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Root proliferation in native perennial grasses of arid Patagonia,Argentina

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Journal of Arid Land 2014年第2期6卷 195-204页

作者： Yanina A TORRES carlos A BUSSO Oscar A MONTENEGRO Leticia ITHURRART Hugo D GIORGETT gustavo RODRíGUEZ Diego BENTIVEGNA Roberto E BREVEDAN Osvaldo A FERNáNDEZ María M MUJICA Sandra S BAIONI José ENTíO María N FIORETTI Guillermo TUCAT Agronomy Department National University of the South and CERZOS (CONICET) Experimental Farm EEA INTA Patagones Ministery of Agrarian Issues Faculty of Agrarian Sciences National University of La Plata

Pappophorum vaginatum is the most abundant C4 perennial grass desirable to livestock in rangelands of northeastern Patagonia, Argentina. We hypothesized that （1） defoliation reduce net primary productivity, and root length density and weight in the native species, and （2） root net primary productivity, and root length density and weight, are greater in P. vaginatum than in the other, less desirable, native species （i.e., Aristida spegazzinfi, A. subulata and Sporobolus cryptandrus）. Plants of all species were either exposed or not to a severe defoliation twice a year during two growing seasons. Root proliferation was measured using the cylinder method. Cylindrical, iron structures, wrapped up using nylon mesh, were buried diagonally from the periphery to the center on individual plants. These structures, initially filled with soil without any organic residue, were dug up from the soil on 25 April 2008, after two successive defoliations in mid-spring 2007. During the second growing season （2008-2009）, cylinders were destructively harvested on 4 April 2009, after one or two defoliations in mid- and/or late-spring, respectively. Roots grown into the cylinders were obtained after washing the soil manually. Defoliation during two successive years did reduce the study variables only after plants of all species were defoliated twice, which supported the first hypothesis. The greater root net primary productivity, root length den- sity and weight in P. vaginatum than in the other native species, in support of the second hypothesis, could help to explain its greater abundance in rangelands of Argentina.

关键词： Aristida species competitive ability Pappophorum vaginatum Sporobolus cryptandrus warm-season perennial grasses

About an Ambiguity Appearing on the Hamiltonian Formulation of Quantum Mechanics

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Journal of Applied Mathematics and Physics 2018年第6期6卷 1382-1387页

作者： gustavo V. López Ana Griselda carlos R. Martínez-Prieto Departamento de Física Universidad de Guadalajara Guadalajara Mexico

We study classical and quantum dynamics of the symmetric harmonic oscillator and the symmetric bouncer defined in 2-D. For these systems we get each of them for two different constants of motion, two Lagrangians and two Hamiltonians which describe the same classical dynamics. However, the quantization of these systems (using Schrödinger equation), using their two equivalents Hamiltonian, describes different quantum dynamics for each of them. This represents an ambiguity on the Hamiltonian formulation of the Quantum Mechanics.

关键词： Harmonic Oscillator Quantum Bouncer Ambiguities in Quantum Mechanics Theory

Short and Long-Term Time Series Forecasting Stochastic Analysis for Slow Dynamic Processes

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Applied Mathematics 2019年第8期10卷 704-717页

作者： Julián Pucheta carlos Salas Martín Herrera Cristian Rodriguez Rivero gustavo Alasino FCEFyN-Universidad Nacional de Córdoba Córdoba Argentina FTyCA-Universidad Nacional de Catamarca Catamarca Argentina Cristian University of California Los Angeles USA Universidad Torcuato Di Tella Buenos Aires Argentina

This paper intends to develop suitable methods to provide likely scenarios in order to support decision making for slow dynamic processes such as the underlying of agribusiness. A new method to analyze the short- and long-term time series forecast and to model the behavior of the underlying process using nonlinear artificial neural networks (ANN) is presented. The algorithm can effectively forecast the time-series data by stochastic analysis (Monte Carlo) of its future behavior using fractional Gaussian noise (fGn). The algorithm was used to forecast country risk time series for several countries, both for short term that is 30 days ahead and long term 350 days ahead scenarios.

