Physical optics for oven-plate scattering prediction

An oven assembly design is described, which will be used to determine the effects of temperature on the electrical properties of materials which are used as coatings for metal plates. Experimentally, these plates will be heated to a very high temperature in the oven assembly, and measured using a microwave reflectance measurement system developed for the NASA Lewis Research Center, Near-Field Facility. One unknown in this measurement is the effect that the oven assembly will have on the reflectance properties of the plate. Since the oven will be much larger than the plate, the effect could potentially be significant as the size of the plate becomes smaller. Therefore, it is necessary to predict the effect of the oven on the measurement of the plate. A method for predicting the oven effect is described, and the theoretical oven effect is compared to experimental results of the oven material. The computer code which is used to predict the oven effect is also described

A plant-made cholera toxin B subunit enhances mucosal wound healing and protects against ulcerative colitis and colon cancer.

This dissertation describes the previously unidentified effects of a plant-produced recombinant cholera toxin B subunit (CTBp) on the gastrointestinal (GI) tract and its ability to protect against inflammation in a mouse model of colonic injury and ulcerative colitis (UC). To comprehensively analyze CTBp’s impacts on the GI tract, we employed global analysis methodologies based on multi-color flow cytometry to analyze immune cell populations in GI and systemic lymphatic compartments, gene expression microarray to decipher transcript-level changes in the colon and small intestine, and 16S rRNA sequencing to characterize fecal microbiota. Based on a drastic shift observed in the immune cell profile and gene expression pattern in the distal colon, we built a new working hypothesis that CTBp may enhance mucosal protection in the colon. To address this hypothesis, we used the Caco-2 human colonic cell line and the mouse dextran sulfate sodium (DSS) colitis model. After demonstrating the potential of CTBp as a mucosal healing and anti-colitic agent, the dissertation will be summarized and future directions discussed

Acetaldehyde dehydrogenase 2 (ALDH2) activation protects hepatocytes from mitochondrial damage and death caused by 4-hydroxynonenal.

Alcoholic liver disease (ALD) ranks among the major causes of morbidity and mortality in the world and effects millions of patients each year. Progression of ALD is well characterized and is actually a spectrum of liver diseases, which progresses from steatosis, to inflammation and necrosis, to finally fibrosis and cirrhosis. However, the underlying mechanism(s) of ALD are not as well understood, and as a result there is no FDA-approved therapy to prevent or reverse the disease. With a better understanding of the mechanism(s) and risk factors that mediate the initiation and progression of ALD, a targeted therapy can be developed to treat or prevent it. The regenerative capacity of the liver is inhibited in fibrosis and cirrhosis. By enhancing the regenerative ability of the liver we may be able to reverse the effects of ALD. Indeed, recent in vivo studies by this group indicate that activating Aldehyde Dehydrogenase 2 (ALDH2) with Alda-1 (a novel ALDH2 activator) or Ethanol (EtOH) protects against oxidative stress and damage to the liver, as result enhancing regeneration. Because ALDH2 can protect mitochondria from oxidative stress that results from partial hepatectomy, oxidative stress from other sources should be protected against as well. To test this hypothesis, primary hepatocytes were isolated from mice and plated on 96-well plates for analysis via Cellomics High Content Screening. Some mice were administered EtOH for 3 days prior to hepatocyte isolation or exposed to Alda-1 to activate ALDH2. Cells were exposed to 4-Hydroxynonenal (4-HNE; 0-1000 µM) for 0-24 H. Activation of ALDH2, by pretreatment with EtOH or Alda-1 preexposure, clearly protected isolated hepatocytes from 4-HNE toxicity. Mitochondrial membrane potential was significantly increased in cells with activated ALDH2 and membrane permeability was decreased in these cells as well. These changes in hepatocyte viability indicate that activation of ALDH2 protects cells from oxidative stress

A Study of Selected Chemical and Biological Conditions of the Lower Trinity River and the Upper Trinity Bay

Concern over the effects of water development projects on coastal nurseries prompted the Department of Wildlife Science of Texas A&M University, with the cooperation of the UO So Bureau of Commercial Fisheries, Galveston, to undertake a study of a threatened nursery in the Galveston Bay System. A long-range program for the development of the Trinity River Drainage Basin includes the construction of several multi-purpose reservoirs along the main river (Fickessen, 1965). Of immediate threat to Galveston Bay nurseries was the reservoir to be constructed at Wallisville, Texas (Trinity River Mile 3.9)0 The site is close to Trinity Bay and the dam will traverse the relatively wide deltaic region of the Trinity River (Figure 2). The completed dam will serve as an effective barrier to salt water. Approximately 12,500 acres of marsh behind the dam will be come a freshwater conservation pool. The marsh area below the dam (8,200 acres) will also be modified through changes in the freshwater flow. It is assumed that tile Wallisville Dam will be completed and that many of the conditions described here for the study area will be drastically changed. The aim of this study was to gather data which would establish file role of the threatened marsh as a nursery for important marine and estuarine species It is recognized that these data will serve in planning and evaluating future water projects of this nature. Data reported here cover the period from March, 1966, through May, 1968. The study was limited to commercially important species with special emphasis given to the shrimps. The Bureau of Commercial Fisheries had maintained collecting stations in trinity Bay and made several preliminary investigations in the area of the proposed Wallisville Reservoir, but the actual extent to which commercially important species were utilizing these threatened wetlands was unknown. This paper attempts to demonstrate the extent to which the marsh has been utilized by the white shrimp (Penaeus setiferus Linnaeus), the brown shrimp (Penaeus aztecus Ives), the blue crab (Callinectes sapidus Rathburl), and the Gulf menhaden (Brevoortia patronus Goode). Some of the information presented here may be pertinent to an understanding of the same species in other low salinity environments

