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effect of spring grass fires on vegetation patterns and soil quality in abandoned agricultural lands at local and landscape scales in central european Russia

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ecological Processes 2018年第1期7卷 448-466页

作者： Larisa G.Khanina Vadim e.smirnov Michael s.Romanov Maxim V.Bobrovsky Institute of Mathematical Problems of Biology RAs branch of the M.V.Keldysh Institute of Applied Mathematics of the Russian Academy of Sciences1 Prof.Vitkevich StPushchinoMoscow Region 142290Russia center for Forest ecology and Productivity of the Russian Academy of sciences 84/32 bldg.14 Profsoyuznaya StMoscow 117997Russia Institute of Physico-chemical and Biological Problems in soil science of the Russian Academy of sciences 2 Institutskaya StPushchinoMoscow Region 142290Russia

Introduction:Abandonment of agricultural land is often happening all over the world and widespread in *** lands are subject to successional changes in vegetation and it seems necessary to provide effective methods for a sustainable ecosystem management of those ***,factors which determine.s.ccessional processes,especially fires,have not been studied in *** aim of this article is to reveal how spring grass fires affect the abandoned arable lands in the study area at the landscape and local ***:A region of 265.5 km2 located in the south of Moscow was *** the landscape scale,we analyzed the spatial characteristics of the area in relation with a 30-year history of spring fire events extracted from the Landsat archive,and climatic *** regression was *** the local scale,we sampled soil and vegetation at two sites and in three biotopes at each site:mature forest and two neighboring biotopes affected and unaffected by *** species diversity,soil quality,and relationship between soil and vegetation were assessed by ANOVA,v test,NMDs,and ***:Abandoned lands covered 39%of the study area and not less than 72% of these were affected by grass fires,happening mainly between 1998 and *** causes the ignition of the field layer accidentally,but the area over which the fire spreads is determined by climatic factors and the presence of flammable material(dry grass and litter)for *** March temperatures and low precipitation values in April increase the inflammability of dry grasses which are abundant on the former *** a result,burnt areas are steadily expanding in abandoned lands where trees are *** abandoned lands that were either affected or unaffected by fires,two different plant communities developed,respectively:grassy vegetation mainly dominated by calamagrostis epigeios and young forest of pioneer trees with high crown *** all soil variables were statistically diffe

关键词： soil forest landscape

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Using isotope methods to study alpine headwater regions in the Northern caucasus and Tien shan

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Frontiers of earth science 2017年第3期11卷 531-543页

作者： e. ReTs J. cHIZHOVA N. LOsHAKOVA I. TOKAReV M. KIReeVA N. BUDANTseV Yu.K. VAsILcHUK N. FROLOVA V. POPOVNIN P. TOROPOV e. TeRsKAYA A. sMIRNOV e. BeLOZeROV M. KARAsHOVA Water Problems Institute Russian Academy of Sciences ul. Gubkina 3 Moscow 119333 Russia Faculty of Geography Lomonosov Moscow State University Moscow 119991 Russia center for Geo-environmental Research and Modelling (GeOMODeL) at st. Petersburg University St. Petersburg 198504 Russia

High mountain areas provide water resources for a large share of the world＇s population. The ongoing deglaciation of these areas is resulting in great instability of mountainous headwater regions, which could significantly affect water supply and intensify dangerous hydrological processes. The hydrological processes in mountains are still poorly understood due to the complexity of the natural conditions, great spatial variation and a lack of observation. A knowledge of flow-forming processes in alpine areas is essential to predict future possible trends in hydrological conditions and to calculate river runoff characteristics. The goal of this study is to gain detailed field data on various components of natural hydrological processes in the alpine areas of the North caucasus and central Tien shan, and to investigate the possibility that the isotopic method can reveal important regularities of river flow formation in these regions. The study is based on field observations in representative alpine river basins in the North caucasus （the Dzhankuat river basin） and the central Tien shan （the chon-Kyzyl-suu river basin） during 2013-2015. A mixing-model approach was used to conduct river hydrograph separation. Isotope methods were used to estimate the contribution of different nourishment sources in total runoff and its regime. ~80, ~D and mineralization were used as indicators. Two equation systems for the study sites were derived： in terms of water routing and runoff genesis. The Dzhankuat and chon-Kyzyl-suu river hydrographs were separated into 4 components： liquid precipitation/meltwaters, surface routed/subsurface routed waters.

