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  1. Efeito de extratos de plantas medicinais no controle de Colletotrichum acutatum, agente causal da flor preta do morangueiro Effect of plant extract on control of Colletotrichum acutatum the causal agent of the black spot of strawberry

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    Taís Ferreira Almeida

    2009-09-01

    Full Text Available A flor preta do morangueiro, causada por Colletotrichum acutatum, acarreta sérios problemas à cultura. Com o objetivo de verificar a utilização de extratos vegetais no controle da doença, testes "in vitro" foram realizados com 11 extratos vegetais hidroalcoólicos produzidos de plantas utilizadas na medicina popular. Os extratos foram preparados a partir de diferentes partes da planta, de acordo com a espécie, utilizando água e álcool no processo de extração por maceração. Foi verificada a influência dos extratos no crescimento micelial, esporulação e germinaç��o de esporos de C. acutatum, e também no controle do patógeno em folhas e frutos destacados. De acordo com a metodologia utilizada, os extratos vegetais que apresentaram maior eficiência foram os de folha e ramos de Ruta graveolens, Artemisia absinthium e bulbos de Allium sativum, indicando ter essas plantas potencial fungitóxico para o controle de C. acutatum.The black spot of strawberry plants caused by Colletotrichum acutatum, causes serious problems to the culture. To control the disease and minimize the use of fungicides, in vitro assays were accomplished with 11 different plant hydroalcoholic extract from plants species used in the popular medicine. The extracts were produced from plant parts (according to the species using water and alcohol in the extraction process for infusion. The influence of the extracts was verified in the micelial growth, esporulation and germination of the pathogen, besides a test with leaves and outstanding fruits. In agreement with the methodology used in this study, the extracts that showed the highest efficiency were the ones from Ruta graveolens, Artemisia absinthium and Allium sativum, which indicate such plants as potential fungitoxics for the control of C. acutatum.

  2. Efeito de Humoativo comercial na produtividade da couve-flor no Estado de Santa Catarina

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    José Alfredo da Fonseca

    2015-12-01

    Full Text Available O Humoativo comercial é um substrato registrado como produto orgânico, proveniente do tratamento anaeróbico dos resíduos de celulose em lagoas de decantação e posterior compostagem aeróbica, com alta concentração em nutrientes. O objetivo deste experimento foi avaliar, a campo, o efeito da aplicação de doses de Humoativo sobre a produtividade e a absorção de metais pesados por plantas de couve-flor. Foi utilizado delineamento em blocos inteiramente casualizados, com três repetições e sete tratamentos que corresponderam às doses de Humoativo de 17, 34, 51, 68, 85 e 102 t.ha-1, em base seca. O uso do produto como fertilizante para a cultura da couve-flor proporcionou aumentos crescentes das produtividades com o aumento das doses aplicadas. Não houve efeito dos tratamentos sobre os teores de macro e micronutrientes analisados nos tecidos foliares da couve-flor.Effects of Humoativo commercial in cauliflower productivity in Santa Catarina StateAbstract:  Humoativo commercial is a substrate organic derived from the anaerobic treatment of waste cellulose into settling ponds, with high concentrations of nutrients. The objective of this experiment was to evaluate, in field, the effect of doses of Humoativo on productivity and on heavy metal uptake by plants of cauliflower. Design was used randomized blocks with three replications and seven treatments that corresponded to doses of Humoativo of 17, 34, 51, 68, 85 and 102 t.ha-1 in dry basis. The use of the product as fertilizer for the cultivation of cauliflower provided increases in the yield of culture with increasing doses applied. There was no effect of treatments on the concentrations of macro and micronutrients analyzed in the leaves of cauliflower.

  3. A identidade à flor da pele: etnografia da prática da tatuagem na contemporaneidade

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    Andrea Lissett Pérez

    2006-04-01

    Full Text Available No presente artigo, realiza-se uma descrição etnográfica da prática da tatuagem na contemporaneidade, a partir de uma perspectiva que prioriza as noções da prática, das interações e das experiências vividas durante o processo de ser tatuado. A reflexão tenta reconstruir uma visão total da prática da tatuagem que abrange o mundo subjetivo e as dinâmicas sociais como partes constitutivas desse ato. Entre as idéias conclusivas estão, de um lado, o surgimento de uma nova normalidade estética e vivencial no seio da sociedade ocidental e, de outro, a configuração de uma nova subjetividade, a dos "tatuados", como um processo interativo, inovador, emotivo e reflexivo, em que o corpo se converte em uma forma de expressão e construção do sujeito.This article provides a descriptive account of contemporary tattooing, based on a perspective that prioritizes the notion of practice, as well as the interactions and experiences involved in the process of being tattooed. The analysis attempts to rebuild a holistic view of tattooing, combining subjective processes and social dynamics as equally constitutive parts of this activity. Among the conclusions reached are: (a the emergence of tattooing as a new aesthetic norm and a lived experience at the heart of the western society; and (b the configuration of a new subjectivity, the ‘tattooed,’ as an interactive, innovative, emotional and reflexive process in which the body is converted into a form of expressing and constructing the subject.

  4. Interações planta/beija-flor em tres comunidades vegetais da parte sul do Parque Nacional Natural Chiribiquete, Amazonas (Colombia)

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    Liliana Rosero Lasprila

    2003-01-01

    Resumo: Na parte sul do Parque Nacional Natural Chiribiquete, foram estudadas as interações planta/beija-flor em três comunidades vegetais diferenciadas em estrutura e composição florística: bosque de terra firme, bosque baixo das formações rochosas do Tepuy e bosque de "colúvio", que é transicional entre as duas anteriores comunidades. Foi determinada a composição florística das plantas ornitófilas, os atributos florais, fenologia da floração e oferta do recurso floral ao longo do ano nas tr...

  5. Variação estacional da oferta e preços de couve-flor em Minas Gerais

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    Luis Felipe Lima e Silva

    2014-06-01

    Full Text Available Em virtude da variedade de cultivares atualmente disponíveis, de suas diferentes exigências climáticas e das diferenças climáticas entre as várias regiões produtoras, a couve-flor pode apresentar variações estacionais de oferta e de preços ao longo do ano. O objetivo do presente trabalho foi estudar a variação estacional da oferta e dos preços da couve-flor praticados no Estado de Minas Gerais, representados pelas unidades da CEASAMINAS, bem como as componentes dessa oferta para cada principal região abastecedora do Estado, no período de 2005 a 2009. A unidade CEASAMINAS (Grande BH foi responsável por 68% da comercialização anual de couve-flor em Minas Gerais por meio das unidades da CEASAMINAS, que oscilou entre 9.420 e 10.937 toneladas anuais. A quase totalidade de produção proveio de municípios mineiros, localizados em quatro grandes mesorregiões: Região Metropolitana de Belo Horizonte, Campo das Vertentes, Triângulo Mineiro e Vale do Rio Doce, que representaram, respectivamente, 49%, 28%, 9% e 6% da oferta anual. As variações estacionais de oferta refletiram claramente as limitações dos cultivares atualmente disponíveis e a necessidade de novos cultivares que possam tolerar as grandes oscilações de temperatura nos meses de meia estação. Também ficou evidente que, a despeito da disponibilidade de cultivares de verão, a produção de couve-flor ainda é mais baixa nessa época do ano, um reflexo provável da alta precipitação que ocasiona maiores perdas por doenças na lavoura e em pós-colheita.

  6. A arte de ser Beija-Flor na tripla jornada de trabalho da mulher

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    Adriane Vieira

    2013-06-01

    Full Text Available Com presença expressiva no mercado de trabalho, as mulheres vêm ampliando continuamente sua participação nos mais diversos cargos e funções, no entanto continuam sendo as principais responsáveis pelas atividades do lar e pelo cuidado dos filhos. A situação agrava-se com a crescente demanda por qualificação, exigindo que essas trabalhadoras cumpram, muitas vezes, três jornadas de trabalho: profissional, familiar e educacional. Este estudo teve como objetivo analisar os mecanismos de dominação refletidos nas ações de mulheres que "conciliam" as atividades profissionais, o cuidado com a família e as exigências da educação continuada, utilizando como referência principal o trabalho de Pierre Bourdieu. Trata-se de uma pesquisa qualitativa, cuja coleta de dados ocorreu através de entrevista, buscando obter as histórias orais temáticas de cinco mulheres. Os relatos foram submetidos à técnica de análise do conteúdo e os resultados revelam que a busca pela qualificação deriva da preocupação com a empregabilidade e que a disputa profissional está ligada não apenas ao gênero, mas também à concorrência com profissionais mais jovens. Apesar de as mulheres fazerem referência ao início de uma revisão da divisão sexual de tarefas do lar, a empregada doméstica ainda se revela fundamental nesse processo de delegação e de conciliação. Para se dedicar aos estudos, elas abdicaram do lazer, não como um sacrifício, mas sim como um ato de nova significação das coisas. Tal qual beija-flor, que conjuga trabalho e reprodução das espécies botânicas, elas esperam conciliar as jornadas com rapidez, mas também com graça e leveza.

  7. Composição florística e estrutural da vegetação de restinga do Estado do Piauí

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    Francisco Soares Santos Filho

    2008-01-01

    Restinga é vegetação assentada sobre neossolos quartzarênicos do Quaternário e sua composição florística é considerada uma extensão da floresta atlântica ou de ecossistemas adjacentes. A presente tese traz dois trabalhos realizados nas restingas do estado do Piauí, cujo litoral pertence à porção setentrional do litoral nordestino. Este estudo foi composto por dois capítulos. O primeiro tratou de verificar se as restingas do Piauí apresentam composição florística originada em seus ecossiste...

  8. Composição florística da floresta estacional decídua montana de Serra das Almas, CE, Brasil

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    Lima,Jacira Rabelo; Sampaio,Everardo Valadares de Sá Barretto; Rodal,Maria Jesus Nogueira; Araújo,Francisca Soares

    2009-01-01

    No domínio semi-árido brasileiro, a flora das bacias sedimentares ainda é pouco conhecida, mas os levantamentos já existentes indicam que há grande heterogeneidade florística e fisionômica. Mesmo áreas geográficas próximas podem apresentar dissimilaridade florística. Visando testar esta hipótese, a composição florística e o espectro biológico da floresta estacional decídua de Serra das Almas, estado do Ceará, foram analisados e comparados com os de 14 áreas sedimentares no Nordeste. Foram enc...

  9. Efeito residual da jitirana, flor-de-seda e mata-pasto no cultivo da rúcula em sucessão a beterraba

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    Alany Moisa Bezerra Almeida

    2015-05-01

    Full Text Available O efeito residual da adubação anterior em cultivos subsequente é de suma importância, uma vez que a fertilização do solo em uma atividade tão intensa, como a olericultura, aumentaria o custo de produção sempre que fosse implantada uma nova cultura. Este trabalho foi conduzido na Fazenda Experimental Rafael Fernandes, localizada no distrito de Alagoinha, zona rural de Mossoró-RN, no período de novembro a dezembro de 2011. Objetivou-se avaliar o efeito residual da jitirana, flor-de-seda e mata-pasto no cultivo da rúcula em sucessão a beterraba. A beterraba foi plantada em parcelas de 1,2 x 1,2 m e adubado com espécies espontâneas, nas quantidades: 0,6; 1,2; 1,8; 2,4 e 3,0 kg m-2 de canteiro. Após a retirada da beterraba, semearam-se sementes de rúcula nas parcelas referente aos tratamentos acima citados. O delineamento experimental foi em blocos casualizados com três repetições, no esquema fatorial 5 x 3, sendo cinco quantidades e três tipos de adubos verdes (jitirana; flor-de-seda e mata-pasto. A cultivar de rúcula plantada foi a Cultivada. As características avaliadas foram: altura e número de folhas por planta, massa fresca, número de molho de rúcula e massa seca. Houve interação dos fatores estudados para massa fresca de rúcula e número de molhos. O efeito residual na quantidade de 3,0 kg m-2 de canteiro contribuiu para a massa fresca de rúcula da ordem de 762; 684 e 713 g m-2 de canteiro, equivalente a 6,0; 5,0 e 5,0 molhos de rúcula para jitirana, flor-de-seda e mata-pasto, respectivamente. Jitirana, flor-de-seda e mata-pasto são espécies promissoras para ser utilizadas como adubo verde na produção de hortaliças.

  10. Florística e fitossociologia em um trecho de restinga no Litoral Norte do Estado da Bahia

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    Christiano Marcelino Menezes

    2011-11-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2012v25n1p31 As restingas são ambientes geologicamente recentes e as espécies que as habitam são típicas de ecossistemas adjacentes como as Florestas Ombrófilas, as Matas de Tabuleiro e a Caatinga, sendo este, o aspecto mais importante na sua composição de espécies, que é composta por diversas formas biológicas, tais como árvores, arbustos, herbáceas eretas e reptantes. O estudo foi realizado no Município de Mata de São João na vila de Praia do Forte, localizada ao longo do Litoral Norte do Estado da Bahia. Com o objetivo de avaliar se há existência de diferentes comunidades vegetais em um trecho de restinga, foram locadas quatro transecções de 200m com cinco unidades amostrais de 100m2 cada. Ao final do estudo foram amostrados 1.640 indivíduos distribuídos em 68 espécies. Os dados florísticos e fitossociológicos associados à análise de Cluster apontam a existência de duas comunidades vegetais distintas, sendo elas uma Mata de Restinga (Transecções 3 e 4 e uma Restinga em Moitas (Transecções 1 e 2. Uma elevada diversidade de espécies foi detectada nas transecções 1 e 2 (H’ = 3,882 e 3 e 4 (H’ =3,835, além de uma diferença significativa na composição das espécies entre elas (p < 0,001. As famílias mais representativas em número de espécies foram: Myrtaceae, Rubiaceae e Malpighiaceae.

  11. Florística na Reserva Particular do Patrimônio Natural Complexo Serra da Farofa, estrutura e efeitos ambientais da antropização na comunidade arbustivo-arbórea, Santa Catarina, Brasil

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    Floriani, Mireli Moura Pitz

    2015-01-01

    A Floresta Ombrófila Mista (FOM) pertence ao Bioma Mata Atlântica e trata-se de uma formação florestal rica em espécies vegetais endêmicas, ocorrente preferencialmente na região Sul do Brasil. O trabalho teve como objetivo conhecer a composição florística, a estrutura e os efeitos ambientais da antropização na comunidade arbustivo-arbórea na Reserva Particular do Patrimônio Natural Estadual Complexo Serra da Farofa (Bloco VI) no município de Rio Rufino, Santa Catarina. O ...

  12. Levantamento florístico da Área de Proteção Ambiental de Jericoacoara, Ceará

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    Matias Lígia Queiroz

    2001-01-01

    Full Text Available Estudou-se a composição florística da Área de Proteção Ambiental de Jericoacoara, Estado do Ceará, nordeste do Brasil (2°47' - 2°51'S e 40°36' - 40°24'W. O clima da região é do tipo Aw` (segundo a classificacação de Köppen com temperaturas médias oscilando entre 35°C e 22°C, com chuvas de verão (dezembro a junho, possuindo um período de estiagem de 5 a 6 meses, frequentemente interrompido por chuvas ocasionais em setembro e outubro, e apresenta índice xerotérmico de Gaussen variável entre 100 e 150. As formações vegetacionais estudadas foram: vegetação com influência flúvio-marinha ou manguezal em estuários e na região de pós-praia e vegetação com influência marinha ("restingas". Foram identificadas 87 espécies, 77 gêneros e 39 famílias. As famílias que apresentaram maior riqueza específica foram: Poaceae (13%, Cyperaceae (13%, Fabaceae (6%, Amaranthaceae (6% e Rubiaceae (6%. Alguns aspectos relacionados a conservação ambiental na APA são discutidos.

  13. CRESCIMENTO DA PARTE AÉREA DE MUDAS DE COUVE-FLOR PRODUZIDAS EM DIFERENTES SUBSTRATOS EM SISTEMA AGROECOLÓGICO

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    Julio Cesar Gradice Saluci

    2017-04-01

    Full Text Available A agricultura exerce grande expressividade no desenvolvimento social, político e econômico do Brasil. Contudo existe constate crescimento na procura e exigência por alimentos mais saudáveis, que podem ser produzidos com técnicas da agroecologia. Objetivou-se com este trabalho avaliar diferentes substratos na produção de mudas de couve-flor. O experimento foi em DIC, no esquema fatorial (4x4 avaliando 7 plantas em cada tratamento na fase final de mudas. Os resultados encontrados para a parte aérea, demostraram desenvolvimento satisfatório para a cultura nos substratos orgânicos, em relação ao comercial, sendo que foi observado superioridade das variáveis quando utilizou-se o vermicomposto como substrato, independente das concentrações usadas, entretanto não houve diferença entre as concentrações usadas para esse substrato. Os substratos orgânicos proporcionaram boa produção. Dentre estes substratos destacou-se o vermicomposto.

  14. Aspectos florísticos e fitossociológicos da reserva Capão de Tupanciretã, Tupanciretã, RS, Brasil.

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    Suzana Ferreira da Rosa

    2008-01-01

    Full Text Available Este trabalho foi realizado na Reserva Capão de Tupanciretã, município de Tupanciretã (RS, em uma área com 8 hectares pertencente à Fundação de Pesquisa Agropecuária do Rio Grande do Sul (FEPAGRO. O objetivo do trabalho foi avaliar a composição florística e estrutura fitossociológica da floresta. Utilizaram-se dez parcelas de tamanho 10 x 20 m distribuídas sistematicamente na área. Nessas parcelas, foram medidos e identificados todos os indivíduos com DAP maior ou igual a 5 cm. Dentro das parcelas principais, alocaram-se subunidades de 5 x 5 m para avaliar o componente arbustivo (DAP entre 1 e 5 cm e de 2 x 2 m para a regeneração natural (DAP menor que 1 cm e altura superior a 30 cm. Os resultados foram analisados usando o programa FITOANALISE, calculando-se os parâmetros fitossociológicos tradicionais de densidade, dominância, freqüência, valor de importância, valor de cobertura e índice de diversidade. As espécies com maior representatividade no componente arbóreo da floresta foram Camboatá-vermelho (Cupania vernalis Cambess. e o Branquilho (Sebastiania commersoniana (Baill. L. B. Sm. & Downs. No componente arbustivo e na regeneração, as espécies que apresentaram o maior número de indivíduos foram Camboatá-vermelho (Cupania vernalis Cambess., Primavera (Brunfelsia australis Benth., Chal-chal (Allophylus edulis (A. St.–Hil, Cambess. & A. Juss. e Canela-amarela (Nectandra lanceolata Nees

  15. Causality

    Science.gov (United States)

    Pearl, Judea

    2000-03-01

    Written by one of the pre-eminent researchers in the field, this book provides a comprehensive exposition of modern analysis of causation. It shows how causality has grown from a nebulous concept into a mathematical theory with significant applications in the fields of statistics, artificial intelligence, philosophy, cognitive science, and the health and social sciences. Pearl presents a unified account of the probabilistic, manipulative, counterfactual and structural approaches to causation, and devises simple mathematical tools for analyzing the relationships between causal connections, statistical associations, actions and observations. The book will open the way for including causal analysis in the standard curriculum of statistics, artifical intelligence, business, epidemiology, social science and economics. Students in these areas will find natural models, simple identification procedures, and precise mathematical definitions of causal concepts that traditional texts have tended to evade or make unduly complicated. This book will be of interest to professionals and students in a wide variety of fields. Anyone who wishes to elucidate meaningful relationships from data, predict effects of actions and policies, assess explanations of reported events, or form theories of causal understanding and causal speech will find this book stimulating and invaluable.

  16. Produtividade e qualidade da flor-de-seda em diferentes densidades e sistemas de plantio Productivity and quality of rooster tree in different planting densities and planting systems

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    Maria Verônica Meira de Andrade

    2008-01-01

    Full Text Available Avaliou-se o efeito de dois sistemas de plantio (sem camalhão e com camalhão e de três espaçamentos (1,0 × 1,5 m; 1,5 × 2,0 m; e 2,0 × 2,0 m sobre a qualidade e a produtividade de flor-de-seda aos 60 dias de rebrotação. Utilizou-se o delineamento experimental com blocos casualizados em esquema fatorial 2 × 3 (dois sistemas de manejo do solo e três densidades de plantio com cinco repetições, em parcelas subdivididas no espaço e no tempo. Plantas escolhidas aleatoriamente foram cortadas, separadas por tratamento e analisadas quanto aos teores de matéria seca (MS, matéria orgânica (MO, cinzas, extrato etéreo (EE, proteína bruta (PB, fibra em detergente neutro (FDN, fibra em detergente ácido (FDA, celulose, hemicelulose, lignina, carboidratos não-fibrosos (CNF e carboidratos totais (CT e quanto à produtividade (kg MS/ha. Os sistemas de manejo do solo e as densidades de plantio não influenciaram a composição em MO, cinzas, FDN, EE, lignina, celulose, CNF e CT. As densidades de plantio influenciaram o teor de hemicelulose e FDA. O sistema de manejo do solo com camalhão teve efeito linear decrescente sobre o teor de PB. A maior produtividade de MS (699,72 kg/ha da flor-de-seda foi verificada no sistema de plantio mais adensado (1,0 m × 1,5 m e correspondeu a 6.666 plantas/ha.The effect of two soil handling systems was evaluated (without furrow and with furrow, three spacing (1.0 m × 1.5 m; 1.5 m × 2.0 m and 2.0 m × 2.0 m on the quality and the productivity of rooster tree 60 days after cut. It was used a split-plot (space and time factorial arrangement in a randomized block design. Factors were two soil handling systems and three planting densities (2 × 3 with five replications per treatment. Plants chosen randomly were cut, separated in accordance with treatments and analyed the contents of dry matter (DM, organic matter (OM, mineral matter (MM, ether extract (EE, crude protein (CP, neutral detergent fiber (NDF, acid

  17. Variações na composição e estrutura da vegetação permitem detectar agrupamentos florísticos em uma Floresta Subtropical Atlântica no Sul do Brasil?

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    João Paulo de Maçaneiro

    2016-12-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2016v29n4p43 As variações da vegetação em função da posição topográfica têm despertado o interesse dos pesquisadores. Entretanto, poucos estudos verificaram as associações florísticas formadas pela posição topográfica de uma encosta. Neste trabalho, analisamos se as variações na vegetação permitem detectar agrupamentos florísticos em uma Floresta Pluvial Subtropical. A vegetação foi amostrada em 25 parcelas de 400 m² distribuídas sistematicamente, onde foram medidos os indivíduos com DAP ≥ 5,0 cm. Amostramos 1.727 indivíduos e 144 espécies. A ordenação NMDS segregou três grupos em função da posição topográfica da encosta (Monte Carlo, P ≥ 0,05; ANOSIM, P < 0,001. Euterpe edulis e Sloanea guianensis se destacaram nos terços inferior e médio da encosta, enquanto Ocotea aciphylla e Alchornea triplinervia se destacaram no terço superior. Algumas espécies se mostraram indicadoras dos setores analisados, como é o caso de Actinostemon concolor e Alsophila setosa no terço inferior, Cyathea corcovadensis e Rudgea recurva no terço médio e Myrcia pulchra e Podocarpus sellowii no terço superior. Nossos resultados indicaram que as variações florísticas e estruturais observadas por Veloso e Klein (1959 e Klein (1980; 1984 para o Vale do Itajaí em Santa Catarina apresentam validade estatística nos dias atuais, pois verificamos a formação de diferentes grupos de acordo com a posição topográfica da encosta.

  18. Aspectos florísticos da vegetação de restinga no litoral de Pernambuco Floristics aspects of restinga vegetation in the coast of Pernambuco - Brazil

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    Ana Cláudia Sacramento

    2007-12-01

    Full Text Available As zonas costeiras acolhem quadros de alta riqueza e relevância ecológica que as qualificam como importante ecossistema para conservação. O objetivo deste estudo foi listar as espécies que compõem a restinga da praia do Paiva e descrever a sua fisionomia. A área de restinga compreende 147 ha, situa-se no Município do Cabo de Santo Agostinho, PE, sob as coordenadas 08º07'30"S e 35º00'55"W. As coletas florísticas foram realizadas durante 28 meses, em todos os estratos. O solo foi classificado como Neossolo Quartzarênico; foram determinadas duas fisionomias: a floresta não-inundável e o fruticeto aberto não-inundável. Foram listadas 124 espécies, distribuídas em 103 gêneros e 55 famílias. As famílias com maior número de espécies foram Myrtaceae, com 11 espécies, Cyperaceae (10, Fabaceae (8, Euphorbiaceae (7, Rubiaceae (6 e Asteraceae (5. As espécies Anacardium occidentale, Tapirira guianensis, Chamaecrista ramosa, Protium heptaphyllum, Byrsonima sericea, Myrcia rotundifolia e Marlierea schotti são encontradas na maioria das restingas do Nordeste. No entanto, devido à incipiência dos estudos na Região não foram verificadas espécies endêmicas.The high biodiversity and richness of the coastal zone make it an important ecosystem to be preserved. The aim of this study is to list the species composition of the restinga area (147 ha. of Paiva beach, in Cabo de Santo Agostinho-Pernambuco (08º07'30"S and 35º00'55"W and describe the physiognomies. Floristic survey was carried out for 28 months for all strata. The soil was classified as Quartzarenic Neosoil and two physiognomies were determined: unflooded forest and unflooded open shrubby vegetation. One hundred-twenty-four species were recorded, distributed in 103 genera and 55 families. The families with the highest number of species were: Myrtaceae (11, Cyperaceae (10, Fabaceae (8, Euphorbiaceae (7, Rubiaceae (6 and Asteraceae (5. Anacardium occidentale, Byrsonima sericea

  19. Produtividade da couve-flor em função da idade de transplantio das mudas e tamanhos de células na bandeja Cauliflower production depending on age of seedling and cell size of the trays

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    Maria Carolina Godoy

    2005-07-01

    Full Text Available O experimento foi realizado de novembro de 2000 a abril de 2001, na UNESP em São Manuel (SP. Estudou-se o efeito do tamanho da célula da bandeja de poliestireno expandido e a idade de transplantio das mudas sobre a produção de couve-flor, híbrido Shiromaru II. Usaram-se bandejas com 128 e 288 células, correspondentes a 34,6 e 9,7 cm³/célula, respectivamente, e mudas transplantadas aos 27, 34, 41 e 48 dias após a semeadura. Os tratamentos foram arranjados como fatorial 2 x 4, dispostos no delineamento de blocos casualizados, com cinco repetições. Foram avaliados, por ocasião do transplantio, o número de folhas, peso fresco, peso seco e área foliar das mudas. A parcela experimental no campo foi constituída por dez plantas. Nas colheitas, avaliaram-se a porcentagem de plantas com cabeça comercial e nestas, o número de folhas, peso fresco e diâmetro da cabeça. A produção total por parcela foi obtida com a soma do peso fresco de todas as cabeças consideradas comerciais. A produção de mudas em bandejas com 128 células proporcionou maior porcentagem de plantas comerciais (64% relativamente às bandejas com 288 células (45%, maior peso médio de cabeça (337 g na bandeja com 128 e 247 g na bandeja com 288 células e maior produção de plantas comerciais (36,9 t/ha em bandeja de 128 células e 19,9 t/ha em bandeja de 288 células. As mudas transplantadas com 32 dias apresentaram maior peso médio de cabeça (319 g. Concluiu-se ser recomendável produzir mudas de couve-flor em bandejas com 128 células.The experiment was carried out from November/2000 to April/2001, in São Manuel, São Paulo State, Brazil. The effect of cell size of two polyestyrene trays and age of seedling at transplanting date was observed, on the production of cauliflower, hybrid Shiromaru II. Trays with 128 and 288 cells, corresponding to 34.6 and 9.7 cm³/cell, respectively, were used with seedlings transplanted at 27; 34; 41 and 48 days after sowing date

  20. Análise das variações florísticas e estruturais da comunidade arbórea de um fragmento de floresta semidecídua às margens do rio Capivari, Lavras-MG

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    Souza Josival Santos

    2003-01-01

    Full Text Available Realizou-se um estudo das variações florísticas e estruturais da comunidade arbórea em um fragmento de Floresta Estacional Semidecídua situado às margens do rio Capivari, em Lavras, Minas Gerais, com o objetivo de analisar as correlações entre variáveis ambientais (edáficas, topográficas e morfométricas do fragmento e a distribuição das espécies arbóreas. Procurou-se, também, ampliar o conhecimento sobre a composição florística e a estrutura fitossociológica das comunidades arbóreas da região do alto rio Grande. As espécies arbóreas foram amostradas em coletas extensivas na área e intensivas dentro de 28 parcelas de 20 20 m, tendo sido considerados apenas os indivíduos com DAP > 5 cm. As parcelas foram distribuídas em cinco transeções, dispostas paralelamente à inclinação predominante do terreno. As variáveis ambientais foram obtidas por meio do levantamento topográfico do fragmento e de análises químicas e granulométricas de amostras dos solos. As correlações entre distribuição das abundâncias das espécies e as variáveis ambientais nas parcelas foram avaliadas por análise de correspondência canônica (CCA. A listagem florística registrou 166 espécies, sendo 140 encontradas dentro das parcelas. A comunidade arbórea apresentou um elevado índice de diversidade de Shannon (H' = 4,258 nats/indivíduo, correlacionado à baixa dominância ecológica (alta equabilidade de Pielou, J' = 0,862 e, possivelmente, à alta heterogeneidade ambiental local. A CCA demonstrou que a heterogeneidade ambiental do fragmento é caracterizada principalmente pela topografia acidentada e pelas variações de fertilidade, granulometria e regime hídrico dos solos, sendo este último o mais fortemente correlacionado com a distribuição das espécies. Muitas espécies arbóreas mostraram clara preferência por dois habitats: a baixa encosta, com solos mais úmidos e férteis, e a alta encosta, com solos menos úmidos e f

  1. JOHN SEARLE SOBRE A IDENTIDADE E A EFICÁCIA CAUSAL DA CONSCIÊNCIA

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    Tárik de Athayde Prata

    2010-01-01

    Full Text Available O texto discute os problemas em que se envolve o naturalismo biológico deJohn Searle ao defender (a a eficácia causal da consciência, (b a identidade dascapacidades causais da consciência e das capacidades causais dos processos cerebrais e(c a irredutibilidade ontológica da consciência. Essas três teses parecem implicar que aconsciência é e não é idêntica à atividade cerebral. Uma solução poderia ser encontradase o autor discutisse mais cuidadosamente a noção de identidade.

  2. Florística e estrutura do componente arbustivo-arbóreo de uma floresta higrófila da bacia do rio Jacaré-Pepira, SP, Brasil

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    Marques Márcia C. M.

    2003-01-01

    Full Text Available As florestas higrófilas são formações ribeirinhas caracterizadas por ocorrerem em solo permanentemente encharcado e restritas a pequenos fragmentos junto a outros tipos vegetacionais. Neste trabalho caracterizaram-se a florística e a estrutura do componente arbustivo-arbóreo (plantas com DAP>5cm de uma área de 0,36ha de floresta higrófila localizada em Brotas (48º06'W 22º16'S, 470m.s.m., Estado de São Paulo, usando-se método de parcelas (total de 24 parcelas. No total foram amostrados 735 indivíduos, distribuídos em 32 famílias e 51 espécies. As espécies que se destacaram na comunidade devido aos elevados valores de importância foram Calophyllum brasiliense Camb., Protium almecega L. Marchand, Podocarpus sellowii Klotzch., Tapirira guianensis Aubl. e Dendropanax cuneatum DC. Decne. & Planch. O índice de diversidade de Shannon foi igual a 2,81, valor pouco superior aos descritos para florestas semelhantes. Na comunidade, as espécies generalistas com relação ao encharcamento do solo e as de solo drenado contribuíram na riqueza total (juntas 62% do total de espécies amostradas, enquanto as espécies de solo encharcado tiveram maior contribuição na composição da dominância (66% da dominância total e densidade (67% da densidade total relativas. A diversidade de situações topográficas e a entrada de espécies da vegetação do cerrado adjacente permitiram que espécies com diferentes exigências hídricas se estabelecessem na área relativamente pequena da floresta e influenciaram fortemente a florística e estrutura da comunidade.

  3. Florística e classificação da regeneração natural em Floresta Ombrófila Mista na Floresta Nacional de São Francisco de Paula, RS.

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    Igor da Silva Narvaes

    2009-10-01

    Full Text Available Normal 0 21 MicrosoftInternetExplorer4 Na floresta Ombrófila Mista, a regeneração natural é pouco estudada. No Rio Grande do Sul, em conseqüência da ação antrópica, essas florestas se encontram sob diferentes condições de alteração, em alguns casos formando fragmentos. O estudo teve como objetivo analisar a florística da regeneração natural e verificar a ocorrência de grupos florísticos de uma área onde não foram constatadas alterações intensas. A área com 1606,69 ha localiza-se na Floresta Nacional de São Francisco de Paula (entre 29° 23' e 29° 27' S; 50° 23' e 50° 25' W, no município de São Francisco de Paula, RS. No estudo, foram selecionadas seis parcelas permanentes de crescimento do PELD (Projeto Ecológico de Longa Duração cuja vegetação foi inventariada, utilizando-se dez faixas paralelas entre si e perpendiculares à direção da posição topográfica, as quais apresentaram 10 m de largura e 100 m de comprimento, subdivididas em dez unidades de 100 m² onde foram sorteadas três unidades amostrais por faixa para identificação e medição (altura e circunferência de indivíduos com Cap maior ou igual a 3 cm e menor de 30 cm. Os cipós, trepadeiras e ervas também tiveram suas circunferências medidas e identificados até o nível de espécie, quando possível. Os dados de densidade por espécie formaram uma matriz (180x70 utilizada na análise multivariada. A presença de agrupamento de vegetação em estado de regeneração natural no interior da floresta foi testada pelo Método TWINSPAN (Two-way indicator species analysis. Constatou-se a existência de três grupos ecológicos (G-1, G-2 e G-3. O G-1 foi caracterizado por boa disponibilidade hídrica, por possuir características ambientais intermediárias e por situar-se na posição topográfica referente à encosta média; G-2 ocorreu na encosta inferior da floresta, apresentando forte influência da umidade e sujeita a alagamentos espor

  4. Composição florística e estrutura comunitária da floresta de galeria do córrego da Paciência, Cuiabá, (MT Floristic composition and community structure of a gallery forest along the Córrego da Paciência, Cuiabá, Mato Grosso, Brazil

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    Ary Teixeira de Oliveira-Filho

    1989-07-01

    Full Text Available A floresta de galeria de um dos braços do córrego da Paciência, no sopé da chapada dos Guimarães, Mato Grosso (15º 21'S. 55º 49' W, foi inventariada por meio de 67 parcelas de 30m² (0,201 ha, sendo amosdos os indivíduos com circunferência ao nível do solo > 9cm em três setores da floresta; Nascentes, Vereda e Cachoeira. Foram calculados os parâmetros fitossociológicos das espécies e das famílias botânicas para toda a área amostral e para cada um dos três setores da floresta. Foram obtidas medidas de dissimilaridade florística e estrutural entre os três setores amostrais e medidas de dissimilaridade florística entre a floresta do presente estudo e cinco outras florestas riparias do Distrito Federal e dos estados de São Paulo e Mato Grosso. As seis florestas apresentaram entre si índices muito altos de dissimilaridade florística, embora algumas delas apresentassem espécies em comum entre as mais abundantes. Os três setores amostrais mostraram igualmente uma considerável dessemelhança florística e estrutural entre si. O clima, os solos e a geomcrfologia das bacias hidrográficas são evocados como responsáveis pelas diferenças interregionais entre as florestas riparias. Já as dessemelhanças intrarregionais podem ser atribuídas à fertilidade dos solos e, sobretudo, ao regime de água nos solos e nos próprios rios, os quais, por sua vez, variam com a topografia local. Os padrões de distribuição espacial marcadamente diferentes que podem ser observados para várias espécies de árvores podem ser atribuídos à elevada heterogeneidade ambiental, peculiar às florestas de galeria.The gallery forest which occurs along one of the branches of the Córrego da Paciência, southern Mato Grosso, Brazil (15º 21'S, 55º 49'W, was surveyed by 67 plots of 30m² each (0.201 ha. Individuals > 9cm in circumference at ground level were recorded. Three sites of the forest were sampled: Nascentes, Vereda and Cachoeira

  5. Effect of alcoholic extract of guaco (Mikania glomerata on the control of dark rot (Xanthomonas campestris pv. campestris in cauliflower/ Avaliação da eficácia da tintura etanólica de guaco (Mikania glomerata no controle da podridão negra (Xanthomonas campestris pv. campestris em couve-flor

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    Kátia Regina Freitas Schwan-Estrada

    2006-06-01

    Full Text Available With the use of irrigation and new hybrids of cauliflower, it is possible to get production during all the year with hight yield. However, the crop has been affected by diseases, as the dark rot caused by X. campestris pv. campestris. The objective of this research work was to study the potential of Mikania glomerata for the control of this disease. Alcoholic extract 50 ºGL of M. glomerata was evaluated regarding to: in vitro antimicrobial activity through bacterial growth in 100, 250, 500 and 1000 mg L-1 of the alcoholic extract; induction of local or systemic resistance in 25 days old cauliflower, with spray of alcoholic extract concomitantly and three days before the inoculation with the pathogen (water and bordeau mixture were used as control; peroxidases activity in leaves of cauliflower treated and not treated, and harvested concomitantly, 24, 48 and 72 hours after spraying the alcoholic extract and also after inoculation. The alcoholic extract of M. glomerata showed inhibition of the bacterial growth in vitro at the concentrations of 250, 500 and 1000 mg L-1. The concentrations of 500 mg L-1 and 1000 mg L-1 inhibited 24% and 38% of the bacterial growth. This inhibition could be due to antibacterial compounds in the alcoholic extract. An inhibition of the disease in vivo occurred only in the leaves treated with 100 and 500 mg L-1 of alcoholic extract when applied concomitantly with the bacteria. This result was similar to bordeau mixture, indicating a control by direct antimicrobial activity. There was no systemic resistence induction for all treatments. The peroxidases induction was due to infectious pathogen process and not to the treatments with alcoholic extract. The results indicate the potential of M. glomerata alcoholic extract for the preventive control of cauliflower dark rot disease.Com a prática da irrigação e novos híbridos de couve-flor, é possível produzir durante todo o ano e com alta produtividade. Mas, a cultura tem

  6. Avaliação de larvicidas de origem microbiana no controle da traça-das-crucíferas em couve-flor Evaluation of microbiological larvicides to control diamondback moth in cauliflower

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    Daniel G.S. Dias

    2004-09-01

    Full Text Available Dois inseticidas biológicos à base de Bacillus thuringiensis subspécies kurstaki (Btk e aizawai (Bta e um inseticida não sistêmico de origem biológica, à base de spinosad, foram avaliados em campo contra a traça-das-crucíferas, Plutella xylostella (L.(Lep.: Plutellidae, em cultivo de couve-flor. O experimento foi realizado em Brazlândia, DF, em uma área de produção regular de hortaliças. A lavoura foi conduzida segundo manejo indicado para a região, sem qualquer intervenção que não o controle da praga. O experimento foi realizado no período de julho a setembro de 2002. O delineamento foi de blocos ao acaso, com quatro tratamentos e quatro repetições. Os produtos foram aplicados em função da média do número de furos produzidos pela praga, presentes nas quatro folhas centrais das plantas, sendo os diferentes tratamentos avaliados semanalmente. Quando a média do número de furos atingia valor igual ou superior a seis, os produtos eram aplicados. Adotando-se este procedimento, aplicou-se três vezes o inseticida spinosad e seis vezes os inseticidas Btk e Bta. Os três tratamentos com inseticidas não diferiram entre si, mas diferiram significativamente da testemunha quanto à produção. As áreas tratadas com Btk produziram 78,1% de cabeças comercializáveis, as tratadas com Bta 76,5% e as tratadas com spinosad 75,5%. No controle houve perda de 34,4% da produção. A utilização dos produtos aumentou a receita da cultura da couve-flor em relação à testemunha, nos valores de R$ 2.505,19 com o Btk, R$ 1.954,55 com o Bta e R$ 1.891,65 com spinosad.Two bioinsecticides based on Bacillus thuringiensis sub species kurstaki (Btk and aizawai (Bta and non-systemic insecticide of biological origin based on spinosad were evaluated on cauliflower crop for diamondback moth, Plutella xylostella (L. (Lep.:Plutellidae control. The experiment was conducted in a vegetable production area of Brazlândia, Brazil. The crop was conducted

  7. El daño y el nexo causal en la perdida de oportunidad

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    Herrera Montañez, Diego Alejandro

    2016-01-01

    El presente escrito se ocupa de estudiar el nexo de causalidad como elemento estructural de la responsabilidad cuando éste es difuso. Para ello, se pretende abordar la pérdida de la oportunidad como una teoría especial de causalidad que tiene lugar cuando el nexo causal no resulta claro, lo cual contradice la tesis preponderante de la doctrina y la jurisprudencia tradicional según la cual, la pérdida de la oportunidad es un criterio autónomo del daño. En su contenido se realiza una explic...

