gebhart/patrepeval huggingface dataset:
Highly Divergent Strains of Porcine Reproductive and Respiratory Syndrome Virus Incorporate Multiple Isoforms of Nonstructural Protein 2 into Virions (2013)

Viral structural proteins form the critical intermediary between viral infection cycles within and between hosts, function to initiate entry, participate in immediate early viral replication steps, and are major targets for the host adaptive immune response. We report the identification of nonstructural protein 2 (nsp2) as a novel structural component of the porcine reproductive and respiratory syndrome virus (PRRSV) particle. A set of custom α-nsp2 antibodies targeting conserved epitopes within four distinct regions of nsp2 (the PLP2 protease domain [OTU], the hypervariable domain [HV], the putative transmembrane domain [TM], and the C-terminal region [C]) were obtained commercially and validated in PRRSV-infected cells. Highly purified cell-free virions of several PRRSV strains were isolated through multiple rounds of differential density gradient centrifugation and analyzed by immunoelectron microscopy (IEM) and Western blot assays using the α-nsp2 antibodies. Purified viral preparations were found to contain pleomorphic, predominantly spherical virions of uniform size (57.9 nm ± 8.1 nm diameter; n = 50), consistent with the expected size of PRRSV particles. Analysis by IEM indicated the presence of nsp2 associated with the viral particle of diverse strains of PRRSV. Western blot analysis confirmed the presence of nsp2 in purified viral samples and revealed that multiple nsp2 isoforms were associated with the virion. Finally, a recombinant PRRSV genome containing a myc-tagged nsp2 was used to generate purified virus, and these particles were also shown to harbor myc-tagged nsp2 isoforms. Together, these data identify nsp2 as a virion-associated structural PRRSV protein and reveal that nsp2 exists in or on viral particles as multiple isoforms.
Thin base formation by double diffused polysilicon technology (2003)

The method of double-diffused emitter-base formation is characterized. It is shown to be a viable technique for the fabrication of advanced bipolar transistors. The use of amorphous instead of polycrystalline silicon as the emitter contact material results in a shallower emitter-base junction and little effect of the boron diffusion on the obtained arsenic profile. The narrowing of the base yields a higher intrinsic base resistance for the same number of carriers leading to a decrease in current gain for the same intrinsic base resistance. The different processing of double diffusion compared to base implantation may also lead to a loss in emitter efficiency. Nevertheless uniformity of the basewidth seems to be excellent and good high-frequency characteristics (up to f/sub T/=15 GHz) are obtained.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Soil Remediation Techniques at Uncontrolled Hazardous Waste Sites (1990)

The objective of this critical review is to address soil remediation techniques at uncontrolled hazardous waste sites with regard to the following areas: 1) important regulatory and technical issues and information needs concerning soil remediation at uncontrolled hazardous waste sites; 2) approaches for selection of remediation techniques; and 3) the current state of knowledge regarding soil remediation techniques, including applications and limitations. The areas identified above are addressed with regard to current information, selected milestone publications, and specific applications of technologies to provide a synthesis of the topic. The information concerning current issues, approaches, and soil remediation techniques presented was critically reviewed in order to: 1) identify deficiencies in current approaches; 2) develop a conceptual framework for remediation; and 3) recommend improved approaches for selection of remediation technologies.
Ethylene tetramerization with a highly active and long-lifetime trinuclear diphenylphosphinoamine/Cr(III)/MAO catalyst (2012)

The synthesis and characterization of a novel trinuclear diphosphinoamine ligand 2 are reported. The ligand combined with Cr(III), activated with methylaluminoxane, lead to highly active and long-lifetime catalytic systems for the tetramerization of ethylene to form 1-octene. The effects of reaction temperature, reaction pressure, molar ratio of Al/Cr and bis(diphenylphosphino)amine/Cr on the catalytic activity and product selectivity were studied. Compared with its mononuclear analogue 1, ligand 2 showed a higher catalytic activity and longer lifetime for ethylene tetramerization in the presence of methylaluminoxane as cocatalyst. High molecular weight polyethylene was generated as a by-product with extremely broad molecular weight distributions.
Synthesis and Evaluation of Novel Activated Mixed Carbonate Reagents for the Introduction of the 2-(Trimethylsilyl)ethoxycarbonyl(Teoc)-Protecting Group (1987)

