915 research outputs found

    A simulation of weak-light phase-locking for space laser interferometer

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    A simulation was investigated to better understand the impacts and effects of the additional technical noises on weak-light phase-locking for space laser interferometer. The result showed that the locking precision was limited by the phase readout noise when the laser frequency noise and clock jitter noise were removed, and this result was then confirmed by a benchtop experimental test. The required space laser interferometer noise floor was recovered from the simulation which proved the validity of the simulation program. © Published under licence by IOP Publishing Ltd.National Natural Science Foundation of China/61575209Chinese Academy of Sciences/XDB2303020

    Determination of folic acid and its related substances of the ferrous fumarate and folic acid dispersible tablet by HPLC

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    The aim of the present study was to establish a method for the determination of folic acid and related substances content in dispersible tablets. Method: A Shim-pack VP-ODS C18 reversed phase column (4.6 mm × 250 mm) was used. The mobile phase consisted of methanol-phosphate buffer (20:80) with a pH of 6.3.The flow rate was 1.0 mL/min, and the detection wavelength was 277nm and the column temperature was 30 °C. Results: The calibration curve was linear in the range of 5~150 μg/mL (r = 0.9998) for folic acid. The minimal detection limit was 99.08 %, n = 9 and the related substances were well separated. This method resulted to be convenient, accurate, selective and reliable, and can be applied for the quality control of folic acid.Colegio de Farmacéuticos de la Provincia de Buenos Aire

    Feature Selection for Genomic Signal Processing: Unsupervised, Supervised, and Self-Supervised Scenarios

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    effective data mining system lies in the representation of pattern vectors. For many bioinformatic applications, data are represented as vectors of extremely high dimension. This motivates the research on feature selection. In the literature, there are plenty of reports on feature selection methods. In terms of training data types, they are divided into the unsupervised and supervised categories. In terms of selection methods, they fall into filter and wrapper categories. This paper will provide a brief overview on the state-of-the-arts feature selection methods on all these categories. Sample applications of these methods for genomic signal processing will be highlighted. This paper also describes a notion of self-supervision. A special method called vector index adaptive SVM (VIA-SVM) is described for selecting features under the self-supervision scenario. Furthermore, the paper makes use of a more powerful symmetric doubly supervised formulation, for which VIA-SVM is particularly useful. Based on several subcellular localization experiments, and microarray time course experiments, the VIA-SVM algorithm when combined with some filter-type metrics appears to deliver a substantial dimension reduction (one-order of magnitude) with only little degradation on accuracy

    Single crystal XRD study of 4,4'-dipyridyl - p-ethoxybenzoic acid and N,N'-dipyridylpiperazine - p-ethoxybenzoic acid co-crystals: Direct evidence of H-bond interaction in the corresponding liquid-crystalline mesogenic phases

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    Supramolecular H-bonded complexes formed between p-ethoxybenzoic acid and 4,4'-dipyridyl or N,N'-dipyridylpiperazine were obtained as nematic liquid-crystalline phases. The corresponding crystals suitable for single crystal X-ray analysis were isolated and investigated. The stoichiomtery of complex 1 is (4,4'-dipyridyl)-2(p-ethoxybenzoic acid) and that of complex 2 is (N,N'-dipyridylpiperazine)-2(p-ethoxybenzoic acid). The molecular packing observed in the crystal structures investigated indicates that the mesogenic phases of the complexes are induced by H-bond interactions

    Preparation and quality evaluation of Ibuprofen and Piphenhydramine hydrochloride orally disintegrating tablets

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    The present study was designed to evaluate the preparation and quality of ibuprofen and diphenhydramine hydrochloride orally disintegrating tablets. The formulation was optimized with disintegration time and taste as reference parameters by single-factor and orthogonal experiments. Then the hardness, disintegrating time and dissolution were examined. The best prescription was found to contain: ibuprofen 200 mg, diphenhydramine HCl 25 mg, citric acid 30 mg, microcrystalline cellulose 115 mg, mannitol 48.5 mg, polyvinylpolypyrrolidone 40 mg, sodium lauryl sulphate 10 mg, magnesium Stearate 3.5 mg, gum arabic 1.5 mg, aspartame 15 mg, steviosin 1.5 mg, and sodium bicarbonate 10 mg. The orally disintegrating tablets were congruent and smooth with pleasant taste in mouth. The disintegration time was less than 60 s, and more than 80 % of ibuprofen and diphenhydramine HCl were dissolved within 10 min. Consequently, the formulation design is reasonable and the process of preparation is feasible.Colegio de Farmacéuticos de la Provincia de Buenos Aire

