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Limb Muscle Hemodynamics and Arterial Distensibility Depend on Atmospheric Pressure in Hypertensive Men

Biomedical and Environmental Sciences 2013年第4期26卷 284-294页

作者： vladimir n.melnikov Sergey G.KRIvOSCHEKOv Tamara G.KOMLYAGInA Svetlana Y.RECHKInA nathan S.COnSEDInE Institute of Physiology Siberian Branch of the Russian Academy of Medical SciencesNovosibirsk630117Russia Sanatorium "El'tsovka " NovosibirskRussia Department of Psychological Medicine University of AucklandNew Zealand

Objective To verify whether peripheral blood circulation and arterial wall distensibility are influenced by atmospheric pressure （AtPr） and to examine if their association is dependent on age and/or sex. Methods Associations among natural AtPr levels （on the examination day as well as 1 and 2 days prior）, limb muscle hemodynamics, and distensibility of conduit arteries were retrospectively examined in an observational study of 276 untreated patients with primary moderate hypertension （mean age 56.4 years, 194 men）. Forearm and calf circulations at rest and 3 min after ischemia were measured by v.n.us occlusion plethysmography. Compliance of the brachial and shank arteries was assessed by oscillometry. Results After adjustment for age, degree of hypertension, and season, correlation and multiple resression analyses revealed a season-independent but age-dependent direct correlation between the stiffness of limb arteries and AtPr levels on the examination day in men, but not women. The association weakened with the degree of hypertension, disappeared with age, and was more evident in the arms than in the legs. Conclusion Parameters of arterial wall distensibility in adult hypertensive men are susceptible to AtPr changes within the usually observed limits （730-770 mmHg）. It is proposed that reduction of arterial wall barometric responsiv.n.ss in women and aging men is a likely mechanism underlying their meteosensitivity.

关键词： Atmospheric pressure Arterial stiffness Compliance v.n.us circulation Age-dependence Sex difference Season

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Evaluation of the energy efficiency of rotary percussive drilling using dimensionless energy index

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第5期14卷 1486-1500页

作者： v.n.Oparin v.n.Karpov v.v.Timonin A.I.Konurin Chinakal Institute of Mining Siberian BranchRussian Academy of SciencesKrasnyi Prospect 54Novosibirsk630091Russia

This paper sets forth a geomechanics framework for assessing the energy efficiency of rotary percussive drilling using the energy criterion, which has been proposed by victor Oparin for volumetric destruction of high-stress rocks hav.n. nonuniform physico-mechanical properties. We review the long-term research and development in the specified area of science and technology, including research and development projects implemented at the Institute of Mining, Siberian Branch of the Russian Academy of Sciences. A new modified expression of Oparin’s dimensionless energy criterion of volumetric rock destruction k is introduced. The range of in situ values is determined for the energy criterion of volumetric rock destruction at the optimized energy efficiency of rotary percussive drilling. The temporospatial intervals of geotechnical monitoring are found to control pneumatic drilling energy efficiency at subsoil use objects in Russia. The integrated experimental, theoretical and geotechnical approach to the comprehensive investigation of real-time processes of rock fracture in rotary percussive drilling using the energy concept possesses the necessary geomechanical performance-and-technology potential to create the next level geotechnical monitoring of drilling systems for various purposes, including determination of physico-mechanical properties and the stress-strain analysis of rock mass in full-scale drilling.

关键词： Rotary percussive drilling Geotechnical monitoring Drilling machine Energy criterion Energy efficiency

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Synthesis of MoO_3 by glow discharge in contact with water

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Plasma Science and Technology 2019年第2期21卷 97-104页

作者： A v KHLYUSTOvA n A SIROTKIn A S KRAYEv v A TITOv A v AGAFOnOv Laboratory of Chemistry of Carbohydrate Coordination Compounds and Supermolecular System G.A.Krestov Institute of Solution Chemistry of RAS

An atmospheric pressure glow discharge was ignited between a molybdenum anode and the water surface of a cathode for the synthesis of MoO_3 powders. The action of glow discharge leads to the non-equilibrium evaporation of water, sputtering of the metal anode and formation of molybdenum(vI) oxide, which deposited on the anode. The chemical composition and morphology of the obtained powder were performed by using x-ray diffraction spectroscopy,scanning electron microscopy and Fourier transform infrared spectroscopy. It was found that the synthesized powders are pure α-MoO_3. The possible mechanism of the formation of molybdenum trioxide during glow discharge treatment was described. The photocatalytic performance of MoO_3 was estimated through the degradation of Rhodamine B under dark and Uv irradiation conditions. Orthorhombic MoO_3 exhibited the best photocatalytic activity for the photodegradation of Rhodamine B of 100% under Uv irradiation for 15 min.

