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Oxygen vacancy engineering for tuning the catalytic activity of LaCoO_(3) perovskite

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Journal of Rare Earths 2024年第3期42卷 506-514,I0003页

作者： Jeong Hyun Cho Minjae Kim Inchan Yang Kyung Tae park Chang Houn Rhee Hai Woong park Ji chul Jung Department of Chemical Engineering Myongji UniversityYongin 17058Republic of Korea Institute of Advanced Composite Materials Korea Institute of Science and TechnologyWanju-gunJeollabuk-do 55324Republic of Korea Iron&Steel Process Engineering Research Group POSCOPohang 37859Republic of Korea Hydrogen Research Center Research Institute of Industrial Science&Technology(RIST)Pohang 37673Republic of Korea

Herein, we attempted to engineer oxygen vacancies on the surface of LaCoO_(3) perovskite through simple post-treatments(acid or reductive thermal treatments). Acid treatment induces oxygen vacancies through the selective etching of the La cations, whereas thermal treatment in a reducing atmosphere generates oxygen vacancies by directly removing lattice oxygen. The characterization results confirm that the number of surface oxygen vacancies, which are crucial in various catalytic oxidation reactions,considerably increases in the LaCoO_(3) catalysts treated with acid or reducing gas. Acid treatment enriches the oxygen vacancies while maintaining the structure of the LaCoO_(3) catalysts, which can not be achieved through reductive thermal treatment. Therefore, the acid treatment is considered a promising technique for oxygen vacancy engineering of perovskite catalysts for tuning their catalytic activities. Furthermore,the catalytic activities of the posttreated LaCoO_(3) catalysts for CO oxidation were evaluated and are noted to be considerably better than those of the pristine LaCoO_(3) catalyst due to their abundant oxygen vacancies. Consequently, we conclude that the oxygen vacancies of perovskite catalysts can be effectively engineered via two simple methods and play a significant role in CO oxidation.

关键词： LaCoO_(3)perovskite Acid treatment Reductive thermal treatment Oxygen vacancy CO oxidation Rare earths

Effects of mesenchymal stem cell on dopaminergic neurons,motor and memory functions in animal models of parkinson's disease:a systematic review and meta-analysis

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Neural Regeneration Research 2024年第7期19卷 1584-1592页

作者： Jong Mi park Masoud Rahmati Sang chul Lee Jae Il Shin Yong Wook Kim Department and Research Institute of Rehabilitation Medicine Yonsei University College of MedicineSeoulSouth Korea Department of Physical Education and Sport Sciences Faculty of Literature and Human SciencesLorestan UniversityKhoramabadIran Department of Pediatrics Yonsei University College of MedicineSeoulSouth Korea

parkinson’s disease is chara cterized by the loss of dopaminergic neurons in the substantia nigra pars com pacta,and although restoring striatal dopamine levels may improve symptoms,no treatment can cure or reve rse the disease *** cell therapy has a regenerative effect and is being actively studied as a candidate for the treatment of parkinson’s *** stem cells are considered a promising option due to fewer ethical concerns,a lower risk of immune rejection,and a lower risk of *** performed a meta-analysis to evaluate the therapeutic effects of mesenchymal stem cells and their derivatives on motor function,memory,and preservation of dopamine rgic neurons in a parkinson’s disease animal *** searched bibliographic databases(PubMed/MEDLINE,Embase,CENTRAL,Scopus,and Web of Science)to identify articles and included only pee r-reviewed in vivo interve ntional animal studies published in any language through J une 28,*** study utilized the random-effect model to estimate the 95%confidence intervals(CI)of the standard mean differences(SMD)between the treatment and control *** use the systematic review center for laboratory animal expe rimentation’s risk of bias tool and the collaborative approach to meta-analysis and review of animal studies checklist for study quality assessment.A total of 33studies with data from 840 parkinson’s disease model animals were included in the *** with mesenchymal stem cells significantly improved motor function as assessed by the amphetamine-induced rotational *** the stem cell types,the bone marrow MSCs with neurotrophic factor group showed la rgest effect size(SMD[95%CI]=-6.21[-9.50 to-2.93],P=0.0001,I^(2)=0.0%).The stem cell treatment group had significantly more tyrosine hydroxylase positive dopamine rgic neurons in the striatum([95%CI]=1.04[0.59 to 1.49],P=0.0001,I^(2)=65.1%)and substantia nigra(SMD[95%CI]=1.38[0.89 to 1.87],P=0.0001,I^(2)=75.3%),indicating a

