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Electrical triggering of earthquakes:results of laboratory experiments at spring-block models

Earthquake Science 2017年第4期30卷 167-172页

作者： Victor A.Novikov Vladimir I.Okunev vadim N.Klyuchkin Jing Liu Yuri Ya.Ruzhin Xuhui Shen Joint Institute for High Temperatures of Russian Academy of Sciences MoscowRussia Institute of Earthquake Science China Earthquake AdministrationBeijingChina Pushkov Institute of Terrestrial Magnetism and Radio Wave Propagation TroitskMoscow RegionRussia Institute of Crustal Dynamics China Earthquake AdministrationBeijingChina

Recently published results of field and laboratory experiments on the seismic/acoustic response to injection of direct current （DC） pulses into the Earth crust or stressed rock samples raised a question on a possibility of electrical earthquake triggering. A physical mechanism of the considered phenomenon is not clear yet in view of the very low current density （10-7-10-s A/m^2） generated by the pulsed power systems at the epicenter depth （5-10 km） of local earthquakes occurred just after the current injection. The paper describes results of laboratory ＂earthquake＂ triggering by DC pulses under conditions of a spring-block model simulated the seismogenic fault. It is experimentally shown that the electric triggering of the laboratory ＂earthquake＂（sharp slip of a movable block of the spring-block system） is possible only within a range of subcritical state of the system, when the shear stress between the movable and fixed blocks obtains 0.98-0.99 of its critical value. The threshold of electric triggering action is about 20 A/m^2 that is 7-8 orders of magnitude higher than estimated electric current density for Bishkek test site （Northern Tien Shan, Kirghizia） where the seismic response to the man-made electric action was observed. In this connection, the electric triggering phenomena may be explained by contraction of electric current in the narrow conductive areas of the faults and the corresponding increase in current density or by involving the secondary triggering mechanisms like electromagnetic stimulation of conductive fluid migration into the fault area resulted in decrease in the fault strength properties.

关键词： Earthquake simulation Spring-block model Electric pulse Triggering threshold

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Visible light optical coherence tomography measures retinal oxygen metabolic response to systemic oxygenation

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Light(Science & Applications) 2015年第1期4卷 197-206页

作者： Ji Yi Wenzhong Liu Siyu Chen vadim Backman Nader Sheibani Christine M.Sorenson Amani A.Fawzi Robert A.Linsenmeier Hao F.Zhang Department of Biomedical Engineering Northwestern UniversityEvanstonIL 60208USA McPherson Eye Research Institute University of WisconsinMadisonWI 53705USA Department of Ophthalmology Northwestern UniversityChicago Illinois 60611USA Department of Neurobiology Northwestern UniversityEvanstonIL 60208USA

The lack of capability to quantify oxygen metabolism noninvasively impedes both fundamental investigation and clinical diagnosis of a wide spectrum of diseases including all the major blinding diseases such as age-related macular degeneration,diabetic retinopathy,and *** visible light optical coherence tomography(vis-OCT),we demonstrated accurate and robust measurement of retinal oxygen metabolic rate(rMRO2)noninvasively in rat *** continuously monitored the regulatory response of oxygen consumption to a progressive hypoxic *** found that both oxygen delivery,and rMRO2 increased from the highly regulated retinal circulation(RC)under hypoxia,by 0.2860.08 μL min(^-1)(p,0.001),and 0.2060.04 μL min(^-1)(p,0.001)per 100 mmHg systemic pO2 reduction,*** increased oxygen extraction compensated for the deficient oxygen supply from the poorly regulated choroidal *** from an oxygen diffusion model based on previous oxygen electrode measurements corroborated our in vivo *** believe that vis-OCT has the potential to reveal the fundamental role of oxygen metabolism in various retinal diseases.

关键词： oxygen metabolism retinal circulation visible light optical coherence tomography

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Thz Radiation under Tunneling in Asymmetric Double Quatum Wells

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Journal of Electromagnetic Analysis and Applications 2011年第7期3卷 271-276页

作者： Menberu Mengesha Svetlana Koshvaya vadim Mal’nev 不详

The asymmetric parabolic double quantum wells (DQWs) with resonant levels (the ground state energy in one well co-incides with the first excited state energy in another well) is analyzed. The splitting of these levels and the tunneling times are calculated. If the typical life time of the excited state is much smaller than the tunneling time between wells, the charged particle can radiate as a result of the quantum transition from the excited state to the ground state. In the opposite case, the asymmetric DQWs can be treated as a metastable excited nanosystem regardless of that the dipole transition from the excited state to ground state is permitted. The lifetime of this metastable state can be considerably reduced by putting it into a resonant cavity. The possibility of coherent radiation of an ensemble of asymmetric DQWS is discussed.

