gebhart/patrepeval huggingface dataset:
Efficient Catalytic System for Synthesis of <i>trans</i>-Stilbene from Diphenylacetylene Using Rh-Based Intermetallic Compounds (2014)

A series of Rh-based intermetallic compounds supported on silica (RhmM′n/SiO2, M′ = Bi, Ge, In, Sb, and Sn) were prepared and tested as catalysts for trans-stilbene (trans-ST) synthesis from diphenylacetylene (DPA) in H2 atmosphere. Rh2Sb/SiO2 exhibited high catalytic activity in the semihydrogenation of DPA to cis-ST and subsequent isomerization to trans-ST, with a smaller capability of overhydrogenation to diphenylacetylene (DPE) than Rh/SiO2, affording a moderate yield of trans-ST (58%) after complete conversion of DPA. RhSb/SiO2 possesses a unique hydrogenation property capable of half-hydrogenation but minimal overhydrogenation, which enables highly selective isomerization of cis-ST to trans-ST. A tandem catalytic system using RhSb/SiO2 and Pd3Bi/SiO2 afforded 88% yield of trans-ST. These results are the first examples of the effective synthesis of trans-ST from DPA using heterogeneous metallic catalysts.
Stationary State of a High-Temperature Gas-Insulated Plasma Column (1961)

On the basis of a simplified theoretical model an analysis is given of the stationary state of a cylindrical column of fully ionized high-pressure plasma, which is heated by an axial current and cooled by heat conduction in the radial direction across the self-magnetic field of the current. The radial distributions of current, magnetic field, temperature, pressure, and density are calculated and discussed. The power needed to maintain a stationary state at very high temperatures is found to be moderate. The relative importance of radiation losses is considered and found to be small in a certain range of parameters.
Microtubule-Disrupting Chemotherapeutics Result in Enhanced Proteasome-Mediated Degradation and Disappearance of Tubulin in Neural Cells (2010)

We sought to examine the effects of microtubule-targeting agents (MTA) on neural cells to better understand the problem of neurotoxicity, their principal side effect, and to possibly develop a model of clinical toxicity. Studies showed that microtubule-depolymerizing agents (MDA) not only disassembled microtubules in neural HCN2 cells but also led to rapid disappearance of tubulin, and that this was specific for MDAs. Tubulin levels decreased to 20% as early as 8 hours after adding vincristine, and to 1% to 30% (mean, 9.8 +/- 7.6%; median of 7%) after 100 nmol/L vincristine for 24 hours. This disappearance was reversible. An increase in both glu-terminated and acetylated tubulin, markers of stable tubulin, preceded reaccumulation of soluble tubulin, suggesting a priority for stabilizing tubulin first as microtubules before replenishing the soluble pool. Similar results were shown with other MDAs. Furthermore, microtubule reassembly did not arise from a central focus but instead appeared to involve dispersed nucleation, as evidenced by the appearance of small, stable microtubule stubs throughout the cytoplasm. In contrast, experiments with four nonneural "normal" cell lines and four cancer cell lines resulted in microtubule destabilization but only modest tubulin degradation. Evidence for proteasome-mediated degradation was obtained by demonstrating that adding a proteasome inhibitor before vincristine prevented tubulin disappearance. In summary, MDAs lead to rapid disappearance of tubulin in neural but not in other normal or cancer cells. These results underscore the fine control that occurs in neural cells and may further our understanding of neurotoxicity following MDAs.
Methods of conjugate gradients for solving linear systems (1952)

An iterative algorithm is given for solving a system Ax=k of n linear equations in n unknowns. The solution is given in n steps. It is shown that this method is a special case of a very general method which also includes Gaussian elimination. These general algorithms are essentially algorithms for finding an n dimensional ellipsoid. Connections are made with the theory of orthogonal polynomials and continued fractions.
pH-dependent Conformational Properties of Saposins and Their Interactions with Phospholipid Membranes (1995)

