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Regeneration status of riparian tree species in two sites that differ in land-use in the Okavango Delta,Botswana

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Journal of Forestry Research 2017年第5期28卷 1073-1082页

作者： Gaolathe Tsheboeng mike Murray-Hudson Keotshephile Kashe Okavango Research Institute

Human communities from the Okavango Delta benefit from the services and goods provided by the wetland ecosystem through its riparian vegetation. These include food and timber products used for the construction of shelter and canoes. Despite the importance of riparian tree species in the Delta, their regeneration structure is currently unknown. For riparian trees to be managed sustainably, information on the current regeneration status of the trees under different land uses is needed. The Moremi game reserve (protected area) and Seronga (communal area) were selected for this study on the regeneration of riparian tree species of Croton megalobotrys Müll. Arg, Philenoptera violacea (Klotzsch) Schrire, Senegalia nigrescens (Acacia nigrescens) Oliv and Diospyros mespiliformis Hochst. ex A. Dc. The height of each individual tree was estimated in randomly selected 30 plots (15 from each site) of 20 × 50 m for assignment to five regeneration classes: 0-0.5, 0.5-1, 1-2, 2-4 and >4 m. Linear regression was used to infer regeneration status of each species. An independent-sample Student’s t test was used to determine any significance differences in seedling density/ha and sapling density/ha between different sites at p < 0.05. Diospyros mespiliformis populations had an unstable regeneration structure in both sites, while P. violacea regeneration was stable regardless of land-use type. Croton megalobotrys and S. nigrescens had an unstable regeneration pattern in Seronga, while in Moremi it was stable; thus, the regeneration structure of C. megalobotrys and S. nigrescens is affected by land-use. This result implies that intervention is needed to conserve the two species in Seronga where the current land-use appears to be incompatible with regeneration; D. mespiliformis also needs to be conserved in both Moremi and Seronga.

关键词： Conservation Regeneration Riparian Okavango and wetlands

Role of the intestinal barrier in inflammatory bowel disease

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World Journal of Gastroenterology 2008年第3期14卷 401-407页

作者： mike G Laukoetter Porfirio Nava Asma Nusrat Epithelial Pathobiology Research Unit Department of Pathology and Laboratory Medicine Emory University Atlanta GA 30322 United States Department of General Surgery University of Muenster Muenster 48149 Germany Epithelial Pathobiology Research Unit Department of Pathology and Laboratory Medicine Emory University Atlanta GA 30322 United States

A critical function of the intestinal mucosa is to form a barrier that separates luminal contents from the interstitium. The single layer of intestinal epithelial cells (IECs) serves as a dynamic interface between the host and its environment. Cell polarity and structural properties of the epithelium is complex and is important in the development of epithelial barrier function. Epithelial cells associate with each other via a series of intercellular junctions. The apical most intercellular junctional complex referred to as the Apical Junction Complex (AJC) is important in not only cell-cell recognition, but also in the regulation of paracellular movement of fluid and solutes. Defects in the intestinal epithelial barrier function have been observed in a number of intestinal disorders such as inflammatory bowel disease (IBD). It is now becoming evident that an aberrant epithelial barrier function plays a central role in the pathophysiology of IBD. Thus, a better understanding of the intestinal epithelial barrier structure and function in healthy and disease states such as IBD will foster new ideas for the development of therapies for such chronic disorders.

关键词： Intestine Barrier function Tight Junction InflammatorY bowel disease Crohn's disease Ulcerativecolitis

Effects of High Salt Concentration and Residue on Copper and Aluminum Corrosion

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Chemical Research in Chinese Universities 2013年第3期29卷 538-544页

作者： HUO Ying TAN mike Yongjun SHU Li Faculty of Science and Technology School of Engineering Deakin University Victoria 3216 Australia

Traditional researches on metal corrosion under salt solutions deposit conditions are usually carried out by visual, electron microscopic observations and simple electrochemical measurement via a traditional one-piece electrode. These techniques have difficulties in measuring localized corrosion that frequently occur in inhomogeneous media. This paper reports the results from the experiments using specially shaped coupons and a relatively new method of measuring heterogeneous electrochemical processes, namely, the wire beam electrode（WBE）. Preliminary results from copper and aluminum corrosion in highly concentrated sodium chloride solutions with and without solid deposits show that the method is useful in simulating and studying corrosion especially localized corrosion in pipelines.

