Saturday, September 7, 2019
Themes in Othello Essay Example for Free
Themes in Othello Essay Themes in Othello is that of deception, developed mostly through Iago, who is an arch-deceiver throughout the play. Because he is angry that Othello has passed over him for a promotion, he vows revenge. Playing upon Othelloââ¬â¢s jealousy, he deceives him into believing that Desdemona is having an affair with Cassio. He also deceives Roderigo, making him believe that Desdemona will tire of Othello and eventually be won by Roderigo. It is Iagoââ¬â¢s repeated deceptions that move the plot of the play forward to the ultimate climax and tragedy. Another minor theme of Othello is love, and the play can be considered a romantic tragedy. The play is romantic because it celebrates the marriage of two minds as embodied in Othello and Desdemona. They marry in spite of the protests of Desdemonaââ¬â¢s father, and she faithfully follows her husband wherever he is sent. Their romantic marriage, however, is ruined by the villainous machinations of Iago. Othello is eventually led to murder his beloved, turning the romantic play into a tragedy. A third minor theme of Othello revolves around appearance vs. reality. Iago has an honest face, which helps hide his deceitful soul. Othello appears to be strong and courageous, a leading general, but he is easily tricked into fearing that his wife is unfaithful. It appears that Desdemona has left her treasured handkerchief with Cassio; in reality, Emilia has taken it and Iago has planted in on Cassio. Because of Iagoââ¬â¢s trickery, it appears to Othello that Desdemona is involved with Cassio; in truth, she is innocent, loving her husband dearly. Throughout the play, Iago is instrumental in making sure that reality is disguised by appearances, which he manipulates. MOOD The predominant mood of the whole play is somber and tragic. Iago works his evil almost from the opening scene, and each new deception that he plans brings greater misery. The tragic gloom that he causes is only occasionally relieved by comedy, provided by Roderigo and the Clown.
Friday, September 6, 2019
Consider the View That Free
Consider the View That Free Will is an Illusion Essay You decide on the chocolate cake confident that you could have chosen the sandwich instead. You were free to do both, but as a matter of fact, you chose to eat the unhealthy option. But were you actually free to choose the unchosen alternative? Many philosophers think that free will is actually an illusion ââ¬â that the choice you actually made was inevitable. Schopenhauer, for example, argued that for a man to say that he could have chosen an alternative is analogous to water in a still pond saying it could be flowing. Yes, he said, the water could be flowing if that same water were in a river, but given that it is actually in a pond its stillness is inevitable. I will argue that the arguments that purport to show that free will is an illusion are weak, and that we have such a thing as free will. First let us look at the arguments for determinism (here I will understand the determinism being discussed to be hard determinism ââ¬â the view that our free will is illusory ââ¬â rather than the compatibilist idea that free will can exist alongside causal determinism). What makes you take the chocolate cake instead of the sandwich? We think that the chocolate taking is the result of our deliberation and that the motive for eating the chocolate cake overcame our desire to be healthy. But what determined or caused us to be the kind of being that preferred the one to the other? It was our overall character. But what caused this? We say it is our upbringing and our genes. Now did we decide upon our upbringing that started the casual chain of events that culminated in the taking of the chocolate? No, so there was no other action that was in fact possible. Think of a snooker ball falling into the pocket. What caused this to happen? It was the combination of its shape, the direction of the cue, and the nature of the table. These factors combined with the laws of physics made the event inevitable. Of course, the snooker ball was not logically required to go into the pocket. There could have been a gust a wind at the crucial moment, but then this other event would have been causally necessary. Other things can only happen if other things which cause these other things to happen occur. So whatever happens is determined. If this is true of snooker balls, why should it be not true of us as well? If we are physical beings, and our brains composed of physical stuff, why should I be not constrained by the same physical forces as everything else? The hard determinist says that there is no reason to believe that we are not subject, like the billiard ball, to the laws of nature. We feel like we could have chosen the sandwich, but given the physical facts about the situation the taking of the chocolate was inevitable. Of course, we could have taken the sandwich if the physical facts were different, but they werenââ¬â¢t! So free will ââ¬â the sense that we could have done otherwise in the same situation ââ¬â is an illusion say the hard determinists. We are not free. This is a radical thesis, and if accepted would result in a radical readjustment of our concept of ourselves. And it from this that my first argument comes. According to phenomenalism we should proceed according to this methodology: accept the appearances ââ¬â accept what you have the most warrant for believing. Descartes, for example, says we can be more philosophically assured of the existence of our own minds than the existence of the physical world. Hence his famous proposition: Cogito ergo sum. Why should the more doubtful propositions of science about the nature of the doubtable physical world take precedence over the immediate data of consciousness? Why should the philosophically disputable over-ride the