    Lean Breed Landrace Pigs Harbor Fecal Methanogens at Higher Diversity and Density than Obese Breed Erhualian Pigs

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    The diversity of fecal methanogens of Erhualian (obese type) and Landrace (lean type) pigs was examined using separate 16S rRNA gene libraries for each breed. A total of 763 clones were analyzed; 381 from the Erhualian library and 382 from the Landrace library were identified belonging to the genus Methanobrevibacter. Others were identified belonging to the genus Methanosphaera. The two libraries showed significant differences in diversity (P <0.05) and composition (P <0.0001). Only two operational taxonomic units (OTUs) were found in both libraries, whereas six OTUs were found only in the Erhualian library and 23 OTUs were found only in the Landrace library. Real-time PCR showed that the abundance of fecal methanogens in Landrace pigs was significantly higher than that in Erhualian pigs (P <0.05). Results showed that the Landrace pig (lean) harbored a greater diversity and higher numbers of methanogen mcrA gene copies than the Erhualian pig (obese). These differences may be related to the fatness or leanness in these two pig breeds. The results provide new leads for further investigations on the fat storage of pigs or even humans

    Burden of major gastrointestinal bleeding among oral anticoagulant-treated non-valvular atrial fibrillation patients

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    BackgroundGastrointestinal (GI) bleeding is the most common type of major bleeding associated with oral anticoagulant (OAC) treatment. Patients with major bleeding are at an increased risk of a stroke if an OAC is not reinitiated.MethodsNon-valvular atrial fibrillation (NVAF) patients initiating OACs were identified from the Centers for Medicare and Medicaid Services (CMS) Medicare data and four US commercial claims databases. Patients who had a major GI bleeding event (hospitalization with primary diagnosis of GI bleeding) while on an OAC were selected. A control cohort of patients without a major GI bleed during OAC treatment was matched to major GI bleeding patients using propensity scores. Stroke/systemic embolism (SE), major bleeding, and mortality (in the CMS population) were examined using Cox proportional hazards models with robust sandwich estimates.ResultsA total of 15,888 patients with major GI bleeding and 833,052 patients without major GI bleeding were included in the study. Within 90 days of the major GI bleed, 58% of patients discontinued the initial OAC treatment. Patients with a major GI bleed had a higher risk of stroke/SE [hazard ratio (HR): 1.57, 95% confidence interval (CI): 1.42-1.74], major bleeding (HR: 2.79, 95% CI: 2.64-2.95), and all-cause mortality (HR: 1.29, 95% CI: 1.23-1.36) than patients without a major GI bleed.ConclusionPatients with a major GI bleed on OAC had a high rate of OAC discontinuation and significantly higher risk of stroke/SE, major bleeding, and mortality after hospital discharge than those without. Effective management strategies are needed for patients with risk factors for major GI bleeding

    Respuestas del δ13C foliar y características foliares a la precipitación y temperatura en un ecosistema árido del noroeste de China

