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今日科技 2002年第12期22卷 10-11页

作者： michael g.Zey 刘增义

Importance of overstorey attributes for understorey litter production and nutrient cycling in European forests

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Forest Ecosystems 2020年第4期7卷 591-601页

作者： Dries Landuyt Evy Ampoorter Cristina CBastias Raquel Benavides Sandra Müller michael Scherer-Lorenzen Fernando Valladares Safaa Wasof Kris Verheyen Forest&Nature Lab Department of EnvironmentGhent UniversityGhentBelgium LINCglobal Department of Biogeography and Global ChangeNational Museum of Natural Science-CSICMadridSpain Faculty of Biology GeobotanyUniversity of FreiburgFreiburg im BreisgauGermany.

Background:In contrast with the negligible contribution of the forest understorey to the total aboveground phytobiomass of a forest,its share in annual litter production and nutrient cycling may be more *** and how this functional role of the understorey differs across forest types and depends upon overstorey characteristics remains to be ***:We sampled 209 plots of the FunDivEUROPE Exploratory Platform,a network of study plots covering local gradients of tree diversity spread over six contrasting forest types in *** estimate the relative contribution of the understorey to carbon and nutrient cycling,we sampled non-lignified aboveground understorey biomass and overstorey leaf litterfall in all *** samples were analysed for C,N and P concentrations,overstorey leaf litterfall for C and N *** additionally quantified a set of overstorey attributes,including species richness,proportion of evergreen species,light availability(representing crown density)and litter quality,and investigated whether they drive the understorey’s contribution to carbon and nutrient *** and conclusions:Overstorey litter production and nutrient stocks in litterfall clearly exceeded the contribution of the understorey for all forest types,and the share of the understorey was higher in forests at the extremes of the climatic *** most of the investigated forest types,it was mainly light availability that determined the contribution of the understorey to yearly carbon and nutrient *** species richness did not affect the contribution of the understorey to carbon and nutrient cycling in any of the investigated forest types.

关键词： FunDivEUROPE Nutrient cycling Litter production Understorey Overstorey Tree species richness Light availability Litter quality Proportion evergreen tree species

Relevance of MUC1 mucin variable number of tandem repeats polymorphism in H pylori adhesion to gastric epithelial cells

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World Journal of gastroenterology 2008年第9期14卷 1411-1414页

作者： Natália R Costa Nuno Mendes Nuno T Marcos Celso A Reis Thomas Caffrey michael A Hollingsworth Filipe Santos-Silva Institute of Molecular Pathology and Immunology University of PortoPorto 4200-465Portugal Institute of Molecular Pathology and Immunology University of Porto Porto 4200-465Portugal Medical Faculty University of Porto Porto 4200-465Portugal Eppley Institute for Research in Cancer and Allied Diseases University of Nebraska Medical CenterOmaha 68198-6805United States Institute of Molecular Pathology and Immunology University of PortoPorto 4200-465Portugal

AIM:To evaluate the influence of MUC1 mucin variable number of tandem repeats (VNTR) variability on H pylori adhesion to gastric cells. METHODS: Enzyme linked immunosorbent assay (ELISA)-based adhesion assays were performed to measure the adhesion of different H pylori strains (HP26695 and HPTx30a) to gastric carcinoma cell lines (gP202 and MKN45) and gP202 clones expressing recombinant MUC1 with different VNTR lengths. RESULTS: Evaluation of adhesion results shows that H pylori pathogenic strain HP26695 has a significantly higher (P genic strain HPTx30a. Bacteria showed a significantly higher (P gP202 cell line, when compared to the MKN45 cell line. Furthermore, both strains showed a significantly higher (P gP202 clones with larger MUC1 VNTR domains. CONCLUSION: This work shows that MUC1 mucin variability conditions H pylori binding to gastric cells. The extent of bacterial adhesion depends on the size of theMUC1 VNTR domain. The adhesion is further dependent on bacterial pathogenicity and the gastric cell line. MUC1 mucin variability may contribute to determine H pylori colonization of the gastric mucosa.