philosophically indubitable? Physical determinists are committed to this doubtful methodology: let the world, which we cannot prove to exist, take precedence over the mental world whose existence we simply cannot doubt. The phenomenalist like Sartre says the mental appearances are indisputable. We certainly have the phenomenology of the appearance that we could have chosen otherwise. And it is from these certainties that we should proceed. So our freedom is here an inevitable part of our conception of ourselves and no argument from the outside world of physics can over-ride these certainties. Hereââ¬â¢s another argument against the acceptance of the idea that free will is an illusion. Kant says that ought implies can. In other words, we cannot be obliged to do something if it is not within our ability to do it. Someone may say that I ought to eliminate third world poverty ââ¬â that if I do not do so I am guilty of a neglect of duty. But this is unreasonable. It is not within my power to eliminate third world poverty, so it cannot be said that I ought to do so. Of course, if someone were to say that I ought to help to eliminate third world poverty, this is a reasonable ââ¬Ëoughtââ¬â¢ because I can do it. Ought then implies can. The argument proceeds from this presupposition and says that if Eric murders Sam we say that he ought not to have done so. He ought to have done differently ââ¬â he ought to have refrained from murder. But if determinism is true, then, Eric had no alternative open to him. He was caused by his nature, the laws of physics, and his environment to kill Sam. We cannot therefore say that he ought not to have done it. We cannot expect people to do things that are not within their power to do. Our moral beliefs then presuppose that determinism is false. If we are not free then a morality of oughts and duty is incoherent. Again, we could proceed phenomenologically on this ââ¬â we are more sure and have more warrant for our oughts than we have for our beliefs in determinism, so moral oughts should over-ride any belief we might be entertaining for determinism. Another argument against determinism says this: if I am caused to inevitably accept the conclusions of an argument then I cannot have been rational to accept the conclusions of the argument. If I am determinist I have to say that my belief in determinism was caused by physical processes. The determinist has to accept that it is true for his opponent. Both are caused by ignorant physical forces to accept their beliefs. But this is self-refuting. The determinist is in effect saying that there is no rationality, so we cannot be rational in accepting or rejecting beliefs. So the consistent determinist cannot say that he is offering reasons for accepting determinism; he must say he is putting in new causal inputs that cause a new belief state to emerge. This seems little better than irrational brain-washing! To conclude: belief in determinism is not warranted. It goes against our fundamental conceptions of ourselves and threatens to make morality meaningless. Moreover, determinism is self-refuting. It says of itself ââ¬ËThere is no rational reason for accepting me. ââ¬â¢ I cannot rationally accept that which has no rational reason for its justification.
Thursday, September 5, 2019
Natural product chemistry
Natural product chemistry Introduction Of Natural Product Chemistry In the beginning of organic chemistry was natural products chemistry. For a long period, up to the 1960s the structural studies of natural products served as the principle driving force for the discovery of new chemical reactivity. The introduction of spectroscopic techniques, however, removed much of the intellectual challenge involved in structure elucidation. Furthermore, natural products chemistry suffered a dramatic decline from the mid 1990s when major pharmaceutical companies disinvested in this area and switched to more rational combi-chem approaches. Nevertheless, the improvements in spectroscopic methods have historically stimulated natural products chemistry and the efforts to examine new compounds from unusual organisms rapidly and systematically. Natural products chemistry survived and began to flourish again in recent years also through chemical biology and chemical genetics and the realization that natural product structures often explore structural space unavailable t o combi-chem approaches. As a result, challenges for natural product chemists are not diminishing, they are just changing. Natural product chemistry turned to an interdisciplinary science, where the success of a chemist would only be possible in close collaboration with biologists, pharmacologists, and clinicists. Thus many novel biological activities such as beta-tubulin assembly inhibitors for example, could only have emerged from the natural products arena. Contents Of Natural Chemistry Steroids.- Terpenoids.- Fatty Lipids and Prostaglandins.- Alkaloid.- Amino Acids and Proteins.- Nucleic Acids.- Carbohydrates.- Plant and Insect Growth Regulators.- Phenolic Compounds and Natural Dyes.- Marine Natural Products.- Antibacterials.