gebhart/patrepeval huggingface dataset:
Molecular recognition. Selective ammonium cryptates of synthetic receptor molecules possessing a tetrahedral recognition site (1982)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMolecular recognition. Selective ammonium cryptates of synthetic receptor molecules possessing a tetrahedral recognition siteErnest Graf, Jean Pierre Kintzinger, Jean Marie Lehn, and Jacques LeMoigneCite this: J. Am. Chem. Soc. 1982, 104, 6, 1672–1678Publication Date (Print):March 1, 1982Publication History Published online1 May 2002Published inissue 1 March 1982https://pubs.acs.org/doi/10.1021/ja00370a037https://doi.org/10.1021/ja00370a037research-articleACS PublicationsRequest reuse permissionsArticle Views554Altmetric-Citations73LEARN 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 optionsGet e-Alertsclose Get e-Alerts
Photoluminescence of porous silicon buried underneath epitaxial GaP (1992)

Recent observations of visible, room-temperature photoluminescence in porous Si have stimulated research aimed at the realization of efficient, Si-based electroluminescent devices. To achieve electroluminescence, it may be beneficial to generate carriers with sufficient energy to populate the states of the quantum-confined Si structures. A viable method to accomplish this is to utilize a wide-band-gap heterojunction injector, such as GaP. Toward that end, we report the successful formation of porous Si buried underneath GaP islands, and we demonstrate that the buried porous Si layer exhibits strong photoluminescence (λ≊7000 Å).
Secondary structure of the 3'-untranslated region of yellow fever virus: implications for virulence, attenuation and vaccine development. (1997)

A genetic algorithm-based RNA secondary structure prediction was combined with comparative sequence analysis to construct models of folding for the distal 380 nucleotides of the 3'-untranslated region (3'-UTR) of yellow fever virus (YFV). A number of structural elements that are thermodynamically stable, conserved in shape, and confirmed by compensatory mutations were revealed. At the same time structural polymorphisms were observed among strains of YFV. These polymorphisms showed an association with virulence: all wild and pathogenic strains were likely to be folded in a significantly different way from vaccine strains with reduced virulence. Structural divergence was also found among vaccine strains, with 17DD, the most virulent in the mouse model, exhibiting an intermediate pattern of folding, combining structural features of both wild and vaccine strains. The observation of a strong association between secondary structure of the 3'-UTR and virulence of YFV may help elucidate the molecular mechanisms of virus attenuation and lead to new strategies of vaccine development directed towards rational modification of secondary structure of the 3'-UTR.
THE CORROSION OF ZIRCONIUM AND ITS ALLOYS IN HIGH TEMPERATURE STEAM. PART II. THE UPTAKE OF HYDROGEN DURING CORROSION (1961)

Determinations were made of the uptake of hydrogen by zirconium and a number of its alloys during corrosion by steam at 400 to 600 deg C. With some alloys, the instantaneous percentage uptake increases during corrosion, reaching nearly 100%. Several of the additions which confer corrosion resistance to high- temperature steam lead to high hydrogen uptakes. A ternary copper --tungsten alloy shows low uptakes, at least at 500 deg C and above. Binary iron alloys also appear promising. The mechanism of hydrogen entry is discussed. (auth)
High-performance low-power magnetic tunnel junction based non-volatile flip-flop (2014)

In this paper, a novel magnetic tunnel junction (MTJ) based non-volatile flip-flop (NVFF) is proposed. The separated latch and sensing circuit structure maximizes the performance of latch operation, minimizes power consumption, and improves MTJ lifetime. Furthermore, the merged sensing and write circuit structure reduces area overhead. HSPICE simulation results using a 45-nm technology model show that the proposed NVFF achieves three times smaller power delay product with a 2% smaller layout area than the conventional NVFF.
Studies in Sulphonamides : Part II. Preparation of NI-Hetero-Cyclic Substituted Sulphonamides from Alpha-naphthylamine and Evaluation of their Antibacterial Properties (1969)

A series of N<sup>I</sup>-heterocyclic substituted naphthalene sulphonamides have been prepared in which the hydrogen atom of the sulphonamido group has been substituted by different nuclei, viz., thiazole, benzo­thiazole, pyridine and carbazole rings. All the seventeen compounds so prepared were screened for their antibacterial properties and some of these were found to be active '<em>in</em> <em>vitro' </em>against <em>S. aureus </em>and <strong><em>E. coli.</em></strong>
Diphenyleneiodonium, an NAD(P)H Oxidase Inhibitor, also Potently Inhibits Mitochondrial Reactive Oxygen Species Production (1998)

