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Functional responses to deforestation in fish communities inhabiting neotropical streams and rivers

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Ecological Processes 2023年第1期12卷 716-732页

作者： Isabel Cantera Céline jézéquel Tony Dejean jérôme Murienne régis Vigouroux Alice Valentini Sébastien Brosse Department of Environmental Science and Policy Universitàdegli Studi di MilanoVia Celoria 2620133 MilanItaly Laboratoire Evolution et DiversitéBiologique UMR5174-UniversitéPaul SabatierCNRSIRD118 Route de Narbonne31062 ToulouseFrance SPYGEN Savoie Technolac-BP 27417 Rue du Lac Saint-André73375 Le Bourget-du-Lac CedexFrance HYDrECO Laboratoire Environnement de Petit SautB.P 82397388 Kourou CedexFrench GuianaFrance

Background Deforestation is a widespread disturbance for neotropical freshwater *** biodiversity declines have been associated with deforestation,its functional consequences for stream and river fish faunas remain poorly *** this study,we explored how deforestation affects the different facets of the functional structure of fish communities inventoried using environmental DNA metabarcoding in 64 river and 35 stream sites of French ***,we investigated how functional richness,divergence,evenness and identity of fish faunas are affected by *** We showed that anthropogenic disturbances in French Guiana are modifying the functional diversity of freshwater fish *** disturbances not only affected the amount of functional traits held by the communities but also the identity of the traits and the internal structure of the functional ***,different facets of the functional diversity supported by fish assemblages were *** streams,deforestation did not affect the overall diversity of traits but reduced functional redundancy,underlined by a shift in functional identity towards assemblages dominated by pelagic *** contrast,river fish faunas experienced a decline in functional richness,paired with shifts in functional identity and a loss of fish species with extreme *** The response to deforestation differed between streams and rivers,but it supports the hypothesis that deforestation is linked to functional changes in fish *** diminishing the range of the functions in rivers or by jeopardizing the redundancy of functions in streams,deforestation could severely hamper the functioning and stability of neotropical freshwater ecosystems.

关键词： eDNA Traits Functional space richness Divergence Evenness Identity Gold mining

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Ameliorative effect of vitamin E on aflatoxin-induced lipid peroxidation in the testis of mice

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Asian journal of Andrology 2001年第3期3卷 217-221页

作者： r.j.Verma Anita Nair Department of Zoology University School of Sciences Guarat University Ahmedabad 380009 IndiaDepartment of Zoology University School of Sciences Guarat University Ahmedabad 380009 India

Aim: To evaluate the ameliorative effect of vitamin E on aflatoxin-induced lipid peroxidation in the testis. Meth-ods: Adult male albino mice were orally administered 25 or 50 μg of aflatoxin in 0.2 mL olive oil per d for 45 *** testis was isolated, blotted free of blood and processed for biochemical analysis. results: There was a dose-de-pendent significantly higher lipid peroxidation in the testis of aflatoxin treated mice than in the controls. The levels ofnon-enzymatic antioxidants such as glutathione, total and reduced ascorbic acid, as well as the activities of enzymaticantioxidants, such as superoxide dismutase, glutathione peroxidase and catalase were significantly lower in the testis ofaflatoxin treated mice. Vitamin E (2 mg/d per animal; orally) pretreatment significantly ameliorates the aflatoxin-in-duced lipid peroxidation which could be due to higher enzymatic and non-enzymatic antioxidants in the testis of mice ascompared with those given aflatoxin alone. Conclusion: Vitamin E pretreatment significantly ameliorates aflatoxin-induced lipid peroxidation in the testis of mice. (Asian j Androl 2001 Sep; 3: 217 - 221)

关键词： aflatoxins vitamin E testis lipid peroxidation

A unified electrical model based on experimental data to describe electrical transport in carbon nanotube-based materials

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Nano research 2020年第6期13卷 1764-1779页

作者： Yoann Dini jérôme Faure-Vincent jean Dijon Univ.Grenoble-Alpes CEALITENDTNMF-38000GrenobleFrance Univ.Grenoble-Alpes CEACNRSIRIGSyMMESF-38000GrenobleFrance

