gebhart/patrepeval huggingface dataset:
Replacement of Chromium Electroplating on Gas Turbine Engine Components Using Thermal Spray Coatings (2006)

Hard chromium electroplating is extensively used by aircraft manufacturers and military maintenance depots to provide wear and/or corrosion resistance or to restore dimensional tolerance to components. However, chrome plating utilizes hexavalent chromium, which is a highly toxic carcinogen, and increasingly, stringent environmental and worker-safety regulations are making chrome plating more expensive for the DoD. This document constitutes the final report on a project to qualify high-velocity oxygen-fuel (HVOF) and plasma thermal spray coatings as a replacement for hard chrome plating on gas turbine engine components. Extensive fatigue, fretting wear, salt-fog corrosion, and carbon-seal wear tests were performed on HVOF, WC/17Co, Tribaloy 400, Tribaloy 800, and Cr3C2/20(NiCr), and plasma-sprayed Tribaloy 400 coatings compared to hard chromium. In general, the HVOF WC/17Co coatings demonstrated superior performance. An accelerated test on a TF33 engine containing seven components coated with HVOF WC/17Co showed superior performance to what would have been expected using the standard hard chromium. A cost/benefit analysis indicates that military repair depots that overhaul gas turbine engines can realize substantial savings by converting from hard chrome to HVOF.
Identification of a site on 23S ribosomal RNA located at the peptidyl transferase center. (1984)

3-(4'-Benzoylphenyl)propionyl[3H] Phe-tRNA bound to the peptidyl site of the ribosome is photo-crosslinked exclusively to 23S RNA on irradiation at 320 nm. The site of reaction has been identified both by hybridization and primer-extension experiments as uridine-2584 and uridine-2585, located within the central loop of domain V according to the secondary structure model of 23S RNA. The fact that the covalently crosslinked tRNA retains its ability to form a peptide bond, together with the proximity of this site to the position of several mutations leading to chloramphenicol or erythromycin resistance strongly argue that this region of the 23S-like rRNAs is an integral component of the peptidyl transferase site. On the basis of these results, and from comparative analysis of the 16 available large subunit rRNA sequences, we propose a model for the functional organization of the peptidyl transferase site involving interaction of domains II and V of 23S rRNA.
Neutrophil Elastase Induces MUC 5AC Gene Expression in Airway Epithelium via a Pathway Involving Reactive Oxygen Species (2002)

Neutrophil-predominant airway inflammation and mucus obstruction of the airways are major pathologic features of chronic airway diseases, including cystic fibrosis and chronic bronchitis. Neutrophils release elastase, a serine protease that impairs mucociliary clearance and stimulates goblet cell metaplasia and mucin production. We previously reported that neutrophil elastase increases expression of a major respiratory mucin gene, MUC5AC, by enhancing mRNA stability. However, the molecular mechanisms of elastase-regulated MUC5AC expression are not known. We hypothesized that reactive oxygen species, generated by elastase treatment, mediate MUC5AC gene expression. To test this hypothesis, A549, a respiratory epithelial cell line, was treated with elastase in the presence or absence of the oxygen radical scavenger, dimethylthiourea, or the iron chelator, desferrioxamine. MUC5AC mRNA levels were assessed by Northern analysis. Both antioxidants significantly inhibited elastase-induced MUC5AC gene expression. Dimethylthiourea also inhibited the neutrophil elastase (NE)-induced increase in MUC5AC expression in normal human bronchial epithelial cells. To determine whether elastase treatment generated reactive oxygen species, A549 and normal human bronchial epithelial cells were loaded with dichlorodihydrofluorescein, a fluorescent indicator of oxidative stress. NE treatment increased cellular fluorescence in both cell types, indicating generation of intracellular reactive oxygen species. We conclude that NE treatment increases MUC5AC gene expression by an oxidant-dependent mechanism.
Barriers to the Advancement of Women in Social Work Administration (1985)

