gebhart/patrepeval huggingface dataset:
Characterization of Fluorescent, Unnatural Base Pairs. (2007)

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Microchannel plate intensifier gain uniformity improvement in sealed tubes by selective scrubbing (1993)

We have improved the gain uniformity of sealed microchannel plate image intensifiers (MCPIs) by selectively scrubbing the high gain sections with a controlled bright light source. The major contributor to poor uniformity on most of the tubes we have tested is the cathode, with the MCP and screen making only minor contributions. Using the premise that ions returning to the cathode from the MCP damage the cathode and reduce its sensitivity, we raster scanned an HeNe laser beam light source across the cathode of an MCPI tube. Cathode current was monitored and when it exceeded a preset threshold, the sweep rate was decreased 1000 times, giving 1000 times the exposure to cathode areas with sensitivity greater than the threshold. The threshold was set at the cathode current corresponding to the lowest sensitivity in the active cathode area so that sensitivity of the entire cathode would be reduced to this level. This process reduced tube gain by between 10% and 30% in the high gain areas while gain reduction in low gain areas was negligible. Effects on cathode spectral sensitivity and phosphor efficiency, the results of including the MCP in the feedback loop, the possibility of reclaiming tubes damaged by prolonged exposure to resolution targets, and circuit details are discussed.
Achieving Economic Operation and Secondary Frequency Regulation Simultaneously Through Local Feedback Control (2016)

This paper presents an exciting finding for the power industry: The parameters of secondary frequency control based on integral or proportional integral control can be tuned to achieve economic operation and frequency regulation simultaneously within a considerable short period. We show that if the power imbalance is represented by frequency deviation, an iterative dual-ascent-based economic dispatch solving is equivalent to integral control. An iterative method of multipliers based economic dispatch is equivalent to proportional integral control. Similarly, if the controller parameters of the secondary frequency controls are chosen based on generator cost functions, these secondary frequency controllers achieve both economic operation and frequency regulation simultaneously.
Amphiphilic Networks (1991)

Amphiphilic networks comprising poly(N,N-dimethylacrylamide) (PDMAAm) linked (1) by polyisobutylene (PIB) segments have been synthesized by the radical copolymerization of DMAAm and narrow molecular weight (Mw/Mn ~ 1.1) distribution methacrylate-telechelic PIB macromonomers (MA-PIB-MA). Conditions have been optimized for the preparation of various PDMAAm-1-PIB networks of good mechanical properties. DSC traces exhibit a high and a low temperature Tg (i.e., from 90 to 115 °C and from -52 to -63°C, respectively) which indicates microphase separation into PDMAAm and PIB domains. The amphiphilic and co-continuous nature of PDMAAm-1-PIB networks was demonstrated by swelling both in water and n-heptane. Drug delivery devices were prepared by loading theophylline into tough flexible PDMAAm-1-PIB networks and studying the release of this material into water. Release studies indicate sustained drug release and kinetics controlled by combination of the Mn of the PIB segments and the PIB content.
Experimental demonstration of the p-ring FS&#x002B; Trench IGBT concept: A new design for minimizing the conduction losses (2015)

A new IGBT type structure, namely the p-ring FS+ Trench IGBT, with improved performance has been demonstrated. The improvement has been achieved through the utilization of p doped buried layers (p-rings) which allows for the simultaneous increase in the n enhancement layer doping concentration above the conventional levels without compromising the device breakdown rating. This unique lateral charge compensation approach is demonstrated to be highly effective in lowering the on-state losses. The experimental results show a 20% reduction in the on-state losses for a 1.7kV device.
Linearly chirped fiber-optic Bragg grating as distributed temperature sensor for laser ablation (2016)

We report a novel technique for estimating spatially distributed temperature profile, with a linearly chirped fiber Bragg grating (LCFBG) fiber-optic sensor, and its application in laser ablation of tissue. Our algorithm determines the temperature profile from LCFBG optical spectrum with sub-0.1mm resolution; a spectral flattening filter compensates for LCFBG spectral ripples, allowing operation with commercial gratings. A preliminary experimental analysis on LCFBG monitoring laser ablation of porcine liver has been carried out.
Electroactive Tissue Scaffolds with Aligned Pores as Instructive Platforms for Biomimetic Tissue Engineering (2015)

