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Research on magnetic fields of galaxies using RZ-model

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Research in Astronomy and Astrophysics 2021年第3期21卷 57-60页

作者： Evgeny Alexandrovich Mikhailov Vasilii Vladimirovich Pushkarev faculty of Physics M.V.Lomonosov Moscow State UniversityMoscow 119991Russia university of Cambridge Trinity LaneCambridgeCB21TNUnited Kingdom

The generation of magnetic fields of galaxies is usually described by the dynamo *** process is characterized by the Steenbeck-Krause-Radler equation,which is the result of averaging the magnetohydrodynamics equations by distances which are associated with the size of turbulent cells in the interstellar *** equation is quite difficult to solve both from an analytical and numerical point of *** galaxies,the no-z approximation is widely *** describes the magnetic fields in thin *** such objects,where it is important to study the vertical structure of the field,it is not very applicable,so it is quite useful to adopt the RZ-model,which takes into account the dependence of the distance from the equatorial *** our research we have obtained the critical values of the dynamo number for galaxies with large *** have also described typical z-structure for the magnetic ***,we have demonstrated that it is possible to generate dipolar magnetic fields.

关键词： general:dynamo,magnetic fields methods:numerical galaxies:magnetic fields

Study of tree shrew biology and models: A booming and prosperous field for biomedical research

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Zoological Research 2024年第4期45卷 877-909页

作者： Yong-Gang Yao Li Lu Rong-Jun Ni Rui Bi Ceshi Chen Jia-Qi Chen Eberhard Fuchs Marina Gorbatyuk Hao Lei Hongli Li Chunyu Liu Long-Bao Lv Kyoko Tsukiyama-Kohara Michinori Kohara Claudia Perez-Cruz Gregor Rainer Bao-Ci Shan Fang Shen An-Zhou Tang Jing Wang Wei Xia Xueshan Xia Ling Xu Dandan Yu Feng Zhang Ping Zheng Yong-Tang Zheng Jumin Zhou Jiang-Ning Zhou Key Laboratory of Genetic Evolution and Animal Models Yunnan Key Laboratory of Animal Models and Human Disease MechanismsKunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650204China National Research Facility for Phenotypic&Genetic Analysis of Model Animals(Primate Facility) and National Resource Center for Non-Human PrimatesKunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650107China KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650204China Kunming College of Life Science University of Chinese Academy of SciencesKunmingYunnan 650204China Mental Health Center and Psychiatric Laboratory West China HospitalSichuan UniversityChengduSichuan 610041China Sichuan Clinical Medical Research Center for Mental Disorders ChengduSichuan 610044China German Primate Center Leibniz Institute of Primate ResearchGöttingen 37077Germany Department of Optometry and Vision Science School of OptometryUniversity of Alabama at BirminghamBirminghamAL 35294USA state Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhanHubei 430071China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhanHubei 430074China Soong Ching Ling Institute of Maternity and Child Health International Peace Maternity and Child Health HospitalShanghai Jiao Tong University School of MedicineShanghai 200030China Transboundary Animal Diseases Center Joint Faculty of Veterinary MedicineKagoshima UniversityKagoshima-cityKagoshima 890-8580Japan Department of Microbiology and Cell Biology Tokyo Metropolitan Institute of Medical ScienceTokyo 156-8506Japan Pharmacology Department CinvestavMexico City 07360Mexico Department of Medicine University of FribourgFribourg CH-1700Switzerland Beijing Engineering Research Center of Radiog

