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Predicting the effect of climate change on a range-restricted lizard in southeastern Australia

Current Zoology 2018年第2期64卷 165-171页

作者： Bezeng S. BEZENg Solomon g. TESFAMICHAEL Buddhi DAYANANDA African Centre for DNA Barcoding Department of Botany and Plant Biotechnology University of Johannesburg P0Box 524 APK Campus 2006 Johannesburg South Africa Department of geography Environmental Managementand Energy Studies University of Johannesburg P0 Box 524 APK Campus 2006 Johannesburg South Africa School of Life Sciences University of Technology Sydney Broadway NSW 2007 Australia

Climate change is ranked as one of the most severe threats to global biodiversity. This global phenomenon is particularly true for reptiles whose biology and ecology are closely linked to climate. In this study, we used over 1,300 independent occurrence points and different climate change emission scenarios to evaluate the potential risk of changing climatic conditions on the current and future potential distribution of a rock-dwelling lizard; the velvet gecko. Furthermore, we investigated if the current extent of protected area networks in Australia captures the full range distribution of this species currently and in the future. Our results show that climate change projections for the year 2075 have the potential to alter the distribution of the velvet gecko in southeastern Australia. Specifically, climate change may favor the range expansion of this species to encompass more suitable habitats. The trend of range expansion was qualitatively similar across the different cli- mate change scenarios used. Additionally, we observed that the current network of protected areas in southeast Australia does not fully account for the full range distribution of this species currently and in the future. Ongoing climate change may profoundly affect the potential range distribution of the velvet gecko population. Therefore, the restricted habitat of the velvet geckos should be the focus of intensive pre-emptive management efforts. This management prioritization should be extended to encompass the increases in suitable habitats observed in this study in order to maximize the microhabitats available for the survival of this species.

关键词： bioclirnatic variables climate change environmental niche models range expansion reptiles.

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The Binary Black Hole Scenario for the BL Lacertae Object AO 0235+16

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Chinese journal of Astronomy and Astrophysics 2003年第6期3卷 513-525页

作者： g.E.Romero jun-HuiFan S.E.Nuza InstitutoArgentinodeRadioastrononia C.C.5（1894）VillaElisaBs.As.Argentina CenterforAstrophysics GuangzhouUniversityGuangzhou510400 DepartamentodeFisicaj.j.giambiagi FCENUBAPabellon1CiudadUniversitaria1428BuenosAiresArgentina

Recent analysis of the long term radio light curve of the extremely variableBL Lacertae object AO 0235+16 by Raiteri et al. have revealed the presence of recurrent outburstswith a period of ～ 5.7 +- 0.5 yr. Periodicity analysis of the optical light curve also showsevidence for a shorter period. Here we discuss whether such a behavior can be explained by a binaryblack hole model where the accretion disk of one of the supermassive black holes is precessing dueto the tidal effects of the companion. We estimate the mass of the accreting hole and analyzeconstraints on the secondary mass and the orbital parameters of the system. It is possible toprovide a viable interpretation of the available multiwavelength data.

关键词： galaxies: active BL lacertae objects: individual: AO 0235+16 -gamma rays:theory black hole physics

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Monthly soil erosion monitoring based on remotely sensed biophysical parameters: a case study in Strymonas river basin towards a functional pan-European service

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International journal of Digital Earth 2012年第6期5卷 461-487页

作者： Panos Panagos Christos g.Karydas Ioannis Zgitas Luca Montanarella joint Research Centre of the European Commission Institute for Environment and SustainabilityIspraItaly School of Forestry and Natural Environment Laboratory of Forest Management and Remote SensingAristotle University of ThessalonikiThessalonikiGreece

Currently,many soil erosion studies at local,regional,national or continental scale use models based on the USLE-family *** of these models pay little attention to seasonal changes,despite evidence in the literature which suggests that erosion risk may change rapidly according to intra-annual rainfall figures and vegetation *** paper emphasises the aspect of seasonality in soil erosion mapping by using month-step rainfall erosivity data and biophysical time series data derived from *** latter,together with other existing pan-European geo-databases sets the basis for a functional pan-European service for soil erosion monitoring at a scale of 1:500,*** potential service has led to the establishment of a new modelling approach(called the g2 model)based on the inheritance of USLE-family *** g2 model proposes innovative techniques for the estimation of vegetation and protection *** model has been applied in a 14,500 km 2 study area in SE Europe covering a major part of the basin of the cross-border river,*** results were verified with erosion and sedimentation figures from previous *** study confirmed that monthly erosion mapping would identify the critical months and would allow erosion figures to be linked to specific land uses.

