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The Impact of Topography on Social Factors,a Case Study of Montenegro

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Journal of Mountain Science 2014年第1期11卷 131-141页

作者： TElBISZ Tamás BOTTlIK Zsolt MARI lászló KOSZEGI Margit Department of Physical Geography Eotvos University Department of Regional Science Eotvos University

Relationships between environmental and social factors have long been studied by ***,GIS-aided statistical analysis provides new tools to explore these *** order to detect the impact of topography on social factors,we selected the country of Montenegro as a case example due to its high topographic *** compared the spatial pattern of population,settlements and ethnic minorities to physical geographic factors,especially to topography,but lithology and land cover data were also taken into *** found that certain factors are closely correlated,*** settlement density linearly decreases with elevation,while the characteristic settlement area shows an exponential increase *** population density is not related to absolute elevation,but it is in close correlation with height(*** relative to the local minimum).Population change and illiteracy are also topography-related social *** the contrary,the variable ethnic pattern of Montenegro is influenced by historical,political and economic effects rather than by environmental factors or topographic *** a conclusion we state that in the scale of a country or a region,the environment can strongly impact some social factors.

关键词： Human-environment relations Dinarides GIS Settlements Population Ethnic groups

Phylogenetic relationships of Cypriniformes and plasticity of pharyngeal teeth in the adaptive radiation of cyprinids

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Science China(life Sciences) 2019年第4期62卷 553-565页

作者： Wenjing Tao lei Yang Richard l.Mayden Shunping He Key laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences Institute of Hydrobiology Chinese Academy of Sciences Key laboratory of Freshwater Fish Reproduction and Development (Ministry of Education) Key Laboratory of Aquatic Science of Chongqing School of Life Sciences Southwest University Florida Museum of Natural History University of Florida Department of Biology Saint Louis University CAS Center for Excellence in Animal Evolution and Genetics Chinese Academy of Sciences

The Cypriniformes comprise approximately 4,200 species accounting for 25% of the diversity of all freshwater fish, which is widely distributed across the world's continents except Antarctica, South America, and Australia. The highest species diversity is found in Southeastern Asia. Despite its remarkable species diversity and broad-scale geographic patterns of distribution, the evolutionary history of this major freshwater fish group remains largely unresolved. To gain insight of the evolutionary history of Cypriniformes, we present a phylogeny of this group using 1 mitochondrial gene and 15 nuclear genes comprising a total of14,061 bp. Bayesian inference using all gene fragments yielded a well resolved phylogeny, which is mostly consistent with topologies obtained from Maximum likelihood analyses. Our results further confirmed the monophyly of Cypriniformes and seven constituent subclades including Cyprinidae, Catostomidae, Gyrinocheilidae, Balitoridae, Cobitidae, Nemacheilidae, and Botiidae. Bayesian divergence time analysis indicated that the origin of the Cypriniformes was about 193 Mya during the early Jurassic, coinciding with the onset of the Pangaea breakup. The basal divergence of Cypriniformes is 154 Mya during the late Jurassic. Our findings from molecular divergence and biogeographical analysis indicate the most likely initial geographical range of the ancient Cypriniformes was both East and South Asia(Southeastern area of Mesozoic laurasia). Moreover, the burst in species diversity in Cyprinidae afforded by the nearly worldwide colonization is possibly in response to the plasticity of pharyngeal dentition. The present study demonstrates that the Cypriniformes was about 193 Mya during the early Jurassic,coinciding with the onset of the Pangaea breakup. The plasticity of pharyngeal dentition of cyprinids might contribute to the burst and radiation of this lineage. The phylogenetic and biogeographic analyses in this study help to improve our understanding

关键词： phylogeny biogeographic analyses Cypriniformes pharyngeal teeth adaptive radiation

Sharing Results with Clinical Trial Participants： Insights from an Online Survey of Chinese Consumers

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Chinese Medical Journal 2016年第8期129卷 1007-1008页

作者： Janelle R Keys Julie A Monk Karen l Woolley ProScribe-Envision Pharma Group Sydney NSW 2113 Australia Faculty of Science Health Education and Engineering University of the Sunshine Coast Maroochydore DC Queensland Australia Faculty of Health and Behavioural Sciences University of Queensland Brisbane Queensland Australia

To the Editor：Clinical trial participants have a right to know the results from the trials that they enable. European and North American research,however,shows that trial results are rarely shared with participants. Given the increase in industry-sponsored trials in China,we conducted the first investigation into Chinese consumer views about sharing the clinical trial results with participants.