The tree shrew(Tupaia belangeri)has long been proposed as a suitable alternative to non-human primates(NHPs)in biomedical and laboratory research due to its close evolutionary relationship with *** recent years,significant advances have facilitated tree shrew studies,including the determination of the tree shrew genome,genetic manipulation using spermatogonial stem cells,viral vector-mediated gene delivery,and mapping of the tree shrew brain ***,the limited availability of tree shrews globally remains a substantial challenge in the ***,determining the key questions best answered using tree shrews constitutes another *** shrew models have historically been used to study hepatitis B virus(HBV)and hepatitis C virus(HCV)infection,myopia,and psychosocial stress-induced depression,with more recent studies focusing on developing animal models for infectious and neurodegenerative *** these efforts,the impact of tree shrew models has not yet matched that of rodent or NHP models in biomedical *** review summarizes the prominent advancements in tree shrew research and reflects on the key biological questions addressed using this *** emphasize that intensive dedication and robust international collaboration are essential for achieving breakthroughs in tree shrew *** use of tree shrews as a unique resource is expected to gain considerable attention with the application of advanced techniques and the development of viable animal models,meeting the increasing demands of life science and biomedical research.

关键词： Tree shrew Animal model Neurodegenerative diseases Infectious diseases Neuroscience Phenome

Distribution changes of woody plants in Western Iran as monitored by remote sensing and geographical information system:a case study of Zagros forest

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Journal of Forestry Research 2017年第1期28卷 145-153页

作者： Mansour Karkon Varnosfaderani Rasoul Kharazmi Aliakbar Nazari Samani Mohammad Reza Rahdari Seid Hamid Matinkhah Nasrollah Aslinezhad state university of Land Use Planning MoscowRussianFederation St.Petersburg state university PetersburgRussianFederation faculty of Natural Resource University of TehranKarajIran Isfahan university of Technology IsfahanIran faculty of Water and Soil Zabol UniversityZabolIran

The status of woody plants in dry-land systems is a fundamental determinant of key ecosystem processes. Monitoring of this status plays an important role in understanding the dynamics of woody plants in arid and semi-arid ecosystems. The present study determined the dynamism of the Zagros forests in Iran using Remote Sensing and Geographic Information System techniques and statistical science. The results show that the density of trees varied from 10 to 53 % according to the physio- graphic and climatic conditions of semi-arid regions. The best and lowest correlation between vegetation indices and forest density were obtained for the global environmental monitoring index （GEMI; R2 = 0.94） and soil adjust vegetation index （R2 = 0.81）, respectively. GEMI is used to monitor land use changes over a 10-year period. Results show that 2720 ha2 of forest have been destroyed by human interference and tillage on steep slopes during this period which also resulted in the loss of the fertile soil layer. GEMI determined the areas with a biomass of trees and could normally separate border regions with low bio- mass density of trees from regions without canopy cover. The results revealed that assessment of forest and vegetation cover in arid and semi-arid arduous forest regions using satellite digital numbers and ordinary sampling is subject to uncertainty. A stratified grouping procedure should be established to increase the accuracy of assessment.

关键词： Monitoring Woody plants Vegetation index RS GIS Zagros forest Iran

Micromagnetic Structure of Co-Rich Amorphous Microwires

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Journal of Materials Science & Technology 2000年第2期16卷 183-185页

作者： E.E.Shalyguina and L.M.Bekoeva (Physical faculty, moscow state university, 119899, moscow, Russia) Kyung-Ho Shin (Korea Institute of Science & Technology , P.O. Box 131, Cheongryang, Seoul 130-650, Korea) Physical faculty Moscow State University 119899 Moscow Russian Federation Korea Institute of Science and Technology P.O. Box 131 Cheongryang Seoul 130-650 South Korea

Results on the magneto-optical investigation of near-surface micromagnetic structure (MMS) of Co69Fe4Si12B15 amorphous wires 10～50 μm in diameter are presented. The wires were prepared by the rapid solidification technique. The magnetic field H was applied along or perpendicular to the wire length. By scanning the light spot of 1 μm-diameter along the wire length, distributions of magnetization components (both parallel and perpendicular to the applied magnetic field) and also local hysteresis characteristics of the wires were measured. It was experimentally established that owing to the compressive stresses from quenching coupled with negative magnetostriction of Co-rich amorphous materials, the examined microwires have a circumferential magnetic anisotropy. In consequence, there are the near-surface alternate left- and right-handled circular domains in these samples. The dependencies of the circular domain width on the wire diameter and length were found. It was discovered that in the axial magnetic field local hysteresis loops are unhysteretic. It was proved that in this case the dominant mechanism of the wire magnetization reversal is rotation of local magnetization vectors in circular domains.