The SQM/COSMO filter: reliable native pose identification based on the quantum-mechanical description of protein–ligand interactions and implicit COSMO solvation

Current virtual screening tools are fast, but reliable scoring is elusive. Here, we present the "SQM/COSMO filter", a novel scoring function featuring a quantitative semiempirical quantum mechanical (SQM) description of all types of noncovalent interactions coupled with implicit COSMO solvation. We show unequivocally that it outperforms eight widely used scoring functions. The accuracy and chemical generality of the SQM/COSMO filter make it a perfect tool for late stages of virtual screening

The origins of species richness in the Hymenoptera: insights from a family-level supertree

<p>Abstract</p> <p>Background</p> <p>The order Hymenoptera (bees, ants, wasps, sawflies) contains about eight percent of all described species, but no analytical studies have addressed the origins of this richness at family-level or above. To investigate which major subtaxa experienced significant shifts in diversification, we assembled a family-level phylogeny of the Hymenoptera using supertree methods. We used sister-group species-richness comparisons to infer the phylogenetic position of shifts in diversification.</p> <p>Results</p> <p>The supertrees most supported by the underlying input trees are produced using matrix representation with compatibility (MRC) (from an all-in and a compartmentalised analysis). Whilst relationships at the tips of the tree tend to be well supported, those along the backbone of the tree (e.g. between Parasitica superfamilies) are generally not. Ten significant shifts in diversification (six positive and four negative) are found common to both MRC supertrees. The Apocrita (wasps, ants, bees) experienced a positive shift at their origin accounting for approximately 4,000 species. Within Apocrita other positive shifts include the Vespoidea (vespoid wasps/ants containing 24,000 spp.), Anthophila + Sphecidae (bees/thread-waisted wasps; 22,000 spp.), Bethylidae + Chrysididae (bethylid/cuckoo wasps; 5,200 spp.), Dryinidae (dryinid wasps; 1,100 spp.), and Proctotrupidae (proctotrupid wasps; 310 spp.). Four relatively species-poor families (Stenotritidae, Anaxyelidae, Blasticotomidae, Xyelidae) have undergone negative shifts. There are some two-way shifts in diversification where sister taxa have undergone shifts in opposite directions.</p> <p>Conclusions</p> <p>Our results suggest that numerous phylogenetically distinctive radiations contribute to the richness of large clades. They also suggest that evolutionary events restricting the subsequent richness of large clades are common. Problematic phylogenetic issues in the Hymenoptera are identified, relating especially to superfamily validity (e.g. "Proctotrupoidea", "Mymarommatoidea"), and deeper apocritan relationships. Our results should stimulate new functional studies on the causes of the diversification shifts we have identified. Possible drivers highlighted for specific adaptive radiations include key anatomical innovations, the exploitation of rich host groups, and associations with angiosperms. Low richness may have evolved as a result of geographical isolation, specialised ecological niches, and habitat loss or competition.</p

Exploring the Everyday Life Information Needs, Practices, and Challenges of Emerging Adults with Intellectual Disabilities

This dissertation research addresses a gap in the library and information science literature on everyday life information (ELI) needs and experiences of emerging adults with intellectual disabilities (I/DD). Emerging adulthood refers to the period between the late teen years and mid-twenties. Although this is a period of significant change for all young people, for individuals with I/DD this life stage is recognized as one of the most stressful times of life. The challenges experienced by these individuals suggest considerable areas of information need. This case study research explored the ELI needs, practices, and challenges of four emerging adults with I/DD. Employing a participatory research approach, participants played a central role in the inquiry process by offering time, input, and invitations into their daily lives for observation and study. Data collection methods included semi-structured interviews, participant/non-participant observations, artwork, photography, and document review of IEP and PCP reports. Analyses revealed four rich and multifaceted lives led by individuals exhibiting a wide range of both formidable and whimsical ELI needs. Twenty-nine categories of ELI need were identified, including multiple subcategories. All four participants displayed high motivation and great initiative in their ELI practice as information seekers, consumers, producers, managers, and providers. They also employed a wide range of tools, resources, and strategies to their advantage, despite considerable challenges - inherent and imposed. Barriers inhibiting information access were identified under the following categories: intrapersonal, physical, economic, social, and institutional. Results from this study parallel findings from other youth-ELI studies. The need for cognitively accessible information and proactive LIS service was underscored in each case study as a necessary mean toward supporting the developmental processes of emerging adults with I/DD and the development of knowledge, skills, and dispositions for self-actualization and enhanced adult life outcomes. A person-centered, outcomes-oriented model for LIS research and practice is proposed with emphasis on a strengths-based approach that capitalizes on individual capabilities, interests, and life priorities in recognition of the whole person. Five target areas are identified for LIS attention: individual capacity building, social capital, developmental processes, quality of life, and enabling environments.Doctor of Philosoph

