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Environmental and biological factors affecting the abundance of Prosopis flexuosa saplings in the central-west monte of Argentina

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forest Ecosystems 2022年第1期9卷 103-110页

作者： cappa f.m. Campos V.E. Barri f.R. Ramos L. Campos C.m. INTERBIODES(Interacciones Biologicas del Desierto) Facultad Ciencias ExactasFísicas y Naturales(Universidad Nacional de San Juan)San JuanArgentina CIGEOBIO-CONICET(Centro de Investigaciones de la Geosfera y Biosfera Consejo Nacional de Investigaciones Científicas y Tecnicas)San JuanArgentina Instituto de Diversidad y Ecología Animal CONICET–UNCCordobaArgentina IADIZA Instituto Argentino de Investigaciones de las Zonas AridasUniversidad Nacional de CuyoGobierno de MendozaCONICETMendozaArgentina

Background:Trees and forests in drylands help mitigate the challenges through provision of economic products and vital environmental services such as habitat for biodiversity,prevention of erosion and desertification,regulation of water,microclimate,and soil *** condition and changes in dry forests can be assessed by using ecological indicators able to quantify spatial and temporal changes in *** of the ways to determine the condition of the forest is to study the dominant tree species and its *** study aimed to assess whether the abundance of Prosopis flexuosa saplings is affected by environmental and biological ***:To evaluate the first variables we used data from remote sensing such as satellite images and Aster Global Digital model(GDEm).The second set of variables was about exotic and native ungulates and we used feces of these animals and camera traps to take *** found that sapling abundance related positively to sandy substrates and negatively to Wetness *** the other hand,in relation to biological variables,the abundance of saplings was positively affected by density of adult trees and by number of seeds dispersed by equines,but space use by Lama guanicoe had a negative relationship with *** research shows that *** saplings are benefited from sandy substrates and the conditions around adult *** addition to this,we found that exotic ungulates in low densities have neutral(***)or positive(***)effects on sapling ***:Based on these findings,we conclude that regeneration of the population of *** in our study area has no major *** addition,we corroborated that the presence of exotic and domestic ungulates in low densities does not have deleterious consequences for saplings of the dominant tree,***.

关键词： Bos primigenius taurus Dry forests Equines Exotic and domestic ungulates Lama guanicoe Prosopis flexuosa Remote sensing Saplings Seed dispersal

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Infrared, Diffuse Reflectance and Dielectric Studies ofAntimony Trisulphide

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Journal of.m.terials Science & Technology 1998年第4期14卷 344-348页

作者： Hanafi, Z.m. Ismail, f.m. Khalil, m.Sh. Inorganic Chemistry Dept. National Research Centre Dokki Cairo Egypt

Infrared absorption spectra of orange, black and transferred Sb//2S//3 samples have been studied in the spectral range 200-4000 cm** minus **1. The pronounced difference between the different samples is the appearance of excess sulphur present in the orange and transferred samples except those of transferred at 543 K and the black Sb//2S//3. The change of sharpness of some IR peaks reveals the amorphous/crystalline change. The effect of the degree of crystallinity and stoichiometry on the energy gap values was investigated by using optical method. The obtained dielectric parameters epsilon prime and epsilon double prime of the different samples are thoroughly affected by the degree of crystallinity and smoothly affected by either the frequency or the temperature or both, except at lower frequencies. (Edited author abstract) 26 Refs.

关键词： Antimony compounds

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Darcy-forchheimer flow of variable conductivity Jeffrey liquid with Cattaneo-Christov heat flux theory

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Applied mathematics and mechanics(English Edition) 2017年第4期38卷 557-566页

作者： m. A. mERAJ S.A. SHEHZAD T. HAYAT f.m. ABBASI A. ALSAEDI Department of.m.thematics COMSATS Institute of Information TechnologySahiwal 57000Pakistan Department of.m.thematics Quaid-i-Azam UniversityIslamabad 44000Pakistan NAAm Research Group Department of MathematicsFaculty of ScienceKing Abdulaziz UniversityJeddah 21589Saudi Arabia Department of.m.thematics COMSATS Institute of Information TechnologyIslamabad 44000Pakistan

