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Zwitterionic ring-opening polymerization of macrocyclic ethyleneoxy-substituted carbonate:Access to cyclic PEG-like polycarbonate

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Chinese Chemical Letters 2024年第3期35卷 282-286页

作者： Jin Huang Jinwen Li Rui Yan Yuanyuan Qu Fengzhen Guo Lei Shen Can-liang Ma Jie Sun Zhenjiang Li Kai Guo State Key Laboratory of Materials-Oriented Chemical Engineering College of Biotechnology and Pharmaceutical EngineeringNanjing Tech UniversityNanjing 211816China institute of Nanjing Advanced Biomaterials&Processing Equipment Lishui Economic Development ZoneNanjing 211299China

The innovation in polymer design to rival conventional polyethylene glycol(PEG)is an important approach to achieving a more sustainable society.Here,cyclic PEG-like polycarbonates having high molecular weight(4.4–49.5 kg/mol)were enabled through zwitterionic ring-opening polymerization(ZROP)of macrocyclic carbonates(MCs)mediated by N-heterocyclic carbene(NHC).The thermodynamic behavior of polymerization depends on the ring size of monomers.During this process,the ZROP of 11-membered MC was driven by the change of enthalpy(ΔH_(p))which differed from the ZROP of 14-membered MC driven by the entropic change(ΔS_(p)).Cyclic polycarbonates depicted improved thermostability(T_(d5%)≥204℃)and higher glass transition temperatures(T_(g)>–40℃)in comparison to their linear analogues(T_(d5%)≤185℃,T_(g)~–50℃).In addition,the mechanism of ZROP of MC was addressed through computational study.A distinct mechanism of polymerization distinguishable from the well-known NHC-mediated ZROP of cyclic esters was revealed,where the zwitterion from nucleophilic addition to MC,i.***.tetrahedral intermediate,cannot be ring-opened probably due to the delocalization of negative charge on the carbonate group,but serves as an active center for the polymerization.In comparison to PEG,the attained polymer demonstrated comparable hydrophilic and biocompatible properties,as revealed by the results of contact angle and in vitro cytotoxicity studies,suggesting that cyclic polycarbonate hold the promise as the alternative of PEG.

关键词： Zwitterionic ring-opening polymerization Cyclic polycarbonate Macrocycles Tetrahedral intermediate NHC carbene

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Promoting grain production through high-standard farmland construction:Evidence in china

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Journal of Integrative Agriculture 2024年第1期23卷 324-335页

作者： Shuai Hao Guogang Wang Yantao Yang Sicheng Zhao Shengnan Huang Liping Liu Huanhuan Zhang institute of Agricultural economics and development Chinese Academy of Agricultural SciencesBeijing 100081China

Food security is a strategic priority for a country’s economic development.In china,high-standard farmland construction(HSFC)is an important initiative to stabilize grain production and increase grain production capacity.Based on panel data from 31 sample provinces,autonomous regions,and municipalities in china from 2005–2017,this study explored the impact of HSFC on grain yield using the difference-in-differences(DID)method.The results showed that HSFC significantly increased total grain production,which is robust to various checks.HSFC increased grain yield through three potential mechanisms.First,it could increase the grain replanting index.Second,it could effectively reduce yield loss due to droughts and floods.Last,HSFC could strengthen the cultivated land by renovating the low-and medium-yielding fields.Heterogeneity analysis found that the HSFC farmland showed a significant increase in grain yield only in the main grain-producing areas and balanced areas.In addition,HSFC significantly increased the yields of rice,wheat,and maize while leading to a reduction in soybean yields.The findings suggest the government should continue to promote HSFC,improve construction standards,and strictly control the“non-agriculturalization”and“non-coordination”of farmland to increase grain production further.At the same time,market mechanisms should be used to incentivize soybean farming,improve returns and stabilize soybean yields.

