gebhart/patrepeval huggingface dataset:
Studies on multilayer film coextrusion III. The rheology of blown film coextrusion (1978)

Abstract Multilayer blown film coextrusion was studied, both experimentally and theoretically. For the experimental study, an annular die with a feed‐port system was designed and multilayer blown films were produced by rotating the inner mandrel with a one horsepower variable‐speed drive at speeds from nearly 2 to 6 rpm, and by inflating the tubular molten film with air. The die has 16 feed slots and melt pressure transducers are mounted along the axial direction of the outer wall of the annular flow channel. The transducers were used to determine the pressure gradient in the annular flow channel, which then permitted determination of the reduction in pressure drop when different combinations of two polymer systems were coextruded. Polymers used for b own film coextrusion were: (1) low‐density polyethylene with ethylene‐vinyl acetate; (2) low‐density polyethylene with high‐density polyethylene; (3) low‐density polyethylene with polypropylene; (4) high‐density polyethylene with ethylene‐vinyl acetate. For the theoretical study, stratified helical flow was analyzed using a power‐law non‐Newtonian model. A computational procedure was developed to predict the number of layers, layer thickness, and the volumetric flow rate as functions of certain processing variables (namely, the pressure drop in the die, and the angular speed of rotation of the inner mandrel of the die) and the rheological parameters of the individual polymers concerned. Comparison was made of the theoretical prediction of volumetric flow rate with experimental ones. Some representative results are presented of the theoretically predicted axial and angular velocity distributions, shear stress profiles, and shear rate profiles.
Sources Near The Free-Surface Boundary: Pitfalls for Elastic Finite-Difference Seismic Simulation And Multi-Grid Waveform Inversion (2008)

Elastic full-waveform inversion requires the capability to efficiently do accurate forward seismic&lt;br&gt;simulations based upon an earth model. The rotated staggered grid (Saenger, 2000) has been&lt;br&gt;a great advance for accurate elastic wave simulation in isotropic and anisotropic media but has&lt;br&gt;requirements that complicate source insertion too close to a free surface boundary. Coarse-grid&lt;br&gt;simulations limited to lower-frequency components in the data are frequently used to accelerate&lt;br&gt;early stages of waveform inversion both for computational efficiency and to better condition the&lt;br&gt;inversion (Bunks et al., 1995). This works better for acoustic waveform inversion than in the&lt;br&gt;elastic case. In the elastic case, the free-surface boundary requires a fine spatial grid both for&lt;br&gt;accurate computation of surface waves and for accurate source insertion. These requirements&lt;br&gt;offset part of the multi-grid advantage, especially for typical seismic acquisition geometries with&lt;br&gt;sources and receivers located somewhere near the surface of the earth.
Catalytic IgG from Patients with Hemophilia A Inactivate Therapeutic Factor VIII (2006)

Factor VIII (FVIII) inhibitors are anti-FVIII IgG that arise in up to 50% of the patients with hemophilia A, upon therapeutic administration of exogenous FVIII. Factor VIII inhibitors neutralize the activity of the administered FVIII by sterically hindering its interaction with molecules of the coagulation cascade, or by forming immune complexes with FVIII and accelerating its clearance from the circulation. We have shown previously that a subset of anti-factor VIII IgG hydrolyzes FVIII. FVIII-hydrolyzing IgG are detected in over 50% of inhibitor-positive patients with severe hemophilia A, and are not found in inhibitor-negative patients. Although human proficient catalytic Abs have been described in a number of inflammatory and autoimmune disorders, their pathological relevance remains elusive. We demonstrate here that the kinetics of FVIII degradation by FVIII-hydrolyzing IgG are compatible with a pathogenic role for IgG catalysts. We also report that FVIII-hydrolyzing IgG from each patient exhibit multiple cleavage sites on FVIII and that, while the specificity of cleavage varies from one patient to another, catalytic IgG preferentially hydrolyze peptide bonds containing basic amino acids.
Mechanism of Inhibition of β-Site Amyloid Precursor Protein-cleaving Enzyme (BACE) by a Statine-based Peptide (2001)

