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国际制图协会(ICA)第21届国际制图研讨会和第12届代表大会 被引量:5
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作者 本刊编辑部 李莉 +4 位作者 廖克 张清浦 陈毓芬 孙群 陈成永 《地图》 北大核心 2003年第6期5-17,共13页
国际制图协会(International Cartographic Association,简称ICA,亦译国际地图学协会)是世界地图制图学界权威的学术组织,其宗旨是促进国际间地图制图学的发展,加强国际间技术合作和技术交流。它的任务是推进地图制图学的研究,鼓励和协... 国际制图协会(International Cartographic Association,简称ICA,亦译国际地图学协会)是世界地图制图学界权威的学术组织,其宗旨是促进国际间地图制图学的发展,加强国际间技术合作和技术交流。它的任务是推进地图制图学的研究,鼓励和协调这一领域的科研活动,包括国际间的协作、技术和文献的交流,促进地图制图学教育的发展,推动地图制图学的科普工作,组织地图制图学的国际学术讨论会、讲座、培训和技术展览会等,并参加其他国际学术组织的有关会议和活动。中国测绘学会于1980年加入了ICA,现为四级会员。中国积极参加并主办ICA的各项活动,在ICA中发挥了积极的作用与影响。武汉大学胡毓钜先生曾担任两届ICA副主席、国家基础地理信息中心李莉女士于1999年当选为ICA副主席。国家测绘局和中国测绘学会2001年8月在北京成功举办第20届国际制图大会,在国际制图界造成了空前的影响。 展开更多
关键词 国际制图协会 ICA 地图制图学 测绘学
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Etiological and Evolutionary Profile of the Child’s Pericarditis in Tropical Environments
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作者 Richard Azagoh-Kouadio Jacob Slanziahuelie Enoh +5 位作者 Jean-Jacques Yao Atteby Line Guei Couitchere Lassina Cisse Yves N’da Kouakou N’goran Kouadio Euloge Kramoh Oulai Soumahoro 《Open Journal of Pediatrics》 2017年第3期164-177,共14页
Background: Liquid pericarditis is a frequent cause of hospitalization in developing countries. Objective: of this study was to describe the etiological and evolutionary aspects of fluid pericarditis in pediatric card... Background: Liquid pericarditis is a frequent cause of hospitalization in developing countries. Objective: of this study was to describe the etiological and evolutionary aspects of fluid pericarditis in pediatric cardiology at ICA. Methods: This was a retrospective study of 42 cases of fluid pericarditis diagnosed among 202 children hospitalized over a five-year period (1st January 2009 to 31st December 2014). All patients with pericardial effusion were included in the study. Results: Prevalence was estimated at 20.8% of hospitalizations, sex ratio was 1.1 with a female predominance (52%) and the mean age at 9.2 years (11 days to 15 years). The etiologic varieties identified were: tuberculosis 22 cases, 52%, rheumatic pericarditis 6 cases or 14.3%, chronic parietal endocarditis 5 cases (11.9%), bacterial pericarditis with trivial germ 3 cases (7.1% 3 cases (7.1%), post-surgery syndrome 2 cases (4.8%), umbilical post-catheterization 1 case (2.4%). HIV serology was positive in 11.9% of cases. The progression was favorable in 55% of the cases with 10% of deaths. Conclusion: Fluid pericarditis in children is a severe condition that is clearly on the rise today, especially in immunocompromised patients. Optimal management of fluid pericarditis in children is the best guarantee to avoid short-term tamponade and in the medium term constriction. 展开更多
关键词 PERICARDITIS ETIOLOGY EVOLUTION CHILDREN Tropical Diseases
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传播学转型:趋势、理论与方法--与国际传播学会(ICA)三任主席的学术对话 被引量:4
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作者 禹卫华 张国良 《新闻记者》 CSSCI 北大核心 2014年第2期30-34,共5页
2013年11月,国际传播学会(ICA)成立64年来第一次来到中国,在上海召开区域大会。会议期间,笔者与国际传播学会连续三任主席:辛西娅(Cynthia Stohl 2012—2013)、弗朗索瓦(Frangois Heinderyckx 2013—2014)、彼得(Peter Vorde... 2013年11月,国际传播学会(ICA)成立64年来第一次来到中国,在上海召开区域大会。会议期间,笔者与国际传播学会连续三任主席:辛西娅(Cynthia Stohl 2012—2013)、弗朗索瓦(Frangois Heinderyckx 2013—2014)、彼得(Peter Vorderer 2014-2015),进行了学术对谈,研讨了传播学趋势、理论、方法的变革,三位主席也对当前的一些热点以及中国传播学发展提出了各自的见解。 展开更多
关键词 传播学发展 国际传播 学术对话 学会 转型 中国
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Obesity, Body Fat Distribution, and Physical Activity in School-age Children: an Urban and Rural Comparison in Valparaíso, Chile 被引量:1
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作者 Pablo A Lizana Paula Cisternas-Vallejos +2 位作者 Leonel Araya Francisco Aguilera Manuel Mora 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2016年第11期834-839,共6页
This study analyze the relation between body composition, physical activity (PA), and sex in Chilean children from rural and urban public educational institutions. The prevalence of obesity (according to BMI) was ... This study analyze the relation between body composition, physical activity (PA), and sex in Chilean children from rural and urban public educational institutions. The prevalence of obesity (according to BMI) was 30.88% in urban children and 28.93% in rural children. Central obesity presented mainly in the rural girls. Approximately 90% of the participants reported 〈7 h of PA/week, regardless of residential area. In addition, central fat was strongly associated with rural residence; the children reported lower PA levels, and they presented a higher prevalence of central fat. The results reflect the need to implement programs to improve PA conditions in the child urban-rural population. 展开更多
