bluuebunny/crossref_metadata_2025_split huggingface dataset:
Discordant aPTT and Anti-Xa Values and Outcomes in Hospitalized Patients Treated with Intravenous Unfractionated Heparin
Authors: Price Elizabeth A , Jin Jing , Nguyen Huong Marie , Krishnan Gomathi , Bowen Raffick , Zehnder James L 
Published: February 2013

BACKGROUND: Both the activated partial thromboplastin time (aPTT) and anti-Xa assay can be used to monitor unfractionated heparin (UFH). Following implementation of an anti-Xa method for heparin dosing protocols in our hospital, we became aware of many patients with discordant aPTT and anti-Xa values. OBJECTIVE: To determine the frequency of discordant aPTT and anti-Xa values in a large cohort of hospitalized patients treated with UFH, as well as the demographics, coagulation status, indication for UFH, and clinical outcomes in this population. METHODS: All aPTT and anti-Xa values from adults hospitalized between February and August 2009 at Stanford Hospital who were treated with UFH were analyzed. All samples were drawn simultaneously. A polynomial fit correlating aPTT and anti-Xa with a 99% confidence limit was designed. Paired aPTT/anti-Xa values were grouped according to whether the paired values fell within or outside of the concordant area. Patients were placed into groups based on concordance status, and clinical outcomes were assessed. RESULTS: A total of 2321 paired values from 539 patients were studied; 42% of data pairs had a high aPTT value relative to the anti-Xa value. Patients with elevated baseline prothrombin time/international normalized ratio or aPTT frequently demonstrated disproportionate relative prolongation of the aPTT. Patients with at least 2 consecutive high aPTT to anti-Xa values had increased 21-day major bleeding (9% vs 3%; p = 0.0316) and 30-day mortality (14% dead vs 5% dead at 30 days; p = 0.0202) compared with patients with consistently concordant values. CONCLUSIONS: aPTT and anti-Xa values are frequently discordant when used to measure UFH in hospitalized patients. A disproportionate prolongation of the aPTT relative to the anti-Xa was the most common discordant pattern in our study. Patients with relatively high aPTT to anti-Xa values appear to be at increased risk of adverse outcomes. Monitoring both aPTT and Xa values may have utility in managing such patients.
Sex-Induced Silencing Operates During Opposite-Sex and Unisexual Reproduction in Cryptococcus neoformans
Authors: Wang Xuying , Darwiche Sabrina , Heitman Joseph 
Published: February 2013

Abstract
Cryptococcus neoformans is a human fungal pathogen that undergoes a dimorphic transition from yeast to hyphae during a-α opposite-sex mating and α-α unisexual reproduction (same-sex mating). Infectious spores are generated during both processes. We previously identified a sex-induced silencing (SIS) pathway in the C. neoformans serotype A var. grubii lineage, in which tandem transgene arrays trigger RNAi-dependent gene silencing at a high frequency during a-α opposite-sex mating, but at an ∼250-fold lower frequency during asexual mitotic vegetative growth. Here we report that SIS also operates during α-α unisexual reproduction. A self-fertile strain containing either SXI2a-URA5 or NEO-URA5 transgene arrays exhibited an elevated silencing frequency during solo and unisexual mating compared with mitotic vegetative growth. We also found that SIS operates at a similar efficiency on transgene arrays of the same copy number during either α-α unisexual reproduction or a-α opposite-sex mating. URA5-derived small RNAs were detected in the silenced progeny of α-α unisexual reproduction and RNAi core components were required, providing evidence that SIS induced by same-sex mating is also mediated by RNAi via sequence-specific small RNAs. In addition, our data show that the SIS RNAi pathway also operates to defend the genome via squelching transposon activity during same-sex mating as it does during opposite-sex mating. Taken together, our results confirm that SIS is conserved between the divergent C. neoformans serotype A and serotype D cryptic sibling species.
Characterization of Thin ZnO Films by Vacuum Ultra-Violet Reflectometry
Authors: Gumprecht T. , Petrik P. , Roeder G. , Schellenberger M. , Pfitzner L. , Pollakowski B. , Beckhoff B. 
Published: February 2013

