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Search Results: 1 - 10 of 187980 matches for " Marcos Aurélio Vasconcelos de Freitas "
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Recovery Process on Soft-Bottom Macrobenthic Communities after Artificial Disturbance in Tropical Polluted Estuary (Guanabara Bay, Rio de Janeiro, Brazil)  [PDF]
Cecília do Valle Pinto Pereira, Leandro Amaro Pessoa, Marcos Aurélio Vasconcelos de Freitas, Carlos Alejandro Echeverría
Open Journal of Marine Science (OJMS) , 2013, DOI: 10.4236/ojms.2013.34018
Abstract:

The regime of disturbance with natural or anthropogenic origin can lead to the destabilization or even to a mass mortality of benthic communities. Due to the heterogeneity of the disturbance there is a formation of patches in different stages of ecological succession. The aim of this study is to follow and describe the resilience in artificial disturbed sediment in a polluted bay in Rio de Janeiro. The sediment was collected, sterilized and placed inside corers (10 cmdiameter ×15 cmheight) in the same place where it was collected. We allocated the samples in two structures, the difference between them was that one was placed closed to the bottom and the other was placed50 cmheight. We found 2352 organisms distributed in 14 taxons. The class Polychaeta and the order Amphipoda showed the highest density in all the survey and treatments. We identified the factors influencing the scenarium: different mechanisms of dispersal, the position of the structures and life history of each group. Disturbance can be the main cause of the patch’s diversity found in estuaries and coastal areas. Because of this, monitoring of selected areas becomes an important tool to understand the regime of disturbance as a key factor structuring benthic communities in soft sediment, also suggesting a metapopulation dynamics.

Spatial Analysis of Affected Areas by Extreme Hydrological Events in Rio de Janeiro (The Host City for the 2016 Olympic Games)—Brazil  [PDF]
Leandro Andrei Beser de Deus, Camilla Silva Motta Santos, Patricia Gomes da Silveira, Marcos Aurélio Vasconcelos Freitas, Paulo Márcio Leal Menezes
Journal of Geographic Information System (JGIS) , 2013, DOI: 10.4236/jgis.2013.54032
Abstract:

The most frequent types of disasters in Brazil are associated with extreme hydrological events. Adding to this situation, in Brazil, there are the extreme sociospatial discrepancies that are historically constructed. They leave marks in space, making specific areas, for political interest or not, more vulnerable to the different mentioned processes. To this extent, the public management should plan actions and, also, it may act in a more holistic way adding new trends, such as, the use of geotechnologies that are applied to environmental management in the realm of urban planning. From a case study in the city of Rio de Janeiro, this paper aims to contribute and draw attention to such issues. It may reach its target through pointing and spatially analyzing which areas are in the most critical situation related to the occurrence of extreme hydrological events. To achieve this goal, it was proposed a methodology to inventory the occurrence of inundation/flooding for a certain period, in this case 2001-2008. Besides, the methodology could systematize data and integrate them with other important issues for supporting the process of identification and analysis of the most critical areas. Historical aspects of occupation and the most vulnerable socio-environmental aspects were raised, too, in order to validate the highlighted areas. This integration was enabled concerning the support of geoprocessing techniques. The results of this integration subsidized the mapping and spatial analysis of the affected areas in the city and the criticality in relation to the extreme hydrological events. Finally, it was possible to observe that the identification of the most critical affected areas does not mean the exhaustion of the subject. The location of these areas is directly linked to the sample that was used as the basis for analyses. This data set only represents recorded events by the Municipal Civil Defense respecting the studied time frame. However, the results permit to take notes and raise relevant environmental questions about the roots and the occurred impacts that were originated from the extreme hydrological events, which have been observed in recent decades.

