Malaria, unlike many diseases, has evolved as a result of millions of years of interactions at various levels with the mammalian system and hence has found ways to gather resistance to drugs and insensitivity to other treatment modalities. Co-evolution and co-adaptation of the parasite, recrudescence, recurrence, drug resistance, and the complex pathophysiology of the infection process complicate treatment regimens, most of which are ineffective. This brings us to the conclusion that vaccination is the ultimate eradicative strategy. This paper's core idea is to give an extensive overview on the latest developments of anti-malarial vaccine technology.
Conjugated linoleic acids are a class of 18-carbon polyunsaturated fatty acids found primarily in the meat of ruminant animals and dairy products. Since being shown to inhibit skin neoplasia in mice by Ha, et. Al. (1987), CLA has been demonstrated to have antiatherosclerotic, antidiabetic, antiadipogenic, and anticarcinogenic effects in cell lines and animal models. Attention to these findings has led to the availability of CLA as a dietary supplement. The safety and efficacy of CLA in this capacity is not well established, however, since relatively few studies of CLA's effects have been conducted in humans.
The box_tree code is used to simulate the formation of 12-particle three-dimensional Yukawa dust clusters within a complex plasma. The structure of the cluster is analyzed; in particular, the potential energy is calculated for all clusters that fall into stable single-shell states and also for all clusters that fall into stable double-shell states. It is shown that the ground state may be either single-shell or double-shell, depending on the given Debye length. The dependence of cluster structure on Debye length is analyzed quantitatively.
Density functional calculations have been performed on a cyclohexadienol endoperoxide model system derived from the tyrosine model compound p-cresol and singlet molecular oxygen. Results indicate that the endoperoxide undergoes a 1,3 hydrogen migration to form a cyclohexadienone hydroperoxide.
Food-borne bacterial infections pose a significant risk for human populations. The increasing occurrence of antibiotic resistance in bacterial strains has heightened this risk further. This circumstance has led to a renewed interest in traditional treatments for infections. This investigation focused on the bio-protective properties of turmeric, which is a spice that is used in India for extensive medicinal and culinary purposes.
Triggerfishes (family Balistidae) are members of one of the most derived group of fishes, the Tetraodontiformes. Species of this family employ a median paired fin (MPF) swimming style that recruits the use of the dorsal and anal fins for propulsion. This study used ultra-thin slice plastination to investigate median fin myology of Rhinecanthus rectangulus, a common triggerfish within the Indo-Pacific region. This method maintained detail and accurate spatial relationships between anatomical features, allowing accurate rendering of the vertebral column, four sets of pterygiophores, one myotome, and two sets of muscle groups along the median fins.
Bacterial biodegradation is the basis for the bioremediation of contaminated sites. The key to its success is the use of bacterial strains with high metabolic activity for target contaminants. The goal of this project is to understand the bacterial biodegradation of dinitrotoluene (DNT) by a novel marine bacterium, Pseudoxanthomonas sp. JA40. Isolated along with forty other bacterial species from contaminated Johnston Atoll sand in 2003, JA40 is hypothesized to degrade DNT because it evolved in an environment deficient of organic nitrogen sources but rich in polycyclic aromatic hydrocarbons (PAH's) and polychlorinated biphenyls (PCB's).
Instrumental magnitude photometry of the eclipsing binary star DE CVn in the U color band was carried out using the Lowell Observatory 31-inch telescope with the NURO CCD photometer. Deep and flat primary minima with steep ingress and egress confirm the hypothesis that the primary component of this binary system is a hot white dwarf. New, more precise ephemeris of the system based on these and other observations is presented.
Dust particles in a protoplanetary disk coagulate into larger bodies which eventually form planetesimals. When the dust particles stick together, they form fluffy aggregates which often have a self similar structure characterized by the fractal dimension. The fractal aggregates can couple more closely to the gas in the nebula, which decreases their relative velocities. Since some of the gas particles are ionized, the dust becomes charged due to collisions with free ions and electrons. These dust properties, relative velocity and charge, have a large effect on both the coagulation rate and the fractal dimension.