Diphenyleneiodonium (DPI) has frequently been used to inhibit reactive oxygen species (ROS) production mediated by flavoenzymes, particularly NAD(P)H oxidase. This study was undertaken to examine if DPI could also inhibit production of superoxide and H2O2 by mitochondria, the major source of cellular ROS. Detection of mitochondrial superoxide by lucigenin-derived chemiluminescence (CL) with unstimulated monocytes/macrophages showed that DPI at concentrations that inhibit NAD(P)H oxidase markedly diminished the production of superoxide by mitochondrial respiration. Similarly, the extracellular H2O2 derived from mitochondrial respiration as detected by luminol-derived CL in the presence of horseradish peroxidase was also greatly reduced by DPI. DPI was as potent as rotenone in inhibiting the production of superoxide and H2O2 by mitochondrial respiration. With substrate-supported isolated mitochondria, DPI was shown to reduce mitochondrial superoxide production probably through inhibiting NADH-ubiquinone oxidoreductase (complex I).
Stimulating Khuff Gas Wells with Smart Fluid Placement (2010)

Abstract The objective of many matrix acidizing treatments in the Khuff carbonate formations is to remove drilling damage and enhance productivity after the drilling process. Open hole and multilateral completed wells, present several challenges that prevent an optimum intervention with coiled tubing (CT). Traditional practices have been limited to spot stages of pre-flushes, acid, and diversion systems in front of the formation from toe to heel without proper control over the placement process. Using an innovative workflow, interpretation of distributed temperature surveys (DTS) responses, correlated with reservoir data, assists in selectively placing fluids, maximizing the contact of stimulation fluids with the targeted formation sections. Two field applications, in dual-lateral horizontal open hole gas producers, that demonstrate how to optimize a stimulation treatment as it occurs, were implemented in a field in the Kingdom of Saudi Arabia. In both cases, selective access to pay zones in each lateral was confirmed with DTS profiles. Following the pre-flush and the first acid pass, DTS measurements indicated acid effect over the permeable zones but also detected fluid movement towards non gas bearing thief zones. Foam and energized visco-elastic diverting acid fluids were used to divert acid to the target zones avoiding the lost of all stimulation fluids to the toe in one case and to the heel in the other well. After treatment, the gas production increased from zero to more than two times the expected rate in both wells. Understanding of the flow patterns as fluids are placed in the wellbore was possible. Changes to the fluid placement schedule during the job resulted in optimum acid coverage and efficient diversion confirmed by the downhole measurements. The identification of the thief zones was critical to avoid wasting fluids. This experience, the first ever gas wells in Middle East, represents an opportunity for un-locking production potential in similar gas developments.
Transforming growth factor beta1 treatment leads to an epithelial-mesenchymal transdifferentiation of pancreatic cancer cells requiring extracellular signal-regulated kinase 2 activation. (2001)

The aim of this study was to examine the effects of transforming growth factor (TGF) beta1 on the phenotype and the biological behavior of pancreatic cancer cell lines with and without mutations in the TGF-beta signaling pathway and to elucidate whether the Ras signaling cascade participates in mediating these effects of TGF-beta1. TGF-beta-responsive (PANC-1, COLO-357, and IMIM-PC1) and nonresponsive (CAPAN1 and IMIM-PC2) pancreatic cancer cell lines with activating mutations of the Ki-Ras oncogene were treated with 10 ng/ml TGF-beta1 over time. Phenotypic alterations were studied by electron and phase contrast microscopy and by immunohistochemistry and expression analyses of differentiation markers. The influence of TGF-beta on tumor cell scattering, migration, and invasion was determined. The role of the Ras-mitogen-activated protein kinase kinase (MEK)-extracellular signal-regulated kinase (ERK) cascade in mediating TGF-beta-induced morphological and functional effects were studied by pretreatment with the MEK1 inhibitor PD 98059 and by measuring ERK2 activation using immune complex kinase assays. TGF-beta1 led to a reversible and time-dependent epithelial-mesenchymal transdifferentiation (EMT) in TGF-beta-responsive pancreatic cancer cell lines, characterized by a fibroblastoid morphology and an up-regulation of mesenchymal markers and a down-regulation of epithelial markers. EMT was associated with an increase in tumor cell migration, invasion, and scattering. In the responsive cell lines, TGF-beta1 induced a moderate but sustained activation of ERK2. EMT, the concomitant changes in gene expression, and the invasive and migratory potential were reduced or abolished by pretreatment with the selective MEK1 inhibitor. Thus, in TGF-beta-responsive pancreatic cancer cells with activating Ki-Ras mutations, TGF-beta1 treatment caused an EMT associated with a more invasive phenotype. Cross-talk with the Ras-MEK-ERK-signaling cascade appears to be essential for mediating these effects of TGF-beta1.
Purification and characterization of intracellular proteases of <i>Clostridium perfringens</i> type A (1991)