Quali-Quantitative Analysis of Brazilian Environmental Licensing of Hydropower Plants  [PDF]
Fabio Giusti Azevedo de Britto, José Paulo Soares de Azevedo, Cynara Alets Sthuasth Souza de Melo Fran?a, Rodrigo Cunha Wanick, Leandro Andrei Beser de Deus, Marcos Aurélio Vasconcelos de Freitas
International Journal of Geosciences (IJG) , 2015, DOI: 10.4236/ijg.2015.67056
Abstract: The use of the extraordinary hydroelectric potential of the Amazon Basin originated an increase in the offer of renewable energy in Brazil, which, in its turn, leads to conflicts and a lack of consensus among different players owing to the potential negative impacts related to the construction and operation of large hydroelectric power plants in relatively well preserved areas. In this context, environmental licensing is one of the national environmental policy’s main instruments for making decisions regarding the use of the hydroelectric potential, especially the rivers of the Amazon Basin. Nevertheless, this significant instrument has its limitations and requires adjustments in order to better aid the decision making process regarding the use of water resources and land with the goal of increasing the offer of electric energy.
Nutritional value of the straw of green maize for bovines Valor nutritivo da palha de milho verde para bovinos
Marcos Augusto de Castro Filho,Marco Aurélio Alves de Freitas Barbosa,Ronaldo Lopes Oliveira,Adriana Regina Bagaldo
Revista Brasileira de Saúde e Produ??o Animal , 2007,
Abstract: The objective was evaluate the use of the straw of green maize, byproduct derived from green maize extraction process, by determining chemical composition; in situ dry matter and neutral detergent fiber; the index of forage value; estimative of dry matter digestibility, total digestible nutrients and net energy for lactation, as well as dry matter intake. Degradability in situ was performed in bovines fistulated in rumen, at incubation time of 96h,72h, 48h, 24h, 12h, 9h, 6h, 3h, and 0h. A completely randomized design was used and effective degradability for DM and NDF at 2, 5 and 8% of passage rate were estimated. The index of forages value, estimative of the dry mater digestibility, total digestible nutrients and the liquid energy for lactation, as well as dry matter intake of this byproduct were reached by means of predicted equations. The results suggested an interesting profile for the use of byproduct of the straw of grain maize for feeding bovines compared to other feedstuffs with good quality. O objetivo foi avaliar a utiliza o da palha de milho verde, co-produto do beneficiamento industrial do milho verde, para a alimenta o de bovinos determinando-se a composi o químico-bromatológica; a degradabilidade in situ da matéria seca e da fibra em detergente neutro; o índice de valor forrageiro; e a estimava da digestibilidade da matéria seca, dos nutrientes digestíveis totais e da energia líquida para lacta o, bem como do consumo de matéria seca desse alimento. Foram realizados ensaio em análises químico-bromatológicas e em degradabilidade in situ da palha de milho verde. A degradabilidade in situ foi realizada em bovinos fistulados no rúmen, utilizou-se um delineamento inteiramente casualizado e estimou-se a degradabilidade efetiva a 2, 5 e 8% de taxa de passagem. O índice de valor forrageiro; e a estimava da digestibilidade da matéria seca, dos nutrientes digestíveis totais e da energia líquida para lacta o, bem como do consumo de matéria seca desse alimento foram obtidas por meio de equa es de predi o. Foram obtidos dados que sugerem perfil interessante para a utiliza o do co-produto PMV na alimenta o de bovinos em compara o a outros alimentos tidos como de boa qualidade, levando-se em considera o suas característas intrínsecas como co-produto e a sua utiliza o para esse fim.
Curva crítica de dilui??o do nitrogênio para a cultura do mel?o
Foga?a, Marco Aurélio de Freitas;Andriolo, Jer?nimo Luiz;Godoi, Rodrigo dos Santos;Barros, Cláudia Alessandra Peixoto de;Janisch, Djeimi Isabel;Vaz, Marcos André Braz;
Ciência Rural , 2008, DOI: 10.1590/S0103-84782008000200008
Abstract: the research was carried out to adjust the nitrogen critical dilution curve for the muskmelon crop, to be used in fertilization practices for this crop. the experiment was conducted in a greenhouse at universidade federal de santa maria, from august to january, 2005. plantlets of the hybrid magellan was grown in polyethylene bags with 4.5dm3 of the commercial substrate plantmax pxt?, in a plant density of 3.3plants m-2, and fertigated with a complete nutrient solution. plants were vertically trained with one stem and no more than two fruits per plant, and the main stem was cut at 2m height. treatments were n concentrations in the nutrient solution of 8, 11, 14, 17, and 20mmol l-1, in a randomized experimental design with four replications. four plants of each treatment were harvested at weekly intervals between 33 and 99 days after planting to determine dry mass (dm) accumulation and n concentration in leaves, stem and fruits. the n dilution in plant dry mass was confirmed in all treatments and data fitted the potential model %n = ams-b described in the literature. the n dilution curve was adjusted, with values of 5.16 and 0.63 for a and b coefficients, respectively. this model could be used to estimate the n quantity absorbed during growth and development of this crop, based on the analysis of this element on leaf tissues.