The role of the Cattaneo-Christov heat flux theory in the two-dimensional laminar flow of the Jeffrey liquid is discussed with a vertical sheet. The salient feature in the energy equation is accounted due to the implementation of the Cattaneo-Christov heat flux. A liquid with variable thermal conductivity is considered in the Darcy-forchheimer porous space. The mathematical expressions of.m.mentum and energy are coupled due to the presence of.m.xed convection. A highly nonlinear coupled system of equations is tackled with the homotopic algorithm. The convergence of the homotopy expressions is calculated graphically and numerically. The solutions of the velocity and temperature are expressed for various values of the Deborah number, the ratio of the relaxation time to the retardation time, the porosity parameter, the mixed convective parameter, the Darcy-forchheimer parameter, and the conductivity parameter. The results show that the velocity and temperature are higher in fourier＇s law of heat conduction cases in comparison with the Cattaneo-Christov heat flux model.

关键词： Darcy-forchheimer porous medium variable conductivity Jeffrey liquid Cattaneo-Christov heat flux

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Boundary-layer non-Newtonian flow over vertical plate in porous medium saturated with nanofluid

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Applied mathematics and mechanics(English Edition) 2011年第12期32卷 1577-1586页

作者： f.m. HADY f. S. IBRAHIm S. m. ABDEL-GAIED m. R. EID Department of.m.thematics Faculty of Science Assiut University Assiut 71516 Egypt Department of Science and mathematics Faculty of Education Assiut University The New Valley 72111 Egypt

The free convective heat transfer to the power-law non-Newtonian flow from a vertical plate in a porous medium saturated with nanofluid under laminar conditions is investigated. It is considered that the non-Newtonian nanofluid obeys the mathematical model of power-law. The model used for the nanofluid incorporates the effects of Brown- ian motion and thermophoresis. The partial differential system governing the problem is transformed into an ordinary system via a usual similarity transformation. The numer- ical solutions of the resulting ordinary system are obtained. These solutions depend on the power-law index n, Lewis number Le, buoyancy-ratio number Nr, Brownian motion number Nb, and thermophoresis number Nt. for various values of n and Le, the effects of the influence parameters on the fluid behavior as well as the reduced Nusselt number are presented and discussed.

关键词： non-Newtonian free convection nanofluid porous media

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missense mutations of the fibrillin-1 gene in two Chinese patients with severe marfan syndrome

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Chinese medical Journal 2001年第5期114卷 25-28页

作者： Ivan f.m. LO, Rosanna m.S. WONG, fanny W.f. LAm, Tony m.f. TONG and Stephen T.S. LAm Clinical Genetic Service Department of Health 3/F Cheung Sha Wan Jockey Club Clinic 2 Kwong Lee Road Shamshuipo Kowloon Hong Kong Special Administrative Region China. akyblue@***

Objective To describe two Chinese patients with severe forms of.m.rfan syndrome and to report findings of.m.tational analysis of the fibrillin-1 (fBN1) *** Two Chinese patients were studied, one suffering from marfan syndrome of infantile onset and the other of neonatal onset. Their clinical features were described. mutational analysis of the fBN1 gene was performed using polymerase chain reaction (PCR) technique and direct sequencing of exons 23 - 32,where the mutational hotspots for severe forms of.m.rfan syndrome are *** Two missense mutations were successfully identified, a G3037A transition and an A3083T transversion, the latter being an unreported *** Taking advantage of the clustering phenomenon of.m.tations in severe forms of.m.rfan syndrome, one can identify fBN1 mutations in these patients by first screening the mutational hotspots,thus reducing the effort that would otherwise be much greater because of the size of the gene.

