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Non-destructive microstructural analysis by electrical conductivity:Comparison with hardness measurements in different materials

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Journal of materials Science & Technology 2019年第3期35卷 360-368页

作者： Gon?alo L.Sorger J.P.Oliveira Patrick L.Inácio Norbert Enzinger pedro Vila? R.m.miranda Telmo G.Santos Department of Engineering Design and Production School of Engineering Aalto University Department of materials Science and Engineering The Ohio State University UNIDEmI Departamento de Engenharia Mecanica e Industrial Faculdade de Ciências e Tecnologia Universidade Nova de Lisboa ImAT-Institute of materials Science Joining and FormingTU Graz

The use of non-destructive evaluation(NDE) techniques for assessing microstructural changes in processed materials is of particular importance as it can be used to assess, qualitatively, the integrity of any material/structure. Among the several NDE techniques available, electrical conductivity measurements using eddy currents attract great attention owing to its simplicity and reliability. In this work, the electrical conductivity profiles of friction stir processed Ti6Al4 V, Cu, Pb, S355 steel and gas tungsten arc welded AISI 304 stainless steel were determined through eddy currents and four-point probe. In parallel, hardness measurements were also performed. The profiles matched well with the optical macrographs of the materials: while entering in the processed region a variation in both profiles was always observed. One particular advantage of electrical conductivity profiles over hardness was evident: it provides a better resolution of the microstructural alterations in the processed materials. moreover, when thermomechanical processing induces microstructural changes that modify the magnetic properties of a material,eddy currents testing can be used to qualitatively determine the phase fraction in a given region of the material. A qualitative relation between electrical conductivity measurements and hardness is observed.

关键词： Non-destructive evaluation techniques Electrical conductivity Hardness Friction stir processing Gas tungsten arc welding

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Anatomical features associated with venous congestion in DIEP flap using CT angiography with three-dimensional reconstruction

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Plastic and Aesthetic Research 2017年第8期4卷 127-134页

作者： Alejandro ruiz-moya Rafael-Antonio Lopez-Garcia Domingo Sicilia-Castro Tomas Gomez-Cia pedro Infante-Cossio Department of Plastic and Reconstructive Surgery Virgen del Rocio University Hospital41013 SevilleSpain Department of Surgery School of MedicineUniversity of Seville41009 SevilleSpain

Aim: Computed tomography angiography (CTA) using three-dimensional (3D) virtual reconstruction has been increasingly used in planning deep inferior epigastric artery perforator (DIEP) breast reconstruction. Although the most common complication associated with this surgery is diffuse venous congestion, its origin remains unclear. The aim of this study was to assess the anatomical characteristics of the anterior abdominal wall vessels that could predict venous congestion, using CTA with 3D virtual reconstruction. methods: A retrospective case-control study was conducted and a total of 169 DIEP flaps were reviewed. An abdominal CTA with 3D virtual reconstruction was analyzed with regard to anatomical features of the abdominal wall vessels. Seven venous congestive cases were identified. For each case, 3 controls that had not exhibited any vascular complications were randomly selected. Results: The global venous congestion rate was 4.14%. No statistically significant differences were found between the groups' superficial inferior epigastric vein (SIEV) diameter (P = 0.915), number of branches of SIEV (P = 0.371), number of perforators per flap (P = 0.255), flap subcutaneous tissue thickness (P = 0.652), direct communications between SIEV-perforators (P = 0.418), and communications of both SIEVs across the abdominal midline (P = 0.371). Conclusion: The present study provided new information concerning the identification of the controversial anatomical features associated with venous congestion in DIEP flaps. CTA and 3D virtual reconstruction were useful tools for evaluating the abdominal wall anatomy and for planning DIEP breast surgery, but neither for predicting nor preventing the diffuse congestive phenomenon.