  8. Estrutura e composição florística de quatro formações vegetais de restinga no complexo lagunar Grussaí/Iquipari, São João da Barra, RJ, Brasil

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    Assumpção Jorge

    2000-01-01

    Full Text Available Foi estudada a vegetação de restinga do complexo lagunar Grussaí/Iquipari (21°44'S; 41°02'O, que compreende a bacia das lagunas de Grussaí e Iquipari, com aproximadamente 4.800ha. Uma transecção de 25ha (2500x100m foi delimitada no sentido mar/interior e coletas botânicas realizadas entre os anos de 1995 e 1997. As quatro unidades fisionômicas ocorrentes na área foram estudadas e, através do Índice de Valor de Cobertura, foram determinadas as espécies dominantes em cada formação: 1 Formação Praial-Graminóide: Remirea maritima, Ipomoea imperati, Sporobolus virginicus e Chamaecyse thymifolia; 2 Formação Praial com Moitas: Schinus terebinthifolius, Eugenia sulcata, Pilosocereus arrabidae e Cereus fernambucensis; 3 Formação de Clusia: Pera glabrata, Eugenia sulcata, Sideroxylon obtusifolium e Scutia arenicola; 4 Formação Mata de Restinga: Maytenus obtusifolia, Pera glabrata, Protium heptaphyllum e Coccoloba alnifolia. A similaridade florística da área estudada com outras restingas nos Estados do Rio de Janeiro e Espírito Santo não ultrapassou 41%, onde a proximidade geográfica não representou aumento da similaridade. Os resultados ressaltam a variação da flora de restinga ao longo de um pequeno trecho do litoral brasileiro.

  9. Botrytis cinerea en plantas cultivadas para flor de corte en Argentina.

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    Eduardo R. Wright

    1996-05-01

    Full Text Available Em levantamentos efetuados nos viveiros e centros de venda em Buenos Aires (Argentina e por consultas recebidas no laboratório de Sanidade Vegetal (LASAVE durante os últimos anos, observaram-se diversos sintomas em plantas ornamentais cultivadas para flor de corte. Sobre as flores eram observadas pequenas manchas, inicialmente translúcidas e depois castanhas, que confluíam e avançavam para o pedúnculo ocupando toda a flor, às vezes estendendo-se até o talo. Quando a infecção ocorria em estado de botão floral, este não se abria e ficava mumificado. Posteriormente à realização de tratos culturais que causavam feridas, era observado um escurecimento dos talos. Todos os órgãos afetados cobriam-se de um mofo cinzento, formado por micélio, conidióforos e conídios do fungo. Esta sintomatologia foi constatada nas seguintes espécies: Anemone coronaria L., Chrysanthemum sp., Dianthus caryophyllus L., Gerbera jamesonü Bolus ex J.D. Hook, Gladiolus sp., Limonium sp., Rosa sp., Strelitzia reginae Banks ex Aiton e Tagetes sp. O objetivo do presente trabalho foi determinar a etiologia da doença utilizando-se técnicas fitopatológicas de rotina. Os resultados dos testes de patogenicidade demonstraram que o agente causal da sintomatologia observada é Botrytis cinerea Pers.: Pers., sem registro na Argentina nas espécies estudadas exceto Dianthus caryophyllus e Rosa sp..

  10. Morfologia da flor e formação do fruto no amendoim cultivado (Arachis hypogaea, L. Flower morphology and fruit development in the cultivated peanut (Arachis hypogaea L.

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    Candida H. T. M. Conagin

    1955-01-01

    Full Text Available O amendoim comum pertence à espécie Arachis hypogxa L. ; outras espécies não apresentam valor econômico algum. As variedades comerciais podem ser reunidas em três grupos - Virgínia, Spanish e Valência - de acôrdo com a distribuição das gemas vegetativas e reprodutivas e também com o número de sementes por fruto. Nêste trabalho é apresentado um estudo da morfologia, duração e fertilização da flor, mostrando que no amendoim não existe a suposta distinção de flôres férteis e estéreis. Também a formação do fruto é descrita, mostrando a interessante característica desta planta, que é ter flôres aéreas e frutos subterrâneos.This work is based mostly on the descriptions given in Smith's paper "Arachis hypogxa L. Aerial flower and Subterranean Fruit" (2 and in the symposium "The Peanut. The unpredictable Legume" (3, and also on some of the author's observations. All cultivated peanut varieties belong to the species Arachis hypogxa L.; other species of the genus are not used for commercial production and may be of interest only for breeding purposes. Commercial peanut varieties can be grouped into one of three types : Virginia, Spanish, and Valencia. This grouping is done according to the distribution of vegetative and reproductive buds on the plant, and to the number of seeds per fruit. Studies were made on flower morphology, its duration and fertilization ; they indicated that all peanut flowers are potentially fertile and cannot, therefore, be classed into fertile and infertile types. A description of how the aerial flowers produce subterranean fruits is given.

  11. Levantamento florístico e fitossociológico em duas áreas de cerrado sensu stricto no Parque Estadual da Serra de Caldas Novas, Goiás

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    Silva Lucivânio Oliveira

    2002-01-01

    Full Text Available A necessidade de se conhecer mais sobre o Bioma Cerrado torna-se cada vez mais urgente, devido à destruição acelerada deste bioma. Este trabalho teve como objetivo realizar um levantamento florístico e fitossociológico em duas áreas de Cerrado sensu stricto, no Parque Estadual da Serra de Caldas Novas, registrando as espécies arbóreas e arbustivas, utilizando o método de Point Centered Quarter. Verificou-se que apesar de algumas diferenças litológicas, latossolo vermelho-escuro na primeira área e vermelho-amarelo na segunda, a similaridade entre elas foi alta, com índices de Jaccard (0,72 e Morisita (0,64. Das 67 espécies pertencentes a 51 gêneros e 29 famílias, 48 foram comuns às duas áreas. Kielmeyera coriacea, Qualea grandiflora, Caryocar brasiliense, Syagrus flexuosa e Ouratea hexasperma tiveram os maiores Índices de Valor de Importância na primeira área e Pouteria ramiflora, Qualea parviflora, Qualea grandiflora, Caryocar brasiliense e Vochysia cinamommea, foram as espécies de maior importância na segunda área. A família Vochysiaceae foi a de maior IVI em ambas as áreas e Leguminosae apresentou o maior número de espécies (15, seguindo Vochysiaceae (7, Apocynaceae (5 e Myrtaceae (4.

  12. Morfologia da flor, fruto e plântula de Victoria amazonica (Poepp. J.C. Sowerby (Nymphaeaceae Morphology of flower, fruit and seedling of Victoria amazonica (Poepp. J.C. Sowerby (Nymphaeaceae

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    Sônia Maciel da Rosa-Osman

    2011-03-01

    Full Text Available Victoria amazonica (Poepp. J.C. Sowerby é uma hidrófita que ocorre nas várzeas de águas brancas e igapós da Bacia Amazônica e na Bacia do rio Paraguai. A morfologia da flor, fruto e plântula/"tirodendro" é objeto do presente trabalho. O material botânico foi coletado em Parintins e Manaus, estado do Amazonas, Brasil. A análise morfológica foi feita em material fresco e fixado em FAA 50. O desenvolvimento das plântulas foi realizado no escuro em frascos com água com teor reduzido de oxigênio. As flores possuem pedicelo longo e são hemicíclicas, diclamídeas, monoclinas e com antese vespertina. Os frutos são carnosos, indeiscentes, com pseudossincarpia. As sementes apresentam arilo que atua na dispersão pela água. As plântulas se desenvolvem em condições de hipoxia e apresentam um cotilédone exposto acicular. O "tirodendro" apresenta eofilos com heterofilia. As flores apresentam caracteres morfológicos básicos da família, a definição do tipo de fruto exige estudo ontogenético e a heterofilia é um caráter típico de plântulas/"tirodendros"de Nymphaeaceae.Victoria amazonica (Poepp. J.C. Sowerby is a hydrophyte that occurs in the white water leas and igapos of the Amazonian and Paraguay Basin. The flower, fruit and seedling/"tirodendro" morphology is the object of the present work. The botanical material was collected at Parintins and Manaus, Amazonian state, Brazil. The morphological analysis was made in both fresh and fixed material. The seedling development was accomplished in flasks with water containing little oxygen and maintained in the darkness. Flowers present long pedicel and they are hemicyclic, dichlamydeous, bisexual with vespertine anthesis. Fruits are fleshy, indehiscent with pseudo-syncarpy. Seeds present aril that acts in the water dispersion. Seedlings grow in hypoxy conditions and they present an acicular and exposed cotyledon. The "tirodendro" stage presents eophylls with heterophylly. Flowers

  13. Alterações na composição florística das algas da Praia de Boa Viagem (Niterói, RJ)

    OpenAIRE

    TAOUIL, ANDRÉ; YONESHIGUE-VALENTIN, YOCIE

    2002-01-01

    A Baía de Guanabara no decorrer da ocupação de suas margens sofreu uma continua degradação, levando-a a grandes modificações em seu entorno e a inúmeros danos ambientais. Além de uma significativa alteração paisagística, ocorreu também uma queda na qualidade de suas águas, devido ao lançamento de grande quantidade de efluentes não tratados (domésticos e industriais). Este trabalho teve como objetivo inventariar a flora algácea da praia de Boa Viagem (Niterói, RJ), compará-la com levantamentos...

  14. Composição florística do componente arbóreo de um trecho de Floresta Atlântica na Área de Proteção Ambiental da Serra da Capoeira Grande, Rio de Janeiro, RJ, Brasil Floristic survey of the tree layer in an area of Atlantic Rainforest in Serra da Capoeira Grande Environmental Protection Area, Rio de Janeiro State, Brazil

    Directory of Open Access Journals (Sweden)

    Gustavo Luna Peixoto

    2004-03-01

    Full Text Available A Área de Proteção Ambiental (APA da Serra da Capoeira Grande (22º59'03"S e 43º38'59"W tem área total de 80ha e é um dos últimos remanescentes florestais com pau-brasil (Caesalpinia echinata Lam. no município do Rio de Janeiro. Além disso, ocorrem na área outras três espécies ameaçadas de extinção: Cariniana ianeirensis R. Knuth, Acosmium lentiscifolium Spreng. e Machaerium incorruptible (Vell. Fr. All. ex Benth. O levantamento fitossociológico foi realizado por meio do método dos quadrantes, tendo sido alocados 200 pontos e tendo-se como critério de inclusão 15cm de circunferência do tronco a 1,30m de altura do solo. A composição florística é o resultado desta amostragem acrescida de coletas feitas durante caminhadas no fragmento, totalizando 29 famílias, 58 gêneros e 69 espécies. As famílias que apresentaram maior número de espécies foram: Leguminosae (13, Myrtaceae (6, Euphorbiaceae (5, Bignoniaceae, Bombacaceae, Celastraceae, Flacourtiaceae, Moraceae, Rubiaceae e Solanaceae (3. Analisando a similaridade florística entre a APA da Serra da Capoeira Grande e outras 18 áreas florestais do Rio de Janeiro, observou-se maior identidade florística entre a área estudada e florestas de baixada localizadas próximas ao mar. Todas as florestas reuniram-se com um baixo nível de similaridade, refletindo a diversidade florística das florestas do Rio de Janeiro.The 80-hectare site (22º59'03"S and 43º38'59"W, is one of the last forest remnants in Rio de Janeiro municipality, where brazilwood (Caesalpinia echinata Lam. occurs naturally. Furthermore, three other endangered species occur in this area: Cariniana ianeirensis R. Knuth, Acosmium lentiscifolium Spreng., and Machaerium incorruptible (Vell. Fr. All. ex Benth. Trees were sampled according to the point-centered-quarter method. The inclusion criteria was PBH >15cm; a total of 200 points were surveyed. The floristic composition was comprised of the sampled

  15. Estádio sucessional e fatores geográficos como determinantes da similaridade florística entre comunidades florestais no Planalto Atlântico, Estado de São Paulo, Brasil

    OpenAIRE

    Durigan,Giselda; Bernacci,Luís Carlos; Franco,Geraldo Antonio Daher Correa; Arbocz,Géza de Faria; Metzger,Jean Paul; Catharino,Eduardo Luís Martins

    2008-01-01

    A análise das relações de similaridade florística entre comunidades geralmente conduz ao estabelecimento de padrões, condicionados por fatores diversos que determinam a ocorrência ou não das espécies em diferentes locais. Em busca de tais padrões, foram analisadas as relações de similaridade florística entre comunidades florestais localizadas na região do Planalto de Ibiúna, estado de São Paulo, Brasil. Incluíram-se na análise 21 fragmentos florestais e seis sítios em uma Reserva Florestal co...

  16. Florística e variação espaço-temporal de macrófitas aquáticas em reservatórios de abastecimento da Bacia do Rio Iguaçu, PR, Brasil

    OpenAIRE

    Silva, Suelen Cristina Alves da

    2013-01-01

    Resumo: Macrófitas aquáticas são estruturadoras do ecosistema proporcionando a ciclagem de nutrientes na coluna d'água, além de promover abrigo à fauna aquática. Contudo, a poluição aquática pode promover a intensa proliferação dessas plantas causando efeitos deletérios ao meio aquático além de encarecer os custos com manutenção de turbinas e grades de segurança em reservatórios. O objetivo do presente trabalho foi realizar um levantamento florístico e estudo ecológico da variação espaço-temp...

  17. Florística da vegetação arbustivo - arbórea colonizadora de uma área degradada por mineração de caulim, em Brás Pires, MG Floristic of shrub - tree vegetation colonizing an area degraded by kaolin mining, in Brás Pires, MG

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    Fernanda Squizzatto de Araújo

    2005-12-01

    Full Text Available Este estudo teve como objetivos analisar a composição florística da vegetação arbustivo-arbórea colonizadora de uma área degradada por mineração de caulim, em Brás Pires, MG, compará-la com outros fragmentos florestais e caracterizar aspectos de auto-ecologia das espécies e o solo da área. O levantamento florístico abrangeu uma área de 0,5 ha, subdividida em 50 parcelas contíguas de 10 m x 10 m. Foram incluídos todos os indivíduos com CAP igual ou superior a 10 cm. A composição florística é o resultado desse levantamento acrescida de coletas fora da área de amostragem, totalizando 64 espécies, distribuídas em 50 gêneros e 30 famílias. As famílias com maior número de espécies foram Leguminosae (11, Annonaceae (5, Lauraceae e Melastomataceae (4, enquanto o gênero mais rico foi Machaerium (3. A análise do substrato, nas condições em que se encontrava, revelou que este não impedia o estabelecimento da vegetação. A síndrome de dispersão preponderante era a zoocórica, destacando-se a importância de indivíduos remanescentes, fragmentos próximos e sua fauna associada. A maior similaridade florística ocorreu com o fragmento em Cruzeiro, SP, estando ambas as áreas em início de sucessão.This study aimed to analyze the floristic composition of shrub-tree vegetation colonizing an area degraded by kaolin mining in Brás Pires, MG, compare it with other forest fragments and characterize ecological aspects of species and soil of the area. The sampled area was 0.5 ha subdivided in 50 grid plots of 10x10 meters each. All individuals included had CAP equal or larger than 10cm. The floristic composition is the result of the sampled area plus species collected outside of it. A total of 64 species was obtained, distributed in 50 genera and 30 families. The families with the greater number of species were Leguminosae (11, Annonaceae (5, Lauraceae e Melastomataceae (4, while the richest genus was Machaerium (3. The soil

  18. Flor Yeast: New Perspectives Beyond Wine Aging

    Science.gov (United States)

    Legras, Jean-Luc; Moreno-Garcia, Jaime; Zara, Severino; Zara, Giacomo; Garcia-Martinez, Teresa; Mauricio, Juan C.; Mannazzu, Ilaria; Coi, Anna L.; Bou Zeidan, Marc; Dequin, Sylvie; Moreno, Juan; Budroni, Marilena

    2016-01-01

    The most important dogma in white-wine production is the preservation of the wine aroma and the limitation of the oxidative action of oxygen. In contrast, the aging of Sherry and Sherry-like wines is an aerobic process that depends on the oxidative activity of flor strains of Saccharomyces cerevisiae. Under depletion of nitrogen and fermentable carbon sources, these yeast produce aggregates of floating cells and form an air–liquid biofilm on the wine surface, which is also known as velum or flor. This behavior is due to genetic and metabolic peculiarities that differentiate flor yeast from other wine yeast. This review will focus first on the most updated data obtained through the analysis of flor yeast with -omic tools. Comparative genomics, proteomics, and metabolomics of flor and wine yeast strains are shedding new light on several features of these special yeast, and in particular, they have revealed the extent of proteome remodeling imposed by the biofilm life-style. Finally, new insights in terms of promotion and inhibition of biofilm formation through small molecules, amino acids, and di/tri-peptides, and novel possibilities for the exploitation of biofilm immobilization within a fungal hyphae framework, will be discussed. PMID:27148192

  19. Análise da composição florística e fitossociológica da floresta nacional do Tapajós com o apoio geográfico de imagens de satélites Analysis of the floristic and phytosociologic composition of Tapajós national forest with geographic support of satellite images

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    Fernando Del Bon Espírito-Santo

    2005-06-01

    Full Text Available O objetivo desse trabalho foi analisar a distribuição da cobertura vegetal de diversas porções da Floresta Nacional (FLONA do Tapajós (FNT, no Pará, através de atributos florísticos e fitossociológicos apoiados por imagens de satélites, em áreas de floresta primária (FP e floresta secundária (FS. Para isso foram amostrados 35 transectos de 10 m ' 250 m em áreas de FP de alto e baixo platô, incluindo também as áreas alteradas por de corte florestal seletivo de madeira e 29 transectos de 10 m ' 100 m em áreas de FS em vários estágios regenerativos. Em cada um desses transectos foram levantadas informações dendrométricas como DAP (Diâmetro à Altura do Peito, altura total (AT e altura comercial (AC, além de localização dos indivíduos arbóreos dentro das amostras. Os diâmetros de inclusão para as áreas de floresta primária e secundária foram de 10 cm e 3 cm, respectivamente. Foram inventariados 7666 indivíduos (6607 árvores ou arbustos e 1059 palmeiras em uma área amostral de 11,65 ha, distribuídos em diferentes regiões da FNT. Foram identificadas em áreas de FP e FS 190 espécies de árvores, arbustos e palmeiras distribuídas entre 153 gêneros e 46 famílias. Nas FP e FS foi encontrado um índice de diversidade de Shannon-Wiener (H' de 4,44 e 4,09 nits.indivíduos-1, respectivamente, indicando uma alta diversidade biológica para essas duas fitofisionomias. Através de análises multivariadas foi possível concluir que existe uma diferença florística e quantitativa na porção norte, centro e sul da FLONA. As áreas de FS apresentaram uma grande heterogeneidade ambiental, dificultando o processo de agrupamento das suas fases sucessionais. Através desse trabalho foi possível concluir que o apoio das imagens ETM+/Landsat e RADARSAT-1 otimizou o processo de amostragem da FNT e possibilitou a análise espacial das regiões com maior diferenciação florística e fitossociológica da Floresta Nacional

  20. Levantamento florístico do componente arbustivo-arbóreo da vegetação ciliar na bacia do rio Taperoá, PB, Brasil Floristic survey of components of shrub-tree riparian vegetation in the Taperoá river basin, Paraíba State, Brasil

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    Alecksandra Vieira de Lacerda

    2005-09-01

    Full Text Available Considerando o papel relevante e o nível de degradação presente nas áreas ciliares, a pesquisa objetivou estudar a composição florística do componente arbustivo-arbóreo da vegetação ciliar em diferentes ambientes hídricos do semi-árido paraibano na bacia do rio Taperoá. O levantamento florístico foi realizado no período de junho/2002 a fevereiro/2003 e abrangeu nove pontos distribuídos ao longo de rios, riachos, lagoa e açude. A definição das atividades apoiou-se em análise de cartas e mapas da vegetação em escala de 1:100.000 e caminhadas aleatórias que permitiram a realização de coleta de material vegetal, utilizado para identificação por meio de consultas a especialistas e de morfologia comparada, usando bibliografia especializada e análise das exsicatas depositadas no herbário Lauro Pires Xavier - JPB (UFPB, João Pessoa, PB. A vegetação arbustivo-arbórea da mata ciliar nos nove pontos amostrados foi representada por 43 espécies, das quais 41 são pertencentes a 19 famílias, e duas espécies permaneceram indeterminadas. As famílias que apresentaram o maior número de espécies foram Mimosaceae (sete, Caesalpiniaceae (cinco e Euphorbiaceae (cinco. Os resultados da análise de agrupamento indicaram que as áreas ciliares apresentaram certa particularização em termos de composição florística, o que se refletiu nos baixos índices de similaridades entre o conjunto de áreas amostradas.Considering the relevant role and the current level of degradation of riparian areas, this work aimed to study the floristic composition of shrub-tree riparian vegetation at different hydric environments in the Taperoá river basin, in the semi-arid region of the Paraíba State, Northeast Brazil. The survey was performed from June 2002 to February 2003. Nine sampling sites were distributed along rivers and streams, and around lagoon, and dam. The definition of activities was based on the analysis of charts and vegetation maps

  1. Um país à flor da pele: a relação dos brasileiros com o futebol na cobertura da Copa do Mundo pelo jornal The Guardian

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    Maria Carolina Vieira

    2016-09-01

    Full Text Available O jornalismo internacional tem o papel de reportar sobre outros países e culturas, contribuindo, assim, para a construção de um olhar estrangeiro sobre diversos aspectos nacionais. A Copa do Mundo 2014, por sua vez, foi um momento abundante na formação de imagens sobre o país-sede e seus habitantes, já que os holofotes da mídia estavam voltados para o Brasil. Diante destas considerações, este trabalho foca no estudo das representações sobre a relação dos brasileiros com o futebol no The Guardian, tema que se destacou na cobertura do megaevento esportivo no jornal inglês. Utilizando a Análise de Conteúdo, verificou-se que a emotividade e o futebol como algo que significa mais do que um esporte são fatores-chave para o entendimento estrangeiro da relação Brasil x futebol. Esta visão passional, no entanto, não se estende a outros assuntos abordados no período, sugerindo que a postura editorial dos veículos pode influenciar as representações midiáticas tanto quanto seus históricos ou os próprios acontecimentos.

  2. Composição florística e a conservação de floresta secundárias na serra da Cantareira, São Paulo, Brasil. Floristic composition and conservation of old secondary Forest in the serra Cantareira in São Paulo, South-Eastern Brazil.

    Directory of Open Access Journals (Sweden)

    Frederico Alexandre Roccia Dal Pozzo ARZOLLA

    2011-06-01

    Full Text Available Florestas secundárias estão seriamente ameaçadas pela expansão urbana na região metropolitana. Alguns remanescentes são protegidos, principalmente em parques estaduais e municipais, mas a maioria dessas florestas está sob risco de supressão pela contínua expansão de áreas urbanas. O objetivo deste trabalho foi caracterizar a composição florística do componente arbóreo de trecho de floresta, em estágio médio a avançado de regeneração no Parque Estadual da Cantareira, São Paulo (SP. Foram realizadas caminhadas nos traçados antigo e novo da Linha de Transmissão Guarulhos–Anhanguera, num total aproximado de 11 km de extensão. A amostragem foi realizada no período de 2006 a 2010. No levantamento florístico, foram identificadas 179 espécies, pertencentes a 54 famílias e 127 gêneros. As famílias com maior riqueza de espécies foram Fabaceae (19 espécies, Myrtaceae (18, Lauraceae (16 e Rubiaceae (15 e os gêneros mais ricos, Ocotea e Myrcia (6, Eugenia (5 e Maytenus, Mollinedia e Nectandra com quatro espécies cada. Foram registradas dez espécies consideradas ameaçadas de extinção, sendo quatro espécies na lista de São Paulo e seis na lista da IUCN. Uma delas, Mollinedia oligotricha, é considerada presumivelmente extinta. A similaridade florística encontrada com outros remanescentes florestais da Região Metropolitana de São Paulo e arredores variou entre 11% a 38%. Florestas secundárias apresentam uma considerável riqueza de espécies, incluindo espécies ameaçadas de extinção. Foram discutidas as pressões incidentes sobre esses remanescentes florestais, bem como possíveis estratégias para a sua conservação.Secondary forests are seriously threatened by urban expansion in the metropolitan region of São Paulo. Some remnants are protected, mainly in state or municipal parks, but most of these forests are in immanent danger of being destroyed by the continual expansion of urban areas. The aim of this

  3. Similaridade florística das florestas superomontanas no domínio Atlântico, Brasil

    OpenAIRE

    Amanda Koche Marcon; Ana Carolina da Silva; Pedro Higuchi; Francieli de Fátima Missio; Tiago de Souza Ferreira; Bruna Salami; Angelica Dalla Rosa; Marco Antonio Bento; Fernando Buzzi Júnior

    2014-01-01

    Este estudo teve como objetivos avaliar a similaridade florística do componente arbóreo de 39 remanescentes de florestas superomontanas no domínio atlântico, Brasil, e analisar a influência de variáveis geográficas e climáticas sobre os padrões observados. Foi utilizada uma matriz binária de presença e ausência das espécies arbóreas compiladas dos 39 levantamentos florísticos e fitossociológicos. Para conhecer a relação da composição florística das áreas com variáveis ambientais e espaciais, ...

  4. Composição florística, espectro biológico e fitofisionomia da vegetação de muçununga nos municípios de Caravelas e Mucuri, Bahia Floristic composition, biological spectrum and phytophysiognomy of muçununga vegetation at Caravelas and Mucuri municipalities, Bahia state, Brazil

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    João Augusto Alves Meira Neto

    2005-02-01

    Full Text Available A pouco conhecida vegetação de muçununga ocorre em Florestas Ombrófilas Densas de Terras Baixas no norte do Espírito Santo e Sul da Bahia, em locais de solo arenoso, úmido e fofo. Este trabalho teve como objetivo realizar estudos florísticos e fitofisionômicos para uma avaliação de como interferências antrópicas influenciaram a composição e a estrutura das muçunungas de Caravelas (17º41'13''S e 39º28'24''W e Mucuri (18º10'29''S e 39º53'25''W, no Estado da Bahia. Foram realizadas incursões na vegetação para coletas botânicas e construção do espectro biológico. Foram feitos perfis em quatro diferentes estratos, em ambas as muçunungas. Na muçununga de Caravelas foram relacionadas 67 espécies de 32 famílias e na de Mucuri, 53 espécies de 31 famílias. Na listagem florística ficou evidenciada a maior riqueza da muçununga de Caravelas. Nos perfis é possível perceber maior equabilidade na distribuição dos indivíduos entre as espécies da muçununga de Caravelas que entre as espécies de Mucuri. Os impactos originários da atividade humana favoreceram as formas de vida hemicriptofítica e as lianas na muçununga de Mucuri. As espécies Baccharis trimera, Blechnum serrulatum, Imperata brasiliensis e Pteridium aquilinum são indicadoras dos impactos de passagem de fogo e pastejo bovino. Os impactos antrópicos nas muçunungas foram os principais responsáveis pela diminuição da biodiversidade nesse tipo de vegetação.Little is known about muçununga vegetation, which occurs surrounded by Tropical Rain Forests in northern Espirito Santo State and southern Bahia State, in sites with sandy and wet soils. This work had the objective of studying floristic and phytophysiognomic aspects in order to evaluate how human activity influenced the structure and composition of the muçununga vegetation of Caravelas (17o41'13''S and 39o28'24''W and Mucuri (18o10'29''S and 39o53'25''W. This work was carried out trough paths in mu

  5. ITS-rDNA phylogeny of Colletotrichum spp. causal agent of apple Glomerella leaf spot Filogenia por ITS-rDNA de Colletotrichum spp., agente causal da mancha foliar da Gala em macieira

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    Diorvania Ribeiro Giaretta

    2010-04-01

    Full Text Available Several diseases have affected apple production, among them there is Glomerella leaf spot (GLS caused by Colletotrichum spp. The first report of this disease in apple was in plants nearby citrus orchards in São Paulo State, Brazil. The origin of this disease is still not clear, and studies based on the molecular phylogeny could relate the organisms evolutionarily and characterize possible mechanisms of divergent evolution. The amplification of 5.8S-ITS (Internal Transcribed Spacer of rDNA of 51 pathogenic Colletotrichum spp. isolates from apples, pineapple guava and citrus produced one fragment of approximately 600 bases pairs (bp for all the isolates analyzed. The amplified fragments were cleaved with restriction enzymes, and fragments from 90 to 500bp were obtained. The sequencing of this region allowed the generation of a phylogenetic tree, regardless of their hosts, and 5 isolated groups were obtained. From the "in silico" comparison, it was possible to verify a variation from 93 to 100% of similarity between the sequences studied and the Genbank data base. The causal agent of GLS is nearly related (clustered to isolates of pineapple guava and to the citrus isolates used as control.A produção de maçã vem sendo comprometida pela ocorrência de muitas doenças, entre as quais se destaca a Mancha Foliar de Glomerella (MFG, causada por Colletotrichum spp. O primeiro relato dessa doença em maçã foi registrado em plantas próximas a pomares de citrus no Estado de São Paulo, Brasil. A origem da MFG ainda não está bem clara, e estudos baseados na filogenia permitirão relacionar o organismo evolutivamente, possibilitando caracterizar possíveis mecanismos divergentes de evolução. A amplificação da região 5.8S-ITS (espaçador interno transcrito do rDNA de 51 isolados de Colletotrichum patogênicos em de maçã, goiabeira serrana e citrus produziu um fragmento de aproximadamente 600 pares de bases (pb para todos os isolados analisados

  6. Florística e fitossociologia da vegetação de um campo sujeito à arenização no sudoeste do Estado do Rio Grande do Sul, Brasil Floristics and phytosociology of grassland vegetation subject to sandy desertification in southwestern Rio Grande do Sul State, Brazil

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    Elisete Maria de Freitas

    2009-06-01

    Full Text Available Extensas áreas de campo nativo do sudoeste do Rio Grande do Sul são suscetíveis ao processo de arenização, que ocorre em áreas de fragilidade pedológica, tendo influência de interferência antrópica e fatores abióticos. Com o objetivo de testar a variação da cobertura vegetal e a dinâmica da arenização no tempo e conforme a influência da distância da encosta, foi desenvolvido um estudo florístico e fitossociológico em áreas de campo nativo sob pastejo. Duas subáreas, diferentes quanto ao processo da arenização, foram selecionadas no município de São Francisco de Assis, RS. O levantamento florístico apontou a ocorrência de 102 espécies, distribuídas em 25 famílias. No estudo fitossociológico, 35 quadros permanentes de 0,25 m² em cada subárea foram dispostos em diferentes distâncias da encosta do morro. Foram registradas as coberturas das espécies vegetais, do mantilho e do solo exposto em três períodos. Dados sobre riqueza e diversidade de espécies e formas de vida foram avaliados por análise de variância, via testes de aleatorização, considerando o fator temporal e o espacial (distância da encosta. Houve maior redução da diversidade específica e da cobertura vegetal na subárea 1 (com menor cobertura vegetal conforme a variação temporal. Na subárea 2 (com maior cobertura vegetal, o aumento do solo exposto e a conseqüente redução da cobertura vegetal tiveram maior influência da distância da encosta. A alteração da cobertura vegetal e a expansão da arenização observadas ao longo do tempo são resultado da influência conjunta da dinâmica pluviométrica, do tipo solo, da presença de encostas dos relevos tabulares com pouca vegetação e da contínua pressão de pastejo.Extensive areas of native grassland in southwestern Rio Grande do Sul are susceptible to sandy desertification, which occurs in pedologically fragile areas influenced by anthropic interference and abiotic factors. A

  7. Dinâmica inicial da composição florística de uma área restaurada na região do Pontal do Paranapanema, São Paulo, Brasil Initial dynamics of floristic composition in a restoresd area in the region of Pontal do Paranapanema, São Paulo state, Brazil

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    Elisangela Ronconi Rodrigues

    2010-10-01

    Full Text Available O Pontal do Paranapanema, extremo oeste do Estado de São Paulo, é marcado pela recente devastação florestal, e ações visando à recuperação de áreas onde outrora havia cobertura florestal tornam-se indispensáveis para a conservação da biodiversidade na região, principalmente quando se trata de áreas de Reserva Legal ou Preservação Permanente. Diante do exposto, esta pesquisa teve como objetivo analisar a dinâmica inicial da composição florística em uma área de Reserva Legal restaurada. O trabalho foi realizado no assentamento Nova Esperança, Município de Euclides da Cunha Paulista, em uma área de 26,75 ha. O levantamento das espécies foi realizado pelo método de parcelas (16 parcelas de 20 x 30 m em duas fases distintas do plantio, e as análises foram feitas utilizando-se o software Fitopac. Os resultados evidenciaram diminuição da biodiversidade pela alta mortalidade de espécies, levando à conclusão de que em projetos de restauração as intervenções são necessárias para a manutenção do plantio mesmo em sua fase inicial.The Pontal do Paranapanema Region is located in the western range of the State of São Paulo is characterized by recent forest destruction and actions are needed for forest restorations and conservation of biodiversity in the region, principally when if treated of areas of Legal Reserve or Permanent Preservation. Before of the exposed this research had it objective analyze the dynamics initial from floristic composition an area of Legal Reserve restored. This work was realized into the Nova Esperança settlement, city of Euclides da Cunha Paulista, an area of 26,75 ha. The lifting from the species was realized at method of parcels (16 parcels of 20 x 30 m into two phases differentiate of the plantation, and the analisys have been using Fitopac software.The results they show only one decrease from biodiversity by high mortality of species, taking the conclusive what projects of restoration

  8. Levantamento florístico das macroalgas da baía de Sepetiba e adjacências, RJ: ponto de partida para o Programa GloBallast no Brasil Floristic survey of the macroalgae from Sepetiba bay and surrounding area, Rio de Janeiro State: starting point for the GloBallast Programme in Brazil

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    Maria Teresa Menezes de Széchy

    2005-09-01

    Full Text Available O Porto de Sepetiba, Estado do Rio de Janeiro, foi escolhido, no Brasil, como área-piloto do projeto "Remoção de barreiras para a implementação efetiva do controle de água de lastro e medidas de gestão em países em desenvolvimento" (Programa GloBallast. Para possibilitar comparações, os seis países participantes do Programa GloBallast foram orientados a adotar a mesma metodologia para o levantamento preliminar da biota das áreas-pilotos valorizando a identificação em nível de espécie. O presente estudo teve como objetivo aplicar metodologia estabelecida pelo Centro para Pesquisa sobre Espécies Marinhas Introduzidas, da Austrália (Procedimento CRIMP, com algumas adaptações, no levantamento florístico das macroalgas de substratos consolidados naturais da área-piloto do Porto de Sepetiba. Coletas de macroalgas foram realizadas em novembro/2001, em nove locais da baía de Sepetiba e adjacências, desde a franja da região sublitorânea até cerca de -4 m de profundidade. Em cada local, seis quadrados de 0,1 m² de área foram raspados. O material foi depositado no Herbário do Instituto de Pesquisas Jardim Botânico do Rio de Janeiro (RB. Das 96 espécies identificadas (20 Chlorophyta, 16 Phaeophyta, 60 Rhodophyta, 12 não haviam sido citadas anteriormente para a área de estudo. Cladophora pellucidoidea C. Hoek, Coelothrix irregularis (Harv. Boergesen e Acrochaetium savianum (Menegh. Nägeli são ocorrências novas para o Estado. Não há indícios de que as novas ocorrências equivalem a espécies recentemente introduzidas por meio das atividades portuárias. O procedimento metodológico adotado mostrou-se eficiente, resultando em listagem de espécies comparável às de levantamentos florísticos com maior esforço amostral e complementando os dados pretéritos existentes para a baía de Sepetiba e adjacências. No entanto, ressalta-se a importância de uma reavaliação das escalas temporal e espacial da estratégia de

  9. Quando morre a flor do sertão: figuração da morte em “Buriti” de João Guimarães Rosa

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    Sarah Maria Forte Diogo

    2008-12-01

    Full Text Available Este artigo tem por objetivo estudar de que modo é figurada a morte da personagem Maria Behú, de “Buriti”, Noites do sertão (1956, de João Guimarães Rosa e os símbolos que a ela se agregam. Para tanto, investigamos as focalizações narrativas que incidem sobre Behú, construindo sua imagem como beata, assexuada, atuante na esfera da metafísica, sendo a sua morte o início da intensa vivência da sexualidade pelos demais personagens. “Buriti” narra a estória dos habitantes da fazenda Buriti Bom e daqueles que por lá transitam e as mudanças que ocasionam na vida uns dos outros. Behú é a personagem que mais contrasta com o ambiente, pois dele difere por não apresentar marcas de erotismo ou vida plena. Behú funciona na novela como guardiã da tradição e da cultura, seus usos e seus costumes, estilizados pela linguagem roseana.Palavras-chave: João Guimarães Rosa; Cultura; Linguagem; Morte; Tradição.

  10. Composição florística da vegetação arbórea de um trecho de floresta estacional semidecídua em Viçosa, Minas Gerais, e espécies de maior ocorrência na região Floristic composition of trees in a seasonal semidecious forest in Viçosa, Minas Gerais, and species of greater ocurrence in the region

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    Walnir Gomes Ferreira Júnior

    2007-12-01

    Full Text Available É grande a demanda por estudos ecológicos em florestas que possam embasar trabalhos de recuperação, conservação da biodiversidade e apoio à legislação ambiental. Entre esses estudos, primordialmente está o levantamento da flora. Nesse sentido, este trabalho teve como objetivo determinar a composição florística de um trecho da Reserva da Biologia, em Viçosa, MG, em regeneração natural há 80 anos, bem como realizar uma análise comparativa com outros trabalhos conduzidos na região, fornecendo, assim, informações que poderão embasar estudos sobre recuperação e conservação da biodiversidade dos fragmentos de Floresta Estacional Semidecidual. Os dados florísticos foram obtidos mediante a amostragem fitossociológica em 1 ha, pelo método de parcelas contíguas, em que todos os indivíduos arbóreos com circunferência de tronco >15 cm a 1,30 m do solo foram amostrados. Registraram-se 130 espécies, distribuídas em 94 gêneros, pertencentes a 38 famílias botânicas. A análise desses dados conjuntamente com de outros levantamentos realizados em trechos distintos da Reserva da Biologia, no campus da UFV, denota a marcante influência de variáveis ambientais locais (topografia, declividade, face de exposição solar e disponibilidade hídrica na distribuição da riqueza florística desse fragmento. Casearia decandra, Guapira opposita, Apuleia leiocarpa, Dalbergia nigra, Jacaranda macratha, Matayba elaeagnoides, Piptadenia gonoacantha, Bathysa nicholsonii, Carpotroche brasiliensis, Luehea grandiflora, Mabea fistulifera, Ocotea odorifera, Sorocea bonplandii e Zanthoxylum rhoifolium foram as espécies de maior ocorrência nos fragmentos estudados na região de Viçosa e adjacências, apresentando potencial para uso na recuperação florestal de áreas degradadas.There is a great demand for ecological studies on forests focusing on biodiversity conservation and establishment of environmental laws. The major need, however, is

  11. Composição florística e estrutura de um trecho de floresta ombrófila densa atlântica com uso pretérito de produção de banana, no parque estadual da Pedra Branca, Rio de Janeiro, RJ

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    Alexandro Solórzano

    2012-06-01

    Full Text Available Este estudo teve como objetivos caracterizar florística e estruturalmente um trecho de Floresta Ombrófila Densa Submontana urbana e avaliar os fatores que contribuíram para a regeneração, a partir do último uso do solo para produção de banana, há 50 anos. Para a amostragem da área foram implantadas 25 parcelas de 100 m², totalizando 0,25 ha. O critério de inclusão adotado foi diâmetro à altura do peito (DAP > 5 cm. Foram amostrados 311 indivíduos de 92 espécies, 67 gêneros e 31 famílias. A área basal total foi de 34,18 m²/ha, enquanto a densidade, de 1.244 ind./ha. As espécies mais importantes na comunidade, representando 42% do valor de importância (VI da área, foram: Aiouea saligna Meisn., Tachigali paratyensis (Vell. H.C. Lima, Ficus insipida Willd., Bathysa gymonocarpa K. Schum, Chrysophyllum flexuosum Mart., Piptadenia gonoacantha (Mart. J.F. Macbr., Piper rivinoides Kunth., Hyeronima alchorneoides Allemão, Miconia cinnamomifolia (DC. Naudin e Guarea guidonia (L. Sleumer. O elevado valor do Índice de diversidade de Shannon (H'= 4,13 nats/ind., bem como o de equabilidade (J = 0,91, compara-se aos valores referenciados para florestas conservadas e inventariadas no Sudeste brasileiro. A floresta amostrada encontra-se em processo de regeneração e representa um estágio intermediário de sucessão. O cultivo da banana, após seu abandono, permitiu a entrada de espécies com estratégias de estabelecimento e propagação em condições de pouca luminosidade. A presença de uma árvore remanescente, do gênero Ficus, está relacionada a uma crença popular que acabou influenciando a estrutura da vegetação. Dessa forma, as espécies amostradas neste estudo refletiram o uso do solo passado e a cultura local.

