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Chemical Research in Chinese Universities 2022年第2期38卷 639-642页

作者： ZHENG Xuhan ZHANG Lin XIE Chenxiao WANG Hui LIU Hui pan Qingyan ZHAO Yingjie College of Polymer Science and Engineering Qingdao University of Science and TechnologyQingdao 266042P.R.China

The isomerization of covalent organic frameworks(COFs) materials is still a mysterious and attractive topic. Diversified monomer structures are still urgently needed to explore the in-depth mechanism of isomerization in these special COFs. This work provides a new D2h monomer for the construction of [D2h+C2] 2D COFs isomers. A new D2h monomer adopted here was proven to tend to form a single pore framework structure.

关键词： Covalent organic framework Isomerization Kagome Dynamic covalent bond

砷在石膏中固定机制:掺杂态和表面吸附沉淀态以及其在砷污染控制中的作用

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地学前缘 2020年第5期27卷 227-237页

作者： Jinru Lin Ning Chen Yuanming pan Department of Geological Sciences University of SaskatchewanSaskatoonSK S7N 5E2Canada Key Laboratory of Pollution Ecology and Environmental Engineering Institute of Applied EcologyChinese Academy of SciencesShenyangLiaoning 110016P.R.China Canadian Light Source University of SaskatchewanSaskatoonSK S7N 0X4Canada

石膏是矿山开采及冶炼等工业过程产生的大宗固体废弃物。工业活动产生的废液普遍有高含量的砷等有毒元素,这导致所产生的石膏也含有较高浓度的砷等有毒元素。研究砷在石膏中地球化学行为和归趋对含砷石膏的砷污染控制具有重要的理论和... 详细信息

石膏是矿山开采及冶炼等工业过程产生的大宗固体废弃物。工业活动产生的废液普遍有高含量的砷等有毒元素,这导致所产生的石膏也含有较高浓度的砷等有毒元素。研究砷在石膏中地球化学行为和归趋对含砷石膏的砷污染控制具有重要的理论和实际意义。然而目前对含砷石膏中不同形态的砷的定量测定和分析尚存在问题。本文在不同pH值的条件下共沉淀砷和石膏,利用电感耦合等离子体质谱(ICP-MS)、同步辐射X-射线吸收近边光谱(XANES)和电子顺磁共振(EPR)对石膏中掺杂态和表面吸附沉淀态的砷进行定量分析。ICP-MS的结果表明随着pH从2升高到12和14,石膏中砷的含量由57×10^-6增加到67470×10^-6和63980×10^-6。同步辐射X-射线吸收近边光谱和电子顺磁共振光谱分析表明石膏样品中主要含有五价砷。在2≤pH≤7.5时,固体样品中同步辐射吸收边后的峰形状和掺杂态砷的形状类似,而在pH≥8时,其边后峰的形状发生明显的变化;粉末电子顺磁共振(EPR)定量分析表明在2≤pH≤7.5时砷在石膏中的含量和ICP-MS的分析结果一致,而在pH≥8时其含量明显小于ICP-MS的分析结果。这些结果揭示了在2≤pH≤7.5时,砷在石膏中主要以掺杂态的形式存在,而在pH≥8时大部分砷是以吸附态或表面沉淀的形式存在。五价砷在石膏中的含量和固定机制随着pH值的变化而变化,其研究对了解尾矿中石膏对砷污染的控制作用具有重要作用。此外,研究石膏中由辐射导致的g约为2.33的[AsO3]^2-自由基电子顺磁共振特征峰,有助于补充和完善石膏的电子顺磁共振特征谱在地质测年及辐射剂量学中的应用。

关键词：石膏矿山尾矿砷污染结构掺杂表面吸附 pH作用

Case-matched comparison of laparoscopy-assisted and open distal gastrectomy for gastric cancer

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World Journal of Gastroenterology 2013年第23期19卷 3672-3677页

作者： Wei Wang Ke Chen Xiao-Wu Xu Yu pan Yi-Ping Mou Department of Gastrointestinal Surgery Shaoxing People's Hospital Shaoxing Hospital of Zhejiang University Department of General Surgery Sir Run Run Shaw Hospital School of Medicine Zhejiang University

