cssi/SciSciGPT-SciSciNet huggingface dataset:
Formation and identification of 3-keto-5-aminohexanoic acid, a probable intermediate in lysine fermentation.

Abstract A neutral, heat-labile compound (II) has been detected as a product of lysine fermentation by cell-free extracts of Clostridium SB4. A 2 to 5% yield of II from lysine is observed when coenzyme A is omitted from an otherwise complete reaction mixture. 3,5-Diaminohexanoate appears to be the immediate precursor of Compound II since it can be converted to II under conditions not permitting the utilization of lysine or β-lysine. Under favorable conditions, 3,5-diaminohexanoate is enzymically converted to Compound II in 20 to 30% yield. The cofactors required for the reaction are NAD and α-ketoglutarate or pyruvate; the latter is active only when lactic dehydrogenase is also added. The formation of Compound II appears to occur by a reversible NAD-dependent oxidative deamination of 3,5-diaminohexanoate. The keto acids function as oxidants in the reoxidation of NADH by the appropriate dehydrogenases. Although Compound II has not been isolated as a pure compound because of its instability, chemical and enzymic studies indicate that its structure is 3-keto-5-aminohexanoate. Compound II is reduced by borohydride to a heat-stable hydroxyamino acid, and is decarboxylated to a basic methyl ketone. The latter reacts with hypoiodite to give iodoform and β-aminobutyrate; therefore, it appears to be 2-keto-4-aminopentane.
Morphological Image Processing

This chapter contains sections titled: Introduction Fundamental Concepts and Operations Dilation and Erosion Compound Operations Morphological Filtering Basic Morphological Algorithms Grayscale Morphology Tutorial 13.1: Binary Morphological Image Processing Tutorial 13.2: Basic Morphological Algorithms Problems
Abbreviated oral history interview training: tutorial presentation

This workshop is designed as a first step in training interviewers for the Women Computing Educators Oral History Project. This workshop will provide background, techniques, guidelines, equipment selection criteria, and demonstrations of conducting interviews. Those completing the workshop will understand the project's goals and be positioned to undertake further training to become project contributors as interviewers and consultants. The goal of the project is to create a significant collection of narratives of women computing educators, serve as a mechanism for preserving the history of the female pioneers in computing education and provide role models to attract young women to computing.
Infiltration Equations Modified for Surface Effects

A series of equations were developed for predicting infiltration into soils with modified surfaces. The Green-Ampt approach was used in their development. They have the same functional form as the Green-Ampt and Mein-Larson two-stage infiltration equations to which they reduce for the case of a uniform soil profile. The equations were applied to coarse over-fine and fine over-coarse soil stratifications and showed good agreement with both observed infiltration rates and infiltration rates predicted by numerical solution of Richards' equation. The equations were also applied to an Ida silt loam soil to illustrate the magnitude of the predicted effect of surface sealing on infiltration. Analysis was performed for two different initial moisture contents, three different rainfall intensity ratios, and four different conductivity ratios.
Superconductivity and spin fluctuations in the electron-doped infinitely-layered high Tc superconductor Sr0.9La0.1CuO2 (Tc=42 K)

Abstract We report 63Cu NMR studies on uniaxially aligned and unaligned powder samples of an electron-doped infinitely-layered high Tc cuprate superconductor Sr0.9La0.1CuO2 (Tc = 42 K). We measured the nuclear spin-lattice relaxation rate 1 T 1 up to 800 K. We found from the temperature dependence of 1 T 1 T that the wave-vector-averaged spin susceptibility is highly enhanced by spin-fluctuations in the normal state, resulting in a Curie-Weiss behavior. Below Tc, we did not observe a Hebel-Slichter coherence peak of 1 T 1 , suggesting an unconventional nature of the symmetry of the superconducting order parameter. These results are quite similar to those observed for some hole-doped high Tc cuprates.
Executing multithreaded programs efficiently

This thesis presents the theory, design, and implementation of Cilk (pronounced "silk") and Cilk-NOW. Cilk is a C-based language and portable runtime system for programming and executing multithreaded parallel programs. Cilk-NOW is an implementation of the Cilk runtime system that transparently manages resources for parallel programs running on a network of workstations. Cilk is built around a provably efficient algorithm for scheduling the execution of strict multithreaded computations. Based on the technique of work stealing, this algorithm achieves time, space, and communication bounds that are all within a small constant factor of optimal. Using these performance guarantees, Cilk provides a simple abstraction of performance that allows programmers to accurately predict how program changes will affect execution time. Cilk-NOW provides high-level resource management services so that Cilk programs can efficiently run on a network of workstations. These services include adaptive parallelism and fault tolerance. With adaptive parallelism, programs execute on a pool of workstations that dynamically grows and shrinks in response to both the availability of "idle" machines and the availability of parallelism within the program. Cilk-NOW also provides transparent fault tolerance with a fully distributed checkpointing mechanism. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)
Can science be at the centre of modern culture

Increasingly, such concepts as the `End of the Modern Era', the `End of Progress', and the `End of Objectivity' have been given public exposure, originating from parts of academe and from populariz...
The isolation and chemistry of tantalum dimethylamides containing resolved 3,3′-disubstituted-1,1′-bi-2,2′-naphthoxide ligands

