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Pollution characteristics of ambient PM_(2.5)-bound PAHs and NPAHs in a typical winter time period in Taiyuan

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Chinese Chemical Letters 2014年第5期25卷 663-666页

作者： Rui-Jin Li Xiao-Jing Kou Hong Geng Chuan Dong zong-wei cai Institute of Environmental Science Shanxi University State Key Laboratory of Environmental and Biological Analysis Department of ChemistryHong Kong Baptist University

The pollution characteristics of ambient fine particulate matter（PM2.5） containing polycyclic aromatic hydrocarbons（PAHs） and nitrated PAHs（NPAHs） in samples collected during a typical winter time period in Taiyuan of China were *** obtained results revealed that the mean mass concentrations of PM2.5,SPAHs（sum of 16 PAHs） and SNPAHs（sum of 3 NPAHs） on PM2.5were161.4 mg/m3,119.8 ng/m3and 0.446 ng/m3,*** ratios of PAHs and NPAHs implied that coal consumption might be the main source of the *** measured PM2.5mass concentrations,BaP equivalent toxicity（28.632 ng/m3） and individual carcinogenicity index（3.14 10 5） were much higher than those of the recommended safety standards.

关键词： PM2.5 PAHs NPAHs Taiyuan

Identification of in vitro and in vivo metabolites of 12β-hydroxylveratroylzygadenine associated with neurotoxicity by using HPLC–MS/MS

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Chinese Chemical Letters 2014年第8期25卷 1107-1111页

作者： Yue Cong Jing-Gong Guo Zhi Tang Qing-Chun Zhang zong-wei cai Institute of Pharmacy Pharmaceutical College Henan University State Key Laboratory of Environmental and Biological Analysis Department of Chemistry Hong Kong Baptist University The Key Laboratory of Plant Stress Biology Henan University

Metabolism study was carried out on 12b-hydroxylveratroylzygadenine（VOG） that is a cevine-type alkaloid existing in Veratrum nigrum L. and a neurotoxic component. In order to better understand the potential mechanism of neurotoxicity of VOG, this study measured VOG-induced DNA damage in the cerebellum and cerebral cortex of mice after 7 days repetitive oral dose by using single-cell gel electrophoresis（Comet assay）. High performance liquid chromatography-tandem mass spectrometry（LC–MS/MS） was developed and applied to separate and identify in vitro and in vivo metabolites of VOG for investing the possible relationship of metabolism and neurotoxicity. In vitro experiment was carried out using rat liver microsomes, while the in vivo study was conducted on rats. The obtained results indicated that VOG might cause DNA damage in cerebellum and cerebral cortex of mice in a dosedependent manner. Hydrolysis of ester bond and O-demethylation were proposed to be the main in vivo metabolic pathways of VOG, while the major in vitro metabolic pathways were proposed as methyl oxidation to aldehyde, dehydrogenation, hydrolysis of ester bond, hydrolysis of ester bond together with acetylation, and methoxylation. O-Demethylation reaction was likely to be associated with reactive oxygen species production, leading to the DNA damage.

关键词： 12β-Hydroxylveratroylzygadenine Metabolites O-Demethylation LC-MS

Residents'environmental conservation behaviour in the mountain tourism destinations in China:Case studies of Jiuzhaigou and Mount Qingcheng

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山地科学学报（英文） 2017年第12期14卷 2555-2567页

作者： zhang yu-ling zhang jie zhang hong-ou zhang ruo-yang wang yang guo yong-rui wei zong-cai guangzhou institute of geography Guangzhou 510070China guangdong open laboratory of geospatial information technology and application Guangzhou 510070China school of geographic and oceanographic science nanjing universityNanjing 210046China shenzhen tourism college jinan universityShenzhen 518053China school of history culture and tourism jiangsu normal universityJiangsu Normal UniversityXuzhou 221116China school of architecture state key laboratory of subtropical building sciencesouth china university of technologyGuangzhou 510641China

