gebhart/patrepeval huggingface dataset:
Inverse electron-demand Diels-Alder reactions of N-sulfonyl .alpha.,.beta.-unsaturated imines: a general approach to implementation of the 4.pi. participation of 1-aza-1,3-butadienes in Diels-Alder reactions (1991)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTInverse electron-demand Diels-Alder reactions of N-sulfonyl .alpha.,.beta.-unsaturated imines: a general approach to implementation of the 4.pi. participation of 1-aza-1,3-butadienes in Diels-Alder reactionsDale L. Boger, Wendy L. Corbett, Timothy T. Curran, and A. M. KasperCite this: J. Am. Chem. Soc. 1991, 113, 5, 1713–1729Publication Date (Print):February 1, 1991Publication History Published online1 May 2002Published inissue 1 February 1991https://pubs.acs.org/doi/10.1021/ja00005a040https://doi.org/10.1021/ja00005a040research-articleACS PublicationsRequest reuse permissionsArticle Views2390Altmetric-Citations186LEARN 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-AlertscloseSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts
Experimental evaluation of parameters of the capacitive MEMS converters (2009)

Parameters of the capacitive mechanical-to-electrical energy MEMS converters are investigated experimentally. A comparison of the theoretical calculations performed using simplified models as well as experimental data is carried out. The analysis shows that existing differences between calculated and experimental data are probably related to the additional factors, e.g. parasitic capacity, which arise during measurements and are not taken into considerations in the simplified models.
<i>H</i><sub>∞</sub>consensus control of multi-agent systems with switching topology: a dynamic output feedback protocol (2009)

Abstract This article is devoted to the consensus control for switching networks of multiple agents with linear coupling dynamics and subject to external disturbances, which is transformed into an H ∞ control problem by defining an appropriate controlled output. On this basis, a distributed dynamic output feedback protocol is proposed with an undetermined system matrix, and a condition in terms of linear matrix inequalities (LMIs) is derived to ensure consensus of the multi-agent system with a prescribed H ∞ level. Furthermore, system matrix of the protocol is designed by solving two LMIs. A numerical example is included to illustrate the effectiveness of the proposed consensus protocol. Keywords: consensusmulti-agent systems H ∞ controlexternal disturbancesswitching networks Acknowledgements This work is supported by the NSFC (60374001, 60727002, 60774003), the MOE (20030006003), the COSTIND (A2120061303) and the National 973 Program (2005CB321902).
Cleavage of Integral Surface Lipids of Wool by Aminolysis (1997)

A complex mixture of lipids is obtained upon treatment of wool with anhydrous alkylamines, with the major class being identified as N-alkylfalty amides (0.60 mg/g of extracted wool). Analysis of the lipids released by isopropylamine treatment shows that the major fatty amide is N-isopropyl-18-methyleicosanamide, which comprises 61% by weight of the total fatty amides released. Fatty acid hydroxamates (RCONHOH) are formed upon treatment of wool with anhydrous hydroxylamine. The alkyl hydroxamates (0.55 mg/g of extracted wool) are analyzed by HPLC, which again shows the 18-methyleieosanoic acid derivative to he the dominant species (71% by weight of the total fatty acid hydroxamates). These results indicate that the covalently bound fatty acids on the surface of wool may be readily cleaved by aminolysis with anhydrous alkylamines. I hey also support the hypothesis that the proteins within the cuticle cell membrane are acylated with fatty acids through a thioester linkage.
Workshop on global software development (2002)

The goal of this workshop is to bring together researchers and practitioners in trying to understand the emerging phenomenon of global software development. As we witness an increased globalization of software development, it is important that research addresses the challenges of distributed software engineering and informs the development of techniques and technologies to improve such practice.
Toward a Practical Data Privacy Scheme for a Distributed Implementation of the Smith-Waterman Genome Sequence Comparison Algorithm. (2006)

Volunteer distributed computations utilize spare processor cycles of personal computers that are connected to the Internet. The resulting platforms provide computational power previously available only through the use of expensive clusters or supercomputers. However, distributed computations running in untrustworthy environments raise a number of security concerns, including computation integrity and data privacy. This paper introduces a strategy for enhancing data privacy in some distributed volunteer computations, providing an important first step toward a general data privacy solution for these computations. The strategy is used to provide enhanced data privacy for the Smith-Waterman local nucleotide sequence comparison algorithm. Our modified Smith-Waterman algorithm provides reasonable performance, identifying most, and in many cases all, sequence pairs that exhibit statistically significant similarity according to the unmodified algorithm, with reasonable levels of false positives. Moreover the modified algorithm achieves a net decrease in execution time, with no increase in memory requirements. Most importantly, our scheme represents an important first step toward providing data privacy for a practical and important real-world algorithm.
Low-Rate Pipe Movement During Cement Gelation to Control Gas Migration and Improve Cement Bond (1991)

