gebhart/patrepeval huggingface dataset:
Dehydrogenative coupling of diarylsilanes (1989)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDehydrogenative coupling of diarylsilanesLihsueh S. Chang and Joyce Y. CoreyCite this: Organometallics 1989, 8, 8, 1885–1893Publication Date (Print):August 1, 1989Publication History Published online1 May 2002Published inissue 1 August 1989https://pubs.acs.org/doi/10.1021/om00110a010https://doi.org/10.1021/om00110a010research-articleACS PublicationsRequest reuse permissionsArticle Views1291Altmetric-Citations94LEARN 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-Alertsclose Get e-Alerts
Solution-Phase Extraction of Ultrathin Inner Shells from Double-Wall Carbon Nanotubes (2010)

We present an efficient method to extract inner shells of double-wall carbon nanotubes (DWCNTs) in liquid phase. The extraction of inner from outer shells is achieved by cutting the DWCNTs with vigorous sonication in water containing surfactants. The extracted shells are perfectly isolated single-wall carbon nanotubes (SWCNTs) and can be separated using density gradient ultracentrifugation. Statistical analysis using high-resolution transmission electron microscopy reveals that the enrichment of SWCNTs with narrow diameter (0.62-1.0 nm) up to 100% is achieved from highly pure DWCNTs. Furthermore, the (5,4) SWCNTs, which have the diameter of 0.62 nm, are concentrated. Our findings provide a novel way to obtain very narrow, highly isolated SWCNTs with ultraclean surface that have not been obtained in conventional synthesis methods.
Pyrroloquinoline Quinone Biogenesis:  Characterization of PqqC and Its H84N and H84A Active Site Variants (2007)

Pyrroloquinoline quinone [4,5-dihydro-4,5-dioxo-1H-pyrrolo[2,3-f]quinoline-2,7,9-tricarboxylic acid (PQQ)] is a bacterial vitamin that serves as a cofactor in numerous alcohol dehydrogenases. Its biosynthesis in Klebsiella pneumoniae is facilitated by six genes, pqqABCDEF, and proceeds by an unknown pathway. The protein encoded by pqqC catalyzes the final step of PQQ formation, which involves a ring closure and an overall eight-electron oxidation of 3a-(2-amino-2-carboxyethyl)-4,5-dioxo-4,5,6,7,8,9-hexahydroquinoline-7,9-dicarboxylic acid (AHQQ) in the absence of a redox-active metal or cofactor. A recent crystal structure has implicated numerous PQQ-PqqC interactions [Magnusson et al. (2004) Proc. Natl. Acad. Sci. U.S.A. 101, 7913-7918]. To investigate the mechanism of the PqqC reaction, the active site residue His84 has been mutated to H84A and H84N, and the kinetic and spectroscopic properties have been compared to each other and the wild-type enzyme using aerobic and anaerobic conditions. Both mutants form PQQ under aerobic conditions with rate constants of 0.09 min-1 and 0.056 min-1 relative to 0.34 min-1 for the wild-type enzyme. In addition to the initial E-AHQQ complex (532-536 nm) and the product E-PQQ complex (346-366 nm), a number of spectral intermediates are observed between 316 and 344 nm. The anaerobic reaction is particularly informative, showing that while mixing of H84N with AHQQ leads to a 344 nm intermediate, this is unable to proceed to a final 318 nm species; by contrast H84A forms the 344 nm species as a precursor to the 318 nm species. In the context of the proposed chemical mechanism for PqqC [Magnusson et al. (2004) Proc. Natl. Acad. Sci. U.S.A. 101, 7913-7918], we assign the 344 nm intermediate to a quinoid species and the 318 nm intermediate to an initial quinol species. The proposed role of H84 is as a proton donor to the oxyanion of the quinoid species such that subsequent C-H bond cleavage can occur to form a monoanionic quinol. In the absence of a proton donor (as occurs in H84N), the normal reaction path is precluded as this would require formation of an unstable, dianionic species. Unlike H84N, H84A appears to be small enough to allow entry of active site water, which is postulated to adopt the role of active site proton donor.
Muscle and Liver Insulin Resistance Indexes Derived From the Oral Glucose Tolerance Test (2006)

