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2023: Weather and Climate Extremes Hitting the Globe with Emerging Features
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作者 Wenxia ZHANG Robin CLARK +12 位作者 Tianjun ZHOU Laurent LI Chao LI Juan RIVERA Lixia ZHANG Kexin GUI Tingyu ZHANG Lan LI Rongyun PAN Yongjun CHEN Shijie TANG Xin HUANG Shuai HU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1001-1016,共16页
Globally,2023 was the warmest observed year on record since at least 1850 and,according to proxy evidence,possibly of the past 100000 years.As in recent years,the record warmth has again been accompanied with yet more... Globally,2023 was the warmest observed year on record since at least 1850 and,according to proxy evidence,possibly of the past 100000 years.As in recent years,the record warmth has again been accompanied with yet more extreme weather and climate events throughout the world.Here,we provide an overview of those of 2023,with details and key background causes to help build upon our understanding of the roles of internal climate variability and anthropogenic climate change.We also highlight emerging features associated with some of these extreme events.Hot extremes are occurring earlier in the year,and increasingly simultaneously in differing parts of the world(e.g.,the concurrent hot extremes in the Northern Hemisphere in July 2023).Intense cyclones are exacerbating precipitation extremes(e.g.,the North China flooding in July and the Libya flooding in September).Droughts in some regions(e.g.,California and the Horn of Africa)have transitioned into flood conditions.Climate extremes also show increasing interactions with ecosystems via wildfires(e.g.,those in Hawaii in August and in Canada from spring to autumn 2023)and sandstorms(e.g.,those in Mongolia in April 2023).Finally,we also consider the challenges to research that these emerging characteristics present for the strategy and practice of adaptation. 展开更多
关键词 weather and climate extremes temperature extremes extreme precipitation DROUGHT WILDFIRES
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Achievements and challenges of primate conservation in China 被引量:1
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作者 Bao-Guo Li He Zhang +21 位作者 Ming Li Xue-Long Jiang Peng-Fei Fan Jiang Zhou Song-Tao Guo Xiao-Guang Qi Jin-Hua Li Ji-Qi Lu Dong-Po Xia Liang-Wei Cui Zuo-Fu Xiang Qi-Hai Zhou Zhi-Pang Huang Cheng-Ming Huang Wen Xiao Hui-Jian Hu Zhi-Xin Zhou Ming-Yong Chen Da-Yong Li Peng-Lai Fan Yin Yang Ru-Liang Pan 《Zoological Research(Diversity and Conservation)》 2024年第1期66-74,共9页
The dual impact of climate change and human activities has precipitated a sharp decline in primate biodiversity globally.China is home to the most diverse primate species in the Northern hemisphere,which face severe e... The dual impact of climate change and human activities has precipitated a sharp decline in primate biodiversity globally.China is home to the most diverse primate species in the Northern hemisphere,which face severe ecological threats due to the expansion of modern agriculture,extensive exploitation and consumption of natural resources,and excessive land development during its transition from an agricultural to a modern society.In response,China has implemented various ecological conservation measures,including habitat restoration and protection.These efforts have made substantial strides in biodiversity conservation,with certain regions witnessing an increase in primate populations.In the current study,we conducted a systematic review of historical documents and field research data related to Chinese primates,evaluating the endangered status of primate species in China.Despite improvements in the habitats of most primate species and some population growth,many species still face severe threats,including declining and small populations.Species such as the Myanmar snub-nosed monkey(Rhinopithecus strykeri),eastern black crested gibbon(Nomascus nasutus),and Hainan gibbon(N.hainanus)remain particularly vulnerable due to their limited distribution ranges and extremely small populations.Insufficient scientific data,fragmented information,and not enough studies in conservation biology further compound the challenges.Moreover,there is a notable lack of detailed population monitoring data