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Dispersal of invasive species by drifting

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Current Zoology 2011年第6期57卷 818-827页

作者： m.C. VAN RIEL g. VAN deR VELde A. BIJ de VAATE Radboud University Nijmegen Institute for Water and Wetland Research Department of Animal Ecology and Ecophysiology Section Aquatic Animal Ecology Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands Team Freshwater Ecology DLO-Alterra P.O. Box 47 6700 AA Wageningen The Netherlands Netherlands Centre for Biodiversity Naturalis EO. Box 9517 2300 RA Leiden The Netherlands Waterfauna Hydrobiologisch Adviesbureau Oostrandpark 30 8212 AP Lelystad The Netherlands

Drifting can be an effective way for aquatic organisms to disperse and colonise new areas. Increasing connectivity between European large rivers facilitates invasion by drifting aquatic macroinvertebrates. The present study shows that high abundances of invasive species drift in the headstream of the river Rhine. Dikerogammarus villosus and Chelicorophium cur- vispinum represented up to 90% of the total of drifting macroinvertebrates. Drift activity shows seasonal and diel patterns. most species started drifting in spring and were most abundant in the water column during the summer period. Drift activity was very low during the winter period. Diel patterns were apparent; most species, including D. villosus, drifted during the night. Drifting macroinvertebrates colonised stony substrate directly from the water column. D. villosus generally colonised the substrate at night, while higher numbers of C. curvispinum colonised the substrate during the day. It is very likely that drifting functions as a disper- sal mechanism for crustacean invaders. Once waterways are connected, these species are no longer necessarily dependent on dispersal vectors other than drift for extending their distribution range

关键词： Amphipods Invaders Colonization Drift Daily rhythms Seasonal variation

On the friction and adhesion hysteresis between polymer brushes attached to curved surfaces: Rate and solvation effects

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Friction 2015年第2期3卷 148-160页

作者： Sissi de BEER g.DjuidjéKENmOÉ martin H.mÜSER materials Science and Technology of Polymers MESA+Institute for NanotechnologyUniversity of TwenteP.O.Box 2177500 AE Enschedethe Netherlands Jülich Supercomputing Centre Institute for Advanced Simulation FZ Jülich 52425 JülichGermany department of Physics Laboratory of Mechanics Faculty of ScienceUniversity of YaoundéP.O.Box 812YaoundéCameroon

Computer simulations of friction between polymer brushes are usually simplified compared to real systems in terms of solvents and *** most simulations,the solvent is only implicit with infinite compressibility and zero *** addition,the model geometries are parallel walls rather than curved or rough as in *** this work,we study the effects of these approximations and more generally the relevance of solvation on dissipation in polymer-brush systems by comparing simulations based on different solvation *** find that the rate dependence of the energy loss during the collision of brush-bearing asperities can be different for explicit and implicit ***,the non-Newtonian rate dependences differ noticeably between normal and transverse motion,i.e.,between head-on and off-center asperity ***,when the two opposing brushes are made immiscible,the friction is dramatically reduced compared to an undersaturated miscible polymer-brush system,irrespective of the sliding direction.

关键词： polymer brushes biomimetic materials molecular dynamics simulation

Wine residues extracts modulating in vitro metabolic syndrome

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Food Bioscience 2022年第6期50卷 1334-1340页

作者： Camila Rubia Christofoletti Annayara C.F.Fernandes Renata L.P.gandra Isabela m.martins Alessandra gambero gabriela A.macedo Juliana A.macedo School of Food Engineering Food and Nutrition DepartmentUniversity of Campinas (UNICAMP)CampinasSP13083-862Brazil Pontifícia Universidade Católica de Campinas (Centro de Ciências da Vida)CampinasSP13034685Brazil

metabolic syndrome is considered a worldwide epidemic health problem. The manifestations include obesity, dyslipidemias, elevation of arterial blood pressure, and insulin resistance. The wine waste is composed mainly of skin, seed and grape pomace, and is a source of phenolic compounds. Previous studies have demonstrated that grape phenolic compounds have antioxidants and anti-inflammatory properties, acting directly in the pathogenic process of several diseases. In order to improve the bioavailability and bioactivity of these compounds, enzymatic biotransformation reactions were *** aimed of this work was to evaluate whether phenolic extracts produced with wine waste by biotransformation with Tannase (tannin acyl hydrolase), were able to attenuate the metabolic syndrome manifestations like oxidative stress and reduce the inflammatory parameters in vitro *** different extracts were produced and the non-citotoxic concentrations of samples used (100, 200 and 500 μg/mL) were determined by mTT assay. The inflammatory response was induced in macrophages (RAW 264.7) culture using LPS (Lipopolysaccharide). The biotransformed extracts were able to reduce the TNF-α cell culture supernatant concentration by about 44%;and the IL-6 secretion was reduced by 82%. All the extracts demonstrate efficacy in reduction of intracellular reactive oxygen species (ROS) production and the same was observed for NO (nitric oxide) concentration in the cell culture supernatant after the administration of extracts. These results indicated the strong potential of employing phenolic wine waste extracts on the modulation of metabolic syndrome parameters, use that also brings environmental and socioeconomic advantages, since it brings an alternative for the use of residues.