Novel estimates for hepatic and muscle insulin resistance from OGTT data are presented for quantitation of insulin sensitivity in nondiabetic subjects.
<title>Perceptual quality measure using a spatiotemporal model of the human visual system</title> (1996)

This paper addresses the problem of quality estimation of digitally coded video sequences. The topic is of great interest since many products in digital video are about to be released and it is thus important to have robust methodologies for testing and performance evaluation of such devices. The inherent problem is that human vision has to be taken into account in order to assess the quality of a sequence with a good correlation with human judgment. It is well known that the commonly used metric, the signal-to-noise ratio is not correlated with human vision. A metric for the assessment of video coding quality is presented. It is based on a multi-channel model of human spatio-temporal vision that has been parameterized for video coding applications by psychophysical experiments. The visual mechanisms of vision are simulated by a spatio-temporal lter bank. The decomposition is then used to account for phenomena as contrast sensitivity and masking. Once the amount of distortions actually perceived is known, quality estimation can be assessed at various levels. The described metric is able to rate the overall quality of the decoded video sequence as well as the rendition of important features of the sequence such as contours or textures.
Low-resistance self-aligned Ti-silicide technology for sub-quarter micron CMOS devices (1996)

A low-resistance self-aligned Ti-silicide process featuring selective silicon deposition and subsequent pre-amorphization (SEDAM) is proposed and characterized for sub-quarter micron CMOS devices. 0.15-/spl mu/m CMOS devices with low-resistance and uniform TiSi/sub 2/ on gate and source/drain regions were fabricated using the SEDAM process. Non-doped silicon films were selectively deposited on gate and source/drain regions to reduce suppression of silicidation due to heavily-doped As in the silicon. Silicidation was also enhanced by pre-amorphization, using ion-implantation, on the narrow gate and source/drain regions. Low-resistance and uniform TiSi/sub 2/ films were achieved on all narrow, long n/sup +/ and p/sup +/ poly-Si and diffusion layers of 0.15-/spl mu/m CMOS devices. TiSi/sub 2/ films with a sheet resistance of 5 to 7 /spl Omega//sq were stably and uniformly formed on 0.15-/spl mu/m-wide n/sup +/ and p/sup +/ poly-Si. No degradation in leakage characteristics was observed in pn-junctions with TiSi/sub 2/ films. It was confirmed that, using SEDAM, excellent device characteristics were achieved for 0.15-/spl mu/m NMOSFET's and PMOSFET's with self-aligned TiSi/sub 2/ films.
Continuous Monitoring of Cerebral Substrate Delivery and Clearance: Initial Experience in 24 Patients with Severe Acute Brain Injuries (1997)

Brain oxygen pressure, brain carbon dioxide pressure, and brain pH measurements, as well as a microdialysis probe for glucose and lactate analysis, may optimize the management of comatose neurosurgical patients by allowing a fuller understanding of the dynamic factors affecting brain metabolism.
Implementation of a real-time DMT-based 100 Mbit/s visible-light link (2010)

For the first time, we show an implementation of a real-time DMT-based system operating at 100 Mbit/s over a visible-light link using a low-cost commercially available white LED devised for illumination. Additionally, we demonstrate transmission of a video signal over this link.
Molecular cloning of a histidine-rich Ca2+-binding protein of sarcoplasmic reticulum that contains highly conserved repeated elements (1989)

