gebhart/patrepeval huggingface dataset:
Synthesis of Nanoscale Metal Oxide Particles Using Laser Vaporization/Condensation in a Diffusion Cloud Chamber (1994)

ADVERTISEMENT RETURN TO ISSUEArticleNEXTSynthesis of Nanoscale Metal Oxide Particles Using Laser Vaporization/Condensation in a Diffusion Cloud ChamberM. Samy El-Shall, W. Slack, W. Vann, D. Kane, and D. HanleyCite this: J. Phys. Chem. 1994, 98, 12, 3067–3070Publication Date (Print):March 1, 1994Publication History Published online1 May 2002Published inissue 1 March 1994https://pubs.acs.org/doi/10.1021/j100063a001https://doi.org/10.1021/j100063a001research-articleACS PublicationsRequest reuse permissionsArticle Views486Altmetric-Citations101LEARN 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 options Get e-Alerts
Media Distribution in Heterogeneous Environments using IP-Multicast (1998)

This document discusses problems and solutions around distribution of media in heterogeneous environments when using IP-multicast. Keywords: IP-multicast, real-time media, heterogeneous environments 1 Introduction When distributing real-time media with variable bit-rate using IP-multicast to a number of receivers over heterogeneous networks a problem of which bandwidth to transmit with occurs. More precisely, which bandwidth should be used when sending the media stream. If high bandwidth is chosen only the receivers with high bandwidth available the whole way to the sender will be able to receive the stream and those with little bandwidth will not be able to receive the stream. On the other hand, the least common bandwidth for the whole group could be chosen. This would allow for every member of the session to receive the stream but then the high bandwidth users would suffer from degraded media quality. This paper presents an overview of a number of proposals to solve this problem of...
Risk Alleles of USF1 -Gene Predict Cardiovascular Disease of Women in Two Prospective Studies (2005)

Upstream transcription factor 1 (USF1) is a ubiquitously expressed transcription factor controlling several critical genes in lipid and glucose metabolism.Of some 40 genes regulated by USF1, several are involved in the molecular pathogenesis of cardiovascular disease (CVD).Although the USF1 gene has been shown to have a critical role in the etiology of familial combined hyperlipidemia, which predisposes to early CVD, the gene's potential role as a risk factor for CVD events at the population level has not been established.Here we report the results from a prospective geneticepidemiological study of the association between the USF1 variants, CVD, and mortality in two large Finnish cohorts.Haplotype-tagging single nucleotide polymorphisms exposing all common allelic variants of USF1 were genotyped in a prospective case-cohort design with two distinct cohorts followed up during 1992-2001 and 1997-2003.The total number of follow-up years was 112,435 in 14,140 individuals, of which 2,225 were selected for genotyping based on the case-cohort study strategy.After adjustment for conventional risk factors, we observed an association of USF1 with CVD and mortality among females.In combined analysis of the two cohorts, female carriers of a USF1 risk haplotype had a 2-fold risk of a CVD event (hazard ratio [HR] 2.02; 95% confidence interval [CI] 1.16-3.53;p ¼ 0.01) and an increased risk of all-cause mortality (HR 2.52; 95% CI 1.46-4.35;p ¼ 0.0009).A putative protective haplotype of USF1 was also identified.Our study shows how a gene identified in exceptional families proves to be important also at the population level, implying that allelic variants of USF1 significantly influence the prospective risk of CVD and even allcause mortality in females.
Dry Etching of Single‐Crystal Silicon Trench in Hydrogen Iodide Containing Plasmas: I . Pure (1993)

Hydrogen iodide has been introduced for plasma etching of single‐crystal silicon trench. For part I of this work, pure chemistry has been investigated. forms an intensive, easily ignitable, and sustainable plasma, characterized by a very low self‐bias voltage, typically less than −80 V. The etching of silicon is only successful in the pressure range below 12 Pa. A suitable RF power range is from 150 to 300 W with an flow from 10 to 70 sccm. In these parameter ranges etch rates up to 400 nm/min can be obtained. The selectivity to the mask varies in the range from 30 to more than 150:1. The etch profile is tapered with a slope of 60 to 89°. In practical use we did not encounter any problems with the handling of or with contamination of the chamber and the pumps.
Trans-apical beating-heart implantation of neo-chordae to mitral valve leaflets: results of an acute animal study (2011)

