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Nitric Oxide (NO), 2005.
This paper explores whether nitric oxide is the same substance as an endothelium-derived relaxing factor, its use and its advantages and disadvantages.
64,020 words (approx. 256.1 pages), 130 sources, APA, $ 249.95
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Abstract
This paper explains that nitric oxide is an endothelium-derived relaxing factor, a neurotransmitter and an euro modulator present in the central and peripheral nervous systems. When generated in surplus, a likely toxic molecule forms part of the resistance against diseases. The author points out that the primary problem involved in the detection of NO result from its short span of life and a very low rate of concentration. Nonetheless, the paper demonstrates several quantitative modes for measuring NO and indicates their limitations. The paper stresses that the endothelium performs a vital role in the determination of blood pressure; primary endothelial irregularities, in addition to irregularities secondarily influencing the endothelium, are all possible suppliers to the advances of hypertension. Many charts and graphs.
Table of Contents
Introduction
Nitric Oxide: Advantages and Disadvantages
Is Nitric Oxide the Same Substance as Endothelium Derived Relaxing Factor
Nitric Oxide's Interactions with the Vascular Endothelium
Ways Nitric Oxide is Measured and the Problems Associated with Measuring
Conclusion
From the Paper
"The hydrogen peroxide has been projected to be a freely diffusible EDHF as agonist evoked relaxation in some arteries that are NO and autonomous prostanoid are inhibited by the enzyme catalyse that destroys this reactive oxygen species. Such findings have not been general and hence the role of hydrogen peroxide in EDHF responses is evoked by gap junction dependent and independent mechanisms. It is seen earlier that EDHF-type relaxations evoked by acetylcholine, ATP, substance P and cyclopiazonic acid depend on gap junctional communication. But the calcium ionophore A23187 irrespective of evoking EDHF-type relaxations was not vulnerable to gap junction inhibitors. Incubation with catalyse resulted in marked attenuation of A23187 induced EDHF-type relaxations but only inhibited reactions induced by high concentrations of acetylcholine. This indicated that EDHF-type relaxations induced A23187 may be arbitrated by hydrogen peroxide and would not associate with gap junctions."
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Chemical Symmetry, 2005.
An analysis of the importance of symmetry in inorganic chemistry
1,110 words (approx. 4.4 pages), 3 sources, MLA, $ 38.95
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Abstract
This paper examines how identifying the irreducible representation associated with a given bond, atom or sets, is of great value for three reasons. It looks at how it is a convenient way of labeling orbitals for reference, for determining which sets of atomic orbitals can combine with each other to form molecular orbitals and thirdly, for determining the number and nature of vibrational motions for a given molecule to give the most common applications.
From the Paper
"Improper rotation is a combination of rotation followed by reflection in the plane perpendicular to the axis of rotation. As with the other symmetry operations, the motion of the atoms is the operation. The symmetry element associated with improper rotation is an axis, which is the same axis as that used for the rotation part of the improper rotation. While there is a plane of reflection involved, it does not need to be specified for the improper rotation axis because it is always perpendicular to the rotation axis. Improper rotations are designated with the letter S. Reflection across the xy plane, which is perpendicular to the z axis doesn't move any of the atoms for this planar molecule."
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Radium, 2005.
A discussion about the origins and current uses of radium.
1,574 words (approx. 6.3 pages), 6 sources, MLA, $ 51.95
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Abstract
This paper briefly discusses the way that radium was discovered and first used. It explains how the awareness of the dangers of exposure were non-existent at the time and how many of the original workers with the substance died from poisoning. The paper looks at the precautions taken these days and how the use of the substance has developed.
From the Paper
"Radium, a pure metal, was discovered by the Polish chemist Marie Sklodowska Curie and her husband Peter, a French chemist, in 1898 from unrefined pitchblende, a material containing uranium (Gagnon 2004), or urarinite, in Joachimsthal, North Bohemia (Chemistry Operations 2003). Marie Curie observed that radium was more radioactive than uranium when they were separated. In 1911, she and Debiene isolated the pure metal through an amalgam of pure radium chloride, distilled in an atmosphere of hydrogen (Chemistry Operations). Seven tons of pitchblende yields 1 gram of radium. It belongs to the alkaline-earth family of metals that loses 1% of its activity only every 25 years. Lead is its final by-product in the long disintegration process (Chemical Operations). It is recommended that radium and minerals and materials containing radium should be exposed to the air to prevent radon from building up."
