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Rodent burrow network dynamics under human-induced landscape transformation from desert to steppe in Kalmykian rangelands

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Integrative Zoology 2019年第4期14卷 410-420页

作者： Elena sURKOVA sergey POPOV Andrey TCHABOVsKY A.N.severtsov Institute of Ecology and Evolution Russian Academy of SciencesMoscowRussia Department of Vertebrate Zoology Lomonosov Moscow State UniversityMoscowRussia

Rodents play an important role in rangelands through the engineering of extensive burrow systems,which provides key habitats for many animal and plant *** have analyzed the long-term variation in the abundance and distribution of rodent burrows in grazing ecosystems of southern Russia(Kalmykia)under the landscape change from desert to steppe caused by the drastic reduction of livestock after the collapse of the UssR in the early *** conducted burrow surveys in the“desert”(1980)and“steppe”(2017)periods on 193-km *** found considerable changes in burrow abundance and distribution,as well as evidence of desert habitat fragmentation and isolation caused by the expansion of tall-grass *** of the open-dwelling diurnal ground squirrel(spermophilus pygmaeus),the dominant and the keystone species during the“desert”period,almost completely disappeared from the rodent burrow network by 2017,indicating significant habitat *** contrast,the burrows of the folivorous social vole(Microtus socialis)which was rare in the 1980s,became abundant and ubiquitously *** burrow density of the desert-dwelling psammophilous midday gerbil(Meriones meridianus)decreased,while the distances between occupied patches increased,indicating desert habitat fragmentation and loss of population *** of the folivorous tamarisk gerbils(***)were recorded only sporadically in both 1980 and *** observed changes in the rodent burrow network,the key component of grazing ecosystems,correlate with rodent species ecology and can have long-term and important consequences for ecosystem functioning.

关键词： burrows fragmentation grazing impact keystone species rodents

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Russian school of the theory and geometry of gearing： Its origin and golden period （1935-1975）

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Frontiers of Mechanical Engineering 2016年第1期11卷 44-59页

作者： Dmitry BABICHEV sergey LAGUTIN Natalya BARMINA Department of Applied Mechanics Tyumen State Oil and Gas University Tyumen 625000 Russia Electrostal Plant of Heavy Machine Engineering Electrostal City144012 Russia Institute of Mechanics Kalashnikov Izhevsk State Technical Universitylzhevsk 426069 Russia

During the second half of the twentieth century, soviet scientists were among the world leaders in the theory and geometry of gearing or the theoretical fundamentals of designing gears and gear-cutting tools. The authors of the current paper review works related to the development of the theory of gearing （TG） written in Russian from the mid-1930s to the present. Overall, the review covers more than 400 publications of nearly 200 authors （among more than 1000 studied works）. This review involves some works on gear strength and accuracy to attract more experts. This paper presents a short list of works from the seventeenth century to the nineteenth century and discusses the basic concepts of the TG. This paper also includes a review of more than 160 papers in Russian for the period of 1935-1975, which is the ＂golden age＂ of the TG. The main features and achievements during this period are also considered. The distinctive feature of this review is the use of diagrams that visually present TG experts and the dates and themes of their published works. The diagrams also show the following aspects： 1） The most popular and important themes in a specific period, 2） the most important publications on the themes of interest to readers, and 3） the direction of the works and scope of interests of every researcher.

关键词： theory of gearing (TG) gear geometry,generating surface gear synthesis gear analysis

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Generation of dual and quad‑optical frequency combs in the injected radiation free mode‑locked frequency‑shifted feedback laser

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Frontiers of Optoelectronics 2023年第3期16卷 43-56页

作者： sergey N.Mantsevich Ekaterina I.Kostyleva Andrey N.Danilin Vladimir s.Khorkin Physics Department M.V.Lomonosov Moscow State UniversityMoscow 119991Russia Russian Quantum Center(RQC) Skolkovo 143026Russia