The NeoChord DS1000 device for trans-apical beating-heart implantation of neo-chordae to the MV valve showed a high procedural success. A significant difference between an expert and beginner surgeon was detected, which emphasizes the importance of training before introduction of this new technique into clinical practice. Surgical workflow analysis proved to be a valuable tool to assess the performance of this new technique.
Spectrum Environment Machine Learning in Cognitive Radio (2012)

Using the theory of machine learning to spectrum cognition and management is a necessary requirement of realizing cognitive radio technology. In order to evaluate the performance of wireless channel spectrum sensing strategy effectively, the statistical mean value is put forward as evaluation criteria for the cognitive user with fixed rate service. Study shows that, for the objective license channel vacancy and occupancy state time with exponentially distribution as well as the same distribution parameter, vacancy state probability follows uniform distribution. Then, the paper analyses how the channel time detection threshold have an influence on throughput. With the increasing of sample size, the estimate of throughput converges in probability to its statistical mean value. Simulation indicates that the spectrum sensing throughput performance of the cognitive user with fixed rate service based on machine learning achieves better performance compared with random spectrum sensing. Ultimately, the channel time detection threshold is achieved when maximizing the statistical mean throughput.
Verarbeitung und Optimierung der Rezeptur von Wood Plastic Composites (WPC) (2007)

Wood Plastic Composites (WPC) bilden eine inzwischen beträchtlich wachsende Produktgruppe der Naturfaserverbundwerkstoffe. Diese kombinieren vorteilhafte anwendungstechnische Eigenschaften mit vergleichsweise kostengünstiger Verfügbarkeit. Derzeit sucht die europäische WPC-Industrie intensiv nach neuen Anwendungsbereichen, die für diese Werkstoffgruppe geeignet sind. Anwendungen von Spritzgießteilen aus WPC, z.B. in der Automobil- oder Möbelindustrie, könnten die jährliche Produktion enorm erhöhen. Hierfür müssten jedoch auch die Eigenschaften die hohen Erwartungskriterien erfüllen.Eine Vielzahl vorgängiger Arbeiten zeigt starke Abhängigkeit der Eigenschaften der WPC von der Art und der Morphologie der Holzfaser, der Kunststoffmatrix, dem Zuschlag von Additiven und der Folge daraus von den Verarbeitungsparameter. Das Ziel der vorliegenden Arbeit liegt in der Suche nach Zusammenhängen zwischen der systematischen Rezepturvariation, den Eigenschaften des Verbundes und der Verarbeitungsgüte beim Compoundieren und Spritzgießen von WPC. Die Fließeigenschaften werden in Abhängigkeit definierter Rezepturparameter quantitativ erfasst. Systematische Rezepturvariationen zur Wasseraufnahme und zum Einfluss von Additiv-Wachsen werden ebenfalls im Rahmen dieser Arbeit analysiert. Nicht zuletzt werde untersucht, wie verschiedene Verarbeitungstechnologien (Direktextrusion, Extrusion aus fertigen Compounds und Spritzgießen) die Eigenschaften von WPC mit vergleichbarer Zusammensetzung beeinflussen.
Efficient conversion of primary azides to aldehydes catalyzed by active site variants of myoglobin (2015)

