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Lineaperpetua gen.nov.:a new diatom genus in the Thalassiosirales supported by morphology and molecular data
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作者 Pan YU Lin YANG +4 位作者 Qingmin YOU John Patrick KOCIOLEK Kangyu WANG Yonghong BI Quanxi WANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期277-290,共14页
Based on a combination of morphology and molecular data of ribosomal DNA genes,a new diatom genus Lineaperpetua gen.nov.Yu,You,Kociolek&Wang is described.The features that help define Lineaperpetua at the level of... Based on a combination of morphology and molecular data of ribosomal DNA genes,a new diatom genus Lineaperpetua gen.nov.Yu,You,Kociolek&Wang is described.The features that help define Lineaperpetua at the level of genus include:a tangentially undulated valve face;continuous cribra areolae on the valve interior consisting of pores arranged as strips;single rimoportula located inside the ring of marginal fultoportulae.Additionally,phylogenetic analysis based on nuclear small subunit(SSU)rDNA sequences and nuclear large subunit(LSU)rDNA gene placed the three strains of L.lacustris in a single,monophyletic clade at a considerable sequence distance from the other genera(Thalassiosira,Conticribra,Planktoniella,Shinodiscus,and other genera)belonging to Thalassiosirales.Despite the similarities with some species of Thalassiosira,Conticribra,and Spicaticribra,the suite of features found in Lineaperpetua differentiate it from these other genera.These molecular data and morphological characters suggest an affinity of the new genus to the Thalassiosiraceae. 展开更多
关键词 DIATOM MORPHOLOGY new genus PHYLOGENY TAXONOMY Thalassiosiraceae
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Two new Stephanodiscaceae species(Bacillariophyta)from SW China
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作者 Pan YU Fen LUO +4 位作者 Qingmin YOU John Patrick KOCIOLEK Wanting PANG Yue CAO Quanxi WANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第6期2024-2033,共10页
Two new freshwater centric diatom species were described from the southwest of China based on light and scanning electron microscopy.Pliocaenicus weixiense sp.nov.has a transversely undulate valve face,marginal fultop... Two new freshwater centric diatom species were described from the southwest of China based on light and scanning electron microscopy.Pliocaenicus weixiense sp.nov.has a transversely undulate valve face,marginal fultoportulae situated at the end of the hyaline strips,central fultoportulae forming a ring positioned in a circular pattern,each with 3-4(usually 3)satellite pores,and a single rimoportula located at the base of the inner distal end of the costa.Tertiarius aspera sp.nov.has an uneven valve face with small granules that may be present on the marginal area and valve mantle,marginal fultoportulae situated on each costa close to the margin of the valve,6-7 central fultoportulae forming a ring near the valve center each with two satellite pores,and one rimoportula located on the valve face/mantle junction in the middle of costa on the internal valve.T.aspera sp.nov.is the first reported extant species in the genus.This study played an important role in studying the taxonomic status and ecological information of the genus,and the establishment of the two new taxa will help demonstrate the unique nature of freshwater diatom flora in the southwest of China. 展开更多
关键词 DIATOM centric new species Pliocaenicus Tertiarius China
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Comparative Study of Probabilistic and Least-Squares Methods for Developing Predictive Models
