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991.
992.
Boris S. Kerner 《The European Physical Journal B - Condensed Matter and Complex Systems》2016,89(9):199
We have revealed general physical conditions for the maximization of thenetwork throughput at which free flow conditions are ensured, i.e., traffic breakdowncannot occur in the whole traffic or transportation network. A physical measure of thenetwork – network capacity is introduced that characterizes generalfeatures of the network with respect to the maximization of the network throughput. Thenetwork capacity allows us also to make a general proof of the deterioration of trafficsystem occurring when dynamic traffic assignment is performed in a network based on theclassical Wardrop’ user equilibrium (UE) and system optimum (SO) equilibrium. 相似文献
993.
Ganesh Kamath Igor Kurnikov Boris Fain Igor Leontyev Alexey Illarionov Oleg Butin Michael Olevanov Leonid Pereyaslavets 《Journal of computer-aided molecular design》2016,30(11):977-988
We present the performance of blind predictions of water—cyclohexane distribution coefficients for 53 drug-like compounds in the SAMPL5 challenge by three methods currently in use within our group. Two of them utilize QMPFF3 and ARROW, polarizable force-fields of varying complexity, and the third uses the General Amber Force-Field (GAFF). The polarizable FF’s are implemented in an in-house MD package, Arbalest. We find that when we had time to parametrize the functional groups with care (batch 0), the polarizable force-fields outperformed the non-polarizable one. Conversely, on the full set of 53 compounds, GAFF performed better than both QMPFF3 and ARROW. We also describe the torsion-restrain method we used to improve sampling of molecular conformational space and thus the overall accuracy of prediction. The SAMPL5 challenge highlighted several drawbacks of our force-fields, such as our significant systematic over-estimation of hydrophobic interactions, specifically for alkanes and aromatic rings. 相似文献
994.
Capillary electrophoresis and phenylboronic acid solid phase extraction for the determination of S‐adenosylmethionine/S‐adenosylhomocysteine ratio in human urine 下载免费PDF全文
Alexander Vladimirovich Ivanov Edward Danielevich Virus Ksenya Alexandrovna Nikiforova Nicolai Evgenevich Kushlinskii Boris Petrovich Luzyanin Marina Yurievna Maksimova Mikhail Aleksanrovich Piradov Aslan Amirkhanovich Kubatiev 《Electrophoresis》2016,37(20):2663-2669
An approach that allows direct analysis of the ratio of S‐adenosylmethionine (SAM) and S‐adenosylhomocysteine (SAH) by using CE is presented. The analytes were extracted on phenylboronic acid phase and eluted with 100 mmol/L HCl. CE separation of the analytes took place in the transient isotachophoresis mode with addition of NaCl and meglumine to the samples. The sensitivity (S/N = 3) and quantification limit (S/N = 10) of the method were 0.07 and 0.2 μmol/L, respectively, using a silica capillary with 50 μm internal diameter and 30.5 cm total length. The BGE was 0.02 mol/L Tris with 1 mol/L HCOOH (pH 2.2), and the separation voltage was 15–17 kV. Accuracy of SAM and SAH analysis in urine was 96 and 105%, respectively; interday precision for the SAM/SAH ratio was within 6%. The theoretical plate number exceeded a million. Total analysis time was 8.5 min. 相似文献
995.
Boris Pejin Ana Ciric Mladen Horvatovic Tamara Jurca Jasmina Glamoclija Milos Nikolic 《Natural product research》2016,30(16):1839-1843
The antimicrobial activity of five crude extracts of the freshwater bryozoan Pectinatella magnifica (Leidy, 1851) was evaluated in vitro for the first time. P. magnifica acetone extract exhibited the highest antibacterial activity (minimum inhibitory concentrations (MIC) 0.004–0.350 mg/mL and MBC 0.007–0.500 mg/mL), while its methanol extract showed the most promising antifungal activity (MIC 0.03–0.12 mg/mL and MFC 0.06–0.25 mg/mL). Furthermore, at a concentration of 0.25 MIC, the methanol extract reduced biofilm formation of the bacterial strain Pseudomonas aeruginosa PAO1 in a considerable extent (59.14%). FTIR spectra of the most active extracts indicate the presence of carbonyl compounds, long-chain alcohols and/or sterols. According to the experimental data obtained, P. magnifica methanol extract may be considered as a good resource of novel natural products with potent antibiofilm activity against the bacterium well known for its resistance. 相似文献
996.
Boris A. Trofimov Svetlana F. Malysheva Nina K. Gusarova Vladimir A. Kuimov Nataliya A. Belogorlova Boris G. Sukhov 《Tetrahedron letters》2008,49(21):3480-3483
Red phosphorus reacts with 1-(tert-butyl)-4-vinylbenzene in a superbase media (KOH-DMSO, 90-100 °C, 3 h) to give tris[4-(tert-butyl)phenethyl]phosphine oxide in 77% yield. Microwave activation of the reaction affords the phosphine oxide in 82% yield in 6 min. 相似文献
997.
Yosi Kratish Dr. Arseni Kostenko Alexander Kaushansky Dr. Boris Tumanskii Dr. Dmitry Bravo‐Zhivotovskii Prof. Dr. Yitzhak Apeloig 《Angewandte Chemie (International ed. in English)》2018,57(27):8275-8279
The first persistent platinum(I)‐centered radical was generated by homolytic cleavage of a Pt?HgSiR3 bond of a mercury‐substituted platinum(II) complex. The PtI radical was characterized by EPR spectroscopy, chemical trapping experiments, and density functional theory (DFT) calculations. 相似文献
998.
We prove a global algebraic version of the Lie–Tresse theorem which states that the algebra of differential invariants of an algebraic pseudogroup action on a differential equation is generated by a finite number of rational-polynomial differential invariants and invariant derivations. 相似文献
999.
We present a new combinatorial formula for Hall–Littlewood functions associated with the affine root system of type \({{\tilde{A}}}_{n-1}\), i.e., corresponding to the affine Lie algebra \({{\widehat{\mathfrak {sl}}}}_n\). Our formula has the form of a sum over the elements of a basis constructed by Feigin, Jimbo, Loktev, Miwa and Mukhin in the corresponding irreducible representation. Our formula can be viewed as a weighted sum of exponentials of integer points in a certain infinite-dimensional convex polyhedron. We derive a weighted version of Brion’s theorem and then apply it to our polyhedron to prove the formula. 相似文献
1000.
Leonid G. Fel Boris Y. Rubinstein Vadim Ratner 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2016,67(4):107
We consider a coexistence of two axisymmetric liquid bridges LBi and LBm of two immiscible liquids i and m which are immersed in a third liquid (or gas) e and trapped between two smooth solid bodies with axisymmetric surfaces S1, S2 and free contact lines. Evolution of liquid bridges allows two different configurations of LBi and LBm with multiple (five or three) interfaces of non-smooth shape. We formulate a variational problem with volume constraints and present its governing equations supplemented by boundary conditions. We find a universal relationship between curvature of the interfaces and discuss the Neumann triangle relations at the singular curve where all liquids meet together. 相似文献