关键词 an Urban and Rural Comparison in Valpara and Physical Activity in School-age Children SO Chile OBESITY
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Species,growth form,and biogeographic diversity of summit vegetation along an elevation gradient in the tropical Andes:a baseline for climate change monitoring
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作者 Luis D.LLAMBI Luis E.GAMEZ +6 位作者 Roxibell PELAYO Carmen J.AZOCAR Jesus E.TORRES Nelson J.MARQUEZ Monica B.BERDUGO Francisco CUESTA Lirey A.RAMIREZ 《Journal of Mountain Science》 SCIE CSCD 2022年第12期3441-3457,共17页
Tropical alpine ecosystems exhibit outstanding plant diversity and endemism while being particularly sensitive to the impacts of climate change.Although understanding spatiotemporal changes in plant species compositio... Tropical alpine ecosystems exhibit outstanding plant diversity and endemism while being particularly sensitive to the impacts of climate change.Although understanding spatiotemporal changes in plant species composition,richness and community structure along tropical alpine altitudinal gradients is of primary importance,both the functional and historical/biogeographic dimensions of vegetation diversity remain largely unexplored.We used Generalized Linear Models and multivariate analyses to assess changes in species,growth forms,and biogeographic groups richness and abundance,in response to habitat variables along an elevation gradient in seven summits(3800 to 4600 m asl)in the Venezuelan Andes,studied using the standardized approach of the GLORIA-Andes monitoring network.The habitat variables assessed were soil temperature(-10 cm),soil organic matter,slope inclination,and substrate cover.We found 113 species,representing72 genera,32 families,13 growth forms,and seven biogeographic origins,that included 25%of endemic elements.We observed richer vegetation,both in terms of species and growth forms,in summits with higher soil temperatures and higher SOM content,as well as higher biogeographic origin richness with increasing soil temperatures.The presence of holarctic elements increased toward higher elevations,while the occurrence of austral antarctic elements increased toward lower elevations.Our results indicate that biogeographic and functional approaches to vegetation diversity capture well the effect of abiotic filtering on community structuring in these tropical alpine environments.These findings constitute an important baseline for monitoring vegetation dynamics linked to climate change in the Venezuelan Andes by highlighting the functional and historical perspective on vegetation analyses,in contrast with more traditional approaches,based only on taxonomic species diversity. 展开更多
关键词 Alpine vegetation BIOGEOGRAPHY Elevation gradient Functional diversity Páramo Soil organic matter Temperature Tropical Andes
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An estimation of stress intensity factor in a clamped SE(T) specimen through numerical simulation and experimental verification:case of FCGR of AISI H11 tool steel 被引量:4
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作者 Masood Shah Catherine Mabru +2 位作者 Farhad Rezai-Aria Ines Souki Riffat Asim Pasha 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2012年第4期307-319,共13页
A finite element analysis of stress intensity factors (KI) in clamped SE(T)c specimens (dog bone profile) is presented. A J-integral approach is used to calculate the values of stress intensity factors valid for... A finite element analysis of stress intensity factors (KI) in clamped SE(T)c specimens (dog bone profile) is presented. A J-integral approach is used to calculate the values of stress intensity factors valid for 0.125≤a/W≤0.625. A detailed comparison is made with the work of other researchers on rectangular specimens. Different boundary conditions are explored to best describe the real conditions in the laboratory. A sensitivity study is also presented to explore the effects of variation in specimen position in the grips of the testing machine. Finally the numerically calculated SIF is used to determine an FCGR curve for AISI Hll tool steel on SE(T)c specimens and compared with C(T) specimen of the same material. 展开更多