关键词： Deep inferior epigastric artery perforator flap venous congestion breast reconstruction computed tomography angiography preoperative imaging virtual reality

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Characterization of the Topography and Wettability of English Weed Leaves and Biomimetic Replicas

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Journal of Bionic Engineering 2014年第3期11卷 346-359页

作者： pedro miguel matos Pereira Ana Sofia moita Gabriel Amaro monteiro Duarte miguel Franca Prazeres IBB - Institute for Biotechnology and Bioengineering Centre for Biological and Chemical Engineering Department of Bioengineering Instituto Superior Tecnico Universidade de Lisboa Av. Rovisco Pals 1049-001 Lisboa Portugal IN+ - Center for Innovation Technology and Policy Research Instituto Superior T~cnico Universidade de Lisboa Av. Rovisco Pais 1049-001 Lisboa Portugal

The topography and wettability of the underside of English weed （Oxalis pes-caprae） leaves and of their biomimetic replicas are investigated. Polyvinyl siloxane molds were cast from the leaves and then filled with an epoxy pre-polymer to produce replicas. The particular topographical structures of leaves and replicas were evaluated by optical microscopy and Scanning Electron microscopy （SEm） analysis. The static wettability of leaves and replicas was assessed by contact angle measurements, while the dynamic wettability was characterized by estimating contact angle hysteresis and studying the dynamic behavior of impacting water droplets. A smooth glass slip and its replica were used as control surfaces. The replica moulding method used was able to transfer the characteristic pattern of irregular 100 μm - 200 μm × 60 μm convex papillae interspersed with stomata of the original leaf to the epoxy replicas. The static contact angle of 143°± 3° and the contact angle hysteresis of 2~ indicate that the underside of the English weed leaf is close to superhydrophobic. The lower contact angles （130° ± 4°） and higher hysteresis （31°） observed for the replica when compared with the original leaves were associated to an inaccurate replication of the chemistry and structures of the three-dimensional wax projections covering the plant surface. Also, trichomes in the original leaves could not be accurately reproduced due to their flexibility and fragility. Differences in wetting behavior were also evident from droplet impact experiments, with rebound regimes prevailing in the original leaves and regimes characterized by higher adhesion and larger dissipation predominating in the replicas. Nevertheless, the morphological features of the leaf transferred to the replica were sufficient to promote a clear hydrophobic behavior of the replica when compared with the smooth epoxy reference surface.

关键词： biomimetic surfaces oxalis pes-caprae English weed replica molding wettability micro-topography

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eIF3 subunit m regulates blood meal digestion in Rhodnius prolixus affecting ecdysis, reproduction, and survival

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Insect Science 2023年第5期30卷 1282-1292页

作者： Pilar Ameijeiras Natalia Capriotti Sheila Ons pedro L.Oliveira marcos Sterkel Laboratorio de Neurobiología de Insectos(LNI) Centro Regional de Estudios GenómicosFacultad de Ciencias ExactasUniversidad Nacional de La PlataCENEXACONICETLa PlataBuenos AiresArgentina Instituto de Bioquímica médica Leopoldo de meis Universidade Federal do Rio de JaneiroRio de JaneiroBrazil Instituto Nacional de Ciência e Tecnologia em Entomologia molecular(INCT-Em) Rio de JaneiroBrazil

In triatomines,blood-feeding triggers many physiological processes including post embryonic development and *** feeding habits,such as hematophagy,can shape gene functions to meet the challenges of each type of *** gut of blood-sucking insects faces particular challenges after feeding due to the quantity and the quality of the food ingested.A comparison of transcriptomic and proteomic data indicates that post transcriptional regulation of gene expression is crucial in the triatomine *** was proposed that eukaryotic translation initiation factor 3 subunit m(eIF3m)and eIF3e define 2 different eIF3 complexes with a distinct affinity for the different mRNAs,thus selecting the set of mRNAs to be translated and constituting a post transcriptional mode of regulation of gene *** the eIF3m is mainly expressed in the gut,we evaluated its relevance in Rhodnius prolixus physiology through RNA interference-mediated gene *** knockdown of eIF3m reduced the digestion rate,affecting the processes triggered by a blood *** silencing inhibited molting and caused premature death in nymphs while impaired ovary development,oviposition and increased resistance to starvation in adult *** survival of males after feeding(resistance to starvation)was not affected by eIF3m *** information regarding the eIF3m function in insects is scarce and the phenotypes observed in *** upon eIF3m silencing are different and more severe than those previously described in Drosophila melanogaster,indicating a pleiotropic role of this gene in triatomines.

