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Journal of Hydrodynamics 2013年第2期25卷 288-293页

作者： HORPPILA Jukka KAITARANTA Joni JOENSUU laura NURMINEN Leena Department of Environmental Sciences University of Helsinki

The effects of the emergent macrophyte Phragmites australis on water turbulence, bottom shear velocity and water turbidity were experimentally studied with the stem densities 0 stems/m2-100 stems/m2 and using organic-rich sediment. It is found that the maximum root-mean-square （rms） velocity and shear velocity decrease linearly with increasing stem density. By affecting the height of peak turbulence values, emergent plants can thus lower the frequency of sediment erosion events. Additionally, the slope of the rms turbulence increment decreases with increasing stem density. Thus, also the duration of strong turbulence is affected by the density of emergent macrophytes. The critical shear velocity for sediment resuspension is 0.0035 m/s-0.0055 rn/s and not affected by the stem density. In the absence of macrophytes, water flow causes a 6.3-fold increment in turbidity, but with macrophytes turbidity values remain lower. The experiments suggest that even relatively low densities of Phragmites can have substantial effects on water turbulence and consequently on water quality.

关键词： emergent macrophytes turbulence shear velocity resuspension turbidity

Distribution of action movements （DAM）： a descriptor for human action recognition

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Frontiers of Computer Science 2015年第6期9卷 956-965页

作者： Franco RONCHETTI Facundo QUIROGA laura LANZARINI Cesar ESTREBOU Instituto de Investigacion en Informatica III-LIDI Facultad de Informatica Universidad Nacional de La Plata La Plata B 1900AWX Argentina

Human action recognition from skeletal data is an important and active area of research in which the state of the art has not yet achieved near-perfect accuracy on many well- known datasets. In this paper, we introduce the Distribution of Action Movements Descriptor, a novel action descriptor based on the distribution of the directions of the motions of the joints between frames, over the set of all possible mo- tions in the dataset. The descriptor is computed as a normal- ized histogram over a set of representative directions of the joints, which are in turn obtained via clustering. While the descriptor is global in the sense that it represents the overall distribution of movement directions of an action, it is able to partially retain its temporal structure by applying a window- ing scheme. The descriptor, together with performs several state-of-the-art known datasets. a standard classifier, out- techniques on many well-

关键词： human action recognition descriptor Prob-SOM MSRC12 Action3D

Modulating the growth of cysteine-capped cadmium sulfide quantum dots with enzymatically produced hydrogen peroxide

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Nano Research 2017年第6期10卷 1932-1941页

作者： Ruta Grinyte Javier Barroso laura Saa Valeri Pavlov Biosensing Unit CIC BiomaGUNE Parque Tecnologico de San Sebastian Paseo Miramon 182 Donostia-San Sebastian 20014 Spain

Cysteine （CSH） readily stabilizes cadmium sulfide quantum dots （CdS QDs） that grow in aqueous buffered solutions. The oxidation of CSH by hydrogen peroxide （H202） at room temperature yields cystine （CSSC）, which is less efficient in stabilizing CdS QDs compared to CSH. Herein, we demonstrate that such oxidation causes a decrease in the formation rate of CSH-capped CdS QDs from Cd^2＋ and S^2- ions. For the first time, we combined the oxidation of CSH with the glucose oxidase （GOx）-assisted biocatalytic oxidation of D-glucose, which leads to a buildup of H2O2 in the reaction mixture. The enzymatically modulated in situ growth of CdS QDs was monitored using two techniques： fluorescence spectroscopy and photoelectrochemical （PEC） analysis. This system enables quantification of GOx and glucose in human serum.

