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Community phylogenetic diversity and abiotic site characteristics influence abundance of the invasive plant Rhamnus cathartica L.

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Journal of Plant Ecology 2014年第2期7卷 202-209页

作者： Timothy J.S.Whitfeld Alexandra G.Lodge Alexander M.Roth Peter b.Reich Department of Forest Resources University of Minnesota1530 Cleveland Avenue NorthSt PaulMN 55108-6112USA Hawkesbury Institute for the Environment University of Western SydneyPenrithNSW 2751Australia

Aims Theory predicts that the success of introduced species is related to the diversity of native species through trait-based *** site characteristics may also affect a site’s susceptibility to *** quantified resident plant species richness,phylogenetic diversity and several abiotic site characteristics for 24 oak forests in Minnesota,USA,to assess their impact on the abundance of a widespread,introduced terrestrial plant species,common buckthorn(Rhamnus cathartica L.).Specifically,we asked(1)whether resident species richness and phylogenetic diversity affected the abundance of *** and(2)what site characteristics explained the overall abundance of *** Our survey included 24 oak-dominated stands in Minnesota’s deciduous *** each stand,we identified all species in 16 *** also measured a series of environmental site characteristics,including canopy openness(a proxy for light availability),percent bare soil,soil pH,percent sand,an index of propagule availability,duff layer thickness(a proxy for earthworm activity),an index of insolation and *** all species present in at least one site,we estimated a community *** combined all sitelevel characteristics,including phylogenetic diversity of the resident plant species,in a multiple regression model to examine site-level drivers of community *** Findings Results indicate that sites with higher overall plant phylogenetic diversity harbor less ***,even though native species richness was not significantly related to *** *** analyses indicated that,in addition to resident species phylogenetic diversity,the most important predictors of *** abundance were canopy openness and the amount of bare soil,both positively related to the abundance of the *** combining the effects of abiotic site characteristics and resident species phylogenetic diversity in a model that predicted the abundance of R

关键词： invasibility R.cathartica L. phylogenetic diversity site characteristics

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Longitudinal assessment of liver stiffness by transient elastography for chronic hepatitis C patients

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World Journal of Clinical Cases 2022年第17期10卷 5566-5576页

作者： Anya Mezina Arunkumar Krishnan Tinsay A Woreta Kevin b Rubenstein Eric Watson Po-Hung Chen Carla Rodriguez-Watson Department of Medicine Johns Hopkins School of MedicineBaltimoreMD 21287United States Division of Gastroenterology and Hepatology Johns Hopkins School of MedicineBaltimoreMD 21231United States Mid-Atlantic Permanente Research Institute Kaiser Permanente Mid-Atlantic StatesRockville 20852United States Department of Health Policy and Management Bloomberg School of Public HealthJohns Hopkins UniversityBaltimoreMD 21287United States Innovation in Medical Evidence Development and Surveillance(IMEDS)Program Reagan-Udall Foundation for the FDAWashington20036United States

bACKGROUND Liver fibrosis is a common pathway of liver injury and is a feature of most chronic liver *** progression varies markedly in patients with hepatitis C virus(HCV).Liver stiffness has been recommended as a parameter of fibrosis progression/regression in patients with *** To investigate changes in liver stiffness measured by transient elastography(TE)in a large,racially diverse cohort of United States patients with chronic hepatitis C(CHC).METHODS We evaluated the differences in liver stiffness between patients treated with direct-acting antiviral(DAA)therapy and untreated *** had≥2 TE measurements and no prior DAA *** used linear regression to measure the change in liver stiffness between first and last TE in response to treatment,controlling for age,sex,race,diabetes,smoking status,human immunodeficiency virus status,baseline alanine aminotransferase,and baseline liver *** regression models analyzed the change in liver stiffness as measured by kPa,stratified by cirrhosis *** Of 813 patients,419(52%)initiated DAA *** liver stiffness was 12 kPa in 127(16%).Median time between first and last TE was 11.7 and 12.7 mo among treated and untreated patients,*** was no significant change in liver stiffness observed over time in either the group initiating DAA treatment(0.016 kPa/month;CI:-0.051,0.084)or in the untreated group(0.001 kPa/mo;CI:-0.090,0.092),controlling for covariates.A higher baseline kPa score was independently associated with decreased liver *** DAA treatment was not associated with a differential change in liver stiffness over time in patients with CHC compared to untreated patients.