关键词： Rich Micromagnetic Structure of Co-Rich Amorphous Microwires MMS

Gastric cancer:Prevention,screening and early diagnosis

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World Journal of Gastroenterology 2014年第38期20卷 13842-13862页

作者： Victor Pasechnikov Sergej Chukov Evgeny Fedorov Ilze Kikuste Marcis Leja Stavropol state Medical university moscow state Medical university faculty of Medicine University of Latvia Digestive Diseases Centre GASTRO Department of Research Riga East University Hospital

Gastric cancer continues to be an important healthcare problem from a global perspective. Most of the cases in the Western world are diagnosed at late stages when the treatment is largely ineffective. Helicobacter pylori(H. pylori) infection is a well-established carcinogen for gastric cancer. While lifestyle factors are important,the efficacy of interventions in their modification,as in the use of antioxidant supplements,is unconvincing. No organized screening programs can be found outside Asia(Japan and South Korea). Although several screening approaches have been proposed,including indirect atrophy detection by measuring pepsinogen in the circulation,none of them have so far been implemented,and more study data is required to justify any implementation. Mass eradication of H. pylori in high-risk areas tends to be cost-effective,but its adverse effects and resistance remain a concern. Searches for new screening biomarkers,including microRNA and cancer-autoantibody panels,as well as detection of volatile organic compounds in the breath,are in progress. Endoscopy with a proper biopsy follow-up remains the standard for early detection of cancer and related premalignant lesions. At the same time,new advanced high-resolution endoscopic technologies are showing promising results with respect to diagnosing mucosal lesions visually and targeting each biopsy. New histological risk stratifications(classifications),including OLGA and OLGIM,have recently been developed. This review addresses the current means for gastric cancer primary and secondary prevention,the available and emerging methods for screening,and new developments in endoscopic detection of early lesions of the stomach.

关键词： Gastric cancer Helicobacter pylori

Assessing suspended sediment fluxes with acoustic Doppler current profilers:case study from large rivers in Russia

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Big Earth Data 2022年第4期6卷 504-526页

作者： Sergey Chalov Vsevolod Moreido Victor Ivanov Aleksandra Chalova faculty of Geography Lomonosov Moscow State UniversityMoscowRussia Institute of Physics Kazan Federal UniversityKazanRussia Flood Hydrology Lab Water Problems Institute of Russian Academy of SciencesMoscowRussia

Surrogate measures are becoming increasingly used to measure suspended sediment flux,but only few particular computer techniques of data processing are recently *** study demonstrates capabilities of acoustic Doppler current profilers(ADCPs)to infer information regarding suspended-sand concentrations in river systems and calculate suspended sediment flux via big data analytics which includes process of analyzing and data mining of measurements based on ADCP signal backscatter intensity *** present here specific codes done by R language using RStudio software with open-source tidyverse and plotly packages aimed to generate tables containing data of suspended load for cells,verticals and whole cross-section based on backscattering values from 600 kH Teledyne RDInstruments RioGrande WorkHorse ADCP unit,as well perform estimates of morphometric,suspended sediment concentration(SSC)and velocity characteristics of the *** developed tools enabled to process large data array consisting of over 56,526,480 geo-referenced values of river depth,streamflow velocity,and backscatter intensity for each river cross-section measured at six case study sites in Russia.

