Produção Nacional
Revisado por pares
Péricles Pereira Júnior, Pedro Milanez de Rezende, Stephan Carvalho Malfitano, Rafaela Karin Lima, Luíza Vasconselos Tavares Corrêa, Evrerson Reis Carvalho,
A soja [Glycine max (L.) Merrill] é o principal produto agrícola da exportação brasileira, portanto, torna-se importante a realização de estudos que contribuam para a minimização dos efeitos que possam causar a diminuição do rendimento e a depreciação da qualidade dessa oleaginosa, como a ocorrência de pragas e doenças, problemas com a fertilidade do solo e adversidades climáticas, entre outros. Sabe-se que as plantas diferem na sua capacidade de absorver silício (Si), sendo assim diferentemente classificadas. ...
Tópico(s): Aluminum toxicity and tolerance in plants and animals
2010 - UNIVERSIDADE FEDERAL DE LAVRAS | Ciência e Agrotecnologia
Produção Nacional
Revisado por pares
Gleison Souza Diniz Mendonça, Breno Campos Ferreira Guimarães, Péricles Alves, Márcio Pereira, Guido Araújo, Fernando Magno Quintão Pereira,
Directive-based programming models, such as OpenACC and OpenMP, allow developers to convert a sequential program into a parallel one with minimum human intervention. However, inserting pragmas into production code is a difficult and error-prone task, often requiring familiarity with the target program. This difficulty restricts the ability of developers to annotate code that they have not written themselves. This article provides a suite of compiler-related methods to mitigate this problem. Such ...
Tópico(s): Software Engineering Research
2017 - Association for Computing Machinery | ACM Transactions on Architecture and Code Optimization
Produção Nacional
Revisado por pares
Jacqueline Wanessa de Lima Pereira, Péricles de Albuquerque Melo Filho, Manoel Bandeira de Albuquerque, Rejane Jurema Mansur Custódio Nogueira, Roseane Cavalcanti dos Santos,
Cinco genótipos de amendoim de diferentes hábitos de crescimento foram submetidos a estresse hídrico moderado durante 7 dias em casa de vegetação. O plantio foi feito em vasos de 15 litros contendo solo e substrato (Plantmax®), otimizados para a cultura. O delineamento experimental adotado foi inteiramente casualizado, com esquema bi-fatorial 5 × 2 (5 genótipos × 2 tratamentos hídricos), com cinco repetições. As atividades enzimáticas da SOD, CAT, APX e GPX foram analisadas, além do acúmulo de carboidratos, ...
Tópico(s): Soybean genetics and cultivation
2012 - UNIVERSIDADE FEDERAL DO CEARÁ | Ciência Agronômica/Revista ciência agronômica
Produção Nacional
Revisado por pares
Renato M. Cotta, Carolina P. Naveira‐Cotta, Diego C. Knupp, José Luiz Zanon Zotin, Péricles C. Pontes, André Pereira de Almeida,
An unifying overview of the Generalized Integral Transform Technique (GITT) as a computational-analytical approach for solving convection-diffusion problems is presented. This work is aimed at bringing together some of the most recent developments on both accuracy and convergence improvements on this well-established hybrid numerical-analytical methodology for partial differential equations. Special emphasis is given to novel algorithm implementations, all directly connected to enhancing the eigenfunction ...
Tópico(s): Numerical methods in engineering
2017 - Springer Science+Business Media | Heat and Mass Transfer
Produção Nacional
Carolina S.L. Franca, Fábia S. Menezes, L.C.B. Costa, Edenilson dos Santos Niculau, Péricles Barreto Alves, José Eduardo Brasil Pereira Pinto, Rosilene M. Marçal,
Ocimum selloi essential oil (2, 20, and 200 mg/kg; p.o.) reduced, in a dose-dependent way, the abdominal contraction induced by acetic acid (0.6%; i.p.) and the diarrhea episodes induced by castor oil in mice. At the higher dose (200 mg/kg; p.o.), the essential oil significantly reduced intestinal transit (P < 0.05) in the charcoal meal test. The main component detected in O. selloi essential oil was methyl chavicol (98%; GC and GC/MS).These effects seems to support the use of O. selloi against diarrhea, ...
