gebhart/patrepeval huggingface dataset:
Controllable Transformation from Rhombohedral Cu1.8S Nanocrystals to Hexagonal CuS Clusters: Phase- and Composition-Dependent Plasmonic Properties (2013)

Because of the rich polymorphs and lower diffusion energy barriers of copper chalcogenide systems, the phase transformation of colloidal Cu2–xS (0 ≤ x ≤ 1) nanocrystals is critical for understanding their fundamental properties and designing convenient synthetic routes. In this work, high quality digenite Cu1.8S nanocrystals with rhombohedral structure were synthesized at gram-scale. The as-prepared colloidal nanocrystals undergo an in situ phase transformation from rhombohedral Cu1.8S nanocrystals to hexagonal CuS clusters upon keeping the resulting colloidal solution for a few days. The observed transformation was explored by a combination of structural and spectroscopic analyses, including powder X-ray diffraction, transmission electron microscopy, energy dispersive spectroscopy, and X-ray photoelectron spectroscopy characterizations. A possible mechanism is proposed and thoroughly discussed. We further determined the evolution of plasmonic absorption spectra during the transformation. The Cu1.8S nanocrystals and CuS clusters exhibit composition-dependent local surface plasmon resonance absorption (LSPR) in the near-infrared region, which are in good agreement with calculated extinction spectra based on Mie-Drude model. Combined experimental and theoretical analyses demonstrated that both the phase induced dielectric constant change and the composition induced carrier concentration variation account for the spectroscopic evolution.
Decentralized Collaborative Load Transport by Multiple Robots (2006)

With the rapid progress of the robotic technology, it is becoming increasingly common to have multiple robots working together for material transport, cooperative assembly, etc. To ensure the proper handling of the load, especially if it is fragile or needs to be moved rapidly, the constraint force needs to be carefully managed. Tight force coordination is possible if all robots share their force information and the grasp geometry is completely known. When this is not the case, a common approach is to use the leader/follower strategy, where the leader provides the position control for the load and other robots comply based on the individual contact force measurements. This paper considers an alternate decentralized motion and force control method, where all robots participate in the control of the load without sharing any position and force information. Under centralized squeeze force control, robot motion is not affected. However, when the force control is decentralized, a perturbation term is added to the motion control loop. We show that the nominal exponential stability of the motion loop preserves the closed loop stability in the presence of this perturbation. Simulation and experimental results are included to demonstrate the proposed approach.
Direct observation of glycine metabolism in tobacco suspension cells by carbon-13 NMR spectroscopy (1984)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDirect observation of glycine metabolism in tobacco suspension cells by carbon-13 NMR spectroscopyDennis James Ashworth and Irvin Jacob MettlerCite this: Biochemistry 1984, 23, 10, 2252–2257Publication Date (Print):May 8, 1984Publication History Published online1 May 2002Published inissue 8 May 1984https://pubs.acs.org/doi/10.1021/bi00305a025https://doi.org/10.1021/bi00305a025research-articleACS PublicationsRequest reuse permissionsArticle Views44Altmetric-Citations10LEARN 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
ChemInform Abstract: An Expedient Route to the Calabar Bean Alkaloids (‐)‐Physovenine and (‐)‐Physostigmine. (2001)

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
TRAILER Project
(Tagging, Recognition, Acknowledgment of Informal Learning Experiences)
A Methodology to Make Learners' Informal Learning Activities Visible to the Institutions (2020)

García-Peñalvo, F. J., Conde, M. Á, Zangrando, V., García-Holgado, A., Seoane, A. M., Alier, M., Galanis, N., Brouns, F., Vogten, H., Griffiths, D., Mykowska, A., Ribeiro-Alves, G., &amp; Minović, M. (2013). TRAILER project (Tagging, recognition, acknowledgment of informal learning experiences). A Methodology to make visible learners’ informal learning activities to the institutions. Journal of Universal Computer Science, 19(11), 1661-1683. Available online http://www.jucs.org/jucs_19_11/trailer_project_tagging_recognition
Evapotranspiration Estimates for Deficit Irrigated Corn (2010)