- Vitamins and Hormones. Natural product A natural product is a chemical compound or substance produced by a living organism found in nature that usually has a pharmacological or biological activity for use in pharmaceutical drug discovery and drug design. A natural product can be considered as such even if it can be prepared by total synthesis. These small molecules provide the source or inspiration for the majority of FDA-approved agents and continue to be one of the major sources of inspiration for drug discovery. In particular, these compounds are important in the treatment of life-threatening conditions. Natural sources Natural products may be extracted from tissues of terrestrial plants, marine organisms or microorganism fermentation broths. A crude (untreated) extract from any one of these sources typically contains novel, structurally diverse chemical compounds, which the natural environment is a rich source of. Chemical diversity in nature is based on biological and geographical diversity, so researchers travel around the world obtaining samples to analyze and evaluate in drug discovery screens or bioassays. This effort to search for natural products is known as bioprospecting. Animal sources Animals can sometimes be a source of new lead compounds. For example, a series of antibiotic peptides were extracted from the skin of the African clawed frog and a potent analgesic compound called epibatidine was obtained from the skin extracts of the Ecuadorian poison frog. Screening of natural products Pharmacognosy provides the tools to identify, select and process natural products destined for medicinal use. Usually, the natural product compound has some form of biological activity and that compound is known as the active principle such a structure can act as a lead compound (not to be confused with compounds containing the element lead). Many of todays medicines are obtained directly from a natural source. On the other hand, some medicines are developed from a lead compound originally obtained from a natural source. This means the lead compound: can be produced by total synthesis, or can be a starting point (precursor) for a semisynthetic compound, or can act as a template for a structurally different total synthetic compound. This is because most biologically active natural product compounds are secondary metabolites with very complex structures. This has an advantage in that they are extremely novel compounds but this complexity also makes many lead compounds synthesis difficult and the compound usually has to be extracted from its natural source a slow, expensive and inefficient process. As a result, there is usually an advantage in designing simpler analogues. The plant kingdom Plants have always been a rich source of lead compounds (e.g. morphine, cocaine, digitalis, quinine, tubocurarine, nicotine, and muscarine). Many of these lead compounds are useful drugs in themselves (e.g. morphine and quinine), and others have been the basis for synthetic drugs (e.g. local anaesthetics developed from cocaine). Clinically useful drugs which have been recently isolated from plants include the anticancer agent paclitaxel (Taxol) from the yew tree, and the antimalarial agent artemisinin from Artemisia annua. Plants provide a large bank of rich, complex and highly varied structures which are unlikely to be synthesized in laboratories. Furthermore, evolution has already carried out a screening process itself whereby plants are more likely to survive if they contain potent compounds which deter animals or insects from eating them. Even today, the number of plants that have been extensively studied is relatively very few and the vast majority have not been studied at all. The marine world In recent years, there has been a great interest in finding lead compounds from marine sources. Coral, sponges, fish, and marine microorganisms have a wealth of biologically potent chemicals with interesting inflammatory, antiviral, and anticancer activity. For example, curacin A is obtained from a marine cyanobacterium and shows potent antitumor activity. Other antitumor agents derived from marine sources include eleutherobin, discodermolide, bryostatins, dolostatins, and cephalostatins. The microbial world Microorganisms such as bacteria and fungi have been invaluable for discovering drugs and lead compounds. These microorganisms produce a large variety of antimicrobial agents which have evolved to give their hosts an advantage over their competitors in the microbiological world. The screening of microorganisms became highly popular after the discovery of penicillin. Soil and water samples were collected from all over the world in order to study new bacterial or fungal strains, leading to an impressive arsenal of antibacterial agents such as the cephalosporins, tetracyclines, aminoglycosides, rifamycins, and chloramphenicol. Although most of the drugs derived from microorganisms are used in antibacterial therapy, some microbial metabolites have provided lead compounds in other fields of medicine. For example, asperlicin isolated from Aspergillus alliaceus is a novel antagonist of a peptide hormone called cholecystokinin (CCK) which is involved in the control of appetite. CCK also acts as a neurotransmitter in the brain and is thought to be involved in panic attacks. Analogues of asperlicin may therefore have potential in treating anxiety. Other examples include the fungal metabolite lovastatin, which was the lead compound for a series of drugs that lower cholesterol levels, and another fungal metabolite called ciclosporin which is used to suppress the immune response after transplantation operations. Venoms and toxins Venoms and toxins from animals, plants, snakes, spiders, scorpions, insects, and microorganisms are extremely potent because they often have very specific interactions with a macromolecular target in the body. As a result, they have proved important tools in studying receptors, ion channels, and enzymes. Many of these toxins are polypeptides (e.g. Ãâ-bungarotoxin from cobras). However, non-peptide toxins such as tetrodotoxin from the puffer fish are also extremely potent. Venoms and toxins have been used as lead compounds in the development of novel drugs. For example, teprotide, a peptide isolated from the venom of the Brazilian viper, was the lead compound for the development of the antihypertensive agents cilazapril and captopril. The neurotoxins from Clostridium botulinum are responsible for serious food poisoning (botulism), but they have a clinical use as well. They can be injected into specific muscles (such as those controlling the eyelid) to prevent muscle spasm. These toxins prevent cholinergic