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The Role of Thermodynamics in Pharmacy, 2002.
A report into how essential thermodynamics is to pharmaceutical scientists.
3,181 words (approx. 12.7 pages), 5 sources, MLA, £ 58.95
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Abstract
This paper examines how fundamental the principles of thermodynamics are to pharmacy. The paper covers the topics of Gibbs free energy change, heat of formation, partial molar free energy, energy change and entropy, and discusses how all these are important in pharmaceutics in deciding drug delivery and dosage form. The paper presents the reader with a clearer insight into how important the above are, with extensive explanations into the three laws of thermodynamics and how they all help the modern day pharmaceutical scientist. Many of the complicated calculations involved in thermodynamics are exemplified through examples.
From the Paper
"A pharmacist is regarded as a professional scientist. Thus he is expected to know more than ever, is a thorough knowledge of thermodynamics. This discipline forms a rudimentary backbone of most of the material sciences as many other disciplines do ?borrow? heavily from this. 1,3 In studying thermodynamics, it attempts to integrate the factual knowledge of pharmacy and it aids the pharmaceutical scientist to predict the solubility, stability, feasibility, compatibility and biological action of drug products fairly accurately. Processes such as partitioning of solutes between immiscible solvents, the solubility of drugs, micellisation and drug-receptor interaction can all be treated in thermodynamic terms. 1Thermodynamics is concerned with the quantitative relationships between heat and other forms of energy, including mechanical, chemical, electric and radiant energy. 1The main feature to remember in the study of thermodynamics is that it is not possible to know the absolute value of the energy of a system but it is possible to record changes in energy that happen when a system undergoes transformation."
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Gas Chromatography, 2000.
A definition, general principles, apparatus used, sampling, types and conductivity detectors.
1,350 words (approx. 5.4 pages), 2 sources, £ 29.95
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From the Paper
"Gas chromatography is a method for the separation and analysis of complex mixtures of volatile organic and inorganic compounds (1:666). Most compounds with boiling points less than 250oC (480oF) can be analyzed using this technique. This paper will describe the apparatus used for gas chromatography, the principles on which it works, how a thermal conductivity detector works in gas chromatography, and whether or not it can be used with a sample of potassium t-butoxide.
General Principles of Gas Chromatography
There are two types of gas chromatography: gas-liquid chromatography, where the sorbent is a nonvolatile liquid called the stationary liquid phase, coated as a thin layer on an inert, granular solid support; and gas-solid chromatography, where the sorbent is a granular solid of large surface area (1:666). The..."
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Effects of Alcohol on Taste and Smell, 2000.
A fefination of alcohol and analysis of its impact on two senses.
1,125 words (approx. 4.5 pages), 7 sources, £ 24.95
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From the Paper
"Effects of Alcohol on Taste and Smell
Introduction
The purpose of this paper is to examine the effects of alcohol on people?s perception of taste and smell. The paper begins with a brief description of the impacting factor (alcohol) and how it operates. It then goes on to discuss the affects of alcohol at the first and second levels of perception of taste and smell. The final section of the paper presents a several conclusions formulated on the basis of the reviewed literature.
The Impacting Factor: Alcohol
Definition and Operation
Alcohol is the term used to refer to any class of organic compounds characterized by one or more hydroxyl (OH) groups attached to..."
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Reducing Porosity in Brass, 2000.
A technical examination of methods of reduction, history, phase diagrams, density, hardening and more.
2,925 words (approx. 11.7 pages), 14 sources, £ 65.95
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Abstract
Matrix management is associated with a matrix organizational form. A matrix form of organization is an organizational structure with two or more (a) channels of command, (b) lines of budget authority, (c) sources of performance reward, and (d) so forth.
From the Paper
"Methods of Reducing Porosity In Brass
Introduction. Matrix management is associated with a matrix organizational form. A matrix form of organization is an organizational structure with two or more (a) channels of command, (b) lines of budget authority, (c) sources of performance reward, and (d) so forth. A lack of maximal density, or some porosity, must exist in the metals' lattice structure or must be introduced in the alloying process. Explored here are methods metallurgists may use to minimize porosity in brass.
