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Serrated flow behavior of GH536 superalloy under different loading rates at room temperature

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Rare Metals 2024年第5期43卷 2317-2323页

作者： wen-Xiang Gao Dong Ma Li-Li Zhao Fan ye Ling Shao Su-Jun Wu School of Materials Science and Technology Beihang UniversityBeijing100091China

Serrated flow phenomenon has been widely observed among different metals due to the potential influence on their *** tensile tests of nickel-based superalloy GH536 were carried out at loading rates of 0.06,0.60,3.60,and 36.00 mm·min^(-1)at room temperature,*** tensile stress-strain curves demonstrate repetitive and discontinuous yielding behavior,namely serrated *** is observed that the stress-strain curves were dominated by type B serration,and original annealing twin boundaries(TBs)were distorted to various degrees under comparatively different lower tensile *** contrast,the TBs almost disappear,and the type B serrations become smoother and regular under the higher loading *** phenomenon can be attributed to the interactions between TBs and dislocations during tensile *** effects of the mobile and immobile dislocations illustrate the unsteady amplitude of serrations observed in stress-strain *** electron microscope images of tested pieces reveal the interaction of dislocation and TB,with dislocation tangling around the TBs.

关键词： Nickel-based superalloy Serrations Twin boundaries Deformation mechanism

Mesenchymal stem cell therapy for liver fibrosis need“partner”:Results based on a meta-analysis of preclinical studies

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World Journal of Gastroenterology 2024年第32期30卷 3766-3782页

作者： Yan Xu Xue-Song Wang Xiao-Lei Zhou wen-Ming Lu Xing-Kun Tang Yu jin Jun-Song ye Subcenter for Stem Cell Clinical Translation First Affiliated Hospital of Gannan Medical UniversityGanzhou 341000Jiangxi ProvinceChina School of Rehabilitation Medicine Gannan Medical UniversityGanzhou 341000Jiangxi ProvinceChina Ganzhou Key Laboratory of Stem Cell and Regenerative Medicine Gannan Medical UniversityGanzhou 341000Jiangxi ProvinceChina Department of Medical Genetics School of MedicineTongji UniversityShanghai 200092China Key Laboratory of Prevention and Treatment of Cardiovascular and Cerebrovascular Diseases Ministry of EducationGannan Medical UniversityGanzhou 341000Jiangxi ProvinceChina

BACKGROUND The efficacy of mesenchymal stem cells(MSCs)in treating liver fibrosis has been demonstrated in several clinical ***,their low survival and liver implantation rates remain *** recent years,a large number of studies in animal models of liver fibrosis have shown that MSCs combined with drugs can improve the efficacy of MSCs in the treatment of liver fibrosis alone and inhibit its progression to end-stage liver *** has inspired new ways of thinking about treating liver *** To investigate the effectiveness and mechanisms of MSCs combined with drugs in treating liver *** Data sources included four electronic databases and were constructed until January *** subjects,interventions,comparators,outcomes,and study design principle were used to screen the literature,and the quality of the literature was evaluated to assess the risk of *** randomised controlled trials were selected,and the final 13 studies were included in the final *** A total of 13 studies were included after *** analysis showed that MSCs combined with drug therapy significantly improved liver function,promoted the repair of damaged liver tissues,reduced the level of liver fibrosis-related indexes,and effectively ameliorated hepatic fibrosis by modulating the hepatic inflammatory microenvironment,promoting the homing of MSCs,and regulating the relevant signaling pathways,and the treatment efficacy was superior to MSCs ***,the combined treatment statistics showed no amelioration in serum albumin levels(standardized mean difference=0.77,95%confidence interval:-0.13 to 1.68,P=0.09).CONCLUSION In conclusion,MSCs combined with drugs for treating liver fibrosis effectively make up for the shortcomings of MSCs in their therapeutic ***,due to the different drugs,the treatment mechanism and effect also ***,more randomized controlled trials are needed to compare the therapeutic effic

关键词： drugs alone partner

Progress in systematics and biogeography of Orchidaceae

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Plant Diversity 2024年第4期46卷 425-434页

作者： Yajun Wang Hanchen Wang Chao ye Zhiping Wang Chongbo Ma Dongliang Lin Xiaohua jin State Key Laboratory of Plant Diversity and Specialty Crops Institute of Botanythe Chinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100093China China National Botanical Garden Beijing 100093China

Orchidaceae are one of the largest families of angiosperms in terms of species *** the last decade,numerous studies have delved into reconstructing the phylogenetic framework of Orchidaceae,leveraging data from plastid,mitochondrial and nuclear *** studies have provided new insights into the systematics,diversification and biogeography of Orchidaceae,establishing a robust foundation for future ***,pronounced controversies persist regarding the precise placement of certain lineages within these phylogenetic *** address these discrepancies and deepen our understanding of the phylogenetic structure of Orchidaceae,we provide a comprehensive overview and analysis of phylogenetic studies focusing on contentious groups within Orchidaceae since 2015,delving into discussions on the underlying reasons for observed topological *** also provide a novel phylogenetic framework at the subtribal ***,we examine the tempo and mode underlying orchid species diversity from the perspective of historical biogeography,highlighting factors contributing to extensive ***,we delineate avenues for future research aimed at enhancing our understanding of Orchidaceae phylogeny and diversity.