This article presents the results of a survey of social workers which examined the relationships of eight barriers to female advancement, the primary one being interest in the pursuit of an administrative career. Through path analysis, both the direct and indirect effects of numerous variables upon career interest for female non-administrators were assessed. A major conclusion was that informal support has much potential as a strategy for achieving gender parity because of its direct effects upon both perception of opportunity for advancement and the appeal of the administrative job and through its indirect effect upon career interest.
Interfacial Design and Chemical Sensing (1994)

This chapter provides a brief overview of the design, characterization, and function of chemically sensitive interfaces. Chemical sensing is an interdisciplinary problem involving the synthesis of new materials, the characterization of materials and interfaces, the design of new methods of signal transduction, and the development of techniques for microfabrication and miniaturization. This chapter summarizes current research in each of these areas, referring to contributions in the literature and to specific chapters in this book in which recent advances are described.
The antiatherogenic role of high-density lipoprotein cholesterol (1998)

Landmark clinical studies in the past 5 years that demonstrated diminished mortality and first coronary events following lowering of low-density lipoprotein (LDL) cholesterol stimulated considerable interest in the medical community. Yet, high-density lipoprotein (HDL) cholesterol, which transports circulating cholesterol to the liver for clearance, clearly also exerts antiatherogenic effects. The Framingham Heart Study produced compelling epidemiologic evidence indicating that a low level of HDL cholesterol was an independent predictor of coronary artery disease (CAD). Emerging experimental and clinical findings are, collectively, now furnishing a solid scientific foundation for this relation. First, the reverse cholesterol transport pathway--including the roles of nascent (pre-beta) HDL, apolipoprotein A-I, lecithin-cholesterol acyltransferase (LCAT), cholesteryl ester transport protein, and hepatic uptake of cholesteryl ester from HDL by liver--is better understood. For example, the identification of a hepatic HDL receptor, SR-BI, suggests a mechanism of delivery of cholesteryl ester to liver that differs from the receptor-mediated uptake of LDL. Second, apolipoprotein A-I, the major protein component of HDL, and 2 enzymes on HDL, paraoxonase and platelet-activating factor acetylhydrolase appear to diminish the formation of the highly atherogenic oxidized LDL. Third, lower levels of HDL cholesterol are associated in a dose-response fashion with the severity and number of angiographically documented atherosclerotic coronary arteries. Fourth, low HDL cholesterol predicts total mortality in patients with CAD and desirable total cholesterol levels (<200 mg/dL). Fifth, low HDL cholesterol concentrations appear to be associated with increased rates of restenosis after percutaneous transluminal coronary angioplasty. In terms of elevating HDL cholesterol, cessation of cigarette smoking, reduction to ideal body weight, and regular aerobic exercise all appear important. Most medications used to treat dyslipidemias will raise HDL cholesterol levels modestly; however, niacin appears to have the greatest potential to do so, and can increase HDL cholesterol up to 30%. Recognizing these data, the most recent report of the National Cholesterol Education Program identified low HDL cholesterol as a CAD risk factor and recommended that all healthy adults be screened for both total cholesterol and HDL cholesterol levels.
Animal models of chronic obstructive pulmonary disease (2008)

The mechanisms involved in the genesis of chronic obstructive pulmonary disease (COPD) are poorly defined. This area is complicated and difficult to model because COPD consists of four separate anatomic lesions (emphysema, small airway remodeling, pulmonary hypertension, and chronic bronchitis) and a functional lesion, acute exacerbation; moreover, the disease in humans develops over decades. This review discusses the various animal models that have been used to attempt to recreate human COPD and the advantages and disadvantages of each. None of the models reproduces the exact changes seen in humans, but cigarette smoke-induced disease appears to come the closest, and genetically modified animals also, in some instances, shed light on processes that appear to play a role.
Anti-Moesin Antibodies in the Serum of Patients with Aplastic Anemia Stimulate Peripheral Blood Mononuclear Cells to Secrete TNF-α and IFN-γ (2009)

