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Temporal dynamics of shallow subtidal meiobenthos from a beach in Tenerife (Canary Islands, northeast Atlantic Ocean)
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作者 Rodrigo Riera Jorge Núez María del Carmen Brito 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第8期44-54,共11页
A shallow subtidal (3 m deep) meiofaunal assemblage in Los Abrigos Bay, Tenerife, Canary Islands was sam- pled during May 2000-April 2001. The main aims were to (1) find temporal variations in meiofaunal assem- bl... A shallow subtidal (3 m deep) meiofaunal assemblage in Los Abrigos Bay, Tenerife, Canary Islands was sam- pled during May 2000-April 2001. The main aims were to (1) find temporal variations in meiofaunal assem- blage structure and overall abundance, as well as in the most abundant meiofaunal species throughout the study period, and (2) identify environmental variables (sedimentary composition, organic matter content, and total nitrogen) that better explain meiofaunal assemblage structure during the study year. The most abundant species were the nematodes Siphonolaimus sp. 2 and Catanema sp., which represented 46.2% of the overall meiofaunal abundances and varied significantly throughout the study duration. Overall meio- faunal abundance and the most abundant taxonomic groups (nematodes, copepods, and oligochaetes) showed significant temporal variations during the study period. Nematodes overwhelmingly dominated during the study period, ranging from 78% in May to 97.34% in February. Multivariate analyses showed seasonality in meiofaunal community structure during the study year, with the lowest abundances in May. Keywords: Meiofauna, assemblage structure, subtidal, Canary Islands, Atlantic Ocean 展开更多
关键词 MEIOFAUNA assemblage structure SUBTIDAL Canary Islands Atlantic Ocean
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Macrofaunal communities of threatened subtidal maёrl seabeds on Tenerife (Canary Islands, north-east Atlantic Ocean) in summer
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作者 Rodrigo Riera Juan Domingo Delgado +2 位作者 Myriam Rodríguez Óscar Monterroso Eva Ramos 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2012年第1期98-105,共8页
This study contributes with the first data on physical and taxonomical structure of macrofaunal assemblages of maerl beds from the Canary Islands. Maerl beds and Cymodocea nodosa meadows of the Canary Islands are cons... This study contributes with the first data on physical and taxonomical structure of macrofaunal assemblages of maerl beds from the Canary Islands. Maerl beds and Cymodocea nodosa meadows of the Canary Islands are considered biodiversity hot-spots in terms of taxonomic and functional biodiversity with a broad geographical and depth ranges. The authors have studied the structure of the macrofaunal assemblages on different habitat types (Cymodocea, Caulerpa, sabellid field, garden eel and maerl beds). Samples were taken at a range of depths between 14 and 46 m. Correlations were performed among abiotic variables (granulometry, organic matter, nitrogen and phosphates) and the most abundant taxa. Similarity analysis was performed to explore the patchiness of seabeds at a local scale. Significant differences were found in macrofaunal assemblages among seabed types, with highest abundances and lowest biodiversity in sabellid fields, where the sabellid Bispira viola dominated. The polychaetes Aponuphis bilineata and Chone filicauda and the mollusc Turritella brochii were the most abundant taxa on maerl beds. The mosaic of granulometric conditions would explain the associated macroinfaunal community structure and contribute to the creation of diversity on these relatively well preserved seabeds at a local scale. 展开更多