Reaction of the tantalum dimethylamide substrates [Ta(NMe2)5] or mer,cis-[Ta(NMe2)2Cl3(HNMe2)] with one equivalent of the 3,3′-disubstituted-2,2′-dihydroxy-1,1′-binaphthyl [H2O2C20H10(R)2-3,3′] (R = SiMe3, 1; SiMe2Ph, 2; SiMePh2, 3; SiPh3, 4) leads to the series of amine adducts [Ta(O2C20H10R2-3,3′)(NHMe2)(NMe2)3] (R = SiMe3, 5; SiMe2Ph, 6; SiMePh2, 7; SiPh3, 8) and [Ta(O2C20H10R2-3,3′)(NHMe2)(NMe2)Cl2] (R = SiMe3, 9; SiMe2Ph, 10; SiMePh2, 11; SiPh3, 12). Structural analyses by X-ray diffraction of (S)-5, (R)-7 and (R,S)-8 show a pseudo-octahedral geometry about tantalum with the coordinated dimethylamine ligand located cis to the two naphthoxide oxygen atoms. In the case of (S)-9, (R)-10 and (S)-12, the solid-state structure consists of both chloride ligands being located trans to the two naphthoxide oxygen atoms. Solution NMR spectroscopic properties of 5–12 are consistent with an identical structure being adopted in solution with the amine ligands being strongly bound in all cases. When (S)-5 is heated under vacuum the dimethylamine ligand is lost leading to [Ta(O2C20H10{SiMe3}2-3,3′)(NMe2)3] (S)-13. Reaction of (S)-5 with SiCl4 leads to a mixture of [Ta(O2C20H10{SiMe3}2-3,3′)(NHMe2)Cl3] (S)-14 and [Ta(O2C20H10-{SiMe3}2-3,3′)Cl4][Me2NH2] (S)-15. The solid-state structure of (S)-15 was determined. The amine/amide ligands in (S)-12 undergo insertion of CS2 leading to the dimethyldithiocarbamate, (S)-[Ta(O2C20H10-3,3′-{SiPh3}2)(CS2NMe2)2Cl] (S)-16. The solid state structure of (S)-16 consists of a pentagonal bipyramidal geometry about Ta with an axial oxygen and chloride ligand.
Temperature-Dependent Hypersonic Flow Patterns of Expanding High-Density Metal Vapor Plasma from Capillary Source Simulating Plasma Flow Following a Fusion Disruption

Capillary discharge devices generating electrothermal plasmas from ablation of a liner material exposed to high heat flux are adequate devices to simulate fusion disruptions. Expansion of capillary-generated plasma into large volume simulates the evolution of the aerosol and plasma particulates into the reactor vacuum vessel. Effect of non-linearity and plasma bulk temperature on the adiabatic compressibility index was previously investigated showing considerable effect on the bulk flow parameters of polycarbonate plasma formed by the ablation of the capillary inner wall. In a fusion reactor, metals in the plasma-facing components such as the divertor, limiter, and first wall, will experience evaporation and formation of metal-vapor plasmas. Mathematical models have been developed to investigate the adiabatic compressibility index of ionized bulk metal vapors taking into account atomic and cluster ionization of metals, in addition to the effect of plasma bulk temperature and other nonlinearities. An important aspect of this current work is the distinction of the ionized states of metallic species instead of temperature-dependent lumped effective atomic number.
Electronic structure and the origin of the high ordering temperature in SrRu 2 O 6

SrRu2O6 is a layered honeycomb-lattice material with an extraordinarily high magnetic ordering temperature. We investigated this material using density functional calculations. We find that the energy scales for moment formation and ordering are similar and high. Additionally, we find that the magnetic anisotropy is high and favors moments oriented along the c axis. This provides an explanation for the exceptionally high ordering temperature. Finally, the compound is found to be semiconducting at the bare density functional level, even without magnetic order. Lastly, we discuss experimental consequences of this scenario for the high ordering temperature.
Effect of the inspiratory flow pattern on inspiration/expiration transition of lung vibrations in mechanically ventilated patients

Mechanical ventilation can be performed using different inspiratory flow patterns. We used vibration response imaging (VRI) technology to ascertain the intensity of lung vibration with different inspiratory flow patterns during various modes of mechanical ventilation.
Mixed-valence ferrocene systems temperature dependence in the mössbauer spectra of [Fe(II)Fe(III) [1.1] ferrocenophanes

Abstract 57Fe Mossbauer spectra (300 and 4.2°K) have been determined for dioxidized [Fe(III)Fe(III)] biferrocenylene; a large quadrupole splitting (2.89 mm/sec at 300°K) was interpreted in terms of extensive delocalization of e2g electrons resultant from an FeFe bonding interaction. Mossbauer and electronic absorption spectra have also been determined for two mono-oxidized [1.1] ferrocenophanes. Temperature dependence is noted in the [Fe(II)Fe(III)] ferrocenophane Mossbauer spectra and is tentatively associated with a phase transition wherein the FeFe distance is changed to permit greater FeFe exchange interaction.
Carboxylic acid adsorption on NiO(100) characterized by X-ray photoelectron and high resolution electron energy loss spectroscopies

