gebhart/patrepeval huggingface dataset:
Metal [MLx; M = Fe, Cu, Co, Mn]/Hydroperoxide-Induced Activation of Dioxygen for the Oxygenation of Hydrocarbons:  Oxygenated Fenton Chemistry (1996)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMetal [MLx; M = Fe, Cu, Co, Mn]/Hydroperoxide-Induced Activation of Dioxygen for the Oxygenation of Hydrocarbons: Oxygenated Fenton ChemistryDonald T. Sawyer*Donald T. SawyerDepartment of Chemistry, Texas A&M University, College Station, Texas 77843 In papers with more than one author, the asterisk indicates the name of the author to whom inquiries about the paper should be addressed.More by Donald T. Sawyer, Andrzej SobkowiakAndrzej SobkowiakDepartment of Chemistry, Texas A&M University, College Station, Texas 77843 More by Andrzej Sobkowiak, and Takayuki MatsushitaTakayuki MatsushitaDepartment of Chemistry, Texas A&M University, College Station, Texas 77843 More by Takayuki MatsushitaCite this: Acc. Chem. Res. 1996, 29, 9, 409–416Publication Date (Web):September 11, 1996Publication History Received11 May 1995Published online11 September 1996Published inissue 11 September 1996https://pubs.acs.org/doi/10.1021/ar950031chttps://doi.org/10.1021/ar950031cresearch-articleACS PublicationsCopyright © 1996 American Chemical SocietyRequest reuse permissionsArticle Views2760Altmetric-Citations277LEARN 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 SUBJECTS:Hydrocarbons,Oxides,Reaction mechanisms,Reactivity,Reagents Get e-Alerts
Low voltage ride through control of a cascaded high power converter for direct-drive permanent magnet wind generators (2012)

Today's wind turbine power is approaching 5MW and above, where medium voltage power transfer is preferred for applications in such power range. This paper has identified three generator and converter topologies suitable for medium-voltage large wind turbines. In particular, the cascaded modular converter is investigated regarding the converter topology and control strategy with a focus on low voltage ride through (LVRT) capability. The generator-side rectifier can automatically reduce the generator output power during grid voltage drop through the dc-link voltage control loop. Hence, the converter cell dc-link voltage is maintained and the active power balance is achieved. The guideline to determine the rectifier control bandwidth and to predict the generator speed increase during grid fault is given in the paper. The grid-side cascaded H-bridge converter can generate reactive power as required to support the grid voltage during grid voltage drop and the active power output is limited by the current rating of power devices. A voltage-oriented vector control scheme allows independent regulation of the active and reactive power transferred to the grid. The phase-shifted PWM used for modulating the cascaded H-bridge converter may cause unintended active power flow into and out of individual power module, which could result in the dc-link over-voltage, especially when the converter only delivers reactive power to the grid as during the grid faults. The analytical expression of the active power flow due to the modulation is derived and a solution to avoid dc-link over-voltage is given. The simulation results of a 3.3kV, 3MW system has validated the proposed converter topology and control scheme for LVRT.
Unsupervised Pre-Training of Image Features on Non-Curated Data (2019)

Pre-training general-purpose visual features with convolutional neural networks without relying on annotations is a challenging and important task. Most recent efforts in unsupervised feature learning have focused on either small or highly curated datasets like ImageNet, whereas using uncurated raw datasets was found to decrease the feature quality when evaluated on a transfer task. Our goal is to bridge the performance gap between unsupervised methods trained on curated data, which are costly to obtain, and massive raw datasets that are easily available. To that effect, we propose a new unsupervised approach which leverages self-supervision and clustering to capture complementary statistics from large-scale data. We validate our approach on 96 million images from YFCC100M, achieving state-of-the-art results among unsupervised methods on standard benchmarks, which confirms the potential of unsupervised learning when only uncurated data are available. We also show that pre-training a supervised VGG-16 with our method achieves 74.9% top-1 classification accuracy on the validation set of ImageNet, which is an improvement of +0.8% over the same network trained from scratch. Our code is available at https://github.com/facebookresearch/DeeperCluster.
Field Electron Emission from Highly Graphitic Diamond Films with Ball-Like Surface Morphologies (1997)

Chemical vapor deposited diamond films with ball-like surface morphologies for field electron emission are reported on Mo substrates. A transparent conducting thin film anode (indium-tin oxide film coated on glass substrate) technique was used to determine the locations of field emission sites on the film cathode. The emission site density was obtained by counting damage spots on the film anode by optical microscopy. These damage spots, caused by the impact of emission electrons, corresponded to the emission sites. With the ball-like diamond films, a low turn-on filed of 2.1 V/μm and high current density of 4 mA/cm2 from an emitting area of 0.3 cm2 were obtained. A field enhancement model and injection mechanism have been developed to explain the low turn-on field and high emission current.
Grafting Slash Pine in the Field and in the Greenhouse (1955)