The results of an optoelectronic system—frequency-shifted feedback(FsF)laser experimental examination are *** considered FsF laser is seeded only with optical amplifer spontaneous emission(AsE)and operates in the mode-locked regime,whereby the output radiation is sequence of short pulses with a repetition rate determined by the delay time in its optical feedback *** the frequency domain,the spectrum of such a pulse sequence is an optical frequency comb(OFC).These OFCs we call *** consider the possibility of tunable acousto-optic(AO)dual and quad-comb frequency spacing downconversion in the FsF laser seeded with AsE and operating in the mode-locked *** examined system applies a single frequency shifting loop with single AO tunable flter as the frequency shifter that is fed with several radio frequency signals *** initial OFCs with frequency spacing of about 6.5 MHz may be obtained in the wide spectral range and their width,envelope shape and position in the optical spectrum may be *** dual-combs are obtained with a pair of initial OFCs aroused by two various ultrasound waves in the acousto-optic tunable flter(AOTF).The dual-combs frequency spacing is determined by the frequency diference of the signals applied to the AOTF piezoelectric transducer and can be tuned *** quad-combs are obtained with three initial OFCs,forming a pair of dual-combs,appearing when three ultrasound frequencies feed the AOTF *** quad-combs frequency spacing is defned by the diference between the frequency spacing of ***-combs with more than 5000 spectral lines and tunable frequency spacing are *** successive frequency downconversion gives the possibility to reduce the OFC frequency spacing form several MHz for initial OFC to tens of kHz for quad-combs.

关键词： Frequency-shifted feedback laser Optical frequency combs Acousto-optics Dual-combs Quad-combs

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A novel technique for unilateral dissection of the penile neurovascular bundle to prevent loss of penile sensation during treatment of Peyronie's disease-Initial results of a pilot study

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Current Urology 2023年第4期17卷 299-302页

作者： Alexandr M.Pinkhasov Matthew Beamer Daniel shulman Rachel Yakubov Esther Pinkhasov sergey Kravchick Department of Urology SUNY Upstate Medical University HospitalSyracuseNY 13202USA

Background:Plaque incision/excision and grafting are surgical techniques used to treat patients with Peyronie's disease who are refractory to less invasive interventions,have severe penile curvature,or have an hourglass ***,the procedure carries the risk of penile sensory loss because of the need for dissection of the neurovascular bundle(NVB).The aim of this study was to assess the feasibility of a novel technique for unilateral NVB dissection and its ability to preserve penile sensitivity while maintaining adequate correction of the penile *** and methods:Charts of patients who underwent unilateral NVB dissection during Peyronie's plaque incision/excision and grafting were retrospectively *** patients received preprocedural intracavernosal injections of TriMix,and the curvature was measured to be>70 *** 3 cases,an incision and minimal excision of the plaque were performed at the point of maximum curvature on the concave side of the *** 3 cases,Tutoplast allografts(Coloplast Us,Minneapolis,MN)were used,whereas autografts were used in 2 other *** patients were examined at 1,3,and 6 months after the procedure when curvature and penile sensation were ***:Five patients underwent this *** mean age of patients was 55 years(45-70 years).All plaques were dorsally *** mean preoperative curvature was 78 degrees(75-90 degrees).At the 6-month follow-up,all patients hads residual curvature and were satisfied with their cosmetic *** 1 patient continued with phosphodiesterase-5 inhibitors to improve potency at the 6-month *** patients reported normal penile glans *** patients experienced decreased sensation at the site of NVB dissection,but this was only detected when compared with the contralateral *** 2 patients reported a difference after 6 months,and only a minor area of involvement was ***:Unilateral NVB dissection is a feasi

关键词： Peyronie's disease Neurovascular bundle dissection

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Determination of Iron in Water solution by Time-Resolved Femtosecond Laser-Induced Breakdown spectroscopy

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Plasma science and Technology 2015年第11期17卷 975-978页

