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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

Genetic testing vs microforceps biopsy in pancreatic cysts:Systematic review and meta-analysis

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World Journal of Gastroenterology 2019年第26期25卷 3450-3467页

作者： Sandra Faias luisa pereira Angelo luis Paula Chaves Marilia Cravo Department of Gastroenterology Instituto Portugues de Oncologia de Lisboa de Francisco GentilEPELisboa 1099-023Portugal Faculdade de Ciencias da Seude Universidade da Beira InteriorCovilha 200-506Portugal GRUBI-Grupo de Revisoes Sistematicas Universidade da Beira InteriorCovilha 6200-506Portugal Centro de Matemática e Aplicacoes(CMA-UBI) Universidade da Beira InteriorCovilha 6200-506Portugal Centro de Investigacao em Ciencias da Saude(CICS-UBI) Universidade da Beira InteriorCovilha 6200-506Portugal Department of Pathology Instituto Portugues de Oncologia de Lisboa de Francisco GentilEPELisboa 1099-023Portugal Department of Gastroenterology Hospital Beatriz AngeloLoures 2674-514Portugal Faculdade de Medicina Universidade de LisboaLisboa 1099-023Portugal

BACKGROUND Carcinoembryonic antigen(CEA)and cytology in pancreatic cystic fluid are suboptimal for evaluation of pancreatic cystic *** testing and microforceps biopsy are promising tools for pre-operative diagnostic improvement but comparative performance of both methods is *** To compare the accuracy of genetic testing and microforceps biopsy in pancreatic cysts referred for *** We performed a literature search in Medline,Scopus,and Web of Science for studies evaluating genetic testing of cystic fluid and microforceps biopsy of pancreatic cysts,with endoscopic ultrasound with fine-needle aspiration(EUSFNA)prior to surgery and surgical pathology as reference standard for *** evaluated the diagnostic accuracy for:1-benign cysts;2-mucinous low-risk cysts;3-high-risk cysts,and the diagnostic yield and rate of correctly identified cysts with microforceps biopsy and molecular *** also assessed publication bias,heterogeneity,and study *** Eight studies,including 1206 patients,of which 203(17%)referred for surgery who met the inclusion criteria were analyzed in the systematic review,and seven studies were included in the *** testing and microforceps biopsies were identical for diagnosis of benign *** analysis was superior for diagnosis of both low and high-risk mucinous cysts,with sensitivities of 0.89(95%CI:0.79-0.95)and 0.57(95%CI:0.42-0.71),specificities of 0.88(95%CI:0.75-0.95)and 0.88(95%CI:0.80-0.93)and AUC of 0.9555 and 0.92,*** diagnostic yield was higher in microforceps biopsies than in genetic analysis(0.73 vs 0.54,respectively)but the rates of correctly identified cysts were identical(0.73 with 95%CI:0.62-0.82 vs 0.71 with 95%CI:0.49-0.86,respectively).CONCLUSION Genetic testing and microforceps biopsies are useful second tests,with identical results in benign pancreatic *** analysis performs better for low-and high-risk cysts but has lower diagnos

关键词： Pancreatic cysts Endoscopic ultrasound Endoscopic ultrasound with fineneedle aspiration Genetic testing Microforceps biopsy Molecular analysis KRAS Carcinoembryonic antigen Cytology

Phosphorus fractions and sorption dynamics in the sediments of two Ca-SO4 water reservoirs in the central Argentine Andes

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International Journal of Sediment Research 2017年第3期32卷 442-451页

作者： José gabriel León Fernando luis Pedrozo Pedro Félix Temporetti Instituto Argentino de Nivología Glaciología y Ciencias Ambientales (IANIGLA)CCT Mendoza Departamento General de Irrigación Gobierno de Mendoza Espaa y Barcala Instituto de Investigaciones en Biodiversidad y Medio Ambiente (INIBIOMA) CONICET-Universidad Nacional del Comahue