The oxidation of primary azides to aldehydes constitutes a convenient but underdeveloped transformation for which no efficient methods are available. Here, we demonstrate that engineered variants of the hemoprotein myoglobin can catalyze this transformation with high efficiency (up to 8,500 turnovers) and selectivity across a range of structurally diverse aryl-substituted primary azides. Mutagenesis of the 'distal' histidine residue was particularly effective in enhancing the azide oxidation reactivity of myoglobin, enabling these reactions to proceed in good to excellent yields (37-89%) and to be carried out at a synthetically useful scale. Kinetic isotope effect, isotope labeling, and substrate binding experiments support a mechanism involving heme-catalyzed decomposition of the organic azide followed by alpha hydrogen deprotonation to generate an aldimine which, upon hydrolysis, releases the aldehyde product. This work provides the first example of a biocatalytic azide-to-aldehyde conversion and expands the range of non-native chemical transformations accessible through hemoprotein-mediated catalysis.
Molecular Mechanisms of General Genetic Recombination: The DNA-binding Sites of RecA Protein (1984)

The RecA protein of Escherichia coli mediates homologous pairing and strand exchange reactions similar to those of general genetic recombination. In vitro, this protein acts on suitable DNA molecules from phages or plasmids, converting them to heteroduplex recombination intermediates. We describe studies on RecA-mediated, reciprocal strand exchanges between two duplexes. Homologous pairing can occur if one duplex is partially single stranded (gapped) and leads to a strand exchange capable of passing and contributing to the repair of a two-strand break in the fully duplex molecule. However, it fails to pass a break in the gapped duplex. In related studies, we show that homologous pairing leading to strand exchange can occur between DNA molecules at positions where both are duplex.
An Unsupervised Approach for Automatic Activity Recognition Based on Hidden Markov Model Regression (2013)

Using supervised machine learning approaches to recognize human activities from on-body wearable accelerometers generally requires a large amount of labeled data. When ground truth information is not available, too expensive, time consuming or difficult to collect, one has to rely on unsupervised approaches. This paper presents a new unsupervised approach for human activity recognition from raw acceleration data measured using inertial wearable sensors. The proposed method is based upon joint segmentation of multidimensional time series using a Hidden Markov Model (HMM) in a multiple regression context. The model is learned in an unsupervised framework using the Expectation-Maximization (EM) algorithm where no activity labels are needed. The proposed method takes into account the sequential appearance of the data. It is therefore adapted for the temporal acceleration data to accurately detect the activities. It allows both segmentation and classification of the human activities. Experimental results are provided to demonstrate the efficiency of the proposed approach with respect to standard supervised and unsupervised classification approaches.
Functional architecture of Weibel-Palade bodies (2011)

Weibel-Palade bodies (WPBs) are elongated secretory organelles specific to endothelial cells that contain von Willebrand factor (VWF) and a variety of other proteins that contribute to inflammation, angiogenesis, and tissue repair. The remarkable architecture of WPBs is because of the unique properties of their major constituent VWF. VWF is stored inside WPBs as tubules, but on its release, forms strikingly long strings that arrest bleeding by recruiting blood platelets to sites of vascular injury. In recent years considerable progress has been made regarding the molecular events that underlie the packaging of VWF multimers into tubules and the processes leading to the formation of elongated WPBs. Mechanisms directing the conversion of tightly packaged VWF tubules into VWF strings on the surface of endothelial cells are starting to be unraveled. Several modes of exocytosis have now been described for WPBs, emphasizing the plasticity of these organelles. WPB exocytosis plays a role in the pathophysiology and treatment of von Willebrand disease and may have impact on common hematologic and cardiovascular disorders. This review summarizes the major advances made on the biogenesis and exocytosis of WPBs and places these recent discoveries in the context of von Willebrand disease.
CUDA memory limitation in finite element optimization to reconstruct cracks (2014)

In the nondestructive evaluation (NDE) of steel plates, besides the detection of cracks, what is also important is their characterization. Characterization is necessary for determining whether any discovered crack demands withdrawal of the part from service. In eddy current crack identification the response of a part to a coil is compared to the response without a crack. When different, the presence of the crack is flagged. But to characterize it, the computed response from eddy current analysis with a crack described by parameters is optimized to match measurements. This is heavy computation. Recently, Graphical Processing Unit (GPU) computing has had great success in many very large numerical computations. In this work we discuss the often undiscussed GPU memory limitation in Finite Element Optimization. In GPU computing the memory of the NVIDIA GPU is limited (4 GB on a PC today). This paper assesses the memory limits in terms of matrix size in light of the various ways to store a large matrix in order to overcome these limits. We revive old element-byelement finite element solvers from the early 1980s of working on a highly memory limited PC 282 to launch a GA kernel on thousands of CUDA threads exploiting the NVIDIA GPU architecture.
Morphogenesis of the First Blood Vessels (1998)