transmission and could well prove a lead for the development of novel anticholinergic drugs. Traditional Medicine In the past, traditional peoples or ancient civilizations depended greatly on local flora and fauna for their survival. They would experiment with various berries, leaves, roots, animal parts or minerals to find out what effects they had. As a result, many crude drugs were observed by the local healer or shaman to have some medical use. Although some preparations may have been dangerous, or worked by a ceremonial or placebo effect, traditional healing systems usually had a substantial active pharmacopoeia, and in fact most western medicines up until the 1920s were developed this way. Some systems, like traditional Chinese medicine or Ayurveda were fully as sophisticated and as documented systems as western medicine, although they might use different paradigms. Many of these aqueous, ethanolic, distilled, condensed or dried extracts do indeed have a real and beneficial effect, and a study of ethnobotany can give clues as to which plants might be worth studying in more detail. Rhubarb root has been used as a purgative for many centuries. In China, it was called The General because of its galloping charge and was only used for one or two doses unless processed to reduce its purgative qualities. (Bulk laxatives would follow or be used on weaker patients according to the complex laxative protocols of the medical system.[2]) The most significant chemicals in rhubarb root are anthraquinones, which were used as the lead compounds in the design of the laxative dantron. The extensive records of Chinese medicine about response to Artemisia preparations for malaria also provided the clue to the novel antimalarial drug artemisinin. The therapeutic properties of the opium poppy (active principle morphine) were known in Ancient Egypt, were those of the Solanaceae plants in ancient Greece (active principles atropine and hyoscine). The snakeroot plant was well regarded in India (active principle reserpine), and herbalists in medieval England used extracts from the willow tree(salicin) and foxglove (active principle digitalis a mixture of compounds such as digitoxin, digitonin, digitalin). The Aztec and Mayan cultures of Mesoamerica used extracts from a variety of bushes and trees including the ipecacuanha root (active principle emetine), coca bush (active principle cocaine), and cinchona bark (active principle quinine). It can be challenging to obtain information from practitioners of traditional medicine unless a genuine long term relationship is made. Ethnobotanist Richard Schultes approached the Amazonian shamans with respect, dealing with them on their terms. He became a depswa medicine man sharing their rituals while gaining knowledge. They responded to his inquiries in kind, leading to new medicines.[3] On the other hand Cherokee herbalist David Winston recounts how his uncle, a medicine priest, would habitually give misinformation to the visiting ethnobotanists. The acupuncturists who investigated Mayan medicine recounted in Wind in the Blood had something to share with the native healers and thus were able to find information not available to anthropologists.[4] The issue of rights to medicine derived from native plants used and frequently cultivated by native healers complicates this issue. Isolation and purification If the lead compound (or active principle) is present in a mixture of other compounds from a natural source, it has to be isolated and purified. The ease with which the active principle can be isolated and purified depends much on the structure, stability, and quantity of the compound. For example, Alexander Fleming recognized the antibiotic qualities of penicillin and its remarkable non-toxic nature to humans, but he disregarded it as a clinically useful drug because he was unable to purify it. He could isolate it in aqueous solution, but whenever he tried to remove the water, the drug was destroyed. It was not until the development of new experimental procedures such as freeze drying and chromatography that the successful isolation and purification of penicillin and other natural products became feasible. Synthesis Not all natural products can be fully synthesized and many natural products have very complex structures that are too difficult and expensive to synthesize on an industrial scale. These include drugs such as penicillin, morphine, and paclitaxel (Taxol). Such compounds can only be harvested from their natural source a process which can be tedious, time consuming, and expensive, as well as being wasteful on the natural resource. For example, one yew tree would have to be cut down to extract enough paclitaxel from its bark for a single dose. Furthermore, the number of structural analogues that can be obtained from harvesting is severely limited. A further problem is that isolates often work differently than the original natural products which have synergies and may combine, say, antimicrobial compounds with compounds that stimulate various pathways of the immune system: Many higher plants contain novel metabolites with antimicrobial and antiviral properties. However, in the developed world almost all clinically used chemotherapeutics have been produced by in vitro chemical synthesis. Exceptions, like taxol and vincristine, were structurally complex metabolites that were difficult to synthesize in vitro. Many non-natural, synthetic drugs cause severe side effects that were not acceptable except as treatments of last resort for terminal diseases such as cancer. The metabolites discovered in medicinal plants may avoid the side effect of synthetic drugs, because they must accumulate within living cells. Semisynthetic procedures can sometimes get around these problems. This often involves harvesting a biosynthetic intermediate from the natural source, rather than the final (lead) compound