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Chain Dynamics Heterogeneity in Plasticized Poly(vinyl butyral)(PVB) as Elucidated by Solid-State NMR

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Chinese Journal of Polymer Science 2024年第1期42卷 113-124,I0010页

作者： Jing Lv Xu Chen zi-Shuo Wu Ya-Hui Li Wei Chen National Synchrotron Radiation Laboratory Anhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmCAS Key Laboratory of Soft Matter ChemistryUniversity of Scienceand Technology of ChinaHefei 230026China

The chain dynamics heterogeneity of the poly(vinyl butyral)(PVB) plasticized by triethylene glycol bis(2-ethylhexa noate)(TEG-EH) was investigated by various solid-state NMR *** plasticized PVB shows two domains in distinct molecular dynamics differences,namely,rigid and soft domains,where the latter is the plasticizer-rich *** time domain low field NMR was first used to investigate the dynamics heterogeneity of the plasticized PVB,and the results show the decreasing activated energy of components in the soft domain of plasticized PVB(E_a=20.2 kJ/mol) as compared with that of the pristine one(E_a=24.3 kJ/mol).Detailed dynamics heterogeneity was obtained by high-field NMR with site-specific *** quadrupole-echo ~2H-NMR was adopted to elucidate the dynamics heterogeneity of the vinyl alcohol(VA) units,where only the hydroxyl group of VA is *** ~1H-^(13)C WISE NMR spectra show that there is not much difference in the mobility of the VB unit in PVB with and without plasticizer,whereas the glass transition temperature differed by approximately 53℃.This is further supported by Torchia's T_1 relaxation *** origin of such an unusual phenomenon is attributed to the critical role of the remaining VA(~22%) in the soft domain,where the VA units locally aggregate through hydrogen ***,the existence of a mobility gradient in the VB unit has been ***,the mobility difference for VB with different stereo-geometry(meso or racemic conformation) is observed for the first *** indicates the importance of modulating the ratio of meso over racemic VB for controlling the macroscopic perfo rmance of PVB.

关键词： Poly(vinyl butyral) Dynamics heterogeneity Plasticizer Solid state NMR

Use of Evidence-Based Research Approach in RCTs of Acupuncture-Related Therapies for Primary Dysmenorrhea: A Meta-Research

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Chinese Journal of Integrative Medicine 2024年第6期30卷 551-558页

作者： HU Xiao-yi TIAN zi-yu CHEN Huan HU Xiang-yu MING Tian-yu PENG Hao-xuan JIAO Rui-min SHI lan-jun XIU Wen-cui YANG Ji-wei GANG Wei-juan JING Xiang-hong Institute of Acupuncture and Moxibustion China Academy of Chinese Medical SciencesBeijingChina Department of Traditional Chinese Medicine Beijing Puren HospitalBeijing100062China

Objective To assess the use of evidence-based research(EBR)approach in randomized controlled trials(RCTs)of acupuncture-related therapies for primary dysmenorrhea(PD).Methods PubMed,EMBASE,Cochrane Library,China National Knowledge Infrastructure,Wanfang Database,Chinese Biomedical Database,and China Science and Technology Journal Database were searched from January 2013 to December 2022 for RCTs of acupuncture on *** full text and references of each RCT were read to assess whether systematic reviews(SRs)or other types of studies with similar research questions and end-users’perspectives were cited to justify and design the *** addition,the discussion section were analyzed to evaluate whether trials placed the new result in the existing SRs to draw a *** logistic regression was used to find variables that associated with 3 aspects of EBR approach:(1)citing clinical studies for justification,(2)citing relevant studies that obtain the perspectives of end users,and(3)citing clinical studies for results *** Of 473 RCTs included,45.67%(216)of the trials cited relevant similar studies,21.56%(102)referenced to the studies that collected end-users’perspectives,and 10.99%(52)placed result in the context of the previous *** RCTs appropriately applied EBR *** all the included studies,3.17%(15)of the trials used SRs to inform study questions but none of them used updated SRs with acceptable quality;1.05%(5)of the trials cited SRs of end-user’s perspectives in the justification and design of the study,and only 1 trial added results in existing SR to draw a *** of publication,language,funding,registration,ethical approval and number of sites were significantly associated with 1 of the 3 aspects of EBR *** Few RCTs in acupuncture-related therapies for PD used the EBR approach to minimize research ***,research institutes,funding agencies,ethics committees,journals and peer

