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环境科学学报 2023年第9期43卷 346-356页

作者：何泽琴李亚飞李俊张松林陈明 b.larry Li 重庆交通大学重庆400074 中国科学院重庆绿色智能技术研究院重庆400714 中国科学院大学重庆学院重庆400714 Ecological Complexity and Modeling Laboratory University of CaliforniaRiversideCA 92521-0124USA

铜(Cu)是三峡水库蓄水后消落带土壤中的典型重金属,揭示其迁移转化过程对三峡水库水环境保护具有重要意义.为探究微塑料(Microplastics,MPs)对三峡水库缓流区消落带土壤Cu迁移转化过程的影响,本试验以水动力条件弱为背景进行室内水位变... 详细信息

铜(Cu)是三峡水库蓄水后消落带土壤中的典型重金属,揭示其迁移转化过程对三峡水库水环境保护具有重要意义.为探究微塑料(Microplastics,MPs)对三峡水库缓流区消落带土壤Cu迁移转化过程的影响,本试验以水动力条件弱为背景进行室内水位变化淹水实验,分析了高密度聚乙烯(HDPE)和聚对苯二甲酸乙二醇酯(PET)两种典型MPs对三峡水库缓流区消落带土壤Cu形态的影响,同时结合紫外-可见吸收光谱分析了MPs影响下土壤溶解性有机质(Dissolved Organic Matter,DOM)与土壤Cu形态的关系.结果表明,两种MPs的添加均能导致土壤中残渣态和铁锰氧化物结合态Cu含量的降低及有机结合态Cu含量的增加,且分别能同时增加和降低土壤中可交换态和碳酸盐结合态Cu含量,最终表现为土壤中Cu总量降低.相关性分析结果显示,MPs存在情况下,土壤DOM特性如DOC含量、CDOM浓度(α(355))、芳香性(SUVA_(254))、疏水性(SUVA_(260))、分子量(E2/E3)及来源组分(E2/E4、E3/E4)与土壤Cu形态及总量均具显著相关关系.结果为阐明在MPs和水库水位变化共同作用下三峡水库消落带Cu的环境行为提供了科学基础.

关键词：微塑料(MPs) 土壤缓流区消落带三峡水库 Cu赋存形态溶解性有机质(DOM)

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生物入侵模型研究进展

科技导报 2011年第10期29卷 71-79页

作者：王勤龙李百炼长江大学信息与数学学院湖北荆州434023 加利福利亚大学河滨分校生态复杂性模型实验室美国加州河滨92521—0124

生物入侵的机制与控制已经成为生态学关注的重点和研究的热点问题。建立数学模型是解释生物入侵机制的主要手段,对外来生物包括疾病的入侵扩散过程进行模型分析不仅具有重要的理论意义,还有助于风险评估,特别对入侵进行早期预测、控制... 详细信息

生物入侵的机制与控制已经成为生态学关注的重点和研究的热点问题。建立数学模型是解释生物入侵机制的主要手段,对外来生物包括疾病的入侵扩散过程进行模型分析不仅具有重要的理论意义,还有助于风险评估,特别对入侵进行早期预测、控制、科学管理与防治。然而,目前有关生物入侵的数理模型方法还远不能满足实际的需要,本文系统地介绍和分析了生物入侵模型的研究现状。首先分析了对于生物入侵过程建模所要考虑的基本问题;然后讨论了几类典型的入侵数学模型,分析了各自的特点及条件,同时给出了有代表性的实例和最近的研究成果;其次比较列出了入侵模型分析的各类方法;最后探讨了生物入侵建模与求解过程中尚待解决的问题,并对未来研究进行了展望。

关键词：生物入侵数学模型扩散速度动力学复杂性行波精确解

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用水溶缓蚀剂进行深气井间歇处理

石油石化节能与计量 1987年第2期 61-63页

作者： James L Houk larry b.bufkin 陈瑜

深气井的间歇处理是西得克萨斯地区实行的腐蚀控制方法。被处理的井大部分用的是含烃类溶剂的油溶水散缓蚀剂。有些井用了水溶缓蚀,这可能是一种有效的处理方法。

关键词：缓蚀剂膜间歇处理气井水溶

Contemporary meta-analysis of short-term probiotic consumption on gastrointestinal transit

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World Journal of Gastroenterology 2016年第21期22卷 5122-5131页

作者： larry E Miller Angela K Zimmermann Arthur C Ouwehand Miller Scientific Consulting Inc. Asheville NC 28803 United States DuPont Nutrition and Health FIN-02460 Kantvik Finland