作者： sergey s.GOLIK Alexey A.ILYIN Michael Yu.BABIY Yulia s.BIRYUKOVA Vladimir V.LIsITsA Oleg A.BUKIN Far Eastern Federal University Institute of Automation and Control Processes Far Eastern BranchRussian Academy of Sciences

The influence of the energy of femtosecond laser pulses on the intensity of Fe I （371.99 nm） emission line and the continuous spectrum of the plasma generated on the surface of Fe^3＋ water solution by a Ti： sapphire laser radiation with pulse duration 〈45 fs and energies up to 7 mJ is determined. A calibration curve was obtained for Fe3＋ concentration range from 0.5 g/L to the limit of detection in water solution, and its saturation was detected for concentrations above 0.25 g/L, which is ascribed to self-absorption. The 3σ- limit of detection obtained for Fe in water solution is 2.6 mg/L in the case of 7 mJ laser pulse energy. It is found that an increase of laser pulse energy insignificantly affects on LOD in the time-resolved LIBs and leads to a slight improvement of the limit of detection.

关键词： femtosecond laser-induced breakdown spectroscopy LIBs femtosecond plasma iron analysis of water atomic emission spectroscopy limit of detection

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sinterability of nanopowders of terbia solid solutions with scandia,yttria,and lutetia

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Journal of Advanced Ceramics 2018年第4期7卷 362-369页

作者： stanislav s.BALABANOV Dmitry А.PERMIN Elena Ye.ROsTOKINA sergey V.EGOROV ANDrey A.sOROKIN G.G.Devyatykh Institute of Chemistry of High-Purity substances RAs Federal Research Center the Institute of Applied Physics RAS

The synthesis of nanopowders of terbia compounds with scandia, yttria, and lutetia was carried out using a self-propagating high-temperature synthesis method involving a mixture of nitrates of metals and glycine as a precursor. The nanopowder phase transformations were investigated using X-ray diffraction analysis. It was found that lutetia has a negligible effect on the phase formation in terbia. On the other hand, yttrium and scandium ions significantly suppressed crystallization. The densification kinetics of nanopowders of the Tb_2O_3 compounds and the microstructure of ceramics after microwave sintering were studied using dilatometry and scanning electron microscopy. The introduction of scandia, yttria, or lutetia contributed to the intensification of the densification of the terbia ceramics when heated in a microwave field. Near full-density materials of terbia solid solutions with lutetia and yttria were obtained at about 1600–1640 ℃. The ceramics of scandia–terbia compounds contained the second phase, which causes light scattering.

关键词： terbia microwave sintering X-ray analysis ceramics

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Economic Dispatch Considering Hourly Capacity Allocation with a Variable Renewable and Hydro-Based Generation Portfolio

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Energy and Power Engineering 2022年第10期14卷 594-614页

作者： Roney N. Vitorino Dorel s. Ramos Karen Tapia-Ahumada sergey Paltsev John M. Reilly Energy Research Office Rio de Janeiro Brazil Polytechnic school University of Sao Paulo Sao Paulo Brazil Massachusetts Institute of Technology Cambridge USA

The objective of this paper is to assess an economic dispatch considering a power system portfolio, which includes predominant amount of hydro power and increasing quantities of intermittent renewables in relation to the total electric capacity. With growing importance of intermittent wind and solar generation taking part into power systems worldwide, there is need for greater chronological resolution to estimate the flexibility of the power system to offer firm capacity. In this way, a linear optimization model operating hourly is developed to calculate the minimum power system cost, while stablishing the capacity allocation to meet the projected load throughout one-year simulation, as an estimation of how the hourly economic dispatch impacts the scheduling of generators belonging to a power system with this portfolio composition. A central focus is how to operate the available hydro capacity to back up intermittent renewables, evaluating the physical hydro operating constraints, monthly energy balance and maximum power availability. A case study was simulated based on the Brazil’s power system configuration, showing that existing hydro capacity provide hourly flexibility to back-up intermittent renewables, potentially saving 1.2 Billion R$, about 3.6% of total system cost referred to 2019. It is worthwhile to realize that the developed methodology can be employed to other power systems with similar capacity portfolio structure for the purpose of calculating its optimum allocation for a specified region and target year.