ABSTRACTZnO has a huge potential and is already a crucial material in a range of key technologies from photovoltaics to opto and printed electronics. ZnO is being characterized by versatile metrologies to reveal electrical, optical, structural and other parameters with the aim of process optimization for best device performance. The aim of the present work is to reveal the capabilities of vacuum ultra-violet (VUV) reflectometry for the characterization of ZnO films of nominally 50 nm, doped by Ga and In. Optical metrologies have already shown to be able to sensitively measure the gap energy, the exciton strength, the density, the surface nanoroughness and a range of technologically important structural and material parameters. It has also been shown that these optical properties closely correlate with the most important electrical properties like the carrier density and hence the specific resistance of the film. We show that VUV reflectometry is a highly sensitive optical method that is capable of the characterization of crucial film properties. Our results have been cross-checked by reference methods such as ellipsometry and X-ray fluorescence.
Diffusion brazing of γ-TiAl-alloys: Investigations of the joint by electron microscopy and high-energy X-ray diffraction
Authors: Hauschildt Katja , Stark Andreas , Lorenz Uwe , Schell Norbert , Fischer Torben , Blankenburg Malte , Mueller Martin , Pyczak Florian 
Published: February 2013

ABSTRACTDiffusion brazing is a potential method to repair parts made from TiAl-alloys. Two different brazing materials with varying contents of titanium, iron and nickel were investigated. The phases present in the brazed zone were identified by high energy X-ray diffraction (HEXRD) at the material science beamline HEMS at the PETRA III synchrotron facility at DESY in Hamburg, Germany, and the microstructure was characterised by scanning electron microscopy (SEM). The braze zone itself is composed of one to two transitional layers from the substrate material to the middle of the joint. Near the substrate material the phase constitution reassembles a TiAl-alloy while the middle of the joint is similar to α/β-titanium alloys. Besides phases commonly encountered in TiAl-alloys such as γ, α2 and β, additional phases, which are related to the presence of nickel or iron as melting point depressing elements are present. The microstructure of the brazed zone changes significantly during a subsequent heat treatment.
Toward an Inverse Approach for the Design of Small-Molecule Fixating Catalysts
Authors: Weymuth Thomas , Reiher Markus 
Published: February 2013

ABSTRACTWithin an inverse design approach applied to a nitrogen-fixation catalyst we discuss options for calculating “jacket” potentials that fulfill a purpose-oriented target requirement. As a target requirement we choose the vanishing geometric gradients on all atoms of a subsystem consisting of a metal center binding the small molecule to be activated - in our case dinitrogen. The additional potential can be represented within a full quantum model or by a sequence of approximations of which a field of electrostatic point charges is the simplest. In order to analyze the feasibility of this approach, we dissect a known dinitrogen-fixating complex and analyze its ligand environment expressed by the “jacket” potential. It is discussed how this ligand-bypotential replacement can be generalized for future applications that eventually allow us to find a competitive synthetic nitrogen-fixation transition metal complex. It can be expected that such a ligand-by-potential replacement approach will be applicable to any type of host-guest chemical process.
Microstructure and Local Charge Distribution in Hydrogenated Nanocrystalline Silicon under Illumination Studied by Electrostatic Force Microscopy.
Authors: Priti Rubana Bahar , Bommisetty Venkat 
Published: February 2013

ABSTRACTHydrogenated nanocrystalline silicon (nc-Si:H) is a promising absorber material for photovoltaic applications. Nanoscale electrical conductivity and overall electronic quality of this material are significantly affected by film microstructure, specifically the density and dimension of grains and grain-boundaries (GB). Local charge distribution at grains and grain/GB interfaces of nc-Si:H was studied by Electrostatic Force Microscopy (EFM) in constant force mode under illumination of white LED. Bias voltage from -3V to +3V was applied on the tip. Scanning Kelvin Force (KFM) images were taken before and after illumination to study the change in surface photovoltage (SP). EFM and KFM analysis were combined with film topography to draw a correlation between surface morphology and nanoscale charge distribution in this material. After illumination, small blister like structures were observed whose size and density increase with time. Raman spectroscopy confirmed these new structures as nanocrystalline silicon. This change was assumed due to relaxation of strained Si-Si bonds as an effect of photo response. Nanocrystalline grain interiors were at lower potential and amorphous grain boundaries were at higher potential for negative bias; it was opposite for positive bias. Change in polarity in bias voltage reversed the polarity of the potential in grains and GBs indicating the dominance of negative type of defects. Further study with current sensing AFM in dark and illumination with variable bias voltages will be able to identify the type and density of defects in grains and grain/GB interfaces.
Sputter deposited ZnO porous films for sensing applications
Authors: Borysiewicz Michał A. , Dynowska Elżbieta , Kolkovsky Valery , Wielgus Maciej , Gołaszewska Krystyna , Kamińska Eliana , Ekielski Marek , Struk Przemysław , Pustelny Tadeusz , Piotrowska Anna 
Published: February 2013