关键词 Macrofauna POLYCHAETES Amphipods Molluscs soft-bottoms SUBTIDAL TENERIFE Canary Islands
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Soil and Phytosociological Characterisation of Grasslands in the Western Mediterranean
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作者 A. Cano-Ortiz E. Bioindi +2 位作者 C. J. Pinto Gomes S. Del Río González E. Cano 《American Journal of Plant Sciences》 2014年第21期3213-3240,共28页
A study was made of grasslands in olive groves with a high frequency of Hordeum leporinum Link, Chrysanthemum coronarium L., Malva neglecta Wallr., Aegilops geniculata Roth and Dasypyrum villosum (L.) Borbas, initiall... A study was made of grasslands in olive groves with a high frequency of Hordeum leporinum Link, Chrysanthemum coronarium L., Malva neglecta Wallr., Aegilops geniculata Roth and Dasypyrum villosum (L.) Borbas, initially included in the alliance Hordeion leporini Br.-Bl. in Br.-Bl., Gajewski, Wraber & Walas 1936 corr. O. Bolós 1962, and sub-alliance Malvenion neglectae Gutte 1966. The study was carried out in the western Mediterranean (Spain, Italy, Portugal and northern Morocco). The soil and phytosociological treatment of the samples contributes information for new plant communities. In the study of plant communities, the indices of degree of presence are adapted to those of Van der Maarel. The new alliance Securigero securidacae-Dasypyrion villosi is proposed for the sub-Mediterranean and Euro-Siberian territories, with the new communities Securigero securidacae-Dasypyretum villosi and Convolvulo elegantissimi-Aegilopetum geniculatae. This last community, due to its richness in Aegilops geniculata Roth, could be included in the alliance Taeniathero-Aegilopion geniculatae Rivas-Martínez & Izco 1977;however, the soil and statistical analyses reveal that it should remain part of the alliance Securigero securidacae-Dasypyrion villosi. The soil and floristic study of Hordeion leporini and Malvenion neglectae allows us to describe the new sub-alliance Resedo albae-Chrysanthemenion coronarii, subordinated to Malvion neglectae (Gutte 1966) status novo. 展开更多
关键词 SOIL GRASSLAND COMMUNITY ASSOCIATION
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热带杂交水稻组合SL-8H 被引量:2
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作者 胡继银 张昭东 +2 位作者 蒋葆华 白德朗 傅适 《杂交水稻》 CSCD 北大核心 2014年第1期87-88,共2页
SL-8H是菲律宾西领农业技术公司(SL Agritech Corporation)用三系不育系粤泰A与恢复系9311配组育成的热带杂交水稻组合,具有产量高、米质较优、熟期适宜、适合热带栽培等特点,2004年通过菲律宾国家审定。介绍了其选育过程、特征特性及... SL-8H是菲律宾西领农业技术公司(SL Agritech Corporation)用三系不育系粤泰A与恢复系9311配组育成的热带杂交水稻组合,具有产量高、米质较优、熟期适宜、适合热带栽培等特点,2004年通过菲律宾国家审定。介绍了其选育过程、特征特性及栽培和制种技术要点。 展开更多
关键词 杂交水稻 SH-8H 热带 选育
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Using organotypic hippocampal slice cultures to gain insight into mechanisms responsible for the neuroprotective effects of meloxicam: a role for gamma aminobutyric and endoplasmic reticulum stress
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作者 Elisa Landucci Irene L.Llorente +2 位作者 Berta Anuncibay-Soto Domenico E.Pellegrini-Giampietro Arsenio Fernández-López 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第1期65-66,共2页
