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Higher levels of the lipophilic antioxidants coenzyme Q_(10) and vitamin E in long-lived termite queens than in short-lived workers

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Insect Science 2024年第1期31卷 201-210页

作者： Eisuke Tasaki Yorihiro Yamamoto Yoshihito Iuchi Department of Biological Chemistry Graduate School of Sciences and Technology for InnovationYamaguchi UniversityYamaguchiJapan school of bioscience and Biotechnology Tokyo University of TechnologyHachiojiTokyoJapan

Termite queens and kings live longer than nonreproductive *** molecular mechanisms contributing to their long lifespan have been investigated;however,the underlying biochemical explanation remains *** Q(CoQ),a component of the mitochondrial electron transport chain,plays an essential role in the lipophilic antioxidant defense *** beneficial effects on health and longevity have been well studied in several ***,we demonstrated that long-lived termite queens have significantly higher levels of the lipophilic antioxidant CoQ_(10) than *** chromatography analysis revealed that the levels of the reduced form of CoQ_(10) were 4 fold higher in the queen's body than in the worker's *** addition,queens showed 7 fold higher levels of vitamin E,which plays a role in antilipid peroxidation along with CoQ,than ***,the oral administration of CoQ_(10) to termites increased the CoQ_(10) redox state in the body and their survival rate under oxidative *** findings suggest that CoQ_(10) acts as an efficient lipophilic antioxidant along with vitamin E in long-lived termite *** study provides essential biochemical and evolutionary insights into the relationship between CoQ_(10) concentrations and termite lifespan extension.

关键词： antioxidant defense system coenzyme Q termite queens vitamin E

Highly efficient nitrogen fixation over S-scheme heterojunction photocatalysts with enhanced active hydrogen supply

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National Science Review 2024年第5期11卷 315-325页

作者： Tong Bao Yamin Xi Chaoqi Zhang Peiyang Du Yitong Xiang Jiaxin Li Ling Yuan Chengzhong Yu Chao Liu school of Chemistry and molecular Engineering East China Normal University Australian Institute for Bioengineering and Nanotechnology The University of Queensland

Photocatalytic N2fixation is a promising strategy for ammonia（NH3） synthesis;however,it suffers from relatively low ammonia yield due to the difficulty in the design of photocatalysts with both high charge transfer efficiency and desirable N2adsorption/activation ***,an S-scheme CoSx/ZnS heterojunction with dual active sites is designed as an efficient N2fixation *** CoSx/ZnS heterojunction exhibits a unique pocket-like nanostructure with small ZnS nanocrystals adhered on a single-hole CoSxhollow *** the heterojunction,the ele ctronic interaction between ZnS and CoSxcreates electron-deficient Zn sites with enhanced N2chemisorption and electron-sufficient Co sites with active hydrogen supply for N2hydrogenation,cooperatively reducing the energy barrier for *** combination with the promoted photogenerated electron-hole separation of the S-scheme heterojunction and facilitated mass transfer by the pocket-like nanostructure,an excellent N2fixation performance with a high NH3yield of 1175.37 μmol g-1h-1is *** study provides new insights into the design of hetero junction photocatalysts for N2fixation.

关键词： photocatalysis nitrogen fixation S-scheme heterojunction active hydrogen ammonia

Understanding of the structural evolution of catalysts and identification of active species during CO_(2) conversion

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Chinese Chemical Letters 2024年第4期35卷 17-30页

作者： Li Li Fanpeng Chen Bohang Zhao Yifu Yu Department of Chemistry School of ScienceInstitute of Molecular PlusTianjin UniversityTianjin 300072China

Converting CO_(2) into value-added chemicals and fuels through various catalytic methods to lower the atmospheric CO_(2) concentration has been developed to be a crucial means to alleviate the energy shortage and ameliorate the ever-fragile environment status. However, the complexity of the CO_(2) conversion reaction and the strong reduction conditions lead to the inevitable structural evolution, making it difficult for the prior design of suitable catalytic materials. Herein, to guide the rational design of efficient catalysts,we will be centered on the thermal, electro, and photo-induced structural evolution and active species identification during the CO_(2) conversion, including the in situ/operando characterization techniques monitoring the activation, steady, and deactivation stage of the catalysts as well as the inherent restructuring mechanism towards active species. Besides, the future challenges and opportunities on the merits of combining the structural evolution with the adsorbed intermediates recognized by ultra-fast spectroscopic techniques, simultaneously, the combination of theoretical simulation and the results of in situ experiments will also be addressed. This review can not only guide the identification of real active species, but also provide an approach to design the specific active species towards CO_(2) conversion, rather than only focusing on activity, for the purpose of practical industrial application.