We reported previously the purification of a 165-kDa muscle-specific protein identified by virtue of its ability to bind 125I-labeled low density lipoprotein with high affinity after sodium dodecyl sulfate-polyacrylamide gel electrophoresis (Hoffmann, S. L., Brown, M. S., Lee, E., Pathak, R. K., Anderson, R. G. W., and Goldstein, J. J. (1989) J. Biol. Chem. 264, 8260-8270). The protein is located in the lumen of the sarcoplasmic reticulum, where it has no access to plasma lipoproteins. It binds to 45Ca2+ on nitrocellulose blots and stains metachromatically blue with Stains-all, a cationic dye that stains Ca2+-binding proteins. In the current paper, we have isolated a full-length rabbit cDNA clone for the 165-kDa protein. The deduced amino acid sequence reveals a 852-amino acid protein with the following structural features: 1) an NH2-terminal 27-residue putative signal sequence; 2) a highly repetitive region containing nine nearly identical tandem repeats of 29 residues, each consisting of a histidine-rich sequence HRHRGH, a stretch of 10-11 acidic amino acids, and a sequence containing 2 serines and a threonine in a negatively charged context; 3) a 13-residue stretch of polyglutamic acid; and 4) a COOH-terminal cluster of 14 closely spaced cysteine residues with the repeating pattern of Cys-X-X-Cys suggestive of a heavy metal binding domain. Histidine, aspartic acid, and glutamic acid accounted, respectively, for 13, 12, and 19% of the amino acids. The protein does not share any significant sequence homology with the cell surface low density lipoprotein receptor. Stretches of acidic amino acids are a feature of two other luminal sarcoplasmic reticulum proteins, suggesting that these may be a general feature of luminal sarcoplasmic reticulum proteins. We suggest that the histidine-rich Ca2+-binding protein described in the current study be designated HCP. The role of HCP in Ca2+ homeostasis in the sarcoplasmic reticulum of skeletal and cardiac muscle remains to be determined.
Wideband Mixed-Domain Multi-Tap Finite-Impulse Response Filtering of Out-of-Band Noise Floor in Watt-Class Digital Transmitters (2017)

A major drawback of digital transmitters (DTX) is the absence of a reconstruction filter after digital-to-analog conversion which causes the baseband quantization noise to get upconverted to radio frequency and amplified at the output of the transmitter. In high power transmitters, this upconverted noise can be so strong as to prevent their use in frequency-division duplexing systems due to receiver desensitization or impose stringent coexistence challenges. In this paper, we describe a DTX that embeds mixed-domain multi-tap finite-impulse response (FIR) filtering with programmable analog sub-sample delays within a highly linear and mismatch-resilient switched-capacitor DTX architecture. It is shown that switched-capacitor power amplifiers (SCPA) in conjunction with transformer-based power combining are ideal candidates for embedding mixed-domain FIR filtering since the near-constant source impedance of the SCPA greatly aids in linear FIR summation thereby preserving the desired noise-shaping profile. Moreover, their excellent mismatch characteristics help in ensuring precise tap weights in the FIR which enhances noise suppression. The availability of multiple taps in this architecture also allows the synthesis of FIR configurations with wide notch bandwidths (BW). Theoretical analyses of this architecture and design trade-offs related to linearity, mismatch, output power, and efficiency are discussed. The implemented 65 nm CMOS prototype exhibits a peak output power of 30.3 dBm and a peak system efficiency of 34%, and achieves a noise floor of -149 dBc/Hz over a BW of 20 MHz at an offset of 135 MHz from a 2.23 GHz carrier while transmitting a 1.4 MHz 64-QAM signal with an average output power of 22 dBm.
Inertia Estimation of the GB Power System Using Synchrophasor Measurements (2014)

A novel procedure for estimating the total inertia of the Great Britain (GB) power system is presented. Following an instantaneous in-feed loss, regional variations in the estimate of inertia are obtained from measured frequency transients using installed synchronised phasor measurement units (PMUs). A method is proposed to first detect a suitable event for analysis, and then filter the measured transients in order to obtain a reliable estimate of inertia for a given region of the GB network. The total inertia for the whole system is then calculated as a summation, with an estimate also provided as to the contribution to inertia from residual sources, namely synchronously connected demand and embedded generation. The approach is first demonstrated on the full dynamic model of the GB transmission system, before results are presented from analyzing the impact of a number of instantaneous transmission in-feed loss events using phase-angle data provided by PMUs from the GB transmission network and also devices installed at the domestic supply at 4 GB universities.
Das Wachstumssuppressorprotein p53, seine zellulären Partner und das Prostatakarzinom (1997)