Moesin is an intracellular protein that links the cell membrane and cytoskeleton, while also mediating the formation of microtubules and cell adhesion sites as well as ruffling of the cell membrane. To determine the roles of anti-moesin Abs derived from the serum of patients with aplastic anemia (AA) in the pathophysiology of bone marrow failure, we studied the expression of moesin on various blood cells and the effects of anti-moesin Abs on the moesin-expressing cells. The proteins recognized by anti-moesin mAbs were detectable on the surface of T cells, NK cells, and monocytes from healthy individuals as well as on THP-1 cells. The peptide mass fingerprinting of the THP-1 cell surface protein and the knock-down experiments using short hairpin RNA proved that the protein is moesin itself. Both the anti-moesin mAbs and the anti-moesin polyclonal Abs purified from the AA patients' sera stimulated THP-1 cells and the PBMCs of healthy individuals and AA patients to secrete 60-80% as much TNF-alpha as did LPS 100 ng/ml. Although the polyclonal Abs induced IFN-gamma secretion from the PBMCs of healthy individuals only when the PBMCs were prestimulated by anti-CD3 mAbs, the anti-moesin Abs were capable of inducing IFN-gamma secretion from the PBMCs of AA patients by themselves. Anti-moesin Abs may therefore indirectly contribute to the suppression of hematopoiesis in AA patients by inducing myelosuppressive cytokines from immunocompetent cells.
Oxygen-dependent and tissue-specific regulation of erythropoietin gene expression (2004)

Hypoxia-inducible expression of the gene encoding for the glycoprotein hormone erythropoietin (EPO) is the paradigm of oxygen-regulated gene expression. EPO is the main regulator of red blood cell production and more than 100 years of research on the regulation of EPO production have led to the identification of a widespread cellular oxygen sensing mechanism. Central to this signaling cascade is the transcription factor complex hypoxia-inducible factor-1 (HIF-1). Meanwhile, it is known that HIF-1 controls more than 50 oxygen-dependent genes and is now recognized as the main regulator of oxygen homoeostasis in the body. In addition to hypoxic induction, expression of the EPO gene is tightly regulated in a tissue-specific manner. During ontogeny, production of EPO required for erythropoiesis is switched from the fetal liver to the kidneys. Here EPO is mainly synthesized in adulthood. Production of EPO has also been found in organs where it has nonerythropoietic functions: EPO is important for development of the brain and is neuroprotective, whereas it stimulates angiogenesis in the reproductive tract and possibly in other organs. Understanding oxygen and tissue-specific regulation of EPO production is of high relevance for physiology. Moreover, this knowledge might be useful for new therapies to treat human diseases.
Functional Characterization by Genetic Complementation of aroB -Encoded Dehydroquinate Synthase from Mycobacterium tuberculosis H37Rv and Its Heterologous Expression and Purification (2007)

The recent recrudescence of Mycobacterium tuberculosis infection and the emergence of multidrug-resistant strains have created an urgent need for new therapeutics against tuberculosis. The enzymes of the shikimate pathway are attractive drug targets because this route is absent in mammals and, in M. tuberculosis, it is essential for pathogen viability. This pathway leads to the biosynthesis of aromatic compounds, including aromatic amino acids, and it is found in plants, fungi, bacteria, and apicomplexan parasites. The aroB-encoded enzyme dehydroquinate synthase is the second enzyme of this pathway, and it catalyzes the cyclization of 3-deoxy-D-arabino-heptulosonate-7-phosphate in 3-dehydroquinate. Here we describe the PCR amplification and cloning of the aroB gene and the overexpression and purification of its product, dehydroquinate synthase, to homogeneity. In order to probe where the recombinant dehydroquinate synthase was active, genetic complementation studies were performed. The Escherichia coli AB2847 mutant was used to demonstrate that the plasmid construction was able to repair the mutants, allowing them to grow in minimal medium devoid of aromatic compound supplementation. In addition, homogeneous recombinant M. tuberculosis dehydroquinate synthase was active in the absence of other enzymes, showing that it is homomeric. These results will support the structural studies with M. tuberculosis dehydroquinate synthase that are essential for the rational design of antimycobacterial agents.
Development of a Refractory Stage in a Dog Model for Phenylketonuria (1982)