关键词： animal animal experimentation mesenchymal stem cells models parkinson’s disease stem cell transplantation

Efficient Electromagnetic Wave Absorption and Thermal Infrared Stealth in PVTMS@MWCNT Nano‑Aerogel via Abundant Nano‑Sized Cavities and Attenuation Interfaces

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Nano-Micro Letters 2024年第1期16卷 370-383页

作者： Haoyu Ma Maryam Fashandi Zeineb Ben Rejeb Xin Ming Yingjun Liu Pengjian Gong Guangxian Li chul B.park College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan University24 Yihuan RoadNanyiduanChengdu 610065SichuanPeople’s Republic of China Microcellular Plastics Manufacturing Laboratory Department of Mechanical and Industrial EngineeringUniversity of Toronto5 King’s College RoadTorontoON M5S 3G8Canada Jiangsu JITRI Advanced Polymer Materials Research Institute Tengfei Building88 Jiangmiao RoadJiangbei New DistrictNanjing 211800JiangsuPeople’s Republic of China MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringInternational Research Center for X PolymersZhejiang University38 Zheda RoadHangzhou 310027People’s Republic of China

Pre-polymerized vinyl trimethoxy silane(PVTMS)@MWCNT nano-aerogel system was constructed via radical polymerization,sol-gel transition and supercritical CO_(2)*** fabricated organic-inorganic hybrid PVTMS@MWCNT aerogel structure shows nano-pore size(30-40 nm),high specific surface area(559 m^(2)g^(−1)),high void fraction(91.7%)and enhanced mechanical property:(1)the nano-pore size is beneficial for efficiently blocking thermal conduction and thermal convection via Knudsen effect(beneficial for infrared(IR)stealth);(2)the heterogeneous interface was beneficial for IR reflection(beneficial for IR stealth)and MWCNT polarization loss(beneficial for electromagnetic wave(EMW)attenuation);(3)the high void fraction was beneficial for enhancing thermal insulation(beneficial for IR stealth)and EMW impedance match(beneficial for EMW attenuation).Guided by the above theoretical design strategy,PVTMS@MWCNT nano-aerogel shows superior EMW absorption property(cover all Ku-band)and thermal IR stealth property(ΔT reached 60.7℃).Followed by a facial combination of the above nano-aerogel with graphene film of high electrical conductivity,an extremely high electromagnetic interference shielding material(66.5 dB,2.06 mm thickness)with superior absorption performance of an average absorption-to-reflection(A/R)coefficient ratio of 25.4 and a low reflection bandwidth of 4.1 GHz(A/R ratio more than 10)was experimentally obtained in this work.

关键词： Nano-pore size Heterogeneous interface Electromagnetic wave absorption Thermal infrared stealth Nano-aerogel

Methane Emission from Rice Fields:Necessity for Molecular Approach for Mitigation

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Rice science 2024年第2期31卷 159-178页

作者： Sujeevan RAJENDRAN Hyeonseo park Jiyoung KIM Soon Ju park Dongjin SHIN Jong-Hee LEE Young Hun SONG Nam-Chon PAEK chul Min KIM Department of Horticulture Industry Wonkwang UniversityIksan 54538Korea Plant Molecular Biology and Biotechnology Research Center Gyeongsang National UniversityJinju 52828Korea Department of Southern Area Crop Science National Institute of Crop ScienceMiryang 50424Korea Department of Agricultural Biotechnology Seoul National UniversitySeoul 08826Korea Department of Plant Science Plant Genomics and Breeding InstituteResearch Institute of Agriculture and Life SciencesSeoul National UniversitySeoul 08826Korea

