gebhart/patrepeval huggingface dataset:
Polyisobutylene-Based Diols and Polyurethanes (1981)

A novel polyisobutylene-based diol has been synthesized and subsequently used in conjunction with tolylene diisocyanate (TDI) to yield polyurethanes. The diol was obtained by quantitative hydroboration/oxidation from the corresponding telechelic diolefin which in turn was prepared by quantitative dehydrochloration of the corresponding dichloride (Scheme I). The number average functionality of the diol is exactly two and its molecular weight polydispersity is 1.5. Extension of telechelic polyisobutylene diols (Mn = 1,700-3,000) with TDI (NCO/OH = 1.0, bulk, 80°, two days) yielded a 5.5-8.7 fold increase in molecular weight. The products are strong rubbers exhibiting rapid recovery upon releasing the strain of stretching. The Tg's of polyurethanes prepared in the absence (PU-1) and presence of 1,4-butanediol (PU-2) extender have been determined. DSC showed two transitions, at-64° and 81°C for PU-1 and -61° and 93° for PU-2. The first transition is due to rubbery polyisobutylene domains while the second to hard TDI domains. 1 DSC traces of HO-CH2-PIB-CH2-OH, PU-1, and PU-2.
Bone mineral density at the femur and lumbar spine in a population of young women treated for scoliosis in adolescence. (1999)

These findings suggest a need for osteopenia screening and prevention in children with scoliosis, for monitoring physical activity and calcium intake during bracing, for preferring braces that allow greater mobility, and for closely monitoring the scoliosis during adulthood if osteopenia is present.
Nuclear localization and regulation of erk- and rsk-encoded protein kinases. (1992)

We demonstrate that members of the erk-encoded family of mitogen-activated protein (MAP) kinases (pp44/42mapk/erk) and members of the rsk-encoded protein kinases (RSKs or pp90rsk) are present in the cytoplasm and nucleus of HeLa cells. Addition of growth factors to serum-deprived cells results in increased tyrosine and threonine phosphorylation and in the activation of cytosolic and nuclear MAP kinases. Activated MAP kinases then phosphorylate (serine/threonine) and activate RSKs. Concurrently, a fraction of the activated MAP kinases and RSKs enter the nucleus. In addition, a distinct growth-regulated RSK-kinase activity (an enzyme[s] that phosphorylates recombinant RSK in vitro and that may be another member of the erk-encoded family of MAP kinases) was found associated with a postnuclear membrane fraction. Regulation of nuclear MAP kinase and RSK activities by growth factors and phorbol ester is coordinate with immediate-early gene expression. Indeed, in vitro, MAP kinase and/or RSK phosphorylates histone H3 and the recombinant c-Fos and c-Jun polypeptides, transcription factors phosphorylated in a variety of cells in response to growth stimuli. These in vitro studies raise the possibility that the MAP kinase/RSK signal transduction pathway represents a protein-Tyr/Ser/Thr phosphorylation cascade with the spatial distribution and temporal regulation that can account for the rapid transmission of growth-regulating information from the membrane, through the cytoplasm, and to the nucleus.
The Gamma database machine project (1990)

The design of the Gamma database machine and the techniques employed in its implementation are described. Gamma is a relational database machine currently operating on an Intel iPSC/2 hypercube with 32 processors and 32 disk drives. Gamma employs three key technical ideas which enable the architecture to be scaled to hundreds of processors. First, all relations are horizontally partitioned across multiple disk drives, enabling relations to be scanned in parallel. Second, parallel algorithms based on hashing are used to implement the complex relational operators, such as join and aggregate functions. Third, dataflow scheduling techniques are used to coordinate multioperator queries. By using these techniques, it is possible to control the execution of very complex queries with minimal coordination. The design of the Gamma software is described and a thorough performance evaluation of the iPSC/s hypercube version of Gamma is presented.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>
Dual isotope myocardial perfusion SPECT in the detection of coronary artery disease: comparison of separate and simultaneous acquisition protocols. (1993)