Understanding the electrical transport in carbon nanotube(CNT)materials is one key to reach very high electrical *** CNT material resistivity(ρ(T))as function of the temperature are fully apprehended by their reduced activation W(T)=dln(ρ)/dln(T)*** to now,no model accurately fits W(T)curves,thus preventing from precisely describing the CNT material electrical *** present a new electrical transport model that perfectly fits all W(T)curves found in the literature and in our own *** material resistivities are modeled byρ(T)=ρ0(T^−α+M(1+βTγT^2)).Our model has few enough parameters(α,M,β,γ)to relate them to the CNT *** 70 K,we experimentally show that CNT material resistivity follows the Luttinger Liquid theory justifying the T^−αterm in our *** 70 K,the polynomial part becomes dominant and depends on the two different CNT fabrication techniques which lead to two very different yarn *** yarns made from floating catalyst chemical vapor deposition CNTs,the polynomial is explained by the percolation of metallic CNT ***,the polynomial of yarns spun from CNT arrays is explained by the electrical transport in CNT bundles which are the basic building blocks of this type of yarns.

关键词： carbon nanotube carbon-based materials electrical conductivity electrical transport model Luttinger Liquid

Generalizing plant–water relations to landscapes

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journal of Plant Ecology 2011年第1期4卷 101-113页

作者： r.H.Waring j.j.Landsberg College of Forestry Oregon State UniversityCorvallisOR 97331USA Withycombe Church LaneMt WilsonNSW 2786Australia

Aims Changing climate and land use patterns make it increasingly important that the hydrology of catchments and ecosystems can be reliably *** aim of this paper is to identify the biophysical factors that determine the rates of water vapor loss from different types of vegetation,and to seek,from an array of currently available satelliteborne sensors,those that might be used to initialize and drive landscape-level hydrologic *** Findings Spatial variation in the mean heights,crowd widths,and leaf area indices(LAI)of plant communities are important structural variables that affect the hydrology of *** stomatal conductance(G)imposes physiological limitation on transpiration by *** maximum value of G(Gmax)is closely linked to canopy photosynthetic capacity,which can be estimated via remote sensing of foliar chlorophyll or nitrogen *** be modeled as a nonlinear multipliable function of:(i)leaf–air vapor pressure deficit,(ii)water potential gradient between soil and leaves,(iii)photosynthetically active radiation absorbed by the canopy,(iv)plant nutrition,(v)temperature and(vi)the CO_(2) concentration of the *** surveys with Light Detection and ranging(LiDAr)and interferometric rADAr,along with high-resolution spectral coverage in the visible,near-infrared,and thermal infrared bands,provide,along with meteorological data gathered from weather satellites,the kind of information required to model seasonal and interannual variation in transpiration and evaporation from landscapes with diverse and dynamic vegetation.

关键词： canopy stomatal conductance plant water relations process-based models remote sensing

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Chinese Annals of Mathematics,Series B 2002年第2期23卷 187-204页

作者： E.j.DEAN r.GLOWINSKI DepartmentofMathematicsUniversitofHouston Departmentof MathematicsUniversity of Houston 651 P.G.HoffmanHallHoustonTX 77204-3008US

This article discusses computational methods for the numerical simulation of unsteady Bingham visco-plastic flow. These methods are based on time-discretization by operator-splitting and take advantage of a characterization of the solutions involving some kind of Lagrange multipliers. The full discretization is achieved by combining the above operator-splitting methods with finite element approximations, the advection being treated by a wave-like equation 'equivalent' formulation easier to implement than the method of characteristics or high order upwinding methods. The authors illustrate the methodology discussed in this article with the results of numerical experiments concerning the simulation of wall driven cavity Bingham flow in two dimensions.

关键词： Bingham visco-plastic flow Operator-splitting methods Finite element

Analysis and Modeling of Slope Stability in the Three-Gorges Dam reservoir (China)——The Case of Huangtupo Landslide

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journal of Mountain Science 2011年第2期8卷 166-175页

作者： r.COjEAN Y.j.CA Centre de Géosciences Mines-ParisTech Paris France Changjiang Institute of Survey Planning Design & Research CWRC Wuhan China

The water level in the Three Gorges Dam reservoir is expected to change between the elevations of 145 m and 175 m, as a function of the flood control implementation and the intensity of the annual flood. As a matter of fact, the hydraulical and mechanical loadings, related to the water level modifications, will result in alterations in the slope stability conditions. The town of Badong (Hubei), of 20 000 inhabitants, is one of the towns which was submerged by the impoundment of the reservoir. As a consequence, the new town of Badong was constructed on a nearby site which appeared to be partly an unstable site. A part of this site corresponds to an old landslide, the Huangtupo landslide, the base of which had to be submerged by the water of the reservoir. The analysis of the Huangtupo landslide, taking into account various events scenarios, drainage and reinforcement measures and monitoring devices, allows to illustrate the general process implemented all along the reservoir in order to mitigate the landslide hazard.