This perspective aims to put into context the recent article by Landucci et al.(2018)on mechanisms involved in the neuroprotective effects of meloxicam on an organotypic hippocampal slice cultures(OHSCs)model.In vitro... This perspective aims to put into context the recent article by Landucci et al.(2018)on mechanisms involved in the neuroprotective effects of meloxicam on an organotypic hippocampal slice cultures(OHSCs)model.In vitro cell cultures are the main method for studying large quantities of homogeneous cells in an isolated environment.Thus,the use of primary dissociated neuron,astrocyte,oligodendrocyte,microglia,or endothelial cell cultures has become a standard 展开更多
关键词 GAMMA 文化 海马 机制 应力 蜂窝 环境学习
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无限级固井滑套密封胶筒参数敏感性分析及优化
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作者 薛宪波 华泽君 +5 位作者 祝效华 刘海军 张诚成 曲跃 石昌帅 程飞龙 《润滑与密封》 北大核心 2025年第1期129-137,共9页
针对目前常规的固井滑套分段压裂技术在深井超深井中存在工具管串下入性差、安全性低、开采效率不高等问题,提出一种无限级键槽式固井滑套,并设计配套的梭镖和新型中间三胶筒结构。基于橡胶热疲劳老化力学性能实验,建立梭镖胶筒三维动... 针对目前常规的固井滑套分段压裂技术在深井超深井中存在工具管串下入性差、安全性低、开采效率不高等问题,提出一种无限级键槽式固井滑套,并设计配套的梭镖和新型中间三胶筒结构。基于橡胶热疲劳老化力学性能实验,建立梭镖胶筒三维动力学数值模型,研究防突环结构和胶筒结构对密封性能的影响规律。研究结果表明:当防突环的数量为2和防突环的开槽数为4时,胶筒的最小密封压力达到最大;胶筒长度对密封压力有显著影响,随着中间胶筒长度的增加,最小密封压力整体呈先增大后减小的趋势;胶筒的不同开孔形状对胶筒密封性能影响显著;当梭镖中间胶筒长度为125 mm时,开孔形状为半圆形且开孔半径为3~5 mm时,密封压力高,密封效果最好。 展开更多
关键词 胶筒密封 无限级键槽式固井滑套 参数优化 密封性能 敏感性分析
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“i7算”赋能AI产业生态可持续发展 被引量:3
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作者 戎珂 施新伟 吕若明 《科学学研究》 北大核心 2025年第1期197-204,共8页
本文深入分析了数字经济时代下人工智能(Artificial Intelligence,AI)商业化落地以及其产业生态可持续发展中存在的问题,针对性地提出了“i7算”框架,集成(integrate)算据、算法、算力、算知、算者、算景和算理七大要素。“i7算”框架... 本文深入分析了数字经济时代下人工智能(Artificial Intelligence,AI)商业化落地以及其产业生态可持续发展中存在的问题,针对性地提出了“i7算”框架,集成(integrate)算据、算法、算力、算知、算者、算景和算理七大要素。“i7算”框架以算据、算法、算力等构建硬实力的AI基础设施,深耕算知、算景推进AI技术商业化应用,多层次系统化培育算者,充分落实行业应用规范、积极回应社会伦理关切,形成良好文化纽带推动产业生态内各伙伴共创共赢,实现可持续发展。本研究认为,在商业化落地过程中,AI产业生态里的核心企业,需要与关键生态合作伙伴共同建设AI基础设施,推动AI技术的商业化应用,与AI行业伙伴共同培育可持续文化纽带,以此吸引和带动更多AI生态伙伴,从而共同推动AI产业生态的可持续发展。 展开更多
关键词 人工智能 商业生态 商业模式 可持续发展
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Environmental Factors Influencing Poor Waste Management amongst Inhabitants in Western Area Rural in Sierra Leone
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作者 Philip John Kanu Turay Hamid Abdulai K. Kandeh 《Journal of Environmental Protection》 2025年第2期111-129,共19页
Background: Waste management in Western Area Rural (WAR), Sierra Leone, is plagued by infrastructural and socioeconomic challenges, leading to environmental and health hazards such as flooding, air pollution, and vect... Background: Waste management in Western Area Rural (WAR), Sierra Leone, is plagued by infrastructural and socioeconomic challenges, leading to environmental and health hazards such as flooding, air pollution, and vector-borne diseases. Despite awareness campaigns, informal methods like open dumping and burning dominate. This study applies the Theory of Planned Behaviour (TPB) to analyse how attitudes, subjective norms, and perceived behavioural control influence waste management practices and barriers to proper disposal with potential solutions. Methods: A quantitative approach was employed, using stratified random sampling and structured questionnaires to collect data from 333 participants across ten communities in Western Area Rural (WAR). Data were analyzed using descriptive and inferential statistics to examine the relationship between socio-demographic variables and waste management practices. Results: While 98.2% of respondents acknowledged the importance of waste management, limited perceived behavioural control driven by financial constraints (83.8%), inadequate education (83.2%), and insufficient infrastructure (66.4%) hindered effective waste disposal ultimately linking health and environmental risks, such as flooding and marine pollution from plastic waste. Most respondents (68.8%) lacked access to formal waste services, with disposal occurring primarily via open dumping (62.9%) and burning (17.9%). Subjective norms reinforced informal disposal, as community waste-burning remained an accepted practice. Women were disproportionately affected due to economic constraints and larger household sizes. Despite these challenges, 93.1% were willing to engage in community clean-up efforts, indicating strong pro-environmental attitudes constrained by structural barriers. Conclusion: Findings underscore the need for integrated waste management strategies informed by TPB, targeting attitudes through education, reshaping social norms through community-driven initiatives, and enhancing perceived behavioural control by improving infrastructure and financial accessibility. Addressing gender disparities, strengthening public-private partnerships, and expanding recycling and composting programs can foster sustainable waste management in resource-constrained settings. 展开更多
关键词 Waste Management Theory of Planned Behaviour Environmental Health Gender Disparities RECYCLING Community Engagement Infrastructure Public-Private Partnerships
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The Role of Neuroinflammation and Network Anomalies in Drug-Resistant Epilepsy 被引量:1
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作者 Jianwei Shi Jing Xie +4 位作者 Zesheng Li Xiaosong He Penghu Wei Josemir W Sander Guoguang Zhao 《Neuroscience Bulletin》 2025年第5期881-905,共25页
Epilepsy affects over 50 million people worldwide.Drug-resistant epilepsy(DRE)accounts for up to a third of these cases,and neuro-inflammation is thought to play a role in such cases.Despite being a long-debated issue... Epilepsy affects over 50 million people worldwide.Drug-resistant epilepsy(DRE)accounts for up to a third of these cases,and neuro-inflammation is thought to play a role in such cases.Despite being a long-debated issue in the field of DRE,the mechanisms underlying neuroinflammation have yet to be fully elucidated.The pro-inflammatory microenvironment within the brain tissue of people with DRE has been probed using single-cell multimodal transcriptomics.Evidence suggests that inflammatory cells and pro-inflammatory cytokines in the nervous system can lead to extensive biochemical changes,such as connexin hemichannel excitability and disruption of neurotransmitter homeostasis.The presence of inflammation may give rise to neuronal network abnormalities that suppress endogenous antiepileptic systems.We focus on the role of neuroinflammation and brain network anomalies in DRE from multiple perspectives to identify critical points for clinical application.We hope to provide an insightful overview to advance the quest for better DRE treatments. 展开更多
关键词 NEUROGLIA Neuro-immune interaction Brain network CHRONICITY EPILEPSY
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Methods for separating the noise produced by the wheels and track during a train pass‑by
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作者 David Thompson Dong Zhao +4 位作者 Giacomo Squicciarini Martin Toward Ester Cierco Erwin Jansen Michael Dittrich 《Railway Engineering Science》 2025年第3期342-358,共17页