关键词： Big data ADCP backscatter intensity sediment transport

Orbits of Real Semisimple Lie Groups on Real Loci of Complex Symmetric Spaces

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Acta Mathematica Sinica,English Series 2018年第3期34卷 439-453页

作者： Stéphanie CUPIT-FOUTOU Dmitry A.TIMASHEV Ruhr-Universitat Bochum Fakultat fiir Mathematik D-44780 Bochum Germany Lomonosov moscow state university Faculty of Mechanics and Mathematics Department of Higher Algebra 119991 Moscow Russia

Let G be a complex semisimple algebraic group and X be a complex symmetric homogeneous G-variety. Assume that both G, X as well as the G-action on X are defined over real *** G（R） acts on X（R） with finitely many orbits. We describe these orbits in combinatorial terms using Galois cohomology, thus providing a patch to a result of Borel and Ji.

关键词： Semisimple group symmetric space real point orbit Galois cohomology

Polyphony of domestic dog whines and vocal cues to body size

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Current Zoology 2021年第2期67卷 165-176页

作者： Olga V.SIBIRYAKOVA Ilya A.VOLODIN Elena V.VOLODINA Department of Vertebrate Zoology Faculty of BiologyLomonosov Moscow State UniversityMoscow 119234Russia Department of Behaviour and Behavioural Ecology A.N.Severtsov Institute of Ecology and EvolutionRussian Academy of SciencesMoscow 119071Russia

In domestic dogs Canis familiaris,vocal traits have been investigated for barks and growls,and the relationship between individual body size and vocal traits investigated for growls,with less corre-sponding information for *** this study,we examined the frequency and temporal traits of whines of 20 adult companion dogs(9 males,11 females),ranging in body mass from 3.5 to 70.0 kg and belonging to 16 *** whines(26-71 per individual,824 in total)were recorded in condi-tioned begging contexts modeled by dog *** had 3 independent fundamental fre-quencies:the low,the high and the ultra-high that occurred singly as monophonic calls or simul-taneously as 2-voice biphonic or 3 voice polyphonic *** the smallest to largest dog,the upper frequency limit varied from 0.24 to 2.13 kHz for the low fundamental frequency,from 2.95 to 10.46 kHz for the high fundamental frequency and from 9.99 to 23.26 kHz for the ultra-high funda-mental *** individuals,the low fundamental frequency was lower in monophonic than in biphonic whines,whereas the high fundamental frequency did not differ between those whine *** frequency variables of the low,high,and ultra-high fundamental frequencies cor-related negatively with dog body *** duration,no correlation with body mass was *** discuss potential production mechanisms and sound sources for each fundamental frequency;point to the acoustic similarity between high-frequency dog whines and rodent ultrasonic calls and hypothesize that ultra-high fundamental frequencies function to allow private,"tete-a-tete"com-munication between members of social groups.

关键词： acoustic communication Canis familiaris companion dogs high-frequency calls nonlinear phenomena vocalization

Recent strategies to improve moisture stability in metal halide perovskites materials and devices

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Journal of Energy Chemistry 2022年第2期31卷 219-235页

作者： Chenxiao Zhou Alexey B.Tarasov Eugene A.Goodilin Pengwan Chen Hao Wang Qi Chen School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China faculty of Materials Science Lomonosov Moscow State UniversityLenin Hills119991 MoscowRussia Department of Chemistry Lomonosov Moscow State UniversityLenin Hills119991 MoscowRussia state Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

At present,the stability of the new generation of solar cells based on hybrid perovskites is the bottleneck for their practical *** effects,high temperature,ultraviolet light,humidity and other known or still unknown factors might cause reduction of effectiveness or even irreversible loss of materials properties due to decomposition of functional layers within perovskite solar cells(PSCs).These factors alone have a serious impact on each component of the device,while their combinations lead to much more complicated effects and *** review focuses on the stability of PSCs and the degradation of the device in a humid *** assess the instability factors and deep-seated principles of evolution of the device structure in a humidity environment with the emphasis on the influence on their *** related solutions are reviewed from the perspective of the encapsulation,perovskite active layer,carrier transport layer and *** with the latest research,we believe that the waterproof strategy of PSCs requires either tight encapsulation or thorough modifications in the device ***,it is important to develop feasible strategies to improve the overall device stability over humid according to the target characteristics of various devices.

关键词： Perovskite solar cells Water Stability Composition Encapsulation