bluuebunny/crossref_metadata_2025 huggingface dataset:
Spared and Impaired Spoken Discourse Processing in Schizophrenia: Effects of Local and Global Language Context
Authors: Swaab Tamara Y. , Boudewyn Megan A. , Long Debra L. , Luck Steve J. , Kring Ann M. , Ragland J. Daniel , Ranganath Charan , Lesh Tyler , Niendam Tara , Solomon Marjorie , Mangun George R. , Carter Cameron S.
Published: September 2013

Individuals with schizophrenia are impaired in a broad range of cognitive functions, including impairments in the controlled maintenance of context-relevant information. In this study, we used ERPs in human subjects to examine whether impairments in the controlled maintenance of spoken discourse context in schizophrenia lead to overreliance on local associations among the meanings of individual words. Healthy controls (n= 22) and patients (n= 22) listened to short stories in which we manipulated global discourse congruence and local priming. The target word in the last sentence of each story was globally congruent or incongruent and locally associated or unassociated. ERP local association effects did not significantly differ between control participants and schizophrenia patients. However, in contrast to controls, patients only showed effects of discourse congruence when targets were primed by a word in the local context. When patients had to use discourse context in the absence of local priming, they showed impaired brain responses to the target. Our findings indicate that schizophrenia patients are impaired during discourse comprehension when demands on controlled maintenance of context are high. We further found that ERP measures of increased reliance on local priming predicted reduced social functioning, suggesting that alterations in the neural mechanisms underlying discourse comprehension have functional consequences in the illness.
Right Supramarginal Gyrus Is Crucial to Overcome Emotional Egocentricity Bias in Social Judgments
Authors: Silani Giorgia , Lamm Claus , Ruff Christian C. , Singer Tania
Published: September 2013

Humans tend to use the self as a reference point to perceive the world and gain information about other people's mental states. However, applying such a self-referential projection mechanism in situations where it is inappropriate can result in egocentrically biased judgments. To assess egocentricity bias in the emotional domain (EEB), we developed a novel visuo-tactile paradigm assessing the degree to which empathic judgments are biased by one's own emotions if they are incongruent to those of the person we empathize with. A first behavioral experiment confirmed the existence of such EEB, and two independent fMRI experiments revealed that overcoming biased empathic judgments is associated with increased activation in the right supramarginal gyrus (rSMG), in a location distinct from activations in right temporoparietal junction reported in previous social cognition studies. Using temporary disruption of rSMG with repetitive transcranial magnetic stimulation resulted in a substantial increase of EEB, and so did reducing visuo-tactile stimulation time as shown in an additional behavioral experiment. Our findings provide converging evidence from multiple methods and experiments that rSMG is crucial for overcoming emotional egocentricity. Effective connectivity analyses suggest that this may be achieved by early perceptual regulation processes disambiguating proprioceptive first-person information (touch) from exteroceptive third-person information (vision) during incongruency between self- and other-related affective states. Our study extends previous models of social cognition. It shows that although shared neural networks may underlie emotional understanding in some situations, an additional mechanism subserved by rSMG is needed to avoid biased social judgments in other situations.
Cannabinoid Transmission in the Prelimbic Cortex Bidirectionally Controls Opiate Reward and Aversion Signaling through Dissociable Kappa Versus μ-Opiate Receptor Dependent Mechanisms
Authors: Ahmad Tasha , Lauzon Nicole M. , de Jaeger Xavier , Laviolette Steven R.
Published: September 2013

Cannabinoid, dopamine (DA), and opiate receptor pathways play integrative roles in emotional learning, associative memory, and sensory perception. Modulation of cannabinoid CB1 receptor transmission within the medial prefrontal cortex (mPFC) regulates the emotional valence of both rewarding and aversive experiences. Furthermore, CB1 receptor substrates functionally interact with opiate-related motivational processing circuits, particularly in the context of reward-related learning and memory. Considerable evidence demonstrates functional interactions between CB1 and DA signaling pathways during the processing of motivationally salient information. However, the role of mPFC CB1 receptor transmission in the modulation of behavioral opiate-reward processing is not currently known. Using an unbiased conditioned place preference paradigm with rats, we examined the role of intra-mPFC CB1 transmission during opiate reward learning. We report that activation or inhibition of CB1 transmission within the prelimbic cortical (PLC) division of the mPFC bidirectionally regulates the motivational valence of opiates; whereas CB1 activation switched morphine reward signaling into an aversive stimulus, blockade of CB1 transmission potentiated the rewarding properties of normally sub-reward threshold conditioning doses of morphine. Both of these effects were dependent upon DA transmission as systemic blockade of DAergic transmission prevented CB1-dependent modulation of morphine reward and aversion behaviors. We further report that CB1-mediated intra-PLC opiate motivational signaling is mediated through a μ-opiate receptor-dependent reward pathway, or a κ-opiate receptor-dependent aversion pathway, directly within the ventral tegmental area. Our results provide evidence for a novel CB1-mediated motivational valence switching mechanism within the PLC, controlling dissociable subcortical reward and aversion pathways.
When the Sense of Smell Meets Emotion: Anxiety-State-Dependent Olfactory Processing and Neural Circuitry Adaptation
Authors: Krusemark Elizabeth A. , Novak Lucas R. , Gitelman Darren R. , Li Wen
Published: September 2013