关键词： marfan syndrome fibrillin-1 mutation

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Complement-dependent neuroinflammation in spinal cord injury:from pathology to therapeutic implications

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Neural Regeneration Research 2025年第5期20卷 1324-1335页

作者： Hassan Saad Bachar El Baba Ali Tfaily firas Kobeissy Juanmarco Gutierrez Gonzalez Daniel Refai Gerald R.Rodts Christian mustroph David Gimbel Jonathan Grossberg Daniel L.Barrow matthew f.Gary Ali m.Alawieh Department of Neurosurgery Emory University School of MedicineAtlantaGAUSA Department of Neurology Yale UniversityNew HavenCTUSA Center for Neurotrauma Multiomics&Biomarkers(CNMB)Morehouse School of MedicineAtlantaGAUSA

Spinal cord injury remains a major cause of disability in young adults,and beyond acute decompression and rehabilitation,there are no pharmacological treatments to limit the progression of injury and optimize recovery in this *** the thorough investigation of the complement system in triggering and propagating cerebral neuroinflammation,a similar role for complement in spinal neuroinflammation is a focus of ongoing *** this work,we survey the current literature investigating the role of complement in spinal cord injury including the sources of complement proteins,triggers of complement activation,and role of effector functions in the *** study relevant data demonstrating the different triggers of complement activation after spinal cord injury including direct binding to cellular debris,and or activation via antibody binding to damage-associated molecular *** effector functions of complement have been implicated in spinal cord injury,and we critically evaluate recent studies on the dual role of complement anaphylatoxins in spinal cord injury while emphasizing the lack of pathophysiological understanding of the role of opsonins in spinal cord *** this pathophysiological review,we systematically review the different translational approaches used in preclinical models of spinal cord injury and discuss the challenges for future translation into human *** review emphasizes the need for future studies to dissect the roles of different complement pathways in the pathology of spinal cord injury,to evaluate the phases of involvement of opsonins and anaphylatoxins,and to study the role of complement in white matter degeneration and regeneration using translational strategies to supplement genetic models.

关键词： complement neuroinflammation neuroplasticity regeneration spinal cord injury targeted therapy

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Study of phase separation in Ga25Se75-xTex chalcogenide thin films

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Progress in Natural Science:materials International 2013年第2期23卷 139-144页

作者： f.A. Al-Agel E.A. Al-Arfaj f.m. Al-marzouki Shamshad A. Khan A.A. Al-Ghamdi Department of Physics King Abdulaziz University Department of Physics College of Applied Sciences Umm Al-Qura University Department of Physics St. Andrew's College

The effects of composition and thermal annealing in between glass transition and crystallization temperature on the optical and structural properties of Ga25Se75-xTex were investigated. The glass transition and crystallization temperature of the synthesized samples was measured by non-isothermal DSC measurements. Amorphous thin films of Ga25Se75-xTex glasses were grown onto ultra clean glass/Si wafer (100) substrates using the vacuum evaporation technique. The effect of thermal annealing on the optical gap (Eg) for Ga25Se75-xTex thin films in the temperature range 358-388K is studied. As-prepared and annealed thin films were characterized by X-ray diffraction, field emission scanning electron microscopy, energy dispersive X-ray spectroscopy and optical absorption. Thermal annealing was found to be accompanied by structural effects, which in turn, lead to changes in the optical constants. The optical absorption coefficient (a) for as-deposited and thermally annealed films was calculated from the absorbance data. from the knowledge of absorption coefficient at different wavelengths, the optical band gap (Eg) was calculated for all compositions of Ga25Se75-xTex thin films before and after thermal annealing. Results indicate that allowed indirect optical transition is predominated in as-deposited and thermally annealed thin films. The influence of Te incorporation and thermal annealing in Ga25Se75-xTex thin films results in a gradual decrease in the indirect optical gap, this behaviorcan be explained as increased tailing. The decrease in optical band gap and an increase in absorption coefficient and extinction coefficient with thermal annealing can be attributed to transformation from amorphous to crystalline phase.

