7,051 research outputs found
Fast evaluation of scaled opposite spin second-order Moller-Plesset correlation energies using auxiliary basis expansions and exploiting sparsity
No full textThe scaled opposite spin Moller-Plesset method (SOS-MP2) is an economical way of obtaining correlation energies that are computationally cheaper, and yet, in a statistical sense, of higher quality than standard MP2 theory, by introducing one empirical parameter. But SOS-MP2 still has a fourth-order scaling step that makes the method inapplicable to very large molecular systems. We reduce the scaling of SOS-MP2 by exploiting the sparsity of expansion coefficients and local integral matrices, by performing local auxiliary basis expansions for the occupied-virtual product distributions. To exploit sparsity of 3-index local quantities, we use a blocking scheme in which entire zero-rows and columns, for a given third global index, are deleted by comparison against a numerical threshold. This approach minimizes sparse matrix book-keeping overhead, and also provides sufficiently large submatrices after blocking, to allow efficient matrix-matrix multiplies. The resulting algorithm is formally cubic scaling, and requires only moderate computational resources (quadratic memory and disk space) and, in favorable cases, is shown to yield effective quadratic scaling behavior in the size regime we can apply it to. Errors associated with local fitting using the attenuated Coulomb metric and numerical thresholds in the blocking procedure are found to be insignificant in terms of the predicted relative energies. A diverse set of test calculations shows that the size of system where significant computational savings can be achieved depends strongly on the dimensionality of the system, and the extent of localizability of the molecular orbitals. (c) 2007 Wiley Periodicals, Inc
Prevalence of self-reported work-related skin conditions in Taiwanese working population.
No full textHIGH RESOLUTION FOURIER TRANSFORM EMISSION SPECTROSCOPY OF YH AND YD.
No full textAuthor Institution: Department of Chemistry, University of Arizona; Department of Chemistry, University of WaterlooThe electronic emission spectrum of YH and YD has been investigated in the 690 nm to 3 spectral region using a Fourier transform spectrometer. The YH and YD bands were excited in an yttrium hollow cathode lamp operated with neon gas and a trace of of The observed bands have been classified into three different electronic transitions; and . The transition of YD could not be identified due to its very weak intensity. The rotational analysis of several bands of the transition (up to for YH and for YD) provides improved equilibrium vibrational and rotational constants for the ground state of YH and YD. The excited state is involved in several perturbations
Charge-transfer reactions at liquid/liquid interfaces and their applications in bioassays
No full textThe diversity of charge-transfer reactions (CRTs) is one of the characteristics of the electrochemistry of liquid/liquid interfaces. CRTs can be classified in to ion-transfer (IT) reactions, facilitated ion-transfer (FIT) reactions, and electron-transfer (ET) reactions. Most of the IT and Fit can be employed to design amperometric ion sensors as they are reversible and the currents resulting from them are proportional to the concentration of the related species. CRTs are widely used in bioassays such as detection of biologically interesting molecules, and biosensing of glucose.Biochemical Research MethodsChemistry, AnalyticalSCI(E)EIPubMed0EDITORIAL MATERIAL3428-43238
Involvement of adrenoceptors, dopamine receptors and AMPA receptors in antidepressant-like action of 7-O-ethylfangchinoline in mice