AIM: To determine the efficacy of probiotic supplementation on intestinal transit time(ITT) in adults and to identify factors that influence these outcomes. METHODS: We conducted a systematic review of randomized controlled trials of probiotic supplementation that measured ITT in adults. Study quality was assessed using the Jadad scale. A random effects meta-analysis was performed with standardized mean difference(SMD) of ITT between probiotic and control groups as the primary outcome. Meta-regression and subgroup analyses examined the impact of moderator variables on SMD of ***: A total of 15 clinical trials with 17 treatment effects representing 675 subjects were included in this analysis. Probiotic supplementation was moderately efficacious in decreasing ITT compared to control, with an SMD of 0.38(95%CI: 0.23-0.53, P bgroup analyses demonstrated statistically greater reductions in ITT with probiotics in subjects with vs without constipation(SMD: 0.57 vs 0.22, P bjects(R^2 = 26%, P = 0.02), and fewer probiotic strains(R^2 = 20%, P biotics in meta-regression. Medium to large treatment effects were identified with b. lactis HN019(SMD: 0.67, P b. lactis DN-173 010(SMD: 0.54, P biotic strains yielded negligible reductions in ITT relative to ***: Probiotic supplementation is moderately efficacious for reducing ITT in adults. Probiotics were most efficacious in constipated subjects, when evaluated in high-quality studies, and with certain probiotic strains.

关键词： Constipation Gastrointestinal Intestinal transit time Meta-analysis Probiotics

A Cohort Model for Ash Mortality Risk Due to Potential Emerald Ash borer Infestation

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Open Journal of biophysics 2016年第2期6卷 38-51页

作者： Samuel G. Jenkins Peter G. Oduor larry Kotchman Michael Kangas GIS Coordinator Moorhead Public Service Moorhead MN USA Department of Geosciences North Dakota State University Fargo ND USA State Forester North Dakota Forest Service Bottineau ND USA Nursery & State Forest Team Leader North Dakota State University Fargo ND USA

Emerald ash borer (Agrilus planipennis Fairmaire) (Coleoptera: buprestidae) is a phloem-feeding beetle native to Asia that is causing widespread mortality of ash trees in eastern North America. In this study, we quantify ash mortality risk associated with potential anthropogenic-induced introduction of Emerald Ash borer (EAb) in North Dakota. The cohort model is calibrated with data from Ohio using weighting across factors—proximity to existing ash stands, campgrounds, roads and rails—to get a more accurate assessment of overall ash mortality risk. These factors are known to be associated with introduction of EAb to unaffected areas. Two protocols, a) “detection trees” and b) EAb traps are utilized to investigate EAb presence. Ash mortality risk maps such as the ones produced here may guide the placement of traps. Although North Dakota regions of high density ash tree stands are few, the resulting relative ash mortality risk map displays: a) very high risk areas around the Turtle Mountains and Theodore Roosevelt National Park and b) regions of high relative risk along the main riparian corridors. The applicability of risk maps such as the one developed may aid in assessing areas that may require significant monitoring.

关键词： Exposure Pathway Relative Risk EAb Risk Model

Approaching democracy / larry berman, bruce Allen Murphy. 5th ed.

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Systemic Effects of Growth Hormone in Growth Hormone Deficient Adults: A Meta-Analysis of 48 Prospective Studies

2007年

作者： larry berman bruce Allen Murphy.

来源：畅想之星图书光盘版（南... 评论

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Open Journal of Urology 2012年第3期2卷 87-103页

作者： Alexander W. Pastuszak Win Shun Lai Mohit Khera larry I. Lipshultz Scott Department of Urology Baylor College of Medicine Houston USA

Introduction: The use of growth hormone (GH) treatment in GH deficiency (GHD) continues to increase. However, individual controlled trials of the efficacy and safety of GH have involved relatively few patients and yielded variable results. We seek to analyze the overall effect of GH treatment on various parameters by performing a contemporary meta-analysis of the efficacy and safety of GH administration. Methods: Meta-analysis of 48 blinded, placebo controlled, randomized clinical studies of GH treatment in GHD adults published up to June 2011 was performed. Analyzed variables included anthropomorphic measurements (waist-hip ratio (WHR), lean body mass (LbM)/fat free mass (FFM), trunk fat (TrF), total body water (TbW), fat mass (FM), and body mass index (bMI));cardiovascular (CV) parameters (systolic/diastolic blood pressure (SbP, DbP), heart rate (HR), stroke volume (SV), LDL, HDL, total cholesterol (TChol), triglycerides (TG), apolipoprotein b (Apob), C-reactive protein (CRP));and diabetes parameters (fasting insulin and glucose, hemoglobin A1c (HgbA1c)). Effect sizes (ES) were used to determine significance and weighted mean differences between GH and control were used to quantify size of effect. Results: 2231 adults with growth hormone deficiency were included. Significant beneficial changes resulting from GH administration were observed in the following variables: anthropomorphic—WHR, FM, LbM, FFM, TbW;cardiovascular—LDL, HDL, TChol, Apob, CRP;significant adverse changes were seen in diabetic parameters—fasting insulin, fasting glucose, and HgbA1c. Compared to prior meta-analyses, larger ESs were observed for LDL, HDL, total cholesterol, fasting insulin and fasting glucose levels. Conclusions: GH administration in GHD adults results in improvement in anthropomorphic parameters, as well as CV parameters, but with worsening of diabetes markers. Data on long-term safety, including on CV effects and malignancy, as well as data assessing the role of GH replacement i