Saposins A, B, C, and D are small lysosomal glycoproteins released by proteolysis from a single precursor polypeptide, prosaposin. We have presently investigated the conformational states of saposins and their interaction with membranes at acidic pH values similar to those present in lysosomes. With the use of phase partitioning in Triton X-114, experimental evidence was provided that, upon acidification, saposins (Sap) A, C, and D acquire hydrophobic properties, while the hydrophilicity of Sap B is apparently unchanged. The pH-dependent exposure of hydrophobic domains of Sap C and D paralleled their pH-dependent binding to large unilamellar vesicles composed of phosphatidylcholine, phosphatidylserine, and cholesterol. In contrast, the binding of Sap A to the vesicles was very restricted, in spite of its increased hydrophobicity at low pH. A low affinity for the vesicles was also shown by Sap B, a finding consistent with its apparent hydrophilicity both at neutral and acidic pH. At the acidic pH values needed for binding, Sap C and D powerfully destabilized the phospholipid membranes, while Sap A and B minimally affected the bilayer integrity. In the absence of the acidic phospholipid phosphatidylserine, the induced destabilization markedly decreased. Of the four saposins, only Sap C was able to promote the binding of glucosylceramidase to phosphatidylserine-containing membranes. This result is consistent with the notion that Sap C is specifically required by glucosylceramidase to exert its activity. Our finding that an acidic environment induces an increased hydrophobicity in Sap A, C, and D, making the last two saposins able to interact and perturb phospholipid membranes, suggests that this mechanism might be relevant to the mode of action of saposins in lysosomes.
Extracellular vesicles derived from MSCs activates dermal papilla cell in vitro and promotes hair follicle conversion from telogen to anagen in mice (2017)

Hair loss is a common medical problem. In this study, we investigated the proliferation, migration, and growth factor expression of human dermal papilla (DP) cells in the presence or absence of treatment with mesenchymal stem cell extracellular vesicles (MSC-EVs). In addition, we tested the efficacy of MSC-EV treatment on hair growth in an animal model. MSC-EV treatment increased DP cell proliferation and migration, and elevated the levels of Bcl-2, phosphorylated Akt and ERK. In addition; DP cells treated with MSC-EVs displayed increased expression and secretion of VEGF and IGF-1. Intradermal injection of MSC-EVs into C57BL/6 mice promoted the conversion from telogen to anagen and increased expression of wnt3a, wnt5a and versican was demonstrated. The first time our results suggest that MSC-EVs have a potential to activate DP cells, prolonged survival, induce growth factor activation in vitro, and promotes hair growth in vivo.
Understanding web images by object relation network (2012)

This paper presents an automatic method for understanding and interpreting the semantics of unannotated web images. We observe that the relations between objects in an image carry important semantics about the image. To capture and describe such semantics, we propose Object Relation Network (ORN), a graph model representing the most probable meaning of the objects and their relations in an image. Guided and constrained by an ontology, ORN transfers the rich semantics in the ontology to image objects and the relations between them, while maintaining semantic consistency (e.g., a soccer player can kick a soccer ball, but cannot ride it). We present an automatic system which takes a raw image as input and creates an ORN based on image visual appearance and the guide ontology. We demonstrate various useful web applications enabled by ORNs, such as automatic image tagging, automatic image description generation, and image search by image.
Presidential Appointments and Personnel (2011)

This article reviews some recent advances in research on presidential appointments and personnel. I focus specifically on research analyzing changes in the institutional environment of presidential personnel, how presidents make decisions about whom to appoint, and the effects of presidential appointees on outputs. I explore what we know about how presidents have worked to change institutions surrounding presidential personnel by increasing the number of appointees and augmenting White House personnel operations. I examine how presidents decide what factors to value when choosing personnel. When do presidents value loyalty, competence, campaign support, or other characteristics of potential appointees? Finally, I examine the effects of appointees on outputs. What influence do appointees have over outputs and why do some have more influence than others? I describe the general trajectory of research in each area as well as some emerging issues confronting scholars in these areas.
Probabilistic Quantitative Precipitation Estimation in Complex Terrain (2006)