Tópico(s): Psidium guajava Extracts and Applications
2008 - Elsevier BV | Fitoterapia
Produção Nacional
Revisado por pares
Antonio Edílson da Silva Araújo, V. L. D. Baldani, Péricles de Souza Galisa, J. A. Pereira, José Ivo Baldani,
The largest numbers of the Brazilian traditional upland rice varieties are found in the Maranhão state, Northeast region of Brazil. However, no information is available on the diazotrophic bacterial population associated as well as the plant growth promoting potential when these traditional genotypes are inoculated with native strains. Here, we evaluated the response of ten traditional rice varieties to inoculation with ten diazotrophic strains, previously isolated from rice soil of this region ...
Tópico(s): Cassava research and cyanide
2012 - Elsevier BV | Applied Soil Ecology
Produção Nacional
Revisado por pares
Igor Rafael de Assis Costa, Henrique Nazaré Santos, Péricles Alves, Fernando Magno Quintão Pereira,
JavaScript emerges today as one of the most important programming languages for the development of client-side web applications. Therefore, it is essential that browsers be able to execute JavaScript programs efficiently. However, the dynamic nature of this programming language makes it very challenging to achieve this much needed efficiency. In this paper we propose parameter-based value specialization as a way to improve the quality of the code produced by JIT engines. We have empirically observed ...
Tópico(s): Software Testing and Debugging Techniques
2013 - Elsevier BV | Computer Languages Systems & Structures
Produção Nacional
Revisado por pares
P. Colepicolo-Neto, Hosana Maria Debonsi, Gustavo Souza dos Santos, Karen Cristina Rangel, Thaiz Rodrigues Teixeira, Lorena Rigo Gaspar, Péricles Gama Abreu-Filho, Luíz Miguel Pereira, Ana Patrícia Yatsuda, Marília Elias Gallon, Leonardo Gobbo‐Neto, Leandro da Costa Clementino, Márcia A. S. Graminha, Laís Garcia Jordão, Adrian Martin Pohlit,
Abstract Leishmaniasis, malaria, and neosporosis are parasitic diseases that affect humans and animals, causing public health problems and billions in economic losses. Despite the advances in the development of new drugs, the severe side effects of available leishmaniasis treatments, the Plasmodium spp. resistance to antimalarial drugs, and the lack of a specific treatment against neosporosis lead us to the search for new anti-protozoan molecules from underexplored sources such as the Antarctic ...
Tópico(s): Malaria Research and Control
2020 - Georg Thieme Verlag | Planta Medica International Open
Produção Nacional
Revisado por pares
Paulo A Farias-Junior, Marcos C Rios, Tauanny A Moura, Roque Pacheco de Almeida, Péricles Barreto Alves, Arie Fitzgerald Blank, Roberta Pereira Miranda Fernandes, Ricardo Scher,
Leishamaniasis is a disease that affects more than 2 million people worldwide, whose causative agent is Leishmania spp. The current therapy for leishmaniasis is far from satisfactory. All available drugs, including pentavalent antimony, require parenteral administration and are potentially toxic. Moreover, an increase in clinical resistance to these drugs has been reported. In this scenario, plant essential oils used traditionally in folk medicine are emerging as alternative sources for chemotherapeutic ...
Tópico(s): Essential Oils and Antimicrobial Activity
2012 - BioMed Central | Biological Research
Produção Nacional
Revisado por pares
Sandy Sampaio Videira, Michele de Cássia Pereira e Silva, Péricles de Souza Galisa, Armando Cavalcante Franco Dias, Riitta Nissinen, Vera Lúcia Baldani Divan, Jan Dirk van Elsas, José Ivo Baldani, Joana Falcão Salles,
Tópico(s): Anaerobic Digestion and Biogas Production
2013 - Springer Science+Business Media | Plant and Soil
Produção Nacional
Revisado por pares
Ezequias Rodrigues Pestana, Emanuel Péricles Salvador, Guilherme Borges Pereira, Cristiano Teixeira Mostarda, Richard Diego Leite, Cristiane Rocha Silva, Wellington Roberto Gomes de Carvalho,
Tópico(s): Eating Disorders and Behaviors
2017 - Springer Science+Business Media | Sport Sciences for Health
Produção Nacional
Revisado por pares
Péricles Nóbrega Mendes, Sheila Canevese Rahal, Oduvaldo Câmara Marques Pereira-Júnior, Viciany Erique Fabris, S L R Lenharo, J. F. Lima-Neto, Fernanda da Cruz Landim‐Alvarenga,
Abstract Background Barrier materials as cellulose membranes are used for guided tissue repair. However, it is essential that the surrounding tissues accept the device. The present study histologically evaluated tissue reaction to a microbial cellulose membrane after subcutaneous implantation in mice. Furthermore, the interaction between mesenchymal stem cells and the biomaterial was studied in vitro to evaluate its ability to act as cellular scaffold for tissue engineering. Methods Twenty-five ...
