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Reoxidation of Transition-metal Catalysts with O2

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Chinese Journal of Chemistry 2017年第9期35卷 1349-1365页

作者： Xinyao Li ning jiao State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Xue Yuan Rd. 38 Beijing 100191 China State Key Laboratory of Organometallic Chemistry Chinese Academy of Sciences Shanghai 200032 China

Transition-metal catalyzed oxidation reactions are central components of organic chemistry. On behalf of green and sustainable chemistry, molecular oxygen （02） has been considered as an ideal oxidant due to its natu... 详细信息

关键词： transition-metal catalysts molecular oxygen aerobic oxidation oxygenation dehydrogenative coupling

The low-latitude sodium layer:comparative data from lidar observations at hainan,China and São Paulo,Brazil

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Earth and Planetary Physics 2025年第1期9卷 39-53页

作者： Fang Wu Jing jiao GuoTao Yang LiFang Du ZhengKuan Liu HaoRan Zheng JiXin Guo ShaoHua Gong YaJun Zhu State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China hainan National Field Science Observation and Research Observatory for Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China China-Brazil Joint Laboratory for Space Weather NSSC/INPESão Josédos Campos 12227-010Brazil School of Physics and Electronics Engineering Hainan Normal UniversityHaikou 571158China

Physical and chemical processes observed in the mesosphere and thermosphere above the Earth’s low latitudes are complex and highly interrelated to activity in the low-latitude *** sodium detected by lidar can yield clues to dynamic and chemical processes in these spatial layers above the Earth’s *** paper is based on sodium layer data collected at two low-latitude stations,one in the northern hemisphere and one in the *** low-latitude sodium layer exhibits conspicuous seasonal variations in shape,density,and altitude;these variations are similar between Earth’s hemispheres:sodium layer density at both stations reaches its seasonal maximum in autumn and minimum in ***,maximal Na density over Brazil is greater than that over *** variations of Na density above the two low-latitude stations are also similar;at both,maxima are observed before *** variations of the Na layer over Brazil that differ from those observed in the northern hemisphere may be related to the South Atlantic Magnetic Anomaly(SAMA)or fountain *** suggest that low-latitude Na layer data may provide useful additional evidence that could significantly improve the low-latitude part of the WACCM-Na model.

关键词： metallic sodium layer seasonal variation nocturnal variation lidar

Peripheral mitochondrial DNA as a neuroinflammatory biomarker for major depressive disorder

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Neural Regeneration Research 2025年第6期20卷 1541-1554页

作者： Jinmei Ye Cong Duan Jiaxin Han Jinrong Chen ning Sun Yuan Li Tifei Yuan Daihui Peng Division of Mood Disorder Shanghai Mental Health CenterShanghai Jiao Tong University School of MedicineShanghaiChina Department of Psychiatry First Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Shanghai Key Laboratory of Psychotic Disorders Brain Health InstituteNational Center for Mental DisordersShanghai Mental Health CenterShanghai Jiao Tong University School of MedicineShanghaiChina Co-Innovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina

In the pathogenesis of major depressive disorder, chronic stress-related neuroinflammation hinders favorable prognosis and antidepressant response. Mitochondrial DNA may be an inflammatory trigger, after its release from stress-induced dysfunctional central nervous system mitochondria into peripheral circulation. This evidence supports the potential use of peripheral mitochondrial DNA as a neuroinflammatory biomarker for the diagnosis and treatment of major depressive disorder. Herein, we critically review the neuroinflammation theory in major depressive disorder, providing compelling evidence that mitochondrial DNA release acts as a critical biological substrate, and that it constitutes the neuroinflammatory disease pathway. After its release, mitochondrial DNA can be carried in the exosomes and transported to extracellular spaces in the central nervous system and peripheral circulation. Detectable exosomes render encaged mitochondrial DNA relatively stable. This mitochondrial DNA in peripheral circulation can thus be directly detected in clinical practice. These characteristics illustrate the potential for mitochondrial DNA to serve as an innovative clinical biomarker and molecular treatment target for major depressive disorder. This review also highlights the future potential value of clinical applications combining mitochondrial DNA with a panel of other biomarkers, to improve diagnostic precision in major depressive disorder.

