997 resultados para adaptação a mudanças climáticas


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As a contemporary tendency, it is been evidenced that the environmental changes theme, already admitted as a concernment to international economical and political reality, is also gaining repercussion on industrial and business sector. Firms are implementing actions on trial to minimize their own greenhouse gases (GHG) emissions impacts. However, the great majority of those actions of Corporative Social-Environmental Responsibility (CSR) are referred only to direct emissions of the main production systems. Direct emissions are those derived of an isolate process, without considering the upstream and downstream processes emissions, which respond for the majority of emissions originated because of respective firm‟s production system existence. Because the greenhouse effect occurs globally and the GHG emissions contribute to the environmental changes independently of their origin, it must be taken into account the whole productive life cycle of products and systems, since the energy invested on resources extraction and necessary materials to the final disposal. To do so, it must be investigated all relevant steps of a product/production system life cycle, tracking all activities which emit greenhouse gases, directly or indirectly. This amount of emissions consists in the firm‟s Carbon Footprint. This research purpose is to defend the Carbon Footprint relevance and its adoption viability to be used as an Environmental Indicator on measurement/assessment of CSR. It has been realized a study case on Petrobras‟s seat unity at Natal-Brazil, assessing part of its Carbon Footprint. It has been used the software GEMIS 4.6 to do the emissions quantifying. The items measured were the direct emissions of the own unity vehicles and indirect emissions of offset paper (A4), energy and disposable plastic cups consumed. To 2009, these emissions were 3.811,94 tCO2eq. We may conclude that Carbon Footprint quantification is indispensable to the knowledge of real emissions caused by a productive process existence, must serving as basis to CSR decisions about the environmental changes reversion challenge

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In multi-robot systems, both control architecture and work strategy represent a challenge for researchers. It is important to have a robust architecture that can be easily adapted to requirement changes. It is also important that work strategy allows robots to complete tasks efficiently, considering that robots interact directly in environments with humans. In this context, this work explores two approaches for robot soccer team coordination for cooperative tasks development. Both approaches are based on a combination of imitation learning and reinforcement learning. Thus, in the first approach was developed a control architecture, a fuzzy inference engine for recognizing situations in robot soccer games, a software for narration of robot soccer games based on the inference engine and the implementation of learning by imitation from observation and analysis of others robotic teams. Moreover, state abstraction was efficiently implemented in reinforcement learning applied to the robot soccer standard problem. Finally, reinforcement learning was implemented in a form where actions are explored only in some states (for example, states where an specialist robot system used them) differently to the traditional form, where actions have to be tested in all states. In the second approach reinforcement learning was implemented with function approximation, for which an algorithm called RBF-Sarsa($lambda$) was created. In both approaches batch reinforcement learning algorithms were implemented and imitation learning was used as a seed for reinforcement learning. Moreover, learning from robotic teams controlled by humans was explored. The proposal in this work had revealed efficient in the robot soccer standard problem and, when implemented in other robotics systems, they will allow that these robotics systems can efficiently and effectively develop assigned tasks. These approaches will give high adaptation capabilities to requirements and environment changes.

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Este artigo pretende estudar a inserção do Brasil no Mecanismo de Desenvolvimento Limpo (MDL) do Protocolo de Quioto, por meio de projetos em energia limpa, enfatizando a cooperação entre países desenvolvidos e em desenvolvimento e visando as ações práticas que esse mecanismo permite desenvolver para se alcançar o desenvolvimento sustentável e para conter o aquecimento global. Para isto, realizou-se extensa revisão bibliográfica dos acordos internacionais referentes às mudanças climáticas e de livros e artigos sobre a inserção brasileira no Protocolo de Quioto e no Mecanismo de Desenvolvimento Limpo. O Protocolo de Quioto é um acordo internacional que prevê a redução das emissões de gases de efeito estufa por intermédio de mecanismos flexibilizadores. O Mecanismo de Desenvolvimento Limpo é o único que permite a participação de países em desenvolvimento, para que eles reduzam emissões por meio de projetos que busquem o desenvolvimento sustentável. Neste contexto, o Brasil surge como um país atrativo para o recebimento destes projetos, por sua vocação para desenvolver fontes alternativas de energia e pela sua liderança no processo negociador do Protocolo. O MDL configura-se, portanto, em uma grande oportunidade para o Brasil, visto que esses projetos representam uma fonte de recursos financeiros para que o país busque o desenvolvimento sustentável, além de incentivarem um maior conhecimento científico e a adoção de novas tecnologias.