Tissues in the body are hierarchically structured composite materials with tissue-specific chemical and topographical properties. Here we report the preparation of tissue scaffolds with macroscopic pores generated via the dissolution of a sacrificial supramolecular polymer-based crystal template (urea) from a biodegradable polymer-based scaffold (polycaprolactone, PCL). Furthermore, we report a method of aligning the supramolecular polymer-based crystals within the PCL, and that the dissolution of the sacrificial urea yields scaffolds with macroscopic pores that are aligned over long, clinically-relevant distances (<i>i.e</i>., centimeter scale). The pores act as topographical cues to which rat Schwann cells respond by aligning with the long axis of the pores. Generation of an interpenetrating network of polypyrrole (PPy) and poly(styrene sulfonate) (PSS) in the scaffolds yields electroactive tissue scaffolds that allow the electrical stimulation of Schwann cells cultured on the scaffolds which increases the production of nerve growth factor (NGF).
Design and study of aqueous processable positive-tone photoresists (2000)

Interest in developing materials with reduced environmental impact has led us to design resist formulations that can be cast from and developed with aqueous media. A water soluble chemically amplified positive tone photoresist based on thermal decarboxylation of a half ester of malonic acid has been designed. Two solubility switches are required for this application. Sequential volatilization of ammonia followed by decarboxylation of a malonic acid gives the first solubility switch and an acid catalyzed thermolysis of an acid labile protecting group gives the second. The thermal stability of the acid labile protecting group is critical in this design. Tert-butyl esters decompose during the decarboxylation process resulting in poor imaging contrast. Polymers bearing isobornyl esters are more thermally stable, and show excellent reaction selectivity between the decarboxylation and the thermolysis of the ester. Preliminary imaging of this system provided 1 micrometer resolution with 248 nm exposure and standard TMAH developer. The dry etch stability of the photoresist films is comparable to a conventional photoresist APEX-E<SUP>R</SUP>.
Effectiveness of thyristor controlled series capacitor in enhancing power system dynamics: an analog simulator study (1994)

Simulator tests of a new type of series capacitor, controlled by thyristor switches, are described. The structure of the control system and the components of the real-time simulator used for the tests are presented. Test results show performance for switching transients, AC faults, power-swing damping events, and subsynchronous resonance conditions. The thyristor controlled series capacitor is part of an EPRI sponsored project connected with flexible AC transmission systems.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Gallium nitrate inhibits calcium resorption from bone and is effective treatment for cancer-related hypercalcemia. (1984)

Approximately two-thirds of patients who receive the anticancer drug gallium nitrate develop mild hypocalcemia. To evaluate the mechanism of drug-induced hypocalcemia, we tested the effects of gallium nitrate upon in vitro release of 45Ca++ from explanted fetal rat bones. The drug significantly inhibited 45Ca++ release in response to stimulation with both parathyroid hormone and a lymphokine preparation with osteoclast activating factor activity. The inhibitory effects on bone resorption were both time- and dose-dependent. Later, in a pilot study, we treated 10 patients who had cancer-related hypercalcemia with gallium nitrate administered by continuous infusion. All patients responded by a reduction of total serum calcium to normal or subnormal concentrations (13.8 +/- 1.05 mg/dl, mean +/- SD pretreatment, to 8.03 +/- 1.03 mg/dl, mean posttreatment nadir). Our results indicate that gallium nitrate effectively treats cancer-related hypercalcemia and that it probably acts by inhibiting calcium release from bone.
The Cauliflower<i>Or</i>Gene Encodes a DnaJ Cysteine-Rich Domain-Containing Protein That Mediates High Levels of β-Carotene Accumulation (2006)