The synthesis of 1-[2-(trimethylsilyl)ethoxycarbonyloxy]benzotriazole (Teoc-OBt) and 1-[2-(trimethylsilyl)ethoxycarbonyloxy]pyrrolidin-2,5-dione (Teoc-OSu) in high yields is reported. Both compounds are crystalline compounds that react with amino acids under Schotten-Baumann conditions to produce Teoc-amino acids in high yields. The synthesis of nine new Teoc-amino acid derivatives is reported. Analysis of the products obtained during the synthesis of Teoc-Phe before and after crystallization as the cyclohexylamine salt revealed that ~ 5% of the corresponding dipeptide, Teoc-Phe-Phe-OH was produced when Teoc-OBt was used as the acylating reagent. In contrast, no dipeptide was detected when Teoc-OSu was utilized as the acylating reagent for the synthesis of the Teoc-amino acid derivatives studied. The use of Teoc-OSu should facilitate the use of the Teoc-group in peptide synthesis.
Reverse Sample Genome Probing, a New Technique for Identification of Bacteria in Environmental Samples by DNA Hybridization, and Its Application to the Identification of Sulfate-Reducing Bacteria in Oil Field Samples (1991)

A novel method for the identification of bacteria in environmental samples by DNA hybridization is presented. It is based on the fact that, even within a genus, the genomes of different bacteria may have little overall sequence homology. This allows the use of the labeled genomic DNA of a given bacterium (referred to as a “standard”) to probe for its presence and that of bacteria with highly homologous genomes in total DNA obtained from an environmental sample. Alternatively, total DNA extracted from the sample can be labeled and used to probe filters on which denatured chromosomal DNA from relevant bacterial standards has been spotted. The latter technique is referred to as reverse sample genome probing, since it is the reverse of the usual practice of deriving probes from reference bacteria for analyzing a DNA sample. Reverse sample genome probing allows identification of bacteria in a sample in a single step once a master filter with suitable standards has been developed. Application of reverse sample genome probing to the identification of sulfate-reducing bacteria in 31 samples obtained primarily from oil fields in the province of Alberta has indicated that there are at least 20 genotypically different sulfate-reducing bacteria in these samples.
Synthesis of Glycoglycerolipids: 3-<i>O</i>-Mannooligosyl-l,2-di-<i>O</i>-tetradecyl-<i>sn</i>-glycerol (1982)

Synthetic routes for the following mannooligosylglycerolipids of biological interest were developed by using regioselectively protected monosaccharide synthons and l,2-di-O-alkyl-sn-glycerol; 3-O-(2-O-α-D-mannopyranosyl-α-D-mannopyranosyl)-l,2-di-O-tetradecyl-sn-glycerol; 3-O-[2-O-(2-O-α-D-mannopyranosyl-α-D-mannopyranosyl)-α-D-mannopyranosyl]-l,2-di-O-tetradecyl-sn-glycerol; 3-O-(6-O-α-D-mannopyranosyl-α-D-mannopyranosyl)-l,2-di-O-tetradecyl-sn-glycerol; and 3-O-(3,6-di-O-α-D-mannopyranosyl-α-D-mannopyranosyl)-1,2-di-α-tetradecyl-sn-glycerol.
Extracting search-focused key n-grams for relevance ranking in web search (2012)

In web search, relevance ranking of popular pages is relatively easy, because of the inclusion of strong signals such as anchor text and search log data. In contrast, with less popular pages, relevance ranking becomes very challenging due to a lack of information. In this paper the former is referred to as head pages, and the latter tail pages. We address the challenge by learning a model that can extract search-focused key n-grams from web pages, and using the key n-grams for searches of the pages, particularly, the tail pages. To the best of our knowledge, this problem has not been previously studied. Our approach has four characteristics. First, key n-grams are search-focused in the sense that they are defined as those which can compose "good queries" for searching the page. Second, key n-grams are learned in a relative sense using learning to rank techniques. Third, key n-grams are learned using search log data, such that the characteristics of key n-grams in the search log data, particularly in the heads; can be applied to the other data, particularly to the tails. Fourth, the extracted key n-grams are used as features of the relevance ranking model also trained with learning to rank techniques. Experiments validate the effectiveness of the proposed approach with large-scale web search datasets. The results show that our approach can significantly improve relevance ranking performance on both heads and tails; and particularly tails, compared with baseline approaches. Characteristics of our approach have also been fully investigated through comprehensive experiments.
12% Efficiency CuIn(Se,S)<sub>2</sub>Photovoltaic Device Prepared Using a Hydrazine Solution Process (2009)