关键词： Phenolic compounds Anti-inflammatory Tannase grape pomace Biotransformation

Recipes for the derivation of Water Quality Parameters Using the High-Spatial-Resolution Data from Sensors on Board Sentinel-2A,Sentinel-2B,Landsat-5,Landsat-7,Landsat-8,and Landsat-9 Satellites

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Journal of Remote Sensing

Journal of Remote Sensing 2023年第1期3卷 213-230页

作者： Juliana Tavora Binbin Jiang Thomas Kiffney guillaume Bourdin Patrick Clifton gray Lino Sander de Carvalho gabriel Hesketh Kristin m.Schild luiz Faria de Sousa Damian CBrady Emmanuel Boss Faculty of geo-Information Science and Earth Observation(ITC) University of TwentePO Box 2177500 AE EnschedeThe Netherlands State Key Laboratory of marine geology Tongji UniversityShanghaiChina School of marine Sciences University of MaineOronoMEUSA Nicholas School of the Environment Duke University Marine LabBeaufortNCUSA departamento de meteorologia Universidade Federal do Rio de JaneiroRio de JaneiroBrazil department of marine Sciences University of Southern MississippiOcean SpringMSUSA School of Earth and Climate Sciences University of MaineOronoMEUSA Climate Change Institute University of MaineOronoMEUSA

Satellites have provided high-resolution(<100 m)water color(i.e.,remote sensing reflectance)and thermal emission imagery of aquatic environments since the early 1980s;however,global operational water quality products ... 详细信息

Satellites have provided high-resolution(m)water color(i.e.,remote sensing reflectance)and thermal emission imagery of aquatic environments since the early 1980s;however,global operational water quality products based on these data are not readily available(e.g.,temperature,chlorophyll-a,turbidity,and suspended particle matter).Currently,because of the postprocessing required,only users with expressive experience can exploit these data,limiting their ***,we provide paths(recipes)for the nonspecialist to access and derive water quality products,along with examples of applications,from sensors on board Landsat-5,Landsat-7,Landsat-8,Landsat-9,Sentinel-2A,and *** emphasize that the only assured metric for success in product derivation and the assigning of uncertainties to them is via validation with in situ *** hope that this contribution will motivate nonspecialists to use publicly available high-resolution satellite data to study new processes and monitor a variety of novel environments that have received little attention to date.

关键词： environments Sentinel Spatial

A Note on Residue Formulas for the Euler Class of Sphere Fibrations

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Chinese Annals of mathematics,Series B 2011年第4期32卷 615-618页

作者： Francisco gómez RUIZ departamento de Algebra Geometría y Topología Universidad de Málaga Campus Universitario de Teatinos 29071 Málaga Spain

This paper presents a definition of residue formulas for the Euler class ot eohomology-oriented sphere fibrations ε. If the base of ε is a topological manifold, a Hopf index theorem can be obtained and, for the smoo... 详细信息

关键词： Euler class Sphere fibration Hopf index theorem Residue formulas

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Advances in manufacturing 2016年第4期4卷 287-295页

作者： g. Buffa m. de Lisi E. Sciortino L. Fratini epartment of Chemical Management Computer and Mechanical Engineering University of Palermo Viale delle Scienze 90128 Palermo Italy

Dissimilar stir welding （FSW） lap joints were produced by friction out of Ti6A14V titanium alloy and AA2024 aluminum alloy sheets. The joints, welded with varying tool rotation and feed rate, were studied by ana- lyzing the maximum shear strength, Vickers microhardness and optical observations. A dedicated numerical model, able to take into account the presence of the two different alloys, was used to highlight the effects of the process parameters on temperature distribution, strain distribution, and material flow. The combined analysis of experimental measurements and numerical predictions allowed explaining the effects of tool rotation and feed rate on the material flow. It was found that tool rotation had a larger impact on the joint effectiveness with respect to feed rate. A competition between material mixing and heat input occurs with increasing tool rotation, resulting in higher joint strength when lower values of tool rotation are used.