关键词： quantum dots photoelectrochemistry enzyme fluorescence hydrogen peroxide

Environmental drivers of long-term variations in the abundance of the red hocicudo mouse (Oxymycterus rufus) in Pampas agroecosystems

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Integrative Zoology 2024年第1期19卷 37-51页

作者： laura Mariel CALFAYAN Regino CAVIA Jimena FRASCHINA Juan Santiago GUIDOBONO Irene laura GOROSITO María BUSCH Laboratorio de Ecología de Poblaciones Departamento de EcologíaGenética y EvoluciónFacultad de Ciencias Exactas y NaturalesUniversidad de Buenos Aires and Instituto de EcologíaGenética y Evolución de Buenos Aires(IEGEBA)Buenos AiresArgentina

During the 20th century,there has been an ongoing agricultural expansion and global warming,two of the main determinants influencing biodiversity changes in *** red hocicudo mouse(Oxymycterus rufus)inhabits subtropical grasslands and riparian habitats and has increased its abundance in recent years in central Argentina *** paper describes the long-term temporal changes in *** abundance in Exaltación de la Cruz department,Buenos Aires province,Argentina,in relation to weatherfluctuations and landscape features,as well as analyzes the spatio-temporal structure of captures of *** used generalized liner models,semi-variograms,the Mantel test,and autocorrelation functions for the analysis of rodent data obtained from trappings conducted between 1984 and *** showed an increase in abundance across the years of study,with its distribution depending on landscape features,such as habitat types and the distance *** rates showed a spatio-temporal aggregation,suggesting expansion from previously occupied *** was more abundant at lower minimum temperatures in summer,higher precipitation in spring and summer,and lower precip-itations in *** conditions affected *** abundance,but there was local variation that differed from global patterns of climate change.

关键词： agroecosystems climate change linear habitats Oxymycterus rufus rodent

Strength and stiffness reduction factors for infilled frames with openings

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Earthquake Engineering and Engineering Vibration 2014年第3期13卷 437-454页

作者： Luis D.Decanini laura Liberatore Fabrizio Mollaioli Department of Structural Engineering and Geothecnics "Sapienza" University of Rome

Framed structures are usually infilled with masonry walls. They may cause a significant increase in both stiffness and strength, reducing the deformation demand and increasing the energy dissipation capacity of the system. On the other hand, irregular arrangements of the masonry panels may lead to the concentration of damage in some regions, with negative effects; for example soft story mechanisms and shear failures in short columns. Therefore, the presence ofinfill walls should not be neglected, especially in regions of moderate and high seismicity. To this aim, simple models are available for solid infills walls, such as the diagonal no-tension strut model, while infilled frames with openings have not been adequately investigated. In this study, the effect of openings on the strength and stiffness of infilled frames is investigated by means of about 150 experimental and numerical tests. The main parameters involved are identified and a simple model to take into account the openings in the infills is developed and compared with other models proposed by different researchers. The model, which is based on the use of strength and stiffness reduction factors, takes into account the opening dimensions and presence of reinforcing elements around the opening. An example of an application of the proposed reduction factors is also presented.

关键词： infilled frames openings strength stiffness reduction factor

Stratospheric entry point for upper-tropospheric air within the Asian summer monsoon anticyclone

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Science China Earth Sciences 2017年第9期60卷 1685-1693页

作者： FAN QiuJun BIAN JianChun laura L.PAN Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China College of Earth Sciences University of Chinese Academy of Sciences Beijing 100049 China National Center for Atmospheric Research Boulder CO 80301 USA

The Asian summer monsoon(ASM) anticyclone isolates upper-tropospheric air within the interior of the anticyclone from the outside. Forward trajectory simulations in previous studies have shown that much of the air within the ASM anticyclone can be trapped for up to two or three weeks, not only laterally but also vertically. Here, we investigate the locations of exit points for upper-tropospheric air trapped within the ASM anticyclone, especially the preferred tropopause-crossing locations, using a 3-dimensional trajectory model. Forward trajectory calculations show two-thirds of the air crosses the tropopause at the southern part of the anticyclone via upward diabatic transport. Furthermore, some air crosses at northern and eastern parts via isentropic shedding, but air crosses rarely through the center of the anticyclone. However, calculations also show that many stratospheric parcels within the anticyclone are traceable from the upper-tropospheric anticyclone. This implies they cannot break through the tropopause directly overhead but instead enter the stratosphere via other entry points.