Water deficits must be imposed on crops during non-critical growth periods to maximize net economic output per unit of water consumed by the plant. The reference ET-crop coefficient procedure widely used for managing fully irrigated crops would be easiest to implement for irrigation management of deficit irrigated crops provided the water stress coefficient (Ks) used in the procedure was more responsive to plant water stress. The objective of this paper was to further investigate the use of a canopy temperature (Tc) ratio calculated as a quotient of Tc measured over a fully irrigated crop divided by Tc measured over the water stressed crop as a substitute for Ks presently used in the reference ET-crop coefficient irrigation scheduling procedure. Four irrigation levels were imposed on corn (Zea mays L.) ranging from fully irrigated to 55% of seasonal ET applied at critical growth stages. Canopy temperature was continuously monitored in the four treatment levels and the Tc ratio was computed for the warmest period of the day (1300 to 1500 h MST). Crop ET was calculated solely as reference ET multiplied by the basal crop coefficient times the Tc ratio to estimate soil water deficit (SWD) with a water balance. This SWD estimate was compared to the SWD estimated by the traditional reference ET-crop coefficient-Ks procedure and measured SWD. The estimated SWD via the Tc ratio technique compared favorably with measured SWD for the 55% ET treatment. Advantages of this technique is that it does not require knowledge of soil water properties such as field capacity and total available water as well as the crop root depth.
SEE Sensitivity of a 16GHz LC-Tank VCO in a 22nm FinFET Technology (2022)

Voltage-controlled oscillators (VCOs) are essential components of frequency synthesizers used in space-based applications. Radiation in harsh space environments can cause SEEs (single-event effects) when a charged particle hits the silicon substrate and induces a transient current within the circuit that causes erroneous behavior. Hence, it is essential to understand the radiation sensitivity of a given process in order to design circuits that can tolerate these conditions. An LC-tank VCO is designed in a 22nm FinFET process and achieves 12.5-16.8GHz tuning range and −126dBc/Hz phase noise at a 10MHz offset from a 16.0GHz carrier. SEE sensitivity is quantified with a measured VCO maximum cross-sectional area of 350um <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> when testing with heavy ions with a linear energy transfer from 10 to 90 MeV.cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> /mg. These results are pertinent for future radiation-hardened VCO designs in this process.
Proteolytic Activity of Bacillus subtilis upon κ-Casein Undermines Its “Caries-Safe” Effect (2020)

Milk is believed to be a relatively "caries-safe" food. This belief relies on the fact that caseins, which constitute around 80% of milk's protein content, were found to inhibit the adhesion of <i>Streptococcus</i> <i>mutans</i> to enamel and, therefore, decrease biofilm formation. While <i>S.</i> <i>mutans</i> is considered a leading cause of dental disorders, <i>Bacillus subtilis</i> is a non-pathogenic foodborne bacterium, frequently contaminating milk and its products. This study aimed to investigate the effects of dairy-associated foodborne bacteria such as <i>B. subtilis</i> on biofilm formation by <i>S.</i> <i>mutans</i> in the presence of casein proteins. Our results indicate that there is a significant decrease in total biofilm formation by <i>S.</i> <i>mutans</i> exposed to a casein protein mixture in a mono-species culture, whereas, in the co-culture with <i>B. subtilis</i>, an inhibitory effect of the caseins mixture on <i>S.</i> <i>mutans</i> biofilm formation was observed. Proteolytic activity analysis suggested that <i>B. subtilis</i> is capable of breaking down milk proteins, especially κ-casein, which enables biofilm formation by <i>S.</i> <i>mutans</i> in the presence of milk caseins. Therefore, these findings may challenge the assumption that milk is "caries-safe", especially in a complex microbial environment.
Reduced-Order Modeling for Mesoscale Reactor Design (2018)