关键词： Chronic hepatitis C Liver stiffness Cirrhosis Transient elastography Direct-acting antiviral therapy

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W-CDMA/UMTS下一种解决TCP有效性和公平性的跨层方案

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电子与信息学报 2006年第11期28卷 2081-2085页

作者：王晓利 G.b 纪红乐光新北京邮电大学电信工程学院北京100876

在UMTS系统中,由于MAC层的包调度引入了用户间的竞争,带来了传输层TCP有效性和公平性问题,为了解决这个问题,该文提出了一种主动ACK包转发控制策略(AAFC),它的基本思想是在基站处嵌入AAFC模块,通过MAC层和传输层之间的消息传递来控制基... 详细信息

在UMTS系统中,由于MAC层的包调度引入了用户间的竞争,带来了传输层TCP有效性和公平性问题,为了解决这个问题,该文提出了一种主动ACK包转发控制策略(AAFC),它的基本思想是在基站处嵌入AAFC模块,通过MAC层和传输层之间的消息传递来控制基站处ACK包的转发,以此来保证用户间TCP流的公平性以及链路层无线资源的最充分利用。仿真结果证明了AAFC方案的有效性。

关键词： TCP UMTS 包调度公平性有效性

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Functionalization of micropipette tips with hydrophobin-laccase chimera and application to the electrochemical determination of caffeic acid in tea samples

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Food bioscience 2023年第2期52卷 1362-1368页

作者： Ilaria Stanzione Anna Pennacchio Alessandra Piscitelli Paola Giardina b Estefania Costa-Rama M.Teresa Fernandez-Abedul Department of Physical and Analytical Chemistry University of OviedoSpain Department of Chemical Sciences University of Naples“Federico II”Italy

Performing on-site measurements is one of the main challenges of current(bio)chemical *** tips,which are among the most common utilities in laboratories,can be useful and cheap elements for designing out-of-the-box innovative analytical ***,most of the analytical properties of these bioplatforms depend on the immobilization of the recognition element(e.g.,enzymes).In this context,we have recently designed a chimeric protein in which laccase PoxA1b from the fungus Pleurotus ostreatus has been genetically fused to the class I hydrophobin *** ability to self-assemble at hydrophobic-hydrophilic interfaces of hydrophobin,allows an easy laccase *** this work,the Vmh2-PoxA1b fusion protein was immobilized into common polypropylene micropipette tips to develop an innovative enzymatic bioplatform that can produce fast results in a simple *** proof of applicability,the platform was applied to the determination of caffeic acid by enzymatic oxidation and further electrochemical reduction of the product on a screen-printed electrode,achieving a limit of detection of 1.4-10^(-6) *** was then used for determining caffeic acid in tea samples.

关键词： Fusion protein Laccase Micropipette tips Electrochemical detection Caffeic acid

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bIG-bANG NUCLEOSYNTHESIS

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Chinese Physics C 2016年第10期40卷 380-385页

作者： b.D. Fields P. Molaro S. Savkar Univ. of Illinois Trieste Observatory Univ. of Oxford & Niels bohr Institute Copenhagen

big-bang nucleosynthesis （bbN） offers the deepest reliable probe of the early Universe, being based on well-understood Standard Model physics [1]. Predictions of the abundances of the light elements, D, 3He, 4He, and 7Li, synthesized at the end of the ＇first three minutes＇, are in good overall agreement with the primordial abundances inferred from observational data, thus validating the standard hot big-bang cosmology （see [2-5] for reviews）.