关键词： Stochastic Analysis Time Series Forecasting Decision Making Dynamic Process Process Modelling

Use of the SPAD-502 in Estimating Nitrogen Content in Leaves and Grape Yield in Grapevines in Soils with Different Texture

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American Journal of Plant Sciences 2012年第11期3卷 1546-1561页

作者： gustavo Brunetto gustavo Trentin carlos Alberto Ceretta Eduardo Girotto Felipe Lorensini Alcione Miotto Glaucia Regina Zaferi Moser George Wellington de Melo Department of Rural Engineering Program in Agricultural EcosystemsUniversidade Federal de Santa Catarina(UFSC)Flori-anopolisBrazil Embrapa Pecuária Sul BagéBrazil Program in Soil Science Departamento de Solos(DS)Universidade Federal de Santa Maria(UFSM)Santa MariaBrazil Embrapa Uva e Vinho Bento GoncalvesBrazil

The SPAD reading may be used in estimating total nitrogen content (N) in leaves and even in estimating grape yield in grapevines. The objective of this study was to estimate total N content in leaves and grape yield using the SPAD-502 in grapevines submitted to nitrogen fertilization in soils with clayey and sandy texture. In 2008, two experiments were installed in the Southern region of Brazil. In experiment 1, Cabernet Sauvignon grapevines were planted in a soil with clayey texture and with application of 10, 20, 40 and 80 kg·N·ha-1·year-1. In experiment 2, Cabernet Sauvignon grapevines were planted in a soil with sandy texture and with the application of 0, 10, 15, 20, 40, 80 and 120 kg·N·ha-1·year-1. In the grapevines of the two experiments and during the period from 2008 to 2010, SPAD readings were made on leaves throughout the flowering period and at change in color of the berries using the portable chlorophyll meter Minolta-SPAD-502. The leaves were collected, dried, ground and submitted to analysis of the total N content. In addition, grape yield per hectare was evaluated. The SPAD-502 readings estimated the total N content in flowering and at change in color of the berries in the Cabernet Sauvignon grapevines grown on soils with clayey texture and sandy texture, especially in the first year of evaluation. However, the precision of the SPAD-502 readings is low, with there being no relationship between the SPAD-502 readings and grape yield.

关键词： SPAD-Readings Non Destructive Estimation Foliar Nitrogen Leaf Analysis Vitis vinifera

Hydrolysis of Banana Tree Pseudostem and Second-Generation Ethanol Production by Saccharomyces Cerevisae

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Journal of Environmental Science and Engineering(A) 2013年第1期2卷 65-69页

作者： Luiz carlos Goncaives Filho gustavo Alexandre Achilles Fischer Noeli Sellin Cintia Marangoni Ozair Souza Masters Program in Process Engineering University of the Region of Joinville-Univille Joinville 89200-000 Brazil Department of Chemical Engineering University of the Region of Joinville-Univille Joinville 89200-000 Brazil

The alcoholic fermentation of substrates rich in free soluble sugars is well known and has been industrially developed. However, the production of second-generation ethanol from lignocellulosic biomass, which is abundantly available worldwide, remains under development. The aim of this study was to evaluate the possibility of using the Musa cavendischii banana tree pseudostem as a substrate for alcoholic fermentation. Hydrolisis methods using dilute sulfuric acid （1% and 2% H2SO4; 15 and 30 min; 90 ℃, 100 ℃ and 120 ℃） and enzymes （pH 5.5; and 45 ℃ for 24 h reaction time） were evaluated both separately and in combination. The effect of chemical pre-treatment of the substrate using 1% and 3% m/m NaOH （120 ℃, 15 min） was verified for both methods. The highest yield coefficient of fermentable sugars from dry biomass （Yrs = 74%） was obtained using enzymatic hydrolysis and pre-treatment with 3% NaOH. Using acid hydrolysis, the maximum yield obtained was 22% （1% H2SO4, 120 ℃, 30 min）. Fermentation of the hydrolysates was satisfactory, and the maximum yield of ethanol formed per unit of substrate consumed, total productivity and efficiency values were 0.35 g, 0.90 g ethanol L^-1·h^-1 and 65.9%, respectively. This demonstrates the utility of banana tree pseudostems in second-generation ethanol production.