Inhibition of beta-site amyloid precursor protein-cleaving enzyme by a statine-based inhibitor has been studied using steady state and stopped-flow methods. A slow onset rate of inhibition has been observed under steady state conditions, and a K(i) of 22 nm has been derived using progress curves analysis. Simulation of stopped-flow protein fluorescence transients provided an estimate of the K(d) for initial inhibitor binding of 660 nm. A two-step inhibition mechanism is proposed, wherein slower "tightening up" of the initial encounter complex occurs. Two hypotheses have been proposed in the literature to address the nature of the slow step in the inhibition of aspartic proteases by peptidomimetic inhibitors: a conformational change related to the "flap" movement and displacement of a catalytic water. We compared substrate and inhibitor binding rates under pre-steady-state conditions. Both ligands are likely to cause flap movement, whereas no catalytic water replacement occurs during substrate binding. Our results suggest that both ligands bind to the enzyme at a rate significantly lower than the diffusion limit, but there are additional rate limitations involved in inhibitor binding, resulting in a k(on) of 3.5 x 10(4) m(-)1 s(-)1 for the inhibitor compared with 3.5 x 10(5) m(-)1 s(-)1 for the substrate. Even though specific intermediate formation steps might be different in the productive inhibitor and substrate binding to beta-site amyloid precursor protein-cleaving enzyme, a similar final optimized conformation is achieved in both cases, as judged by the comparable free energy changes (DeltaDeltaG of 2.01 versus 1.97 kcal/mol) going from the initial to the final enzyme-inhibitor or enzyme-substrate complexes.
Metabolites with Nematicidal and Antimicrobial Activities from the Ascomycete Lachnum papyraceum(Karst.) Karst. V. Production, Isolation and Biological Activities of Bromine-containing Mycorrhizin and Lachnumon Derivatives and Four Additional New Bioactive Metabolites. (1995)

Eight novel bioactive metabolites were isolated from submerged cultures of the ascomycete Lachnum papyraceum (Karst.) Karst, when CaBr2 was added to the cultures after the onset of secondary metabolism. Four of these metabolites (16 to 19) are bromo analogues of mycorrhizin A and lachnumon, while (l'Z)-dechloromycorrhizin A (12) and the papyracons A (13), B (14), and C (15) are non-halogenated compounds structurally related to the mycorrhizins. All compounds exhibited antimicrobial, cytotoxic, nematicidal and phytotoxic activities. The brominated mycorrhizins and lachnumons were found to be slightly less active than the chlorine-containing compounds. All mycorrhizin derivatives were mutagenic in the Ames test, suggesting DNA-alkylating properties.
The PARP inhibitor Olaparib disrupts base excision repair of 5-aza-2′-deoxycytidine lesions (2014)

Decitabine (5-aza-2'-deoxycytidine, 5-azadC) is used in the treatment of Myelodysplatic syndrome (MDS) and Acute Myeloid Leukemia (AML). Its mechanism of action is thought to involve reactivation of genes implicated in differentiation and transformation, as well as induction of DNA damage by trapping DNA methyltranferases (DNMT) to DNA. We demonstrate for the first time that base excision repair (BER) recognizes 5-azadC-induced lesions in DNA and mediates repair. We find that BER (XRCC1) deficient cells are sensitive to 5-azadC and display an increased amount of DNA single- and double-strand breaks. The XRCC1 protein co-localizes with DNMT1 foci after 5-azadC treatment, suggesting a novel and specific role of XRCC1 in the repair of trapped DNMT1. 5-azadC-induced DNMT foci persist in XRCC1 defective cells, demonstrating a role for XRCC1 in repair of 5-azadC-induced DNA lesions. Poly (ADP-ribose) polymerase (PARP) inhibition prevents XRCC1 relocation to DNA damage sites, disrupts XRCC1-DNMT1 co-localization and thereby efficient BER. In a panel of AML cell lines, combining 5-azadC and Olaparib cause synthetic lethality. These data suggest that PARP inhibitors can be used in combination with 5-azadC to improve treatment of MDS and AML.
Wireless communications with unmanned aerial vehicles: opportunities and challenges (2016)