Evidence for Quadratic Tidal Tensor Bias from the Halo Bispectrum

The relation between the clustering properties of luminous matter in the form of galaxies and the underlying dark matter distribution is of fundamental importance for the interpretation of ongoing and upcoming galaxy surveys. The so called local bias model, where galaxy density is a function of local matter density, is frequently discussed as a means to infer the matter power spectrum or correlation function from the measured galaxy correlation. However, gravitational evolution generates a term quadratic in the tidal tensor and thus non-local in the density field, even if this term is absent in the initial conditions (Lagrangian space). Because the term is quadratic, it contributes as a loop correction to the power spectrum, so the standard linear bias picture still applies on large scales, however, it contributes at leading order to the bispectrum for which it is significant on all scales. Such a term could also be present in Lagrangian space if halo formation were influenced by the tidal field. We measure the corresponding coupling strengths from the matter-matter-halo bispectrum in numerical simulations and find a non-vanishing coefficient for the tidal tensor term. We find no scale dependence of the bias parameters up to k=0.1 h/Mpc and that the tidal effect is increasing with halo mass. While the Lagrangian bias picture is a better description of our results than the Eulerian bias picture, our results suggest that there might be a tidal tensor bias already in the initial conditions. We also find that the coefficients of the quadratic density term deviate quite strongly from the theoretical predictions based on the spherical collapse model and a universal mass function. Both quadratic density and tidal tensor bias terms must be included in the modeling of galaxy clustering of current and future surveys if one wants to achieve the high precision cosmology promise of these datasets.Comment: 14 pages, 4 figures, 1 tabl

An algorithm for the direct reconstruction of the dark matter correlation function from weak lensing and galaxy clustering

The clustering of matter on cosmological scales is an essential probe for studying the physical origin and composition of our Universe. To date, most of the direct studies have focused on shear-shear weak lensing correlations, but it is also possible to extract the dark matter clustering by combining galaxy-clustering and galaxy-galaxy-lensing measurements. In this study we develop a method that can constrain the dark matter correlation function from galaxy clustering and galaxy-galaxy-lensing measurements, by focusing on the correlation coefficient between the galaxy and matter overdensity fields. To generate a mock galaxy catalogue for testing purposes, we use the Halo Occupation Distribution approach applied to a large ensemble of N-body simulations to model pre-existing SDSS Luminous Red Galaxy sample observations. Using this mock catalogue, we show that a direct comparison between the excess surface mass density measured by lensing and its corresponding galaxy clustering quantity is not optimal. We develop a new statistic that suppresses the small-scale contributions to these observations and show that this new statistic leads to a cross-correlation coefficient that is within a few percent of unity down to 5 Mpc/h. Furthermore, the residual incoherence between the galaxy and matter fields can be explained using a theoretical model for scale-dependent bias, giving us a final estimator that is unbiased to within 1%. We also perform a comprehensive study of other physical effects that can affect the analysis, such as redshift space distortions and differences in radial windows between galaxy clustering and weak lensing observations. We apply the method to a range of cosmological models and show the viability of our new statistic to distinguish between cosmological models.Comment: 23 pages, 14 figures, accepted by PRD; minor changes to V1, 1 new figure, more detailed discussion of the covariance of the new ADSD statisti

History of Plio-Pleistocene Climate in the Northeastern Atlantic, Deep Sea Drilling Project Hole 552A

DSDP Hole 552A, cored with the HPC on Hatton Drift, represents an almost complete and undisturbed sediment section spanning the late Neogene and Quaternary. Lithologic, faunal, isotopic, and paleomagnetic analyses indicate that the section represents the most complete deep sea record of climatic evolution hitherto recovered at high latitudes in the northern hemisphere. A glacial record of remarkable resolution for the late Pliocene and Pleistocene is provided by oxygen and carbon isotope ratios in benthic foraminifers. In the upper part of the section, the whole of the standard oxygen isotope record of the past million years is well preserved. The onset of ice-rafting and glacial-interglacial alternations occurs at about 2.4 m.y. ago