Phylogenetically the most ancient sense, olfaction is characterized by a unique intimacy with the emotion system. However, mechanisms underlying olfaction–emotion interaction remain unclear, especially in an ever-changing environment and dynamic internal milieu. Perturbing the internal state with anxiety induction in human subjects, we interrogated emotion-state-dependent olfactory processing in a functional magnetic resonance imaging (fMRI) study. Following anxiety induction, initially neutral odors become unpleasant and take longer to detect, accompanied by augmented response to these odors in the olfactory (anterior piriform and orbitofrontal) cortices and emotion-relevant pregenual anterior cingulate cortex. In parallel, the olfactory sensory relay adapts with increased anxiety, incorporating amygdala as an integral step via strengthened (afferent or efferent) connections between amygdala and all levels of the olfactory cortical hierarchy. This anxiety-state-dependent neural circuitry thus enables cumulative infusion of limbic affective information throughout the olfactory sensory progression, thereby driving affectively charged olfactory perception. These findings could constitute an olfactory etiology model of emotional disorders, as exaggerated emotion–olfaction interaction in negative mood states turns innocuous odors aversive, fueling anxiety and depression with rising ambient sensory stress.
Partição de substâncias húmicas em solos brasileiros
Authors: Santos Lauana Lopes dos , Lacerda Julian Junio Jesus , Zinn Yuri Lopes
Published: September 2013

As substâncias húmicas (SH) representam o principal reservatório de carbono orgânico total do solo (COT) e sua partição entre diferentes frações de solubilidade em meio alcalino ou ácido pode guardar relação com o tipo de solo e manejo adotado. O objetivo deste trabalho foi comparar a partição das SHs, de acordo com profundidade, tipo de solo, bioma e uso do solo no Brasil. Revisou-se a literatura, incluindo teses, dissertações, artigos e resumos em anais de eventos, em busca de dados sobre o teor de COT, sua porcentagem como ácidos húmicos (AH), ácidos fúlvicos (AF) e humina (HU) e a razão AH/AF. Os dados foram estratificados por intervalos comparáveis de profundidades (0-5, 5-10, 0-20, 20-50, 50-100 e >100 cm), biomas (Mata Atlântica, Cerrado, Amazônia, Pampa e Caatinga), ordem de solo (Argissolo, Latossolo, Cambissolo, Planossolo, Neossolo, Gleissolo e Organossolo) e principais usos do solo (florestas nativas, pastagem natural, pastagem plantada, eucalipto, culturas perenes e anuais). Os dados foram analisados por estatística descritiva, correlações de Spearman e análise de componentes principais (ACP). Nos Argissolos, Latossolos e Organossolos, a fração HU contribuiu com metade do COT, tendendo a diminuir em profundidade. Para Latossolos e Organossolos, a fração AF tendeu a aumentar em profundidade. Em Neossolos, a fração AH aumentou em profundidade, embora tenha diminuído em Gleissolos e Planossolos. A razão AH/AF geralmente diminui em profundidade. Pela ACP, não foi possível identificar um padrão de agrupamento das amostras em razão do tipo de bioma e uso do solo, sugerindo que a partição das SHs tem baixo potencial como indicador de efeitos do manejo ou condições ambientais, embora seja útil para discriminar processos de humificação em algumas ordens de solo.
Loss of ammonia from nitrogen fertilizers applied to maize and soybean straw
Authors: Faria Letícia de Abreu , Nascimento Carlos Antonio Costa do , Vitti Godofredo Cesar , Luz Pedro Henrique de Cerqueira , Guedes Elaine Maria Silva
Published: September 2013

In Brazilian agriculture, urea is the most commonly used nitrogen (N) source, in spite of having the disadvantage of losing considerable amounts of N by ammonia-N volatilization. The objectives of this study were to evaluate: N lossby ammonia volatilization from: [urea coated with copper sulfate and boric acid], [urea coated with zeolite], [urea+ammonium sulfate], [urea coated with copper sulfate and boric acid+ammonium sulfate], [common urea] and [ammonium nitrate]; and the effect of these N source son the maize yield in terms of amount and quality. The treatments were applied to the surface of a soil under no-tillage maize, in two growing seasons. The first season (2009/2010) was after a maize crop (maize straw left on the soil surface) and the second cycle (2012/2011) after a soybean crop. Due to the weather conditions during the experiments, the volatilization of ammonia-N was highest in the first four days after application of the N sources. Of all urea sources, under volatilization-favorable conditions, the loss of ammonia from urea coated with copper sulfate and boric acid was lowest, while under high rainfall, the losses from the different urea sources was similar, i.e., an adequate rainfall was favorablet o reduce volatilization. The ammonia volatilization losses were greatest in the first four days after application. Maize grain yield differed due to N application and in the treatments, but this was only observed with cultivation of maize crop residues in 2009/2010. The combination of ammonium+urea coated with copper sulfate and boric acid optimized grain yield compared to the other urea treatments. The crude protein concentration in maize was not influenced by the technologies of urea coating.
Objetos de ensino: a renovação pedagógica e material da escola primária no Brasil, no século XX
Authors: Souza Rosa Fátima de
Published: September 2013