AIM: To compare shortand long-term outcomes of laparoscopy-assisted and open distal gastrectomy for gastric cancer. METHODS: A retrospective study was performed by comparing the outcomes of 54 patients who underwent laparoscopy-assisted distal gastrectomy (LADG) with those of 54 patients who underwent open distal gastrectomy (ODG) between October 2004 and October 2007. The patients' demographic data (age and gender), date of surgery, extent of lymphadenectomy, and differentiation and tumor-node-metastasis stage of the tumor were examined. The operative time, intraoperative blood loss, postoperative recovery, complications, pathological findings, and follow-up data were compared between the two ***: The mean operative time was significantly longer in the LADG group than in the ODG group (259.3 ± 46.2 min vs 199.8 ± 40.85 min; P plications were significantly lower (160.2 ± 85.9 mL vs 257.8 ± 151.0 mL; 13.0% vs 24.1%, respectively, P < 0.05). In addition, the time to first flatus, time to initiate oral intake, and postoperative hospital stay were significantly shorter in the LADG group than in the ODG group (3.9 ± 1.4 d vs 4.4 ± 1.5 d; 4.6 ± 1.2 d vs 5.6 ± 2.1 d; and 9.5 ± 2.7 d vs 11.1 ± 4.1 d, respectively; P < 0.05). There was no significant difference between the LADG group and ODG group with regard to the number of harvested lymph nodes. The median followup was 60 mo (range, 5-97 mo). The 1-, 3-, and 5-year disease-free survival rates were 94.3%, 90.2%, and 76.7%, respectively, in the LADG group and 89.5%, 84.7%, and 82.3%, respectively, in the ODG group. The 1-, 3-, and 5-year overall survival rates were 98.0%, 91.9%, and 81.1%, respectively, in the LADG group and 91.5%, 86.9%, and 82.1%, respectively, in the ODG group. There was no significant difference between the two groups with regard to the survival rate. CONCLUSION: LADG is suitable and minimally invasive for treating distal gastric

关键词： Stomach neoplasms Gastrectomy Laparoscopy Survival Case matched study

Dense core vesicle markers in CSF and cortical tissues of patients with Alzheimer’s disease

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Translational Neurodegeneration 2021年第3期10卷 487-501页

作者： Neus Barranco Virginia plá Daniel Alcolea Irene Sánchez‑Domínguez Reiner Fischer‑Colbrie Isidro Ferrer Alberto Lleó Fernando Aguado Department of Cell Biology Physiology and ImmunologyFaculty of BiologyUniversity of Barcelona08028 BarcelonaSpain Institute of Neurosciences University of Barcelona08028 BarcelonaSpain Memory Unit Department of NeurologySant Pau Biomedical Research Institute.Sant Pau HospitalAutonomous University of Barcelona08041 BarcelonaSpain Center for Net‑worked Biomedical Research on Neurodegenerative Diseases(CIBERNED) 28031 MadridSpain Department of Pharmacology Innsbruck Medical University6020 InnsbruckAustria Department of Pathology and Experi‑mental Therapeutics University of Barcelonaand Bellvitge University HospitalBellvitge Biomedical Research InstituteHospitalet de LlobregatSpain Pre‑sent Address:Center for Translational Neuromedicine University of Rochester Medical CenterRochesterNY 14642USA

Background:New fuid biomarkers for Alzheimer’s disease(AD)that reveal synaptic and neural network dysfunc‑tions are needed for clinical practice and therapeutic trial *** core vesicle(DCV)cargos are promising cerebrospinal fuid(CSF)indicators of synaptic failure in AD ***,their value as biomarkers has not yet been ***:Immunoassays were performed to analyze the secretory proteins prohormone convertases PC1/3 and PC2,carboxypeptidase E(CPE),secretogranins SgIII and SgII,and Cystatin C in the cerebral cortex(n=45,provided by Bellvitge University Hospital)and CSF samples(n=66,provided by The Sant Pau Initiative on Neurodegeneration cohort)from AD patients(n=56)and age-matched controls(n=55).Results:In AD tissues,most DCV proteins were aberrantly accumulated in dystrophic neurites and activated astro‑cytes,whereas PC1/3,PC2 and CPE were also specifcally accumulated in hippocampal granulovacuolar degeneration *** individuals displayed an overall decline of secretory proteins in the ***,in AD patients,the CSF levels of prohormone convertases strongly correlated inversely with those of neurodegeneration markers and directly with cognitive impairment ***:These results demonstrate marked alterations of neuronal-specifc prohormone convertases in CSF and cortical tissues of AD *** neuronal DCV cargos are biomarker candidates for synaptic dysfunction and neurodegeneration in AD.