Síntese sobre ofiolitos: evolu??o dos conceitos
Queiroga, Gláucia Nascimento;Suita, Marcos Tadeu de Freitas;Pedrosa-Soares, Ant?nio Carlos;Martins, Maximiliano de Souza;Pinheiro, Marco Aurélio Piacentini;
Rem: Revista Escola de Minas , 2012, DOI: 10.1590/S0370-44672012000100007
Abstract: ophiolites are fragments of the ancient oceanic lithosphere formed at constructive plate margins or transforming divergent plates. through extensive thrust faults, these bodies or part of them are emplaced into the continental crust, inside rock piles of orogenic belts, in solid state, but these bodies can be relatively warm. the possible environments which produce oceanic lithosphere include meso-oceanic ranges, basins related to juvenile island arcs and retro-arc basins. ophiolites of the phanerozoic age are abundant in orogenic belts around the world whilst precambrian oceanic remnants are less common and are distributed mainly in finland, canada, morocco, saudi arabia, egypt, russia, brazil and china. several registers of precambrian oceanic remnants of different ages were recognized in brazil. most of these bodies are situated in brazilian orogenic belts and they register the consumption of the neoproterozoic oceans. this paper aims to synthetize the main information about ophiolitic sequences, bringing a brief review of concepts and classifications along the 200-year use of this term.
Oxisol subsurface chemical attributes related to sugarcane productivity
Landell, Marcos Guimar?es de Andrade;Prado,lio do;Vasconcelos, Ant?nio Carlos Machado de;Perecin, Dilermando;Rossetto, Raffaella;Bidoia, Márcio Aurélio Pitta;Silva, Marcelo de Almeida;Xavier, Mauro Alexandre;
Scientia Agricola , 2003, DOI: 10.1590/S0103-90162003000400020
Abstract: in spite of the great homogeneity found in the morphological characteristics of oxisols, there is great chemical diversity in subsurface layers of these soils. studies indicate that crop yield presents significant correlation with the chemical attributes of the subsurface, which, are more stable than attributes found in the plough layer, subject to greater alterations as a consequence of agricultural exploration. this work evaluated the effects of subsurface chemical attributes of oxisols of the south central region of brazil, on the yield of sugarcane clones and of variety rb72454, during the first, second and third cropping cycles. productivity data were obtained between 1993 and 1998. soils were characterized in terms of their mechanical analysis and chemical traits at 0.8 to 1.0 m; correlation studies between these attributes and mean daily productivity as well as multiple regression analysis were also carried out; variables were selected based on their r2 values by means of the stepwise procedure. the subsurface chemical traits of the oxisols influenced sugarcane productivity, especially the 3rd harvest; the clone productivity model for the 3rd harvest as a function of base saturation and phosphorus content presented r2 = 0.31, i.e., 31% of the variation in sugarcane yield (t ha-1 day-1) can be explained by these two attributes. for variety rb72454, 47% of that variation is explained by the sum of bases and contents of calcium and organic matter. variations on productivity at 1st and 2nd harvests can be better explained by phwater.