for species such as the Bengal slow loris(Nycticebus bengalensis),pygmy slow loris(N.pygmaeus),Indochinese gray langur(Trachypithecus crepusculus),Shortridge’s langur(T.shortridgei),and capped langur(T.pileatus),which hinders the development of practical and targeted conservation management strategies.Therefore,for national biodiversity conservation,there is an urgent need for specialized primate surveys,enhancing habitat protection and restoration,and increasing focus on cross-border conservation strategies and regional cooperation.There is also a need to establish a comprehensive and systematic research database platform,conduct continuous and in-depth research in primate biology,and actively engage in the scientific assessment of ecotourism.Additionally,strengthening public awareness and education on wildlife conservation remains essential.Such integrated and systematic efforts will provide scientific support for the current and future conservation and management of primate species in China. 展开更多
关键词 PRIMATES BIODIVERSITY Habitat fragmentation Habitat restoration Conservation strategies
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Characteristics of cross transmission of gut fungal pathogens between wintering Hooded Cranes and sympatric Domestic Geese
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作者 Yuannuo Wu Xiaoyu Fan +3 位作者 Jie Yu Tianci Liu Rong Cui Xingjia Xiang 《Avian Research》 SCIE CSCD 2023年第4期640-646,共7页
Migratory birds travel long distance and link various pathogens.Due to habitat degradation,wintering waterfowls forage together with poultry,increasing the risk of pathogen transmission between hosts.We investigated t... Migratory birds travel long distance and link various pathogens.Due to habitat degradation,wintering waterfowls forage together with poultry,increasing the risk of pathogen transmission between hosts.We investigated the fungal communities between wintering Hooded Cranes and Domestic Geese by high-throughput sequencing,and inferred the potential gut pathogens for both hosts at different wintering stages.The fungal community compositions were significantly different between seasons and between the hosts.The negative correlation was found between fungal diversity and pathogenic diversity,with higher fungal diversity and less pathogenic diversity in early stage and less fungal diversity and higher pathogenic diversity in late stage for both hosts.The dissimilarity of pathogenic community compositions decreased from early to late stage,with the quantity of overlapping potential pathogenic OTUs increasing along wintering periods between the two hosts,demonstrating the existence of pathogen cross transmission between the two hosts.Furthermore,the transmission pathway of avian pathogens was mainly from Hooded Cranes to Domestic Geese while the transmission direction of human pathogens was primarily from Domestic Geese to wild cranes.Based on above results,we argued that pathogen cross transmission and underlying outbreak risk of disease should be closely monitored in migratory birds and domestic poultry. 展开更多
关键词 Cross transmission Fungi Gut pathogen Migratory bird Poultry
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铜颗粒低温烧结技术的研究进展 被引量:4
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作者 李俊龙 徐杨 +2 位作者 赵雪龙 王英辉 Tadatomo Suga 《焊接学报》 EI CAS CSCD 北大核心 2022年第3期13-24,I0003,I0004,共14页
金属纳米材料因具有良好的导电导热性以及能够在较低温度下进行烧结,是功率器件在高温高压高频等工作环境下服役所需的关键电子封装材料之一.文中对应用于功率器件封装领域的铜颗粒实现烧结的研究进行了综述,阐明了目前通过铜颗粒烧结... 金属纳米材料因具有良好的导电导热性以及能够在较低温度下进行烧结,是功率器件在高温高压高频等工作环境下服役所需的关键电子封装材料之一.文中对应用于功率器件封装领域的铜颗粒实现烧结的研究进行了综述,阐明了目前通过铜颗粒烧结技术实现低温键合的研发背景.从铜颗粒烧结材料的制备、工艺参数和还原方法等关键影响因素出发,讨论、归纳了基于不同烧结机理的低温烧结铜颗粒材料接头的力学性能和电学性能.此外,介绍了铜颗粒烧结技术在贴片封装和全铜互连领域中应用的优良特性.通过对该领域研究成果的分析,结果表明,目前铜烧结材料仍然受到氧化问题的挑战,需要进一步在接头性能的精准调控方面深入研究. 展开更多
关键词 烧结 Cu颗粒 低温键合 全铜互连 功率器件
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Recycle for Sludge Scrap of Nd-Fe-B Sintered Magnet as Isotropic Bonded Magnet 被引量:4
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作者 Masahiro Itoh Masahiro Masuda +1 位作者 Shunji Suzuki Ken-ichi Machida 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第1期168-171,共4页