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作者 Boribo Kikunda Philippe Thierry Nsabimana +2 位作者 Jules Raymond Kala Jeremie Ndikumagenge Longin Ndayisaba 《Open Journal of Applied Sciences》 2024年第7期1775-1787,共13页
This article explores the comparison between the probability method and the least squares method in the design of linear predictive models. It points out that these two approaches have distinct theoretical foundations... This article explores the comparison between the probability method and the least squares method in the design of linear predictive models. It points out that these two approaches have distinct theoretical foundations and can lead to varied or similar results in terms of precision and performance under certain assumptions. The article underlines the importance of comparing these two approaches to choose the one best suited to the context, available data and modeling objectives. 展开更多
关键词 Predictive Models Least Squares Bayesian Estimation Methods
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A robust protocol to compute wind load coefficients of telecommunication towers and antennas using numerical simulation for risk and resilience assessment
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作者 Mohanad Khazaali Liyang Ma +2 位作者 Keivan Rokneddin Matteo Mazzotti Paolo Bocchini 《Resilient Cities and Structures》 2024年第1期66-83,共18页
An accurate estimation of wind loads on telecommunication towers is crucial for design,as well as for perform-ing reliability,resilience,and risk assessments.In particular,drag coefficient and interference factor are ... An accurate estimation of wind loads on telecommunication towers is crucial for design,as well as for perform-ing reliability,resilience,and risk assessments.In particular,drag coefficient and interference factor are the most significant factors for wind load computations.Wind tunnel tests and computational fluid dynamics(CFD)are the most appropriate methods to estimate these parameters.While wind tunnel tests are generally preferred in practice,they require dedicated facilities and personnel,and can be expensive if multiple configurations of tower panels and antennas need to be tested under various wind directions(e.g.,fragility curve development for system resilience analysis).This paper provides a simple,robust,and easily accessible CFD protocol with widespread applicability,offering a practical solution in situations where wind tunnel testing is not feasible,such as complex tower configurations or cases where the cost of running experiments for all the tower-antennas configurations is prohibitively high.Different turbulence models,structural and fluid boundary conditions and mesh types are tested to provide a streamlined CFD modeling strategy that shows good convergence and balances accuracy,computational time,and robustness.The protocol is calibrated and validated with experimental studies available in the literature.To demonstrate the capabilities of the protocol,three lattice tower panels and antennas with different configurations are analyzed as examples.The protocol successfully estimates the drag and lateral wind loads and their coefficients under different wind directions.Noticeable differences are observed between the esti-mated wind loads with this protocol and those computed by a simple linear superposition used in most practical applications,indicating the importance of tower-antenna interaction.Also,as expected,the wind loads recom-mended by design codes overestimate the simulated results.More importantly,the telecommunication design codes inadequately identify the most favorable wind directions that are associated with the lowest wind loads,while the results of the proposed protocol align with observations from experimental studies.This information may be used to select the tower orientation before construction.The findings of this study are of importance for the telecommunication industry,which seeks reliable results with minimal computational efforts.In addition,it enhances the fragility analysis of telecommunication towers under strong winds,and the portfolio risk and resilience assessment of telecommunication systems. 展开更多