Wireless communication systems that include unmanned aerial vehicles promise to provide cost-effective wireless connectivity for devices without infrastructure coverage. Compared to terrestrial communications or those based on high-altitude platforms, on-demand wireless systems with low-altitude UAVs are in general faster to deploy, more flexibly reconfigured, and likely to have better communication channels due to the presence of short-range line-of-sight links. However, the utilization of highly mobile and energy-constrained UAVs for wireless communications also introduces many new challenges. In this article, we provide an overview of UAV-aided wireless communications, by introducing the basic networking architecture and main channel characteristics, highlighting the key design considerations as well as the new opportunities to be exploited.
Calichemicins, a novel family of antitumor antibiotics. 2. Chemistry and structure of calichemicin .gamma.1I (1987)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCalichemicins, a novel family of antitumor antibiotics. 2. Chemistry and structure of calichemicin .gamma.1IMay D. Lee, Theresa S. Dunne, Conway C. Chang, George A. Ellestad, Marshall M. Siegel, George O. Morton, William J. McGahren, and Donald B. BordersCite this: J. Am. Chem. Soc. 1987, 109, 11, 3466–3468Publication Date (Print):May 1, 1987Publication History Published online1 May 2002Published inissue 1 May 1987https://pubs.acs.org/doi/10.1021/ja00245a051https://doi.org/10.1021/ja00245a051research-articleACS PublicationsRequest reuse permissionsArticle Views742Altmetric-Citations350LEARN 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
Molecular Materials by Self‐Assembly of Porphyrins, Phthalocyanines, and Perylenes (2006)

Abstract Porphyrins, phthalocyanines, and perylenes are compounds with great potential for serving as components of molecular materials that possess unique electronic, magnetic and photophysical properties. In general, a highly specific communication between a large number of these chromophores is required in order to express their function to a maximal level, and for this reason it is of importance to construct arrays in which the molecules are organized in well‐defined geometries with respect to their neighbors. This review is an account of some recent efforts to construct highly ordered assemblies of porphyrins, phthalocyanines, and perylenes by means of self‐assembly in solution and on surfaces, and by attaching them to polymeric scaffolds.
Metabolic Engineering of Oleaginous Yeasts for Production of Fuels and Chemicals (2017)

Oleaginous yeasts have been increasingly explored for production of chemicals and fuels via metabolic engineering. Particularly, there is a growing interest in using oleaginous yeasts for the synthesis of lipid-related products due to their high lipogenesis capability, robustness, and ability to utilize a variety of substrates. Most of the metabolic engineering studies in oleaginous yeasts focused on <i>Yarrowia</i> that already has plenty of genetic engineering tools. However, recent advances in systems biology and synthetic biology have provided new strategies and tools to engineer those oleaginous yeasts that have naturally high lipid accumulation but lack genetic tools, such as <i>Rhodosporidium</i>, <i>Trichosporon</i>, and <i>Lipomyces</i>. This review highlights recent accomplishments in metabolic engineering of oleaginous yeasts and recent advances in the development of genetic engineering tools in oleaginous yeasts within the last 3 years.
A 3.3-V power adaptive 1244/622/155 Mbit/s transceiver for ATM, SONET/SDH (1998)

This paper presents the implementation of a multirate 155-, 622-, or 1244-Mbit/s transceiver for ATM and SDH/SONET in a 0.5-/spl mu/m BiCMOS. The internal high-speed clock generation is based on PLL's with 1.24-GHz VCO's. The solutions presented here allow us to get rid of the external trimming of the free-running frequency of VCO. The automatic adjustment of the clock and data recovery PLL VCO free running is performed, and thus, increases the robustness of the RX function without expenses in manual trimming. The architecture of this transceiver is thought to enable the full-frequency Wafer test of the whole core by specific loop-back modes. As the same core is used for 155-Mbit/s, 622-Mbit/s, and 1.2-Gbit/s power adaptation techniques are implemented which lead to a 660-mW consumption for 155-Mbit/s operation and 1.1 W for 1.24 Gbits/s. A specific digitally programmable power adaptive ECL cell library concept is presented. Noise precautions are also described, as well as an analog HDL top-down methodology developed by SGS-Thomson Central R&D to short-down the development time and increase reusability.
Dysregulation of microRNAs after myocardial infarction reveals a role of miR-29 in cardiac fibrosis (2008)

Acute myocardial infarction (MI) due to coronary artery occlusion is accompanied by a pathological remodeling response that includes hypertrophic cardiac growth and fibrosis, which impair cardiac contractility. Previously, we showed that cardiac hypertrophy and heart failure are accompanied by characteristic changes in the expression of a collection of specific microRNAs (miRNAs), which act as negative regulators of gene expression. Here, we show that MI in mice and humans also results in the dysregulation of specific miRNAs, which are similar to but distinct from those involved in hypertrophy and heart failure. Among the MI-regulated miRNAs are members of the miR-29 family, which are down-regulated in the region of the heart adjacent to the infarct. The miR-29 family targets a cadre of mRNAs that encode proteins involved in fibrosis, including multiple collagens, fibrillins, and elastin. Thus, down-regulation of miR-29 would be predicted to derepress the expression of these mRNAs and enhance the fibrotic response. Indeed, down-regulation of miR-29 with anti-miRs in vitro and in vivo induces the expression of collagens, whereas over-expression of miR-29 in fibroblasts reduces collagen expression. We conclude that miR-29 acts as a regulator of cardiac fibrosis and represents a potential therapeutic target for tissue fibrosis in general.
Acoustoelectrooptic multichannel spectrum analyzer (1986)