itself. The intermediate could then be converted to the final product by conventional synthesis. This approach can have two advantages. First, the intermediate may be more easily extracted in higher yield than the final product itself. Second, it may allow the possibility of synthesizing analogues of the final product. The semisynthetic penicillins are an illustration of this approach. Another recent example is that of paclitaxel. It is manufactured by extracting 10-deacetylbaccatin III from the needles of the yew tree, then carrying out a four-stage synthesis. Use Of Natural Product Ayurveda Chinese medicine Ethnobotany Journal of Natural Products Pharmacognosy Phytotherapy Secondary metabolite During the last few decades, research into natural products has advanced tremendously thanks to contributions from the fields of chemistry, life sciences, food science and material sciences. Comparisons of natural products from microorganisms, lower eukaryotes, animals, higher plants and marine organisms are now well documented. This book provides an easy-to-read overview of natural products. It includes twelve chapters covering most of the aspects of natural products chemistry. Each chapter covers general introduction, nomenclature, occurrence, isolation, detection, structure elucidation both by degradation and spectroscopic techniques, biosynthesis, synthesis, biological activity and commercial applications, if any, of the compounds mentioned in each topic. Therefore it will be useful for students, other researchers and industry. The introduction to each chapter is brief and attempts only to supply general knowledge in the particular field. Furthermore, at the end of each chapter t here is a list of recommended books for additional study and a list of relevant questions for practice. Combined with pharmacological screening, natural products chemistry has always provided highly useful leads for drug discovery. The searches for new biologically active compounds are most often based on hints coming from ethnobotany but there are still a huge number of unstudied plants, not to speak of mushrooms, marine organisms, insects, and microorganisms. There is a wealth of molecular diversity out there, waiting to be discovered and utilized. The central issue of such type of studies, structure elucidation, although often believed to be trivial, is still a process full of adventure, discovery, and even unavoidable pitfalls. Thus structure elucidation has still much to offer, especially when combined with biological tests. Chemistry Central Journal is waiting for your results to publish. Besides the classic studies connected to pharmacological activities, new developments challenge natural products chemists, such as metabolomics, the large-scale phytochemical analysis in the functional genomics era. Metabolomic requires from a natural product chemist brilliant knowledge of modern analytical techniques and chemometry and close collaboration with biochemists and biologists. Chemical ecology, too, could not advance properly without natural product chemistry. Approximately 60% of the worlds population relies almost entirely on plants for medication. However, if phytopharmaceuticals want to be regarded as rational drugs, they need to be standardized and pharmaceutical quality must be approved. For this reason, another important task for natural products chemistry is connected to standardization: to develop proper analytical methods of quality control, to make sure that medicines obtained from natural sources are safe and of reproducible efficacy. The publication of natural product research results in an open access journal is of great importance with respect both to research activities and to effective use of natural resources, removing both price and permission barriers. It is also important to authors, giving them the opportunity to publish their results where they will be most easily accessed by those who mostly need them. Natural Product Chemistry for Drug Discovery provides a comprehensive summary of where natural product chemistry is today in drug discovery. The book covers emerging technologies and case studies and is a source of up-to-date information on the topical subject of natural products. The authors, all experts in their respective fields, provide compelling arguments as to why naturel products should be considered important tools in the drug discovery process. The book will appeal across the board from scientists to professionals, postgraduates and industrial chemists. The case studies selected for inclusion highlight recently marketed drugs and development candidates that have been derived from natural products. These real-life examples show how new technologies, such as advances in screening, isolation, dereplication and prefractionation, have significantly enhanced the discovery process. Introduction Of Synthetic Chemistry In primitive societies, even today, clothes are cleaned by beating them on rocks near a stream. Certain plants, such as soapworts, have leaves that produce sapions, chemical compounds that give a soapy lather. These were probably the first detergents people used. If you look up detergent in a dictionary it is simply defined as cleaning agent. During the last two to three decades, however, the word detergent has tended to imply synthetic detergent, or syndet for short, rather than the older soap. In fact, commercial formulations consist of a number of components, and we shall use the term surface-active agent, or its abbreviation surfactant, to describe the special active ingredients that give detergents their unusual properties. Soap, by this definition, is a surfactant. In fact, it is the oldest one and has been in use for over 4500 years. Some soap manufacture took place in Venice and Savona in the fifteenth century, and in Marseilles in the seventeenth century. By the eighteenth century, manufacture