The initial phase of vessel formation is the establishment of nascent endothelial tubes from mesodermal precursor cells. Development of the vascular epithelium is examined using the transcription factor TAL1 as a marker of endothelial precursor cells (angioblasts), and a functional assay based on intact, whole-mounted quail embryos. Experimental studies examining the role(s) of integrins and vascular endothelial growth factor (VEGF) establish that integrin-mediated cell adhesion is necessary for normal endothelial tube formation and that stimulation of embryonic endothelial cells with exogenous VEGF results in a massive "fusion" of vessels and the obliteration of normally avascular zones. The second phase of vessel morphogenesis is assembly of the vessel wall. To understand the process by which mesenchyme gives rise to vascular smooth muscle, a novel monoclonal antibody, 1E12, that recognizes smooth muscle precursor cells was used. Additionally, development of the vessel wall was examined using the expression fo extracellular matrix proteins as markers. Comparison of labeling patterns of 1E12 and the extracellular matrix molecules fibulin-1 and fibrillin-2 indicate vessel wall heterogeneity at the earliest stages of development; thus smooth muscle cell diversity is manifested during the differentiation and assembly of the vessel wall. From these studies it is postulated that the extracellular matrix composition of the vessel wall may prove to be the best marker of smooth muscle diversity. The data are discussed in the context of recent work by others, especially provocative new studies suggesting an endothelial origin for vascular smooth muscle cells. Also discussed is recent work that provides clues to the mechanism of vascular smooth muscle induction and recruitment. Based on these findings, vascular smooth muscle cells can be thought of as existing along a continuum of phenotypes. This spectrum varies from mainly matrix-producing cells to primarily contractile cells; thus no one cell type typifies vascular smooth muscle. This view of the smooth muscle cell is considered in terms of a contrasting opinion that views smooth muscle cell as existing in either a synthetic or proliferative state.
Reconfigurable ferromagnetic liquid droplets (2019)

Solid ferromagnetic materials are rigid in shape and cannot be reconfigured. Ferrofluids, although reconfigurable, are paramagnetic at room temperature and lose their magnetization when the applied magnetic field is removed. Here, we show a reversible paramagnetic-to-ferromagnetic transformation of ferrofluid droplets by the jamming of a monolayer of magnetic nanoparticles assembled at the water-oil interface. These ferromagnetic liquid droplets exhibit a finite coercivity and remanent magnetization. They can be easily reconfigured into different shapes while preserving the magnetic properties of solid ferromagnets with classic north-south dipole interactions. Their translational and rotational motions can be actuated remotely and precisely by an external magnetic field, inspiring studies on active matter, energy-dissipative assemblies, and programmable liquid constructs.
Structural insights into protein-only RNase P complexed with tRNA (2013)

RNase P is the essential activity removing 5'-leader sequences from transfer RNA precursors. RNase P was always associated with ribonucleoprotein complexes before the discovery of protein-only RNase P enzymes called PRORPs (PROteinaceous RNase P) in eukaryotes. Here we provide biophysical and functional data to understand the mode of action of PRORP enzymes. Activity assays and footprinting experiments show that the anticodon domain of transfer RNA is dispensable, whereas individual residues in D and TψC loops are essential for PRORP function. PRORP proteins are characterized in solution and a molecular envelope is derived from small-angle X-ray scattering. Conserved residues are shown to be involved in the binding of one zinc atom to PRORP. These results facilitate the elaboration of a model of the PRORP/transfer RNA interaction. The comparison with the ribonucleoprotein RNase P/transfer RNA complex suggests that transfer RNA recognition by PRORP proteins is similar to that by ribonucleoprotein RNase P.
Multisite aggregation of p53 and implications for drug rescue (2017)