关键词： Bioethanol biofuel biomass saccharification agricultural waste

Antioxidant effects of Phyllanthus niruri tea on healthy subjects

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Asian Pacific Journal of Tropical Medicine 2014年第2期7卷 113-118页

作者： Elisngela Colpo carlos D.D.A.Vilanova Romaiana P.Pereira Luis gustavo B.Reetz Liline Oliveira Iria L.G.Farias Aline A.Boligon Margareth L.Athayde Joo Batista T.Rocha Departamento de Química Centro de Ciências Naturais e ExatasUniversidade Federal de Santa Maria(UFSM) Laboratrio de Anlises Clínicas Hospital UniversitrioUniversidade Federal de Santa Maria(UFSM) Departamento de Farmcia Industrial Universidade Federal de Santa Maria(UFSM)

Objective:To investigate the potential antioxidant effects of Phyllanthus niruri(***)tea on healthy ***:Five non-smoking,male healthy volunteers,20 to 31 years *** *** subject was treated twice,following a randomized crossover fashion regarding the ingestion of *** infusion(5 g/750 mL)(tea group)or 750 mL of water(control group).Fasting venous blood samples were collected prior to and at 1.2 and 4 h after infusion *** were tested for plasmatic gallic acid and ascorbic acid levels,erythrocytic catalase and superoxide dismutase activities,and intracellular DCFH fluorescence in granulocytes,monocytes and ***:Catalase and superoxide dismutase activities were not altered by tea *** levels of gallic acid were significantly increased at1,2 and 4 h after *** ingestion and plasma ascorbic acid at 1 h after *** ***:Ingestion of *** tea is associated with a slight increase in antioxidant markers in human blood(ascorbic acid and gallic acid),which may contribute to its pharmacological effects.

关键词： Antioxidants Polyphenols Phyllanthus niruri Human Ascorbic acid Gallic acid

Meteorological indicators of dengue epidemics in non-endemic Northwest Argentina

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Infectious Disease Modelling 2022年第4期7卷 823-834页

作者： Javier Armando Gutierrez Karina Laneri Juan Pablo Aparicio gustavo Javier Sibona Departamento de Física-FCE-Universidad Nacional de Salta SaltaArgentina Grupo de Física Estadística e Interdisciplinaria CONICETCentro Atòmico Bariloche-CNEASan Carlos de BarilocheRío NegroArgentina Instituto de Investigaciones en Energía no Convencional(INENCO)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)-Universidad Nacional de Salta Av.Bolivia 51004400SaltaArgentina Simon A.Levin Mathematical Computational and Modeling Sciences Center Arizona State UniversityPO Box 871904TempeAZ85287-1904USA IFEG-CONICET and Fa.M.A.F.-Universidad Nacional de Cordoba CordobaArgentina

In the last two decades dengue cases increased significantly throughout the world,giving place to more frequent outbreaks in Latin *** the non-endemic city of San Ramòn de la Nueva Orán,located in Northwest Argentina,large dengue outbreaks alternate with several years of smaller *** pattern,as well as the understanding of the underlying mechanisms,could be essential to design proper strategies to reduce epidemic *** develop a stochastic model that includes climate variables,social structure,and mobility between a non-endemic city and an endemic *** variables were input of a mosquito population ecological model,which in turn was coupled to a meta-population,spatially explicit,epidemiological *** mobility was included into the model given the high border crossing to the northern country of Bolivia,where dengue transmission is sustained during the whole *** tested different hypotheses regarding people mobility as well as climate variability by fitting numerical simulations to weekly clinical data reported from 2009 to *** assessing the number of imported cases that triggered the observed outbreaks,our model allows to explain the observed epidemic *** found that the number of vectors per host and the effective reproductive number are proxies for large *** proxies are related with climate variability such as rainfall and temperature,opening the possibility to test these meteorological variables for forecast purposes.

关键词： Mathematical modelling Dengue Outbreak Mosquitoes population

Climatological Hydric Balance and the Trends Analysis Climatic in the Region of Machado in Minas Gerais State,Brazil

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American Journal of Climate Change 2018年第4期7卷 558-574页

作者： gustavo Souza Rodrigues Fernando Ferrari Putti Antonio carlos da Silva Alisson Souza de Oliveira Luís Roberto Almeida Gabriel Filho Jose Rosário Vellano University(UNIFENAS) AlfenasBrazil Machado Higher Education and Research Center(CESEP) MachadoBrazil Paulista State University Júlio de Mesquita Filho(UNESP) BotucatuBrazil