Formic, acetic and propionic acids have been adsorbed onto NiO(100) at 300 K and the resulting species characterized by X-ray photoelectron spectroscopy (XPS) and high resolution electron energy loss spectroscopy (HREELS). As do many ionic solids, nickel oxide possesses a strong series of Fuchs-Kliewer multiple phonon losses, which obscures the weaker adsorbate vibrational structure. A novel phonon deconvolution procedure that removes multiple phonons has, therefore, been used in analyzing the HREELS data. NiO(100) exhibits amphoteric chemisorptive properties, dissociatively adsorbing the acids as carboxylates and surface hydroxyls. Adsorption saturates after approximately 10000 langmuir to yield one carboxylate for every two nickel sites. By stoichiometry, one half of all surface oxygen sites are assumed to be hydroxylated. A tilted carboxylate geometry is evident in the high value of thev s(COO) vibrational mode observed in the HREEL spectra.
Source function approach for radiative heat transfer analysis

A source function approach for analysis of 3D radiative heat transfer in absorbing, emitting, and anisotropically scattering media is developed. Two integral equations relating the source function for the gas an leaving intensity for surfaces are developed incorporating direct exchange factors between differential elements. The resulting equations are then discretized using a numerical scheme. Numerical results based on the present approach are presented for a 3D idealized furnace model. The results are in excellent agreement with the existing solutions. 10 refs.
Effects of Heat Stress on Reproduction

Abstract When dairy cattle are subjected to heat stress, reproductive efficiency declines. Cows under heat stress have reduced duration and intensity of estrus, altered follicular development, and impaired embryonic development. However, the extent of reduction in reproductive efficiency during summer in the United States or elsewhere is difficult to assess unless reproductive measures are calculated monthly based on results of actual inseminations rather than as rolling annual averages. Common methods to ameliorate effects of heat stress have been to provide cooling in the form of shades, soakers, fans, or evaporative coolers. Because negative effects of heat stress have been identified from 42 d before to 40 d after insemination, continual cooling must be provided. Tools for synchronization of estrus have been developed that greatly reduce the need for detection of estrus. Pregnancy rates were more consistent over season when timed artificial insemination programs were used compared with artificial insemination after detected estrus, although negative impacts of heat stress were still observed. Recently, calving in summer has been reported to reduce the success of a timed first insemination between 60 and 66 d postpartum, although some researchers have found calving in the summer to have a positive impact on days open. Other techniques that have been investigated to reduce the negative impact of heat stress on reproduction include embryo transfer, induction of accessory corpus lutea, and crossbreeding. Each technique has potential advantages but not without limitations or costs. Comparative economic evaluations of various combinations of strategies to attenuate negative effects of heat stress on both milk production and reproduction are needed.
2,3,7,8-Tetrachlorodibenzo-p-dioxin increases reactive oxygen species production in human endothelial cells via induction of cytochrome P4501A1

Studies in our laboratory have demonstrated that subchronic 2,3,7,8,-tetrachlorodibenzo-p-dioxin (TCDD) exposure of adult mice results in hypertension, cardiac hypertrophy, and reduced nitric oxide (NO)-mediated vasodilation. Moreover, increased superoxide anion production was observed in cardiovascular organs of TCDD-exposed mice and this increase contributed to the reduced NO-mediated vasodilation. Since cytochrome P4501A1 (CYP1A1) can contribute to some TCDD-induced toxicity, we tested the hypothesis that TCDD increases reactive oxygen species (ROS) in endothelial cells by the induction of CYP1A1. A concentration-response to 24h TCDD exposure (10pM-10nM) was performed in confluent primary human aortic endothelial cells (HAECs). Oxidant-sensitive fluorescent probes dihydroethidium (DHE) and 2',7'-dichlorofluorescin diacetate (DCFH-DA), were used to measure superoxide anion, and hydrogen peroxide and hydroxyl radical, respectively. NO was also measured using the fluorescent probe diaminofluorescein-2 diacetate (DAF-2DA). These assessments were conducted in HAECs transfected with siRNA targeting the aryl hydrocarbon receptor (AhR), CYP1A1, or CYP1B1. TCDD concentration-dependently increased CYP1A1 and CYP1B1 mRNA, protein, and enzyme activity. Moreover, 1nM TCDD maximally increased DHE (Cont=1.0+/-0.3; TCDD=5.1+/-1.0; p=0.002) and DCFH-DA (Cont=1.0+/-0.2; TCDD=4.1+/-0.5; p=0.002) fluorescence and maximally decreased DAF-2DA fluorescence (Cont=1.0+/-0.4; TCDD=0.68+/-0.1). siRNA targeting AhR and CYP1A1 significantly decreased TCDD-induced DHE (siAhR: Cont=1.0+/-0.1; TCDD=1.3+/-0.2; p=0.093) (siCYP1A1: Cont=1.0+/-0.1; TCDD=1.1+/-0.1; p=0.454) and DCFH-DA (siAhR: Cont=1.0+/-0.2; TCDD=1.3+/-0.3; p=0.370) (siCYP1A1: Cont=1.0+/-0.1; TCDD=1.3+/-0.2; p=0.114) fluorescence and increased DAF-2DA fluorescence (siAhR: Cont=1.00+/-0.03; TCDD=0.97+/-0.03; p=0.481) (siCYP1A1: Cont=1.00+/-0.03; TCDD=0.92+/-0.03; p=0.034), while siRNA targeting CYP1B1 did not. These data suggest that TCDD-induced increase in ROS is AhR-dependent and may be mediated, in part, by CYP1A1 induction.
Extracting information from counterfactual clauses