Protein aggregation is involved in many diseases. Often, a unique aggregation-prone sequence polymerizes to form regular fibrils. Many oncogenic mutants of the tumor suppressor p53 rapidly aggregate but form amorphous fibrils. A peptide surrounding Ile254 is proposed to be the aggregation-driving sequence in cells. We identified several different aggregating sites from limited proteolysis of harvested aggregates and effects of mutations on kinetics and products of aggregation. We present a model whereby the amorphous nature of the aggregates results from multisite branching of polymerization after slow unfolding of the protein, which may be a common feature of aggregation of large proteins. Greatly lowering the aggregation propensity of any one single site, including the site of Ile254, by mutation did not inhibit aggregation in vitro because aggregation could still occur via the other sites. Inhibition of an individual site is, accordingly, potentially unable to prevent aggregation in vivo. However, cancer cells are specifically killed by peptides designed to inhibit the Ile254 sequence and further aggregation-driving sequences that we have found. Consistent with our proposed mechanism of aggregation, we found that such peptides did not inhibit aggregation of mutant p53 in vitro. The cytotoxicity was not eliminated by knockdown of p53 in 2D cancer cell cultures. The peptides caused rapid cell death, much faster than usually expected for p53-mediated transcription-dependent apoptosis. There may also be non-p53 targets for those peptides in cancer cells, such as p63, or the peptides may alter other interactions of partly denatured p53 with receptors.
Preclinical Evaluation of AMG 925, a FLT3/CDK4 Dual Kinase Inhibitor for Treating Acute Myeloid Leukemia (2014)

Acute myeloid leukemia (AML) remains a serious unmet medical need. Despite high remission rates with chemotherapy standard-of-care treatment, the disease eventually relapses in a major proportion of patients. Activating Fms-like tyrosine kinase 3 (FLT3) mutations are found in approximately 30% of patients with AML. Targeting FLT3 receptor tyrosine kinase has shown encouraging results in treating FLT3-mutated AML. Responses, however, are not sustained and acquired resistance has been a clinical challenge. Treatment options to overcome resistance are currently the focus of research. We report here the preclinical evaluation of AMG 925, a potent, selective, and bioavailable FLT3/cyclin-dependent kinase 4 (CDK4) dual kinase inhibitor. AMG 925 inhibited AML xenograft tumor growth by 96% to 99% without significant body weight loss. The antitumor activity of AMG 925 correlated with the inhibition of STAT5 and RB phosphorylation, the pharmacodynamic markers for inhibition of FLT3 and CDK4, respectively. In addition, AMG 925 was also found to inhibit FLT3 mutants (e.g., D835Y) that are resistant to the current FLT3 inhibitors (e.g., AC220 and sorafenib). CDK4 is a cyclin D-dependent kinase that plays an essential central role in regulating cell proliferation in response to external growth signals. A critical role of the CDK4-RB pathway in cancer development has been well established. CDK4-specific inhibitors are being developed for treating RB-positive cancer. AMG 925, which combines inhibition of two kinases essential for proliferation and survival of FLT3-mutated AML cells, may improve and prolong clinical responses.
Wavelet‐encoded MR imaging (1992)

Wavelet encoding is presented and compared to phase encoding. In wavelet encoding a distribution of spins is excited by a slice selective RF pulse; for each repetition time the distribution excited has the profile of a wavelet at different scale and translation. The spin density can be reconstructed with an inverse wavelet transform. Wavelet encoding has three advantages over phase encoding: (1) there is no Gibb's ringing from partial volume effects, (2) the effective repetition time can be 36 times the repetition time for a 256 x 256 image, and (3) motion artifacts are local and dramatically reduced. Using wavelet encoding, a 256 x 256 T2-weighted projection image can be acquired in 33 s.
Extending the Upper Temperature Limit for Life (2003)

The upper temperature limit for life is a key parameter for delimiting when and where life might have evolved on a hot, early Earth; the depth to which life exists in the Earth's subsurface; and the potential for life in hot, extraterrestrial environments. A combination of geological and