关键词： molybdenum oxide glow discharge photocatalytic activity

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First Occurrence of Paragordius varius in Different Species of Acrididae in Irapuato, Guanajuato, Mexico

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Adv.n.es in Entomology 2025年第1期13卷 120-125页

作者： Manuel Dario Salas-Araiza Ilse Alejandra Huerta-Arredondo Rafael Guzmán-Mendoza Itzel Berenice Aguilar-Campos Daniela de Jesús Bustos-Gallaga Miguel Angel Rocha-García David Isaías Rodríguez-vázquez Agronomy Department Life Sciences Division University of Guanajuato Irapuato Mexico

Acridid populations have increased significantly in recent years, causing damage to crops. Hav.n. biocontrol tools is important as it will help reduce the use of insecticides. This study reports the presence of Paragordius varius in grasshoppers for the first time in Irapuato, Guanajuato, Mexico. Samples were taken from the grass around a water pond. A total of 1,225 grasshoppers were dissected to observe the presence of the worm. Sev.n.species of grasshoppers were identified, with the most abundant species being Melanoplus differentialis. The parasitoid Paragordius varius, a nematomorph, parasitized male M. differentialis in greater numbers. This work is the first record of this parasitoid in Mexico and contributes to the knowledge of the biological control of acridids in Mexico.

关键词： Grasshoppers Paragordius varius Parasitism nematomorph Biological Control

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多孔介质中天然气水合物生成的主要影响因素

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天然气工业 2017年第5期37卷 38-45页

作者： Khlebnikov v.n. Antonov S.v. Mishin A.S. 梁萌 Khamidullina I.v. Zobov P.M. Likhacheva n.v Gushchin P.A. 俄罗斯古勃金国立石油天然气大学

目前有关天然气水合物(以下简称水合物)的研究主要集中在物理化学性质考察和开采(分解)方法探索方面。在进行后者的研究过程中,地层渗流过程的物理模拟至关重要,但目前借助于石油开采研究中广泛应用的填砂管等多孔介质对水合物进行动态... 详细信息

目前有关天然气水合物(以下简称水合物)的研究主要集中在物理化学性质考察和开采(分解)方法探索方面。在进行后者的研究过程中,地层渗流过程的物理模拟至关重要,但目前借助于石油开采研究中广泛应用的填砂管等多孔介质对水合物进行动态过程的研究却鲜有报道。为此,利用河砂填砂管在岩心驱替装置上进行了甲烷水合物生成过程的物理模拟,考察了地层温度、甲烷压力及地层模型性质参数等对水合物生成过程的影响。结果表明:(1)利用冰融水作为地层模型的束缚水可显著提升甲烷水合物的生成速率;(2)多孔介质条件下过程驱动力(即实验压力或温度偏离水合物相平衡对应值的程度)对甲烷水合物的生成起着决定性作用;(3)当甲烷压力高于水合物相平衡压力1.4倍以上,或者实验温度低于相平衡温度3℃以下时,甲烷水合物生成诱导期几乎不随温压条件的变化而变化;(4)渗透率、含水饱和度、润湿性等参数对实验中甲烷水合物的生成率不构成明显影响。

关键词：甲烷水合物多孔介质生成过程天然气水合物地层物理模拟影响因素诱导期生成率

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A review of the effects of dietary organic acids fed to swine

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Journal of Animal Science and Biotechnology 2016年第1期7卷 67-77页

作者： Mocherla v A n Suiryanrayna J v Ramana Livestock Research Station Sri Venkateswara Veterinary University

