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International Journal of Disaster Risk Science 2018年第4期9卷 555-560页

作者： Adrian v.Gheorghe Alexandru Georgescu olga Bucovetchi Marilena Lazar Cezar Scarlat Department of Engineering Management and Systems Engineering Old Dominion UniversityNorfolkVA 23529USA Romanian Association for Space Technology and Industry(ROMSPACE) 061126 BucharestRomania University Politehnica of Bucharest 060042 BucharestRomania Military Equipment and Technologies Research Agency of the Romanian Ministry of Defense(METRA) 077025 ClinceniIlfov CountyRomania

Space systems have become a key enabler for a wide variety of applications that are vital to the functioning of advanced societies. The trend is one of quantitative and qualitative increase of this dependence, so much so that space systems have been described as a new example of critical infrastructure. This article argues that the existence of critical space infrastructures implies the emergence of a new category of disasters related to disruption risks. We inventory those risks and make policy recommendations for what is, ultimately, a resilience governance issue.

关键词： Complex systems Infrastructure disruption Resilience governance Space infrastructure System interdependencies

The RdDM Pathway Is Required for Basal Heat Tolerance in Arabidopsis

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Molecular Plant 2013年第2期6卷 396-410页

作者： olga v. Popova Huy Q. Dinh Werner Aufsatz Claudia Jonak GMI-Gregor Mendel Institute of Molecular Plant Biology Austrian Academy of Sciences Dr. Bohr-Gasse 3 1030 Vienna Austria

Heat stress affects epigenetic gene silencing in Arabidopsis. To test for a mechanistic involvement of epige-netic regulation in heat-stress responses, we analyzed the heat tolerance of mutants defective in DnA methylation, his-tone modifications, chromatin-remodeling, or siRnA-based silencing pathways. Plants deficient in nRPD2, the common second-largest subunit of RnA polymerases Iv and v, and in the Rpd3-type histone deacetylase HDA6 were hypersensi- tive to heat exposure. Microarray analysis demonstrated that nRPD2 and HDA6 have independent roles in transcriptional reprogramming in response to temperature stress. The misexpression of protein-coding genes in nrpd2 mutants recover-ing from heat correlated with defective epigenetic regulation of adjacent transposon remnants which involved the loss of control of heat-stress-induced read-through transcription. We provide evidence that the transcriptional response to temperature stress, at least partially, relies on the integrity of the RnA-dependent DnA methylation pathway.

关键词： heat stress RnA-directed DnA methylation transposons read-through transcription.

Paleoclimate Study of Mountain Ecosystems by Multiple Group Biological Analysis

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Journal of Mountain Science 2011年第1期8卷 24-36页

作者： Marina SKRYPnIKOvA olga USPEnSKAya olga KHOKHLOvA Dokuchaev Soil Science Institute of Russian Academy of Agricultural Sciences Pyzhevsky Lane7Moscow109017Russia vegetable Institute of Russian Academy of Agricultural Sciences h.500v.VereaRamenskii distMoscow region140153Russia Institute of Physical Chemical and Biological Problems in Soil Science of RASUlitsa Institutskaya2PushchinoMoscow region142290Russia

Methodological problems of climatic reconstruction for different periods of Holocene are discussed on the basis of a multiple group biological analysis on peat-sapropel sediments. The possibility of biological analysis is exemplified by the paleoclimatic reconstruction for Carpathian and Altai Mountain ranges. For the ＂Skolevsky Beskidy＂ national park of Carpaty the paleoclimatic scenarios have been drown up aiming at the more precise definition of climatic conditions for the period of mass mountain slope terracing. The stability of terrace systems of various designs in the current climatic conditions has been assessed. It is shown that during periods of humid climate the terraces, whose designs have been focused on drainage, were built. In periods of dry and warm climate the terrace systems capable of accumulating water were built. Both these types of terrace systems are destroyed in nowadays. Only those terrace systems are stable which were adjusted by their builders to contrast variations of precipitation. For Western Altais the paleoclimatic scenario has been done to forecast the safety of the Bronze Age kurgans （burial earth mounds） with permafrost inside the construction. In the Altay region during the Holocene it has revealed two periods of sharp cooling, the peaks of which occurred in the intervals 4500- 4300 and 2500-2300 years pronounced climatic drying ago, and two periods of 4900-4700 and 130-70 years ago. Depletion of the algae composition in the layer corresponding to the last period of drying climate indicates a very sharp change in the parameters of moisture and turning the lake into a dry swamp. Periods of cold weather may have contributed to the formation of special ritual traditions of the Sakan tribes that require the frozen ground to bury the dead. The later climate fluctuations identified have not affected the safety of permafrost in burial mounds constructed in the v-III cc BC.