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This work deals with the life strategy of an endangered annual fish, Hypsolebias antenori (Cyprinodontiformes: Rivulidae), of the Brazilian semiarid region. The eggs of these fish hatch at the onset of the rainy season, grows rapidly and they reproduce during the rainy season. When the water puddles dry out, the entire population dies. The resistant eggs which are buried in the bottom of the dried pools go through diapause stages, during which time the embryonic development becomes temporarily arrested. With the onset of the next rainy season, the eggs hatch and a new generation is formed. Specimens of H. antenori were captured during 2011 and 2013, in temporary water pools located in the hydrographic basin of river Jaguaribe in Ceará, Brazil. Sex ratio, the length-weight relationship, the growth type, first sexual maturity, anatomy and histology of the digestive tract, development of gonads, reproductive strategy, karyotypic pattern of the species, and the conservation status of H. antenori were investigated. The results of this study are presented in the form of eight articles. The first article is about the fish faunal composition of the hydrographic basins of Rio Grande do Norte, Brazil, wherein the record of H. antenori is included. The second article deals with the sex ratio, secondary sexual characteristics of males, the length-weight relationship and the type of growth. Males show a pattern of intense coloration with well developed fins. The sex ratio showed a significant predominance of females (1M:1.7 F). Males were larger in length and weight. The equation of weight and total length relationship was Wt=0.0271Lt3,8937, showing a positively allometric growth, indicating greater increase in weight than in length. The third article discusses the anatomy and histology of the digestive tract of H. antenori. It is considered as a generalist feeder with characteristics of omnivore, which utilizes different food sources. The fourth article discusses the stages and phases of gonad development and type of spawning of H. antenori. The fifth article is about the r reproductive strategy adopted by H. antenori which helps in successful reproduction over a short period of life. The sixth article deals karyotypic pattern of the species, constituting the first cytogenetic contribution to the genus. The seventh article discusses about the risk of extinction of this species which suffers a series of threats, such as, habitat loss through land use, deforestation, construction of reservoirs, pollution due to domestic and industrial sewage, besides pesticides and agrochemicals. Furthermore, decreasing rainfall and intensification of aridity due to global climate changes, interferes with the reproductive cycle. The eighth article deals with aggressive behavior adopted between males and among females during reproduction. All temporary water pools sampled during this study were in high degree of degradation, mainly due to human action. There is a great need for conservation measures to protect the populations of annual fish, including the creation of protected areas in the semiarid ephemeral aquatic environments of Brazil

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Intensive use of machinery and engines burning fuel dumps into the atmosphere huge amounts of carbon dioxide (CO2), causing the intensification of the greenhouse effect. Climate changes that are occurring in the world are directly related to emissions of greenhouse gases, mainly CO2, gases, mainly due to the excessive use of fossil fuels. The search for new technologies to minimize the environmental impacts of this phenomenon has been investigated. Sequestration of CO2 is one of the alternatives that can help minimize greenhouse gas emissions. The CO2 can be captured by the post-combustion technology, by adsorption using adsorbents selective for this purpose. With this objective, were synthesized by hydrothermal method at 100 °C, the type mesoporous materials MCM - 41 and SBA-15. After the synthesis, the materials were submitted to a calcination step and subsequently functionalized with different amines (APTES, MEA, DEA and PEI) through reflux method. The samples functionalized with amines were tested for adsorption of CO2 in order to evaluate their adsorption capacities as well, were subjected to various analyzes of characterization in order to assess the efficiency of the method used for functionalization with amines. The physic-chemical techniques were used: X- ray diffraction (XRD), nitrogen adsorption and desorption (BET/BJH), scanning electron microscopy (SEM), transmission electron microscopy (TEM), CNH Analysis, Thermogravimetry (TG/DTG) and photoelectron spectroscopy X-ray (XPS). The CO2 adsorption experiments were carried out under the following conditions: 100 mg of adsorbent, at 25 °C under a flow of 100 ml/min of CO2, atmospheric pressure and the adsorption variation in time 10-210 min. The X-ray diffraction with the transmission electron micrographs for the samples synthesized and functionalized, MCM-41 and SBA-15 showed characteristic peaks of hexagonal mesoporous structure formation, showing the structure thereof was obtained. The method used was efficient reflux according to XPS and elemental analysis, which showed the presence of amines in the starting materials. The functionalized SBA -15 samples were those that had potential as best adsorbent for CO2 capture when compared with samples of MCM-41, obtaining the maximum adsorption capacity for SBA-15-P sample