This study aimed at gaining an understanding of the formation of residents' Environmental Conservation Behaviour(ECB) to promote sustainable tourism development in Chinese mountain areas. In particular, a theoretical framework was constructed by merging residents' mountain attachment and their environmental values,and awareness of environmental consequences based on the Cognition Behaviour Theory. This research sampled 642 residents with convenience sampling method in Jiuzhaigou and Mount Qingcheng, and structural equation modelling analysis was conducted to identify the relationships among the above variables. Results verified that mountain attachment affected people's awareness of environmental consequences, which then affected their *** values and mountain attachment directly and positively influenced ECB. Moreover,awareness of environmental consequences played the most prominent role in predicting ECB among all the predictors in this study. In all, this study derived several significant implications which can not only contribute to environmental management policies in tourism field but also help to improve the levels of the antecedents of residents' ECB and promote sustainable tourism development in Chinese mountain areas.

关键词： Sustainable tourism development Mountain attachment Environmental Conservation Behaviour Environmental values Cognitive Behaviour Theory

Design and fabrication of lightweight AlCrFeNiTi_(x) compositionally complex alloys with exceptional specific strength

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Rare Metals 2024年第7期43卷 3314-3328页

作者： Jun-Zhi Li wei-zong Bao Jie Chen Bo-Hua Yu Kun Zuo Tian Gao Ze-Yun cai Guo-Qiang Xie School of Materials Science and Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China

This study focuses on compositionally complex alloys(CCAs),aiming to achieve a balance between high strength and low density for new energy and aerospace *** composition of AlCrFeNiTi_(x) CCAs is strategically guided by employing density functional theory and the theoretical design of thermodynamic *** CCAs,particularly AlCrFeNiTi_(0.25) alloy,demonstrate remarkable specific yield strength(1640.8 MPa) and 22.7% maximum *** incorporation of Ti facilitates the formation of lightweight and high-strength L2_(1)phase,contributing to the overall high specific *** effects of grain boundary strengthening,solid solution strengthening,Orowan strengthening and Peierls flow stress further enhance *** exploration of micros tructural changes during fracture reveals the role of ordered phases in suppressing crack propagation and absorbing energy within disordered phases,thereby improving the toughness and fracture resistance of *** methods and discoveries establish a robust foundation for advancing the development of novel lightweight CCAs.

关键词： Lightweight Compositionally complex alloys Specific yield strength

SOLVING SYSTEMS OF PHASELESS EQUATIONS VIA RIEMANNIAN OPTIMIZATION WITH OPTIMAL SAMPLING COMPLEXITY

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Journal of Computational Mathematics 2024年第3期42卷 755-783页

作者： Jianfeng cai Ke wei Department of Mathematics Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong SARChina School of Data Science Fudan UniversityShanghaiChina

A Riemannian gradient descent algorithm and a truncated variant are presented to solve systems of phaseless equations|Ax|^(2)=*** algorithms are developed by exploiting the inherent low rank structure of the problem based on the embedded manifold of rank-1 positive semidefinite *** recovery guarantee has been established for the truncated variant,showing that the algorithm is able to achieve successful recovery when the number of equations is proportional to the number of *** key ingredients in the analysis are the restricted well conditioned property and the restricted weak correlation property of the associated truncated linear *** evaluations show that our algorithms are competitive with other state-of-the-art first order nonconvex approaches with provable guarantees.

关键词： Phaseless equations Riemannian gradient descent Manifold of rank-1 and positive semidefinite matrices Optimal sampling complexity

Unveiling the secrets of diatom-mediated calcification:Implications for the biological pump

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Science China Earth Sciences 2024年第9期67卷 2895-2909页

作者： Yiwen PAN Yifan LI Chen-Tung Arthur CHEN zong-Pei JIANG wei-Jun cai Yunwen SHEN Zesheng DING Qixian CHEN Yanan DI wei FAN Chenba ZHU Ying CHEN Ocean College Zhejiang UniversityZhoushan 316021China Hainan Institute of Zhejiang University Sanya 570203China Department of Oceanography Sun Yat-Sen UniversityGaoxiong 80424China School of Marine Science and Policy University of DelawareNewark DE 19716USA Carbon Neutral Innovation Research Center Xiamen UniversityXiamen 361005China