was widespread throughout Europe and North America, and by the nineteenth century the making of soap had become a major industry. As a matter of fact, soap became a detergent in 1907 when a German company put the product Persil on the market. In addition to the carboxylic acid soap, Persil contained sodium perborate, sodium silicate and sodium carbonate. Hence perborate + silicate = PERSIL. Synthetic Surfactant or Soap? You may well ask why soap, which served well for so many years, was eventually displaced. Soaps are cheap and they are manufactured from a renewable source, whereas many of the synthetic detergents are made from petrochemicals. Soaps are also biodegradable; that is, they are readily broken down by bacteria, and thus they do not pollute rivers. However, due to their gelling properties, soaps do have a greater tendency to clog sewerage reticulation systems than synthetic detergents. The grease trap of a non-sewered house was often laden with soap. But the most important reason for the displacement of soap is the fact that, when a carboxylic acid soap is used in hard water, precipitation occurs. The calcium and magnesium ions, which give hardness to the water, form insoluble salts with the fatty acid in soap and a curd-like precipitate occurs and settles, of course, on what ever is being washed. By using a large excess of soap, it is possible to redisperse the precipitate, but it is ext remely sticky and difficult to move. This problem with soap can be demonstrated by a simple experiment in which a concentrated solution of hard-water salts is added to a 0.1% solution of soap and also to a 0.1% solution of synthetic surfactant. The soap precipitates, but the synthetic surfactant remains clear because its salts are water soluble. You may live in an area where the water is extremely soft. But calcium and magnesium ions are present in the dirt that you wash out of your clothes, so that some precipitation still occurs if soap is used, and gradually deposits are built up in the fabric. There are other disadvantages with soap; it deteriorates on storage, and it lacks cleaning power when compared with the modern synthetic surfactants, which can be designed to perform specialised cleaning tasks. Finally and very importantly from a domestic laundry point of view, soap does not rinse out; it tends to leave a residue behind in the fabric that is being washed. A residue gradually builds up and causes bad odour, deterioration of the fabric and other associated problems. Whats the Difference? Whats the difference between a surfactant and soap? In general terms, the difference can be likened to the difference between cotton and nylon. On the one hand, soap and cotton are produced from natural products by a relatively small modification. On the other hand, synthetic surfactants and nylon are produced entirely in a chemical factory. Synthetic surfactants are not very new, either. Back in 1834 the first forerunner of todays synthetic surfactants was produced in the form of a sulfated castor oil, which was used in the textile industry. The development of the first detergents in an effort to overcome the reaction of soaps with hard water provides a good illustration of one of the standard chemical approaches. If a useful substance has some undesirable property, an attempt is made to prepare an analogue, a near chemical relation, which will prove more satisfactory. The petroleum industry had, as a waste product, the compound propylene, CH3-CH=CH2, which used to be burnt off. By joining four of these propylene molecules together and if benzene is attached at the double bond, the resulting compound reacts with sulphuric acid. Then sodium hydroxide is added to neutralise the sulfonic acid and a sodium salt is obtained. The new substance is closely related to an ordinary soap, and is an excellent detergent. Detergent Foam Level The relationship between foaming power and detergency has always been of interest, and foaming power has become associated in many consumers minds with high detergent power. The first liquid detergent on the Australian market was Trix. It was non-foaming, so was soon replaced because of consumer resistance. However, it is generally conceded by detergent technologists that foam height has no direct relationship to cleaning power in ordinary fabric washing systems. In systems where the amount of washing fluid is low, foam may play an important role. The individual foam films tend to take up and hold particles of soil that have been removed from the item, preventing them from being re-deposited and allowing them to be washed or scraped away. Front loading washing machines work by bashing clothes against the side of the tub the high tech version of beating clothes on rocks. Front loaders clean clothes better than top loaders, but only if a low-suds detergent is used, because the suds cushion the impact and reduce the cleaning action. Chemical Characteristics Of Synthetic Chemistry Synthetic detergents dissolve or tend to dissolve in water or other solvents. To enable them to do this, they require distinct chemical characteristics. Hydrophilic (water loving) groupings in their molecular structure, and hydrophobic (water hating) groupings, help the detergent in its ââ¬Å"detergencyâ⬠action. This detergency depends on the balance of the molecular weight of the hydrophobic to the hydrophilic portion. This is called the HLB value, and can range from 1 upwards. HLB is Hydrophilic-Lypophilic Balance. As the 0HLB value increases, the product can tend towards being a paste or solid. The lower number HLB values tend to be less water soluble, and more oil soluble. The higher the HLB the more water soluble the product. Mixtures of low and high HLB detergents produce good detergents to handle oil, fat and grease, the higher HLB detergent helps solubilise the less water soluble, low HLB detergent into an aqueous system.