关键词 Generalized CFD protocol Lattice tower Tower panel Microwave antenna Wind coefficients Tower-antenna interaction
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在中国使用左乙拉西坦和卡马西平单药治疗部分性癫痫发作的比较:一项开放性、非劣效性试验的主要结果 被引量:9
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作者 廖卫平 周东 +4 位作者 Toru Osakabe Christian Loesch 杜新鲁 Frank Tennigkeit 王学峰 《临床神经病学杂志》 CAS 2020年第5期321-327,共7页
目的针对≥16岁、新诊断或最近诊断为部分性癫痫发作的中国患者,比较左乙拉西坦和速释卡马西平(CBZ-IR)单药治疗的疗效。方法在Ⅲ期、随机分配、开放性试验N01364(NCT01954121)中,患者按1∶1的比例随机分配接受左乙拉西坦1 000 mg/d或CB... 目的针对≥16岁、新诊断或最近诊断为部分性癫痫发作的中国患者,比较左乙拉西坦和速释卡马西平(CBZ-IR)单药治疗的疗效。方法在Ⅲ期、随机分配、开放性试验N01364(NCT01954121)中,患者按1∶1的比例随机分配接受左乙拉西坦1 000 mg/d或CBZ-IR 400 mg/d,记录6个月无癫痫发作的患者比例及患者保留率、首次癫痫发作的时间、因不良事件或缺乏疗效导致首次癫痫发作/中止试验的时间、安全性和耐受性。结果在对符合方案集进行的分析中,接受左乙拉西坦治疗的186例患者中有88例(47.3%),接受CBZ-IR治疗的171例患者中有117例(68.4%)达到6个月无癫痫发作;校正后绝对差值为-22.9%(95%CI:-33.1%,-12.6%),其下限低于非劣效性界值-20%。左乙拉西坦组的患者保留率为48.4%,CBZ-IR组为70.2%。对于评估期首次癫痫发作时间,左乙拉西坦与CBZ-IR的风险比为2.686(95%CI:1.838,3.927);对于因不良事件或缺乏疗效导致首次癫痫发作/中止试验的时间,风险比为2.338(95%CI:1.629, 3.356)。使用左乙拉西坦在治疗中出现的不良事件(61.9%)略低于CBZ-IR(67.9%)。结论在低剂量单药治疗下,无法确定左乙拉西坦的疗效不低于CBZ-IR。左乙拉西坦的安全性/耐受性情况优于CBZ-IR。 展开更多
关键词 卡马西平 疗效 部分性癫痫发作 左乙拉西坦 安全性/耐受性
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钠多普勒激光雷达回波光子数仿真及大气参数反演 被引量:12
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作者 徐丽 胡雄 +3 位作者 程永强 郭商勇 闫召爱 Xinzhao Chu 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2010年第7期1520-1528,共9页
钠多普勒激光雷达利用中层顶区域的钠原子作为示踪物,探测中层顶区域大气风场和温度剖面.本文主要分析钠多普勒激光雷达的探测原理和大气参数反演算法.利用MSISE和HWM93等大气模型给出背景大气温度、密度及风场,并给定钠原子数密度剖面... 钠多普勒激光雷达利用中层顶区域的钠原子作为示踪物,探测中层顶区域大气风场和温度剖面.本文主要分析钠多普勒激光雷达的探测原理和大气参数反演算法.利用MSISE和HWM93等大气模型给出背景大气温度、密度及风场,并给定钠原子数密度剖面,从激光雷达方程出发,模拟计算了激光雷达的瑞利散射和钠共振荧光散射回波光子数.利用模拟的回波光子数剖面数据,反演得到大气温度、视线风速和钠原子数密度剖面,反演结果与模拟计算用的背景参数符合很好,验证了这一反演方法的正确性.分析了激光频率偏移和激光线宽变化对反演精度的影响. 展开更多
关键词 钠多普勒激光雷达 回波光子数 温度和风场反演
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《饲料添加剂氯化胆碱中氯化胆碱的测定》新国家标准的研制 被引量:12
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作者 常碧影 宋荣 +1 位作者 丁永胜 廖志勇 《中国饲料》 北大核心 2002年第9期23-25,共3页
氯化胆碱(Choline Choride)化学名称为2-羟乙基-三甲基胺盐酸盐,是动物生长不可缺少的一种水溶性维生素,在动物体内起着极其重要的作用。它是构成卵磷脂和鞘磷脂(构成体内磷脂的70%-80%)以及乙酰胆碱的主要成分。
关键词 饲料 添加剂 氯化胆碱 测定 国家标准 中国
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基于C/S关系的实时系统构件交互规约 被引量:5
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作者 刘晓燕 张云生 +1 位作者 J-J.Schwarz 李俊昌 《计算机工程与应用》 CSCD 北大核心 2007年第17期104-107,110,共5页
给出了基于构件的实时多任务应用系统图形化设计软件的构件接口定义。为解决基于构件的分布式C/S关系的实时软件构件的重用及装配问题,提出了构件相互交互的文本描述语言语法语义规约,其主要刻画了分布式实时构件之间的交互协议及其实... 给出了基于构件的实时多任务应用系统图形化设计软件的构件接口定义。为解决基于构件的分布式C/S关系的实时软件构件的重用及装配问题,提出了构件相互交互的文本描述语言语法语义规约,其主要刻画了分布式实时构件之间的交互协议及其实时特性。 展开更多
关键词 实时构件 实时系统 接口设计 C/S关系 交互规约
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UML-RT到一个图形设计环境体系结构的映射 被引量:5
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作者 刘晓燕 张云生 +1 位作者 J-J.Schwarz 李俊昌 《计算机科学》 CSCD 北大核心 2006年第6期280-283,共4页
为解决把UML-RT建模模型平滑过渡到实时系统的图形化的软构件设计开发环境的设计模型,本文提出了从UML-RT的结构模型映射到该环境下的体系结构模型的高层设计的映射方法。首先介绍UML-RT结构建模的概念及笔者研制的设计环境,其次给出从U... 为解决把UML-RT建模模型平滑过渡到实时系统的图形化的软构件设计开发环境的设计模型,本文提出了从UML-RT的结构模型映射到该环境下的体系结构模型的高层设计的映射方法。首先介绍UML-RT结构建模的概念及笔者研制的设计环境,其次给出从UML-RT映射到该设计环境体系结构模型的具体方法、约束和限制。 展开更多
关键词 UML-RT 图形化建模 软件体系结构 映射方法
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实时系统构件非功能性接口语义规约 被引量:4