Dogs were fed a continuous diet of phenylalanine (Phe) daily and para-chloro-phenylalanine (p-CPhe), an inhibitor of phenylalanine hydroxylase (PH-ase) every second day. It was reported that such a diet produces a sustained hyperphenylalanemia in rats. We have found, however, that in dogs an initial rise in circulating Phe is followed, after a period of time, by a return to normal levels in spite of diet maintenance. PH-ase ws measured in liver samples obtained from dogs before the start of the above diet and at the time when Phe levels returned to normal. It was found that the post-feeding liver sample had 57%-100% less activity than the normal sample. Accordingly, decline in Phe levels cannot be attributed to an increase in PH-ase activity. Experiments are being initiated using labelled Phe, to investigate whether chronic feeding of Phe and p-CPhe resulted in an intestinal block to Phe absorption, which may explain our experimental findings.
Metabolic flux profiling of Escherichia coli mutants in central carbon metabolism using GC‐MS (2003)

We describe here a novel methodology for rapid diagnosis of metabolic changes, which is based on probabilistic equations that relate GC-MS-derived mass distributions in proteinogenic amino acids to in vivo enzyme activities. This metabolic flux ratio analysis by GC-MS provides a comprehensive perspective on central metabolism by quantifying 14 ratios of fluxes through converging pathways and reactions from [1-13C] and [U-13C]glucose experiments. Reliability and accuracy of this method were experimentally verified by successfully capturing expected flux responses of Escherichia coli to environmental modifications and seven knockout mutations in all major pathways of central metabolism. Furthermore, several mutants exhibited additional, unexpected flux responses that provide new insights into the behavior of the metabolic network in its entirety. Most prominently, the low in vivo activity of the Entner-Doudoroff pathway in wild-type E. coli increased up to a contribution of 30% to glucose catabolism in mutants of glycolysis and TCA cycle. Moreover, glucose 6-phosphate dehydrogenase mutants catabolized glucose not exclusively via glycolysis, suggesting a yet unidentified bypass of this reaction. Although strongly affected by environmental conditions, a stable balance between anaplerotic and TCA cycle flux was maintained by all mutants in the upper part of metabolism. Overall, our results provide quantitative insight into flux changes that bring about the resilience of metabolic networks to disruption.
Temporal lenses for attosecond and femtosecond electron pulses (2009)

Here, we describe the "temporal lens" concept that can be used for the focus and magnification of ultrashort electron packets in the time domain. The temporal lenses are created by appropriately synthesizing optical pulses that interact with electrons through the ponderomotive force. With such an arrangement, a temporal lens equation with a form identical to that of conventional light optics is derived. The analog of ray diagrams, but for electrons, are constructed to help the visualization of the process of compressing electron packets. It is shown that such temporal lenses not only compensate for electron pulse broadening due to velocity dispersion but also allow compression of the packets to durations much shorter than their initial widths. With these capabilities, ultrafast electron diffraction and microscopy can be extended to new domains,and, just as importantly, electron pulses can be delivered directly on an ultrafast techniques target specimen.
A comparative analysis of the foamy and ortho virus capsid structures reveals an ancient domain duplication (2017)

These results indicate that, as well as the duplication of the double domain capsid, there may have been an even more ancient gene-duplication that preceded the double domain structure. In addition, our structure comparison methodology demonstrates a general approach to problems where the components have a high intrinsic level of similarity.
Theophylline in the management of asthma: time for reappraisal? (1994)