O objetivo deste texto é analisar o papel dos objetos de ensino nas proposições de renovação da escola primária durante o século XX assinalando as mudanças na composição material das escolas tendo em vista os objetos que foram introduzidos e ressaltados como relevantes para a modernização da educação e aqueles que permaneceram ou foram redefinidos em termos de finalidades e usos. Pretende-se, dessa forma, examinar três momentos significativos de implantação de inovações na escola elementar: a modernização pelo método intuitivo na virada do século XIX para o século XX, as proposições da Escola Nova nas décadas de 1930 a 1950 e a renovação representada pela Tecnologia Educacional nas décadas de 1960 e 1970.
Identificando o potencial de inovação das organizações por meio da análise do portfólio de projetos de Tecnologia da Informação
Authors: Jaeger Neto José Ignácio , Luciano Edimara Mezzomo , Testa Mauricio Gregianin
Published: September 2013

A gestão do portfólio de projetos contribui para o desenvolvimento das estratégias e objetivos da organização e pode expressar o atual esforço de inovação em uma empresa. A pesquisa tem como tema o potencial de inovação do portfólio de projetos de Tecnologia da Informação. O objetivo é analisar o potencial de inovação do portfólio de projetos de TI, avaliando as características de inovação das ações empreendidas, considerando-se a abrangência da novidade das inovações para a própria empresa. A pesquisa utiliza uma abordagem exploratória por meio de estudo de casos múltiplos em três organizações de grande porte. Os dados analisados provêm dos projetos que fazem parte do portfólio de TI das organizações. A análise dos dados mostra que os critérios utilizados no artigo permitem identificar o potencial de inovação das organizações expresso por meio do portfólio de projetos, na medida em que as inovações são desenvolvidas por meio de projetos.
Influência das variáveis de processo na obtenção de argilas organofílicas
Authors: Ferreira H. S. , Campos L. F. A. , Menezes R. R. , Cartaxo J. M. , Santana L. N. L. , Neves G. A. , Ferreira H. C.
Published: September 2013

As argilas bentoníticas, usadas como agente viscosificante e nanocompósitos, não podem ser usadas sem um prévio tratamento orgânico para que suas superfícies se tornem hidrofóbicas e possam ser dispersas em meios orgânicos. Estas argilas depois de tratadas são chamadas de argilas organofílicas, e são geralmente obtidas através da adição, em meio aquoso, de um agente organofilizante, geralmente um tensoativo, iônico, anfótero ou não iônico. O processo de organofilização, composto de várias etapas, nem sempre garante a obtenção de argilas organofílicas de boa qualidade, sendo importante destacar as variáveis de processo bem como a escolha das matérias-primas a serem utilizadas. Propõe-se então um estudo detalhado das variáveis envolvidas no processo de dispersão das argilas bentoníticas, e também no processo de organofilização procurando relacionar as viscosidades aparente e plástica das dispersões argilosas com a eficiência do processo de organofilização. O processo de organofilização será controlado pelos resultados de difração de raios X e termogravimetria. As variáveis de processo tanto envolvidas na dispersão das argilas quanto na organofilização, do ponto de vista da caracterização, não têm grande influência na incorporação do tensoativo às argilas bentoníticas, sendo influentes o tipo de argila e tensoativo e a presença de sódio como agente defloculante, o que é muito importante de vista industrial pela melhor operacionalidade das condições de processamento.
Produção e teor de amido da batata-doce em cultivo sob adubação com matéria orgânica
Authors: Oliveira Ademar P. de , Gondim Petronio C. , Silva Ovídio P. R. da , Oliveira Arnaldo N. P. de , Gondim Saulo C. , Silva Juliete A.
Published: September 2013

Este trabalho foi realizado na Universidade Federal da Paraíba, Areia, PB, no período de abril a agosto de 2009, com o objetivo de avaliar o comportamento da batata-doce adubada organicamente, em delineamento experimental de blocos casualizados em esquema fatorial 3 x 6, com três fontes de matéria orgânica (esterco bovino, caprino e galinha) seis doses; estercos bovino e caprino (0, 10, 20, 30, 40 e 50 t ha-1) e o esterco de galinha (0, 5, 10, 15, 20 e 25 t ha-1), com três repetições. A fonte de matéria orgânica esterco de caprino e de galinha proporcionou pesos médios de raízes de batata-doce de 264,9 e 197,6 g, respectivamente, nas doses de 39,8 e 12,9 t ha-1. O esterco bovino apresentou massa média de 202,2 g. A produtividade total média em função das doses de esterco bovino foi de 13,3 t ha-1. A máxima produtividade comercial de raízes na batata-doce de 16,7 t ha-1 foi obtida na dose estimada de 29,0 t ha-1 de esterco caprino. Dentre as matérias orgânicas avaliadas o esterco caprino foi o que apresentou melhor resposta para a produtividade comercial de raízes. O teor de amido sofreu influência significativa das fontes de matéria orgânica.
Análise econômica e viabilidade energética da cultura do feijoeiro comum sob irrigação
Authors: Gomes Eder P. , Jordan Rodrigo A. , Motomiya Anamari V. de A. , Padua Juliana B. , Biscaro Guilherme A. , Geisenhoff Luciano O.
Published: September 2013