关键词 Fatigue crack propagation Stress intensity factor J-INTEGRAL Paris law
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Identification of Phenolic Compounds from K.ivorensis by Selected Chromatographic and Spectrometric Techniques 被引量:1
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作者 A.Bikoro Bi Athomo S.P.Engozogho Anris +3 位作者 R.Safou Tchiama F.Eyma C.Arnaudguilhem B.Charrier 《Journal of Renewable Materials》 SCIE EI 2021年第1期35-48,共14页
A complementary approach using Liquid Chromatographic-Mass Spectrometric analysis was proposed to characterize phenolic compounds from the methanol-water extracts of K.ivorensis A.Chev.Two High Performance Liquid Chro... A complementary approach using Liquid Chromatographic-Mass Spectrometric analysis was proposed to characterize phenolic compounds from the methanol-water extracts of K.ivorensis A.Chev.Two High Performance Liquid Chromatography(HPLC)complementary methods were used for the determination of phenolic compounds from the bark,sapwood and heartwood of K.ivorensis.Methods employed involved direct analysis after filtration at 0.20μm,using a RP C18 column and UV-VIS/ESI-FTMS detection.The methods used were different by their elution gradient and allowed analyzing the chemical composition of three parts of African mahogany extracts.In this study,22 phenolic compounds and derivatives from K.ivorensis were separated,determined or tentatively characterized for the first time based on their methanol/water/formic acid extract mass spectra.The difference of gradients eluted various compounds,8 were obtained with the first method and 14 with the second one.The main products were hydroxybenzoic acid and derivatives,resorcinol,esterified compounds,mannitol,quercetin and derivatives,dihydroxyflavan,and trihydroxyflavan. 展开更多
关键词 BARK RP_HPLC ESI-FTMS SAPWOOD HEARTWOOD K.ivorensis phenolic compounds
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Vibration-assisted vat photopolymerization for pixelated-aliasing-free surface fabrication
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作者 Han Xu Renzhi Hu +3 位作者 Shuai Chen Junhong Zhu Chi Zhou Yong Chen 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第3期440-456,共17页
Mask image projection-based vat photopolymerization(MIP-VPP)offers advantages like low cost,high resolution,and a wide material range,making it popular in industry and education.Recently,MIP-VPP employing liquid cryst... Mask image projection-based vat photopolymerization(MIP-VPP)offers advantages like low cost,high resolution,and a wide material range,making it popular in industry and education.Recently,MIP-VPP employing liquid crystal displays(LCDs)has gained traction,increasingly replacing digital micromirror devices,particularly among hobbyists and in educational settings,and is now beginning to be used in industrial environments.However,LCD-based MIP-VPPsuffers from pronounced pixelated aliasing arising from LCD’s discrete image pixels and itsdirect-contact configuration in MIP-VPP machines,leading to rough surfaces on the 3D-printed parts.Here,we propose a vibration-assisted MIP-VPP method that utilizes a microscalevibration to uniformize the light intensity distribution of the LCD-based mask image on VPP’s building platform.By maintaining the same fabrication speed,our technique generates asmoother,non-pixelated mask image,reducing the roughness on flat surfaces and boundary segments of 3D-printed parts.Through light intensity modeling and simulation,we derived an optimal vibration pattern for LCD mask images,subsequently validated by experiments.We assessed the surface texture,boundary integrity,and dimensional accuracy of componentsproduced using the vibration-assisted approach.The notably smoother surfaces and improved boundary roughness enhance the printing quality of MIP-VPP,enabling its promisingapplications in sectors like the production of 3D-printed optical devices and others. 展开更多
关键词 additive manufacturing vat photopolymerization piezo vibration sub-pixel resolution ALIASING
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Author correction to“The neuroprotective effect of traditional Chinese medicinal plants-A critical review”[Acta Pharm Sin B 13(2023)3208-3237]