Abstract The traditional use of pipe movement was to enhance mud displacement, and there was little reason to continue movement after the cement slurry was in place. New technology has shown the rate and magnitude of the pressure loss during the cement gelation period has a major influence on cement job quality. A recently completed investigation using specialized laboratory equipment and large-scale models conclusively illustrates that low-rate rotation or reciprocation during the cement gelation period effectively delays the loss of pressure in the cement column. As movement was stopped during the test, resistance to fluid or gas migration in the annulus developed rapidly. Using gas migration terminology, this equates to a short transition time (&lt; 10 minutes). When compared to static conditions, pipe rotation continued to ≥ 500 lb/100 ft2 resulted in higher shear level and hydraulic bond. Torque needed for rotation was always lower than values calculated from static gel strength and was in the range for safe rotation without pipe thread failure.
Effect of Lactic Acid Bacteria on Diarrheal Diseases (2000)

Microbial balance is an important factor in the maintenance of intestinal homeostasis, and yogurt or fermented milk supplementation has been proposed to control diarrheal diseases. A number of studies using animal models and clinical studies in humans have confirmed the beneficial effect of such fermented products in case of lactose intolerance, viral diarrhea or antibiotics-associated diarrhea. The mechanisms by which lactic acid bacteria exert their effects are multiple. Bacterial lactase improves the absorption of lactose, but fermented products slow down the intestinal transit facilitating the action of residual intestinal lactase. The transient passage of lactic acid bacteria in the digestive tract may represent a microbial barrier against the development of pathogenic bacteria, probably due to the release of compounds contributing to the maintenance of colonization resistance to pathogens. The beneficial effects are mainly described in the presence of live bacteria, but inactivated bacteria may also present preventive or curative capacities in diarrheal diseases. Moreover, lactic acid bacteria has been described as reinforcing the non-specific immune defence but also specific immunity, particularly the secretory immune system mediated by secretory IgA or IgM in response to particulate infectious antigens and perhaps to soluble food antigens. Other possible mechanisms include the trophic effect on the intestinal layer, and a down-regulatory activity in cow's milk allergy as well as anti-inflammatory effects have also been suggested.
Heat Transfer Analysis of Plate-fin Heat Sink with Piezoelectric Fan (2015)

Applying software Ansys-Fluent to analysis the effect of piezoelectric fan device installed inside rectangular channel by numerical simulation method. The piezoelectric fan is activated by reversible piezoelectric effect in piezoelectric material, change rectangular channel flow field construction, then it affects heat flow status in advance. Numerical simulation parameter are included Nusselt number (N<sub>u</sub>), distance between peak of fan blades to front part of heat sink (L<sub>g</sub> =0, 5, 10, -11.25, -22.5, -33.75, -45), height from center on piezoelectric fan bottom side (H<sub>w</sub> =10, 16, 21), number of piezoelectric fan (single-fan and twin-fan), phase-shift (in-phase and counter-phase), and numbers (n=10, 14) for heat sink fin. This result is indicated that good position to temperature dropped greatly is located from the front part of piezoelectric fan to the front of heat sink (L<sub>g</sub> = -22.5) under fixes distance (H<sub>w</sub> = 21) from piezoelectric fan to channel also found to provide double piezoelectric fan heat drop effect is equal to single one, however, double piezoelectric fans would provide higher heat dissipation as Counter-phase. The performance of piezoelectric fan is improved depends on change height (H<sub>w</sub>) from center of piezoelectric fan to channel bottom; the height (H<sub>w</sub>) shall be decreased as piezoelectric fan placement at the front of heat sink.
CORROSION MONITORING OF PLUTONIUM OXIDE AND SNF (2003)

While developing a method to measure pressure in totally sealed stainless steel containers holding spent nuclear fuel at the U.S. DOE Hanford Site, Vista Engineering Technologies, LLC (Vista Engineering) personnel adapted the central concept to corrosion monitoring techniques for the same containers. The ability to monitor corrosion within vessels containing spent nuclear fuel, plutonium and other hazardous materials is imperative for safe storage. Vista Engineering personnel have devised a way to monitor corrosion in a totally sealed stainless steel container using a Magnetically Coupled Corrosion Gauge (MCCG) Patent Pending. The MCCG can be used to detect corrosion as well as measure corrosion rate and does not require any penetration of the containment vessel, which minimizes pressure boundary surface area and sensitive weld materials in the vessels.
Evaluating the effect of feedback from a CSCL problem solving environment on learning, interaction, and perceived interdependence (2007)