The acoustoelectrooptic effect is combined with the conventional acoustooptic spectrum analyzer. This eliminates the trade-off between the bandwidth and diffraction efficiency and the bandwidth limit of the ordinary acoustooptic spectrum analyzer. Three possible schemes for realizing this concept are proposed.
Interaction of platelet-derived growth factor with thrombospondin 1 (1997)

Key factors that mediate vascular smooth muscle cell proliferation and migration are platelet-derived growth factor (PDGF) and thrombospondin 1 (TSP1). We now report that PDGFBB bound tightly and specifically to TSP1, that this interaction was markedly dependent on the disulphide bond arrangement in TSP1, and that binding of PDGFBB to TSP1 did not preclude PDGFBB from binding to its receptor on rat aortic vascular smooth-muscle cells. At physiological ionic strength and pH, PDGFBB bound to Ca2+-depleted TSP1 with a dissociation constant of 11±2 nM and to Ca2+-replete TSP1 with a dissociation constant of 32±5 nM. Binding was specific, as both soluble TSP1 and unlabelled PDGFBB competed for binding of iodinated PDGFBB to immobilized TSP1, whereas other platelet α-granule proteins did not compete. The tertiary structure of TSP1 is regulated by intramolecular disulphide interchange; we found that catalysis of disulphide interchange in TSP1 by protein disulphide isomerase ablated the binding of PDGFBB. The interaction of PDGFBB with TSP1 was weakened by increasing salt concentration and essentially ablated at 0.65 ionic strength; it was inhibited by heparin with a half-maximal effect at 20 i.u./ml, implying that the binding was mediated largely by ionic interactions. An anti TSP1 monoclonal antibody decreased the binding of iodinated PDGFBB to PDGF receptor on rat aortic vascular smooth-muscle cells by 37±2%, whereas platelet TSP1 non-competitively inhibited binding of iodinated PDGFBB. Uncomplexed PDGFBB bound to PDGF receptor with an affinity 5±2 times that of PDGFBB–TSP1 complexes. These results suggest that TSP1 might assist in the targeting of PDGF to its receptor on vascular smooth-muscle cells.
Serum free amino acid content in hamsters with cheek pouch carcinoma. (1992)

9, 10-dimethyl-1, 2-benzanthracene塗布により左側頬嚢粘膜に発癌させたハムスターの血清遊離アミノ酸濃度を, PICO-TAGアミノ酸分析システムにて測定, 実験群18匹, 対照群8匹の平均値を比較した。総アミノ酸量には有意の差はみられなかったが, 11種のアミノ酸が減少傾向を示し, 特にトリプトファソとスレオニンは約1/2, バリソとオルニチンならびにグルタミン酸は有意に減少した。一方アスパラギン酸とシスタチオニソは2倍以上の増加を示し, アミノ酸代謝に変化が起きていることを示した。
Dynamic association of capping enzymes with transcribing RNA polymerase II (2000)

The C-terminal heptad repeat domain (CTD) of RNA polymerase II (pol II) is proposed to target pre-mRNA processing enzymes to nascent pol II transcripts, but this idea has not been directly tested in vivo. In vitro, the yeast mRNA capping enzymes Ceg1 and Abd1 bind specifically to the phosphorylated CTD. Here we show that yeast capping enzymes cross-link in vivo to the 5' ends of transcribed genes and that this localization requires the CTD. Both the extent of CTD phosphorylation at Ser 5 of the heptad repeat and the binding of capping enzymes decreased as polymerase moved from the 5' to the 3' ends of the ACT1, ENO2, TEF1, GAL1, and GAL10 genes. Ceg1 is released early in elongation, but Abd1 can travel with transcribing pol II as far as the 3' end of a gene. The CTD kinase, Kin28, is required for binding, and the CTD phosphatase, Fcp1, is required for dissociation of capping enzymes from the elongation complex. CTD phosphorylation and dephosphorylation therefore control the association of capping enzymes with pol II as it transcribes a gene.
Size-dependent internalization of particles via the pathways of clathrin- and caveolae-mediated endocytosis (2004)