关键词： isotope methods mountain hydrology hydro-graph separation Dzhankuat river chon-Kyzyl-suu river,field data

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Antidiabetic and anti-lipemic effects of cassia siamea leaves extract in streptozotocin induced diabetic rats

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Asian Pacific Journal of Tropical Medicine 2010年第11期3卷 871-873页

作者： s Kumar V Kumar Om Prakash Institute of Pharmaceutical sciences Kurukshetra UniversityKurukshetra -136119HaryanaIndia

Objective:To investigate the antidiabetic and anti-lipemic effects of cassia siamea methanolic leaves ***:The antidiabetic study was performed by measuring blood glucose level with elegance glucometer at weekly intervals i.e.0,7,14 and 21 in normal and streptozotocin induced diabetic *** cholesterol,triglyceride and HDL-cholesterol were determined in normal and streptozotocin induces diabetic rats by *** was used as a reference drug at a dose of 10 mg/***:After the oral administration of extracts at doses of 250 mg/kg and 500 mg/kg for three weeks,blood glucose levels and body weights were significantly improved(Peatment with the extract also resulted in significantly reduction of serum cholesterol and ***-cholesterol level was found to be improved to(Pconclusions:The cassia siamea leaf extract is useful in controlling blood glucose level as well as improving lipid metabolism and body weight in rats with induced diabetes.

关键词： cassia siamea Antidiabetic Anti-lipemic Rat streptozotocin

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elastic and mechanical properties of Mg3Rh intermetallic compound:An ab initio study

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Journal of Magnesium and Alloys 2016年第2期4卷 123-127页

作者： s.Boucetta G.Ugur laboratoire d’elaboration de nouveaux matériaux et caractérisations(enmc) département de physiqueuniversitéferhat abbas setif 1sétif 19000algeria faculty of science department of physicsteknikokullargazi universityankara 06500turkey

In this work, density functional theory plane-wave pseudo potential method, with local density approximation (LDA) and generalized gradientapproximation (GGA) are used to investigate the structural, elastic, mechanical and thermodynamic properties of the intermetallic compoundMg3Rh. comparison of the calculated equilibrium lattice constants and experimental data shows very good agreement. The elastic constants weredetermined from a linear fit of the calculated stress-strain function according to Hooke’s law. From the elastic constants, the bulk modulus B, shearmodulus G, Young’s modulus e, Poisson’s ratio σ, anisotropy factor A, the ratio B/G and the hardness parameter H for Mg3Rh compound areobtained. Our calculated elastic constants indicate that the ground state structure of Mg3Rh is mechanically stable. The calculation results showthat this intermetallic crystal is stiff, elastically anisotropic and ductile material. The sound velocities and Debye temperature are also predictedfrom elastic constants. This is the first quantitative theoretical prediction of these properties.

关键词： Mg3Rh elastic properties Mechanical properties Ab initio

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A method to fabricate small features on scaffolds for tissue engineering via selective laser sintering

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Journal of Biomedical science and engineering 2010年第2期3卷 138-147页

作者： s. Lohfeld M. A. Tyndyk s. cahill N. Flaherty V. Barron P. e. McHugh 不详

Purpose: selective laser sintering (sLs) is a rapid pro- totyping technique applied to produce tissue-engineer- ing scaffolds from powder materials. The standard scanning technique, however, often produces struts of extensive thickness, which means fabrication of high- ly porous scaffolds with small overall dimensions is quite difficult. Nevertheless, this study aims to overcome this shortfall. Design/methodology/approach: To this end, three scanning methods were evaluated in terms of minimum feature size and freedom of design, using a test polyamide (PA) material. Polycaprolactone (PcL) was then employed to create highly porous 3D scaffolds using the preferred scanning me- thod to produce thin struts. Findings: While in normal scanning mode some features were well above the laser spot diameter, strut thicknesses below the laser spot diameter were achieved when using the “outline scan” function for PA material. Those achieved for PcL were slightly higher and in the 500-800 ?m range, with an average pore size of 400 μm. Investigations on the properties of the scaffolds revealed an effective compression modulus of the PcL scaffold of 6.5 MPa. Furthermore, there was no change in physical or che- mical properties when the scaffolds were stored in a physiological environment for 7 weeks. Originality/ value: Though sLs is considered as a fabrication te- chnique for tissue engineering scaffolds, actually pro- duced scaffolds did not comply with porosity requirements and limitations of the sLs process in produ- cing features at the size of the laser beam spot have not been discussed. The present paper shows the capabilities of the sLs process based on two materials and presents a method to minimize feature size in scaffolds.