关键词： Finite element method (FEm) Ti6A14V AA2024 Friction stir welding (FSW) Lap joint

Proximal sensor-enhanced soil mapping in complex soil-landscape areas of Brazil

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Pedosphere 2021年第4期31卷 615-626页

作者： Sérgio H.g.SILVA David C.WEINDORF Wilson m.FARIA Leandro C.PINTO michele D.mENEZES luiz R.g.gUILHERmE Nilton CURI department of Soil Science Federal University of LavrasLavras 37200-000(Brazil) department of Earth and Atmospheric Sciences Central Michigan UniversityMount Pleasant 48858(USA)

Portable X-ray fluorescence(pXRF) spectrometry and magnetic susceptibility(mS) via magnetometer have been increasingly used with terrain variables for digital soil mapping. However, this methodology is still emerging in many countries with tropical soils. The objective of this study was to use proximal soil sensor data associated with terrain variables at varying spatial resolutions to predict soil classes using the Random Forest(RF) algorithm. The study was conducted on a 316-ha area featuring highly variable soil classes and complex soil-landscape relationships in minas gerais State, Brazil. The overall accuracy and Kappa index were evaluated using soils that were classified at 118 sites, with 90 being used for modeling and 28 for validation. Digital elevation models(dems) were created at 5-, 10-, 20-, and 30-m resolutions using contour lines from two sources. The resulting dems were processed to generate 12 terrain variables. Total Fe, Ti, and SiO_(2) contents were obtained using pXRF, with mS determined via a magnetometer. Soil class prediction was performed using the RF algorithm. The quality of the soil maps improved when using only the five most important covariates and combining proximal sensor data with terrain variables at different spatial resolutions. The finest spatial resolution did not always provide the most accurate maps. The high soil complexity in the area prevented highly accurate predictions. The most important variables influencing the soil mapping were mS, Fe, and Ti. Proximal sensor data associated with terrain information were successfully used to map Brazilian soils at variable spatial resolutions.

关键词： magnetic susceptibility magnetometer portable X-ray fluorescence spectrometer soil class soil spatial analysis spatial resolution terrain variables

Raman scattering study of the phonon dispersion in twisted bilayer graphene

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Nano Research 2013年第4期6卷 269-274页

作者： Jessica Campos-delgado luiz g. Cangado Carlos A. Achete Ado Jorio Jean-Pierre Raskin Institute of Information and Communication Technologies Electronics andApplied Mathematics (ICTEAM) Universite catholique de Louvain Louvain-la-Neuve 1348 Belgium departamento de Fisica Universidade Federal de Minas Gerais Belo Hofizonte MG 30123-970 Brazil Divisao de metrologia de materiais Instituto Nacional de Metrologia Qua/Made e Tecnologia (INMETRO) Xerem RJ 25250-020 Brazil

Bilayer graphene with a twist angle O between the layers generates a superlattice structure known as a moir6 pattern. This superlattice provides a O-dependent q wavevector that activates phonons in the interior of the Brillouin zone. Here we show that this superlattice-induced Raman scattering can be used to probe the phonon dispersion in twisted bilayer graphene （tBLg）. The effect reported here is different from the widely studied double-resonance in graphene-related materials in many aspects, and despite the absence of stacking order in tBLg, layer breathing vibrations （namely ZO＇ phonons） are observed.

关键词： twisted bilayer graphene Raman spectroscopy phonon branches

A comprehensive study on the processing of Co:ZnO nanostructured ceramics:defect chemistry engineering and grain growth kinetics

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Journal of materials Science & Technology 2023年第7期138卷 221-232页

作者： R.T.da Silva J.m.morbec g.Rahman H.B.de Carvalho Universidade Federal de Ouro Preto-UFOP Ouro PretoMG 35400-000Brazil School of Chemical and Physical Sciences Keele UniversityKeele ST55BGUnited Kingdom department of Physics Quaid-i-Azam UniversityIslamabad 45320Pakistan Universidade Federal de Alfenas-UNIFAL Alfenas 37130-000Brazi

In this report,we present a systematic study on the preparation of Co:ZnO ceramics via a standard solid-state route from different Co precursors(Co_(3)O_(4),CoO,and metallic Co)and atmospheres(O_(2)and Ar).Particular emphasis is given to defect chemistry engineering and the sintering growth ***-principles calculations based on density functional theory are employed to determine the formation en-ergy of the main point defects in ZnO and Co:ZnO *** on the theoretical results,a set of chemical reactions is *** microstructural characterization is also performed to determine the degree of Co incorporation into the ZnO *** samples prepared in Ar atmosphere and metal-lic Co present the highest Co solubility limit(lower apparent Co incorporation activation energy)due to the incongruent ZnO *** of the parameters of the sintering growth kinetics reveals that Co_(3)O_(4)is the best sintering additive to achieve larger grain sizes,and possible higher densi-ties,in both sintering atmospheres,while metallic Co is the best to achieve the smallest grain size with higher Co concentration and homogeneous spatial distribution for a subsequent reduction of *** results show that the sintering in O_(2)effectively promotes zinc vacancies in the ZnO structure,while the sintering in Ar promotes zinc interstitial *** findings contribute to understanding the preparation of Co-doped ZnO ceramics and the sintering growth kinetics,which may improve the state of the art in processing the material at both bulk and nanometric scales.

关键词： multifunctionality Zinc oxide defect engineering growth kinetics