关键词： Hpylori MUC1 Variable number of tandem repeats Polymorphism Adhesion Mucin gastric Infection

Significant association between ABO blood group and pancreatic cancer

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World Journal of gastroenterology 2010年第44期16卷 5588-5591页

作者： Julia B greer Mark H Yazer Jay S Raval M michael Barmada Randall E Brand David C Whitcomb Department of Medicine Division of GastroenterologyHepatology and NutritionUniversity of Pittsburgh School of Medicine Department of Pathology University of Pittsburgh School of Medicine The Institute for Transfusion Medicine Department of Human genetics Graduate School of Public HealthUniversity of Pittsburgh University of Pittsburgh Cancer Institute

AIM:To evaluate whether the ABO blood group is related to pancreatic cancer risk in the general population of the United ***:Using the University of Pittsburgh's clinicalpancreatic cancer registry,the blood donor database from our local blood bank (Central Blood Bank),and the blood product recipient database from the regional transfusion service (Centralized Transfusion Service) in Pittsburgh,Pennsylvania,we identified 274 pancreatic cancer patients with previously determined serological ABO blood group *** ABO blood group frequency was compared between these patients and 708842 individual,community-based blood donors who had made donations to Pittsburgh's Central Blood Bank between 1979 and ***:The frequency of blood group A was statistically significantly higher amongst pancreatic cancer patients compared to its frequency amongst the regional blood donors [47.63% vs 39.10%,odds ratio (OR)=1.43,P=0.004].Conversely,the frequency of blood group O was significantly lower amongst pancreatic cancer patients relative to the community blood donors (32.12% vs 43.99%,OR=0.60,P=0.00007).There were limited blood group B (n=38) and AB (n=17) pancreatic cancer patients;the overall P trend value comparing patient to donor blood groups was ***:The ABO blood group is associated with pancreatic cancer *** studies should examine the mechanism linking pancreatic cancer risk to ABO blood group.

关键词： ABO blood group Pancreatic adenocarcinoma Surveillance Risk reduction Epidemiology

Bone targeted nano-drug and nano-delivery

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Bone Research 2024年第3期12卷 517-538页

作者： Yilun Wu Bing Sun Ying Tang Aining Shen Yanlin Lin Xiaohui Zhao Jingui Li michael J.Monteiro Wenyi gu College of Biotechnology and Pharmaceutical Engineering Nanjing Tech UniversityNanjingChina Australian Institute for Bioengineering and Nanotechnology The University of QueenslandSt.LuciaQLDAustralia Science and Technology Innovation Centre Guangzhou University of Chinese MedicineGuangzhouChina Shenzhen Bay Laboratory ShenzhenGuangdongChina gMU-gIBH Joint School of Life Sciences Guangzhou Medical UniversityGuangzhouChina School of Veterinary Medicine Jiangsu Coinnovation Centre for Prevention and Control of Important Animal Infectious Diseases and ZoonosesYangzhou UniversityYangzhouChina

There are currently no targeted delivery systems to satisfactorily treat bone-related *** clinical drugs consisting of small organic molecules have a short circulation half-life and do not effectively reach the diseas... 详细信息

关键词： repeatedly satis targeted

Statistical landslide susceptibility assessment in a dynamic environment:A case study for Lanzhou City,gansu Province,NW China

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Journal of Mountain Science 2018年第6期15卷 1299-1318页

作者： TORIZIN Jewgenij WANg Li-chao FUCHS michael TONg Bin BALZER Dirk WAN Li-qin KUHN Dirk LI Ang CHEN Liang Federal Institute for geosciences and Natural Resources （BgR） Hannover 30655 Germany China Institute of geo-environment Monitoring （CIgEM） Beijing 100081 China

This study presents a statistical landslide susceptibility assessment(LSA) in a dynamic environment. The study area is located in the eastern part of Lanzhou, NW China. The Lanzhou area has exhibited rapid urbanization rates over the past decade associated with greening, continuous land use change, and geomorphic reshaping activities. To consider the dynamics of the environment in the LSA, multitemporal data for landslide inventories and the corresponding causal factors were collected. The weights of evidence(Wof E) method was used to perform the LSA. Three time stamps, i.e., 2000, 2012, and 2016, were selected to assess the state of landslide susceptibility over time. The results show a clear evolution of the landslide susceptibility patterns that was mainly governed by anthropogenic activities directed toward generating safer building grounds for civil infrastructure. The low and very low susceptibility areas increased by approximately 10% between 2000 and 2016. At the same time, areas of medium, high and very high susceptibility zones decreased proportionally. Based on the results, an approach to design the statistical LSA under dynamic conditions is proposed, the issues and limitations of this approach are also discussed. The study shows that under dynamic conditions, the requirements for data quantity and quality increase significantly. A dynamic environment requires greater effort to estimate the causal relations between the landslides and controlling factors as well as for model validation.