关键词： Sharing Results Clinical Trial Participants Chinese Consumers

The N-terminus of COX-1 and its effect on cyclooxygenase-1 catalytic activity

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Journal of Genetics and Genomics 2010年第2期37卷 117-123页

作者： Sean Phipps Michael J. Turner Daniel l. Simmons Chemistry and Biochemistry Department Brigham Young University

Cyclooxygenases are encoded by COX-1 and COX-2. They share over sixty percent sequence identity in human and are similar to each other in their crystallographic structures. One major difference in the primary structure of these two isozymes is the presence of eight amino acids in the amino-terminal region of COX-1 that are not present in COX-2. The function of this amino acid sequence is unknown. In this study, a human COX-1 mutant （Δ7aa） with this sequence removed was studied in parallel with COX-1. Signal peptide cleavage, N-linked glycosylation, protein expression, distribution and dimerization were not affected by the mutation. The mutant was enzymati-cally active and showed the same sensitivity toward aspirin. The KM for the enzyme remained the same as COX-1. However, the Vmax of the COX-1 mutant decreased by 3.3-fold. We conclude that the COX-1 specific amino-terminal sequence has a subtle but detectable effect on COX-1 catalysis.

关键词： COX-1 COX-2 dimerization glycosylation aspirin KM Vmax

Origin of extension twinning-mediated static recrystallization and unique parallel alignment of(0001) poles to transverse direction in Mg-3Al-0.4Mn(mass%) alloy sheet

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Journal of Magnesium and Alloys 2023年第9期11卷 3200-3213页

作者： T.Nakata C.Xu l.Geng S.Kamado Nagaoka University of Technology 1603-1KamitomiokaNagaoka 940-2188Japan School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001China

The origin of unique parallel alignment of(0001) poles to transverse direction(TD) was investigated using Mg-3Al-0.4Mn(mass%)alloy sheets rolled with different process conditions. When rolling was performed with intermediate reheating, the alloy showed a sluggish static recrystallization(SRX) behavior during post-annealing, facilitating the nucleation and growth of statically recrystallized grains from extension twins. This resulted in the apparent texture component with the parallel alignment of the(0001) poles to the TD, and the sheet exhibited good ductility for both the rolling direction(RD) and TD. In contrast, continuous rolling without intermediate reheating led to the formation of severely deformed regions near double twins. SRX was promoted at such regions, forming a typical basal textural feature with weak RD-split of the(0001) poles. Although extension twins were formed after the continuous rolling, SRX was facilitated at the severely deformed regions with double twins, and the formation of the unique alignment of the(0001) poles to the TD was suppressed. The RD-split texture led to the large elongation to failure along the RD, while it along the TD decreased owing to the narrow distribution of the(0001)poles toward the TD, resulting in the in-plane anisotropy in ductility.

关键词： Magnesium Rolling Twinning Static recrystallization Texture

ElTA-WAVE IN A SIMPlE 1-D 2 x 2 HYPERBOlIC PROBlEM

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Journal of Computational Mathematics 1996年第4期14卷 311-318页

作者： S.l. Yang(Institute of Applied Mathematics, Chinese Academy of Sciences, Beijing, China) Institute of Applied Mathematics Chinese Academy of Sciences Beijing China

A simple one-dimensional 2 x 2 hyperbolic system is considered in the *** model contains a linear hyperbolic equation, as well as a hyperbolic equation ofwhich the coefficients are about the solution of the linear one. The exact solution ispresented and discussed, then numerical experiments are given by TVD (or MmB)type schemes for Riemann problems. From the results, we know that the solutionsdo have δ-waves for some suitable initial data.

