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Effect of shrub encroachment on leaf nutrient resorption in temperate wetlands in the Sanjiang Plain of Northeast China

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Ecological Processes 2022年第1期11卷 968-975页

作者： le‑lin Yu Xin‑Hou Zhang Fu‑Xi Shi Rong Mao Key Laboratory of National Forestry and Grassland Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed College of ForestryJiangxi Agricultural UniversityNo.1101 Zhimin RoadNanchang 330045China Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China School of Environment Nanjing Normal UniversityNanjing 210046China

Background:Nutrient resorption is an important plant nutrient conservation strategy in ***,how shrub encroachment alters plant nutrient resorption processes is unclear in temperate ***,we collected green and senesced leaves of common sedge,grass,and shrub species in wetlands with high(50–65%)and low(20–35%)shrub covers in the Sanjiang Plain of Northeast China,and assessed the impact of shrub encroachment on leaf nitrogen(N)and phosphorus(P)resorption efficiency and proficiency at both plant growth form and community ***:The effects of shrub cover on leaf nutrient resorption efficiency and proficiency were identical among shrubs,grasses,and *** of plant growth forms,increased shrub cover reduced leaf N resorption efficiency and proficiency,but did not alter leaf P resorption efficiency and ***,the effect of shrub cover on leaf nutrient resorption efficiency and proficiency differed between plant growth form and community *** the community level,leaf N and P resorption efficiency decreased with increasing shrub cover because of increased dominance of shrubs with lower leaf nutrient resorption efficiency over grasses and ***,community‑level senesced leaf N and P concentrations increased with elevating shrub cover,showing a decline in leaf N and P resorption ***,the significant relationships between leaf nutrient resorption efficiency and proficiency indicate that shrub encroachment increased senesced leaf nutrient concentrations by decreasing nutrient resorption ***:These observations suggest that shrub encroachment reduces community‑level leaf nutrient resorp‑tion efficiency and proficiency and highlight that the effect of altered plant composition on leaf nutrient resorption should be assessed at the community level in temperate wetlands.

关键词： Biodiversity Freshwater marsh Nutrient conservation strategy Plant growth form Species composition

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Boosting CO_(2) electroreduction to formate via bismuth oxide clusters

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Nano Research 2023年第10期16卷 12050-12057页

作者： Xiaole Jiang le lin Youwen Rong Rongtan Li Qike Jiang Yaoyue Yang Dunfeng Gao Key Laboratory of Fundamental Chemistry of the State Ethnic Commission School of Chemistry and EnvironmentSouthwest Minzu UniversityChengdu 610041China State Key Laboratory of Catalysis Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China School of Science Dalian Maritime UniversityDalian 116026China University of Chinese Academy of Sciences Beijing 100049China

Supported metal(oxide)clusters,with both rich surface sites and high atom utilization efficiency,have shown improved activity and selectivity for many catalytic reactions over nanoparticle and single atom ***,the role of cluster catalysts has been rarely reported in CO_(2)electroreduction reaction(CO_(2)RR),which is a promising route for converting CO_(2)to liquid fuels like formic acid with renewable *** we develop a bismuth oxide(BiOn)cluster catalyst for highly efficient CO_(2)RR to *** BiOn cluster catalyst exhibits excellent activity,selectivity,and stability towards formate production,with a formate Faradaic efficiency of over 90%at a current density up to 500 mA·cm^(−2)in an alkaline membrane electrode assembly electrolyzer,corresponding to a mass activity as high as 3,750 A·gBi−*** electrolyzer with the BiOn cluster catalyst delivers a remarkable formate production rate of 0.56 mmol·min−1 at a high single-pass CO_(2)conversion of 44%.Density functional theory calculations indicate that Bi4O_(3)cluster is more favorable for stabilizing the HCOO^(*)intermediate than Bi(001)surface and single site BiC_(4)motif,rationalizing the improved formate production over the BiOn cluster *** work highlights the great importance of cluster catalysts in activity and selectivity control in electrocatalytic CO_(2)conversion.