关键词： Landslide susceptibility assessment Dynamic environment Weights of evidence method Validation Urbanization Lanzhou City

Chronic training status affects muscle excitation of the vastus lateralis during repeated contractions

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Sports Medicine and Health Science 2023年第1期5卷 42-49页

作者： Sunggun Jeon Stephanie A.Sontag Trent J.Herda michael A.Trevino Applied Neuromuscular Physiology Laboratory Department of KinesiologyApplied Healthand RecreationOklahoma State UniversityStillwaterOKUSA Neuromechanics Laboratory Department of HealthSportand Exercise SciencesThe University of KansasLawrenceKSUSA

This study examined electromyographic amplitude(EMgRMS)-force relationships during repeated submaximal knee extensor muscle actions among chronic aerobically-(AT),resistance-trained(RT),and sedentary(SED)*** adults(5/group)attempted 20 isometric trapezoidal muscle actions at 50%of maximal *** electromyography(EMg)was recorded from vastus lateralis(VL)during the muscle *** the first and last successfully completed contractions,linear regression models were fit to the log-transformed EMgRMS-force relationships during the linearly increasing and decreasing segments,and the b terms(slope)and a terms(antilog of y-intercept)were *** was averaged during steady *** the AT completed all 20 muscle *** the first contraction,the b terms for RT(1.3010.197)were greater than AT(0.9100.123;p?0.008)and SED(0.9120.162;p?0.008)during the linearly increasing segment,and in comparison to the linearly decreasing segment(1.0180.139;p?0.014),*** the last contraction,the b terms for RT were greater than AT during the linearly increasing(RT?1.3730.353;AT?0.8830.129;p?0.018)and decreasing(RT?1.5260.328;AT?0.9700.223;p?0.010)*** addition,the b terms for SED increased from the linearly increasing(0.9680.144)to decreasing segment(1.2680.126;p?0.015).There were no training,segment,or contraction differences for the a *** during steady force increased from the first-([64.0851.68]μV)to last-contraction([86.7349.55]μV;p?0.001)collapsed across training *** b terms differentiated the rate of change for EMgRMS with increments in force among training groups,indicating greater muscle excitation to the motoneuron pool was necessary for the RT than AT during the linearly increasing and decreasing segments of a repetitive task.

关键词： Electromyography Fatigue Isometric trapezoidal muscle action Motor unit control properties Natural log-transformed model Vastus lateralis

Sampling-Based Approaches to Estimating Two-Dimensional Large Wood Area from UAS Imagery

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Journal of geographic Information System 2022年第6期14卷 571-588页

作者： Matthew I. Barker Jonathan D. Burnett Francisco Mauro gutiérrez Steven M. Wondzell michael g. Wing Forest Engineering Resources and Management Department College of Forestry Oregon State University Corvallis OR USA USDA Forest Service Pacific Northwest Research Station Corvallis OR USA EiFAB—iuFOR Campus Duques de Soria s/n Universidad de Valladolid Soria Spain