This study examined how people access the information in a complex grammatical construction like counterfactual clauses, for example, If Mary would have left, Judy would have died. The main issue was whether people would represent this information in a form that reflects its syntactic complexity, for example (false (Mary left)), or whether subjects would simplify the representation, for example (Mary stayed). The results of a timed verification task indicated that people do represent and extract information from the more complex representation. However, when given sufficient time, subjects simplify the complex representation and thereby reduce the number of operations necessary to subsequently verify the information or store it in long-term memory. Furthermore, a second experiment showed that after simplifying the information, subjects can remember performing the simplification and so can reconstruct the original surface structure.
Modified Modal Domain Analysis of a Bladed Rotor Using Coordinate Measurement Machine Data on Geometric Mistuning

Modified Modal Domain Analysis (MMDA), a reduced order modeling technique, is applied to a geometrically mistuned integrally bladed rotor to obtain its natural frequencies, mode shapes and forced response. The geometric mistuning of blades is described in terms of proper orthogonal decomposition (POD) of the coordinate measurement machine (CMM) data. Results from MMDA are compared to those from the full (360 degrees) rotor ANSYS model. It is found that the MMDA can accurately predict natural frequencies, mode shapes, and forced response. The effects of the number of POD features and the number of tuned modes used as bases for model reduction are examined. Results from frequency mistuning approaches, fundamental mistuning model (FMM) and subset of nominal modes (SNM), are also generated and compared to those from full (360 degree) rotor ANSYS model. It is clearly seen that FMM and SNM are unable to yield accurate results whereas MMDA yields highly accurate results.Copyright © 2013 by ASME
Propagation of a segment of bacteriophage λ-DNA in monkey cells after covalent linkage to a defective simian virus 40 genome

Abstract A 520 base pair DNA segment was excised from the bacteriophage λ-genome by cleavage with the bacterial restriction endonuclease, endo R. Hin dIII. This segment was covalently joined in vitro to an 880 base pair simian virus 40 (SV40) DNA segment which contains the initiation site for SV40 DNA replication. The latter segment was derived from the genome of a defective reiteration mutant of SV40 also by endo R. Hin dIII cleavage. When the recombinant molecule, together with wild-type SV40 DNA as helper, was introduced into monkey cells by DNA infection, replication of the λ-DNA sequences was observed, and hybrid genomes were encapsidated into progeny SV40 virions. The structure of the λ-DNA segment after serial passage in monkey cells was examined by use of restriction endonucleases and electron microscopic heteroduplex analysis.
Mathematical analysis of the relative contributions of decreased production and increased peripheral destruction in idiopathic thrombocytopenic purpura and implications in splenectomy.

We utilize a model of platelet concentration kinetics and bone marrow production based on three terms (a constant loss term, a random loss term and a higher order loss term) to compare a hypoplastic bone marrow patient and a patient with Idiopathic Thrombocytopenic Purpura (ITP) for the same platelet concentration. We compare this model to published data and show that in many ITP patients there is an overall decrease in platelet production. However, for almost all cases of ITP there is an increase in peripheral platelet destruction, even in those cases where total bone marrow production is less than that in a normal individual or is severely depressed. We are able to graphically depict the variable contributions of decreased production and increased peripheral destruction in patients with ITP and hence give insight into their relative contributions in a given patient. We apply a unique feature of our model, the newly postulated destruction term proportional to the platelet concentration squared (the higher order loss term), to explain cases of antibody negative ITP. Application of our model to data on patients splenectomized as treatment for ITP shows promise in predicting which patients are likely to respond.
Correction: Letter on Screening for Disability

To the Editors: In our response (1), the second sentence of the fourth paragraph should read as follows: "For example, in the meticulously done negative trial by Rubenstein and colleagues (2), the ...
Tristatic high resolution Doppler lidar to study winds and turbulence in the troposphere.

The implementation of a high resolution Doppler lidar (HRDL) to measure tropospheric winds and turbulence using a high resolution Fabry-Perot optical interferometer is considered. The Fabry-Perot detector system we have chosen is based on the one developed for passive wind measurements on board the Dynamics Explorer satellite. This is a stable high resolution system consisting of an optically contacted plane etalon and a multiring anode detector to scan spatially the image plane of the Fabry-Perot. The Doppler lidar proposed here consists of two transmitters and a receiver in a collinear arrangement. This system enables measurement of a horizontal and the vertical components of the wind in a common volume in space. The volume is determined by the intersection of the field of view of the receiver and the divergence of the laser beam.
Dynamic instabilities in the vortex lattice of YBa2Cu3O7−δ

Abstract A dynamic instability in the AC response of the vortex solid phase just below the melting/freezing line is reported. The instability takes the form of a voltage oscillation whose frequency is much lower than the driving frequency. The dependence of the voltage oscillation on experimental parameters is described.
Detecting and aligning peaks in mass spectrometry data with applications to MALDI