关键词： Double Quantum Well Energy Splitting Tunneling Quantum Transitions

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Cervical dystonia associated with cavernous angioma of the frontal lobe

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Case Reports in Clinical Medicine 2013年第4期2卷 239-241页

作者： Belenky vadim Victorovich Voitsitsky Anatolii Nikolaevich Neurology Clinic of Dr. Voitsitsky St. Petersburg Russia Neurology Clinic of Dr. Voitsitsky St. Petersburg Russia

Structural lesions of CNS, reported to be associated with torticollis, are mostly restricted to cerebellum, brain stem and basal ganglia. In fact, we know only about two documented frontal lobe mass lesions—meningiomas, associated with torticollis. Our observation of frontal lobe cavernous angioma associated with clinical picture of torticollis confirms the role this area could play in the pathophysiology of involuntary movements. We report a case of patient with torticollis associated with cavernous angioma of the right frontal lobe and presuppose causative role of angioma in the development of our patient’s torticollis.

关键词： Cervical Dystonia Cavernous Angioma Meningioma

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Segmental closure of the Mongol-Okhotsk Ocean:Insight from detrital geochronology in the East Transbaikalia Basin

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Geoscience Frontiers 2022年第1期13卷 15-27页

作者： Anastasia V.Arzhannikova Elena I.Demonterova Marc Jolivet Ekaterina A.Mikheeva Alexei V.Ivanov Sergey G.Arzhannikov Valentin B.Khubanov vadim S.Kamenetsky Institute of the Earth’s Crust Russian Academy of SciencesSiberian BranchIrkutskRussia Laboratoire Géosciences Rennes CNRS-UMR6118Universitéde RennesRennesFrance Geological Institute Russian Academy of SciencesSiberian BranchUlan-UdeRussia

The Late Paleozoic–Early Mesozoic Mongol-Okhotsk Ocean extended between the Siberian and Amur–North China *** timing and modalities of the oceanic closure are widely *** is largely accepted that the ocean closed in a scissor-like manner from southwest to northeast(in modern coordinates),though the timing of this process remains *** studies have shown that both western(West Transbaikalia)and eastern(Dzhagda)parts of the ocean closed almost simultaneously at the Early–Middle Jurassic ***,little information on the key central part of the oceanic suture zone is *** performed U-Pb(LA-ICP-MS)dating of detrital zircon from wellcharacterized stratigraphic sections of the central part of the Mongol-Okhotsk suture *** include the initial marine and final continental sequences of the East Transbaikalia Basin,deposited on the northern Argun-Idemeg terrane *** provide new stratigraphic ages for the marine and continental *** revised chronostratigraphy allows assigning an age of~165–155 Ma,to the collisionrelated flexure of the northern Argun-Idemeg terrane and the development of a peripheral foreland *** collisional process took place 5 to10 million years later than in the western and eastern parts of the *** demonstrate that the northern Argun-Idemeg terrane was the last block to collide with the Siberian continent,challenging the widely supported scissor-like model of closure of the MongolOkhotsk *** segments of the ocean closed independently,depending on the initial shape of the paleo continental margins.

关键词： Detrital zircon U-Pb geochronology Mongol-Okhotsk collision East Transbaikalian Basin

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<i>CMB</i>—A Geometric, Lorentz Invariant Model in Non-Expanding Lobachevskian Universe with a Black Body Spectral Distribution Function

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Journal of Modern Physics 2017年第13期8卷 2104-2121页