The following paper compares experiments with the performance of a simplified numerical model aimed at estimating surface temperatures of a mesoscale, combustion-driven, heat recirculating parallel channel reactor.Simplification is enabled by discretizing the domain of interest using a series of perfectly stirred reactors. This approach avoids the treatment of convective and diffusive transport and instead focuses on chemistry and heat transfer. An end user of the model is empowered to casually vary system parameters to satisfy a latent curiosity or as part of a larger parametric analysis, both of which are, otherwise, computationally expensive. Once designed, the reactor will serve as a heat source for a thermal-to-electrical energy convertor when coupled to a thermophotovoltaic receiver. All simulations are performed using Cantera: an open-source chemical kinetics library, which defines a set of abstracted forms to be used as building blocks to study the interaction between chemistry and heat transfer in a simplified geometry. The utility of this approach is demonstrated by assessing energy loss mechanisms through various surfaces, an impractical feat experimentally. The code developed as a part of this effort will be made available in an online repository.
Size-Controlled Synthesis of Sub-10-nanometer Citrate-Stabilized Gold Nanoparticles and Related Optical Properties. (2016)

Highly monodisperse, biocompatible and functionalizable sub-10-nm citrate-stabilized gold nanoparticles (Au NPs) have been synthesized following a kinetically controlled seeded-growth strategy. The use of traces of tannic acid together with an excess of sodium citrate during nucleation is fundamental in the formation of a high number (7 × 1013 NPs/mL) of small ∼3.5 nm Au seeds with a very narrow distribution. A homogeneous nanometric growth of these seeds is then achieved by adjusting the reaction parameters: pH, temperature, sodium citrate concentration and gold precursor to seed ratio. We use this method to produce Au NPs with a precise control over their sizes between 3.5 and 10 nm and a versatile surface chemistry allowing studying the size-dependent optical properties in this transition size regime lying between clusters and nanoparticles. Interestingly, an inflection point is observed for Au NPs smaller than 8 nm in which the sensitivity of the localized surface plasmon resonance (LSPR) peak position as a function of NPs size and surface modifications dramatically increase. These studies are relevant in the design of the final selectivity, activity and compatibility of Au NPs, especially in those (bio)applications where size is a critical parameter (e.g., biodistribution, multiplex labeling, and protein interaction).
High-efficiency GaInP∕GaAs∕InGaAs triple-junction solar cells grown inverted with a metamorphic bottom junction (2007)

The authors demonstrate a thin, Ge-free III–V semiconductor triple-junction solar cell device structure that achieved 33.8%, 30.6%, and 38.9% efficiencies under the standard 1sun global spectrum, space spectrum, and concentrated direct spectrum at 81suns, respectively. The device consists of 1.8eV Ga0.5In0.5P, 1.4eV GaAs, and 1.0eV In0.3Ga0.7As p-n junctions grown monolithically in an inverted configuration on GaAs substrates by organometallic vapor phase epitaxy. The lattice-mismatched In0.3Ga0.7As junction was grown last on a graded GaxIn1−xP buffer. The substrate was removed after the structure was mounted to a structural “handle.” The current-matched, series-connected junctions produced a total open-circuit voltage over 2.95V at 1sun.
El Voltímetro Digital Y La Comparación A Partir De Transistores (2011)

Se desarrollo un sistema para describir y explicar cabalmente el principio fisico del voltimetro digital a partir de los conceptos fundamentales de comparacion, interruptor, balanceo y estado discreto. El sistema permite hacer una analogia estructural entre la medicion con una balanza mecanica y la medicion de la tension electrica con este voltimetro basico. El voltimetro esta basado en un circuito comparador conformado por dos transistores acoplados por emisor comun (amplificador diferencial), que tiene como funcion comparar una tension de prueba con una tension de referencia. La tension de referencia es la magnitud de la unidad de medida discreta. Se obtuvo un voltimetro elemental que permite al estudiante de fisica basica hacer inferencia analogica sobre otros procesos de medicion de cantidades electromagneticas como especular formalmente sobre nuevas estructuras de medicion. We developed a system to fully describe and explain the physical principle of the digital voltmeter from the fundamental concepts of comparison, switch, balancing and discrete state. The system allows a structural analogy between the measurement with a mechanical balance and the electrical voltage measurement with a basic voltmeter. The voltmeter is based on a comparator circuit composed of two common-emitter-coupled transistors (differential amplifier), which has the function of comparing a test voltage with a reference voltage. The reference voltage is the magnitude of the discrete unit of measure. The result was a basic voltmeter that allows the student of basic physics to make analogy inferences about other processes of measuring of electromagnetic quantities and to formally speculate on new measurement structures.
Monolithic Integration of Vertical Cavity Surface Emitting Laser and Diffractive Optical Element for Advanced Beam Shaping (2005)