Brass. A useful alloy of two metals, copper and zinc (9:166), brass has been formed for cultural uses and ornamentation since the 13th century BC (1:9). The term, brass, indicates any of an infinite possible set of mixes of "copper-..."
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Beta Carotene, 1999.
Examines the structure, chemistry and biological activity, focusing on antioxidant and anti-carcinogenic properties in animal systems.
1,575 words (approx. 6.3 pages), 25 sources, £ 34.95
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Abstract
Examines the structure, chemistry and biological activity, focusing on antioxidant and anti-carcinogenic properties in animal systems.
From the Paper
"Beta Carotene
The carotenoids as a group, and specifically the beta carotenes, are known to serve a variety of functions in living cells. Presented here is an overview of the structure, chemistry, and biological activity of beta carotene, with emphasis on its capacity as an antioxidant and anti-carcinogen in animal systems.
Beta carotene is a member of a class of pigments called carotenoids, which occur naturally in plants and are found as well in animals. A precursor of vitamin A, also called provitamin A, it is found as an orange-red pigment in terrestrial plants, algae and some marine mammals. After purification, it appears as ruby-red crystals, easily oxidized on contact with air, with MP 184 degrees, MW 536.44. It is insoluble in water, slightly soluble in alcohol, soluble in chloroform, carbon disulfide, ether and benzene. Its ..."
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Carbohydrates, Lipids & Proteins, 1997.
Examines role of these carbon compounds in human diet & nutrition, related to organic chemistry.
2,025 words (approx. 8.1 pages), 8 sources, £ 45.95
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From the Paper
"Organic chemistry is the study of carbon compounds. Carbon compounds are central to the existence of every life form on earth. They make up the muscles of animals and human, the stems and leaves of plants, the molecules that transfer genetic information, protective clothing, hydrocarbons that breakdown to provide the energy for transport, and perhaps most important the food products for nutrition. In this paper, aspects of the relationship between organic chemistry and the three major food groups - carbohydrates, lipids and proteins - are explored.
An enormous amount of time and energy is spent preparing and eating the food that sustains and maintains human health. Consuming food is pleasurable and culturally significant, as exemplified by the holiday meals at Christmas, Hanukah, and the celebrations at wedding receptions. As a result of the abundance.."
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Friedrich Wohler, 1996.
Career, major concepts & discoveries of 19th Cent. German chemist.
2,250 words (approx. 9.0 pages), 15 sources, £ 50.95
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From the Paper
"Many fundamental concepts in chemistry can be traced back to Friedrich W?hler. A mild-mannered scientist, W?hler's discoveries revolutionized the understanding of organic chemicals. His artificial synthesis of urea eventually led to the overthrow of the theory of vitalism. In addition, W?hler contributed to ideas on isomerism and organic radicals. His work has ultimately had a great influence on the development of many fields of scientific endeavor.
A quiet, gentle person, Friedrich W?hler combined his "passion for chemistry" with a "great love of the open air, the beauties of nature and of all living things" (Findlay, 1965, pp. 323-324). Indeed, that branch of chemistry dealing with compounds of carbon is widely considered to have been started by..."
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Polyvinyl Chloride, 1996.
Development of this plastic & uses in industry & home, physical properties, manufacture, environmental issues, polymerization, costs.
2,025 words (approx. 8.1 pages), 7 sources, £ 45.95
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From the Paper
"Compared to most other materials, plastics have been introduced relatively recently. In fact, many of the major developments in plastics technology have occurred over the last 50 years. One plastic that currently finds widespread application in the construction industry is polyvinyl chloride (PVC). Although PVC has been around for over 100 years, it wasn't developed commercially until about the 1930s. The pure resin consists of a linear polymer. The compound's chlorine atoms cause considerable inter-chain attraction. Hence, in its pure state, the material is hard and rigid. With modifying agents, however, PVC can be softened to produce an entire array of flexible products. Indeed, the substance may be the most versatile of the plastics. PVC is currently found in cable..."
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Chemical Synthesis of Peptides, 1996.
Discovery, process, history, techniques, properties, side effects.