We use interferometric maps to investigate the statistical properties of the velocity fields traced by H2O masers in five galactic regions of star formation. In a previous work, Strelnitski et al. (2002) concluded that H2O masing spots in such regions appear to probe highly intermittent supersonic turbulence and demonstrated that the two-point velocity correlation functions for the line-of-sight components of velocity traced by the masers could be approximated by power laws, with the exponents near the classical Kolmogorov value of 1/3 expected for high-Reynolds number incompressible turbulence.
The Pediatric Exclusivity Act of 1997 was enacted to implement an additional six months of patent protection for a drug. As a result, if a manufacturer conducts studies of the drug on children, the drug company will be able to benefit by having an effective monopoly of the drug for an additional six months. While the aim of this provision was to increase the safety of drugs in the pediatric population, the pharmaceutical industry has been accused of exploiting the law for financial gain. The charge is that drug manufacturers are only using the act to gain an extended patent for its large selling drugs in order to profit at greater margins.
Effective conservation strategies require that agencies account for genetic diversity and its geographic distribution within threatened species. Unionid mussels are among the most endangered taxa in North America, with between 55% and 72% of species having some protected status, and many others declining rapidly. With so few populations of these mussels safe from anthropogenic impacts, it is vital that we study relatively undisturbed species to understand historical genetic distributions.
Vibrio vulnificus, a common human pathogen, is autochthonous to warm estuarine and coastal waters where it can undergo different kinds of environmental stresses. Very little is known about how environmental isolates from Texas waters cope with extreme conditions; our objective was to study the response of these isolates under oxidative stress.
The lowly fixed-point recursion xn+1 = f(xn), which is at the bottom of the iterative methods evolutionary ladder, should come before the Newton-Raphson method. Yet in calculus texts the latter takes precedence, due probably to the appeal of its plausible geometrical interpretation visualized so convincingly as sliding down tangent lines. But relying on graphs and pictures can lead to simplistic thinking.
The debate regarding the effectiveness of current prostate cancer screening strategies and the necessity of population based testing is becoming a major issue within the medical community. While Prostate Specific Antigen (PSA) testing is the most widespread form of prostate cancer screening, its specificity of 63.1% and low sensitivity of 34.9% calls for a statistically improved and more effective method to more accurately and consistently detect the ninth most common form of cancer. New technology has enabled medical researchers to develop more reliable, less invasive screening methods.
This research asks what the relationship is between meanders of the Feher and Sebes-Körös Rivers and Early Copper Age Settlements located in Southeast Hungary. Done in conjunction with a National Science Foundation funded archaeological excavation of two Early Copper Age settlements, the purpose is to determine why almost all Early Copper Age settlements in the Great Hungarian Plain, where these excavations are located, are situated along river meanders.
The vertebrate limb is patterned by a number of interrelated molecular pathways which ultimately determine the musculoskeletal and soft tissue organisation of the completed limb. Once the limb field has been established, the proximodistal axis is primarily determined by fibroblast growth factors (Fgfs), dorsoventral by a Wnt system and anteroposterior by Sonic hedgehog (Shh). Although still relatively infrequent, congenital limb deformities may have profound physical and psychosocial effects on children and their families.
Localized surface plasmon resonance (LSPR), a collective electron density oscillation found exclusively in metallic nanostructures, is a phenomenon that is of practical significance. The strong UV-vis absorption band exhibited by metallic nanoparticles is a phenomenon not found in their bulk equivalent. Therefore, the LSPR response of metallic nanoparticles to changes in their surrounding dielectric environment may be exploited to use nanoparticle arrays as sensing platforms for biological or chemical sensors.
The Hawaiian Islands contain a variety of climatic regions, elevations and substrates, which are home to a large number of endemic flora and fauna. Unfortunately, these rare ecosystems and endemic species are facing a bleak future of endangerment and extinction, such as the Hawaiian lowland wet forest. Non-native and invasive plant and animal populations are currently out-competing and over-crowding native lowland species.
Archaeological surface survey is a useful, nondestructive tool for understanding the past. However, within various documents, archaeologists question the accuracy of surface artifacts to reflect the subsurface site. If surface materials mirror the site below ground, the patterns of surface artifact distribution would give archaeologists helpful insights. This project evaluated the uses, limitations, and results of archaeological site surface survey using survey data obtained from the Hungarian Copper Age site of Körösladány 14 during 2005.
