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The Atoms in My Hand, 2002.
An insight into atoms - what they are and where they come from.
715 words (approx. 2.9 pages), 3 sources, MLA, AU$ 41.95
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Abstract
The paper gives a brief insight into atoms from the beginning of recognition of their existence by the ancient Greeks, to the ability today to create man-made ones. It discusses the chemical composition of atoms and how scientists can now predict their behavior with great accuracy.
From the Paper
"According to existing theories and experimental results, the Big Bang took place about 12,000-15,000 million years ago. Within the first three minutes of the existence of the Universe, the light elements originated. Atoms came along after about 300,000 years and the stars and galaxies originated during the first million years. However, it took a while for humans to recognize atoms, although they were right before their eyes."
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Acid Rain, 2002.
A discussion of the concept of acid rain and its environmental dangers.
945 words (approx. 3.8 pages), 3 sources, MLA, AU$ 54.95
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Abstract
This paper provides a definition of "acid rain" and how it is formed. It looks at the dangers of acid rain and the damage it is doing to the environment. It briefly examines options and programs that can be performed to reduce acid rain.
From the Paper
"The term ?acid rain? is a little misleading. Rain is naturally acidic, from both carbon dioxide in the air and absorption of chlorine from the ocean (Gordon, 2002). All compounds can be measured for acidity or alkalinity on a Ph scale ranging from 0 ? 14, with anything below 7 showing at least slight acidity. Rain is judged ?acid? when its Ph falls below 5. (Gordon, 2002) Environmental scientists are concerned because in some parts of our country, the level of acidity in rain and snow has increased beyond its normal levels. This has had a serious impact in several areas, including our forests in the northeast and many of our most valued monuments."
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Medicinal and Recreational Purposes of Drugs, 2002.
A study of alcohol, marijuana, cocaine, morphine and heroin, outlining their medicinal and recreational purposes.
2,353 words (approx. 9.4 pages), 16 sources, APA, AU$ 117.95
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Abstract
This paper discusses five drugs (alcohol, marijuana, cocaine, morphine and heroin) commonly used for recreation and examines their medical effects. The writer describes each drug, its legal status and illustrates its uses as medical agents. The paper explains that the complex interaction of social acceptance, proven benefits as a medical agent, and potential side effects (including addiction) all played an important role in determining if a specific drug is used as a medical agent in today?s health care system.
From the Paper
"Alcohol, marijuana, cocaine, morphine and heroin have all been used extensively as medical agents. All five drugs have also been used extensively for recreational purposes. As a result of their known adverse effects, marijuana, cocaine, morphine and heroin were all made illegal. However, alcohol remains legal. There is a resurgence of interest in the medical effects of marijuana, cocaine and morphine."
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Dry?Cell Batteries, 2002.
A technical research report on the definition of dry-cell batteries and their kinetic make-up.
835 words (approx. 3.3 pages), 2 sources, APA, AU$ 47.95
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Abstract
The paper discusses dry-cell batteries which were invented as an alternative to higher leaking, long lasting batteries. Today?s advanced electronics are demanding more battery power and it is not unusual for a highly developed electronic item to go through two or three sets of batteries in a day. The paper shows that as technology advances, the stronger the battery demand and this brought about the invention of the dry-cell battery. The purpose of this technical research is to define dry cell batteries, their kinetic make-up, and how are they recycled.
From the Paper
"Recycling batteries saves the environment and ensures proper disposal. There are many programs which assist in helping individuals learns how to recycle batteries. There is one program called ?Charge Up To Recycle? which educates people on the recycling process, and the companies that recycle batteries. The objective of this program is to make everyone aware of the available services and encourage them to participate in recycling of the batteries. There are some battery recycle facilities that charge a small fee for used up batteries, but most of these facilities will take the batteries free of charge. The purpose of the battery manufacturers is to get everyone involved in recycling old batteries. Recycling batteries can be very beneficial to the air, eliminating lots of air pollution."
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Polymers, 2002.
A look at the uses of polymers and biological macromolecules.
1,810 words (approx. 7.2 pages), 19 sources, MLA, AU$ 94.95
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Abstract
An examination of the Van der Waal equation of state in a Virial expansion and a look at how Polymers are being used today in every walk of life. This paper shows how polymers are well-defined aggregates of very simple organic molecules. It defines these matters and looks at their uses in biochemistry.