Rolling noise is produced by vibration of the wheels and track,induced by their combined surface roughness.It is important to know the relative contributions of the different sources,as this affects noise control stra... Rolling noise is produced by vibration of the wheels and track,induced by their combined surface roughness.It is important to know the relative contributions of the different sources,as this affects noise control strategies as well as acceptance testing of new rolling stock.Three different techniques are described that aim to use pass-by measurements to separate the wheel and track components of rolling noise.One is based on the TWINS model,which is tuned to measured track vibration.The second is based on the advanced transfer path analysis method,which provides an entirely experimental assessment.The third is based on the pass-by analysis method in combination with static vibroacoustic transfer functions which are obtained using a reciprocity method.The development of these methods is described and comparisons between them are presented using the results from three experimental measurement campaigns.These covered a metro train,a regional train and a high-speed train at a range of speeds.The various methods agree reasonably well in terms of overall trends,with moderate agreement in the mid-frequency region,and less consistent results at low and high frequency. 展开更多
关键词 Railway noise Rolling noise Source separation Pass-by tests
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A two-scale framework for mapping site productivity of Eucalyptus globulus Labill.plantations in northern Spain in the context of climate change and using spatially explicit environmental variables as predictors
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作者 Iyan Teijido-Murias Carlos A.Lopez-Sanchez +4 位作者 Pilar Garcia-Manteca Juan Daniel Garcia Villabrille Alberto Rojo-Alboreca Federico Ruiz Marcos Barrio-Anta 《Forest Ecosystems》 2025年第5期877-893,共17页
This research aimed to obtain accurate estimates of the productivity of eucalyptus plantations under different climate change scenarios without the need for additional fieldwork.Thus,we used tree growth data from 1,10... This research aimed to obtain accurate estimates of the productivity of eucalyptus plantations under different climate change scenarios without the need for additional fieldwork.Thus,we used tree growth data from 1,102research plots,existing spatially continuous environmental data,and the random forest(RF) algorithm to construct raster-based models.We constructed models to predict site index(SI) at landscape scale(250m·pixel^(-1)),which is useful for planning purposes and for analyzing the effect of climate change on productivity,and at forest plot scale(resolutions of 10,25,50,and 100 m-pixel^(-1)),which is essential for predicting plantation yields.All models explained~50% of site index variability,as is usual in this type of study.We found that the different spatial resolutions of predictor variables did not affect the amount of variability explained.This finding may be due to two opposing effects on the explained variability at finer scales:a positive effect,as finer scales enable capture of microscale landform variability through a high-resolution digital elevation model(DEM),and a negative effect due to the introduction of "noise" when downscaling the climatic and lithological information from coarser scales.Elevation and the climatic variables(mainly temperature) were the most important predictor variables:For every 100 m-increase in elevation,the productivity decreased by on average 0.3-0.9 m of site index(1-1.3 m^(3)·ha^(-1)·year^(-1) of maximum