The reduction diffusion method was performed for the sludge scrap of Nd-Fe-B sintered magnets with adding Ca metal to recover the oxidized Nd-Fe-B phase. After washing the resultant powders to remove Ca metal componen... The reduction diffusion method was performed for the sludge scrap of Nd-Fe-B sintered magnets with adding Ca metal to recover the oxidized Nd-Fe-B phase. After washing the resultant powders to remove Ca metal component, the powders obtained were recycled as an isotropic magnetic powder by the melt spinning method. The magnetic properties of powders as recycled were inferior, especially for the coercivity value, due to the deletion of rare earth metals during the washing process. The adjustment of metal composition, i.e., the addition of Nd metal, at the melt spinning process improved the magnetic properties to be B r=~0.75 T, H cj=~0.93 mA·m -1, and (BH) max=~91 kJ·m -3. The magnetic properties of the bonded magnets prepared from the composition-adjusted powders were B r=~0.66 T, H cj=~0.92 mA·m -1, and (BH) max=~70 kJ·m -3, which are approximately comparable to the commercially available MQPB boned one (B r=~0.73 T, H cj=~0.79 mA·m -1, and (BH) max=~86 kJ·m -3). 展开更多
关键词 Nd-Fe-B sintered magnet recycling isotropic Nd-Fe-B bonded magnet melt-spinning method sludge scrap rare earths
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Platelet thromboxane(11-dehydro-Thromboxane B_2) and aspirin response in patients with diabetes and coronary artery disease 被引量:13
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作者 Luis R Lopez Kirk E Guyer +3 位作者 Ignacio Garcia De La Torre Kelly R Pitts Eiji Matsuura Paul RJ Ames 《World Journal of Diabetes》 SCIE CAS 2014年第2期115-127,共13页
Aspirin(ASA) irreversibly inhibits platelet cyclooxygenase-1(COX-1) leading to decreased thromboxane-mediated platelet activation. The effect of ASA ingestion on thromboxane generation was evaluated in patients with d... Aspirin(ASA) irreversibly inhibits platelet cyclooxygenase-1(COX-1) leading to decreased thromboxane-mediated platelet activation. The effect of ASA ingestion on thromboxane generation was evaluated in patients with diabetes(DM) and cardiovascular disease. Thromboxane inhibition was assessed by measuring the urinary excretion of 11-dehydro-thromboxane B2(11dhTxB2), a stable metabolite of thromboxane A2. The mean baseline urinary 11dhTxB2 of DM was 69.6% higher than healthy controls(P = 0.024): female subjects(DM and controls) had 50.9% higher baseline 11dhTxB2 than males(P = 0.0004), while age or disease duration had no influence. Daily ASA ingestion inhibited urinary 11dhTxB2 in both DM(71.7%) and controls(75.1%, P < 0.0001). Using a pre-established cut-off of 1500 pg/mg of urinary 11dhTxB2, there were twice as many ASA poor responders(ASA "resistant") in DM than in controls(14.8% and 8.4%, respectively). The rate of ASA poor responders in two populations of acute coronary syndrome(ACS) patients was 28.6 and 28.7%, in spite of a significant(81.6%) inhibition of urinary 11dhTxB2(P < 0.0001). Both baseline 11dhTxB2 levels and rate of poor ASA responders were significantly higher in DM and ACS compared to controls. Underlying systemic oxidative inflammation may maintain platelet function in atherosclerotic cardiovascular disease irrespective of COX-1 pathway inhibition and/or increase systemic generation of thromboxane from non-platelet sources. 展开更多
关键词 DIABETES Cardiovascular disease PLATELETS THROMBOXANE ASPIRIN
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Recent Progress on Metal–Organic Framework and Its Derivatives as Novel Fire Retardants to Polymeric Materials 被引量:7
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作者 Jing Zhang Zhi Li +1 位作者 Xiao‑Lin Qi De‑Yi Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2020年第12期173-193,共21页
High flammability of polymers has become a major issue which has restricted its applications.Recently,highly crystalline materials and metal–organic frameworks(MOFs),which consisted of metal ions and organic linkers,... High flammability of polymers has become a major issue which has restricted its applications.Recently,highly crystalline materials and metal–organic frameworks(MOFs),which consisted of metal ions and organic linkers,have been intensively employed as novel fire retardants(FRs)for a variety of polymers(MOF/polymer).The MOFs possessed abundant transition metal species,fire-retardant elements and potential carbon source accompanied with the facile tuning of the structure and property,making MOF,its derivatives and MOF hybrids promising for fire retardancy research.The recent progress and strategies to prepare MOF-based FRs are emphasized and summarized.The fire retardancy mechanisms of MOF/polymer composites are explained,which may guide the future design for efficient MOF-based FRs.Finally,the challenges and prospects related to different MOFbased FRs are also discussed and aim to provide a fast and holistic overview,which is beneficial for researchers to quickly get up to speed with the latest development in this field. 展开更多