作者： J. Georg von Brzeski vadim von Brzeski Helios Labs Gilroy CA USA

In the present paper, based on Lobachevskian (hyperbolic) static geometry, we present (as an alternative to the existing Big Bang model of CMB) a geometric model of CMB in a Lobachevskian static universe as a homogeneous space of horospheres. It is shown that from the point of view of physics, a horosphere is an electromagnetic wavefront in Lobachevskian space. The presented model of CMB is an Lorentz invariant object, possesses observable properties of isotropy and homogeneity for all observers scattered across the Lobachevskian universe, and has a black body spectrum. The Lorentz invariance of CMB implies a mathematical equation for cosmological redshift for all z. The global picture of CMB, described solely in terms of the Lorentz group—SL(2C), is an infinite union of double sided quotient spaces (double fibration of the Lorentz group) taken over all parabolic stabilizers P⊂SL(2C). The local picture of CMB (as seen by us from Earth) is a Grassmannian space of an infinite union all horospheres containing origin o∈L3, equivalent to a projective plane RP2. The space of electromagnetic wavefronts has a natural identification with the boundary at infinity (an absolute) of Lobachevskian universe. In this way, it is possible to regard the CMB as a reference at infinity (an absolute reference) and consequently to define an absolute motion and absolute rest with respect to CMB, viewed as an infinitely remote reference.

关键词： CMB Cosmological Redshift Non-Expanding Universe Hyperbolic Geometry Horospherical Electromagnetic Waves Hubble’s Error

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Investigation of the Effect of Ambient Temperature and Geomagnetic Activity on the Vascular Parameters of Healthy Volunteers

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Open Journal of Biophysics 2012年第2期2卷 46-55页

作者： Yury Gurfinkel Tamara Breus Tatyana Zenchenko vadim Ozheredov Establishment of the Russian Academy of Sciences Space Research Institute (IKI RAS) Moscow Russia

Aim of this paper is to reveal whether the geomagnetic activity (GMA) and meteorological factors (MFs) affect vascular parameters of healthy volunteers. As a trial study we used new device “Tonocard,” and new vascular parameters for study—a pulse wave velocity (PWV) and an endothelial function (EnF) in addition to blood pressure measurements. These parameters never investigated before in such aspects. As far as novelty of device itself and investigated parameters we limited ourselves by monitoring only four healthy volunteers (without cardiovascular pathology). To analyze the sensitivity of their aforementioned medical indices to GMA and MFs two independent mathematical approaches were used, one of whom is based on traditional methods of mathematical statistics and the other on the theory of pattern recognition Dependence of physiological characteristics on the atmospheric temperature, revealed by both applied mathematical approaches, showed complex non-linear character of biological replies: the reaction has a different form in different temperature ranges and is manifested in the form of synchronization of slow variations of physiological and atmospheric parameters (trends) with a period of several days, while the daily variations were virtually independent. The systolic blood pressure (SBP), PWV and a difference between two specially selected values of PWV (DPWV) are approximately equally depending on atmospheric temperature, which accounts for an average of 26% to 28% of their variations. Sensitivity to the GMA for this test was found only for PWV.

关键词： Vascular Parameters Geomagnetic Disturbances Meteorological Factors

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Ultrathin-shell epitaxial Ag@Au core-shell nanowires for high-performance and chemically-stable electronic, optical, and mechanical devices

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Nano Research 2021年第11期14卷 4294-4303页

作者： Yangzhi Zhu Sanggon Kim Xuezhi Ma Peter Byrley Ning Yu Qiushi Liu Xiaoming Sun Da Xu Sangshan Peng Martin C.Hartel Shiming Zhang vadim Jucaud Mehmet R.Dokmeci Ali Khademhosseini Ruoxue Yan Department of Chemical and Environmental Engineering Bourns College of EngineeringUniversity of California-RiversideRiversideCA92521USA Terasaki Institute for Biomedical Innovation Los AngelesCA90064USA Department of Electrical and Computer Engineering University of California-RiversideRiversideCA92521USA State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029China State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha410082China Department of Bioengineering University of California-Los AngelesLos AngelesCA90095USA Department of Electrical and Electronic Engineering The University of Hong KongHong KongChina Material Science and Engineering Program University of California-RiversideRiversideCA92521USA