Lately the planet’s climate has been constantly changing, caused mainly by global warming which has exposed a great deal of concern to the population over the years. In order to understand the possible impacts that such changes may have on the environment and society in general, the importance of the analysis of climate and hydrological events trends and their performance in a region is justified. The objective of the present work was to perform the climatic classification and to evaluate the behavior of the Climatological Hydric Balance—CHB, from the region of Machado state of Minas Gerais—MG, taking into account a historical series of 55 years of climatic season data of the National Institute of Meteorology—INMET;to verify the occurrence of climatic changes by the temporal trends of precipitation and the average temperature, using the Mann-Kendall and Pettitt method;and the influence of these possible climate changes on CHB behavior and on the region’s climate classification. Based on the results found it verified the increase in the water deficit between the months of June to September and a reduction in the water surplus from November to February. By means of the trend analysis, there was a positive trend of increase in the average temperature of 1.6°C until the year 2100. The continuity and occurrence of these trends may have impacts on the economy, agriculture, the hydrological cycle, and consequently on the fauna, the flora and the population.

关键词： Climatic Series Global Warming IPCC

Apolipoprotein E polymorphism influences orthotopic liver transplantation outcomes in patients with hepatitis C virus-induced liver cirrhosis

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World Journal of Gastroenterology 2021年第11期27卷 1064-1075页

作者： José carlos Rodrigues Nascimento Lianna C Pereira Juliana Magalhães C Rêgo Ronaldo P Dias Paulo Goberlânio B Silva Silvio Alencar C Sobrinho gustavo R Coelho Ivelise Regina C Brasil Edmilson F Oliveira-Filho James S Owen Pierluigi Toniutto Reinaldo B Oriá Department of Anesthesia and Surgery Liver Transplantation Fortaleza General HospitalFortaleza 60150-160CEBrazil Laboratory of the Biology of Tissue Healing Ontogeny and NutritionDepartment of Morphology and Institute of BiomedicineSchool of MedicineFederal University of CearáFortaleza 60430-270CEBrazil Department of Dental Clinic Federal University of CearáFortaleza 60430-270CEBrazil Department of Surgery Liver Transplant Unit of Federal University of CearáFortaleza 60430-270CEBrazil Transplantation Division Hospital Geral de FortalezaFortaleza 60175-742CEBrazil Institute of Virology CharitéUniversitätsmedizin BerlinBerlin 10117Germany UCL Medical School Royal Free CampusLondon NW32PFUnited Kingdom Department of Specialized Medicine Hepatology Liver Transplantation UnitAzienda Sanitaria Universitaria Integrata of UdineUdine I-33100Italy

BACKGROUND Hepatitis C virus(HCV)infection is responsible for a chronic liver inflammation,which may cause end-stage liver disease and hepatocellular *** E(protein:ApoE,gene:APOE),a key player in cholesterol metabolism,is mainly synthesized in the liver and APOE polymorphisms may influence HCV-induced liver *** To determine whether APOE alleles affect outcomes in HCV-infected patients with liver cirrhosis following orthotopic liver transplantation(OLT).METHODS This was a cohort study in which 179 patients,both genders and aged 34-70 years,were included before or after(up to 10 years follow-up)*** injury severity was assessed using different criteria,including METAVIR and models for endstage liver *** polymorphisms were analyzed by quantitative real-time polymerase chain *** The APOE3 allele was the most common(67.3%).In inflammation severity of biopsies from 89 OLT explants and 2 patients in pre-transplant,the degree of severe inflammation(A3F4,0.0%)was significantly less frequent than in patients with minimal and moderate degree of inflammation(≤A2F4,16.2%)P=0.048,in patients carrying the APOE4 allele when compared to *** addition,a significant difference was also found(≤A2F4,64.4%vs A3F4,0.0%;P=0.043)and(A1F4,57.4%vs A3F4,0.0%;P=0.024)in APOE4 patients when compared to APOE3 *** fibrosis degree of the liver graft in 8 of 91 patients and the lack of the E4 allele was associated with more moderate fibrosis(F2)(P=0.006).CONCLUSION Our results suggest that the E4 allele protects against progression of liver fibrosis and degree of inflammation in HCV-infected patients.

关键词： Apolipoprotein E Polymorphism Liver cirrhosis Hepatitis C virus Hepatocellular carcinoma Liver transplantation