关键词 Metal–organic frameworks HYBRIDS POLYMERS COMPOSITES Fire retardancy
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Exploration of the enhanced performances for silk fibroin/sodium alginate composite coatings on biodegradable Mg-Zn-Ca alloy 被引量:3
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作者 Hui Fang Chenxi Wang +3 位作者 Shicheng Zhou Ge Li Yanhong Tian Tadatomo Suga 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2021年第5期1594-1610,共17页
To expand the future clinic applications of biodegradable magnesium alloy,polymer coatings with excellent biocompatibility are the keys to solve the local alkalinity and rapid hydrogen release.Natural-organic silk fib... To expand the future clinic applications of biodegradable magnesium alloy,polymer coatings with excellent biocompatibility are the keys to solve the local alkalinity and rapid hydrogen release.Natural-organic silk fibroin provides an approach to fabricate a protective coating on biomedical Mg-Zn-Ca alloy,however,the adhesion force and mechanical properties of the coating on substrates are ought to be further improved without any chemical conversion/intermediate layer.Hereby,based on VUV/O;surface activation,a hybrid of silk fibroin and sodium alginate is proposed to enhance the adhesion force and mechanical properties of the composite coatings on hydrophilic Mg-Zn-Ca alloy surfaces.Various mass ratios of sodium alginate addition were investigated to achieve the optimum coating strategy.The nanoscratch test and nanoindentation test confirmed that the adhesion force was tripled and mechanical properties index was significantly improved when the mass ratio of silk fibroin/sodium alginate was 70/30 compared to pure silk fibroin or sodium alginate coatings.Meanwhile,the corrosion rate of the coated Mg-Zn-Ca alloy was significantly delayed with the addition of sodium alginate,resulting in a reaction layer during corrosion process.Furthermore,the mechanisms for both adhesion and corrosion processes were discussed in detail.Our findings offer more possibilities for the controllable surface performance of degradable metals. 展开更多
关键词 Mg-Zn-Ca alloy Silk fibroin Sodium alginate Adhesion force Mechanical property Corrosion resistance
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Molecular and morphological evidence for a new species of the genus Typhlomys(Rodentia:Platacanthomyidae) 被引量:4
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作者 Ting-Li Hu Feng Cheng +6 位作者 Zhen Xu Zhong-Zheng Chen Lei Yu Qian Ban Chun-Lin Li Tao Pan Bao-Wei Zhang 《Zoological Research》 SCIE CAS CSCD 2021年第1期100-107,共8页
DEAR EDITOR,In this study,we reassessed the taxonomic position of Typhlomys(Rodentia:Platacanthomyidae)from Huangshan,Anhui,China,based on morphological and molecular evidence.Results suggested that Typhlomys is compr... DEAR EDITOR,In this study,we reassessed the taxonomic position of Typhlomys(Rodentia:Platacanthomyidae)from Huangshan,Anhui,China,based on morphological and molecular evidence.Results suggested that Typhlomys is comprised of up to six species,including four currently recognized species(Typhlomys cinereus,T.chapensis,T.daloushanensis,and T.nanus),one unconfirmed candidate species,and one new species(Typhlomys huangshanensis sp.nov.).Morphological analyses further supported the designation of the Huangshan specimens found at mid-elevations in the southern Huangshan Mountains(600 m to 1200 m a.s.l.)as a new species. 展开更多
关键词 ANHUI species. MORPHOLOGICAL
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Viral hepatitis and human immunodeficiency virus coinfections in Asia 被引量:2
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作者 Takako Utsumi Maria I Lusida 《World Journal of Virology》 2015年第2期96-104,共9页
