gebhart/patrepeval huggingface dataset:
ChemInform Abstract: A Dual‐Function, Highly Efficient Chiral Controller for Stereoselective Intermolecular Pauson‐Khand Reactions. (1994)

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.
Room-temperature Tm, Ho:LuLiF_4 laser with a novel quasi-end-pumping technique (2001)

A novel diode-pumped, efficient, quasi-end-pumping scheme that uses two lens ducts to achieve homogeneous pumping in a gain medium was proposed and evaluated. With this technique, room-temperature laser action at a pulse repetition frequency up to 20 Hz was demonstrated in 5%Tm, 0.5%Ho:LuLiF(4), which we grew by the Czochralski method. At 10 Hz a long-pulse laser output energy in excess of 24 mJ and a slope efficiency with respect to the incident pump energy of 10.7% were obtained.
Concise and Practical Synthesis of <i>C</i>-Glycosyl Ketones from Sugar Benzothiazoles and Their Transformation into Chiral Tertiary Alcohols (2005)

[Reaction: see text]. A collection of 13 unsymmetrical ketones, each one featuring a sugar (d-glucosyl, d-galactosyl, d-mannosyl, and l-fucosyl) and an aglycone moiety (phenyl, 2-thiazolyl, TMS-ethynyl, allyl, and 1-propenyl) was prepared by a uniform route based on the use of benzothiazole as a carbonyl group equivalent. Succinctly, C-glycosylbenzothiazoles readily prepared by addition of 2-lithiobenzothiazole to sugar lactones and deoxygenation, were subjected to a one-pot reaction sequence involving N-methylation of the heterocyclic ring by MeOTf, treatment of the N-methylbenzothiazolium salt with a Grignard reagent, and HgCl(2)-promoted hydrolysis of the benzothiazoline thus formed. The resulting ketones were isolated in yields varying from 35 to 80%. Treatment of the sugar ketones with various organometals containing the phenyl, 2-thiazolyl, TMS-ethynyl, or ethynyl group as a substituent afforded chiral tertiary alcohols. These addition reactions were highly stereoselective as observed by crude NMR analysis and isolation of a single epimer in high yield in each case examined. However, because of the complexity of the reagents involved, the stereochemical outcome of these reactions appears to be difficult to rationalize by simple classical steric models, thus, ab initio studies taking into account the role of the sugar fragment are advisable. An interesting synthetic elaboration of a propargylic alcohol containing the thiazole ring into a propargylic alcohol bearing the formyl and carboxylate groups is reported.
Single FPGA-based optimization of MVB universal interface (2011)

In order to expand compatibility of on-board, on-board with out-board equipments, and improve capacity of data exchange between MVB(Multifunction Vehicle Bus) and other external buses, it used a single FPGA to realize the universal interface in which both the MVB interface and other variety of communication bus interfaces are included. It used ARM to load multiple-communication protocols upon FPGA automatically. For influence of high frequency noises and signal synchronous slip, transmission signal waveforms existed certain degree of nonlinear distortion, which would cause data transmission failure in the worst case. To avoid those cases, the interface adopted an nonlinear signal discretization compensation strategy. The real time dynamic compensations were calculated each cycle by a high speed digital controller. The final test results show that it is feasible for a single FPGA realizing universal interface function of communication, and after compensation the signal waveforms gain great improvement.
Experimental Discussion on Duty Ratio Obtaining Higher Efficiency for Cascaded Three-stage Boost Converter for Fuel Cells (2018)

