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Land-use Changes Alter Energy and Water Balances on an African Brachiaria Pasture Replacing a Native Savanna in the Orinoco llanos

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Journal of Atmospheric Science Research 2019年第2期2卷 22-36页

作者： José San-José Rubén Montes Rafael Herrera Jair M. Maia Nina Nikonova Ecology Center Venezuelan Institute for Scientific ResearchAP 20632Caracas 1020-AVenezuela environment Studies departament Simón Bolívar UniversityAP 89000Caracas 1080-AVenezuela Escola Normal Superior Universidade do Estado do AmazonaManausBrazil

The seasonal changes in the energy balance after the substitution of a herbaceous savanna by a Brachiaria field located in the Orinoco lowlands were assessed over an entire year using the eddy covariance technique. Simultaneously, an herbaceous savanna was monitored as a control. This work provides evidence that the vegetation replacement lead to different patterns of energy and water balance. The seasonal trends of the latent heat flux (λE) to available energy (Ra) ratio tended to decrease as senescence increased due to seasonal influence of air humidity mole fraction deficit and soil water content on leaf area index (LAI) and surface conductance (gs). Therefore, the partitioning of the available energy depended on both climatological (i.e., solar radiation, volumetric soil water content and air humidity mole fraction deficit) and biological variables (i.e., conductance behavior and LAI) which were stress-induced. For the wet season, the seasonally averaged daily λE in the Brachiaria field (i.e., 0.8 ± 0.1 mm d^-1) was 1.3-fold higher than that in the herbaceous savanna (i.e., 0.6 ± 0.1 mm d-1)(Mann-Whitney U-test). For the dry season, the value was 2.7 ± 0.6 and 2.2 ± 0.4 mm d-1, respectively, these means values were not significantly different. In the Brachiaria and herbaceous savanna stands, the annual evapotranspiration was 731 and 594 mm year^-1, respectively, and the annual ratio of evapotranspiration to precipitation was 0.52 to 0.42 respectively. In Brachiaria field, the deep drainage was relatively lower (43% of total precipitation) than that in the herbaceous savanna stand (53%) leaving a similar amount of water to increase soil storage. The current shift in land cover decrease deep drainage and increased λE by water uptake from a pasture with high belowground phytomass and LAI.

关键词： Energy balance Seasonal effect Orinoco lowlands

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Means of Choice for Interactive Management of Dynamic Geometry Problems Based on Instrumented Behaviour

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American Journal of Computational Mathematics 2013年第3期3卷 41-51页

作者： Philippe R. Richard Michel Gagnon Josep Maria Fortuny Nicolas Leduc Michèle Tessier-Baillargeon departament de Didàctica de les Matemàtiques i de les Ciències Experimentals Universitat Autònoma de Barcelona Spain Département de didactique Université de Montréal Canada Département de génie informatique et génie logiciel école Polytechnique de Montréal Canada

Our paper presents a project that involves two research questions: does the choice of a related problem by the tutorial system allow the problem solving process which is blocked for the student to be restarted? What information about learning do related problems returned by the system provide us? We answer the first question according to the didactic engineering, whose mode of validation is internal and based on the confrontation between an a priori analysis and an a posteriori analysis that relies on data from experiments in schools. We consider the student as a subject whose adaptation processes are conditioned by the problem and the possible interactions with the computer environment, and also by his knowledge, usually implicit, of the institutional norms that condition his relationship with geometry. Choosing a set of good problems within the system is therefore an essential element of the learning model. Since the source of a problem depends on the student’s actions with the computer tool, it is necessary to wait and see what are the related to problems that are returned to him before being able to identify patterns and assess the learning. With the simultaneity of collecting and analysing interactions in each class, we answer the second question according to a grounded theory analysis. By approaching the problems posed by the system and the designs in play at learning blockages, our analysis links the characteristics of problems to the design components in order to theorize on the decisional, epistemological, representational, didactic and instrumental aspects of the subject-milieu system in interaction.