Anthropogenic methane emissions are a leading cause of the increase in global averagetemperatures,often referred to as global *** soils play a significant role in methaneproduction,where the anaerobic conditions promote the production of methane by *** fields contribute a considerable portion of agricultural methane emissions,as riceplants provide both factors that enhance and limit methane *** plants harbor both methaneproducingand methane-oxidizing *** from rice roots provide source for methaneproduction,while oxygen delivered from the root aerenchyma enhances methane *** haveshown that the diversity of these microorganisms depends on rice cultivars with some genes characterizedas harboring specific groups of microorganisms related to methane ***,there is still aneed for research to determine the balance between methane production and oxidation,as rice plantspossess the ability to regulate net methane *** agronomical practices,such as fertilizerand water management,have been employed to mitigate methane ***,studiescorrelating agronomic and chemical management of methane with productivity are ***,evidences for breeding low-methane-emitting rice varieties are scattered largely due to the absence ofcoordinated breeding *** has indicated that phenotypic characteristics,such as rootbiomass,shoot architecture,and aerenchyma,are highly correlated with methane *** reviewdiscusses available studies that involve the correlation between plant characteristics and *** emphasizes the necessity and importance of breeding low-methane-emitting rice varieties inaddition to existing agronomic,biological,and chemical *** review also delves into the idealphenotypic and physiological characteristics of low-methane-emitting rice and potential breeding techniques,drawing from studies conducted

关键词： methane emission rice breeding aerenchyma greenhouse gas radial oxygen loss

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全球国际收支失衡与新兴市场

国际经济评论 2006年第5期 45-48页

作者： yung chul park 樊纲 David Vines 韩国首尔大学全球商业和金融研究中心国民经济研究所牛津大学

十个亚洲经济体，包括中国、日本以及四个最新的工业化国家和地区——就是东亚的四个经济体，还有其他的东盟国家，他们的外汇储备合起来已经达到了2．6万亿（整理者注：这是2006年3月末数字）。在过去的几个月当中，我们可以看到：虽... 详细信息

十个亚洲经济体，包括中国、日本以及四个最新的工业化国家和地区——就是东亚的四个经济体，还有其他的东盟国家，他们的外汇储备合起来已经达到了2．6万亿（整理者注：这是2006年3月末数字）。在过去的几个月当中，我们可以看到：虽然外汇储备的增加量不像过去那么明显，但是我们仍然可以通过这样一个数字看到，中国和日本在外汇储备中占了66％，而那些新兴的工业化国家和地区占了28％，其他的东盟国家占了差不多7％。

关键词：国际收支失衡新兴市场亚洲经济体工业化国家全球外汇储备东盟国家中国

全球国际收支失衡的可持续性、调整时机与对策建议

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国际经济评论 2006年第5期 62-64页

作者： Jean Pisani-Ferry yung chul park Naoyuki Yoshino 唐旭布鲁塞尔欧洲和全球经济实验室韩国首尔大学日本庆应大学中国人民银行研究局

全球国际收支失衡是我们讨论的一个出发点，对此我们有着明显不同的观点。总的来说，我们没有考虑到美国国际收支失衡的可持续性。我们提到了有关解决全球国际收支失衡的一些问题和概念，比如美国的资产回报率可能比较高等问题；前面的... 详细信息

全球国际收支失衡是我们讨论的一个出发点，对此我们有着明显不同的观点。总的来说，我们没有考虑到美国国际收支失衡的可持续性。我们提到了有关解决全球国际收支失衡的一些问题和概念，比如美国的资产回报率可能比较高等问题；前面的讨论主要是考虑到亚洲的顺差，特别是中国的顺差；有时候政策制订者会对危机做出过度反应；余永定也提到中国实际上并不想拥有太多的外汇储备。

关键词：国际收支失衡可持续性全球资产回报率政策制订者过度反应外汇储备美国

Ethyl acetate fraction of Sargassum pallidum extract attenuates particulate matter-induced oxidative stress and inflammation in keratinocytes and zebrafish

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Asian Pacific Journal of Tropical Biomedicine 2024年第4期14卷 137-146页