Theophylline has been used for several decades in the treatment of asthma and remains the most widely prescribed anti-asthma drug worldwide, although the development of newer anti-asthma medications, especially inhaled steroids, has resulted in declining use of theophylline in industrialized countries. Theophylline is now considered to be a bronchodilator, but it is increasingly recognized that theophylline has other anti-asthma activities, which may be more important. Theophylline, even at low plasma concentrations, inhibits the late asthmatic reaction following allergen challenge. These clinical pharmacological observations are substantiated by experimental animal and in vitro data showing that theophylline has several anti-inflammatory activities relevant to asthma. These include the inhibition of cytokine synthesis and release, the inhibition of inflammatory cell activation and microvascular leakage, and the prevention of airway hyperresponsiveness induced by airway inflammation. Theophylline appears to have immunomodulatory effects, even at relatively low plasma concentrations. Based on these considerations, theophylline can be regarded as a useful alternative to other anti-inflammatory drugs for the chronic treatment of mild to moderate asthma. Theophylline should be used at lower doses to achieve plasma concentrations of 5-10 mg.l-1, which will avoid the risk of side-effects. Further studies are required to evaluate the role of low-dose theophylline as an adjunct to low-dose inhaled steroids in the management of chronic asthma. It may now be appropriate to re-evaluate the role of theophylline in asthma management.
Comparison of Automatic Three-Dimensional Model Builders Using 639 X-ray Structures (1994)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTComparison of Automatic Three-Dimensional Model Builders Using 639 X-ray StructuresJens Sadowski, Johann Gasteiger, and Gerhard KlebeCite this: J. Chem. Inf. Comput. Sci. 1994, 34, 4, 1000–1008Publication Date (Print):July 1, 1994Publication History Published online1 May 2002Published inissue 1 July 1994https://pubs.acs.org/doi/10.1021/ci00020a039https://doi.org/10.1021/ci00020a039research-articleACS PublicationsRequest reuse permissionsArticle Views644Altmetric-Citations534LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts
Contacting versus Insulated Gate Electrode for Si Nanoribbon Field-Effect Sensors Operating in Electrolyte (2011)

Electric response to pH variations is employed to investigate Si nanoribbon field-effect transistors (SiNRFETs) operating in electrolyte with different gate configurations. For devices with a conducting gate electrode for direct metal-electrolyte contact, a well-defined electrode reaction leading to a stable electrode potential is essential for retaining a stable electrical potential of the electrolyte. However, noble metals such as Pt do not meet the stability requirement and consequently bring severe distortions to the electronic response. For devices with an insulated gate electrode relying on the principle of capacitive gate coupling, the capacitance between the gate electrode and the electrolyte should be made much larger than the gate capacitance established between the SiNR and the electrolyte. In this case, an efficient gate control as well as a high stability against external disturbances can be ensured. Further studies show that surface charging of the gate insulator is the main cause responsible for the pH response of the SiNRFETs. Hence, devices with different gate configurations give rise to a comparable pH sensitivity.
Arraycount, an Algorithm for Automatic Cell Counting in Microwell Arrays (2009)

Microscale technologies have emerged as a powerful tool for studying and manipulating biological systems and miniaturizing experiments. However, the lack of software complementing these techniques has made it difficult to apply them for many high-throughput experiments. This work establishes Arraycount, an approach to automatically count cells in microwell arrays. The procedure consists of fluorescent microscope imaging of cells that are seeded in microwells of a microarray system and then analyzing images via computer to recognize the array and count cells inside each microwell. To start counting, green and red fluorescent images (representing live and dead cells, respectively) are extracted from the original image and processed separately. A template-matching algorithm is proposed in which pre-defined well and cell templates are matched against the red and green images to locate microwells and cells. Subsequently, local maxima in the correlation maps are determined and local maxima maps are thresholded. At the end, the software records the cell counts for each detected microwell on the original image in high-throughput. The automated counting was shown to be accurate compared with manual counting, with a difference of approximately 1-2 cells per microwell: based on cell concentration, the absolute difference between manual and automatic counting measurements was 2.5-13%.