Fuel cell (FC) is a clean power source and does not emit CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> at its electric power generation. In recent years, low voltage and large current type FC stack is becoming popular in some applications. Thus, a DC/DC converter with the high voltage-boost ratio for such FC stack is required and several types of converters have been researched. As one of such DC/DC converters with the high voltage-boost ratio, there is a cascaded three-stage boost converter. In this converter, it is necessary to consider the combinations of duty ratios which can obtain higher efficiency with respected to change in FC output voltage. Therefore, the efficiency characteristics of the cascaded boost converter are clarified by experiments. In an actual system, there are some losses such as switching losses and the copper losses in the inductors and the capacitors. In addition, 1st stage duty ratio d <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> was set to 0.5 in order to obtain minimum input current ripple. Therefore, the duty ratios of 2nd and 3rd stage converters must be set larger value than the theoretical value. In the experiments, power conversion efficiencies were measured for each combination of the duty ratios. As a result, in order to obtain high power conversion efficiency, it is preferable that the duty ratio d <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> in the 2nd stage converter is larger while the duty ratio d <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> in the 3rd stage converter is smaller.
Polymerizable Vancomycin Derivatives for Bactericidal Biomaterial Surface Modification: Structure−Function Evaluation (2009)

Surface modification of implantable biomaterials with biologically active functionalities, including antimicrobials, has wide potential for addressing implant-related design problems. Here, four polymerizable vancomycin derivatives bearing either acrylamide or poly(ethylene glycol) (PEG)-acrylate were synthesized and then polymerized through a surface-mediated reaction. Functionalization of vancomycin at either the V(3) or the X(1) position decreased monomeric activity by 6-75-fold depending on the modification site and the nature of the adduct (P < 0.08 for all comparisons). A 5000 Da PEG chain showed an order of magnitude decrease in activity relative to a 3400 Da counterpart. Molecular dynamics computational simulations were used to explore the mechanisms of this decreased activity. Assays were also conducted to demonstrate the utility of a living radical photopolymerization to create functional, polymeric surfaces with these monomers and to demonstrate surface-based activity against Staphylococcus epidermidis . In particular, the vancomycin-PEG-acrylate derivatives demonstrated a 7-8 log reduction in bacterial colony forming units (CFU) with respect to nonfunctionalized control surfaces.
Versatile Flow-Injection Amperometric Ion Detector Based on an Interface between Two Immiscible Electrolyte Solutions: Numerical and Experimental Characterization (2011)

The present paper describes a flexible thin layer electrochemical flow cell for ultrasensitive amperometric detection at a supported interface between immiscible electrolyte solutions. Nanomolar detection limits were demonstrated using the cell design, and 3D finite element simulations allowed a detailed characterization of the flow cell. The cell design employed in the present work allowed the sensing oil membrane and the aqueous reference electrode to be placed in close contact, thereby minimizing cell resistance. The adjustable cell volume means that the same cell design can be used for different application with different requirement for detection limits and dynamic range. A disposable membrane was employed which reduces the need for surface cleaning and prevents sample carryover between different applications. For the lowest cell volumes the detection chamber approaches a thin layer electrochemical flow cell detector with a large surface to volume ratio.
Differential Semimajor Axis Estimation Performance Using Carrier-Phase Differential Global Positioning System Measurements (2007)

This paper investigates the impact of navigation errors on the navigation and control aspects of formation flying spacecraft. The use of carrier-phase differential Global Positioning System measurements in relative navigation filters is analyzed, with a particular focus on the semimajor axis error. Semimajor axis error is shown to be the sum of two positive quantities that are related to the satisfaction of the balance and correlation requirements. Previous publications have suggested that a good navigation filter would yield estimates of the along-track velocity and radial position that are strongly correlated. However, practical experience with filters based on the carrier-phase differential Global Positioning System measurements has shown that this seldom occurs, even when the estimation accuracies are very good. Analytical methods and numerical simulations are used to show that the optimal semimajor axis estimate from a Kalman filter does not satisfy these requirements for any combination of measurement and process noise. Numerical examples with a fully nonlinear extended Kalman filter appear to bear out these conclusions. The combination of these simulations and analysis provides new insights on the crucial role of the process noise in determining semimajor axis knowledge.
Ionic Strength Dependent Transport of Microparticles in Saturated Porous Media: Modeling Mobilization and Immobilization Phenomena under Transient Chemical Conditions (2009)