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    El δ13C foliar es ampliamente usado para explicar estrategias relacionadas con la disponibilidad de recursos en diferentes ambientes. Sin embargo, la respuesta conjunta del δ13C foliar a la precipitación y temperatura así como la relación entre el δ13C foliar y las características foliares no están claras. El δ13C foliar y su relación con las características foliares [tamaño de hoja (LS), longitud foliar (LL), ancho foliar (LW), relación entre la longitud y el ancho foliar (L:W), área foliar específica (SLA) y concentración de N foliar (en una base de peso seco) (Nmass)] fueron investigadas en la especie de arbusto dominante Nitraria tangutorum Bobr en la región árida (Dengkou y Minqin) del noroeste de China. El estudio se efectuó bajo condiciones de varias cantidades de precipitación simuladas (PGS) y temperaturas ambientales (TGS) en las estaciones de crecimiento de 2008, 2009 y 2010. Los resultados mostraron que LS, LW, LL, SLA y Nmass se incrementaron significativamente cuando las cantidades de PGS se incrementaron, pero hubo tendencias de reducción en dichas características cuando las TGS aumentaron. Sin embargo, la mayoría de las relaciones negativas entre las características foliares y las TGS no fueron obvias en Minqin. En ambos sitios, L:W se incrementó cuando las PGS y TGS aumentaron. Hubo un cambio en la relación negativa entre el δ13C foliar-PGS a través de Minqin y Dengkou, lo cual condujo a la falta de efectos de la precipitación en el δ13C foliar a través de ambos sitios, y mayor δ13C foliar a menor precipitación en Minqin. A través de Minqin y Dengkou, PGS solo pudo explicar un 14% de la variación en el δ13C foliar. La combinación de PGS y TGS pudo explicar un 64% de la variación en el δ13C foliar. Las características foliares (LW y L:W) mejoraron aún más la estimación del δ13C foliar. Las combinaciones de PGS, TGS, LW y L:W pudieron explicar un 84% de la variación en el δ13C foliar. Nuestro estudio demostró la importancia de las características foliares en explorar las respuestas del δ13C foliar a cambios globales en ecosistemas áridos.Leaf δ13C is widely used to explain plant strategies related to resource availability in different environments. To understand the coupled response of leaf δ13C to precipitation, temperature and the relationship between leaf δ13C and leaf traits in arid ecosystems, the leaf δ13C and leaf traits (leaf size (LS), leaf length (LL), leaf width (LW), leaf length to width ratio (L:W), specific leaf area (SLA) and mass-based leaf nitrogen concentration (Nmass)) of Nitraria tangutorum Bobr. under simulated increasing precipitation (PGS) and ambient temperature (TGS) in plant growing season from 2008 to 2010 and the relationships between leaf δ13C and leaf traits were investigated in the arid region (Dengkou and Minqin) of northwestern China. Our results showed that LS, LW, LL, SLA and Nmass significantly increased with increasing PGS, but had downward tendencies with increasing TGS although the majority of the negative relationships between leaf traits and TGS were not obvious in Minqin. At the two study sites, L:W increased simultaneously with increasing PGS and TGS. There was a shift in the negative leaf δ13C-PGS relationship across Minqin and Dengkou, which conduce to the lacking effect of precipitation on leaf δ13C across the two sites and higher leaf δ13C in lower precipitation fields in Minqin. Across Minqin and Dengkou, PGS could only explain 14% of the variation in leaf δ13C. The combinations of PGS and TGS could explain 64% of the variation in leaf δ13C. Leaf traits (LW and L:W) could be used to further improve the estimation of leaf δ13C. The combinations of PGS, TGS, LW and L:W could explain 84 % of the variation in leaf δ13C. Our study demonstrated the importance of leaf traits in exploring the responses of leaf δ13C to global changes in arid ecosystems.Fil: Xin, Z.M.. Chinese Academy of Forestry. Institute of Desertification Studies; China. Chinese Academy of Forestry. Experimental Center of Desert Forestry; ChinaFil: Liu, M.H.. Chinese Academy of Forestry. Experimental Center of Desert Forestry; ChinaFil: Lu, Q.. Chinese Academy of Forestry. Institute of Desertification Studies; China. State Forestry Administration. Kumtag Desert Ecosystem Research Station; ChinaFil: Busso, Carlos Alberto. Universidad Nacional del Sur. Departamento de Agronomía; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. State Forestry Administration. Kumtag Desert Ecosystem Research Station; ChinaFil: Zhu, Y.J.. State Forestry Administration. Kumtag Desert Ecosystem Research Station; China. Chinese Academy of Forestry. Institute of Desertification Studies; ChinaFil: Li, Z.. Chinese Academy of Forestry. Experimental Center of Desert Forestry; ChinaFil: Huang, Y.R.. Chinese Academy of Forestry. Experimental Center of Desert Forestry; ChinaFil: Li, X.L.. Chinese Academy of Forestry. Experimental Center of Desert Forestry; ChinaFil: Luo, F.M.. Chinese Academy of Forestry. Experimental Center of Desert Forestry; ChinaFil: Bao, F.. Chinese Academy of Forestry. Institute of Desertification Studies; ChinaFil: Qian, J.Q.. Henan Agricultural University. College of Forestry; ChinaFil: Li, Y.H.. Chinese Academy of Forestry. Institute of Desertification Studies; China. State Forestry Administration. Kumtag Desert Ecosystem Research Station; Chin

