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Pancreas transplantation in the mouse

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Hepatobiliary & Pancreatic Diseases International 2010年第3期9卷 254-258页

作者： Liu, xiang-Yan Xue, Liang zheng, xiang Yan, Sheng zheng, Shu-Sen Zhejiang Univ Sch Med Affiliated Hosp 1 Div Hepatobiliary & Pancreat Surg Hangzhou 310003 Zhejiang Peoples R China

BACKGROUND: Pancreas transplantation is the only established treatment to achieve long-term normoglycemia and insulin independence in patients with insulin-dependent diabetes mellitus. However, many complications both during and post-transplantation have limited the progress of pancreas transplantation. Mice are the widely used laboratory animals that have been used to establish pancreas transplant models. The pathogenesis and the treatment of pancreas allograft rejection have been studied during the last twenty years. This review introduces four different mouse pancreas transplantation models established by different centers. DATA SOURCES: We reviewed the three mostly reported mouse pancreas transplantation models in the literature (Pub Med), and compared them with a novel mouse model established at our center. RESULTS: In this review, four different models of mouse pancreas transplantation were compared in terms of surgical technique, immediate success rate, advantages and disadvantages. CONCLUSIONS: The mouse model is a useful tool to study pancreas transplantation-related diseases and their treatment. The findings from this model help to improve human pancreas transplantation in the future. (Hepatobilinty Pancreat Dis Int 2010; 9:254-258)

关键词： pancreas transplantation model, animal mouse

Testing the distance-duality relation with data from galaxy clusters and type Ia supernovae

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Research in Astronomy and Astrophysics 2011年第8期11卷 895-901页

作者： xiang-Yun Fu Pu-Xun Wu Hong-Wei Yu zheng-xiang Li Institute of Physics Hunan University of Science and Technology Xiangtan 411201 China Center for Nonlinear Science and Department of Physics Ningbo University Ningbo 315211 China Department of Physics and Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education Hunan Normal University Changsha 410081 China

We test the distance-duality （DD） relation by combining the angular diameter distance DA provided by two galaxy cluster samples compiled by De Filippis et al. （the elliptical β model） and Bonamente et al. （the spherical β model）, and the luminosity distance DL from Constitution and Union2 type Ia supernova （SNe Ia） datasets. To obtain DL associated with the observed DA at the same redshift, we smooth the noise of the SNe Ia in a model-independent way, obtain the evolutionary curve of DL and, finally, test the DD relation. We find that the elliptical β model, when compared with the SNe Ia from the Constitution compilation, is only consistent with the DD relation at the 3σ confidence level （CL）, while the spherical β model is incompatible with the DD relation at the 3σ CL. For the Union2 compilation, the De Filippis and Bonamente samples are marginally compatible with the validity of the DD relation at the 1σ and 2σ CLs, respectively.

关键词： galaxies: distances and redshifts -- galaxies: clusters: general -- super- novae: general

Three-dimensional tracking of GLUT4 vesicles in TIRF microscopy

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 232-240页

作者： xiang-ping WU Jie-yue LI Ying-ke XU Ke-di XU Xiao-xiang zheng Department of Biomedical Engmeermg Zhejiang University Hangzhou 310027 China College of Information Engineering China Jiliang University Hangzhou 310018 China

TIRF microscopy has provided a means to view mobile granules within 100 nm in size in two *** quantitative analysis of the position and motion of those granules requires an appropriate tracking *** this paper,we present a new tracking algorithm combined with the unique features of *** a fluorescence correction procedure was processed to solve the problem of fluorescence bleaching over *** granules were then segmented from a time-lapse image stack by an adaptive background subtraction *** filter was introduced to estimate and track the granules that allowed reducing searching range and hence greater reliability in tracking *** the tracked granules were located in x-y plane,the z-position was indirectly inferred from the changes in their *** the experiments the algorithm was applied in tracking GLUT4 vesicles in living adipose *** results indicate that the algorithm has achieved robust estimation and tracking of the vesicles in three dimensions.

关键词： GLUT4 Total internal reflection fluorescence (TIRF) microscopy Adaptive background subtraction Kalman filter Fluorescence correction

Sedimentary environment of vermicular red clay in South China

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Journal of Mountain Science 2017年第3期14卷 513-526页

作者： YANG Li-hui zheng xiang-min YE Wei School of Geographic Science East China Normal UniversityShanghai 200214China Anhui Key Laboratory of Natural Disaster Process and Protection Research Anhui Normal UniversityWuhu 241003China College ofC eography and Environmental ScienceZhejiang Normal UniversityJinhua 321004China