Tópico(s): Tissue Engineering and Regenerative Medicine
2009 - BioMed Central | Acta veterinaria Scandinavica
Produção Nacional
Revisado por pares
Simone S. Nascimento, Adriano Antunes de Souza Araújo, Renan Guedes de Brito, Mairim Russo Serafini, Paula dos Passos Menezes, Josimari Melo DeSantana, W. Lucca Júnior, Péricles Barreto Alves, Arie Fitzgerald Blank, Rita Oliveira, Aldeídia Pereira de Oliveira, Ricardo Luiz Cavalcanti de Albuquerque Júnior, Jackson Roberto Guedes da Silva Almeida, Lucindo José Quintans‐Júnior,
O. basilicum leaves produce essential oils (LEO) rich in monoterpenes. The short half-life and water insolubility are limitations for LEO medical uses. β-Cyclodextrin (β-CD) has been employed to improve the pharmacological properties of LEO. We assessed the antihyperalgesic profile of LEO, isolated or complexed in β-CD (LEO/β-CD), on an animal model for fibromyalgia. Behavioral tests: mice were treated every day with either LEO/β-CD (25, 50 or 100 mg/kg, p.o.), LEO (25 mg/kg, p.o.), tramadol (TRM 4 mg/ ...
Tópico(s): Phytochemicals and Medicinal Plants
2014 - Multidisciplinary Digital Publishing Institute | International Journal of Molecular Sciences
Produção Nacional
Revisado por pares
Fabiana Piovesan, Francisco José Veríssimo Veronese, Auri Ferreira Santos, Roberta Pozza, Péricles Serafim Sarturi, Alexandre Pereira Tognon, Valter Duro Garcı́a, Elizete Keitel, David Saitovitch,
FUNDAMENTO: A ocorrência de hiper-homocisteinemia parece ser freqüente após o transplante renal. Nenhum estudo até o momento avaliou o papel da homocisteína (Hcy) associada à dislipidemia no Brasil. OBJETIVO: Determinar a prevalência de hiper-homocisteinemia (Hcy sérica >15 mmol/l) em pacientes estáveis submetidos a transplante renal e avaliar o papel dos lipídios séricos e da função do enxerto nos níveis de Hcy sérica. MÉTODOS: Cento e cinco pacientes estáveis submetidos a transplante renal foram ...
Tópico(s): HIV-related health complications and treatments
2007 - Sociedade Brasileira de Cardiologia (SBC) | Arquivos Brasileiros de Cardiologia
R. R. da Silva, Irai Manuela Santana Santos, George Moreno De Oliveira, Adheilton Rogers Pilé de Carvalho, Péricles Pereira Júnior, Iris Santana Gonçalves,
Tópico(s): Irrigation Practices and Water Management
2015 - | Revista Brasileira de Agricultura Irrigada
Produção Nacional
Revisado por pares
Jéferson Deleon Fávero, Péricles Ewaldo Jader Pereira, Giancarlo Gomes, Luciano Castro de Carvalho,
A cada dia que passa o cenário encontrado nas indústrias se torna mais complexo, nesse contexto existe a necessidade e a busca constante por inovação. O capital intelectual e a capacidade absortiva têm sido observados como um recurso estratégico das organizações devido a capacidade que a empresa possui em criar e aplicar a sua base de conhecimento. Neste contexto, sugere-se que o desempenho inovador (DI) é influenciado pela gestão do capital intelectual (CI) e da capacidade absortiva (ACAP). Baseado ...