关键词： CO_(2)electroreduction reaction formate bismuth oxide cluster catalyst membrane electrode assembly

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Cracking behaviors and strength of rock-like samples with steps of different geometries under shear stress

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Journal of Mountain Science 2021年第5期18卷 1352-1370页

作者： le Hui-lin WEI Ji-hong SUN Shao-rui ZHANG Chu-chu Department of Geology Engineering Hohai UniversityNanjing 210098China China Energy Engineering Group Jiangsu Power Design Institute Co. Ltd.Nanjing 210098China

Steps are distinctive features for estimating the movement of the upper and lower block of ***,studies about the influence of steps as a special type of discontinuity on cracking behaviors and strength of rock masses are *** this research,rock-like samples with steps and preexisting flaws were *** height h and the inclination angle of gentle slope of the stepαwere set to different *** shear tests were conducted on these samples under different normal *** experimental results reveal that the inclination angle of the gentle slope of the stepα,step height h,and normal stress have an influence on the strength,crack initiation,and crack propagation of the *** experimental results show that crack behaviors and shear strength were affected by step inclination anglesαand step height *** the normal stress increases,the improvement of the strength of samples with a large step height is larger than that of samples with a small step height,the improvement of the strength of samples withαof 10°is larger than that of samples withαof 0°and-10°.The discrete element method was used to simulate the shear *** results show five different types of displacement vectors,which can be used to determine whether the cracks are tensile cracks or shear *** above conclusions can provide help for estimating mechanical properties and failure modes of rock masses with steps of different geometries.

关键词： Step Preexisting flaw Direct shear test Crack behavior Shear stress Numerical test

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Synergistic effect of all-trans-ret inoic acid and arsenic trioxide on growth inhibition and apoptosis in human hepatoma, breast cancer, and lung cancer cells in vitro

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World Journal of Gastroenterology 2005年第36期11卷 5633-5637页

作者： le-Min lin Bao-Xin Li Jian-Bing Xiao Dan-Hua lin Bao-Feng Yang Department of General Surgery The First ClinicalCollege Harbin Medical University Harbin 150001 Heilongjiang Province China Department of Pharmacology Harbin Medical University Harbin150086 Heilongjiang Province China

AIM： To investigate the effect of all-trans-retinoic acid （ATRA） on arsenic trioxide （As2O3）-induced apoptosis of human hepatoma, breast cancer, and lung cancer cells in an attempt to find a better combination therapy for solid tumors. METHODS： Human hepatoma cell lines HepG2, Hep3B, human breast cancer cell line MCF-7, and human lung adenocarcinoma cell line AGZY-83-a were treated with As203 together with ATRA. Cell survival fraction was determined by MTT assay, cell viability and apoptosis were measured by annexin V-fluorescein isothiocyanate （FITC） and PI staining, and intracellular glutathione （GSH） and glutathione-S-transferase （GST） activities were determined using commercial kits. RESULTS： Cytotoxicity of ATRA was low. ATRA （0.1, 1, and 10 μmol/L） could synergistically potentiate As2O3 to exert a dose-dependent inhibition of growth and to induce apoptosis in each of the cell lines. HepG2 and Hep3B with low intracellular GSH or GST activities were remarkably sensitive to As2O3 or As2O3＋ATRA, while AGZY-83-a with higher GSH or GST activities was less sensitive to As2O3 or As2O3＋ATRA. Treatment with 2 μmol/L As2O3 for 72 h significantly decreased intracellular GSH and GST levels in each of the cell lines, and 1 μmol/L ATRA alone reduced minimal intracellular GSH and GST levels. ATRA potentiated the effect of As2O3 on intracellular GSH levels, but intracellular GST levels were not significantly affected by the combination of As2O3 and ATRA for 72 h as compared to As2O3 ***： ATRA can strongly potentiate As2O3- induced growth-inhibition and apoptosis in each of the cell lines, and two drugs can produce a significant synergic effect. The sensitivity to As2O3 or As2O3＋ATRA is inversely proportional to intracellular GSH or GST levels in each of the cell lines. The GSH redox system may be the possible mechanism by which ATRA synergistically potentiates As203 to exert a dose-dependent inhibition of growth and to induce apoptosis. 2005 The WJG Press and Els

关键词： Arsenic trioxide AII-trans-retinoic acid Hepatocellular carcinoma Cancer of breast and lung Glutathione Glutathione-S-tra nsferase

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Full-thickness excision using transanal endoscopic microsurgery for treatment of rectal neuroendocrine tumors

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World Journal of Gastroenterology 2015年第30期21卷 9142-9149页

作者： Wei-Jie Chen Nan Wu Jiao-lin Zhou Guo-le lin Hui-Zhong Qiu Department of Surgery Peking Union Medical College HospitalPeking Union Medical College and Chinese Academy of Medical Sciences