关键词： Copper Aluminum Mass loss Deposit corrosion General and pitting corrosion attack

The International Commission on the History of Geological Sciences （INHIGEO） Symposium on History of Geophysics

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Episodes 2006年第1期29卷 56-58页

作者： mike Johnston, Nelson NEW ZEALAND

The 30th INHIGEO Symposium, with its theme the ＇History of Geophysics＇, was held in the Czech Republic from 2-12 July 2005 and attracted 42 participants from 18 countries. It was hosted by the Geophysical Institute of the Czech Academy of Sciences （GFU） in Prague and was ably organised by Dr Jan Kozak of the Institute. The symposium commenced with a two-day field trip to West Bohemia led by Jiri Babdrek and Ondrej Jaiger of the Czech Geological Survey and PLA Czech Karst respectively. On leaving Prague and its well-bedded Paleozoic sedimentary rocks, the route taken ran northwest across gently rolling Bohemian landscape to the city of Most. On the outskirts of the city a change from Cretaceous sedimentary rocks to ones of Tertiary age was heraided by the appearance of numerous volcanic cones that mark the northeastern end of the Ohre River Rift Zone or Eger Graben.

关键词：地质科学捷克古生代地质工作第三纪

Difficulty of falling asleep and non-high-density lipoprotein cholesterol level among Canadian older adults:a cross-sectional analysis of the Canadian Longitudinal Study for Aging baseline data

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Journal of Geriatric Cardiology 2021年第8期18卷 597-608页

作者： Jian LIU Surim Son mike Giancaterino Miya Narushima Department of Health Sciences Brock UniversitySt.CatharinesOntarioCanada

OBJECTIVE To examine whether difficulty of falling asleep(DoFA)is associated with non-high-density lipoprotein cholesterol(non-HDL-C)level among Canadian older *** 26,954 individuals aged 45-85 years from the baseline data of the Canadian Longitudinal Study for Aging were in-cluded in this *** was categorized into five groups by answer to the question“Over the last month,how often did it take you more than 30 min to fall asleep?”Response options are“Never,<1 time/week,1−2 times/week,3−5 times/week,or 6−7 times/week”.Non-HDL-C,the difference of total cholesterol and HDL-C,were categorized into five categories based on these cut-offs(<2.6 mmol/L,2.6−3.7 mmol/L,3.7−4.8 mmol/L,4.8−5.7 mmol/L,and≥5.7 mmol/L).Ordinal logistic regression(logit link)continuation ratio models were used to estimate the odds of higher non-HDL-C levels for DoFA *** means of non-HDL-C by DoFA status were estimated by general linear *** analyses were sex separately using analytic weights to en-sure *** The proportions of DoFA in five categories were 41.6%,25.7%,13.6%,9.4%,9.7%for females and 52.9%,24.9%,10.5%,6.1%,5.6%for males,*** adjustment of demographical and other covariates(such as depression,comorbidity,sleeping hour,etc.)compared to those who reported never having DoFA,the ORs(95%CIs)of higher levels of non-HDL-C for those whose DoFA status in<1 time/week,1−2 times/week,3−5 times/week,and 6−7 times/week were 1.12(1.05−1.21),1.09(0.99−1.18),1.20(1.09−1.33),1.29(1.17−1.43)in females and 1.05(0.98−1.13),0.95(0.87−1.05),1.21(1.08−1.37),0.97(0.85−1.09)in males,*** adjusted means of non-HDL-C among the five DoFA status were 3.68 mmol/L,3.73 mmol/L,3.74 mmol/L,3.82 mmol/L,3.84 mmol/L for females and 3.54 mmol/L,3.58 mmol/L,3.51 mmol/L,3.69 mmol/L,3.54 mmol/L for males,*** The results of this study have identified a risk association pattern between DoFA status and non-HDL-C levels in females

关键词： cholesterol sectional Canadian

A New Solution Architecture for Online Power System Analysis

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CSEE Journal of Power and Energy Systems 2018年第2期4卷 250-256页

作者： mike Zhou Jianfeng Yan State Grid Electric Power Research Institute Beijing 100192China China Electric Power Research Institute Beijing 100192China

The current DSA system used in the dispatching control centers in China is a near real-time analysis system with response speed in the order of *** on a review of the state-of-the-art in online analysis and discussion of distributed data processing and computation architecture patterns,a new online analysis architecture is *** primary goal of the new architecture is to increase the online analysis response speed to the order of seconds.A reference implementation of the proposed online analysis architecture to validate the feasibility of implementing the architecture and some performance testing results are presented.