关键词： Diversification Orchid phylogenetics Phylogenetic conflicts Biogeography Taxonomy

Anchoring Ru clusters to highly defective N-doped carbon nanotubes via a thermal-shock strategy for stable industrial hydrogen evolution

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Nano Research 2024年第6期17卷 5261-5269页

作者： Zhiming Li Xinyu Li Haiqing Ma Chenliang ye Hongan Yu Long Nie Meng Zheng jin Wang College of Materials Science and Engineering Shenzhen UniversityShenzhen 518060China School of Chemistry and Materials Science Anhui Normal UniversityWuhu 241002China Department of Power Engineering North China Electric Power UniversityBaoding 071003China

Non-Pt or low-Pt catalysts capable for stable generation of hydrogen via water electrolysis at an industrial level of current density are highly *** of strong metal-support connection is beneficial to improve the performance stability of *** we employed highly defective N-doped carbon nanotubes(d-N-CNT)as the support to achieve uniform and firm anchoring of Ru clusters(~1.9 nm)via a thermal-shock *** as-prepared Ru/d-N-CNT catalyst shows excellent catalytic activity for hydrogen evolution reaction(HER)in alkaline media and requires an overpotential(ƞ)of 12 mV at 10 mA·cm^(−2)and 116 mV at 200 mA·cm^(−2)with a Ru loading of 0.025 mg·cm^(−2).Impressively,Ru/d-N-CNT presents robust stability for HER at both low current density(stable for at least 1000 h at 10 mA·cm^(−2))and the industrial level of current density(stable for at least 100 h at 1000 mA·cm^(−2)),remarkably outperforming commercial Pt/C and Ru/*** highly defective nature of the N-CNT support endowed the as-prepared Ru/d-N-CNT catalyst with strong metal-support adhesion that efficiently suppressed agglomeration as well as obscission of Ru ***,the rich defects increased the surface energy of the N-CNT support and resulted in improved hydrophilicity as evidenced by the liquid contact angle measurement and the bubble evolution process,which also played an important role in stabilizing the HER performance especially at large current density.

关键词： thermal-shock method hydrogen evolution reaction large-current-density Ru cluster

Effect of interrupted aging on mechanical properties and corrosion resistance of 7A75 aluminum alloy

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Transactions of Nonferrous Metals Society of China 2024年第8期34卷 2415-2430页

作者： Xian-wen YANG Ling-ying ye Yong ZHANG Quan-shi CHENG School of Materials Science and Engineering Central South UniversityChangsha 410083China Aerospace Precision Production Co. Ltd.Tianjin 300300China

The effects of interrupted aging on mechanical properties and corrosion resistance of 7A75 aluminum alloy extruded bar were investigated through various analyses,including electrical conductivity,mechanical properties,local corrosion properties,and slow strain rate tensile stress corrosion *** characterization techniques such as metallographic microscopy,scanning electron microscopy(SEM),and transmission electron microscopy(TEM)were also *** results indicate that the tensile strength of the alloy produced by T6I6 aging is similar to that produced by T6I4 aging,and it even exceeds 700 ***,the yield strength increases by 52.7 MPa,reaching 654.8 MPa after T6I6 aging *** maximum depths of intergranular corrosion(IGC)and exfoliation corrosion(EXCO)decrease from 116.3 and 468.5μm to 89.5 and 324.3μm,*** stress corrosion factor also decreases from 2.1%to 1.6%.These findings suggest that the alloy treated with T6I6 aging exhibits both high strength and excellent stress corrosion cracking ***,when the alloy is treated with T6I4,T6I6 and T6I7 aging,the sizes of grain boundary precipitates(GBPs)are found to be 5.2,18.4,and 32.8 nm,*** sizes of matrix precipitates are 4.8,5.7 and 15.7 nm,*** atomic fractions of Zn in GBPs are 9.92 at.%,8.23 at.%and 6.87 at.%,respectively,while the atomic fractions of Mg are 12.66 at.%,8.43 at.%and 7.00 at.%,***,the atomic fractions of Cu are 1.83 at.%,2.47 at.%and 3.41 at.%,respectively.