作者： Wook chul Kim Ji-Won park Bohyun Yun WonWoo Lee Kyung-Min Choi Seung-Hong Lee Department of Medical Science Soonchunhyang UniversityAsan 31538Republic of Korea Honam National Institute of Biological Resources 99Gohadoan-gilMokpo-siJeollanam-do 58762Republic of Korea Department of Pharmaceutical Engineering Soonchunhyang UniversityAsan 31538Republic of Korea

Objective:To evaluate the effect of the ethyl acetate fraction derived from Sargassum pallidum extract against particulate matter(PM)-induced oxidative stress and inflammation in HaCaT cells and ***:HaCaT cells and zebrafish were used to evaluate the protective effects of the ethyl acetate fraction of Sargassum pallidum extract against PM-induced oxidative stress and *** production of nitric oxide(NO),intracellular ROS,prostaglandin E_(2)(PGE_(2)),and pro-inflammatory cytokines,and the expression levels of COX-2,iNOS,and NF-κB were evaluated in PM-induced HaCaT ***,the levels of ROS,NO,and lipid peroxidation were assessed in the PM-exposed zebrafish ***:The ethyl acetate fraction of Sargassum pallidum extract significantly decreased the production of NO,intracellular ROS,and PGE_(2) in PM-induced HaCaT *** addition,the fraction markedly suppressed the levels of pro-inflammatory cytokines and inhibited the expression levels of COX-2,iNOS,and NF-κ***,it displayed remarkable protective effects against PM-induced inflammatory response and oxidative stress,represented by the reduction of NO,ROS,and lipid peroxidation in ***:The ethyl acetate fraction of Sargassum pallidum extract exhibits a protective effect against PM-induced oxidative stress and inflammation both in vitro and in vivo and has the potential as a candidate for the development of pharmaceutical and cosmeceutical products.

关键词： Particulate matter Inflammation Oxidative stress Sargassum pallidum Ethyl acetate fraction Zebrafish

Capsosiphon fulvescens suppresses LPS-stimulated inflammatory responses by suppressing TLR4/NF-κB activation in RAW264.7 murine macrophages

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Asian Pacific Journal of Tropical Biomedicine 2024年第3期14卷 115-126页

作者： Seon Yeong Ji EunJin Bang Hyun Hwangbo Min Yeong Kim Da Hye Kim Su Hyun Hong Shin-Hyung park Chang-Young Kwon Gi-Young Kim You-Jin Jeon Suengmok Cho yung Hyun Choi Department of Biochemistry Dong-eui University College of Korean MedicineBusan 47227Republic of Korea Basic Research Laboratory for the Regulation of Microplastic-Mediated Diseases and Anti-Aging Research Center Dong-eui UniversityBusan 47227Republic of Korea Department of Pathology Dong-eui University College of Korean MedicineBusan 47227Republic of Korea Department of Oriental Neuropsychiatry Dong-eui University College of Korean MedicineBusan 47227Republic of Korea Department of Marine Life Science Jeju National UniversityJeju 63243Republic of Korea Department of Food Science and Technology/Institute of Food Science Pukyong National UniversityBusan 48513Republic of Korea

Objective:To evaluate the effects of Capsosiphon fulvescens(***)ethanolic extract on inflammation in lipopolysaccharide(LPS)-induced RAW296.7 ***:The protective effects of *** ethanolic extract on LPS-induced inflammation in RAW264.7 macrophages were assessed using biochemical analysis,including enzyme-linked immunosorbent assay,quantitative reverse transcription-polymerase chain reaction,and Western blot *** examine reactive oxygen species(ROS)production,flow cytometry analysis,and immunofluorescence staining were ***,the modulatory effect of *** ethanolic extract on NF-κB activation was ***:*** ethanolic extract significantly attenuated LPS-induced levels of pro-inflammatory cytokines and notably reduced the secretion and mRNA levels of LPS-mediated matrix *** addition,*** ethanolic extract decreased ROS production and suppressed the TLR4/NF-κB signaling ***:*** ethanolic extract alleviates inflammation as well as oxidative stress by modulating the TLR4/NF-κB signaling in LPS-induced RAW264.7 *** can be used as a potential therapeutic agent to suppress inflammation and oxidative stress-associated diseases.