Thin-film CuIn(Se,S)2 (i.e., CIS) absorbers have been solution-deposited using a hydrazine-based approach that offers the potential to significantly lower the fabrication cost for CIS solar cells. In this method, metal chalcogenides are completely dissolved in hydrazine, forming a homogeneous precursor solution. Film deposition is demonstrated by spin-coating of the precursor solution onto various substrates, including Mo-coated glass and thermally oxidized silicon wafers. Using this approach, no postdeposition anneal in a toxic Se or S-containing environment is needed to obtain CIS films. Instead, only a simple heat-treatment in an inert atmosphere is required, resulting in CIS films with good crystallinity. Bandgap tuning can readily be achieved by varying the amount of S incorporated into the film. Complete CIS devices with glass/Mo/CIS/CdS/i-ZnO/ITO structure are fabricated using absorbers produced via this hydrazine-based approach. Air Mass 1.5G power conversion efficiencies of as high as 12.2% have been achieved, demonstrating that this new approach has great potential as a low-cost alternative for high-efficiency CIS solar cell production.
Monitoring Web information changes (2002)

Often Web users want to be notified when specific information contained in a Web page has been modified. The problem of detecting Web document changes has been deeply investigated and several systems providing notification of Web page changes are available. These systems do not provide notification of changes on specific information contained in a Web page. In this work we present a system called CDWeb that performs this task. It allows users to monitor a whole document or specific portions of it. Users can also specify what kind of changes they are interested in, such as structural changes, or semantic changes. The system provides a flexible and adaptive view of the Web: it tracks user queries and creates user profiles, in order to associate a personalized view to each user.
Tuning and chirping fiber Bragg gratings by deep etching (1995)

We have demonstrated a new method for tuning and chirping fiber gratings. It relies on etching of a fiber down to very small cladding diameter, so that the propagating optical mode in the fiber interacts with the surrounding media. A tuning range of 4.5 nm has been demonstrated with a potential of much larger tuning range by optimization of fibers. Chirped gratings were also demonstrated with this technique. These chirped gratings are very important for use in fiber dispersion compensation and optical pulse shaping.
Peptide Photodissociation with 157 nm Light in a Commercial Tandem Time-of-Flight Mass Spectrometer (2009)

Photodissociation with 157 nm light was implemented in an ABI model 4700 matrix-assisted laser desorption ionization (MALDI) tandem time-of-flight (TOF) mass spectrometer for peptide analysis. With a homemade computer program to control the light timing based on the m/z of each precursor ion, the photodissociation setup was seamlessly automated with the mass spectrometer. Peptide photodissociation in this apparatus yielded fragments similar to those observed in previous experiments with a home-built tandem-TOF mass spectrometer. Peptides having arginine at their C-termini yielded high-energy x-, v-, and w- type fragments, while peptides with N-terminal arginine produced many a- and d- type ions. Abundant immonium ions were also generated. High-quality photodissociation spectra were obtained with as little as 5 fmol of peptides. In the analysis of various tryptic peptides, photodissociation provided much more sequence information than the conventional TOF-TOF collision induced dissociation (CID). Because of the high fragmentation efficiency, sensitivity was not sacrificed to achieve this.
[Close reduction by Chinese traditional manipulation and MIPPO for the treatment of tibial fractures in middle and distal segment]. (2012)

Close manipulative reduction and MIPPO fixation is a good method for the treatment of the tibial fractures in the middle and distal segment.
A Synthetic DNA Walker for Molecular Transport (2004)