关键词： evidence-based research acupuncture therapy primary dysmenorrhea randomized controlled trial systematic review end-usersperspective meta-research

Regulatory factors of Nrf2 in age-related macular degeneration pathogenesis

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1344-1362页

作者： zi-Ling Hu Yu-Xuan Wang zi-Yue Lin Wen-Shuo Ren Bo Liu Hui Zhao Qiong Qin Five Year Program of Ophthalmology and Optometry 2019 Beijing Tong Ren HospitalCapital Medical UniversityBeijing 100054China Four Year Program of Traditional Chinese Pharmacy 2020 School of Traditional Chinese MedicineCapital Medical UniversityBeijing 100069China School of Traditional Chinese Medicine Capital Medical UniversityBeijing 100069China Beijing Key Laboratory of TCM Collateral Disease Theory Research Beijing 100069China Five Year Program of Ophthalmology and Optometry 2021 School of Basic Medical SciencesCapital Medical UniversityBeijing 100069China Biochemistry&Molecular Biology School of Basic Medical SciencesCapital Medical UniversityBeijing 100069China

Age-related macular degeneration(AMD)is a complicated disease that causes irreversible visual *** evidences pointed retinal pigment epithelia(RPE)cells as the decisive cell involved in the progress of AMD,and the function of anti-oxidant capacity of PRE plays a fundamental physiological *** factor erythroid 2 related factor 2(Nrf2)is a significant transcription factor in the cellular anti-oxidant system as it regulates the expression of multiple anti-oxidative *** functions of protecting RPE cells against oxidative stress(OS)and ensuing physiological changes,including inflammation,mitochondrial damage and autophagy dysregulation,have already been *** the roles of upstream regulators of Nrf2 could provide further insight to the OS-mediated AMD *** the first time,this review summarized the reported upstream regulators of Nrf2 in AMD pathogenesis,including proteins and miRNAs,and their underlying molecular mechanisms,which may help to find potential targets via regulating the Nrf2 pathway in the future research and further discuss the existing Nrf2 regulators proved to be beneficial in preventing AMD.

关键词： Nrf2 upstream regulators retinal pigment epithelia age-related macular degeneration oxidative stress

Enantioselective Alkylation of Aldehydes with Organoborons Enabled by Nickel/N-Heterocyclic Carbene Catalysis

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Chinese Journal of Chemistry 2024年第18期42卷 2161-2165页

作者： Song-Yang Liu zi-Chao Wang Shi-Liang Shi College of Chemistry and Material Science Shanghai Normal University100 Guilin RoadShanghai 200234China State Key Laboratory of Organometallic Chemistry Shanghai Institute of rganic ChemitryUniversity of Chinee Academy of Scienc Chinese Academy of Sciences345 Lingling RoadShanghai 200032China

Transition-metal-catalyzed asymmetric alkylation of aldehydes represents a straightforward strategy for the synthesis of chiral secondary ***,efficient methods using organoborons as coupling reagents are ***,we report a highly enantioselective nickel-catalyzed alkylation reaction of aldehydes,using readily available alkylborons as nucleophiles.A wide variety of chiral secondary alcohols were prepared from commercially available aldehydes with high *** key to the excellent enantioselectivity and chemoselectivity was the employment of a bulky C2-symmetric chiral NHC *** protocol features excellent enantiocontrol,mild conditions,and good functional group compatibility.