This study investigates ionic strength dependent deposition and release of microparticles in saturated porous media. Controlled micrometer-sized particle deposition experiments were conducted, followed by stepwise modifications in porewater chemistry to induce retained particle mobilization. A transient dual site transport model was tested against deposition and release, systematically addressing the effect of variations in solution ionic strength by coupling the equations for colloid transport with that for solute transport. The attachment and detachment coefficients of the model equations were explicitly tied to the salt concentration through proposed empirical functions, derived from experimental and theoretical considerations. Two regimes of attachment (and detachment) were hypothesized, showing favorable behavior beyond modeled values of a critical deposition concentration (and critical release concentration). Blocking phenomena were accounted for as well. This work shows how the intimate inclusion of salt concentration in a unique model equation system is able to describe both deposition and release behaviors of the particles under transient chemical conditions.
Evaluating the value of continuing docetaxel and prednisone (DP) beyond 10 cycles in men with metastatic castration-resistant prostate cancer (mCRPC). (2011)

4582 Background: The optimal number of cycles of 3-weekly DP therapy for mCRPC has not been ascertained. An exploratory analysis was conducted comparing results of 335 men on the DP arm of the TAX-327 study, which limited chemotherapy to 10 cycles, and a recently completed randomized clinical trial of 221 men allocated to either DP+AT-101 (bcl-2 inhibitor) versus DP+placebo, which allowed up to 17 cycles of DP. Methods: Patients who initiated cycle 10 of therapy without progression in both studies were included. Per protocol, men on the TAX-327 study received 1 additional cycle, while men on the AT-101 study received up to cycle 17. Men in both arms of the AT-101 study were combined for analysis, as no significant differences in outcomes were observed. Overall survival (OS) was estimated from the cycle 10 D infusion date, using the Kaplan-Meier method. Results: The number of men receiving cycle 10 cycle was similar (Fisher's exact test p-value=0.60) between the two studies (166 or 49.6% in the TAX-327 study versus 99 or 44.8% in the AT-101 study), though of these men, death date information was more complete due to longer follow-up in TAX-327 (79.5% versus 34.4%). Six- and 12-month estimated survival from cycle 10 was 92.2% (95% CI: 86.9-95.4%) and 74.6% (CI: 67.2-80.5%) for TAX-327 patients, compared with 92.8% (CI: 85.5-96.5) and 63.4% (CI: 51.8-72.9%) for those on AT-101. Survival statistics were similar beyond cycle 10 within good, intermediate and poor risk groups. 38 (38.4%) men on the AT-101 study completed all 17 cycles. Of men on the AT-101 study, 24 and 13 had consistently declining PSA through cycles 13 and 17. Conclusions: A survival benefit was not detected with more than 10 cycles of DP chemotherapy in men with mCRPC in this hypothesis-generating exploratory analysis. A subset of men with mCRPC continue to have declines in PSA up to cycle 17 and thus may have ongoing benefit to continued chemotherapy administration. However, a randomized clinical trial is necessary to establish the optimal duration of therapy.
Effects of background fluorescence in fluorescence molecular tomography (2005)

Recent advances in optical imaging systems and systemically administered fluorescent probes have significantly improved the ways by which we can visualize proteomics in vivo. A key component in the design of fluorescent probes is a favorable biodistribution, i.e., localization only in the targeted diseased tissue, in order to achieve high contrast and good detection characteristics. In practice, however, there is always some level of background fluorescence present that could result in distorted or obscured visualization and quantification of measured signals. In this study we observe the effects of background fluorescence in tomographic imaging. We demonstrate that increasing levels of background fluorescence result in artifacts when using a linear perturbation algorithm, along with a significant loss of image fidelity and quantification accuracy. To correct for effects of background fluorescence, we have applied cubic polynomial fits to bulk raw measurements obtained from spatially homogeneous and heterogeneous phantoms. We show that subtraction of the average fluorescence response from the raw data before reconstruction can improve image quality and quantification accuracy as shown in relatively homogeneous or heterogeneous phantoms. Subtraction methods thus appear to be a promising route for adaptively correcting nonspecific background fluorochrome distribution.
Specificity and mechanism(s) of promoter inhibitors in multistage promotion. (1982)