关键词： 7A75 aluminum alloy interrupted aging aging precipitation behavior mechanical properties intergranular corrosion exfoliation corrosion stress corrosion cracking

Chemical and mechanical properties of stainless, environment-friendly, and nonflammable Mg alloys (SEN alloys): A review

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Journal of Magnesium and Alloys 2024年第3期12卷 841-872页

作者： Jong Un Lee Hyun Ji Kim Sang-Cheol jin ye jin Kim Young Min Kim Bong Sun You Jun Ho Bae Sung Hyuk Park Advanced Metals Division Korea Institute of Materials ScienceChangwon 51508Republic of Korea Department of Materials Science and Metallurgical Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Missile Research Institute Agency for Defense DevelopmentDaejeon 34060Republic of Korea

This review article provides overall understanding of stainless,environment-friendly,and nonflammable Mg alloys(SEN alloys)recently developed at the Korea Institute of Materials *** alloys are produced by adding small amounts of Ca and Y(eachyer of SEN alloys comprising MgO,CaO,and Y_(2)O_(3) impedes the outward dispersion of Mg vapor and the inward penetration of O_(2) during oxidation,thereby enhancing the oxidation and ignition resistances.(2)The presence of Ca-and Y-based second-phase particles in SEN alloys can enhance their corrosion resistance because Ca-containing particles prevent the spread of corrosion,and the replacement of Al-containing particles with less noble ones containing Y(e.g.,Al–Mn–Y or Al–Y particles)retards corrosion.(3)The addition of minor amounts of Ca and Y renders excellent mechanical properties due to improved strengthening *** enhanced properties are attributed to more pronounced dynamic recrystallization and grain refining behaviors caused by the second-phase particles during extrusion.(4)Despite the presence of various types of second-phase particles,the fatigue properties of SEN9 alloys are similar to those of commercial AZ91 alloys.(5)Simultaneous introduction of Ca and Y suppresses the formation of Mg17Al12 discontinuous precipitates during aging,leading to the enhanced elongation of aged SEN alloys.(6)Adding mischmetal into the SEN9 alloy leads to a six-fold enhancement in ***,the studies conducted on SEN alloys demonstrate their excellent ignition and corrosion resistances and mechanical properties,which broaden the industrial applications of Mg alloys by addressing their inherent weaknesses.

关键词： SEN magnesium alloy Corrosion resistance Ignition resistance Mechanical properties Extrudability.

Alkaline sphingomyelinase deficiency impairs intestinal mucosal barrier integrity and reduces antioxidant capacity in dextran sulfate sodium-induced colitis

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World Journal of Gastroenterology 2024年第10期30卷 1405-1419页

作者： ye Tian Xin Li Xu Wang Si-Ting Pei Hong-Xin Pan Yu-Qi Cheng Yi-Chen Li wen-Ting Cao jin-Dong Ding Petersen Ping Zhang International School of Public Health and One Health Hainan Medical UniversityHaikou 571199Hainan ProvinceChina Medical Laboratory Science and Technology College Harbin Medical University-Daqing CampusDaqing 163000Heilongjiang ProvinceChina Department of Laboratory Diagnosis Qiqihar Tuberculosis Control CenterQiqihar 161000Heilongjiang ProvinceChina Department of Public Health University of CopenhagenCopenhagen 1353Denmark Department of Public Health University of Southern DenmarkOdense 5000Denmark

BACKGROUND Ulcerative colitis is a chronic inflammatory disease of the colon with an unknown *** sphingomyelinase(alk-SMase)is specifically expressed by intestinal epithelial cells,and has been reported to play an anti-inflammatory ***,the underlying mechanism is still *** To explore the mechanism of alk-SMase anti-inflammatory effects on intestinal barrier function and oxidative stress in dextran sulfate sodium(DSS)-induced *** Mice were administered 3%DSS drinking water,and disease activity index was determined to evaluate the status of *** permeability was evaluated by gavage administration of fluorescein isothiocyanate dextran,and bacterial translocation was evaluated by measuring serum *** epithelial cell ultrastructure was observed by electron *** blotting and quantitative real-time reverse transcription-polymerase chain reaction were used to detect the expression of intestinal barrier proteins and mRNA,*** oxidant and antioxidant marker levels were analyzed using commercial kits to assess oxidative stress *** Compared to wild-type(WT)mice,inflammation and intestinal permeability in alk-SMase knockout(KO)mice were more severe beginning 4 d after DSS *** mRNA and protein levels of intestinal barrier proteins,including zonula occludens-1,occludin,claudin-3,claudin-5,claudin-8,mucin 2,and secretory immunoglobulin A,were significantly reduced on 4 d after DSS *** observations revealed progressive damage to the tight junctions of intestinal epithelial ***,by day 4,mitochondria appeared swollen and ***,compared to WT mice,serum malondialdehyde levels in KO mice were higher,and the antioxidant capacity was significantly *** expression of the transcription factor nuclear factor erythroid 2-related factor 2(Nrf2)in the colonic mucosal tissue of KO mice was significantly decr