Silver nanocubes 30-50 nm in diameter have been synthesized using a polyol process in which silver nitrate is reduced by ethylene glycol in the presence of a capping agent poly(vinylpyrrolidone) (PVP). A ligand exchange reaction was used to replace the PVP with another capping agent, allowing the nanocubes to be soluble in chloroform. Oleylamine, oleic acid, and decane-thiol were among the ligands investigated. The silver cubes were then used as sacrificial templates to generate hollow gold nanocages using a galvanic replacement reaction during which the silver cubes were titrated with chloroauric acid. The use of different capping agents allows us to further understand the role of the ligand in the galvanic replacement reaction.
Bacteriophage øX174 has been studied for many decades. Nonetheless, no one has ever developed a quantitative model of øX174 development. This model is important to justify the consistency of the literature data and for engineering purposes. Here, a quantitative model is developed for the intracellular øX174 proteins. By using ordinary differential equations, the change in the protein concentration is modeled as the difference between the protein synthesis and degradation rates.
Diseases such as retinitis pigmentosa and age-related macular degeneration lead to gradual loss of eyesight due to the progressive loss of retinal photoreceptors. Currently, several treatments for these diseases are being used to slow vision loss. One in particular hopes to restore partial vision by implanting an artificial retina using solar cells to provide electrical stimulation of the ganglion cells of the eye when exposed to light.
Body size (based on weaning weights) in mammals has shown varying importance for their reproductive and survival success. Therefore, size can be influential among an individual's interactions with the environment. This field study is the first to compare the body size of prairie voles (Microtus ochrogaster) and its effect on their interaction with others and overall survival while controlling the density of animals in each enclosure.
The overall goal of this project was to fabricate very sensitive microbridge Superconducting QUantum Interference Devices, SQUIDs, using electron beam lithography followed by metal deposition and lift-off. The smallest lateral dimensions in the SQUID devices are those of the Josephson junction, which is 20 nm x 20 nm. Two electron beam resists were stacked in a bi-layer in order to get both ultrahigh resolution and good lift-off.
Conventional Electron-beam lithography is done using a Scanning Electron Microscope (SEM), with a resolution limit of ~10 nm. However, there is continued need for higher resolution lithography. The goal of this project is to investigate higher resolution Electron-beam lithography using a Scanning Transmission Electron Microscope (STEM). In principle, the STEM has two main advantages: less scattering of incoming high energy electrons, and a smaller electron probe diameter. We have created 100nm wide trenches in PMMA resist, which are promising early results. Reducing the exposure of the resist will likely give higher resolution.
We have fabricated freestanding MnAs/GaAs nanowires using e-beam lithography and dry etching techniques. Nanowires as small as 75 nm in diameter were fabricated, with Magnetic Force Microscopy images of the nanowires showing the MnAs nanowire caps to be single-domain ferromagnets. The structures fabricated in this work hold promise for use in future studies of electrical spin transport.
Small dust grains consisting of aggregates of spherical monomers are seen with increasing frequency in fields such as dusty plasmas and observational astronomy. In many cases the only possible experimental data that can be collected from these aggregates is via the light they scatter or transmit, making it difficult to determine characteristics such as size and shape. This paper investigates a method for modeling the optical properties of aggregates created by computer simulated BCCA (Ballistic cluster-cluster aggregation) and BPCA (Ballistic particle-cluster aggregation).
Methyl tertiary-butyl ether (MTBE) is an oxygenate that allows the complete combustion of gasoline. Although it is not carcinogenic, there is rising concern about its effects on human health because of its high water solubility and some proven systemic toxicities in animals. MTBE has become a target for many bioremediation studies with some microbes already proven to be effective in bioremediating it. Recently we isolated a Bacillus amyloliquefaciens (BA) strain from pooled, MTBE-contaminated agar that can be used as a potential bioremediant microbe for MTBE.
The complete formation of nitrogenase is an essential part in understanding how the complex enzyme works and is essential for further manipulation and research of the structure. The exact formation process has yet to be determined, but it is hypothesized that models, containing gene deletions, derived using X-ray crystallographic analyses of nitrogenase structures, can provide snapshots of the formation process depending upon the deletion.