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作者 刘晓燕 张云生 +1 位作者 J-J.Schwarz 李俊昌 《计算机科学》 CSCD 北大核心 2007年第6期251-252,257,共3页
该文给出了基于构件的实时多任务应用系统图形化设计软件的具有分布式C/S关系实时构件的接口定义,主要论述实时构件非功能性接口模型,针对实时特性,提出构件的非功能性接口在时间性、调度性、合成性、同步、互斥以及资源设备控制方面的... 该文给出了基于构件的实时多任务应用系统图形化设计软件的具有分布式C/S关系实时构件的接口定义,主要论述实时构件非功能性接口模型,针对实时特性,提出构件的非功能性接口在时间性、调度性、合成性、同步、互斥以及资源设备控制方面的语义规约。 展开更多
关键词 实时系统 实时构件 接口设计 非功能性 语义规约
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UML-RT到一个实时多任务执行模型的转换 被引量:1
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作者 刘晓燕 字天文 +2 位作者 张云生 J-J.Schwarz 李俊昌 《计算机科学》 CSCD 北大核心 2007年第7期275-278,共4页
为解决把UML-RT行为建模模型平滑过渡到实时多任务系统的图形化软构件设计开发环境的过程设计模型中,本文提出了把UML-RT状态图行为模型转换到该环境下的执行模型的方法。首先介绍UML-RT状态图建模的概念及笔者研制的设计环境,其次给出... 为解决把UML-RT行为建模模型平滑过渡到实时多任务系统的图形化软构件设计开发环境的过程设计模型中,本文提出了把UML-RT状态图行为模型转换到该环境下的执行模型的方法。首先介绍UML-RT状态图建模的概念及笔者研制的设计环境,其次给出从UML-RT状态图转换到该设计环境可执行模型的具体方法,最后以一个实例说明了转换方法。 展开更多
关键词 UML-RT 实时系统 状态图 行为建模 执行模型 转换方法.
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Synchrotron radiation X-ray fluorescence analysis of Fe, Zn and Cu in mice brain associated with Parkinson's disease 被引量:3
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作者 田甜 张继超 +6 位作者 雷豪志 诸颖 施继晔 胡钧 黄庆 樊春海 孙艳红 《Nuclear Science and Techniques》 SCIE CAS CSCD 2015年第3期100-105,共6页
The contents and distributions of metal elements in the brain are closely related to neurodegenerative diseases.In this study, we examined Fe, Cu and Zn contents in the brain section associated with Parkinson‘s disea... The contents and distributions of metal elements in the brain are closely related to neurodegenerative diseases.In this study, we examined Fe, Cu and Zn contents in the brain section associated with Parkinson‘s disease(PD)using synchrotron radiation X-ray fluorescence(SRXRF). PD mouse model induced by 1-methyl-4-phenyl-1,2,3,6-terahydropyridine(MPTP) was used for the elemental analysis(e.g., Fe, Cu and Zn) in the substantia nigra pars compacta(SNpc) region of mice brain tissue samples. We found that mice in the MPTP group had higher contents of Fe, Cu and Zn in the SNpc than the control group. After treating the PD mice with rapamycin, the contents of Fe, Cu and Zn were reduced, the dopamine neurons and motor function were rescued correspondingly. The results prompted that the SRXRF provided an ideal method for tracing and analyzing the metal elements in the brain section to assess the pathological changes of PD model and the therapeutic effect of drugs. 展开更多
关键词 同步辐射X射线荧光分析 帕金森病 锌含量 鼠脑 低铁 神经退行性疾病 小鼠模型 Fe含量
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A chaotic neural network mimicking an olfactory system and its application on image recognition 被引量:1
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作者 Walter J. Freeman 《Journal of Bionic Engineering》 SCIE EI CSCD 2004年第3期191-198,共8页
Based on the research of a biological olfactory system, a novel chaotic neural network model - K set model has been es- tablished. This chaotic neural network not only simulates the real brain activity of an olfactor... Based on the research of a biological olfactory system, a novel chaotic neural network model - K set model has been es- tablished. This chaotic neural network not only simulates the real brain activity of an olfactory system, but also presents a novel chaotic concept for signal processing and pattern recognition. The characteristics of the K set models are investigated and show that a KIII model can be used for image pattern classification. 展开更多
关键词 olfactory system pattern recognition neural networks image classification
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基于格子波尔兹曼的机器人视觉特征点检测
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作者 王琰 朱跃敏 +1 位作者 Guy Courbebaisse 丁良宏 《科学技术与工程》 2011年第32期8045-8048,8054,共5页