关键词： Growth Hormone Growth Hormone Deficiency Meta-Analysis Sex Steroids

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该患者是否患有脑卒中？

美国医学会杂志（中文版） 2006年第4期25卷 231-242页

作者： larry b. Goldstein David L. Simel 陈霞（译）李舜伟（校） Department of Medicine （Neurology） Duke Center for Cerebrovascular Disease Center for Clinical Health Policy Research and Education Duke University and Department of Veterans Affairs Medical Center Department of Medicine Duke University Durham NC 不详

背景：为了进行适当的紧急治疗并采取相应的二级预防干预措施，怀疑脑卒中或短暂性脑缺血发作的患者需要接受准确的临床评估。目的：对1994年评估可疑脑卒中或短暂性脑缺血发作患者的临床症状和神经系统检查发现的准确性及可靠性的系统... 详细信息

背景：为了进行适当的紧急治疗并采取相应的二级预防干预措施，怀疑脑卒中或短暂性脑缺血发作的患者需要接受准确的临床评估。目的：对1994年评估可疑脑卒中或短暂性脑缺血发作患者的临床症状和神经系统检查发现的准确性及可靠性的系统综述进行更新、修订。资料来源：我们采用多种检索方法在MEDLINE数据库中搜索了1994—2005年发表的相关论著、综述以及私人藏书中的教科书目录。研究选择：所选文章需具备主要数据，或者对病史或体格检查的准确性和／或可靠性进行了适当的总结性统计分析。这些资料均与伴有神经系统体征的患者的诊断或短期预后相关，临床往往据此考虑脑卒中的诊断。阐述准确性的文章还需提供在神经影像学和全部相关实验室检查后得出的最终诊断。资料提取：作者审读并摘录评估敏感性、特异性以及阳性及阴性似然比（1ikelihood ratios，LRs）的相关材料。可靠性评估则基于报告的kappa（k）统计值或者适用的组内相关系数。资料汇总：在有神经系统相关症状的患者中，发生脑卒中的先验概率（prior probabitity）为10％。在应用现代神经影像技术进行的研究中，急性面瘫、上肢无力或言语异常的出现均使脑卒中的可能性增加（≥1个发现的LR：5．5；95％CI，3．3—9．1），而缺乏上述症状则降低脑卒中的可能性（阴性发现的LR=0．39；95％CI，0．25—0．61）。准确确定脑卒中亚型需要神经影像学技术，主要是鉴别缺血性脑卒中和出血性脑卒中。出现意识障碍、偏瘫和协调性凝视麻痹任一组合的患者早期死亡率增加（≥1个发现的LR=1．8；95％CI，1．2—2．8；0发现的LR：0．36；95％CI，0．13—1．0）。与没有血管性事件相比，高度支持脑卒中或短暂性脑缺血发作诊断的症状是：突然出现语言能力变化、视力丧失、复视、麻木或麻刺感、肢体瘫痪或无力以及与体位变化无关的头晕（k=0．60；95％CI，0．52—0．68）。神经系统检查发现的可靠性在稍准确至几乎完全准确之间，但采用国立卫生研究院卒中量表等标准评分系统可以提高其可靠性。根据检查所见确定卒中的血管分布，其可靠性在中度至良好之间（K=0．54；95％CI，0．39．0．68）。结论：对于可能有脑卒中的患者而言，病史和临床检查不但是进行评估的基础，也是选择适当治疗方案的基础。强调3个临床发现（突然出现面瘫、上肢无力或言语异常）的意义可以提高诊断的准确性和可靠性。

关键词：出血性脑卒中患者短暂性脑缺血发作 MEDLINE数据库神经系统检查神经影像学技术国立卫生研究院临床症状神经系统体征组内相关系数

A TEM Study of Cobalt-base Alloy Prototypes Fabricated by EbM

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Materials Sciences and Applications 2011年第5期2卷 355-363页

作者： Sara M. Gaytan larry E. Murr Diana A. Ramirez brenda I. Machado Edwin Martinez Daniel H. Hernandez Jose L. Martinez Francisco Medina Ryan b. Wicker 不详

A novel microstructural architecture consisting of Cr23C6 carbide spatial columns was created in solid components of Co-26Cr-6Mo-0.2C fabricated from powder by additive manufacturing using electron beam melting. These columns of carbides extended in the build direction and are formed by the x-y rastering of the electron beam to pre-heat and melt powder layers using CAD models. These microstructural architectures are similar to rapidly solidified/unidirectionally solidified structures created by heat extraction in the direction perpendicular to the build plane. These columnar carbide architectures were observed by optical metallography and transmission electron microscopy (TEM) and compared with intrinsic stacking fault microstructures observed in annealed components. The TEM analysis allowed the details of the carbide crystal structure and corresponding cubic morphology to be observed.

关键词： Electron beam Melting Stacking Faults Precipitates