  12. Florística e estrutura da comunidade arbórea de um fragmento florestal em Luminárias, MG Floristic composition and structure of the tree layer of a forest fragment in Luminárias Municipality, Minas Gerais State

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    Luciene Alves Rodrigues

    2003-03-01

    Full Text Available O objetivo deste trabalho foi analisar a composição florística e estrutural da comunidade arbórea de uma floresta em Luminárias, MG. O local de estudo é conhecido como Mata do Galego, possui cerca de 77 ha e está localizado a 21°29'S e 44°55'W, às margens do rio Ingaí. A amostragem florística foi realizada em parcelas e também em caminhadas pela floresta. Todo o material coletado foi identificado e incorporado ao Herbário ESAL, da Universidade Federal de Lavras. O levantamento estrutural foi realizado por meio de amostragem sistemática, em 32 parcelas de 20 × 20m, distribuídas em três transeções, da margem do rio até a borda da mata. Nas parcelas, foram amostrados todos os indivíduos arbóreos, vivos, com circunferência à altura do peito (CAP ≥ 15,5 cm. As variáveis químicas e físicas do solo foram obtidas das análises de amostras superficiais de solo (0-20 cm de cada parcela. No levantamento florístico foram amostradas 201 espécies, 129 gêneros e 57 famílias. As famílias com maior riqueza foram Myrtaceae, Lauraceae, Fabaceae Faboideae, Rubiaceae, Euphorbiaceae e Fabaceae Mimosoideae. No levantamento estrutural foram amostrados 2343 indivíduos de 159 espécies, 104 gêneros e 50 famílias. As espécies mais abundantes foram Casearia sylvestris, Lithraea molleoides, Machaerium stipitatum, Faramea cyanea, Diospyros inconstans e Copaifera langsdorffii. A Mata do Galego apresentou alta diversidade de espécies (H' = 4,23 nat/indivíduo e alta equabilidade (J' = 0,83. A alta diversidade de espécies pode estar relacionada à influência de formações vegetais próximas e aos diferentes microhabitats proporcionados pela topografia, variações na fertilidade e umidade do solo.The aim of this study was to analyze the floristic composition and structure of the tree layer of a forest fragment in the municipality of Luminárias, Minas Gerais State, southeastern Brazil. The forest fragment is locally known as Mata do

  13. Relações florísticas, estruturais e ecológicas entre as florestas do topo da Serra do Mar e as florestas de restinga no Estado de São Paulo

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    Joao Carlos Miguel Tomaz Micheletti Neto

    2007-01-01

    As comunidades florestais periféricas às florestas que recobrem o sopé e as médias encostas da Serra do Mar apresentam uma convergência de fisionomias e aspectos xeromórficos, sustentada por floras que estão relacionadas quanto às suas origens. Como estas semelhanças podem indicar condições ecológicas similares, o trabalho investigou qualitativa e quantitativamente se as semelhanças fisionômicas, entre a Floresta do Topo dos Morros da Serra do Mar e a Floresta Seca de Restinga no Estado de Sã...

  14. Composição florística das formações vegetais sobre uma turfeira topotrófica da planície costeira do Rio Grande do Sul, Brasil

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    Costa César S. B.

    2003-01-01

    Full Text Available Turfeiras topotróficas caracterizam-se como corpos de águas rasas, permanente ou periodicamente alagados por água do lençol freático, percolada através do solo inorgânico das terras altas adjacentes à depressão central da turfeira. Possuem solos orgânicos e a cobertura vegetal é dominanda por fanerógamas aquáticas emergentes. Este estudo visou o levantamento da diversidade específica e caracterização das principais formações vegetais ao longo de duas transecções de 200m em uma turfeira topotrófica na localidade de Domingos Petrolini (Rio Grande, RS. Em março/1998, o total de 48 espécies vegetais (30 famílias foram encontradas nas 40 parcelas de 5m × 2m observadas nas duas transecções efetuadas. Cerca de 56% das espécies eram plantas aquáticas herbáceas (submersas, flutuantes ou emergentes e apenas 10% arbustos ou árvores. Sete espécies dominaram a cobertura vegetal (Eupatorium tremulum, Eryngium pandanifolium, Blechnum brasiliense, Rhynchospora sp., Xyris jupicai, Utricularia gibba e Cladium jamaicense. Quatro formações vegetais tipicamente distribuídas em relação à topografia e à distância do lençol freático foram caracterizadas: (1 banhados do capim-navalha Cladium jamaicense, drenados apenas no verão, ocupam a depressão central da turfeira (DCT; (2 planos médios de Gravatás/Caraguatás (Eryngium pandanifolium associados a samambaia Blechnum brasiliense (+0,5 a +1,5m da DCT; (3 bosques marginais de arbustos palustres (+1 a +3m da DCT são dominados por Eupatorium tremulum; e (4 campos de turfa recobertos por ciperáceas de pequeno porte, gramas boiadeiras e botões-de-ouro (Xyris jupicai ocupam a borda do afloramento da turfa (+3 a +4m da DCT.

  15. Florística em um hectare de cerrado stricto sensu na ARIE - cerrado Pé-de-Gigante, Santa Rita do Passa Quatro, SP

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    Weiser, Veridiana de Lara; Godoy, Silvana Aparecida Pires de

    2001-01-01

    Foi realizado um levantamento florístico em um ha de cerrado stricto sensu, na parte norte da ARIE - Cerrado Pé-de-Gigante, Santa Rita do Passa Quatro, São Paulo. Foram coletados 428 espécimes em fase reprodutiva, em vinte e cinco excursões de coleta, durante o período de novembro de 1996 a abril de 1998. A listagem florística obtida apresenta 141 espécies, distribuídas em 109 gêneros e 49 famílias. As famílias mais representativas foram: Leguminosae, Asteraceae, Malpighiaceae e Myrtaceae. A ...

  16. Florística e estrutura da comunidade arbórea de um remanescente de Floresta Estacional Decidual de encosta, Monte Alegre, GO, Brasil Floristic and structure of a seasonal deciduous forest fragment, Monte Alegre, GO, Brazil

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    André R. Terra Nascimento

    2004-09-01

    Full Text Available O presente estudo teve como objetivo descrever a composição de espécies arbóreas e a estrutura de um fragmento de Floresta Estacional Decidual, na região Nordeste de Goiás, Brasil. Foram levantadas 25 unidades amostrais quadradas de 20x20m, totalizando uma amostra de um hectare, sendo incluídos na amostragem todos os indivíduos com diâmetros iguais ou superiores a 5cm. Foram amostrados 663 indivíduos pertencentes a 52 espécies arbóreas, destacando-se pela densidade as espécies Combretum duarteanum Camb., Casearia rupestris Eichl., Myracrodruon urundeuva Fr. Allem., Machaerium acutifolium Vog. e Tabebuia impetiginosa (Mart. ex DC. Standl. Foram encontradas 21 famílias botânicas, com maior representatividade da família Leguminosae (17 espécies e das famílias Bignoniaceae (4 espécies, Anacardiaceae (3 espécies e Bombacaceae (3 espécies. A vegetação estudada apresentou dossel descontínuo e distribuição diamétrica desequilibrada, com valores do quociente de Liocourt "q" variando de q1= 0,66 a q6 = 0,14. Estes remanescentes florestais desempenham papel importante na manutenção da diversidade biológica e possuem espécies arbóreas madeiráveis de importância econômica, que se tornaram raras em outros locais da região Nordeste de Goiás.The objective of this study was to describe the floristic composition and the structure of the tree layer of a fragment of a seasonal deciduous forest in northeastern Goiás state, Brazil. A sample of 25 (20x20 plots was assessed totaling one hectare. All individuals for 5cm dbh were included in the survey. A total of 663 trees in 52 arboreal species was found; the most abundant species were Combretum duarteanum Camb., Casearia rupestris Eichl., Myracrodruon urundeuva Fr. Allem., Machaerium acutifolium Vog. and Tabebuia impetiginosa (Mart. ex DC. Standl. There were 21 families with a higher proportion of Leguminosae (17 species Bignoniaceae (4 species, Anacardiaceae (3 species and

  17. Composição florística e fitossociologia de espécies arbóreas do Parque Fenológico da Embrapa Amazônia Ocidental Floristic composition and phytosociology of tree species in the Phenological Site of the Embrapa Western Amazonia

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    Kátia Emídio da Silva

    2008-01-01

    Full Text Available Este trabalho objetiva avaliar a composição florística e a fitossociologia de espécies arbóreas do parque fenológico da Embrapa Amazônia Ocidental no Distrito Agropecuário da Suframa (DAS, Manaus-AM, a fim de subsidiar seleções futuras de árvores matrizes visando estudos fenológicos e a implantação de áreas de coleta de sementes. Foram alocadas aleatoriamente 20 parcelas de 10m x 50 m ao longo de um transecto, amostrando-se todos os indivíduos com diâmetro a 1,30 m do solo, (DAP ≥ 20,0 cm. Foram registrados 240 indivíduos, distribuídos em 100 espécies, 70 gêneros e 29 famílias. As famílias de maior importância ecológica são, em ordem decrescente, Lecythidaceae, Sapotaceae, Mimosaceae, Caesalpiniaceae, Chrysobalanaceae, Fabaceae, Humiriaceae, Moraceae, Vochysiaceae e Apocynaceae. Essas famílias contribuem com 67% da riqueza local de espécies e com 75,8% do número de indivíduos, sugerindo que a diversidade vegetal da área está concentrada em poucas famílias. A família Lecythidaceae possui os maiores valores de dap e número de indivíduos, sendo Sapotaceae a que possui a maior riqueza de espécies na área. As espécies mais importantes, segundo o Índice de Valor de Importância-IVI, são Eschweilera coriacea (DC S.A. Mori; Qualea paraensis Ducke; Vantanea macrocarpa Ducke; Eschweilera atropetiolataThis research was carried out to study the floristic composition and phytosociology of tree species in the phenological site of Embrapa Western Amazonia, Suframa Agropecuary District-SAD, Manaus-AM, aiming to help future selection of seed trees, for the establishment of seed collecting areas. Twenty plots of 10m x 50m were studied, along a topographic sequence, where trees with a diameter at breast height (dbh ≥ 20,0cm were inventoried. A total of 240 trees belonging to 29 families, in 70 genera with 100 species were identified. The most important families, in a decreasing order, were: Lecythidaceae, Sapotaceae

  18. Morphology and anatomy of the flower of Guarea kunthiana A. Juss. and Guarea macrophylla Vahl. (Meliaceae Morfo-anatomia da flor de Guarea kunthiana A. Juss. e de Guarea macrophylla Vahl. (Meliaceae

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    Luiz Antonio Souza

    2002-05-01

    Full Text Available Guarea kunthiana A. Juss. and G. macrophylla Vahl. belong to Meliaceae, an arboreal family that occurs in forest fragments in the Northwest of Paraná, Brazil. The flowering time for G. kunthiana is from November to December and for G. macrophylla is from September to November. Flowers of the species are unisexual and they present similar structure. The male flowers present pistillode and anthers with epidermis, endothecium, two median layers and binucleate secretory tapetum. The female flowers present antherode and pistil, whose stigma has secretory lateral portion, the style is solid and the ovary presents parenchymatous mesophyll and meristematic inner epidermis; the ovules are hemianatropous, bitegmic and crassinucelate. The flowers are nectar-secreting.Guarea kunthiana A. Juss. e G. macrophylla Vahl. são espécies pertencentes à família Meliaceae, de hábito arbóreo que ocorrem em remanescentes florestais da região noroeste do Estado do Paraná, Brasil. A primeira floresce de novembro a dezembro e a segunda, de setembro a novembro. As flores das espécies são diclinas e apresentam semelhança estrutural. As flores masculinas têm pistilódio e anteras com epiderme, endotécio, duas camadas médias e tapete secretor com células binucleadas. As femininas apresentam anteródio e pistilo, cujo estigma tem porção secretora lateral; o estilete é sólido; o ovário apresenta mesofilo parenquimático e epiderme interna meristemática; os óvulos são hemianátropos, bitegumentados e crassinucelados. As flores são nectaríferas.

  19. E uma rosa se abre: a guerra e a flor na poesia de Drummond

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    Valéria Daiane Soares Rodrigues

    2013-08-01

    Full Text Available Carlos Drummond de Andrade, em A Rosa do Povo (1945 articula, por meio da palavra e da criação de um “eu” lírico habitante de um mundo em guerra, a construção de uma imagem, imbuída de teor histórico, do Brasil dos anos finais da 2ª guerra mundial. Os versos traduzem a experiência do Drummond gauche, angustiado pelos problemas do seu tempo, em que a individualidade advinda da fragmentação do homem moderno é marca do conflito entre o “eu” lírico e o mundo. O poeta descreve de forma melancólica a degeneração das coisas e dos homens, em meio à consciência paralisante e a falta de perspectivas. A força que emerge do símbolo da rosa respalda o acento poético do Itabirano: a destruição dos valores provocados pela morte e pelo derramar de sangue contrasta com o brotar da flor no asfalto.  Do chão forrado de cadáveres, emerge uma rosa, numa representação da resistência humana.

  20. Análise florística das pteridófitas do Parque Nacional da Restinga de Jurubatiba, Rio de Janeiro, Brasil Floristic analysis of the pteridophytes of the Restinga de Jurubatiba National Park, Rio de Janeiro, Brazil

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    Marcelo Guerra Santos

    2004-06-01

    Full Text Available O Parque Nacional da Restinga de Jurubatiba, localizado no norte do Estado do Rio de Janeiro, abrange os municípios de Macaé, Carapebus e Quissamã. Foram registradas para a área de estudo 12 famílias com 21 gêneros e 32 espécies. As famílias encontradas foram Blechnaceae, Cyatheaceae, Davalliaceae, Dennstaedtiaceae, Dryopteridaceae, Gleicheniaceae, Lycopodiaceae, Polypodiaceae, Pteridaceae, Salviniaceae, Schizaeaceae e Thelypteridaceae. Dessas, as mais representativas em número de espécies foram Polypodiaceae (5 spp. e Pteridaceae (5 spp.. Os gêneros com maior número de espécies foram Nephrolepis, Polypodium e Thelypteris. Das 32 espécies registradas, 23 são ervas terrestres, três são ervas epífitas, três ervas aquáticas, duas arborescentes e uma erva hemiepífita. A maior riqueza de espécies e famílias foi registrada para a formação de mata periodicamente inundada e a menor, para a formação arbustiva fechada de pós-praia. Há baixa similaridade entre a flora pteridofítica de diferentes áreas de restingas analisadas e entre as restingas e a mata atlântica. Blechnum serrulatum e Polypodium triseriale são espécies de ocorrência comum em áreas de restingas. Das 32 espécies inventariadas, 17 possuem usos atribuídos (medicinais, ornamentais e comestíveis.The Restinga de Jurubatiba National Park is located on the Northern coast of Rio de Janeiro State (municipalities of Macaé, Carapebus and Quissamã. There are 12 families, 21 genera and 32 species, with the following families present: Blechnaceae, Cyatheaceae, Davalliaceae, Dennstaedtiaceae, Dryopteridaceae, Gleicheniaceae, Lycopodiaceae, Polypodiaceae, Pteridaceae, Salviniaceae, Schizaeaceae and Thelypteridaceae. The most species-rich families are Pteridaceae (5 spp. and Polypodiaceae (5 spp.. Nephrolepis, Polypodium and Thelypteris were the richest genera. Of the 32 species recorded for the area, 23 are terrestrial herbs, three are epiphytes, three are aquatics

  1. Composição florística e estrutura do componente arbóreo de uma Floresta Paludosa na planície costeira da bacia do rio Itaguaré, Bertioga, SP, Brasil. Floristic composition andstructure of an arboreal component of the Paludal Forest in the coastal plain of the Itaguaré river basin, Bertioga (São Paulo state, Brazil

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    Celia Regina de Gouveia SOUZA

    2012-06-01

    Full Text Available As Florestas Paludosas costeiras ou “caxetais” ocorrem no Domínio Atlântico, em geral associadas a depressões paleolagunares, cujos terrenos são permanentemente encharcados. Essas florestas se caracterizam por apresentar elevada densidade de indivíduos da espécie Tabebuia cassinoides (Lam. DC., conhecida popularmente por “caxeta”. O presente estudo foi desenvolvido em uma Floresta Paludosa situada na planície costeira do rio Itaguaré, município de Bertioga, Baixada Santista, Estado de São Paulo. A composição florística e a estrutura fitossociológica foram investigadas através da amostragem por parcelas, sendo incluídos todos os indivíduos com 10 cm ou mais de diâmetro a 1,3 m de altura do peito (DAP. Foram registradas 20 espécies e 11 famílias botânicas, resultando em uma densidade total de 450 ind./ha-1. A família com maior riqueza de espécies foi Myrtaceae, com quatro espécies. A análise de similaridade indicou dois grupos florísticos. Tabebuia cassinoides foi, de fato, a espécie mais importante, apresentando grande densidade e dominância de indivíduos, o que reforça sua posição de espécie indicadora deste tipo vegetacional, conforme difundido na literatura. The coastal Paludal Forest or “Caxetal” occurs on the Atlantic Domain, associated to wetlands within palaeolagoonal depressions. It is characterized by a high density of individuals of Tabebuia cassinoides (Lam. DC., which is popularly known as “caxeta”. A Paludal Forest located in the Itaguaré river coastal plain, in the municipality of Bertioga, Santos Lowland, São Paulo State, Brazil was studied. The floristic composition and phytossociological structure was investigated through a plot method including all individuals with diameter at 1.3 m (DBH ≥ 10 cm. A total of 20species and 11 botanic families were sampled, resulting in a total density of 450 ind./ha-1. Myrtaceae showed the highest species richness. The similarity index indicated

  2. Aspectos florísticos e ecológicos de epífitos vasculares sobre figueiras isoladas no norte da planície costeira do Rio Grande do Sul Floristic and ecological aspects of vascular epiphytes on isolated fig trees on the northern coastal plain of Rio Grande do Sul

    Directory of Open Access Journals (Sweden)

    Cezar Neubert Gonçalves

    2003-03-01

    Full Text Available Estudos com epífitos vasculares no Brasil normalmente não consideram árvores isoladas em áreas antropizadas, as quais permitem o estabelecimento e preservação de uma porção representativa da flora epifítica original. Neste trabalho, enfoca-se a composição florística dos epífitos vasculares em espécimes isolados de Ficus organensis (Miq. Miq. no norte da planície costeira do Rio Grande do Sul. A área de estudo fica situada no entorno da cidade de Terra de Areia (29°35' S e 50°04' W, com clima subtropical úmido (Cfa. Sessenta árvores foram inventariadas. Foram encontradas 77 espécies, 33 gêneros e 10 famílias. A família Orchidaceae e o gênero Tillandsia L. apresentaram os maiores números de espécies. A categoria ecológica mais diversificada foi a dos holoepífitos, com 69 espécies, a maioria delas apresentando a suculência como adaptação para o estresse hídrico. A proporção de espécies anemocóricas (51 foi praticamente o dobro das zoocóricas (26. A percentagem das espécies epifíticas, em relação à flora epifítica regional, foi de 30,8%. A proporção de Orchidaceae foi relativamente menor, provavelmente devido a maiores exigências em relação aos hábitats florestais originais. A família com maior importância fisionômica foi Bromeliaceae. O predomínio das espécies anemocóricas sobre as zoocóricas, nas árvores amostradas, é menor do que em áreas com florestas preservadas.Studies on vascular epiphytes in Brazil usually do not consider isolated trees close to anthropic areas. These trees allow the establishment and preservation of a representative proportion of the original epiphytic flora. In this study, the floristic composition of vascular epiphytes was surveyed on isolated specimens of Ficus organensis (Miq. Miq., on the northern coastal plain of Rio Grande do Sul. The study area lies around the city of Terra de Areia (29°35' S; 50°04' W, a region with a humid subtropical climate (Cfa

  3. Caracterização florística da vegetação sobre afloramento rochoso na Estação Experimental de Itapeva, SP, e comparação com áreas de campos rupestres e de altitude. Floristic characterization on rocky outcrop in the Itapeva Experimental Station, SP, and comparison with areas of rocky grasslands and high-altitude grasslands.

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    Silvana Cristina Pereira Muniz de SOUZA

    2011-06-01

    Full Text Available A classificação de comunidades vegetais nem sempre é tarefa fácil, principalmente quando se trata de tipos de vegetação pouco estudados. Esse é o caso davegetação sobre afloramento rochoso da Estação Experimental de Itapeva – EEI, situada no sudoeste do Estado de São Paulo, região que abriga remanescentes de Cerrado e Mata Atlântica. Visando caracterizar e classificar essa vegetação, foram realizadas coletas mensais de material botânico no período de agosto de 2008 a fevereiro de 2010. A lista de espécies obtida foi comparada com a de campos rupestres e de altitude brasileiros. As comparações foram realizadas por meio de análise de agrupamento, “TWINSPAN” e “NMS”. Foram encontradas 135 espécies, 48 famílias e 108 gêneros. As famílias mais representativas foram Fabaceae, Asteraceae, Bignoniaceae, Myrtaceae, Melastomataceae, Poaceae, Apocynaceae, Sapindaceae e Orchidaceae. A análise de agrupamento com os dados de distribuição de riqueza entre famílias sugeriu maior afinidade florística entre o afloramento rochoso estudado e os campos rupestres. Para os dados de composição de espécies, os diferentes métodos de ligação agruparam a área de estudo ora com campos de altitude ora com campos rupestres. A “NMS” evidenciou o caráter contínuo da variação florística, mas reiterou a maior similaridade entre a área de estudo e os campos rupestres. A “TWINSPAN” reforçou essa hipótese e apontou a família Fabaceae e as espécies Miconia albicans (Sw. Steud. e Periandra mediterranea (Vell. Taub como indicadoras de campos rupestres. O tipo de solo, formado a partir de rochas areníticas, constitui o fator determinante mais plausível para as relações florísticas encontradas.The classification of vegetation communities is not an easy task, especially regarding less studied vegetation types. This is the case for rocky outcrop vegetation in the Itapeva Experimental Station – EEI, located in the

  4. Controle biológico de Mycosphaerella fijiensis Morelet agente causal da sigatoka-negra da bananeira (Musa spp.) com Trichoderma spp.

    OpenAIRE

    Cavero, Poholl Adan Sagratzki

    2011-01-01

    O principal problema fitossanitário da cultura da bananeira no Brasil e também em outros países é a sigatoka-negra, causada pelo fungo Micosphaerella fijiensis Morelet, que pode ocasionar perdas de até 100% da produção. A medida mundialmente mais utilizada no controle deste problema em bananais comerciais têm sido pulverizações com fungicidas. Na Amazônia, o uso de fungicidas para o controle da sigatoka-negra torna-se econômica e ecologicamente inviável, face aos custos e aos impactos ambient...

  5. Nutritional value of silk flower hay for lambs Valor nutritional do feno de flor-de-seda para cordeiros

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    Aderbal Marcos de Azevêdo Silva

    2010-12-01

    nutrientes e aumentou a conversão alimentar e o coeficiente de digestibilidade de todos os nutrientes. O balanço de nitrogênio foi semelhante em todos os níveis de feno de flor-de-seda, embora tenha havido tendência de redução na retenção do nitrogênio nos níveis 66 e 100% de feno de flor-de-seda. Nos níveis 0 e 33% de feno de flor-de-seda na dieta, a ingestão de matéria seca (170 e 180 g/dia, o ganho médio diário de peso (84 e 89 g/kg0,75 e a conversão alimentar (4,99 e 5,02 foram satisfatórios. O feno de flor-de-seda pode representar até 16,5% da ingestão total ou 33% do volumoso da dieta de cordeiros.

  6. CONTROLE QUÍMICO DOS PULG��ES Mysus persicae E Brevicoryne brassicae NA CULTURA DA COUVE-FLOR COM INSETICIDAS APLICADOS NA FORMA DE ESGUICHO CHEMICAL CONTROL OF APHIDS Mizus persicae AND Brevicoryne brassicae ON CAULIFLOWER WITH INSECTICIDES APPLIED IN TRANSPLANT HOLES

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    Selby Pereira dos Santos

    2007-09-01

    Full Text Available

    Avaliou-se o controle químico dos pulgões Mysus persicae e Brevicoryne brassicae, em couve-flor, através dos inseticidas Confidor 700 GRDA e Confidor 200 SC, na área experimental da Escola de Agronomia da Universidade Federal de Goiás em maio de 1998. Foram utilizadas duas dosagens para cada um dos inseticidas, um inseticida padrão (Tamaron Br e uma testemunha. Confidor 700 GRDA e Confidor 200 SC, ambos em duas dosagens, foram aplicados em uma única vez nas covas de transplante, com um pulverizador costal, utilizando bico de esguicho. A avaliação dos resultados de M. persicae constou de contagens de ninfas e adultos em folhas escolhidas ao acaso, nas plantas da linha central das parcelas, 35 dias após os tratamentos. A mesma metodologia foi utilizada para a avaliação de B. brassicae 48 dias após o tratamento. O tratamento com Tamaron Br foi aplicado na forma de pulverizações semanais, ocorrendo as avalia

  7. Causal universe

    CERN Document Server

    Ellis, George FR; Pabjan, Tadeusz

    2013-01-01

    Written by philosophers, cosmologists, and physicists, this collection of essays deals with causality, which is a core issue for both science and philosophy. Readers will learn about different types of causality in complex systems and about new perspectives on this issue based on physical and cosmological considerations. In addition, the book includes essays pertaining to the problem of causality in ancient Greek philosophy, and to the problem of God's relation to the causal structures of nature viewed in the light of contemporary physics and cosmology.

  8. Composição florística e estrutura da comunidade de plantas do estrato herbáceo em áreas de cultivo de árvores frutíferas Floristic composition and community structure of understory vegetation in orchard

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    Yuriko A. N. P. Yanagizawa

    1999-12-01

    Full Text Available O objetivo do presente trabalho foi caracterizar, em três épocas, a comunidade de plantas presentes em áreas de cultivo de abacateiro e de nogueira pecan, localizadas na Fazenda Experimental Lageado, da FCA-UNESP, município de Botucatu-SP. Em decorrência da arquitetura da copa e do caráter decíduo das nogueiras, esta área apresenta-se mais ensolarada, o que produz condições ambientais diferentes entre as duas áreas estudadas. Foi estabelecida uma grade retangular composta de 55 parcelas quadradas, contíguas, com 5 m de lado, havendo 40 parcelas sob os abacateiros e 15 sob as nogueiras. As coletas foram realizadas em março, maio e agosto de 1993, quando foram sorteados quadrados de 1x 1 m em cada parcela, de forma a não haver coincidência entre as amostragens realizadas em cada época. Foram levantadas as espécies ocorrentes, sua porcentagem de cobertura e freqüência. Os dados foram analisados através de métodos multivariados, utilizando-se a Análise de Agrupamento para as seis situações (3 épocas x 2 ambientes. Foram coletadas, no total, 54 espécies, distribuídas em 38 gêneros e 19 famílias, sendo Asteraceae e Poaceae as que contribuíram com o maior número de espécies. A riqueza em espécies foi maior na área sob as nogueiras; em ambas as áreas, a riqueza foi maior na estação úmida. Sob os abacateiros, a porcentagem de cobertura total da comunidade apresentou pouca variação temporal, diferindo da área sob as nogueiras onde se observou flutuação deste parâmetro. O padrão de distribuição espacial, para quase todas as populações, foi do tipo agrupado. A similaridade florística foi maior entre as duas áreas dentro de cada época de coleta. A presença constante de espécies como Commelina nudiflora que contribuiu com valores elevados de cobertura nas três épocas de coleta, mostra a necessidade de utilizar métodos de controle permanentes na área do pomar estudado.The main goal of this study was to

  9. Florística e estrutura da comunidade arbórea de um remanescente florestal ripário no município de Guariba, Estado de São Paulo, Brasil. Floristic and structure of the arboreal community of riparian forest remain at Guariba municipality, São Paulo State, Brazil.

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    Nicole Maria Marson DONADIO

    2009-06-01

    Full Text Available O conhecimento sobre a composição eestrutura de comunidades florestais é fundamentalpara embasar ações de conservação e restauração.O objetivo deste trabalho foi realizar olevantamento florístico e descrever a estrutura dacomunidade arbórea de um remanescente florestallocalizado no município de Guariba, Estado de SãoPaulo. Foram alocadas 30 parcelas de 10 x 10 m,para amostrar os indivíduos arbóreos e arbustivoscom diâmetro à altura do peito (DAP ³ 5 cm.Foram encontradas 54 espécies, pertencentes a 47gêneros, distribuídos em 32 famílias botânicas,com índice de diversidade (H’ de 2,67 eequabilidade (J de 0,20. As famílias Meliaceae eFabaceae apresentaram maior riqueza em espécies.Calophyllum brasiliensis, Astronium graveolens,Scheffera morototoni, Xylopia aromatica eProtium widgrenii destacaram-se como as espéciesde maior valor de importância. Foram amostrados420 indivíduos. A presença de espécies do cerradosugere condição de ecótono e a dominância de umaespécie higrófila indica saturação hídrica em parteda área. A distribuição dos indivíduos em classesde tamanho revelou uma comunidade emregeneração com a maioria dos indivíduos com até15,0 cm de DAP e distribuídos entre 7 e 14,9 m,e com estoques de jovens tanto das espéciespioneiras como secundárias podendo garantir ofuturo da comunidade. Em termos sucessionais aárea estudada encontra-se em estádio de médiopara avançado.Knowledge of the composition andstructure of arboreal communities is paramount forconservation and restoration efforts. The mainobjectives of this study were to characterize thearboreal species floristic composition and describethe structure of the arboreal community of aremaining forest located at the municipality ofGuariba, State of São Paulo. Thirty plots of 10 x 10 mwere allocated. In each plot, diameter and heightwere measured for each individual tree withdiameter at breast height (dbh ³ 5 cm. Fifty-fourspecies were

  10. Riqueza de espécies, estrutura e composição florística de uma floresta secundária de 40 anos no leste da Amazônia Species richness, structure, and floristic composition of a 40 years old secondary forest in Eastern Amazon

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    Sâmyrams Carim

    2007-06-01

    Full Text Available A perda de florestas naturais devido a pressões antrópicas levou as florestas secundárias a ocupar uma grande proporção de áreas no leste da Amazônia. Com o objetivo de conhecer as características de uma comunidade arbórea e a estrutura populacional das espécies mais representativas, foram investigadas a riqueza de espécies, a estrutura e a composição florística de uma floresta secundária de 40 anos no município de Bragança (01°11'S e 46°40'W, Estado do Pará, Brasil. A amostragem contou com todos os indivíduos de espécies arbóreas (exceto Arecaceae com DAP > 5 cm em 150 quadrados de 10×10 m. Foram registrados 2.934 indivíduos em 154 espécies, 101 gêneros e 40 famílias. A densidade foi de 1.956,00 ± 643,45 ind ha-1 e a área basal de 17,358 ± 7,952 m² ha-1 com um índice de diversidade de Shannon de 4,030 nats. ind.-1. As espécies com a maior abundância de indivíduos foram Myrcia bracteata, Casearia arborea e Maprounea guianensis. As com maior área basal foram Tapirira guianensis, Croton matourensis e Maprounea guianensis. A riqueza de espécies adaptou-se ao modelo de distribuição lognormal apenas para área basal e não para número de indivíduos. Em 40 anos de sucessão, esta floresta mostra uma grande diversidade de espécies e baixa área basal.The loss of natural forests due to the anthropic pressure carried the secondary forests to occupy great proportions of areas in East of Amazon. With the aim to known the characteristics of a arboreal community and the population structure of the most representative species, it were investigated species richness, structure, and floristic composition of a 40 years old secondary forest in the municipality of Bragança (01°11'S and 46°40'W, Pará State, Brazil. It was sampled all individuals of arboreal species (except Arecaceae with DBH > 5 cm in 150 plots of 10×10 m. It was registered 2,934 individuals in 154 species, 101 genera and 40 families. The density was 1

  11. Causal and causally separable processes

    Science.gov (United States)

    Oreshkov, Ognyan; Giarmatzi, Christina

    2016-09-01

    The idea that events are equipped with a partial causal order is central to our understanding of physics in the tested regimes: given two pointlike events A and B, either A is in the causal past of B, B is in the causal past of A, or A and B are space-like separated. Operationally, the meaning of these order relations corresponds to constraints on the possible correlations between experiments performed in the vicinities of the respective events: if A is in the causal past of B, an experimenter at A could signal to an experimenter at B but not the other way around, while if A and B are space-like separated, no signaling is possible in either direction. In the context of a concrete physical theory, the correlations compatible with a given causal configuration may obey further constraints. For instance, space-like correlations in quantum mechanics arise from local measurements on joint quantum states, while time-like correlations are established via quantum channels. Similarly to other variables, however, the causal order of a set of events could be random, and little is understood about the constraints that causality implies in this case. A main difficulty concerns the fact that the order of events can now generally depend on the operations performed at the locations of these events, since, for instance, an operation at A could influence the order in which B and C occur in A’s future. So far, no formal theory of causality compatible with such dynamical causal order has been developed. Apart from being of fundamental interest in the context of inferring causal relations, such a theory is imperative for understanding recent suggestions that the causal order of events in quantum mechanics can be indefinite. Here, we develop such a theory in the general multipartite case. Starting from a background-independent definition of causality, we derive an iteratively formulated canonical decomposition of multipartite causal correlations. For a fixed number of settings and

  12. Causal and causally separable processes

    International Nuclear Information System (INIS)

    Oreshkov, Ognyan; Giarmatzi, Christina

    2016-01-01

    The idea that events are equipped with a partial causal order is central to our understanding of physics in the tested regimes: given two pointlike events A and B , either A is in the causal past of B , B is in the causal past of A , or A and B are space-like separated. Operationally, the meaning of these order relations corresponds to constraints on the possible correlations between experiments performed in the vicinities of the respective events: if A is in the causal past of B , an experimenter at A could signal to an experimenter at B but not the other way around, while if A and B are space-like separated, no signaling is possible in either direction. In the context of a concrete physical theory, the correlations compatible with a given causal configuration may obey further constraints. For instance, space-like correlations in quantum mechanics arise from local measurements on joint quantum states, while time-like correlations are established via quantum channels. Similarly to other variables, however, the causal order of a set of events could be random, and little is understood about the constraints that causality implies in this case. A main difficulty concerns the fact that the order of events can now generally depend on the operations performed at the locations of these events, since, for instance, an operation at A could influence the order in which B and C occur in A ’s future. So far, no formal theory of causality compatible with such dynamical causal order has been developed. Apart from being of fundamental interest in the context of inferring causal relations, such a theory is imperative for understanding recent suggestions that the causal order of events in quantum mechanics can be indefinite. Here, we develop such a theory in the general multipartite case. Starting from a background-independent definition of causality, we derive an iteratively formulated canonical decomposition of multipartite causal correlations. For a fixed number of settings and

  13. Análise comparativa da florística e fitossociologia da vegetação arbórea do cerrado sensu stricto na Chapada Pratinha, DF - Brasil Comparative analysis of floristics and plant sociology in the "cerrado" arboreal vegetacion sensu stricto in the Chapada Pratinha, DF-Brazil

    Directory of Open Access Journals (Sweden)

    Jeanini Maria Felfili

    1992-12-01

    Full Text Available Foram selecionadas seis áreas de estudo, Estação Ecológica de Aguas Emendadas-DF, Parque Nacional de Brasília-DF, APA Gama-Cabeça do Veado-DF, Silvânia-GO, Paracatu-MG e Patrocínio-MG na Chapada Pratinha (15-20º S e 46-49º W, três delas em unidades de conservação e três fora delas. Em cada área foram amostradas 10 parcelas de 1000 m² (20x50m. Todas as árvores a partir de 5 cm de diâmetro na base do tronco foram medidas e identificadas. A florística e a fitossociologia de cada área foi analisada e estas foram comparadas entre si pelos índices de similaridade de Sørense e de Morisita. No total foram encontradas 139 espécies e 42 famílias sendo que apenas 22 espécies foram comuns a todas as áreas. Leguminosae e Vochysiaceae apresentaram valores de importância elevados em todas as áreas. As densidades por ha variaram de 664 a 1396. Os índices de diversidade de Shannon variaram de 3,11 a 3.56. As similaridades foram altas pelo índices de Sorensen, de 0,5 a 0,7, porém baixas pelo de Morisita quando se comparou as áreas de Paracatu e Patrocínio com as demais áreas. Foi concluído que as diferenças florísticas e principalmente estruturais foram elevadas entre estas duas áreas que são mais distantes e se situam a menores altitudes do que aquelas situadas nas unidades de conservação existentes na chapada sendo sugerida a criação de novas unidades nestes Municípios.Six sites were surveyed at Chapada Pratinha in Brazil (15-20º S e 46-49º W. Three of them were localized in conservation units in the Federal District and the others were in Silvania-GO, Paracatu-MG e Patroci'nio-MG. Ten plots of 1000 m2 (20x50m were sampled in each site. The minimum diameter for measurement of the woody plants was 5 cm at 0.30 m from the ground level. Floristic composition, importance value index and Shannon's diversity index were analyzed for each area. Sørense's and Morisita's similarity indices were used to compare the six sites

  14. Diversidade fenotípica e patogênica de Colletotrichum, agente causal da antracnose em mangueira, e identificação de espécie

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    I.M.R.S. Serra

    2011-03-01

    Full Text Available O presente trabalho teve como objetivo estudar a diversidade fenotípica e patogênica de 40 isolados de Colletotrichum obtidos de mangueira no Nordeste do Brasil e identificar diferentes espécies desse fitopatógeno, agente causal de antracnose, através da análise da seqüência da região ITS do rDNA. Quanto à caracterização morfológica e cultural, as colônias dos isolados apresentaram diversidade em relação à cor e aspecto, sendo mais comum à cor branco-cinza, característica de Colletotrichum gloeosporioides. Não foram observadas variações expressivas na morfologia dos 40 isolados. Os conídios apresentaram-se, predominantemente, hialinos e unicelulares, com formato variando de bastonete para cilíndrico. Todos os isolados produziram apressórios variados em formato e quantidade e apenas 10 isolados apresentaram setas. Para efeito do crescimento micelial e taxa de crescimento foi possível classificar os isolados em sete grupos. Vinte e dois isolados exibiram taxa de crescimento >10mm/dia, considerada típica da espécie C. gloeosporioides. Os isolados foram patogênicos em folhas destacadas de mangueira, induzindo sintomas de antracnose, na forma de manchas escuras levemente deprimidas, e apresentando variações quanto à agressividade. Na identificação específica, baseada na análise da seqüência ITS do DNA ribossomal, 36 isolados amplificaram com o oligonucleotídeos CgInt, específico para C. gloeosporioides e o ITS4, Os isolados CM1, CM4, CM5 e CM10, não amplificaram produtos para nenhum dos oligonucleotídeos específicos, sendo identificados como Colletotrichum spp. Os resultados desse trabalho demonstraram que isolados de Colletotrichum, obtidos de mangueira, apresentam ampla variabilidade morfofisiológica e patogênica. E que, possivelmente, existe mais de uma espécie de Colletotrichum que causa antracnose em mangueira no Nordeste do Brasil.

