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Open Journal of Anesthesiology 2014年第2期4卷 31-35页

作者： Piacherski valery Marachkou Aliaksei Health Care Institution Mogilev Regional Hospital Mogilev The Republic of Belarus

Aim: To study the features of local anesthetic solution spreading during sciatic nerve block in dependence on the anesthetic solution volume. Material and Methods: One hundred and sixty nine cases of sciatic nerve blocks done under ultrasonic visualization control were analyzed. Sciatic nerve blocks were performed by lidocaine in volumes 30;25;20;15;12.5;10;7.5;6.5;5;4.5 ml. The cross-section area, equal to local anesthetic spreading, was determined;the extension of the anesthetic solution spreading along sciatic nerve was calculated. Results: The anesthetic agent solution spreads along sciatic nerve in proximal and distal direction, forming a kind of cylinder. The minimum volume of the local anesthetic, which covers sciatic nerve in the whole, is 5 ml. A rare (1.77%) variation of sciatic nerve structure was described, in which tibial and common peroneal nerves develop directly from the branches of sacral plexus. Conclusion: The decrease of the local anesthetic volume leads to reduction of its spreading distance and cross-section area. Ultrasonic visualization can provide for sciatic nerve anatomical peculiarities, which can have an effect on the block quality.

关键词： Sciatic Nerve Block Ultrasound-Guided Local Anesthetic Spreading

Development of sorghum mutants with improved in vitro protein digestibility by CRISPR/Cas9 editing of kafirin genes

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作物学报:英文版 2023年第5期11卷 1411-1418页

作者： Lev A.Elkonin Grigoriy A.Gerashchenkov Natalie V.Borisenko Odyssey A.Kenzhegulov Saule Kh.Sarsenova Natalya A.Rozhnova valery M.Panin Federal Centre of Agriculture Research of South-East Region Saratov 410010Russia Institute of Biochemistry and Genetics-Subdivision of the Ufa Federal Research Centre of the Russian Academy of Sciences Ufa 450054Russia

Sorghum(Sorghum bicolor(L.) Moench) is a major world crop that is a reliable source of fodder and food grain in arid regions. However, unlike other cereals, sorghum grain has low nutritional value, owing mainly to the resistance of its storage proteins(kafirins) to protease digestion. Changing the composition of kafirins or their primary structure may address this problem. To induce mutations in kafirin-encoding genes that were expected to disturb their accumulation in endosperm cells, we used a genome-editing approach. By Agrobacterium-mediated genetic transformation of immature embryos of cv. Avans, we obtained 14 transgenic plants with genetic constructs for site-directed mutagenesis of the k1C5 and g KAF1 genes encoding 22 k Da a-and 28 kDa γ-kafirins, respectively. Sequencing of 5 regenerants obtained by using k1C5-addressing vector revealed two plants with mutations. T_1 progeny of these mutants had higher in vitro digestibility of endosperm proteins(86%–92%), in comparison with the donor Avans(63%–67%). The kernels of these plants had a thick vitreous endosperm. A mutant with increased in vitro protein digestibility and vitreous endosperm, carrying a mutation in the target sequence, was also obtained by use of the gKAF1-addressing vector. Thus, using genome editing technology, we have obtained mutants with improved kafirin digestibility that can be used in sorghum breeding.

关键词： Sorghum CRISPR/Cas Kafirins In vitro protein digestibility Vitreous endosperm

Frequency Analysis of Drill Bit Whirlings on Uneven Bottoms of Deep Bore-holes

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Journal of Mathematics and System Science 2017年第1期7卷 14-24页

作者： valery Gulyayev Sergiy Glazunov Olena Vashchilina Department of Mathematics National Transport University Kyiv 01010 Ukraine

An incipient stage of a rotating drill string bit whirl motion proceeding on a well bottom surface is studied on the basis of kinematic （nonholonomic） models of mechanic interaction between the contacting uneven bodies. The bit is considered to be an absolutely rigid spherical or ellipsoidal body, the well bottom surface can be plane or spherical. It is assumed that the system coaxiality is disturbed through small initial curvature of the drill string, imperfections of the bit and bore-well geometry or the system mass debalance. Linearized equations of the bit whirling are deducted, the frequencies of periodic motions are calculated, and their modes are constructed for different geometric parameters of the spherical and ellipsoidal bits. It is demonstrated that, depending on the system properties, the bit motion can acquire the regimes of forward and backward whMings or to transit to the state of stationary spinning relative to an immovable center of velocities. The most unfavorable and atypical whirling modes are characteristic for oblate eilipsoidal bits and curvilinear surfaces of the well bottom.