Inspired by kinesin movement along a microtubule, we demonstrate a processive bipedal DNA walker. Powered by externally controlled DNA fuel strands, the walker locomotes with a 5 nm stride by advancing the trailing foot to the lead at each step. Real-time monitoring of specific bidirectional walker movement is achieved via multiplexed fluorescence quenching.
A New N-Terminal Blocking Group Involving a Schiff Base in Hemoglobin A<sub>Ic</sub><sup>*</sup> (1966)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTA New N-Terminal Blocking Group Involving a Schiff Base in Hemoglobin AIc*W. R. Holmquist and W. A. SchroederCite this: Biochemistry 1966, 5, 8, 2489–2503Publication Date (Print):August 1, 1966Publication History Published online1 May 2002Published inissue 1 August 1966https://doi.org/10.1021/bi00872a002RIGHTS & PERMISSIONSArticle Views335Altmetric-Citations139LEARN 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 InReddit PDF (2 MB) Get e-Alerts Get e-Alerts
Vapour phase hydrogenolysis of biomass‐derived diethyl succinate to tetrahydrofuran over CuOZnO/solid acid bifunctional catalysts (2010)

Abstract BACKGROUND: Catalytic upgrading of fermentation‐derived succinic acid or its derivates (succinic acid esters and succinic anhydride) to value added chemicals has received great attention recently. The aim of this work is to provide a process for the production of tetrahydrofuran from succinic acid esters. RESULTS: The hydrogenolysis of biomass‐derived diethyl succinate was investigated over CuOZnO and CuOZnO/solid acid (HY, HZSM‐5, SAPO‐11 and Al 2 O 3 ) catalysts in a fixed‐bed reactor. Over CuOZnO, gamma ‐butyrolactone and 1,4‐butanediol can be selectively produced under appropriate reaction conditions, while the selectivity of tetrahydrofuran is relatively low due to the weak acidity of CuOZnO. Over CuOZnO/HZSM, both the formed 1,4‐butanediol and ethanol can be further converted to tetrahydrofuran and diethyl ether, while tetrahydrofuran is selectively produced over CuOZnO/HY. CuOZnO/Al 2 O 3 and CuOZnO/SAPO exhibit slight improvements in terms of selectivity to tetrahydrofuran when compared with CuOZnO. CONCLUSION: CuOZnO/HY is an appropriate catalyst to produce tetrahydrofuran from biomass‐derived diethyl succinate with high activity, selectivity and stability. Furthermore, Brønsted acid sites with appropriate acid strength are responsible for the selective formation of tetrahydrofuran under the applied reaction conditions. Copyright © 2010 Society of Chemical Industry
VPA‐induced neural tube defects in mice. I. altered metabolism of sulfur amino acids and glutathione (1998)

Valproate (VPA) has been shown to induce neural tube defects (NTDs) in humans and mice, but the mechanism of action has not been elucidated. Folate supplementation has been reported to prevent the defect. It was the aim of our experiment to reveal effects of VPA and of folate coadministration on amino acid metabolism in an NTD mouse model. After treating pregnant mice intraperitoneally with 2.1 mmol VPA/kg body weight, plasma homocysteine concentrations were found to be increased. Coadministration of 4 mg/kg folate decreased this level. Plasma methionine levels were reduced under both experimental conditions. Fifteen min after treating mice with 3 mmol VPA/kg body weight, hepatic levels of both S-adenosylmethionine (SAM) and S-adenosylhomocysteine were found to be increased by +175% and +348%, respectively; but the levels had normalized again 30 min after VPA injection. Simultaneously, plasma methionine and serine levels had decreased by –43% and –51%, respectively, while homocysteine and cysteine increased by +71% and +81%, respectively. Reduced glutathione (GSH) decreased by –45%, but total glutathione did not change. These changes were statistically significant, and they occurred dose-dependently. We proposed that VPA induces methionine deficiency, inhibition of folate metabolism and homocysteine remethylation, increase in aminothiols, and suppression of the GSH system in maternal blood within 1 h after application. These changes may be responsible for the teratogenic potential of VPA. Folate may prevent NTDs by changing homocysteine catabolism. Teratogenesis Carcinog. Mutagen. 18:49–61, 1998. © 1998 Wiley-Liss, Inc.
Application of tunable diode laser absorption for trace stratospheric measurements of HCl: laboratory results (1984)

