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81.
82.
Nonlinear Dynamics - The presence of time-varying electromagnetic fields across a neuron cell may cause changes in its electrical characteristics, most notably, in the action potential dynamics.... 相似文献
83.
Two natural extensions of Jensen’s functional equation on the real line are the equations f(xy) + f(xy
up>−1up>) = 2f(x) and f(xy) + f(y
up>−1up>
x) = 2f(x), where f is a map from a multiplicative group G into an abelian additive group H. In a series of papers (see Ng in Aequationes Math 39:85–99, 1990; Ng in Aequationes Math 58:311–320, 1999; Ng in Aequationes Math 62:143–159, 2001), Ng solved these functional equations for the case where G is a free group and the linear group
GLub>nub>(R), R=\mathbbZ,\mathbbR{{GL_n(R), R=\mathbb{Z},\mathbb{R}}} , is a quadratically closed field or a finite field. He also mentioned, without a detailed proof, in the above papers and
in (see Ng in Aequationes Math 70:131–153, 2005) that when G is the symmetric group S
ub>
n
ub>, the group of all solutions of these functional equations coincides with the group of all homomorphisms from (S
ub>
n
ub>, ·) to (H, + ). The aim of this paper is to give an elementary and direct proof of this fact. 相似文献
84.
Comparison of structural,thermodynamic, kinetic and mass transport properties of Mg2+ ion models commonly used in biomolecular simulations 下载免费PDF全文
Maria T. Panteva George M. Giambaşu Darrin M. York 《Journal of computational chemistry》2015,36(13):970-982
The prevalence of Mgup>2+up> ions in biology and their essential role in nucleic acid structure and function has motivated the development of various Mgup>2+up> ion models for use in molecular simulations. Currently, the most widely used models in biomolecular simulations represent a nonbonded metal ion as an ion‐centered point charge surrounded by a nonelectrostatic pairwise potential that takes into account dispersion interactions and exchange effects that give rise to the ion's excluded volume. One strategy toward developing improved models for biomolecular simulations is to first identify a Mgup>2+up> model that is consistent with the simulation force fields that closely reproduces a range of properties in aqueous solution, and then, in a second step, balance the ion–water and ion–solute interactions by tuning parameters in a pairwise fashion where necessary. The present work addresses the first step in which we compare 17 different nonbonded single‐site Mgup>2+up> ion models with respect to their ability to simultaneously reproduce structural, thermodynamic, kinetic and mass transport properties in aqueous solution. None of the models based on a 12‐6 nonelectrostatic nonbonded potential was able to reproduce the experimental radial distribution function, solvation free energy, exchange barrier and diffusion constant. The models based on a 12‐6‐4 potential offered improvement, and one model in particular, in conjunction with the SPC/E water model, performed exceptionally well for all properties. The results reported here establish useful benchmark calculations for Mgup>2+up> ion models that provide insight into the origin of the behavior in aqueous solution, and may aid in the development of next‐generation models that target specific binding sites in biomolecules. © 2015 Wiley Periodicals, Inc. 相似文献
85.
A new computational scheme for solving the bound state configuration-space Faddeev equations is applied. The scheme is based on the spline-approximation and the adiabatic limit of Faddeev equations. An ordering of variables being in agreement with the limit was chosen. As a result the matrix of the eigenvalue problem has a sparse block structure. Calculations of the bound states of µpp, µdd, µtt mesic molecules and ¯pdd, ¯ptt antiprotonic ones, were performed. To check the method, calculations of the binding energies for such systems as the positronium ion Psub>–ub>,up>3up>H andup>3up>He were carried out. The results are compared with the best results of other authors. 相似文献
86.