  15. Gramíneas hospedeiras de Xanthomonas sp., agente causal da falsa estria vermelha da cana-de-açúcar Host range of Xanthomonas sp., causal agent of the false red stripe of sugarcane, among grasses

    Directory of Open Access Journals (Sweden)

    Elaine Spindola Mantovani

    2006-06-01

    Full Text Available Falsa estria vermelha (FEV, uma nova doença causada por Xanthomonas sp., é diferente diferente de todas as outras doenças já descritas em cana-de-açúcar. Ela está distribuída por toda as principais regiões canavieiras do centro-sul do Brasil, mas ainda não foi detectada no norte e nordeste do Brasil nem em qualquer outro país. O presente estudo determinou a gama de culturas e plantas daninhas hospedeiras da bactéria dentre espécies pertencentes às gramíneas, através de inoculação por injeção e pulverização de suspensão bacteriana. Além da cana-de-açúcar, entre as 31 diferentes espécies estudadas, apenas sorgo, milho e aveia apresentaram sintomas, 15 dias após a inoculação. Em sorgo, no ponto de inoculação, apareceram estrias avermelhadas coalescentes. As folhas apresentaram típicas estrias vermelhas finas (1 mm, longas e paralelas às nervuras, com presença de exsudato bacteriano. Até mesmo as inflorescências apresentaram pontuações avermelhadas. Plantas de milho inoculadas com seringa apresentaram sintomas de anasarca e descoloração de tecidos ao redor do ponto de inoculação e estrias cloróticas (2-3 mm no limbo foliar; porém, sem exsudato de bactéria. Apenas folhas de cevada apresentaram sintomas quando inoculadas por pulverização. As lesões iniciais eram estrias e manchas de cor palha, evoluindo para uma necrose total das folhas, causando a morte das plantas. A partir de folhas sintomáticas de cana-de-açúcar, sorgo, milho e aveia, realizaram-se re-isolamentos, obtendo-se culturas puras de Xanthomonas sp. cuja identidade foi comprovada através de testes sorológicos e por Rep-PCR. Diante desses resultados, surge a necessidade de realização de inspeções e campos de cultivo de sorgo, milho e aveia para verificar a presença da bactéria da FEV e determinar se o patógeno pode infectar essas culturas naturalmente.False Red Stripe (FRS, a new disease caused by Xanthomonas sp., is different

  16. Nexo causal em matéria penal: análise da jurisprudência dos tribunais de justiça Case law regarding causal relationship between conduct and result to attribute criminal liability in brazilian state supreme courts

    Directory of Open Access Journals (Sweden)

    Luisa Moraes Abreu Ferreira

    2011-06-01

    Full Text Available Este artigo discute uma pesquisa empírica apresentada em 2009 como Trabalho de Conclusão de Curso na Direito GV sobre a definição da causalidade para responsabilização criminal nos tribunais de justiça. Foram analisadas 84 apelações criminais julgadas entre 2007 e 2008 e extraídos resultados quantitativos e qualitativos relacionados aos dados do processo, ao resultado da decisão e à argumentação. A análise desses resultados levou a cinco principais constatações: (1 a discussão sobre nexo causal ocorre quase exclusivamente em casos de crimes culposos; (2 muitas vezes, apesar de discutido pelas partes, a existência de nexo causal não é afirmada no acórdão; (3 o nexo causal é frequentemente afirmado com pouca fundamentação e, em geral, com menos argumentos do que a afirmação de culpa; (4 a teoria mais utilizada pelos tribunais é a da equivalência das condições; e (5 o nexo causal é frequentemente afirmado como decorrência da culpa.This paper reports empirical research presented in 2009 as final dissertation for graduation as bachelor of laws at direito gv about the definition of causation to attribute criminal liability in the brazilian state supreme Courts. A total of 84 criminal appeals, ruled between 2007 and 2008, were analyzed and quantitative and qualitative results related to procedure data, results of the decision and reasoning were extracted. Analysis of these results led to five major findings: (1 discussion of causation occurs almost exclusively in cases of willful crimes, (2 often, though discussed by the parties, a causal relationship is not asserted in the decision, (3 causal relationship is often stated with little reasoning and, generally, with fewer arguments than the statement of negligence, (a the causal theory most used by the courts is that cause is every necessary condition for the event, and (5j causal relationship is often asserted as a result of negligence.

  17. Composição lignocelulósica e isótopica da vegetação e da matéria orgânica do solo de uma turfeira tropical: I - composição florística, fitomassa e acúmulo de carbono

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    Vinicius Evangelista Silva

    2013-02-01

    Full Text Available A matéria orgânica do solo (MOS é um dos grandes reservatórios de carbono (C da Terra e constitui um dos principais componentes do ciclo do C. Turfeiras, ambientes acumuladores de MOS, são produto da decomposição de vegetais, que se desenvolvem e se acumulam em ambientes saturados com água, sendo o estádio inicial da sequência de carbonificação. A fitomassa participa de forma marcante no ciclo global do C, armazenando em torno de 85 % de todo o C terrestre acima do solo. O tecido vegetal é composto principalmente por lignina, celulose e hemicelulose, constituindo até 85 % da biomassa seca. As plantas discriminam C de forma diferenciada, em razão de seu ciclo fotossintético (C3, C4 e CAM. As turfeiras da Serra do Espinhaço Meridional (SdEM-MG são colonizadas por vegetação de Campo Limpo Úmido (CLU e de Floresta Estacional Semidecidual (FES, onde ocorrem espécies dos ciclos fotossintéticos C3 e C4. Este trabalho objetivou avaliar a contribuição dessas duas fitofisionomias para o acúmulo de MOS, por meio da avaliação da fitomassa e da composição lignocelulósica e isotópica da vegetação e da MOS. A turfeira estudada localiza-se na SdEM e ocupa 81,75 ha. Para a estimativa da fitomassa do CLU e da FES, foram marcadas três parcelas de 0,5 x 0,5 m em cada fitofisionomia, onde todos os indivíduos da parcela foram cortados e armazenados. Para as análises isotópicas e lignocelulósicas da vegetação, identificaram-se as espécies dominantes em cada fitofisionomia. Amostras de solo foram coletadas em três locais representativos sob cada fitofisionomia, a cada 5 cm de profundidade, até 50 cm. Foram extraídas a celulose e a lignina das folhas das 15 espécies dominantes e das 60 amostras de turfeira para quantificação e determinação dos valores de δ13C e δ15N. Para datação da MOS, o 14C foi determinado em três profundidades, sob o CLU e a FES. A produção da fitomassa da FES foi muito superior à produ

  18. Gastronomia sensual: análise simbólica de A festa de Babette e Dona Flor e seus dois maridos = Sensual gastronomy: symbolic analysis of Babetes fiest and Dona Flor e seus dois maridos

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    Rocha, Gilmar

    2009-01-01

    Full Text Available O texto apresenta uma análise simbólica sobre a representação do gênero feminino dramatizada nos filmes Dona Flor e seus dois maridos (1976 e A festa de Babette (1987. Ambientados em contextos socio-históricos diferentes, tais filmes podem ser vistos como “etnografias” que falam do imaginário religioso e do ethos cultural protestante na Dinamarca de fins do século 19 e do sincretismo afro-brasileiro da primeira metade do século 20. O ponto de vista da antropologia simbólica, alimentada pelas contribuições teóricas de Clifford Geertz, Marcel Mauss, Victor Turner e Roberto DaMatta, orienta a interpretação dos filmes a partir dos códigos culturais da culinária (comida, da corporalidade (sexualidade e da religiosidade (puritanismo e sincretismo. Destaca-se, nessas “etnografias fílmicas”, o modo como os sistemas da dádiva e da carnavalização que as estruturam convergem para um mesmo campo de significação. A estratégia metodológica adotada consiste em comparar os filmes tendo por base a estrutura conceitual dos “dramas sociais”

  19. Epidemiological causality.

    Science.gov (United States)

    Morabia, Alfredo

    2005-01-01

    Epidemiological methods, which combine population thinking and group comparisons, can primarily identify causes of disease in populations. There is therefore a tension between our intuitive notion of a cause, which we want to be deterministic and invariant at the individual level, and the epidemiological notion of causes, which are invariant only at the population level. Epidemiologists have given heretofore a pragmatic solution to this tension. Causal inference in epidemiology consists in checking the logical coherence of a causality statement and determining whether what has been found grossly contradicts what we think we already know: how strong is the association? Is there a dose-response relationship? Does the cause precede the effect? Is the effect biologically plausible? Etc. This approach to causal inference can be traced back to the English philosophers David Hume and John Stuart Mill. On the other hand, the mode of establishing causality, devised by Jakob Henle and Robert Koch, which has been fruitful in bacteriology, requires that in every instance the effect invariably follows the cause (e.g., inoculation of Koch bacillus and tuberculosis). This is incompatible with epidemiological causality which has to deal with probabilistic effects (e.g., smoking and lung cancer), and is therefore invariant only for the population.

  20. Bignoniaceae Juss. do Parque Estadual do Itacolomi, Minas Gerais, Brasil: florística, similaridade e distribuição geográfica

    OpenAIRE

    Araújo, Ricardo de Souza

    2008-01-01

    Este trabalho consiste do levantamento florístico de Bignoniaceae do Parque Estadual do Itacolomi (PEI), Minas Gerais, da distribuição geográfica das espécies e da similaridade entre trilhas do PEI e entre outras áreas do Brasil. As coletas foram realizadas mensalmente em 15 trilhas pré- estabelecidas, sendo sete em campo rupestre e oito em Floresta Estacional Semidecídua, totalizando 15 expedições de agosto/2006 a outubro/2007. O material foi herborizado e incorporado ao acervo do Herbário V...

  1. Conexões florísticas e funcionamento de comunidades arbóreas associadas à inselberg no domínio atlântico

    OpenAIRE

    Paula, Eduardo de Paiva

    2014-01-01

    A presente dissertação encontra-se estruturada em dois artigos. No primeiro, objetivou-se, compreender as relações fitogeográficas de três comunidades arbóreas associadas a um inselberg,em Minas Gerais (Serra da Canoa), através da análise florística de 22 localidades/unidades florestais , em diferentes escalas geográficas do mesmo Estado, incluindo três comunidades arbóreas associadas a outro inselberg, em MG. Foram utilizadas duas técnicas de analise multivariada: Análise de correspondência ...

  2. Composição florística da regeneração natural de espécies arbóreas ao longo de oito anosem um fragmento de floresta estacional semidecidual, em Viçosa, MG Floristic composition of natural regeneration of tree species in a mountain seasonal semideciduous florest fragment over an eigth year period, in Viçosa, MG, Brazil

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    Pedro Higuchi

    2006-12-01

    Full Text Available A florística da regeneração natural foi estudada em 10 locais, com seis sub-parcelas em cada local, em 1992, 1995 e 2000, em fragmento de Floresta Estacional Semidecidual Montana, em Viçosa, MG. A amostragem da classe 1 de tamanho de planta (até 1 m de altura, classe 2 (1-3 m de altura e classe 3 (>3 m de altura e The floristic composition of the natural regeneration in a secondary Seasonal Semideciduous Forest fragment in the Atlantic Forest domain, Southeastern Brazil, was studied in the years 1992, 1995 and 2000. The sampling unit sizes were 0.5x10m, 0.5x20m and 1x20m, respectively, for plant size class 1 (height up to 1 m, class 2 (height from 1 to 3 m and class 3 (height > 3m and DBH < 5cm. A total of 4,149 individuals were sampled over the inventory period, comprising 42 families and 160 species, being 11.7 % pioneer, 62.1 % early secondary, and 26.2 % late secondary species. Family number did not change and number of species increased with time. Fabaceae, Myrtaceae, Rubiaceae and Lauraceae were the predominant families. Species ingrowth was higher than mortality. Shannon-Weaver diversity index was significantly lower (P < 0.05 only for the plant size class 1 as compared to the other size classes, in 1992, and it increased significantly from 3.45 (average of all plant size classes, in 1992, to 3.67 and 3.64 in 1995 and 2000, respectively. The Pielou equability index per inventory date varied from 0.71 to 0.74, and it was 0.71; 0. 79 and 0.82 for the size classes 1, 2 and 3, respectively. Overall, the results showed that monitoring the natural regeneration over an age sequence is important to understand the dynamics of the secondary forest fragments.

  3. Florística e estrutura da vegetação arbórea de um fragmento de floresta semidecedual às margens do reservatório da usina hidrelétrica Dona Rita (Itambé do Mato Dentro, MG Floristic composition and structure of the tree community of a fragment of the submontane semideciduous forest in Itambé do Mato Dentro Minas Gerais State, south-eastern Brazil

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    Douglas Antônio de Carvalho

    2000-04-01

    Full Text Available Realizou-se o levantamento florístico e fitossociológico da comunidade arbórea de um fragmento de Floresta Estacionai Semidecidual Sub-Montana localizado às margens do reservatório da usina hidrelétrica Dona Rita, situado na Fazenda Camarinha, em Itambé do Mato Dentro, MG, na bacia do rio Doce (19º26'S, 43º 14' W, altitude entre 610 e 630m. Todos os indivíduos com diâmetro do caule à altura do solo > 5,0cm (exceto lianas encontrados em 35 parcelas de 15xl5m (0,78ha foram identificados, medidos e tiveram sua altura estimada (também foram coletados indivíduos que se apresentavam com estruturas reprodutivas, fora das parcelas. Foram estimados para cada espécie os seguintes parâmetros: densidade por área, freqüência absoluta, dominância absoluta e índice de valor de importância (IVI. Também foram calculados o índice de diversidade de Shannon e a equabilidade correspondente, o índice de similaridade de Jaccard e as distâncias euclidianas quadradas entre esta floresta e outras do alto e médio Rio Grande, baixo Paranaíba e alto São Francisco. Nas parcelas foram amostrados 2.430 indivíduos. Identificou-se 216 espécies (15 fora das parcelas pertencentes a 50 famílias e 144 gêneros. Destacam-se pelo IVI as famílias Euphorbiaceae, Myrtaceae e Caesalpiniaceae e as espécies Apuleia leiocarpa, Pera glabrata, Licania hypoleuca e Mabeafistulifera. Comparada com algumas florestas ciliares do Estado, a floresta de Itambé do Mato Dentro se assemelha mais com a do alto Rio Grande (ambas localizadas em regiões sob influência da Mata Atlântica, muito embora as espécies mais importantes não sejam as mesmas. Em termos pedológicos a floresta de Itambé apresenta os solos mais intemperizados, lixiviados e profundos, apesar de seu relevo íngreme, devido ao material constitutivo dos mesmos ter sofrido intenso processo de alteração anterior ao atual ciclo pedogênico.A floristic and phytosociological survey of the tree commnunity

  4. Levantamento florístico e fitofisionomia da lagoa Figueira e seu entorno, planície alagável do alto rio Paraná, Porto Rico, Estado do Paraná, Brasil - DOI: 10.4025/actascibiolsci.v25i1.2091 Floristic survey and phytophysiognomy of the Figueira pond in the upper Paraná River floodplain, in Porto Rico, state of Paraná, Brazil - DOI: 10.4025/actascibiolsci.v25i1.2091

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    Maria Conceição de Souza

    2003-04-01

    Full Text Available Foi realizada uma caracterização botânica da lagoa Figueira (planície alagável do alto rio Paraná, Porto Rico, Estado do Paraná, Brasil, a 22o45’36’’S e 53ol5’56’’W, empregando-se levantamentos florísticos e perfis fitofisionômicos em diferentes períodos fluviométricos, além de uma carta batimétrica e análise do solo. O levantamento florístico resultou no reconhecimento de 36 famílias, 75 gêneros e 89 espécies. As famílias de maior riqueza específica foram Poaceae (14 espécies, seguida por Cyperaceae e Euphorbiaceae (oito cada. O porte predominante pertenceu ao herbáceo (79,78% das espécies e, quanto à forma biológica, houve predominância das terrestres (50,56% e das anfíbias (37,08%. A fitofisionomia, com predominância de herbáceas, apresenta diferenciações entre as margens e ao longo da lagoa, havendo uma considerável diminuição da cobertura vegetal no período de águas altas. Essa lagoa foi considerada um corpo de água raso, com solo tipo argilosoA botanical characterization of the Figueira pond (Upper Paraná River floodplain, in Porto Rico, State of Paraná, Brazil, at 22o45’36’’ S and 53ol5’56’’ W has been carried out using floristic surveys and phytophysiognomic profiles, in different water periods, together with a bathymetric chart and a soil analysis. The floristic survey resulted in 36 families, 75 genera and 89 species. The families with more specific richness were Poaceae (14 species, followed by Cyperaceae and Euphorbiaceae (eight each. The highest habit incidence belonged to the herbaceous (79,78% of the species and, concerning the biological form, there was predominance of the terrestrial (50,56% and amphibious ones (37,08%. The phytophysiognomy, with predominance of herbaceous, shows differentiation between the banks and along the pond, with a considerable decrease of the vegetal covering in the high water periods. This pond was considered a shallow body of water, with

  5. Florística, fitossociologia e diversidade da vegetação arbórea nas matas de galeria do Parque Nacional de Sete Cidades (PNSC, Piauí, Brasil Floristics, phytosociology and diversity of tree vegetation in gallery forests of Sete Cidades National Park (PNSC, Piauí, Brazil

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    Mariana de Queiroz Matos

    2010-06-01

    Full Text Available O presente estudo foi realizado nas matas de galeria do Parque Nacional de Sete Cidades (PNSC, área prioritária para conservação do Cerrado. Teve como objetivos estudar a composição florística, fitossociologia e diversidade das matas de galeria que se distribuem ao longo dos cursos d’água localizados no PNSC e avaliar a similaridade florística destas com outras matas em diversas localidades do Cerrado. A vegetação arbórea (DAP > 5 cm foi amostrada em quatro trechos de mata ao longo do Parque, cada um subdividido em transectos (equidistantes em 50 m e perpendiculares ao leito do córrego principal, onde sistematicamente foram alocadas 56 parcelas de 10 x 10 m (0,01 ha. Foram encontradas 75 espécies arbóreas pertencentes a 64 gêneros e 30 famílias. A família de maior riqueza na amostragem foi Fabaceae (14 espécies. Virola surinamensis foi a espécie de maior valor de importância (VI na amostragem.Estimou-se uma densidade absoluta de 1.146,43 ind ha-1 e área basal de 26,55 m² ha-1. A diversidade alfa, obtida por meio do Índice de Shannon (H’, foi de 3,53 e a equabilidade de Pielou (J’ de 0,82. A diversidade beta entre o Parque e outras localidades do bioma Cerrado foi elevada. As matas de galeria do PNSC apresentam alta riqueza e diversidade florística, compartilham espécies com matas em localidades diversas e contêm espécies típicas a outros biomas, evidenciando a localização geográfica do Parque em "área de tensão ecológica".This study was undertaken in the gallery forests of Sete Cidades National Park (PNSC, a priority area for conservation of the Cerrado. The objective was to study the floristic composition, phytosociology and diversity of the gallery forests distributed along the river courses located in PNSC and also evaluate floristic similarity between these forests and others in the Cerrado biome. The tree vegetation (DAP > 5 cm was sampled in four sections of forest in the Park, each subdivided into

  6. Differential Proteome Analysis of a Flor Yeast Strain under Biofilm Formation.

    Science.gov (United States)

    Moreno-García, Jaime; Mauricio, Juan Carlos; Moreno, Juan; García-Martínez, Teresa

    2017-03-28

    Several Saccharomyces cerevisiae strains (flor yeasts) form a biofilm (flor velum) on the surface of Sherry wines after fermentation, when glucose is depleted. This flor velum is fundamental to biological aging of these particular wines. In this study, we identify abundant proteins in the formation of the biofilm of an industrial flor yeast strain. A database search to enrich flor yeast "biological process" and "cellular component" according to Gene Ontology Terminology (GO Terms) and, "pathways" was carried out. The most abundant proteins detected were largely involved in respiration, translation, stress damage prevention and repair, amino acid metabolism (glycine, isoleucine, leucine and arginine), glycolysis/gluconeogenesis and biosynthesis of vitamin B9 (folate). These proteins were located in cellular components as in the peroxisome, mitochondria, vacuole, cell wall and extracellular region; being these two last directly related with the flor formation. Proteins like Bgl2p, Gcv3p, Hyp2p, Mdh1p, Suc2p and Ygp1p were quantified in very high levels. This study reveals some expected processes and provides new and important information for the design of conditions and genetic constructions of flor yeasts for improving the cellular survival and, thus, to optimize biological aging of Sherry wine production.

  7. A rede de causalidade da insegurança alimentar e nutricional de comunidades quilombolas com a construção da rodovia BR-163, Pará, Brasil The causality of nutrition and food insecurity of quilombola communities with the construction of the BR-163, highway, Pará, Brazil

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    Denise Oliveira e Silva

    2008-08-01

    Full Text Available OBJETIVO: Trata-se da descrição de resultados baseados na elaboração de um modelo de determinação causal de forma participativa e abrangente, realizada em seis comunidades quilombolas no município de Santarém, no Estado do Pará, sobre a rede de causalidade da insegurança alimentar e nutricional com a abertura da Rodovia BR-163. MÉTODOS: O processo investigativo utilizou métodos de abordagem sócio-antropológica tendo como base o desenvolvimento de um modelo de causalidade construído por meio da realização de grupos focais com representantes da comunidade. RESULTADOS: Os resultados do estudo demonstraram que a utilização de abordagens participativas estimula a auto-estima da comunidade e o empoderamento sobre os fatores que determinam seus problemas. O modelo causal construído revela que a insegurança alimentar e nutricional, para as comunidades, estabelece que fatores históricos relacionados à posse da terra e ao seu uso atual baseado em práticas predatórias, são os aspectos fundamentais na compreensão da rede de determinação causal da insegurança alimentar e nutricional. CONCLUSÃO: O racismo e suas nuances sociais têm contribuído para a invisibilidade social dessas comunidades nas políticas públicas brasileiras. As comunidades quilombolas se consideram em insegurança alimentar e nutricional e indicam que a abertura da Rodovia BR-163 pode ser uma ameaça ao etno-desenvolvimento sustentável na região. E referem que o desenvolvimento econômico esperado com a abertura desta rodovia, se não for realizado com base na participação da comunidade, pode aumentar a fome, a miséria e o racismo.OBJECTIVE: This work describes results based on the participative and encompassing development of a model of causal determination done in six quilombola communities of Santarém, Pará State, regarding the causality of food and nutrition insecurity with the construction of the BR-163 highway. METHODS: The research process

  8. Efeito de Trilhas sobre Artrópodes de Serrapilheira no Parque Nacional da Tijuca, RJ

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    Felipe Drummond-Alves

    2017-07-01

    Full Text Available RESUMO Foi analisado o efeito de trilhas sobre a comunidade de artrópodes de serrapilheira em duas trilhas do Parque Nacional da Tijuca. Amostras de serrapilheira foram coletadas em duas cotas altitudinais (650 e 850 m anm e em três classes de distância (0, 5 e 10 m. Os artrópodes foram identificados ao nível de ordem. Foram amostrados 4.491 indivíduos de 19 taxa, sendo Orthoptera a mais frequente. Foram encontradas diferenças significativas no número de táxons entre trilhas, possivelmente como resposta a um efeito causal da estrutura e da composição florística das trilhas e das cotas. A trilha que apresentou os maiores valores de riqueza foi a do Bico do Papagaio, diferindo da trilha do Pico da Tijuca. Concluiu-se que as diferenças encontradas podem estar relacionadas com o grau de perturbação diferenciado que as duas trilhas sofrem. No entanto, análises mais detalhadas poderão tornar os resultados mais claros.

  9. Proteins involved in flor yeast carbon metabolism under biofilm formation conditions.

    Science.gov (United States)

    Moreno-García, Jaime; García-Martínez, Teresa; Moreno, Juan; Mauricio, Juan Carlos

    2015-04-01

    A lack of sugars during the production of biologically aged wines after fermentation of grape must causes flor yeasts to metabolize other carbon molecules formed during fermentation (ethanol and glycerol, mainly). In this work, a proteome analysis involving OFFGEL fractionation prior to LC/MS detection was used to elucidate the carbon metabolism of a flor yeast strain under biofilm formation conditions (BFC). The results were compared with those obtained under non-biofilm formation conditions (NBFC). Proteins associated to processes such as non-fermentable carbon uptake, the glyoxylate and TCA cycles, cellular respiration and inositol metabolism were detected at higher concentrations under BFC than under the reference conditions (NBFC). This study constitutes the first attempt at identifying the flor yeast proteins responsible for the peculiar sensory profile of biologically aged wines. A better metabolic knowledge of flor yeasts might facilitate the development of effective strategies for improved production of these special wines. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Análise florística e estrutural de um fragmento de Floresta Ombrófila Mista Montana, situado em Criúva, RS - Brasil.

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    Rubens Marques Rondon Neto

    2010-08-01

    Full Text Available O presente trabalho teve como objetivo conhecer e analisar a composição florística e descrever a estrutura do componente arbóreo de um fragmento de Floresta Ombrófila Mista Montana, localizado no município de Criúva, RS. Em oito parcelas de 10 x 100 m foram inventariados 673 indivíduos com DAP  5 cm, distribuídos em 37 espécies, pertencentes a 32 gêneros e 22 famílias. O valor do índice de diversidade de Shannon foi de 2,768. As famílias que apresentaram maior número de indivíduos amostrados são: Araucariaceae, Myrsinaceae, Euphorbiaceae, Anacardiaceae e Rutaceae. O dossel dessa floresta é dominado pela Araucaria angustifolia e o sub-bosque por espécies das famílias Lauraceae e Myrtaceae. A densidade total encontrada foi de 841,25 indivíduos/ha, com DAP médio de 24,01 cm e altura média de 9,34 m. As cinco espécies que tiveram os maiores valores de importância, em ordem decrescente, foram: Araucaria angustifolia, Sebastiania commersoniana, Lithraea brasiliensis, Zanthoxylum rhoifolium e Myrcia sp.. O fragmento apresenta uma considerável diversidade florística de espécies, apesar das perturbações sofridas no passado. Para que a vegetação atinja as características florísticas e estruturais próximas às da vegetação original é preciso evitar a presença de bovinos e eqüinos na área e explorações da floresta.

  11. Resistência de variedades comerciais de cana-de-açúcar ao agente causal do raquitismo-da-soqueira Resistance of sugarcane commercials cultivars to causal agent of ratoon stunting disease

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    Paulo Roberto Gagliardi

    2009-07-01

    Full Text Available O raquitismo-da-soqueira (RSD, causado pela bactéria Leifsonia xyli subsp. xyli, é uma das mais importantes doenças da cana-de-açúcar nas regiões produtoras do mundo. O presente trabalho teve como objetivo avaliar o grau de resistência de 10 variedades comerciais RB de cana-de-açúcar mais a variedade CB 49-260, a qual foi incluída como padrão suscetível. O trabalho visou avaliar os danos amostrados em campo pelo peso das parcelas em função da relação entre a produtividade de parcelas inoculadas e não inoculadas artificialmente com a bactéria. Os resultados mostraram que as variedades RB 72 454, RB 83 5486, RB 86 7515, RB 92 5211, RB 92 5268, RB 92 5345, RB 92 8064 e a variedade padrão CB 49-260 comportaram-se como variedades suscetíveis. A variedade RB 85 5156 comportou-se como de resistência intermediária e apenas as variedades RB 85 5453 e RB 85 5536 comportaram-se como tolerantes.Ratoon stunting disease (RSD caused by bacteria Leifsonia xyli subsp. xyli is one of the most economically important disease of sugarcane worldwide. The present survey had objective to evaluate the resistance of 10 RB commercial cultivars of sugarcane including CB 49-260 as a susceptible standard. The study evaluated the correlating the damages presented for overhauls productivity of inoculate and non inoculate parcels with the bacteria. The results showed that varieties RB 72 454, RB 83 5486, RB 86 7515, RB 92 8064, RB 92 5211, RB 92 5345 and RB 92 5268 were susceptible. RB 85 5156 had a intermediary resistance and varieties RB 85 5453 and RB 85 5536 both showed tolerant behavior.

  12. Estrutura e relações ambientais de grupos florísticos em fragmento de floresta estacional subtropical

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    Suzane Bevilacqua Marcuzzo

    2013-04-01

    Full Text Available Este estudo teve por objetivos analisar a estrutura de grupos florísticos na vegetação arbórea-arbustiva de um trecho de encosta de Floresta Estacional Subtropical, no Parque Estadual Quarta Colônia, RS, e determinar fatores ambientais importantes na ocorrência das espécies, a fim de subsidiar programas de restauração de áreas degradadas como ecossistema de referência. Para isso, foi realizado estudo fitossociológico em 12 parcelas de 200 m² (10 x 20 m, distantes 20 m entre si, distribuídas sistematicamente em quatro faixas de 100 m entre si, seguindo gradiente de topografia. Em cada parcela foram realizadas a identificação e a medição da circunferência à altura do peito (CAP e da altura total dos indivíduos arbóreos e arbustivos, ou seja, com CAP > 15 cm, denominado componente arbóreo. Os dados do sub-bosque foram obtidos em parcelas circulares com raio de 1,78 m, instaladas no centro das parcelas de 10 x 20 m, medindo-se indivíduos com altura > 30 cm e CAP <15 cm. As variáveis ambientais foram compostas pela declividade, pela intensidade luminosa, pelas características químicas e textura do solo. Os dados foram analisados segundo a estrutura e diversidade da vegetação por meio da análise de agrupamento pelo método TWINSPAN (Two-way Indicator Species Analysis e da ordenação pelo método CCA (Análise de Correspondência Canônica. Foi identificada a formação de dois grupos florísticos. A composição de espécies de cada grupo pertence a diferentes estágios de sucessão natural, conforme histórico de uso agrícola, e, segundo suas características funcionais, podem ser indicadas para programas de restauração florestal.

  13. EFEITO DE DIFERENTES TEMPOS DE COZIMENTO NOS TEORES DE FIBRAS ALIMENTARES EM FOLHAS DE BRÓCOLIS, COUVE-FLOR E COUVE (BRASSICA OLERACEA L.

    Directory of Open Access Journals (Sweden)

    Mônica Alessandra Teixeira dos SANTOS

    2009-07-01

    Full Text Available

    Foram determinados os teores de fibras alimentares (FDA, FDN, lignina e pectinas das folhas de brócolis e couve-flor e comparados aos teores encontrados nas tradicionais folhas de couve. Os materiais estudados foram cultivados no município de Ijaci MG, com o objetivo da utilização integral dessas hortaliças como fonte alternativa de fibras. As folhas foram submetidas a cocção por seis diferentes tempos (0, 2, 4, 6, 8 e 10 minutos. Acompanhando o comportamento das diversas frações da fibra no material úmido e após secagem. Os resultados mostraram que as folhas de couve-flor e brócolis superaram a couve comum, que apresentou teores superiores apenas na fração FDA do material seco. Os resultados revelaram que as folhas das hortaliças analisadas podem ser consideradas como boas fontes de fibras insolúveis, mas não contribuem significativamente com a porção solúvel.

  14. Causally nonseparable processes admitting a causal model

    International Nuclear Information System (INIS)

    Feix, Adrien; Araújo, Mateus; Brukner, Caslav

    2016-01-01

    A recent framework of quantum theory with no global causal order predicts the existence of ‘causally nonseparable’ processes. Some of these processes produce correlations incompatible with any causal order (they violate so-called ‘causal inequalities’ analogous to Bell inequalities ) while others do not (they admit a ‘causal model’ analogous to a local model ). Here we show for the first time that bipartite causally nonseparable processes with a causal model exist, and give evidence that they have no clear physical interpretation. We also provide an algorithm to generate processes of this kind and show that they have nonzero measure in the set of all processes. We demonstrate the existence of processes which stop violating causal inequalities but are still causally nonseparable when mixed with a certain amount of ‘white noise’. This is reminiscent of the behavior of Werner states in the context of entanglement and nonlocality. Finally, we provide numerical evidence for the existence of causally nonseparable processes which have a causal model even when extended with an entangled state shared among the parties. (paper)

  15. Reação de cultivares de batata a Streptomyces scabies, agente causal da sarna comum profunda Reaction of potato cultivars to Streptomyces scabies, causal agent of deep common scab

    Directory of Open Access Journals (Sweden)

    Ivan Herman Fischer

    2009-09-01

    Full Text Available Este trabalho visou caracterizar quanto a critérios morfológicos e fisiológicos isolados de Streptomyces causadores de sarna comum profunda em batata; avaliar o comportamento de cultivares em relação à doença e a variação na agressividade entre os isolados da bactéria. Os isolados de Streptomyces apresentaram coloração cinza em meio extrato de levedura e malte e cadeias de esporos espiraladas, produzidas sobre um micélio aéreo. Ocorreu produção de melanina em meio de tirosina-ágar e a utilização de oito fontes de carbono recomendadas, propriedades estas que correspondem às descritas para S. scabies. Batatas-semente sadias de seis cultivares foram plantadas em substrato infestado com seis isolados de S. scabies separadamente e as plantas cultivadas em vasos e ambiente aberto. A severidade da doença foi estimada com auxílio de uma escala diagramática e avaliou-se o rendimento de tubérculos (g/planta. As cvs. Mondial e Jaete Bintje foram as mais resistentes à sarna comum com severidade média nos dois experimentos de 10,5% e 14,0%, respectivamente, seguidas por Asterix (17,4%, Ágata (21,8%, Monalisa (23,0% e Cupido (23,3%. A agressividade dos isolados variou quantitativamente, com severidade maior para o isolado M4 (34,7% e menor para o isolado M1 (6,2%. Redução da produção de tubérculos foi verificada na cv. Jaete Bintje, no primeiro experimento, e quando as cultivares foram infectadas pelos isolados A1, M2 e M3, no primeiro experimento, e pelo isolado M4, no segundo experimento.This work aimed to characterize the isolates of Streptomyces, responsible for deep common scab symptoms in potato, according to morphological and physiological criteria; to evaluate the resistance of potato cultivars to the disease and the aggressiveness of bacterium isolates. The Streptomyces isolates presented gray coloration on yeast extract and malt medium and spiral spore chains, produced on aerial hyphae. Production of melanina occurred

  16. A set of haploid strains available for genetic studies of Saccharomyces cerevisiae flor yeasts.

    Science.gov (United States)

    Coi, Anna Lisa; Legras, Jean-Luc; Zara, Giacomo; Dequin, Sylvie; Budroni, Marilena

    2016-09-01

    Flor yeasts of Saccharomyces cerevisiae have been extensively studied for biofilm formation, however the lack of specific haploid model strains has limited the application of genetic approaches such as gene knockout, allelic replacement and Quantitative Trait Locus mapping for the deciphering of the molecular basis of velum formation under biological ageing. The aim of this work was to construct a set of flor isogenic haploid strains easy to manipulate genetically. The analysis of the allelic variations at 12 minisatellite loci of 174 Saccharomyces cerevisiae strains allowed identifying three flor parental strains with different phylogenic positions. These strains were characterized for sporulation efficiency, growth on galactose, adherence to polystyrene, agar invasion, growth on wine and ability to develop a biofilm. Interestingly, the inability to grow on galactose was found associated with a frameshift in GAL4 gene that seems peculiar of flor strains. From these wild flor strains, isogenic haploid strains were constructed by deleting HO gene with a loxP-KanMX-loxP cassette followed by the removal of the kanamycin cassette. Haploid strains obtained were characterized for their phenotypic and genetic properties and compared with the parental strains. Preliminary results showed that the haploid strains represent new tools for genetic studies and breeding programs on biofilm formation. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. L-histidine inhibits biofilm formation and FLO11-associated phenotypes in Saccharomyces cerevisiae flor yeasts.

    Science.gov (United States)

    Bou Zeidan, Marc; Zara, Giacomo; Viti, Carlo; Decorosi, Francesca; Mannazzu, Ilaria; Budroni, Marilena; Giovannetti, Luciana; Zara, Severino

    2014-01-01

    Flor yeasts of Saccharomyces cerevisiae have an innate diversity of Flo11p which codes for a highly hydrophobic and anionic cell-wall glycoprotein with a fundamental role in biofilm formation. In this study, 380 nitrogen compounds were administered to three S. cerevisiae flor strains handling Flo11p alleles with different expression levels. S. cerevisiae strain S288c was used as the reference strain as it cannot produce Flo11p. The flor strains generally metabolized amino acids and dipeptides as the sole nitrogen source, although with some exceptions regarding L-histidine and histidine containing dipeptides. L-histidine completely inhibited growth and its effect on viability was inversely related to Flo11p expression. Accordingly, L-histidine did not affect the viability of the Δflo11 and S288c strains. Also, L-histidine dramatically decreased air-liquid biofilm formation and adhesion to polystyrene of the flor yeasts with no effect on the transcription level of the Flo11p gene. Moreover, L-histidine modified the chitin and glycans content on the cell-wall of flor yeasts. These findings reveal a novel biological activity of L-histidine in controlling the multicellular behavior of yeasts [corrected].

  18. Controle alternativo de Colletotrichum acutatum agente causal da queda prematura dos frutos cítricos Alternative control of Colletotrichum acutatum, causal agent of postbloom fruit drop of citrus

    Directory of Open Access Journals (Sweden)

    Katia Cristina Kupper

    2009-12-01

    Full Text Available A queda prematura dos frutos cítricos (QPFC, causada por Colletotrichum acutatum, dados os grandes prejuízos que têm causado aos produtores, constitui-se numa doença de grande importância econômica. O controle da doença é feito predominantemente mediante uso de fungicidas, que eleva o custo de produção e afeta negativamente o meio ambiente. Diante disso, este trabalho teve por objetivo buscar um método alternativo de controle da QPFC, mediante o uso de agentes de biocontrole ou de biofertilizantes. Diferentes concentrações de biofertilizantes (originários de duas fontes distintas e denominados de Bio1 e Bio 2; três isolados de Bacillus subtilis (ACB-69; 72 e 77 e três isolados de Trichoderma spp. (ACB-14; 37 e 39 foram testados, isoladamente ou em combinação, sob condições de laboratório, quanto à capacidade inibitória da germinação de conídios de C. acutatum. Estudaram-se, ainda, a produção de metabólitos termoestáveis por B. subtilis e o efeito sobre a germinação do patógeno. Quinze isolados de B. subtilis foram testados quanto à capacidade de prevenir a infecção por C. acutatum em flores destacadas de lima- ácida 'Tahiti' e, no campo, foram instalados dois experimentos, visando a testar ACBs e biofertilizantes no controle da doença. Verificou-se que o isolado ACB-72 (B. subtilis e ACB-37 (T. pseudokoningii foram os que mais inibiram a germinação do patógeno. Quanto à produção de metabólitos termoestáveis, ACB-69 e 77 foram os mais eficientes em produzir substâncias antifúngicas, e em quantidades suficientes para inibirem a germinação do patógeno. A mistura dos quatro isolados de Bacillus (ACBs: 69; 72; 77 e AP3 foi o que apresentou maior porcentagem de inibição (73%. Os biofertilizantes (Bio1 e Bio2, em concentrações acima de 10% e, quando em associação com isolados de Trichoderma spp., promoveram maiores inibições na germinação de C. acutatum. Em testes com flores destacadas

  19. Descriptores para la caracterización y registro de variedades cubanas de Flor de Jamaica (Hibiscus sabdariffa L.)

    OpenAIRE

    González Cepero, María C

    2014-01-01

    Se describen las principales características de la Flor de Jamaica (Hibiscus sabdariffa L.) así como el momento y la forma de evaluación The main characteristics of the Flor de Jamaica (Hibiscus sabdariffa L.) are described as well as the evaluation period and evaluation way

  20. Causal reasoning in physics

    CERN Document Server

    Frisch, Mathias

    2014-01-01

    Much has been written on the role of causal notions and causal reasoning in the so-called 'special sciences' and in common sense. But does causal reasoning also play a role in physics? Mathias Frisch argues that, contrary to what influential philosophical arguments purport to show, the answer is yes. Time-asymmetric causal structures are as integral a part of the representational toolkit of physics as a theory's dynamical equations. Frisch develops his argument partly through a critique of anti-causal arguments and partly through a detailed examination of actual examples of causal notions in physics, including causal principles invoked in linear response theory and in representations of radiation phenomena. Offering a new perspective on the nature of scientific theories and causal reasoning, this book will be of interest to professional philosophers, graduate students, and anyone interested in the role of causal thinking in science.

  1. Theories of Causality

    Science.gov (United States)

    Jones, Robert

    2010-03-01

    There are a wide range of views on causality. To some (e.g. Karl Popper) causality is superfluous. Bertrand Russell said ``In advanced science the word cause never occurs. Causality is a relic of a bygone age.'' At the other extreme Rafael Sorkin and L. Bombelli suggest that space and time do not exist but are only an approximation to a reality that is simply a discrete ordered set, a ``causal set.'' For them causality IS reality. Others, like Judea Pearl and Nancy Cartwright are seaking to build a complex fundamental theory of causality (Causality, Cambridge Univ. Press, 2000) Or perhaps a theory of causality is simply the theory of functions. This is more or less my take on causality.