AIM:To assess the efficacy of full-thickness excision using transanal endoscopic microsurgery(TEM) in the treatment of rectal neuroendocrine ***:We analyzed the data of all rectal neuroendocrine tumor patients who underwent local full-thickness excision using TEM between December 2006 and December 2014 at our department. Data collected included patient demographics,tumor characteristics,operative details,postoperative outcomes,pathologic findings,and follow-ups. RESULTS:Full-thickness excision using TEM was performed as a primary excision(n = 38) or as complete surgery after incomplete resection by endoscopic polypectomy(n = 21). The mean size of a primary tumor was 0.96 ± 0.21 cm,and the mean distance of the tumor from the anal verge was 8.4 ± 1.4 cm. The mean duration of the operation was 57.6 ± 13.7 min,and the mean blood loss was 13.5 ± 6.6 m L. No minor morbidities,transient fecal incontinence,or wound dehiscence was found. Histopathologically,all tumors showed typical histology without lymphatic or vessel infiltration,and both deep and lateral surgical margins were completely free of tumors. Among 21 cases of complete surgery after endoscopic polypectomy,9 were histologically shown to have a residual tumor in the specimens obtained by TEM. No additional radical surgery was performed. Norecurrence was noted during the median of 3 years' ***:Full-thickness excision using TEM could be a first surgical option for complete removal of upper small rectal neuroendocrine tumors.

关键词： Transanal endoscopic microsurgery Rectalneuroendocrine tumor Full-thickness excision Primaryexcision Complete excision Retrospective study

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Independent directors' board networks and controlling shareholders' tunneling behaviorq

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China Journal of Accounting Research 2014年第2期7卷 101-118页

作者： Yunsen Chen Yutao Wang le lin School of Accountancy Central University of Finance and EconomicsChina School of Economics and Management Tsinghua UniversityChina

As one of the channels by which board directors build important relationships,board networks can affect the governance role of independent directors. Defining director board networks as their connections based on direct ties they establish when serving on at least one common board, this paper explores the role of the network centrality of independent directors in restraining tunneling behavior by controlling shareholders in the Chinese capital *** empirical evidence shows that tunneling behavior by controlling shareholders is negatively related to the network centrality of independent directors and that this relationship is stronger when non-operating fund occupation is used as the measure of tunneling. The results of our study show that board networks can help independent directors to restrain tunneling behavior by large shareholders, which plays a positive role in corporate governance.ó 2013 Production and hosting by Elsevier B.V. on behalf of China Journal of Accounting Research. Founded by Sun Yat-sen University and City University of Hong Kong.

关键词： Network Independent director Tunneling Socialnetwork analysis

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Spectroscopic and Structural Study of the 1:2 Aluminium(III) Complex of Quercetin

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Chinese Chemical letters 2006年第7期17卷 937-940页

作者： Tian le lin Bao Zhen YAN Gao Fei HU Mei WANG School of Science Beijing University of Chemical Technology Beijing 100029

Complex formation between aluminium and quercetin（Q） in methanol was investigated by means of 27^Al solid-state, 13^C and 1^H NMR and MS（ESI）, UV and IR spectra. Formation of the 1：2 complex was favored in methanol relative to all other solvent and the predominant species observed of Al（Ⅲ） has a 1：2 stoichiometry. The fine structure of 1：2 aluminum complex of quercetin was that the aluminum central atom chelated with two quereetin molecules and two methoxyl groups between two five membered rings, its coordination is six, the chelated site was 3-hydroxy-4-carbonyl.

关键词： Quercetin Al(Ⅲ) complexation stoichiometry NMR.