In this paper we report the results of a laboratory study for detecting the important atmospheric molecule HCl using a tunable diode laser coupled to a multipass White cell. In contrast to many such prototype studies, the calibration in this work was carried out near the concentration range of interest and verified using three different techniques. Employing a 40-m path length, we have demonstrated a detection limit (SNR = 1) in the 150–230 parts-per-trillion range at pressures around 9 Torr.
107 Gb/s coherent optical OFDM transmission over 1000-km SSMF fiber using orthogonal band multiplexing (2008)

Coherent optical OFDM (CO-OFDM) has emerged as an attractive modulation format for the forthcoming 100 Gb/s Ethernet. However, even the spectral-efficient implementation of CO-OFDM requires digital-to-analog converters (DAC) and analog-to-digital converters (ADC) to operate at the bandwidth which may not be available today or may not be cost-effective. In order to resolve the electronic bandwidth bottleneck associated with DAC/ADC devices, we propose and elucidate the principle of orthogonal-band-multiplexed OFDM (OBM-OFDM) to subdivide the entire OFDM spectrum into multiple orthogonal bands. With this scheme, the DAC/ADCs do not need to operate at extremely high sampling rate. The corresponding mapping to the mixed-signal integrated circuit (IC) design is also revealed. Additionally, we show the proof-of-concept transmission experiment through optical realization of OBM-OFDM. To the best of our knowledge, we present the first experimental demonstration of 107 Gb/s QPSK-encoded CO-OFDM signal transmission over 1000 km standard-single- mode-fiber (SSMF) without optical dispersion compensation and without Raman amplification. The demonstrated system employs 2x2 MIMO-OFDM signal processing and achieves high electrical spectral efficiency with direct-conversion at both transmitter and receiver.
Optimizing agent behavior over long time scales by transporting value (2019)

Humans prolifically engage in mental time travel. We dwell on past actions and experience satisfaction or regret. More than storytelling, these recollections change how we act in the future and endow us with a computationally important ability to link actions and consequences across spans of time, which helps address the problem of long-term credit assignment: the question of how to evaluate the utility of actions within a long-duration behavioral sequence. Existing approaches to credit assignment in AI cannot solve tasks with long delays between actions and consequences. Here, we introduce a paradigm where agents use recall of specific memories to credit past actions, allowing them to solve problems that are intractable for existing algorithms. This paradigm broadens the scope of problems that can be investigated in AI and offers a mechanistic account of behaviors that may inspire models in neuroscience, psychology, and behavioral economics.
Control of Active Suspension System by Using H ∞ Theory (2000)

Automotive suspension systems have considerable importance in vehicle design. The designed suspension must provides for a trade-off between several competing objectives: passenger comfort, small suspension stroke for packing, and small tire deflection for vehicle handling. The passenger comfort index is judged by the acceleration of the car body. The next ones are suspension and tire deflection indices. They usually consist of a spring and a damper. With only mechanical construction, the passive suspension systems have their limit properties. In the interest of H controller, three interest transfer functions from road disturbance to car body acceleration, suspension deflection, and tire deflection are plotted: the plotted results are compared to the passive case to show the effectiveness of H controller. In the experimental apparatus, the road disturbance is generated by a cam shaft. By changing the revolution of cam shaft, the road disturbances are given with different frequencies. Measuring the suspension deflection, tire deflection and calculating the car body acceleration from measured car body displacement, then we can derive the gains of three interest transfer functions. These transfer functions are plotted to verify the simulation results. The results showed us that H controller reduces considerably the gains of three interest transfer functions at frequency region around 1 Hz. Abstract : This paper presents a control of active suspension for quarter car model with two degree of freedom by using H∞ method. Absolute velocity of car body is measured for feedback. The system parameter variations are treated with multiplicative uncertainty model. Simulation results show that the H∞controller provides good trade-off between ride quality, suspension packaging and road holding constraints. The experiment with a front wheel suspension system was done to verify the simulation results.