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Search Results: 1 - 10 of 52418 matches for " Leandro Pereira dos Santos "
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Biomass and Nutrient Accumulation of Cover Crops in the Crop Off-season in Cerrado, in Goiás State, Brazil
Leandro Pereira Pacheco,Marinete Martins de Sousa Medeiros,Rodrigo Fonseca da Silva,Leandro dos Santos Soares
Journal of Agricultural Science , 2012, DOI: 10.5539/jas.v4n9p209
Abstract: The objective of this work was to evaluate the performance of cover crops as for biomass production and nutrient accumulation during the crop off-season in an oxisol in Cerrado, in Goiás State, Brazil. The experiment was performed in Rio Verde, GO, Brazil, from November, 2007 to October, 2008. It was used a randomized block design, with plots divided according to time, with cover crops, and subplots, concerning biomass sampling, with four repetitions. The evaluated cover crops were: Brachiaria ruziziensis, Pennisetum glaucum and B. ruziziensis + Cajanus cajan, and as a reference, fallow treatment with sponteneous species. The biomass samples were collected five times, since the desiccation date of P. glaucum, 60 days after cover crop sowing, which occurred on June, 12th, 2008. The P. glaucum has shown the greatest amount of biomass and nutrient accumulation at 60 days after sowing, while the B. brizantha, B. ruziziensis and B. ruziziensis + C. cajan have shown significant accumulation in the end of the crop off-season.
Agronomic Performance of Cultivars of Upland Rice in the Southern of the Region of Rondônia, Brazil  [PDF]
Edimar Rodrigues Soares, Robertt Fernandes, Laercio da Silva Londero, Diego Lopes dos Santos, Samara Cristina Sampaio Corrêa, Everton Augusto Sampaio Corrêa, Remy Carvalho dos Santos, Ariel Pereira Gomes, Leandro Galon, Fabiana Ferreira Pires, Rosilene da Silva Gon?alves
Agricultural Sciences (AS) , 2014, DOI: 10.4236/as.2014.56053

The upland rice is grown in most Brazilian states. However, in many of them the yield obtained is low. The choice of cultivar more suited to a particular environment can contribute to increased productivity of this crop. This research aimed to evaluate the performance of a hybrid cultivar of upland rice (Ecco) and five conventional cultivars (BRS Monarca, BRS Primavera, AN Cambará, BRS Sertaneja and BRS MG Curinga) in two environments (Vilhena and Cerejeiras). The tests were conducted in the agricultural year 2010/2011. We evaluated the following characteristics: tillering, panicle number per unit area, number of filled grains per panicle sterile, mass of grains per panicle, 1000 grain weight, grain yield (kg·ha-1) and whole grain yield. There was no cultivar x environment interaction for all traits. Greater tillering, higher panicle number per area, higher productivity and yield of whole grains in the municipality of Cerejeiras were observed, while the highest number of sterile grains per panicle was obtained in Vilhena. The hybrid Ecco highlighted in relation to all other cultivars is in relation to tillering, panicle number per area and grain yield. The municipality of Cerejeiras is the most suitable for the cultivation of upland rice.

Ant Colony Optimisation for Backward Production Scheduling
Leandro Pereira dos Santos,Guilherme Ernani Vieira,Higor Vinicius dos R. Leite,Maria Teresinha Arns Steiner
Advances in Artificial Intelligence , 2012, DOI: 10.1155/2012/312132
Abstract: The main objective of a production scheduling system is to assign tasks (orders or jobs) to resources and sequence them as efficiently and economically (optimised) as possible. Achieving this goal is a difficult task in complex environment where capacity is usually limited. In these scenarios, finding an optimal solution—if possible—demands a large amount of computer time. For this reason, in many cases, a good solution that is quickly found is preferred. In such situations, the use of metaheuristics is an appropriate strategy. In these last two decades, some out-of-the-shelf systems have been developed using such techniques. This paper presents and analyses the development of a shop-floor scheduling system that uses ant colony optimisation (ACO) in a backward scheduling problem in a manufacturing scenario with single-stage processing, parallel resources, and flexible routings. This scenario was found in a large food industry where the corresponding author worked as consultant for more than a year. This work demonstrates the applicability of this artificial intelligence technique. In fact, ACO proved to be as efficient as branch-and-bound, however, executing much faster. 1. Production Scheduling Still a Differential for Competitiveness The globalised world economic scenario makes entrepreneurial competitiveness unavoidable and being competitive has become an indispensable prerequisite to organisations that strive for success. Within this context, manufacturing activities become especially important for they decisively influence performance, directly affecting (and being affected by) forecast, planning, and scheduling decisions. Shop-floor production scheduling, which within the hierarchical production planning covers disaggregate and detailed decisions in short time frame, consists in allocating activities (production orders or jobs) to resources, by obeying sequencing and setup restrictions, with focus on getting the best possible results from limited available resources, and, at the same time, aiming at reducing production costs and meeting service levels as fast and efficiently as possible. To make all this happen in cases where production and financial resources are limited and restrictions are many, adequate algorithms techniques and intelligence are necessary. Almost four decades ago, Garey et al. [1] classified production scheduling problems as being NP-hard, which in practical ways means that it is very difficult for one to obtain an optimal solution through exact algorithms and also demand unacceptable execution (computer or effort) time. The