mean annual increment in volume) and for each degree-Celsiusincrease in annual mean temperature,productivity increased by about 2.2 m in site index(3 m^(3)·ha^(-1)·year^(-1)of maximum mean annual increment in volume).Due to the forecasted increase in temperatures under climate change,productivity is expected to increase significantly in Eucalyptus globulus plantations in northern Spain in the coming decades,by between 1.68% and 3.38% of the current average site index under the most pessimistic climate change scenario and between 1.79% and 2.48% of the current average site index for the moderate scenario.We conclude that currently available spatially continuous environmental data can be used to develop accurate raster data models for predicting site productivity for E.globulus without the need for fieldwork.The spatially explicit maps produced in the study provide support to forest planners,forest managers,private landowners and politicians,enabling well-founded decisions to be made regarding selection of the best sites for afforestation and providing accurate yield predictions for the plantations. 展开更多
关键词 Tasmanian blue gum Site quality Site index(SI) Spatial resolution Random forest(RF) Climate change
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拘禁球囊技术在冠状动脉分叉病变中应用的临床疗效观察 被引量:16
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作者 金国珍 王军 +3 位作者 刘志忠 单守杰 张俊杰 陈绍良 《中国心血管杂志》 2017年第6期428-432,共5页
目的总结拘禁球囊技术治疗冠状动脉分叉病变的经验,并分析其安全性和疗效。方法选择2014年6月至2016年4月在南京医科大学附属南京医院行冠状动脉造影证实为真性分叉病变的患者50例,按随机数字表法分为两组:拘禁导丝组(25例)和拘禁球囊组... 目的总结拘禁球囊技术治疗冠状动脉分叉病变的经验,并分析其安全性和疗效。方法选择2014年6月至2016年4月在南京医科大学附属南京医院行冠状动脉造影证实为真性分叉病变的患者50例,按随机数字表法分为两组:拘禁导丝组(25例)和拘禁球囊组(25例),比较两组患者分支夹层或闭塞发生率、置入支架数量、手术时间和造影剂用量等,并对主要不良心血管事件(MACE)、病变血管再狭窄情况进行随访,对其有效性和安全性进行评价。结果拘禁导丝组4例发生分支闭塞或夹层,共置入5枚支架,拘禁球囊组1例发生分支夹层,置入1枚支架,且拘禁导丝组的手术时间和造影剂用量均明显高于拘禁球囊组,差异有统计学意义[(84.5±13.4)min比(53.2±9.8)min,t=2.84,P=0.009;(135.3±12.5)ml比(106.8±11.7)ml,t=8.33,P=0.001]。术后1年,复查冠状动脉造影并行冠状动脉造影定量分析检查,两组主支和边支血管管腔丢失差异均无统计学意义(均为P>0.05)。随访期间,拘禁球囊组有1例患者因心力衰竭发作入院,拘禁导丝组有1例患者因心绞痛再发入院,并行靶血管血运重建治疗,余无其他MACE事件。结论拘禁球囊技术是一种治疗冠状动脉分叉病变的有效方法,与传统保护导丝比较,拘禁球囊技术能够有效防止重要分支闭塞,且手术时间和曝光时间短、造影剂用量少,是一种安全、可行的方法。 展开更多
关键词 冠状动脉疾病 分叉病变 血管成形术 经腔 经皮冠状动脉 拘禁球囊技术
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中国古代家风建设之道及其现代价值 被引量:4
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作者 赵伟 张妍 《河北师范大学学报(教育科学版)》 CSSCI 北大核心 2018年第5期41-47,共7页
家庭是社会的细胞,是培育社会主义建设者与创新人才的重要场所和基本阵地。中国古代家风是中华优秀传统文化的一部分,是中华民族的文化血脉,是中华民族的精神家园。在中国古代家风建设当中,积极践行和倡导的孝悌为本的忠孝之道、诚信做... 家庭是社会的细胞,是培育社会主义建设者与创新人才的重要场所和基本阵地。中国古代家风是中华优秀传统文化的一部分,是中华民族的文化血脉,是中华民族的精神家园。在中国古代家风建设当中,积极践行和倡导的孝悌为本的忠孝之道、诚信做人的为人之道、勤俭节约的治家之道、崇德向善的修身之道、砥砺志向的教子之道、公正廉洁的为官之道、谨言慎行的处世之道等,是中国古代家风建设的基本内容和要求。这些优秀的中华民族家风传统,对当今家庭教育子女、纠正家庭教育中的一些偏差和失误,建设和谐家庭、和谐社会有着重要的借鉴意义。 展开更多
关键词 中华优秀传统文化 家风 建设之道 现代价值
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将Sclerostin的中文名词统一为硬骨抑素的建议 被引量:1
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作者 夏维波 李梅 +1 位作者 章振林 柯华珠 《中华骨质疏松和骨矿盐疾病杂志》 CSCD 北大核心 2019年第3期211-212,共2页
2019年4月9日安进/UCB公司宣布美国食品药品监督管理局(Food and Drug Adminisration,FDA)批准Sclerostin单克隆抗体Evenity (Romosozumab)上市,用于治疗绝经后女性伴高骨折风险的骨质疏松症。Evenity成为全球首个获批上市的抗Sclerosti... 2019年4月9日安进/UCB公司宣布美国食品药品监督管理局(Food and Drug Adminisration,FDA)批准Sclerostin单克隆抗体Evenity (Romosozumab)上市,用于治疗绝经后女性伴高骨折风险的骨质疏松症。Evenity成为全球首个获批上市的抗Sclerostin单克隆抗体药物,既能促进骨形成,又能减少骨吸收。该药的上市将对未来骨质疏松症的治疗模式带来深远影响。 展开更多
关键词 骨质疏松症 美国食品药品监督管理局 单克隆抗体药物 抑素 名词 中文 绝经后女性 DRUG
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Are assemblages of the fireworm Hermodice carunculata enhanced in sediments beneath offshore fish cages?