From the Paper
"From thermodynamics and the kinetic theory of gases, the Pressure of an ideal gas is described as sum of the transfer of collision energy of gas molecules on the walls of the container. The inter-atomic interactions depend upon the density of the system. Inter-particle interactions, primarily attractive forces, reduce the overall pressure of the system. This interaction is called internal pressure. By rewriting the Van der Waal equation of state in a Virial expansion, we obtain an equation for Pressure p: (Atkins, 1987)
p = RT/(Vm ? b) - a/Vm2
a/Vm2 is the internal pressure of the gas; a and b are constants for each gas and Vm is the molar volume of the gas, R is the Gas Constant."
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Boron Composite Structures in Aviation, 2001.
This paper studies the past and future use of boron composite structures in aviation.
1,190 words (approx. 4.8 pages), 11 sources, APA, AU$ 65.95
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Abstract
This paper details a brief history of boron composites from its earliest applications to recent developments. It studies the application of boron in composite epoxies and fibers and the use of these materials in airframe manufacturing. It includes figures showing usage of Boron composite. It concludes that boron has been very successful in aircraft manufacturing if the costs can be brought down.
From the Paper
"Compounds of boron, most notably from unfinished borax ore, known as Tincal, were exported from Tibet in olden times. Historically, boron has been used for refining gold and silver in Arabia, ceramic glazes in China, and embalming in Egypt.
"Boric acid, a mild antiseptic, was isolated in the laboratory by chemistry professor William Homberg in 1720. Sir Humphrey Davy, a British chemist, and two French chemists, Joseph Gay-Lussac and Baron Louis Th?nard, discovered the element, boron, in 1808 concurrently. However, it took another 155 years before science turned its focus from borax to boron, and began to reveal the secrets of this mysterious and valuable element."
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Naloxone and Heroin Addiction, 2006.
This paper discusses the use of naloxone to treat heroin overdose and heroin addiction.
2,414 words (approx. 9.7 pages), 13 sources, APA, AU$ 119.95
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Abstract
In this article, the writer notes that heroin use is a problem plaguing countries all over the world. One of the most common and successful ways to combat heroin use is with pharmacological measures. The writer points out that naloxone, a narcotic antagonist, is used to reverse the effects of a heroin overdose. In 2002 it was approved in a combination tablet with buprenorphine for the treatment of heroin addiction. The writer discusses that the approval of the combination buprenorphine/naloxone tablet means that more nurses working in an outpatient setting will be administering naloxone to patients seeking help for heroin and opiate abuse. The writer them emphasizes the importance of explaining the indications and possible side effects of any drugs administered to patients, and to know the proper procedures to take should a patient misuse the medication. The writer concludes that hopefully, as the medical community becomes more aware of the problems associated with drug use and dependence, we will be able to come up with better solutions to solving the problem.
From the Paper
"In a study done by Cantwell et al., paramedics assessed patients for respiratory status, concurrent drug intoxication, and evaluated the patient according to the Glasgow Coma Scale. Overdose victims were more likely to receive less than the standard dose of naloxone with each single increase in number of breaths. With an increasing Glasgow Coma Scale score, patients were more likely to receive less than the standard dose of naloxone. Patients with concurrent alcohol intoxication were more likely to receive greater than the standard dose of naloxone. It is thought that alcohol combined with heroin causes greater CNS depression than that produced by heroin alone. The trend towards older patients, and male patients receiving higher doses was also seen. The study suggests that patients with a higher level of consciousness and respiratory rate require a smaller dose of naloxone to return to a normal state than those patients with a lower respiratory rate and decreased level of consciousness."
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Coliphages, 2007.
Looks at an experiment to isolate coliphages from sewage.
1,570 words (approx. 6.3 pages), 9 sources, APA, AU$ 83.95
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Abstract
This paper explains that virtually all bacteria strains have viruses specific to them. The paper then describes an experiment that takes coliphages from sewage and, after enrichment and filtration processes, exposes the E.Coli R10 strain to the phages to obtain the phage specific to the strain. The paper further explains that the bacteria strains are grown on agar plates in the presence of coliphages, and strains W3104-A on plates K12 and W3104 and R12-B on plate K12 developed resistance. The paper then reports that the W3104-A strain is further tested and retains its resistance.
