximately 1. 2 million base pairs Unlike the genomes of all cells, which are composed of DNA, virus genomes may contain their genetic information encoded in either DNA or RNA. Since viruses are obligate intracellular parasites only able to replicate inside the appropriate host cells, the genome must contain information encoded in a form which can be recognized & decoded by the particular type of cell parasitized. Thus, the genetic code employed by the virus must match or at least be recognized by the host organism. Similarly, the control signals which direct the expression of virus genes must be appropriate to the host. Many of the DNA viruses of eukaryotes closely resemble their host cells in terms of the biology of their genomes: Some DNA virus genomes are complexed with cellular histones to form a chromatin-like structure inside the virus particle. http://expertscolumn. com/content/nature-viruses http://www. mcb. uct. ac. za/tutorial/virorig. html Viral evolution Viral evolution is a subfield of evolutionary biology and virology that is specifically concerned with the evolution of viruses. Many viruses, in particular RNA viruses, have short generation times and relatively high mutation rates (on the order of one point mutation or more per genome per round of replication for RNA viruses). This elevated mutation rate, when combined with natural selection, allows viruses to quickly adapt to changes in their host environment. Viral evolution is an important aspect of the epidemiology of viral diseases such as influenza (influenza virus), AIDS (HIV), and hepatitis (e. . HCV). It also causes problems in the development of successful vaccines and antiviral drugs, as resistant mutations often appear within weeks or months after the beginning of the treatment. One of the main theoretical models to study viral evolution is the quasispecies model, as the viral quasispecies. | Origins Viruses are ancient. Studies at the molecular level have revealed relationships between viruses infecting organisms from each of the three domains of life, and viral proteins that pre-date the divergence of life and thus the last universal common ancestor. 1] This indicates that viruses emerged early in the evolution of life and existed before modern cells. [2] There are three classical hypotheses on the origins of viruses: Viruses may have once been small cells that parasitised larger cells (the degeneracy hypothesis[3][4] or reduction hypothesis[5]); some viruses may have evolved from bits of DNA or RNA that â€Å"escaped† from the genes of a larger organism (the vagrancy hypothesis[6] or escape hypothesis); or viruses could have evolved from complex molecules of protein and nucleic acid at the same time as cells first appeared on earth (the virus-first hypothesis). 5] None of these hypotheses was fully accepted: the regressive hypothesis did not explain why even the smallest of cellular parasites do not resemble viruses in any way. The escape hypothesis did not explain the complex capsids and other structures on virus particles. The virus-first hypothesis was quickly dismissed because it contravened the definition of viruses, in that they require host cells. [5] Virologists are, however, beginning to reconsider and re-evaluate all three hypotheses. [7][8] http://en. wikipedia. org/wiki/Viral_evolution Evolution Time-line of paleoviruses in the human lineage[9] Viruses do not form fossils in the traditional sense, because they are much smaller than the grains of sedimentary rocks that fossilize plants and animals. However, the genomes of many organism contain endogenous viral elements (EVEs). These DNA sequences are the remnants of ancient virus genes and genomes that ancestrally ‘invaded' the host germline. For example, the genomes of most vertebrate species contain hundreds to thousands of sequences derived from ancient retroviruses. These sequences are a valuable source of retrospective evidence about the evolutionary history of viruses, and have given birth to the science of paleovirology. 9] The evolutionary history of viruses can to some extent be inferred from analysis of contemporary viral genomes. The mutation rates for many viruses have been measured, and application of a molecular clock allows dates of divergence to be inferred. [10] Viruses evolve through changes in their DNA (or RNA), some quite rapidly, and the best adapted mutants quickly outnumber their less fit counterparts. In this sense their evolution is Darwinian, just like that of their host organisms. [11] The way viruses reproduce in their host cells makes them particularly susceptible to the genetic changes that help to drive their evolution. 