In this paper, we explore the effect of the form of feedback offered by a computer supported collaborative learning (CSCL) environment on the roles that students see themselves as taking and that their behavior reflects. We do this by experimentally contrasting collaboration in two feedback configurations, one which is identical to the state-of-the-art in intelligent tutoring technology (Immediate Feedback), and one which is based on a long line of investigation of the use of worked out examples for instruction (Delayed Feedback). While our conclusions remain tentative due to the small sample size, the data reveal a consistent gender by condition interaction pattern across questionnaire, test, and discourse data in which male students prefer and benefit more from collaboration in the Immediate Feedback condition where they are more likely to take on the role of a help provider rather than a help receiver while the patterns is the opposite for females.
Content based hidden web ranking algorithm(CHWRA) (2014)

The World Wide Web consists of millions of interconnected web pages that provide information to the user present in any part of the world. The World Wide Web is expanding and growing in size and the complexity of the web pages. That is why it is necessary to retrieve the best or the web pages that are more relevant in terms of information for the query entered by the user in the search engine. To extract the relevancy of a web page, the search engine requires applying retrieval or a ranking module that applies to a ranking algorithm on the web to fetch the web pages in order of the importance of the information entered by the user in the query. The ranking algorithm is much efficient to rank the surface web, i.e. the web pages that can be indexed by the search engine, as well as the hidden web, i.e. the web pages that cannot be indexed by the search engine. This Paper proposed an algorithm consists of: 1) PageRank Algorithm, 2) Term Weighting Technique, 3) Feedback (Likes/Dislikes) and 4) Visitor Count
Oxidative stability of seed oils extracted with supercritical carbon dioxide 1 (1989)

Abstract Dry‐milled corn germ, soybean and cottonseed flakes were extracted (at 70‐90 C and 12,000 psi) with supercritical carbon dioxide (SC‐CO 2 ) to yield crude oils. Oxidative stability of the crude oils was determined and compared to similar products obtained by conventional expeller and/or prepress solvent extraction. Under Schall oven storage conditions (60 C), SC‐CO 2 ‐extracted oils undergo rapid deterioration and fail to show the normal induction period observed with conventional expeller and solvent‐extracted crude oils. The levels of tocopherols found in SC‐CO 2 ‐extracted oils are comparable to those obtained by expeller or solvent extraction, while phospholipids present in significant amounts in conventional crude oils are essentially absent from SC‐CO 2 ‐processed crudes. The addition of phosphatides to SC‐CO 2 ‐extracted crude oils improves oxidative stability, which suggests that both tocopherols and phospholipids are required to stabilize crude oils against autoxidation. Heating of SC‐CO 2 ‐extracted crude oils to deodorization temperatures improves oxidative stability. The destruction of fat hydroperoxides under these conditions probably accounts for improved oxidative stability. A combination of heat and the addition of citric acid and phenolic antioxidants resulted in further improvement of oxidative stability.
Recognition of self and altered self by T cells in autoimmunity and allergy (2013)

T cell recognition of foreign peptide antigen and tolerance to self peptides is key to the proper function of the immune system. Usually, in the thymus T cells that recognize self MHC + self peptides are deleted and those with the potential to recognize self MHC + foreign peptides are selected to mature. However there are exceptions to these rules. Autoimmunity and allergy are two of the most common immune diseases that can be related to recognition of self. Many genes work together to lead to autoimmunity. Of those, particular MHC alleles are the most strongly associated, reflecting the key importance of MHC presentation of self peptides in autoimmunity. T cells specific for combinations of self MHC and self peptides may escape thymus deletion, and thus be able to drive autoimmunity, for several reasons: the relevant self peptide may be presented at low abundance in the thymus but at high level in particular peripheral tissues; the relevant self peptide may bind to MHC in an unusual register, not present in the thymus but apparent elsewhere; finally the relevant self peptide may be post translationally modified in a tissue specific fashion. In some types of allergy, the peptide + MHC combination may also be fully derived from self. However the combination in question may be modified by the presence of other ligands, such as small drug molecules or metal ions. Thus these types of allergies may act like the post translationally modified peptides involved some types of autoimmunity.
CARF and WYL domains: ligand-binding regulators of prokaryotic defense systems (2014)