The mouse skin system was used as a model for the study of multistep chemical carcinogenesis and for bioassaying carcinogenic agents. The tumor initiating and promoting activities of various compounds were determined as well as whether the agent is a complete carcinogen. (ACR)
Prognostic value of the histochemical expression of Helix pomatia agglutinin in advanced colorectal cancer (1994)

Histochemical expression of helix pomatia agglutinin will indeed aid in accurately predicting the prognosis of patients with advanced colorectal cancer.
A New Active 3D Optical Proximity Sensor Array and its Readout Circuit (2014)

A new 3-D proximity sensor panel (3-D touch panel) for a single object is proposed in this paper. The sensor panel consists of a photo detector (PD) array as active pixels, along with its optics design, a computation algorithm, and sensing circuitry to eliminate background lighting. This sensing panel system acts as a noncontact 3-D positioning sensor, which is able to sense spatial positions of the object without realistic touching to the panel. New active readout pixel circuits for the PDs are designed to efficiently convert PD-received light intensities to voltage signals. It offers high readout resolutions, larger output ranges, and lower noises, as compared with the conventional active pixel sensor (APS) with a 3T-structure (called 3T-APS). Toward success of the sensor, background light is eliminated by a specially designed sample and hold circuitry, whereas a computation algorithm for 3-D object detection is developed based on photometry. The circuit is fabricated by Taiwan Semiconductor Manufacturing Company 0.35-μm 2P4M 3.3 V mixed signal CMOS process. Sensing trials for a moving object are finally conducted. The sensor performance is validated and further illustrated by a Labview program. The sensing errors of a sphere object are successfully limited to 5% in percentages.
A Two-Dimensional Protein Gel Electrophoresis Study of the Heat Stress Response of <i>Bacillus subtilis</i> Cells during Sporulation (2000)

The heat resistance of spores of Bacillus subtilis formed at 30 degrees C was enhanced by pretreatment at 48 degrees C for 30 min, 60 min into sporulation, for all four strains examined. High-resolution two-dimensional gel electrophoresis showed the generation and/or overexpression of 60 proteins, 11 of which were specific to heat shock, concurrent to this acquired thermotolerance. The greatest number of new proteins was observed between 30 and 60 min after heat shock, and the longer the time between exponential growth and heat treatment, the fewer differences were observed on corresponding protein profiles. The time at which heating produced the maximum increase in spore resistance and the most new proteins on two-dimensional gels occurred before alkaline phosphatase and dipicolinic acid production and corresponded to stage I or II of sporulation. The stress proteins formed disappeared later in sporulation, suggesting that heat shock proteins increase spore heat resistance by altering spore structure rather than by repairing heat damage during germination and outgrowth.
Major New Developments in Hydraulic Fracturing, with Documented Reductions in Job Costs and Increases in Normalized Production (1994)

Abstract A number of developments over the past five years have led to dramatic changes in the design and execution of hydraulic fracturing treatments. Five primary new issues are described: convection, tortuosity, rock/fracture (non-linear) response, appropriate use of rheology/flow-rate and permeability variation effects. Consequences include "paradigm shifts", such as inverse relations between appropriate proppant concentration and reservoir permeability. Resulting integrated cost-effective and rewarding methodologies for fracture execution are emphasized and the methodology is illustrated with just a few case-studies, selected to emphasize a variety of technical features as against absolutely optimum execution. Suitable generic implementation and procedures, using greatly reduced fluid volumes, are outlined in sufficiently general form to allow (practically optimum) job execution on any well, particularly in low-permeability reservoirs. The variation between (nominally identical) wells, and the vital role of real-time analysis for on-site execution of adequate jobs, is demonstrated - including unique (but essential) representation of realistic/general physics in the models used to interpret adequate data-sets. The case-studies serve to illustrate the major issues, including many ancillary features involved in proper interpretation of pressure/flow data before, during and after fracturing treatments: it is emphasized here (and in a companion paper for higher permeability) that the proper/sensible combination of all freely-collectible data, including long-term production plots, which should be a natural part of all well operations, usually leads to (practically) unique interpretation of reservoir conditions and job effectiveness: good reservoirs are properly identified and poor-success cannot be so easily ascribed to poor kH. Well procedures and costs are thereby adapted to (optimum) production.
On file-based content distribution over wireless networks via multiple paths: Coding and delay trade-off (2011)