Five intracellular proteases from sporulating cells of Clostridium perfringens type A were identified and three could be separated by DEAE-Sephacel. Two, I-A and I-B, had caseinolytic activity and one, I-C, was only active on N-benzoyl-DL-arginine-p-nitroanilide. I-A and I-B could each be further separated by Sephacryl S-300 into I-A-1 and I-A-2 and I-B-1 and I-B-2, respectively. I-A-1, a chymotrypsin-like enzyme, was the major intracellular protease, constituting 74% of the intracellular caseinolytic activity. In addition to cytoplasmic proteases both trypsin and chymotrypsin-like enzyme activity was associated with the membrane fraction. I-A-1 had a molecular weight of 330,000, with subunits of 120,000 and 138,000. I-A-1 cleaved a 1200 molecular weight peptide from C. perfringens enterotoxin. Early sporulating cell extracts of C. perfringens contained three presumptive enterotoxin precursors, which disappeared following treatment with I-A. Such cells also contained at least 10 spore coat related proteins, only one (51,500 molecular weight) of which was sensitive to I-A-1. The results indicate a possible role for the major intracellular protease in the processing of C. perfringens enterotoxin and a less important role, if any, in spore coat formation.
Attenuation of Perfluorooctane Sulfonate‐Induced Steatohepatitis by Grape Seed Proanthocyanidin Extract in Mice (2020)

Perfluorooctane sulfonate (PFOS), an environmentally persistent pollutant, has been revealed to elicit hepatic toxicity. In the current study, we investigated the protective role of grape seed proanthocyanidin extract (GSPE) against PFOS-caused steatohepatitis in mice. Animals were exposed intragastrically to PFOS (10 mg/kg/day), GSPE (150 mg/kg/day), or their combination. After 21 days of treatment, mice exposed to PFOS exhibited steatosis, oxidative stress, and inflammation in the liver. Nevertheless, simultaneous administration of GSPE resumed the declined serum hepatic enzyme activities and histological abnormalities in PFOS-exposed mice. Furthermore, GSPE supplementation reduced the contents of triglyceride (TG) and total cholesterol (TC) and expression of lipid metabolism-associated genes <i>CD36</i> and fatty acid-binding protein 4 (<i>FABP4</i>) in the liver of mice treated with PFOS. Moreover, GSPE suppressed the generation of lipid peroxidative product malondialdehyde and restored the activity of superoxide dismutase in the liver of PFOS-exposed mice. In addition, GSPE repressed the PFOS-induced hepatic overproduction of proinflammatory cytokines interleukin-6 (IL-6) and tumor necrosis factor-<i>α</i> (TNF-<i>α</i>). Our results demonstrate that GSPE attenuates PFOS-caused steatohepatitis in mice by regulating lipid metabolism, oxidative stress, and inflammatory response.
Neural networks for learning inverse-kinematics of redundant manipulators (2003)

The problem of learning, the inverse-kinematics of redundant manipulators is considered. It is argued that this is an ill-posed, one-to-many-type problem with infinite solutions. The problem is formulated as a constrained optimization problem to result in a unique solution. Using language multipliers, an energy function is defined to convert the latter into an unconstrained optimization problem. A learning algorithm for the adjustment of the connection weights in the network to minimize the energy function is presented. The trained network, upon receiving end-effector's desired velocity, will produce unique minimum-norm velocity required for the joints.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Deconvolution and Database Search of Complex Tandem Mass Spectra of Intact Proteins (2010)

Top-down proteomics studies intact proteins, enabling new opportunities for analyzing post-translational modifications. Because tandem mass spectra of intact proteins are very complex, spectral deconvolution (grouping peaks into isotopomer envelopes) is a key initial stage for their interpretation. In such spectra, isotopomer envelopes of different protein fragments span overlapping regions on the m/z axis and even share spectral peaks. This raises both pattern recognition and combinatorial challenges for spectral deconvolution. We present MS-Deconv, a combinatorial algorithm for spectral deconvolution. The algorithm first generates a large set of candidate isotopomer envelopes for a spectrum, then represents the spectrum as a graph, and finally selects its highest scoring subset of envelopes as a heaviest path in the graph. In contrast with other approaches, the algorithm scores sets of envelopes rather than individual envelopes. We demonstrate that MS-Deconv improves on Thrash and Xtract in the number of correctly recovered monoisotopic masses and speed. We applied MS-Deconv to a large set of top-down spectra from Yersinia rohdei (with a still unsequenced genome) and further matched them against the protein database of related and sequenced bacterium Yersinia enterocolitica. MS-Deconv is available at http://proteomics.ucsd.edu/Software.html.
The Bowed String As We Know It Today (2004)

Summary The vibration of a bowed string has been studied since the 19th century, and today this problem is the only example of vibration excited by friction which can claim to be well understood. Modern theoretical models embody many of the complicating features of real strings, instruments and bows, and detailed comparisons with experimental studies are allowing fine tuning of the models to take place. The models can be used to explore questions directly relevant to instrument makers and players. The main unresolved question at present concerns th ed escription of the frictional behaviour of rosin, since recent results have shown that the friction model used in most earlier studies is incorrect. Better frictio nm odels are being developed in current research. PACS no. 43.75.De
Dynamic regulation of index implementation for flash memory storages (2010)