关键词： Alzheimer’s disease Biomarkers Cerebral cortex Cerebrospinal fuid Granulovacuolar degeneration PCSK1 PCSK2 Tau protein

Characterization of a Membrane-Bound O-Acetyltransferase Involved in Trioxacarcin Biosynthesis Offers Insights into Its Catalytic Mechanism

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Chinese Journal of Chemistry 2020年第12期38卷 1607-1611页

作者： Yue Yin Yi Shen Song Meng Mei Zhang Hai-Xue pan Gong-Li Tang State Key Laboratory of Bioorganic and Natural Products Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai 200032China School of Chemistry and Material Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences1 Sub-lane XiangshonHangzhouZhejiang 310024China

of main observation and conclusion Trioxacarcin A(TXN-A)is a polycyclic aromatic natural product with remarkable biological ***11,a membrane-bound O-acetyltransferase involved in TXN-A biosynthesis that is difficult for protein manipulation,is biochemically characterized here for its acetylation function on C4-sugar.A proposed catalytic mechanism is supported by transmembrane helix analysis and site-directed mutagenesis,in which four conserved amino acid residues His35,Ser71,His1OO and His317 are essential for enzyme *** tested the substrate tolerance of TxnB11 to acyl donors in vitro and found that TxnB11 can also utilize propionyl-CoA and glycolyl-CoA,resulting in two new TXN analogs with anti-tumor *** work provides a first understanding of the catalytic mechanism of this unusual acyltransferase family and presents good candidates for creating structural diversity for natural products.

关键词： utilize Catalytic analogs

Effects of Mercuric Chloride on Antioxidant System and DNA Integrity of the Crab Charybdis japonica

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Journal of Ocean University of China 2009年第4期8卷 416-424页

作者： ZHANG Hongxia pan Luqing MIAO Jingjing XU Chaoqun The Key Laboratory of Mariculture Ministry of Education Ocean University of China Qingdao 266003 P. R. China

Mercury （Hg） is one of the commonly encountered heavy metals, which is widespread in inshore sediments of China. In order to investigate the toxicity of Hg on marine invertebrates, we studied the effects of the divalent mercuricion （Hg2＋）（at two final concentrations of 0.0025 and 0.0050mgL-1, prepared with HgC12） on metallothionein （MT） content, DNA integrity （DNA strand breaks） and catalase （CAT） in the gills and hepatopancreas, antioxidant enzyme activities of superoxide dismutase （SOD）, catalase （CAT） and glutathione peroxidase （GPx）, in the hemolymph, gills and hepatopancreas of the portunid crab Chao,bdisjaponica for an experiment period up to 15 d. The results indicated that MT was significantly induced after 3 d, with a positive correlation with Hg2＋ dose and time in the hepatopancreas and a negative correlation with Hg2＋ dose and time in the gills. While CAT in the hemolymph was not detected, it increased in the hepatopancreas during the entire experiment; SOD and GPx in the three tissues were stimulated after 12h, both attained peak value and then reduced during the experimental period. Meanwhile, DNA strand breaks were all induced significantly after 12 h. These results suggested the detoxification strategies against Hg2＋ in three tissues of C. japonica.

关键词： mercury (Hg2+) Charybdisjaponica, metallothionein (MT) antioxidant enzyme DNA strand break

Long-term phosphorus reduction and phytoplankton responses in an urban lake(USA)

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Water Biology and Security 2022年第1期1卷 100-109页

作者： Yuan Grund Yangdong pan Mark Rosenkranz Eugene Foster Oregon Department of Environmental Quality OR97232USA Department of Environmental Science and Management Portland State UniversityPortlandOR97207USA Lake Oswego Corporation Lake OswegoOR97034USA