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作者 João Moreira Mariana Machado +3 位作者 Mónica Dias-Teixeira Ricardo Ferraz Cristina Delerue-Matos Clara Grosso 《Acta Pharmaceutica Sinica B》 2025年第4期2300-2300,共1页
Unfortunately,in the article The neuroprotective effect of traditional Chinese medicinal plantsdA critical review by Moreira et al.(Acta Pharmaceutica Sinica B 13(2023)3208-3237)some data have not been corrected in th... Unfortunately,in the article The neuroprotective effect of traditional Chinese medicinal plantsdA critical review by Moreira et al.(Acta Pharmaceutica Sinica B 13(2023)3208-3237)some data have not been corrected in the proofreading stage:Page 3225 e In the study by Lim et al.^(234). 展开更多
关键词 critical review neuroprotective effect traditional chinese medicinal plants traditional chinese medicinal plantsda
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Endocrine-disrupting compounds in urban rivers of the southern border of Mexico:Occurrence and ecological risk assessment
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作者 Khirbet Lopez-Velazquez Jose G.Ronderos-Lara +5 位作者 Hugo A.Saldarriaga-Norena Mario A.Murillo-Tovar Minerva Villanueva-Rodríguez Jorge L.Guzman-Mar Edwin R.Hoil-Canul Jose L.Cabellos-Quiroz 《Emerging Contaminants》 2025年第1期563-571,共9页
The occurrence of seven endocrine-disrupting compounds(EDCs)in four urban rivers on the southern border of Mexico was studied in this work.The selected EDCs were 17b-estradiol(E2),estriol(E3),17aethinylestradiol(EE2),... The occurrence of seven endocrine-disrupting compounds(EDCs)in four urban rivers on the southern border of Mexico was studied in this work.The selected EDCs were 17b-estradiol(E2),estriol(E3),17aethinylestradiol(EE2),bisphenol A(BPA),bisphenol F(BPF),4-nonylphenol(4NP)and 4-tert-octylphenol(4TOP).Water samples from the Coatan,Texcuyuapan,Cahoacan,and Coatancito rivers were collected at three different sites on each river and processed by solid phase extraction(SPE).The samples were analyzed by gas chromatography triple quadrupole tandem mass spectrometry(GC-MS/MS)and compounds of interest were identified by dynamic mass reaction monitoring mode(dMRM).Among the target EDCs,E2,BPA,and 4NP were detected in all water samples,with BPA being the most abundant ranging from 4.22 up to 127.96 ng/L.Correlation tests showed significant positive associations between estrogens and BPA,as well as the correlation between alkylphenols and BPA,suggesting common origin emission sources,which were identified as discharges of untreated municipal wastewater.Finally,the estimation of RQ and EEQ values indicated that the presence of E2,E3,EE2,and BPA in all sampled points represents a high risk for aquatic life in these sites,mainly for Texcuyuapan River,where the aquatic organisms may be susceptible to endocrine disruption by chronic exposure to detected compounds. 展开更多
关键词 Environmental risk GC-MS/MS Urban rivers Water pollution WASTEWATER
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Wildlife hunting and the increased risk of leprosy transmission in the tropical Americas:a pathogeographical study
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作者 Alisa Aliaga-Samanez Patricia D.Deps +13 位作者 Julia E.Fa Raimundo Real Jean-François Guégan Marcela A.Oliveira Aline Pessutti Simon Knoop Juliano A.Bogoni Thais Q.Morcatty Roberta Marques Daniel Jiménez-García Gabriel F.Massocato Arnaud L.Desbiez Danilo Kluyber Hani R.El Bizri 《Infectious Diseases of Poverty》 2025年第3期100-101,共2页
Background Leprosy remains a persistent public health challenge,where human-to-human transmission of Mycobacterium leprae via respiratory droplets is well established.In the tropical Americas,growing evidence implicat... Background Leprosy remains a persistent public health challenge,where human-to-human transmission of Mycobacterium leprae via respiratory droplets is well established.In the tropical Americas,growing evidence implicates armadillos as important zoonotic reservoirs,particularly through direct contact during hunting and handling.However,such transmission has so far been considered rare and highly localised.This study provides a comprehensive spatial analysis of the role of armadillo hunting in human leprosy transmission,quantifying its contribution to disease prevalence and identifying geographic hotspots where interventions could be most effective.Methods Using Brazil’s 