Wednesday, September 4, 2019
Eugenics in America Essay -- Sociology Essays Research Papers
Eugenics in America Eugenics profoundly impacted the culture of the twentieth century. Coined in 1893 by Sir Francis Galton, it studied the heredity and selection of favorable traits. Born out of the social tumults of the late nineteenth century, it represented the Western eliteââ¬â¢s attempt to protect itself from so called ââ¬Å"inferiorâ⬠cultures of the colonies and ââ¬Å"new waveâ⬠immigration. The late eighteenth century was a turbulent time throughout America. An influx of immigrants packed into massive cities such as New York and Chicago. As opposed to previously northern European immigration, a wave of ââ¬Å"newâ⬠immigration in the 1890ââ¬â¢s brought immigrants from southern and eastern Europe, who vastly differed culturally and religiously from their northern European counterparts. Some immigrants brought radical ideologies with them such as Marxism, anarchism, and monarchism, which completely differed from the American ideals of free markets, elections, and democracy. The massive influx of people crowded into sordid city blocks brought a slew of social problems such as alcoholism, poverty, murder, rape, and violence. Coupled with falling birth rates among the elite and rising birth rates among immigrants, Anglo-culture sought out an answer to defend itself against the ââ¬Å"siegeâ⬠of ââ¬Å"inferiorâ⬠cultures. The late nineteenth century saw the rise of ââ¬Å"eugenicsâ⬠throughout academia. Founded by Francis Galton (the word came into existence in 1893), eugenics was the study of the selection of favorable traits in society. Deeply influenced by Darwin, Galton published his first eugenicist tract in 1865 Hereditary Genius, which posited that manââ¬â¢s strength, talent, and skill is passed down genetically fr... ...ââ¬Å"degenerateâ⬠or ââ¬Å"inferior.â⬠Popularized in the early twentieth, it manifested itself throughout American culture from textbooks to advertisements for household goods. Eugenics represented American cultureââ¬â¢s vain attempt to grapple with non-western European cultures and cope with a quickly evolving social landscape. Bibliography Dolan DNA Learning Center, Cold Spring Laboratory, http://www.eugenicsarchive.org/eugenics/ School of Mathematics and Statistics at St. Andrewââ¬â¢s University http://www-gap.dcs.st-and.ac.uk/~history/Mathematicians/Galton.html Pucker, Johnathan, History in the Influences of Intelligence Theory and Testing http://www.indiana.edu/~intell/galton.html Linden, Jeremy http://students.vassar.edu/jelinden/galton.htm McCleymer, Professor at Assumption College http://www.assumption.edu/users/McClymer/his394/contagion.html
Tuesday, September 3, 2019
Lets Put an End to Parking Problems! Essay -- Argumentative Persuasiv
Let's Put an End to Parking Problems! Ã I would like to see the parking and traffic crunch on and around this campus eased. Unless a student arrives before 8 o'clock in the morning or in the afternoon, cruising the parking lots or streets for a place to park is routine. Even buying a parking sticker does not mean you will have the privilege of a space. Competition for spaces during the rush hours of 9 A.M. to 11 A.M. is cutthroat. Would-be parkers stake out sections of a parking row and sit in their cars hoping someone in their section will leave. The other ploy is to try and catch someone who is just walking back to their car in order to plead for that space. lf these tricks fail, the only thing left is to park far away on the street and walk.Ã Ã There would seem to me to be several ways to help the situation. The most obvious of these solutions is to increase the amount of parking available. Another solution is to make car pooling more attractive. Set aside space in a convenient lot for these cars with three or more occupants. Perhaps another incentive...
Monday, September 2, 2019
Word-association in Oedipus The King :: Oedipus the King Oedipus Rex
Word-association in Oedipus The King à à à à Let us play a little game, shall we? We have all played this at one point in our lives; it's the word-association game. Think red- you may think apple. Now think green- you may once again think apple. Wait a minute, how can that be? How can two words that are unrelated have the same picture in the mind of an individual? This is the basic idea of perception. Now let us apply this basic concept to the text of Oedipus Tyrannus. The main character, Oedipus, has lived his entire life with basic preconceived notion of his own existence. Sophocles manipulates the audience's perception of Oedipus through oral dramatic presentation. "Lacan insists that dialogue is the place where a certain subject comes into being, or perhaps more properly, where the subject comes into being in a certain kind of way" (Lee 38) Jacques Lacan deals with the perception of individuals as well. However Lacan's perceptions are those dealt with in the mind of his subjects. Let us introduce Oedipus, as the subject, to Lacan the psychoanalyst. Now that the two have met in our minds' we can continue with the forum of one man's perception, Lacan's, of another man's life, Oedipus's. Lacan has two complex theories. The first is the mirror theory. This theory deals with the internal world of the subject, and the phases of the conscious as well as the unconscious mind. The second is the inability to communicate one's desires adequately through the usage of oral communication- language. In both of these simplified concepts we will delve into the mind, and the actions of Oedipus the character. Let us first discuss the mirror stage, with application to Oedipus the man. Within the mirror stage there are five phases. The first of which is the "fragmented body stage." While existing in this stage man is unaware of himself. In this dark, 'lost' state man is unaware of his surroundings as well as himself as a being. Oedipus prior to the opening of the play lives his entire life in this "fragmented" state; he is completely unaware of himself and his actions on his society. In this state Oedipus is caught up in the pomp of his title. The role of King carries an elevated perception of an idealized life (Lee 19). The next movement in the five phases is the "spatial identity.