Tópico(s): Intellectual Capital and Performance Analysis
2020 - | Revista Gestão Organizacional
Produção Nacional
Revisado por pares
Gabriella B. Souza, Tamiris A. C. Santos, Amanda P. S. Silva, André L. B. S. Barreiros, Victória Brandão Nardelli, Ingrid Borges Siqueira, Silvio Santana Dolabella, Emmanoel Vilaça Costa, Péricles Barreto Alves, Ricardo Scher, Roberta Pereira Miranda Fernandes,
Gabriella B. Souzaa , Tamiris A. C. Santosb , Amanda P. S. Silvac, André L. B. S Barreirosa , Victória Brandão Nardellid, Ingrid B. Siqueirac, Silvio S. Dolabellac , Emmanoel.V. Costad , Péricles B. Alvesa , Ricardo Scherc & Roberta P. M. Fernandesb* a Departamento de Química, Universidade Federal de Sergipe, São Cristóvão, SE, Brasilb Departamento de Fisiologia, Universidade Federal de Sergipe, São Cristóvão, SE, Brasilc Departamento de Morfologia, Universidade Federal de Sergipe, São Cristóvão, SE, Brasild ...
Tópico(s): Research on Leishmaniasis Studies
2022 - Taylor & Francis | Natural Product Research
Produção Nacional
Revisado por pares
Edenilson dos Santos Niculau, Péricles Barreto Alves, Paulo César de Lima Nogueira, Valéria Regina de Souza Moraes, Andréia Pereira Matos, Antônio Bernardo, Ana Carolina Volante, João Batista Fernandes, Maria Fátima das Graças Fernandes da Silva, Arlene G. Corrêa, Arie Fitzgerald Blank, Anderson de C. Silva, Leandro do Prado Ribeiro,
Pelargonium graveolens l'Herit AND Lippia alba (Mill) N. E. Brown AGAINST Spodoptera frugiperda (J.E. Smith).Insecticidal activity of essential oils of Pelargonium graveolens, Lippia alba and compounds geraniol, linalool, 1,8-cineole, limonene, carvone, citral and Azamax ® were evaluated against Spodoptera frugiperda.Topical application assay showed essential oil of P. graveolens has acute toxicity against Spodoptera frugiperda larvae (third instar) with LD 50 1.13 µg/mg per insect and LD 90 2.56 µg/ ...
Tópico(s): Insect Pest Control Strategies
2013 - Brazilian Chemical Society | Química Nova
Produção Nacional
Revisado por pares
Juliana Oliveira de Melo, Tamires A. Bitencourt, Ana Lúcia Fachin, Elizângela Mércia Oliveira Cruz, Hugo César Ramos de Jesus, Péricles Barreto Alves, Maria de Fátima Arrigoni-Blank, Suzelei de Castro França, Renê Oliveira Beleboni, Roberta Pereira Miranda Fernandes, Arie Fitzgerald Blank, Ricardo Scher,
Lippia gracilis, popularly known in Brazil as 'alecrim-de-tabuleiro', is used for many purposes, especially antimicrobial and antiseptic activities. The leaves of three L. gracilis genotypes, including LGRA-106, LGRA-109 and LGRA-110 were collected from the Active Germplasm Bank located in the "Campus Rural da UFS" research farm at the São Cristóvão country, Sergipe State, Brazil. The essential oils were obtained from leaves of L. gracilis plants by hydrodistillation. Chemical analysis of the essential ...
Tópico(s): Plant Pathogens and Fungal Diseases
2013 - Elsevier BV | Acta Tropica
Produção Nacional
Pericles da Silva Pereira Neto, Ernesto Cordeiro Marujo,
RESUMO O objetivo neste trabalho e examinar os efeitos das aliancas entre empresas de transporte aereo de passageiros. Dentre seus beneficios, costumam-se citar: possibilidade de alocar a melhor aeronave para cada segmento com economia de custos, expansao da rede, maior oferta de servicos, maior numero de pares origem-destino para um mesmo total de pax.km voados. Esses beneficios sao claros em uma analise ceteris paribus . Os beneficios estimados nao se materializam como previsto. Isso porque, embora ...
Tópico(s): transportation and logistics systems
2011 - UNIVERSIDADE DE SÃO PAULO | Revista de Administração
Produção Nacional
María José Carvalho de Souza Domingues, Péricles Ewaldo Jader Pereira, Jéferson Deleon Fávero,
El objetivo de este artículo es evaluar los factores que influyen en el uso de teléfonos móviles en el contexto de aprendizaje por parte del profesorado de educación superior. Se realizó una investigación descriptiva con la ayuda de una encuesta cuantitativa. Los datos se obtuvieron por medio de un cuestionario basado en el modelo UTAUT 2, aplicado a docentes de educación superior en la provincia de Santa Catarina, sur de Brasil. El modelo UTAUT 2 está formado por siete variables independientes: ...