关键词： Zhang Figure DElTA-WAVE IN A SIMPlE 1-D 2 HYPERBOlIC PROBlEM

Effect of Hall current on MHD natural convection flow from vertical permeable flat plate with uniform surface heat flux

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Applied Mathematics and Mechanics(English Edition) 2011年第9期32卷 1127-1146页

作者： l.K.SAHA S.SIDDIQA M.A.HOSSAIN Department of Mathematics University of DhakaDhaka 1000Bangladesh Department of Mathematics COMSATS Institute of Information TechnologyPark RoadChak ShahzadIslamabad 44000Pakistan

The effect of the Hall current on the magnetohydrodynamic （MHD） natural convection flow from a vertical permeable flat plate with a uniform heat flux is analyzed in the presence of a transverse magnetic *** is assumed that the induced magnetic field is negligible compared with the imposed magnetic *** boundary layer equations are reduced to a suitable form by employing the free variable formulation （FVF） and the stream function formulation （SFF）.The parabolic equations obtained from FVF are numerically integrated with the help of a straightforward finite difference ***,the nonsimilar system of equations obtained from SFF is solved by using a local nonsimilarity method,for the whole range of the local transpiration parameter ζ.Consideration is also given to the regions where the local transpiration parameter ζ is small or large ***,in these particular regions,solutions are acquired with the aid of a regular perturbation *** effects of the magnetic field M and the Hall parameter m on the local skin friction coefficient and the local Nusselt number coefficient are graphically shown for smaller values of the Prandtl number P r （= 0.005,0.01,0.05）.Furthermore,the velocity and temperature profiles are also drawn from various values of the local transpiration parameter ζ.

关键词： magnetohydrodynamic (MHD) natural convection Hall current permeable plate heat flux

Thermal Characterization of lauric Acid and Stearic Acid Binary Eutectic Mixture in latent Heat Thermal Storage Systems with Tube and Fins

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Journal of Wuhan University of Technology(Materials Science) 2017年第4期32卷 753-759页

作者：丁磊 WANG lixiong Georgios Kokogiannakis lü Yajun 周卫兵 School of Architecture Tianjin University Sustainable Buildings Research Centre University of Wollongong School of Architecture North China University of Water Resources and Electric Power School of Materials Science and Engineering Wuhan University of Technology

In order to obtain the suitable phase change material（PCM） with low phase change temperature and improve its heat transfer rate, experimental investigation was conducted. Firstly, different mass ratios of lauric acid（lA） and stearic acid（SA） eutectic mixtures were prepared and characterized by differential scanning calorimetry（DSC）. Then, the performance of eutectic mixture during charging process under different fin widths in vertical condition, and performance during charging and discharging processes under different inlet temperature heat transfer fluid（HTF） in horizontal condition were investigated, respectively. The results revealed that the lA-SA eutectic mixture had the suitable phase change temperature and desired latent heat for low-temperature water floor heating system. Wide fins and high inlet temperature HTF significantly enhanced the transfer rate and decreased the melting time.

关键词： lA-SA binary eutectic mixture thermal properties heat exchanger heat transfer mechanism

Diffusion behavior of Cr in gradient nanolaminated surface layer on an interstitial-free steel

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Journal of Materials Science & Technology 2019年第3期35卷 460-464页

作者： S.l.Xie Z.B.Wang K.lu Shenyang National laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences School of Materials Science and Engineering University of Science and Technology of China

Nanolaminated structures composed of low-angle grain boundaries(lAGBs) possess high thermal stability. In this paper, a gradient nanolaminated(GNl) surface layer with smooth finish was fabricated on an interstitial-free steel by means of surface mechanical rolling treatment. Microstructural observations demonstrated that the average lamellar thickness is about 80 nm in the topmost surface layer and increases with increasing depth. High thermal stability was confirmed in the GNl surface layer after annealing at 500℃. Diffusion measurements showed that effective diffusivity of Cr in GNl layer is 4–6 orders of magnitude higher than lattice diffusivity within the temperature range from 400 to 500℃. This might be attributed to numerous lAGBs or dislocation structures with a higher energy state in the GNl surface layer. This work demonstrates the possibility to advanced chromizing(or other surface alloying)processes of steels with formation of GNl surface layer, so that a thicker alloyed surface layer with a stable nanostructure is achieved.

关键词： Gradient nanolaminated structure Interstitial-free steel Diffusion low-angle grain boundary Surface mechanical rolling treatment