针对Harris特征点检测算法中图像存在角点信息丢失的问题,提出基于格子波尔兹曼结合Harris算法的机器人视觉特征点检测方法。格子波尔兹曼具有并行操作的优点,可以保证机器人导航的实时性。通过格子波尔兹曼方法对图像进行预处理,然后使... 针对Harris特征点检测算法中图像存在角点信息丢失的问题,提出基于格子波尔兹曼结合Harris算法的机器人视觉特征点检测方法。格子波尔兹曼具有并行操作的优点,可以保证机器人导航的实时性。通过格子波尔兹曼方法对图像进行预处理,然后使用Harris算法,实现特征点的有效检测。实验结果表明,该方法更加准确地选择特征点,减少特征点数目的同时,提升了特征点的质量,完成了特征相对不明显的点的检测。 展开更多
关键词 格子波尔兹曼 HARRIS算法 机器人视觉 图像处理
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Pharmacokinetics and toxicology of therapeutic proteins:Advances and challenges 被引量:3
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作者 Yulia Vugmeyster Frank-Peter Theil +1 位作者 Leslie A Khawli Michael W Leach 《World Journal of Biological Chemistry》 CAS 2012年第4期73-92,共20页
Significant progress has been made in understanding pharmacokinetics (PK),pharmacodynamics (PD),as well as toxicity profiles of therapeutic proteins in animals and humans,which have been in commercial development for ... Significant progress has been made in understanding pharmacokinetics (PK),pharmacodynamics (PD),as well as toxicity profiles of therapeutic proteins in animals and humans,which have been in commercial development for more than three decades.However,in the PK arena,many fundamental questions remain to be resolved.Investigative and bioanalytical tools need to be established to improve the translation of PK data from animals to humans,and from in vitro assays to in vivo readouts,which would ultimately lead to a higher success rate in drug development.In toxicology,it is known,in general,what studies are needed to safely develop therapeutic proteins,and what studies do not provide relevant information.One of the major complicating factors in nonclinical and clinical programs for therapeutic proteins is the impact of immunogenicity.In this review,we will highlight the emerging science and technology,as well as the challenges around the pharmacokinetic-and safety-related issues in drug development of mAbs and other therapeutic proteins. 展开更多
关键词 PHARMACOKINETICS TOXICOLOGY Therapeutic proteins BIOTHERAPEUTICS MONOCLONAL ANTIBODIES
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Toluene degradation by a water/silicone oil mixture for the design of two phase partitioning bioreactors 被引量:3
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作者 Maxime Guillerm Annabelle Couvert +3 位作者 Abdeltif Amrane Edith Norrant Audrey Breton éric Dumont 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第10期1512-1518,共7页
Toluene degradation performances were studied in a 10 L Two-Phase Partitioning Bioreactor(TPPB).The liquid phase consisted of a mixture of water and PDMS 50(Poly Di Methyl Siloxane,i.e.silicone oil,viscosity of 46 m P... Toluene degradation performances were studied in a 10 L Two-Phase Partitioning Bioreactor(TPPB).The liquid phase consisted of a mixture of water and PDMS 50(Poly Di Methyl Siloxane,i.e.silicone oil,viscosity of 46 m Pa·s) in the volume ratio of 75%/25%.Two series of experiments were carried out:in the first,the reactor was sequentially supplied with toluene whereas in the second,toluene was continuously supplied.Activated sludge from the wastewater treatment plant of Beaurade(Rennes,France) was used at an initial concentration of 0.5 dry mass g·(mixture L)^(-1).The elimination capacity(EC) was investigated as well as the change in biomass concentration over time.Toluene biodegradation was very ef ficient(removal ef ficiency,RE=100%) for toluene flows ranging from 0.2 to 1.2 ml·h^(-1),corresponding to elimination capacities of up to 104 g·m^(-3)·h^(-1).For a toluene flow of 1.2 ml·h^(-1),the biomass concentration measured at the end of the experiment was 4.7 dry mass g·(mixture L)^(-1).The oxygen concentration in the liquid phase was clearly not a limiting factor in these operating conditions.Based on these results,an extrapolation leading to the design of a large-scale pilot TPPB can now be considered to study toluene degradation performances in industrial conditions. 展开更多