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作者 Rodrigo Riera Oscar Pérez +2 位作者 Myriam Rodríguez Eva Ramos óscar Monterroso 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第4期108-111,共4页
Abundances of the fireworm Hermodice carunculata were counted through a monitoring assessment study of fish cages in Barranco Hondo(NE Tenerife). Seven campaigns were conducted from November 2007 to June 2010 and te... Abundances of the fireworm Hermodice carunculata were counted through a monitoring assessment study of fish cages in Barranco Hondo(NE Tenerife). Seven campaigns were conducted from November 2007 to June 2010 and temporal variations were found, as well as differences among sampling stations. The polychaete H. carunculata obtained its highest abundance in sediments beneath fish cages throughout the study period. Thus, the assemblages of this omnivorous species were favoured by the presence of fish cages. 展开更多
关键词 aquaculture organic enrichment environmental impact POLYCHAETA Hermodice carunculata TENERIFE Canary Islands Atlantic Ocean
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Molecular epidemiology and putative origin of hepatitis C virus in random volunteers from Argentina 被引量:1
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作者 Noemí del Pino José Raúl Oubia +11 位作者 Francisco Rodríguez-Frías Juan Ignacio Esteban María Buti Teresa Otero Josep Gregori Damir García-Cehic Silvia Camos María Cubero Rosario Casillas Jaume Guàrdia Rafael Esteban Josep Quer 《World Journal of Gastroenterology》 SCIE CAS 2013年第35期5813-5827,共15页
AIM:To study the subtype prevalence and the phylogenetic relatedness of hepatitis C virus(HCV)sequences obtained from the Argentine general population,a large cohort of individuals was analyzed.METHODS:Healthy Argenti... AIM:To study the subtype prevalence and the phylogenetic relatedness of hepatitis C virus(HCV)sequences obtained from the Argentine general population,a large cohort of individuals was analyzed.METHODS:Healthy Argentinian volunteers(n=6251)from 12 provinces representing all geographical regions of the country were studied.All parents or legal guardians of individuals younger than 18 years provided informed written consent for participation.The corresponding written permission from all municipal authorities was obtained from each city or town where subjects were to be included.HCV RNA reverse transcription-polymerase chain reaction products were sequenced and phylogenetically analyzed.The 5’untranslated region(5’UTR)was used for RNA detection and initial genotype classification.The NS5B polymerase region,encompassing nt 8262-8610,was used for subtyping.RESULTS:An unexpectedly low prevalence of HCV infection in the general population(0.32%)was observed.Our data contrasted with previous studies that reported rates ranging from 1.5%to 2.5%,mainly performed in selected populations of blood donors or vulnerable groups.The latter values are in keeping with the prevalence reported by the 2007 Argentinian HCV Consensus(approximately 2%).HCV subtypes weredistributed as follows:1a(25%),1b(25%),2c(25%),3a(5%),and 2j(5%).Two isolates ascribed either to genotype 1(5%)or to genotype 3(5%)by 5’UTR phylogenetic analysis could not be subtyped.Subtype 1a sequences comprised a highly homogeneous population and clustered with United States sequences.Genotype1b sequences represented a heterogeneous population,suggesting that this genotype might have been introduced from different sources.Most subtype 2c sequences clustered close to the 2c reported from Italy and Southern France.CONCLUSION:HCV has a low prevalence of 0.32%in the studied general population of Argentina.The pattern of HCV introduction and transmission in Argentina appears to be a consequence of multiple events and different for each subtype. 展开更多
关键词 HEPATITIS C VIRUS NS5B SUBTYPING Molecular epidemiology HEPATITIS C VIRUS ARGENTINA HEPATITIS C VIRUS 5’ untranslated region
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Ground Penetrating Radar Survey for the Location and Assessment of the Hydrocarbon Plumes at Gas Station Installations
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作者 Jose Vicente Fuente Rubén Diego Roberto Fabregad 《Journal of Geoscience and Environment Protection》 2021年第12期57-71,共15页
