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Presence–absence surveys of prey and their use in predicting leopard (Panthera pardus) densities: a case study from Armenia

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Integrative Zoology 2008年第4期3卷 322-332页

作者： igor G.KHOROZYAN Alexander G.MALKHASYAN Alexei v.ABRAMOv Zoological Institute Russian Academy of SciencesSt PetersburgRussia Ministry of Nature Protection of the Republic of Armenia YerevanArmenia

It is important to predict how many individuals of a predator species can survive in a given area on the basis of prey sufficiency and to compare predictive estimates with actual numbers to understand whether or not key threats are related to prey *** terrain and low detection probabilities do not allow for the use of traditional prey count techniques in mountain *** used presence–absence occupancy modeling and camera-trapping to estimate the abundance and densities of prey species and regression analysis to predict leopard(Panthera pardus)densities from estimated prey biomass in the mountains of the Nuvadi area,Meghri Ridge,southern *** prey densities were 12.94±2.18 individuals km–2 for the bezoar goat(Capra aegagrus),6.88±1.56 for the wild boar(Sus scrofa)and 0.44±0.20 for the roe deer(Capreolus capreolus).The detection probability of the prey was a strong function of the activity patterns,and was highest in diurnal bezoar goats(0.59±0.09).Based on robust regression,the estimated total ungulate prey biomass(720.37±142.72 kg km–2)can support a leopard density of 7.18±3.06 individuals 100 km–*** actual leopard density is only 0.34 individuals 100 km–2(*** subadult male recorded over the 296.9 km2),estimated from tracking and *** most plausible explanation for this discrepancy between predicted and actual leopard density is that poaching and disturbance caused by livestock breeding,plant gathering,deforestation and human-induced wild fires are affecting the leopard population in Armenia.

关键词： Armenia leopard linear regression presence–absence prey.

Predictors of visual outcome in eyes with choroidal neovascularization secondary to age related macular degeneration treated with intravitreal bevacizumab monotherapy

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International Journal of Ophthalmology(English edition) 2013年第1期6卷 62-66页

作者： Jay Chhablani Jae SukKim William R Freeman igor Kozak Hai-Yan Wang Lingyun Cheng Jacob's Retina Center at Shiley Eye Center University of California L v Prasad Eye Institute Department of Ophthalmology Sanggye Paik Hospital Inje University

AIM:To evaluate the predictors of visual improvement in eyes with naive choroidal neovascularization secondary to age-related macular degeneration (CNv -AMD) treated with intravitreal bevacizumab (IvB) monotherapy. METHODS:Fifty eyes with naive CNv-AMD with pretreatment best-corrected visual acuity (BCvA) better than 20/200 and treated with IvB monotherapy were evaluated. Several variables including age, sex, pre-treatment BCvA, CNv type and lesion size on fluorescein angiogram as well as SD-OCT parameters including pre-treatment central macular thickness (CMT), inner-segment/outer-segment (IS/OS) junction integrity, and external limiting membrane (ELM) integrity were analyzed to predict visual ***:On univariate regression, pretreatment ELM damage was associated with less visual improvement after treatment (P =0.0145). However, ELM damage predicted only 10% of the visual outcome. On multivariate regression, pretreatment BCvA, IS/OS junction, and ELM integrity on SD-OCT were the significant predictors for the treatment effect and together predicted 37% of visual improvement. CONCLUSION:Pretreatment BCvA, ELM and IS/OS junction integrity on SD-OCT are of significant value inpredicting the visual improvement in naive wet AMD patients treated with IvB monotherapy.