326,001 reported leprosy cases from 2013 to 2022,we applied a pathogeographical approach to explore transmission dynamics.We compiled data on 554 hunted armadillos across 175 municipalities and M.leprae prevalence in 376 armadillo individuals from 97 municipalities(mean prevalence=38.5%).These were used to build spatial models assessing hunting-related infection risk and integrated as a variable into a generalised linear model alongside socioeconomic,climatic,and environmental predictors to evaluate their effects on human leprosy prevalence.Results Key predictors of armadillo hunting included higher population density(P<0.001)and firearm availability(P<0.01).Infection in armadillos was negatively correlated with native habitat coverage(coefficient:−2.28;P<0.001),suggesting that environmental degradation can amplify infection risk.The armadillo-hunting infection risk variable—generated by combining armadillo hunting and infection favourability models—emerged as the second strongest predictor of human leprosy prevalence(coefficient:1.69;P<0.001),accounting for~25%of cases nationally and around 40%in deforestation hotspots.Additional positive predictors included greater precipitation seasonality(coefficient:0.82;P<0.001)and malnutrition(coefficient:0.01;P<0.001),while higher population density(coefficient:−0.64;P<0.001),natural habitat coverage(coefficient:−0.50;P<0.001)and socioeconomic status(coefficient:−0.47;P=0.013)were linked to reduced disease prevalence.Conclusions Armadillo hunting seems to play a more significant role in human leprosy transmission than previously recognised.To address this overlooked pathway,targeted interventions should focus on reducing unsafe and illegal hunting,improving communication around zoonotic risks,strengthening disease surveillance in high-risk areas,and conducting genetic studies to confirm wildlife-to-human transmission.Our findings highlight the importance of incorporating wildlife-associated transmission pathways into strategies to reduce disease prevalence and mitigate future outbreaks in tropical regions facing rapid environmental change and persistent poverty. 展开更多
关键词 Disease ecology Human-animal interaction ARMADILLO Mycobacterium leprae Zoonotic diseases Pathogeography
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Carbon fibres reinforced composites.Electrical impedance analysis:a gateway to smartness 被引量:1
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作者 Philippe Margueres Philippe Olivier +2 位作者 Mahamadou Mounkaila Sonia Sassi Thierry Camps 《International Journal of Smart and Nano Materials》 SCIE EI 2020年第4期417-430,共14页
For more than 7 years,our research work is focussed upon the electrical behavior of carbon fiber reinforced composites.Effectively carbon/polymeric matrix laminates can be considered as an electri-cally conductive net... For more than 7 years,our research work is focussed upon the electrical behavior of carbon fiber reinforced composites.Effectively carbon/polymeric matrix laminates can be considered as an electri-cally conductive network(i.e.carbon fibers)embedded in an insulat-ing medium(i.e.the polymeric matrix).Consequently,from an electrical point of view laminated composites have been modelled owing to combinations of electrical resistances(i.e.fibers themselves and the contact points between the fibers)and capacitances(i.e.polymeric matrix).During their manufacturing,composite material such as thermoset matrix composites for instance,undergo various changes in their physical(including electrical and mechanical)prop-erties and in their geometrical characteristics.In fact,in the case of manufacturing processes such as oven curing(vacuum bag),auto-clave curing or heating plate press,beside the chemo-rheologi-cal changes,the laminated parts are the place of a compaction phenomenon inducing changes in fiber volume fraction and thick-nesses.The idea developed in this paper is that since the carbon/polymeric matrix laminate can be considered as an electrical network,it can then be view and used as a sensor for following the material state during the manufacturing process enabling thus defects to be detected and this without any additional sensing material or device. 展开更多
关键词 Electrical impedancemetry cure monitoring CFRP FUNCTIONALIZATION SHM
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气相色谱-质谱法测定化妆品中11种全氟化合物