The present paper describes the implementation of GPR 3D survey for detecting and delineating possible remain<span style="font-family:"">s</span><span style="font-family:""... The present paper describes the implementation of GPR 3D survey for detecting and delineating possible remain<span style="font-family:"">s</span><span style="font-family:""> of hydrocarbon plumes on a gas station. The 3D-imaging was used for the detection of anomalous zones that were analyzed with some relevant signal attributes extracted by digital signal processing. These signal attributes or parameters ha</span><span style="font-family:"">ve</span><span style="font-family:""> been the frequency of the maximum energy concentration on time-frequency distribution and instantaneous amplitude that could be related </span><span style="font-family:"">to</span><span style="font-family:""> the local response of the electromagnetic interaction and the presence of hydrocarbon plumes or soil contaminated area</span><span style="font-family:"">s</span><span style="font-family:"">. The implementation methodology took place at a gas station monitored with a piezometric sensor installation with soil layer information. The 3D-imaging of processed data and its slicing tool permits visualizing expected targets as pipes, tanks and installations in the subsoil exposing the anomalous zones for refined analyses. This further processing has used some spectral attributes of the signal to assess the real presence of the total petroleum hydrocarbons (TPH) providing a new effort to simplify and overcome the current state of the geophysical methods able to assess the presence of hydrocarbon plumes </span><span style="font-family:"">in</span><span style="font-family:""> industrial environments regarding the time cost of the survey and the traceable indication of the spectral shi</span><span style="font-family:"">ft</span><span style="font-family:"">ment shown in the plume volume.</span> 展开更多
关键词 GPR Survey Time-Frequency Analysis Instantaneous Amplitude Slice Tomography 3D-Reconstruction Gas Station
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Confounding response of macrofauna from a confluence of impacts: brine and sewage pollution
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作者 Rodrigo Riera Fernando Tuya +2 位作者 Myriam Rodríguez óscar Monterroso Eva Ramos 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第10期74-81,共8页
Throughout the shores of the world, a confluence of different sources of pollution is common, e.g., through outlets releasing brine, industrial, and domestic sewage. In this study, we assessed whether a combined dispo... Throughout the shores of the world, a confluence of different sources of pollution is common, e.g., through outlets releasing brine, industrial, and domestic sewage. In this study, we assessed whether a combined disposal of domestic sewage and brine altered the patterns of abundance and assemblage structure of sub- tidal macrofauna inhabiting sandy seabeds on the south coast of Gran Canaria (Canary Islands, NE Atlantic Ocean). Samples were collected in two surveys (May 2008 and January 2009) at three distances (0, 15, and 30 m) away from the discharge point. Macrofaunal abundances showed different patterns with varying proximity from the disposal point in the two surveys. In May 2008, lower abundances were observed at 0 m (53.89±46.82 ind.) than at 15 m (120±91.7 ind.) and 30 m (283.89±189.33 ind.) away from the dis- posal point. In January 2009, however, higher abundances were observed at 0 m (131.33±58.69 ind.) than at 30 m (100±24.44 ind.) and 15 m (84.78±58.39 ind.) away from the disposal point. Significant differ- ences in macrofaunal assemblage structure were found with varying proximity from the discharge point in both surveys. The effect of proximity from the disposal point was confounded by changes in sedimen- tary composition between surveys, which contributed to explain differences in macrofaunal abundances and assemblage structure with varying proximity from the discharge point. As a result, confounding driver- s of macrofaunal assemblage structure, here, changes in sediment composition, accounted for changes in macrofaunal abundances and assemblage structure with varying proximity from a combined disposal point of brine and sewage. 展开更多
关键词 MACROFAUNA AMPHIPODA POLYCHAETA BRINE sewage Canary Islands
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