Restri??o alimentar para suínos machos castrados e imunocastrados em termina??o
Santos, Alexandre Pereira dos;Kiefer, Charles;Martins, Leandro Pereira;Fantini, Caiki Calepso;
Ciência Rural , 2012, DOI: 10.1590/S0103-84782012000100024
Abstract: the objective of this study was to evaluate the performance and carcass quantitative characteristics of barrows and immunocastrated swine fed ad libitum or under quantitative feeding restriction. two hundred and forty animals were used, with initial weight of 91.49±3.26kg, distributed in a randomized blocks design, in a factorial scheme 2x2 (two management and two food categories), with four replicates of 15 pigs each. pigs submitted to dietary restriction had lower consumption (p<0.05) than those fed ad libitum. feed intake did not differ (p>0.05) between castrated and immunocastrated. pigs fed ad libitum had higher (p<0.05) weight gain over those submitted to restriction. the immunocastrated showed higher weight gain (p<0.05) than castrated. there was an interaction (p<0.05) between management and categories for feed, in which the restriction improved castrated pigs. immunocastrated had better (p <0.05) feed conversion compared to castrated, regardless of feed management. there was no interaction (p>0.05) among the factors on carcass traits. the restriction did not affect (p>0.05) carcass traits. immunocastrated pigs had lower (p<0.05) back fat thickness and higher percentage of lean meat. dietary restriction improves feed conversion of castrated pigs. the dietary restriction affects weight gain and does not affect carcass characteristics of barrows and immunocastrated. immunocastrated pigs have higher performance, lower back fat thickness and a higher percentage of lean meat compared to the castrated.
Fulereno[C60]: química e aplica??es
Santos, Leandro José dos;Rocha, Guilherme Pereira;Alves, Rosemeire Brondi;Freitas, Rossimiriam Pereira de;
Química Nova , 2010, DOI: 10.1590/S0100-40422010000300036
Abstract: fullerene chemistry has become a very active research field in the two last decades, largely because of the exceptional properties of the c60 molecule and the variety of fullerene derivatives that appear to be possible. in this review, a general analysis of fullerene c60 reactivity is performed. the principal methods for the covalent modification of this fascinating carbon cage are presented. the prospects of using fullerene derivatives as medicinal drugs and photoactive materials in light converting devices are demonstrated.
Avalia??o da dor no recém-nascido prematuro em Unidade de Terapia Intensiva
Santos, Luciano Marques;Pereira, Monick Piton;Santos, Leandro Feliciano Nery dos;Santana, Rosana Castelo Branco de;
Revista Brasileira de Enfermagem , 2012, DOI: 10.1590/S0034-71672012000100004
Abstract: this study aimed to analyze the process of pain identification in premature by the professional staff of the neonatal intensive care unit of a public hospital in the interior of bahia, brazil. this is a quantitative descriptive exploratory study that was made through a form applied to twenty-four health professional of a neonatal intensive care unit. the data were analyzed in the statistical package for social sciences. the results showed 100% of professionals believed that newborns feel pain, 83.3% knew the pain as the fifth vital sign to be evaluated; 54,8% did not know the pain assessment scales; 70.8% did not use scales and highlighted behavioral and physiological signs of the newborn as signs suggestive of pain. thus, it is important that professionals understand the pain as a complex phenomenon that demands early intervention, ensuring the excellence of care.
A família Ochnaceae DC. no estado do Paraná, Brasil
Salvador, Gisele Silvestre;Cervi, Armando Carlos;Brotto, Marcelo Leandro;Santos, élide Pereira dos;
Acta Botanica Brasilica , 2010, DOI: 10.1590/S0102-33062010000200013
Abstract: this work is a survey of the species of ochnaceae occurring in paraná state. two genera were recorded: ouratea aubl. with six species, o. claudei g.s. salvador, e.p. santos & cervi, o. parviflora (dc.) baill., o. salicifolia (a.st.-hil. & tul.) engl., o. sellowii (planch.) engl., o. spectabilis engl., o. vaccinioides (a.st.-hil. & tul.) engl. and sauvagesia l. with four species, s. erecta l., s. racemosa a.st.-hil., s. capillaris (a.st.-hil.) sastre and s. vellozii (a.st.-hil.) sastre. identification key, descriptions, illustrations, comments and geographic distribution are provided for each species.