关键词： egg hatching hematophagous vectors lifespan oviposition post embryonic development starvation resistance

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Factors affecting the dominance hierarchy dynamics in a hummingbird assemblage

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Current Zoology 2019年第3期65卷 261-268页

作者： Ubaldo mARQUEZ-LUNA Carlos Lara Pablo CORCUERA pedro Luis VALVERDE Doctorado en Ciencias Biologicas y de la Salud Universidad Autonoma Metropolitana-lztapalapa Ciudad de Mexico Mexico Centro de Investigacion en Ciencia Biologicas Universidad Autonoma de Tlaxcala. Km 10.5 Autopista Tlaxcala-San Martin Texmelucan San Felipe Ixtacuixtla Tlaxcala Mexico Departamento de Biologia Universidad Autonoma Metropolitana-lztapalapa Ciudad de Mexico

Intra and in terspecific competiti on for n ectar play an imports nt role in hummingbird communities. Larger sized species usually exclude smaller species from the rich floral resources. However, it has been recently postulated that the competitive advantages of a large body size decline as the evolutionary distance between the contending species in creases. In this study, we analyzed dominance hierarchy dynamics in a hummingbird assemblage in central mexico. By monitoring hummingbird territories established in three plant species through 1 year, we assessed the effects of energy within territories and the territory owners identity in the frequency of inter and intraspecific encounters. We also evaluated if these factors affect the dominance of larger species when they compete against smaller distantly related contenders. Our results show that their frequency of intraspecific encounters was related with the identity of the territory's owner. On the contrary, the frequency of interspecific encounters was related with both the territory and the identity of the territory's owner. We did not find a significant difference between the number of encounters dominated by larger and smaller species and their conte nders. However, the in crease in genetic dista nee between contenders was positively associated with a higher frequency of encounters dominated by small *** results showed that the ecological factors and evolutionary relationships among contenders play important roles in the dominance hierarchy dynamics.

关键词： agonistic behavior competition hummingbirds resource quality territoriality

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Patterns of species richness and beta diversity of vascular plants along elevation gradient in Brazilian páramo

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山地科学学报(英文) 2023年第7期20卷 1911-1920页

作者： CORDEIRO Anais de Almeida Campos KLANDERUD Kari VILLA pedro manuel NERI Andreza Viana Federal University of Viçosa Department of Plant BiologyLaboratory of Ecology and Evolution of PlantsCampus Viçosa36570-900Viçosa-MGBrazil Faculty of Environmental Sciences and Natural Resource management Norwegian University of Life SciencesP.O.Box 5003N-1432ÅsNorway Biodiversity Conservation Association 7101Puerto AyacuchoEstado AmazonasVenezuela

Understanding the relationships between plant diversity and the environment is an important step towards conservation of species and *** this study,we hypothesize that community species richness decreases and species composition change along the elevation gradient,with a greater contribution of species turnover than nestedness to beta *** surveyed plant species in 300 plots(1 m×1 m)in four elevational bands(2100 m,2300m,2500 m,and 2700 m)in the CaparaóNational Park,Southeastern *** samples presented a great number of species(97 spp.,59 genera,27families),however,74%of the species were considered rare with their relative abundance beingmong the four bands along the gradient,we detected two distinct communities with few species in *** transition between the two communities occurred at 2500 m,and this elevation band also had the highest species richness in total.A non-metric multidimensional scaling(NmDS)showed floristic differences between the bands even though they had similar *** 89%of the plot pairs,using pairwise comparison of species composition,only half of the species that occurred in one did occur in the other *** dissimilarity among the plots and elevational band reflects a significant contribution of spatial species turnover to the species richness and beta diversity on the Caparaó*** diversity increased with spatial scale(from plot to elevational-band).The dissimilarity(βSOR=0.907)in the area was due almost exclusively to spatial species turnover(βSIm=0.879),with very low contribution of species nestedness(βSNE=0.028).Our research showed that species richness does not decrease with elevation in the study area,but the floristic composition *** clear distinction of species along the gradient show that spatial species turnover is the major diversitygenerating process in the studied area.