No full textAim: 7-O-ethylfangchinoline (YH-200) is a bisbenzylisoquinoline derivative. The aim of this study was to investigate the antidepressant-like action and underlying mechanisms of YH-200 in mice. Methods: Mice were treated with YH-200 (15, 30, and 60 mg/kg, ig) or tetrandrine (30 and 60 mg/kg, ig) before conducting forced swimming test (FST), tail suspension test (TST), or open field test (OFT). Results: YH-200 (60 mg/kg) significantly decreased the immobility time in both FST and TST, and prolonged the latency to immobility in FST. YH-200 (60 mg/kg) was more potent than the natural bisbenzylisoquinoline alkaloid tetrandrine (60 mg/kg) in FST. Pretreatment with alpha(1)-adrenoceptor antagonist prazosin (1 mg/kg), beta-adrenoceptor antagonist propranolol (2 mg/kg), dopamine D-1/D-5 receptor antagonist SCH23390 (0.05 mg/kg), dopamine D-2/D-3 receptor antagonist haloperidol (0.2 mg/kg) or AMPA receptor antagonist NBQX (10 mg/kg) prevented the antidepressant-like action of YH-200 (60 mg/kg) in FST. In contrast, pretreatment with alpha(2) adrenoceptor antagonist yohimbine (1 mg/kg) augmented the antidepressant-like action of YH-200 (30 mg/kg) in FST. Chronic administration of YH-200 (30 and 60 mg/kg for 14 d) did not produce drug tolerance; instead its antidepressant-like action was strengthened. Chronic administration of YH-200 did not affect the body weight of mice compared to control mice. Conclusion: YH-200 exerts its antidepressant-like action in mice via acting at multi-targets, including alpha(1), alpha(2) and beta-adrenoceptors, D-1/D-5 and D-2 /D-3 receptors, as well as AMPA receptors.National Natural Science Foundation of China [81173031, 81202511, 81302746]SCI(E)PubMed中国科技核心期刊(ISTIC)中国科学引文数据库(CSCD)[email protected]
La doped SrTiO3 thin films on SrLaAlO4 (001) as transparent conductor
No full textTransparent conductors are essential for many optoelectronic applications, and economically viable replacement for the industry standard transparent conductor, indium tin oxide, is in dire need. Electronic structure calculations are performed to confirm that La doping in a band insulator SrTiO3 provides carriers in the conduction band without generating in-gap states and thus La doped SrTiO3 would retain good optical transparency. To realize the computational results, we synthesize La doped SrTiO3 in thin film form and characterize the films. It is demonstrated that 10% La doped SrTiO3 thin films on SrLaAlO4 (001) substrates are indeed transparent conductors with sheet resistance R-S similar to 60 Omega/square and 80% transmission in the visible wavelength range at room temperature. (C) 2013 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License.open1145sciescopu
Responses of soil microbial communities to prescribed burning in two paired vegetation sites in southern China
No full textReverse nearest neighbors Bhattacharyya bound linear discriminant analysis for multimodal classification
No full textRecently, an effective improvement of linear discriminant analysis (LDA) called L2-norm linear discriminant analysis via the Bhattacharyya error bound estimation (L2BLDA) was proposed in its adaptability and nonsingularity. However, L2BLDA assumes all samples from the same class are independently identically distributed (i.i.d.). In real world, this assumption sometimes fails. To solve this problem, in this paper, reverse nearest neighbor (RNN) technique is imbedded into L2BLDA and a novel linear discriminant analysis named RNNL2BLDA is proposed. Rather than using classes to construct within-class and between-class scatters, RNNL2BLDA divides each class into subclasses by using RNN technique, and then defines the scatter matrices on these classes that may contain several subclasses. This makes RNNL2BLDA get rid of the i.i.d.assumption in L2BLDA and applicable to multimodal data, which have mixture of Gaussian distributions. In addition, by setting a threshold in RNN, RNNL2BLDA achieves robustness. RNNL2BLDA can be solved through a simple standard generalized eigenvalue problem. Experimental results on an artificial data set, some benchmark data sets as well as two human face databases demonstrate the effectiveness of the proposed method.No Full Tex
The safety and efficacy of aspirin intake in photoselective vaporization laser treatment of benign prostate hyperplasia
No full textCorrigendumShao IH, Hou CP, Chen SM, Chen CL, Lin YH, Chang PL, Tsui KH. The safety and efficacy of aspirin intake in photoselective vaporization laser treatment of benign prostate hyperplasia. Clinical Interventions in Aging. 2013, 8:265–269.The authors’ affiliations are incorrectly noted as being in Taiwan, People’s Republic of China. It should be Taiwan, Republic of China.Read the original articl
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