Increasing interest in recent years has focused on vermicular red clay(VRC) in southern China due to its controversial sedimentary environment and provenance. Grain size is a useful way to determine sedimentary environment and provenance. Fisher Linear Discriminant Analysis(LDA) is a common and widely used method for multivariate statistical analysis. Based on a proper training sample set, the LDA can be used to discuss the sediment provenance. In this study, grain size data for 77 Malan loess samples and 41 floodplain deposit samples were used as a training sample set to deduce a Fisher linear discriminant function. Then, 299 VRC samples from 6 Quaternary red clay profiles were analyzed using the discriminant function. Grain size parameters and microscopic images of quartz grains separated from the VRC were evaluated in detail to determine the VRC sedimentary environment in south China. The results show that VRC profiles can be classified into two regions: the Chiang-nan Hilly Region and Wuyi Mountains Region. The VRC samples in the Chiang-nan Hilly Region originated from eolian dust deposits. This VRC is characterized by a higher content of fine particles(<20 μm) and lower average transport kinetic energy than loess in a C-M plot. The quartz grain sizes and microscope images of this VRC suggest that it could be a polyphyletic mixture of far-sourced and nearsourced eolian deposits. The far-sourced eolian deposits share similar provenance with Xiashu loess and were transported by the East Asian winter monsoon. The near-sourced eolian deposits were dust emitted from the adjacent floodplain. In the Wuyi Mountains Region, the rugged topography weakened the dustfall and strengthened the reconstructive effect of hydrodynamic forces during the Quaternary glacial periods. The VRC in this region was reworked strongly by water and retained typical hydraulic characteristics no matter the source.

关键词： Vermicular red clay Grain size Linear discriminant analysis Eolian deposits Quaternary

Will Earth's next supercontinent assemble through the closure of the Pacific Ocean?

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National Science Review 2022年第12期9卷 73-81页

作者： Chuan Huang zheng-xiang Li Nan Zhang Earth Dynamics Research Group The Institute for Geoscience Research(TIGeR) School of Earth and Planetary Sciences Curtin University Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University

Earth’s known super continents are believed to have formed in vastly different ways,with two endmembers being introversion and *** former involves the closure of the internal oceans formed during the break-up of the previous supercontinent,whereas the latter involves the closure of the previous external super ***,it is unclear what caused such diverging behavior of supercontinent cycles that involved first-order interaction between subducting tectonic plates and the *** we address this question through 4D geo dynamic modeling using realistic tectonic *** results show that the strength of the oceanic lithosphere plays a critical role in determining the assembly path of a *** found that high oceanic lithospheric strength leads to introversion assembly,whereas lower strength leads to extroversion assembly.A theoretically estimated reduction in oceanic crustal thickness,and thus its strength,during Earth’s secular cooling indicates that introversion was only possible for the Precambrian time when the oceanic lithosphere was stronger,thus predicting the assembling of the next supercontinent Amasia through the closure of the Pacific Ocean instead of the Indian-Atlantic *** work provides a new understanding of the secular evolution of plate tectonics and geodynamics as the Earth cooled.

关键词： yield stress oceanic lithosphere introversion extroversion supercontinent cycle

Effect of organic matter on phosphorus recovery from sewage sludge subjected to microwave hybrid pretreatment

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Journal of Environmental Sciences 2016年第1期28卷 29-36页

作者： Yawei Wang Qingcong Xiao Hui Zhong xiang zheng Yuansong Wei State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China School of Environment and Natural Resources Renmin University of China Beijing 100872 China CSD IDEA (Beijing) Environmental Test& Analysis Co. Ltd. Beijing 100192 China

Microwave（MW） hybrid processes are able to disrupt the flocculent structure of complex waste activated sludge,and help promote the recovery of phosphorus as *** this study,to optimize struvite yield,（1） the characteristics of matter released in MW-hybrid treatments were compared,including MW,MW-acid,MW-alkali,MW-H2O2,and MW-H2O2- *** results showed that selective release of carbon,nitrogen,phosphorus,Ca^2＋,and Mg^2＋ achieved by sludge pretreatment using MW-hybrid ***-H2O2 is the recommended sludge pretreatment process for phosphorus recovery in the form of *** ratio of Mg^2＋：NH4^＋-N：PO4^3--P was 1.2：2.9：1 in the supernatant.（2） To clarify the effects of organic matter on struvite recovery,the composition and molecular weight distribution of organic matters were *** molecular weight COD was found to facilitate the removal rate of NH4^＋-N and PO4^3-P via crystallization,and the amorphous struvite crystals（〈1 kDa） from the filtered solutions had high ***,the present study reveals the necessity of taking into consideration the interference effect of high molecular weight organic matters during struvite crystallization from sewage sludge.