Sunday, September 1, 2019
No one knowingly does evil: an essay on the Socratic principle
The contention that no one knowingly does evil is one of the most fundamental principles championed by Socrates. The very essence of this Socratic principle dwells on the assumption that if a man understands very well that such and such acts are wrong or result to evil, or such that if a man is indeed aware in the first place that this action is wrong in the strictest sense of the word, then that man will tend to revert himself away from committing the act. Socrates stalwartly advances his pivotal idea that men in general cannot, in any conceivable manner, transform man into being fully wise or utterly foolish.Rather, men are inclinedto perform actions at an unfixed and random way, with no great propensity to be inclined to do more evil or to do more good. Consequently, an inexhaustible capability for performing either good or bad conducts is what men do not fundamentally possess. Another principal feature of Socratesââ¬â¢ thoughts is his claim that knowledge is directly associate d to that which is good and that ignorance is tied to that which is evil. Thus, it can be clearly observed that by claiming that no one knowingly does evil what is being meant is that to know and understand oneââ¬â¢s actions is to understand that which has goodness.Since ignorance is significantly affixed to evil, Socrates observes, then, that no one knowingly does evil. In instances where man acts, it is immaterial for one to put great emphasis on the goodness or evilness of the action itself. What one should all the more consider is whether such actions are either within the proximity of being just or unjust and not necessarily that of being good or evil. In general, what Socrates is trying to point out is that the very causes of evil acts can ultimately be drawn from ignorance. For example, revulsion of one person to another person results from misapprehension, from ignorance of the related facts.Further, the Socratic assertion that no one knowingly does evil refutes normal re lativism for a few several points. Given such Socratic principle, it implies that it applies to all men who have the innate capacity to act. Likewise, to assert that no one knowingly does evil is to assert as well the claim that human beings by nature cannot be consciously aware that they are doing evil and that, instead, they assume that they are acting in order to amplify pleasure. The term ââ¬Å"no oneâ⬠in the phrase obviously refutes any relative conception of the principle since ââ¬Å"no oneâ⬠refers to that which is universal.To have relative views, then, on what actions count as evil and good is to essentially refute the claim that no one does evil voluntarily and willingly, and vice versa. Several contemporary counter-examples can be given to attempt at refuting the Socratic principle. Apparently, suicide, terrorism and sadism all have one thing in common in the context of Socratesââ¬â¢ principle no one knowingly does evil: they purport to exemplify cases whe rein human beings appear to be capable of doing evil with their knowing.All these three may in fact provide crucial grounds for claiming that men have the potential and the actual capacity to inflict harm and do evil while they are fully aware of these actions. However, we might go on to argue that men in these instances are ignorant of the good. Yet, even if they are ignorant of the good, it does not necessarily follow that they know sadism, suicide and terrorism as evil deeds for the fact that no one identifies what is good without actually noting those which are evil or have the actions which have the propensity to result in evil.Thus, these actions could not have been evil in the first place if one has no sense of what it is that is deemed to be good. It might be held valid and true that people who engage themselves in these actions have a leaning towards the evil as others may view them to be, but nevertheless these very people who are a part of the actions are ignorant of the evil that they might have been doing. This is pegged on the presupposition that men have the mental framework that the things they do are aimed at obtaining that which incites pleasure.For the most part of the claims of Socrates, there are hardly any strong refutations which might prove to be callous enough to dismantle the ancient philosopherââ¬â¢s arguments. There is a deep sensibility in Socratesââ¬â¢ dialogues with his fellowmen in the Apology as with the other parts of Platoââ¬â¢s Republic such that, with the Socratic method of inquiry, one arrives at an understanding about oneââ¬â¢s little knowledge, that much is left to be understood and that only through a removal of oneââ¬â¢s ignorance can one begin to achieve genuine knowledge.
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