关键词： CEP complex event processing DSA EMS in-memory computing power grid modeling power system online analysis

An Automatic Method to Identify Citations to Journals in News Stories: A Case Study of UK Newspapers Citing Web of Science Journals

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Journal of Data and Information Science 2019年第3期4卷 73-95页

作者： Kayvan Kousha mike Thelwall Statistical Cybermetrics Research Group School of Mathematics and Computer ScienceUniversity of Wolverhampton

Purpose: Communicating scientific results to the public is essential to inspire future researchers and ensure that discoveries are exploited. News stories about research are a key communication pathway for this and have been manually monitored to assess the extent of press coverage of ***/methodology/Approach: To make larger scale studies practical, this paper introduces an automatic method to extract citations from newspaper stories to large sets of academic journals. Curated ProQuest queries were used to search for citations to 9,639 Science and3,412 Social Science Web of Science(WoS) journals from eight UK daily newspapers during2006–2015. False matches were automatically filtered out by a new program, with 94% of the remaining stories meaningfully citing ***: Most Science(95%) and Social Science(94%) journals were never cited by these newspapers. Half of the cited Science journals covered medical or health-related topics,whereas 43% of the Social Sciences journals were related to psychiatry or psychology. From the citing news stories, 60% described research extensively and 53% used multiple sources,but few commented on research *** Limitations: The method has only been tested in English and from the ProQuest Newspapers *** implications: Others can use the new method to systematically harvest press coverage of ***/value: An automatic method was introduced and tested to extract citations from newspaper stories to large sets of academic journals.

关键词： Citation analysis News stories Public engagement Public impact UK newspapers Web of Science journals

How Has Covid-19 Affected Published Academic Research?A Content Analysis of Journal Articles Mentioning the Virus

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Journal of Data and Information Science 2021年第4期6卷 1-12页

作者： mike Thelwall Saheeda Thelwall Statistical Cybermetrics Research Group University of WolverhamptonUK Institute of Health University of WolverhamptonUK

Purpose:Methods to tackle Covid-19 have been developed by a wave of biomedical research but the pandemic has also influenced many aspects of society,generating a need for research into its consequences,and potentially changing the way existing topics are *** article investigates the nature of this influence on the wider academic research ***/methodology/approach:This article reports an inductive content analysis of 500 randomly selected journal articles mentioning Covid-19,as recorded by the Dimensions scholarly database on 19 March ***-19 mentions were coded for the influence of the disease on the ***:Whilst two thirds of these articles were about biomedicine(***,vaccines,virology),or health services in response to Covid-19,others covered the pandemic economy,society,safety,or *** addition,some articles were not about the pandemic but stated that Covid-19 had increased or decreased the value of the reported research or changed the context in which it was *** limitations:The findings relate only to Covid-19 influences declared in published journal *** implications:Research managers and funders should consider whether their current procedures are effective in supporting researchers to address the evolving demands of pandemic societies,particularly in terms of ***/value:The results show that although health research dominates the academic response to Covid-19,it is more widely disrupting academic research with new demands and challenges.

关键词： Covid-19 Pandemic Bibliometrics Scientometrics Publication analysis Research management

Data Center Power System Stability-Part II: System Modeling and Analysis

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CSEE Journal of Power and Energy Systems 2022年第2期8卷 420-438页

作者： Jian Sun Melaku Mihret Mauricio Cespedes David Wong mike Kauffman Rensselaer Polytechnic Institute-ECSE 1108th Street Room CII 8015Troy 12180United States Meta Platforms Inc. 1601 Willow RdMenlo ParkCalifornia 94025-1452United States

This is the second part of a two-part paper on stability study of data center power systems by impedance-based *** the basis for this application,Part I[1]developed new impedance models for power supplies that are the most dominant loads in data *** second part presents system modeling and analysis methods that can support practical data center power system design to ensure *** proposed methods comprise:1)building distribution network modeling by impedance scaling;2)system modeling and model reduction based on equivalent source impedance;3)system stability analysis in the sequence domain to include zero-sequence dynamics;and 4)expansion of system models and analyses to account for network asymmetry and uneven *** methods are used to characterize practical resonance problems observed in data centers,explain their root causes,and develop *** systems using Y-connected power supply units(PSUs),the zero sequence is identified as the weakest link and the first to become *** expanded system model and analysis reveal a new,differential-mode instability that is responsible for high frequency *** guarantee system stability,new impedance-based product and system design specifications are developed based on sufficient conditions derived from the Nyquist stability *** and field measurements are presented to substantiate the proposed methods and conclusions.

关键词： Data center power systems frequency-domain methods impedance modeling system stability system resonance