    Oral Anticoagulants for Nonvalvular Atrial Fibrillation in Patients with High Risk of Gastrointestinal Bleeding

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    IMPORTANCE: Many patients with nonvalvular atrial fibrillation (NVAF) are at a high risk of gastrointestinal (GI) bleeding due to conditions including older age; stage III to V chronic kidney disease (CKD); HAS-BLED (hypertension, kidney or liver disease, stroke history, prior bleeding, unstable international normalized ratio, age >65, drug or alcohol use) score of 3 or greater; corticosteroid, antiplatelet or nonsteroidal anti-inflammatory drug (NSAID) use; or GI conditions. OBJECTIVE: To compare the risk of stroke and/or systemic embolism (SE) and major bleeding (MB) among patients with NVAF and high risk of GI bleeding who received non–vitamin K antagonist oral anticoagulants (NOACs) vs those who received warfarin. DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study included patients with NVAF who were 75 years and older; had stage III to V CKD; had an HAS-BLED score of 3 or greater; used corticosteroids, antiplatelets, or NSAIDs; or had GI conditions. Data were collected from the Centers for Medicare & Medicaid Services and 4 commercial insurance databases between January 1, 2012, and September 30, 2015. Data analysis was conducted from January 2012 to September 2015. EXPOSURES: New prescription for apixaban, dabigatran, rivaroxaban, or warfarin between January 1, 2013, and September 30, 2015 (identification period). MAIN OUTCOMES AND MEASURES: Six propensity score–matched cohorts were created to compare between study drugs. For the primary objective, Cox models were used to estimate stroke and/or SE and MB hazard ratios (HRs). RESULTS: A total of 381 054 patients (187 489 [49.2%] women) with NVAF and at least 1 high-risk GI bleeding factor were identified (HAS-BLED score ≥3: 284 527 [74.7%]; aged ≥75 years: 252 835 [66.4%]; corticosteroid, antiplatelet, or NSAID therapy: 107 675 [28.3%]; prior GI bleeding conditions: 74 818 [19.6%]; and stage III-V CKD: 56 892 [14.9%]). All NOACs were associated with a lower risk of stroke and/or SE vs warfarin (apixaban: HR, 0.60; 95% CI, 0.52-0.68; dabigatran: HR, 0.75; 95% CI, 0.64-0.88; rivaroxaban: HR, 0.79; 95% CI, 0.73-0.86). Compared with warfarin, apixaban and dabigatran were associated with a lower risk of MB (apixaban: HR, 0.59; 95% CI, 0.56-0.63; dabigatran: HR, 0.78; 95% CI, 0.70-0.86), while rivaroxaban was associated with a higher risk (HR, 1.11; 95% CI, 1.05-1.16). CONCLUSIONS AND RELEVANCE: In this study of patients with NVAF and high risk of GI bleed, NOACs were associated with lower rates of stroke and/or SE, but NOACs had varying risks of MB compared with warfarin. These results may help inform treatment options in this patient population

    Density functional study of Aun_n (n=2-20) clusters: lowest-energy structures and electronic properties

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    We have investigated the lowest-energy structures and electronic properties of the Aun_n(n=2-20) clusters based on density functional theory (DFT) with local density approximation. The small Aun_n clusters adopt planar structures up to n=6. Tabular cage structures are preferred in the range of n=10-14 and a structural transition from tabular cage-like structure to compact near-spherical structure is found around n=15. The most stable configurations obtained for Au13_{13} and Au19_{19} clusters are amorphous instead of icosahedral or fcc-like, while the electronic density of states sensitively depend on the cluster geometry. Dramatic odd-even alternative behaviors are obtained in the relative stability, HOMO-LUMO gaps and ionization potentials of gold clusters. The size evolution of electronic properties is discussed and the theoretical ionization potentials of Aun_n clusters compare well with experiments.Comment: 6 pages, 7 figure
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