ABSTRACTNanoporous ZnO films are fabricated using a two step approach: sputter deposition of porous Zn followed by an ex-situ annealing in an oxygen flow at 400°C. The created structures have a porosity of 34% enabling use in surface-based absorption sensors. The films are used in a resistance-based sensor allowing easy discrimination between liquid methanol and ethanol by resistance measurements and also in a transmission-based sensor to detect NO2, NH3 and H2 gases in concentration as low as 500 ppm.
Introducing Antibacterial Properties to Paper Towels Through the Use of Selenium Nanoparticles
Authors: Wang Qi , Webster Thomas J. 
Published: February 2013

ABSTRACTBacterial infections are commonly found on paper towels and other paper products leading to the potential spread of bacteria and consequent health concerns. The objective of this in vitro study was to introduce antibacterial properties to paper towel surfaces by coating them with selenium nanoparticles. Scanning electron microscopy was used to measure the size and distribution of the selenium coatings on the paper towels. Atomic force microscopy was used to measure the surface roughness of paper towels before and after coated with selenium nanoparticles. The amount of selenium precipitated on the paper towels was measured by atomic absorption spectroscopy. In vitro bacterial studies with Staphylococcus aureus were conducted to assess the effectiveness of the selenium coating at inhibiting bacterial growth. Results showed that the selenium nanoparticles coated on the paper towel surface were well distributed and semispherical about 50nm in diameter. Most importantly, the selenium nanoparticle coated paper towels inhibited S. aureus growth by 90% after 24 hours and 72 hours compared with the uncoated paper towels. Thus, the study showed that nano-selenium coated paper towels may lead to an increased eradication of bacteria to more effectively clean a wide-range of clinical environments, thus, improving health.
Modelling the Activation of H2 on Spent Fuel Surface and Inhibiting Effect of UO2 Dissolution
Authors: Duro L. , Riba O. , Martínez-Esparza A. , Bruno J. 
Published: February 2013

ABSTRACTThe dissolution of spent nuclear fuel is defined in two different time steps, i) the Instant Release Fraction (IRF) occurring shortly after water contacts the solid spent fuel and responsible of the fast release of those radionuclides that have been accumulated in the zones of the spent fuel pellet with low confinement, such as gap and grain boundaries and ii) the long term release of radionuclides confined in the spent fuel matrix, much slower and dependent on the conditions of the water that contacts the spent fuel.Several models have been developed to date to explain the dissolution behavior of spent nuclear fuel under disposal conditions. The Matrix Alteration Model (MAM) is one of the most evolved radiolytic models describing the dissolution mechanism in which an Alteration/Dissolution source term model is based on the oxidative dissolution of spent fuel. Under deep repository conditions and at the expected of water contacting time (after 1000 years of spent fuel storage), α radiation will be the main contributor to water radiolysis. In the current study, simulations evaluating the effect of surface area on the alteration/dissolution of spent fuel matrix are performed considering different particle sizes of spent fuel and simulations integrating the actinides dissolution have been performed considering the precipitation of secondary phases.
Corrosion Study of SIMFUEL in Aerated Carbonate Solution Containing Calcium and Silicate
Authors: Jung Hundal , Ahn Tae , Pabalan Roberto , Pickett David 
Published: February 2013