关键词： Didactics of Mathematics Competencies Geometric Thinking Tutorial System Related Problems Dynamic Geometry Instrumented Behavior Cognitive Interactions Conceptions Mathematical Work Space Means of Choice Didactic Contract

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Effects of the Orientation of the Mountainside, Altitude and Varieties on the Quality of the Coffee Beverage from the “Matas de Minas” Region, Brazilian Southeast

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American Journal of Plant Sciences 2016年第8期7卷 1291-1303页

作者： Williams P. M. Ferreira Daniel M. Queiroz Samuel A. Silvac Rafael Simões Tomaz Paulo C. Corrêa National Coffee Research Center Brazilian Corporation of Agricultural Research—EMBRAPA Vicosa Brazil departament of Agricultural Engineering Federal University of Vicosa—UFV Vicosa Brazil Department of Rural Engineering Federal University of Espirito Santo—UFES Alegre Brazil Department of Agronomy Engineering Faculdade de Ciencias Agrárias e Tecnológicas (FCAT) Sao Paulo State University—UNESP Dracena Brazil

Based upon qualitative parameters experiments, this study aims to investigate how the elements of the environment, where the coffee is produced, contribute to the final quality of the product. For the analyses, it was used approximately one kilogram of coffee cherry samples collected in 14 municipalities previously chosen on the East side of the Minas Gerais State, Brazil. The coffee cherry samples were collected and analyzed for each of the two varieties in four levels of altitude for each exposure side of the mountain in relation to the Sun. The quality of the coffee was evaluated through the analysis of its physical characteristics and sensory analysis, popularly known as "Test of drink or Cupping" carried out by three tasters that belonging to the group of Q-Graders, according to the rules of national and international competitions of the Brazilian Association of Special Coffees (BSCA). Were performed analysis by means descriptive statistics, analysis of variance and multivariate analysis, all of them aiming to study the individual sensory characteristics of quality of the coffee beverage from the “Matas de Minas” region. Path coefficient analysis also was carried out for the partition of the phenotypic correlation coefficients into measures of direct and indirect effects, in order to determine the individual sensory characteristics that played a major role in the beverage final score. The results demonstrate that it is not possible to conclusively establish the differences among coffees evaluated with basis on varieties and environmental factors previously cited. It can be concluded that it is not recommended to associate the quality of coffee only to a specific factor whether from the environment or being it a specific of the culture of coffee. However, the cafes that were evaluated had intrinsic quality, which were derived from the specific characteristics of the “Matas de Minas” region where they were grown.

关键词： Top Quality Coffee Mountain Coffee Coffee Cherry

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Efficacy of Glyphosate in Water Management and the Effects on Water Quality

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Journal of Water Resource and Protection 2020年第1期12卷 50-59页

作者： Evandro L. C. Souza José T. Filho Edivaldo D. Velini José R. M. Silva Kelly C. Tonello Luiz L. Foloni German D. D. Gonzalez Admilson C. Barbosa Thiago A. Freato School of Agricultural Engineering State University of Campinas Campinas Brazil Department of Plant Breeding an Protection College of Agricultural Sciences Sao Paulo State University Botucatu Brazi departament of environmental Sciences Federal University of São Carlos Sorocaba Brazil Empresa Metropolitana de águas e Energia S.A. (EMAE) São Paulo Brazil Center of Meteorological and Climate Researchers Applied to Agriculture State University of Campinas Campinas Brazil

The present work aimed to evaluate the behavior of glyphosate herbicide in aquatic environment, considering some water quality parameters, in reservoir conditions without flow and without replacement of evapotranspired water. Twenty reservoirs (polyethylene water tanks) with a storage capacity of 1000 liters were used. The recommended herbicide dose according to the manufacturer was 7.0 L or 3360 grams of acid equivalent per hectare. For application in the reservoirs, a precision equipment was used to carbon dioxide (CO2), providing a flow of 200 L·ha-1. Freezing macrophyte death was achieved by storing the plants in a freezer at -18°C for a period of 48 hours. The analyses of control efficiency were performed at 7, 14, 21, 28, 35 and 42 days after application (DAA). Water samples for analysis of quality indicators, pH and dissolved oxygen were collected weekly for nine weeks. The obtained result allows concluding that the herbicide glyphosate presented excellent control efficiency of water hyacinth and did not significantly alter the water quality parameters pH and dissolved oxygen, indicating its use in the management of this macrophyte.