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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This study has as a main objective to make a detailed stratigraphic analysis of the Aptian-Albian interval in the east part of Araripe Basin, NE of Brazil which correspond, litostratigraphically, to Rio Da Batateira, Crato, Ipubi and Romualdo formations. The stratigraphic analysis was based on three different stages, the 1D, 2D and 3D analysis; these ones were adapted to the sequence stratigraphy concepts in order to create a chronostratigraphic framework for the study area within the basin. The database used in the present study contains field and well information, wells that belong to Santana Project, carried out by the Ministério de Minas e Energia- DNPM- CPRM from 1977 to 1978. The analysis 1D, which was done separately for each well and outcrop allowed the recognition of 13 sedimentary facies, mainly divided based on predominant litologies and sedimentary structures. Such facies are lithologically represented by pebble, sandstones, claystones, margas and evaporates; these facies are associated in order to characterize different depositional systems, that integrate from the continental environment (fluvial system and lacustre), paralic system (delta system and lagunar) to the marine environment (shelfenvironment). The first one, the fluvial system was divided into two subtypes: meandering fluvial system, characterized by fill channel and floodplain deposits; the facies of this system are associated vertically according to the textural thinning upward cycles (dirting-up trend pattern in well logs). Lacustrine environment is mainly related with the lithotypes of the Crato Formation, it shows a good distribution within the basin, been composed by green claystone deposits and calcareous laminated. Deltaic System represented by prodelta and delta front deposits which coarsening upward tendency. Lagunar system is characterised by the presence of anhydrite and gypsum deposits besides the black claystone deposits with vegetal fragments which do not contain a fauna typically marine. The marine platform system is composed by successions of black and gray claystone with fossiliferous fauna of Dinoflagellates (Spiniferites Mantell, Subtilisphaera Jain e Subtilisphaera Millipied genre) typical of this kind of depositional system. The sedimentary facies described are vertically arranged in cycles with progradational patterns which form textural coersening upward cycles and retrogradational, represented by textural thinning dowward cycles. Based in these cycles, in their stack pattern and the vertical change between these patterns, the systems tracks and the depositional sequences were recognized. The Low System Track (LST) and High System Track (HST) are composed by cycles with progradational stack pattern, whereas the Trangessive System Track (TST) is composed by retrogradational stack pattern cycles. The 2D stratigraphic analysis was done through the carrying out of two stratigraphic sections. For the selection of the datum the deepest maximum flooding surface was chosen, inside the Sequence 1, the execution of these sections allowed to understand the behaviour of six depositional systems along the study area, which were interpreted as cycles of second order or supercycles (cycles between 3 and 10 Ma), according to the Vail, et al (1977) classification. The Sequence 1, the oldest of the six identified is composed by the low, transgressive and high systems tracks. The first two system tracks are formed exclusively by fluvial deposits of the Rio da Batateira Formation whereas the third one includes deltaic and lacustrine deposits of the Crato Formation. The sequences 2 and 3 are formed by the transgressive systems tracks (lake spreading phase) and the highstand system track (lake backward phase). The TST of these sequences are formed by lacustrine deposits whereas HST contains deltaic deposits, indicating high rates of sedimentary supply at the time of it s deposition. The sequence 4 is composed by LST, TST and HST, The TST4 shows a significant fall of the lake base level, this track was developed in conditions of low relation between the creation rate of space of accommodation and the sedimentary influx. The TST4 marks the third phase of expansion of the lacustrine system in the section after the basin´s rift, the lacustrine system established in the previous track starts a backward phase in conditions that the sedimentary supply rate exceeds the creation rate of space accommodation. The sequence 5 was developed in two different phases, the first one is related with the latest expansion stage of the lake, (TST5), the basal track of this sequence. In this phase the base level of the lake rose considerably. The second phase (related to the TST5) indicates the end of the lacustrine domain in the Araripe Basin and the change to lagunar system ant tidal flat, with great portions in the supratidal. These systems were formed by restricted lagoons, with shallow level of water and with intermittent connections with the sea. This, was the phase when the Araripe Basin recorded the most several arid conditions of the whole interval studied, Aptian Albian, conditions that allow the formation of evaporitic deposits. The sequence 6 began its deposition after a significant fall of the sea (LST6). The sequence 6 is without any doubtlessly, the sequence that has deposits that prove the effective entrance of the sea into the Araripe Basin. The TST6, end of this sequence, represents the moment which the sea reaches its maximum level during the Aptian Albian time. The stratigraphic analysis of the Aptian Albian interval made possible the understanding that the main control in the development of the depositional sequences recognized in the Araripe Basin were the variations of the local base level, which are controlled itself by the climate changes