Hepatitis B virus(HBV), hepatitis C virus(HCV),and human immunodeficiency virus(HIV) affect many people in Asian countries, although there are geographic differences. Both HBV and HIV(HBV/HIV) and HCV/HIV co-infection... Hepatitis B virus(HBV), hepatitis C virus(HCV),and human immunodeficiency virus(HIV) affect many people in Asian countries, although there are geographic differences. Both HBV and HIV(HBV/HIV) and HCV/HIV co-infections are highly prevalent in Asia. Hetero- and homosexual, injection drug use, and geographic area are strong predictors of HBV, HCV, and HIV serostatus. In HBV endemic regions, the prevalence and genotype distribution of HBV/HIV coinfection is almost comparable with that in the general population. In Japan, where HBV has low endemicity, the prevalence of HBV/HIV co-infection is approximately 10-fold higher than that in the general population, and HBV Ae is the most common subgenotype among HIV infected individuals. Highly active antiretroviral therapy(HAART) is an effective treatment for HIV/Acquired Immune Deficiency Syndrome. Lamivudine, a component of HAART, is an effective treatment for HBV, HIV, and HBV/HIV co-infection; however, cost, emerging drug resistance, antiretroviral-associated liver toxicity and liver-related morbidity due to HCV progression are particular concerns. HCV/HIV co-infection may accelerate the clinical progression of both HCV and HIV. The high prevalence of HBV/HIV and HCV/HIV co-infections in Asia underscores the need to improve prevention and control measures, as fewer evidencebased prevention strategies are available(compared with Western countries). In this review, the most recent publications on the prevalence of HBV/HIV and HCV/HIV co-infections and related issues, such as therapy and problems in Asia, are updated and summarized. 展开更多
关键词 HEPATITIS B VIRUS HEPATITIS C VIRUS COINFECTION Human IMMUNODEFICIENCY VIRUS Prevalence ASIA Pathogenicity Natural history Problems Drug resistance
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Molecular epidemiology of hepatitis B virus in Asia 被引量:1
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作者 Takako Utsumi Yoshihiko Yano Hak Hotta 《World Journal of Medical Genetics》 2014年第2期19-26,共8页
Although safe and effective vaccines against hepatitis B virus(HBV) have been available for three decades, HBV infection remains the leading cause of chronic hepatitis, cirrhosis and hepatocellular carcinoma(HCC) worl... Although safe and effective vaccines against hepatitis B virus(HBV) have been available for three decades, HBV infection remains the leading cause of chronic hepatitis, cirrhosis and hepatocellular carcinoma(HCC) worldwide, especially in Asian countries. HBV has been classified into at least 9 genotypes according to the molecular evolutionary analysis of the genomic DNA sequence and shown to have a distinct geographical distribution. Novel HBV genotypes/subgenotypes have been reported, especially from Southeast Asian countries. The clinical characteristics and therapeutic effectiveness of interferon(IFN) and nucleos(t)ide analogues vary among different HBV genotypes. Mutations at T1653 C in subgenotype C2 from Japan and South Korea, C/A1753 T and C1858 T in subgenotype C1 from Vietnam, and C1638 T and T1753 V in subgenotype B3 from Indonesia were reported to be associated with advanced liver diseases including HCC. Genotype distribution in Japan has been changed by an increasing ratio of subgenotype A2 in chronic hepatitis B. While a large number of epidemiological and clinical studies have been reported from Asian countries, most of the studies were conducted in developed countries such as Taiwan, China, South Korea and Japan. In this review, the most recent publications on the geographical distribution of genetic variants of HBV and related issues such as disease progression and therapy in Asia are updated and summarized. 展开更多
关键词 Hepatitis B virus GENOTYPE SUBGENOTYPE Molecular epidemiology ASIA PATHOGENICITY Drug resistance
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Prevalence and genotype distribution of hepatitis B virus among migrant workers in Lombok Island, Indonesia 被引量:1
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作者 Laura Navika Yamani Eva Triani +8 位作者 Mochamad Amin Juniastuti Takako Utsumi Soetjipto Nasronudin Yoshihiko Yano Hak Hotta Yoshitake Hayashi Maria Inge Lusida 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2020年第1期8-16,共9页