Eutrophication is one of the primary factors causing harmful cyanobacteria blooms in freshwater *** study investigated the long-term changes in water quality and summer phytoplankton assemblages in Oswego Lake,OR,USA,in relation to phosphorus reduction through hypolimnetic aeration and alum *** water quality and phytoplankton assemblages were sampled biweekly during the summers from 2001 to *** concentrations of total phosphorus,soluble reactive phosphorus,and total nitrogen decreased 66%,93%and 31%,respectively,in response to the hypolimnetic aeration and alum treatments since *** phytoplankton assemblages showed a 62%reduction of cyanobacteria biovolume and a shift from cyanobacteria dominance(2001–2005)to diatom and chlorophyte dominance(2006–2013).Cluster analysis identified four statistically different groups of summer phytoplankton assemblages(denoted Groups 1–4).Nonmetric multidimensional scaling analysis indicated that the four groups were associated with different water quality *** 1 occurred prior to hypolimnetic aeration and was primarily comprised of cyanobacteria,associated with water conditions of high nutrients and high primary *** 2,dominated by cyanobacteria and chlorophytes,occurred between hypolimnetic aeration and alum surface *** 3 was dominated by diatoms and occurred after alum surface *** 4 included R-strategist phytoplankton that quickly respond to environmental changes and occurred in the years following alum injection,drawdown,and inflow alum *** Group 3 and 4 were associated with reduced nutrients in the *** conclude that these lake management practices had strong effects on both production and community compositions of phytoplankton,and advocate for future studies on large-scale climate impacts on lake ecosystems and to identify corresponding best management practices.

关键词： Phosphorus reduction Phytoplankton assemblages Urban lake Long-term species data Harmful algal blooms Alum application Hypolimnetic aeration

Stereocomplexed Materials of Chiral Polymers Tuned by Crystallization:A Case Study on Poly(lactic acid)

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Accounts of Materials Research 2022年第12期3卷 1309-1322页

作者： Ying Zheng Shanshan Xu Chengtao Yu Pengju pan State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China Institute of Zhejiang University-Quzhou Quzhou 324000China

CONSPECTUS:Widespread in chemistry and biochemistry,chirality strongly affects the biological,chemical,material,and physical *** a downstream derivative,the enantiopure polymers of opposite chirality can cocrystallize in the stereocomplex(SC)in their enantiomeric blends or block copolymers,which endows the materials with improved physical properties and specific functions such as enhanced melting temperature,thermal stability,crystallizability,and hydrolytic resistance.

关键词： properties. Chiral blends

An uncertainty analysis of the Newmark displacement model for earthquake-induced landslides in the Jiuzhaigou National Geopark

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Journal of Earth Science 2021年

作者： Guochao Fu Hua pan Jiang Cheng Institute of Geophysics，China Earthquake Administration

In this paper， we present an approach to generating probabilistic hazard maps for earthquake-induced landslides using the Newmark Displacement Model， NDM. This model takes the uncertainties associated with the slope properties （e.g.， soil shear strengths， groundwater table location） into consideration， which is coupled with the hydrological model based on geomorphological， geological， geotechnical， seismological， and rainfall data. Uncertainties and fluctuations in the input parameters of the NDM are considered by treating these quantities as Beta-PERT distributions through Monte Carlo techniques， which allows probability value of the NDM to be cast into hazard maps. Additionally， incorporating Monte Carlo techniques can avoid using conservative input parameters in a deterministic approach to capture these uncertainties. Taking the 2017 Jiuzhaigou Mw 6.5 earthquake in Sichuan Province， Western China as an example， earthquake-induced landslides probability distribution map is generated with the most appropriate displacement threshold （λ=1cm）. Our results show good performances for realistic landslide hazard assessment， which can serve as a basis for providing a reference for the prediction of earthquake-induced landslide probability and rapid landslide hazard assessment after a strong earthquake.

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Polypyrrole random-coil induced permittivity from negative to positive in all-organic composite films

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Journal of Materiomics 2020年第2期6卷 348-354页

作者： Peng Wang Zhongbin pan Mingkun Wang Shuangwu Huang Jinjun Liu Jiwei Zhai School of Materials Science and Chemical Engineering Ningbo UniversityNingboZhejiang315211China School of Materials Science&Engineering Tongji University4800 Caoan RoadShanghai201804China

Percolating composites with negative permittivity can be promising candidates for ***,novel all-organic composite films containing of random coil polypyrrole(PPy)and poly(-vinylidene fluoride)(PVDF)are fabricated via a solution casting *** random coil PPy is prepared by oxidative template assembly approach for the first *** experimental result indicates that the negative permittivity is easily adjusted through controlling the random coil PPy ***,the random coil PPy contents exceeded 7 wt% the negative permittivity appear attributed to the formation of 3D interconnected PPy *** facile approach not only opens a new way to preparing negative permittivity of all-organic composite films,but also points out a route to facilitate the practical applications of metamaterials.

关键词： Polypyrrole Composite films Random coil Negative permittivity