Large in-stream wood (LW) is a critical component of riparian systems that increases heterogeneity of flow regimes and provides high quality habitat for salmonids and other fishes. We present four sampling-based methods to estimate two-dimensional LW for a 61-hectare river restoration project on the South Fork McKenzie River near Rainbow, OR (USA). We manually delineated LW area, from unoccupied aircraft systems (UAS) multispectral imagery for 40 randomly selected 51.46 m2 hexagonal plots. Seven auxiliary variables were extracted from the imagery and imagery derivatives to be incorporated in four estimators by summarizing spectral statistics for each plot including Random forest (RF) classification of segmented imagery (Cohen’s kappa = 0.75, balanced accuracy = 0.86). The four estimators were: difference estimator, simple linear regression estimator with one auxiliary variable, general regression estimator with seven auxiliary variables, and simple random sample without replacement. We assessed variance of the estimators and found that the simple random sample without replacement produced the largest estimate for LW area and widest confidence interval (17,283 m2, 95% CI 10,613 - 23,952 m2) while the generalized regression approach resulted in the smallest estimate and narrowest confidence interval (16,593 m2, 95% CI 13,054 - 20,133 m2). These methods facilitate efficient estimates of critical habitat components, that are especially suited to efforts that seek to quantify large amounts of these components through time. When combined with traditional sampling methods, classified imagery acquired via UAS promises to enhance the temporal resolution of the data products associated with restoration efforts while minimizing the necessity for potentially hazardous field work.

关键词： UAS Large in-Stream Wood Sampling Image Classification River Restoration

Reduce Plasticizer Migration by Modification of PVC during Reactive Processing

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中山大学学报（自然科学版） 2003年第A19期42卷 84-87页

作者： XINg X S SCOTT g Department of Physics and Materials Science City University of Hong Kong Kowloon Hong Kong ChinaDepartment of Chemistry and Chemical Engineering University of Aston in Birmingham B4 7 ET UK

Plasticizers in plasticized polyvinyl chloride (PVC) are generally physically added into PVC by compounding so that they can be rapidly leached from PVC articles during service. This results in their migration into the human environment with potentially serious consequences and lower effectiveness of the additives in PVC. Potentially the chemical modification of PVC during processing via reactive processing procedure is one of the most attractive solutions to these problems. In this paper, we will report our work in exploring an environmentally friendly and cost-effective reactive processing approach for chemically binding plasticizer into PVC chains. Our research results indicate that it is possible to reduce the plasticizer migration from a plasticized PVC by chemically binding of a certain plasticizer into PVC chains via reactive processing. Thus, high levels of binding of DBM,a maleate plasticizer, to PVC may be reached in less than 10 min under prevailing reactive processing conditions. The extent of binding of DBM as a function of the loading shows two peaks: one at a relatively low loading (less than 0.12 mol·kg^-1 PVC) tends to 100%, the other in the high loading region (more than 1.5 mol·kg^-1 PVC) approaches around 50%. The DBM modified PVC polymer exhibits behaviours as a plasticized PVC but its bound plasticising groups would not be leached by solvent extraction.

关键词：聚氯乙烯增塑剂损耗电抗性处理化学修饰

Semen microbiota and cytokines of healthy and infertile men

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Asian Journal of Andrology 2022年第4期24卷 353-358页

作者： Oleg V Bukharin Natalya B Perunova Elena V Ivanova Irina N Chaynikova Anastasia V Bekpergenova Taisiya A Bondarenko michael D Kuzmin Institute of Cellular and Intracellular Symbiosis Ural Department of the Russian Academy of SciencesOrenburg Federal Research Center UD of RASOrenburg 460014Russia

In this study,we determined the levels of cytokine secretory inhibitors and the microbiota biofilms of semen from healthy and infertile subjects.A total of 118 clinical bacterial isolates were isolated and *** secretory inhibitors were determined based on the difference in cytokine content between the control and experimental samples of cell-free supernatants of isolated *** formation was studied by determining the adhesion of microorganisms to the surface of a 96-well sterile plate and expressed as the optical density at 630 nm(OD_(630)).Cell-free supernatants of Staphylococcus contained higher levels of secretory inhibitor of cytokines in conditionally healthy than in infertile *** contrast,in infertile men,the ability to reduce cytokine levels was more characteristic of Enterococcus and *** Staphylococcus,Corynebacterium,and Enterococcus isolated from infertile subjects showed a greater ability to form biofilms than the same bacteria isolated from healthy *** research is needed on this topic,since it is necessary to determine the relationships between decreased secretory inhibitors of cytokines,production of biofilms by bacteria in semen,and *** is likely that the ability of microorganisms to change the concentration of cytokines and increase the level of biofilm formation in semen may be associated with minimal impairments of fertilizing ability,which are not detected using other methods.

关键词： biofilms infertility microbiota secretory inhibitor of cytokines semen