Objective:To examine the potential risk of hepatitis B virus(HBV)spread in Indonesia by migrant workers,based on the molecular characteristics of HBV strains.Methods:Sera collected from migrant workers traveling to th... Objective:To examine the potential risk of hepatitis B virus(HBV)spread in Indonesia by migrant workers,based on the molecular characteristics of HBV strains.Methods:Sera collected from migrant workers traveling to their destination countries(pre-migrant workers)and those returning to Indonesia(post-migrant workers)were screened for HBsAg by ELISA,followed by HBV DNA detection by PCR and(sub)genotype/subtype determination according to surface region and whole genome sequencing.Results:Of 87 pre-migrant workers,15(17.24%)were HBsAgpositive,whereas 15(12.10%)of 124 post-migrant workers were HBs Ag seropositive.HBV genotype analysis based on the S region showed that HBV-B3/adw2 was predominant(96.15%,25/26)whereas 3.85%(1/26)of isolates were HBV-C3/adrq+.Whole genome sequencing of selected strains and phylogenetic tree analysis identified subgenotype B7 in three samples previously categorized as subgenotype B3 based on S region analysis,supporting a recent argument that subgenotypes B5/B7/B8/B9 could be considered as a quasi-subgenotype of B3.Conclusions:A high prevalence of HBsAg carriers was detected among migrant workers from Lombok Island,with no significant difference in prevalence between before and after returning to Indonesia.All strains were classified into genotypes common in Indonesia,and the results suggested that migrant workers are not a risk factor for HBV transmission into Indonesia. 展开更多
关键词 HBV Subgenotypes MIGRANT workers Indonesia
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Immunometabolism and potential targets in severe COVID-19 peripheral immune responses 被引量:1
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作者 Shanshan Wang Xian Zeng +5 位作者 Yali Wang Yuzong Chen Chaoxin Wang Dongzhi Zhuoma Fengying Zhang Yufen Zhao 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2021年第6期665-667,共3页
In a recent single cell transcriptomic investigation of the peripheral immune responses of the patients with severe COVID-19[1],no substantial expression of pro-inflammatory cytokines has been identified in the periph... In a recent single cell transcriptomic investigation of the peripheral immune responses of the patients with severe COVID-19[1],no substantial expression of pro-inflammatory cytokines has been identified in the peripheral monocytes and lymphocytes,while these peripheral immune cells exhibit phenotypes of heterogeneously expressed interferon-stimulated genes in certain COVID-19 patients.These genes may contribute to the inhibitory response to the viral entry,translation,replication and egress.Questions remain regarding why the peripheral cytokine production is constrained,what additional roles these peripheral immune cells may play in COVID-19 pathophysiology,and which potential targets can be explored for facilitating COVID-19 therapeutics. 展开更多
关键词 METABOLISM INTERFERON LYMPHOCYTES
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Magnetic Properties of Nd-Fe-B Sintered Magnet Powders Recovered by Yb Metal Vapor Sorption
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作者 Horikawa T Itoh M +1 位作者 Suzuki Shunji Machida K 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第1期152-156,共5页
Fine ground powders of Nd-Fe-B sintered magnet bulks (particle size=46~125 μm in diameter) were coated and alloyed with Yb metal by sorbing them. A significant recovery of the decreased magnetic properties of the gr... Fine ground powders of Nd-Fe-B sintered magnet bulks (particle size=46~125 μm in diameter) were coated and alloyed with Yb metal by sorbing them. A significant recovery of the decreased magnetic properties of the ground powders (remanence B r=~0.95 T, coercivity H cj =~227 kA·m -1 and maximum energy product (BH) max=~48 8 kJ·m -3) was observed in accordance with increasing temperature up to 800 ℃. The sorbing temperature and time for Yb metal vapor were optimized and after heating at 800 ℃ for 90 min and annealing subsequently at 610 ℃ for 60 min, the B r, H cj and (BH) max values were increased to be 0.98 T, 712 kA·m -1 and 173 kJ·m -3, respectively. From the microstructural characterizations of resulting samples by using X-ray diffraction (XRD), scanning electron microscopy (SEM), and electron probe X-ray microanalyzer (EPMA), it is found that the sorbed Yb metal uniformly covers the surface and diffuses to the Nd-rich grain boundary of fine ground powders of Nd-Fe-B sintered magnet bulks forming a (Nd,Yb)Fe 2 phase. 展开更多