关键词 Degradation Toluene Silicone oil Multiphase reactor Biomass
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超重和肥胖者的血管内皮NAD(P)H氧化酶-p47^(phox)表达增加并有内皮氧化应激的证据 被引量:1
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作者 Silver A.E. Beske S.D. +2 位作者 Christou D.D. D.R. Seals 徐永城 《世界核心医学期刊文摘(心脏病学分册)》 2007年第7期36-37,共2页
背景:肥胖可改变一些分子的血管内皮细胞蛋白表达(VECPE),从而影响对动脉粥样硬化的易感性。方法和结果:研究对象为无其他临床疾病、肥胖程度不同的108例男女性受试者(体重指数18.4~36.7kg/m^2;总体脂肪5.8~55.0kg;腰围6... 背景:肥胖可改变一些分子的血管内皮细胞蛋白表达(VECPE),从而影响对动脉粥样硬化的易感性。方法和结果:研究对象为无其他临床疾病、肥胖程度不同的108例男女性受试者(体重指数18.4~36.7kg/m^2;总体脂肪5.8~55.0kg;腰围63.0~122.9em),用定量免疫荧光法检测其血管内皮细胞。所有3种肥胖状况的表达方式均与氧化酶亚单位NAD(P)H氧化酶-p47[部分相关系数(rpart)=0.22~0.24,所有P〈0.05]和抗氧化酶过氧化氢酶(rpart=0.71~0.75,所有P〈0.001)的VECPE呈正相关。 展开更多
关键词 NAD(P)H氧化酶 血管内皮细胞 肥胖者 氧化应激 证据 超重 动脉粥样硬化 部分相关系数
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Characterization of organic-rich mineral debris revealed by rapid glacier retreat, Indren Glacier, European Alps 被引量:1
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作者 FREPPAZ Michele WILLIAMS Mark W. +5 位作者 GABRIELI Jacopo GORRA Roberta MANIA Ilaria ASCHER-JENULL Judith EGLI Markus CELI Luisella 《Journal of Mountain Science》 SCIE CSCD 2021年第6期1521-1536,共16页
In the summer of 2003 and 2004, characterized by a rapid glacier retreat, a stony surface covered by well-structured organic-rich mineral debris was observed very close to the Indren glacier terminus(Monte Rosa Massif... In the summer of 2003 and 2004, characterized by a rapid glacier retreat, a stony surface covered by well-structured organic-rich mineral debris was observed very close to the Indren glacier terminus(Monte Rosa Massif, NW Italy, 3100 m ASL), on an area covered by the glacier tongue till the year before. The origin and type of this organicrich material were investigated, in order to detect their characteristics, potential sources and fate within the foreland system. The deposits were dated using Carbon-14 and analyzed for the chemical characteristics of the organic component, the elemental composition of the mineral fraction and presence of microbial markers. The material, granular and dark in color, had a total organic carbon(TOC) content ranging between 17.4 ± 0.39 and 28.1 ± 0.63 g kg^(-1) dry weight(dw), significantly higher than the surrounding glacial till(~ 1.4 g kg^(-1) dw), although only 0.33% of it was in water soluble form. Microbial carbon(C) and nitrogen(N) accounted for 10.6% and 3.13% of TOC and total N, respectively. Dissolved nitrogen(N), mainly present as ammonium, represented 2.40% of the total N. The low aromatic component and large presence of nitrogen(N)-derived compounds suggested that most of the organic carbon(OC) in these organic-rich mineral deposits was derived from microbial cells, although the high average radiocarbon age of about 2900 years may also point to the contribution of aeolian depositions of anthropogenic or natural origin. Elemental composition and the crustal enrichment factor of trace elements in the mineral fraction of the aggregates corroborated the hypothesis that most part of the accumulated material derived from ice meltwater. Some indicators of the colonization of these deposits by microbial communities were also reported, from the abundance of DNA and phylogenetic markers, to the presence of bacterial taxa commonly able to thrive in similar habitats. All these elements suggested that such kind of deposits may have a potential role as energy and nutrient sources in recently deglaciated areas, highlighting the necessity to better understand the processes underlying their formation and their evolution. 展开更多