We have demonstrated a vertical-cavity surface- emitting laser (VCSEL) with a monolithically integrated diffrac- tive optical element (DOE) for advanced beam shaping. The DOE is a two-level surface relief, etched into the GaAs substrate beneath a bottom-emitting VCSEL. The combination generates a4 4 array of focused spots 10 mm from the substrate with spot sizes down to less than 400 m, almost at the diffraction limit. Diffraction efficiencies of 29% and uniformity errors of 14% were measured.
Prediction of response to IVIg treatment in patients with lower motor neurone disorders (2006)

The distinction between multifocal motor neuropathy, treatable by intravenous immunoglobulins (IVIg), and degenerative motor neurone disorders is often difficult. To find predictive factors for the response to IVIg treatment, 40 consecutive patients with pure lower motor neurone disorders (LMND) were prospectively examined. They all received at least two times IVIg (2 g/kg bodyweight). Prior to the first and before all the following treatments a standardized evaluation was performed including clinical examination, neurophysiological and laboratory evaluation. According to changes in the neurological examination and the Neuromuscular Symptom Score, the patients were divided into responders and non-responders after the second course of treatment. In our study, no single clinical, neurophysiological, or laboratory parameter was sensitive enough to predict response. The only single parameter that highly correlated with a positive response to treatment was an elevated GM1 antibody titre. Lack of response to IVIg treatment is likely in patients with generalization of electromyographic signs of denervation beyond the clinically involved site, proximal localization of the weakness, and an elevated level of the creatinekinase. Conduction blocks do not distinguish between both groups. We propose a scoring system combining clinical, serological and neurophysiological data in order to decide which patients with LMND may receive IVIg.
Nucleosides. 125. Synthesis of 5'-deoxy-5'-substituted-1,3-dimethyl-psi-uridines from 3',5'-O-(1,1,3,3-tetraisopropyldisiloxanyl)-1,3-dimethyl-psi-uridine. A novel isomerization reaction. (1982)

Treatment of 3'-5'-O-(1,1,3,3-tetraisopropyldisiloxanyl)-1,3-dimethyl-psi-uridine (7) . with one equivalent of base and a slight excess of trifluoromethanesulfonic anhydride afforded 5'-O-trifluoromethanesulfonyl-2',3'-O-(1, 1,3,3-tetraisopropyldisiloxanyl)-1,3-dimethyl-psi-uridine (8). Nucleophilic displacement of the 5'-trifluoromethanesulfonyloxy group by treatment with various alkali metal salts of halide, azide, or acetate followed by deprotection by fluoride ion treatment afforded the corresponding 5'-substituted-1, 3-dimethyl-psi-uridine derivatives (10) in good yields in crystalline form.
Diosgenin-induced biliary cholesterol secretion in mice requires Abcg8 (2005)