关键词： CO_(2) Structural evolution Active species In situ Operando

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MarR family proteins sense sulfane sulfur in bacteria

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mLife 2024年第2期3卷 231-239页

作者： Guanhua Xuan Luying Xun Yongzhen Xia State Key Laboratory of microbial Technology Shandong UniversityQingdaoChina State Key Laboratory of Marine Food Processing&Safety Control Ocean University of ChinaQingdaoChina school of molecular biosciences Washington State UniversityPullmanWashingtonUSA

Members of the multiple antibiotic resistance regulator(MarR)protein family are ubiquitous in bacteria and play critical roles in regulating cellular metabolism and antibiotic *** family proteins function as repressors,and their interactions with modulators induce the expression of controlled *** previously characterized modulators are insufficient to explain the activities of certain MarR family ***,recently,several MarR family proteins have been reported to sense sulfane sulfur,including zero-valent sulfur,persulfide(R-SSH),and polysulfide(R-SnH,n≥2).Sulfane sulfur is a common cellular component in bacteria whose levels vary during bacterial *** changing levels of sulfane sulfur affect the expression of many MarR-controlled *** sulfur reacts with the cysteine thiols of MarR family proteins,causing the formation of protein thiol persulfide,disulfide bonds,and other *** MarR family proteins that respond to reactive oxygen species(ROS)also sense sulfane sulfur,as both sulfane sulfur and ROS induce the formation of disulfide *** review focused on MarR family proteins that sense sulfane ***,the sensing mechanisms reviewed here may also apply to other proteins that detect sulfane sulfur,which is emerging as a modulator of gene regulation.

关键词： cysteine thiols disulfide bond MarR protein family ROS sulfane sulfur

Simultaneous Bulk-and Surface-initiated Living Polymerization Studied with a Heterogeneous Stochastic Reaction Model

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Chinese Journal of Polymer Science 2024年第3期42卷 364-372,I0008页

作者： Jia-Shu Ma Zhi-Ning Huang Jia-Hao Li Bang-Ping Jiang Yan-Da Liao Shi-Chen Ji Xing-Can Shen State Key Laboratory for Chemistry and molecular Engineering of Medicinal Resources Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources(Ministry of Education of China)School of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541004China school of Computer Science and Engineering&school of Software Guangxi Normal UniversityGuilin 541004China

To better characterize the properties of surface-initiated polymers, simultaneous bulk-and surface-initiated polymerizations are usually carried out by assuming that the properties of the surface-initiated polymers resemble those of the bulk-initiated polymers. Through a Monte Carlo simulation using a heterogeneous stochastic reaction model, it was discovered that the bulk-initiated polymers exhibit a higher molecular weight and a lower dispersity than the corresponding surface-initiated polymers, which indicates that the equivalent assumption is invalid. Furthermore, the molecular weight distributions of the two types of polymers are also different, suggesting different polymerization mechanisms. The results can be simply explained by the heterogeneous distributions of reactants in the system. This study is helpful to better understand surface-initiated polymerization.

关键词： Surface-initiated polymerization Polymer brush Stochastic reaction model Heterogeneous polymerization Simultaneous polymerization

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Understanding neuroendocrine regulatory pathways of sexual behavior in teleosts

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Aquaculture and Fisheries 2024年第3期9卷 447-454页

作者： Saokat Ahamed Toshinobu Tokumoto Department of bioscience Graduate School of Science and TechnologyShizuoka UniversityOhya 836Suruga-kuShizuoka422-8529Japan

The main neuroendocrine pathways of induction of reproductive behavior in fish are elucidated.17α,20β-dihydroxy-4-pregnen-3-one (17,20β-DHP),an oocyte maturation-inducing hormone,was found to act as a pheromone to induce male reproductive behavior.17α,20β-DHP-sulfate (17,20β-DHP-S),a derivative of 17,20β-DHP,was also identified as a later-acting *** addition,prostaglandin F2 alpha (PGF2α),which is synthesized during female ovulation,has been shown to also act as a pheromone,inducing the final oviposition-inducing behavior to make fertilization *** appears that these molecular events are initiated by stimuli from the *** neuropeptides have been discovered that promote the initiation of reproductive ***,with the proliferation of genome editing technology,a detailed analysis of the molecules involved in these pathways is *** of gene knockout in zebrafish and medaka is actively *** the other hand,many research reports have shown that the induction pathways of male reproductive behavior are adversely affected by chemical *** of the adverse effects of chemical substances is not only useful as information to prevent their mixing from the viewpoint of protecting the natural environment and as a point of caution in fish farming,but also provides clues for elucidating the pathways of reproductive behavior *** elucidation of the pathways of reproductive behavior induction is also important from the point of view of breeding technology for fish farming and biodiversity *** this review,we summarize recent research on the pathways of male reproductive behavior induction in fish and the possibility of developing new aquaculture techniques depending on the results.