ABSTRACTThe corrosion behavior of simulated spent nuclear fuel (SIMFUEL) was investigated using electrochemical impedance spectroscopy and solution chemistry analyses. The SIMFUEL was exposed to aerated solutions of NaCl+NaHCO3 with and without calcium (Ca) and silicate. Two SIMFUEL compositions were studied, representing spent nuclear fuel (SNF) corresponding to 3 or 6 at % burnup in terms of fission product equivalents of surrogate elements. For all tested cases, the polarization resistance increased with increased immersion time, indicating possible blocking effects due to accumulation of corrosion products on the SIMFUEL surface. The potential-pH diagram suggests formation of schoepite that may cause the increase in the polarization resistance. The addition of Ca and silicate produced no measureable change in the polarization resistance measured at the corrosion potential. The dissolution rate ranged from 1 to 3 mg/m2-day, which is similar to the range of dissolution rates for SIMFUEL and SNF reported in the literature for comparable conditions. SIMFUEL burnup did not have a major effect on the dissolution rate. Analysis of the solution chemistry shows that uranium is the dominant element dissolved in the posttest solutions, and the dissolution rates calculated from uranium (U) concentrations are consistent with the dissolution rates obtained from impedance measurements. Simulated-fission product elements (i.e., barium, molybdenum, strontium, and zirconium) dissolved from the SIMFUEL electrode at a relatively high rate. Sorption test results indicated significant sorption of U onto the oxide formed on stainless steel. Electrochemical methods were found to be effective for measuring the uranium dissolution rate in real time.
A breakup model of Jetting formation of Explosively Loaded Granular Shells
Authors: Xue Kun 
Published: February 2013

ABSTRACTThis paper investigates the underlying physics governing the explosion driven expansion and fragmentation of spherical beds packed of partially saturated sand with varying mass fractions of interstitial oil. The breakup onset of the sand shells is characterized by the formation of fragments/agglomerates consisting of a large number of constituent grains, which in later time present themselves as prolific and regular jetting streams. Test data show a postponed jetting formation when sand shells are subject to the explosion with a higher detonation velocity, meanwhile a reduced jet mass scale is observed. A kinetic energy driven breakup model is proposed based on the instability criterion involving the opposing forces of stabilizing inertial pressures and destabilizing viscous resistance. This analytical model is capable of predicting the onset of granular material fragmentation as well as the characteristic fragment size, which is consistent with the experimental results.
Visualization of the Fetal Lip and Palate: Is Brain-Targeted MRI Reliable?
Authors: Moreira Nuno Canto , Ribeiro Valentina , Teixeira João , Raininko Raili , Wikstrom Johan 
Published: February 2013

Objective To evaluate the ability of brain-targeted magnetic resonance imaging (MRI) to assess the anatomy of the fetal upper lip and palate. Design Two independent readers made a blind retrospective review of 60 brain-targeted MRIs of fetuses from 20 to 38 gestational weeks (GW). Fifty-five MRIs were normal and five had orofacial anomalies, including one isolated cleft lip and four cleft lip and palate. Both normal and cleft MRIs had postnatal confirmation. The upper lip, primary palate, secondary palate, and nasal septum were scored into four levels, from evidently normal to evidently abnormal. In case of a suspected pathology, the readers attempted a diagnosis. Setting Collaboration between a university hospital and a large private practice MRI center. Results Interobserver agreement (weighted kappa) was 0.79 for the upper lip, 0.70 for the primary palate, 0.86 for the secondary palate, and 0.90 for the nasal septum. The scoring levels of the readers did not change significantly across gestational age. Normality was correctly scored in 96% to 100% of the normal lips and primary palates and in 93% to 97% of the normal secondary palates depending on the reader. A deviated septum was only scored in two fetuses with unilateral cleft palates. The readers identified all pathological cases. Conclusion Brain-targeted fetal MRI in experienced hands seems to be highly accurate for the evaluation of the lip and palate in fetuses above 20 GW, regardless of gestational age. The assessment of the secondary palate may be slightly more limited than the lip or primary palate.
Genetic and Genotype × Environment Interaction Analysis for Agronomical and Some Morphological Traits in Half‐Sib Families of Tall Fescue
Authors: Amini Fatemeh , Majidi Mohammad Mahdi , Mirlohi Aghafakhr 
Published: February 2013