关键词： Deep drilling spherical and ellipsoidal bits nonholonomic dynamics forward and backward whirls

Obtaining Bacteriocins by Chromatographic Methods

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Advances in Bioscience and Biotechnology 2014年第5期5卷 446-451页

作者： valery Borzenkov Vladimir Surovtsev Ivan Dyatlov Department of Diagnostic Preparations State Research Center for Applied Microbiology and Biotechnology Serpukhov Russia Department of Diagnostic Preparations State Research Center for Applied Microbiology and Biotechnology Serpukhov Russia Department of Molecular Microbiology State Research Center for Applied Microbiology and Biotechnology Serpukhov Russia Department of Molecular Microbiology State Research Center for Applied Microbiology and Biotechnology Serpukhov Russia

Bacteriocins are a large group of chromosome or plasmid-encoded and ribosomally synthesized low-molecular-weight (2 to 6 kDa) antimicrobial and amphiphilous peptides produced by Gr+ or Gr- bacteria [1]. Their low toxicity as well as the absence of allergenicity and reactogenicity is confirmed by testing selected bacteriocins [2] [3]. Bacteriocins can be widely used as preservatives and antibiotic alternatives in medicine. Nisin, a Streptococcus lactis-derived bacteriocin, has been in practice in food industry for a long time. A relevant product contains about 2.5% of nisin. For medical use (e.g., when injected into the blood stream), highly purified drugs are required. However, the yield of bacteriocins accounts for no more than a few percents from the total activity in the culture liquid. In this paper, we propose methods (by example of two B. subtilis strains), allowing to increase the yield up to ~80%. It is believed that other bacteriocins may be purified by these methods and with the same yield.

关键词： Purification Bacteriocins Surface Cell Fragments Hydrophobicity Membranes Ion-Exchange Hydrophobic Chromatography

Compact Electric Energy Storage for Marine Vehicles Using on-Board Hydrogen Production

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Journal of Shipping and Ocean Engineering 2015年第4期5卷 151-158页

作者： Alon Gany Shani Elitzur valery Rosenband Faculty of Aerospace Engineering Teehnion-lsrael Institute of Technology Haifa 3200003 Israel

The use of electric energy in marine vessels has been increasing in recent years. In general, it is motivated by the low ecological impact. However, in the case of underwater vehicles it is functionally essential. The objective of this study is to demonstrate the advantage of electric power generation and storage based on on-board hydrogen generation via the reaction between activated aluminum and water and application of the hydrogen in a fuel cell. The original activation process enabling a spontaneous reaction with water to produce hydrogen as well as a parametric study of hydrogen generation rate and yield are briefly described. The potential increase in specific energy （energy per unit mass） and energy density （energy per unit volume） vs. batteries and other means of hydrogen storage is presented. It is shown that the use of the present technology may result in a substantial increase of specific electric energy along with a reduction in volume or an increase in operating time for the same overall mass of energy storage and generation system.

关键词： Hydrogen production aluminum-water reaction activated aluminum fuel cell energy storage marine electric power.

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大模型来了,你要裁员吗

Stationary and Non-stationary Self-Induced Vibrations in Waveguiding Systems

商业评论 2024年第5期 174-182页

作者：彼得·卡佩利普拉桑纳·塔姆比瓦莱丽·雅库博维奇徐广彤宾夕法尼亚大学沃顿商学院沃顿商学院沃顿商学院麦克创新管理研究所

大语言模型(Large Language Model,LLM)是在数据科学领域带来范式变革的一项创新.它拓展了机器学习模型的能力,可以根据各种定性提示词生成相关文本和图像.这类工具价格昂贵且开发难度高,但是大量用户可以既快又便宜地用其执行某些基于...

大语言模型(Large Language Model,LLM)是在数据科学领域带来范式变革的一项创新.它拓展了机器学习模型的能力,可以根据各种定性提示词生成相关文本和图像.这类工具价格昂贵且开发难度高,但是大量用户可以既快又便宜地用其执行某些基于语言的任务,而这些任务以往必须由人工完成.

