gebhart/patrepeval huggingface dataset:
Characterization of amorphous semiconducting silicon-boron alloys prepared by plasma decomposition (1979)

Amorphous semiconducting films of the Si-B binary system have been prepared by rf plasma decomposition of silane-diborane gas mixtures. The infrared vibrational modes, optical absorption, conductivity, spin resonance, and hydrogen content of these films have been studied as a function of preparation conditions. These alloy films differ substantially from chalcogenide glasses on the one hand and from group-IV amorphous semiconductors on the other. They contain between 10- and 45-at.% hydrogen and between ${10}^{18}$ and ${10}^{19}$ ${\mathrm{cm}}^{\ensuremath{-}3}$ unpaired spins. The spin-resonance linewidth is inhomogeneously broadened because of a large spectrum of bond distances and bond strengths. This spectrum yields a few very broad infrared absorption bands and, in the boron-rich films, an unusually broad and slowly varying absorption edge. This large spectrum of bond strengths results from the electron-deficient nature of boron which can associate with the environment in two-center and three-center bonds involving hydrogen, silicon, and other boron atoms. The slope of the conductivity curves decreases slowly without distinct exponential regions and without showing Mott's law of variable-range hopping near 77 K. Except for the two end compositions of the binary system, the Fermi level is close to the valence band, presumably because tetrahedrally coordinated boron atoms act as acceptors and produce a self-doping effect.
Dispersion-insensitive measurement of thickness and group refractive index by low-coherence interferometry (2000)

We describe a low-coherence interferometric technique for simultaneous measurement of geometric thickness and group refractive index of highly dispersive samples. The technique is immune to the dispersion-induced asymmetry of the interferograms, thus overcoming limitations associated with some other low-coherence approaches to this simultaneous measurement. We use the experimental configuration of a tandem interferometer, with the samples to be characterized placed in an air gap in one arm of the measurement interferometer. Unambiguous, dispersion-insensitive measurements of critical group-delay imbalances in the measurement interferometer are determined from the optical frequency dependence of interferogram phases, by means of dispersive Fourier transform spectrometry. Sample thickness and group refractive index are calculated from these group delays. A thickness measurement precision of 0.2 microm and group index measurement accuracy of 5 parts in 10(5) across a wavelength range of 150 nm have been achieved for BK7 and fused-silica glass samples in the thickness range 2000 to 6000 microm.
Determination of Uranyl Incorporation into Biogenic Manganese Oxides Using X-ray Absorption Spectroscopy and Scattering (2005)

Biogenic manganese oxides are common and an important source of reactive mineral surfaces in the environment that may be potentially enhanced in bioremediation cases to improve natural attenuation. Experiments were performed in which the uranyl ion, UO2(2+) (U(VI)), at various concentrations was present during manganese oxide biogenesis. At all concentrations, there was strong uptake of U onto the oxides. Synchrotron-based extended X-ray absorption fine structure (EXAFS) spectroscopy and X-ray diffraction (XRD) studies were carried out to determine the molecular-scale mechanism by which uranyl is incorporated into the oxide and how this incorporation affects the resulting manganese oxide structure and mineralogy. The EXAFS experiments show that at low concentrations (<0.3 mol % U, <1 microM U(VI) in solution), U(VI) is present as a strong bidentate surface complex. At high concentrations (>2 mol % U, >4 microM U(VI) in solution), the presence of U(VI) affects the stability and structure of the Mn oxide to form poorly ordered Mn oxide tunnel structures, similar to todorokite. EXAFS modeling shows that uranyl is present in these oxides predominantly in the tunnels of the Mn oxide structure in a tridentate complex. Observations by XRD corroborate these results. Structural incorporation may lead to more stable U(VI) sequestration that may be suitable for remediation uses. These observations, combined with the very high uptake capacity of the Mn oxides, imply that Mn-oxidizing bacteria may significantly influence dissolved U(VI) concentrations in impacted waters via sorption and incorporation into Mn oxide biominerals.
Highly Enantioselective Reactions of Configurationally Labile α-Thioorganolithiums Using Chiral Bis(oxazoline)s via Two Different Enantiodetermining Steps (2000)