Animal production depends on nutrient utilization and if done there is an accelerated momentum towards growth with a low cost to feed ratio Public concern over the consumption of pork with antibiotic residues of the animals fed with antibiotic growth promoters （AGP） has paved the way to use other additives like herbs and their products, probiotics, prebiotics etc. numerous feed additives are in vogue for achiev.n. this target and one such classical example is the usage of organic acids and their salts. Usage of organic acids was in progress for over four decades. Early weaned piglets are （3-4 weeks age） exposed to stress with a reduced feed intake, little or no weight gain. This post weaning lag period is due to a limited digestive and absorptive capacity due to insufficient production of hydrochloric acid, pancreatic enzymes and sudden changes in feed consistency and intake. Lowering dietary pH by weak organic acids was found to overcome these problems. The main activity of organic acids is associated with a reduction in gastric pH converting the inactive pepsinogen to active pepsin for effective protein hydrolysis. Organic acids are both bacteriostatic and bactericidal. Lactic acid has been reported to reduce gastric pH and delay the multiplication of an enterotoxigenic E. coil These acids are the intermediary products in Kreb＇s cycle and thus act as an energy source prev.n.ing the tissue breakdown resulting from gluconeogenesis and lipolysis. Excretion of supplemental minerals and nitrogen are minimized with organic acids as these form complexes with minerals and aids for their bio-availability. Short chain fatty cids like acetic, propionic and n-butyric acid produced by microbial fermentation of dietary fibre in the large intestines may increase the proliferation of epithelial cells and have stimulatory effects on both endocrine and exocrine pancreatic secretions in pigs. Organic acids also enhances apparent total tract digestibility and improves growth performa

关键词： Chelation Improved productivity Organic acids Pathogen inhibition Protein utility Swine

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Second-Harmonic Response in Magnetic nodal-Line Semimetal Fe_(3)GeTe_(2)

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Chinese Physics Letters 2022年第9期39卷 62-66页

作者： v.D.Esin A.A.Avakyants A.v.Timonina n.n.Kolesnikov E.v.Deviatov Institute of Solid State Physics of the Russian Academy of Sciences ChernogolovkaMoscow District2 Academician Ossipyan Str.142432Russia

We experimentally investigate second-harmonic transverse voltage response to ac electrical current for a magnetic nodal-line semimetal Fe_(3)GeTe_(2)(FGT).For zero magnetic field,the observed second-harmonic voltage behaves as a square of the longitudinal current,as it should be expected for nonlinear Hall *** magnetic field behavior is found to be sophisticated:while the first-harmonic response shows the known anomalous Hall hysteresis in FGT,the second-harmonic Hall voltage is characterized by the pronounced high-field hysteresis and flat(B-independent)region with curves touching at low *** high-field hysteresis strongly depends on the magnetic field sweep rate,so it reflects some slow relaxation *** the lowest rates,it is also accomplished by multiple crossing *** shape of the second-harmonic hysteresis is known for skyrmion spin textures in nonlinear *** skyrmions have been demonstrated for FGT by direct visualization techniques,we can connect the observed high-field relaxation with deformation of the skyrmion ***,the second-harmonic Hall voltage response can be regarded as a tool to detect spin textures in transport experiments.

关键词： harmonic relaxation hysteresis

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Multiscalar B-L extension based on S_(4)flavor symmetry for neutrino masses and mixing

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Chinese Physics C 2021年第4期45卷 181-191页

作者： v.v.vien H.n.Long Institute of Research and Development Duy Tan University182 Nguyen Van LinhDa Nang CityVietnam Department of Physics Tay Nguyen University567 Le DuanBuon Ma ThuotDakLakVietnam Theoretical Particle Physics and Cosmology Research Group Advanced Institute of Materials ScienceTon Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Applied Sciences Ton Due Thang UnivesityHo Chi Minh CityVietnam

A multiscalar and nonrenormalizable B-L extension of the standard model(SM)with S_(4)symmetry which successfully explains the recently observed neutrino oscillation data is *** tiny neutrino masses and their hierarchies are generated via the type-I seesaw *** model reproduces the recent experiments of neutrino mixing angles and Dirac CP violating phase in which the atmospheric angle(θ_(23))and the reactor angle(θ_(13))get the best-fit values while the solar angle(θ_(12))and Dirac CP violating phase(δ)are in 3σrange of the best-fit value for the normal hierarchy(nH).For the inverted hierarchy(IH),θ13 gets the best-ft value andθ_(23)together withδare in the lσrange,whileθ12 is in 3δrange of the best-fit *** effective neutrino masses are pre-dicted to be(m_(ee))=6.81 mev for the nH and(m_(ee))=48.48 mev for the IH,in good agreement with the most re-cent experimental data.