Modelagem preditiva de linha de costa utilizando redes neurais artificiais
Gon?alves, Rodrigo Mikosz;Coelho, Leandro dos Santos;Krueger, Claudia Pereira;Heck, Bernhard;
Boletim de Ciências Geodésicas , 2010, DOI: 10.1590/S1982-21702010000300004
Abstract: the study of models using geodetic temporal data which can possibly predict the shoreline position is an important task and can significantly contribute to coastal management. the studied area is located at municipality of matinhos in the paraná state, brazil. the temporal shoreline used to test the prediction model is respectively from analog photogrammetric data, related to the years 1954, 1963, 1980, 1991 and 1997, and gps (global position system) geodetic surveys for 2001, 2002, 2005 and 2008 (as control). two different tests with artificial neural network were organized setting the parameters like: architecture, number of neuron in hidden layers and the training algorithms. comparing the residuals between the prediction to the shoreline of control, the best statistical results show the mape (mean absolute percentage error) is 0,28% using the elman partially recurrent network with quasi-newton training function and 0,46% using the neural network multilayer perceptron with bayesian regulation training function.
Desempenho agron?mico de trigo cultivado para gr?os e duplo propósito em sistemas de integra??o lavoura-pecuária
Santos, Henrique Pereira dos;Fontaneli, Renato Serena;Caier?o, Eduardo;Spera, Silvio Tulio;Vargas, Leandro;
Pesquisa Agropecuária Brasileira , 2011, DOI: 10.1590/S0100-204X2011001000013
Abstract: the objective of this work was to assess yield and yield components of wheat cultivated for grain production and for dual-purpose under no-tillage crop-livestock integration systems (clis). grain yield of the two wheat types and yield components for the grain type were evaluated in the 2003 to 2008 growing seasons, in a rhodic hapludox, in coxilha, rs, brazil, in the following systems: 1, wheat/soybean and common vetch/corn; 2, wheat/soybean and black oat pasture/corn; 3, wheat/soybean and black oat pasture/soybean; 4, wheat/soybean and field pea/corn; 5, wheat/soybean, dual-purpose triticale/soybean, and common vetch/soybean; and 6, wheat/soybean, dual-purpose white oat/soybean, and dual-purpose wheat/soybean. a randomized complete block design, with four replicates, was used. there were no differences between clis in yield components (number of spikes, number of grains per spike, and grain mass) of wheat for grain production in differentes clis. the systems 2, 3, 4, and 5 showed higher yield of the grain-type wheat in comparison to 6. there are no significant differences in grain yield, hectoliter weight, and weight of 1,000 kernels between wheat cultivated for grain production and for dual-purpose.
Acúmulo de biomassa em variedades de cana-de-a úcar inoculadas com diferentes estirpes de bactérias diazotróficas Biomass accumulation in sugarcane varieties inoculated with different strains of diazotrophs
Willian Pereira,José Marcos Leite,Guilherme de Souza Hipólito,Carlos Leandro Rodrigues dos Santos
Revista Ciência Agron?mica , 2013,
Abstract: O objetivo do estudo foi avaliar a contribui o da inocula o com bactérias diazotróficas, aplicadas individualmente e em mistura, em variedades comerciais de cana-de-a úcar. O experimento f oi conduzido no Campo Experimental da Embrapa Agrobiologia, em Seropédica-RJ, Brasil. O delineamento experimental foi em blocos casualizados, com parcelas subdivididas e com seis repeti es. Foram utilizadas seis variedades de cana-de-a úcar e seis tratamentos: controle absoluto, controle nitrogenado, inocula o individual das estipes: BR 11512, BR 11724 e BR 11411; além de inocula o com um coquetel composto por cinco estirpes de bactérias diazotróficas. Foi observada diferen a entre variedades, entre tratamentos e uma intera o entre tratamentos e variedades. Para todos os parametros avaliados n o foi observado resposta nas variedades de cana-de-a úcar RB855536 e RB92606. Na variedade RB918639, houve apenas diferen a no acúmulo de biomassa verde. N o foi observada nenhuma diferen a entre tratamentos no acúmulo de nitrogênio total do ponteiro. A variedade mais responsiva à inocula o foi a RB867515, diferenciando no acúmulo de biomassa seca e fresca. Este estudo mostrou que a inocula o promove o acúmulo de biomassa, sendo a contribui o diferente entre variedades e estirpes de bactérias, sugerindo uma intera o entre os fatores estudados. A variedade RB867515 é promissora para os estudos de inocula o com bactérias diazotróficas. The objective of this study was to evaluate the contribution of inoculation with diazotrophs, applied both individually and in combination, in commercial varieties of sugarcane. The experiment was carried out at the experimental grounds of Embrapa Agrobiologia, in Seropédica, Rio de Janeiro, Brazil. The experimental design was of randomised blocks, with sub-divided plots and six replications. Six varieties of sugarcane with six treatments were used: control, control with nitrogen, inoculation of the individual strains: BR 11512, BR 11724 and BR 11411, in addition to inoculation with a cocktail consisting of five strains of diazotrophs. Differences were observed between varieties and between treatments, and an interaction observed between the treatments and varieties. For all the parameters evaluated, no response was observed in the sugarcane varieties RB855536 and RB92606. In the variety RB918639, the only difference was in the accumulation of green biomass. No difference was observed between the treatments for total nitrogen accumulation. The most responsive variety to inoculation was RB867515, differing in the accumulation of fresh and
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