In this paper, we address the peak detection and alignment problem in the analysis of mass spectrometry data. To deal with the peak redundancy problem existing in the MALDI data acquired in the reflectron mode, we propose to use the amplitude modulation technique in peak detection. The alignment of two peak sets is formulated as a non-rigid registration problem and is solved using a robust point matching (RPM) approach. To align multiple peak sets, we first use a super set method to find a common peak set among all peak sets as a standard and then align all peak sets to the standard using the robust point matching approach in a sequential manner (i.e. We align only one peak set to the standard each time, thus reducing the multiple peak set alignment problem to a simpler two peak set alignment problem). Experimental results from a study of ovarian cancer data set show that the quantitative cross-correlation coefficients among technical replicates are increased after peak alignment. Additional comparisons also demonstrate that our method has a similar performance as the hierarchical clustering method, although the implementations of these methods are different.
Acute and multiple injection effects of magnesium of responding maintained by cocaine, extinction from cocaine, glucose + saccharin, and food

Abstract In a variety of behavioral experiments, magnesium has effects that are similar to cocaine and other psychomotor stimulants. Of particular relevance to the present experiments is the recent finding that magnesium maintains responding in cocaine-trained rats. It would be expected, therefore, that injections of magnesium would alter the rate of responding maintained by self-administered cocaine in rats. Five experiments examined the specificity and selectivity of this interaction. Acute and multiple injections of MgCl 2 (15–250 mg/kg) produced dose-dependent reductions in responding maintained by cocaine (0.1–2 mg/kg/infusion). Testing for acute injection effects occured following injections, while testing for multiple injection effects occured prior to daily injections. Doses of 30 and 125 mg/kg MgCl 2 reduced responding maintained by doses of cocaine that were below the training dose of 0.75 mg/kg/infusion. MgCl 2 in a dose of 250 mg/kg markedly suppressed responding maintained by each dose of cocaine. A magnesium-deficient diet produced a dose-dependent increase in responding maintained by 0.1 mg/kg/infusion cocaine. In order to determine the specificity and selectively of these effects, acute and multiple injections of MgCl 2 were examined on glucose + saccharin- and food-maintained responding. The acute effects of MgCl 2 injections were specific because food-maintained responding was not affected, except by the highest dose of 250 mg/kg. This demonstrates that lever pressing was not nonspecifically reduced by 30 and 125 mg/kg MgCl 2 during cocaine availability. However, the effects on cocaine-maintained responding were not selective for cocaine because glucose + saccharing-maintained responding and responding during extinction from cocaine were affected by MgCl 2 in a manner similar to cocaine-maintained responding. effects of MgCl 2 were both specific and selective for cocaine-maintained responding because multiple injections did not influence glucose + saccharin- or food-maintained responding.
Support vector machine classification of major depressive disorder using diffusion-weighted neuroimaging and graph theory

Recently there has been considerable interest in understanding brain networks in Major Depressive Disorder (MDD). Neural pathways can be tracked in the living brain using diffusion weighted imaging (DWI); graph theory can then be used to study properties of the resulting fiber networks. To date, global abnormalities have not been reported in tractography-based graph metrics in MDD, so we used a machine learning approach based on ‘support vector machines’ to differentiate depressed from healthy individuals based on multiple brain network properties. We also assessed how important specific graph metrics were for this differentiation. Finally, we conducted a local graph analysis to identify abnormal connectivity at specific nodes of the network. We were able to classify depression using whole-brain graph metrics. Small-worldness was the most useful graph metric for classification. The right pars orbitalis, right inferior parietal cortex, and left rostral anterior cingulate all showed abnormal network connectivity in MDD. This is the first use of structural global graph metrics to classify depressed individuals. These findings highlight the importance of future research to understand network properties in depression across imaging modalities, improve classification results, and relate network alterations to psychiatric symptoms, medication, and co-morbidities.
The electroreduction of heptaphenyltropylium ion to the free radical in acetonitrile

Abstract The reduction of heptaphenyltropylium ion (HPT+) in acetonitrile solutions containing 0.1 M tetra-n-butylammonium perchlorate at a platinum electrode was studied by cyclic voltammetry and controlled potential coulometry. A reversible wave for the production of the free radical at −1.20 V vs. SCE was observed. The radical was stable on the voltammetric time scale (∼ seconds) but decayed slowly. The production of a dimeric species involving coupling via the phenyl groups and reducible at about −1.9 V is proposed.
2-fluorourocanic acid, a potent reversible inhibitor of urocanase

The Ki for the interaction of 2-fluorourocanic acid with urocanase (from Pseudomonas fluorescens) is 1000 times as great as Km for the natural substrate, urocanic acid, whereas enzymatic hydration of the fluoro analog occurs ca. 100 times more slowly. Inhibition is competive and is eventually overcome by utilization of the analog. By contrast, 4-fluoro- and 2-amino-urocanic acid are neither significant inhibitors nor substrates for the enzyme. 2-Fluorourocanic acid may prove a useful tool for blocking the utilization of histidine as a one-carbon source in metabolism.
Late postoperative tamponade following coronary artery bypass grafting in patients on antiplatelet therapy.