2,250 words (approx. 9.0 pages), 11 sources, £ 50.95
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From the Paper
"Peptides were first synthesized around the turn of the century. During the following decades, the compounds found many applications. At present, both solid and liquid phase methods may be used to chemically formulate peptides. The formation of a peptide bond requires both activation and protection. Although these processes have a long history, researchers continue to search for better coupling reagents and improved protecting group strategies.
Curtius (1881) and Fischer (1902) were the first to synthesize simple peptide derivatives (2:1-8). About that time, Hofmeister (1902) and Fischer (1906) additionally recognized that proteins actually consist of amino acids linked together by amide bonds. Subsequent peptide research generally involved the..."
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Empirical Formula, 2002.
A laboratory report using an empirical formula to find a compound created inside the crucible.
1,000 words (approx. 4.0 pages), 0 sources, APA, £ 22.95
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Abstract
he paper is written in the form of a laboratory report. The purpose of the experiment was to use an empirical formula in order to find a compound which has been created inside a crucible. The paper shows the procedure in which the experiment was done as well as its outcome. Flow charts, tabulated results and mathematical calculations are also included in the paper.
From the Paper
"The importance of safety precautions is extremely important in trying to maintain a safe and healthful research environment. When working with all extremely hot metals with your hands, gloves should be worn at all times. The temperatures of these metals or ?hot objects? absorb heat and could cause damage to the skin if touched. Without the use of gloves, hands can be severely burnt. One mistake or foolish act could cause much pain and suffering to students in the laboratory. People who do not handle hot objects carefully can get their nerves burnt off on their finger tips and could possibly never feel again. It is not worth taking a risk of not using gloves when applicable. Everyone wants to be safe in the laboratory so it is important to be aware and cautious. A safe laboratory is a safe life."
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Nitric Oxide, 2001.
Technical discussion of the discovery of how nitric oxide acts in the human body. Its value in treating cardiovascular disease.
2,700 words (approx. 10.8 pages), 13 sources, £ 60.95
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From the Paper
"In 1998, three American scientists were awarded the Nobel prize for Physiology and Medicine for their discovery that nitric oxide, a common gas in air pollution, transmits signals within the human body (Maugh, 1998). The discovery was hailed as one of the most important in the history of cardiovascular medicine, and was predicted to lead the way to treating high blood pressure and heart attacks. It led to the development of Viagra, to a new treatment for newborns with dangerously high blood pressure in their lungs, and to drugs for the treatment of shock.
"The signaling function of nitric oxide influences virtually every organ system in the body. The discovery that nitric acid produced by one cell could alter the function of other cells is an entirely new principle for signaling in biological systems...."
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Quality Initiatives in the Pharmaceutical Industry, 2002.
An analysis of the enormous demands placed on the pharmaceutical industry by the public and government agencies.
2,980 words (approx. 11.9 pages), 7 sources, MLA, £ 55.95
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Abstract
This paper describes the pharmaceutical industry's role as one of the largest contributors to economic growth in the United States. It illustrates the tremendous pressure the pharmaceutical industry is under, to meet the increasing demands for their product and maintain the quality standards of the regulatory agencies. The writer explains why it is in the best interest of the industry to attempt to maintain the high standards placed on them.
From the Paper
"According the US Business Reporter (2002), annual spending on prescription drugs is expanding at close to 14% on and annual basis. Several companies and drugs have led this increase, particularly Warner-Lambert's Lipitor, Eli Lilly's Zyprexa, Monsanto/ Pfizer's Celebrex, and Merck's Vioxx (US Business Reporter, 2002). The same article notes that the pharmaceutical industry typically operates on a 14-15% profit margin. This makes the pharmaceutical industry one of the largest contributors to economic growth in the Untied States."
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The Effects of a Neurotoxin on the Mammalian Brain, 2000.
A paper which studies the effects of the Superfund Neurotoxin Methylazoxymethanol (MAM) on brain dendritic spine density in long hooded Evans Rats Rattus norvegicus.