A cumene solution of α-stannyl benzyl phenyl sulfide was treated with n-BuLi and bis(oxazoline)-iPr at −78 °C and subsequently with benzophenone to give the product with 99% ee. We confirmed that the reaction of α-lithio benzyl phenyl sulfide proceeds through a dynamic kinetic resolution pathway. The enantioselective reactions of α-lithio benzyl 2-pyridyl sulfide gave the products with stereochemistry reverse to that obtained in the reaction of benzyl phenyl sulfide. We confirmed that this reaction proceeds through a dynamic thermodynamic resolution pathway in which the reaction with an electrophile proceeds faster than interconversion between the diastereomeric complexes.
Ferroelectric Liquid Crystals with High Spontaneous Polarization (2011)

The influence of chemical structure on spontaneous polarization, Ps, of a ferroelectric chiral smectic C meso¬phase is discussed. It is shown that the asymmetry, the presence of polar groups in the chiral centre, substitution, the presence of heterocycles in the central skeleton of the molecule and the hindrance of intramolecular rotations are the most important factors for the magnitude of the Ps. A survey of more than 60 compounds is presented including those with spontaneous polarization above 400 nC cm−2.
Absolute frequency calibration of the CO<sub>2</sub> isotope laser transitions (1976)

The frequencies of rare CO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> isotope lasers are measured by comparison with <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">12</sup> C <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">16</sup> O <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> reference lines and with each other. Improved heterodyne techniques are used to generate difference frequencies in a liquid-nitrogen-cooled HgCdTe varactor photodiode. Microwave frequency counter measurements of the difference frequencies are then used to calculate the band centers, rotational constants and transition frequencies with an estimated accuracy of less than a few kilohertz. Selected applications of CO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> isotope lasers in precision heterodyne calibration, spectroscopy, microwave and IR synthesis are described.
ChemInform Abstract: 2,2′‐BIPYRIDINE N‐OXIDE CHELATES WITH DIVALENT 3D METAL PERCHLORATES (1973)

Abstract Hydratisierte Metallperchlorate reagieren in Äthanol in Gegenwart von Triäthyl‐ orthoformiat mit Bipyridyl‐N‐oxid zu den Chelatkomplexen (Ia) bzw. (Ib), die durch IR‐ und elektronenspektroskopische Daten sowie magnetische und Leitfähigkeitsmessungen charakterisiert wurden.
Metabolic changes in alveolar type II cells after exposure to hydrogen peroxide (1990)

Since oxygen metabolites may play an important role in pulmonary oxidant injury, the effects of hydrogen peroxide (H2O2) on energy metabolism in alveolar type II cells isolated from rats were studied. The major effect of H2O2 is a rapid and dramatic reduction in the steady-state level of cellular ATP; e.g., ATP levels are reduced by 77 +/- 3% after only 5 min of exposure to H2O2 (0.5 mM). Cellular oxygen consumption is affected in a similar manner, suggesting that ATP synthesis is impaired. Experiments with isolated lung mitochondria demonstrate that exposure to 0.5 mM H2O2 for 5 min inhibits the rate of mitochondrial ATP synthesis by 51 +/- 3%. The site of mitochondrial ATP synthesis inhibition by H2O2 appears to be the adenosinetriphosphatase-synthase enzyme complex which phosphorylates ADP to ATP. Mitochondrial electron transport is unaffected. The association of 3-O-methylglucose with type II cells and glycolytic metabolism, measured as lactate production, are reduced by 25-35% by H2O2. The data also show that the cells are capable of recovery following exposure to H2O2, at least at lower exposure levels. These results indicate that exposure of type II cells to H2O2 alters the energy state of the cells by decreasing ATP synthesis. In turn, other important cellular functions may be impaired.
The Alzheimer's Disease Assessment Scale: Evaluation of Psychometric Properties and Patterns of Cognitive Decline in Multicenter Clinical Trials of Mild to Moderate Alzheimer's Disease (2001)