Phosphorus（P） fractionation and sorption behavior were studied in the sediments of two calcium-sulfate(Ca-SO4: Ca2+170 mg L-1; SO42-400 mg L-1) water reservoirs in the southern central Argentine Andes-El Carrizal Reservoir（ECR）,which stratifies in summer and El Nihuil Reservoir（ENR）,which is vertically mixed throughout the year. Sediment size classes reflected the lithology of both basins and the reservoirs relative location: ECR（downstream from a valley adjacent to a mountain environment） had higher clay proportions while the sand fraction was more important in ENR（just next to a mountain environment）.In both reservoirs, the chemical composition revealed low alteration and calcium enrichment. Total P content was relatively high(1.1-1.6 mg P kg-1dry weight) as expected from the contribution of marine formations. P fractionation was dominated by Ca-P（ECR, 69% and ENR, 63%） followed by organic-P（23%）in summer-anoxic ECR and by iron/aluminum（Fe/Al）-P（27%） in oxic ENR. Batch experiments showed that sorption behavior in ECR had a typical Langmuir isotherm plot while in ENR that model fitted only at low dissolved P values(<5 mg PL-1) and co-precipitation evidence was observed at higher P concentrations. It is proposed that lower Fe/Al-P content in anoxic（ECR） vs. oxic（ENR） sediments results from the P released from iron-bound phosphorus due to sulfate reduction-ferrous sulfide formation in an anoxic environment. This condition should enable ECR sediments to adsorb P into fresh oxidized iron,and ENR sediments to co-precipitate P with calcium due to Fe/Al-P saturation, as observed in batch experiments. This paper constitutes the first description of phosphorus content and dynamics in reservoir sediments in arid central western Argentina, where water sulfate concentrations are naturally high due to basin lithology.

关键词： Reservoir Internal load Phosphorus binding Calcareous watershed Southern Central Andes

Disaster Journalism in Print Media:Analysis of the Top 10 Hydrogeomorphological Disaster Events in Portugal,1865–2015

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International Journal of Disaster Risk Science 2022年第4期13卷 521-535页

作者： Michele Nacif Antunes Susana da Silva pereira Joséluis Zêzere Adauto Emmerich Oliveira Postgraduate Program in Public Health(PPGSC) Federal University of Espírito SantoVitoriaEspírito Santo 29047-105Brazil Centre for Geographical Studies Institute of Geography and Spatial PlanningUniversidade de Lisboa1600-276 LisbonPortugal Associate Laboratory TERRA 1349-017 LisbonPortugal

Disaster communication guidelines emphasize that journalists should be aware of past major disasters and draw lessons from the coverage of those *** press is an important source for the evolution of historical disaster and risk research paradigms over *** study explored the top 10 damaging hydrogeomorphological events in Portugal selected from the disaster database,which includes events that caused human damages(fatalities,injured,missing,evacuated,and displaced)reported over a period of 151years(1865–2015)by the Portuguese newspaper Diário de Notícias(DN).News analysis was guided by the news *** analysis of the news published in DN enabled us to identify textual marks that present interconnections in the journalistic coverage and produce discursive standards for these *** textual marks were associated with the hazard and risk *** discursive standards of DN did not clearly reflect the ruptures in the hazard *** a rule,the journalistic reports contributed to the naturalization of disasters and the gap in public understanding of risks,by presenting an approach focused on relief actions—ignoring social issues,vulnerability,and population resilience—reducing the discourse of preparedness for future disasters.

关键词： Disaster journalism Hydrogeomorphological events News protocol Portugal Print media

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Spatial distribution of morphometric parameters of glacial cirques in the Central Pyrenees(Aran and Boí valleys)

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Journal of Mountain Science 2018年第10期15卷 2103-2119页

作者： luis LOPES Marc OLIVA Marcelo FERNANDES Paulo pereira Pedro PALMA Jesús RUIZ-FERNáNDEZ Centre for Geographical Studies – IGOT Universidade de Lisboa Department of Geography University of Barcelona Environmental Management Center Mykolas Romeris University Department of Geography University of Oviedo

Glacial cirques are typical landscape features of mid-latitude mountain environments like the Central Pyrenees. Their morphology as well as their spatial distribution provides insights about past glaciers and climates. In this study, we examine the distribution, morphometrical and topographical characteristics of glacial cirques in two U-shaped glacial valleys located in the Central Pyrenees – the Aran and the Boí valleys. They are located in different aspects of this mountain range(north vs south) under different climatic influences that promoted distinct glaciation patterns during the late Pleistocene. The spatial mapping of these landforms was carried out using high-resolution imagery and field observations. We analysed the data of the morphometrical and topographical variables of the glacial cirques by using different statistical and geospatial methods in order tounveil the factors controlling their formation and development. A total of 186 glacial cirques were mapped in the study area, including 119 in the Aran and 67 in the Boí valleys. The local topography and microclimate conditions lead to substantial differences in both areas in terms of the morphology and dimensions of the cirques. Glacial cirques in Boí are distributed at slightly higher elevations than in Aran and they are also larger, though their dimensions decrease with elevation in both valleys. Aran cirques are mostly oriented NE, while Boí landforms do not show any prevailing aspect. Even though lithology does not control the distribution of the glacial cirques, some specific lithological settings may favour the development of larger cirques. In general, glacial cirques in the Aran and the Boí valleys show morphometrical properties similar to those reported in other mid-latitude mountain ranges.