关键词： high-standard farmland farmland construction food security food production area difference-in-differences

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Spatial-temporal shifting patterns and in situ conservation of spotted seal(Phoca largha)populations in the Yellow Sea ecoregion

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Integrative Zoology 2024年第2期19卷 307-318页

作者： Hongfei ZHUANG Fei SHAO Chao ZHANG Wancai XIA Shouqiang WANG Fangyuan QU Zongling WANG Zhichuang LU Linlin ZHAO Zhaohui ZHANG First institute of Oceanography Ministry of Natural ResourcesQingdaoChina Department of Natural Resources of Shandong Province Shandong Forestry Protection and Development Service CenterJinanChina National Park(Protected Areas)development Center National Forestry and Grassland AdministrationBeijingChina College of Life Science China West Normal UniversityNanchongChina Liaoning Ocean and Fisheries Science Research institute DalianChina

Understanding the habitat shifting pattern is a prerequisite for implementing in situ conservation of migratory species.Spotted seals(Phoca largha)inhabiting the Yellow Sea ecoregion(YSE)comprise a small population with independent genes and represent a charismatic flagship species in this region.However,this population has declined by 80%since the 1940s,and increased support from the countries around the YSE is urgently needed to address the potential local extinction risk.A time-series niche model and life-history weighted systematic conservation planning were designed on the basis of a satellite beacon tracking survey(2010–2020)of the YSE population.The results showed clustering and spreading shifting patterns during the breeding and migratory seasons,respectively.The closed-loop migration route formed in the YSE indicated that this population might be geographically isolated from populations in other breeding areas around the world.The conservation priority area(CPA),with an area of 19632 km^(2)(3.58%of the total YSE area),was the most effective response to the potential in situ risk.However,nearly 80%of the CPA was exposed outside the existing marine protected areas(MPAs).Future establishment of MPAs in china should strategically consider the conservation gap identified herein,and it is recommended for Korea’s closed fishing season to be spatially set in the western Korean Peninsula from May to August.This study also exemplified that the lack of temporal information would lead to the dislocation of niche modeling for migratory species represented by spotted seals.Attention should be paid to protecting small and migratory populations in marine biodiversity conservation planning.

关键词： conservation priority area marine protected area migration seasonal management spotted seal

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Industrial Carbon Emission Distribution and Regional Joint Emission Reduction:A Case Study of Cities in the Pearl River Basin,china

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Chinese Geographical Science 2024年第2期34卷 210-229页

作者： JIANG Hongtao YIN Jian ZHANG Bin WEI Danqi LUO Xinyuan DING Yi XIA Ruici Center for western china Modernization Guizhou University of Finance and EconomicsGuiyang 550025China College of Big Data Application and economic Guizhou University of Finance and EconomicsGuiyang 550025China Key Laboratory of Green Fintech Guizhou University of Finance and EconomicsGuiyang 550025China

china’s low-carbon development path will make significant contributions to achieving global sustainable development goals.Due to the diverse natural and economic conditions across different regions in china,there exists an imbalance in the distribution of car-bon emissions.Therefore,regional cooperation serves as an effective means to attain low-carbon development.This study examined the pattern of carbon emissions and proposed a potential joint emission reduction strategy by utilizing the industrial carbon emission intens-ity(ICEI)as a crucial factor.We utilized social network analysis and Local Indicators of Spatial Association(LISA)space-time trans-ition matrix to investigate the spatiotemporal connections and discrepancies of ICEI in the cities of the Pearl River Basin(PRB),china from 2010 to 2020.The primary drivers of the ICEI were determined through geographical detectors and multi-scale geographically weighted regression.The results were as follows:1)the overall ICEI in the Pearl River Basin is showing a downward trend,and there is a significant spatial imbalance.2)There are numerous network connections between cities regarding the ICEI,but the network structure is relatively fragile and unstable.3)economically developed cities such as Guangzhou,Foshan,and Dongguan are in the center of the network while playing an intermediary role.4)Energy consumption,industrialization,per capita GDP,urbanization,science and techno-logy,and productivity are found to be the most influential variables in the spatial differentiation of ICEI,and their combination in-creased the explanatory power of the geographic variation of ICEI.Finally,through the analysis of differences and connections in urban carbon emissions under different economic levels and ICEI,the study suggests joint carbon reduction strategies,which are centered on carbon transfer,financial support,and technological assistance among cities.