关键词： external limiting membrane age-related macular degeneration choroidal neovascularization avastin

Improving the performance of LOX/kerosene upper stage rocket engines

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Propulsion and Power Research 2017年第3期6卷 157-176页

作者： igor N.Nikischenko Raymond D.Wright Roman A.Marchan Firefly Europe B.v. Blaricum 1261 GAThe Netherlands Spacefleet Ltd DevizesWiltshireSN103APUnited Kingdom

Improved liquid rocket engine cycles were proposed and analyzed via comparison with existing staged combustion and gas-generator *** key features of the proposed cycles are regenerative cooling of thrust chamber by oxygen and subsequent use of this oxygen for driving one or two oxygen *** fuel pump(s)are driven in a conventional manner,for example,using a fuel-rich gas-generator *** with staged combustion cycle based on oxygen-rich pre-burner showed that one of the proposed semi-expander cycles has a specific impulse only on 0.4%lower while providing much lower oxygen temperature,more efficient tank pressurizing system and built-in roll *** semi-expander cycle can be considered as a more reliable and cost-effective alternative of staged combustion *** semi-expander cycle can be considered as an improvement of gas-generator *** proposed semi-expander cycles were developed as a derivative of thrust chamber regenerative cooling performed by *** of existing oxygen/kerosene engines showed that replacing of kerosene regenerative cooling with oxygen allows a significant increase of achievable specific impulse,via optimization of mixture *** is especially the case for upper stage *** increasing of propellants average density can be considered as an additional benefit of mixture ratio *** was demonstrated that oxygen regenerative cooling of thrust chamber is a feasible and the most promising option for oxygen/kerosene *** of oxygen regenerative cooling and semi-expander cycles potentially allows creating the oxygen/kerosene propulsion systems with minimum specific impulse *** is important that such propulsion systems can be fully based on inherited and well-proven technical solutions.A hypothetic upper stage engine with thrust 19.6 kN was chosen as a prospective candidate for theoretical analysis of the proposed semi-expander *** newly-developed software RECS

关键词： Oxygen Kerosene Liquid rocket engine Upper stage

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高氯酸杂环配合物金属盐的激光起爆(英文)

含能材料 2006年第6期14卷 401-405页

作者： Mikhail A.Ilyushin igor v.Tselinsky Irina v.Bachurina Emil Ya.Seidov Anatolii S.Kozlov Dmitrii v.Korolev Alexei E.Olenin Saint-Petersburg State Institute of Technology (Technical University) Russia

Several d-metal perchlorate complexes with 3-hydrazino-4-amino-5-R-1,2,4-triazoles as ligands （where R=H, CH3, SH） were investigated. It was shown that SH-group inhibited radical processes of thermal decomposition and burning of the complexes and also increased the thresholds of their Q-switch IR-laser initiation compared with the salts where as R=H, CH3-groups decreased the sensitivity of the metal complexes to laser initiation.

关键词：物理化学爆炸物脉冲激光技术

Isothianaphthene diimide: an air-stable n-type semiconductor

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Science China Chemistry 2019年第10期62卷 1360-1364页

作者： Xiaolong Chen Yaowu He Muhammad Umair Ali Yu He Yanan Zhu Aiyuan Li Changbin Zhao igor FPerepichka Hong Meng School of Advanced Materials Peking University Shenzhen Graduated SchoolShenzhen 518055China Department of Materials Science and Engineering College of EngineeringPeking UniversityBeijing 100871China Shaanxi Institute of Flexible Electronics Northwestern Polytechnical UniversityXi’an 710072China

Herein,we propose a new strategy to develop air-stable n-type organic semiconductors with non-classical thiophene aromatic diimide derivatives by replacing aromatic naphthalene with a heteroaromatic isothianaphthene *** designed and successfully synthesized the isothianaphthene core based diimide material,N,N′-bis(n-hexyl)isothianaphthene-2,3,6,7-tetracarboxylic acid diimide(BTDI-C6)as an n-type *** to N,N′-bis(n-hexyl)naphthalene-1,4,5,8-tetracarboxylic acid diimide(NDI-C6),BTDI-C6 possesses a deeper LUMO energy level of-4.21 ev,which is 0.32 ev lower than that of *** molecular modelling and experimental results elucidated that organic thin film transistors(OTFTs)based on both of these materials exhibit comparable mobilities;however,the threshold voltage of BTDI-C6 based device(+7.5 v)is significantly lower than that of NDI-C6 based counterpart(+34v).Moreover,the low-lying LUMO energy level of BTDI-C6 ensures excellent air-stability which is further validated by the device *** addition,BTDI-C6 shows high luminescence while NDI-C6 is not luminescent at all in solution,which reveals the potential application of our newly synthesized material in n-type light-emitting transistors.