关键词： soil erosion biophysical parameters digital earth European geo-databases Strymonas/Struma Sobel filter

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Controllable synthesis and surface modification of molybdenum oxide nanowires: a short review

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Tungsten 2019年第4期1卷 258-265页

作者： Dimberu g.Atinafu Wenjun Dong Minggang Du School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Science and Technology On Vehicle Transmission Laboratory China North Vehicle InstituteBeijing 100072China

Transition metal oxides are found to have overwhelming applications in energy,electronics,catalytic,and bio-and micromechanical systems.A recent report emphasized the current advancements in molybdenum oxide(MoO_(x))nanowire synthesis and the corresponding surface-functionalized nanostructured materials based on our previously reported *** preparation of the nanowires and their applications were systematically ***_(x) nanowires combined with substrates exhibited remarkable performances for high energy storage and power densities with high *** addition,the review concluded the future advancements of MoO_(x) nanowires.

关键词： Molybdenum oxide nanowire Controllable synthesis Surface modification

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Toward Analytic Solution of Nonlinear Differential Difference Equations via Extended Sensitivity Approach

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Communications in Theoretical Physics 2012年第1期57卷 5-9页

作者： g.Darmani S.Setayeshi H.Ramezanpour Department of Electrical Engineering Sadjad Institute of Higher EducationMashhadIran Department of Nuclear Engineering and Physics Amirkabir University of TechnologyTehranIran

In this paper an efficient computational method based on extending the sensitivity approach(SA) is proposed to find an analytic exact solution of nonlinear differential difference *** this manner we avoid solving the nonlinear problem *** extension of sensitivity approach for differential difference equations(DDEs),the nonlinear original problem is transformed into infinite linear differential difference equations,which should be solved in a recursive *** the exact solution is determined in the form of infinite terms series and by intercepting series an approximate solution is *** examples are employed to show the effectiveness of the proposed approach.

关键词： differential difference equation sensitivity approach exact solution

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Pathogenesis and clinical spectrum of primary sclerosing cholangitis

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World journal of gastroenterology 2017年第14期23卷 2459-2469页

作者： Neelam g gidwaney Swati Pawa Kiron M Das Division of gastroenterology and Hepatology Rutgers-Robert Wood Johnson Medical School

Primary sclerosing cholangitis(PSC) is a disease of the biliary tract, which has been documented in the literature since 1867. This disease has a strong predilection for affecting men and can be seen in individuals as young as 2 years of age. PSC has a strong associated with inflammatory bowel disease, more commonly with ulcerative colitis, and is also part of the clinical spectrum of Ig g4-related diseases. Smallduct PSC, a variant of PSC, also has an association with inflammatory bowel disease. The exact pathogenesis of PSC is not well understood at present, however, is likely a combination of a genetic predisposition with alteration of the molecular structure of the gut. Abnormal serum liver chemistry and presence of certain autoimmune markers are usually the first indicators leading to a diagnosis of PCS, however, these may often be normal in early stages of this disease. The diagnosis is made by cholangiography, which is now considered the gold standard. PSC is a known pre-malignant condition. Such patients have an increased risk of developing cholangiocarcinoma, gallbladder neoplasia, and colon cancer. Many new treatment modalities have emerged in the recent past, including anti-tumor necrosis factor-α and anti-integrins; however, liver transplantation is the only known cure for PSC. Despite past and present research, PSC remains an enigmatic biliary disease with few viable treatment options.

关键词： Primary sclerosing cholangitis Cholestasis Inflammatory bowel disease Autoimmune gallbladder neoplasia Cholangiocarcinoma Igg4 related disease Colon cancer Liver transplant

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Spatial Channel Sounding Based on Bistatic Synthetic Aperture Radar Principles

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journal of Electronic Science and Technology 2018年第3期16卷 251-268页

作者： Lin-Li Cui David g.Michelson Wen-Qin Wang the University of Electronic Science and Technology of China Chengdu 611731 the Radio Science Laboratory University of British ColumbiaVancouver V6T 1Z4

In this paper, we propose a simplified spatial channel sounding method by utilizing bistatic synthetic aperture radar(BiSAR) principles. Despite the different deployment geometries compared with a conventional BiSAR system, the feasibility of the approach is established by 1) the proposed method achieves a better spatial resolution than conventional directional channel sounders and 2) reconstruction algorithms based on time-domain backprojection in conjunction with a digital elevation model provide a good imaging performance and are suitable for reconstructing the spatial distribution of scatterers. Simulations of a high-speed rail(HSR) scenario demonstrate that the estimated power delay profiles(PDPs) and power angle profiles(PAPs) are close to the actual values.