Silver nanowires (AgNWs) hold great promise for applications in wearable electronics, flexible solar cells, chemical and biological sensors, photonic/plasmonic circuits, and scanning probe microscopy (SPM) due to their unique plasmonic, mechanical, and electronic properties. However, the lifetime, reliability, and operating conditions of AgNW-based devices are significantly restricted by their poor chemical stability, limiting their commercial potentials. Therefore, it is crucial to create a reliable oxidation barrier on AgNWs that provides long-term chemical stability to various optical, electrical, and mechanical devices while maintaining their high performance. Here we report a room-temperature solution-phase approach to grow an ultra-thin, epitaxial gold coating on AgNWs to effectively shield the Ag surface from environmental oxidation. The Ag@Au core-shell nanowires (Ag@Au NWs) remain stable in air for over six months, under elevated temperature and humidity (80 °C and 100% humidity) for twelve weeks, in physiological buffer solutions for three weeks, and can survive overnight treatment of an oxidative solution (2% H2O2). The Ag@Au core-shell NWs demonstrated comparable performance as pristine AgNWs in various electronic, optical, and mechanical devices, such as transparent mesh electrodes, surface-enhanced Raman spectroscopy (SERS) substrates, plasmonic waveguides, plasmonic nanofocusing probes, and high-aspect-ratio, high-resolution atomic force microscopy (AFM) probes. These Au@Ag core-shell NWs offer a universal solution towards chemically-stable AgNW-based devices without compromising material property or device performance.

关键词： epitaxial growth core-shell nanowire plasmonic waveguides atomic force microscopy(AFM)probe transparent electrode wearable electronics

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Biochemical mechanisms implemented by human acute myeloid leukemia cells to suppress host immune surveillance

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Cellular & Molecular Immunology 2018年第11期15卷 989-991页

作者： Inna M.Yasinska Isabel Gonçalves Silva Svetlana Sakhnevych Bernhard F.Gibbs Ulrike Raap Elizaveta Fasler-Kan vadim V.Sumbayev Medway School of Pharmacy Universities of Kent and GreenwichChatham MaritimeUK Department of Dermatology and Allergy University of OldenburgOldenburgGermany Department of Pediatric Surgery and Department of Biomedical Research Children’s HospitalInselspitalUniversity of BernBernSwitzerland Department of Biomedicine University Hospital Basel and University of Basel BaselSwitzerland

Acute myeloid leukaemia(AML)is a blood/bone marrow cancer originating from myeloid cell precusors capable of *** cells implement biochemical mechanisms which allow them not only to survive,but also to successfully escape immune *** this work,we discuss crucial molecular mechanisms used by human AML cells in order to evade immune attack.

关键词： Acute myeloid leukaemia Immune surveillance Tim-3 galectin-9

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Improvement of Forage Production Sustainability in the Leningrad Region under Climate Change

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Journal of Agricultural Science and Technology(A) 2013年第10期3卷 797-802页

作者： Vladimir Surovtsev vadim Molodkin Yulia Nikulina Mikhail Ponomarev Department of Development of Agricultural Sectors North-West Research Institute of Agricultural Economics and OrganizationShosse Podbelskogo Pushkin Saint-Petersburg 196608 Russia Department of Development Biotroph Company Ltd. Pushkin Saint-Petersburg 196602 Russia

The increase of probability and depth of weather anomalies, which is important characteristic of climate change process, leads to higher risk of loss of perennial grasses forage yield, rise of price volatility on forage grain market. Increase of sustainability of dairy production supposes development of adapted to new weather conditions technologies of forage production, which are characterized by different investment and current costs. It generates a need of economic evaluation and comparative analysis of technologies taking into account climate change forecast and need of sustainable forage production guarantee. Purpose of the research project is the development of approaches to assessing adaptive technologies in forage production, increasing of dairy farming sustainability to changes in the external environment, including climate change. We assessed changes in forage production technologies in the Leningrad region of Russia, analyzed the implications of these changes for production and financial performance of dairy farming, proposed and tested methods for determination of the optimum harvesting time of perennial grasses. Special attention is paid to the long-term effects of changing the structure of cows＇ diet--shortening the productive use of animals, which reduces the efficiency of dairy herd use and limits the possibility of expanded reproduction. The primary method of the study is the analysis of milk production statistics in the Leningrad region and the Russian Federation. As a result of the study, the necessity to improve the production and investment planning quality, as well as the use of forecasts during planning of dairy production, is grounded.

关键词： Dairy production forage production climate change adaptation investment efficiency.

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