CRISPR-Cas adaptive immunity systems of bacteria and archaea insert fragments of virus or plasmid DNA as spacer sequences into CRISPR repeat loci. Processed transcripts encompassing these spacers guide the cleavage of the cognate foreign DNA or RNA. Most CRISPR-Cas loci, in addition to recognized cas genes, also include genes that are not directly implicated in spacer acquisition, CRISPR transcript processing or interference. Here we comprehensively analyze sequences, structures and genomic neighborhoods of one of the most widespread groups of such genes that encode proteins containing a predicted nucleotide-binding domain with a Rossmann-like fold, which we denote CARF (CRISPR-associated Rossmann fold). Several CARF protein structures have been determined but functional characterization of these proteins is lacking. The CARF domain is most frequently combined with a C-terminal winged helix-turn-helix DNA-binding domain and "effector" domains most of which are predicted to possess DNase or RNase activity. Divergent CARF domains are also found in RtcR proteins, sigma-54 dependent regulators of the rtc RNA repair operon. CARF genes frequently co-occur with those coding for proteins containing the WYL domain with the Sm-like SH3 β-barrel fold, which is also predicted to bind ligands. CRISPR-Cas and possibly other defense systems are predicted to be transcriptionally regulated by multiple ligand-binding proteins containing WYL and CARF domains which sense modified nucleotides and nucleotide derivatives generated during virus infection. We hypothesize that CARF domains also transmit the signal from the bound ligand to the fused effector domains which attack either alien or self nucleic acids, resulting, respectively, in immunity complementing the CRISPR-Cas action or in dormancy/programmed cell death.
An active current-sensing constant-frequency HCC buck converter using phase-frequency-locked techniques (2008)

A hysteresis-current-controlled (HCC) buck converter with active current-sensing and phase-frequencylocked techniques is presented in this paper. The proposed active current-sensing technique can not only consume less power than previous techniques, but also fully sense the inductor current. Although the buck converter is HCC, the switching frequency can be constant due to the devised phase-frequency-locked technique. The proposed converter has been designed and implemented with TSMC 0.35 microm DPQM CMOS processes. It is shown in the experimental results that the HCC buck converter features the following characteristics: 1) up to 800 mA of load current, 2) wide input and output voltage range, 3) high power efficiency, and 4) constant-frequency operation.
<i>In vitro</i> chondrogenic commitment of human Wharton's jelly stem cells by co-culture with human articular chondrocytes (2015)

Wharton's jelly stem cells (WJSCs) are a potential source of transplantable stem cells in cartilage-regenerative strategies, due to their highly proliferative and multilineage differentiation capacity. We hypothesized that a non-direct co-culture system with human articular chondrocytes (hACs) could enhance the potential chondrogenic phenotype of hWJSCs during the expansion phase compared to those expanded in monoculture conditions. Primary hWJSCs were cultured in the bottom of a multiwell plate separated by a porous transwell membrane insert seeded with hACs. No statistically significant differences in hWJSCs duplication number were observed under either of the culture conditions during the expansion phase. hWJSCs under co-culture conditions show upregulations of collagen type I and II, COMP, TGFβ1 and aggrecan, as well as of the main cartilage transcription factor, SOX9, when compared to those cultured in the absence of chondrocytes. Chondrogenic differentiation of hWJSCs, previously expanded in co-culture and monoculture conditions, was evaluated for each cellular passage using the micromass culture model. Cells expanded in co-culture showed higher accumulation of glycosaminoglycans (GAGs) compared to cells in monoculture, and immunohistochemistry for localization of collagen type I revealed a strong detection signal when hWJSCs were expanded under monoculture conditions. In contrast, type II collagen was detected when cells were expanded under co-culture conditions, where numerous round-shaped cell clusters were observed. Using a micromass differentiation model, hWJSCs, previously exposed to soluble factors secreted by hACs, were able to express higher levels of chondrogenic genes with deposition of cartilage extracellular matrix components, suggesting their use as an alternative cell source for treating degenerated cartilage. Copyright © 2015 John Wiley & Sons, Ltd.
A Silicon Model Of Auditory Localization (1989)

The barn owl accurately localizes sounds in the azimuthal plane, using interaural time difference as a cue. The time-coding pathway in the owl's brainstem encodes a neural map of azimuth, by processing interaural timing information. We have built a silicon model of the time-coding pathway of the owl. The integrated circuit models the structure as well as the function of the pathway; most subcircuits in the chip have an anatomical correlate. The chip computes all outputs in real time, using analog, continuous-time processing.
Investigation of potential distribution on a CFRP coupon under impulse current. Test results and FDTD simulation (2016)

CFRP is becoming in an important material for the future blades due to alternative renewable energy industry plans to increase the length of the blades. This work shows some analytical results about potential distribution on a CFRP coupon obtained after applying an impulse current with different rise time. Effects around electrodes are, symmetry behavior and some interesting comments about the influence of the rise time appear. A FDTD simulation is done and a comparison between FDTD and analytical results. The aim is to evaluate how useful can be this technique when current distribution is over an anisotropic material since tests are not always possible.
Cyclobutadiene: The Antiaromatic Paradigm? (2006)

The heat of formation of cyclobutadiene has recently been determined by Kass and co-workers. This determination is taken as an occasion to reflect on the difficulty to extract from this number the “antiaromatic destabilization” and the strain energy of this most fundamental species.