关键词 metal materials Nd 2Fe 14B sintered magnets metal vapor sorption magnetic properties recovery rare earths
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Microwave Behavior of α-Fe/Fe_3B/Y_2O_3 Nanocomposites in GHz Range Prepared by Melt-Spun Technique
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作者 Masahiro Itoh Ken-ichi Machida 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第1期13-16,共4页
Nanocomposites α-Fe/Fe 3B/Y 2O 3 were prepared by a melt-spun technique, and the electromagnetic wave absorption properties were measured in the 0 05~20 05 GHz range. Compared with α-Fe/Y 2O 3 composites, th... Nanocomposites α-Fe/Fe 3B/Y 2O 3 were prepared by a melt-spun technique, and the electromagnetic wave absorption properties were measured in the 0 05~20 05 GHz range. Compared with α-Fe/Y 2O 3 composites, the resonance frequency (f r) of α-Fe/Fe 3B/Y 2O 3 shifted to a higher frequency range due to the large anisotropy field (H A) of tetragonal Fe 3B (~0 4 mA·m -1). The relative permittivity (ε r=ε r′-jε r″) was constantly low over the 0 5~10 GHz region, which indicates that the composite powders have a high resistivity (ρ=~100 Ωm). The effective electromagnetic wave absorption (RL<-20 dB) was obtained in a frequency range of 2.7~6.5 GHz on resin composites of 80% (mass fraction) α-Fe/Fe 3B/Y 2O 3 powders, with thickness of 6~3 mm respectively. A minimum reflection loss of -33 dB was observed at 4.5 GHz with an absorber thickness of 4 mm. 展开更多
关键词 MELT-SPUN NANOCOMPOSITES electromagnetic wave absorption anisotropy field matching frequency
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A Novel Stacked Array Antenna with Uni-planar Compact EBG Reflector
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作者 Peng Chen Chaoyang Chen +1 位作者 Xiaodong Yang Xiaoming Zhu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第1期59-62,共4页
Most broadband microstrip antennae are implemented in the form of slot structure or laminate structure,which provide a broad impedance bandwidth and meanwhile bring large sidelobes and backlobes. A novel uni-planar co... Most broadband microstrip antennae are implemented in the form of slot structure or laminate structure,which provide a broad impedance bandwidth and meanwhile bring large sidelobes and backlobes. A novel uni-planar compact electromagnetic band-gap( EBG) structure is proposed, which shows excellent performance when applied to broadband stacked or aperture coupled microstrip array antennae. The test results indicate that,the directivity is effectively improved,and the front-to-back ratio is increased,and the thickness of the antenna is reduced. These improvements make this structure better used in airborne antennae. 展开更多
关键词 EBG UC-EBG MICROSTRIP array antenna stacked MICROS
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Psychological distress in elderly cancer patients
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作者 Jing-Fang Hong Wei Zhang +2 位作者 Yong-Xia Song Lun-Fang Xie Wei-Li Wang 《International Journal of Nursing Sciences》 2015年第1期23-27,共5页
Objective:To investigate the prevalence and specific manifestations of psychological distress in elderly cancer patients.Methods:In this cross-sectional study,153 elderly patients with cancer admitted to two tertiary ... Objective:To investigate the prevalence and specific manifestations of psychological distress in elderly cancer patients.Methods:In this cross-sectional study,153 elderly patients with cancer admitted to two tertiary hospitals were investigated using the convenience sampling method.Distress thermometer and the problem list,recommended by the National Comprehensive Cancer Network,were used to assess the psychological distress and its specific manifestations.A self-designed questionnaire was used to collect demographic data.Results:A total of 67 participants(43.8%)exhibited psychological distress to some