There is a relationship between baseline severity and magnitude of cognitive decline. In 6-month trials, measurement error makes a substantial contribution to the variance in ADAS-Cog change scores. Sensitivity to intervention effects will therefore depend both on the variability and magnitude of change. Such data must be considered when designing future trials to minimize measurement error variability and increase sensitivity for specific populations.
A Pipeline Fast Fourier Transform (1970)

This paper describes a novel structure for a hardwired fast Fourier transform (FFT) signal processor that promises to permit digital spectrum analysis to achieve throughput rates consistent with extremely wide-band radars. The technique is based on the use of serial storage for data and intermediate results and multiple arithmetic units each of which carries out a sparse Fourier transform. Details of the system are described for data sample sizes that are binary multiples, but the technique is applicable to any composite number.
Analytical method for determination of disaccharides derived from keratan sulfates in human serum and plasma by high‐performance liquid chromatography/turbo‐ionspray ionization tandem mass spectrometry (2007)

We established a highly sensitive LC/MS/MS method for the analysis of the disaccharides produced from keratan sulfates (KS). It was revealed that the disaccharides produced by keratanase II enzymatic digestion of KS could be determined with high sensitivity by negative ion mode of multiple reaction monitoring. Furthermore, monosulfated and disulfated disaccharides can be separated using a Hypercarb (2.0 mm i.d. x 150 mm, 5 microm) with a gradient elution of acetonitrile-0.01 m ammonium bicarbonate (pH 10). This method was applied to the determination of KS in serum and plasma of control subjects. The intra-day precision expressed as %CV was within 6.8% for five replicate analyses with three different control serum. The inter-day (overall, n = 15) precision was within 7.3% for three days. This method is sensitive, reproducible and would be useful for clinical analysis.
Exploring the Trypanosoma brucei Hsp83 Potential as a Target for Structure Guided Drug Design (2013)

Human African trypanosomiasis is a neglected parasitic disease that is fatal if untreated. The current drugs available to eliminate the causative agent Trypanosoma brucei have multiple liabilities, including toxicity, increasing problems due to treatment failure and limited efficacy. There are two approaches to discover novel antimicrobial drugs--whole-cell screening and target-based discovery. In the latter case, there is a need to identify and validate novel drug targets in Trypanosoma parasites. The heat shock proteins (Hsp), while best known as cancer targets with a number of drug candidates in clinical development, are a family of emerging targets for infectious diseases. In this paper, we report the exploration of T. brucei Hsp83--a homolog of human Hsp90--as a drug target using multiple biophysical and biochemical techniques. Our approach included the characterization of the chemical sensitivity of the parasitic chaperone against a library of known Hsp90 inhibitors by means of differential scanning fluorimetry (DSF). Several compounds identified by this screening procedure were further studied using isothermal titration calorimetry (ITC) and X-ray crystallography, as well as tested in parasite growth inhibitions assays. These experiments led us to the identification of a benzamide derivative compound capable of interacting with TbHsp83 more strongly than with its human homologs and structural rationalization of this selectivity. The results highlight the opportunities created by subtle structural differences to develop new series of compounds to selectively target the Trypanosoma brucei chaperone and effectively kill the sleeping sickness parasite.
Eosinophil Adhesion and Maturation is Modulated by Laminin (1993)