Este trabalho foi realizado com o objetivo de avaliar a viabilidade econômica e energética da cultura do feijoeiro comum de terceira safra com lâminas de irrigação na região Noroeste do Paraná. O experimento foi implantado com seis lâminas de irrigação e quatro repetições, em delineamento de blocos ao acaso. A cultura do feijoeiro não foi viável economicamente sem irrigação. Os lucros cresceram com o aumento das lâminas de irrigação atingindo um lucro operacional total de R$1.427,24 ha-1 na lâmina de 333 mm. O preço de equilíbrio sem irrigação foi de R$ 134,06 e R$ 152,65 a saca, em curto e longo prazos, respectivamente. A irrigação favoreceu o balanço energético (energia extraída/energia utilizada) de maneira linear atingindo 1,63 na aplicação da maior lâmina (333 mm).
Simulação da distribuição de água em diferentes condições de vento e espaçamentos entre aspersores
Authors: Faria Lessandro C. , Prado Giuliani do , Colombo Alberto , Oliveira Henrique F. E. de , Beskow Samuel
Published: September 2013

Existem inúmeros fatores que afetam a uniformidade de distribuição de água pelos aspersores como, por exemplo, o tipo de aspersor e suas condições operacionais, o espaçamento e sua disposição no campo e a velocidade e direção do vento. Se os aspersores forem selecionados e utilizados adequadamente considerando-se os fatores supracitados, eles podem proporcionar maiores uniformidades de distribuição de água e menores custos do sistema de irrigação. Como a avaliação de todos esses fatores é uma tarefa complexa e morosa, a simulação computacional tem sido uma ferramenta útil no dimensionamento de sistemas de irrigação. Neste estudo objetivou-se determinar, com auxílio de simulação computacional, a uniformidade de distribuição de água do canhão hidráulico Plona-RL250, operando em diferentes condições de vento e espaçamentos e disposições de aspersores. Observou-se que a direção do vento exerceu pouca influência sobre os valores de CUC. Nenhuma vantagem foi encontrada para disposição triangular em comparação com a disposição retangular de aspersores, exceto quando foi usado um espaçamento menor que 40% do diâmetro molhado pelo canhão hidráulico, ao longo da linha principal.
Teores de macronutrientes em folhas de goiabeira fertirrigada com nitrogênio
Authors: Dantas Neto José , Maciel José L. , Alves Aaron de S. , Azevedo Carlos A. V. de , Fernandes Pedro D. , Lima Vera L. A. de
Published: September 2013

O objetivo deste estudo foi diagnosticar os teores de macronutrientes nitrogênio, fósforo, potássio, cálcio e magnésio nas folhas de goiabeira, em função de diferentes lâminas de irrigação (1144, 1465, 1785 e 2106 mm no primeiro ciclo, e 915, 1308, 1686 e 2093 mm no segundo ciclo produtivo) e níveis de fertilizantes nitrogenados (50, 100, 150 e 200 kg ha-1). Verificou-se efeito apenas isolado dos fatores lâminas de água e adubação nitrogenada sobre as concentrações dos macronutrientes estudados. A lâmina de água exerceu efeito linear positivo na concentração de fósforo e efeito quadrático na concentração de magnésio, nos dois ciclos produtivos, enquanto a adubação nitrogenada não influenciou os teores desses elementos. A concentração de potássio respondeu de forma quadrática à lâmina de água no primeiro ciclo produtivo e à adubação nitrogenada no segundo. A lâmina de água teve efeito linear positivo sobre o cálcio apenas no segundo ciclo; já o efeito da adubação nitrogenada foi quadrático e somente no primeiro ciclo. O efeito da adubação nitrogenada no teor de nitrogênio foi quadrático no primeiro ciclo produtivo e linear positivo no segundo; entretanto, a lâmina de água não exerceu efeito algum.
Análise comparativa de comportamento mecânico de concreto reforçado com macrofibra polimérica e com fibra de aço
Authors: Salvador Renan Pícolo , Figueiredo Antonio Domingues de
Published: September 2013

A utilização de macrofibras poliméricas está amplamente difundida no mercado brasileiro. Entretanto, a caracterização do comportamento mecânico de concretos reforçados com essas macrofibras ainda deve ser mais bem avaliada. Dentre os diversos métodos utilizados para essa finalidade, os ensaios realizados com sistema fechado de controle de velocidade de deslocamento fornecem resultados mais confiáveis. A principal vantagem conferida por esse sistema está na avaliação desses compósitos em baixo nível de fissuração, com maior nível de acurácia. O desempenho desses compósitos foi estudado segundo uma norma recente (ASTM C1609 - 2010) e outra que é uma referência tradicional no Brasil (JSCE-SF4 - 1984). Ambos os procedimentos prescrevem ensaios de flexão de corpos-de-prova prismáticos para determinação da resistência residual pós-fissuração e da tenacidade. Foram estudadas duas fibras: uma macrofibra de polipropileno, nas dosagens de 0,22, 0,33, 0,50, 0,66, 0,82 e 1,0% em volume, e outra de aço, nas dosagens de 0,19, 0,32 e 0,45% em volume. Foi utilizada uma matriz de concreto com resistência média à compressão de 35MPa. Foi verificado que a macrofibra polimérica pode proporcionar o mesmo nível de resistência residual que a fibra de aço, desde que sejam determinados teores com equivalência de desempenho em estudo de dosagem. Além disso, foi comprovada a maior precisão do ensaio utilizando-se a velocidade de deslocamento do corpo-de-prova como parâmetro de controle do ensaio, devido à redução da instabilidade pós-pico, que propiciou melhor avaliação da resistência residual do compósito nos níveis iniciais de deslocamento e fissuração da matriz.
Efeitos da aplicação do laser de baixa potência na regeneração do nervo isquiático de ratos
Authors: Gonçalves Renata Batagini , Marques Jucilene Camilo , Monte-Raso Vanessa Vilela , Zamarioli Ariane , Carvalho Leonardo César , Fazan Valéria Paula Sassoli , Tavares Marcelo Rodrigo
Published: September 2013