12] The RNA viruses are especially prone to mutations. [13] In host cells there are mechanisms for correcting mistakes when DNA replicates and these kick in whenever cells divide. [13] These important mechanisms prevent potentially lethal mutations from being passed on to offspring. But these mechanisms do not work for RNA and when an RNA virus replicates in its host cell, changes in their genes are occasionally introduced in error, some of which are lethal. One virus part icle can produce millions of progeny viruses in just one cycle of replication, therefore the production of a few â€Å"dud† viruses is not a problem. Most mutations are â€Å"silent† and do not result in any obvious changes to the progeny viruses, but others confer advantages that increase the fitness of the viruses in the environment. These could be changes to the virus particles that disguise them so they are not identified by the cells of the immune system or changes that make antiviral drugs less effective. Both of these changes occur frequently with HIV. [14] Phylogenetic tree showing the relationships of morbilliviruses of different species[15] Many viruses (for example, influenza A virus) can â€Å"shuffle† their genes with other viruses when two similar strains infect the same cell. This phenomenon is called genetic shift, and is often the cause of new and more virulent strains appearing. Other viruses change more slowly as mutations in their genes gradually accumulate over time, a process known as genetic drift. [16] Through these mechanisms new viruses are constantly emerging and present a continuing challenge to attempts to control the diseases they cause. [17][18] Most species of viruses are now known to have common ancestors, and although the â€Å"virus first† hypothesis has yet to gain full acceptance, there is little doubt that the thousands of species of modern viruses have evolved from less numerous ancient ones. 19] The morbilliviruses, for example, are a group of closely related, but distinct viruses that infect a broad range of animals. The group includes measles virus, which infects humans and primates; canine distemper virus, which infects many animals including dogs, cats, bears, weasels and hyaenas; rinderpest, which infects cattle and buffalo; and other viruses of seals, porpoises and dolphins. 20] Although it not possible to prove which of these rapidly evolving viruses is the earliest, for such a closely related group of viruses to be found in such diverse hosts suggests a possible ancient common ancestor. [21] The Nature of Viruses Viruses are sub-cellular agents of infection that must utilize the cellular machinery of bacteria, plants or animals in order to reproduce. Composed of a single strand of genetic material (DNA or RNA) encased in a protein capsid, a virus is too small to be seen by standard light microscopy; indeed, most are less than one hundredth the size of a bacterium. Specific proteins on the viral capsid attach to receptors on the host cell; this attachment process is essential to viral infectivity and explains why viruses may only infect the cells of certain species or may only infect certain cells or tissues within a given host species. While the infecting virus triggers an immune response in the host, some are capable of suppressing that response by infecting and killing cells that control immunity (e. g. HIV attacks lymphocytes). In addition, while most infected cells are destroyed by viral replication, some viruses enter a latent phase within cells, reactivating in the future to produce chronic or relapsing infections. Many viruses use specific carriers (known as vectors) such as mosquitoes, ticks, bats and rodents that transmit the virus to a susceptible host while others are spread between individuals via blood contact or through respiratory, intestinal or sexual secretions. Of special concern is the fact that mutations within the viral genome may allow viruses to skip from one host (e. g. birds, swine, monkeys) to another (e. g. humans), unleashing pandemics. Many common human infections are produced by viruses; these include the common cold, influenza, mononucleosis, herpes infections (including shingles), viral hepatitis (A, B, C and others), HIV, viral gastroenteritis, conjunctivitis, viral pneumonia, encephalitis, viral meningitis and viral infections of the heart, including pericarditis and myocarditis. While viruses do not respond to antibiotics, specific antiviral agents may control (though not cure) chronic disease (such as HIV, Hepatitis B and Hepatitis C) or may modify the severity of acute infection (as in influenza and herpes infections). However, in most viral infections, treatment is, for now, purely symptomatic and supportive. On the other hand, vaccines are capable of preventing some viral infections (e. g. erpes simplex, measles, mumps, rubella, varicella, Hepatitis B) or reducing the severity of an acute infection (e. g. influenza). Beyond the acute or chronic illness that they produce, some viral infections (such and Hepatitis C and certain strains of herpes simplex) are known to be precursors of malignancy. Finally, many researchers suspect that viruses play a role in the pathogenesis of chronic illnesses such as multiple sclerosis and autoimmune disorders. development of viruses (images)

English coursework Essay

