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为何生育支持政策要以支持家庭为中心?——基于对大众生育观的主题分析

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中国青年研究 2024年第6期 60-67页

作者：马雪杨王增文武汉大学政治与公共管理学院

从单纯地放松生育数量限制到党的二十大报告明确提出要建立生育支持政策体系,能否打破低生育困境?生育的私人和家务属性使生育政策的有效性取决于大众生育观和大众认同性。大众生育观的内核是什么?生育支持政策应如何与之形成积极共生?... 详细信息

从单纯地放松生育数量限制到党的二十大报告明确提出要建立生育支持政策体系,能否打破低生育困境?生育的私人和家务属性使生育政策的有效性取决于大众生育观和大众认同性。大众生育观的内核是什么?生育支持政策应如何与之形成积极共生?文章以2020—2023年所获113份定性证据为基础,阐述大众生育观的内核是围绕家庭完整、家庭责任和家庭成员的全面发展展开的,现代生育制度的核心仍是家庭制度。因此,生育支持政策应以支持家庭建立和维持的全周期为中心,释放生育潜力、激发生育动力。

关键词：生育观家庭中心积极共生生育政策

拉萨河流域土地利用与生态系统服务价值时空演变及驱动因素

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干旱区研究 2024年第6期41卷 1021-1031页

作者：周建伟罗君马雪洋西藏大学生态环境学院西藏拉萨850000 西华师范大学地理科学学院四川南充637009 四川省干旱河谷土壤侵蚀监测与控制工程实验室四川南充637009 大小凉山干旱河谷土壤侵蚀与生态修复野外科学观测研究站四川喜德616753 西华师范大学环境科学与工程学院四川南充637009

土地利用变化对生态文明建设产生强烈影响,进而威胁经济社会与生态环境的可持续发展。基于高精度土地利用数据,分析了拉萨河流域2000—2020年土地利用和生态系统服务价值(Ecosystem Service Value,ESV)时空演变特征,并借助PLUS模型和地... 详细信息

土地利用变化对生态文明建设产生强烈影响,进而威胁经济社会与生态环境的可持续发展。基于高精度土地利用数据,分析了拉萨河流域2000—2020年土地利用和生态系统服务价值(Ecosystem Service Value,ESV)时空演变特征,并借助PLUS模型和地理探测器分别探索了土地利用变化和ESV空间分异的驱动因素。结果表明:(1)2000—2020年拉萨河流域土地利用以草地为主,占流域总面积的85.23%。土地利用呈草地缩减,其余地类扩张的趋势。其中,草地减少2.45%,建设用地、水域和林地分别扩张199.72%、44.64%和21.97%。(2)流域土地利用变化受海拔、年均地温、距湖泊和水库距离等因素影响,其中,海拔对耕地、林地、水域和建设用地扩张的贡献度分别高达0.18、0.11、0.28和0.13,坡度和年均地温对草地和未利用地变化的贡献度分别为0.14和0.15。(3)2000—2020年流域ESV总体增加1.14%(14.96×108元),草地和气候调节分别为ESV贡献最突出的土地利用类型和生态系统服务类型,两者的贡献率分别为87.13%和25.50%。(4)流域ESV具有显著空间分异性,受NDVI、海拔、年均风速和年均气温等因子影响。其中,NDVI的解释力高达0.46,任意两两因子的交互均会增强ESV的分异性。研究结果可为拉萨河流域及类似区域国土空间规划和生态文明建设提供科学参考。

关键词：土地利用生态系统服务价值驱动因子拉萨河流域

全球变暖对青藏高原不同补给类型湖泊生产力的影响

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地理科学 2024年第2期44卷 351-358页

作者：张玉枝马雪洋李倩任娇山西财经大学资源环境学院山西太原030006 兰州大学资源环境学院/西部环境教育部重点实验室甘肃兰州730000 西华师范大学环境科学与工程学院四川南充637009 山西财经大学资源型经济转型发展研究院山西太原030006

研究以青藏高原阿翁错和托素湖湖泊沉积物为研究对象,通过多指标(总有机碳含量、有机碳同位素和有机碳埋藏速率等)综合分析,重建不同补给类型湖泊的生产力变化及碳循环过程。结果显示:全球变暖对不同类型湖泊的生产力的影响存在显著差... 详细信息

研究以青藏高原阿翁错和托素湖湖泊沉积物为研究对象,通过多指标(总有机碳含量、有机碳同位素和有机碳埋藏速率等)综合分析,重建不同补给类型湖泊的生产力变化及碳循环过程。结果显示:全球变暖对不同类型湖泊的生产力的影响存在显著差异。在以降水和冰川融水为主要补给源的阿翁错,全球变暖造成冰川融水补给增加。当指示冰川融水补给量变化的δ^(18)O_(carb)值逐渐偏负时,湖泊沉积物TOC含量逐渐升高;指示冰川融水输入造成湖泊面积持续扩张,营养物质增加,湖泊生产力提高;当湖泊面积扩张较快,即冰川融水在短时间内快速输入时,TOC含量下降,可能是由于当冰川融水输入过多,造成湖水温度下降过快时,底栖藻类生产力下降,进而湖泊固碳能力下降。对于受人类活动影响的托素湖,全球变暖对湖泊水文过程及生产力的影响较小,δ^(18)O_(carb)值变化主要受控于农业灌溉活动引起的湖泊补给水量的变化。当δ^(18)O_(carb)值升高时,TOC含量增加;推测是由于农业灌溉耗水量增加导致湖泊补给水量减少,湖泊水位下降,湖泊底部接收到更多光照,湖泊生产力上升,固碳能力随之上升。