关键词： Central Pyrenees Aran and Boi valleys glacial cirques topography morphometry.

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Effect of climate and altitude on plant community composition and richness in Brazilian inselbergs

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Journal of Mountain Science 2020年第8期17卷 1931-1941页

作者： Herval Vieira PINTO-JUNIOR Pedro Manuel VILLA luis Fernando Tavares de MENEZES Miriam Cristina Alvarez pereira Universidade Federal de Vigosa Department of Plant BiologyLaboratory of Ecology and Evolution of Plants36570-900Vicosa-MGBrazil Universidade Federal de Vigosa Department of Forest EngineeringLaboratory of Forest Restoration36570-900Vicosa-MGBrazil Universidade Federal do Espirito Santo Department of Agrarian and Biological SciencesLaboratory of Ecology of Restinga and Mata Atlantica29932-900Sao Mateus-ESBrazil Universidade Federal do Espirito Santo Department of Biology29500-000Alegre-ESBrazil

Plant communities are shaped by multiple factors along environmental gradients;however,studies are limited on how environmental filtering drives community composition and species richness on tropical *** evaluate the influence of altitude and climatic variables related to temperature and precipitation on plant community composition and species richness on Brazilian *** assume as a premise that both climate and altitude would induce changes on plant community composition and species richness at the local *** used plant inventory data from 370 sampling units across four inselberg sites in the Atlantic Forest of Espírito Santo State,south-eastern *** tested the univariate and multivariate effects of altitude and climate variables on community composition and species richness with multiple *** in species richness between inselbergs were evaluated using sample-based data to estimate rarefaction and extrapolation *** addition,differences in species composition and taxonomic beta diversity were examined via novel frequency-based metrics.A contrasting climate pattern was observed between the inselberg sites,with south sites being wet compared to the dry conditions found in northern *** richness by rarefaction showed a similar pattern within regional sites;however,there were marked differences between *** richness and beta diversity showed significant differences among sites,with higher values in southern sites than in northern *** a multi-model comparison between inselberg sites,altitude significantly influenced community composition and species richness and explained more variance than climate *** finding suggested that climate could act to some extent on these tropical inselbergs;however,altitude was a better predictor of plant community composition and species richness at the local level.

关键词： Atlantic Forest Biome Beta diversity Abiotic filtering Climate models Environmental filtering Latitudinal gradient

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Online Learning Effectiveness in Times of Covid-19 for Utesa University Undergraduate Students in the Dominican Republic: A Narrative Research Approach

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Online Learning Effectiveness in Times of Covid-19 for Utesa...

作者： luis gabriel Pérez Báez 浙江师范大学

学位级别：硕士

Effectiveness refers to the measure of to what extent goals are accomplished,this study will focus on determining how effective online learning is,more specifically how it fares during times of COVID-19 pandemic and focused on undergraduate *** studies have been previously been made regarding online learning effectiveness,however there are not many studies referring to online learning in times of pandemic and even fewer focused on developing nations like the Dominican *** purpose of this study is to determine the effectiveness of online learning in times of COVID-19 of undergraduate students in the Dominican *** research is necessary because of how the country have switched completely,albeit temporarily to a fully online teaching modality due to COVID-19,this sudden change was done without much infrastructure,teaching materials or pacification previously adapted to this particular situation,therefore assessing how effective has online education has been during this period will contribute to the country’s current situation and any future challenge that may arrive and need a similar *** order to understand this problematic as well as to get useful information from the volunteers,undergraduate students from UTESA University,interviews will be used to collect information which will later be analyzed using the qualitative methodology with a narrative inquiry *** conducting this study is expected to provide much needed information in this subject that may serve as guidance for a future reform of the higher education system in the country,putting special focus on the online learning modality.