Siliceous diatoms are one of the most prominent actors in the oceans,and they account for approximately 40%of the primary production and particulate organic carbon export *** is believed that changes in carbon flux caused by variations in diatom distribution can lead to significant climate *** the fundamental pathways of diatom-driven carbon sequestration have long been established,there are no reports of CaCO_(3) precipitation induced by marine diatom *** manuscript introduces novel details regarding the enhancement of aragonite precipitation during photosynthesis in Skeletonema costatum in both artificial and natural *** direct measurements of cell surfaces via a pH microelectrode and zeta potential analyzer,it was determined that the diatom-mediated promotion of CaCO_(3) precipitation is achieved through the creation of specific microenvironments with concentrated[CO_(3)^(2-)]and[Ca^(2+)]and/or the dehydrating effect of adsorbed Ca^(2+).Based on this mechanism,it is highly plausible that diatom-mediated calcification could occur in the oceans,an assertion that was supported by the significant deviation of total alkalinity(TA)from the conservative TA-salinity mixing line during a Skeletonema costatum bloom in the East China Sea and other similar *** newly discovered calcification pathway establishes a link between particulate inorganic and organic carbon flux and thus helps in the reassessment of marine carbon export fluxes and CO_(2) sequestration *** discovery may have important ramifications for assessing marine carbon cycling and predicting the potential effects of future ocean acidification.

关键词： Diatom bloom Skeletonema costatum Calcification Biological carbon pump Counter carbonate pump

Optimized silicon fertilization regime weakens cadmium translocation and increases its biotransformation in rice tissues

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The Crop Journal 2024年第4期12卷 1041-1053页

作者： Bogui Pan Yixia cai Kunzheng cai Jihui Tian wei Wang College of Natural Resources and Environment South China Agricultural UniversityGuangzhou 510642GuangdongChina Guangdong Provincial Key Laboratory of Eco-Circular Agriculture Guangzhou 510642GuangdongChina Key Laboratory of Tropical Agricultural Environment in South China Ministry of Agriculture and Rural AffairsGuangzhou 510642GuangdongChina College of Agriculture South China Agricultural UniversityGuangzhou 510642GuangdongChina

In acidic paddy fields of South China,rice(Oryza sativa L.)faces the dual challenges of cadmium(Cd)toxicity and silicon(Si)*** previous studies have highlighted the functions of Si application timing and strategies in mitigating Cd-stressed rice,the precise mechanisms underlying the health restoration of Cd-toxic rice and the assurance of grain safety remain *** study explored Cd translocation and detoxification in the shoots of rice regulated by various Si fertilization regimes:Si(T)(all Si added before transplanting),Si(J)(all Si added at jointing),and Si(TJ)(half Si added both before transplanting and at jointing).The findings revealed that the regime of Si(TJ)was more beneficial to rice health and grain safety than Si(T)and Si(J).The osmotic regulators such as proline,soluble sugars,and soluble proteins were significantly boosted by Si(TJ)compared to other Si treatments,and which enhanced membrane integrity,balanced intracellular pH,and increased Cd tolerance of ***,Si(TJ)was more effective than Si(T)and Si(J)on the Cd sequestration in the cell wall,Cd bio-passivation,and the down-regulated expression of the Cd transport *** concentrations of Cd in the xylem and phloem treated with Si(TJ)were reduced ***,Si(TJ)facilitated much more Cd bound with the outer layer proteins of grains,and promoted Cd chelation and complexation by phytic acid,phenolics,and ***,Si(TJ)outperformed Si(T)and Si(J)in harmonizing the phycological processes,inhibiting Cd translocation,and enhancing Cd detoxification in rice *** the split Si application strategy offers potential for reducing Cd toxicity in rice grain.