Molecular characterization and first report of Cryptosporidium genotypes in human population in the Slovak Republic 下载免费PDF全文
Antónia Petrincová Alexandra Valenčáková Lenka Luptáková František Ondriska Jana Kalinová Monika Halánová Oľga Danišová Pavol Jarčuška 《Electrophoresis》2015,36(23):2925-2930
In our study, we examined 91 fecal samples from five different groups of people containing HIV patients, hemodialysis patients, kidney transplant recipients, immunocompetent humans without clinical signs, and humans with suspected cryptosporidiosis. The purpose of our study was to determine species and genotype composition of representatives of Cryptosporidium spp. using PCR analysis of small subunit ribosomal RNA gene and 60‐kDa glycoprotein gene and examine their phylogenetic relationship. In HIV‐positive/AIDS‐infected group of patients and in hemodialysis patients, no presence of Cryptosporidium species was detected. In two kidney transplant recipients, we detected species/genotypes Cryptosporidium parvum IIaA13G1T1R1 (KT355488) and Cryptosporidium hominis IaA11G2R8 (KT355489) and in two immunocompetent patients with clinical symptoms, we identified Cryptosporidium muris and C. hominis IbA10G2T1 (KT355490). In the group of healthy immunocompetent individuals without clinical signs, we identified species/genotype C. hominis IbA11G2 (KT355491) in one sample. 相似文献
87.
Erick Gastellu Rafael García Ana M. Herrera Antonio Ramos Godofredo García Mario Robles Jorge A. Rodríguez Yani D. Ramírez Roberto C. Carrillo 《Entropy (Basel, Switzerland)》2022,24(12)
This work presents the theoretical calculation of isotherm diagrams for quaternary alloys of III–V semiconductor compounds with the form IIIub>xub>IIIub>1−xub>Vub>yub>Vub>1−yub>. In particular, the isotherm diagrams for the Alub>xub>Gaub>1−xub>Asub>yub>Sbub>1−yub> quaternary alloy at low temperatures were calculated (500 °C, 450 °C, 400 °C, and 350 °C). The Alub>xub>Gaub>1−xub>Asub>yub>Sbub>1−yub> quaternary alloy was formed from four binary compounds such as GaAs, AlAs, AlSb, and GaSb, all with direct bandgaps. The regular solution approximation was used to find the quaternary isotherm diagrams, represented in four linearly independent equations, which were solved using Parametric Technology Corporation Mathcad 14.0 software for different arsenic and antimony atomic fractions. The results support the possible growth of layers via liquid-phase epitaxy in a range of temperatures from 500 °C to 350 °C, where the crystalline quality could be improved at low temperatures. These semiconductor layers could have applications for optoelectronic devices in photonic communications, thermophotovoltaic systems, and microwave devices with good crystalline quality. 相似文献
88.
Daniela-Mdlina Ciuc Anghel Anne-Marie Ciobanu Claudia Maria Guu Miriana Stan Gheorghe Tudor Daniela Luiza Baconi 《Molecules (Basel, Switzerland)》2022,27(23)
(1) Background: Methadone, along with buprenorphine, is the most commonly used drug for the treatment of opioid dependence. This study aimed to analyze methadone and its major metabolite, 2-ethylidene-1,5-dimethyl-3,3-diphenyl pyrrolidine (EDDP), in the urine and plasma of opiate addicts. The study group consisted of drug users voluntarily admitted to the detoxification center C.E.T.T.T. “St. Stelian” of Bucharest. Secondly, the study aimed to identify whether urine or plasma provides better results for the proposed method. (2) Methods: A GC-MS method, using an internal standard (diphenylamine) in the FULL-SCAN and SIM modes of operation and using the m/z = 72 ion for methadone and the m/z = 277 ion for EDDP, combined with a liquid–liquid extraction procedure was performed. (3) Results: The applied procedure allows the detection and quantification of methadone in both urine and plasma samples. EDDP was identified in patients with higher levels of methadone. Higher levels of methadone were detected in urine than in plasma samples. (4) Conclusions: This procedure can be used in clinical laboratories for the rapid determination of methadone levels in urine rather than in plasma. The procedure can be applied for the monitoring of methadone substitution treatment. 相似文献
89.
90.
Schimmel u. Co. 《Fresenius' Journal of Analytical Chemistry》1923,62(10):415-416
Ohne Zusammenfassung 相似文献