Hard disk is gradually replaced by flash memory for its mechanical constraints. And with increase of capacity of flash memory, a large-scale database is able to run it. But the frequent changes of index structure can degrade the performance of flash memory and reduction of service life. Most previous works considered the characteristics of flash memory and improved the performance to some extent. In this paper, we first analyze two representative mechanisms which are suitable to write-oriented and read-oriented workload, respectively. And we pointed out the drawbacks of them. Then we propose a dynamic regulation algorithm for utilizing the superiority of both two mechanisms. With simulation, we can see that the proposed methodology could significantly enhance the efficiency of using index on flash memory storages.
Evaluation of Composts for Suppression of Dollar Spot (<i>Sclerotinia homoeocarpa</i>) of Turfgrass (2002)

The use of composts in turfgrass disease management allows for a reduction in pesticide use in chemical control practices. Disease suppressive properties of composts rely on a number of factors including microbial activity, microbial population dynamics, nutrient concentrations, and other associated chemical and physical factors. Five composts were evaluated for suppression of dollar spot caused by Sclerotinia homoeocarpa. The dollar spot disease suppressive properties of selected compost formulations prepared in different years was evaluated. A third objective was to examine the effects of storage of compost (1 year) on the suppression of dollar spot. Field experiments were conducted in 1998 with compost prepared in 1997 to 1998. Applications of compost every 3 weeks throughout the season suppressed dollar spot of turf to levels not significantly different than applications of chlorothalonil fungicide applied at the manufacturer's lowest recommended preventative rate of 38.4 ml a.i./100 m<sup>2</sup> every 2 weeks (P = 0.05). Single applications of composts at the start of the 1998 season were not effective in reducing disease. Field experiments in 1999 evaluated batches of two selected compost formulations, one batch produced in 1998 to 1999, another stored since production in 1997 to 1998. Composts were effective in suppressing disease to levels not significantly different than the fungicide controls, which showed up to 33% disease in 1998 and up to 31% disease in 1999 (P = 0.05). Storage of composts for up to 1 year did not affect their ability to reduce dollar spot severity (P = 0.05). The use of composts as plant disease suppressants is not likely to replace the use of commercial fungicides in dollar spot management. However, multiple applications of compost may reduce incidence and severity of dollar spot to levels at which chemical control may be reduced or eliminated for a significant portion of the season.
A different violin (2017)

The violin is perhaps an ambitious title for a multi-authored volume of barely 300 pages, yet what else should it have been called? Violinists have long since had their encyclopaedias and books of the violin—all attempting to answer the greatest possible number of questions. The Cambridge companion to the violin, ed. R. Stowell (Cambridge University Press, 1992), for example, casts its net so wide as to cover topics ranging from the instrument’s history to its structure and development, acoustical principles, chief exponents, technique and teaching principles, repertory and pedagogical literature, folk traditions, and its role in jazz. And why not? As the blurb on the dust jacket of the book under review reminds us, ‘with a colorful history that spans 450 years, the violin has proven to be one of the world’s most important and versatile instruments’. It would therefore seem an obvious choice for anyone hoping to add significantly to the extant literature to attempt to reflect the importance and versatility of the violin, both historically and geographically.
External-Rotor <inline-formula><tex-math notation="LaTeX">$6-10$</tex-math></inline-formula> Switched Reluctance Motor for an Electric Bicycle (2015)

As a cost-effective, healthy, and environmental friendly personal mode of transportation, electric bicycles (E-bikes) are gaining an increasing market share from conventional bicycles and automobiles. Considering the legal rules in Ontario, Canada, a 500-W electric motor providing power assist makes the E-bike more attractive to urban commuters. The simple structure, high torque, and power density, as well as the potential for low cost make the switched reluctance machine (SRM) a strong candidate for E-bike traction. In this paper, a three-phase, external-rotor SRM with 6 stator poles and 10 rotor poles is designed for a representative E-bike. The design of an external rotor arrangement of the 6-10 SRM topology has not previously been reported, this brings the challenge of sizing the geometry of this topology, but the solution offers a new contribution to published works. The external-rotor arrangement is chosen to facilitate ease of integration into the wheel hub structure of a typical pedal bicycle. The increased rotor poles yield improved torque ripple reduction than more conventional (i.e., 6-4 and 12-8) SRM design, which is an essential feature for low-speed rider comfort. The final machine design is experimentally validated via a full system prototype and dynamometer test facility. Results highlight some limitation of the 2-D finite element analysis (FEA) study in terms of the winding inductance calculation, more accurate 3-D FEA model is implemented.