Tópico(s): Impact of Technology on Adolescents
2020 - Saint Thomas Aquinas University | Hallazgos
Péricles Ewaldo Jader Pereira, Carlos Marcelo Ardigó, Pablo Flôres Limberger,
Purpose -This study aims to evaluate the relationship between the reputation of the retail brand and customer loyalty in the retail pharmacy sector.Theoretical framework -This article is based on the relationship between customer loyalty and brand reputation.It uses some of the brand reputation variables from the brand equity model (Aaker, 1991) to arrive at an explanatory framework that can differentiate key variables for the most frequented retail pharmacy brands to remain in the market, as well ...
Tópico(s): Organizational Leadership and Management Strategies
2021 - Álvares Penteado School of Commerce Foundation | Review of Business Management
Produção Nacional
Revisado por pares
Yunys Pérez-Betancourt, Péricles Marques Araújo, Bianca de Carvalho Lins Fernandes Távora, Daniele Rodrigues Pereira, Eliana L. Faquim‐Mauro, Ana Maria Carmona‐Ribeiro,
Nanostructures have been of paramount importance for developing immunoadjuvants. They must be cationic and non-cytotoxic, easily assembling with usually oppositely charged antigens such as proteins, haptens or nucleic acids for use in vaccines. We obtained optimal hybrid nanoparticles (NPs) from the biocompatible polymer poly(methyl methacrylate) (PMMA) and the cationic lipid dioctadecyl dimethyl ammonium bromide (DODAB) by emulsion polymerization of methyl methacrylate (MMA) in the presence of DODAB. ...
Tópico(s): Monoclonal and Polyclonal Antibodies Research
2021 - Multidisciplinary Digital Publishing Institute | Pharmaceutics
Produção Nacional
Revisado por pares
Alana Freire de Azevedo, Jorge Luís de Lisboa Dutra, Micheli Luize Barbosa Santos, Darlisson de Alexandria Santos, Péricles Barreto Alves, Tatiana Rodrigues de Moura, Roque Pacheco de Almeida, Marcelo Ferreira Fernandes, Ricardo Scher, Roberta Pereira Miranda Fernandes,
Fatty acids, especially those from phospholipids (PLFA), are essential membrane components that are present in relatively constant proportions in biological membranes under natural conditions. However, under harmful growth conditions, such as diseases, environmental changes, and chemical exposure, the fatty acid proportions might vary. If such changes could be identified and revealed to be specific for adverse situations, they could be used as biomarkers. Such biomarkers could facilitate the identification ...
Tópico(s): Parasites and Host Interactions
2013 - Springer Science+Business Media | Parasitology Research
Produção Nacional
Revisado por pares
Renata Maraschin, Péricles Saremba Vieira, Camila Pereira Leguisamo, Fracieli Dal'Vesco, Juceléia Pertile Santi,
INTRODUÇÃO: A relação entre dor lombar crônica, dor nos membros inferiores e dependência funcional em idosos evidencia-se pelo comportamento da dor durante a execução de atividades da vida diária. Permanecer em pé, puxar ou empurrar objetos grandes e caminhar podem desencadear dor e causar grande sofrimento para os idosos. OBJETIVO: Identificar as causas descritas na literatura relativas à dor lombar crônica e à dor nos membros inferiores em idosas. MÉTODO: Realizou-se busca, nas bases de dados ...
Tópico(s): Youth, Drugs, and Violence
2010 - PONTIFÍCIA UNIVERSIDADE CATÓLICA DO PARANÁ | Fisioterapia em Movimento
Produção Nacional
Revisado por pares
Vanuze Costa de Oliveira, Anacleto Santos, Girlene Souza, Gabriel Lima, Péricles Barreto Alves, Hamilton Pereira Santos,
Oregano's plants were grown in different light environments, obtained with the use of colorful fabrics, in order to evaluate the content and composition of essential oil and anatomical characteristics in leaves of these plants. For this, the plants were grown in pots with capacity for 3 dm³ submitted to the following treatments: cultivation under full sun (absolute witness), shading with blue, red and gray colors. It was adopted the DIC with six repetitions. Anatomical features were evaluated of ...