Table of Contents:
Abstract
Introduction
Materials and Method
Isolation and Enrichment of Coliphage from Raw Sewage
Filtration of Coliphage Mixtures
Dilution and Plaque Preparation of R10A and R10B E. Coli Strains
Mutation and Isolation of Phage-Resistant E. Coli Strains
Sensitivity of Phage-Resistant Mutants to Bacteriophages
Results
Discussion
Table: Colonies of Bacterial Strains Response to Coliphages
From the Paper
"Bacteria have the ability to develop resistance to viruses [6], so as it can be expected some strains (namely W3104-A and R12-B) developed phage-resistant colonies. It is known that certain genetic elements called "episomes" are instrumental in creating phage-resistance in E. Coli strains such as K12 [8]. As indicated in table 1, there were numerous contaminations; this was certainly due to many of the unfiltered cultures that were used. This was done because of time constraints and shortage or missing supplies in the lab."
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Homeostasis, 2008.
A detailed presentation of homeostasis, a dynamic process in the human body that balances fluids and electrolytes.
3,295 words (approx. 13.2 pages), 5 sources, MLA, AU$ 153.95
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Abstract
This paper explains that disorders of homeostasis, fluid, and electrolyte balance occur in every setting, with every disorder, and with a variety of changes that affect healthy people. The paper also describes body fluids and electrolytes and the process of regulation of body fluid through osmosis. In addition, the paper discusses issues of homeostasis in the kidneys, skin, lungs, and the gastrointestinal tract.
Table of Contents:
Introduction
Body Fluids
Electrolytes
Regulation of Body Fluid Through Osmosis
Diffusion
Diffusion
Filtration
Sodium-Potassium Pump
Electrolyte Balance
Kidneys
Skin
Lungs
Gastrointestinal Tract
Laboratory Tests for Evaluating Fluid Status:
Osmolality
Osmolarity
Homeostatic Mechanisms
Kidney Functions
Heart and Blood Vessel Functions
Lung Functions
Pituitary Functions
Adrenal Functions
Parathyroid Functions
Baroreceptors
Renin-Angiotensin-Aldosterone System
Antidiuretic Hormone and Thirst
Osmoreceptors
From the Paper
"The hypothalamus manufactures ADH, which is stored in the posterior pituitary gland and released as needed. ADH is sometimes called the water-conserving hormone because it causes the body to retain water. Functions of ADH include maintaining the osmotic pressure of the cells by controlling the retention or excretion of water by the kidneys and by regulating blood volume.
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The Effects of Chemicals on Daphnia Heart, 2005.
Describes an experiment that looks at the effects of chemicals on heart of a Daphnia.
815 words (approx. 3.3 pages), 1 source, MLA, AU$ 47.95
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Abstract
This paper describes an experiment, which stimulates the hearts of Daphnia by using caffeine, nicotine, epinephrine, ethyl, a diluted salt solution and various pH 10 solutions. The author reports measuring the heart rates of the Daphnia and discusses the changes in heart rate for each of the stimuli.
Table of Contents:
Materials and Methods
Result Analysis
Discussion
Graphs
From the Paper
"Giving Nicotine to the second Daphnia, caused a drop in its heart rate (graph 2). Since nicotine is a widely used drug which is a depressant, it lowers the beating of the Daphnia heart. The Daphnia that acquired epinephrine, experienced a jump in heart rate (graph 3). Epinephrine, otherwise know as adrenaline, is secreted by the adrenal medulla in response to stress. It stimulates autonomic nerve action, which is why a rise is heart rate was observed."
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Ginseng and Macrophage Cells, 2008.
A look at the immune stimulating properties of ginseng on macrophage U937 cells.
1,472 words (approx. 5.9 pages), 16 sources, MLA, AU$ 78.95
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Abstract
Ginseng has been used for medicinal proposes for thousands of years. It seems to improve health, and boost individuals' immune systems. This paper describes an experiment to scientifically determine that ginseng is indeed beneficial for the immune system. The paper relates that, by exposing macrophage U937 cells to varying concentrations of ginseng alongside ethanol, it was determined that the cells in presence of ginseng show an increase in cell concentrations, and in nitric oxide production.