关键词： High altitude grassland Species turnover Partitioning diversity Campo de altitude Tropical mountains

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Successful eradication of the European rabbit(Oryctolagus cuniculus)and house mouse(mus musculus)from the island of Selvagem Grande(macaronesian archipelago),in the Eastern Atlantic

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Integrative Zoology 2010年第1期5卷 70-83页

作者： Paulo OLIVERA Dilia mENEZES Roger TROUT Alan BUCKLE pedro GERALDES JoséJESUS Parque Natural da madeira Quinta do Bom SucessoCaminho do MeioMadeira Forest Research Alice Holt LodgeFarnhamSurrey School of Biological Sciences The University of ReadingReadingUK University of madeira Department of BiologyCampus of PenteadaPortugal

The Portuguese island of Selvagem Grande(Great Salvage)in macaronesia is an important seabird breeding station in the eastern *** populations of Cory’s shearwater Calonectris diomedea(Scopoli,1769),Bulwer’s petrel Bulweria bulweria(Jardine&Selby,1828)and little shearwater Puffinus assimilis baroli(Bonaparte,1857)are present,and white-faced storm-petrel Pelagodroma marina(Latham,1790)and madeiran storm-petrel Oceanodroma castro(Harcourt,1851)populations are of global *** Grande also provides diverse habitats for an extensive flora,including 11 endemic *** 270-ha island was also inhabited by two alien invasive mammals:the European rabbit Oryctolagus cuniculus(Linnaeus,1758)and the house mouse mus musculus(Linnaeus,1758).Both are known to have had adverse impacts on breeding seabirds and island *** 2002,the Natural Park of madeira conducted a program using brodifacoum bait formulations aimed at rabbit and mouse *** 17000 individual baiting points were established on a 12.5×12.5 m *** were also applied by hand“seeding”on steep slopes and cliffs where bait stations could not be *** were removed after a ***,mice persisted for considerably longer and strategic bait applications against them continued for a further six *** assessments by trapping,bait takes and systematic observa-tion of signs over three years,has confirmed the removal of both alien invasive *** paper presents information on these operations,on measures adopted to mitigate adverse impacts of the eradication program on important vertebrate non-target species,including Berthelot’s pipit Anthus berthelotii Bolle,1862 and a species of gecko Tarentola bischoffi Joger,1984 and on the initial response of the island’s ecosystem to the eradication of rabbits and mice.

关键词： alien invasive island restoration mus musculus non-target mitigation Oryctolagus cuniculus

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Insecticidal Effects of the Annonaceous Acetogenin Squamocin and the Acetogenin Fraction of Seeds of <i>Rollinia occidentalis</i>on Soybean and Corn Pests

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Journal of Agricultural Chemistry and Environment 2014年第4期3卷 156-160页

作者： Diego Tolosa José ruiz Hidalgo pedro Eugenio Sal Susana Popich Alicia Bardón Adriana Neske Instituto de Química Orgánica Facultad de Bioquímica Química y Farmacia Universidad Nacional de Tucumán Ayacucho Argentina Universidad Nacional de Chilecito Chilecito Argentina INQUINOA-CONICET Tucumán Argentina

A treatment based on the acetogenin fraction of the methanol extract of Rollinia occidentalis seeds was applied to soybean crops for three consecutive years. In relation to the control population, the treatment reduced the population of Anticarsia gemmatalis, Rachiplusia nu, Pseudoplusia includens, Loxostege bifidalis and Spodoptera frugiperda to 52% and 65% after 48 h of application at concentrations of 500 and 750 μg/mL respectively, while low toxic effects were detected on natural enemies. The extract treatment at 500 μg/mL and a solution of the annonaceous acetogenin, squamocin, at 50 and 100 μg/mL, were also applied to a corn field to produce 75%, 93% and 100% mortality rates on the population of S. frugiperda, respectively, after 72 h of application. In addition, damages caused by lepidopterans in treated crops were lower than those observed in non treated fields, evaluated by residual biomass. This statement is based on data from trials with the commercially available insecticides lufenuron and cypermethrin.

关键词： Annonaceous Acetogenins Polyphagous Lepidopteran Soybean Crops Corn Crops Spodoptera frugiperda

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Ion dynamics into different pore size distributions in supercapacitors under compression

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Journal of Energy Chemistry 2023年第5期80卷 110-119,I0004页