关键词： biomarker cytokine exosomes inflammasome major depressive disorder microglia mitochondrial DNA mitochondrial dysfunction neuroinflammation Toll-like receptor

Organic Synthesis through Radical Innovation:Frustrated Radical Pairs

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Chinese Journal of Chemistry 2024年第10期42卷 1157-1160页

作者： Zhibin Hu Zengrui Cheng ning jiao State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China Shanghai Key Laboratory of Green Chemistry and Chemical Processes East China Normal UniversityShanghai 200062China

Frustrated Lewis Pairs(FLPs)represent a unique class of interactions in Lewis acid-base chemistry,driven by spatial hindrance or incongruent orbital energy levels that hinder the formation of effective coordination *** have received significant attention for their application in activating small molecules and facilitating organic synthesis *** developments have led to the emergence of Frustrated Radical Pairs(FRPs)as an extension of the radical *** are formed from FLPs through Single Electron Transfer(SET)and exhibit the ability to activate a variety of chemical *** research on FLPs is well-established,investigations into FRPs in organic reactions remain *** review highlights the current state of FRPs in organic synthesis,delves into mechanistic insights,explores their potential,and underscores the challenges in this emerging field.

关键词： Radicals Frustrated Lewis Pairs Frustrated Radical Pairs Methodology and reactions Reaction mechanisms

Maternal helminth infection protects offspring from high-fat-diet-induced obesity through altered microbiota and SCFAs

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Cellular & Molecular Immunology 2023年第4期20卷 389-403页

作者： Chien-Wen Su Chih-Yu Chen Tangyou Mao ning Chen Nicholas Steudel Lefei jiao Jinggang Lan Alessio Fasano WAllan Walker hai ning Shi Mucosal Immunology and Biology Research Center Massachusetts General Hospital and Harvard Medical SchoolCharlestownMAUSA Laboratory for Lipid Medicine and Technology Department of MedicineMassachusetts General Hospital and Harvard Medical SchoolCharlestownMAUSA Department of Gastroenterology Dongfang HospitalBeijing University of Chinese MedicineBeijingChina Shenzhen Institute for Drug Control ShenzhenChina.

Helminth-induced Th2 immunity and gut microbiota have been recently shown to be highly effective in modulating metabolic syndromes in animal *** study aimed to determine whether maternal immunity and microbial factors affect the induction and development of obesity in ***,Heligomosomoides polygyrus(Hp)-infected or control female C57BL/6J mice mated with normal males and their offspring were fed a high-fat diet(HFD)for 9 weeks after *** results showed that Hp-induced maternal outcomes during gestation and lactation significantly impacted offspring metabolic *** was evidenced by results showing that offspring from helminth-infected mothers on an HFD(Hp-offspring+HFD)gained significantly less body weight than those from uninfected mothers(Cont-offspring+HFD).Hp-offspring+HFD exhibited no Th2 phenotype but displayed a pattern of gut microbiota composition similar to that of Hp-infected ***-fostering experiments confirmed that the helminth-induced maternal attenuation of offspring obesity was mediated through both prenatal and postnatal *** results further showed that helminth-infected dams and their offspring had a markedly altered gut microbiome composition,with increased production of short-chain fatty acids(SCFAs).Intriguingly,Hp-infected mothers and Hp-offspring+HFD showed increased SCFA receptor(GPR)expression in adipose and colonic tissues compared to noninfected mothers and Cont-offspring+HFD,***,SCFA supplementation to the pups of uninfected control mothers during lactation protected against HFD-induced weight gain,which corresponded with changes in gut bacterial ***,our findings provide new insights into the complex interaction of maternal immune status and gut microbiome,Hp infection,and the immunity and gut microbiome in obese-prone offspring in infant life.

关键词： Helminth Maternal Th2 immunity Microbiota Offspring Obesity SCFAs

Microstructure and Mechanical Properties of Semi-continuous Equal-channel Angular Extruded Interstitial-free Steel

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Journal of Iron and Steel Research International 2016年第2期23卷 160-165页

作者： Bo YAN Si-hai jiao Dian-hua ZHANG State Key Laboratory of Rolling and Automation Northeastern University Research and Development Center Baoshan Iron and Steel Co.Ltd.

An innovative method called semi-continuous equal channel angular extrusion （SC-ECAE） has been devel- oped to produce ullrafine grained steel by inducing severe plastic deformation. In contrast to the external forces that are exerted on specimens in traditional ECAE, the driving forces are applied on the dies in the novel SC EACE process. Commercial interslitial-free steel sheets with width of 160 mm and tbickness of 2 mm were processed re peatedly to various passes at room temperature using this method. The microstructural evolution was characterized using high-resolution electron backscatter diffraction （EBSD）, and the mechanical properties were investigated by tensile testing. The EBSD images indicated that the fraction of high angle boundaries （HABs） began to increase gradually after four passes; after six passes, elongated HAB structures with nearly submicron-scale average spacings were formed. The tensile testing results showed that strengthening was accompanied by a decrease in tensile ductili- ly, but no significant anisotropy was observed. After 10 passes, a final HAB fraction of about 90% and an overall grain size of 0.55 μm, yield strength of 638.7 MPa, an ultimate tensile strength （UTS） of 710.3 MPa, and a totfd elongation of 12.0 % were obtained.