Abstract This experiment was designed to develop a suitable grafting technique for slash pine (Pinus elliottii Engelm.) as part of the forest genetics program. The techniques developed will be used in future breeding work to estimate the genotype of selected "plus" trees, to propagate selected trees and to establish seed orchards from superior parent stock. Various types and modifications of standard horticultural grafting methods have been tried with conifer forest species. It appears that special techniques have to be developed for the various species occurring in different climatic regions. A method which is successful in one climatic area may prove a complete failure in a region having different weather conditions. Such factors as time of grafting, age of stock, type of graft, and environment are extremely important if a large number of successful grafts are to be obtained. This study seeks to answer two questions. Is it physiologically feasible to graft slash pine scions? And which techniques are most efficient under north Florida conditions?
A Fully Autonomous Integrated Interface Circuit for Piezoelectric Harvesters (2012)

This paper presents a fully autonomous, adaptive pulsed synchronous charge extractor (PSCE) circuit optimized for piezoelectric harvesters (PEHs) which have a wide output voltage range 1.3-20 V. The PSCE chip fabricated in a 0.35 μm CMOS process is supplied exclusively by the buffer capacitor where the harvested energy is stored in. Due to the low power consumption, the chip can handle a minimum PEH output power of 5.7 μW. The system performs a startup from an uncharged buffer capacitor and operates in the adaptive mode at storage buffer voltages from 1.4 V to 5 V. By reducing the series resistance losses, the implementation of an improved switching technique increases the extracted power by up to 20% compared to the formerly presented Synchronous Electric Charge Extraction (SECE) technique and enables the chip efficiency to reach values of up to 85%. Compared to a low-voltage-drop passive full-wave rectifier, the PSCE chip increases the extracted power to 123% when the PEH is driven at resonance and to 206% at off-resonance.
Distributed weighted-multidimensional scaling for node localization in sensor networks (2006)

Accurate, distributed localization algorithms are needed for a wide variety of wireless sensor network applications. This article introduces a scalable, distributed weighted-multidimensional scaling (dwMDS) algorithm that adaptively emphasizes the most accurate range measurements and naturally accounts for communication constraints within the sensor network. Each node adaptively chooses a neighborhood of sensors, updates its position estimate by minimizing a local cost function and then passes this update to neighboring sensors. Derived bounds on communication requirements provide insight on the energy efficiency of the proposed distributed method versus a centralized approach. For received signal-strength (RSS) based range measurements, we demonstrate via simulation that location estimates are nearly unbiased with variance close to the Cramér-Rao lower bound. Further, RSS and time-of-arrival (TOA) channel measurements are used to demonstrate performance as good as the centralized maximum-likelihood estimator (MLE) in a real-world sensor network.
Identification of Human Glucocorticoid Receptor Complementary DNA Clones by Epitope Selection (1985)

Steroid hormones regulate cellular differentiation and physiologic functions predominantly through gene transcription. Regulation is achieved by the interaction of specific steroid receptor proteins and target genes. Expression cloning techniques were used to select human glucocorticoid receptor complementary DNA clones in order to define the mechanism by which the receptor exerts its transcriptional control. Immobilized fusion proteins from individual clones were used to select epitope-specific antibody which was subsequently eluted and identified by binding to protein blots of cellular extracts. Three cross-hybridizing clones containing inserts expressing antigenic determinants of the human glucocorticoid receptor were isolated.
Faecal tumour pyruvate kinase M2: not a good marker for the detection of colorectal adenomas (2008)

Faecal tumour pyruvate kinase M2: not a good marker for the detection of colorectal adenomas
The Molecular Mechanism of the Neutral-to-Base Transition of Human Serum Albumin (1989)

In order to obtain a better understanding of the neutral-to-base (N-B) transition of human serum albumin, we performed acid/base titration experiments and 500-MHz 1H NMR experiments on albumin and on a large peptic (residues 1-387) and large tryptic (residues 198-585) fragment of albumin. The acid/base titration experiments revealed that Ca2+ ions induce a downward pK shift of several histidine residues of the peptic (P46) fragment and of albumin. By contrast, Ca2+ has very little influence on the pK of histidine residues of the tryptic (T45) fragment. In albumin, the pH-dependent His C-2 proton resonances, observed with 1H NMR experiments, have been allotted the numbers 1-17. It proved possible to locate these resonances in the P46 and the T45 fragments. A correspondence was found between the number of histidines detected by the acid/base titration and by the 1H NMR experiments. The results of the experiments lead us to conclude that in domain 1 at least the histidines corresponding to the His C-2 proton resonances 1-5 play a dominant role in the N-B transition. The Cu2+-binding histidine residue 3 (resonance 8) of the albumin molecule is not involved in the N-B transition. In addition, we were able to assign His C-2 proton resonance 9 to histidine 464 of the albumin molecule. The role of the N-B transition in the transport and cellular uptake mechanisms of endogenous and exogenous compounds is discussed.
Gene program for cardiac cell survival induced by transient ischemia in conscious pigs (2001)