关键词： Climatic reconstruction Complex group biological analysis of peat-sapropel sediments Paleopedology Soil evolution Holocene

The development and application of a multiplex short tandem repeat(STR)system for identifying subspecies,individuals and sex in tigers

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Integrative Zoology 2015年第4期10卷 376-388页

作者： Zheng-Ting ZOU olga v.UPHYRKInA Pavel FOMEnKO Shu-Jin LUO College of Life Sciences Peking-Tsinghua Center for Life SciencesPeking UniversityBeijingChina Institute of Biology and Soil Sciences Far Eastern Branch Russian Academy of SciencesVladivostokRussia World Wide Fund for nature–Russia Amur Branch VladivostokRussia Department of Computational Medicine and Bioinformatics University of MichiganAnn ArborMichiganUSA.

Poaching and trans-boundary trafficking of tigers and body parts are threatening the world’s last remaining wild *** of an efficient molecular genetic assay for tracing the origins of confiscated specimens will assist in law enforcement and wildlife forensics for this iconic flagship *** developed a multiplex genotyping system“tigrisPlex”to simultaneously assess 22 short tandem repeat(STR,or microsatellite)loci and a gender-identifying SRY gene,all amplified in 4 reactions using as little as 1 ng of template *** DnA samples used for between-run calibration,the system generates STR genotypes that are directly compatible with voucher tiger subspecies genetic profiles,hence making it possible to identify subspecies via bi-parentally inherited *** applied“tigrisPlex”to 12 confiscated specimens from Russia and identified 6 individuals(3 females and 3 males),each represented by duplicated samples and all designated as Amur tigers(Panthera tigris altaica)with high *** STR multiplex system can serve as an effective and versatile approach for genetic profiling of both wild and captive tigers as well as confiscated tiger products,fulfilling various conservation needs for identifying the origins of tiger samples.

关键词： Amur tiger genetic multiplex sexing short tandem repeat

Searching for the brightest stars in galaxies outside the Local Group

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Research in Astronomy and Astrophysics 2021年第4期21卷 264-270页

作者： nikolay Tikhonov olga Galazutdinova olga Sholukhova Antoniya valcheva Petko nedialkov olga Merkulova Special Astrophysical Observatory Nizhnij ArkhyzKarachai-Cherkessian RepublicRussia 369167 Department of Astronomy Sofia University1504 Sofia15 Tsar Osvoboditel Blvd.SofiaBulgaria Astronomical Institute St.Petersburg State UniversityUniversitetskii pr.28St.Petersburg198504 Russia

This paper introduces a technique for searching for bright massive stars in galaxies beyond the Local *** search for massive stars,we processed the results of stellar photometry from the Hubble Space Telescope(HST)images using the DAOPHOT and DOLPHOT *** results of such searches are demonstrated with examples of the galaxies DDO 68,M94 and nGC *** the galaxy DDO 68,the LBv star changes its brightness,and massive stars in M94 can be identified by excess in the Ha *** the galaxy nGC 1672,we measure the distance for the first time by the TRGB method,which enabled determining the luminosities of the brightest stars,likely hypergiants,in the young star formation *** far,we have performed stellar photometry on HST images of 320 northern sky galaxies located at a distance less than 12 *** allowed us to identify 53 galaxies with probable *** photometric and spectral observations of these galaxies are planned to search for massive stars.

关键词： stars:massive stars:variables:LBv galaxies:individual:M94 DDO 68 nGC 1672

Performance Analysis of Thermoacoustic Refrigerator of 10 W Cooling Power Made up of Poly-vinyl-Chloride for Different Parallel Plate Stacks by Using Helium as a Working Fluid

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Journal of Thermal Science 2021年第6期30卷 2037-2055页

作者： n v Shivakumara BHEEMSHA Arya Department of Mechanical Engineering BMS College of EngineeringBengaluru 560019India Department of Mechanical Engineering Government PolytechnicChannasandraBengaluru 560067India