The creature not only has beautiful thoughts in this quotation but uses sensitive language: attracted, lovely, delight. However later on the creature explains that rage grasped hold of him as he realised that he would never enjoy her company. This explains that the creature is desperate to love someone, but because everyone treats him as if he is sub-human he is filled with fury, which is a natural human reaction. This is a reoccurring theme throughout the novel, and it becomes blatantly obvious that if humans treated him with respect and admiration, the creature would have never caused desolation. The above quote is far from the only example of this reoccurring theme in the novel. When the creature studies the cottagers we realise that love and desire are an element of his personality; ‘The more I saw of them, the greater became my desire to claim their protection and kindness; my heart yearned to be known and loved by these amiable creatures: to see their sweet looks directed towards me with affection was the utmost limit of my ambition. ‘ The creature clearly desperately craves for their admiration but when the cottagers encounter him, they scorn and beat him. It is clear that in this situation it is the cottagers who are the monster and the creature that is human, as the creature is reaching out for love and friendship, but the cottages dismiss him and beat him with malicious intent. At the time of the creation of this novel, a revolution was in progress in France. Throughout the novel there is an underlying connection between its story and the French revolution that became apparent. In France the radical reform was causing a severe amount of controversy and violence. Some believed the reform to be a positive movement as it would create a more democratic country, however there were others who believed that the reform would damage traditions and make several workers redundant. Therefore, despite the reformists’ intentions being good, the result caused violence and destruction. This theme is paralleled in the novel as Frankenstein intended to defeat death thus helping humanity; however the consequences of his actions resulted in violence and destruction. Another correlation between the two is that Frankenstein playing God (as he is defeating death) threatens religion as it insinuates that humans have the power and not God, and in the revolution the Church was under threat as the reform deprived them of power and encouraged liberal thinking. However the most important theme is the debate; is it the reform that causes destruction and devastation or is it peoples inability to accept something different? Is it the creature that causes destruction and devastation or is it peoples inability to accept something different? I believe the answer to both of these questions is peoples inability to accept something different, because if people were not afraid of change then they would have accepted the revolution and not created a reign of terror, and if people were not afraid of something alien and different then people would have treated the creature with some form of courtesy and consideration, thus avoiding infuriating the creature. Evidence from the text on this point is when a young boy free of prejudice and discrimination is confronted by the creature; ‘monster! Ugly wretch! You wish to eat me, and tear me to pieces – You are an ogre – let me go, or I will tell my papa. ‘ The creature had already explained that he had no intentions to hurt or harm the boy, but because the creature is different and alien, he is immediately associated with evil, and must be avoided. Mary Shelley creates a variety of interesting points throughout the novel; that we should except death and take solace in the fact that we will hopefully be reunited one day in heaven. Therefore we should not be saddened and try to control the natural process of life, but enjoy experience. Mary Shelley also warned the reader about the dangers of unknown science, and that even an experiment designed to help humanity can have disastrous consequences. However, the most inspiring point created was the connection between the French revolution and the novel. It opened the readers mind to the prejudice and discrimination that the human race evilly portray. Anything alien or different must be associated with evil, which is a fundamental flaw of society that is near impossible to eliminate. We are, as a race, extremely narrow minded. In the novel we failed to overlook the creature’s repulsive appearance and treated him with complete contempt and disdain. This story illustrates the intolerant and callous society, and no matter how considerate and selfless a person is, we will still torment and ridicule them if they are in any way different to ourselves. Therefore, I disagree that the creature is a fiend as although he is cursed with a grotesque appearance that does not make him a monster, and although he committed several fiendish acts he is not accountable for this as it is merely a consequence of humans disgraceful behaviour, however as the creature endures feelings of both compassion and rage, as he can distinguish between good and evil, and as he desires more than the basic necessities of hunger, shelter and thirst, I believe that the creature must be described as essentially human. Â