Eosinophils (Eo) participate in the inflammatory response to parasites, allergins, toxins, and epitopes recognized by autoimmune antibodies. Nonetheless, little attention has heretofore been paid to the interactions of Eo with extracellular matrix (ECM) proteins during their migration through the subendothelial basement membrane and into the surrounding tissue. Therefore, we have studied the adhesion of Eo to specific ECM proteins and the effect of this adhesion on Eo viability and maturation. Control Eo (from normal donors) adhere no better to substrates coated with laminin (LM), fibronectin (FN), cytotactin (CT), or collagen types I or IV (Col IV) than they do to human serum albumin coated substrates. In contrast, Eo activated in vitro with IL-5 or in vivo in patients with eosinophilia bind well to LM, FN and Col IV. LM is by far the most avid ligand among these molecules. For example, 43% of input cells bind to a substrate bearing 200 fmol/cm2 of LM; a similar level of adhesion to FN requires 30 times as much absorbed protein. Antibody inhibition experiments suggest that the alpha 6 beta 1 integrin heterodimer is the predominant LM receptor on these cells. Flow cytometry showed similar levels of these subunits on control and activated Eo, suggesting that Eo adhesion to LM is not regulated simply by cell surface integrin concentration. The effects of ECM proteins on Eo behavior were also examined. A LM-coated substrate (with no added cytokine) was found to be almost as effective as IL-5 in maintaining Eo viability while an equally adhesive FN-coated substrate had much less effect. Normally, even in the presence of 10% serum, no Eo survive a 5-day incubation in vitro unless IL-3, IL-5, or GM-CSF is added to the medium. Conditions that inhibit adhesion to LM (anti-integrin antibodies in the medium or CT on the substrate) and certain anti-cytokine antibodies inhibited the promotion of Eo viability by LM. During incubation on LM, Eo become hypodense, as they do in the presence of IL-5, indicating that they have become activated. These observations suggest that the interactions of Eo and ECM proteins may be important both for their potential to direct Eo migration and for their ability to regulate Eo viability, cytokine production, and maturation.
Assembly of synthetic cellulose I. (1994)

Cellulose microfibrils with an electron diffraction pattern characteristic of crystalline native cellulose I have been assembled abiotically by means of a cellulase-catalyzed polymerization of beta-cellobiosyl fluoride substrate monomer in acetonitrile/acetate buffer. Substantial purification of the Trichoderma viride cellulase enzyme was found to be essential for the formation of the synthetic cellulose I allomorph. Assembly of synthetic cellulose I appears to be a result of a micellar aggregation of the partially purified enzyme and the substrate in an organic/aqueous solvent system favoring the alignment of glucan chains with the same polarity and extended chain conformation, resulting in crystallization to form the metastable cellulose I allomorph.
Role of antioxidants in the treatment of burn lesions. (2008)

Burns are a major health problem worldwide, with high mortality and morbidity in addition to causing changes in the quality of life of burn patients. Utilizing antioxidant therapeutic strategies depending on new mechanisms involved in the pathogenesis of burns-related "oxidative stress" may be considered a promising step in burns management. This study involved 180 burn patients of varying age and either sex and with varying burns percentages. The patients were subdivided into six groups (A, B, C, D, E, and F); each group thus included 30 patients. Patients in groups B, C, D, E, and F were treated with antioxidants (vitamin E with vitamin C, zinc sulphate, allopurinol, melatonin, and N-acetylcysteine respectively) while group A was treated according to hospital policy, without any antioxidant; also, healthy subjects (group G) were involved in the study as a control group for comparison.In each group we examined serum malondialdehyde and serum glutathione levels, serum zinc and copper levels, liver function, renal function, mortality rate, and healing time, using standard methods. It was found that the administration of antioxidants to burn patients produced significant improvement in the parameters studied compared with group A (no antioxidant given). This study clearly shows the importance of the therapeutic targeting of oxidative stress in the treatment of burns. It is important to consider antioxidant a most effective weapon that must be added to the arsenal available in the combating of burn complications.
British Association for the Study of Community Dentistry (BASCD) guidance on sampling for surveys of child dental health. A BASCD coordinated dental epidemiology programme quality standard. (1997)

The British Association for the Study of Community Dentistry (BASCD) is responsible for the coordination of locally based surveys of child dental health which permit local and national comparisons between health authorities and regions. These surveys began in 1985/86 in England and Wales, 1987/88 in Scotland and 1993/94 in Northern Ireland. BASCD has taken an increasing lead in setting quality standards in discussion with the NHS Epidemiology Coordinators of the Dental Epidemiology Programme. This paper comprises guidance on the sampling for these surveys.
Gene encoding zonula occludens toxin (zot) does not occur independently from cholera enterotoxin genes (ctx) in Vibrio cholerae (1993)