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作者 魏珍珍 李宁 +3 位作者 刘洋 缪娟 刘晓萌 刘娜 《化学分析计量》 2026年第1期41-48,共8页
建立同时测定化妆品中11种全氟化合物(PFCs)的气相色谱-质谱联用分析方法。以乙腈-丙酮(体积比为7∶3)混合溶液为提取溶剂,对化妆品样品进行超声提取,提取液经固相萃取柱净化富集后,采用HP-5MS毛细管柱(30 m×0.25 mm,0.25μm)分离... 建立同时测定化妆品中11种全氟化合物(PFCs)的气相色谱-质谱联用分析方法。以乙腈-丙酮(体积比为7∶3)混合溶液为提取溶剂,对化妆品样品进行超声提取,提取液经固相萃取柱净化富集后,采用HP-5MS毛细管柱(30 m×0.25 mm,0.25μm)分离,利用选择离子监测模式检测,以外标法定量。11种PFCs的质量浓度在0.01~1.0μg/mL范围内与色谱峰面积线性关系良好,相关系数均不小于0.998,方法检出限为0.001~0.005μg/g,定量限为0.003~0.02μg/g。低、中、高3个加标水平的平均回收率为82.5%~108%, 6次测定结果的相对标准偏差为2.1%~7.2%。该方法适用于化妆品中挥发/半挥发、弱极性或非离子型PFCs的高通量筛查与定量分析,为化妆品中多类别PFCs的质量安全监管提供技术支持。 展开更多
关键词 气相色谱-质谱法 化妆品 全氟化合物
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New approaches to treating chronic obstructive pulmonary disease with Colla corii asini
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作者 Wenchao Zhang Siman Sun +3 位作者 Xiaoyu Fan Jiuming He Qing Li Hongtao Jin 《Animal Models and Experimental Medicine》 2026年第1期50-58,共9页
Chronic obstructive pulmonary disease(COPD)is one of the leading causes of death and disability worldwide.Its complex etiology involves factors such as smoking,air pollution,genetic susceptibility,and social environme... Chronic obstructive pulmonary disease(COPD)is one of the leading causes of death and disability worldwide.Its complex etiology involves factors such as smoking,air pollution,genetic susceptibility,and social environment.With the accelerating global aging population and urbanization,the incidence and burden of COPD continue to rise.Current treatment strategies for COPD are relatively conservative,primarily focusing on bronchodilators,inhaled corticosteroids,and long-term oxygen therapy.Although these approaches can alleviate symptoms and slow disease progression to some ex-tent,they fail to effectively target the underlying mechanisms of the disease,leaving an unmet clinical need for more-effective therapies.This highlights the urgency of de-veloping innovative drugs that are both safe and efficacious to address the challenges in COPD treatment.As a traditional Chinese medicine with a long history,Colla corii asini has garnered significant attention for its diverse pharmacological effects and fa-vorable safety profile.Research has shown that Colla corii asini possesses multiple bio-logical activities,including hematopoiesis,nourishing the lungs,enhancing immunity,anti-infection,antiaging,antitumor,and antifatigue effects.Moreover,it has demon-strated potential in regulating oxidative stress,immune imbalance,and inflammatory responses.Recent evidence suggests that Colla corii asini may play a protective role in lung function through multitarget and multipathway mechanisms.Based on previ-ous research findings,this paper explores the potential therapeutic value of Colla corii asini in COPD treatment by addressing the current clinical management challenges and identifying potential therapeutic targets.It also integrates the pharmacological effects of Colla corii asini into a broader treatment context,providing new perspec-tives for comprehensive COPD management and laying the theoretical foundation for its modernization and innovative application. 展开更多
关键词 chronic obstructive pulmonary disease Colla corii asini PHARMACOLOGY therapeutic targets
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Modeling xeroderma pigmentosum associated neurological pathologies with patients-derived iPSCs 被引量:11
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作者 Lina Fu Xiuling Xu +15 位作者 Ruotong Ren Jun Wu Weiqi Zhang Jiping Yang Xiaoqing Ren Si Wang Yang Zhao Liang Sun Yang Yu Zhaoxia Wang Ze Yang Yun Yuan Jie Qiao Juan Carlos Izpisua Belmonte Jing Qu Guang-Hui Liu 《Protein & Cell》 SCIE CAS CSCD 2016年第3期210-221,共12页
Xeroderma pigmentosum (XP) is a group of genetic disorders caused by mutations of XP-associated genes, resulting in impairment of DNA repair. XP patients frequently exhibit neurological degeneration, but the underly... Xeroderma pigmentosum (XP) is a group of genetic disorders caused by mutations of XP-associated genes, resulting in impairment of DNA repair. XP patients frequently exhibit neurological degeneration, but the underlying mechanism is unknown, in part due to lack of proper disease models. Here, we generated patientspecific induced pluripotent stem cells (iPSCs) harboring mutations in five different XP genes including XPA, XPB, XPC, XPG, and XPV. These iPSCs were further differentiated to neural cells, and their susceptibility to DNA damage stress was investigated. Mutation of XPA in either neural stem cells (NSCs) or neurons resulted in severe DNA damage repair defects, and these neural cells with mutant XPA were hyper-sensitive to DNA damage-induced apoptosis. Thus, XP-mutant neural cells represent valuable tools to clari the molecular mechanisms of neurological abnormalities in the XP patients. 展开更多