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MSG Bioprocessing, 2005.
A look at monosodium glutamate (MSG) and its uses.
1,768 words (approx. 7.1 pages), 8 sources, APA, $ 57.95
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Abstract
This paper examines MSG and its uses and takes a look at how it is made, including the fermentation process. The paper also discusses the technical details of the preparation process, the equipment commonly used, the use of enzymes and bacteria and examines the product packaging and quality control procedures. Finally, the paper includes a brief description of the market of MSG, and the socio-economic aspects of the product.
From the Paper
"Monosodium glutamate, or MSG, is the sodium salt of glutamic acid. Glutamate is an amino acid that occurs naturally in many foods known for their flavor, such as tomatoes and mushrooms. Additionally, glutamate is found as a naturally occurring amino acid in foods such as meat, fish, and many vegetables. It can also be found in foods such as ice cream, yogurt, soda, canned soups, flavored crackers, and chips. Glutamate is also produced in the human body naturally, helping to regulate the body's metabolic rate (WHO, 1988)."
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Pharmaceutical Licensing, 2004.
An analysis of compulsory licensing of pharmaceutical products.
4,300 words (approx. 17.2 pages), 12 sources, MLA, $ 113.95
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Abstract
This paper highlights the causes and effects of the compulsory licensing of pharmaceutical products. The paper discusses the fundamental positions, attitude, inclination, and concerns of the developed world and the under-developed world with regard to the intellectual property rights of the pharmaceutical products. The paper also concentrates on the subject of the intellectual property rights of the biotechnology products. The paper also exposes the priorities of both the developed world and the under-developed world, priorities that have been a major hurdle in all previous negotiations on Intellectual Property Rights (IPR) protection. Subsequently, the paper gives practical recommendations that ought to be followed in all future negotiations so that both parties can derive maximum benefits from the patentability of pharmaceutical products.
From the Paper
"Over the years, it has become a general belief that biodiversity will pave the way for a solution to almost all the diseases that exist today and continue to negatively influence our lives. This belief has led scientists to take further steps in the Research and development (R&D) of biotechnology. These steps comprise of various compounds, compounds that are biologically active, compounds that are natural resources, for example microbes, insects, fungi, marine organisms, and plants. However, laboratories are not capable of producing these complex biologically active and complex compounds. This is because the key places of genetic biodiversity are situated in the tropical and the subtropical regions of the world (Tara, 1994). Therefore, it is imperative for biotech scientists to go into the tropical forests with the purpose of locating these biologically active compounds."
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G Protein-Linked Receptors, 2004.
An analysis of G protein-linked receptors in communication between cells.
3,973 words (approx. 15.9 pages), 16 sources, MLA, $ 107.95
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Abstract
This paper analyzes the fundamentals of the large and complex body of information already collected and still in progress on the subject of G protein-linked receptors. The paper highlights the basic nature of G protein-linked signaling and explains how physiological regulation occurs through particular mechanisms.
From the Paper
"Cells in multi-cellular organisms, like animals, need to communicate among themselves in directing and regulating growth, development and organization (Altruis Biomedical Network 2003). Such communication modes include secreting chemicals that signal to distant cells, display cell surface chemicals that influence other cells in direct physical contact, and directly through porous cellular points called gap junctions (Altruis Biomedical Network). Endocrine signaling demonstrates the first mode, wherein hormones are secreted in the bloodstream to distant target cells. Paracrine signaling illustrates the second mode, wherein local chemical mediators are secreted and act only on cells in the proximate environment. And synaptic signaling exhibits the third mode, wherein molecules are released by vesicles at those junctions called synapses. The molecules are neurotransmitters that spread out and act only on the postsynaptic target cell (Altruis Biomedical Network). Protein receptor molecules that are on or within the target cells bind to the hormone, paracrine or neurotransmitter and a response results, depending on the speed and selectivity of the delivered signal."
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Women and Science, 2004.
A discussion about the acceptance of women in the field of science.