关键词：青藏高原湖泊气候变化湖泊生产力有机碳埋藏速率

Dihydrofolate reductase-like protein inactivates hemiaminal pharmacophore for self-resistance in safracin biosynthesis

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Acta Pharmaceutica Sinica B 2023年第3期13卷 1318-1325页

作者： Ning Shao xueyang ma Ying-Ying Zhang Donghui Yang Ming ma 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 SciencesShanghai 200032China State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China School of Chemistry and materials Science Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China

Dihydrofolate reductase(DHFR),a housekeeping enzyme in primary metabolism,has been extensively studied as a model of acid-base catalysis and a clinic drug ***,we investigated the enzymology of a DHFR-like protein SacH in safracin(SAC)biosynthesis,which reductively inactivates hemiaminal pharmacophore-containing biosynthetic intermediates and antibiotics for ***,based on the crystal structure of SacH−NADPH−SAC-A ternary complexes and mutagenesis,we proposed a catalytic mechanism that is distinct from the previously characterized short-chain dehydrogenases/reductases-mediated inactivation of hemiaminal *** findings expand the functions of DHFR family proteins,reveal that the common reaction can be catalyzed by distinct family of enzymes,and imply the possibility for the discovery of novel antibiotics with hemiaminal pharmacophore.

关键词： Catalytic mechanism Crystal structure Dihydrofolate reductase(DHFR) Hemiaminal pharmacophoreSacH Safracin biosynthesis Self-resistance Tetrahydroisoquinoline(THIQ)alkaloids

Functional Characterization and Crystal Structure of the Type Ei Peptidyl Carrier Protein ColAia in Collismydns Biosynthesis

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Chinese Journal of Chemistry 2020年第9期38卷 963-969页

作者： xueyang ma Guiyang Wang Tan Liu Changbiao Chi Zhongyi Zhang Donghui Yang Wen Liu Ming ma State Key Laboratory of Natural and Biomimetic Drugs Department of Natural MedicinesSchool of Pharmaceutical SciencesPeking University38 Xueyuan RoadHaidian DistrictBeijing 100191China State Key Laboratory of Bioorganic and Natural Products Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of Sciences345 Lingling RoadShanghai 200032China

Summary of main observation and conclusion Collismycins(COLs)are antibiotics characterized by a 2,2'-bipyridine(2,2'-BP)core composed of a trisubstituted ring A and an unmodified ring *** 2,2'-BP core,which possesses metal-chelating ability and plays key roles in various biological activities of COLs,is biosynthesized by a nonribosomal peptide synthetase(NRPS)-polyketide synthase(PKS)hybrid *** starter module of the NRPS-PKS hybrid machinery consists of a type II peptidyl carrier protein(PCP)ColA1a and an adenylation protein *** here report the functional characterization of ColAia and ColAlb in vitro,confirming their functions in selection and loading of picolinic acid(PA),instead of normal amino acid substrates,as the origin of ring B in *** 2.1 A crystal structure of ColAia was solved,revealing structural features including the additional helices ala,alb and missing helix a3,which may reflect unique interactions of ColAia with other NRPS-PKS proteins/domains or *** and tertiary structural comparison of ColAia with other PCPs revealed the structural basis for their typical a-helical bundle,providing a better understanding of the structural flexibility of *** results facilitate the starter module engineering for the generation of COL derivatives with ring B modifications in the future.

关键词： conclusion machinery fir

纳米气泡水与沼液联合浸泡对水稻秸秆厌氧产气性能的影响

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可再生能源 2024年第5期42卷 587-591页

作者：邢帆王恩振吴兴国李玉蓉马雪杨王晓徐吉磊董仁杰郭建斌青岛汇君环境能源工程有限公司山东青岛266100 中国农业大学工学院北京100083

文章以水稻秸秆为研究对象,采用4种浸泡溶剂(去离子水、纳米气泡水、沼液、纳米气泡水联合沼液)对水稻秸秆进行5 d厌氧预处理,研究了不同浸泡预处理对挥发性脂肪酸含量、木质纤维素含量以及甲烷产率的影响。结果表明:纳米气泡水和沼液... 详细信息

文章以水稻秸秆为研究对象,采用4种浸泡溶剂(去离子水、纳米气泡水、沼液、纳米气泡水联合沼液)对水稻秸秆进行5 d厌氧预处理,研究了不同浸泡预处理对挥发性脂肪酸含量、木质纤维素含量以及甲烷产率的影响。结果表明:纳米气泡水和沼液浸泡均促进了水稻秸秆的水解过程;纳米气泡水联合沼液组的处理效果最为突出,挥发性脂肪酸含量达到了6470 mg/L,纤维素和半纤维素降解率分别达到了12.1%和23.7%,最大累积甲烷产率提高了19.5%。