关键词： Cadmium Silicon Growth stages Translocation and accumulation Rice Safe production

Effectiveness and tolerability of programmed cell death protein-1 inhibitor+chemotherapy compared to chemotherapy for upper gastrointestinal tract cancers

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1613-1625页

作者： Xiao-Min Zhang Ting Yang Ying-Ying Xu Bao-Zhong Li wei Shen Wen-Qing Hu cai-Wen Yan Liang zong Department of Central Laboratory Changzhi People’s HospitalThe Affiliated Hospital of Changzhi Medical CollegeChangzhi 046000Shanxi ProvinceChina Department of Gastrointestinal Surgery Yizheng People’s HospitalThe Affiliated Hospital of Yangzhou UniversityYangzhou 225000Jiangsu ProvinceChina Department of General Surgery Anyang Tumor HospitalAnyang 455000Henan ProvinceChina Department of General Surgery Wuxi People’s Hospital Affiliated to Nanjing Medical UniversityWuxi 214023Jiangsu ProvinceChina Department of Gastrointestinal Surgery Changzhi People’s HospitalThe Affiliated Hospital of Changzhi Medical CollegeChangzhi 046000Shanxi ProvinceChina Department of Gastroenterology Changzhi People’s HospitalThe Affiliated Hospital of Changzhi Medical CollegeChangzhi 046000Shanxi ProvinceChina

BACKGROUND The combination of programmed cell death protein-1(PD-1)inhibitor and che-motherapy is approved as a standard first-or second-line treatment in patients with advanced oesophageal or gastric ***,it is unclear whether this combination is superior to chemotherapy *** To assess the comparative effectiveness and tolerability of combining PD-1 inhibitors with chemotherapy vs chemotherapy alone in patients with advanced gastric cancer,gastroesophageal junction(GEJ)cancer,or oesophageal *** We searched the PubMed and Embase databases for studies that compared the efficacy and tolerance of PD-1 inhibitors in combination with chemotherapy vs chemotherapy alone in patients with advanced oesophageal or gastric *** employed either random or fixed models to analyze the outcomes of each clinical trial,en-compassing data on overall survival(OS),progression-free survival(PFS),objective response rate,and adverse events(AEs).RESULTS Nine phase 3 clinical trials(7016 advanced oesophageal and gastric cancer patients)met the inclusion *** meta-analysis demonstrated that the pooled PD-1 inhibitor+chemotherapy group had a significantly longer OS than the chemotherapy-alone group[hazard ratio(HR)=0.76,95%confidence interval(CI):0.71-0.81];the pooled PFS result was consistent with that of OS(HR=0.67,95%CI:0.61-0.74).The count of patients achieving an objective response in the PD-1 inhibitor+chemotherapy group surpassed that of the chemotherapy-alone group[odds ratio(OR)=1.86,95%CI:1.59-2.18].AE incidence was also higher in the combination-therapy group than in the chemotherapy-alone group,regardless of whether≥grade 3 only(OR=1.30,95%CI:1.07-1.57)or all AE grades(OR=1.88,95%CI:1.39-2.54)were *** performed a subgroup analysis based on the programmed death-ligand 1(PD-L1)combined positive score(CPS)and noted extended OS and PFS durations within the CPS≥1,CPS≥5,and CPS≥10 subgroups of the PD-1 inhibitor+chemotherapy ***

关键词： Programmed cell death protein-1 inhibitor Chemotherapy Oesophageal squamous cell carcinoma Gastric/gastroesophageal junction adenocarcinoma Overall survival Progression-free survival Objective response rate Adverse event

Limits of Uneven Battery Power in Modular Multilevel Converter-based Battery Energy Storage Systems

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 686-695页

作者： Yao Pan Xiaofeng Sun wei Zhao Xin Li Yao cai Institute of Electrical Engineering Yanshan UniversityQinhuangdao 066004China

For modular multilevel converter-based battery energy storage systems (MMC-BESS), uneven power among batteries of SMs will be deduced by battery aging, battery fault, etc., which will degrade performance and even lead to system failure. For maintaining the balance of capacitor voltage, this paper analyzes the limits of the uneven power of batteries, which are presented as the current limits in this paper. According to analysis, an analytical method is proposed that only the dc and fundamental frequency components of the arm current are used to calculate current limits. With the current limits it is able to evaluate the reasonability of power distribution among batteries. Meanwhile, increase of fundamental frequency component will enhance the current limits, and the dc component determines the size relationship between the absolute values of the upper and lower current limits. Finally, simulation model and experiment prototype are built for verifying the theoretical analysis and current limits calculation method, and satisfactory results are provided.

关键词： Arm current balance of capacitor voltage current limits MMC-BESS uneven power