Os nervos periféricos sofrem constantes lesões de origem traumática, o que resulta em perdas funcionais. A terapia com laser de baixa potência vem sendo utilizada para minimizar os efeitos maléficos da inflamação e acelerar o processo de cicatrização dos tecidos lesados. Este estudo teve como objetivo verificar o efeito da irradiação do laser 830 nm no comportamento do nervo isquiático de ratos submetido a esmagamento. Foram utilizados 20 ratos, todos tendo tido o nervo isquiático esmagado, divididos em 4 grupos (n=5): P7 e P14, tratamento placebo por 7 e 14 dias; L7 e L14, tratamento por laser (dosagem de 4 J/cm²) por 7 e 14 dias. Os animais dos grupos P7 e P14 foram submetidos aos mesmos procedimentos, mas com o laser desligado. Os parâmetros analisados foram presença de infiltrado inflamatório e fibroblastos, destruição da bainha de mielina e degeneração axonal. Na análise estatística foi observada diferença estatística com relação a três parâmetros: os animais do grupo L14 apresentaram maior quantidade de fibroblastos (p=0,0001), menor degeneração da bainha de mielina (p=0,007) e menor quantidade de infiltrado inflamatório (p=0,001). A aplicação do laser de baixa potência contribuiu para a redução do processo inflamatório decorrente da lesão do nervo isquiático de ratos.
Traços laringais em Latundê (Nambikwára do Norte)
Authors: Telles Stella
Published: September 2013

Este trabalho reflete o status dos traços laringais na língua Latundê, pertencente ao subgrupo Nambikwára do Norte, da família Nambikwára. Os dados foram coletados in loco pela autora entre os anos 1997-2001. Para a análise, considerou-se também a literatura disponível sobre outras línguas da família. O presente artigo está organizado em cinco seções: na primeira, são fornecidas informações sobre a família Nambikwára e os inventários segmentais de três línguas da família; na segunda, são apresentados os quadros fonológicos (consonantal e vocálico) do Latundê; na terceira, encontram-se dados que evidenciam a realização dos traços laringais existentes em consoantes Latundê (glotalização e aspiração) e o contraste do traço creaky voice, nas vogais; na quarta, são feitas considerações sobre a variação laringal no Latundê; finalmente, na quinta seção, são apresentadas reflexões sobre a correspondência entre segmentos com traço laringal do Latundê e do Mamaindê, outra língua Nambikwára do Norte. Os resultados do estudo evidenciaram que no Latundê as consoantes neutralizaram os traços laringais, enquanto que as vogais os mantêm contrastivamente. No interior do ramo do Norte, a correspondência entre consoantes Latundê e Mamaindê parece indicar que a primeira língua é mais inovadora no processo de mudança histórica.
Território cultural e a transformação da floresta em artefato social
Authors: Magalhães Marcos Pereira
Published: September 2013

Em uma das perspectivas da arqueologia da paisagem, todo território cultural é um espaço cujas paisagens são construídas e os ambientes transformados em artefatos sociais. O espaço de manifestação social de uma cultura apresenta locais com ocorrências materiais e recursos naturais diversos, que compõem um território cultural com diferentes ambientes antropogênicos relacionados. Sendo assim, tal como os objetos materiais, as paisagens reproduzem as representações espirituais, políticas e econômicas de uma sociedade. Estudos arqueológicos realizados na região de Porto Trombetas, estado do Pará, têm verificado a maneira como as sociedades relacionadas ao estilo cerâmico Kondurí alteraram os ambientes, interferindo, criando, semeando ou cultivando espécies selecionadas, segundo as suas particularidades culturais. Inventário botânico e escavações arqueológicas realizadas no sítio Greig II, com cultura material Kondurí, indicam como atividades específicas tornam os ambientes mais produtivos e, simultaneamente, familiares, sendo culturalmente identificáveis. Independentemente das possíveis variações estilísticas encontradas na cultura material, acreditamos que as antigas populações amazônicas construíram paisagens onde elas se organizaram e se identificaram social e territorialmente.
A Numerical Study on the Oil-water Separation Process
Authors: Yamaguchi Alan Junji
Published: September 2013