关键词： Herbicide pH Dissolved Oxygen environmental Impact

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Water Hyacinth Control by Glyphosate Herbicide and Its Impact on Water Quality

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Journal of Water Resource and Protection 2020年第1期12卷 60-73页

作者： Evandro L. C. Souza José T. Filho Edivaldo D. Velini José R. M. Silva Kelly C. Tonello Luiz L. Foloni Admílson C. Barbosa Thiago A. Freato School of Agricultural Engineering State University of Campinas Campinas Brazil Department of Plant Breeding an Protection College of Agricultural Sciences Sao Paulo State University Botucatu Braz departament of environmental Sciences Federal University of São Carlos Sorocaba Brazil Empresa Metropolitana de águas e Energia S.A. (EMAE) São Paulo Brazil Center of Meteorological and Climate Researchers Applied to Agriculture State University of Campinas Campinas Brazil

The aim of this study was to evaluate the herbicide glyphosate under aquatic environment conditions, in a controlled and closed experimental field, in the management of water hyacinth (Eichhornia crassipes) in reservoirs. Twenty reservoirs (polyethylene water tanks) with storage capacity of 1000 liters were used, without water flow and without evapotranspired water replacement (worst case), being 04 for each treatment. The adult plants were placed in the water tanks to provide 90% surface occupation of the reservoir. Five treatments with four repetitions were considered, being: 1) Reservoir colonized by water hyacinth without control;2) Reservoir colonized by water hyacinth, controlled by glyphosate;3) Reservoir colonized by water hyacinth, controlled by freezing;4) Reservoir without water hyacinth and glyphosate application and 5) Reservoir without water hyacinth and no glyphosate application. The glyphosate herbicide was used at the highest recommended dose, 7.0 L·ha-1 or 3360 g of acid equivalent per ha, applied using carbon dioxide precision equipment (backpack sprayer), providing a flow rate of 200 L·ha-1. The water samples were collected at the time of application, 6, 12, 18 and 24 hours after application and also at 2, 4, 8, 16, 32 and 64 days after application, in the morning, always at the same time, also between 8 and 9 h. The method used for determination of residues was by high performance liquid chromatography (HPLC) and mass spectrometry with a mass selective detector. Low concentrations of glyphosate and aminomethylphosphonic acid (AMPA) were found in both reservoirs that received application of the product. The half-life of glyphosate in water to the reservoirs with water hyacinth was 11 days and in the reservoirs without water hyacinth was 21 days. The results show a low potential of environmental impact of glyphosate use in the control of water hyacinth in reservoirs.

关键词： Eichhornia crassipes Weed Control Herbicides environmental Impact

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Coefficient in Tomato Seedling Cultivated with Hydroretentor

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Journal of Agricultural Science and Technology(B) 2018年第8期8卷 507-511页

作者： Catariny Cabral Aleman Flávio Campos Bastos Agricultural Engineering departament Federal University of Vicosa Ph Rolfs Avenue s/n Campus Universitário Vicosa-MG 36572-028 Brazil