关键词： Effectiveness Online learning Undergraduate students COVID-19 Dominican Republic

Mapping ecosystem services in urban and peri-urban areas.A systematic review

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Geography and Sustainability 2024年第3期5卷 491-509页

作者： Paulo pereira Miguel Inácio luis Pinto Marius Kalinauskas Katarzyna Bogdzevic Wenwu Zhao Environmental Management Laboratory Mykolas Romeris UniversityVilniusLithuania State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Institute of Land Surface System and Sustainable Development Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China

Urban and peri-urban ecosystems are subjected to an intense *** demand for ecosystem services(ES)is higher in these ***,despite the anthropogenic pressures,urban and peri-urban ecosystems supply important *** is a crucial exercise to understand ES dynamics in these environments *** work aims to systematically review mapping ES in urban and peri-urban areas studies,following the Preferred Reporting Items for Systematic Reviews and Meta-alpha Methods.A total of 207 studies were *** results show increased work between 2011 and 2023,mainly conducted in Europe and *** work were developed in urban areas and did not follow an established ES *** studies focused on the ES supply dimension,the regulation and maintenance *** provisioning ES,most studies focused on Cultivating terrestrial plants for nutrition,regulating and maintainin g Atmospheric composition and conditions,and for cultural ES on Physical and experiential interactions with the natural *** methods were mostly applied following Indicator-based(secondary data:biophysical,socio-economic)*** few work validated the *** studies forecasted ES,primarily based on land use changes using CA-Markov *** study provides an overview of the most mapped urban and peri-urban ES globally,the areas where more studies need to be conducted,and the methods developed.

关键词： Systematic review Urban and peri-urban areas Ecosystem services Mapping Methods

A scoping review on the field validation and implementation of rapid diagnostic tests for vector-borne and other infectious diseases of poverty in urban areas

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Infectious Diseases of Poverty 2018年第1期7卷 879-896页

作者： Lyda Osorio Jonny Alejandro Garcia luis gabriel Parra Victor Garcia Laura Torres Stephanie Degroote Valery Ridde Epidemiology and Population Health Research Group School of Public HealthUniversidad del ValleCalle 4B No.36-00 Edif 118 Escuela de Salud PúblicaUniversidad del Valle Campus San FernandoCaliColombia School of Medicine Universidad del ValleCaliColombia University of Montreal Public Health Research Institute(IRSPUM) MontrealCanada French Institute for Research on Sustainable Development(IRD) Paris Descartes UniversityPopulation and Development Center(CEPED)UniversiteParis Sorbonne CiteNational Institute of Health and Medical Research(INSERM)HealthVulnerabilities and Gender Relations South(SAGESUD)ParisFrance

Background:Health personnel face challenges in diagnosing vector-borne and other diseases of poverty in urban *** is a need to know what rapid diagnostic technologies are available,have been properly assessed,and are being implemented to improve control of these diseases in the urban *** paper characterizes evidence on the field validation and implementation in urban areas of rapid diagnostics for vector-borne diseases and other diseases of *** body:A scoping review was ***-reviewed and grey literature were searched using terms describing the targeted infectious diseases,diagnostics evaluations,rapid tests,and urban *** review was limited to studies published between 2000 and 2016 in English,Spanish,French,and *** and exclusion criteria were refined post hoc to identify relevant literature regardless of study design and geography.A total of 179 documents of the 7806 initially screened were included in the ***(n=100)and tuberculosis(n=47)accounted for the majority of studies that reported diagnostics performance,impact,and implementation *** studies,assessing mainly performance,were identified for visceral leishmaniasis(n=9),filariasis and leptospirosis(each n=5),enteric fever and schistosomiasis(each n=3),dengue and leprosy(each n=2),and Chagas disease,human African trypanosomiasis,and cholera(each n=1).Reported sensitivity of rapid tests was variable depending on several ***,specificities were high(>80%),except for schistosomiasis and *** and implementation outcomes,mainly acceptability and cost,followed by adoption,feasibility,and sustainability of rapid tests are being evaluated in the *** to implementing rapid tests range from cultural to technical and administrative ***:Rapid diagnostic tests for vector-borne and other diseases of poverty are being used in the urban context with demonstrated impact on case ***

关键词： Communicable diseases Diagnostic services Point-of-care testing Field evaluation Sensitivity and specificity Implementation Evaluation studies Urban health