ABSTRACTTall fescue (Festuca arundinacea Schreb.) is an outcrossing allohexaploid grass species extensively used for forage and turf worldwide. Twenty‐five genotypes of tall fescue were chosen from a broad‐base population and the genetic diversity was evaluated based on expressed sequence tag‐simple sequence repeat molecular markers and agronomical and morphological traits. Their respective half‐sib polycross progenies were also evaluated for these same traits at six environments (two locations for 3 yr). The high genotypic variation observed for plant seed yield and some morphological traits in parental genotypes and their respective progenies indicated high potential for improving these traits through targeted selection in breeding programs. Family and family × location interactions were significant for most characteristics. Narrow‐sense heritability estimates were moderately high for plant seed weight (49%), number of fertile tillers (46%), panicle length (45%), and plant height (44%). These indicate that family selection methods should be more effective than individual selection. Stable families across environments were identified based on the regression coefficients, deviations from the regression, and yield potential indicating the usefulness of these parameters in the selection process for seed and forage yield improvement where additive × environment interactions are present.
Development of Functional Molecular Markers of SbeI and SbeIIb for the High Amylose Maize Germplasm Line GEMS‐0067
Authors: Chen Tingting , Ning Lihua , Liu Xu , Cui Dezhou , Zhang Hua , Li Detao , Zhao Li , Chen Huabang 
Published: February 2013

ABSTRACTThe development of high amylose corn (Zea mays L.) in the public sector has been hindered by the lack of high amylose germplasm available to breeders and difficulties in accurate and efficient amylose content measurement. GEMS‐0067 is the first public germplasm that possesses recessive amylose‐extender (ae) gene and a modifier gene or genes that raises amylose level to over 70%. Several lines of evidences suggested that SbeI is one of the major modifier genes for high amylose corn, and our work for the first time showed that SbeI explained 49% of the total amylose variance in the amylose extender background. We developed and validated functional codominant molecular markers of SbeI and SbeIIb for GEMS‐0067 that were able to distinguish AeAe, Aeae, and aeae genotypes. These simple, sequence‐specific, polymerase chain reaction‐based, low‐cost markers amenable to larger numbers of plant samples make them potentially viable for marker‐assisted selection in practical high amylose corn breeding programs. GEMS‐0067 was of mixed heterotic derivation. Our result clearly showed that GEMS‐0067 was genetically more similar to Mo17 and was clustered into non‐Stiff Stalk heterotic group based on 25 simple sequence repeat profiles. The information provided here would facilitate the development of high amylose corn.
Management of Native Soil Nitrogen for Reducing Nitrous Oxide Emissions and Higher Rice Production
Authors: Pandey Keshav R. , Shah S. C. , Becker M. 
Published: February 2013

Present production of rice is far below its reported potential yield because of being Ndeficiency, the major constraint. Because of poverty, small farmers have to rely on native soil N-supply. Between wheat harvest and rice transplanting, a dry-to-wet season transition (DWT) period exist with changing soil moisture from aerobic to anaerobic and a large amount of native soil N loss is hypothesized. To study soil N dynamism and possible management options for DWT, two years field experiments were conducted in Chitwan with four land management treatments like bare fallow, mucuna, mungbean and maize. Treatments were randomly allotted in 10 m<sup>2</sup> plots. During DWT, building up of 50-75 kg of nitrate-N was observed at 60-75 % field capacity (FC) soil moisture but lost after flooding through leaching and denitrification, resulting in low grain yield and N uptake of succeeding rice. Growing cover crops during DWT, reduced leaching loss by half and N2O emissions by two thirds of those in the bare fallows. Atmospheric-N addition by legumes ranged from 27 to 56 kg ha-1 depending on the types of legumes and increased N uptake and grain yield by 24-42 kg N ha-1 yr-1 and 1.2-2.1 Mg ha-1 yr-1respectively. Thus, cultivation of grain/green manure legumes appears economically and ecologically beneficial.Key Words: bare fallow, crop N uptake, denitrification, green manure, leaching, nitrate catch crops, nitrificationThe Journal of Agriculture and Environment Vol:9, Jun.2008 Page: 1-9
Standard Setting on Pesticide Residues to Ensure Food Safety
Authors: Lama Jiwan Prava 
Published: February 2013

This article highlights some aspects of pesticides contamination in foods and the Government of Nepal's experience in setting MRLs of pesticide on Food. Use of pesticides in agriculture crop has a great concern to all. According to the provision conferred by Food Law, Government of Nepal fixes MRLs of pesticide on food products. Potential products liable for pesticide use gets priority in standard setting. The problem of pesticides begins at the farm level and continues at different stage of handling and storage. Therefore, effective coordination between stakeholders working with different stages of food handling must collaborate to solve this problem. In this connection, some major issues and recommendations in managing proper use of pesticides are highlighted.Key words: Pesticides, maximum residue limits (MRLs), Food safety and qualityThe Journal of Agriculture and Environment Vol:.9, Jun.2008 Page: 46-53