Tópico(s): Agricultural and Food Sciences
2016 - Sociedade de Ciências Agrárias de Portugal | Revista de Ciências Agrárias
Produção Nacional
Revisado por pares
Ricardo Monteiro Corrêa, José Eduardo Brasil Pereira Pinto, Érika Soares Reis, Leonardo Correia Costa, Péricles Barreto Alves, E.S Niculan, R.S. Brant,
Origanum vulgare L., conhecida como orégano, é considerada planta condimentar largamente usada na culinária. No Brasil poucas são as pesquisas com esta espécie visando maximização das técnicas de cultivo. Objetivou-se avaliar os efeitos de diferentes doses dos adubos orgânicos bovino e aves no crescimento de plantas, teor de clorofila, teor, rendimento e qualidade do óleo essencial de orégano cultivado sob estufa. Foram conduzidos dois ensaios, sendo um com esterco bovino e o outro com esterco de ...
Tópico(s): Agricultural and Food Sciences
2010 - UNIVERSIDADE EST.PAULISTA JÚLIO DE MESQUITA FILHO | Revista Brasileira de Plantas Medicinais
Produção Nacional
Revisado por pares
Andréa Santos da Costa, Maria de Fátima Arrigoni-Blank, Maria Aparecida Azevedo Pereira da Silva, Mércia Freitas Alves, Darlisson de Alexandria Santos, Péricles Barreto Alves, Arie Fitzgerald Blank,
The aim of the present study was to investigate the volatile and sensorial profile of basil (Ocimum basilicum L.) by quantitative descriptive analysis (QDA) of the essential oil of three hybrids ("Cinnamon" × "Maria Bonita," "Sweet Dani" × "Cinnamon," and "Sweet Dani" × "Maria Bonita"). Twelve descriptive terms were developed by a selected panel that also generated the definition of each term and the reference samples. The data were subjected to ANOVA, Tukey's test, and principal component analysis. The hybrid " ...
Tópico(s): Piperaceae Chemical and Biological Studies
2014 - Hindawi Publishing Corporation | The Scientific World JOURNAL
Produção Nacional
Revisado por pares
André Volschan, Denílson Campos de Albuquerque, Bernardo Rangel Tura, Marcos Freitas Knibel, J. Péricles Esteves, Luiz Carlos Bodanese, Francisco José Ferreira da Silveira, JOÃO G. PANTOJA, Paulo Cesar Pereira da Silva e Souza, João Mansur, Evandro Tinoco Mesquita,
FUNDAMENTO: A embolia pulmonar apresenta alta mortalidade em pacientes com hipotensão arterial ou choque circulatório. Entretanto, em pacientes hemodinamicamente estáveis, a associação de algumas variáveis clínicas com a mortalidade ainda não está claramente estabelecida. OBJETIVOS: Derivar um modelo de estratificação do risco de mortalidade intra-hospitalar em pacientes com embolia pulmonar hemodinamicamente estáveis. MÉTODOS: Estudo de coorte multicêntrico prospectivo de 582 pacientes consecutivos ...
Tópico(s): Health Systems, Economic Evaluations, Quality of Life
2009 - Sociedade Brasileira de Cardiologia (SBC) | Arquivos Brasileiros de Cardiologia
Produção Nacional
Revisado por pares
L.C.B. Costa, José Eduardo Brasil Pereira Pinto, Suzan Kelly Vilela Bertolucci, João Cássia do Bomfim Costa, Péricles Barreto Alves, Edenilson dos Santos Niculau,
The efficacy of Ocimum selloi essential oil was evaluated for controlling the growth of mycelia and spores germination Moniliophthora perniciosa. Six compounds (99.89%) of the total oil were identified by GC-MS, of which methyl chavicol, methyl eugenol, β-caryophyllene, germacrene-D, bicyclogermacrene and spathulenol. Essential oil was tested for anti-fungal activity, which was determined by disc diffusion and minimum inhibitory concentration (MIC) determination methods. Application of the oil reduced ...
Tópico(s): Psidium guajava Extracts and Applications
2015 - UNIVERSIDADE FEDERAL DO CEARÁ | Ciência Agronômica/Revista ciência agronômica