Therapy for ischemic heart disease has been directed traditionally at limiting cell necrosis. We determined by genome profiling whether ischemic myocardium can trigger a genetic program promoting cardiac cell survival, which would be a novel and potentially equally important mechanism of salvage. Although cardiac genomics is usually performed in rodents, we used a swine model of ischemia/reperfusion followed by ventricular dysfunction (stunning), which more closely resembles clinical conditions. Gene expression profiles were compared by subtractive hybridization between ischemic and normal tissue of the same hearts. About one-third (23/74) of the nuclear-encoded genes that were up-regulated in ischemic myocardium participate in survival mechanisms (inhibition of apoptosis, cytoprotection, cell growth, and stimulation of translation). The specificity of this response was confirmed by Northern blot and quantitative PCR. Unexpectedly, this program also included genes not previously described in cardiomyocytes. Up-regulation of survival genes was more profound in subendocardium over subepicardium, reflecting that this response in stunned myocardium was proportional to the severity of the ischemic insult. Thus, in a swine model that recapitulates human heart disease, nonlethal ischemia activates a genomic program of cell survival that relates to the time course of myocardial stunning and differs transmurally in relation to ischemic stress, which induced the stunning. Understanding the genes up-regulated during myocardial stunning, including those not previously described in the heart, and developing strategies that activate this program may open new avenues for therapy in ischemic heart disease.
Vaccine optimization for COVID-19, who to vaccinate first? (2020)

A vaccine, when available, will likely become our best tool to control the current COVID-19 pandemic. Even in the most optimistic scenarios, vaccine shortages will likely occur. Using an age-stratified mathematical model paired with optimization algorithms, we determined optimal vaccine allocation for four different metrics (deaths, symptomatic infections, and maximum non-ICU and ICU hospitalizations) under many scenarios. We find that a vaccine with effectiveness ≥50% would be enough to substantially mitigate the ongoing pandemic provided that a high percentage of the population is optimally vaccinated. When minimizing deaths, we find that for low vaccine effectiveness, irrespective of vaccination coverage, it is optimal to allocate vaccine to high-risk (older) age-groups first. In contrast, for higher vaccine effectiveness, there is a switch to allocate vaccine to high-transmission (younger) age-groups first for high vaccination coverage. While there are other societal and ethical considerations, this work can provide an evidence-based rationale for vaccine prioritization.
Affinity of fibronectin to collagens of different genetic types and to fibrinogen. (1978)

Fibronectin, a fibroblast surface protein, was purified from human and chicken plasma and extracts of cultured chicken fibroblasts with affinity chromatography on gelatin coupled to Sepharose particles. A fibronectin-like protein was also isolated from the plasma of Torpedo fish. The collagen binding properties of fibronectin were studied with several genetically distinct collagens. Heat denatured types I, II, and III collagens were equal in their binding capacity and more active than the native collagens or A and B chains. Native type III collagen was more active than the other native collagens. Human and chicken fibronectins showed approximately the same pattern of specificity. Identical specificities were shown by the plasma and fibroblast forms of chicken fibronectin. Two cyanogen bromide peptides of the collagen alpha1 (II) chain, CB8 and CB12, derived from different parts of the chain, were active in fibronectin binding. A polymer of the tripeptide pro-gly-pro, and polyproline were inactive. Fibronectin also binds to fibrinogen and fibrin. Comparison of this binding to collagen binding showed that fibrinogen inhibited binding of fibronectin to collagen, but was less active than native collagen. Two other fibrous proteins, tropoelastin and keratin, did not bind fibronectin. The binding of fibronectin to fibrinogen was inhibited by collagen and incorporation of fibronectin into blood clot in the cold was inhibited by gelatin. These results suggest that the binding of fibronectin to collagen and fibrinogen depends on the same binding site in the fibronectin molecule. It is proposed that cell surface fibronectin mediates attachment of cells to the collagenous extracellular matrix and to a temporary fibrin matrix in a wound.
Rapid generation of neutralizing antibody responses in COVID-19 patients (2020)