Oil production from the wells results in a mixture of various phases including water, oil, gas, solids like sand and other contaminants such as nitrogen and carbon dioxide. In this way, the primary separation of the crude oil that comes from the reservoir is a very important process in the oil production. For this purpose two main equipments can be employed: gravity separators and hydrocyclones. Despite the simplicity of the mechanism of gravity separator, it is still the best solution when considering the fluctuations of the flow rate and the complexity of the multiphase flow with solid contents. Within this context, the objective of the present work is to perform a numerical analysis of the gravity separator in order to study the primary factors that affect the efficiency of the equipment and to investigate means to improve its productivity. To met the challenging task of modeling multiphase flow inside the equipments with complex geometry, a numerical approach denominated Moving Particle Semi-Implicit (MPS) method is adopted in the present work. MPS is a particle-based Lagrangian method that solves the governing equations of the continuum. It is originally developed to model incompressible free surface flows. For the modeling of the surface tension in the free surface and in the water-oil interface, a inter-particle potential force model is used. For sack of simplicity, two dimensional models of water-oil separation are considered. At first, a simple validation of the numerical approach is carried out. After that, a simplified gravity separator is modeled and the numerical simulations are carried out to investigate the influence of the geometrical configuration on the effectiveness of the separation process.
Analyze of Hydrate Formation with the use of Neural Network Technology
Authors: Kolchin Alexander
Published: September 2013

Hydrate formation is one of the most actual problems in modern gas industry. Gas hydrates are crystalline water-based solids physically resembling ice, in which small non-polar molecules or polar molecules with large hydrophobic moieties are trapped inside "cages" of hydrogen bonded water molecules. In other words, gas hydrates are clathrate compounds in which the host molecule is water and the guest molecule is typically gas or liquid.

Existing and applied models of hydrate formation, as a rule, do not take into account the variety of design features of gas pipelines and the heat exchange between the gas and the environment in the real pipeline constructions. In concordance with foregoing the work held: investigation of the formation process and dissociation of the gas hydrates with due regard for the heat exchange between the gas and the environment and, also, development of the quasionedimensional models of the flow and the heat exchange of the multicomponent medium. The last model analyzes some conditions which could provide us with the hydrate thin-shelled layer instead of spontaneous clathrate formation with further plugging.
Determination of The Dew-Point Pressure (Dpp) For A Gas Condensate Fluid By Genetic Algorithm (Ga)
Authors: Adetiloye Bamisebi
Published: September 2013

In reservoir engineering, a variety of data is needed to accurately estimate reserves and forecast production. Fluid characterization consist of reservoir rock analysis and fluid analysis. The determination of gas condensate dew point pressure, gas specific gravity and producing yield is essential for fluid characterization, gas reservoir performance calculations and the design of production systems. The importance of gas condensate reservoirs has grown continuously and the condensate fluid has gained increased importance.

Traditionally, the dew-point pressure of a gas condensate is experimentally determined in a laboratory in a process called constant mass expansion (CME) test using a visual window-type PVT cell and the constant volume depletion test (CVD). However laboratory measurements, though most reliable, have been found to be laborious, costly and still subject to errors. Hence, the need for other simple and accurate methods of predicting the dew-point pressure (DPP) for a gas condensate. Thus using different equations of states (EOS), several correllations have been developed to predict the DPP of a gas condensate fluid.

This paper therefore seeks to predict the dew point pressure of a gas condensate using genetic algorithm. This is an improved, faster, simple and most accurate method of predicting the dew point pressure.

Genetic algorithm is an adaptive heuristic searching methodology, introduced on the evolutionary ideas of natural selection and genetics, which follows the Charles Darwin's principle of "Survival of the Fittest". Genetic Algorithm represents an intelligent development of a random search within a defined search space (also called as population) to obtain the optimum solution of the problems. Thus, GA would be very effective in carrying out this multi variable optimization.
Managed Pressure Drilling
Authors: Hilts Brandon
Published: September 2013

Managed pressure drilling (MPD) is a drilling technology applied to unconventional prospects where conventional, hydrostatically over-balanced drilling methods encounter problems. MPD finds its greatest success in drilling plays where the margin between pore pressure and fracture gradient is very narrow. The MPD system constitutes several skids containing manifolds, valves, and sensors that plumb into the drilling rig mud circulating system. This system creates a closed atmosphere in the wellbore, which allows MPD technology to achieve a target equivalent circulating density (ECD) by adjusting surface backpressure across the wellhead. Once the target ECD is reached, stable bottom-hole pressure is established.

MPD allows drilling operations to continue "at balance" in oil and gas plays where primary well control cannot meet the needs of pore pressures due to weak fracture gradients in the well profile. MPD technology provides the required calculated surface backpressure to account for drilling fluid density deficiencies. The system is also able to account for lost annular friction pressure during connections as well as variations in bottom-hole pressure due to surge/swab effects resulting from hoisting operations. In addition to the increase in safety as a result of wellbore stability gained from MPD, well economics improve greatly making managed pressure drilling a highly selectable application.
Mapping Geo-Cellular Models to Unstructured Simulation Grids
Authors: Mosser Lukas J.
Published: September 2013

To date, while there are a wide variety of property modeling tools for structured grids, one of the main obstacles to reservoir simulation on unstructured grids is how to transfer these from the geo-cellular grid to an unstructured grid in a consistent and conservative fashion. This needs to be accomplished while honoring layer boundaries, unconformities and faults.