Outline
Introduction
Materials and Method
Results
Discussion
From the Paper
"It is well known that most of the medicines in the world are derived from plants. For many years plants have been investigated in an effort to help boost the human immune system, and accelerate the recovery process from infectious diseases. Panax ginseng is a notable traditional herbal medicine that has been utilized by the Chinese for thousands of years [1]. Although there have not been extensive studies of ginseng's benefits to the immune system [3], the plant's capacity on the function of leukocytes has been under study [3]. The use of ginseng as a medicine has been gaining popularity in the west [4], much of this is because of studies that have linked it to prevention of cancer [5]. It is believe that much of the beneficiary components of ginseng are because of ginsenosides, a various group of steroidal saponins, which are able to target and affect a large number of tissues [4]."
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Yeast and Fermentation, 2007.
This paper examines the growth and contamination of yeast used as a fermenting agent in varying environments.
1,312 words (approx. 5.2 pages), 3 sources, MLA, AU$ 72.95
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Abstract
The paper discusses an experiment that examines how yeasts adapt to various competitions and how they fare against several changes in their surrounding environment. The paper explains that this experiment will determine the factors that affect the growth of yeast positively and negatively. The paper includes tables and graphs with the results of this experiment.
Outline:
Introduction
Results
Discussion
From the Paper
"Yeast is an excellent system in biology as it is a eukaryote whose genome can easily be influenced and controlled. Yeast also share similarities with their competitive prokaryotic counterparts, bacteria, such as fast growth, and wide dispersal of their cells. A species of yeast, more specifically Saccharomyces cereviseae was the first eukaryote whose genome was fully sequenced (Goffeau et al., 1996). The S. cereviseae is also a commonly used yeast in the fermentation of various products such as beer, by the break down of complex organic substances like glucose, into the simpler alcohol. Therefore it is only natural that people have been so interested in yeast and its invaluable properties in fermentation. Much ongoing research exists that tries to exploit the process of brewing for fast fermentation and maturation in producing malt beverages using yeasts (Masschelein C.A. et al., 1994)."
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Isolation and Purification of Muscle Proteins, 2008.
This paper discusses the isolation and purification of actin and myosin in skeletal myofibrils.
1,791 words (approx. 7.2 pages), 7 sources, APA, AU$ 93.95
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Abstract
The writer explains that in the set of experiments discussed in the paper, myosin and actomyosin were isolated and gradually purified from rabbit muscle myofibrils. The two proteins were initially precipitated together out of solution, in order to remove any impurities. Then, the two proteins could be separated from each other, by taking advantage of differential solubility. The writer notes that after each time they were re-suspended or redissolved, the solutions were centrifuged in order to further improve purity. Any solution containing the contractile proteins or ATP were kept on ice during the experiments, and stored in a freezer at all other times. The writer discusses that using the Bradford protein assay and the SDS-PAGE, the concentrations and weights of the purified proteins in the final solutions were measured. For all protein samples, no appreciable concentration of protein could be detected after diluting the samples by 100 times. However, the other two dilutions yielded normal results.
Outline:
Abstract
Introduction
Materials and Methods
Results
Discussion
From the Paper
"The head of the myosin is the part which interacts with the other molecules. Without ATP, the myosin head is bound tightly to the actin, called the rigor state. However, ATP weakens this interaction by opening a cleft in the myosin head and disrupting the actin-binding site. When the myosin head is free of actin, it hydrolyzes ATP to ADP. This causes a conformational change in the head that moves it to a new position, closer to the (+) end of the actin filament, (away from the origin site) where it reattaches. The dissociation of the phosphate from ATP also causes a conformational change, this time in the myosin head. As a result, myosin returns to its original state (the rigor state). Because myosin is still bound to actin, this conformational change exerts a force that causes myosin to move the actin filament. This is the power stroke. Essentially, contraction is a series of these power strokes by the actomyosin complex, the myosin head is moving along the actin filament through constant detachment and reattachment."
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Measuring Speeds, 2006.
This paper examines mobile eukaryotic cells.