With the emergence of the adaptive bit rate (ABR) streaming technology, the video/content streaming technology is shifting toward a file-based content distribution. That is, video content is encoded into a set of smaller media files containing video of 2–10 seconds before transmission. This file-based content distribution, coupled with increasingly rapid adoption of smartphones, requires an efficient file-based distribution algorithm to satisfy the QoS demand in wireless networks. In this paper, we study the transmission of a finite-sized file over wireless networks using multipath routing, with the objective to minimize file transmission delay instead of average packet delay. The file transmission delay is defined as the time interval from the instant that a file is first transmitted to the time at which the file can be reconstructed in the destination node. We observe that file transmission delay depends not only on the mean of the packet delay but also on its distribution, especially the tail. This observation leads to a better understanding of the file transfer delay in wireless networks and a minimum delay file transmission strategy. In a wireless multipath communication scenario, we propose to use packet level erasure code (e.g., digital fountain code) to transmit data file with redundancy. Given that a file with k packets is encoded into n packets for transmission, the use of digital fountain code allows the file to be received when only k out of n packets are received. By adding redundant packets, the destination node does not have to wait for the packet to arrive late, hence reducing the delay of the file transmission. We characterize the tradeoff between the code rate (i.e., the ratio of the number of transmitted packets to the number of the original packets) and the file delay reduction. As a rule of thumb, we provide practical guidelines in determining an appropriate code rate for a fixed file to achieve a reasonable transmission delay. We show that only a few redundant packets are needed to achieve a significant reduction in file transmission delay.
Laser Microtexturing of Implant Surfaces for Enhanced Tissue Integration (2000)

Abstract Dental and orthopaedic implants rely on combinations of bone and soft tissue integration for mechanical support. While polished metal surfaces have been shown to encourage fibrous tissue encapsulation, roughened surfaces encourage bone integration. It is an accepted practice to roughen or texture regions of implants to encourage bone integration and produce smooth regions to promote soft tissue integration. We have developed a laser microtexturing technique that can be used to produce precision microtextured surfaces.
The spontaneous self-organization of an adaptive language (2000)

Abstract The paper studies how a group of distributed agents may spontaneously and autonomously develop a language to refer to other agents in their environment by engaging in a series of language games. The language is adaptive in the sense that it expands or adjusts to the entry of new agents and new meanings. The paper describes the language formation mechanisms and details the results of computational simulations. The paper proposes a set of mechanisms by which a group of distributed agents may develop autonomously a language for identifying other agents in their environment. The set of agents and the set of features used for making distinctions is open-ended. The language autonomously adapts by the individual actions of agents with only local interactions.
Resistance of Stainless Alloys to Dilute Sulfuric Acid (2011)

Abstract Corrosion data have been generated in dilute sulfuric acid solutions for a wide variety of stainless alloys. Most data have been generated at atmospheric boiling temperature (~100°C), with limited testing at 80°C to provide an indication of temperature sensitivity. Data have been generated in solutions of 0.5 to 20% concentration to produce data that help define the 0.10 mm/a (4 mils/year) corrosion resistance threshold. Materials investigated range from lean duplex stainless steels to highly alloyed NiCrMo materials.