Refrigerants are usually provided in the conventional refrigeration system although the refrigerants produce Chlorofluorocarbons(CFCs)and Hydro-chlorofluorocarbons(HCFCs),which are hazardous to the ***,these disadvantages can be overcome by using air or inert gas in the thermoacoustic refrigeration *** the present experimental work,helium is used as a working gas with an operating pressure range of 0.2 MPa to 1.0 MPa in order to study the performance of thermoacoustic refrigerator(TAR)which is fabricated using Poly-vinyl-Chloride(PvC).The parallel plate stacks with different porosity ratios have been considered to study the performance of *** temperature difference between the hot and cold heat exchanger and acoustic dynamic pressure were recorded by using Bruel and Kjaer data acquisition system under different operating *** effect of different operating parameters such as operating frequency(200 Hz to 600 Hz),cooling load(2 W to 10 W)and drive ratio(0.6%to 1.6%)have also been considered to study the performance of *** TAR also modeled in DeltaEC software and the results are compared with the experimental outcomes and found to be in good *** experimental results show that-2.1℃is the lowest temperature measured at cold heat exchanger by achieving the highest temperature difference of about 32.9℃.An improvement is around 36%as compared to that of previous experiments that used aluminium *** highest Coefficient of Performance(COP)and the Relative Coefficient of Performance(COPR)are found to be 2.024 and 0.217,respectively.

关键词： thermoacoustic refrigerator parallel plate stack porosity ratio temperature difference COP COPR

Gate-Dependent nonlinear Hall Effect at Room Temperature in Topological Semimetal GeTe

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Chinese Physics Letters 2023年第7期40卷 63-67页

作者： n.n.Orlova 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 nonlinear Hall effect as zero-frequency and second-harmonic transverse voltage responses to ac electric current for topological semimetal GeTe.A thick single-crystal GeTe flake is placed on the Si/SiO_(2) substrate,where the p-doped Si layer serves as a gate *** confirm that electron concentration is not gate-sensitive in thick GeTe flakes due to the gate field screening by bulk *** contrast,by transverse voltage measurements,we demonstrate that the nonlinear Hall effect shows pronounced dependence on the gate electric field at room *** the nonlinear Hall effect is a direct consequence of a Berry curvature dipole in topological media,our observations indicate that Berry curvature can be controlled by the gate electric *** experimental observation can be understood as a result of the known dependence of giant Rashba splitting on the external electric field in *** possible applications,the zero-frequency gate-controlled nonlinear Hall effect can be used for the efficient broad-band rectification.

关键词： temperature. field. curvature

Controlled Wettability of Polymers via Environmental Crazing

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Chinese Journal of Polymer Science 2022年第10期40卷 1307-1314,I0012页

作者： Alena Yu.yarysheva Larisa M.yarysheva Fedor v.Drozdov olga v.Arzhakova Aziz M.Muzafarov Faculty of Chemistry Lomonosov Moscow State UniversityLeninskieGory 1-3Moscow 119991Russia Institute of Synthetic Polymer Materials RAS ul.Profsoyuznaya 70Moscow 117393Rusia

This work highlights the benefits of environmental crazing for the control over the hydrophilic-lipophilic balance of glassy amorphous and semicrystalline polymers:poly(ethylene terephthalate)(PET)and biodegradable polycaprolactone(PCL).Task-oriented encapsulation of diverse commercial and natural hydrophilic(polyethyleneoxide,polyvinylpyrrolidone,gelatin)and hydrophobic guest additives(perfluoroorgano siloxanes,water-repellent impregnation)into mesoporous host polymer(PET,PCL)matrixes allows targeted control over the wettability of the resultant nanocomposite *** on the nature of the guest additive,the properties of the modified polymers can be varied from hydrophilic to hydrophobic:contact angle(CA)of PET can be adjusted from 47_(⊥)/38_(||)to 130_(⊥)/117_(||)°(for initial PET,CA=82°)and CA of PCL from 40°to 114°(for initial PCL CA=75°).The unique benefits of environmental crazing for structural modification are related to the universal character of this approach which can be applied to a broad range of polymers and allows preparation of diverse high-performance materials with tunable hydrophilic-lipophilic balance.

关键词： Wettability Hydrophilic-hydrophobic balance Contact angle Environmental crazing Poly(ethylene terephthalate) Polycaprolactone

InITIAL vALUE TEchnIQUES FOR THE HELMHOLTZ AnD MAXWELL EQUATIOnS

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Journal of Computational Mathematics 2007年第3期25卷 368-373页

作者： Frank natterer olga Klyubina Department of Mathematics University of MünsterGermany

We study the initial value problem of the Helmholtz equation with spatially variable wave number. We show that it can be stabilized by suppressing the evanescent waves. The stabilized Helmholtz equation can be solved numerically by a marching scheme combined with FFT. The resulting algorithm has complexity n^2 log n on a n x n grid. We demonstrate the efficacy of the method by numerical examples with caustics. For the Maxwell equation the same treatment is possible after reducing it to a second order system. We show how the method can be used for inverse problems arising in acoustic tomography and microwave imaging.

关键词： Stability of elliptic initial value problems Parabolic wave equation Inverseproblems in acoustics and electromagnetics.

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 having 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