关键词： industrial carbon emission intensity carbon emission social network analysis Location Indicators of Spatial Association(LISA) geographical detector multi-scale geographically weighted regression Pearl River Basin(PRB),china

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A novel FGFR1 inhibitor CYY292 suppresses tumor progression,invasion,and metastasis of glioblastoma by inhibiting the Akt/GSK3β/snail signaling axis

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Genes & Diseases 2024年第1期11卷 479-494页

作者： Yanran Bi Ruiling Zheng Jiahao Hu Ruiqing Shi Junfeng Shi Yutao Wang Peng Wang Wenyi Jiang Gyudong Kim Zhiguo Liu Xiaokun Li Li Lin School of Pharmaceutical Science Wenzhou Medical UniversityWenzhouZhejiang 325035China College of Pharmacy and Research institute of Drug development Chonnam National UniversityGwangju 61186Republic of Korea Department of Dermatology Wenzhou Hospital of Integrated Traditional Chinese and Western MedicineWenzhouZhejiang 325000China Zhejiang Lab for Regenerative Medicine Oujiang LaboratoryWenzhouZhejiang 325035China

Glioblastoma(GBM)is a malignant brain tumor that grows quickly,spreads widely,and is resistant to treatment.Fibroblast growth factor receptor(FGFR)1 is a receptor tyrosine kinase that regulates cellular processes,including proliferation,survival,migration,and dif-ferentiation.FGFR1 was predominantly expressed in GBM tissues,and FGFR1 expression was negatively correlated with overall survival.We rationally designed a novel small molecule CYY292,which exhibited a strong affinity for the FGFR1 protein in GBM cell lines in vitro.CYY292 also exerted an effect on the conserved Ser777 residue of FGFR1.CYY292 dose-depen-dently inhibited cell proliferation,epithelial-mesenchymal transition,stemness,invasion,and migration in vitro by specifically targeting the FGFR1/AKT/Snail pathways in GBM cells,and this effect was prevented by pharmacological inhibitors and critical gene knockdown.In vivo experiments revealed that CYY292 inhibited U87MG tumor growth more effectively than AZD4547.CYY292 also efficiently reduced GBM cell proliferation and increased survival in orthotopic GBM models.This study further elucidates the function of FGFR1 in the GBM and reveals the effect of CYY292,which targets FGFR1,on downstream signaling pathways directly reducing GBM cell growth,invasion,and metastasis and thus impairing the recruitment,activation,and function of immune cells.

关键词： Blood-brain barrier EMT FGFR1 FGFR1 inhibitor Glioblastoma

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Identification and characterization of camptothecin tailoring enzymes in Nothapodytes tomentosa

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Journal of Integrative Plant Biology 2024年第6期66卷 1158-1169页

作者： Yin Chen Jian-Ping Huang Yong-Jiang Wang Meng-Ling Tu Junheng Li Bingyan Xu Guoqing Peng Jing Yang Sheng-Xiong Huang State Key Laboratory of Phytochemistry and Plant Resources in West china and Yunnan Key Laboratory of Natural Medicinal Chemistry Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for economic Plants and Biotechnology Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China

Camptothecin is a complex monoterpenoid indole alkaloid with remarkable antitumor activity.Given that two C-10 modified camptothecin derivatives,topotecan and irinotecan,have been approved as potent anticancer agents,there is a critical need for methods to access other aromatic ringfunctionalized congeners(e.g.,C-9,C-10,etc.).However,contemporary methods for chemical oxidation are generally harsh and low-yielding when applied to the camptothecin scaffold,thereby limiting the development of modified derivatives.Reported herein,we have identified four tailoring enzymes responsible for C-9 modifications of camptothecin from Nothapodytes tomentosa,via metabolomic and transcriptomic analysis.These consist of a cytochrome P450(Nt CPT9H)which catalyzes the regioselective oxidation of camptothecin to 9-hydroxycamptothecin,as well as two methyltransferases(Nt OMT1/2,converting 9-hydroxycamptothecin to 9-methoxycamptothecin),and a uridine diphosphate-glycosyltransferase(Nt UGT5,decorating 9-hydroxycamptothecin to9-β-D-glucosyloxycamptothecin).Importantly,the critical residues that contribute to the specific catalytic activity of Nt CPT9H have been elucidated through molecular docking and mutagenesis experiments.This work provides a genetic basis for producing camptothecin derivatives through metabolic engineering.This will hasten the discovery of novel C-9 modified camptothecin derivatives,with profound implications for pharmaceutical manufacture.