  2. Physiological potential of cauliflower seeds Potencial fisiológico de sementes de couve-flor

    Directory of Open Access Journals (Sweden)

    Ana Lúcia Pereira Kikuti

    2008-01-01

    Full Text Available The assessment of seed physiological performance is essential to provide consistent information to compose quality control programs conducted by seed companies and allow prompt decisions to reduce post-harvest and commercialization problems. This research was carried to evaluate the efficiency of different procedures to determine cauliflower seed vigor. Six lots of the cultivar Sharon were initially characterized by germination and seedling emergence, and subsequently subjected to traditional and saturated salt accelerated aging, controlled deterioration, electrical conductivity, and potassium leachate tests, in two evaluation times. The traditional accelerated aging (41ºC/48 h, the saturated salt procedure (45ºC/72 h, the controlled deterioration (moisture content adjusted to 20% or 22% and aging at 45ºC/24 h, the electrical conductivity (50 seeds/75 mL water and evaluation after 4 h and the potassium leakage (25 seeds/50 mL of water and evaluation after 30 min laboratory tests are sensitive to detect differences in the physiological potential of cauliflower seeds. However, those results did not relate to the percentage seedling emergence in greenhouse controlled conditions, as a consequence of the favorable conditions for emergence. However, the differences identified in the tests may be related to the ability of seed lots to perform in less favorable environments.A eficiência da determinação do potencial fisiológico de lotes de sementes é essencial para a obtenção de informações consistentes, permitindo a composição de programas de controle de qualidade de sementes e a obtenção de informações consistentes para a redução de problemas pós-colheita e durante a comercialização. O objetivo desta pesquisa foi comparar a eficiência de diferentes procedimentos para a determinação do vigor de sementes de couve-flor. Para tanto, foram utilizados seis lotes do cultivar Sharon, caracterizados inicialmente pelos testes de germina

  3. Florística em um hectare de cerrado stricto sensu na ARIE - cerrado Pé-de-Gigante, Santa Rita do Passa Quatro, SP

    Directory of Open Access Journals (Sweden)

    Weiser Veridiana de Lara

    2001-01-01

    Full Text Available Foi realizado um levantamento florístico em um ha de cerrado stricto sensu, na parte norte da ARIE - Cerrado Pé-de-Gigante, Santa Rita do Passa Quatro, São Paulo. Foram coletados 428 espécimes em fase reprodutiva, em vinte e cinco excursões de coleta, durante o período de novembro de 1996 a abril de 1998. A listagem florística obtida apresenta 141 espécies, distribuídas em 109 gêneros e 49 famílias. As famílias mais representativas foram: Leguminosae, Asteraceae, Malpighiaceae e Myrtaceae. A floração e frutificação das espécies foram maiores no período chuvoso. Espécies zoocóricas (61 predominaram, seguidas pelas anemocóricas (46 e autocóricas (34. Analisou-se a flora como um todo e seus componentes herbáceo-subarbustivo e arbustivo-arbóreo, separadamente.

  4. Causality in Science

    Directory of Open Access Journals (Sweden)

    Cristina Puente Águeda

    2011-10-01

    Full Text Available Causality is a fundamental notion in every field of science. Since the times of Aristotle, causal relationships have been a matter of study as a way to generate knowledge and provide for explanations. In this paper I review the notion of causality through different scientific areas such as physics, biology, engineering, etc. In the scientific area, causality is usually seen as a precise relation: the same cause provokes always the same effect. But in the everyday world, the links between cause and effect are frequently imprecise or imperfect in nature. Fuzzy logic offers an adequate framework for dealing with imperfect causality, so a few notions of fuzzy causality are introduced.

  5. Composição Florística do estrato arbóreo da Floresta Estacional Semidecidual na Planície Aluvial do rio Doce, Linhares, ES, Brasil Floristic composition of the tree layer in Atlantic forest on the rio Doce alluvial floodplain, Espírito Santo State, Brazil

    Directory of Open Access Journals (Sweden)

    Samir Gonçalves Rolim

    2006-09-01

    Full Text Available Este trabalho apresenta a flora de espécies arbóreas e palmeiras na floresta estacional semidecidual na planície aluvial do rio Doce, uma área de cerca de 20.000 ha, a partir de Linhares (ES até próximo à foz no oceano atlântico. Foram determinadas 408 espécies (27 classificadas em gênero e 59 famílias, entre arbóreas e palmeiras. Por meio da análise de agrupamento, foi evidenciado que a floresta do rio Doce é muito semelhante floristicamente à floresta estacional dos tabuleiros terciários, que estas se agrupam com as florestas estacionais do rio Doce em MG e que, por sua vez, todas estas se agrupam com as florestas ombrófilas do sul da Bahia, sendo o conjunto nitidamente separado das outras formações ombrófilas costeiras. Foram encontradas dezenas de espécies deocorrência restrita ou pouco frequentes em levantamentos na floresta atlântica, enfatizando a importância da área para conservação da biodiversidade. Pelo fato das matas de cacau na região abrangerem mais de 80% dessa área, sugere-se a delimitação de uma Área de Proteção Ambiental, que permita conciliar o cultivo do cacau com a proteção da biodiversidade.The tree and palm flora was studied in the Atlantic forest of the rio Doce alluvial floodplain, in a 20,000ha area, between Linhares (Espírito Santo State and the Atlantic Ocean. The floristic survey recorded 408 species and 59 families. Floristic composition was compared to other forests of São Paulo, Minas Gerais, Bahia and Rio de Janeiro states using cluster analysis. The forest flora of the study area was most similar to that of forests in Espírito Santo, Minas Gerais, and Bahia. Dozens of species in the study area are restricted and rare in Atlantic forest; this area deserves special attention for biodiversity conservation. The Brazilian government should pay heed to the biological importance of this area and declare it an Environmental Protection Area, a type of conservation unit where

  6. Composição florística e fitossociologia do cerrado sentido restrito no município de Água Boa - MT

    Directory of Open Access Journals (Sweden)

    Felfili Jeanine Maria

    2002-01-01

    Full Text Available O estudo foi conduzido no município de Água Boa , no Vale do Araguaia, área de ecótono entre o Cerrado e Amazônia, que apresenta um complexo vegetacional com o predomínio do cerrado. O objetivo deste trabalho foi estudar a composição florística e a fitossociologia do cerrado sentido restrito na região. Foram alocadas dez parcelas de 20x50m (1000m². Entraram na amostragem todos os indivíduos lenhosos com diâmetro no nível do solo igual ou superior a 5cm. Além da amostragem com identificação in loco das espécies, foram efetuadas incursões de coleta em áreas próximas, para ampliar o levantamento da composição florística. Foram encontradas 34 famílias botânicas, contendo 60 gêneros e 80 espécies. A família Leguminosae apresentou o maior número de espécies (10, seguida por Myrtaceae (7, Vochysiaceae (6 e Malpighiaceae (5. Outras 19 famílias foram representadas por uma única espécie. As espécies com maior Índice de Valor de Importância foram Curatella americana L., Qualea parviflora Mart., Callisthene fasciculata Mart., Mezilaurus crassiramea (Meiss Taub. e Byrsonima crassa Nied. Treze espécies estiveram representadas por um único indivíduo. A densidade foi de 995 indivíduos/ha e a área basal de 7,5 m² /ha. O índice de Shannon encontrado (H' foi de 3,69, evidenciando a alta diversidade da área.

  7. Influência da cobertura e do solo na composição florística do sub-bosque em uma floresta estacional semidecidual em Viçosa, MG, Brasil Cover and soil influence at understory of a Seasonal Tropical Forest, Minas Gerais State, Brazil

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    João Augusto Alves Meira-Neto

    2005-09-01

    Full Text Available A relação ecológica planta-luz tem sido estudada desde o início do século XX. As análises da relação da luminosidade ao nível das comunidades florestais têm se valido de medições indiretas por meio de índices de cobertura, mas sem a aplicação da fotogrametria para estimar essa cobertura. Este trabalho foi idealizado para utilizar fotogrametria do dossel, tornando-a aplicável ao estudo da luminosidade no sub-bosque herbáceo-arbustivo. Teve como objetivos estabelecer a relação existente entre espécies do estrato herbáceo-arbustivo e a cobertura do dossel e averiguar a existência de correlações entre espécies, luminosidade e variáveis pedológicas. Para tanto, foram tiradas fotografias em preto e branco nos períodos seco e chuvoso, em 100 (1 m×1 m parcelas aplicadas para a amostragem da vegetação herbácea. Foram colhidas amostras de solo em cada parcela. A partir dos valores médios das medidas de cobertura estimada pelas fotografias dos períodos seco e chuvoso calculou-se o valor médio de cobertura para cada espécie amostrada. Por meio do teste "t" student e da Análise de Correspondência Canônica foram determinadas as relações entre as espécies, a luminosidade e as variáveis pedológicas no estrato herbáceo-arbustivo. A cobertura não foi significativamente diferente nas épocas seca e na chuvosa. Apenas três espécies, Heisteria silviani, Calathea brasiliensis e Psychotria conjugens, tiveram médias de cobertura significativamente maiores que a média amostral e outras três, Olyra micrantha, Lacistema pubescens e Pteris denticulata, tiveram médias menores. As distribuições de parcelas pelos valores de cobertura, de tamanho de clareiras e pelo número de clareiras mostraram-se similares às distribuições encontradas na literatura para outras florestas tropicais e, portanto, o método da fotogrametria revelou-se adequado para a avaliação da cobertura. Verificou-se que os teores de cálcio, magn

  8. Fatores determinantes para as expectativas de primigestas acerca da via de parto Primigravid expectations about the delivery method and the causal factors for their choice

    Directory of Open Access Journals (Sweden)

    Ricardo Porto Tedesco

    2004-12-01

    Full Text Available OBJETIVO: conhecer as expectativas de primigestas com relação à via de parto, bem como os motivos de sua escolha, procurando melhorar a qualidade do relacionamento médico-paciente. MÉTODOS: foi realizado estudo do tipo qualitativo por meio da análise do sujeito coletivo, incluindo primigestas atendidas de setembro a novembro de 2003 nos pronto-socorros dos serviços da Faculdade de Medicina de Jundiaí. Foi aplicado questionário especialmente elaborado para responder aos objetivos propostos pela pesquisa o questionário é baseado nas dúvidas apresentadas por pacientes que freqüentaram o serviço meses antes da elaboração do projeto. O consentimento livre e esclarecido, assinado pela gestante e por um dos pesquisadores responsáveis. Foi obtido para fins de padronização da amostra a seleção das pacientes seguiu critérios de inclusão: idade maior que 16 anos, primigestas, que estivessem recebendo assistência pré-natal e consentimento pós-informado lido e esclarecido. Foram considerados critérios de exclusão pacientes mentalmente incapacitadas e gestantes de alto risco com doenças que pudessem interferir na escolha da paciente. RESULTADOS: a população estudada teve como perfil mais prevalente mulheres com mais de 21 anos, brancas, casadas, com segundo grau completo e que estavam no terceiro trimestre da gestação. A via de parto de preferência da maioria das mulheres (90% foi o parto vaginal normal, sendo que as principais justificativas foram: a praticidade para sua realização (94% e o medo do sofrimento e dor no pós-parto causados pela cesárea. Encontramos relação entre a preferência pelo parto vaginal com mulheres de maior idade, casadas, não havendo diferença significativa entre as raças. CONCLUSÃO: estes resultados nos mostram enorme contraste entre a preferência das mulheres e os altos índices de cesárea no Brasil. Concluímos que deve haver falha de informação, falta de diálogo entre os

  9. Reasoning with Causal Cycles

    Science.gov (United States)

    Rehder, Bob

    2017-01-01

    This article assesses how people reason with categories whose features are related in causal cycles. Whereas models based on causal graphical models (CGMs) have enjoyed success modeling category-based judgments as well as a number of other cognitive phenomena, CGMs are only able to represent causal structures that are acyclic. A number of new…

  10. Ethanol-Independent Biofilm Formation by a Flor Wine Yeast Strain of Saccharomyces cerevisiae▿

    Science.gov (United States)

    Zara, Severino; Gross, Michael K.; Zara, Giacomo; Budroni, Marilena; Bakalinsky, Alan T.

    2010-01-01

    Flor strains of Saccharomyces cerevisiae form a biofilm on the surface of wine at the end of fermentation, when sugar is depleted and growth on ethanol becomes dependent on oxygen. Here, we report greater biofilm formation on glycerol and ethyl acetate and inconsistent formation on succinic, lactic, and acetic acids. PMID:20435772

  11. Ethanol-independent biofilm formation by a flor wine yeast strain of Saccharomyces cerevisiae.

    Science.gov (United States)

    Zara, Severino; Gross, Michael K; Zara, Giacomo; Budroni, Marilena; Bakalinsky, Alan T

    2010-06-01

    Flor strains of Saccharomyces cerevisiae form a biofilm on the surface of wine at the end of fermentation, when sugar is depleted and growth on ethanol becomes dependent on oxygen. Here, we report greater biofilm formation on glycerol and ethyl acetate and inconsistent formation on succinic, lactic, and acetic acids.

  12. Composição lignocelulósica e isótopica da vegetação e da matéria orgânica do solo de uma turfeira tropical: I - composição florística, fitomassa e acúmulo de carbono Lignocellulosic and isotopic composition of vegetation and soil organic matter of a tropical peat: I floristic composition, biomass and carbon stock

    Directory of Open Access Journals (Sweden)

    Vinicius Evangelista Silva

    2013-02-01

    Full Text Available A matéria orgânica do solo (MOS é um dos grandes reservatórios de carbono (C da Terra e constitui um dos principais componentes do ciclo do C. Turfeiras, ambientes acumuladores de MOS, são produto da decomposição de vegetais, que se desenvolvem e se acumulam em ambientes saturados com água, sendo o estádio inicial da sequência de carbonificação. A fitomassa participa de forma marcante no ciclo global do C, armazenando em torno de 85 % de todo o C terrestre acima do solo. O tecido vegetal é composto principalmente por lignina, celulose e hemicelulose, constituindo até 85 % da biomassa seca. As plantas discriminam C de forma diferenciada, em razão de seu ciclo fotossintético (C3, C4 e CAM. As turfeiras da Serra do Espinhaço Meridional (SdEM-MG são colonizadas por vegetação de Campo Limpo Úmido (CLU e de Floresta Estacional Semidecidual (FES, onde ocorrem espécies dos ciclos fotossintéticos C3 e C4. Este trabalho objetivou avaliar a contribuição dessas duas fitofisionomias para o acúmulo de MOS, por meio da avaliação da fitomassa e da composição lignocelulósica e isotópica da vegetação e da MOS. A turfeira estudada localiza-se na SdEM e ocupa 81,75 ha. Para a estimativa da fitomassa do CLU e da FES, foram marcadas três parcelas de 0,5 x 0,5 m em cada fitofisionomia, onde todos os indivíduos da parcela foram cortados e armazenados. Para as análises isotópicas e lignocelulósicas da vegetação, identificaram-se as espécies dominantes em cada fitofisionomia. Amostras de solo foram coletadas em três locais representativos sob cada fitofisionomia, a cada 5 cm de profundidade, até 50 cm. Foram extraídas a celulose e a lignina das folhas das 15 espécies dominantes e das 60 amostras de turfeira para quantificação e determinação dos valores de δ13C e δ15N. Para datação da MOS, o 14C foi determinado em três profundidades, sob o CLU e a FES. A produção da fitomassa da FES foi muito superior à produ

  13. Genomic signatures of adaptation to wine biological ageing conditions in biofilm-forming flor yeasts.

    Science.gov (United States)

    Coi, A L; Bigey, F; Mallet, S; Marsit, S; Zara, G; Gladieux, P; Galeote, V; Budroni, M; Dequin, S; Legras, J L

    2017-04-01

    The molecular and evolutionary processes underlying fungal domestication remain largely unknown despite the importance of fungi to bioindustry and for comparative adaptation genomics in eukaryotes. Wine fermentation and biological ageing are performed by strains of S. cerevisiae with, respectively, pelagic fermentative growth on glucose and biofilm aerobic growth utilizing ethanol. Here, we use environmental samples of wine and flor yeasts to investigate the genomic basis of yeast adaptation to contrasted anthropogenic environments. Phylogenetic inference and population structure analysis based on single nucleotide polymorphisms revealed a group of flor yeasts separated from wine yeasts. A combination of methods revealed several highly differentiated regions between wine and flor yeasts, and analyses using codon-substitution models for detecting molecular adaptation identified sites under positive selection in the high-affinity transporter gene ZRT1. The cross-population composite likelihood ratio revealed selective sweeps at three regions, including in the hexose transporter gene HXT7, the yapsin gene YPS6 and the membrane protein coding gene MTS27. Our analyses also revealed that the biological ageing environment has led to the accumulation of numerous mutations in proteins from several networks, including Flo11 regulation and divalent metal transport. Together, our findings suggest that the tuning of FLO11 expression and zinc transport networks are a distinctive feature of the genetic changes underlying the domestication of flor yeasts. Our study highlights the multiplicity of genomic changes underlying yeast adaptation to man-made habitats and reveals that flor/wine yeast lineage can serve as a useful model for studying the genomics of adaptive divergence. © 2017 John Wiley & Sons Ltd.

  14. Análise da florística e estrutura de floresta primária visando a seleção de espécies-chave, através de análise multivariada, para a restauração de áreas mineradas em unidades de conservação

    Directory of Open Access Journals (Sweden)

    Rafael Paiva Salomão

    2012-12-01

    Full Text Available Na Amazônia, vários empreendimentos minerários estão situados em unidades de conservação. A restauração ecológica após a lavra do minério abrange vários atributos. Entre esses, destaca-se a necessidade de o ecossistema restaurado conter um conjunto de espécies-chave de ocorrência no ecossistema de referência e, dessa forma, proporcionar estrutura apropriada de comunidade, além de ser constituído do maior número possível de espécies nativas. Objetivou-se, neste trabalho, analisar um índice fitossociológico e socioeconômico (IFSE, obtido por técnicas de análise multivariada. O modelo envolveu seis variáveis quantitativas (abundância, frequência, dominância, biomassa, valor comercial da madeira e quantidade de produtos florestais não madeireiros e igual número de variáveis qualitativas. Em uma área de floresta ombrófila de 1.321 ha, foram amostradas 315 parcelas de 0,25 ha, em que todos os indivíduos com DAP > 10 cm foram identificados e mensurados. Foram registrados 36.298 indivíduos, distribuídos em 898 espécies, abrangendo 62 famílias. As espécies foram ranqueadas através do índice proposto em três categorias de prioridade fitossociológica e socioeconômica (alta, média e baixa. A adequação da análise fatorial foi determinada pelos testes de Bartlett e KMO. O teste de Bartlett avaliou a significância geral da matriz de correlação a 1% de probabilidade. O teste KMO indicou que as variáveis estão correlacionadas, e o modelo fatorial apresentou nível muito bom de adequação aos dados. O uso de análise multivariada foi estatisticamente validado para o emprego do IFSE. Entre as 898 espécies analisadas, 25 foram selecionadas como prioritárias (categorias alta e média, sendo reconhecidas como espécies-chave. Foi estimada a densidade de plantio dessas espécies para recuperação de áreas mineradas na Amazônia, com condições biológicas e ambientais semelhantes às relatadas neste estudo. A

  15. Efeito inibitório de extratos vegetais sobre Colletotrichum gloeosporioides - agente causal da podridão de frutos de mamoeiro

    Directory of Open Access Journals (Sweden)

    Ribeiro Luiz Fernando

    1999-01-01

    Full Text Available Extratos aquosos foram obtidos a partir de bulbilhos de alho, folhas de hortelã e mamona e frutos de pimenta. Após a incorporação destes extratos em BDA, obtendo-se concentrações de 100, 200, 500, 1000, 5000 e 10000 ppm, foi avaliado o crescimento e a produção de conídios de um isolado de Colletotrichum gloeosporioides, agente de podridão em frutos de mamoeiro. Os resultados demonstraram o efeito inibitório dos diferentes extratos a partir da concentração de 200 ppm. O extrato de alho inibiu o crescimento micelial, em porcentagens variáveis de 5,3 a 67,6%, porém não atuou de modo expressivo sobre a produção de conídios. Em contraposição, os extratos de hortelã, mamona e pimenta promoveram inibição menos acentuada do crescimento de micélio, porém reduziram drasticamente a produção de conídios em níveis variáveis de 41 a 84%, de acordo com as concentrações crescentes dos mesmos. As propriedades fungitóxicas detectadas nos extratos utilizados no ensaio evidenciaram o uso potencial dos mesmos como alternativa aos métodos físicos e químicos convencionalmente usados para o controle da doença.

  16. Causal imprinting in causal structure learning.

    Science.gov (United States)

    Taylor, Eric G; Ahn, Woo-Kyoung

    2012-11-01

    Suppose one observes a correlation between two events, B and C, and infers that B causes C. Later one discovers that event A explains away the correlation between B and C. Normatively, one should now dismiss or weaken the belief that B causes C. Nonetheless, participants in the current study who observed a positive contingency between B and C followed by evidence that B and C were independent given A, persisted in believing that B causes C. The authors term this difficulty in revising initially learned causal structures "causal imprinting." Throughout four experiments, causal imprinting was obtained using multiple dependent measures and control conditions. A Bayesian analysis showed that causal imprinting may be normative under some conditions, but causal imprinting also occurred in the current study when it was clearly non-normative. It is suggested that causal imprinting occurs due to the influence of prior knowledge on how reasoners interpret later evidence. Consistent with this view, when participants first viewed the evidence showing that B and C are independent given A, later evidence with only B and C did not lead to the belief that B causes C. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Repeated causal decision making.

    Science.gov (United States)

    Hagmayer, York; Meder, Björn

    2013-01-01

    Many of our decisions refer to actions that have a causal impact on the external environment. Such actions may not only allow for the mere learning of expected values or utilities but also for acquiring knowledge about the causal structure of our world. We used a repeated decision-making paradigm to examine what kind of knowledge people acquire in such situations and how they use their knowledge to adapt to changes in the decision context. Our studies show that decision makers' behavior is strongly contingent on their causal beliefs and that people exploit their causal knowledge to assess the consequences of changes in the decision problem. A high consistency between hypotheses about causal structure, causally expected values, and actual choices was observed. The experiments show that (a) existing causal hypotheses guide the interpretation of decision feedback, (b) consequences of decisions are used to revise existing causal beliefs, and (c) decision makers use the experienced feedback to induce a causal model of the choice situation even when they have no initial causal hypotheses, which (d) enables them to adapt their choices to changes of the decision problem. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

  18. Análise florística e estrutural de sistemas silviagrícolas em Tomé-Açu, Pará

    Directory of Open Access Journals (Sweden)

    Édson Luis Bolfe

    2011-10-01

    Full Text Available O objetivo deste trabalho foi analisar a composição florística e estrutural de sistemas silviagrícolas em Tomé-Açu, Pará. Os dados dendrométricos foram obtidos por inventário em 40 parcelas amostrais, com três unidades cada uma, no total de 120 unidades de 10x10 m. Foi inventariada a média de 1.424,3 indivíduos por hectare, pertencentes a 27 famílias e a 54 espécies. Tendo-se considerado a variabilidade dos estágios vegetativos, os diferentes sistemas silviagrícolas (SAF foram divididos em quatro classes hierárquicas: SAF 1, SAF 2, SAF 3, e SAF 4, para estabelecer um sistema de classificação passível de ser utilizado em outras avaliações de campo e em classificações digitais por meio do sensoriamento remoto. Espécies observadas em outros sistemas da região amazônica também foram relevantes para este estudo, especialmente Theobroma cacao, T. grandiflorum e Euterpe oleracea que, juntas, apresentaram médias de frequência relativa de 51%, densidade relativa de 69,2%, dominância relativa de 50,1% e índice de valor de importância de 56,8%. Os dados médios de diversidade florística, abundância, área basal e valor de importância indicam os sistemas silviagrícolas da região de Tomé-Açu como sistemas de produção com potencial econômico e ambiental, se adotado manejo adequado e racional.

  19. Piperaceae em um fragmento de floresta atlântica da Serra da Mantiqueira, Minas Gerais, Brasil

    OpenAIRE

    Monteiro, Daniele

    2013-01-01

    A Serra Negra localiza-se em Minas Gerais (21°58'24"S e 43°53'15"W), entre as Serras do Ibitipoca e o Maciço do Itatiaia, abrangendo uma área da Serra da Mantiqueira considerada prioritária para a conservação e investigação científica. Com o objetivo de ampliar o conhecimento florístico da região, foi realizado o tratamento florístico das Piperaceae ocorrentes. Foram registradas 34 espécies da família, a grande maioria em formações florestais, incluindo cânions. Contribuíram para a identifica...

  20. O aumento da lucratividade expande a acumulação de capital? Uma análise de causalidade de Granger para países da OCDE Does increasing profitability rise capital accumulation? A Granger causality analysis on OECD countries

    Directory of Open Access Journals (Sweden)

    Adalmir Marquetti

    2009-12-01

    Full Text Available O objetivo deste trabalho é testar a hipótese clássico-marxiana de ligação causal entre a taxa de lucro e a taxa de acumulação de capital para um conjunto de 20 países da OCDE. A metodologia utilizada baseia-se no procedimento proposto por Toda e Yamamoto (1995 para testar a hipótese de não causalidade de Granger. A especificação de teste empregada, derivada a partir da equação de Cambridge, envolve três variáveis: a taxa de lucro, a taxa de acumulação e a taxa de investimento. A consideração da variável investimento permite comparações entre as tradições clássico-marxiana e pós-keynesianas. Os resultados para a Austrália, a Dinamarca, os eua, a Finlândia e a Irlanda são consistentes com a concepção clássico-marxiana. Por outro lado, os resultados para o Canadá, a Coreia do Sul, a Grécia e a Suécia são parcialmente consistentes com a tradição pós-keynesiana.The purpose of this paper is to test the classical-Marxian hypothesis of causal linkages between profit rate and the accumulation of capital for a dataset of 20 OECD countries. The procedure proposed by Toda and Yamamoto (1995 to test for the Granger non-causality hypotheses is employed in the statistical procedure. The test specification, derived from the Cambridge equation, involve three variables: profit rate, accumulation of capital and investment rate. The consideration of the investment rate allows a comparison between the classical-Marxian and the post-Keynesian traditions. For the cases of Australia, Denmark, usa, Finland and Ireland, the results provide empirical support for the classical-Marxian conception. On the other hand, in the cases of Canada, South Korea, Greece and Sweden, the results support the post-Keynesian tradition.

  1. Composição florística do componente arbustivo-arbóreo em dois trechos de floresta estacional semidecidual na Mata do Paraíso, Viçosa, MG

    Directory of Open Access Journals (Sweden)

    Sheila Isabel do Carmo Pinto

    2013-09-01

    Full Text Available É grande a demanda por estudos ecológicos em florestas que possam embasar trabalhos de recuperação e conservação da biodiversidade. Entre esses estudos, primordialmente está o levantamento da flora. Nesse sentido, realizou-se o estudo das variações florísticas do componente arbustivo-arbóreo em dois trechos de Floresta Estacional Semidecidual, floresta inicial e floresta madura, situados na Reserva Florestal Mata do Paraíso, em Viçosa, Minas Gerais. As espécies arbóreo-arbustivas foram amostradas dentro de 20 parcelas de 10 x 30 m, 10 parcelas em cada trecho de floresta, sendo considerados apenas os indivíduos com diâmetro a 1,30 m do solo (DAP  4,8 cm. Na floresta inicial foram amostradas 55 espécies pertencentes a 47 gêneros e 27 famílias. A família com maior riqueza florística foi Fabaceae, com 10 espécies (18%, seguida de Euphorbiaceae (cinco espécies; 9%, Annonaceae, Lauraceae, Meliaceae e Salicaceae (três espécies; 6%. Na floresta madura foram amostradas 78 espécies distribuídas em 62 gêneros e 31 famílias. A família com maior riqueza florística foi Fabaceae, com 13 espécies (17%, seguida de Lauraceae e Myrtaceae (seis espécies; 8%, Euphorbiaceae, Sapindaceae e Salicaceae (cinco espécies; 6%, Annonaceae e Meliaceae (quatro espécies, 5%, Rubiaceae e Moraceae (três espécies; 4%. O grupo ecológico que mais se destacou nos dois trechos de floresta foi o das secundárias iniciais, seguido pelas secundárias tardias na floresta madura e pelas pioneiras na floresta inicial. A variabilidade na composição florística e na proporção de espécies em cada grupo ecológico foi resultante das variações na intensidade da ação antrópica nestas florestas e do tempo de regeneração florestal.

  2. Phytophthora palmivora, agente da podridão de raiz e frutos de mamoeiro no Estado de Alagoas Phytophthora palmivora, causal agent of root and fruit rots of papaya in the State of Alagoas, Brazil

    Directory of Open Access Journals (Sweden)

    Juliana Paiva Carnaúba

    2006-04-01

    Full Text Available O mamoeiro (Carica papaya é uma das mais importantes fruteiras tropicais, e seus frutos contribuem com uma produção de 1,65 milhão de toneladas por ano para o Brasil. Um isolado de Phytophthora sp. obtido de frutos de mamoeiro da cultivar Havaí, em Alagoas, foi caracterizado morfologicamente e sua patogenicidade foi confirmada em frutos e mudas deste hospedeiro. Em meio suco V-8, os esporangióforos apresentaram-se delgados, simples ou pouco ramificados, enquanto os esporângios se apresentaram ovóides a elipsóides, proeminentemente papilados e um pedicelo curto na porção basal, medindo em média 37,68 x 27,52 mm. Através das características apresentadas pelo isolado e os sintomas induzidos, o agente causal foi identificado como Phytophthora palmivora. Apesar de essa doença já ocorrer em outros estados, como Bahia, Espírito Santo, São Paulo, Pernambuco e Pará, este é o primeiro relato de Phytophthora palmivora em mamoeiro no Estado de Alagoas.The papaya (Carica papaya is one of the most important tropical fruit crops and its fruit contribute with a production of 1.65 millions tons/year in Brazil. An isolated of Phytophthora sp. gotten from papaya fruits cv. Hawaii, in the state of Alagoas, was characterized morphologically and its pathogenicity to this fruits and seedling was confirmed. In a V-8 medium, the sporangiophores presented to be slim, simple or little ramified, while the sporangia presented ovoid to ellipsoid, prominently papillae and one short pedicel in the basal portion, measuring in average 37,68 x 27,52 (m. Through the characteristics presented by the isolated and the induced symptoms, the causal agent was identified as Phytophthora palmivora. Despite of this disease already occurring in other states like in Bahia, Espirito Santo, São Paulo, Pernambuco and Pará, this is the first report of Phytophthora palmivora on papaya in the state of Alagoas, Brazil.

  3. Composição florísitica e fitossociologia de uma área de caatinga em Contendas do Sincorá, Bahia, microrregião homogênea da Chapada Diamantina Floristic and fitosociological survey of a caatinga area at "Contendas do Sincorá", Bahia State, a homogeneous microregion of the Chapada Diamantina

    Directory of Open Access Journals (Sweden)

    Paulo César Fernandes Lima

    1998-01-01

    Full Text Available Objetivou-se levantar a cobertura vegetal de 11.034ha da Fazenda Extrema-Lapinha, 295 a 380m de altitude (13º46' a 14ºS e 41º3' a 41º10'W, Contendas do Sincorá, BA, na Chapada Diamantina. O clima é do tipo BSwh', estépico, semi-árido quente, com precipitação anual de 500-700mm, período chuvoso de novembro a janeiro, temperatura média de 23ºC e umidade relativa de 60-80%. Predominam os solos Podzólicos Vermelho-Amarelo Equivalente Eutrófico e solos Litólicos Eutróficos, em relevo levemente ondulado. Foram distribuídas aleatoriamente 100 parcelas de 20x5m, sendo inventariadas as plantas com DAP > a 5cm. Foram encontrados 2.897 indivíduos abrangendo 71 espécies, 51 gêneros e 23 famílias botânicas, não sendo identificados 3,59% dos mesmos. As famílias Euphorbiaceae (15,67%, Mimosaceae (13,80%, Bignoniaceae (12,35%, Caesalpiniaceae (7,14%, Boraginaceae (6,63%, Polygonaceae (6,63%, Anacardiaceae (6,04%, Burseraceae (4,93%, Apocynaceae (4,59% e Combretaceae (4,28% correspondem a 82,09% dos indivíduos inventariados. Para as classes de diâmetro inventariadas, as Cactaceae corresponderam a 0,48%, sugerindo ser esta vegetação de caatinga de caráter xerófilo pouco acentuado. As 10 espécies mais importantes, determinadas pelo índice de valor de importância, foram Commiphora leptophloeos (22,28, Croton zehntneri (19,39, Mimosa sp. (17,24, Tabebuia spongiosa (16,99, Myracrodruon urundeuva (15,38, Anadenanthera tnacrocarpa (14,25, Coccoloba termiflora (11,73, Caesalpinia sp. (11,17, Cordia sp. (10,79 e Tabebuia sp. (10,20.The aim of this work was to conduct a floristic and phytosociological survey on 11,034 hectares of the Extrema Lapinha Farm (13º46' to 14º S and 41º03' to 41º10' W, altitude from 295 to 380m, in the town of "Contendas do Sincorá", in Chapada Diamantina, Bahia State. The climate is of the BSwh' type, hot semi-arid, with an annual rainfall of 500-700mm, the rainy season being from November to January, with

  4. Repeated Causal Decision Making

    Science.gov (United States)

    Hagmayer, York; Meder, Bjorn

    2013-01-01

    Many of our decisions refer to actions that have a causal impact on the external environment. Such actions may not only allow for the mere learning of expected values or utilities but also for acquiring knowledge about the causal structure of our world. We used a repeated decision-making paradigm to examine what kind of knowledge people acquire in…

  5. Viscous causal cosmologies

    International Nuclear Information System (INIS)

    Novello, M.; Salim, J.M.; Torres, J.; Oliveira, H.P. de

    1989-01-01

    A set of spatially homogeneous and isotropic cosmological geometries generated by a class of non-perfect is investigated fluids. The irreversibility if this system is studied in the context of causal thermodynamics which provides a useful mechanism to conform to the non-violation of the causal principle. (author) [pt

  6. Causal Analysis After Haavelmo

    Science.gov (United States)

    Heckman, James; Pinto, Rodrigo

    2014-01-01

    Haavelmo's seminal 1943 and 1944 papers are the first rigorous treatment of causality. In them, he distinguished the definition of causal parameters from their identification. He showed that causal parameters are defined using hypothetical models that assign variation to some of the inputs determining outcomes while holding all other inputs fixed. He thus formalized and made operational Marshall's (1890) ceteris paribus analysis. We embed Haavelmo's framework into the recursive framework of Directed Acyclic Graphs (DAGs) used in one influential recent approach to causality (Pearl, 2000) and in the related literature on Bayesian nets (Lauritzen, 1996). We compare the simplicity of an analysis of causality based on Haavelmo's methodology with the complex and nonintuitive approach used in the causal literature of DAGs—the “do-calculus” of Pearl (2009). We discuss the severe limitations of DAGs and in particular of the do-calculus of Pearl in securing identification of economic models. We extend our framework to consider models for simultaneous causality, a central contribution of Haavelmo. In general cases, DAGs cannot be used to analyze models for simultaneous causality, but Haavelmo's approach naturally generalizes to cover them. PMID:25729123

  7. Causality in Classical Electrodynamics

    Science.gov (United States)

    Savage, Craig

    2012-01-01

    Causality in electrodynamics is a subject of some confusion, especially regarding the application of Faraday's law and the Ampere-Maxwell law. This has led to the suggestion that we should not teach students that electric and magnetic fields can cause each other, but rather focus on charges and currents as the causal agents. In this paper I argue…

  8. Study of the role of the covalently linked cell wall protein (Ccw14p) and yeast glycoprotein (Ygp1p) within biofilm formation in a flor yeast strain.

    Science.gov (United States)

    Moreno-García, J; Coi, A L; Zara, G; García-Martínez, T; Mauricio, J C; Budroni, M

    2018-03-01

    Flor yeasts are Saccharomyces cerevisiae strains noted by their ability to create a type of biofilm in the air-liquid interface of some wines, known as 'flor' or 'velum', for which certain proteins play an essential role. Following a proteomic study of a flor yeast strain, we deleted the CCW14 (covalently linked cell wall protein) and YGP1 (yeast glycoprotein) genes-codifying for two cell surface glycoproteins-in a haploid flor yeast strain and we reported that both influence the weight of the biofilm as well as cell adherence (CCW14).

  9. Casos de Ensino em Administração: Dona Flor: Desintermediar ou ser Desintermediada!

    Directory of Open Access Journals (Sweden)

    Aline Stange

    2012-07-01

    Full Text Available The Dona Flor teaching case portrays the moment in which Pedro Brasil, founder of an erotic product reseller for women through direct sales, was looking for ways to keep his business healthy and growing. One possibility was derived from the fact that consumers did not recognize specific brands ofproducts, since there were no large companies in the erotic products market. The channel structure of the company, however, hindered the exploitation of this opportunity. The case highlights the fragilityof the company’s relationship with suppliers and with catalog distributors. Students should therefore consider the disintermediation of both upstream and downstream links in the value chain and the implications of this decision for the business. Moreover, the case suggests the possibility that Dona Flor itself was in danger of being disintermediated, requiring the evaluation of strategies to mitigate this risk, which include the development of a private label. The goal is to enable students to sketch the path-to-market diagram, and, based on it, provide alternatives for the company, considering the advantages and disadvantages of each proposal. They should also realize the importance of the differential offered by Dona Flor and the limitations it imposes on the exploitation of different distribution channels.

  10. Air-liquid biofilm formation is dependent on ammonium depletion in a Saccharomyces cerevisiae flor strain.

    Science.gov (United States)

    Zara, Giacomo; Budroni, Marilena; Mannazzu, Ilaria; Zara, Severino

    2011-12-01

    Air-liquid biofilm formation appears to be an adaptive mechanism that promotes foraging of Saccharomyces cerevisiae flor strains in response to nutrient starvation. The FLO11 gene plays a central role in this phenotype as its expression allows yeast cells to rise to the liquid surface. Here, we investigated the role of ammonium depletion in air-liquid biofilm formation and FLO11 expression in a S. cerevisiae flor strain. The data obtained show that increasing ammonium concentrations from 0 to 450 m m reduce air-liquid biofilm in terms of biomass and velum formation and correlate with a reduction of FLO11 expression. Rapamycin inhibition of the TOR pathway and deletion of RAS2 gene significantly reduced biofilm formation and FLO11 expression. Taken together, these data suggest that ammonium depletion is a key factor in the induction of air-liquid biofilm formation and FLO11 expression in S. cerevisiae flor strains. Copyright © 2011 John Wiley & Sons, Ltd.

  11. Causality in Europeanization Research

    DEFF Research Database (Denmark)

    Lynggaard, Kennet

    2012-01-01

    to develop discursive institutional analytical frameworks and something that comes close to the formulation of hypothesis on the effects of European Union (EU) policies and institutions on domestic change. Even if these efforts so far do not necessarily amount to substantive theories or claims of causality......Discourse analysis as a methodology is perhaps not readily associated with substantive causality claims. At the same time the study of discourses is very much the study of conceptions of causal relations among a set, or sets, of agents. Within Europeanization research we have seen endeavours......, it suggests that discourse analysis and the study of causality are by no means opposites. The study of Europeanization discourses may even be seen as an essential step in the move towards claims of causality in Europeanization research. This chapter deals with the question of how we may move from the study...

  12. Agency, time and causality

    Directory of Open Access Journals (Sweden)

    Thomas eWidlok

    2014-11-01

    Full Text Available Cognitive Scientists interested in causal cognition increasingly search for evidence from non-WEIRD people but find only very few cross-cultural studies that specifically target causal cognition. This article suggests how information about causality can be retrieved from ethnographic monographs, specifically from ethnographies that discuss agency and concepts of time. Many apparent cultural differences with regard to causal cognition dissolve when cultural extensions of agency and personhood to non-humans are taken into account. At the same time considerable variability remains when we include notions of time, linearity and sequence. The article focuses on ethnographic case studies from Africa but provides a more general perspective on the role of ethnography in research on the diversity and universality of causal cognition.