The research that will be presented in this paper concerns the synthesis and testing of a bimetallic homogenous catalytic system based on a tetraphosphine ligand system. The [Rh2H2(µ -CO)2(rac-et,ph-P4)]2+ homogeneous catalyst system discovered by G. G. Stanley's laboratory can be resolved into pure enantiomers and has been shown to be one of the best asymmetric hydroformylation catalysts for vinyl esters with 85% enantiomeric excess (ee) and 4:1 branched to linear regioselectivity for vinyl acetate (Stanley 2005).
Informal educational centers, such as museums and public aquaria, have looked towards interactivity as one way to make their exhibits more attractive and informative. In some institutions, such as aquaria, direct interaction with most of the specimens is impractical. However, touch-screen information systems may become an effective way to introduce interactive experiences to visitors.
By using principles of the creative design process, a series of low-level prototypes and user studies were created to inform the design of an information visualization technique that deals with the problem of visually representing information quality. Understanding and clearly representing information quality is an important step in overcoming the problems of "information overload", a term used to describe the problem of having stronger data collection than data processing techniques. The hypothesis was that illustrative rendering techniques would be an intuitive and effective means for the display of information quality in multidimensional datasets.
Dark energy, which is believed to be a cosmic energy density that is gravitationally repulsive and does not appear to cluster in galaxies, has been invoked to account for the recent measurement that the rate of the universe's expansion is accelerating. To better understand these phenomena, scientists utilize type Ia supernovae as calibrated candles. Lawrence Berkeley National Laboratory (LBNL) is developing the Supernova Acceleration Probe (SNAP), a space-based telescope that will be used to identify and measure supernovae.
Environmental scientists commonly study net air pollution levels, but rarely analyze the inorganic ionic composition of that pollution and the effect of weather conditions on that air pollution together. In order to determine the inorganic ion components of and weather condition effect on particulate matter with aerodynamic diameter less than 2.5 micrometers (PM2.5) in Claremont, California, we used a Particle-into-liquid-Sampler with Ion Chromatography (PILS-IC) system. This is the only study of its kind to employ the PILS-IC system in Claremont.
Imagine you are Rebecca. Or that she is your sister, your aunt, or your friend. Rebecca lives in a semi-urban town in South Africa - an illegal settlement made up of homemade shacks with limited access to clean water and toilets. At the age of 24, Rebecca is happy to be having a baby, since her partner wanted to start a family. She doesn't live with him yet, though he tells her he is saving to get a place for the two of them. He has been telling her this for 3 years. For now, Rebecca lives with her sister, who has her own shack that she shares with her daughter.
The new IS/LM establishes that monetary policies should not influence real economies in the long run since they cannot engineer a permanent departure of outout from its capacity level (King 2000). The purpose of this paper is to empirically evaluate limitations of monetary policies emphasized by the new IS/LM model. A long-run relationship between real interest rates and the real economy implies a possibility that monetary policies have permanent effects on the economy. Therefore, we tested four hypotheses in which interest rates and real economic variables might be related.
The functional properties of proteins depend on their three-dimensional shapes. Protein structures can be determined by X-ray crystallography as a tool. The three-dimensional structure of the apo form of the Escherichia coli L-arabinose isomerase (ECAI) has recently been determined. ECAI is responsible for the initial stage of L-arabinose catabolism, converting arabinose into ribulose in vivo. This enzyme also plays a crucial role in catalyzing the conversion of galactose into tagatose (low calorie natural sugar) in vitro.
According to Thomson Scientific, the company which determines the impact factor of scientific journals, the USA produced 2.9 million research papers during the period 1996-2006. Taiwan, the 13th country on this list produced 1.2 million scientific papers and you can imagine a large number contribution by other countries in between these two. These statistics mean that it is impossible for us to read all the research papers published in the field of our interest or expertise. Well conducted review articles helps readers to overcome this problem and keep updated and abreast with the current progress and the future direction of research in the area of their interest.