关键词： selective Laser sintering Rapid Prototyping scaffolds Polycaprolactone Tissue engineering

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effects of Antenna Tilting on Transmitting Power in Mobile cellular communication systems

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International Journal of communications, Network and system sciences 2011年第7期4卷 464-467页

作者： Gbenga e. Aderibigbe Michael O. Kolawole Victor s. A. Adeloye 不详

Radio resources must be wisely managed, in wirele.s.communication systems, when implementing different multiple access techniques. This perspective is pivotal since the variations in propagation channel are very fast and the system is highly complex due to random and unpredictable movement of mobile use.s.continuously. The complexity in the cellular system periodically contributes to different interference levels, high or low, resulting in the degradation of the system capacity. Transmitter power control is an efficient technique to mitigate the effect of interference under fading conditions, combat the Near-Far problem and conserve the battery life. several remedial measures—like space diversity, frequency diversity, route diversity, increase in antenna height, antenna tilting, etc.—have been tried by many operators to overcome the debilitating effect of multipath fading in fixed line-of-sight microwave and mobile communication links. Among these remedial measures, diversity techniques have been extensively studied in terms of improvement factor, whereas the concept of antenna tilting is relatively less explored compared with other remedial measures. In this study, the effect of antenna tilting on fixed and mobile communication links is investigated to find out the optimum tilting angles in terms of design parameters, as well as on quality of service (Qos). The paper established that a deviation of more than 1.5o in antenna elevation angle would impact on Qos requirements and seriously affect the quality of signal to be received by the mobile systems.

关键词： Optimum Tilting Angle Qos Near-Far effect Mobile station carrier-to-Interference Ratio

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Adsorption of Mn^(2+) from aqueous solution using Fe and Mn oxide-coated sand

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Journal of environmental sciences 2013年第7期25卷 1483-1491页

作者： chi-chuan Kan Mannie c Aganon cybelle Morales Futalan Maria Lourdes P Dalida Institute of Hot spring Industry Chia Nan University of Pharmacy and Science environmental engineering Unit University of Philippines Diliman Department of chemical engineering University of Philippines Diliman

The adsorption of Mn2＋ onto immobilized Mn-oxide and Fe-oxide adsorbent such as manganese oxide-coated sand 1 （MOcs1）, manganese oxide-coated sand2 （MOcs2）, iron oxide-coated sand2 （IOcs2）, and manganese and iron oxide-coated sand （MIOcs）was investigated. The effects of pH （5.5 to 8.0） and temperature （25 to45°c） on the equilibrium capacitywere examined. equilibrium studies showed that there is a good fitwith both Freundlich and Langmuir isotherm,which indicates surface heterogeneity and monolayer adsorption of the adsorbents. Kineticdata showed high correlationwith the pseudo second-order model,which signifies a chemisorption-controlled mechanism. The activation energies, activation parameters （ΔG＊,ΔH＊,Δs＊）, and thermodynamic parameters （ΔG0 , ΔH0 , Δs0 ） confirmed that adsorptionwith MIOcswas endothermic and more spontaneous at higher temperaturewhile an opposite trendwas observed for the other adsorbents. Thermodynamic studies showed that adsorption involved formation of activated complex,where MOcs1 and MIOcs follow a physical-chemical mechanism,while MOcs2 and IOcs2 follows purely chemical mechanism.