Das Wachstumssuppressorgen p53 weist in mehr als 50% aller humanen Tumorerkrankungen genetische Veranderungen auf. Im Falle des Prostatakarzinoms sind solche genetischen Veranderungen und dadurch bedingt eine erhohte Expression des p53 Proteins spaten Stadien eines invasiven Prostatakarzinoms vorbehalten. Wildtyp p53 reguliert die Expression einer Vielzahl von zellularen Genen und bindet an zellulare regulatorische Proteine, so das man eine veranderte Interaktion von p53 mit zellularen Partnermolekulen in fruhen Stadien des Prostatakarzinoms in Betracht ziehen mus. So wurden bereits genetische Veranderungen im p21WAF1 Gen sowie Veranderungen in der Expression, subzellularen Lokalisation und Aktivitat der Proteinkinase CK2 beschrieben. Die CK2 bindet an p53, wodurch sowohl die Aktivitat der CK2 als auch des p53, reguliert wird. Wahrend p53 normalerweise mit immunhistochemischen Methoden im Zellkern nachgewiesen wird, findet man in der Prostatakarzinomzelle eine ungewohnliche subzellulare Lokalisation zumindest einer bestimmten immunologisch definierbaren Subklasse von p53, namlich im Nukleolus. Erste gentherapeutische Ansatze im Tiermodell weisen darauf hin, das durch Einbringen von Wildtyp p53 bzw. p21WAFl das Wachstum von Prostatakarzinomzellen unterdruckt werden kann. Alle diese Ergebnisse deuten darauf hin, das man fur die Diagnose, Prognose und Therapie des Prostatakarzinoms nicht nur p53, sondern auch seinen zellularen Partnern Beachtung schenken mus. The growth suppressor protein p53 is mutated in more than 50% of all human tumours. In prostate carcinoma genetic alterations and an elevated p53 protein expression seems to be restricted to late stages of invasive prostate carcinoma. Wild-type p53 regulates the expression of various cellular genes and it binds to an increasing number of cellular proteins. Binding to these proteins must be considered as playing a regulatory role in early stages of prostate carcinoma. Genetic alterations in the p21WAF1 gene and an altered expression, subcellular localization and enzymatic activity of protein kinase CK2 have been described for prostate carcinoma. The p21WAF1 gene is a downstream element of the p53 regulatory pathway. CK2 is a cellular p53 binding protein and by this interaction the enzymatic activity of CK2 as well as the DNA binding activity of p53 are regulated. p53 is usually detected in the nucleus by immunohistochemistry. However, in prostate carcinoma cells at least an immunologically defined subclass of p53 is found in the nucleoli. An initial gene therapeutic approach in an animal model revealed that wild-type p53 and p21WAF1 can inhibit the growth of prostate carcinoma cells. Hence, these results demonstrate that not only p53 but also its cellular partner molecules must be considered for the diagnosis, prognosis and therapy of prostate carcinoma.
Estrogen metabolism and the diet-cancer connection: rationale for assessing the ratio of urinary hydroxylated estrogen metabolites. (2002)

Estrogens are known for their proliferative effects on estrogen-sensitive tissues resulting in tumorigenesis. Results of experiments in multiple laboratories over the last 20 years have shown that a large part of the cancer-inducing effect of estrogen involves the formation of agonistic metabolites of estrogen, especially 16-alpha-hydroxyestrone. Other metabolites, such as 2-hydroxyestrone and 2-hydroxyestradiol, offer protection against the estrogen-agonist effects of 16-alpha-hydroxyestrone. An ELISA method for measuring 2- and 16-alpha-hydroxylated estrogen (OHE) metabolites in urine is available and the ratio of urinary 2-OHE/16-alpha-OHE (2/16-alpha ratio) is a useful biomarker for estrogen-related cancer risk. The CYP1A1 enzyme that catalyzes 2-hydroxyestrone (2-OHE1) formation is inducible by dietary modification and supplementation with the active components of cruciferous vegetables, indole-3-carbinol (I-3-C), or diindolylmethane (DIM). Other dietary components, especially omega-3 polyunsaturated fatty acids and lignans in foods like flax seed, also exert favorable effects on estrogen metabolism. Thus, there appear to be effective dietary means for reducing cancer risk by improving estrogen metabolism. This review presents the accumulated evidence to help clinicians evaluate the merit of using tests that measure estrogen metabolites and using interventions to modify estrogen metabolism.
A Crypt-Specific Core Microbiota Resides in the Mouse Colon (2012)