  13. Non-Causal Computation

    Directory of Open Access Journals (Sweden)

    Ämin Baumeler

    2017-07-01

    Full Text Available Computation models such as circuits describe sequences of computation steps that are carried out one after the other. In other words, algorithm design is traditionally subject to the restriction imposed by a fixed causal order. We address a novel computing paradigm beyond quantum computing, replacing this assumption by mere logical consistency: We study non-causal circuits, where a fixed time structure within a gate is locally assumed whilst the global causal structure between the gates is dropped. We present examples of logically consistent non-causal circuits outperforming all causal ones; they imply that suppressing loops entirely is more restrictive than just avoiding the contradictions they can give rise to. That fact is already known for correlations as well as for communication, and we here extend it to computation.

  14. Meat quality of lambs fed silk flower hay (Calotropis procera SW in the diet Qualidade de carne de cordeiros alimentados com feno de flor-de-seda (Calotropis procera SW na dieta

    Directory of Open Access Journals (Sweden)

    Roberto Germano Costa

    2011-06-01

    Full Text Available The objective of this work was to evaluate the influence of using silk flower hay replacing corn and soybean meal on physical-chemical and sensorial traits of lamb meat. It was used 32 intact Morada Nova male lambs (12.7 ± 2 kg initial body weigth on feedlot system, distributed in a completely randomized design with four levels (0, 15, 30 and 45% on dry matter basis. The use of silk flower hay in the diet influenced quality of meat and carcass, leg weight, tissue composition, moisture, juiciness and flavor. Replacing corn (26.67% and soybean (3.33% with silk flower hay does not affect the tissue composition, ratios and muscularity index of leg and physical-chemical parameters of semimembranosus muscle of Morada Nova lambs.Objetivou-se avaliar a influência do uso de feno de flor-de-seda em substituição ao milho e ao farelo de soja nas características físico-químicas e sensoriais da carne de cordeiros. Utilizaram-se 32 cordeiros Morada Nova, machos não-castrados (12,7 ± 2 kg de peso vivo inicial, em confinamento, distribuídos em delineamento inteiramente ao acaso com quatro níveis (0, 15, 30 e 45% com base na MS. A utilização de feno de flor-de-seda na dieta influenciou a qualidade da carcaça e da carne, o peso da perna, a composição tecidual, a umidade, a suculência e o sabor. A substituição do milho (26,67% e da soja (3,33% pelo feno de flor-de-seda não altera composição tecidual, relação e índice de muscularidade da perna e os parâmetros físico-químicos do músculo semimembranosus de cordeiros Morada Nova.

  15. Interação de fatores biofísicos e antrópicos com a diversidade florística na indicação de áreas para conservação do Bioma Caatinga

    OpenAIRE

    Costa, Thomaz Correa e Castro; Accioly, Luciano José de Oliveira; Oliveira, Luciana Mara Temponi; Oliveira, Maria Aparecida José de; Guimarães, Daniel Pereira

    2009-01-01

    p.19-37 A diversidade florística da caatinga foi relacionada com fatores biofísicos e antrópicos para indicação de áreas para conservação. Utilizou-se a análise multicritério para indicar regiões favoráveis à maior diversidade, por meio de fatores biofísicos, e regiões com menor pressão antrópica, a partir de variáveis sócio-econômicas extraídas do censo agropecuário. Os resultados foram comparados com inventários florísticos, fitossociológicos e de biomassa, no qual alguns fatores apresen...

  16. Causality and headache triggers

    Science.gov (United States)

    Turner, Dana P.; Smitherman, Todd A.; Martin, Vincent T.; Penzien, Donald B.; Houle, Timothy T.

    2013-01-01

    Objective The objective of this study was to explore the conditions necessary to assign causal status to headache triggers. Background The term “headache trigger” is commonly used to label any stimulus that is assumed to cause headaches. However, the assumptions required for determining if a given stimulus in fact has a causal-type relationship in eliciting headaches have not been explicated. Methods A synthesis and application of Rubin’s Causal Model is applied to the context of headache causes. From this application the conditions necessary to infer that one event (trigger) causes another (headache) are outlined using basic assumptions and examples from relevant literature. Results Although many conditions must be satisfied for a causal attribution, three basic assumptions are identified for determining causality in headache triggers: 1) constancy of the sufferer; 2) constancy of the trigger effect; and 3) constancy of the trigger presentation. A valid evaluation of a potential trigger’s effect can only be undertaken once these three basic assumptions are satisfied during formal or informal studies of headache triggers. Conclusions Evaluating these assumptions is extremely difficult or infeasible in clinical practice, and satisfying them during natural experimentation is unlikely. Researchers, practitioners, and headache sufferers are encouraged to avoid natural experimentation to determine the causal effects of headache triggers. Instead, formal experimental designs or retrospective diary studies using advanced statistical modeling techniques provide the best approaches to satisfy the required assumptions and inform causal statements about headache triggers. PMID:23534872

  17. Causality re-established.

    Science.gov (United States)

    D'Ariano, Giacomo Mauro

    2018-07-13

    Causality has never gained the status of a 'law' or 'principle' in physics. Some recent literature has even popularized the false idea that causality is a notion that should be banned from theory. Such misconception relies on an alleged universality of the reversibility of the laws of physics, based either on the determinism of classical theory, or on the multiverse interpretation of quantum theory, in both cases motivated by mere interpretational requirements for realism of the theory. Here, I will show that a properly defined unambiguous notion of causality is a theorem of quantum theory, which is also a falsifiable proposition of the theory. Such a notion of causality appeared in the literature within the framework of operational probabilistic theories. It is a genuinely theoretical notion, corresponding to establishing a definite partial order among events, in the same way as we do by using the future causal cone on Minkowski space. The notion of causality is logically completely independent of the misidentified concept of 'determinism', and, being a consequence of quantum theory, is ubiquitous in physics. In addition, as classical theory can be regarded as a restriction of quantum theory, causality holds also in the classical case, although the determinism of the theory trivializes it. I then conclude by arguing that causality naturally establishes an arrow of time. This implies that the scenario of the 'block Universe' and the connected 'past hypothesis' are incompatible with causality, and thus with quantum theory: they are both doomed to remain mere interpretations and, as such, are not falsifiable, similar to the hypothesis of 'super-determinism'.This article is part of a discussion meeting issue 'Foundations of quantum mechanics and their impact on contemporary society'. © 2018 The Author(s).

  18. Tachyons and causal paradoxes

    International Nuclear Information System (INIS)

    Maund, J.B.

    1979-01-01

    Although the existence of tachyons is not ruled out by special relativity, it appears that causal paradoxes will arise if there are tachyons. The usual solutions to these paradoxes employ some form of the reinterpretation principle. In this paper it is argued first that, the principle is incoherent, second, that even if it is not, some causal paradoxes remain, and third, the most plausible ''solution,'' which appeals to boundary conditions of the universe, will conflict with special relativity

  19. Dynamics and causality constraints

    International Nuclear Information System (INIS)

    Sousa, Manoelito M. de

    2001-04-01

    The physical meaning and the geometrical interpretation of causality implementation in classical field theories are discussed. Causality in field theory are kinematical constraints dynamically implemented via solutions of the field equation, but in a limit of zero-distance from the field sources part of these constraints carries a dynamical content that explains old problems of classical electrodynamics away with deep implications to the nature of physicals interactions. (author)

  20. Crescimento de girassol como flor em vaso em função de doses de paclobutrazol

    Directory of Open Access Journals (Sweden)

    Christina da Silva Wanderley

    2014-02-01

    Full Text Available O girassol (Helianthus annuus L., que é comumente cultivado para produção de sementes e óleo, também apresenta potencial de uso como planta ornamental. Entretanto, seu porte elevado dificulta essa utilização, principalmente como flor em vaso. Objetivou-se neste experimento avaliar os efeitos do regulador de crescimento paclobutrazol sobre o crescimento de plantas de girassol em vaso, cultivadas em sistema hidropônico, dentro de estufa, em vasos preenchidos com sílica moída. Os dois genótipos de girassol utilizados foram BRS Oásis, com capítulo marrom e altura média de 1,85 m, e Helio 358, com capítulo amarelo e altura média de 1,45 m. As doses de paclobutrazol avaliadas foram 0; 0,5; 1; 2; 4; e 6 mg L-1 , aplicadas diretamente no substrato de sílica moída. A solução nutritiva utilizada foi a de Hoagland, e as plantas foram mantidas sob aeração constante. O delineamento experimental foi o de blocos casualizados, em esquema fatorial com cinco repetições, totalizando 60 parcelas. Avaliaram-se a altura das plantas e a massa de matéria seca de raiz, caule, folhas e de capítulos. Houve efeito do paclobutrazol sobre o crescimento das plantas. O uso do paclobutrazol na dose de 2mgL-1 reduz a altura do girassol, porém não afeta a qualidade da inflorescência, o que pode viabilizar o seu uso na produção de flores de girassol como ornamentais. A sensibilidade ao paclobutrazol é maior para o genótipo Helio 358 em relação ao genótipo BRS Oásis.

  1. Alienígenas na sala: o que fazer com espécies exóticas em trabalhos de taxonomia, florística e fitossociologia?

    Directory of Open Access Journals (Sweden)

    Marcelo Freire Moro

    2012-12-01

    Full Text Available A presença cada vez mais disseminada de organismos exóticos (muitos dos quais se tornam invasores nas diferentes regiões do planeta levou ao surgimento de uma linha de pesquisa na ecologia voltada às invasões biológicas. E para permitir a comunicação entre autores também foi desenvolvido um arcabouço terminológico. Mas, apesar disso, a terminologia relativa às bioinvasões tem sido ignorada por boa parte dos botânicos no Brasil. Há uma boa dose de confusão entre botânicos sobre o que seja uma espécie exótica, naturalizada, invasora, daninha e ruderal, levando ao uso inconsistente da terminologia. Além disso, diferentes autores têm adotado posturas praticamente opostas ao lidar com espécies exóticas em suas áreas de estudo, seja na preparação de tratamentos taxonômicos, seja na publicação de levantamentos florísticos e fitossociológicos. Enquanto alguns pesquisadores incluem em floras mesmo espécies cultivadas que não se reproduzem, outros excluem plantas invasoras comuns e conspícuas. Nós apresentamos aqui, em português, os principais conceitos relativos ao tema da bioinvasão e chamamos a atenção dos autores brasileiros para a necessidade de utilizar de modo consistente o arcabouço terminológico já existente na literatura. Também propomos a adoção de rótulos claros para informar quais espécies são exóticas na área estudada, diferenciando-as das nativas, e sugerimos critérios para ajudar botânicos a decidirem quando uma planta exótica deve ou não ser incluída em tratamentos taxonômicos ou levantamentos de florística.

  2. Whole-Genome Analysis of Three Yeast Strains Used for Production of Sherry-Like Wines Revealed Genetic Traits Specific to Flor Yeasts

    Science.gov (United States)

    Eldarov, Mikhail A.; Beletsky, Alexey V.; Tanashchuk, Tatiana N.; Kishkovskaya, Svetlana A.; Ravin, Nikolai V.; Mardanov, Andrey V.

    2018-01-01

    Flor yeast strains represent a specialized group of Saccharomyces cerevisiae yeasts used for biological wine aging. We have sequenced the genomes of three flor strains originated from different geographic regions and used for production of sherry-like wines in Russia. According to the obtained phylogeny of 118 yeast strains, flor strains form very tight cluster adjacent to the main wine clade. SNP analysis versus available genomes of wine and flor strains revealed 2,270 genetic variants in 1,337 loci specific to flor strains. Gene ontology analysis in combination with gene content evaluation revealed a complex landscape of possibly adaptive genetic changes in flor yeast, related to genes associated with cell morphology, mitotic cell cycle, ion homeostasis, DNA repair, carbohydrate metabolism, lipid metabolism, and cell wall biogenesis. Pangenomic analysis discovered the presence of several well-known “non-reference” loci of potential industrial importance. Events of gene loss included deletions of asparaginase genes, maltose utilization locus, and FRE-FIT locus involved in iron transport. The latter in combination with a flor-yeast-specific mutation in the Aft1 transcription factor gene is likely to be responsible for the discovered phenotype of increased iron sensitivity and improved iron uptake of analyzed strains. Expansion of the coding region of the FLO11 flocullin gene and alteration of the balance between members of the FLO gene family are likely to positively affect the well-known propensity of flor strains for velum formation. Our study provides new insights in the nature of genetic variation in flor yeast strains and demonstrates that different adaptive properties of flor yeast strains could have evolved through different mechanisms of genetic variation. PMID:29867869

  3. Causality discovery technology

    Science.gov (United States)

    Chen, M.; Ertl, T.; Jirotka, M.; Trefethen, A.; Schmidt, A.; Coecke, B.; Bañares-Alcántara, R.

    2012-11-01

    Causality is the fabric of our dynamic world. We all make frequent attempts to reason causation relationships of everyday events (e.g., what was the cause of my headache, or what has upset Alice?). We attempt to manage causality all the time through planning and scheduling. The greatest scientific discoveries are usually about causality (e.g., Newton found the cause for an apple to fall, and Darwin discovered natural selection). Meanwhile, we continue to seek a comprehensive understanding about the causes of numerous complex phenomena, such as social divisions, economic crisis, global warming, home-grown terrorism, etc. Humans analyse and reason causality based on observation, experimentation and acquired a priori knowledge. Today's technologies enable us to make observations and carry out experiments in an unprecedented scale that has created data mountains everywhere. Whereas there are exciting opportunities to discover new causation relationships, there are also unparalleled challenges to benefit from such data mountains. In this article, we present a case for developing a new piece of ICT, called Causality Discovery Technology. We reason about the necessity, feasibility and potential impact of such a technology.

  4. Los sueños del poder : novela por Flor Romero de Nohra

    Directory of Open Access Journals (Sweden)

    Julian Garavito

    1979-04-01

    Full Text Available La novelista colombiana, oriunda de Cundinamarca, Flor Romero de Nohra ya tiene una interesante trayectoria como periodista (fundadora y directora de la revista mujer de América, como cuentista (La Ruta de El Dorado, y como novelista. Su primera obra en este genero, Tres Kilates ocho puntos obtuvo el premio Esso en 1964, Mi Capitán Fabián Sicachá fue finalista del Premio Planeta 1967 y Triquitraques del Trópico (1972 acaba de ser traducida al francés por Antoine Berman con el título Crépitant Tropique.

  5. Composición florística de pastizales en Muy Muy y Rivas, Nicaragua

    OpenAIRE

    Morales, Julio; Rusch, Graciela; Casanoves, Fernando; Söderström, Lars; Rocha, Lester

    2013-01-01

    A pesar de ser ecosistemas manejados, surgidos de la transformación de ambientes naturales, los pastizales compuestos por especies nativas y exóticas pueden tener un papel importante en la conservación de la biodiversidad y en la prestación de servicios ecosistémicos; entre ellos, la producción de forraje, la polinización y el control biológico. El presente estudio evalúa y compara la riqueza, similitud florística y distribución de plantas en pastizales seminaturales de dos zonas ganaderas: C...

  6. A quantum causal discovery algorithm

    Science.gov (United States)

    Giarmatzi, Christina; Costa, Fabio

    2018-03-01

    Finding a causal model for a set of classical variables is now a well-established task—but what about the quantum equivalent? Even the notion of a quantum causal model is controversial. Here, we present a causal discovery algorithm for quantum systems. The input to the algorithm is a process matrix describing correlations between quantum events. Its output consists of different levels of information about the underlying causal model. Our algorithm determines whether the process is causally ordered by grouping the events into causally ordered non-signaling sets. It detects if all relevant common causes are included in the process, which we label Markovian, or alternatively if some causal relations are mediated through some external memory. For a Markovian process, it outputs a causal model, namely the causal relations and the corresponding mechanisms, represented as quantum states and channels. Our algorithm opens the route to more general quantum causal discovery methods.

  7. Causal symmetric spaces

    CERN Document Server

    Olafsson, Gestur; Helgason, Sigurdur

    1996-01-01

    This book is intended to introduce researchers and graduate students to the concepts of causal symmetric spaces. To date, results of recent studies considered standard by specialists have not been widely published. This book seeks to bring this information to students and researchers in geometry and analysis on causal symmetric spaces.Includes the newest results in harmonic analysis including Spherical functions on ordered symmetric space and the holmorphic discrete series and Hardy spaces on compactly casual symmetric spacesDeals with the infinitesimal situation, coverings of symmetric spaces, classification of causal symmetric pairs and invariant cone fieldsPresents basic geometric properties of semi-simple symmetric spacesIncludes appendices on Lie algebras and Lie groups, Bounded symmetric domains (Cayley transforms), Antiholomorphic Involutions on Bounded Domains and Para-Hermitian Symmetric Spaces

  8. Causal inference in econometrics

    CERN Document Server

    Kreinovich, Vladik; Sriboonchitta, Songsak

    2016-01-01

    This book is devoted to the analysis of causal inference which is one of the most difficult tasks in data analysis: when two phenomena are observed to be related, it is often difficult to decide whether one of them causally influences the other one, or whether these two phenomena have a common cause. This analysis is the main focus of this volume. To get a good understanding of the causal inference, it is important to have models of economic phenomena which are as accurate as possible. Because of this need, this volume also contains papers that use non-traditional economic models, such as fuzzy models and models obtained by using neural networks and data mining techniques. It also contains papers that apply different econometric models to analyze real-life economic dependencies.

  9. Número de anteras por flor, grãos de pólen por antera e capacidade germinativa do pólen de diferentes cultivares de macieiras

    Directory of Open Access Journals (Sweden)

    Celso Lopes de Albuquerque Junior

    2010-12-01

    Full Text Available O objetivo deste trabalho foi avaliar o número de anteras por flor, grãos de pólen por antera e capacidade germinativa do pólen de diferentes cultivares de macieiras. O trabalho foi executado no Laboratório de Fisiologia do Desenvolvimento e Genética Vegetal da Universidade Federal de Santa Catarina, e as coletas a campo foram realizadas na Epagri/Estação Experimental de Caçador-SC, em outubro de 2005. Foram utilizadas as seguintes cultivares comerciais de macieira desenvolvidas no Brasil: Primícia, Princesa, Fred Hough, Catarina, Baronesa, Lisgala, Suprema, Condessa, Daiane, Duquesa, Imperatriz e Joaquina. As cultivares de macieira Condessa, Princesa, Eva, Duquesa, Imperatriz, Gala, Fred Hough, Daiane, Baronesa e Suprema produzem pólen em quantidade suficiente e com boa capacidade germinativa. A cv. Condessa, embora apresente alta capacidade germinativa de pólen, produz menos anteras e grãos de pólen por antera que as demais. A cv. Princesa é a que apresenta o melhor perfil como polinizadora, por conjugar número de anteras/flor, número de grãos de pólen/antera e capacidade germinativa do pólen mais satisfatórios.

  10. Composição florística de uma floresta estacional semidecidual montana no município de Viçosa-MG Floristic composition of a montane seasonal semideciduous tropical forest in Viçosa, MG, Brasil

    Directory of Open Access Journals (Sweden)

    João Augusto Alves Meira-Neto

    2002-08-01

    Full Text Available O objetivo do presente estudo foi investigar a composição florística arbórea da Mata da Silvicultura (20º45'S e 42º55'W, município de Viçosa, Zona da Mata de Minas Gerais, com o intuito de avaliar sua similaridade com outras florestas. Para comparação florística foi utilizada a análise de agrupamentos pelo método de médias aritméticas não-ponderadas (UPGMA, a partir dos índices binários de similaridade de Sørensen entre as florestas comparadas. Foram relacionadas 154 espécies de 47 famílias botânicas para a Mata da Silvicultura. Esta mata mostrou-se mais similar às florestas semideciduais de altitude de Lavras (MG e de Atibaia (SP e menos similar às florestas submontanas e litorâneas. Estes resultados evidenciam uma importante influência das temperaturas na determinação do tipo florístico das florestas do Sudeste e Sul brasileiros.This study aims to investigate the floristic composition of the Silvicultura forest (20º45`S and 42º55´W by comparing it to other forest compositions. Thus, the cluster analysis method of unweighted pair-group using arithmetic averages (UPGMA was used, applying the Sørensen binary similarity index found among compared forests. A list of 154 species of 47 families was recorded. The Silvicultura forest is more similar to the montane semideciduous forests of Lavras and Atibaia, but less similar to submontane and coastal forests. These results show that temperature plays an important role in the floristic differentiation of the southern and southeastern Brazilian forest types.

  11. Condicionamento fisiológico de sementes de couve-flor Priming seed treatment of cauliflower seeds

    Directory of Open Access Journals (Sweden)

    Ana Lúcia P Kikuti

    2009-06-01

    Full Text Available Esta pesquisa teve como objetivos definir o procedimento para o condicionamento fisiológico de sementes de couve-flor e verificar a influência do potencial fisiológico das sementes sobre os resultados desse tratamento. Seis lotes de sementes, três da cultivar Sharon e três da cultivar Teresópolis Gigante, foram submetidos ao hidrocondicionamento entre camadas de duas, quatro e seis folhas de papel toalha e ao osmocondicionamento entre camadas de quatro folhas de papel toalha umedecidas com solução de polietilenoglicol 6000 (potenciais de -0,1 e -0,2 MPa. Em todos os procedimentos os teores de água foram ajustados para 32 e 38%, para a cultivar Sharon, e 34 e 41% para a cultivar Teresópolis Gigante. Os efeitos dos tratamentos sobre a germinação e emergência das plântulas foram comparados à testemunha (sem condicionamento. O hidrocondicionamento entre quatro e seis folhas, até a obtenção dos teores de água mais elevados, beneficiou a velocidade de germinação (VG e a de emergência de plântulas (VE, nas duas cultivares. Na cultivar Sharon a VG foi de 14,6 (testemunha em comparação a 16,4 nas sementes hidrocondicionadas, para os lotes de maior e menor potencial fisiológico; paralelamente, os valores da VE aumentaram de 8,9 para 11,2 e de 7,8 para 11,6, nos lotes de menor potencial fisiológico. Para a cultivar Teresópolis Gigante, a VG e a VE foram favorecidas pelo hidrocondicionamento, independentemente do potencial fisiológico dos lotes (a VG aumentou de 16,4 para 21,4 e, a VE, de 9,5 para 13,5. Conclui-se que o hidrocondicionamento entre quatro e seis folhas de papel toalha, até a obtenção de teores de água próximos aos da emissão da raiz primária é favorável à velocidade de germinação e de emergência de plântulas em couve-flor e que o potencial fisológico inicial dos lotes pode influenciar a resposta ao condicionamento fisiológico, dependendo da cultivar ou histórico dos lotes.This research was

  12. Florística e estrutura de um fragmento de Floresta Ombrófila Mista no Planalto Catarinense

    Directory of Open Access Journals (Sweden)

    Carine Klauberg

    2010-04-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2010v23n1p35 O Planalto Catarinense constitui-se em uma importante região estratégica para estudos referentes à conservação, em função da ocorrência de remanescentes de Floresta Ombrófila Mista e por ser uma área de recarga e afloramento do aquífero Guarani. Com o objetivo de avaliar a similaridade florística entre diferentes áreas amostrais e descrever a estrutura do componente arbóreo, foram alocadas, no Parque Natural Municipal de Lages, SC, quatro parcelas permanentes (40 x 40m e cada uma foi dividida em 16 unidades amostrais de 10 x 10m. Árvores com DAP ≥ 5cm foram mapeadas, marcadas e mensuradas. Os espécimes foram coletados, identificados e depositados em herbário. Foram amostradas 46 espécies distribuídas em 39 gêneros e 27 famílias. As famílias mais ricas em espécies foram Myrtaceae, Lauraceae, Salicaceae e Sapindaceae as quais apresentaram alta densidade, assim como Dicksoniaceae e Clethraceae. Sete espécies somaram mais de 60% do total de indivíduos amostrados. A diversidade específica (H’ foi de 3,05 nats.ind-1 (J’= 0,81. A similaridade entre as parcelas foi de 32 a 44%, indicando baixa semelhança entre as parcelas estudadas. A distribuição espacial da maioria das espécies é classificada como agregada, conforme o índice de Morisita. Esta floresta é considerada rica e diversa, com espécies arbóreas ameaçadas de extinção tais como Araucaria angustifolia e Dicksonia sellowiana. Devido à grande importância ecológica para a flora e fauna local e o processo de fragmentação na região, este remanescente florestal deve ser protegido e conservado, visto que ainda ocorrem interferências antrópicas negativas.

  13. Monitoreo de tortugas marinas Lepidochelis olivaceae (paslama en playa La Flor - Rivas

    Directory of Open Access Journals (Sweden)

    Celia María Gutiérrez

    1999-12-01

    Full Text Available La tortuga marina Lepidochelis olivaceae desova en forma masiva, solamente en seis playas del mundo. Nicaragua cuenta con dos de estas playas en los sitios geográficos llamados ' “Chacocente", en el Departamento de Carazo y "La Flor", en San Juan del Sur. Esta especie de tortuga se caracteriza por presentar un movimiento sincronizado para su anidación en la playa, el cual se ha denominado arribadas. Durante 5 años consecutivos se realizó en el refugio de vida silvestre "La Flor", un monitoreo de la población anidante y se encontró que cada año durante el período de julio a enero, visitan esta playa aproximadamente, 3,000 a 12,000 tortugas, reportándose entre septiembre y octubre el pico más alto de la población anidante. Paralelo a este estudio, se realizó un diagnóstico rápido en las comunidades aledañas al refugio, el cual refleja que es una práctica tradicional de los pobladores, la extracción de huevos de tortuga para el consumo de la familia y para el comercio. Se considera, sin embargo, que esta práctica no representa económicamente una dependencia absoluta, ya que la población tiene otros tipos de actividades agropecuarias que contribuyen a su subsistencia.

  14. Maximally causal quantum mechanics

    International Nuclear Information System (INIS)

    Roy, S.M.

    1998-01-01

    We present a new causal quantum mechanics in one and two dimensions developed recently at TIFR by this author and V. Singh. In this theory both position and momentum for a system point have Hamiltonian evolution in such a way that the ensemble of system points leads to position and momentum probability densities agreeing exactly with ordinary quantum mechanics. (author)

  15. Causality in demand

    DEFF Research Database (Denmark)

    Nielsen, Max; Jensen, Frank; Setälä, Jari

    2011-01-01

    to fish demand. On the German market for farmed trout and substitutes, it is found that supply sources, i.e. aquaculture and fishery, are not the only determinant of causality. Storing, tightness of management and aggregation level of integrated markets might also be important. The methodological...

  16. Causality and Free Will

    Czech Academy of Sciences Publication Activity Database

    Hvorecký, Juraj

    2012-01-01

    Roč. 19, Supp.2 (2012), s. 64-69 ISSN 1335-0668 R&D Projects: GA ČR(CZ) GAP401/12/0833 Institutional support: RVO:67985955 Keywords : conciousness * free will * determinism * causality Subject RIV: AA - Philosophy ; Religion

  17. Explaining through causal mechanisms

    NARCIS (Netherlands)

    Biesbroek, Robbert; Dupuis, Johann; Wellstead, Adam

    2017-01-01

    This paper synthesizes and builds on recent critiques of the resilience literature; namely that the field has largely been unsuccessful in capturing the complexity of governance processes, in particular cause–effects relationships. We demonstrate that absence of a causal model is reflected in the

  18. Composição florística de trechos florestais na borda sul-amazônica Floristic composition of forest patches in Southern Amazonia

    Directory of Open Access Journals (Sweden)

    Natália Macedo Ivanauskas

    2004-09-01

    Full Text Available Este estudo apresenta a composição florística de trechos de uma faixa de vegetação de transição existente na região centro-leste do Estado de Mato Grosso, mais precisamente no município de Gaúcha do Norte (13° 10'S e 53° 15' O, onde dá-se o contato entre a Floresta Ombrófila e a Floresta Estacional. O levantamento florístico foi realizado em março de 1999 e bimestralmente a partir de agosto de 1999 até março de 2001, em excursões com duração média de 5 dias, por meio de caminhadas na borda e no interior de florestas, sendo coletadas fanerógamas em fase reprodutiva. Também foram incluídas amostras vegetativas de espécies arbustivo-arbóreas, que não floresceram ou frutificaram durante o período de amostragem, amostradas em 3ha destinados ao levantamento fitossociológico. O levantamento florístico resultou em 72 famílias, 168 gêneros e 268 espécies. Do total de espécies, 66% apresentaram hábito arbóreo e 18% foram lianas. As ervas e arbustos praticamente restringiram-se às áreas de borda ou clareiras, somando 13%. Já a flora epifítica mostrou-se pouco expressiva (1%, quando comparada ao restante da Amazônia, em conseqüência do clima regional mais seco. Hemiepífitas, parasitas e palmeiras constituíram o percentual restante. Constatou-se que 39 espécies amostradas em Gaúcha do Norte ainda não haviam sido depositadas em herbários que mantém coleções representativas da flora matogrossense, enfatizando a carência de coletas nas áreas florestais do Estado.This paper shows the floristic composition of forest patches in a zone of transition vegetation which exists in the central-east region of Mato Grosso state, more specifically in the municipality of Gaúcha do Norte (13° 10'S and 53° 15' W where it connects the tropical rain-forest and the seasonal forest. The floristic survey was performed in March 1999 and bisemesterly from August 1999 to March 2001 (during excursions of an average of five days

  19. Resposta de brócolis, couve-flor e repolho à adubação com boro em solo arenoso Response of boron fertilization on broccoli, cauliflower and cabbage planted in sandy soil

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Pizetta

    2005-03-01

    Full Text Available Foram avaliados em condições de campo, em solo arenoso, com baixo teor de boro, os efeitos da adubação com cinco doses de boro (0; 2; 4; 6 e 8 kg ha-1 de B na forma de bórax na produção de brócolis, couve-flor e repolho. O experimento obedeceu a um esquema fatorial com delineamento experimental de blocos ao acaso com três repetições. As adubações orgânica e química, inclusive o bórax, foram feitas no sulco antes do transplantio das mudas e a colheita foi feita entre 63 e 93 dias após o transplantio. A produtividade de brócolis variou de 16,9 a 20,5 t ha-1; a de couve-flor de 21,6 a 29,6 t ha-1 e a de repolho de 40,5 a 46,4 t ha-1. O aumento observado na produtividade de brócolis e de repolho foi linear e o efeito das doses de boro na produtividade de couve-flor foi quadrático, sendo necessários 5,1 kg ha-1 de B para atingir a produtividade máxima de 30 t ha-1. Brócolis e repolho mostraram-se menos sensíveis do que a couve-flor tanto à deficiência quanto ao excesso de boro. No caso da couve-flor, com a aplicação de 2 kg ha-1 ou de 6 kg ha-1 de B houve significativa perda de qualidade do produto.The effects of boron fertilization on yield of broccoli, cauliflower and cabbage were evaluated through a field experiment carried out on a sandy soil low in available boron. Five boron levels (0; 2; 4; 6; and 8 kg ha-1 B as borax were applied in broccoli, cauliflower and cabbage using a factorial scheme and a randomized block design with three replicates. Organic manure and chemical fertilizers, including borax, were applied in the planting furrow before seedlings transplant and plants were harvested 63 to 93 days after planting date. The yield intervals obtained with broccoli, cauliflower and cabbage varied according to the following intervals: 16.9 to 20.5 t ha-1, 21.6 to 29.6 t ha-1 and 40.5 to 46.3 t ha-1, respectively. The increase in production observed in broccoli and cabbage yield was linear with boron levels and the

  20. A Collaboration in Support of LBA Science and Data Exchange: Beija-flor and EOS-WEBSTER

    Science.gov (United States)

    Schloss, A. L.; Gentry, M. J.; Keller, M.; Rhyne, T.; Moore, B.

    2001-12-01

    The University of New Hampshire (UNH) has developed a Web-based tool that makes data, information, products, and services concerning terrestrial ecological and hydrological processes available to the Earth Science community. Our WEB-based System for Terrestrial Ecosystem Research (EOS-WEBSTER) provides a GIS-oriented interface to select, subset, reformat and download three main types of data: selected NASA Earth Observing System (EOS) remotely sensed data products, results from a suite of ecosystem and hydrological models, and geographic reference data. The Large Scale Biosphere-Atmosphere Experiment in Amazonia Project (LBA) has implemented a search engine, Beija-flor, that provides a centralized access point to data sets acquired for and produced by LBA researchers. The metadata in the Beija-flor index describe the content of the data sets and contain links to data distributed around the world. The query system returns a list of data sets that meet the search criteria of the user. A common problem when a user of a system like Beija-flor wants data products located within another system is that users are required to re-specify information, such as spatial coordinates, in the other system. This poster describes methodology by which Beija-flor generates a unique URL containing the requested search parameters and passes the information to EOS-WEBSTER, thus making the interactive services and large diverse data holdings in EOS-WEBSTER directly available to Beija-flor users. This "Calling Card" is used by EOS-WEBSTER to generate on-demand custom products tailored to each Beija-flor request. Through a collaborative effort, we have demonstrated the ability to integrate project-specific search engines such as Beija-flor with the products and services of large data systems such as EOS-WEBSTER, to provide very specific information products with a minimal amount of additional programming. This methodology has the potential to greatly facilitate research data exchange by

  1. Optimal causal inference: estimating stored information and approximating causal architecture.

    Science.gov (United States)

    Still, Susanne; Crutchfield, James P; Ellison, Christopher J

    2010-09-01

    We introduce an approach to inferring the causal architecture of stochastic dynamical systems that extends rate-distortion theory to use causal shielding--a natural principle of learning. We study two distinct cases of causal inference: optimal causal filtering and optimal causal estimation. Filtering corresponds to the ideal case in which the probability distribution of measurement sequences is known, giving a principled method to approximate a system's causal structure at a desired level of representation. We show that in the limit in which a model-complexity constraint is relaxed, filtering finds the exact causal architecture of a stochastic dynamical system, known as the causal-state partition. From this, one can estimate the amount of historical information the process stores. More generally, causal filtering finds a graded model-complexity hierarchy of approximations to the causal architecture. Abrupt changes in the hierarchy, as a function of approximation, capture distinct scales of structural organization. For nonideal cases with finite data, we show how the correct number of the underlying causal states can be found by optimal causal estimation. A previously derived model-complexity control term allows us to correct for the effect of statistical fluctuations in probability estimates and thereby avoid overfitting.

  2. Estudo do sistema de reprodução da fava-d'anta (Dimorphandra mollis Benth.

    Directory of Open Access Journals (Sweden)

    A.D.R. Mendes

    2013-01-01

    Full Text Available Entre as plantas nativas de uso medicinal do Cerrado brasileiro encontra-se a fava-d'anta (Dimorphandra mollis Benth com alto potencial econômico por possuir inúmeras potencialidades medicinais e fitoquímicas. A indústria extrai dos frutos os princípios ativos rutina, quercetina, e ramnose, dentre outros, usados na fabricação de medicamentos e cosméticos, principalmente no exterior. O conhecimento do sistema reprodutivo da espécie é fundamental para sua conservação e manejo. O presente trabalho objetivou determinar as características morfométricas das flores e caracterizar o sistema reprodutivo da D. mollis em área de Cerrado inalterada antropomorficamente, no município de Olhos D'água - MG. Para as características morfométricas, diâmetro da flor, comprimento da flor, do ovário, e da antera, foram utilizadas cinco flores em pré-antese. Para a determinação do sistema reprodutivo utilizou-se a razão pólen:óvulo (P:O, em 40 flores. As flores da D. mollis apresentaram comprimento da flor de 3,00 mm, diâmetro da flor de 2,00 mm, comprimento do óvulo de 2,60 mm, comprimento da antera de 1,57 mm, e o número de óvulos e de anteras foram 20 e 5,8, respectivamente. A razão P:O foi 765,030, sendo que esse índice não é afetado pelas características morfométricas. O sistema reprodutivo da D. mollis foi classificado como alógama facultativa.

  3. Operator ordering and causality

    OpenAIRE

    Plimak, L. I.; Stenholm, S. T.

    2011-01-01

    It is shown that causality violations [M. de Haan, Physica 132A, 375, 397 (1985)], emerging when the conventional definition of the time-normal operator ordering [P.L.Kelley and W.H.Kleiner, Phys.Rev. 136, A316 (1964)] is taken outside the rotating wave approximation, disappear when the amended definition [L.P. and S.S., Annals of Physics, 323, 1989 (2008)] of this ordering is used.

  4. Space, time and causality

    International Nuclear Information System (INIS)

    Lucas, J.R.

    1984-01-01

    Originating from lectures given to first year undergraduates reading physics and philosophy or mathematics and philosophy, formal logic is applied to issues and the elucidation of problems in space, time and causality. No special knowledge of relativity theory or quantum mechanics is needed. The text is interspersed with exercises and each chapter is preceded by a suggested 'preliminary reading' and followed by 'further reading' references. (U.K.)

  5. Análise florística e estrutura fitossociológica de um fragmento de Floresta Ombrófila Mista no município de Sertão - RSFloristic analysis and phytosociological structure of a Mixed Ombrophylous Forest

    OpenAIRE

    Piroli, Edson Luis; Universidade Estadual Paulista Júlio de Mesquita Filho - UNESP; Nascimento, André Rosalvo Terra; Universidade Federal de Uberlândia - UFU

    2009-01-01

    Neste trabalho foram estudadas a composição florística e estrutura fitossociológica de um fragmento de Floresta Ombrófila Mista no município de Sertão, RS, com área aproximada de 700 ha. A análise estrutural destaca Araucaria angustifolia (Bertol.) Kuntze, como espécie dominante, principalmente na periferia do fragmento apresentando um número relativamente menor de indivíduos no interior da floresta. Abstract This paper appraises the study of the floristic composition and phytosociological st...

  6. Caracterização florística de uma área de contato entre Cerrado e Mata Atlântica na região sudoeste do Estado de São Paulo.

    OpenAIRE

    Nicole da Silva PINTO; Natalia de Oliveira COSTA; Ana Carolina de Oliveira BARBOSA; Conceição Rodrigues de LIMA; Maria Teresa Zugliani TONIATO; Geraldo Antonio Daher Corrêa FRANCO; João Aurélio PASTORE; Osny Tadeu de AGUIAR; João Batista BAITELLO; Roque CIELO-FILHO; Silvana Cristina Pereira Muniz de SOUZA

    2012-01-01

    Remanescentes de vegetação nativa em áreas de contato florístico e fitogeográfico têm especial importância na conservação da biodiversidade. A EstaçãoExperimental de Itapeva – EExI apresenta os referidos atributos, pois, abriga remanescentes de Floresta Estacional Semidecidual e de Cerrado. A EExI está localizada na BaciaHidrográfica do Alto Paranapanema – BHAP, na região sudoeste do Estado de São Paulo, considerada altamente degradada e prioritária para estudos de flora e fauna. Os objetivos...