Of 167 Vibrio cholerae isolates screened for sequences homologous with zonula occludens toxin (zot) or cholera toxin (ctx) genes, 3.0% of non-O1, 100.0% of clinical O1, and 0.0% of environmental O1 strains contained both zot and ctx. zot was present only in strains that were ctx positive; all ctx-positive strains carried zot. The absence of zot-positive, ctx-negative strains suggests ZOT is not an independent virulence factor for V. cholerae, although ZOT may play a role in the pathogenesis of toxigenic strains.
Design procedure for optimum or rotationally invariant trellis codes (1990)

The authors present examples for a search-free, step-by-step design procedure for trellis coded modulation that involves both linear and nonlinear convolutional encoders. Such a procedure starts with a derivation of a trellis description of the code and ends with the series combination of a convolutional encoder and a natural bit mapper to modulation symbols to generate the code. The derivation of this structure is obtained from the analytic description of the code, which also could be used as the modulated signal generator. The examples presented include an eight-dimensional PSK (phase-shift keying) code and a nonlinear, rotationally invariant code.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
BSLD threshold driven power management policy for HPC centers (2010)

In this paper, we propose a power-aware parallel job scheduler assuming DVFS enabled clusters. A CPU frequency assignment algorithm is integrated into the well established EASY backfilling job scheduling policy. Running a job at lower frequency results in a reduction in power dissipation and accordingly in energy consumption. However, lower frequencies introduce a penalty in performance. Our frequency assignment algorithm has two adjustable parameters in order to enable fine grain energy-performance trade-off control. Furthermore, we have done an analysis of HPC system dimension. This paper investigates whether having more DVFS enabled processors for same load can lead to better energy efficiency and performance. Five workload traces from systems in production use with up to 9 216 processors are simulated to evaluate the proposed algorithm and the dimensioning problem. Our approach decreases CPU energy by 7%- 18% on average depending on allowed job performance penalty. Using the power-aware job scheduling for 20% larger system, CPU energy needed to execute same load can be decreased by almost 30% while having same or better job performance.
Action potential propagation in transverse-axial tubular system is impaired in heart failure (2012)

The plasma membrane of cardiac myocytes presents complex invaginations known as the transverse-axial tubular system (TATS). Despite TATS's crucial role in excitation-contraction coupling and morphological alterations found in pathological settings, TATS's electrical activity has never been directly investigated in remodeled tubular networks. Here we develop an ultrafast random access multiphoton microscope that, in combination with a customly synthesized voltage-sensitive dye, is used to simultaneously measure action potentials (APs) at multiple sites within the sarcolemma with submillisecond temporal and submicrometer spatial resolution in real time. We find that the tight electrical coupling between different sarcolemmal domains is guaranteed only within an intact tubular system. In fact, acute detachment by osmotic shock of most tubules from the surface sarcolemma prevents AP propagation not only in the disconnected tubules, but also in some of the tubules that remain connected with the surface. This indicates that a structural disorganization of the tubular system worsens the electrical coupling between the TATS and the surface. The pathological implications of this finding are investigated in failing hearts. We find that AP propagation into the pathologically remodeled TATS frequently fails and may be followed by local spontaneous electrical activity. Our findings provide insight on the relationship between abnormal TATS and asynchronous calcium release, a major determinant of cardiac contractile dysfunction and arrhythmias.
Multi-processor programming in the embedded system curriculum (2009)

Teaching embedded system design is challenging, as the subject covers a wide range of aspects, and also involves skills that students do not learn from a text book. As a result, hands-on projects, with varying degree of complexity, are the most common approach in existing courses. Traditionally, the projects are limited to uni-processor systems, and do not address the complications involved in parallelising applications and mapping them to multi-processor systems. In this paper, we describe a two-year-old embedded systems design course given at Eindhoven University of Technology. In the course, groups of four students are faced with the problem of putting an embedded JPEG decoder on the market within one semester. The starting point is a decoder written in sequential C and an embedded multiprocessor system, running on an FPGA. We describe the ideas and organisation of the course, and give examples of what challenges the students, as well as the instructors, are faced with. We exemplify results and give suggestions to those wishing to teach embedded multi-processor programming elsewhere.