A time-saving dual isotope acquisition protocol was carried out for the simultaneous assessment of stress and rest myocardial perfusion, and the diagnostic value of the technique was evaluated using coronary angiography results as a reference. Fifty-five patients undergoing coronary angiography before surgery were included in the study. Stress tests were applied, either with a treadmill (25 patients) or dobutamine infusion (30 patients in 5-40 micrograms/kg/min doses). All patients received 3 mCi of thallium-201 at rest. Stress tests were applied 30 minutes later, and at peak stress 7 mCi of 99mTc-MIBI was administered. A dual isotope SPECT study was carried out one hour after the administration of 99mTc-MIBI. Tracer doses were optimised with phantom studies, and the down-scatter of each radioisotope on the other data was investigated. In 30 patients, 10 minutes after the 201Tl injection a separate rest 201Tl acquisition was also performed, to compare the data with dual acquisition. 201Tl rest imaging SPECT data was evaluated by segmental analysis according to coronary artery regions. In 55% of the segments stress defects were observed. Similar results were obtained for the detection of defect reversibility; i.e. stress MIBI/rest 201Tl (75%) and stress MIBI/simultaneous 201Tl (78%). The overall sensitivity and specificity of simultaneous dual isotope SPECT with respect to coronary angiography results were 88% and 84%, respectively. A good correlation and no significant difference was observed between the two acquisition methods. However, the simultaneous acquisition protocol has many advantages, i.e. halving the acquisition time, shortening the overall decision-making time, and decreasing unmatched stress-rest artifacts.
Relationship of resistance to oxygen free radicals to CuZn‐superoxide dismutase activity in transgenic, transfected, and trisomic cells (1992)

Although CuZn-superoxide dismutase (CuZnSOD) has been shown to reduce oxidative damage in several systems, the quantitative relationship between the degree of protection and CuZnSOD activity has not been well investigated. Therefore, the ability of cells to tolerate superoxide toxicity was assessed as a function of endogenous CuZnSOD activity in several mouse and human cell lines with progressively higher levels of CuZnSOD activity. In five lines of fetal fibroblasts derived from SOD1-transgenic mice, with CuZnSOD activities of 1.7- to 7.1-fold the nontransgenic level and no changes in the cellular glutathione peroxidase (GSHPx) activity, a direct relationship (r = 0.97) between the LD50 to paraquat and enzyme activity was observed, suggesting that CuZnSOD activity is the single most important factor in determining the paraquat LD50. Mouse trisomy 16 fetal fibroblasts and human trisomy 21 lung fibroblasts, both expressing a 1.5-fold increase in CuZnSOD activity, were 1.5-fold more tolerant to paraquat than were their diploid counterparts. Furthermore, the protective effect of CuZnSOD at the DNA level, as shown by reduced thymine glycol generation, was demonstrated in paraquat-treated transgenic fibroblasts. A direct relationship (r = 0.78) of paraquat LD50 and CuZnSOD activity was also observed with a panel of six lines of SOD1- transfected HeLa cells with 1.6- to 7.3-fold the basal CuZnSOD activity. Moreover, there was no correlation between resistance to paraquat toxicity and the cellular GSHPx and/or catalase activity. Taken together, these results demonstrate a consistently protective effect of endogenous CuZnSOD against superoxide toxicity in both primary and transformed cell lines.
Cyclosporin A as Immunosuppressive Treatment Option for Patients with Refractory Auto-Immune Thrombocytopenic Purpura. (2004)

Abstract The treatment of auto-immune thrombocytopenic purpura (AITP) remains unsatisfactory in patients refractory to first-line management such as corticosteroids and/or splenectomy. Those patients usually require unacceptably high doses of corticosteroids to maintain a safe platelet count and thus have refractory AITP. Relativelly new immunosupressive treatment modality is cyclosporin A (CsA) and no large studies involving these drug have been conducted. We treated 7 refractory AITP patients with CsA. Their platelet count were without any therapy below 20x109/L and mostly they had signs of subcutaneous and mucosal bleeding. In 6/7 patients splenectomy was performed earlier. In order to maintain »safe« platelet count, they all needed methylprednisolon (MP), at least 32 mg/daily. So at the time treatment with CsA began, all patients were on MP. During next months MP dosage was tapered or withdrew, according to patients platelet count and treatment efficacy. At the endpoint, in 4/7 patients complete remission (CR) was achieved and later CsA was slowly ceased. 3/7 patients are currently in partial remission (PR) of the disease. Also one of them who has more than 30 years history of the disease is in stable PR, on low dose CsA and low dose MP maintanance therapy. Her platelet count is well above 20x109/L. Among CsA treatment related side effects painful lower limb edema was most frequent. Based on our experience we suggest, that CsA should be recommended in refractory (chronic) AITP patients, because it shows long-term efficacy and good safety profile and is able to sustain remission at low doses or even after CsA discontinuation.
Environment of the Active Site Region of RseP, an Escherichia coli Regulated Intramembrane Proteolysis Protease, Assessed by Site-directed Cysteine Alkylation (2006)

