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Evidence for the existence of localized plastic flow au-to-waves generated in deforming metals

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Natural Science 2010年第5期2卷 476-483页

作者： lev B. Zuev Svetlana A. Barannikova 不详

The localized plastic flow auto-waves observed for the stages of easy glide and linear work hardening in a number of metals are considered. The propagation rates were determined expe- rimentally for the auto-waves in question with the aid of focused-image holography. The dispersion relation of quadratic form derived for localized plastic flow auto-waves and the dependencies of phase and group rates on wave number are discussed. A detailed comparison of the quantitative characteristics of phase and group waves has revealed that the two types of wave are closely related. An invariant is introduced for localized plastic flow phenomena occurring on the micro-and macro-scale levels in the deforming solid.

关键词： Metallic Materials Mechanical Testing Optical Interferometry Strengthening and Mechanisms Crystal Plasticity Fracture

Plastic Flow Macrolocalization: Autowave and Quasi-Particle

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Journal of Modern Physics 2010年第1期1卷 1-8页

作者： lev B. Zuev Svetlana A. Barannikova 不详

A new approach is proposed to describe the autowave processes responsible for plastic deformation localiza-tion in metals and alloys. The existence of a quasi-particle, which corresponds to a localized plastic flow autowave, is postulated and its characteristics are determined. The above postulate leads to a number of cor-ollaries and quantitative assessments that are considered herein. The deformation processes occurring on the macro- and micro-scale levels are found to be directly related.

关键词： Localization Plastic Deformation Autowave Quasi-Particle

Cytological Investigation of Pollen Development in Sorghum Line with Male Sterility Induced by Sodium Ascorbate in Tissue Culture

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American Journal of Plant Sciences 2013年第7期4卷 11-18页

作者： Marina I. Tsvetova lev A. Elkonin Department of Biotechnology Agricultural Research Institute for South-East Region Saratov Russia.

Investigation of male sterility mutations is an effective approach for identification of genes involved in anther and pollen development. The comparison of “cytological phenotypes” of newly induced mutants with phenotypes determined by already known genes favors elucidation of genetic control of diverse microsporo- and gametogenesis stages. In this paper, we describe pollen development in the grain sorghum line Zh10-asc1 with mutation of male sterility. This line was obtained from callus culture treated by sodium ascorbate. A wide spectrum of abnormalities in microsporogenesis have been found, such as cytomixis, chromosomal laggards, chromosome disjunction, adhesion of chromosomes, disturbed cytokinesis, and others. In tapetum, the cells with one nucleus, with unequal nuclei, and with micronuclei have been observed. During pollen grain (PG) maturation abnormalities in starch accumulation and delay of development often took place. In mature anthers, a variety of pollen grain types have been revealed: fertile, of irregular shape, incompletely filled with starch, PGs delayed at the uni-nucleate or bi-nucleate gametophyte stages, with partially or fully degenerated contents, and with abnormal coloration. Variation in spectrum and the frequency of disturbances between the flowers of one and the same plant have been revealed. The reasons for significant genetic and epigenetic instability are discussed.

关键词： Male Sterility Microsporogenesis Sodium Ascorbate In Vitro Mutagenesis Genetic Instability Sorghum bicolor (L.) Moench

Visual guidelines and tutoring in pediatric urological surgery

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Current Urology 2024年第1期18卷 18-22页

作者： Stanislav Kotcherov Shahar Rotem Jawdat Jaber Galit Avraham Gennady lev Michal Darmon Yudith Gabay Boris Chertin Department of Pediatric Urology Shaare Zedek Medical CenterFaculty of MedicineHebrew UniversityJerusalemIsrael Department of Pediatric Surgery Shaare Zedek Medical CenterFaculty of MedicineHebrew UniversityJerusalemIsrael The Operation Room Shaare Zedek Medical CenterJerusalemIsrael