The objective of this study was to obtain the weekly crop coefficient (Kc) for tomato seedlings in substratum with waterproofing polymer and irrigated by automatic system of localized irrigation. The experiment was conducted in an agricultural greenhouse located in the irrigation experimental area of the Department of Agricultural Engineering, Vi?osa-MG, Brazil. The crop coefficient (Kc) for tomato seedlings was obtained for the conditions of the experiment (in plastic trays of 128 cells, in greenhouse, in Vi?osa-MG, for the spring/summer season), using the substrates with and without hydrogel. The irrigation system was micro sprinkler, consisting of four emitters per tray of seedlings, so that each tray constitutes an individualized experimental unit. The method for estimation of reference evapotranspiration was Penman-Monteith FAO56. The weighing lysimetry was used to obtain the variation of the tray mass from the evapotranspiration of the culture. Two consecutive daily weights, spaced at intervals of 60 min (during the morning shift), were performed for five sample units (SU) arranged in a completely randomized design in the greenhouse. Each SU was composed of a tray of 128 cells. The values of Kc obtained were used to calibrate the crop evapotranspiration (ETc) estimates used in the later stages. Weekly Kc values were generated. Irrigation was managed so that the crop did not undergo water stress during the moulting phase. For the conditions tested it was possible to obtain Kc values between 0.72 and 2.86 for the substrate without hydrogel and 0.81 to 3.46 for the substrate with hydrogel. It should be considered that the production stage of seedlings is very demanding in water and in protected environment conditions it is possible to obtain high Kc values.

关键词： Water need water economy automatic irrigation.

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Stages of care for patients with chronic hepatitis C at a hospital in southern Brazil

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世界肝病学杂志:英文版(电子版) 2023年第8期15卷 973-984页

作者： Manoela Badinelli Vaucher Camila Ubirajara Silva Ivana Rosângela Santos Varella Arthur Yu-Shin Kim Dimas Alexandre Kliemann Department of Hepatology Universidade Federal de Ciências da Saúde de Porto AlegrePorto Alegre 90050-170Rio Grande do SulBrazil Department of Medicine Universidade do Vale do TaquariLajeado 95914-014RSBrazil Department of Application and Monitoring of Injectable Drugs Hospital Sanatório PartenonPorto Alegre 90650-000RSBrazil Department of Epidemiology Hospital Nossa Senhora da ConceiçãoPorto Alegre 91350-200Rio Grande do SulBrazil Department of Infectious Diseases Massachusetts General HospitalBostonMA 02114United States Department of Medicine Harvard Medical SchoolBostonMA 02114United States departament of Infectious Diseases Hospital Nossa Senhora da ConceiçãoPorto Alegre 91350-200Rio Grande do SulBrazil

BACKGROUND Hepatitis C virus(HCV)is defined as a public health problem by the World Health Organization(WHO)and since then has defined targets through the HCV *** HCV cascade of care highlights the progress towards these goals and essential interventions that need to be delivered along this continuum *** To document the treatment cascade for patients with HCV infection at the Hospital Nossa Senhora da Conceição(HNSC),defining the percentage of antibody-positive patients who collected molecular biology tests(polymerase chain reaction),attended outpatient clinic assistance,underwent treatment,and achieved a virologic cure termed sustained virologic response(SVR).METHODS With the retrospective cohort design,patients diagnosed with HCV infection in the period between January 1,2015 and December 31,2020 were *** from HCV notification forms,electronic medical records,Computerized Laboratory environment Manager System,and Medicine Administration System(evaluation of special medications)were collected in 2022 and all information up to that period was *** data were analyzed with IBM SPSS version 25,and Poisson regression with robust simple variance was performed for analysis of variables in relation to each step of the *** with P<0.20 were included in the multivariate analysis with P<0.05 considered ***’s chi-square test was applied to compare the groups of patients who persisted in follow-up at the HNSC and who underwent follow-up at other *** Results were lower than expected by the WHO with only 49%of candidates receiving HCV treatment and only 29%achieving SVR,despite the 98%response rate to direct acting antivirals documented by follow-up *** city of origin and the place of follow-up were the variables associated with SVR and all other *** comparing the cascade of patients who remained assisted by the HNSC vs external patients,we observed superior data for HNSC patien

关键词： Cascade of care Elimination Hepatitis C virus Sustained virologic response

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