关键词： severe plastic deformation semi-continuous equal channel angular extrusion IF steel ultrafine grainedstructure EBSD

Roles of chromatin assembly factor 1 in the epigenetic control of chromatin plasticity

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Science China(Life Sciences) 2012年第1期55卷 15-19页

作者： HUANG hai jiao RenJie State Key Laboratory of Brain and Cognitive Sciences Institute of BiophysicsChinese Academy of SciencesBeijing 100101China Graduate University of Chinese Academy of Sciences Beijing 100080China

Genetic information embedded in DNA sequence and the epigenetic information marked by modifications on DNA and his- tones are essential for the life of eukaryotes. Cells have evolved mechanisms of DNA duplication and chromatin restoration to ensure the inheritance of genetic and epigenetic information during cell division and development. In this review, we focus on the maintenance of epigenetic landscape during chromatin dynamics which requires the orchestration of histories and their chaperones. We discuss how epigenetic marks are re-established in the assembly of new chromatin after DNA replication and repair, highlighting the roles of CAF-1 in the process of changing chromatin state. The functions of CAF-1 provide a link be- tween chromatin assembly and epigenetic restoration.

关键词： CAF-1 epigenetic information chromatin plasticity signal transduction histone chaperone

Rh-catalyzed Transient Directing Group Promoted C-H Amidation of Benzaldehydes Utilizing Dioxazolones

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Chinese Journal of Chemistry 2018年第3期36卷 213-216页

作者： Xiaoyang Wang Song Song ning jiao State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Xue Yuan Rd. 38 Beijing 200192 China State Key Laboratory of Organometallic Chemistry Chinese Academy of Sciences Shanghai 200032 China

Transition-metal catalyzed C--H functionalization of benzaldehydes is of great interest in organic synthesis. Herein, we developed a transient directing group assisted amidation of benzaldehydes catalyzed by rhodium catalyst. With the employment of 10 mol% of 4-trifluoromethyl aniline, the in situ generated imine groups as the directing group efficiently enable this transformation. By using this protocol, a wide range of benzaldehydes were efficiently converted into the corresponding N-（2-formylphenyl）benzamides utilizing dioxazolones as the nitrogen source.

关键词： amidation benzaldehydes rhodium C--H functionalization transient directing group

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肠道菌群体外酵解不同种类单糖研究

陕西科技大学学报 2025年第1期43卷 35-45页

作者：郝俊宇孙玉姣高润凝姚佳轩陕西科技大学食品科学与工程学院陕西西安710021 陕西农产品加工技术研究院陕西西安710021

碳水化合物的结构特征影响着其被微生物的利用效果,为了探究其结构对肠道菌群的影响,本文从单糖组成角度入手,研究了以葡萄糖、甘露糖、阿拉伯糖、半乳糖、岩藻糖、木糖、鼠李糖、葡萄糖醛酸和半乳糖醛酸这九种单糖作为碳源,在进行体外... 详细信息

碳水化合物的结构特征影响着其被微生物的利用效果,为了探究其结构对肠道菌群的影响,本文从单糖组成角度入手,研究了以葡萄糖、甘露糖、阿拉伯糖、半乳糖、岩藻糖、木糖、鼠李糖、葡萄糖醛酸和半乳糖醛酸这九种单糖作为碳源,在进行体外培养的过程中,肠道菌群及其代谢产物发生的变化.主要检测了OD_(600)、糖消耗量、短链脂肪酸和乳酸含量等指标.经过筛选后,对七种中性单糖混合发酵的培养基进行了单糖组成分析,明确了七种中性单糖在酵解过程中的被利用顺序.以16S rRNA高通量测序分析了肠道菌群群落多样性和丰度变化,发现不同单糖在被乳酸杆菌等有益菌利用的过程中存在竞争关系,甘露糖和半乳糖有利于肠道中的乳酸杆菌属等有益菌的生长繁殖,研究结果将为多糖与肠道菌群的构效关系研究提供了理论依据.

关键词：单糖组成体外酵解短链脂肪酸肠道菌群多样性分析