754 words (approx. 3.0 pages), 2 sources, MLA, $ 26.95
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Abstract
This paper examines the fact that issues of gender continue to strongly influence both scientific literature and the practice of science today. Based on notions of gender that developed during the enlightenment and the Victorian era, the paper explores science's long history of incorporating gender norms and sex dichotomies into science.
From the Paper
"Notions of gender have influenced the historic development of science in the west, as reason and science have long been seen as male traits. Similarly, gender ideals such as the characterization of females as maternal, associated with nature, irrational, and week have been reflected in scientific literature. Today, science continues to be influenced by ideas of gender, as literature reflects gender biases, and female scientists routinely must challenge gender biases."
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Entropy, 2004.
An analysis of entropy, the spontaneous dispersal of energy.
1,000 words (approx. 4.0 pages), 4 sources, MLA, $ 35.95
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Abstract
This paper discusses the concept of entropy, describing how it governs every physical, chemical, and biological aspect of life. The paper explores two different perspectives to view entropy: that it is essentially dispersive in nature and that it is constructive in nature. The paper provides examples to illustrate entropy.
From the Paper
"Entropy effects are seen in almost every instance of life. At an atomic and molecular level, the energy of substances is associated with their motion. A more energetic compound has greater motion. This atomic and molecular motion can be translational, vibrational and/or rotational, in decreasing order of energy. Each of these motions is associated with energy levels that are discrete. Atoms and, in turn, molecules cannot have randomly assigned energies. This means that substances can possess only discrete quanta or packets of energy."
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Lactose, 2004.
This paper discusses lactose, one of the major components of milk.
805 words (approx. 3.2 pages), 5 sources, APA, $ 28.95
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Abstract
This paper relates that lactose, an important and well-understood component of milk, provides an important source of nutrition during development, and, for individuals without lactose intolerance, milk often continues to be an important part of a healthy and varied adult diet. The author points out that lactose intolerance is a common issue for much of the world's population, especially people of Asian and non-Western European decent, but a large number of Europeans can easily digest lactose. The paper relates that, in the Western society, lactose (within milk) is used within a wide variety of milk products, such as cheeses, cottage cheese, sour cream, and yogurts; in addition, milk is used in a wide variety of other food products, including breads, pizzas, ice cream products, and even cereals.
From the Paper
"In structure, lactose is a white crystalline disaccharide that is comprised of two sugars that are bound together: glucose and galactose. Glucose and galactose are monosaccharides. Lactose has the same chemical formula as sucrose and maltose (C12H22O11). However, lactose differs from sucrose and maltose in structure. When hydrolyzed, lactose yields D-glucose and D-galactose. This hydrolysis is catalyzed by lactase within the digestive tract (Miller). Thy hydrolysis of lactose results in increased sweetness and a depression of the freezing point of milk."
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A Brief History of Kevlar Development, 2004.
Describes Kevlar, a material best known for its use in bulletproof vests, and its many applications.
3,025 words (approx. 12.1 pages), 16 sources, APA, $ 88.95
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Abstract
This paper provides an overview and background of aramids, in general, and Kevlar, in particular, including its physical properties, its advantages and disadvantages, as well as anticipated future developments and trends in its production. A summary of the research is provided in the conclusion.
Introduction
Review and Discussion
Advantages and Disadvantages
Future Developments and Trends
Conclusion
From the Paper
"Background and Overview. Kevlar is an industrial textile that is most commonly known in the manufacture of bulletproof vests; however, it is also used in the manufacture of composites, and fiber optic and electromechanical cables (Seewald, 1991). Industrial textiles refer to the manufacture of such fabrics as asbestos, glass fibers, carbon fibers and Kevlar, which are produced for the automotive, aerospace sectors of industry (Martin, Penn & Scattergood, 1991). Following the success of nylons in such applications, aromatic nylons known as aramids were created through the condensation of a diamine and terephthalic acid (this is a carboxylic acid that contains a hexagonal benzene ring in its molecules). The close packing of the aromatic polymer chains resulted in a strong, tough, stiff, high-melting fiber that was suitable for use in radial tires, heat- or flame-resistant fabrics, bulletproof clothing, and fiber-reinforced composite materials. DuPont first began to produce Nomex (its trademark for poly-meta-phenylene isophthalamide) in 1961 and Kevlar (the trademarked name of poly-para-phenylene terephthalamide) in 1971 (Stevens & Kauffman, 2004)."
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