关键词： Enantioselective alkylation Nickel catalysis N-Heterocyclic carbene Organoborons Chiral alcohols Asymmetric catalysis C-C coupling Synthetic methods

Microplastic exposure disturbs sleep structure,reduces lifespan,and decreases ovary size in Drosophila melanogaster

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Zoological Research 2024年第4期45卷 805-820页

作者： Wei Yan zi-Jie Li zi-Yi Lin Shu-Qin Ji William Ka Fai Tse Zhi-Qiang Meng Chang Liu Lei Li Shenzhen-Hong Kong Institute of Brain Science Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong 518000China CAS Key Laboratory of Brain Connectome and Manipulation the Brain Cognition and Brain Disease InstituteShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong 518000China Laboratory of Developmental Disorders and Toxicology Center for Promotion of International Education and ResearchFaculty of AgricultureKyushu UniversityFukuokaFukuoka 819-0395Japan Shenzhen Key Laboratory of Drug Addiction the Brain Cognition and Brain Disease InstituteShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong 518000China Guangdong Provincial Key Laboratory of Brain Connectome and Behavior Brain Cognition and Brain Disease InstituteShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong 518000China

The organ-specific toxicity resulting from microplastic(MP)exposure has been extensively explored,particularly concerning the gut,liver,testis,and ***,under natural conditions,these effects are not restricted to specific organs or *** whether MP exposure presents a systemic threat to an entire organism,impacting factors such as lifespan,sleep,and fecundity,is *** this study,we investigated the effects of dietary exposure to two different doses of MPs(1–5μm)using the terrestrial model organism Drosophila *** indicated that the particles caused gut damage and remained within the digestive *** MP exposure significantly shortened the lifespan of adult *** short-term exposure disrupted sleep patterns,increasing the length of daytime sleep ***,one week of MP exposure reduced ovary size,with a trend towards decreased egg-laying in mated *** MPs did not penetrate the brain or ovaries,transcriptome analysis revealed altered gene expression in these *** the ovary,Gene Ontology(GO)analysis indicated genotoxic effects impacting inflammation,circadian regulation,and metabolic processes,with significant impacts on extracellular structure-related *** the brain,GO analysis identified changes in pathways associated with proteolysis and carbohydrate ***,this study provides compelling evidence of the systemic negative effects of MP exposure,highlighting the urgent need to address and mitigate environmental MP pollution.

关键词： Microplastics Sleep Lifespan Reproduction Risk assessment Drosophila melanogaster

Applying dynamic light scattering to investigate the self-assembly process of DNA nanostructures

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Chinese Chemical Letters 2024年第3期35卷 316-320页

作者： Wei Yuan Gui-Zhi Dong Hui Ning Xiang-Xiang Guan Jia-feng Cheng zi-Wei Shi Xiu-Ji Du Si-Wen Meng Dong-Sheng Liu Yuan-Chen Dong CAS Key Laboratory of Colloid Interface and Chemical ThermodynamicsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Dandong Bettersize Instruments Ltd. Dandong 118000China Key Laboratory of Organic Optoelectronics&Molecular Engineering of the Ministry of Education Department of ChemistryTsinghua UniversityBeijing 100084China Department of Chemistry Renmin University of ChinaBeijing 100872China

Understanding the dynamic assembly process of DNA nanostructures is important for developing novel strategy to design and construct functional *** this work,temperature-controlled dynamic light scattering(DLS)strategy has been applied to study the global assembly process of DNA origami and DNA *** the temperature dependent size and intensity profiles,the self-assembly process of various DNA nanostructures with different morphologies have been well-studied and the temperature transition ranges could be *** advantage of the DLS information,rapid preparation of the DNA origami and the brick assembly has been realized through a constant temperature *** results demonstrate that the DLS-based strategy provides a convenient and robust tool to study the dynamic process of forming hieratical DNA structures,which will benefit understanding the mechanism of self-assembly of DNA nanostructures.

关键词： Dynamic light scattering Self-assembly process DNA nanostructures Temperature transition ranges Rapid preparation

Sequence structure controllable polymerization-induced self-assembly

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Science China Chemistry 2024年第1期67卷 390-397页

作者： zi-Xuan Chang Ren-Man Zhu Chun-Yan Hong Wen-Jian Zhang Department of Polymer Science and Engineering University of Science and Technology of ChinaHefei 230026China Institute of Physical Science and Information Technology Anhui UniversityHefei 230601China Key Laboratory of Environment-Friendly Polymeric Materials of Anhui Province Anhui UniversityHefei 230601China

