615 research outputs found

    General Relativity and Gravitation: A Centennial Perspective

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    To commemorate the 100th anniversary of general relativity, the International Society on General Relativity and Gravitation (ISGRG) commissioned a Centennial Volume, edited by the authors of this article. We jointly wrote introductions to the four Parts of the Volume which are collected here. Our goal is to provide a bird's eye view of the advances that have been made especially during the last 35 years, i.e., since the publication of volumes commemorating Einstein's 100th birthday. The article also serves as a brief preview of the 12 invited chapters that contain in-depth reviews of these advances. The volume will be published by Cambridge University Press and released in June 2015 at a Centennial conference sponsored by ISGRG and the Topical Group of Gravitation of the American Physical Society.Comment: 37 page

    Dust Mitigation on Mars Using an Electrostatic Precipitator

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    The Martian atmosphere contains large amounts of dust, which are lofted by dust devils and dust storms. Some of this dust, particles on the order of 2-4 m, never settle and are constantly present in the atmosphere. Therefore, in order to utilize the planet's atmosphere for production of consumables, like oxygen and methane, this dust must be removed before the commodity production can begin. The electrostatic precipitator is currently being studied at Kennedy Space Center as a realistic option for removing this dust. This project covers the results, to date, of the dust flow initiation, control, and analysis inside the electrostatic precipitator, which is to be modelled after various dusty Martian atmospheric conditions

    Post(racial)-Malone: (Un)conscious Habits of White Iverson

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    This phenomenological qualitative study explored the gender performativity of protest masculinity in a multi-institutional study of white male-identified fraternity men. The participants expressed sentiments of dispossession, postracial attitudes, and performed cultural appropriation. Participants appropriated Black culture because they considered this synonymous with their own lack of power and privilege, which they believe has been dispossessed. Implications are provided to suggest how campus-based professionals can further disrupt the (un) conscious habits of whiteness in fraternity men and forms of white supremacy through collaborative programming and campus-wide efforts

    Characterization of Two Distinct Calcium-Binding Sites in the Amino-Terminus of Human Profilaggrin

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    Profilaggrin is a large phosphorylated protein (approximately 400 kDa In humans) that is expressed in the granular cells of epidermis where it forms a major component of keratohyalin. It consists of multiple copies of similar filaggrin units plus amino- and carboxy-terminal domains that differ from filaggrin. Proteolytic processing of profilaggrin during terminal differentiation results in the removal of these domains and generation of monomeric filaggrin units, which associate with keratin intermediate filaments to form macrofibrils in the stratum corneum. The amino-terminal domain contains two calcium-binding motifs similar to the EF-hands found in the S-100 family of calcium-binding proteins. In this report, we expressed the 293-residue amino-terminal pro-domain of human profilaggrin as a polyhistidine fusion protein in Escherichia coli, and characterized calcium binding by a 45Ca++ binding assay and fluorescence emission spectroscopy. fluorescence measurements indicated that the profilaggrin polypeptide undergoes conformational changes upon the removal of Ca++ with ethylenediamine tetraacetic acid, demonstrating the presence of two calcium-binding sites with affinities for calcium that differ ninefold (1.4 × 10-4 M and 1.2 × 10-3 M). We suggest that this functional calcium-binding domain at the amino-terminus of human profilaggrin plays a role in profilaggrin processing and in other calcium-dependent processes during terminal differentiation of the epidermis

    Verbal Communication Skills Requirements for Information Systems Professionals

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    The role of information systems (IS) professionals in organizations has changed through the years, from one who works mostly with technically oriented peers, to one who spends a significant amount of time interacting with people who are involved in the functional areas of the organization. In many organizations, IS professionals are assigned permanently to the user area and they are expected to not only be technically competent, but also be competent in the user\u27s area. This move of IS professionals to the functional areas necessitates that they communicate more with the functional users whose IS needs they are fulfilling. The users, on the other hand, are also required to interact and communicate more with the IS people. With the move toward distributed IS, users are becoming more involved in the specification, design and sometimes even construction of their own systems. It is therefore imperative that analysts and users be able to communicate with each other unequivocally, so that the systems are specified and developed properly. This research investigated the verbal communication skills requirements for IS practicing professionals and new university graduates. A survey was used for data collection. It was sent to IS professionals in several large organizations, that represented the industry in general. A nearly perfect response rate was achieved. The findings are useful for both IS professionals and university programs. Organizations can use the findings to identify areas of weaknesses in the skills of their IS personnel and eliminate them with continuing education. Universities can use the findings to identify skills that they may not be currently emphasizing in their curricula and make necessary adjustments

    Turbine Remanufacture - One Option For Reliability And Efficiency Improvement.

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    LecturePg. 95-110A case study of a remanufacture of a steam turbine is presented. The turbine has been in service for 20 years. Thermal and physical stresses have taken their toll on the turbine casing and supporting hardware. Remanufacture was planned with innovative processes and state-of-the-art component upgrades. A unique heat treatment process was designed to reshape the casing and relieve residual stresses thermally induced into the casing over its operating life. Using heat to reshape the case minimized the amount of remachining time required. A team of three vendors was combined to maximize technical and physical resources and accomplish this task in 24 days. The goals of the remanufacture included: • Recovery of lost horsepower and efficiency due to steam path deterioration • Increase efficiency through the application of packing, tip, and nozzle seal upgrades • Elimination of chronic maintenance problems. Major topics include: • Casing disassembly and damage assessment • Weld restoration of erosion damage and steam path blading • Distortion modelling and evaluation • Heat treatment of case • Assessment of heat treatment results • Machining steps required • Design and installation of retractable packing • Design and installation of tip seals and nozzle seals • Successful startup and operational histor

    Antenatal steroid exposure and heart rate variability in adolescents born with very low birth weight

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    Reduced heart rate variability (HRV) suggests autonomic imbalance in the control of heart rate and is associated with unfavorable cardiometabolic outcomes. We examined whether antenatal corticosteroid (ANCS) exposure had long-term programming effects on heart rate variability (HRV) in adolescents born with very low birth weight (VLBW)

    Single-Cell Glia and Neuron Gene Expression in the Central Amygdala in Opioid Withdrawal Suggests Inflammation With Correlated Gut Dysbiosis.

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    Drug-seeking in opioid dependence is due in part to the severe negative emotion associated with the withdrawal syndrome. It is well-established that negative emotional states emerge from activity in the amygdala. More recently, gut microflora have been shown to contribute substantially to such emotions. We measured gene expression in single glia and neurons gathered from the amygdala using laser capture microdissection and simultaneously measured gut microflora in morphine-dependent and withdrawn rats to investigate drivers of negative emotion in opioid withdrawal. We found that neuroinflammatory genes, notabl
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