The plant sterol diosgenin has been shown to stimulate biliary cholesterol secretion in mice without affecting the expression of the adenosine triphosphate-binding cassette transporter heterodimer Abcg5/g8. The aim of this study was to investigate the mechanism of diosgenin-induced cholesterol hypersecretion and to identify the genes involved. Surprisingly, despite its lack of effect on Abcg5/g8 expression in wild-type mice, diosgenin did not stimulate biliary cholesterol secretion in mice deficient for Abcg8. Analysis of the kinetics of cholesterol secretion suggested that diosgenin probably activates a step before Abcg5/g8. To identify potential diosgenin targets, gene expression profiling was performed in mice fed a diosgenin-supplemented diet. Diosgenin feeding increased hepatic expression of genes involved in cholesterol synthesis as well as genes encoding for several cytochrome P450s. No significant change in expression of known cholesterol transporters was found. Comparison with published expression-profiling data for Srebp2-overexpressing mice, another mouse model in which biliary cholesterol secretion is elevated, revealed a number of genes with unknown function that were upregulated in both diosgenin-fed mice and mice overexpressing Srebp2. In conclusion, we found that although Abcg8 is essential for most diosgenin-induced biliary cholesterol hypersecretion, diosgenin probably does not interact directly with Abcg5/Abcg8, but rather increases cholesterol delivery to the heterodimer. Supplementary material for this article can be found on the HEPATOLOGY website (http://interscience.wiley.com/jpages/0270-9139/suppmat/index.html).
The Blood-Testis Barrier in the Rat and the Physiological Compartmentation of the Seminiferous Epithelium1 (1970)

Previous work has indicated that the contractile “myoid cells” surrounding the seminiferous tubules serve as a barrier to the penetration of substances into the germinal epithelium. In the present study, the nature of the junctions separating myoid cells was investigated with en bloc uranyl acetate staining and with lanthanum nitrate, a small electron-opaque tracer useful for testing the patency of junctions. While some of the junctional complexes exhibited a continuous interspace of 200 Å, the majority displayed occluding junctions which effectively prevented passage of perfused lanthanum into the germinal epithelium. However, in 10–15% of the cross sections of tubules examined, lanthanum did penetrate the myoid cell layer through open junctions. At these sites the tracer also entered the interspaces between the Sertoli cells and the spermatogonia clearly outlining the latter. The interspaces between the spermatogonia and the Sertoli cells are continuous with those separating adjacent Sertoli cells, but the tracer was only able to penetrate for short distances further toward the tubular lumen. High magnification electron microscopy revealed that tight junctions connected adjacent Sertoli cells a short distance from the spermatogonia. Thus, while the myoid cells constitute a significant permeability barrier, the tight junctions between Sertoli cells form a second, and apparently a more effective barrier to the penetration of substances through the germinal epithelium. These results indicate that in the seminiferous tubules two compartments are formed by the Sertoli cells and their junctional complexes: (1) a basal compartment between the Sertoli junctions and the basal lamina, containing the spermatogonial population and early preleptotene spermatocytes, and (2) an adluminal compartment above the Sertoli junctions, containing the other germ cells. The possible functional significance of the barrier at the level of the peritubular contractile cells and of the compartmentalization of the seminiferous epithelium is discussed.
FPGA-Based PWM Implementation of Matrix Converter in Inductive Wireless Power Transfer Systems (2018)

This paper presents the design and implementation of a digital carrier-based pulse width modulation (PWM) generator for matrix AC-AC converter in inductive power transfer (IPT) systems using field-programmable gate array (FPGA). The design consumes a small fraction of the hardware resource of a medium-sized FPGA, and can be then incorporated as a part of a large control unit in IPT applications. The PWM generator is developed on a SmartFusion ARM-based mixed-signal FPGA controller, and experimental verifications have been given to illustrate the performance of the proposed PWM generator.
Body surface estimation: a critical evaluation (2002)

Estimates of body surface area (BSA) are widely used in intensive care, cancer chemotherapy, anesthesia, hemodialysis and other critically important medical computations. Although formulas have been proposed, virtually all BSA estimates use a formula promulgated in 1916 based on a sample of twelve possibly atypical subjects. The inclusion of a computation into a computer program imparts the impression of accuracy which is not always justified. The authors have attempted to examine and compare some direct measurement methods and estimation formulas used for BSA particularly with respect to inter-method consistency and correlation with a variety of published data.