关键词： Capsosiphon fulvescens Inflammation Oxidative stress NF-κB Nrf2 TLR4

Functionally graded structure of a nitride-strengthened Mg_(2)Si-based hybrid composite

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Journal of Magnesium and Alloys 2024年第3期12卷 1239-1256页

作者： Jeongho Yang Woongbeom Heogh Hogi Ju Sukhyun Kang Tae-Sik Jang Hyun-Do Jung Mohammad Jahazi Seung chul Han Seong Je park Hyoung Seop Kim Susmita Bose Amit Bandyopadhyay Martin Byung-Guk Jun Young Won Kim Dae-kyeom Kim Rigoberto CAdvincula Clodualdo Aranas Jr Sang Hoon Kim School of Mechanical Engineering Pusan National UniversityBusan 46241Republic of Korea Department of Mechanical Design Engineering Hanyang UniversitySeoul 04763Republic of Korea Process Research 3 Team LG Display Co.Ltd.PajuGyeonggi-do 10845Republic of Korea Department of Materials Science and Engineering Chosun UniversityGwangju 61452Republic of Korea Institute of Well-Aging Medicare&Chosun University LAMP Center Chosun UniversityGwangju 61452Republic of Korea Division of Materials Science and Engineering Hanyang UniversitySeoul 04763Republic of Korea Department of Mechanical Engineering École de Technologie SupérieureMontrealQuebec H3C 1K3Canada Material&Component Convergence R&D Center Korea Construction Equipment Technology InstituteGunsanJeollabuk-do 54002Republic of Korea School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore Graduate Institute of Ferrous&Eco Materials Technology Pohang University of Science and TechnologyPohangGyeongsangbuk-do 37673Republic of Korea Advanced Institute for Materials Research Tohoku UniversitySendai 980-8577Japan Institute for Convergence Research and Education in Advanced Technology Yonsei UniversitySeoul 03722Republic of Korea School of Mechanical and Materials Engineering Washington State UniversityPullmanWashington 99164USA School of Mechanical Engineering Purdue UniversityWest LafayetteIndiana 47907USA Research Institute of Advanced Manufacturing Technology Korea Institute of Industrial TechnologyIncheon 21999Republic of Korea Department of Macromolecular Science and Engineering Case Western Reserve UniversityClevelandOhio 44106USA Department of Chemical and Biomolecular Engineering and Joint Institute for Advanced Materials University of TennesseeKnoxvilleTennessee 37996USA Center for Nanophase Materials and Sciences Oak Ridge National LaboratoryOak RidgeTennessee 37830USA Department of Mechanical Engineering University of New BrunswickFrederictonNew Brunswick E3B 5A3Cana

The ex-situ incorporation of the secondary SiC reinforcement,along with the in-situ incorporation of the tertiary and quaternary Mg_(3)N_(2) and Si_(3)N_(4) phases,in the primary matrix of Mg_(2)Si is employed in order to provide ultimate wear resistance based on the laser-irradiation-induced inclusion of N_(2) gas during laser powder bed *** is substantialized based on both the thermal diffusion-and chemical reactionbased metallurgy of the Mg_(2)Si–SiC/nitride hybrid *** study also proposes a functional platform for systematically modulating a functionally graded structure and modeling build-direction-dependent architectonics during additive *** strategy enables the development of a compositional gradient from the center to the edge of each melt pool of the Mg_(2)Si–SiC/nitride hybrid ***,the coefficient of friction of the hybrid composite exhibits a 309.3%decrease to–1.67 compared to–0.54 for the conventional nonreinforced Mg_(2)Si structure,while the tensile strength exhibits a 171.3%increase to 831.5 MPa compared to 485.3 MPa for the conventional *** outstanding mechanical behavior is due to the(1)the complementary and synergistic reinforcement effects of the SiC and nitride compounds,each of which possesses an intrinsically high hardness,and(2)the strong adhesion of these compounds to the Mg_(2)Si matrix despite their small sizes and low concentrations.

关键词： Laser powder bed fusion Mg_(2)Si-SiC/nitride hybrid composite Both the thermal diffusion-and chemical reaction-based metallurgy Functionally graded structure Compositional gradient Wear resistance.