Abstract This paper describes a flexible method to generate ensemble gridded fields of precipitation in complex terrain. The method is based on locally weighted regression, in which spatial attributes from station locations are used as explanatory variables to predict spatial variability in precipitation. For each time step, regression models are used to estimate the conditional cumulative distribution function (cdf) of precipitation at each grid cell (conditional on daily precipitation totals from a sparse station network), and ensembles are generated by using realizations from correlated random fields to extract values from the gridded precipitation cdfs. Daily high-resolution precipitation ensembles are generated for a 300 km × 300 km section of western Colorado (dx = 2 km) for the period 1980–2003. The ensemble precipitation grids reproduce the climatological precipitation gradients and observed spatial correlation structure. Probabilistic verification shows that the precipitation estimates are reliable, in the sense that there is close agreement between the frequency of occurrence of specific precipitation events in different probability categories and the probability that is estimated from the ensemble. The probabilistic estimates have good discrimination in the sense that the estimated probabilities differ significantly between cases when specific precipitation events occur and when they do not. The method may be improved by merging the gauge-based precipitation ensembles with remotely sensed precipitation estimates from ground-based radar and satellites, or with precipitation and wind fields from numerical weather prediction models. The stochastic modeling framework developed in this study is flexible and can easily accommodate additional modifications and improvements.
Rapid stimulation of amyloid precursor protein release by epidermal growth factor: role of protein kinase C (1997)

The amyloid precursor protein (APP) of Alzheimer's disease is a transmembrane protein that is cleaved by an uncharacterized enzyme known as alpha-secretase within its extracellular/intraluminal domain after the activation of guanine nucleotide-binding protein-coupled receptors linked to phosphoinositide hydrolysis. The secretory process results in the release of large soluble derivatives of APP (APPs), and, when elicited by muscarinic receptor activation, exhibits both protein kinase C (PKC)-dependent and tyrosine phosphorylation-dependent components [Slack, Breu, Petryniak, Srivastava and Wurtman (1995) J. Biol. Chem. 270, 8337-8344]. In this report we examine the regulation of the release of APPs by epidermal growth factor (EGF) receptors, which possess intrinsic tyrosine kinase activity, and are coupled to a variety of effectors including phosphoinositide-specific phospholipase Cgamma. In A431 cells, EGF caused time-dependent and dose-dependent increases in the formation of inositol phosphates in cultures prelabelled with myo--3H-inositol, and in the release of APPs into the culture medium; the two responses exhibited similar time courses and EC50 values for EGF. Concomitant with these effects, there were concentration-dependent (3-300 ng/ml) increases in the phosphorylation of tyrosine residues in several proteins, including the EGF receptor itself. The specific PKC antagonist GF 109203X decreased the effect of EGF by approx. 35% at a concentration that abolished the stimulation of the release of APPs by the PKC activator PMA. Tyrphostin AG 1478, an inhibitor of EGF receptor tyrosine kinase, abolished the EGF-induced release of APPs. These results demonstrate that in A431 cells, activation of the EGF receptor stimulates alpha-secretase activity by a mechanism that is partly dependent on PKC activity.
A fast operating magnetically controlled switch for 1 kA (1985)

The power of fully superconducting rectifiers can be improved by increasing either the operating frequency or the transformer primary inductance [1]. The frequency is usually limited by the recovery time of thermally controlled switches. In order to achieve a higher switching speed, magnetically controlled switches are preferable [1,2]. This paper describes a magnetically controlled switch which can be used for currents up to 500 A at 25 Hz. The switch element, consisting of several Nb1%Zr multifilamentary superconductors, is placed between two concentric solenoids which generate the necessary magnetic field. The Nb1%Zr superconductor is well suited for this purpose because of its relatively low critical field (≃ 0.75 T) and high maximum current density (about 5.10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">9</sup> A/m <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> below 0.3 T).
A comparison of two modified Kjeldahl digestion techniques for multi‐element plant analysis with conventional wet and dry ashing methods (1980)