关键词： Economic Dispatch Energy Planning Operation Flexibility Power system Transmission system Variable Renewable Energy

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Dynamics of magnetic flux tubes and IR-variability of young stellar objects

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Research in Astronomy and Astrophysics 2018年第8期18卷 13-20页

作者： sergey Khaibrakhmanov Alexander Dudorov Andrey sobolev Kourovka Astronomical Observatory Ural Federal University Theoretical Physics Department Chelyabinsk State University

We simulate the dynamics of slender magnetic flux tubes （MFTs） in the accretion disks of T Tauri stars. The dynamical equations of our model take into account aerodynamic and turbulent drag forces, and the radiative heat exchange between the MFT and ambient gas. The structure of the disk is calculated with the help of our MHD model of the accretion disks. We consider the MFTs formed at distances of 0.027 - 0.8 au from the star with various initial radii and plasma betas β0. The simulations show that MFTs with a weak magnetic field （β0 = 10） rise slowly with speeds less than the speed of sound. MFTs withβ0 = 1 form an outflowing magnetized corona above the disk. strongly magnetized MFTs （β0 = 0.1） can cause outflows with velocities 20 - 50 km s-1. The tubes rise periodically over times from several days to several months according to our simulations. We propose that periodically rising MFTs can absorb stellar radiation and contribute to the IR-variability of young stellar objects.

关键词： accretion disks- instabilities- magnetohydrodynamics (MHD) - protoplanetary disks

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On Modifications of Continuous and Discrete Maximum Principles for Reaction-Diffusion Problems

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Advances in Applied Mathematics and Mechanics 2011年第1期3卷 109-120页

作者： Istvan Farago sergey Korotov Tamas szabo Department of Applied Analysis and Computational Mathematics Eotvos Lorand UniversityH–1117BudapestPazmany P.s.1/c.Hungary BCAM-Basque Center for Applied Mathematics Bizkaia Technology ParkBuilding 500E–48160 DerioBasque CountrySpain

In this work,we present and discuss some modifications,in the form of two-sided estimation(and also for arbitrary source functions instead of usual sign-conditions),of continuous and discrete maximum principles for th... 详细信息

关键词： Reaction-diffusion problem maximum principle discrete maximum principle monotone matrix two-sided a priori estimation code validification

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Application of aluminum foil for “strain sensing” at fatigue damage evaluation of carbon fiber composite

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中国科学：物理学、力学、天文学英文版 2014年第1期57卷 59-64页

作者： PANIN sergey BURKOV Mikhail LYUBUTIN Pavel ALTUKHOV Yurii Laboratory of Polymer Composite Materials Institute of Strength Physics and Material Science 634021 Akademicheskii avenue 2/4Tomsk Russia National Research Tomsk Polytechnic University 634050 Lenina avenue 30 office 127 Tomsk Russia

surface layer of a loaded solid is an individual structural level of deformation that was shown numerously within concept of physical *** gives rise to advance in its deformation development under loading as well as allows using this phenomenon to sense the strain induced structure *** is of specific importance for composite materials since they are highly heterogeneous while estimating their mechanical state is a topical applied *** tests of carbon fiber composite specimens were carried out for cyclic deformation estimation with the use of strain sensors made of thin(80μm)aluminum foil glued to the specimen’s *** surface images were captured by DsLR camera mounted onto an optical *** relief to form during cyclic loading was numerically estimated using different parameters:dispersion,mean square error,universal image quality index,fractal dimension and energy of Fourier *** results are discussed in view of deformation mismatch in thin foil and bulk specimen and are offered to be applied for the development of structural Health Monitoring(sHM)approach.

关键词：碳纤维复合材料应变传感器疲劳试验应用损伤评估铝箔物理细观力学循环变形

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