degree.The analysis of the sub-categories in the problem list showed significant differences(p<0.001).The highest scoring category was the emotional problems,followed by practical problems,physiological problems,and family problems.Among 34 items included in the statistical analysis,the top five were worry(73.9%),depression(55.6%),pain(54.2%),economic problems(52.3%),and fear(49.7%).Married participants,those with higher education and higher monthly income had significantly lower psychological distress score compared with single patients,those with lower education,and lower monthly income(p<0.05).Conclusions:Psychological distress is prevalent among elderly patients with cancer and,therefore,should be considered by the health professionals treating these patients. 展开更多
关键词 Aged CANCER Cross-sectional studies Problem list Psychological distress
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Tunable inhibition ofβ-amyloid peptides by fast green molecules
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作者 杨甜甜 俞天翔 +1 位作者 赵文辉 林冬冬 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第8期543-550,共8页
The aggregation ofβ-amyloid(Aβ)protein into toxic intermediates and mature fibrils is considered to be one of the main causes of Alzheimer's disease(AD).Small molecules as one of blockers are expected to be the ... The aggregation ofβ-amyloid(Aβ)protein into toxic intermediates and mature fibrils is considered to be one of the main causes of Alzheimer's disease(AD).Small molecules as one of blockers are expected to be the potential drug treatment for the disease.However,the nucleation process in molecular assembly is less informative in the literatures.In this work,the formation of Aβ(16-22)peptides was investigated with the presence of small molecule of fast green(FG)at the initial aggregation stage.The results exhibited the tunable inhibitory ability of FG molecules on Aβ(16-22)peptides.Atomic force microscopy(AFM)demonstrated that the inhibitory effect would be dependent on the dose of FG molecules,which could delay the lag time(nucleation)and form single layer conjugates.Spectral measurements further showed that theβ-sheet secondary structure of Aβ(16-22)reduced dramatically after the presence of FG molecules.Instead,non-β-sheet nanosheets were formed when the FG/Aβ(16-22)ratio reached 1:1.In addition,the cytotoxicity of aggregates reduced greatly with the presence of FG molecules compared with the Aβ(16-22)fibrils.Overall,this study provided a method for suppressing the toxic amyloid aggregates by FG molecules efficiently,and also showed a strategy for fabrication of two-dimensional materials by small molecules. 展开更多
关键词 AMYLOID fast green AGGREGATION Alzheimer's disease
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Metabolism regulation of TD26 in hepatocellular carcinoma: mechanistic links and potential clinical implication
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作者 Chenchen Wang Jie Cai +2 位作者 Hailong Wu Xiaoni Kong Qiang Xia 《Cancer Biology & Medicine》 SCIE CAS CSCD 2018年第S01期15-16,共2页
Objective:Hepatocellular carcinoma(HCC)is a leading cause of cancer-related deaths worldwide,and HCC cells metabolically distinct from normal hepatocytes.Increased lipogenesis has been reported to play a critical role... Objective:Hepatocellular carcinoma(HCC)is a leading cause of cancer-related deaths worldwide,and HCC cells metabolically distinct from normal hepatocytes.Increased lipogenesis has been reported to play a critical role in HCC progression.This study aims to investigate the underlying mechanism contributing to lipogenesis increase in HCC. 展开更多
关键词 METABOLISM REGULATION IMPLICATION
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二垩英与资源回收-Ⅱ燃烧过程二垩英抑制和生成基础研究
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作者 Hirotoshi KAWABATA Tateo USUI Shigeta HARA Toshihiro TANAKA Hideki ONO-NAKAZATO Mashayuki TANABE Katsukiyo MARUKAWA 《钢铁》 CAS CSCD 北大核心 2003年第z1期76-78,共3页
氯来源、种类和燃烧物中氯浓度对燃烧过程中二垩英生成有重要影响.在实验燃烧炉中研究1 073K温度下上述三种因素对燃烧过程二垩英生成的影响.二垩英生成浓度在相同氯源和种类条件下与燃烧物中氯含量几乎成正比,且受氯源明显影响.如有机... 氯来源、种类和燃烧物中氯浓度对燃烧过程中二垩英生成有重要影响.在实验燃烧炉中研究1 073K温度下上述三种因素对燃烧过程二垩英生成的影响.二垩英生成浓度在相同氯源和种类条件下与燃烧物中氯含量几乎成正比,且受氯源明显影响.如有机氯化合物或无机氯化物.即使对无机氯化物,在有活性氯存在时也会生成高浓度二垩英,如由盐和面粉形成的水化物中的活性氯. 展开更多
关键词 氯源 氯种类 燃烧过程 二垩英/呋喃 水化物 PVC
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