SARS-CoV-2 is currently causing a devastating pandemic and there is a pressing need to understand the dynamics, specificity, and neutralizing potency of the humoral immune response during acute infection. Herein, we report the dynamics of antibody responses to the receptor-binding domain (RBD) of the spike protein and virus neutralization activity in 44 COVID-19 patients. RBD-specific IgG responses were detectable in all patients 6 days after PCR confirmation. Using a clinical isolate of SARS-CoV-2, neutralizing antibody titers were also detectable in all patients 6 days after PCR confirmation. The magnitude of RBD-specific IgG binding titers correlated strongly with viral neutralization. In a clinical setting, the initial analysis of the dynamics of RBD-specific IgG titers was corroborated in a larger cohort of PCR-confirmed patients (n=231). These findings have important implications for our understanding of protective immunity against SARS-CoV-2, the use of immune plasma as a therapy, and the development of much-needed vaccines.
Hydrotropy: Monomer–Micelle Equilibrium and Minimum Hydrotrope Concentration (2014)

Drug molecules with low aqueous solubility can be solubilized by a class of cosolvents, known as hydrotropes. Their action has often been explained by an analogy with micelle formation, which exhibits critical micelle concentration (CMC). Indeed, hydrotropes also exhibit "minimum hydrotrope concentration" (MHC), a threshold concentration for solubilization. However, MHC is observed even for nonaggregating monomeric hydrotropes (such as urea); this raises questions over the validity of this analogy. Here we clarify the effect of micellization on hydrotropy, as well as the origin of MHC when micellization is not accompanied. On the basis of the rigorous Kirkwood-Buff (KB) theory of solutions, we show that (i) micellar hydrotropy is explained also from preferential drug-hydrotrope interaction; (ii) yet micelle formation reduces solubilization effeciency per hydrotrope molecule; (iii) MHC is caused by hydrotrope-hydrotrope self-association induced by the solute (drug) molecule; and (iv) MHC is prevented by hydrotrope self-aggregation in the bulk solution. We thus need a departure from the traditional view; the structure of hydrotrope-water mixture around the drug molecule, not the structure of the aqueous hydrotrope solutions in the bulk phase, is the true key toward understanding the origin of MHC.
Effect of some intranasal formulations used in the management of allergic rhinitis on mucociliary function (2015)

In the management of allergic rhinitis, drugs are delivered to the nasal cavity for a local effect. Mucociliary clearance (MC), the airway’s primary innate defense mechanism against inhaled foreign particles, clears the drug formulations and undesirably decreases their residence time. Certain formulation variables are hence designed to optimize the intranasal (IN) residence time. It is therefore important that the effect of IN formulations on MC is understood. MC is attained via ciliary input (cilia length and density and ciliary beat frequency (CBF)) and airway surface liquid (periciliary fluid underlying mucous blanket of optimum amount, depth and viscoelastic properties). In the present study, ovine ex-vivo models were used to investigate the effect of a number of anti-allergic IN formulations, by GlaxoSmithKline (GSK), on different components of MC, namely mucin secretion, CBF and mucociliary transport rate (MTR). In addition, the in-vitro cytotoxic effect of these formulations on the human bronchial epithelial cell line, 16HBE14o-, was examined using an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium-bromide) viability assay.
Mutant analysis of herpes simplex virus-induced cell surface antigens: resistance to complement-mediated immune cytolysis (1980)

BHK-21 cells infected with temperature-sensitive mutants of herpes simplex virus type 1 strain KOS representing 16 complementation groups were tested for susceptibility to complement-mediated immune cytolysis at permissive (34 degrees C) and nonpermissive (39 degrees C) temperatures. Only cells infected by mutants in complementation group E were resistant to immune cytolysis in a temperature-sensitive manner compared with wild-type infections. The expression of group E mutant cell surface antigens during infections at 34 and 39 degrees C was characterized by a combination of cell surface radioiodination, specific immunoprecipitation, and gel electrophoretic analysis of immunoprecipitates. Resistance to immune lysis at 39 degrees C correlated with the absence of viral antigens exposed at the cell surface. Intrinsic radiolabeling of group E mutant infections with [14C]glucosamine revealed that normal glycoproteins were produced at 34 degrees C but none were synthesized at 39 degrees C. The effect of 2-deoxy-D-glucose on glycosylation of group E mutants at 39 degrees C suggested that the viral glycoprotein precursors were not synthesized. The complementation group E mutants failed to complement herpes simplex virus type 1 mutants isolated by other workers. These included the group B mutants of strain KOS, the temperature-sensitive group D mutants of strain 17, and the LB2 mutant of strain HFEM. These mutants should be considered members of herpes simplex virus type 1 complementation group 1.2, in keeping with the new herpes simplex virus type 1 nomenclature.