关键词： Alkaline sphingomyelinase Intestinal mucosal barrier Antioxidant capacity Dextran sulfate sodium-induced colitis nuclear factor erythroid 2-related factor 2

Nitro-oleic acid ameliorates erectile dysfunction in a streptozotocin-induced rat model of diabetes by inhibiting oxidative stress and apoptosis and activating the NO/cGMP pathway

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Asian Journal of Andrology 2024年第1期26卷 57-66页

作者： Chang-Bo Zhao Wei-Bo Chen wen-Zhen Wang Fang-Xin Gong Cui-Qin Fan ye Li Tian Lan wen-jing Wang Ming-Zhen Yuan Department of Urology Shandong Provincial HospitalShandong UniversityJinan 250012China Department of Andrology Liaocheng People's HospitalShandong UniversityLiaocheng 252000China Department of Urology The Second Hospital of Shandong UniversityJinan 250012China Department of Physiology School of Basic Medical SciencesShandong UniversityJinan 250012China

The major vascular complications associated with diabetes make the management of diabetic mellitus erectile dysfunction(DMED)a challenging *** factors contributing to DMED include oxidative stress,nitric oxide(NO)/cyclic guanosine monophosphate(cGMP)pathway activation,and apoptosis,while nitro-oleic acid(NO,-OA)has been shown to be beneficial in treating these aspects of this ***,herein,investigated the effects and possible mechanisms of NO,-OA on erectile function as assessed in a streptozotocin-induced rat model of *** results revealed that the erectile function of DMED rats was significantly impaired compared with that of the control ***,in response to 4 weeks of NO,-OA treatment,there was an improvement in erectile *** expression of oxidative stress-related indicators was significantly increased and the NO/cGMP pathway was impaired in the DMED *** expression of proapoptotic factors was increased,while that of antiapoptotic factors was decreased in the DMED ***,the cell morphology in the cavernous tissue of the DMED group also changed ***,-OA treatment significantly reversed all these changes observed in the DMED *** conclusion,NO,-OA treatment partially improved erectile function in DMED rats through mechanisms that included inhibition of oxidative stress,activation of the NO/cGMP pathway,and a reduction in apoptosis.

关键词： apoptosis diabetic mellitus erectile dysfunction nitro-oleic acid NO/cGMP pathway oxidative stress

Unlocking the potential of amorphous calcium carbonate: A star ascending in the realm of biomedical application

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Acta Pharmaceutica Sinica B 2024年第2期14卷 602-622页

作者： Han Liu Zhiyang wen Zihan Liu Yanfang Yang Hongliang Wang Xuejun Xia Jun ye Yuling Liu State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China Beijing Key Laboratory of Drug Delivery Technology and Novel Formulation Institute of Materia MedicaChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

Calcium-based biomaterials have been intensively studied in the field of drug delivery owing to their excellent biocompatibility and ***-based materials can also deliver contrast agents,which can enhance real-time imaging and exert a Ca^(2+)-interfering therapeutic *** on these characteristics,amorphous calcium carbonate(ACC),as a brunch of calcium-based biomaterials,has the potential to become a widely used *** functional ACC can be either discovered in natural organisms or obtained by chemical synthesis However,the standalone presence of ACC is unstable in *** are required to be used as stabilizers or core-shell structures formed by permeable layers or lipids with modified molecules constructed to maintain the stability of ACC until the ACC carrier reaches its *** has high chemical instability and can produce biocompatible products when exposed to an acidic condition in vivo,such as Ca^(2+) with an immune-regulating ability and CO_(2) with an imaging-enhancing *** to these characteristics,ACC has been studied for selfsacrificing templates of carrier construction,targeted delivery of oncology drugs,immunomodulation,tumor imaging,tissue engineering,and calcium *** in this paper has been placed on the origin,structural features,and multiple applications of ***,ACC faces many challenges in clinical translation,and long-term basic research is required to overcome these *** hope that this study will contribute to future innovative research on ACC.

关键词： Amorphous calcium carbonate Drugdelivery system Nanoparticle Acid sensitivity Water instability,Tumortherapy Tissue engineering Calcium supplement