  7. Composição florística do estrato arbóreo de floresta Atlântica Interiorana em Araponga - Minas Gerais Tree strtum floristc composition of an Inland Atlantic forest in Araponga - MG

    Directory of Open Access Journals (Sweden)

    Michellia Pereira Soares

    2006-10-01

    Full Text Available Os objetivos deste trabalho foram determinar a composição florística de um fragmento de Floresta e analisar a sua similaridade com outras áreas de Floresta Estacional Semidecidual e Floresta Ombrófila Densa, com o intuito de classificar a tipologia florestal da área de estudo. O levantamento foi realizado em uma trilha interpretativa na Pousada Serra D'Água (20º41'24"S e 42º29'47"W, 1.100 m de altitude, região de entorno do Parque Estadual da Serra do Brigadeiro (PESB, Município de Araponga, MG. A listagem florística foi obtida a partir do levantamento fitossociológico, no qual foram demarcados 150 pontos quadrantes. Foram relacionadas 147 espécies, 98 gêneros e 50 famílias. As famílias com maior número de espécies foram: Melastomataceae (14, Leguminosae (11, Myrtaceae (10, Rubiaceae (8, Annonaceae (7, Flacourtiaceae (7, Lauraceae (7 e Meliaceae (6. Os resultados da análise de agrupamento revelaram que os aspectos de proximidade geográfica e altitude são os principais responsáveis pela similaridade florística de muitas áreas. A vegetação da área de estudo pode ser classificada como Floresta Estacional Semidecidual Montana, pelo fato de a sua composição florística mostrar alta similaridade com outras áreas dessa mesma tipologia.The objective of this work was to determine the floristic composition of a forest fragment and to analyze its similarity with other areas of the Semideciduous Seasonal Forest and Dense Ombrophylous Forest, in order to classify the forest typology of this area. The survey was carried out in an interpretative trail at the Pousada Serra D'Água (20º41'24"S and 42º29'47"W, 1100 m altitude, in the region around the Serra do Brigadeiro State Park (PESB, municipality of Araponga, MG. The floristic list was obtained from the phytosociological survey in which 150 quarter-centered-points were established. A total of 147 species, 98 genera and 50 families were found. The families with the greatest

  8. Florística e estrutura do componente arbóreo e análise ambiental de um fragmento de Floresta Ombrófila Mista Alto-Montana no município de Painel, SC

    Directory of Open Access Journals (Sweden)

    Pedro Higuchi

    2013-03-01

    Full Text Available http://dx.doi.org/10.5902/198050988449A Floresta Ombrófila Mista Alto-Montana é uma formação pouco estudada que ocorre em altitudes acima de 1.000 m. Os objetivos deste estudo foram conhecer os padrões florísticos e estruturais do componente arbóreo de um fragmento desta floresta na região do Planalto Sul Catarinense e determinar as variáveis ambientais que influenciam esses padrões. O levantamento da composição florística e estrutural e a coleta das variáveis ambientais foram conduzidos em 50 parcelas de 200 m2. Nelas, todos os indivíduos arbóreos com CAP (circunferência medida a altura do peito ≥ 15,7 cm foram medidos (CAP e altura e identificados. Foram coletadas, em cada parcela, variáveis ambientais relacionadas às características químicas e físicas dos solos, topográficas e de cobertura do dossel. Foram calculados os parâmetros fitossociológicos e a estrutura diamétrica da comunidade e das populações com valor de importância (VI acima de 5 %. A similaridade florístico-estrutural entre as parcelas foi analisada pela NMDS (Nonmetric Multidimensional Scaling e os vetores das variáveis ambientais significativas (p < 0,05 foram plotados a posteriori. Foram identificadas 50 espécies arbóreas distribuídas em 33 gêneros e 20 famílias botânicas. As espécies com maior VI foram: Araucaria angustifolia (Bertol. Kuntze (17,32 %, Myrceugenia euosma (O.Berg D.Legrand (15,24 % e Acca sellowiana (O.Berg Burret (7,84 %. A estrutura diamétrica de toda a comunidade e das populações estudadas (exceto Dicksonia sellowiana Hook. teve distribuição próxima ao “J invertido”. A análise NMDS demonstrou maior porcentagem de argila nas parcelas com maior densidade de Araucaria angustifolia e menor porcentagem, nas parcelas com maior densidade de Dicksonia sellowiana, Inga lentiscifolia Benth. e Ocotea pulchella Mart. As parcelas de maior declividade tiveram maior densidade de Drimys brasiliensis Miers e aquelas de

  9. Estudio florístico de los páramos de pajonal meridionales de Ecuador

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    Jesús Izco

    2013-04-01

    Full Text Available El presente trabajo es un estudio de la flora de los páramos de pajonal seriales de distintos macizos montañosos de los Andes del Sur de Ecuador (provincias de Azuay y Loja comprendidos entre los 2850 m y 3635 m. Fueron identificadas 43 familias de plantas vasculares, 120 géneros y 216 especies. La flora local es comparada con la de otros páramos de pajonal andinos; la riqueza florística (géneros y especies es analizada por tramos altitudinales y se establece la flora característica de cada tramo del territorio estudiado. De forma complementaria, discutimos las influencias biogeográficas de la flora de los páramos de pajonal.

  10. “Finance-Growth-Crisis Nexus in India: Evidence from Cointegration and Causality Assessment” - L’interazione finanza-crescita-crisi in India: evidenze da una analisi di cointegrazione e causalità

    OpenAIRE

    Fukuda, Takashi; Dahalan, Jauhari

    2011-01-01

    This paper attempts to explore a new dimension of India’s ‘financegrowth- crisis’ nexus. For this end, the summary indicators of financial development, financial crisis and financial repression are created through the principal component approach, and we perform the cointegration and Granger causality analysis employing the methods of vector error correction model (VECM) and autoregressive distributed lag (ARDL). The element of structural break is also taken into assessment while specifying t...

  11. Causal events enter awareness faster than non-causal events

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    Pieter Moors

    2017-01-01

    Full Text Available Philosophers have long argued that causality cannot be directly observed but requires a conscious inference (Hume, 1967. Albert Michotte however developed numerous visual phenomena in which people seemed to perceive causality akin to primary visual properties like colour or motion (Michotte, 1946. Michotte claimed that the perception of causality did not require a conscious, deliberate inference but, working over 70 years ago, he did not have access to the experimental methods to test this claim. Here we employ Continuous Flash Suppression (CFS—an interocular suppression technique to render stimuli invisible (Tsuchiya & Koch, 2005—to test whether causal events enter awareness faster than non-causal events. We presented observers with ‘causal’ and ‘non-causal’ events, and found consistent evidence that participants become aware of causal events more rapidly than non-causal events. Our results suggest that, whilst causality must be inferred from sensory evidence, this inference might be computed at low levels of perceptual processing, and does not depend on a deliberative conscious evaluation of the stimulus. This work therefore supports Michotte’s contention that, like colour or motion, causality is an immediate property of our perception of the world.

  12. Use of a flor velum yeast for modulating colour, ethanol and major aroma compound contents in red wine.

    Science.gov (United States)

    Moreno, Juan; Moreno-García, Jaime; López-Muñoz, Beatriz; Mauricio, Juan Carlos; García-Martínez, Teresa

    2016-12-15

    The most important and negative effect of the global warming for winemakers in warm and sunny regions is the observed lag between industrial and phenolic grape ripeness, so only it is possible to obtain an acceptable colour when the ethanol content of wine is high. By contrast, the actual market trends are to low ethanol content wines. Flor yeast growing a short time under velum conditions, decreases the ethanol and volatile acidity contents, has a favorable effect on the colour and astringency and significantly changes the wine content in 1-propanol, isobutanol, acetaldehyde, 1,1-diethoxiethane and ethyl lactate. The Principal Component Analysis of six enological parameters or five aroma compounds allows to classify the wines subjected to different velum formation conditions. The obtained results in two tasting sessions suggest that the flor yeast helps to modulate the ethanol, astringency and colour and supports a new biotechnological perspective for red winemakers. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. FLO11 expression and lipid biosynthesis are required for air-liquid biofilm formation in a Saccharomyces cerevisiae flor strain.

    Science.gov (United States)

    Zara, Giacomo; Goffrini, Paola; Lodi, Tiziana; Zara, Severino; Mannazzu, Ilaria; Budroni, Marilena

    2012-11-01

    Air-liquid biofilm formation is largely dependent on Flo11p and seems related to cell lipid content and composition. Here, it is shown that in the presence of cerulenin, a known inhibitor of the fatty acid synthase complex, biofilm formation is inhibited together with FLO11 transcription in a flor strain of Saccharomyces cerevisiae, while the administration of saturated fatty acids to cerulenin-containing medium restores biofilm formation and FLO11 transcription. It is also shown that, in biofilm cells, the FLO11 transcription is accompanied by the transcription of ACC1, ACS1 and INO1 key genes in lipid biosynthesis and that biofilm formation is affected by the lack of inositol in flor medium. These results are compatible with the hypothesis that the air-liquid biofilm formation depends on FLO11 transcription levels as well as on fatty acids biosynthesis. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  14. Causal inference based on counterfactuals

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    Höfler M

    2005-09-01

    Full Text Available Abstract Background The counterfactual or potential outcome model has become increasingly standard for causal inference in epidemiological and medical studies. Discussion This paper provides an overview on the counterfactual and related approaches. A variety of conceptual as well as practical issues when estimating causal effects are reviewed. These include causal interactions, imperfect experiments, adjustment for confounding, time-varying exposures, competing risks and the probability of causation. It is argued that the counterfactual model of causal effects captures the main aspects of causality in health sciences and relates to many statistical procedures. Summary Counterfactuals are the basis of causal inference in medicine and epidemiology. Nevertheless, the estimation of counterfactual differences pose several difficulties, primarily in observational studies. These problems, however, reflect fundamental barriers only when learning from observations, and this does not invalidate the counterfactual concept.

  15. Causal inference in public health.

    Science.gov (United States)

    Glass, Thomas A; Goodman, Steven N; Hernán, Miguel A; Samet, Jonathan M

    2013-01-01

    Causal inference has a central role in public health; the determination that an association is causal indicates the possibility for intervention. We review and comment on the long-used guidelines for interpreting evidence as supporting a causal association and contrast them with the potential outcomes framework that encourages thinking in terms of causes that are interventions. We argue that in public health this framework is more suitable, providing an estimate of an action's consequences rather than the less precise notion of a risk factor's causal effect. A variety of modern statistical methods adopt this approach. When an intervention cannot be specified, causal relations can still exist, but how to intervene to change the outcome will be unclear. In application, the often-complex structure of causal processes needs to be acknowledged and appropriate data collected to study them. These newer approaches need to be brought to bear on the increasingly complex public health challenges of our globalized world.

  16. Causal Diagrams for Empirical Research

    OpenAIRE

    Pearl, Judea

    1994-01-01

    The primary aim of this paper is to show how graphical models can be used as a mathematical language for integrating statistical and subject-matter information. In particular, the paper develops a principled, nonparametric framework for causal inference, in which diagrams are queried to determine if the assumptions available are sufficient for identifiying causal effects from non-experimental data. If so the diagrams can be queried to produce mathematical expressions for causal effects in ter...

  17. Diversidad Florística de la cuenca alta del rio Tambo-Ichuña, Moquegua, Perú

    NARCIS (Netherlands)

    Montesinos, D.B.

    2011-01-01

    La diversidad florística de plantas vasculares es estudiada en la cuenca del río Tambo-Ichuña, la puna y bofedales altoandinos en los distritos de Ichuña, Ubinas y Yunga (3400 – 4700 m de altitud), provincia General Sánchez Cerro, departamento de Moquegua, Perú. La flora vascular de esta región está

  18. Causality Statistical Perspectives and Applications

    CERN Document Server

    Berzuini, Carlo; Bernardinell, Luisa

    2012-01-01

    A state of the art volume on statistical causality Causality: Statistical Perspectives and Applications presents a wide-ranging collection of seminal contributions by renowned experts in the field, providing a thorough treatment of all aspects of statistical causality. It covers the various formalisms in current use, methods for applying them to specific problems, and the special requirements of a range of examples from medicine, biology and economics to political science. This book:Provides a clear account and comparison of formal languages, concepts and models for statistical causality. Addr

  19. Causal electromagnetic interaction equations

    International Nuclear Information System (INIS)

    Zinoviev, Yury M.

    2011-01-01

    For the electromagnetic interaction of two particles the relativistic causal quantum mechanics equations are proposed. These equations are solved for the case when the second particle moves freely. The initial wave functions are supposed to be smooth and rapidly decreasing at the infinity. This condition is important for the convergence of the integrals similar to the integrals of quantum electrodynamics. We also consider the singular initial wave functions in the particular case when the second particle mass is equal to zero. The discrete energy spectrum of the first particle wave function is defined by the initial wave function of the free-moving second particle. Choosing the initial wave functions of the free-moving second particle it is possible to obtain a practically arbitrary discrete energy spectrum.

  20. CACTÁCEAS NATIVAS ASSOCIADAS A FENOS DE FLOR DE SEDA E SABIÁ NA ALIMENTAÇÃO DE BORREGOS

    Directory of Open Access Journals (Sweden)

    JOSÉ GERALDO MEDEIROS DA SILVA

    2010-01-01

    Full Text Available The objective of this study was to evaluate the utilization effects of two native cacti named mandacaru (Cereus jamacaru DC. and xiquexique [Pilosocereus gounellei (A. Weber ex K. Schum. Bly ex Rowl.] associated with sabiá (Mimosa caesalpiniifolia Benth. and flor de seda (Calotropis procera (Ait. R.Br. about the nutrient intake, daily weight gain, and feed conversion in sheep feedlot. Twenty Morada Nova male hair sheep with an average weight of 15.40, were allocated in a randomized block design, with four treatments and five replicates. The experimental treatments consisted of four diets (30% native cacti + 30% shrub hay + 40% concentrate, on dry matter basis: T1- xiquexique + sabiá hay; T2- xiquexique + flor de seda hay; T3- mandacaru + sabiá hay e T4- mandacaru + flor-de-seda hay. The concentrate consisted of 100.0% algaroba (Prosopis juliflora (Sw DC pods. No significant difference was observed for daily weight gain which averaged 88.77 g, and also for voluntary intakes of dry matter, organic matter, ether extract, total carbohydrates, nonfiber carbohydrates, total digestible nutrients and digestible energy in relation to g/day, %BW and g/kg0.75. Significant differences were observed for intake of water in g/day.

  1. A proteomic and metabolomic approach for understanding the role of the flor yeast mitochondria in the velum formation.

    Science.gov (United States)

    Moreno-García, Jaime; García-Martínez, Teresa; Moreno, Juan; Millán, M Carmen; Mauricio, Juan Carlos

    2014-02-17

    Saccharomyces cerevisiae "flor" yeast shows a strong tolerance to high ethanol concentrations and develops a velum (biofilm) on the wine surface after the alcoholic fermentation of grape must. This velum remains along several years during the so called "biological aging" process in the elaboration of some special wines carried out in specific regions around the world and it contributes to the typical organoleptic characteristics of these wines. In order to grow in this condition, flor yeast has to elaborate a response where the mitochondrial function is essential. The objective of this study is to elucidate the role of the mitochondria in the response of a flor yeast, S. cerevisiae G1, growing in a controlled velum formation condition. For this purpose, proteome and metabolome were characterized by comparing data with those from an initial fermentative condition used as reference. The obtained proteomic profiles show more mitochondrial proteins related with the ethanol resistance (13), cell respiration (18), mitochondrial genome maintenance (13), and apoptosis (2) detected under the velum formation condition. Also, the finger-printing obtained by means of the exo-metabolites directly related with the quality of fermented beverages and quantified in the velum condition shows important differences from those obtained in the reference condition. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Structural Equations and Causal Explanations: Some Challenges for Causal SEM

    Science.gov (United States)

    Markus, Keith A.

    2010-01-01

    One common application of structural equation modeling (SEM) involves expressing and empirically investigating causal explanations. Nonetheless, several aspects of causal explanation that have an impact on behavioral science methodology remain poorly understood. It remains unclear whether applications of SEM should attempt to provide complete…

  3. Caracterização florística de bancos de sementes em sistemas de cultivo lavoura-pastagem Floristic characterization of seedbanks under Integrated crop-pasture systems

    Directory of Open Access Journals (Sweden)

    F.S. Ikeda

    2007-12-01

    Full Text Available Avaliou-se o efeito de sistemas de cultivo, preparo do solo e níveis de adubação sobre a composição florística de banco de sementes no solo em áreas submetidas a três sistemas de cultivo (lavoura contínua, lavoura-pastagem-lavoura e pastagem-lavoura-pastagem, dois sistemas de preparo do solo (convencional e semeadura direta e dois níveis de adubação (manutenção e corretiva gradual, e uma área de pastagem contínua com preparo convencional e adubação corretiva gradual. Dessa forma, verificou-se que o sistema de cultivo e o sistema de preparo do solo foram os fatores mais importantes na determinação da estrutura florística dos bancos de sementes. Além disso, a adubação corretiva gradual aumentou o número de famílias e de espécies, em relação à de manutenção.The effect of cultivation systems, tillage and fertilization levels on the floristic composition of seedbanks was evaluated at three cultivation systems (continuous crop, crop-pasture-crop, pasture-crop-pasture, two tillage systems (tillage and no-tillage and two fertilization levels (corrective and maintenance, and a continuous pasture area under no-tillage and corrective fertilization. Cultivation and tillage system were the most important factors affecting the floristic structure of seedbanks. Besides, corrective fertilization increased the number of families and species in relation to maintenance fertilization.

  4. Levantamento florísitico na Estação Ecológica do Tripuí, Ouro Preto, MG Floristic inventory in the Tripuí Ecological Station, Ouro Preto, MG

    Directory of Open Access Journals (Sweden)

    Gilberto Pedralli

    1997-12-01

    Full Text Available Realizou-se o levantamento florístico na Estação Ecológica do Tripuí, Ouro Preto, MG (43º34'33" W e 20º23'45"S. O clima da região é do tipo mesotérmico, com inverno seco (Cwb sg. Köppen e com temperaturas médias oscilando entre 14º e 19ºC. A Estação apresenta como principais tipos vegetacionais as florestas mesófilas estacionais, o cerrado, a vegetação aquática (brejos, lagoa artificial e córregos e as formações sucessionais ('candeial'. Para o levantamento florístico utilizou-se o método de parcelas e coletas por trilhas e caminhos, sendo identificadas 101 famílias, 242 gêneros e 462 espécies. As famílias que apresentaram maior riqueza específica foram Asteraceae (10,82%, Melastomataceae (8,22%, Myrtaceae (7,14% e Rubiaceae (4,76%.A floristic inventory was carried out in Tripuí Ecological Station, Ouro Preto, Minas Gerais state (43º34'33" W and 20º23'45"S. In this region the climate, according to Koppen's classification, is Cwb, i.e., with a mild summer and a dry winter. The main vegetation types identified were semideciduous mesophytic forests, cerrado, aquatic vegetation ('brejos', artificial lake and creeks and secondary formations ('candeial'. Through the floristic inventory in plots, trails and ways were identified 101 families, 242 genera and 462 species. Asteraceae (10,82%, Melastomataceae (8,22%, Myrtaceae (7,14% and Rubiaceae (4,76% were the families with the greatest specific richness.

  5. Expert Causal Reasoning and Explanation.

    Science.gov (United States)

    Kuipers, Benjamin

    The relationship between cognitive psychologists and researchers in artificial intelligence carries substantial benefits for both. An ongoing investigation in causal reasoning in medical problem solving systems illustrates this interaction. This paper traces a dialectic of sorts in which three different types of causal resaoning for medical…

  6. Re-thinking local causality

    NARCIS (Netherlands)

    Friederich, Simon

    There is widespread belief in a tension between quantum theory and special relativity, motivated by the idea that quantum theory violates J. S. Bell's criterion of local causality, which is meant to implement the causal structure of relativistic space-time. This paper argues that if one takes the

  7. Covariation in Natural Causal Induction.

    Science.gov (United States)

    Cheng, Patricia W.; Novick, Laura R.

    1991-01-01

    Biases and models usually offered by cognitive and social psychology and by philosophy to explain causal induction are evaluated with respect to focal sets (contextually determined sets of events over which covariation is computed). A probabilistic contrast model is proposed as underlying covariation computation in natural causal induction. (SLD)

  8. Paradoxical Behavior of Granger Causality

    Science.gov (United States)

    Witt, Annette; Battaglia, Demian; Gail, Alexander

    2013-03-01

    Granger causality is a standard tool for the description of directed interaction of network components and is popular in many scientific fields including econometrics, neuroscience and climate science. For time series that can be modeled as bivariate auto-regressive processes we analytically derive an expression for spectrally decomposed Granger Causality (SDGC) and show that this quantity depends only on two out of four groups of model parameters. Then we present examples of such processes whose SDGC expose paradoxical behavior in the sense that causality is high for frequency ranges with low spectral power. For avoiding misinterpretations of Granger causality analysis we propose to complement it by partial spectral analysis. Our findings are illustrated by an example from brain electrophysiology. Finally, we draw implications for the conventional definition of Granger causality. Bernstein Center for Computational Neuroscience Goettingen

  9. On causality of extreme events

    Directory of Open Access Journals (Sweden)

    Massimiliano Zanin

    2016-06-01

    Full Text Available Multiple metrics have been developed to detect causality relations between data describing the elements constituting complex systems, all of them considering their evolution through time. Here we propose a metric able to detect causality within static data sets, by analysing how extreme events in one element correspond to the appearance of extreme events in a second one. The metric is able to detect non-linear causalities; to analyse both cross-sectional and longitudinal data sets; and to discriminate between real causalities and correlations caused by confounding factors. We validate the metric through synthetic data, dynamical and chaotic systems, and data representing the human brain activity in a cognitive task. We further show how the proposed metric is able to outperform classical causality metrics, provided non-linear relationships are present and large enough data sets are available.

  10. Neural Correlates of Causal Power Judgments

    Directory of Open Access Journals (Sweden)

    Denise Dellarosa Cummins

    2014-12-01

    Full Text Available Causal inference is a fundamental component of cognition and perception. Probabilistic theories of causal judgment (most notably causal Bayes networks derive causal judgments using metrics that integrate contingency information. But human estimates typically diverge from these normative predictions. This is because human causal power judgments are typically strongly influenced by beliefs concerning underlying causal mechanisms, and because of the way knowledge is retrieved from human memory during the judgment process. Neuroimaging studies indicate that the brain distinguishes causal events from mere covariation, and between perceived and inferred causality. Areas involved in error prediction are also activated, implying automatic activation of possible exception cases during causal decision-making.

  11. Clear message for causality

    Energy Technology Data Exchange (ETDEWEB)

    Steinberg, Aephraim M. [Institute for Experimental Physics, University of Vienna, Vienna (Austria)

    2003-12-01

    Experiment confirms that information cannot be transmitted faster than the speed of light. Ever since Einstein stated that nothing can travel faster than light, physicists have delighted in finding exceptions. One after another, observations of such 'superluminal' propagation have been made. However, while some image or pattern- such as the motion of a spotlight projected on a distant wall - might have appeared to travel faster than light, it seemed that there was no way to use the superluminal effect to transmit energy or information. In recent years, the superluminal propagation of light pulses through certain media has led to renewed controversy. In 1995, for example, Guenther Nimtz of the University of Cologne encoded Mozart's 40th Symphony on a microwave beam, which he claimed to have transmitted at a speed faster than light. Others maintain that such a violation of Einstein's speed limit would wreak havoc on our most fundamental ideas about causality, allowing an effect to precede its cause. Relativity teaches us that sending a signal faster than light would be equivalent to sending it backwards in time. (U.K.)

  12. Causal Rasch models

    Directory of Open Access Journals (Sweden)

    A. Jackson Stenner

    2013-08-01

    Full Text Available Rasch’s unidimensional models for measurement show how to connect object measures (e.g., reader abilities, measurement mechanisms (e.g., machine-generated cloze reading items, and observational outcomes (e.g., counts correct on reading instruments. Substantive theory shows what interventions or manipulations to the measurement mechanism can be traded off against a change to the object measure to hold the observed outcome constant. A Rasch model integrated with a substantive theory dictates the form and substance of permissible interventions. Rasch analysis, absent construct theory and an associated specification equation, is a black box in which understanding may be more illusory than not. Finally, the quantitative hypothesis can be tested by comparing theory-based trade-off relations with observed trade-off relations. Only quantitative variables (as measured support such trade-offs. Note that to test the quantitative hypothesis requires more than manipulation of the algebraic equivalencies in the Rasch model or descriptively fitting data to the model. A causal Rasch model involves experimental intervention/manipulation on either reader ability or text complexity or a conjoint intervention on both simultaneously to yield a successful prediction of the resultant observed outcome (count correct. We conjecture that when this type of manipulation is introduced for individual reader text encounters and model predictions are consistent with observations, the quantitative hypothesis is sustained.

  13. Causal Rasch models.

    Science.gov (United States)

    Stenner, A Jackson; Fisher, William P; Stone, Mark H; Burdick, Donald S

    2013-01-01

    Rasch's unidimensional models for measurement show how to connect object measures (e.g., reader abilities), measurement mechanisms (e.g., machine-generated cloze reading items), and observational outcomes (e.g., counts correct on reading instruments). Substantive theory shows what interventions or manipulations to the measurement mechanism can be traded off against a change to the object measure to hold the observed outcome constant. A Rasch model integrated with a substantive theory dictates the form and substance of permissible interventions. Rasch analysis, absent construct theory and an associated specification equation, is a black box in which understanding may be more illusory than not. Finally, the quantitative hypothesis can be tested by comparing theory-based trade-off relations with observed trade-off relations. Only quantitative variables (as measured) support such trade-offs. Note that to test the quantitative hypothesis requires more than manipulation of the algebraic equivalencies in the Rasch model or descriptively fitting data to the model. A causal Rasch model involves experimental intervention/manipulation on either reader ability or text complexity or a conjoint intervention on both simultaneously to yield a successful prediction of the resultant observed outcome (count correct). We conjecture that when this type of manipulation is introduced for individual reader text encounters and model predictions are consistent with observations, the quantitative hypothesis is sustained.

  14. Causal Rasch models

    Science.gov (United States)

    Stenner, A. Jackson; Fisher, William P.; Stone, Mark H.; Burdick, Donald S.

    2013-01-01

    Rasch's unidimensional models for measurement show how to connect object measures (e.g., reader abilities), measurement mechanisms (e.g., machine-generated cloze reading items), and observational outcomes (e.g., counts correct on reading instruments). Substantive theory shows what interventions or manipulations to the measurement mechanism can be traded off against a change to the object measure to hold the observed outcome constant. A Rasch model integrated with a substantive theory dictates the form and substance of permissible interventions. Rasch analysis, absent construct theory and an associated specification equation, is a black box in which understanding may be more illusory than not. Finally, the quantitative hypothesis can be tested by comparing theory-based trade-off relations with observed trade-off relations. Only quantitative variables (as measured) support such trade-offs. Note that to test the quantitative hypothesis requires more than manipulation of the algebraic equivalencies in the Rasch model or descriptively fitting data to the model. A causal Rasch model involves experimental intervention/manipulation on either reader ability or text complexity or a conjoint intervention on both simultaneously to yield a successful prediction of the resultant observed outcome (count correct). We conjecture that when this type of manipulation is introduced for individual reader text encounters and model predictions are consistent with observations, the quantitative hypothesis is sustained. PMID:23986726

  15. Causal aspects of diffraction

    International Nuclear Information System (INIS)

    Crawford, G.N.

    1981-01-01

    The analysis is directed at a causal description of photon diffraction, which is explained in terms of a wave exerting real forces and providing actual guidance to each quantum of energy. An undulatory PSI wave is associated with each photon, and this wave is assumed to imply more than an informative probability function, so that it actually carries real energy, in much the same way as does an electro-magnetic wave. Whether or not it may be in some way related to the electromagnetic wave is left as a matter of on-going concern. A novel application of the concept of a minimum energy configuration is utilized; that is, a system of energy quanta seeks out relative positions and orientations of least mutual energy, much as an electron seeks its Bohr radius as a position of least mutual energy. Thus the concept implies more a guiding interaction of the PSI waves than an interfering cancellation of these waves. Similar concepts have been suggested by L. de Broglie and D. Bohm

  16. ["Karoshi" and causal relationships].

    Science.gov (United States)

    Hamajima, N

    1992-08-01

    This paper aims to introduce a measure for use by physicians for stating the degree of probable causal relationship for "Karoshi", ie, a sudden death from cerebrovascular diseases or ischemic heart diseases under occupational stresses, as well as to give a brief description for legal procedures associated with worker's compensation and civil trial in Japan. It is a well-used measure in epidemiology, "attributable risk percent (AR%)", which can be applied to describe the extent of contribution to "Karoshi" of the excess occupational burdens the deceased worker was forced to bear. Although several standards such as average occupational burdens for the worker, average occupational burdens for an ordinary worker, burdens in a nonoccupational life, and a complete rest, might be considered for the AR% estimation, the average occupational burdens for an ordinary worker should normally be utilized as a standard for worker's compensation. The adoption of AR% could be helpful for courts to make a consistent judgement whether "Karoshi" cases are compensatable or not.

  17. Structure and Strength in Causal Induction

    Science.gov (United States)

    Griffiths, Thomas L.; Tenenbaum, Joshua B.

    2005-01-01

    We present a framework for the rational analysis of elemental causal induction--learning about the existence of a relationship between a single cause and effect--based upon causal graphical models. This framework makes precise the distinction between causal structure and causal strength: the difference between asking whether a causal relationship…

  18. FlorNExT®, a cloud computing application to estimate growth and yield of maritime pine (Pinus pinaster Ait.) stands in Northeastern Portugal

    Energy Technology Data Exchange (ETDEWEB)

    Barreiro, S.; Rua, J.; Tomé, M.

    2016-07-01

    Aim of the study. To introduce and describe FlorNExT®, a free cloud computing application to estimate growth and yield of maritime pine (Pinus pinaster Ait.) even-aged stands in the Northeast of Portugal (NE Portugal). Area of study: NE Portugal. Material and methods: FlorNExT® implements a dynamic growth and yield modelling framework which integrates transition functions for dominant height (site index curves) and basal area, as well as output functions for tree and stand volume, biomass, and carbon content. Main results: FlorNExT® is freely available from any device with an Internet connection at: http://flornext.esa.ipb.pt/. Research highlights: This application has been designed to make it possible for any stakeholder to easily estimate standing volume, biomass, and carbon content in maritime pine stands from stand data, as well as to estimate growth and yield based on four stand variables: age, density, dominant height, and basal area. FlorNExT® allows planning thinning treatments. FlorNExT® is a fundamental tool to support forest mobilization at local and regional scales in NE Portugal. (Author)

  19. FlorNExT®, a cloud computing application to estimate growth and yield of maritime pine (Pinus pinaster Ait. stands in Northeastern Portugal

    Directory of Open Access Journals (Sweden)

    Fernando Pérez-Rodríguez

    2016-07-01

    Full Text Available Aim of the study: To introduce and describe FlorNExT®, a free cloud computing application to estimate growth and yield of maritime pine (Pinus pinaster Ait. even-aged stands in the Northeast of Portugal (NE Portugal. Area of study: NE Portugal. Material and methods: FlorNExT® implements a dynamic growth and yield modelling framework which integrates transition functions for dominant height (site index curves and basal area, as well as output functions for tree and stand volume, biomass, and carbon content. Main results: FlorNExT® is freely available from any device with an Internet connection at: http://flornext.esa.ipb.pt/. Research highlights: This application has been designed to make it possible for any stakeholder to easily estimate standing volume, biomass, and carbon content in maritime pine stands from stand data, as well as to estimate growth and yield based on four stand variables: age, density, dominant height, and basal area. FlorNExT® allows planning thinning treatments. FlorNExT® is a fundamental tool to support forest mobilization at local and regional scales in NE Portugal. Keywords: forest management; maritime pine; forest modelling; knowledge transfer tool.

  20. Dynamics of Quantum Causal Structures

    Science.gov (United States)

    Castro-Ruiz, Esteban; Giacomini, Flaminia; Brukner, Časlav

    2018-01-01

    It was recently suggested that causal structures are both dynamical, because of general relativity, and indefinite, because of quantum theory. The process matrix formalism furnishes a framework for quantum mechanics on indefinite causal structures, where the order between operations of local laboratories is not definite (e.g., one cannot say whether operation in laboratory A occurs before or after operation in laboratory B ). Here, we develop a framework for "dynamics of causal structures," i.e., for transformations of process matrices into process matrices. We show that, under continuous and reversible transformations, the causal order between operations is always preserved. However, the causal order between a subset of operations can be changed under continuous yet nonreversible transformations. An explicit example is that of the quantum switch, where a party in the past affects the causal order of operations of future parties, leading to a transition from a channel from A to B , via superposition of causal orders, to a channel from B to A . We generalize our framework to construct a hierarchy of quantum maps based on transformations of process matrices and transformations thereof.

  1. Dynamics of Quantum Causal Structures

    Directory of Open Access Journals (Sweden)

    Esteban Castro-Ruiz

    2018-03-01

    Full Text Available It was recently suggested that causal structures are both dynamical, because of general relativity, and indefinite, because of quantum theory. The process matrix formalism furnishes a framework for quantum mechanics on indefinite causal structures, where the order between operations of local laboratories is not definite (e.g., one cannot say whether operation in laboratory A occurs before or after operation in laboratory B. Here, we develop a framework for “dynamics of causal structures,” i.e., for transformations of process matrices into process matrices. We show that, under continuous and reversible transformations, the causal order between operations is always preserved. However, the causal order between a subset of operations can be changed under continuous yet nonreversible transformations. An explicit example is that of the quantum switch, where a party in the past affects the causal order of operations of future parties, leading to a transition from a channel from A to B, via superposition of causal orders, to a channel from B to A. We generalize our framework to construct a hierarchy of quantum maps based on transformations of process matrices and transformations thereof.

  2. Principal stratification in causal inference.

    Science.gov (United States)

    Frangakis, Constantine E; Rubin, Donald B

    2002-03-01

    Many scientific problems require that treatment comparisons be adjusted for posttreatment variables, but the estimands underlying standard methods are not causal effects. To address this deficiency, we propose a general framework for comparing treatments adjusting for posttreatment variables that yields principal effects based on principal stratification. Principal stratification with respect to a posttreatment variable is a cross-classification of subjects defined by the joint potential values of that posttreatment variable tinder each of the treatments being compared. Principal effects are causal effects within a principal stratum. The key property of principal strata is that they are not affected by treatment assignment and therefore can be used just as any pretreatment covariate. such as age category. As a result, the central property of our principal effects is that they are always causal effects and do not suffer from the complications of standard posttreatment-adjusted estimands. We discuss briefly that such principal causal effects are the link between three recent applications with adjustment for posttreatment variables: (i) treatment noncompliance, (ii) missing outcomes (dropout) following treatment noncompliance. and (iii) censoring by death. We then attack the problem of surrogate or biomarker endpoints, where we show, using principal causal effects, that all current definitions of surrogacy, even when perfectly true, do not generally have the desired interpretation as causal effects of treatment on outcome. We go on to forrmulate estimands based on principal stratification and principal causal effects and show their superiority.

  3. Discrete causal theory emergent spacetime and the causal metric hypothesis

    CERN Document Server

    Dribus, Benjamin F

    2017-01-01

    This book evaluates and suggests potentially critical improvements to causal set theory, one of the best-motivated approaches to the outstanding problems of fundamental physics. Spacetime structure is of central importance to physics beyond general relativity and the standard model. The causal metric hypothesis treats causal relations as the basis of this structure. The book develops the consequences of this hypothesis under the assumption of a fundamental scale, with smooth spacetime geometry viewed as emergent. This approach resembles causal set theory, but differs in important ways; for example, the relative viewpoint, emphasizing relations between pairs of events, and relationships between pairs of histories, is central. The book culminates in a dynamical law for quantum spacetime, derived via generalized path summation.

  4. Causal boundary for stably causal space-times

    International Nuclear Information System (INIS)

    Racz, I.

    1987-12-01

    The usual boundary constructions for space-times often yield an unsatisfactory boundary set. This problem is reviewed and a new solution is proposed. An explicit identification rule is given on the set of the ideal points of the space-time. This construction leads to a satisfactory boundary point set structure for stably causal space-times. The topological properties of the resulting causal boundary construction are examined. For the stably causal space-times each causal curve has a unique endpoint on the boundary set according to the extended Alexandrov topology. The extension of the space-time through the boundary is discussed. To describe the singularities the defined boundary sets have to be separated into two disjoint sets. (D.Gy.) 8 refs

  5. Causal boundary for strongly causal spacetimes: Pt. 1

    International Nuclear Information System (INIS)

    Szabados, L.B.

    1989-01-01

    In a previous paper an analysis of the general structure of the causal boundary constructions and a new explicit identification rule, built up from elementary TIP-TIF gluings, were presented. In the present paper we complete our identification by incorporating TIP-TIP and TIF-TIF gluings as well. An asymptotic causality condition is found which, for physically important cases, ensures the uniqueness of the endpoints of the non-spacelike curves in the completed spacetime. (author)

  6. Classical planning and causal implicatures

    DEFF Research Database (Denmark)

    Blackburn, Patrick Rowan; Benotti, Luciana

    In this paper we motivate and describe a dialogue manager (called Frolog) which uses classical planning to infer causal implicatures. A causal implicature is a type of Gricean relation implicature, a highly context dependent form of inference. As we shall see, causal implicatures are important...... to generate clarification requests"; as a result we can model task-oriented dialogue as an interactive process locally structured by negotiation of the underlying task. We give several examples of Frolog-human dialog, discuss the limitations imposed by the classical planning paradigm, and indicate...

  7. Functional equations with causal operators

    CERN Document Server

    Corduneanu, C

    2003-01-01

    Functional equations encompass most of the equations used in applied science and engineering: ordinary differential equations, integral equations of the Volterra type, equations with delayed argument, and integro-differential equations of the Volterra type. The basic theory of functional equations includes functional differential equations with causal operators. Functional Equations with Causal Operators explains the connection between equations with causal operators and the classical types of functional equations encountered by mathematicians and engineers. It details the fundamentals of linear equations and stability theory and provides several applications and examples.

  8. Composição florística de florestas estacionais ribeirinhas no estado de Mato Grosso do Sul, Brasil Floristic composition of seasonal riparian forests in Mato Grosso do Sul state, Brazil

    Directory of Open Access Journals (Sweden)

    Vivian Ribeiro Baptista-Maria

    2009-06-01

    Full Text Available O presente estudo teve como objetivos caracterizar a composição florística em dois trechos de floresta estacional semidecidual associada ao rio Formoso, Bonito, MS, e em três trechos de florestas estacionais deciduais e semideciduais associadas aos rios Salobra, Salobrinha e Perdido ocorrentes no Parque Nacional da Serra da Bodoquena (76.481 ha - única unidade de Conservação Federal de Proteção Integral implantada no Estado de Mato Grosso do Sul. O levantamento florístico foi realizado mensalmente entre o período de outubro/2004 a março/2006, onde foram coletadas fanerógamas em fase reprodutiva (flores e frutos, através do método de tempo de avaliação. O levantamento florístico resultou em 56 famílias, 184 gêneros e 307 espécies. Do total das espécies, 68% apresentaram hábito arbóreo, 17% arbustos, 14% foram lianas e apenas 1% palmeiras. A família Fabaceae (Leguminosae, representada por 51 (16,6% espécies, foi a de maior riqueza. Os resultados obtidos neste trabalho contribuíram para o conhecimento da flora sul-mato-grossense e sua distribuição geográfica, reforçando a necessidade de conservação destas matas ribeirinhas e fornecendo subsídios para os planos de restauração das áreas degradadas do entorno da unidade de conservação e das áreas de proteção permanente (APP's dos rios ocorrentes na região.This study aimed to characterize the floristic composition in two stretches of seasonal semideciduous forest associated with the Formoso River, Bonito, Mato Grosso do Sul State, and in three stretches of seasonal deciduous and semideciduous forests associated with the Salobra, Salobrinha and Perdido rivers in Bodoquena Plateau National Park (76,481 ha - the only Federal Conservation unit with Integral Protection in the state of Mato Grosso do Sul. The floristic survey was carried out monthly from October/2004 to March/2006, where flowering and fruiting phanerogams were collected by the method of evaluation

  9. Causal Modelling in Evaluation Research.

    Science.gov (United States)

    Winteler, Adolf

    1983-01-01

    A study applied path analysis methods, using new techniques of causal analysis, to the problem of predicting the achievement, dropout rate, and satisfaction of university students. Besides providing explanations, the technique indicates possible remedial measures. (MSE)

  10. Consciousness and the "Causal Paradox"

    OpenAIRE

    Velmans, Max

    1996-01-01

    Viewed from a first-person perspective consciousness appears to be necessary for complex, novel human activity - but viewed from a third-person perspective consciousness appears to play no role in the activity of brains, producing a "causal paradox". To resolve this paradox one needs to distinguish consciousness of processing from consciousness accompanying processing or causing processing. Accounts of consciousness/brain causal interactions switch between first- and third-person perspectives...

  11. Diversidad florística del Paisaje Natural Protegido “Estrella-Aguadores”, Santiago de Cuba, Cuba

    Directory of Open Access Journals (Sweden)

    Miguel Ángel Castell-Puchades

    2016-07-01

    Full Text Available El Paisaje Natural Protegido “Estrella-Aguadores” se considera entre las áreas de mayor riqueza florística de la costa suroriental de Cuba, sin embargo, son insuficientes los estudios florísticos locales que les posibilite a técnicos y decisores locales contar con la información necesaria para emprender acciones adecuadas de conservación y manejo; con el objetivo de resolver este problema, realizamos un estudio de la diversidad florística que caracteriza el área protegida. Se desarrolló un muestreo preferencial, sin rumbo fijo, teniendo en cuenta en cada recorrido las características físico-geográficas del área, así como la ecología de las especies. El trabajo de campo se realizó según la metodología de los inventarios biológicos rápidos. Se identifican 266 especies de angiospermas para el Paisaje Natural Protegido “Estrella-Aguadores”, de las cuales 112 constituyen nuevos registros para el área protegida. Se registran 38 especies endémicas y seis especies amenazadas. El 48% de las angiospermas registradas presentan algún tipo de uso o valor para los comunitarios. Este trabajo muestra al Paisaje Natural Protegido “Estrella-Aguadores” como una de las reservas más importantes en diversidad de angiospermas de las terrazas costeras de Cuba, lo cual resalta su función como área de protección de la flora.