作者： João pedro Aguiar dos Santos Cesar J.B.Pagan Rafael Vicentini Reinaldo F.Teófilo Renato Beraldo Leonardo m.Da Silva Hudson Zanin Brazilian Renewable Energies Center for Innovation on New EnergiesSchool of Electrical and Computer EngineeringUniversity of CampinasAv.Albert Einstein 40CampinasSP13083-852Brazil School of Electrical and Computer Engineering University of CampinasSP 13083-852Brazil multivariate Chemical Data Analysis Laboratory Department of ChemistryUniversidade Federal de Viçosa36570-900 ViçosaMGBrazil Department of Chemistry Laboratory of Fundamental and Applied ElectrochemistryFederal University of Jequitinhonha and Mucuri's ValleyRodovia MGT 367km 5835000 Alto da Jacuba39100-000DiamantinaMGBrazil

Compressing supercapacitor(SCs)electrode is essential for improving the energy storage characteristics and minimizing ions’distance travel,faradaic reactions,and overall ohmic *** comprising the ion dynamics in SC electrodes under compression are still ***,the ionic dynamics of five aqueous electrolytes in electrodes under compression were studied in this work for tracking electrochemical and structural changes under mechanical stress.A superionic state is formed when the electrode is compressed until the micropores match the dimensions with the electrolyte’s hydrated ion sizes,which increases the *** excessive compression is applied,the accessible pore regions decrease,and the capacitance ***,as the studied hydrated ions have different dimensions,the match between ion/pore sizes *** the LiOH and NaClO4electrolytes,increasing the pressure from 60 to 120 and 100 PSI raised the capacitance from 13.5 to 35.2 F g^(-1)and 30.9 to 39.0 F g^(-1),***,the KOH electrolyte with the lowest and LiCl with the biggest combination of hydrated ion size have their point of maximum capacitance(39.5 and 36.7F g^(-1))achieved at 140 and 80 PSI,*** LiCl and KCl electrolytes,overcompression causes a drop in capacitance higher than 23%.

关键词： mechanic compression Pore size distribution lon dynamics Activated carbon Supercapacitors

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A review of ecological impacts of global climate change on persistent organic pollutant and mercury pathways and exposures in arctic marine ecosystems

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Current Zoology 2015年第4期61卷 617-628页

作者： melissa A. mCKINNEY Sara pedro Rune DIETZ Christian SONNE Aaron T. FISK Denis ROY Bjorn m. JENSSEN Robert J. LETCHER Department of Natural Resources and the Environment University of Connecticut Storrs CT 06269 USA Center for Environmental Sciences and Engineering University of Connecticut Storrs CT 06269 USA Department of Bioscience Arctic Research Centre Aarhus University Roskilde DK-4000 Denmark Great Lakes Institute for Environmental Research University of Windsor Windsor ON N9B 3P4 Canada Department of Biology Norwegian University of Science and Technology Trondheim NO-7491 Norway Wildlife and Landscape Science Directorate Science and Technology Branch Environment Canada National Wildlife Research Centre Carleton University Ottawa ON K1A 0H3 Canada

Bioaccumulative and biomagnifying contaminants, such as persistent organic pollutants （POPs） and mercury （Hg）, have for decades been recognized as a health concern in arctic marine biota. In recent years, global climate change （GCC） and related loss of arctic sea ice have been observed to be driving substantial change in arctic ecosystems. This review summarizes findings documenting empirical links between GCC-induced ecological changes and alterations in POP and Hg exposures and pathways in arctic marine ecosystems. most of the studies have reported changes in POP or Hg concentrations in tissue in relation to GCC-induced changes in species trophic interactions. These studies have typically focused on the role of changes in abun- dance, habitat range or accessibility of prey species, particularly in relation to sea ice changes. Yet, the ecological change that re- suited in contaminant trend changes has often been unclear or assumed. Other studies have successfully used chemical tracers, such as stable nitrogen and carbon isotope ratios and fatty acid signatures to link such ecological changes to contaminant level variations or trends. Lower sea ice linked-diet changes/variation were associated with higher contaminant levels in some popula- tions of polar bears, ringed seals, and thick-billed murres, but the influence of changing trophic interactions on POP levels and trends varied widely in both magnitude and direction. We suggest that future research in this new area of GCC-linked ecotox- icology should focus on routine analysis of ancillary ecological metrics with POP and Hg studies, simultaneous consideration of the multiple mechanisms by which GCC and contaminant interactions can occur, and targeted research on changing exposures and toxicological effects in species known to be sensitive to both GCC and contaminants [Current Zoology 61 （4）： 617-628, 2015].

关键词： Climate change Ecological change Contaminants Trends Arctic marine ecosystems

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