关键词： camptothecin biosynthesis enzymatic assay Nothapodytes tomentosa tailoring enzyme transcriptomic analysis

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Understanding livelihood vulnerability:a perspective from western Sichuan’s ethnic rural settings

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Journal of Mountain Science 2024年第2期21卷 380-396页

作者： YU Yongqian JING Zheng WANG Yan QIU Xiaoping YANG Xueting XU Yun School of Geography and Resource Science Sichuan Normal UniversityChengdu 610101China Key Laboratory of land Resources Evaluation and Monitoring in Southwest Ministry of EducationSichuan Normal UniversityChengdu 610101China Sichuan County economic development Research Center Mianyang Normal UniversityMianyang 621000China institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China

To explore the livelihood status and key influencing factors of rural households in the minority areas,we collected flat data from 284 rural households in 32 villages across 12 counties of western Sichuan from 2021 to 2022.We conducted participatory household survey on the livelihood status of the rural households and try to identify the key factors to influence their livelihood vulnerability using multiple linear regression.The results showed that:the livelihood situation of the rural households is relatively vulnerable.The vulnerability varies significantly with the income levels,education levels,and income sources.The vulnerability of farm households,categorized from low to high livelihood types,follows the sequence:non-agricultural dominant households,non-agricultural households,agricultural dominant households,and pure agricultural households.The degree of damage to the natural environment,education costs,loan opportunities,the proportion of agricultural income to annual household income,and the presence of sick people in the household have significant positive effects on the livelihood vulnerability index(LVI)of rural households;while help from relatives and friends,net income per capita,household size,household education,agricultural land area,participation in industrial organizations,number of livestock,purchase of commercial houses,drinking water source,and self-supply of food have significant negative effects.Based on the findings,we believe that local rural households operate in a complex livelihood system and recommend continuous interventions targeting key influences to provide empirical research support for areas facing similar situations.

关键词： Livelihood Vulnerability Rural households Ethnic areas

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Genomic analysis provides insights into the westward expansion of domesticated peaches in china

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Horticultural Plant Journal 2024年第2期10卷 367-375页

作者： Wenqing Li Yong Li Xinwei Wang Guoqing Zhao Gengrui Zhu Ke Cao Weichao Fang Jinlong Wu Kai Ma Changwen Chen Lirong Wang Zhengzhou Fruit Research institute CAASZhengzhouHennan 450009China Xinjiang Academy of Agricultural Sciences UrumqiXinjiang 830091China western Research institute CAASChangjiXinjiang 831100China

Peach, an economically important model plant of the Rosaceae family, has been domesticated and cultivated in china for approximately5 000 years. The Hexi Corridor, an important corridor connecting east-central china and the Tarim Basin, is the starting point of the Silk Road that links china and the Eurasian region. As a globally distributed fruit tree, the spread of peach was accomplished through historical trade routes in the Hexi Corridor and the Tarim Basin. However, knowledge of peach genetic diversity in these regions remains limited. In this study,we examined the relationships and the spread history of domesticated peaches through sequencing and genomic analysis of 161 peach accessions collected from Northwest china, including 43 from the Hexi Corridor and 104 from the Tarim Basin. The results indicate that peach landraces in the Hexi Corridor and the Tarim Basin are derivatives of peaches from the east and south of china (ESC). Notably, the genetic diversity of accessions from both the Hexi Corridor and the Tarim Basin was lower than that of ESC accessions. Reduction of diversity (ROD) and linkage disequilibrium (LD) analyses detected a genetic bottleneck in peaches from these regions. Additionally, these peaches have undergone varying degrees of selection from natural environment. Moreover, genes responsive to biotic and abiotic stresses were under selection, which could be the result of the climate change of Northwest china after the Last Glacial Maximum (LGM). Our findings provide a better understanding of the genetic basis of peach migration in Northwest china. Furthermore, this study expands the available genomic data for peaches and provides critical information for future peach breeding programs.