Transplante cardíaco no Instituto Dante Pazzanese de Cardiologia: análise da sobrevida
ASSEF, Marco Aurélio Salles;VALBUENA, Paulo Fernando MF;NEVES Jr., Marcondes Tavares;CORREIA, Edileide Barros;VASCONCELOS, Marcos;MANRIQUE, Ricardo;MAGALH?ES,lio M. de;SOUZA, Luiz Carlos Bento de;CHACCUR, Paulo;DINKHUYSEN, Jarbas J.;
Revista Brasileira de Cirurgia Cardiovascular , 2001, DOI: 10.1590/S0102-76382001000400003
Abstract: from november 30, 1991 to august 31, 2000, 80 cardiac transplants have been analyzed retrospectively at instituto dante pazzanese de cardiologia. seventy percent of the recipient were male, and the recipient average was 44.8 years(range: 7 to 69 years). twelve patients(15%) were considered priority, receiving inotropic drug support at the moment of transplantation. the diagnosis of the recipients included primary dilated cardiomiopathy (37.5%), ischemic cardiomiopathy (33.75%), cardiomiopathy by chagas disease (17.5% ) and others (11.25%). seventy eight transplants were orthotopic, and two heterotopic. surgical technique used was bicaval/bipulmonar (63.75%), atrial (27.5%), bicaval/unipulmonar (6.25%) and heterotopic (2.5%). the 30 day mortality for all patients was 18.75%. the survival after orthotopic transplant in one year was of 72.7%; in five years was 61.5%, and in seven years was of 56.4%. the survival after transplant was related to the following variables: age, cause of death and sex of the donor, and wheter the transplant was or not the patient's first cardiac surgery .
Nitrogênio e potássio via água de irriga??o nas características de produ??o da bananeira 'Grand Naine'
Sousa, Valdemício Ferreira de;Veloso, Marcos Emanuel da Costa;Vasconcelos, Lúcio Flavo Lopes;Ribeiro, Valdenir Queiroz;Souza, Valdomiro Aurélio Barbosa de;d'Albuquerque Junior, Boanerges Siqueira;
Pesquisa Agropecuária Brasileira , 2004, DOI: 10.1590/S0100-204X2004000900005
Abstract: the objective of this work was to evaluate the effect of nitrogen and potassium, applied through irrigation water by microsprinkler, on the production characteristics of banana, cv. grand naine. the experimental design was a randomized block with four replications. the treatments consisted of 30, 180, 300, 420 and 570 kg ha-1 year-1 of n and of 55, 330, 550, 770 and 1,045 kg ha-1 year-1 of k2o and a control treatment (no fertilizers), totalizing 11 treatments, according to the plan puebla iii experimental matrix model. the following characteristics were evaluated: average fruit mass, average bunch mass, and fruit yield, referent to the first and the second production cycles. in the first and second production cycle, average fruit mass, average bunch mass and fruit yield were influenced only by the potassium. higher values of average fruit mass (253.47 g), average bunch mass (28 kg) and fruit yield (55.42 t ha-1), for the first production cycle, were obtained with the application of 938.46, 665.38 and 635.00 kg ha-1 of k2o, respectively. in the second cycle, higher values in relation average fruit mass (174.22 g), average bunch mass (32.04 kg) and yield (60.89 t ha-1) were gathered with the application of 725.50, 907.50 and 933.33 kg ha-1 of k2o, respectively. there was no response of evaluated characteristics to nitrogen.
Organic and inorganic sources of zinc, copper and selenium in diets for dairy cows: intake, blood metabolic profile, milk yield and composition
Cortinhas, Cristina Sim?es;Freitas Júnior, José Esler de;Naves, Julianne de Rezende;Porcionato, Marco Aurélio de Felicio;Silva, Luís Felipe Prada e;Rennó, Francisco Palma;Santos, Marcos Veiga dos;
Revista Brasileira de Zootecnia , 2012, DOI: 10.1590/S1516-35982012000600023
Abstract: the present study was carried out with the objective of evaluating the effects of feeding dairy cows with organic or inorganic sources of zinc (zn), copper (cu) and selenium (se) on blood concentrations of these minerals, blood metabolic profiles, nutrient intake and milk yield and composition. nineteen holstein cows were selected and randomly assigned to two groups for receiving organic (n = 9) or inorganic (n = 10) sources of zn, cu and se from 60 days before the expected date of calving to 80 days of lactation. samples of feed, orts and milk were collected for analysis. body condition score (bcs) was determined and blood samples were collected for analysis of zn, cu and se concentrations, as well as for metabolic profile. supplying organic or inorganic sources of zn, cu, and se did not affect dry matter and nutrient intake, blood metabolic profile, milk yield and composition, plasma concentration of these minerals, and bcs or change the bcs in cows from 60 days before the expected date of calving to 80 days of lactation. an effect of time was observed on all feed intake variables, plasma concentrations of zn and se, milk yield, milk protein content, bcs and change in bcs.
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