Abstract The efficiency of two modified Kjeldahl procedures (H2SO4‐H2‐O2‐Li2SO4‐Se and H2SO4‐Na2SO4) for digestion of plant tissue for analysis of P, K, Ca and Mg contents was compared with a conventional wet (HNO3‐HClO4) and a dry ashing procedure. Six plant tissues were chosen as test material: leaves of Malus pumila Mill., Medicago sativa L., Dactylis glomerata L., fruit and wood tissue of M. pumila and Nothofagus mensiesii Oerst. leaf litter. Apart from low P contents of M. pumila wood tissue by dry ashing, the mean P, K, Ca and Mg contents as determined after the four digestion procedures were in good agreement. Furthermore, the precision of the data for each element was generally quite similar for each of the digestion methods. The N contents determined by the two modified and a conventional Kjeldahl procedure (H2SO4‐K2SO4‐CuSO4‐Se) also agreed closely.
Control of cortical interneuron migration by neurotrophins and PI3-kinase signaling (2002)

During telencephalic development, cells from the medial ganglionic eminence (MGE) are thought to migrate to the neocortex to give rise to a majority of cortical GABAergic interneurons. By combining time-lapse video-microscopy, immunofluorescence and pharmacological perturbations in a new in vitro migration assay, we find that MGE-derived cells migrate through the entire extent of the cortex and into the CA fields of the hippocampus, but avoid the dentate gyrus. Migrating neurons initially travel within the marginal zone and intermediate zone, and can enter the cortical plate from either location. Tangential migration is strongly stimulated by BDNF and NT4 and attenuated by the Trk-family inhibitor, K252a, suggesting that migration is regulated by TrkB signaling. Furthermore, TrkB-null mice show a significant decrease in the number of calbindin-positive neurons migrating tangentially in the embryonic cortex. BDNF and NT4 cause rapid activation of PI3-kinase in MGE cells, and inhibition of PI3-kinase (but not of MAP kinase or PLCgamma) dramatically attenuates tangential migration. These observations suggest that TrkB signaling, via PI3-kinase activation, plays an important role in controlling interneuron migration in the developing cerebral cortex.
MHC molecules protect T cell epitopes against proteolytic destruction (1992)

There is a subtle duality in the role of proteolytic enzymes in Ag processing. They are required to fragment protein Ag ingested by APC. However, prolonged exposure to proteolytic enzymes may lead to a complete degradation of the Ag, leaving nothing for the T cell system to recognize. What ensures that some of the Ag is salvaged? Using a cell-free system we demonstrate that an Ag fragment, once bound to a MHC class II molecule, is effectively protected against proteolytic destruction by cathepsin B and pronase E. The bound fragment, however, can be modified by aminopeptidase N. We suggest that MHC class II molecules play an important regulatory role in the physiologic processing of Ag.
Glucokinase Regulatory Network in Pancreatic β-Cells and Liver (2006)

The low-affinity glucose-phosphorylating enzyme glucokinase (GK) is the flux-limiting glucose sensor in liver and β-cells of the pancreas. Furthermore, GK is also expressed in various neuroendocrine cell types. This review describes the complex network of GK regulation, which shows fundamental differences in liver and pancreatic β-cells. Tissue-specific GK promoters determine a higher gene expression level and glucose phosphorylation capacity in liver than in pancreatic β-cells. The second hallmark of tissue-specific GK regulation is based on posttranslational mechanisms in which the high-affinity regulatory protein in the liver undergoes glucose- and fructose-dependent shuttling between cytoplasm and nucleus. In β-cells, GK resides outside the nucleus but has been reported to interact with insulin secretory granules. The unbound diffusible GK fraction likely determines the glucose sensor activity of insulin-producing cells. The bifunctional enzyme 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFK-2/FBPase-2) has been identified as an activating binding partner of β-cell GK, increasing the Vmax value of the enzyme, while the S0.5 value for glucose remains unchanged. This effect is likely due to stabilization of a catalytically active enzyme conformation. The identification of chemical activators of GK paved the way to determining its crystal structure, revealing a catalytically less active super open conformation and a catalytically active closed conformation with a normal affinity for glucose. The glucose sensor function of GK in liver and β-cells results from the synergy of its regulatory properties with its transcriptionally and posttranslationally controlled levels. These factors have to be taken into account in designing pharmacotherapy for type 2 diabetes.
STUDIES ON DEXTRANSUCRASE (1965)