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A modeling study of relation between cloud amount and SST over Western Tropical Pacific cloudy regions during TOGA COARE

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Progress in Natural Science:Materials International 2009年第2期19卷 187-193页

作者： Shouting Gaoa,Xiaopeng Cui a,Xiaofan Li b a Laboratory of Cloud-Precipitation Physics and Severe Storms (LACS),Institute of Atmospheric Physics,Chinese Academy of Sciences,beijing 100029,China b Joint Center for Satellite Data Assimilation and NOAA/NESDIS/Center for Satellite Applications and Research,Camp Springs,MD,USA Laboratory of Cloud-Precipitation Physics and Severe Storms (LACS) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Joint Center for Satellite Data Assimilation and NOAA/NESDIS/Center for Satellite Applications and Research Camp Springs MD USA

The relationship between cloud amount and sea surface temperature (SST) over Western Tropical Pacific cloudy regions during TOGA COARE is investigated based on hourly grid simulation data from a two-dimensional coupled ocean-cloud resolving atmosphere model. The model is forced by the large-scale vertical velocity and zonal wind observed and derived from TOGA COARE for a 50-day period. The cloud amount becomes smaller when the ocean surface gets warmer,which is similar to previous relations obtained from observational analyses. As SST increases,the atmospheric temperature increases whereas the surface sensible heat flux decreases. The atmospheric water vapor is not sensitive to SST whereas the surface evaporation flux decreases as SST increases. These indicate that the oceanic effects do not play an important role in determining atmospheric heat and water vapor budgets. The cold atmosphere pro-duces a larger amount of ice clouds that cover a larger area than the warm atmosphere does. The large amounts of ice clouds lead to cooling of the ocean surface through reflecting large amount of solar radiation back to the space. Thus,the negative correlation between the cloud amount and SST only accounts for the important atmospheric effects on the ocean.

关键词： Cloud amount Sea surface temperature Coupled ocean-cloud resolving atmosphere model TOGA COARE

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Improvement in the corrosion protection and bactericidal properties of AZ91D magnesium alloy coated with a microstructured polypyrrole film

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Journal of Magnesium and Alloys 2018年第1期6卷 15-22页

作者： A.D.Forero López I.L.Lehr L.I.brugnoni S.b.Saidman Instituto de Ingeniería Electroquímica y Corrosión(INIEC) Departamento de Ingeniería QuímicaUniversidad Nacional del SurAv.Alem 12538000 Bahía BlancaArgentina Instituto de Investigaciones biológicas y biomédicas del Sur(INbIOSUR) Departamento de BiologíaBioquímica y FarmaciaUniversidad Nacional del SurSan Juan 6708000 Bahía BlancaArgentina

In this work hollow rectangular microtubes of polypyrrole(PPy)films were potentiostatically electrodeposited on magnesium alloy AZ91D in salicylate *** substrate was previously anodized under potentiostatic conditions in a molybdate solution in order to improve the adherence of *** the duplex film was modified by the incorporation of silver *** obtained coatings were characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD)and X-ray photoelectron spectroscopies(XPS)and the antimicrobial activity against the bacteria Escherichia coli was *** corrosion protection properties of the coatings were examined in Ringer solution by monitoring the open circuit potential,polarization techniques and electrochemical spectroscopy(EIS).The duplex coating presents an improved anticorrosive performance with respect to the PPy *** best results concerning corrosion protection and antibacterial activity were obtained for the silver-modified composite coating.

关键词： Polypyrrole Duplex coating AZ91D alloy Corrosion resistance Antibacterial properties

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DISCRETE PARTICLE SIMULATION OF SIZE SEGREGATION OF PARTICLE MIXTURES IN A GAS FLUIDIZED bED

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China Particuology 2006年第3期4卷 122-126页

作者： Y. Q. Feng A. b. Yu Center for Simulation and Modelling of Particulate Systems School of Materials Science and Engineering The University of New South Wales Sydney NSW 2052 Australia Divisions of Minerals Commonwealth Scientific and Industrial Research Organization Box 312 Clayton South Victoria 3169 Australia