Despite recent progress in our understanding of carotenogenesis in plants, the mechanisms that govern overall carotenoid accumulation remain largely unknown. The Orange (Or) gene mutation in cauliflower (Brassica oleracea var botrytis) confers the accumulation of high levels of beta-carotene in various tissues normally devoid of carotenoids. Using positional cloning, we isolated the gene representing Or and verified it by functional complementation in wild-type cauliflower. Or encodes a plastid-associated protein containing a DnaJ Cys-rich domain. The Or gene mutation is due to the insertion of a long terminal repeat retrotransposon in the Or allele. Or appears to be plant specific and is highly conserved among divergent plant species. Analyses of the gene, the gene product, and the cytological effects of the Or transgene suggest that the functional role of Or is associated with a cellular process that triggers the differentiation of proplastids or other noncolored plastids into chromoplasts for carotenoid accumulation. Moreover, we demonstrate that Or can be used as a novel genetic tool to induce carotenoid accumulation in a major staple food crop. We show here that controlling the formation of chromoplasts is an important mechanism by which carotenoid accumulation is regulated in plants.
Finite element analysis of mechanically amplified CMUTs (2013)

We introduce the possibility of improving a single-cell capacitive micromachined ultrasonic transducer (CMUT) for air-coupled ultrasound by simply adding a hollow conical-shaped structure (horn) on top of the CMUT plate. The main objective is to improve both transmit and receive sensitivity by lowering the center-to-average displacement ratio, which for bending plate operated devices inherently is limited. In addition, for receive mode the force generated from the impinging sound pressure wave is concentrated to the center of the plate, resulting in larger signals and, in contrast to piston-shaped plates, the horn has the advantage of only moderately increasing the modal mass of the structure. By using finite element analysis and first sound pressure measurements of our modified CMUT, we demonstrate that this idea is feasible and promising for air-coupled CMUTs operating at frequencies below 150 kHz, as it has been been proven to be successful for commercially available piezoelectric-driven bending plate devices as well.
Comparative In Vitro Efficacies and Antimicrobial Durabilities of Novel Antimicrobial Central Venous Catheters (2006)

We investigated the efficacies and durability of novel antimicrobial central venous catheters (CVCs) in preventing the adherence of microbial organisms to the surfaces of the CVCs. Novel antimicrobial CVCs investigated in this in vitro study were impregnated with antibiotics (minocycline and rifampin), with Oligon agent (silver, platinum, and carbon black), with approved antiseptics (chlorhexidine and silver sulfadiazine), or with a novel antiseptic agent, gendine, which contains gentian violet and chlorhexidine. When tested against methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa, gendine-coated CVC segments provided protection against bacterial adherence significantly more than all other types of tested CVCs (P < 0.05). Gendine-coated CVCs also provided better protection against Candida albicans and Candida parapsilosis than CVCs impregnated with antibiotics or with silver, platinum, and carbon (P < 0.02). After 28 days of being soaked in serum, the CVCs impregnated with chlorhexidine and silver sulfadiazine and the CVCs impregnated with silver, platinum, and carbon had lost antimicrobial activity against MRSA, P. aeruginosa, and C. parapsilosis, and the CVCs impregnated with minocycline and rifampin had lost activity against P. aeruginosa and C. parapsilosis. The CVCs impregnated with gendine maintained antimicrobial activities against MRSA, P. aeruginosa, and C. parapsilosis after 28 days of being soaked in serum. Central venous catheters impregnated with the novel investigational antiseptic gendine showed in vitro efficacy and provided protection against bacterial adherence more than other approved novel antimicrobial-coated CVCs.
ChemInform Abstract: Preparation and Alkylation of 1,5‐Dihydro‐3H‐1,2,4‐thiadiazolo(3,4‐b)quinazolin‐5‐one 2,2‐Dioxides. (1990)

Abstract The title compounds (III) and (V) are prepared by reaction of respective isatoic anhydrides (I) or (IV) with the compound (II).
Topological Insulator Laser (2018)

We demonstrate a nonmagnetic topological insulator laser exhibiting topologically-protected transport. The topological properties of the system give rise to single mode lasing, robustness against fabrication defects, and higher slope efficiencies compared to its trivial counterpart.
Specific depletion of the B-cell population induced by aberrant expression of human interferon regulatory factor 1 gene in transgenic mice. (1991)