Regulated intramembrane proteolysis (RIP) plays crucial roles in both prokaryotic and eukaryotic organisms. Proteases for RIP cleave transmembrane regions of substrate membrane proteins. However, the molecular mechanisms for the proteolysis of membrane-embedded transmembrane sequences are largely unknown. Here we studied the environment surrounding the active site region of RseP, an Escherichia coli S2P ortholog involved in the sigma(E) pathway of extracytoplasmic stress responses. RseP has two presumed active site motifs, HEXXH and LDG, located in membrane-cytoplasm boundary regions. We examined the reactivity of cysteine residues introduced within or in the vicinity of these two active site motifs with membrane-impermeable thiol-alkylating reagents under various conditions. The active site positions were inaccessible to the reagents in the native state, but many of them became partially modifiable in the presence of a chaotrope, while requiring simultaneous addition of a chaotrope and a detergent for full modification. These results suggest that the active site of RseP is not totally embedded in the lipid phase but located within a proteinaceous structure that is partially exposed to the aqueous milieu.
Isolation and Identification of Diacylglyceryl-<italic>O</italic>-4′-(<italic>N,N,N</italic>-trimethyl)-homoserine from the Fern <italic>Adiantum capillus-veneris</italic> L. (1983)

Diacylglyceryl-O-4′-(N,N,N-trimethyl)-homoserine was isolated from fronds of the fern Adiantum capillus-veneris L. and identified by chemical and spectral analyses. Positional analysis of the fatty acids by lipase treatment showed that palmitic acid was esterified at position 1, but linoleic, linolenic and arachidonic acids at position 2 of the glycerol moiety of the lipid. Although the trimethylhomoserine lipid has been found in some algal species, this is the first report that it exists in a vascular plant.
Assessment of Cavitation Erosion With a URANS Method (2013)

An assessment of the cavitation erosion risk by using a contemporary unsteady Reynolds-averaged Navier–Stokes (URANS) method in conjunction with a newly developed postprocessing procedure is made for an NACA0015 hydrofoil and an NACA0018-45 hydrofoil, without the necessity to compute the details of the actual collapses. This procedure is developed from detailed investigations on the flow over a hydrofoil. It is observed that the large-scale structures and typical unsteady dynamics predicted by the URANS method with the modified shear stress transport (SST) k-ω turbulence model are in fair agreement with the experimental observations. An erosion intensity function for the assessment of the risk of cavitation erosion on the surface of hydrofoils by using unsteady RANS simulations as input is proposed, based on the mean value of the time derivative of the local pressure that exceeds a certain threshold. A good correlation is found between the locations with a computed high erosion risk and the damage area observed from paint tests.
The effects of additive solution pH and metabolic rejuvenation on anaerobic storage of red cells (2008)

Extended RBC storage may be achieved using anaerobic conditions combined with low-pH AS and rejuvenation during storage.
Placental Hofbauer cells limit HIV-1 replication and potentially offset mother to child transmission (MTCT) by induction of immunoregulatory cytokines (2012)

HCs have reduced ability to replicate and disseminate R5-tropic HIV-1BaLin vitro and potentially offset mother to child transmission (MTCT) of HIV-1 by the induction of immunoregulatory cytokines. Despite the potential for migration and infectivity, HCs are not present in the neighboring fetal circulation. These results implicate HCs as important mediators of protection at the feto-maternal interface during ongoing HIV-1 exposure.
Defibrination with Ancrod in Glomerulonephritis: Effects on Clinical and Histologic Findings and on Blood Coagulation (1982)