关键词： Bistatic synthetic aperture radar(bistatic SAR) channel sounding spatial channel modeling

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Finite element investigation of steel built-up shear links subjected to inelastic deformations

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Earthquake Engineering and Engineering Vibration 2004年第2期3卷 195-203页

作者： Peter Dusicka Ahmad M.Itani Ian g.Buckle Department of Civil and Environmental Engineering Portland State UniversityP O.Box 751PortlandOregon97207USA Assistant Professor Department of Civil Engineering Mail Stop 258University of NevadaRenoNevada89557USA Associate Professor Department of Civil Engineering Mail Stop 258University of NevadaRenoNevada89557USA Professor

Non-linear finite element models accounting for large displacements have been used to investigate the behavior of steel built-up shear links that had previously been tested using large-scale experiments. The links were designed using steel grades with yield points ranging from high to low strengths. The objectives of the numerical analyses were to further investigate the non-linear behavior and to correlate the numerical results with experimental observations. Elasto-plastic as well as cyclic stress-strain material properties were incorporated to study the influence of material behavior on the overall shear link response. Non-linear monotonie analyses of the shear links incorporating the cyclic stress-strain steel properties resulted in similar trends in the response as the backbone curves recorded from the physical experiments. The numerical models of built-up shear links utilizing structural grade steels closely correlated to the experimentally recorded shear strength. Models utilizing low yield point steels overestimated the shear strength, which was caused by the characteristics of cyclic behavior of those steels. The detailed numerical models also allowed for investigation of the plastic strain demands on the different components of the link. It was shown that finite element models combined with appropriate stress-strain relationship may be used with confidence to check the design of shear links of different steel grades and sectional geometries.

关键词： finite element investigation steel built-up shear link inelastic deformation

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A theoretical study on the elastic deformation of cellular phase and creation of necrosis due to the convection reaction process inside a spherical tumor

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International journal of Biomathematics 2016年第6期9卷 273-306页

作者： Bibaswan Dey g. P. Raja Sekhar Department of MathematicsIndian Institute of Technology Kharagpur Kharagpur 721302 West Bengal India

Several biological processes, such as convective nutrient transport and convective drug delivery in biological tissues involves the transvascular and interstitial movement of biofluids. This work addresses transvascular and interstitial transport of nutrient inside a spherical tumor. Most of the biological tissues behave like deformable porous materiM and show mechanical behavior towards the fluid motion, due to the fact, that the forces like the drag, which is associated with fluid flow may compress the tissue material. On the macroscopic level, transport of solutes like nutrients, drug molecules, etc. within the tumor interstitial space is modeled. The hydrodynamic problem is treated with biphasic mixture theory under steady state and spherically symmetry situation. The transvascular transport of nutrient is modeled with the modified Sterling＇s equation. The present model describes the overall nutrient distribution and predicts various criteria for the necrosis formation inside the tumor. Present study justifies that the parameters, which controls the nutrient supply to the tumor interstitial space through the blood vessel network inside the tumor, competes with reversible nutrient consumption kinetics of the tumor cells. This study also finds the role of some of those parameters on the deformation of cellular phase of the tumor as a consequence of interstitial fluid flow.

关键词： Tumor vasculature isolated tumor biphasic mixture theory effectivenessfactor necrotic core.

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Involvement of eicosanoids in the pathogenesis of pancreatic cancer: the roles of cyclooxygenase-2 and 5-lipoxygenase

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World journal of gastroenterology 2014年第31期20卷 10729-10739页

作者： Lawrence M Knab Paul j grippo David j Bentrem Department of Surgery Northwestern University Feinberg School of Medicine Robert H Lurie Comprehensive Cancer Center Northwestern University jesse Brown VA Medical Center

The interplay between inflammation and cancer progression is a growing area of research. A combination of clinical, epidemiological, and basic science investigations indicate that there is a relationship between inflammatory changes in the pancreas and neoplastic progression. Diets high in ω-6 polyunsaturated fatty acids provide increased substrate for arachidonic acid metabolism by cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LOX) to form eicosanoids. These eicosanoids directly contribute to pancreatic cancer cell proliferation. Both COX-2 and 5-LOX are upregulated in multiple cancer types, including pancreatic cancer. In vitro studies using pancreatic cancer cell lines have demonstrated upregulation of COX-2 and 5-LOX at both the mRNA and protein levels. When COX-2 and 5-LOX are blocked via a variety of mechanisms, cancer cell proliferation is abrogated both in vitro and in vivo. The mechanism of COX-2 has been shown to include effects on apoptosis as well as angiogenesis. 5-LOX has been implicated in apoptosis. The use of COX-2 and 5-LOX inhibitors in clinical studies in patients with pancreatic cancer has been limited. Patient enrollment has been restricted to those with advanced disease which makes evaluation of these drugs as chemopreventive agents difficult. COX-2 and 5-LOX expression have been shown to be present during the early neoplastic changes of pancreatic cancer, well before progression to invasive disease. This indicates that the ideal role for these interventions is early in the disease process as preventive agents, perhaps in patients with chronic pancreatitis or hereditary pancreatitis.

关键词： Arachidonic acid Eicosanoid Cyclooxygenase-2 5-lipoxygenase Pancreatic cancer Inflammation

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