关键词： activation energy iron oxide kinetics manganese oxide thermodynamics

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Intra-and inter-specific scaling laws of plants and animals

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Acta Mechanica sinica 2021年第2期37卷 321-330页

作者： Jiahang Li Hao Wu Ghassan s。Kassab Wenchang Tan Yunlong Huo Department of Mechanics and engineering science College of EngineeringPeking UniversityBeijing 100871China PKU-HKUsT shenzhen-Hongkong Institution Shenzhen 518057China california Medical Innovations Institute San DiegoCA 92121USA shenzhen Graduate school Peking UniversityShenzhen 518055China Institute of Mechanobiology&Medical engineering School of Life Sciences&BiotechnologyShanghai Jiao Tong UniversityShanghai 200240China

The allometric scaling laws of metabolism in 447 animal and 1200 plant species showed convex and concave curvatures between mass and metabolic rate,*** objective of the study is to explain the difference of curvatures between animals and plants based on fractal *** intraspecific scaling laws were derived from an asymmetric vascular tree with the fractal dimension(i.e.,a in k^(a)_(1)+k^(a)_(2)+…-=1,where k_(i)refers to the ratio of daughter to mother diameters).Based on the intraspecific scaling laws,the allometric scaling exponent of metabolism(i.e.,an interspecific scaling law)was shown to be equal to one-third of fractal ***,a novel piecewise-defined function in conjunction with the intraspecific scaling laws was proposed to explain the diverse metabolic scaling in animals and *** intraspecific and interspecific scaling laws showed good agreement with morphometric *** experimentally-validated scaling models predict the diversity of intraspecific and interspecific scaling seen in *** our knowledge,this is the first study to use fractal models to explain the convex and concave forms of metabolic scaling in animals and *** study resolves the long-term controversies to use the resource-transport network models for explanation of the allometric scaling law of metabolism.

关键词： scaling laws Fractal models Asymmetric tree

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s. e. M. analysis of quartz sand grains from selected Hong Kong and chinese littoral environments

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Acta Oceanologica sinica 1989年第3期8卷 409-422页

作者： A.T.Williams M.c.Thomas coastal Research Unit Department of Science and Chemical Engineering.the Polytechnic of WalesPontypriddMid GlamorganCF37 IDL.UKCoastal Research UnitDepartment of Science and Chemical Engineering.the Polytechnic of WalesPontypriddMid GlamorganCF37 IDL.UK

This pilot study attempts to demonstrate some underlying scanning electron microscopy themes of quartz grain surface textures. A variety of textural patterns and individual features are described for grains selected from various littoral environments. An attempt was made to differentiate samples on surface textures alone, but limitations of using this technique in sedimentological isolation were apparent. statistical analysis of checklist data and photographic evidence revealed some of the more important feature combinations used in environmental diagnosis. The use of discriminant analysis provided quantitative sample separation.

关键词： In analysis of quartz sand grains from selected Hong Kong and chinese littoral environments

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caroli Disease: A case Report Observed at the cocody Teaching Hospital of Abidjan (cote D’Ivoire)

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Open Journal of Gastroenterology 2017年第1期7卷 28-31页

作者： A. Ouattara s. Koné e. Allah-Kouadio D. soro A. W. Ndjitoyap e. Kouadio K. A. Kanga c. D. Fanou M. J. Lohoues-Kouacou B. M. camara service D’Hépato-Gastro entérologie cHU cocody Abidjan C&#244te D’Ivoire service De Pédiatrie Médicale CHU Cocody Abidjan C&#244te D’Ivoire service D’Imagerie Médicale CHU Cocody Abidjan C&#244te D’Ivoire

caroli disease is a rare affection. It’s commonly associated to polycystic kidneys. We report a case of a nine-year-old girl. she was hospitalized at the pediatric unit of the cocody Teaching Hospital for an intermittent fever. During the clinical examination, we found a likely cirrhotic hepatomegaly associated to an edematous-ascitic syndrome. Biological exams showed an infectious syndrome with a hyperleukocytosis at 13.000 per mm3, a hyperneutrophilia at 9.600 per mm3. serological viral markers of B, c and D hepatitis were negative. We saw an intra-hepatic cystic picture at the liver cT-scan with a vascular lesion at his center called a “dot sign”. The diagnosis of caroli disease could be evocated.

关键词： carolisyndrom congenital cystic Dilation cholangitis Liver cT-scan

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