Background:The aim of this prospective randomized study was to evaluate the impact of visual guidelines(picture book)and parents tutoring on pediatric urological surgery on parent's stress and anxiety,the number of postoperative contacts,and *** and methods:Following institutional ethical committee approval,a special picture book reflecting different stages of the convalescent period following multiple types of pediatric urological surgery was *** were randomly divided into 2 groups in which 33 parents in Group 1 received the picture book in addition to routine instructions prior to the surgery and 31 in Group 2 received only routine postoperative *** parents were asked to answer a questionnaire(Amsterdam Preoperative Anxiety and Information Scale)regarding the level of anxiety before surgery and immediately after surgery in the recovery *** number of postoperative parent's calls,nonplaned emergency room visits,and complications were ***:No statistically significant difference in perioperative parental anxiety was found(p=0.88).The visual tutoring group had a significantly lower rate of emergency room admissions(6.6%vs.18.6%,p=0.0433),however parents from this group made a higher number of postoperative calls(9.9%vs.3.1%,p=0.38).Two(6.6%)from the tutoring group expressed their desire to omit visual counseling in future surgical preparation and 4(13.2%)did not have an *** satisfaction with regards to the preoperative counseling and information and the number of postoperative complications was similar in both ***:Visual tutoring does not add any value to parental anxiety but seems helpful in reducing postoperative emergency room *** parents preferred to exclude visual information from future preoperative counseling.

关键词： Anesthesia Children Hypospadias Pediatric case Questionnaires

Two Algorithms of Power Loading for MCM System in Nakagami Fading Channel

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International Journal of Communications, Network and System Sciences 2010年第2期3卷 208-211页

作者： lev GOLDFELD Vladimir LYANDRES Lior TAKO 不详

We consider two non-iterative algorithms of adaptive power loading for multicarrier modulation (MCM) system, The first one minimizes the average power of the system transmitter and ensures the preset average bit-error rate, while the second reduces the average transmitting power subject to the given values of demanded bit-error rate and of the outage probability. The algorithms may be used for power-efficient management of the up-link in cellular communication, where mobile terminals use rechargeable batteries, or of the downlink in satellite communication with solar power source of a transponder. We present performance analysis of the adaptive MCM systems supported by computer simulation for the case of the m-Nakagami fading and additive white Gaussian noise in the forward and backward channels. Evaluation of the power gain of the proposed strategies and its comparison with uniform power loading shows that the gain depends on the fading depth and average signal to noise ratio in the system sub-channels.

关键词： MCM Fading Channel Adaptive Power Loading

Regulated Fishery Is Beneficial for the Sustainability of Fish Population in Lake Kinneret (Israel)

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Open Journal of Ecology 2015年第10期5卷 513-527页

作者： Moshe Gophen Oren Sonin Menachem lev Gregory Snovsky Migal-Scientific Research Institute Kiryat Shmone Israel The Fisheries Department Israeli Ministry of Agriculture and Rural Development Tiberias Israel Kibutz Ein-Gev Fishery Branch MP Jordan Valley Israel

Analysis of long-term data-sets of limnological and ichthyological features of the Lake Kinneret ecosystem structure revealed evidence that the decline of fish landings during 2007-2008 was not an unpredicted crisis and included only Tilapias, and mostly S. galilaeus. Several factors were found to be responsible for the decline and recovery afterwards: decline of stocking, enhancement of population size of food competitors (Bleaks), the use of smaller mesh size of fishing nets, increase of predation pressure by Cormorants, the burst of Viral Disease, natural cyclic oscillation of ENSO event and its higher frequencies and intensities during the 2000’s. Therefore, recommendations aimed at ceased fishing are not justified and fishery continuation is correct: renewal of Bleaks fishing effort, improvement of fishing legislations, enforcement and management of fish stocking, and efficient implementation of Cormorants deportation.

关键词： Sarotherodon galilaeus Bleaks Fishery Crisis Cormorants Viral Disease Environmental Conditions

Molecular Materials for Energy Storage

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Materials Sciences and Applications 2018年第6期9卷 517-525页

作者： lev Mourokh Carine Edder Wolfgang Mack Pavel Lazarev Capacitor Sciences Inc. Menlo Park USA Department of Physics Queens College of the City University of New York Flushing USA The Graduate Center of CUNY New York NY USA

We map the requirements and design rules for dielectric materials that target large scale energy storage applications of electrostatic capacitors. The molecular unit (dielectrophore) must contain three main components: a polarizable subunit having large electric dipole, an isolating subunit which prevents current leakage, and a structural element that promotes self-assembly of molecules in solution and in mesophase and promotes crystallization in the process of film formation. This structural subunit is necessary for high molecular density and enhanced resistivity of film. The process engineering steps required for the supramolecular assembly and crystal film formation (cascade crystallization) are addressed.