This paper presents a study of the mixing/segregation behaviour of particle mixtures in a gas fluidized bed by use of the discrete particle simulation. Spherical particles with diameters 2 mm （jetsam） and 1 mm （flotsam） and density 2 500 kg.m^-3 are used as solid mixtures with different volume fractions. The particles are initially packed uniformly in a rectangular bed and then fluidized by gas uniformly injected at the bottom of the bed. The gas injection velocities vary to cover fixed, partially and fully fluidized bed conditions. Segregation/mixing behaviour is discussed in terms of flow patterns, solid concentration profile and mixing kinetics. The results show that segregation, as a transient fluidization process, is strongly affected by gas injection velocities for a given particle mixture. With the increase of the volume fraction of flotsam, size segregation appears at lower velocities.

关键词： gas fluidization segregation discrete particle simulation

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In vivo printing of growth factor-eluting adhesive scaffolds improves wound healing

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bioactive Materials 2022年第2期7卷 296-308页

作者： Kristo Nuutila Mohamadmahdi Samandari Yori Endo Yuteng Zhang Jacob Quint Tannin ASchmidt b Ali Tamayol Indranil Sinha Division of Plastic Surgery Brigham and Women’s HospitalHarvard Medical SchoolBostonMA02115USA Department of biomedical Engineering University of ConnecticutFarmingtonCT06030USA Department of Mechanical and Materials Engineering University of Nebraska-LincolnLincolnNE68588USA

Acute and chronic wounds affect millions of people around the world,imposing a growing financial burden on patients and *** the application of current wound management strategies,the physiological healing process is disrupted in many cases,resulting in impaired wound ***,more efficient and easy-to-use treatment modalities are *** this study,we demonstrate the benefit of in vivo printed,growth factor-eluting adhesive scaffolds for the treatment of full-thickness wounds in a porcine model.A custom-made handheld printer is implemented to finely print gelatin-methacryloyl(GelMA)hydrogel containing vascular endothelial growth factor(VEGF)into the *** vitro and in vivo results show that the in situ GelMA crosslinking induces a strong scaffold adhesion and enables printing on curved surfaces of wet tissues,without the need for any *** scaffold is further shown to offer a sustained release of VEGF,enhancing the migration of endothelial cells in *** analyses demonstrate that the administration of the VEGF-eluting GelMA scaffolds that remain adherent to the wound bed significantly improves the quality of healing in porcine *** introduced in vivo printing strategy for wound healing applications is translational and convenient to use in any place,such as an operating room,and does not require expensive bioprinters or imaging modalities.

关键词： In vivo printing Handheld bioprinter Adhesive scaffolds GelMA VEGF Wound healing

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China: between Social Stability and Market Integration

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China & World Economy 2006年第3期14卷 95-108页

作者： Giovanni b. Andornino Russell G. Wilcox PhD Candidate Catholic University of Milan Italy. PhD Candidate School of Oriental and African Studies UK

China＇s gradual integration with the global market is responsible for exceptional rates of economic growth and for the substantial sociopolitical stability enjoyed by the country over the past decades. Nevertheless, the choice to increasingly adhere to the competitive dynamic of the market has thrown up a battery of problems for China＇s leadership, as increasing affluence has favored the pluralization and diversification of social interests. In a country where the existence of divergent and competing social claims has traditionally been regarded as a grave threat to stability, marketization, whereas on the one hand acting as a source of political legitimacy, has, on the other, paved the way for a potentially more strained relationship between relevant corporative interests and the central government. by studying China＇s recent development from the complementary perspectives of the ＂horizontal＂ and ＂vertical＂ forms of decentralization and devolution, this paper aims to highlight the tensions with which China has had to contend since its adoption of reform and opening-up policies in the late 1970s. It aims also to suggest how the Chinese leadership＇s instinct for continued social control has cut against market reform just enough to effect a process of controlled macroeconomic integration that has been more successful than wholesale resistance or immediate unquestioning acceptance would have been.

关键词： China decentralization globalization market integration

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