Ancrod, which produces in vivo defibrination, has been shown to improve renal function and decrease fibrin deposition and crescents in experimental glomerulonephritis. Ancrod was given for 14 days to 5 patients with glomerulonephritis, moderate to severe renal functional impairment, crescents, and/or fibrin deposition in glomeruli. 4 patients had systemic lupus erythematosus. Ancrod treatment resulted in fibrinogen levels less than 50 mg/dl without bleeding, decrease of previously elevated factor VIII and von Willebrand factor levels, and normalization of in vitro platelet hyperaggregation. Renal function improved in all 5 patients. Serial renal biopsies showed a relatively rapid decrease of glomerular thrombi and necrosis and little increase in glomerular sclerosis. Ancrod administration appears safe, and may have a role in treatment of certain types of glomerulonephritis.
Coding-Sequence Determinants of Gene Expression in Escherichia coli (2009)

Synonymous mutations do not alter the encoded protein, but they can influence gene expression. To investigate how, we engineered a synthetic library of 154 genes that varied randomly at synonymous sites, but all encoded the same green fluorescent protein (GFP). When expressed in Escherichia coli, GFP protein levels varied 250-fold across the library. GFP messenger RNA (mRNA) levels, mRNA degradation patterns, and bacterial growth rates also varied, but codon bias did not correlate with gene expression. Rather, the stability of mRNA folding near the ribosomal binding site explained more than half the variation in protein levels. In our analysis, mRNA folding and associated rates of translation initiation play a predominant role in shaping expression levels of individual genes, whereas codon bias influences global translation efficiency and cellular fitness.
Artificial bandwidth extension of speech signals using MMSE estimation based on a hidden Markov model (2003)

We present an algorithm to derive 7 kHz wideband speech from narrowband "telephone speech". A statistical approach is used that is based on a hidden Markov model (HMM) of the speech production process. A new method for the estimation of the wideband spectral envelope is proposed, using nonlinear state-specific techniques to minimize a mean square error criterion. In contrast to common memoryless estimation methods, additional information from adjacent signal frames can be exploited by utilizing the HMM. A consistent advantage of the new estimation rule is obtained compared to previously published HMM-based hard or soft classification methods.
Optical measurement of the converse piezoelectric d33 coefficients of bulk and microtubular zinc oxide crystals (2007)

Zinc oxide (ZnO) crystal is a semiconductor material; the direct measurement and the interpretation of its piezoelectric coefficients are challenging. In this letter, the authors investigate the piezoelectric properties (d33 coefficient) of a bulk ZnO sample by measuring its converse piezoelectric effect using an optical method. The experimental data agree with recent theoretical calculations. The piezoelectric properties of a ZnO hexagonal microtube, which has a highly symmetrical hexagonal tubular structure, are also studied. The results demonstrate that the microtubular ZnO has significantly different piezoelectric properties from that of ZnO bulk crystal, especially under the applied electric fields of low frequencies.
Relative enhancement of near-UV emission from a pulsed low-pressure mercury discharge lamp, using a rare gas mixture (2004)

In this paper, we explain the physical reasons for the enhancement of near-UV and visible emissions from a low-pressure mercury–argon discharge under pulse drive conditions. The conditions of operation that maximize the enhancement of near-UV and visible radiation, including the effect of the buffer gas, are investigated. We show that for a pulsed discharge, electron–ion recombination followed by cascade radiative transitions is the process responsible for most of the 365 nm emission and that argon with a small admixture of krypton is the buffer gas composition that leads to maximum radiative emission due to near-resonant energy transfers to mercury high-lying levels.
Scene modeling for wide area surveillance and image synthesis (2002)

We present a method for modeling a scene that is observed by a moving camera, where only a portion of the scene is visible at any time. This method uses mixture models to represent pixels in a panoramic view, and to construct a "background image" that contains only static (non-moving) parts of the scene. The method can be used to reliably detect moving objects in a video sequence, detect patterns of activity over a wide field of view, and remove moving objects from a video or panoramic mosaic. The method also yields improved results in detecting moving objects and in constructing mosaics in the presence of moving objects, when compared with techniques that are not based on scene modeling. We present examples illustrating the results.
Pathological features and inhaled corticosteroid response of eosinophilic and non-eosinophilic asthma (2007)