关键词： Thin films Laser-irradiation Crystallization Phase change Optical band gap

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Nonlinear three-dimensional stretched flow of an Oldroyd-B fluid with convective condition, thermal radiation, and mixed convection

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Applied mathematics and mechanics(English Edition) 2017年第7期38卷 969-980页

作者： B. mAHANTHESH B. J. GIREESHA S.A. SHEHZAD f.m. ABBASI R. S. R. GORLA Department of.m.thematics Christ University Bangalore 560029 Karnataka India Department of Studies and Research in mathematics Kuvempu University Shankarghatta 577451 Karnataka India Department of.m.thematics COMSATS Institute of Information Technology Sahiwal 57000 Pakistan Department of.m.thematics COMSATS Institute of Information Technology Islamabad 44000 Pakistan Department of.m.chanical and Civil Engineering Purdue University Northwest Indiana 46391 U. S. A

The effect of non-linear convection in a laminar three-dimensional Oldroyd-B fluid flow is addressed. The heat transfer phenomenon is explored by considering the non-linear thermal radiation and heat generation/absorption. The boundary layer as- sumptions are taken into account to govern the mathematical model of the flow analy- sis. Some suitable similarity variables are introduced to transform the partial differen- tial equations into ordinary differential systems. fifth-order techniques with the shooting method The Runge-Kutta-fehlberg fourth- and are used to obtain the solutions of the dimensionless velocities and temperature. The effects of various physical parameters on the fluid velocities and temperature are plotted and examined. A comparison with the exact and homotopy perturbation solutions is made for the viscous fluid case, and an excellent match is noted. The numerical values of the wall shear stresses and the heat transfer rate at the wall are tabulated and investigated. The enhancement in the values of the Deborah number shows a reverse behavior on the liquid velocities. The results show that the temperature and the thermal boundary layer are reduced when the non- linear convection parameter increases. The values of the Nusselt number are higher in the non-linear radiation situation than those in the linear radiation situation.

关键词： nonlinear thermal convection nonlinear thermal radiation Oldroyd-B fluid,convective boundary condition heat source/sink

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DYNAmIC STRAIN AGING BEHAVIOR Of K40S ALLOY

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Acta metallurgica Sinica(English Letters) 2003年第6期16卷 473-477页

作者： f.m. Yang, X.f. Sun, H.R. Guan and Z.Q. HuInstitute of.m.tal Research, The Chinese Academy of Sciences, Shenyang 110016, China Inst. of.m.tal Res. Chinese Acad. of Sci. Shenyang 110016 China

The dynamic strain aging behavior during tensile tests of K40S alloy has been investigated in the temperature range of 25-1100℃ with the strain rate range from 10-4 to 10-3s-1. The results show that four different types of serration, identified as A, B, C and E type serration were observed in the temperature range of 300-600℃. The strain exponents for onset of the serrated flow were calculated as 1.21, 2.19 and 1.61, and the activation energies as 121, 40 and 67kJ/mol for E, B and C type serration respectively. The main mechanism for dynamic strain aging discussed in light of the strain exponent and the activation energy.

关键词： dynamic strain aging serrated flow strain exponent activation energy

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THE INfLUENCE Of IRRADIATEDWHEAT ON LONGEVITY AND REPRODUCTIONOf THE GRAIN WEEVIL Sitophilus granarius LINNE 1758

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核农学报 1993年第4期 223-226页

作者： V. Arthur,f.m. Wiendl,S.S.H. franco Nuclear Nuclear Nuclear Energy Center for Agriculture University of So Paulo Piracicaba SP. 13400—970 Brazil Energy Center for Agriculture University of So Paulo Piracicaba SP. 13400—970 Brazil Energy Center for Agriculture University of So Paulo Piracicaba SP. 13400—970 Brazil

The main objective of the present research was to determine the influence of gamma irradiations on wheat,the diet of the grain weevil,using as parameters of the longevity and reproduction of this *** doses of 60Coγ-rays applied to wheat grains were O(control),125,250,500,1000,2000,and 4000 Gy,at a dose rate of 3000 Gy per *** longevity,expressed as life-expectancy in days,and the reproduction expressed as the number of f1 adults,showed no differences up to the dose of 2000 *** wheat irradiated with the dose of 4000 Gy induced a lower life-expectancy of the insects fed with irradiated wheat and a smaller number of insects of the f1 generation.

关键词： Wholesomeness of irradiated foods stored grains irradiation radiation grain weevil

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