Non-phagocytic eukaryotic cells can internalize particles <1 microm in size, encompassing pathogens, liposomes for drug delivery or lipoplexes applied in gene delivery. In the present study, we have investigated the effect of particle size on the pathway of entry and subsequent intracellular fate in non-phagocytic B16 cells, using a range of fluorescent latex beads of defined sizes (50-1000 nm). Our data reveal that particles as large as 500 nm were internalized by cells via an energy-dependent process. With an increase in size (50-500 nm), cholesterol depletion increased the efficiency of inhibition of uptake. The processing of the smaller particles was significantly perturbed upon microtubule disruption, while displaying a negligible effect on that of the 500 nm beads. Inhibitor and co-localization studies revealed that the mechanism by which the beads were internalized, and their subsequent intracellular routing, was strongly dependent on particle size. Internalization of microspheres with a diameter <200 nm involved clathrin-coated pits. With increasing size, a shift to a mechanism that relied on caveolae-mediated internalization became apparent, which became the predominant pathway of entry for particles of 500 nm in size. At these conditions, delivery to the lysosomes was no longer apparent. The data indicate that the size itself of (ligand-devoid) particles can determine the pathway of entry. The clathrin-mediated pathway of endocytosis shows an upper size limit for internalization of approx. 200 nm, and kinetic parameters may determine the almost exclusive internalization of such particles along this pathway rather than via caveolae.
The Glycosaminoglycan of Recombinant Human Soluble Thrombomodulin Affects Antithrombotic Activity in a Rat Model of Tissue Factor-Induced Disseminated Intravascular Coagulation (1992)

Previous studies on recombinant human soluble thrombomodulin (rsTM) from Chinese hamster ovary cells revealed that rsTM was expressed as two proteins that differed functionally in vitro due to the presence (rsTM beta) or absence (rsTM alpha) of chondroitin-4-sulfate. The current study evaluates the in vivo behavior of rsTM in rats and in a rat model of tissue factor-induced disseminated intravascular coagulation (DIC). rsTM beta was more potent than rsTM alpha for prolongation of the activated partial thromboplastin time (APTT) and their in vivo half-lives determined by ELISA were 20 min for rsTM beta and 5.0 h for rsTM alpha. Injection of a tissue factor suspension (5 mg/kg) resulted in DIC as judged by decreased platelet counts and fibrinogen concentrations, prolonged APTT, and increased fibrin and fibrinogen degradation products (FDP) levels. A bolus injection of either rsTM (0.2 mg/kg) 1 min before induction of DIC essentially neutralized effects on platelets, fibrinogen, and FDP levels, and had only a moderate effect on APTT prolongation. The dose of anticoagulant to inhibit the drop in platelet counts by 50% (ED50) was 0.2 mg/kg rsTM alpha, 0.07 mg/kg rsTM beta, and 7 U/kg heparin. The effect of increasing concentrations of rsTM and heparin on bleeding times were compared in experiments involving incision of the rat tail. Doubling of the bleeding times occurred at 5 mg/kg rsTM alpha, 3 mg/kg rsTM beta or 90 U/kg heparin. These values represent a 25-fold increase over the ED50 for rsTM alpha, 43-fold for rsTM beta and 13-fold for heparin.(ABSTRACT TRUNCATED AT 250 WORDS)
A mixture linear model with target-directed dynamics for spontaneous speech recognition (2002)

In this paper, a mixture linear dynamic model (MLDM) for speech recognition is developed and evaluated, where several linear dynamic systems are combined (mixed) to represent different vocaltract-resonance (VTR) dynamic behavior and the mapping relationships between the VTRs and the acoustic observation. Each linear dynamic model is formulated as a stale-space system, where the VTR's target-directed dynamic property is incorporated in the state equation and a linear regression function is used for the observation equation to piecewise linearly approximate the nonlinear mapping relationship. A version of the generalized EM algorithm is developed for learning the model parameters, where the VTR targets are constrained to change only at the segmental level (rather than at the frame level) in the parameter learning and model scoring algorithms. Speech recognition experiments are carried out to evaluate this new model using the N-best re-scoring paradigm in a Switchboard task. Compared with a baseline recognizer using the triphone HMM acoustic model, the new recognizer demonstrates superior performance under a number of experimental conditions.