关键词 Glacier foreland Dissolved organic carbon Organic matter q PCR Microbial community Trace elements
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A Stochastic Strategy for Optimizing the Cost of Systematic Screening of Some Diseases in a Situation of Insufficient Equipment
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作者 Lucien Zihindula Biguru 《Applied Mathematics》 2020年第12期1253-1274,共22页
In this work, we show that when there is insufficient equipment for detecting a disease whose prevalence is <em>t</em>% in a sub-population of size <em>N</em>, it is optimal to divide the <e... In this work, we show that when there is insufficient equipment for detecting a disease whose prevalence is <em>t</em>% in a sub-population of size <em>N</em>, it is optimal to divide the <em>N</em> samples into <em>n</em> groups of size r each and then, the value <img src="Edit_ce149849-3742-48fe-820b-02ccc0c92d83.bmp" alt="" /> allows systematic screening of all <em>N</em> individuals by performing less than <em>N</em> tests (In this expression, <img src="Edit_987eb236-a883-4894-ba2d-52bde5f35056.bmp" alt="" /> represents the floor function<sup>1</sup> of <em>x</em> ∈ R). Based on this result and on certain functions of the R software, we subsequently propose a probabilistic strategy capable of optimizing the screening tests under certain conditions. 展开更多
关键词 Stochastic Optimization Binomial Distribution Systematic Screening PREVALENCE R Software
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Band-pass filtered velocity statistics in decaying turbulent box
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作者 J.M.Lenoir S.Simoёns Jean-Noel Gence 《Theoretical & Applied Mechanics Letters》 CAS 2011年第4期40-44,共5页
For homogeneous isotropic turbulence study,the acquisition of band-pass filtered velocity increments(FVI) in a non-forced turbulent box is still a challenge both experimentally and numerically.Turbulence and associate... For homogeneous isotropic turbulence study,the acquisition of band-pass filtered velocity increments(FVI) in a non-forced turbulent box is still a challenge both experimentally and numerically.Turbulence and associated physical processes,at a given instant,are permanently contaminated by a forcing process which can seldom be universal.The situation tends to be the origin of intermittency and the non-Gaussian probability density distribution for acceleration and velocity gradients.To reveal implied mechanism,grid turbulence is adapted to observe non-perturbed homogeneous isotropic turbulence.The velocity increments(VI) can be obtained following Comte-Bellot and Corrsin(GCBC) by means of two point-two time shifted velocity measurements.It is difficult to obtain decaying turbulence(DT) at large turbulent Reynolds number without pollution coming from walls.Nevertheless it is also significant to investigate DT in low Reynolds number regimes to determine non-polluted tendencies.The similarity of DT between particle image velocimetry(PIV) and hot wire anemometry measurements by GCBC are presented.Here we focus our tendency on VI and FVI probability density function(PDF) shapes in this letter.In conclusion,the tendency to Gaussian shape in inertial zone wavenumbers,demonstrates that there will be no intermittency if turbulent cascade is not perturbed. 展开更多
关键词 velocity increment velocity inertial zone homogeneous turbulence PDF shape
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