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Objetivou-se avaliar o desempenho produtivo de bovinos Nelore e suas cruzas com Blonde d'Aquitaine (½ Nelore + ½ Blonde d'Aquitaine) do nascimento ao desmame, mantidos em sistema de pastejo, no Estado de Alagoas. Foram analisadas 1.279 medidas de peso ao nascimento (PN) e peso à desmama ajustado para 210 dias (P210) referentes ao período entre os anos de 2005 e 2010. Utilizou-se o delineamento inteiramente casualizado, adotando-se um nível de significância de 5%. Os pesos médios para PN e P210 foram respectivamente 31,60kg e 158,66kg, para os animais Nelore, e 33,05kg e 167,03kg, para os animais cruzados. Não houve interação (P<0,05) entre grupo genético e sexo do animal, para nenhuma variável analisada. Foram observados efeitos significativos do grupo genético, sexo e época de nascimento (P<0,05) sobre PN. O grupo genético e o sexo foram significativos sobre o P210. O efeito de época de nascimento foi significativo no peso ao nascimento, mas não houve efeito no P210, provavelmente devido à variação climática verificada na região. Animais machos apresentaram pesos superiores (P<0,05) evidenciando o dimorfismo sexual. Os animais cruzados são superiores aos da raça Nelore em todas as características consideradas, proporcionando, inclusive, bezerros mais pesados ao nascimento, sem, no entanto, apresentar partos distócicos. Os animais cruzados também são adequados em relação à grande adaptação às condições climáticas e de manejo às quais foram submetidos, constituindo-se uma excelente opção para cruzamentos na região Nordeste, em condições ambientais semelhantes às deste estudo.

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Devido às mudanças climáticas do planeta, principalmente ao aquecimento global, as formas de utilização dos solos na agricultura têm atraído grande atenção de pesquisadores. Mudanças de manejo podem influenciar a respiração do solo e, por conseguinte, alterar drasticamente o sequestro de C. Os objetivos deste trabalho foram avaliar, em semeadura direta, a influência da calagem nas emissões de CO2 do solo e correlacioná-las aos atributos químicos deste após dois anos da calagem. Utilizou-se o delineamento em blocos casualizados, com seis repetições. Os tratamentos constituíram de quatro doses de calcário e uma testemunha. Decorridos dois anos da calagem, avaliou-se a emissão residual de CO2 do solo, coletaram-se amostras nas camadas de 0-5, 5-10, 10-20 e 20-30 cm de profundidade e determinaram-se os teores de P, Ca2+ e Mg2+ e valores de pH e de saturação por bases. A emissão residual de CO2 do solo, quando a dose recomendada foi aplicada, foi 24,1 % superior, quando comparada à do solo sem aplicação de calcário, e 47,4 % maior, quando se aplicou o dobro da dose recomendada. A calagem melhorou as condições químicas do solo, e a emissão de CO2 aumentou linearmente com o aumento das doses. A emissão de CO2 do solo apresentou correlações positivas com os teores de P, Ca2+ e Mg2+ e com os valores de pH e de saturação por bases e negativas com os teores de H + Al e Al3+. Maiores coeficientes de correlação entre as taxas de emissão de CO2 do solo e os atributos químicos deste ocorreram na camada de 10-20 cm.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)