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Journal of Mechanics Engineering and Automation 2014年第3期4卷 213-224页

作者： valery Gulyayev Olga Glushakova Sergey Glazunov The Department of Mathematics National Transport University Kiev 01010 Ukraine

With the use of a wave model, the non-linear problem about realization of the Poincare-Hopf bifurcations in waveguiding systems is stated. The constitutive non-linear differential equations are deduced, the methods for their solution are elaborated. The example of torsion wave propagation in an elongated drill string is considered. Computer simulation of auto-oscillation generation in the examined system is performed for the cases of stationary and non-stationary variations of the perturbation parameter. The diapason of the drilling rotation velocity values corresponding to regimes of stable self-excited periodic motions of the system is found. This domain is shown to be limited by the states of the Poincare-Hopf bifurcations. Owing to the feature that the stated problem is singularly perturbed, the autovibrations are of relaxation type with fast and slow motions. Influence of the length of the uniform and articulated drill strings on the bifurcation values of their angular velocities of generation and accomplishment of the auto-oscillation processes in the drill strings is discussed.

关键词： Waveguiding systems singularly perturbed problem self-induced vibrations Hopf's bifurcation relaxation vibrations.

Polynomial Quasisolutions Method for Some Linear Differential Difference Equations of Mixed Type

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Journal of Mathematics and System Science 2014年第4期4卷 225-230页

作者： valery Cherepennikov Natalia Gorbatskaia Polina Sorokina Melentiev Energy Systems Institute SB RAS 664033 Irkutsk Russia Irkutsk State University Irkutsk 664001 Russia Baikal National University of Economics and Law Irkutsk 664001 Russia

The paper considers a scalar linear differential difference equation （LDDE） of mixed type x（t） = （a0 ＋ a1t）X（t）＋（b0 ＋ b1t）x（t - 1）＋（d0 ＋ d1tx（t ＋ 1）＋ f（t）, t ∈ R, （＊） where f（t） = ∑... 详细信息

The paper considers a scalar linear differential difference equation （LDDE） of mixed type x（t） = （a0 ＋ a1t）X（t）＋（b0 ＋ b1t）x（t - 1）＋（d0 ＋ d1tx（t ＋ 1）＋ f（t）, t ∈ R, （＊） where f（t） = ∑n=0^F fn^tn. This equation is investigated with the use of the method of polynomial quasisolutions based on the representation of an unknown function in the form of polynomial x（t） = ∑n=0^N xn^tn. As a result of substitution of this function into equation （＊）, there appears a residual △（t） = 0（t^N）, for which an exact analytical representation has been obtained. In turn, this allows one to find the unknown coefficients xn and consequently the polynomial quasisolution x（t）. Several examples are considered.

关键词： Diffrential difference equations initial value problem polynomial quasisolutions

Thermodynamics of Systems： Photopolymers-Low-Molecular Liquids

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Journal of Chemistry and Chemical Engineering 2013年第5期7卷 462-467页

作者： Shpineva M. A Konyukhov valery Yuryevich Mendeleev University of Chemical Technology of Russia Moscow Russia

Photopolymers （printing flexoforms） during their operation interact with solvents and properties and ultimately reduces printing quality. A purpose of the work was to study the photopolymer with low-molecular liquids by two independent methods （chromatography and mathematical model of the process the thermodynamic properties and Flory-Huggins polymer-solvent systems. swell. Swelling changes the elastic thermodynamics of interaction of swelling in solvents）. By using a parameters were determined for

关键词： Flexoform swelling gas chromatography Flory-Huggins criteria thermodynamic properties.

Modeling and Analysis of Pumping Motor Drives in Hardware-in-the-Loop Environment

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Journal of Power and Energy Engineering 2014年第10期2卷 19-27页

作者： valery Vodovozov Levon Gevorkov Zoja Raud Tallinn University of Technology Tallinn Estonia

In the proposed paper, the new experimental results are described obtained from the laboratory stand and the model developed by the authors. A method of acquiring characteristics of a pump motor drive using a hardware-in-the-loop simulation approach is explained. To explore the centrifugal pumps manufactured by ABB, their own control system is used whereas an industrial pump is replaced with the specially designed simulator. To clarify the model topology and parameters, a double-machine assembly was designed and used as universal pump prototype. A library of reference and disturbance signals used in pumping was applied as a modeling tool. In this way, the advantages of mathematical and physical simulations have been combined with optimal interaction of both approaches.

关键词： Centrifugal Pump Electric Drive Modeling Hardware-in-the-Loop Simulation