Interferons (IFNs) are well known both as antiviral proteins and as potent regulators of cell growth and differentiation. In fact, IFNs inhibit growth of various normal and transformed cell types. Previously, a nuclear factor, IRF-1 (interferon regulatory factor 1), which binds to type I IFN and some IFN-inducible gene promoters, was identified and cloned. Since the IRF-1 gene is both virus and IFN inducible, an intriguing issue is raised as to whether the IRF-1 gene is functioning in IFN-mediated regulation of cell growth and differentiation. In this study, we generated transgenic mice carrying the human IRF-1 gene linked to the human immunoglobulin heavy-chain enhancer. In the transgenic mice, all the lymphoid tissues examined showed a dramatic reduction in the number of B lymphocytes (B cells). Preparation and analysis of bone marrow cells from the chimeric mice indicated that the bone marrow is the effective site for specific depletion of the B-cell population. In fact, transgenic bone marrow cells cocultured with a bone marrow-derived stromal cell line revealed an altered B-cell maturation pattern.
Lyn Is Essential for Fcγ Receptor III–Mediated Systemic Anaphylaxis but Not for the Arthus Reaction (2001)

The Src family kinase Lyn initiates intracellular signal transduction by associating with a variety of immune receptors such as antigen receptor on B cells and high-affinity Fc receptor (FcR) for immunoglobulin Ig(E) (FcepsilonRI) on mast cells. Involvement of Lyn in the IgE-mediated immediate-type hypersensitivity is well documented, but the physiological significance of Lyn in IgG-dependent, type III low-affinity FcR for IgG (FcgammaRIII)-mediated responses is largely unknown. In this study, we generated a double-mutant mouse strain deficient in both type II FcR for IgG (FcgammaRIIB) and Lyn to exclude any involvement of inhibitory signaling by FcgammaRIIB, which otherwise downregulates FcgammaRIII-mediated cellular responses. FcgammaRIIB-deficient but Lyn-sufficient mice served as controls. The Lyn deficiency attenuated IgG-mediated systemic anaphylaxis in vivo, and significantly reduced calcium mobilization and degranulation responses of bone marrow-derived mast cells (BMMCs) in vitro. However, we found that either interleukin 4 or tumor necrosis factor alpha release by BMMCs was comparable to that from Lyn-deficient and control mice, and the reverse-passive Arthus reaction was equally induced in both mutant mice, indicating that Lyn is not involved in the onset of the IgG-mediated, FcgammaRIII-dependent late phase responses of mast cells. These findings provide us with insight into distinct signaling mechanisms in mast cells underlying the development of diverse pathologies as well as a therapeutic potential for selective treatment of allergic disorders.
Temperature Corrections for Time Domain Reflectometry Parameters (2012)

The waveforms from time domain reflectometry (TDR) tests on soil depend on the temperature of the soil being tested. This study provides a discussion of, and the basis for, temperature corrections for the parameters measured in the TDR test for use in calculating water content and dry density of soil. This paper is a companion to one that provides the basis for an updated ASTM Standard, but does not cover temperature effects. A brief synopsis of the new methodology is provided herein to identify parameters that are sensitive to temperature of the soil being tested.
A Synthetic Receptor Selective for Citrate (1997)

Applied molecular recognition—strong and selective binding of citrate in highly competitive media such as water and orange juice is reported. Five steps are enough to synthesize receptor 1 that is complementary in charge and shape of citrate. Electrostatic interactions and a network of hydrogen bonds, preorganized by steric effects, are the design principles responsible for the binding of receptor and citrate [Eq. (a)].
Scalable QoS provision through buffer management (1998)

In recent years, a number of link scheduling algorithms have been proposed that greatly improve upon traditional FIFO scheduling in being able to assure rate and delay bounds for individual sessions. However, they cannot be easily deployed in a backbone environment with thousands of sessions, as their complexity increases with the number of sessions. In this paper, we propose and analyze an approach that uses a simple buffer management scheme to provide rate guarantees to individual flows (or to a set of flows) multiplexed into a common FIFO queue. We establish the buffer allocation requirements to achieve these rate guarantees and study the trade-off between the achievable link utilization and the buffer size required with the proposed scheme. The aspect of fair access to excess bandwidth is also addressed, and its mapping onto a buffer allocation rule is investigated. Numerical examples are provided that illustrate the performance of the proposed schemes. Finally, a scalable architecture for QoS provisioning is presented that integrates the proposed buffer management scheme with WFQ scheduling that uses a small number of queues.
Design of a Wearable Scissored-Pair Control Moment Gyroscope (SP-CMG) for Human Balance Assist (2014)