关键词： Asian summer monsoon anticyclone Tropopause Stratosphere-troposphere exchange Trajectory simulation

Red wine and green tea reduce H pylori- or VacA-induced gastritis in a mouse model

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World Journal of Gastroenterology 2007年第3期13卷 349-354页

作者： Paolo Ruggiero Giacomo Rossi Francesco Tombola laura Pancotto laura Lauretti Giuseppe Del Giudice Mario Zoratti Novartis Vaccines & Diagnostics s.r.l. Research Center SienaItaly Department of Veterinary Science University of Camerino Matelica Italy Department of Biomedical Sciences University of PadovaItaly CNR Institute of Neuroscience Section for Biomembranes Padova Italy CNR Institute of Neuroscience Section for Biomembranes Padova Italy

AIM： To investigate whether red wine and green tea could exert anti-H pylori or anti-VacA activity in vivo in a mouse model of experimental infection. METHODS： Ethanol-free red wine and green tea concentrates were administered orally as a mixture of the two beverages to H pylori infected mice, or separately to VacA-treated mice. Gastric colonization and gastric inflammation were quantified by microbiological, histopathological, and immunohistochemical analyses.RESULTS： In H pylori-infected mice, the red wine and green tea mixture significantly prevented gastritis and limited the localization of bacteria and VacA to the surface of the gastric epithelium. Similarly, both beverages significantly prevented gastric epithelium damage in VacA-treated mice; green tea, but not red wine, also altered the VacA localization in the gastric epithelium. CONCLUSION： Red wine and green tea are able to prevent H pylori-induced gastric epithelium damage, possibly involving VacA inhibition. This observation supports the possible relevance of diet on the pathological outcome of Hpylori infection.

关键词： VacA H pylori Gastritis Wine Tea Polyphenols

The concentration game: differential effects of bioactive signaling in 2D and3D culture

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Neural Regeneration Research 2016年第1期11卷 66-68页

作者： laura A.Smith Callahan The Vivian L.Smith Department of Neurosurgery & Center for Stem Cell and Regenerative Medicine University of Texas Health Science Center at Houston

Traumatic injuries to the central nervous system,such as traumatic brain injury,spinal cord injury and stroke,have a high prevalence,enormous financial costs and lack clinical treatments that restore neurological function（Ma et al.,2014）These injuries trigger a series of secondary biochemical and cellular responses that ultimately lead to cellular death and themaintenance of an unsupportive extracellular matrix （ECM） for tissue regeneration （Silva et al., 2014）. Artificial ECM or scaf- folds represent a way to alter this unsupportive environment to improve the efficacy of stem cell therapies and enhance neural tissue regeneration （Figure 1）.

关键词： bioactive injuries restore biochemical neurological traumatic signaling scaffold ultimately likely

Perspectives from a publishing ethics and research integrity team for required improvements

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Journal of Data and Information Science 2023年第3期8卷 1-14页

作者： Sabina Alam laura Wilson Publishing Ethics and Research Integrity Taylor and Francis GroupJournalsUK

It is imperative that all stakeholders within the research ecosystem take responsibility to improve research integrity and reliability of published *** on the unique experiences of a specialist publishing ethics and research integrity team within a major publisher,this article provides insights into the observed trends of misconduct and how those have evolved over time,and addresses key actions needed to improve the interface between researchers,funders,institutions and publishers to collectively improve research integrity on a global scale.

关键词： Research integrity Publishing ethics Training Education

REENGAGING THE LAND AT THE GEORGE *** PRESIDENTIAL CENTER

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Journal of Green Building 2014年第3期9卷 3-22页

作者： laura Solano Herb Sweeney IV Michael Van Valkenburgh Associates Landscape Architects Senior Associate Michael Van Valkenburgh AssociatesLandscape Architects

In planning the George *** Presidential Center in Dallas,Texas,former First Lady laura Bush presented a very clear vision of what the Center should epitomize:“Because George was the first president of the new millennium,I wanted it to be forward and modern.”1 For the president and *** this meant making the building and landscape environmentally responsible,beautiful,and *** particular,their love of native Texas landscapes was an important framework for transforming the project’s urban site into a park that was sustainable and experientially rich for *** was addressed from the start with smart planning that privileged contiguous parkland over impermeable surfaces and *** consideration of every landscape component—-stormwater,plants,soil,topography,and more—netted cohesive natural systems that are better able to succeed with short-term establishment and provide enduring long-term health,the ultimate goals for a sustainable landscape.

关键词： presidential libraries parks sustainable landscapes stormwater management cistern irrigation tank forebay bioswale native ecologies native plants prairies meadows planting soil Texas