1. Cell-free extracts prepared from strains of Leuc. mesenteroides grown on sucrose were found to reveal the production of riboflavinylglucoside from sucrose and riboflavin. Moreover, it was found that the extract utilized only sucrose as a glucosyl donor in the formation of riboflavinylglucoside, while glucose itself was quite ineffective.2. The intracellular enzyme revealing formation of riboflavinylglucoside was isolated by ammonium sulfate precipitation from the cell-free extract of the strain NRRL B-1299 grown on sucrose.3. Maximum activity of the enzyme was observed in the range of pH 4.5 to 5.3 and around at 30°. The enzyme was found to be fairly sensitive to heat as it was almost completely inactivated by heating at 45° for 10 minutes.4. By the action of the enzyme, riboflavinyloligosaccharides were observed to be formed through the successive transfer of glucosyl group between riboflavin compounds and sucrose.
Imaging and Characteristics of a Bimaterial Microcantilever FPA Fabricated using Bulk Silicon Processes (2012)

For a focal plane array (FPA) fabricated with a surface sacrificial layer process, the IR flux must transmit through the silicon substrate and the air gap before it reaches the cantilever pixels. Part of the IR radiation energy is therefore lost owing to the reflection and absorption caused by the silicon substrate. We fabricate an infrared FPA consisting of 128 × 128 microcantilever pixels by using a novel bulk micro-electro-mechanical-system process. Thermal images of persons at room temperature are captured to demonstrate the IR imaging capability of the FPA. For the proposed device, the thermal response is calculated to be 4.03 × 10−3, the thermo-mechanical sensitivity is measured to be 0.273 μm/K, the noise equivalent temperature difference is measured to be 200 mK by a gray level change method and the time constant is calculated to be 15 ms under a 10 mTorr pressure.
Architectural Support For Unified Memory Controller (2016)

Advances in semiconductor fabrication technology and processor architecture has resulted in development of high performance processors. These processors have multi – core, thread architecture that further exacerbates memory demand. Sustainable performance improvements on these architectures require contemporary memories to provide high bandwidth and capacity at low power along with several other constraints. Although conventional memory systems have been constantly pushed to meet these requirements, disparity between processor and memory performance is ever increasing. This results in significant performance bottleneck.\nRecent research in memory technologies has resulted in development of novel non - volatile memory technologies (PCM, MRAM). These memories offer several advantages such as high scalability, capacity and bandwidth at low power and can further improve overall system performance. Since these technologies are fundamentally different than contemporary memories, a new framework is required to integrate them in current memory architecture. Previously, researchers relied on independent memory controllers to integrate these memories within a single heterogeneous system. However with reduction in VLSI feature size, controllers are now placed on the processor die itself. These trends point towards the urge of developing a new memory controller framework that is technology independent and can benefit from multiple memory technologies. One such framework is Universal Memory Controller (UniMA). Throughout our study we investigate design and performance overheads in UniMA framework and propose several design alternatives. First, we analyze physical token passage topologies in terms of performance, cost and reliability. Analysis shows that bus topology for token passage is better suited for desktop and mobile applications. Next, we propose new shared channel ownership protocols namely static token assignment, individual token hold and dynamic token assignment. These token assignment policies aim at reducing overall token passage overhead along with maintaining fairness on the shared channel. Results indicate that longer token passage overheads can be successfully hidden in memory intensive applications. Further, dynamic token passage offers best performance by adapting to the current memory demands. Finally, we analyze the effect of request reordering and page management on the overall performance of UniMA framework. Results indicate that closed page policy offers best performance in multi - threaded environment.
Probiotics and the Treatment of Infectious Diarrhea (2005)

From the Monmouth Medical Center, Long Branch NJ, and Drexel University School of Medicine, Philadelphia, PA