Non-eosinophilic asthma represents a pathologically distinct disease phenotype which is characterised by the absence of airway eosinophilia, normal subepithelial layer thickness and a poor short-term response to treatment with inhaled corticosteroids.
Quantum computers and dissipation (1996)

We analyse dissipation in quantum computation and its destructive impact on efficiency of quantum algorithms. Using a general model of decoherence, we study the time evolution of a quantum register of arbitrary length coupled with an environment of arbitrary coherence length. We discuss relations between decoherence and computational complexity and show that the quantum factorization algorithm must be modified in order to be regarded as efficient and realistic.
Angiopoietin-2, a Natural Antagonist for Tie2 That Disrupts in vivo Angiogenesis (1997)

Angiogenesis is thought to depend on a precise balance of positive and negative regulation. Angiopoietin-1 (Ang1) is an angiogenic factor that signals through the endothelial cell-specific Tie2 receptor tyrosine kinase. Like vascular endothelial growth factor, Ang1 is essential for normal vascular development in the mouse. An Ang1 relative, termed angiopoietin-2 (Ang2), was identified by homology screening and shown to be a naturally occurring antagonist for Ang1 and Tie2. Transgenic overexpression of Ang2 disrupts blood vessel formation in the mouse embryo. In adult mice and humans, Ang2 is expressed only at sites of vascular remodeling. Natural antagonists for vertebrate receptor tyrosine kinases are atypical; thus, the discovery of a negative regulator acting on Tie2 emphasizes the need for exquisite regulation of this angiogenic receptor system.
Guanosine nucleotide binding by highly purified Ha-ras-encoded p21 protein produced in Escherichia coli. (1984)

High-level expression of the p21 protein product of the BALB murine sarcoma virus v-ras gene (similar to the product of the Harvey murine sarcoma virus v-Ha-ras gene) has been reported recently, and highly purified preparations of this protein have been obtained. We used a nitrocellulose filter assay for measuring the binding of GDP and GTP to the purified protein. Previously p21 antibodies had been used to precipitate p21-guanosine nucleotide complexes from crude extracts containing the protein. Using the filter assay, we find that the v-Ha-ras gene product binds [3H]GDP stoichiometrically. The binding is time-dependent and is faster at 30 degrees C than at 0 degrees C. Optimum binding is obtained in the presence of dithiothreitol and magnesium ions and at pH 7.4. In terms of its GDP binding activity, p21 is heat stable and pronase sensitive. The dissociation constants (Kd) of p21 for [3H]GDP and [3H]GTP, determined by Scatchard analysis, are 6 X 10(-8) M and 2.5 X 10(-8) M, respectively.
Resorcinolic Lipids, the Natural Non-isoprenoid Phenolic Amphiphiles and Their Biological Activity (1998)

ADVERTISEMENT RETURN TO ISSUEArticleNEXTResorcinolic Lipids, the Natural Non-isoprenoid Phenolic Amphiphiles and Their Biological ActivityArkadiusz Kozubek and John H. P. TymanView Author Information Institute of Biochemistry and Molecular Biology, Department of Lipids and Liposomes, University of Wroclaw, Przybyszewskiego 63/77, 51-148 Wroclaw, Poland Institute of Physics and Environmental Sciences, Brunel University, Uxbridge, Middlesex UB8 3PH, United Kingdom Cite this: Chem. Rev. 1999, 99, 1, 1–26Publication Date (Web):December 24, 1998Publication History Received1 July 1997Revised6 November 1998Published online24 December 1998Published inissue 13 January 1999https://doi.org/10.1021/cr970464oCopyright © 1999 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views2215Altmetric-Citations421LEARN 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 Read OnlinePDF (485 KB) Get e-AlertscloseSUBJECTS:Aromatic compounds,Hydrocarbons,Lipids,Membranes,Reaction products Get e-Alerts