关键词： isothianaphthene non-classical imide n-type

variations of Geomagnetic Response Functions before the 2011 Tohoku Earthquake

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Open Journal of Earthquake Research 2019年第2期8卷 70-84页

作者： igor I. Rokityansky valeriia I. Babak Artem v. Terehyns Masashi Hayakawa Subbotin Institute of Geophysics Ukrainian National Academy of Sciences Kiev Ukraine UEC Alliance Center #521 Hayakawa Institute of Seismo Electromagnetics Co. Ltd. (Hi-SEM) Chofu Japan Advanced & Wireless Communications Research Center University of Electro-Communications (UEC) Chofu Japan

Induction vectors have been extensively calculated using data from 19 Japanese observatories for a dozen years preceding the huge 2011 Tohoku earthquake (EQ). At 6 observatories anomalous variations of induction vectors were separated in the years of 2008-2010 that can be identified as middle-term precursors. These observatories are located not at the shortest distance from the EQ epicenter, that is in agreement with the widely known phenomenon of spatial selectivity of EQ precursors. The analysis of horizontal tensors reveals a conductivity anomaly under the central part of the Boso peninsula (at 30 km from Tokyo) with a WNW-ESE strike coinciding both with the Sagami trough strike and the strike of well conducting 3 km thick sediments. A joint analysis of geoelectric and tectonic data leads to a preliminary conclusion that the Boso conductivity anomaly connects two large scale conductors: Pacific sea water and a deep magma reservoir beneath a volcanic belt. Between two so different conductors an unstable transition zone can be expected which should be sensitive to changes of stress. Applying our original processing including two steps analysis and elimination of annual and monthly periods, a short-term two-month-long precursor of bay-like form was successfully separated at the observatory of Kanozan, KNZ (over the Boso anomaly) despite its strong noise. All the results were obtained with advanced multi-windows multi-rr (remote reference) robust programs with a coherency control. Dependence of the results of induction vector calculation on geomagnetic activity was carefully studied, and this dependence is relatively strong when the magnetotelluric field and noise have approximately the same magnitude. But even in this case we could identify the precursor field.

关键词： Response Function Induction vector Conductivity Structure Electromagnetic EQ Precursor

高强韧Ti-3Al-5Mo-4Cr-2Zr-1Fe合金低周疲劳性能研究

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稀有金属材料与工程 2021年第2期50卷 588-594页

作者：张航孙洋洋 igor.v.Alexandrov 方志刚易承杰董月成常辉周廉南京工业大学材料科学与工程学院/新材料研究院江苏南京211800 江苏先进无机功能复合材料协同创新中心江苏南京211899 乌法国立航空技术大学俄罗斯乌法450008 中国人民解放军92228部队北京100072 南京工业大学2011学院江苏南京211800

通过室温下应变控制疲劳试验研究了高强韧Ti-3Al-5Mo-4Cr-2Zr-1Fe合金的低周疲劳性能。结果表明:在高应变幅值下(Δεt/2=1.0%,1.2%,1.4%,1.6%),合金的循环应力响应表现为初始循环软化,而后趋于循环稳定;在低应变幅值下(Δεt/2=0.6%,0.... 详细信息