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Effects of water adsorption on active site-dependent H_(2)activation over MgO nanoflakes

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Nano Research 2023年第7期16卷 9059-9064页

作者： Aiyi Dong Kun Li Rentao Mu Conghui Liu Rongtan Li Haoran Jia le lin Qiang Fu School of Science Dalian Maritime UniversityDalian 116026China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Understanding the effect of H_(2)O adsorption on reactant activation is of great importance in heterogeneous catalysis,which remains a grand challenge particularly in oxide catalyst systems with structural ***,the effect of D_(2)O adsorption on D_(2)activation over MgO nanocatalysts at different temperatures has been investigated by transmission Fourier transform infrared(FT-IR)and temperature-programmed desorption(TPD).Two sets of hydride and hydroxyl species produced from D_(2)dissociation at more active and less active Mg-O pairs can be observed by FT-IR,which all desorb via the product of D_(2)as confirmed by TPD *** find that the physically adsorbed D_(2)O overlayer does not affect the dissociation of D_(2)since D_(2)may pass through the molecular layer and access the surface-active *** D_(2)O is partially dissociated on the MgO surface,D_(2)can only dissociate at the remaining active sites until that dissociated-ODw groups from D_(2)O occupy all active *** findings provide a fundamental understanding of the effect of water adsorption on D_(2)activation on oxide catalysts.

关键词： H_(2)activation MgO hydride hydroxyl H_(2)O

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Extraction of Cr(Ⅵ) from chromite ore processing residue via hydrothermal-assisted phase transformation

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Chinese Chemical letters 2020年第7期31卷 1956-1960页

作者： Xiaofeng Mo Jin Zhou le lin Zuqi Zhong Shaohua Yang Xueming Liu Zhenqing Shi Dongye Zhao Zhang lin The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters(Ministry of Education) School of Environment and EnergySouth China University of TechnologyGuangzhou 510006China Sino-Singapore International Joint Research Institute Sino-Singapore Guangzhou Knowledge CityGuangzhou 510006China Environmental Engineering Program Department of Civil EngineeringAuburn UniversityAuburn AL 36849United States

The effective extracting Cr(Ⅵ) from chromite ore processing residue(COPR) is the key to achieve COPR detoxification and *** developed an effective method to extract Cr(Ⅵ) from COPR via controlling the phase transformation of Cr(Ⅵ)-containing *** analysis showed that Cr(Ⅵ) was mainly incorporated in the hydrocalumite(NaCa4Al2O6(SO4/CrO4)1.5-15H2O) in COPR,which was a layered-double hydroxide(LDH) with multilayer *** the hydrothermal treatment experiments,the Na2CO3 solution showed significant extraction effect of Cr(Ⅵ) and detoxification effect of *** treatment,95% of Cr(Ⅵ) was removed and the Cr(Ⅵ) concentration in the leachate was decreased to 1.6 mg/L by the toxicity characteristic leaching procedure(TCLP),within the regulatory limit disposal standard(HJ/T 301-2007,3 mg/L).Further study revealed that,during the treatment,hydrocalumite transformed into calcite(CaCO3) under the effect of mineralizer,therefore,the layered structure collapsed and the incorporated Cr(Ⅵ) was released to the ***,the Cr(Ⅵ)desorbed from calcite with the calcite particles grew into large size with smooth ***-flow experiment revealed that the amount of chromium released from CORP to the environment was significantly reduced after treatment,and it is safer for landfill *** work will provide an instructive guidance for the detoxification and recovery of COPR.

关键词： Chromite ore processing residue Hexavalent chromium extraction Hydrothermal mineralization Phase transformation

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Resection of multiple rectal carcinoids with transanal endoscopic microsurgery:Case report

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World Journal of Gastroenterology 2015年第7期21卷 2220-2224页

作者： Jiao-lin Zhou Guo-le lin Da-Chun Zhao Guang-Xi Zhong Hui-Zhong Qiu Department of General Surgery Peking Union Medical College Hospital Department of Pathology Peking Union Medical College Hospital Department of Ultrasound Peking Union Medical College Hospital

Multiple rectal carcinoids are *** to the unreliability of endoscopic polypectomy in treating these submucosal lesions,a laparotomy is usually *** present a case report on multiple rectal carcinoids with three carcinoid focilesions to be confined to the submucosal layer with no perirectal nodal involvement.A transanal endoscopic microsurgerywas successfully performed to remove the three lesions with accurate full-thickness resection followed by secured suture *** postoperative pathology revealed neuroendocrine tumors G1(carcinoids)located within the submucosal layer without lymphatic or vessel *** the deep and lateral surgical margins were completely free of tumor *** patient recovered quickly and *** tumor recurrence was observed at the six-month *** the multiple small rectal carcinoids without muscularis propria or lymphatic invasion,transanal endoscopic microsurgery offers a reliable and efficient alternative approach to traditional laparotomy for select patients,with the added advantages of minimally invasive surgery.

关键词： Colorectal Gastrointestinal surgery Oncological su

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