Metagenomic typing of the whole-gut luminal microbiome was recently provided, revealing great opportunities for physiological and physiopathological analysis of the host-microbiota interface. On this basis, it appears increasingly important to analyze which niches of the gut exposed to a particular microbiota are of major functional importance, specifically focusing on the crypt, which accounts for permanent epithelial renewal, and to analyze how this microbiota compares to its luminal counterpart in composition and quantity. Crypt-specific core microbiotas may show themselves as important elements regarding crypt protection and homeostasis of its functions.
CO <sub>2</sub> sequestration in basalt: Carbonate mineralization and fluid substitution (2011)

Basalt rocks contain some of the most reactive minerals when in contact with CO2‐water mixtures. The chemical reaction between minerals rich in calcium, magnesium and iron and carbonic acid precipitates carbonates in the pore space. This process would increase the elastic moduli and velocity of the rock. At the same time, the higher compressibility of CO2 over water changes the elastic properties of the rock, decreasing the saturated rock bulk modus and the P‐wave velocity. Reservoirs where the rock properties change as a result of fluid or pressure changes are commonly monitored with seismic methods. Here we describe experiments to study the feasibility of monitoring CO2 migration in a reservoir and CO2‐rock reactions for a sequestration scenario in basalts. Our goal is to measure the rock's elastic response to mineralization with non‐contacting ultrasonic lasers, and the effect of fluid substitution at reservoir conditions at seismic and ultrasonic frequencies.
Optical turbulence on underwater image degradation in natural environments (2012)

It is a well-known fact that the major degradation source on electro-optical imaging underwater is from scattering by particles of various origins and sizes. Recent research indicates that, under certain conditions, the apparent degradation could also be caused by the variations of index of refraction associated with temperature and salinity microstructures in the ocean and lakes. The combined impact has been modeled previously through the simple underwater imaging model. The current study presents the first attempts in quantifying the level of image degradation due to optical turbulence in natural waters in terms of modulation transfer functions using measured turbulence dissipation rates. Image data collected from natural environments during the Skaneateles Optical Turbulence Exercise are presented. Accurate assessments of the turbulence conditions are critical to the model validation and were measured by two instruments to ensure consistency and accuracy. Optical properties of the water column in the field were also measured in coordination with temperature, conductivity, and depth. The results show that optical turbulence degrades the image quality as predicted and on a level comparable to that caused by the particle scattering just above the thermocline. Other contributing elements involving model closure, including temporal and spatial measurement scale differences among sensors and mitigation efforts, are discussed.
A logic integrated optimal pin-count design for digital microfluidic biochips (2014)

Digital microfluidic biochips have become one of the most promising technologies for biomedical experiments. In modern microfluidic technology, reducing the number of independent control pins that reflects most of the fabrication cost, power consumption and reliability of a microfluidic system, is a key challenge for every digital microfluidic biochip design. However, all the previous chip designs sacrifice the optimality of the problem, and only limited reduction on the number of control pins is observed. Moreover, most existing designs cannot satisfy high-throughput demand for bioassays, and thus inapplicable in practical contexts. In this paper, we propose the first optimal pin-count design scheme for digital microfluidic biochips. By integrating a very simple combinational logic circuit into the original chip, the proposed scheme can provide high-throughput for bioassays with an information-theoretic minimum number of control pins. Furthermore, to cope with the rapid growth of the chip's scale, we also propose a scalable and efficient heuristics. Experiments demonstrate that the proposed scheme can obtain much fewer number of control pins compared with the previous state-of-the-art works.
Distinctive features, categorical perception, and probability learning: Some applications of a neural model. (1977)

A previously proposed model for memory based on neurophysiolo gical considerations is reviewed. We assume that (a) nervous system activity is usefully represented as the set of simultaneous individual neuron activities in a group of neurons; (b) different memory traces make use of the same synapses; and (c) synapses associate two patterns of neural activity by incrementing synaptic connectivity proportionally to the product of pre- and postsynaptic activity, forming a matrix of synaptic connectivities. We extend this model by (a) introducing positive feedback of a set of neurons onto itself and (b) allowing the individual neurons to saturate. A hybrid model, partly analog and partly binary, arises. The system has certain characteristics reminiscent of analysis by distinctive features. Next, we apply the model to categorical perception. Finally, we discuss probability learning. The model can predict overshooting, recency data, and probabilities occurring in systems with more than two events with reasonably good accuracy.