关键词： neutrino mass and mixing extensions of electroweak Higgs sector flavor symmetries

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Uranium Isotope variations(234U/238U and 238U/235U)and Behavior of U-Pb Isotope System in the vershinnoe Sandstone-Type Uranium Deposit,vitim Uranium Ore District,Russia

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Journal of Earth Science 2022年第2期33卷 317-324页

作者： v.n.Golubev I.v.Chernyshev B.T.Kochkin n.n.Tarasov G.v.Ochirova A.v.Chugaev Institute of Geology of Ore Deposits PetrographyMineralogy and GeochemistryRussian Academy of SciencesMoscow 119017Russia

The U-Pb isotope system and uranium isotope composition(235U/238U and 234U/238U)were studied in a number of samples from the vertical section of the uranium ore body at the vershinnoe sandstone-type deposit,vitim uranium ore district,*** parameters were determined to broadly *** of the 234U/238U ratio from the equilibrium value indicate that the uranium ore was not completely conserved during the postore stage,and uranium was determined to continue migrating at the *** of the U-Pb isotope age value and 234U/238U isotope ratio provides an insight into the migrate direction of uranium in the ore *** broad variations(137.377–137.772)in the 238U/235U ratio over the vertical section of the ore body can be explained by the different settings of the samples relative to the ore deposition front and changes in the redox conditions when this front *** fact that theδ238U and K234/238 values are correlated indicates that the transfer of the 234U isotope into the aqueous phase may have been coupled with isotope fractionation in the 238U-235U system during the postformation uranium migration within the orebody.

关键词： sandstone-type uranium deposit U-Pb age uranium isotope composition ore deposit geology

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Physical vapor transport growth and morphology of Bi2Se3 microcrystals

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Particuology 2016年第3期14卷 118-122页

作者： v.v. Atuchin S.v. Borisov T.A. Gavrilova K.A. Kokh n.v. Kuratieva n.v. Pervukhina Laboratory of Optical Materials and Structures Institute of Semiconductor Physics SB RAS Novosibirsk 630090 Russia Functional Electronics Laboratory Tomsk State University Tomsk 634050 Russia Laboratory of Semiconductor and Dielectric Materials Novosibirsk State University Novosibirsk 630090 Russia Laboratory of Crystul Chemistry Institute of Inorganic Chemistry SB RAS Novosibirsk 630090 Russia Laboratory of nanodiagnostics and nanolithography Institute of Semiconductor Physics SB RAS Novosibirsk 630090 Russia Laboratory of Crystal Growth Institute of Geology and Mineralogy SB RAS Novosibirsk 630090 Russia Geology and Mineralogy Department Novosibirsk State University Novosibirsk 630090 Russia Spintronics Laboratory Saint Petersburg State University Saint Petersburg 198504 Russia Laboratory of Research Methods of Composition and Structure of Functional Materials Novosibirsk State University Novosibirsk 630090 Russia

High-quality Bi2Se3 microcrystals were grown by the physical vapor transport （PvT） method without using a foreign transport agent. The microplate crystals grown under the optimal temperature gradient are well faceted and have dimensions up to -200 μm, The growth proceeds by the layer-by-layer mecha- nism with the formation of flat low-growth rate facets. The phase composition of the grown crystals was identified by the X-ray single crystal structure analysis in space group R3m, a = 4.1356（3）, C= 28.634（5）A, Z=3 （R=0.0147）. The most probable twin planes in the tetradymite structure were evaluated by the pseudo translational sublattice merhad.

关键词： Bi2Se3 Physical vapor transport Structure Twin

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