关键词： Fish male reproductive behavior Steroid hormone Pheromone 17,20β-DHP Prostaglandin Goldfish Zebrafish CRISPR/Cas9

Palladium-catalyzed vinylation of indoles with vinyl ethers via deoxygenative coupling

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Science China Chemistry 2024年第11期67卷 3785-3790页

作者： Bowen Wang Jianxiao Li Wanqing Wu Liangbin Huang Huanfeng Jiang Key Laboratory of Functional molecular Engineering of Guangdong Province School of Chemistry and Chemical EngineeringSouth China University of Technology

Indole is a promising heteroarene in many natural products and pharmaceuticals; therefore, various synthetic methods for indole functionalizations have arisen in recent years. Herein, we report a Pd-catalyzed deoxygenative coupling for the N-vinylation of indoles by employing vinyl ethers. The vinylated indoles could be readily prepared in good to excellent yields with N1-regioselectivity regardless of the electronic characteristics and substitution patterns of indole substrates. Some indole-based pharmaceutical molecules, such as gramine, evodiamine, rutaecarpine, and melatonine, are also successfully vinylated. Moreover, carbazoles and indazoles are shown to participate. Additionally, vinylated indole can readily transform into structurally interesting indole derivatives.

关键词： indole vinylation regioselectivity N-vinyl indole palladium catalyst

Competitive intermetallics formation in Pd-Zn-Cd system via seeded growth from ultra-thin Pd nanosheets for electrocatalytic ethanol oxidation reaction

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Nano Research 2024年第9期17卷 8552-8559页

作者： Donghao Zhang Lianxi Si Qianqian Ren Xintong Yan Shi Hu Department of Chemistry School of ScienceTianjin Key Laboratory of Molecular Optoelectronic ScienceTianjin UniversityTianjin 300072China

Pd-based catalysts exhibit higher catalytic activity and durability in many electrochemical ***,the electrochemical performance can be further enhanced by fine-tune of the alloy *** binary alloys have been fully studied,the multicomponent alloys are far beyond understanding,which leaves cocktail effect a compromised explanation for the high-entropy *** Pd nanosheet-seeded growth was used to synthesize a Pd-Zn-Cd ternary alloy by accurately controlling the Pd-Zn-Cd molar ratio through adjusting the amount of introduced Cd *** analysis of the crystal phase structure of PdCdZnx and PdZn_(x)Cd_(1-x),the competitive relationship of Zn and Cd in the alloying process with Pd was unveiled:Pd1Cd1 intermetallics(IMC)is thermodynamically favored over Pd_(1)Zn_(1)IMC in the ternary ***,the increased structure stability of PdCd over PdZn does not bring about increased durability in the catalytic ethanol oxidation *** morphology selection of Pd seeds is also crucial for the study,as Pd cubes,Pd tetrahedrons,and Pd octahedrons do not form PdZn in the same *** successful alloying through the seeded growth depends on the maximum diffusion depth of foreign atoms into the seed.

关键词： PdZn alloy seed growth method ethanol oxidation reaction composition control ternary alloying

Post-treatment of Ti-MWW zeolite with potassium fluoride for propylene epoxidation

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Frontiers of Chemical Science and Engineering 2024年第8期18卷 37-47页

作者： Xintong Li Xianchen Gong Jilong Wang Shengbo Jin Hao Xu Peng Wu State Key Laboratory of Petroleum molecular&Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China

Epoxidation of propylene to propylene oxide(PO)with hydrogen peroxide(HPPO)is an environmentally friendly and cost-efficient process in which titanosilicates are used as ***-MWW is a potential industrial catalyst for this process,which involves the addition of HPPO to *** silanol groups generated during secondary crystallization unavoidably result in ring-opening of PO and inefficient decomposition of HPPO,which diminish the PO selectivity and the lifespan of *** address this issue,we conducted post-treatment modifications of the structured Bf-Ti-MWW catalyst with potassium fluoride aqueous *** quenching the silanol groups with potassium fluoride and implanting electron-withdrawing fluoride groups into the Ti-MWW framework,both the catalytic activity and HPPO utilization efficiency were ***,the ring opening reaction of PO was *** a continuous fixed-bed liquid-phase propylene epoxidation reaction,the KF-treated structured Ti-MWW catalyst displayed an exceptionally long lifespan of 2700 h,with a PO yield of 590 g·kg^(-1)·h^(-1).

关键词： titanosilicates Ti-MWW propylene epoxidation structured catalyst KF modification