通过室温下应变控制疲劳试验研究了高强韧Ti-3Al-5Mo-4Cr-2Zr-1Fe合金的低周疲劳性能。结果表明:在高应变幅值下(Δεt/2=1.0%,1.2%,1.4%,1.6%),合金的循环应力响应表现为初始循环软化,而后趋于循环稳定;在低应变幅值下(Δεt/2=0.6%,0.8%),合金的循环应力响应表现为循环饱和特征。断口形貌观察发现:应变幅值为0.6%时,疲劳裂纹源只有一处,在断口表面分布有大量细小的二次裂纹。当应变幅增加到1.6%时,组织中发现多处疲劳裂纹源,二次裂纹的数量明显减少,但长度和宽度明显增加。透射电镜结果表明:在低应变幅值下(Δεt/2=0.6%),在αp/β界面处出现大量的位错堆积,在此处易产生应力集中导致微裂纹形核。而在高应变幅值下(Δεt/2=1.6%),在αp相中有明显的变形不均匀性,在αp相内出现大量的位错缠结和位错碎片,并且在αs相中出现一些位错塞积,但在β基体中没有明显的位错堆积情况。由于长条αp相的存在,能够提升α相和β相变形的相容性,延缓疲劳裂纹形核和扩展,因此使Ti-35421合金有着优异的低周疲劳性能。

关键词：低成本钛合金低周疲劳循环软化循环稳定

Wave Processes and Mass Transfer on the Copper-Stainless Steel Interface under Solid Phase Bonding by High-Temperature Rolling

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Open Journal of Metal 2018年第4期8卷 67-74页

作者： Boris v. Borts Aleksander A. Parkhomenko igor O. vorobyov Alexander A. Lopata National Science Center Kharkov Institute of Physics & Technology Kharkov Ukraine

The paper presents the study of hierarchy of deformation wave-processes from nano- to macro-structural level, which takes place in dissimilar materials, bonded by high-temperature vacuum rolling in solid phase. The focus was on the processes that occur on the interface of the bonded materials: mass trasfer of impurities and alloying elements stimulated by deformation, the study of nano- and micro-hardness.

关键词： vacuum Hot Rolling Solid Phase Interface Cupper-Stainless Steel Microscopy Micro-Hardness Nano-Hardness Wave Processes Scaling

Bioactive properties of glycosaminoglycans extracted from Turkey (Meleagris gallopavo) by-products

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Food Bioscience 2022年第2期46卷 321-329页

作者： Evellin Balbinot-Alfaro Claudio R.Novello Elisˆangela Düsman Alexandre T.Alfaro Helyn P.O.Barddal igor v.Almeida veronica E.P.vicentini vil´asia G.Martins School of Chemistry and Food Federal University of Rio GrandeRio GrandeRSBrazil Department of Food Technology Federal University of TechnologyParan´aFrancisco Beltr˜aoPRBrazil Department of Biochemistry and Molecular Biology Federal University of Paran´aCuritibaPRBrazil Federal Rural University of Amazonia Capit˜ao PoçoPABrazil Department of Biotechnology State University of Maring´aMaring´aPRBrazil

Turkey wattle is a by-product generated during slaughter,which has a large amount of connective tissue and is a potential source of glycosaminoglycans(GAGs).This study aimed to extract GAGs from the turkey wattle(Meleagris gallopavos)and investigate its anticoagulant activity,and its cytotoxic and antiproliferative activity in tumor *** sulfate(CS-4 and CS-6)and dermatan sulfate(DS)present in the F-vII fraction and hyaluronic acid(HA)in the F-v fraction were *** HA showed a high molecular weight(1.0×10^(6) Da)and an apparent cytotoxic/antiproliferative effect against human hepatoma cells.F-vII fraction has an apparent cytotoxic/antiproliferative effect against renal adenoma cells and anticoagulant potential in *** results achieved in this study demonstrated that wattle,a by-product of turkey industrialization,has the potential to be valued as a raw material for the extraction of GAGs with bioactive properties.

关键词： Poultry By-products Hyaluronic acid Dermatan sulfate Chondroitin sulfate