关键词 xeroderma pigmentosum IPSC disease model neural stem cell. neuron
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US Presidential Election 2008:Policy Implications for US-China Trade and Investment
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作者 Dan Steinbock 《China & World Economy》 SCIE 2008年第3期40-56,共17页
The next US president will be elected in November 2008. Since the relative stabilization of war in Iraq, the economy has become the national priority of the 2008 US election. In their campaign efforts, the Democrats h... The next US president will be elected in November 2008. Since the relative stabilization of war in Iraq, the economy has become the national priority of the 2008 US election. In their campaign efforts, the Democrats have enjoyed greater momentum than the Republicans, in terms of polls, fund-raising and corporate support. After the Bush era, the next president will seek to restore America's leadership and to engage in multilateralism. Since the 1990s, China has been the most rapidly-growing US export destination. In terms of US-Shinese trade and investment, the next president, ira Democrat, will, among other issues, review trade agreements and has pledged to co-sponsor legislation that would allow US companies to seek anti-dumping duties on Chinese imports based on the perceived undervaluation of the Chinese currency. If a Republican, the next president will support global integration and oppose protectionist measures. The Democratic Congress is likely to oppose Republican policies in general and free trade policies in particular. Both scenarios imply increasing pressure on US-Chinese trade and investment relationships. Because these two nations now account for almost half of global growth, the state of the futureUS-Chinese bilateral relationship has worldwide implications. 展开更多
关键词 foreign trade agreements trade and investment US-Chinese relations
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Extreme drought triggers parallel shifts in wood anatomical and physiological traits in upper treeline of the Mediterranean Andes
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作者 Luiz Santini Jr. Dylan Craven +6 位作者 Daigard Ricardo Ortega Rodriguez Manolo Trindade Quintilhan Stephanie Gibson‑Carpintero Cristina Aravena Torres Fidel A.Roig Ariel A.Muñoz Alejandro Venegas‑Gonzalez 《Ecological Processes》 CSCD 2024年第1期132-143,共12页
Background Treeline ecotones of Mediterranean ecoregions have been affected by the increasing intensity and severity of droughts.Even though the effect of droughts on forest dynamics has been widely documented,knowled... Background Treeline ecotones of Mediterranean ecoregions have been affected by the increasing intensity and severity of droughts.Even though the effect of droughts on forest dynamics has been widely documented,knowledge is relatively scarce of how extreme climate episodes affect the hydraulic structure and,therefore,the phys-iology of woody plants.The Mediterranean Andes have experienced an uninterrupted period of drought since 2010,including an extremely dry year in 2019 with approximately 80%rainfall deficit.Here,we investigated shifts in wood anatomical and physiological traits of Kageneckia angustifolia,an endemic treeline species,in response to this drought period.Methods We evaluated the xylem plasticity of three K.angustifolia populations across their natural distribution(31–35°SL)based on anatomical(vessel structure and distribution)and physiological(intrinsic water-use efficiency)variables in the tree rings.We focused on the period 2000–2020 that corresponds to before the megadrought(2000–2007),(ii)megadrought(2008–2018)and(iii)hyperdrought(2019–2020).The variables were annualized and analyzed by linear mixed-effects models.Results Our results provide insights to the anatomical and physiological mechanisms underlying the resilience of treeline forests to persistent droughts in central Chile.We found that the extreme drought in 2019–2020 triggered shifts