关键词： Capacitor Molecular Dielectrics Molecular Design Polarization Induced Electric Dipole

Development of 3-D Gravity-Magnetic Models of the Earth’s Crust of Azerbaijan and Adjacent Areas: an Overview

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Positioning 2011年第2期2卷 84-102页

作者： lev V. Eppelbaum Boris E. Khesin 不详

Azerbaijan is located in the Alpine Himalayan collisional zone and is characterized by its complex and variable geological structure. To study Azerbaijan’s deep structure, twelve main regional interpreting profiles were selected for comprehensive 3D combined gravity-magnetic modeling. The development of the initial physical-geological models (PGMs) was based on known surface geology, drilling data, previous seismic, magnetotelluric and thermal data analysis, examination of the richest petrophysical data, as well as quantitative and qualitative gravity/magnetic data examination. The PGMs thus reflect the key structural-formational specifics of Azerbaijan’s geological structure, beginning from the subsurface (hundreds of meters) up to the Moho discontinuity (40 - 60 km). The PGMs revealed common factors controlling ore- and hydrocarbon bearing formations, primarily the boundaries of tectonic blocks, masked faults, and buried uplifts of magmatic rocks. Many of these factors can be used to investigate long-term geodynamic activity at a depth. The article summarizes many years of investigation by exemplifying the most typical PGMs for the Greater and Lesser Caucasus, the Kura depression, and central and northern Azerbaijan.

关键词： 3d Gravity-Magnetic Modeling Deep Structure Caucasus Economic Minerals

Evaluation of Simulated CO_2 Concentrations from the CarbonTracker-Asia Model Using In-situ Observations over East Asia for 2009–2013

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Advances in Atmospheric Sciences 2019年第6期36卷 603-613页

作者： Samuel Takele KENEA Young-Suk OH Jae-Sang RHEE Tae-Young GOO Young-Hwa BYUN Shanlan LI lev D.LABZOVSKII Haeyoung LEE Robert F.BANKS Climate Research Division National Institute of Meteorological Sciences Environmental Meteorology Research Division National Institute of Meteorological Sciences Meteorology Department Delta Air LinesInc.

The CarbonTracker(CT) model has been used in previous studies for understanding and predicting the sources, sinks, and dynamics that govern the distribution of atmospheric CO_2 at varying ranges of spatial and temporal scales. However, there are still challenges for reproducing accurate model-simulated CO_2 concentrations close to the surface, typically associated with high spatial heterogeneity and land cover. In the present study, we evaluated the performance of nested-grid CT model simulations of CO_2 based on the CT2016 version through comparison with in-situ observations over East Asia covering the period 2009–13. We selected sites located in coastal, remote, inland, and mountain areas. The results are presented at diurnal and seasonal time periods. At target stations, model agreement with in-situ observations was varied in capturing the diurnal cycle. Overall, biases were less than 6.3 ppm on an all-hourly mean basis, and this was further reduced to a maximum of 4.6 ppm when considering only the daytime. For instance, at Anmyeondo, a small bias was obtained in winter, on the order of 0.2 ppm. The model revealed a diurnal amplitude of CO_2 that was nearly flat in winter at Gosan and Anmyeondo stations, while slightly overestimated in the summertime. The model's performance in reproducing the diurnal cycle remains a challenge and requires improvement. The model showed better agreement with the observations in capturing the seasonal variations of CO_2 during daytime at most sites, with a correlation coefficient ranging from 0.70 to 0.99. Also, model biases were within-0.3 and 1.3 ppm, except for inland stations(7.7 ppm).

关键词： model evaluation in-situ observations CarbonTracker East Asia