Hemophilias are genetic bleeding disorders for which there are still no cures. Treatment of hemophilias are difficult because patients need repeated infusion of missing coagulation factors, some patients develop inhibitors to the infused factors, and gene therapy is still not suitable for mass treatment. The choice between the two most common therapies, plasma-derived products or recombinant factor VIII or factor IX, is still a dilemma for clinicians involved in the care of patients with hemophilia.
The discovery and recognition of Archaea as the third domain of life on earth have led to exciting developments and characterization of a wide array of previously unknown microorganisms and associated components in the last few decades. Differences in composition and properties of major components such as cytoplasmic membranes, enzymes, and proteins of these extreme Archaea were found to play major roles in maintaining archaeal stability in seemingly inhospitable environments. Unique archaeal adaptations to drastically varying biosystems have aroused special interests in their respective potential in biotechnological applications.
Developing countries do not always have the resources in place to provide potable water for its population. This study investigates the current problem in Calcutta, India, and presents possible solutions. Half of the 202 people surveyed in this study were slum dwellers while the other half were apartment dwellers. A weighted average of the willingness to pay for potable water has been complied, analyzed, and compared to the cost of providing potable water. The willingness to pay exceeds the production and maintenance cost for the potable water supply scheme suggesting that a water tariff is economically justifiable. If a tariff is imposed, the operation and maintenance cost of the system could be covered by the service provided. The city would then qualify for further financing from the international banks to expand the surface water treatment plant and supply network system. This aid, in turn, would reduce dependence on ground water, which is environmentally unsustainable, because of natural arsenic contamination.
We present the results of the first study of statistical properties of velocity field and spatial distribution of the observed "hot spots" in methanol maser sources with available interferometric maps. Three Class I sources [DR21(OH), NGC6334IN, and L379] and one Class II source [W3(OH)] were investigated. In the majority of the sources, both the velocity difference between the pairs of spots and the average number density of the neighbors to a spot are adequately represented by a power law function of the spot separation.
Using interferometric maps, the statistical properties of the velocity fields traced by H2O masers in five galactic regions of star formation were investigated. In a previous work, Strelnitski et al. (2002) concluded that H2O masing spots in such regions appear to probe highly intermittent supersonic turbulence and demonstrated that the two-point velocity correlation functions for the line-of-sight components of velocity traced by the masers could be approximated by power laws, with the exponents near the classical Kolmogorov value of 1/3 expected for high-Reynolds number incompressible turbulence.
This study examines the ratios of animal species identified from faunal remains at two sites, Vésztő-Bikeri (V-20) and Körösladány-Bikeri (K-14), inhabited during the Early Copper Age (4500-4000 BCE) by people of the Tiszapolgár culture. The importance of this study lies in developing a greater understanding of the dramatic social changes that swept through this region during the transition from the Late Neolithic to the Early Copper Age. While there are a variety of possible explanations as to why these social changes have occurred, animal practices influenced by cultural choice may have had a significant effect on social reorganization in the Carpathian Basin.
Although it is one of the most common ailments on the planet, dental caries, more a complex interplay of factors, especially patient diet and the presence commonly known as cavities, remains a poorly understood disease. Caries are caused by of the bacteria Streptococcus mutans on the teeth. In spite of the fact that poor dental health has been linked to multiple full-body conditions and diseases, such as Multiple Sclerosis and Heart Disease, and that eighty percent of all American adolescents will be diagnosed with caries, there are still few successful preventative treatments. Rampant caries diseases are especially common among lower-income populations, such as the devastating pediatric disease Early Childhood Caries, which has reported rates of as high as ninety percent in some subpopulations. Recent research into the intricate microbial ecology of the mouth and the other risk factors that may play a role in caries formation has provided insight into new treatment and prevention possibilities for this extremely common infectious disease.
Parkinson's disease is characterized by the progressive death of dopaminergic neurons in the human brain. The misfolding and aggregation of α-synuclein, as well as the presence of reactive oxygen species, are thought to contribute to this cellular toxicity. The mechanism of interaction between these two pathways is unknown. Mitochondrial dysfunction, specifically, incomplete respiratory metabolism and loss of antioxidant enzymes, has long been implicated as the culprit for oxidant accumulation.