关键词：水稻秸秆厌氧消化纳米气泡水浸泡预处理

Re-delocalization of localized d-electrons in VO_(2)(R)-VS_(4)hetero-structure enables high performance of rechargeable Mg-ion batteries

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Journal of magnesium and Alloys 2024年第5期12卷 1830-1840页

作者： Lijiao Zhou Chao Shen xueyang Hou Zhao Fang Ting Jin Keyu Xie School of materials Science and Engineering Northwestern Polytechnical UniversityXi’an 710072China School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China

Rechargeable Mg-ion batteries(MIBs)have attracted much more attentions by virtue of the high capacity from the two electrons ***,the reversible Mg^(2+)diffusion in cathode materials is restricted by the strong interactions between the high-polarized bivalent Mg^(2+)ions and anionic ***,we design and propose a hetero-structural VO_(2)(R)-VS_(4)cathode,in which the re-delocalized d-electrons can effectively shield the polarity of Mg^(2+)***,the electrons should spontaneously transfer from VS_(4)to VO_(2)(R)through the interfaces of hetero-structure due to the lower work function value of VS_(4).Furthermore,the internal electrons transfer lead to the electronic injection into VO_(2)(R)from VS_(4)and the partially broken V-V dimers,indicating the presence of lone pair electrons and charge *** from the shield effect of re-delocalized electrons,and the weakened attraction between cations and O/S anions enables more S^(2-)-S_(2)^(2-)redox groups to participate the electrochemical reactions and compensate the double charge of Mg^(2+)***,VO_(2)(R)-VS_(4)hetero-structure exhibits a high specific capacity of 554 ma h g^(-1)at 50 ma g^(-1).It is believed that the charge re-delocalization of cathode extremely boost the Mg^(2+)ions migration for the high-capacity of MIBs.

关键词： Mg-ion batteries Cathode Charge delocalization Electronic structure Heterostructure

Two glucosylated angucyclines from deep-sea-derived Streptomyces ***-ma01297

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Journal of Chinese Pharmaceutical Sciences 2019年第12期28卷 835-842页

作者： xueyang ma Guiyang Wang Zhongyi Zhang Tongtong Geng Xiaoxu Sun Donghui Yang Xixiang Tang Ming ma State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking University Health Science CenterBeijing 100191China Key Laboratory of marine Genetic Resources Third Institute of OceanographyMinistry of Natural ResourcesXiamen 361005China

Angucyclines are aromatic polyketides produced by typeⅡpolyketide synthase(PKS)exclusively from *** natural products contain hydrolyzable sugar moieties that attach to various positions of the polyketide skeleton and expand the structural *** here report the isolation of two new angucyclines(1 and 2)from the deep-sea-derived Streptomyces ***-ma01297,which was isolated from a sediment sample collected at a depth of 3202 meters from the Indian *** structures of the two new compounds were elucidated based on comprehensive methods,including NMR,MS and CD *** 1 and 2 featured a 1-O-β-D-glucopyranosyl moiety that has not been reported for *** biological activity assays,including antibacterial,cytotoxicity and anti-inflammatory assays,were carried out,and compounds 1 and 2 showed no *** results set the stage for biosynthetic research and more biological activity assays in the future.

关键词： Angucyclines Deep-sea-derived Streptomyces Glucopyranosyl moiety

Synthesis of two substrate mimics of thioesterase in the biosynthesis of cyclic depsipeptide WS9326A

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Journal of Chinese Pharmaceutical Sciences 2019年第9期28卷 605-614页

作者： Zhongyi Zhang Hanxuan Wang Guiyang Wang xueyang ma Tan Liu Tongtong Geng Xiaoxu Sun Donghui Yang Suwei Dong Ming ma State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China

WS9326 A is a tachykinin receptor antagonist and quorum sensing inhibitor discovered from several Streptomyces *** structure of WS9326 A features a(Z)-pentenylcinnamoyl moiety attached on a cyclic depsipeptide skeleton,which is biosynthesized by nonribosomal peptide synthetases(NRPS).The regioselective cyclization in the last step of NRPS catalysis,which is proposed to be catalyzed by a thioesterase(TE)domain in the last module,has not been experimentally *** here report the synthesis of two substrate mimics(1 and 2)of the TE(WS9326 A-TE)in WS9326 A biosynthesis,by using Fmoc-based solid-phase peptide synthesis(SPPS)*** 1 and 2 are new compounds whose structures have been elucidated based on NMR and HRESIMS *** N-terminal cinnamoyl moiety and C-terminal methylated L-Ser moiety in 2 were incorporated under the mild SPPS *** the isolation difficulties of substrate of WS9326 A-TE from the Streptomyces producers of WS9326 A,our synthesis of 1 and 2 set the stage for the reconstitution of WS9326 A-TE’s catalytic reaction in vitro in the future.

关键词： Solid-phase peptide synthesis Thioesterase WS9326A