关键词： Three Gorges Dam Landslide Modelling

Spatial Estimation of Saturated Hydraulic Conductivity from Terrain Attributes Using regression,Kriging,and Artificial Neural Networks

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Pedosphere 2011年第2期21卷 170-177页

作者： H.r.MOTAGHIAN j.MOHAMMADI Department of Soil Science Agriculture CollegeShahrekord UniversityShahrekord (Iran)

Several methods,including stepwise regression,ordinary kriging,cokriging,kriging with external drift,kriging with varying local means,regression-kriging,ordinary artificial neural networks,and kriging combined with artificial neural networks,were compared to predict spatial variation of saturated hydraulic conductivity from environmental *** methods except ordinary kriging allow for inclusion of secondary *** secondary spatial information used was terrain attributes including elevation,slope gradient,slope aspect,profile curvature and contour curvature.A multiple jackknifing procedure was used as a validation *** mean square error (rMSE) and mean absolute error (MAE) were used as the validation indices,with the mean rMSE and mean MAE used to judge the prediction *** performance by ordinary kriging was poor,indicating that prediction of saturated hydraulic conductivity can be improved by incorporating ancillary data such as terrain *** combined with artificial neural networks performed *** prediction models made better use of ancillary information in predicting saturated hydraulic conductivity compared with the competing *** combination of geostatistical predictors with neural computing techniques offers more capability for incorporating ancillary information in predictive soil *** is great potential for further research and development of hybrid methods for digital soil mapping.

关键词： digital elevation model geostatistics soil hydraulic properties spatial mapping

Distinct dendritic α phase emerging on the surface of primary α phase in a compressed near-α titanium alloy

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journal of Materials Science & Technology 2018年第4期34卷 666-669页

作者： Z.Liu Z.B.Zhao j.r.Liu Q.j.Wang r.Yang Institute of Metal research Chinese Academy of Sciences School of Materials Science and Engineering University of Science and Technology of China

The characteristic of the surface morphology of primary α phase was studied in a deformed near-α tita- nium alloy. Dendritic α phase emerged on the surfaces of primary α phase when the alloy was air-cooled in α ＋β phase field after deformation. The dendritic α grain has the same orientation with its original primary α grain. The formation of the dendritic α phase could be explained by interface instability in epi- taxial growth process of the primary α phase. The dislocations induced by deformation could facilitate the formation of dendritic α phase leading to the dendritic α phase and more obvious with the increase of strain. The growth of dendritic α phase was finally limited by the nucleation of second α phase with cooling.

关键词： Epitaxial growth Dendritic α phase Microstructure Interface instability Hot deformation

A numerical optimization of high altitude testing facility for wind tunnel experiments

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Chinese journal of Aeronautics 2015年第3期28卷 636-648页

作者： j.Bruce ralphin rose G.r.jinu C.j.Brindha Department of Aeronautical Engineering Regional Centre of Anna University Department of Mechanical Engineering University College of EngineeringNagercoil Department of Aeronautical Engineering The Raajas Engineering College

Abstract High altitude test facilities are required to test the high area ratio nozzles operating at the upper stages of rocket in the nozzle full flow conditions. It is typically achieved by creating the ambient pressure equal or less than the nozzle exit pressure. On average, air/GN2 is used as active gas for ejector system that is stored in the high pressure cylinders. The wind tunnel facilities are used for conducting aerodynamic simulation experiments at/under various flow velocities and operating conditions. However, constructing both of these facilities require more laboratory space and expensive instruments. Because of this demerit, a novel scheme is implemented for conducting wind tunnel experiments by using the existing infrastructure available in the high altitude testing （HAT） facility. This article presents the details about the methods implemented for suitably modifying the sub-scale HAT facility to conduct wind tunnel experiments. Hence, the design of nozzle for required area ratio A/A＊, realization of test section and the optimized configuration are focused in the present analysis. Specific insights into various rocket models including high thrust cryogenic engines and their holding mechanisms to conduct wind tunnel experiments in the HAT facility are analyzed. A detailed CFD analysis is done to propose this conversion without affecting the existing functional requirements of the HAT facility.

关键词： CFD Enclosed free-jet section Ground testing High altitude testing (HAT)facility Optimization