关键词： Peach Hexi corridor Tarim Basin Genetic diversity Gene flow

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A multifunctional flexible sensor based on PI-MXene/SrTiO_(3) hybrid aerogel for tactile perception

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The Innovation 2024年第3期5卷 44-54页

作者： Shihao Deng Yue Li Shengzhao Li Shen Yuan Hao Zhu Ju Bai Jingyi Xu Lu Peng Tie Li Ting Zhang Nano Science and Technology institute University of Science and Technology of China(USTC)Suzhou 215123China i-lab Nano-X Vacuum Interconnected WorkstationKey Laboratory of Multifunctional Nanomaterials and Smart SystemsSuzhou Institute of Nano-Tech and Nano-Bionics(SINANO)Chinese Academy of Sciences(CAS)Suzhou 215123China School of Nano-Tech and Nano-Bionics University of Science and Technology of China(USTC)Hefei 230026China Jiangxi institute of Nanotechnology 278 Luozhu RoadXiaolan Economic and Technological Development ZoneNanchang 330200China

The inadequacy of tactile perception systems in humanoid robotic manipulators limits the breadth of available robotic applications.Here,we designed a multifunctional flexible tactile sensor for robotic fingers that provides capabilities similar to those of human skin sensing modalities.This sensor utilizes a novel PI-MXene/SrTiO_(3) hybrid aerogel developed as a sensing unit with the additional abilities of electromagnetic transmission and thermal insulation to adapt to certain complex environments.Moreover,polyimide(PI)provides a high-strength skeleton,MXene realizes a pressure-sensing function,and MXene/SrTiO_(3) achieves both thermoelectric and infrared radiation response behaviors.Furthermore,via the pressure response mechanism and unsteady-state heat transfer,these aerogel-derived flexible sensors realize multimodal sensing and recognition capabilities with minimal cross-coupling.They can differentiate among 13 types of hardness and four types of material from objects with accuracies of 94%and 85%,respectively,using a decision tree algorithm.In addition,based on the infrared radiation-sensing function,a sensory array was assembled,and different shapes of objects were successfully recognized.These findings demonstrate that this PI-MXene/SrTiO_(3) aerogel provides a new concept for expanding the multifunctionality of flexible sensors such that the manipulator can more closely reach the tactile level of the human hand.This advancement reduces the difficulty of integrating humanoid robots and provides a new breadth of application scenarios for their possibility.

关键词： utilize integrating insulation

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Spatiotemporal variations,influencing factors,and configurational promotion paths of energy efficiency in china’s cities

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Chinese Journal of Population,Resources and Environment 2024年第1期22卷 74-86页

作者： Ruyu Xu Keliang Wang Zhuang Miao Lingxuan Sun School of economics Ocean University of ChinaQingdao 266011China china western economic Research Center Southwestern University of Finance and EconomicsChengdu 611130China School of economics and Management Southwest Petroleum UniversityChengdu 610500China

The promotion of energy efficiency(EE)helps address energy constraints and promote environmental sustainability.This study comprehensively explores the spatiotemporal variations,influencing factors,and configuration promotion paths of EE in 284 Chinese cities during 2003‒2019 using the global super-efficiency minimum distance to strong efficient frontier(G-S-MinDS),exploratory spatial data analysis(ESDA),multiscale geographically weighted regression(MGWR),and fuzzy set qualitative comparative analysis(fsQCA)methods.The findings are:①china’s cities have an annual average EE of 0.658 with a growth rate of 0.53%,showing considerable promotion potential.②Industrial structure optimization,population agglomeration,economic development,and increased green coverage contribute positively,while government intervention and openness hinder china’s urban EE.③Four configurational promotion paths for enhancing china’s urban EE are identified,where among those paths population density is a core condition,while government intervention is not.This study provides valuable insights into substantially improving urban EE,emphasizing the need for targeted policies to address energy and environmental crises in china.

关键词： Energy efficiency Spatiotemporal variations Influencing factors Configurational promotion paths

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