Polymerization-induced self-assembly(PISA)combines synthesis and self-assembly of artificial polymers in one-pot,which brings us one step closer to emulating ***,the reported PISA formulations primarily focus on developing nano-objects with new chemical compositions and rarely on structural regulation of polymers with specific ***,sequence structure controllable polymerization-induced self-assembly(SCPISA)is reported by using 7-(2-methacryloyloxyethoxy)-4-methylcoumarin(CMA)as a *** the copolymerization of 2-hydroxyethyl methacrylate(HEMA)and CMA,controlled incorporation of CMA units into the polymer chains can be realized by programmable light/heat ***-based P(HEMA-co-CMA)copolymers with the same composition but different sequence structures generate a range of ***,the morphologies of the resultant nano-objects can also be controlled by regulating the feed molar ratio of CMA and HEMA,which is similar to the conventional PISA,but the synthesis procedure is obviously simplified in *** versatility of the methodology is further demonstrated by the fabrication of different functional nano-objects with sequence structure-dependent morphologies in SCPISA systems with different functional monomers.

关键词： polymerization-induced self-assembly sequence-controlled polymers PET-RAFT polymerization

Photocaged activity-based probes for improved monitoring of protein S-sulfenylation in living cells

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Chinese Chemical Letters 2024年第2期35卷 451-454页

作者： Jiahao Zhang Haiyue Peng zi'an Chen Guorui Li Jing Huang State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan Provincial Key Laboratory of Animal Models and Molecular MedicineSchool of Biomedical SciencesHunan UniversityChangsha 410082China

Protein S-sulfenylation(protein sulfenic acid),as one of the most significant oxidative post-translational modifications(OxiPTMs),plays a vital role in regulating protein function.A variety of activity-based probes have been developed to profile sulfenic acid in living ***,due to the transient presence and low content of sulfenic acid in living cell,high doses of probes are needed to achieve efficient *** importantly,current probes have no temporal control over sulfenic acid *** overcome these limitations,two caged cysteine sulfenic acid probes DYn-2-ONB and DYn-2-Cou with either an o-nitrobenzyl or coumarin protecting group were developed in this *** probes can be efficiently uncaged via irradiation to produce the active C-nucleophile probe *** assay in living cells demonstrated DYn-2-ONB exhibited better labeling capacity compared with DYn-2,providing it as a powerful tool for improved monitoring of protein S-sulfenylation in living cells.

关键词： Cysteine Sulfenic acid Activity-based probe Photocage Light activation Protein S-sulfenylation

Pre-existing orthorhombic embryos-induced hexagonal-orthorhombic martensitic transformation in MnNiSi_(1-x)(CoNiGe)_x alloy

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Chinese Physics B 2024年第4期33卷 691-699页

作者：张婷婷龚元元鲁子骞徐锋 MIIT Key Laboratory of Advanced Metallic and Intermetallic Materials Technology School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing 210094China

The thermal-elastic martensitic transformation from high-temperature Ni_(2)In-type hexagonal structure to low-temperature TiNiSi-type orthorhombic structure has been widely studied in MnMX(M=Ni or Co,and X=Ge or Si)***,the answer to how the orthorhombic martensite nucleates and grows within the hexagonal parent is still *** this work,the hexagonal-orthorhombic martensitic transformation in a Co and Ge co-substituted MnNiSi is *** can find some orthorhombic laths embedded in the hexagonal parent at a temperature above the martensitic transformation start temperature(M_(s)).With the the sample cooing to M_(s),the laths turn broader,indicating that the martensitic transformation starts from these pre-existing orthorhombic *** observation suggests that these pre-existing orthorhombic laths do not originate from the hexagonal-orthorhombic martensitic transformation because of the difference between atomic occupations of doping elements in the hexagonal parent and those in the preexisting orthorhombic *** phenomenological crystallographic theory and experimental investigations prove that the pre-existing orthorhombic lath and generated orthorhombic martensite have the same crystallography relationship to the hexagonal ***,the orthorhombic martensite can take these pre-existing laths as embryos and grow *** work implies that the martensitic transformation in MnNiSi_(1-x)(CoNiGe)_(x) alloy is initiated by orthorhombic embryos.

关键词： martensitic transformation MnMX alloy orthorhombic embryo crystallography relationship