1,063 words (approx. 4.3 pages), 5 sources, APA, AU$ 60.95
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Abstract
The writer notes that the objective of the laboratory describe in the paper is to observe mobile cells and their characteristics. Three distinct samples are viewed: plant cells from an Elodea leaf, a eukaryotic animal cell called Tetrahymena pyriformis, and myofibrils from a rabbit muscle. The writer points out that when movement is detected in the plant and animal cells, it can lead to calculations of speed. Both intracellular and inter-cellular movement is exemplified in the samples. The writer notes that cells are not only observed under natural conditions, but also after biochemical alterations. The effects of these biochemical changes are also noted. The addition of methyl cellulose enables more accurate observation of the animal cells, since it reduces their speed. The writer concludes that when the ATP was added, the decrease in size proved that the myofibrils are responsible for the muscular function and that the muscle is dependant on the myofibrils successfully working together. However, each cluster of myofibrils appeared to be structurally independent, meaning it was not connected to any other cluster.
Outline:
Introduction
Materials and Methods
Discussion
References
From the Paper
"The Tetrahymena cells were all similar in size, and were either circular or elliptical in shape. Their nuclei and cytoplasms were clearly seen, but any other organelles were difficult to distinguish. Whether they moved horizontally, vertically or diagonally, linear motion was consistent in all the cells. It also seemed like they each one followed a unique path across the field of view. After adding methyl cellulose to these cells, their movement became significantly slower, and deceleration continued until the cells stopped moving altogether. However, their movement also became random, sporadic and generally unpredictable, since they did not seem to be following any particular path. As well, some cells began moving in a circular motion, as if around an axis, and many cells began to gather in large groups once they stopped moving."
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Isolation and Purification of Lysozyme, 2007.
This paper looks at an experiment in an enzyme purification lab for the purification of lysozyme.
2,117 words (approx. 8.5 pages), 5 sources, APA, AU$ 107.95
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Abstract
The writer explains that in this experiment, lysozyme was purified from egg white solution into 24 fractions using gel column chromatography. The writer points out that the odd-numbered fractions were then assayed in order to determine the enzymatic activity of lysozyme, while the even-numbered fractions were assayed for total protein content, using the Bradford protein assay procedure. The writer notes that lysozyme is one of the most well-known enzymes, being abundant in mucus, tears, and albumen (commonly known as egg white).
The writer concludes that the purification of lysozyme from egg white was only somewhat successful since the estimated value of the molecular weight, 14.25 kDa, is practically the same as the known weight of 14.3 kDa. However, the specific activity, calculated at 400 units/mg, was significantly less than the expected specific activity of 25 000 units/mg of protein.
Outline:
Abstract
Introduction
Materials and Methods
Results
Calculations
Discussion
Conclusion
From the Paper
"Lysozyme is itself composed of 129 amino acids, including four disulfide bridges and three sets of alpha helices. The enzyme's active site consists of a long groove that can hold as many as six polysaccharides. According to past experiments, specific activity of lysozyme from egg white is approximately 25 000 units/mg. This is the expected result for this experiment. However, one factor that influences the specific activity is the actual column and type of chromatography being used, since accuracy differs among the different types of chromatographies. Therefore, some are able to purify enzymes better than others, giving a more accurate specific activity. In addition to obtaining the specific activity, molecular weight of the enzyme can be determined by comparing the fraction in which most of the enzyme eluted with the fractionation range."
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A Chemical Investigation of Fragrances, 2007.
A discussion of the discovery and development of fragrances, focusing on their chemical make-up and manufacturing process.
1,664 words (approx. 6.7 pages), 13 sources, MLA, AU$ 88.95
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Abstract
This paper looks into the chemical make-up manufacturing processes of fragrances. It begins by discussing the history of fragrances and their uses. It specifically discusses the discovery and development of fragrances. The paper also looks briefly at the shortcomings of fragrances that may pose health risks and other problems.
Table of Contents:
Introduction
Chemistry
Manufacturing Process
Insights
Summary-Conclusions
Appendix
From the Paper
"Many substantive (long-lasting) odorants are known, but a great number of them are too volatile to be perceived more than a few hours after their application. This is the reason why more efficient and effective fragrance-delivery systems, especially for laundry-care products, are intensely sought. The use of "prodrugs", an inactive drug derivative that is converted in the body into its active form, is a well-established technology to improve the oral bioavailability or the penetration across biological membranes. This led to the development of a wide range of precursors that are cleaved by hydrolysis during the laundry process to generate in situ fragrance materials, for example, aldehydes and ketones derived from oxazolidines and ionones and damascones from sz-amino compounds have been developed by Procter & Gamble Fragrance chemists are still looking for new systems with improved stability and release properties."
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