Abstract Myocardial revascularization was performed in 1,361 patients over a 66-month period (February, 1978 to August, 1983) without a single occurrence of late cardiac tamponade. During a subsequent 4-month-period, aspirin and dipyridamole were administered routinely to all coronary bypass patients. The incidence of late cardiac tamponade rose significantly ( p
Crystal structures of cytochrome P450 2B4 in complex with the inhibitor 1-biphenyl-4-methyl-1H-imidazole: ligand-induced structural response through alpha-helical repositioning.

Two different ligand occupancy structures of cytochrome P450 2B4 (CYP2B4) in complex with 1-biphenyl-4-methyl-1H-imidazole (1-PBI) have been determined by X-ray crystallography. 1-PBI belongs to a series of tight binding, imidazole-based CYP2B4 inhibitors. 1-PBI binding to CYP2B4 yields a type II spectrum with a Ks value of 0.23 μM and inhibits enzyme activity with an IC50 value of 0.035 μM. Previous CYP2B4 structures have shown a large degree of structural movement in response to ligand size. With two phenyl rings, 1-PBI is larger than 1-(4-chlorophenyl)imidazole (1-CPI) and 4-(4-chlorophenyl)imidazole (4-CPI) but smaller than bifonazole, which is branched and contains three phenyl rings. The CYP2B4−1-PBI complex is a structural intermediate to the closed CPI and the open bifonazole structures. The B/C-loop reorganizes itself to include two short partial helices while closing one side of the active site. The F−G-helix cassette pivots over the I-helix in direct response to the size of the ligand in the ac...
Angle-resolved scattering spectroscopy of explosives using an external cavity quantum cascade laser

We present a study of the spectral and angular dependence of the diffuse scatter of mid-infrared (MIR) laser light from explosives residues on surfaces. Experiments were performed using an external cavity quantum cascade laser (ECQCL) tunable between 7 and 8 μm (1270 to 1400 cm-1) for surface illumination. A mercury cadmium telluride (MCT) detector was used to detect backscattered spectra as a function of surface angle at a 2 meter standoff. A ferroelectric focal plane array was used to build hyperspectral images at a 0.5 meter standoff. Residues of RDX, tetryl, and TNT were investigated on surfaces including a painted car door for angles between zero (specular) and 50 degrees. We observe spectral signatures of the explosives in the diffuse scattering geometry which differ significantly from those observed in transmission geometries. Characterization of the scattered light spectra of explosives on surfaces will be essential for understanding the performance of standoff explosives detection instruments and developing robust spectral analysis techniques.
A model-driven blocking strategy for load balanced sparse matrix-vector multiplication on GPUs

Sparse Matrix-Vector multiplication (SpMV) is one of the key operations in linear algebra. Overcoming thread divergence, load imbalance and un-coalesced and indirect memory access due to sparsity and irregularity are challenges to optimizing SpMV on GPUs.In this paper we present a new Blocked Row-Column (BRC) storage format with a two-dimensional blocking mechanism that addresses these challenges effectively. It reduces thread divergence by reordering and blocking rows of the input matrix with nearly equal number of non-zero elements onto the same execution units (i.e., warps). BRC improves load balance by partitioning rows into blocks with a constant number of non-zeros such that different warps perform the same amount of work. We also present an approach to optimize BRC performance by judicious selection of block size based on sparsity characteristics of the matrix.A CUDA implementation of BRC outperforms NVIDIA CUSP and cuSPARSE libraries and other state-of-the-art SpMV formats on a range of unstructured sparse matrices from multiple application domains. The BRC format has been integrated with PETSc, enabling its use in PETSc's solvers. Furthermore, when partitioning the input matrix, BRC achieves near linear speedup on multiple GPUs. A novel blocking strategy that reduces thread divergence and improves load balance.Enhanced performance modeling for selection of a key blocking parameter.An efficient auto-tuning technique to optimize performance.Comprehensive experimental evaluation and integrating with a real system; PETSc.A multi-GPU algorithm for SpMV with experimental evaluation.
Organizational graffiti : A different approach to uncovering issues

An exercise with variations is presented in which group members are encouraged to generate graffiti (sayings, slogans, pictures, symbols) so that organizational issues can be reflected in interesting and attention-getting ways. Comments on risks of this exercise and the roles of the facilitator and of the group are included.
The Reintegration of Technology as a Function of Curriculum Reform: Cases of Two Teachers

The study utilized a case study approach to investigate the change in technology use of two teachers of elementary-aged students with moderate to severe disabilities during the first year of a multi-year professional development and research project. Participants in a larger multi-year professional development and research project focused on increasing educators’ capacity to provide comprehensive literacy instruction to their students; these teachers self-identified as interested in technology as a support for their students’ participation during instruction. Data sources included field notes and logs, interviews, classroom observations, photographs and video of instruction, and document review. The teachers made substantive changes in their literacy instruction as well as the technology tools they used to engage students instructionally. Two themes emerged from the data as influencers of technology integration: (a) the evolving nature of curriculum reform and (b) ongoing interdisciplinary collaboration. ...
Adducts of copper(II) β-diketone chelates with tertiary alkylamines and alkylamine hydrochlorides☆