This contribution presents a new method designed to populate unstructured, adaptively refined tetrahedral finite element meshes with highly resolved petrophysical properties from a commercial property modeling tool. Properties from volumetric as well as surface meshes embedded into the 3D domains, are mapped to corresponding tetrahedral and triangular meshes using a barycentric mesh traversal scheme. Solving Laplace equation on the unstructured grid using the modeled property values as constraints, allows us to interpolate them to tetrahedra that do not contain geo-cellular data. The results are of high quality as is indicated by a statistical analysis comparing original with mapped property histograms and variograms. Integral values such as pore volume and original oil in place show a high quality match when compared with an evaluation of the geo-cellular model. The method is demonstrated for the well-known Clyde model including simulations with an original hybrid finite-element finite-volume method.
Study of Kerogen Maturity using Transmission Fourier Transform Infrared Spectroscopy (FTIR)
Authors: Dang Son Thai
Published: September 2013

Maturity of kerogen in shale governs the productivity and generation hydrocarbon type. In the industry, there are generally two methods used to measure kerogen maturity; one is the measurement of vitrinite reflectance, and another is the measurement of Tmax through pyrolysis. However, each of these techniques has its own limits; Vitrinite reflectance measurement cannot be applied to marine shale and pre-Silurian shales lacking plant materials. Tmax measurement is questionable for mature and post-mature samples. Fourier Transmission Infrared Spectroscopy can be applied for both qualitative and quantitative assessment on organics maturity in shale. The technique does not require separating organic matter or identifying macerals. CH2/CH3 index calculated from FTIR spectra is more objective than other measurements. The index increases with maturity (both natural maturation and artificial maturation by hydrous and dry pyrolysis). The new maturity index CH2/CH3 calibrates to Vitrinite Reflectance is: greater than 1.6±0.2 for immature window; from 1.6±0.2 to 1.3±0.3 for oil window; from 1.3±0.3 to 1.13±0.05 for wet gas window; and less than 1.13±0.05 for dry gas window.
Experiment Research Of Tight Sandstone Gas Reservoir Stress Sensitivity Based On The Capillary Bundle Mode
Authors: Zhu Suyang
Published: September 2013

Abstract

The study on tight sandstone gas reservoir stress sensitivity is conductive to set a certain production of gas well and to manage gas field with high efficiency. Traditionally, it is recognized that the stress sensitivity level of tight sandstone is very high based on the experiment report. However, it is not reflected by the production data. In this paper, it is discussed a number of issues which center around the stress sensitivity experiment of tight sandstone, to improve the experiment and develop a new model to evaluate the stress sensitivity level of tight sandstone.

During analyzing the stress sensitivity experiment test, it is found that there exist small interspaces on the core surface which can lead to experiment problems. Based on the study in loose sandstone and analysis on core deformation behavior, two improvements are made, including the pressure drop standard uniform and core ageing treatment. In addition, the capillary bundle model has been developed during the evaluation process, which makes it reasonably possible to deduce the theoretical relationship between the permeability and reservoir pressure drop by the Kozeny-Carman equation to unify and transform the flow in porous media and pipe.

According to the model and improved experiment, it is demonstrated that there exists a linear relation between the permeability and the reciprocal of reservoir pressure drop, which agrees well with experiment observation. Meantime, it can be concluded that and stress sensitivity level of tight sandstone is weak, not as strong as it is reported before.
Economic Study of Miscible CO2 Flooding in a Mature Waterflooded Oil Reservoir
Authors: Salem Said , Moawad Taha
Published: September 2013

One of the first steps in planning EOR research is usually the application of a set of technical screening parameters. These parameters are developed to provide general guidelines for the applicability of a given process to a given oil accumulation or to an inventory of fields with known general characteristics. On the other hand, if an economic screen is carried out, crucial parameters, both technical and economic, may be identified before a significant research commitment is made.

This paper describes the economic feasibility of using CO2 in a mature water flooded oil reservoir. Different cases are used in this study: Continuous water flooding, continuous CO2 flooding and water alternative gas (WAG).

From the economical study on the reservoir, it was found that the reservoir is economically feasible for applying CO2 flooding. The net present value increases with increasing injection rate but there is a limit where increasing the injection rate will reduce the net present value. The optimum injection rate for this reservoir in different techniques is 25 MMscfd; it will give the highest NPV. Results also showed that the second scenario of WAG (two cycles) technique is the best one for this reservoir. The NPV from this technique is equal to $409 million, so the incremental increase of NPV than water flooding is equal to $208 million. From sensitivity analysis, it was concluded that the oil price and CO2 price have a significant effect on the economical feasibility of the application of CO2 flooding and also on the selection of the best technique in CO2 flooding.
Opening the Black Box: Prospects for Using International Large-Scale Assessments to Explore Classroom Effects
Authors: Schmidt William H. , Burroughs Nathan A.
Published: September 2013

In this article, the authors review International Large-Scale Assessment (ILSA)-based research over the last several decades, with specific attention on cross-national analysis of mean differences between and variation within countries in mathematics education. They discuss the role of sampling design and ‘opportunity to learn’ (OTL) indicators to assess the use of ILSAs in examining educational inequalities such as tracking and explore improvements in ILSAs' capacity for studying classroom-level differences in instructional content.
International Large-Scale Assessments: Thermometers, Whips or Useful Policy Tools?
Authors: Lockheed Marlaine E. , Wagemaker Hans
Published: September 2013