2,100 words (approx. 8.4 pages), 11 sources, APA, £ 41.95
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Abstract
The paper shows that in the study of structural development in the brain there have been several proposed biomarkers for quantifying brain plasticity. These include but are not limited to cortical thickness, dendritic length and branching, expression of neuronal proteins, and the presence of DNA adducts. The paper discusses the theory that a measure of brain plasticity emerging late in embryonic development will be a very sensitive biomarker for detecting subtle damage suffered by brain cells during earlier stages of brain development not detectable by other means. The paper shows that to test this, the effects of a neurotoxin on the late developing dendritic spines were studied. A significant decrease in spine density was observed as the neurotoxin, methylazoxymethanol, increased. The author of the paper shows how the implications are widespread in the study of neuro-degenerative disease.
From the Paper
"Fifty years ago, Donald Hebb demonstrated that the conditions under which laboratory rats were housed could significantly affect their performance in a variety of complex spatial tasks later in life (1). The complex environment rearing paradigm has been valuable in assessing plasticity of a variety of brain components including cerebral cortical microvasculature, astrocyetic morphology, dentritic branching patterns, synaptic number, and synaptic structure are all affected by complex environment rearing (2). It has been suggested that multiple synaptic contacts (spines) may play a role in the spread of the additive effect of learning known as potentiation, among neighboring unstimulated neurons. A lack of these spines and their connection with boutons of neighboring neurons could then result in a decrease in the capacity for learning. Some recent work has indicated that the presence of multiple synaptic contacts may be altered by experience. Most of this research has focused on structural changes in the hippocampus. Dendrtic spines show great variability in structure and connectivity, both within and across brain structures, including 10-fold differences in length and diameter as well as variations in the number of branches and spines per dendrite."
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Hemoglobin, Oxygen Transport and Nitric Oxide, 2001.
This paper presents electron paramagnetic resonance and oxygen binding studies of -nitrosyl hemoglobin - a novel oxygen carrier having NO (Nitric Oxide) assisted allosteric functions.
1,345 words (approx. 5.4 pages), 3 sources, APA, £ 28.95
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Abstract
This paper shows that Nitric Oxide (NO) is a very popular compound to investigate in the scientific community today. It is physiologically ubiquitous as a potent vasodilator, neurotransmitter, and immuno-active agent at low concentrations and it is produced and recycled in the respiratory tract to regulate the airway. This paper discusses in detail the mechanism behind oxygen binding and release by hemoglobin as it relates NO bound to the Hemoglobin. The oxygen affinity dynamics of native Hemoglobin and nitrosylated Hb are compared. The research also reveals that although NO has a much higher affinity than oxygen or carbon monoxide for Hemoglobin, NO behaves differently than these other ligands and is not as toxic to normal Hb oxygen binding as previously assumed.
From the Paper
"Small, unicellular aerobic organisms can obtain oxygen required for metabolism by simple diffusion from the environment. Most multicellular organisms have too great a surface area and many cells not in contact with the environment. They require circulatory systems that transport oxygen from gas-exchange organs to other tissues. In vertebrates, oxygen is bound to molecules of Hemoglobin (Hb) or transport in Red Blood Cells. Mammalian Hemoglobin is a tetramer, consisting of four polypeptide chains; two a and two b. Six ligands are coordinated to the ferrous iron, with the ligands in octahedral geometry around the metal cation (figure 1). In aqueous solution, free heme does not does not reversibly bind oxygen. Instead the Fe(II) is rapidly oxidized to Fe(III) when it gives up an electron to oxygen. The quaternary structure of hemoglobin prevents formal transfer of an electron and allows it to reversibly bind O2. Positively charged amino acid residues stabilize to negatively charged diatomic oxygen without an ionic bond. Hemoglobin unbound to oxygen is called deoxyhemoglobin and has a low affinity for oxygen. Once one oxygen molecule binds to the Fe, the proximal Histadine (figure 1) moves closer to the porphyrin ring because the Fe is now bound to six ligands instead of five. This disrupts the stabilizing ions that interact with Hb. The remaining Heme groups have an increased affinity for Oxygen. In addition to this positive cooperatively of binding, allosteric interactions regulate the binding and release of oxygen by Hb (Horton, 1996)."
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