Abstract Adduct formation of Cu(chelate)2 (chelate = anion of thenoyltrifluoroacetone, TTA, and trifluoroacetylacetone, TFA) with alkylamines and alkylamine hydrochlorides, S (S = tri-n-butylamine, TBA, tri-n-hexylamine, THA, tri-n-octylamine, TOA, tri-n-laurylamine, TLA, tri-n-hexylamine hydrochloride, THA·HCl, tri-n-octylamine hydrochloride, TOA·HCl and tri-n-laurylamine hydrochloride, TLA·HCl) have been studied spectrophotometrically. Visible and i.r. spectra suggest that alkylamines and alkylamine hydrochlorides form different adducts through bonding of different atoms. In the alkylamines the nitrogen atom is bonded to copper(II) while in the alkylamine hydrochlorides the chlorine atom is bonded to copper(II). Equilibrium constants for the adduct-formation reactions are calculated from the spectral change upon addition of the adduct-forming ligands. It is found that alkylamines and alkylamine hydrochlorides do not interact with Cu(chelate)2 to the same extent. Furthermore, the complexes species, TOA·HTTA and TOA·HCl·HTTA, do not interact with Cu(chelate)2.
Osthole activates glucose uptake but blocks full activation in L929 fibroblast cells, and inhibits uptake in HCLE cells.

Aims Osthole, a coumarin derivative, has been used in Chinese medicine and studies have suggested a potential use in treatment of diabetes and cancers. Therefore, we investigated the effects of osthole and other coumarins on GLUT1 activity in two cell lines that exclusively express GLUT1.
Numerical Model of Full-Cardiac Cycle Hemodynamics in a Total Artificial Heart and the Effect of Its Size on Platelet Activation

The SynCardia total artificial heart (TAH) is the only Food and Drug Administration (FDA) approved device for replacing hearts in patients with congestive heart failure. It pumps blood via pneumatically driven diaphragms and controls the flow with mechanical valves. While it has been successfully implanted in more than 1300 patients, its size precludes implantation in smaller patients. This study’s aim was to evaluate the viability of scaled-down TAHs by quantifying thrombogenic potentials from flow patterns. Simulations of systole were first conducted with stationary valves, followed by an advanced full-cardiac cycle model with moving valves. All the models included deforming diaphragms and platelet suspension in the blood flow. Flow stress accumulations were computed for the platelet trajectories and thrombogenic potentials were assessed. The simulations successfully captured complex flow patterns during various phases of the cardiac cycle. Increased stress accumulations, but within the safety margin of acceptable thrombogenicity, were found in smaller TAHs, indicating that they are clinically viable.
Retention of an incompletely learned avoidance response: Some problems with replication

Eight experiments, each designed to determine the cause of failure to replicate the “Kamin-effect” were performed. Replication was finally obtained for Experiments VII and VIII in which original avoidance training was carried to only one successful avoidance. Under this criterion there was little or no overlap in the combined performances of groups retrained at.08 and 24 hr. intersession intervals with those retrained at 1 and 4 hr. periods.
Economics of compressed air energy storage to integrate wind power: A case study in ERCOT

Abstract Compressed air energy storage (CAES) could be paired with a wind farm to provide firm, dispatchable baseload power, or serve as a peaking plant and capture upswings in electricity prices. We present a firm-level engineering-economic analysis of a wind/CAES system with a wind farm in central Texas, load in either Dallas or Houston, and a CAES plant whose location is profit-optimized. With 2008 hourly prices and load in Houston, the economically optimal CAES expander capacity is unrealistically large – 24 GW – and dispatches for only a few hours per week when prices are highest; a price cap and capacity payment likewise results in a large (17 GW) profit-maximizing CAES expander. Under all other scenarios considered the CAES plant is unprofitable. Using 2008 data, a baseload wind/CAES system is less profitable than a natural gas combined cycle (NGCC) plant at carbon prices less than $56/tCO 2 ($15/MMBTU gas) to $230/tCO 2 ($5/MMBTU gas). Entering regulation markets raises profit only slightly. Social benefits of CAES paired with wind include avoided construction of new generation capacity, improved air quality during peak times, and increased economic surplus, but may not outweigh the private cost of the CAES system nor justify a subsidy.
A hybrid visualization system for molecular models

Nowadays, 3D visualization is part of our everyday lives and remains an important tool for understanding complex structures, dynamic simulations, and research discoveries. In the meantime, the complexity of the visualization often requires specific hardware, including visualization clusters, as well as dedicated software tools. Several efforts, such as WebGL and remote visualization, have been pushing visualization to the web browser. However, technical limitations have constrained the adoption of web browsers as a means of rendering 3D datasets. To surpass these limitations, prospective action has been recently initiated with the development of a web application based on two innovative technologies: WebGL and ParaViewWeb. This application combines the benefits of local and remote rendering, therefore allowing a user to visualize small to massive 3D molecular datasets on a large number of devices. To demonstrate this approach a prototype has been developed, and in this paper we present the hybrid architecture of the proposed system, the initial implementation experiment, and a comparison with current technologies. Finally, we discuss the future work and potential improvements of the application.
Reactions of M2Cl4(PR3)4 (M Mo and W) with carbon monoxide

Abstract The reactions of M 2 Cl 4 (PR 3 ) 4 derivatives (M  Mo, W and PR 3  PEt 3 , PBu 3 n ) with CO at atmospheric pressure in toluene at 70°C to afford M(CO) 3 (PR 3 ) 2 Cl 2 and trans -M(CO) 4 (PR 3 ) 2 are reported.
Parent willingness to remind health care workers to perform hand hygiene