关键词： Microwave pretreatment Sewage sludge Molecular weight distribution Phosphorus recovery Struvite

固溶处理对Mg-1.5Er-1.0Zn-0.3Zr合金组织和性能的影响

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材料热处理学报 2024年第9期45卷 124-133页

作者：贺俊光冯武云文九巴龚圆郑向阳河南科技大学材料科学与工程学院河南洛阳471003 有色金属新材料与先进加工技术省部共建协同创新中心河南洛阳471023

采用光学显微镜(OM)、扫描电镜(SEM)、电化学实验和拉伸实验等研究固溶处理对Mg-1.5Er-1.0Zn-0.3Zr合金组织、耐蚀性能和力学性能的影响。结果表明:铸态合金的显微组织主要由α-Mg基体、Mg_(3)Er_(2)Zn_(3)、Mg_(24)Er_(5)和MgErZn_(2)... 详细信息

采用光学显微镜(OM)、扫描电镜(SEM)、电化学实验和拉伸实验等研究固溶处理对Mg-1.5Er-1.0Zn-0.3Zr合金组织、耐蚀性能和力学性能的影响。结果表明:铸态合金的显微组织主要由α-Mg基体、Mg_(3)Er_(2)Zn_(3)、Mg_(24)Er_(5)和MgErZn_(2)相组成。经固溶处理后,第二相逐渐溶解在镁基体中,且合金平均晶粒尺寸有不同程度的增大。合金经460℃固溶处理8 h后的综合性能较好,其腐蚀速率为(0.44±0.051)mm/y,抗拉强度、屈服强度和伸长率分别为(227.97±4.84)MPa、(137.96±5.03)MPa和(14.42±1.06)%。

关键词： Mg-1.5Er-1.0Zn-0.3Zr合金固溶处理腐蚀性能

Fluorescence Behavior and Emission Mechanisms of Poly(ethylene succinamide)and Its Applications in Fe^(3+)Detection and Data Encryption

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高分子科学：英文版 2023年第1期41卷 129-142页

作者： Xubao Jiang Qinghui Wang Bin Li Shusheng Li xiang zheng Kong College of Chemistry and Chemical Engineering University of JinanJinan250022China Québec Center for Functional Materials Department of ChemistryUniversitéde SherbrookeSherbrookeQCJ1K2R1Canada

Conventional fluorescent polymers are featured by large conjugation *** contrast,a new class of fluorescent polymers without any conjugations is gaining great interest in immerging *** is a typical member of the conjugation-free fluorescent ***,studies on their electrophotonic property are hardly available,although widely used in many ***,poly(ethylene succinamide),PA24,is synthesized;its chemical structure confirmed through multiple techniques(NMR,FTIR,XRD,etc.).PA24 is highly emissive as solid and in its solution at room temperature,and the emission is excitation and concentration dependant,with an unusual blue shift under excitation from 270 nm to 320 nm,a hardly observed phenomenon for all fluorescent *** similar emission behavior is also observed under cryogenic condition at 77 *** emission behavior is thoroughly studied;the ephemeral emission blue-shift is interpreted through Förster resonance energy *** on its structures,the emission mechanism is ascribed to cluster-triggered emission,elucidated from multianalyses(NMR,FTIR,UV absorbance and DLS).In presence of a dozen of competitive metal ions,PA24 emission at 450 nm is selectively quenched by Fe^(3+).PA24 is used as probe for Fe^(3+)and H_(2)O_(2) detections and in data ***,this work provides a novel face of polyamide with great potential applications as sensors in different fields.

关键词： Polyamide Fluorescent emission Cluster formation Ferric ion detection Data encryption

Quantification and timing of porosity evolution in tight sand gas reservoirs:an example from the Middle Jurassic Shaximiao Formation,western Sichuan,China

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Petroleum Science 2015年第2期12卷 207-217页

作者： zheng-xiang Lü Su-Juan Ye xiang Yang Rong Li Yuan-Hua Qing State Key Laboratory of Oil and Gas Reservoir Geology &Exploitation Chengdu University of Technology Exploration and Production Research Institute Sinopec Southwest Chengdu Institute of Geology and Mineral Resources PetroChina Tarim Oilfield Company

The diagenesis and porosity evolution of the Middle Jurassic Shaximiao sandstones were analyzed based on petrographic observations, X-ray diffractometry, scanning electron microscopy observations, carbon and oxygen stable isotope geochemistry, fluid inclusion mi- crothermometry, and thermal and burial history modeling results. The point count data show that secondary pores （av. 5.5 %） are more abundant than primary pores （av. 3.7 %） and are thus the dominant pore type in the Shaximiao sandstones. Analysis of porosity evolution indicates that alteration of sandstones mainly occurred during two paragenetic stages. Mechanical compaction and cementa- tion by early chlorite, calcite, and quartz typically decrease the depositional porosity （40.9 %） by an average of 37.2 %, leaving porosity of 3.7 % after stage I （〈85 ℃, 175-145 Ma）. The original intergranular porosity loss due to compaction is calculated to be 29.3 %, suggesting that mechanical compaction is the most significant diagenetic process in primary porosity destruction. Stage II can be further divided into two sub-stages （Stage IIa and Stage IIb）. Stage IIa （85-120 ℃, 145-125 Ma） is characterized by late dissolution, which enhanced porosity by 8.8 %, and the porosity increased from 3.7 % to 12.5 %. During stage IIb （〉120 ℃, 125-0 Ma）, the precipitation of late chlorite, calcite, quartz, and kaolinite destroyed 3.3 % porosity, leaving porosity of 9.2 % in the rock today.

关键词： Diagenesis Porosity evolution -Tight gas sandstones Jurassic Western Sichuan