in vessel size and frequency that increased hydraulic safety.These significant shifts in vessel traits occurred in parallel with a decrease in pit aperture area and an increase in water-use efficiency,further increasing the resilience of K.angustifolia to extreme drought stress.Conclusions Our results revealed coordinated shifts in vessel size and frequency and water-use efficiency in response to the megadrought,thereby reducing vulnerability to hydraulic failure.The apparent resilience of K.angustifolia to extreme droughts suggests that this adaptation to drought stress may increase its ability to tolerate novel climatic conditions of treeline environments of the Mediterranean Andes,although it is not clear whether these adaptations will be sufficient to persist in scenarios that predict intensification of climate stress.Finally,our results provide empirical evidence that integrating wood anatomical and physiological traits facilitates the understanding of resilience mechanisms that treeline forests develop in the face of increasing drought stress. 展开更多
关键词 Dendro-anatomy Kageneckia angustifolia Xylem vulnerability Drought Climate change
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一种评价角质细胞更新的人体功效可视化方法
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作者 邱思敏 赵春霞 张大为 《香料香精化妆品》 2025年第1期140-143,共4页
探讨了一种评价角质细胞更新的人体功效可视化方法。通过二羟丙酮对皮肤染色后,采用Skin-Colorimeter CL400型皮肤颜色测试仪测得不同时间点的皮肤个体类型角(ITA°)值,并由此得出角质细胞更新率,以此评价测试产品的促进角质更新效... 探讨了一种评价角质细胞更新的人体功效可视化方法。通过二羟丙酮对皮肤染色后,采用Skin-Colorimeter CL400型皮肤颜色测试仪测得不同时间点的皮肤个体类型角(ITA°)值,并由此得出角质细胞更新率,以此评价测试产品的促进角质更新效果。结果显示,使用测试样品第14天时,与空白对照组相比,皮肤ITA°值有显著性差异,且角质层更新率为71.66%,显著优于空白对照组的50.12%。试验结果提示二羟丙酮染色法是去角质功效评价的有效手段,通过使用样品前后皮肤ITA°值和角质细胞更新率指标可进一步量化角质更新的效果。 展开更多
关键词 角质细胞更新 二羟丙酮 皮肤颜色 甘醇酸 角质层
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舒敏类化妆品的人体功效评价方法
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作者 邱思敏 赵春霞 张大为 《香料香精化妆品》 2025年第1期84-89,共6页
概述了敏感皮肤的发生机制,介绍了舒敏类化妆品的人体功效评价方法,包括诱导人体皮肤刺激模型法和人体开放使用测试法。比较了不同方法之间的异同、优缺点和适用的功效作用机理,旨在为舒敏类化妆品的功效评价提供理论依据。
关键词 敏感性皮肤 化妆品 功效 评价
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Finite Element Analysis of Inclusion Stiffness and Interfacial Debonding on the Elastic Modulus and Strength of Rubberized Mortar
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作者 Cristian Martínez-Fuentes Pedro Pesante +1 位作者 Karin Saavedra Paul Oumaziz 《Computers, Materials & Continua》 2025年第10期581-595,共15页
Rubberized concrete is one of the most studied applications of discarded tires and offers a promising approach to developing materials with enhanced properties.The rubberized concrete mixture results in a reduced modu... Rubberized concrete is one of the most studied applications of discarded tires and offers a promising approach to developing materials with enhanced properties.The rubberized concrete mixture results in a reduced modulus of elasticity and a reduced compressive and tensile strength compared to traditional concrete.This study employs finite element simulations to investigate the elastic properties of rubberized mortar(RuM),considering the influence of inclusion stiffness and interfacial debonding.Different homogenization schemes,including Voigt,Reuss,and mean-field approaches,are implemented using DIGIMAT and ANSYS.Furthermore,the influence of the interfacial transition zone(ITZ)between mortar and rubber is analyzed by periodic homogenization.Subsequently,the influence of the ITZ is examined through a linear fracture analysis with the stress intensity factor as a key parameter,using the ANSYS SMART crack growth tool.Finally,a non-linear study in FEniCS is carried out to predict the strength of the composite material through a compression test.Comparisons with high density polyethylene(HDPE)and gravel inclusions show that increasing inclusion stiffness enhances compressive strength far more effectively than simply improving the mortar/rubber bond.Indeed,when the inclusions are much softer than the surrounding matrix,any benefit gained on the elastic modulus or strength from stronger interfacial adhesion becomes almost negligible.This study provide numerical evidence that tailoring the rubber’s intrinsic stiffness—not merely strengthening the rubber/mortar interface—is a decisive factor for improving the mechanical performance of RuM. 展开更多
关键词 Rubberized mortar elastic modulus compression strength DEBONDING
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