Over the past three decades, the number of developing countries participating in International Large-Scale Assessments (ILSAs) has increased dramatically, while developing countries' usage of data from ILSAs for informing educational policy has not been fully realised. In this paper the authors argue that for ILSAs to be useful policy tools, alignment must occur between ILSAs' measurement quality mission and their capacity development mission. They review the use of ILSAs as both ‘whips' and ‘thermometers' and discuss issues in measurement related to the range of skills assessed, their capacity to measure change over time, and the inclusion of other indicators to measure home, classroom and school factors related to student achievement. They then discuss how ILSAs have built assessment capacity in developing countries and what further changes would be needed to improve their utility for policymakers.
Finland Has it All? Examining the Media Accentuation of ‘Finnish Education’ in Australia, Germany and South Korea
Authors: Takayama Keita , Waldow Florian , Sung Youl-Kwan
Published: September 2013

Drawing on the conceptual work of externalisation in comparative education and multi-accentual signs in cultural studies, this article examines how the print news media accentuate ‘Finnish education’ in the process of inserting this external reference into the domestic political discourses around education reform in Australia, Germany and South Korea. The study identifies all articles referencing ‘Finnish education’ that were published from 2000 to 2011 in two widely circulated newspapers with different political orientations in each country. Discourse analysis of the articles shows various ways in which ‘Finnish education’ is accentuated by the newspapers, serving to legitimise different political agendas in education policy debates. It is argued that ‘Finnish education’ has become a ‘projection screen’ for competing conceptions of ‘good education’ and the associated visions of ‘good society’. The authors situate the findings within the ongoing discussion of externalisation, calling for a careful conceptualisation of the role of the media in this line of comparative education scholarship.
Classroom-up Policy Change: Early Reading and Math Assessments at Work
Authors: Gove Amber , Habib Samir , Piper Benjamin , Ralaingita Wendi
Published: September 2013

This article reviews the development of the Early Grade Reading and Mathematics Assessments (EGRA and EGMA), which are locally tailored, timely assessments designed to directly inform policy and instruction for learning improvement, particularly for countries on the lower end of the income spectrum. The history of the design and implementation of the tools, as well as case studies of their use in Egypt and Kenya, are a useful counterbalance to the experience of the more traditional international large-scale assessments (ILSAs) documented in this special issue – in particular for understanding the needs of countries struggling to transform ‘education for all’ into ‘learning for all’.
The Annual Status of Education Report (ASER)
Authors: Banerji Rukmini , Bhattacharjea Suman , Wadhwa Wilima
Published: September 2013

The Annual Status of Education Report (ASER) is a national citizen-led rapid assessment of children's ability to read simple text and do basic arithmetic. ASER is designed and facilitated by the Indian nongovernment organisation Pratham, and has been conducted every year since 2005 by partner organisations in every rural district of India, reaching more than 600,000 children annually. The assessment differs from most other international and national large-scale assessments in several key respects, such as the use of household rather than school-based sampling and the focus on simple tools and indicators that are easy to administer and understand. All ASER metrics, measures and processes are intended to engage ordinary citizens in thinking about and acting to improve basic learning outcomes in India. By conducting a massive national survey each year, ASER has demonstrated that it is possible to use simple, reliable and scientific methods of sampling and assessment on a large scale for high impact at a very low cost. Key to this aspect of ASER has been its ability to mobilise over 25,000 volunteers each year. ASER has been responsible to a large extent for putting the issue of learning on the agenda in India. More recently, the model has been adapted for use in several African and Asian countries. Taken together, these initiatives reached more than a million children in 2012.
Novel Hypothesis to Explain Why SGLT2 Inhibitors Inhibit Only 30–50% of Filtered Glucose Load in Humans
Authors: Abdul-Ghani Muhammad A. , DeFronzo Ralph A. , Norton Luke
Published: September 2013

Inhibitors of sodium-glucose cotransporter 2 (SGLT2) are a novel class of antidiabetes drugs, and members of this class are under various stages of clinical development for the management of type 2 diabetes mellitus (T2DM). It is widely accepted that SGLT2 is responsible for >80% of the reabsorption of the renal filtered glucose load. However, maximal doses of SGLT2 inhibitors fail to inhibit >50% of the filtered glucose load. Because the clinical efficacy of this group of drugs is entirely dependent on the amount of glucosuria produced, it is important to understand why SGLT2 inhibitors inhibit <50% of the filtered glucose load. In this Perspective, we provide a novel hypothesis that explains this apparent puzzle and discuss some of the clinical implications inherent in this hypothesis.
Assessing the Human Gut Microbiota in Metabolic Diseases
Authors: Karlsson Fredrik , Tremaroli Valentina , Nielsen Jens , Bäckhed Fredrik
Published: September 2013

Recent findings have demonstrated that the gut microbiome complements our human genome with at least 100-fold more genes. In contrast to our Homo sapiens–derived genes, the microbiome is much more plastic, and its composition changes with age and diet, among other factors. An altered gut microbiota has been associated with several diseases, including obesity and diabetes, but the mechanisms involved remain elusive. Here we discuss factors that affect the gut microbiome, how the gut microbiome may contribute to metabolic diseases, and how to study the gut microbiome. Next-generation sequencing and development of software packages have led to the development of large-scale sequencing efforts to catalog the human microbiome. Furthermore, the use of genetically engineered gnotobiotic mouse models may increase our understanding of mechanisms by which the gut microbiome modulates host metabolism. A combination of classical microbiology, sequencing, and animal experiments may provide further insights into how the gut microbiota affect host metabolism and physiology.