Our research examines the feasibility of usign a wearable scissored-pair control moment gyroscope (CMG) for human balance assist. The CMG is a momentum exchange device consisting of a fast spinning flywheel mounted on a gimbal. The gimbal motion changes the direction of the flywheel rotation axis, which generates a reactionless torque. A scissored-pair CMG has the additional advantage of isolating the output torque to a single axis, where off-axis torques are canceled out. A properly designed CMG device worn as a backpack can apply a torque in the sagittal plane of the human trunk. This can help in restoring postural balance and in fall mitigation. This paper describes the complete design process of a scissored-pair CMG device with constraints on size, mass and dynamic properties for human wearability. A prototype of this device is built, utilizing a novel dual-flywheel design; it weighs about 8kg and is able to generate over 20Nm of torque. A custom hardware is built specifically for verifying the torque output of the device. To our knowledge this is the only device that generates the range of reactionless torque given its weight and size.
Advantages of intraoperative medical hyperspectral imaging (MHSI) for the evaluation of the breast cancer resection bed for residual tumor (2005)

709 Background: Medical Hyperspectral Imaging (MHSI) is a novel, camera-based method of imaging spectroscopy that integrates spatial & spectroscopic data from tissue in a simple image. Despite advances in surgery, adequate breast tumor resection is an issue with over 30% recurring locally. MHSI may provide noninvasive, rapid, & inexpensive evaluation of residual cancer in the tumor bed at the time of resection. Here, we demonstrate proof-of-principle in a preclinical rat model. Methods: Female Sprague-Dawley rats received 50mg/kg DMBA by gastric gavage at age 8wks to induce breast tumors. 21 rats developed multiple tumors. We studied 98 tumors and performed partial resection of 41 tumors, yielding 41 full tumor/partial resection/tumor bed sets for analysis. Tumor was exposed & resected, intentionally leaving a small (0.5mm) piece of residual tumor in the bed. Gross examination, MHSI & histopathology were recorded. MHSI using visible light system (HyperMed, Inc., Watertown, MA) provided 40μm resolution (field of view 4X6cm). Algorithms based on spectral characteristics of tissue type were developed to distinguish tumor & normal tissues. Primary endpoint was designation of tumor/normal tissue found to remain in the tumor bed by gross exam, MHSI algorithm, & histology. Results: Interim analysis on 16 full sets of tumor bed data (gross/MHSI/hist.) showed that MHSI correctly identified tumor in all cases & detected tumor in the resection bed of 0.5mm whereas standard histopathology failed to do so in 2 cases (agreement kappa = 0.75). Conclusions: MHSI may provide reliable data in near-real time with a convenient device for the surgeon in the operating room. MHSI shows promise for increasing sensitivity of detection of residual tumor over current surgical tissue sampling techniques. Follow-on studies in patients are planned. Supported by: CDMRP Concept Award, DAMD17-03-1-0767 BC024521, NIH-NIEHS I-P01 ES11624–03 Author Disclosure Employment or Leadership Consultant or Advisory Role Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration HyperMed HyperMed HyperMed HyperMed
On Fiber Alignment Using Fluid-Dynamic Forces (1977)

A simple approach to the alignment of short fibers moving in an air stream was explored, in which transverse air jets acted to alter main stream velocity and direction in a desired manner. An approximate analysis was developed for the effects of aerodynamic forces on fiber motion and was combined with a theory for the influence of transverse air jets on the main flow. Experiments on fiber alignment using this approach were performed, the principal data being multiflash photographs of the fiber motion. The approximate theory is in qualitative agreement with the experimental results. These results showed that fiber alignment parallel to the main stream can be achieved for a wide range of initial fiber angles. Further, this alignment can be performed with low-speed air flows, which may facilitate fiber handling in many applications.
Coal liquefaction process. [coal pretreated with H/sub 2/S] (1978)

A coal liquefaction chargestock is first treated with a hydrogen sulfide-containing gas and thereafter subjected to coal liquefaction conditions. It has been found that pretreatment of the coal liquefaction feed with a hydrogen sulfide-containing gas gives improved coal liquefaction results such as coke suppression and an increase of liquid yield.