Background Health care worker (HCW) hand hygiene (HH) is the core strategy to prevent health care-associated infections (HAI). Suboptimal HCW HH rates continue despite hospital efforts to increase compliance. Objectives To determine whether parents of hospitalized children perceive they have a role in preventing HAI and whether they are willing to remind HCW to perform HH, with and without an invitation. Methods We conducted structured interviews of parents of children admitted to a pediatric hospital. Questions assessed knowledge, attitudes, and behaviors about HAI and HH. The primary outcome was willingness to remind a HCW to do HH (5-point Likert scale). Results We interviewed 115 parents, of whom 84% were aware of HAI. Most parents (78%) perceived HH as the most important practice to prevent HAI. However, only 67% would definitely remind a HCW to perform HH. Importantly, 92% said that an invitation from a HCW would make them more likely to remind a HCW to do HH in the future. Conclusion Our results suggest that parents of hospitalized children are willing to help prevent HAI; however one-third are still reluctant to remind HCW to perform HH. An invitation by HCW to parents to remind HCW to perform HH might effectively engage parents as partners in HAI prevention.
Kinetics of Hb S gelation Effect of alkylureas, ionic strength and other hemoglobins

Using a light scattering (turbidity) method to estimate the delay time of gelation of deoxy hemoglobin S hemolysates, we have examined the effects of various alkylureas, variations in ionic strength by addition of NaCl, and admixture with other hemoglobins on gelation kinetics. Each of these factors substantially prolonged the delay times to different extents, but the dependence of the delay times on a high power of the hemoglobin concentration varied only slightly. These findings suggest that the events preceding gelation, most likely the formation of nuclei, are affected by these factors, but the critical nuclear size for gelling is fairly constant. Parallel changes indicated good qualitative correlation between gelation, delay times, minimum gelling concentrations of solutions of mixed hemoglobins and kinetics of sickling of red cells containing these mixtures, with the exception of hemoglobin Charlem trait cells the sickling kinetics of which were slower than predicted by the solution properties.
Departmental morale as a function of the perceived performance of department heads

The object of this paper is to analyze some of the factors underlying differing levels of morale in university departments. Morale is conceived to be primarily a product of perceived department-head performance, although it is also suggested that environmental and satisfaction variables may be important. Morale is seen as a potential symptomatic attribute which might be used in diagnosing organizational difficulties. The authors did indeed find, using multiple discriminant analysis on departmentally aggregated data, that the perceived performance of department heads was more important in predicting levels of morale. In addition, department size was also found to be useful. The conclusions drawn were that morale could be used as a symptom of departmental (or organizational) well being and that such data could be useful to those managing department heads both in the selection of department heads and in their ongoing supervision.
Destabilization is as important as binding

Enzymes make use of non-covalent interactions with their substrates to bring about a large fraction of their catalytic activity. These interactions must destabilize, or increase the Gibbs energy, of the substrate in the active site in order that the transition state can be reached easily. This destabilization may be brought about by utilization of the intrinsic binding energy between the active site and the bound substrate by desolvation of charged groups, geometric distortion, electrostatic interactions and, especially, loss of entropy in the enzyme-substrate complex. These mechanisms are described by interaction energies and require utilization of the intrinsic binding energy that is realized from non-covalent interactions between the enzyme and substrate. Receptors and coupled vectorial processes, such as muscle contraction and active transport, utilize binding energy similarly to avoid large peaks and valleys along the Gibbs energy profile of the reaction under physiological conditions.
Sphingosine-1-phosphate receptor signalling in the heart

The five known members of the sphingosine-1-phosphate (S1P) receptor family exhibit diverse tissue expression profiles and couple to distinct G-protein-mediated signalling pathways. S1P1, S1P2, and S1P3 receptors are all present in the heart, but the ratio of these subtypes differs for various cardiac cells. The goal of this review is to summarize data concerning which S1P receptor subtypes regulate cardiac physiology and pathophysiology, which G-proteins and signalling pathways they couple to, and in which cell types they are expressed. The available information is based on studies using a lamentably limited set of pharmacological agonists/antagonists, but is complemented by work with S1P receptor subtype-specific knockout mice and sphingosine kinase knockout mice. In cardiac myocytes, the S1P1 receptor subtype is the predominant subtype expressed, and the activation of this receptor inhibits cAMP formation and antagonizes adrenergic receptor-mediated contractility. The S1P3 receptor, while expressed at lower levels, mediates the bradycardic effect of S1P agonists. Studies using knockout mice indicate that S1P2 and S1P3 receptors play a major role in mediating cardioprotection from ischaemia/reperfusion injury in vivo. S1P receptors are also involved in remodelling, proliferation, and differentiation of cardiac fibroblasts, a cell type in which the S1P3 receptor predominates. Receptors for S1P are also present in endothelial and smooth muscle cells where they mediate peripheral vascular tone and endothelial responses, but the role of this regulatory system in the cardiac vasculature is unknown. Further understanding of the contributions of each cell and receptor subtype to cardiac function and pathophysiology should expedite consideration of the endogenous S1P signalling pathway as a therapeutic target for cardiovascular disease.