  12. Composição florística e estrutura de uma unidade de manejo florestal sustentável na Floresta Nacional do Tapajós, Pará Floristic composition and structure of a sustainable forest management unit at Tapajos National Forest, Para, Brazil

    Directory of Open Access Journals (Sweden)

    Fábio Guimarães Gonçalves

    2008-01-01

    Full Text Available Neste trabalho são discutidos aspectos da composição florística e da estrutura de um povoamento de floresta ombrófila densa submetido a práticas de exploração madeireira de impacto reduzido. O estudo foi conduzido numa unidade de manejo florestal com aproximadamente 3.200 ha, instalada na porção norte da Floresta Nacional do Tapajós (estado do Pará, onde foram extraídos, em média, 23,7 m³ de madeira por hectare. Para representar a variabilidade existente na área experimental, foram estabelecidas aleatoriamente seis parcelas amostrais de um hectare em diferentes quadras de exploração. As análises florístico-estruturais foram realizadas em duas escalas distintas com vistas a atender objetivos específicos: (a em nível de unidade de manejo, para uma caracterização global do povoamento florestal no qual serão baseados estudos subseqüentes; e (b em nível de parcela amostral, para subsidiar o estudo de dados de sensoriamento remoto frente às variações florístico-estruturais observadas. O conjunto de resultados obtidos indicou que a unidade de manejo florestal apresenta uma elevada diversidade florística no componente arbóreo (índice de Shannon-Weaver igual a 4,22. Observou-se que o povoamento é caracterizado pela concentração de uma grande quantidade de indivíduos e espécies em poucas famílias botânicas e por um número elevado de espécies localmente raras. A análise das variações florístico-estruturais entre parcelas amostrais evidenciou diferenças estatísticas significativas quanto à diversidade e a similaridade de espécies e quanto a valores médios de altura total. Adicionalmente, observou-se certa variabilidade nos padrões estruturais em termos de distribuição diamétrica e de valores estimados de volume comercial de madeira.In this work we discuss aspects of the floristic composition and structure of a stand of dense tropical rain forest subjected to low-impact logging practices. We conducted

  13. Evolución de la composición florística Post-fuego en un carrascal de Navarra (n de España

    Directory of Open Access Journals (Sweden)

    Cavero, R. Y.

    1999-12-01

    Full Text Available This paper presents results about floristic composition dynamics during four years after controlled fires in a Mediterranean pin-oak wood in Navarra (N Spain. The samples have been taken from eight permanent 1 m2 plots subjected to different treatments: different fire type, different situation on the field, and with or without not fired soil addition. The regeneration strategies of the species and the influence of the different treatments on the flora are analyzed. The floristic composition dynamics follows a general model: the species began to appear progressively. The number of species grows gradually to reach a maximum between one and three years after the fire. Later, the number of species diminishes. Post fire species are those that existed before the fire, that is to say, there is an autosuccession process.

    [es] Se presentan los resultados de cuatro años de estudio sobre la evolución de la composición florística de un carrascal mediterráneo sometido a fuegos controlados en Navarra (N de España. Los muestreos se han llevado a cabo en ocho cuadrados permanentes de 1 m2 de superficie, cada uno sometido a distinto tratamiento: distinto tipo de fuego, distinta situación en la parcela y adición o no de suelo no quemado. Se analizan la estrategia de regeneración de las especies que aparecen después de los fuegos y la influencia de los tratamientos en la regeneración de la flora. La evolución de la composición florística sigue un modelo general: las especies empiezan a aparecer progresivamente, su número crece hasta obtener un máximo entre el año y los cuatro años después de los fuegos, a partir del cual disminuye. Las especies que aparecen son las mismas que había previamente, es decir, se da un proceso de autosucesión. [fr] On présente les résultats de quatre ans d'étude sur l'évolution de la composition floristique d'un bois de chêne vert méditerranéen soumis à des feux contr

  14. Regression to Causality : Regression-style presentation influences causal attribution

    DEFF Research Database (Denmark)

    Bordacconi, Mats Joe; Larsen, Martin Vinæs

    2014-01-01

    of equivalent results presented as either regression models or as a test of two sample means. Our experiment shows that the subjects who were presented with results as estimates from a regression model were more inclined to interpret these results causally. Our experiment implies that scholars using regression...... models – one of the primary vehicles for analyzing statistical results in political science – encourage causal interpretation. Specifically, we demonstrate that presenting observational results in a regression model, rather than as a simple comparison of means, makes causal interpretation of the results...... more likely. Our experiment drew on a sample of 235 university students from three different social science degree programs (political science, sociology and economics), all of whom had received substantial training in statistics. The subjects were asked to compare and evaluate the validity...

  15. Putting a cap on causality violations in causal dynamical triangulations

    International Nuclear Information System (INIS)

    Ambjoern, Jan; Loll, Renate; Westra, Willem; Zohren, Stefan

    2007-01-01

    The formalism of causal dynamical triangulations (CDT) provides us with a non-perturbatively defined model of quantum gravity, where the sum over histories includes only causal space-time histories. Path integrals of CDT and their continuum limits have been studied in two, three and four dimensions. Here we investigate a generalization of the two-dimensional CDT model, where the causality constraint is partially lifted by introducing branching points with a weight g s , and demonstrate that the system can be solved analytically in the genus-zero sector. The solution is analytic in a neighborhood around weight g s = 0 and cannot be analytically continued to g s = ∞, where the branching is entirely geometric and where one would formally recover standard Euclidean two-dimensional quantum gravity defined via dynamical triangulations or Liouville theory

  16. Bayesian networks improve causal environmental ...

    Science.gov (United States)

    Rule-based weight of evidence approaches to ecological risk assessment may not account for uncertainties and generally lack probabilistic integration of lines of evidence. Bayesian networks allow causal inferences to be made from evidence by including causal knowledge about the problem, using this knowledge with probabilistic calculus to combine multiple lines of evidence, and minimizing biases in predicting or diagnosing causal relationships. Too often, sources of uncertainty in conventional weight of evidence approaches are ignored that can be accounted for with Bayesian networks. Specifying and propagating uncertainties improve the ability of models to incorporate strength of the evidence in the risk management phase of an assessment. Probabilistic inference from a Bayesian network allows evaluation of changes in uncertainty for variables from the evidence. The network structure and probabilistic framework of a Bayesian approach provide advantages over qualitative approaches in weight of evidence for capturing the impacts of multiple sources of quantifiable uncertainty on predictions of ecological risk. Bayesian networks can facilitate the development of evidence-based policy under conditions of uncertainty by incorporating analytical inaccuracies or the implications of imperfect information, structuring and communicating causal issues through qualitative directed graph formulations, and quantitatively comparing the causal power of multiple stressors on value

  17. Causality and analyticity in optics

    International Nuclear Information System (INIS)

    Nussenzveig, H.M.

    In order to provide an overall picture of the broad range of optical phenomena that are directly linked with the concepts of causality and analyticity, the following topics are briefly reviewed, emphasizing recent developments: 1) Derivation of dispersion relations for the optical constants of general linear media from causality. Application to the theory of natural optical activity. 2) Derivation of sum rules for the optical constants from causality and from the short-time response function (asymptotic high-frequency behavior). Average spectral behavior of optical media. Applications. 3) Role of spectral conditions. Analytic properties of coherence functions in quantum optics. Reconstruction theorem.4) Phase retrieval problems. 5) Inverse scattering problems. 6) Solution of nonlinear evolution equations in optics by inverse scattering methods. Application to self-induced transparency. Causality in nonlinear wave propagation. 7) Analytic continuation in frequency and angular momentum. Complex singularities. Resonances and natural-mode expansions. Regge poles. 8) Wigner's causal inequality. Time delay. Spatial displacements in total reflection. 9) Analyticity in diffraction theory. Complex angular momentum theory of Mie scattering. Diffraction as a barrier tunnelling effect. Complex trajectories in optics. (Author) [pt

  18. Hierarchical organisation of causal graphs

    International Nuclear Information System (INIS)

    Dziopa, P.

    1993-01-01

    This paper deals with the design of a supervision system using a hierarchy of models formed by graphs, in which the variables are the nodes and the causal relations between the variables of the arcs. To obtain a representation of the variables evolutions which contains only the relevant features of their real evolutions, the causal relations are completed with qualitative transfer functions (QTFs) which produce roughly the behaviour of the classical transfer functions. Major improvements have been made in the building of the hierarchical organization. First, the basic variables of the uppermost level and the causal relations between them are chosen. The next graph is built by adding intermediary variables to the upper graph. When the undermost graph has been built, the transfer functions parameters corresponding to its causal relations are identified. The second task consists in the upwelling of the information from the undermost graph to the uppermost one. A fusion procedure of the causal relations has been designed to compute the QFTs relevant for each level. This procedure aims to reduce the number of parameters needed to represent an evolution at a high level of abstraction. These techniques have been applied to the hierarchical modelling of nuclear process. (authors). 8 refs., 12 figs

  19. Florística, estrutura e características do solo de um fragmento de floresta paludosa no sudeste do Brasil Floristics, structure and soil characteristics of a swamp forest fragment, in southeast Brazil

    Directory of Open Access Journals (Sweden)

    Laércio Loures

    2007-12-01

    Full Text Available Realizou-se o levantamento da comunidade arbórea de uma floresta semidecidual montana ribeirinha, situada no alto Rio Pardo, Santa Rita de Caldas, Minas Gerais (altitude 1.156 a 1.203 m, com o objetivo de avaliar as variações estruturais e variáveis ambientais relacionadas ao substrato. Foram analisadas a densidade, área basal e distribuição de tamanho das árvores e a composição florística da comunidade. Foram alocadas 25 parcelas de 10x40 m para amostragem dos indivíduos arbóreos com diâmetro à altura do peito > 5 cm. Também foram coletados dados topográficos e amostras do solo para análises químicas e texturais. Foram registrados 2.982 indivíduos, 50 famílias, 78 gêneros e 110 espécies. Foram verificados três subgrupos de solos (Organossolos, Gleissolos Melânicos e Gleissolos Háplicos, distribuídos em seqüência, acompanhando o curso do riacho. A comunidade arbórea apresentou uma composição florística e estrutural diferente das florestas paludosas e aluviais do Sudeste e Sul do Brasil, em altitudes menores. Uma análise de correspondência canônica detectou um gradiente de distribuição das espécies arbóreas, principalmente correlacionadas com as variações de argila e de cota altimétrica.A survey of the tree community was conducted for an upland semideciduous riparian forest, located on the upper Rio Pardo, Santa Rita de Caldas, Minas Gerais (1156 to 1203 m altitude, in order to evaluate structural variation and environmental variables associated with the substrate. Density, basal area, tree size distribution and floristic composition were evaluated. In 25 10x40 m plots, all trees with dbh > 5 cm were sampled, topographical aspects were determined and soil samples were collected for chemical and textural analyses. A total of 2982 individuals from 50 families, 78 genera and 110 species were recorded. A sequence of three soil subgroups (Organosoil, Melanic Gleisoil and Haplic Gleisoil was registered in a

  20. Ecologia da vegetação de orla de bosque de carvalho-negral na Serra da Nogueira, Bragança, Portugal

    OpenAIRE

    Rocha, S.; Aguiar, Carlos; Azevedo, João

    2006-01-01

    Avaliou-se o efeito do gradiente "distância à orla" na estrutura e composição florística de dois bosques de Quercus pyrenaica na Serra da Nogueira, Bragança, Portugal. Em cada bosque estabeleceram-se 8 transectos de 40 m com início na orla do bosque e orientados perpendicularmente a esta. Em cada transecto estabeleceram-se bandas de amostragem de 1 x 10 m dispostas perpendiculares aos transactos a 0, 1, 5, 10,20 e 40 m da orla do bosque. Nestas bandas avaliaram-se a composição flo...

  1. Entropy for theories with indefinite causal structure

    International Nuclear Information System (INIS)

    Markes, Sonia; Hardy, Lucien

    2011-01-01

    Any theory with definite causal structure has a defined past and future, be it defined by light cones or an absolute time scale. Entropy is a concept that has traditionally been reliant on a definite notion of causality. However, without a definite notion of causality, the concept of entropy is not all lost. Indefinite causal structure results from combining probabilistic predictions and dynamical space-time. The causaloid framework lays the mathematical groundwork to be able to treat indefinite causal structure. In this paper, we build on the causaloid mathematics and define a causally-unbiased entropy for an indefinite causal structure. In defining a causally-unbiased entropy, there comes about an emergent idea of causality in the form of a measure of causal connectedness, termed the Q factor.

  2. FLO11 gene length and transcriptional level affect biofilm-forming ability of wild flor strains of Saccharomyces cerevisiae.

    Science.gov (United States)

    Zara, Giacomo; Zara, Severino; Pinna, Claudia; Marceddu, Salvatore; Budroni, Marilena

    2009-12-01

    In Saccharomyces cerevisiae, FLO11 encodes an adhesin that is associated with different phenotypes, such as adherence to solid surfaces, hydrophobicity, mat and air-liquid biofilm formation. In the present study, we analysed FLO11 allelic polymorphisms and FLO11-associated phenotypes of 20 flor strains. We identified 13 alleles of different lengths, varying from 3.0 to 6.1 kb, thus demonstrating that FLO11 is highly polymorphic. Two alleles of 3.1 and 5.0 kb were cloned into strain BY4742 to compare the FLO11-associated phenotypes in the same genetic background. We show that there is a significant correlation between biofilm-forming ability and FLO11 length both in different and in the same genetic backgrounds. Moreover, we propose a multiple regression model that allows prediction of air-liquid biofilm-forming ability on the basis of transcription levels and lengths of FLO11 alleles in a population of S. cerevisiae flor strains. Considering that transcriptional differences are only partially explained by the differences in the promoter sequences, our results are consistent with the hypothesis that FLO11 transcription levels are strongly influenced by genetic background and affect biofilm-forming ability.

  3. mediation: R package for causal mediation analysis

    OpenAIRE

    Tingley, Dustin; Yamamoto, Teppei; Hirose, Kentaro; Keele, Luke; Imai, Kosuke

    2012-01-01

    In this paper, we describe the R package mediation for conducting causal mediation analysis in applied empirical research. In many scientific disciplines, the goal of researchers is not only estimating causal effects of a treatment but also understanding the process in which the treatment causally affects the outcome. Causal mediation analysis is frequently used to assess potential causal mechanisms. The mediation package implements a comprehensive suite of statistical tools for conducting su...

  4. A Causal Theory of Modality

    Directory of Open Access Journals (Sweden)

    José Tomás Alvarado

    2009-08-01

    Full Text Available This work presents a causal conception of metaphysical modality in which a state of affairs is metaphysically possible if and only if it can be caused (in the past, the present or the future by current entities. The conception is contrasted with what is called the “combinatorial” conception of modality, in which everything can co-exist with anything else. This work explains how the notion of ‘causality’ should be construed in the causal theory, what difference exists between modalities thus defined from nomological modality, how accessibility relations between possible worlds should be interpreted, and what is the relation between the causal conception and the necessity of origin.

  5. Introductive remarks on causal inference

    Directory of Open Access Journals (Sweden)

    Silvana A. Romio

    2013-05-01

    Full Text Available One of the more challenging issues in epidemiological research is being able to provide an unbiased estimate of the causal exposure-disease effect, to assess the possible etiological mechanisms and the implication for public health. A major source of bias is confounding, which can spuriously create or mask the causal relationship. In the last ten years, methodological research has been developed to better de_ne the concept of causation in epidemiology and some important achievements have resulted in new statistical models. In this review, we aim to show how a technique the well known by statisticians, i.e. standardization, can be seen as a method to estimate causal e_ects, equivalent under certain conditions to the inverse probability treatment weight procedure.

  6. Causal reasoning with mental models

    Science.gov (United States)

    Khemlani, Sangeet S.; Barbey, Aron K.; Johnson-Laird, Philip N.

    2014-01-01

    This paper outlines the model-based theory of causal reasoning. It postulates that the core meanings of causal assertions are deterministic and refer to temporally-ordered sets of possibilities: A causes B to occur means that given A, B occurs, whereas A enables B to occur means that given A, it is possible for B to occur. The paper shows how mental models represent such assertions, and how these models underlie deductive, inductive, and abductive reasoning yielding explanations. It reviews evidence both to corroborate the theory and to account for phenomena sometimes taken to be incompatible with it. Finally, it reviews neuroscience evidence indicating that mental models for causal inference are implemented within lateral prefrontal cortex. PMID:25389398

  7. Causal reasoning with mental models.

    Science.gov (United States)

    Khemlani, Sangeet S; Barbey, Aron K; Johnson-Laird, Philip N

    2014-01-01

    This paper outlines the model-based theory of causal reasoning. It postulates that the core meanings of causal assertions are deterministic and refer to temporally-ordered sets of possibilities: A causes B to occur means that given A, B occurs, whereas A enables B to occur means that given A, it is possible for B to occur. The paper shows how mental models represent such assertions, and how these models underlie deductive, inductive, and abductive reasoning yielding explanations. It reviews evidence both to corroborate the theory and to account for phenomena sometimes taken to be incompatible with it. Finally, it reviews neuroscience evidence indicating that mental models for causal inference are implemented within lateral prefrontal cortex.

  8. Causal reasoning with mental models

    Directory of Open Access Journals (Sweden)

    Sangeet eKhemlani

    2014-10-01

    Full Text Available This paper outlines the model-based theory of causal reasoning. It postulates that the core meanings of causal assertions are deterministic and refer to temporally-ordered sets of possibilities: A causes B to occur means that given A, B occurs, whereas A enables B to occur means that given A, it is possible for B to occur. The paper shows how mental models represent such assertions, and how these models underlie deductive, inductive, and abductive reasoning yielding explanations. It reviews evidence both to corroborate the theory and to account for phenomena sometimes taken to be incompatible with it. Finally, it reviews neuroscience evidence indicating that mental models for causal inference are implemented within lateral prefrontal cortex.

  9. RELACIONES HÍDRICAS Y TEMPERATURAS ALTAS EN FRIJOL DEL TIPO "FLOR DE MAYO"

    Directory of Open Access Journals (Sweden)

    Edwin Javier Barrios-Gómez

    2011-01-01

    Full Text Available Se estudió el efecto del déficit hídrico del suelo y temperatura alta del aire en las relaciones hídricas y temperatura del dosel del cultivo (Tc, rendimiento de semilla (RS y sus componentes en 8 variedades de frijol del tipo "Flor de Mayo" (FM y una variedad criolla. Se realizaron 3 experimentos de campo; Montecillo en riego (MR con la aplicación de agua de la siembra a la madurez, Montecillo en secano (MS con la lluvia como fuente única de humedad y Celaya en secano (CS con lluvia y 2 riegos suplementarios en floración. Se utilizó una dosis de fertilización de 80 kg.ha-1 de nitrógeno y 40 kg.ha-1 de fósforo. En MR el potencial hídrico foliar ( =-0,33 Mpa, osmótico ( =-1,26 Mpa y de turgencia y (P=0,93 Mpa fue más alto que en CS ( =-0,77, =-1,36 y P=0,59 Mpa y MS ( =-1,22, =-1,57 y P=0,35 Mpa; MS, con mayor deficiencia hídrica del suelo, tuvo mayor reducción en y , y mayor grado de ajuste osmótico (AO=0,70 Mpa. El AO estuvo positiva y significativamente asociado con RS y biomasa aérea final (BMAF en los 2 ambientes de secano. La Tc en MR (26,7°C fue más baja que en CS (30,8°C y MS (36,6°C; el estrés por calor se agudizó con el descenso en el contenido hídrico de las plantas en el ambiente más seco (MS; Tc se relacionó negativa y significativamente con y en MS. La alta Tc también tuvo efecto significativo en la producción de BMAF y RS y sus componentes; la alta Tc redujo el RS, BMAF, número de vainas normales.m-2 (VN.m-2 y peso de 100 semillas (P100S en 12,5, 10,7, 10,2 y 3,4% por cada ºC (-1 ºC de aumento en la Tc, respectivamente.

  10. ADAPTABILITY OF THE FLOR DE JUNIO BEAN TYPE AT DIFFERENT ENVIRONMENTS IN MEXICO

    Directory of Open Access Journals (Sweden)

    Jorge Alberto Acosta-Gallegos

    2012-08-01

    Full Text Available Se determinó el rendimiento de 14 líneas y dos variedades comerciales de frijol tipo Flor de Junio en ambientes de temporal y riego del centro de México con el objetivo de identificar líneas de alto rendimiento con baja interacción genotipo x ambiente. El ensayo se estableció en 15 ambientes (combinación localidad/año bajo un diseño experimental de Látice 4x4 con cuatro repeticiones. En los ambientes de temporal la siembra se realizó en julio después de la ocurrencia de lluvias, y en las de riego en noviembre y febrero dependiendo de la localidad; a cada combinación de localidad y año se consideró como un ambiente. Con la información del rendimiento se realizó un análisis por localidad y uno combinado para determinar la importancia de cada factor, a su vez, para determinar los efectos de la interacción genotipo x ambiente (IGA se utilizó el modelo AMMI. En el análisis combinado el 70.4 % de la variación se debió al efecto del ambiente, seguido por el efecto de IGA con el 11.8 % y en tercer lugar se ubicó el factor genotipo. Las líneas con alto rendimiento medio fueron FJB 08061, FJB 08054 y FJB 08004, con 1800 kg ha-1, rendimiento apenas superior al de los testigos que produjeron un mayor rendimiento que la mitad de las líneas en evaluación. El rendimiento de la línea FJB 08004 fue comparativamente alto y estable. Otros genotipos mostraron adaptación específica, por lo que su utilización debe considerarse en localidades específicas. El análisis AMMI permitió detectar localidades contrastantes en el estado de Guanajuato que deberán utilizarse en la evaluación de germoplasma mejorado para obtener información confiable asociada a un menor insumo de recursos.

  11. Granger Causality and Unit Roots

    DEFF Research Database (Denmark)

    Rodríguez-Caballero, Carlos Vladimir; Ventosa-Santaulària, Daniel

    2014-01-01

    The asymptotic behavior of the Granger-causality test under stochastic nonstationarity is studied. Our results confirm that the inference drawn from the test is not reliable when the series are integrated to the first order. In the presence of deterministic components, the test statistic diverges......, eventually rejecting the null hypothesis, even when the series are independent of each other. Moreover, controlling for these deterministic elements (in the auxiliary regressions of the test) does not preclude the possibility of drawing erroneous inferences. Granger-causality tests should not be used under...

  12. Quantum theory and local causality

    CERN Document Server

    Hofer-Szabó, Gábor

    2018-01-01

    This book summarizes the results of research the authors have pursued in the past years on the problem of implementing Bell's notion of local causality in local physical theories and relating it to other important concepts and principles in the foundations of physics such as the Common Cause Principle, Bell's inequalities, the EPR (Einstein-Podolsky-Rosen) scenario, and various other locality and causality concepts. The book is intended for philosophers of science with an interest in the formal background of sciences, philosophers of physics and physicists working in foundation of physics.

  13. [Causal analysis approaches in epidemiology].

    Science.gov (United States)

    Dumas, O; Siroux, V; Le Moual, N; Varraso, R

    2014-02-01

    Epidemiological research is mostly based on observational studies. Whether such studies can provide evidence of causation remains discussed. Several causal analysis methods have been developed in epidemiology. This paper aims at presenting an overview of these methods: graphical models, path analysis and its extensions, and models based on the counterfactual approach, with a special emphasis on marginal structural models. Graphical approaches have been developed to allow synthetic representations of supposed causal relationships in a given problem. They serve as qualitative support in the study of causal relationships. The sufficient-component cause model has been developed to deal with the issue of multicausality raised by the emergence of chronic multifactorial diseases. Directed acyclic graphs are mostly used as a visual tool to identify possible confounding sources in a study. Structural equations models, the main extension of path analysis, combine a system of equations and a path diagram, representing a set of possible causal relationships. They allow quantifying direct and indirect effects in a general model in which several relationships can be tested simultaneously. Dynamic path analysis further takes into account the role of time. The counterfactual approach defines causality by comparing the observed event and the counterfactual event (the event that would have been observed if, contrary to the fact, the subject had received a different exposure than the one he actually received). This theoretical approach has shown limits of traditional methods to address some causality questions. In particular, in longitudinal studies, when there is time-varying confounding, classical methods (regressions) may be biased. Marginal structural models have been developed to address this issue. In conclusion, "causal models", though they were developed partly independently, are based on equivalent logical foundations. A crucial step in the application of these models is the

  14. Flora ficologica da plataforma continental do litoral setentrional da bacia potiguar (RN), Brasil, com ênfase em chlorophyta

    OpenAIRE

    De Lourdes Montenegro Cocentino, Adilma

    2009-01-01

    Foram estudadas as macroalgas marinhas bentônicas de um habitat pouco explorado (Bacia Potiguar, Rio Grande do Norte, Nordeste do Brasil) e cuja informação florística é rara, para se conhecer a diversidade taxonômica e padrões de distribuição em um infralitoral tropical, onde vários empreendimentos estão em fase de instalação, sendo enfatizadas as Chlorophyta, como indicadoras da qualidade ambiental. Amostragens de macroalgas bentônicas foram feitas, com dois tipos de dragas e ...

  15. Coincidence of flowering time and the productivity and quality of cauliflower hybrid seeds Coincidência de florescimento entre linhagens de couve-flor na produtividade e qualidade de sementes híbridas

    Directory of Open Access Journals (Sweden)

    Marcelo Fontanetti Verdial

    2001-09-01

    Full Text Available The missing of flowering synchronization between the self-incompatible lines in a crop field of cauliflower hybrid seeds besides making the seed production smaller can compromise the genetic purity of them. The coincidence of the flowering time between two cauliflower lines was examined to study its effect on the productivity and quality of hybrid seeds. The treatments consisted of six different sowing dates, every fifteen days, using a self-incompatible tropical line pollinated by a winter line which does not present self-incompatibility. The following characteristics were evaluated: leaf average area and number of flowers per plant, number of siliques per plant, number and weight of seeds per plant, weight of thousand seeds and average number of seeds per silique. The germination standard test and genetic seed purity were determined for each treatment. The coincident flowering season between cauliflower lines affects directly the productivity and the genetic quality of the produced hybrid seeds. The closer the flowering time coincidence between the lines, the greater the number of seeds per silique and the smaller the percentage of non-hybrid seedlings. However, the coincidence of the flowering season between lines was found to influence physiological seed quality.A falta de sincronismo de florescimento entre as linhagens auto incompatíveis em um campo de produção de sementes híbridas de couve flor pode além de reduzir a produção de sementes comprometer a pureza genética das mesmas. Com o objetivo de estudar o efeito da coincidência de florescimento entre linhagens de couve-flor na produtividade e qualidade de sementes híbridas, foi realizado o presente experimento. Os tratamentos consistiram em seis diferentes épocas de semeadura, espaçadas a cada quinze dias, de uma linhagem de verão auto-incompatível que foi polinizada por uma linhagem de inverno que não apresenta auto-incompatibilidade. Observou-se a coincidência do

  16. Causal Reasoning with Mental Models

    Science.gov (United States)

    2014-08-08

    The initial rubric is equivalent to an exclusive disjunction between the two causal assertions. It 488 yields the following two mental models: 489...are 575 important, whereas the functions of artifacts are important (Ahn, 1998). A genetic code is 576 accordingly more critical to being a goat than

  17. Identity, causality, and pronoun ambiguity.

    Science.gov (United States)

    Sagi, Eyal; Rips, Lance J

    2014-10-01

    This article looks at the way people determine the antecedent of a pronoun in sentence pairs, such as: Albert invited Ron to dinner. He spent hours cleaning the house. The experiment reported here is motivated by the idea that such judgments depend on reasoning about identity (e.g., the identity of the he who cleaned the house). Because the identity of an individual over time depends on the causal-historical path connecting the stages of the individual, the correct antecedent will also depend on causal connections. The experiment varied how likely it is that the event of the first sentence (e.g., the invitation) would cause the event of the second (the house cleaning) for each of the two individuals (the likelihood that if Albert invited Ron to dinner, this would cause Albert to clean the house, versus cause Ron to clean the house). Decisions about the antecedent followed causal likelihood. A mathematical model of causal identity accounted for most of the key aspects of the data from the individual sentence pairs. Copyright © 2014 Cognitive Science Society, Inc.

  18. Charged singularities: the causality violation

    Energy Technology Data Exchange (ETDEWEB)

    De Felice, F; Nobili, L [Padua Univ. (Italy). Ist. di Fisica; Calvani, M [Padua Univ. (Italy). Ist. di Astronomia

    1980-12-01

    A search is made for examples of particle trajectories which, approaching a naked singularity from infinity, make up for lost time before going back to infinity. In the Kerr-Newman metric a whole family of such trajectories is found showing that the causality violation is indeed a non-avoidable pathology.

  19. Entanglement, holography and causal diamonds

    Science.gov (United States)

    de Boer, Jan; Haehl, Felix M.; Heller, Michal P.; Myers, Robert C.

    2016-08-01

    We argue that the degrees of freedom in a d-dimensional CFT can be reorganized in an insightful way by studying observables on the moduli space of causal diamonds (or equivalently, the space of pairs of timelike separated points). This 2 d-dimensional space naturally captures some of the fundamental nonlocality and causal structure inherent in the entanglement of CFT states. For any primary CFT operator, we construct an observable on this space, which is defined by smearing the associated one-point function over causal diamonds. Known examples of such quantities are the entanglement entropy of vacuum excitations and its higher spin generalizations. We show that in holographic CFTs, these observables are given by suitably defined integrals of dual bulk fields over the corresponding Ryu-Takayanagi minimal surfaces. Furthermore, we explain connections to the operator product expansion and the first law of entanglemententropy from this unifying point of view. We demonstrate that for small perturbations of the vacuum, our observables obey linear two-derivative equations of motion on the space of causal diamonds. In two dimensions, the latter is given by a product of two copies of a two-dimensional de Sitter space. For a class of universal states, we show that the entanglement entropy and its spin-three generalization obey nonlinear equations of motion with local interactions on this moduli space, which can be identified with Liouville and Toda equations, respectively. This suggests the possibility of extending the definition of our new observables beyond the linear level more generally and in such a way that they give rise to new dynamically interacting theories on the moduli space of causal diamonds. Various challenges one has to face in order to implement this idea are discussed.

  20. Entanglement, holography and causal diamonds

    Energy Technology Data Exchange (ETDEWEB)

    Boer, Jan de [Institute of Physics, Universiteit van Amsterdam,Science Park 904, 1090 GL Amsterdam (Netherlands); Haehl, Felix M. [Centre for Particle Theory & Department of Mathematical Sciences, Durham University,South Road, Durham DH1 3LE (United Kingdom); Heller, Michal P.; Myers, Robert C. [Perimeter Institute for Theoretical Physics,31 Caroline Street North, Waterloo, Ontario N2L 2Y5 (Canada)

    2016-08-29

    We argue that the degrees of freedom in a d-dimensional CFT can be re-organized in an insightful way by studying observables on the moduli space of causal diamonds (or equivalently, the space of pairs of timelike separated points). This 2d-dimensional space naturally captures some of the fundamental nonlocality and causal structure inherent in the entanglement of CFT states. For any primary CFT operator, we construct an observable on this space, which is defined by smearing the associated one-point function over causal diamonds. Known examples of such quantities are the entanglement entropy of vacuum excitations and its higher spin generalizations. We show that in holographic CFTs, these observables are given by suitably defined integrals of dual bulk fields over the corresponding Ryu-Takayanagi minimal surfaces. Furthermore, we explain connections to the operator product expansion and the first law of entanglement entropy from this unifying point of view. We demonstrate that for small perturbations of the vacuum, our observables obey linear two-derivative equations of motion on the space of causal diamonds. In two dimensions, the latter is given by a product of two copies of a two-dimensional de Sitter space. For a class of universal states, we show that the entanglement entropy and its spin-three generalization obey nonlinear equations of motion with local interactions on this moduli space, which can be identified with Liouville and Toda equations, respectively. This suggests the possibility of extending the definition of our new observables beyond the linear level more generally and in such a way that they give rise to new dynamically interacting theories on the moduli space of causal diamonds. Various challenges one has to face in order to implement this idea are discussed.

  1. The argumentative impact of causal relations

    DEFF Research Database (Denmark)

    Nielsen, Anne Ellerup

    1996-01-01

    such as causality, explanation and justification. In certain types of discourse, causal relations also imply an intentional element. This paper describes the way in which the semantic and pragmatic functions of causal markers can be accounted for in terms of linguistic and rhetorical theories of argumentation.......The semantic relations between and within utterances are marked by the use of connectors and adverbials. One type of semantic relations is causal relations expressed by causal markers such as because, therefore, so, for, etc. Some of these markers cover different types of causal relations...

  2. Estudo florístico do componente herbáceo e relação com solos em áreas de caatinga do embasamento cristalino e bacia sedimentar, Petrolândia, PE, Brasil Herbaceous floristic study and relationship with soil of crystalline shield and sedimentary basin caatinga areas at Petrolândia, Pernambuco State, Brazil

    Directory of Open Access Journals (Sweden)

    Kleber Andrade da Silva

    2009-03-01

    Full Text Available Realizou-se um levantamento florístico em áreas de caatinga do embasamento cristalino e de bacia sedimentar, em Petrolândia, Pernambuco, objetivando-se identificar diferenças na composição, hábito e forma de vida das herbáceas entre as duas áreas. Foram coletadas amostras de solo nas profundidades de 0 a 20 cm e de 20 a 40 cm. Foram estabelecidas 100 parcelas de 1×1 m em cada área e coletadas todas as espécies herbáceas. De modo geral, o solo da área do embasamento cristalino foi mais fértil, raso, com maior capacidade de reter água e maior porcentagem de argila. Os números de famílias, gêneros e espécies das áreas da bacia sedimentar e do embasamento cristalino foram 32, 62 e 78 e 31, 53 e 69, respectivamente. A similaridade florística entre as áreas foi alta (75%. A análise de agrupamento mostrou que os arranjos florísticos entre as parcelas amostradas são mais semelhantes dentro de cada área que entre áreas, sugerindo a existência de grupos distintos. Tipo de solo parece não ser um fator decisivo na similaridade florística, hábito e proporção de forma de vida das herbáceas da vegetação da caatinga quando as áreas são próximas, mas pode influenciar a ocorrência e a freqüência de algumas espécies.Floristic surveys were carried out in two close caatinga areas, one on the crystalline shield and the other on a sedimentary basin, both at Petrolândia, Pernambuco, Brazil, with the objective of identifying differences between the two areas in composition, habit and life form of the herbaceous flora. One hundred 1×1 m plots were established in each area and all the herbaceous species were identified. Soil samples were collected at 0-20 and 20-40 cm depths. In general, the soil in the crystalline shield area was shallower, had greater clay content, with higher water holding capacity, and was more fertile. The number of families, genera and species in the sedimentary basin and crystalline shield areas were 32

  3. Comparação florística e estrutural de duas florestas de várzea no estuário amazônico, Pará, Brasil

    Directory of Open Access Journals (Sweden)

    Fábio de Jesus Batista

    2011-04-01

    Full Text Available O objetivo deste trabalho foi conhecer e comparar a composição florística e a estrutura de duas áreas de florestas de várzea localizadas na reserva extrativista Chocoaré-Mato Grosso, Santarém Novo-PA. O inventário florístico abrangeu 1,5 ha em parcelas de 10 x 100 m, distribuídas na área 1 (1,0 ha e área 2 (0,5 ha. Foram identificados os indivíduos arbóreos com circunferência a 1,3 m altura do solo (CAP > 30 cm e demonstrada a riqueza, área basal e o IVI (Índice de Valor de Importância para cada área. A relação entre as áreas foi realizada por meio da similaridade de espécies, densidade, área basal, análise de agrupamento e espécies indicadoras. Na área 1, ocorreram 613 ind.ha-1 (26,67 m².ha-1 distribuídos em 17 famílias, 33 gêneros e 34 espécies com Euterpe oleracea, Enterolobium maximum, Symphonia globulifera, Pterocarpus amazonicus e Virola surinamensis apresentando os maiores IVI's e a área 2 com 744 ind.ha-1 (35,34 m².ha-1 em 13 famílias, 24 gêneros e 26 espécies com Mauritia flexuosa, Euterpe oleracea, Virola surinamensis, Tapirira guianensis e Inga thibaudiana com os maiores IVI's. As áreas registraram baixas similaridades entre si (0,18 e tanto a densidade quanto a área basal foram superiores na área 2. O agrupamento separou as áreas entre si e das 51 espécies, apenas 15 foram indicadoras. Conclui-se que, as florestas apresentaram baixa riqueza com pouca semelhança entre as populações arbóreas e as espécies indicadoras ocorreram nas áreas 1 e 2.

  4. La flor de mi secreto (Almodóvar, 1995: La literatura como seducción

    Directory of Open Access Journals (Sweden)

    Martínez-Carazo, Cristina

    2011-04-01

    Full Text Available The multiple references to writing in Pedro Almodovar’s La flor de mi secreto (1995 have arguably made this film his most literary. Reading and writing function as the structural axis of the movie because they define the existence of the main character - Leo/Amanda Gris. But beyond the constant literary allusions, what makes the “literarity” of this film is, on the one hand, the construction of the protagonist according to literary models and on the other the exploration of her subjectivity through her writing. Leo as a character is created as a replica of the tormented writers that she admires. In their stereotypical tradition, she is an alcoholic, addicted to sleeping pills, suicidal, obsessed with her loneliness and installed in her writing as a survival space. Furthermore, the spectator accesses her subjectivity through her career as a writer because her melodramatic life gets entangled with her novels. Almodóvar projects his literary ghosts in La flor de mi secreto and in the process, subverts the parameters of literature, the canon, the gender and genre categories and the question of authorship. He also resists a stable definition of literature as art by inserting it in a filmic text, favoring a complex intertextuality which contributes to dissolving the frontiers between high and low culture and to opening a common ground for the arts.Las múltiples referencias a la escritura presentes en La flor de mi secreto (1995 han llevado a etiquetar esta película como la más literaria de Pedro Almodóvar. La lectura y la escritura funcionan como hilo conductor de la película en la medida en que articulan la existencia de la protagonista, Leo/Amanda Gris. Pero más allá de este despliegue de alusiones literarias, lo que en realidad determina la literaridad del film es, por un lado, la construcción de dicho personaje a partir de modelos literarios y por otro la exploración de su subjetividad a partir de la escritura. Leo se perfila como

  5. Spectral dimension in causal set quantum gravity

    International Nuclear Information System (INIS)

    Eichhorn, Astrid; Mizera, Sebastian

    2014-01-01

    We evaluate the spectral dimension in causal set quantum gravity by simulating random walks on causal sets. In contrast to other approaches to quantum gravity, we find an increasing spectral dimension at small scales. This observation can be connected to the nonlocality of causal set theory that is deeply rooted in its fundamentally Lorentzian nature. Based on its large-scale behaviour, we conjecture that the spectral dimension can serve as a tool to distinguish causal sets that approximate manifolds from those that do not. As a new tool to probe quantum spacetime in different quantum gravity approaches, we introduce a novel dimensional estimator, the causal spectral dimension, based on the meeting probability of two random walkers, which respect the causal structure of the quantum spacetime. We discuss a causal-set example, where the spectral dimension and the causal spectral dimension differ, due to the existence of a preferred foliation. (paper)

  6. On causal nonrelativistic classical electrodynamics

    International Nuclear Information System (INIS)

    Goedecke, G.H.

    1984-01-01

    The differential-difference (DD) motion equations of the causal nonrelativistic classical electrodynamics developed by the author in 1975 are shown to possess only nonrunaway, causal solutions with no discontinuities in particle velocity or position. As an example, the DD equation solution for the problem of an electromagnetic shock incident on an initially stationary charged particle is contrasted with the standard Abraham-Lorentz equation solution. The general Cauchy problem for these DD motion equations is discussed. In general, in order to uniquely determine a solution, the initial data must be more detailed than the standard Cauchy data of initial position and velocity. Conditions are given under which the standard Cauchy data will determine the DD equation solutions to sufficient practical accuracy

  7. Quantum mechanics, relativity and causality

    International Nuclear Information System (INIS)

    Tati, Takao.

    1975-07-01

    In quantum mechanics, the state is prepared by a measurement on a space-like surface sigma. What is that determines the surface sigma on which the measurement prepares the state It is considered either a mechanism proper to the measuring process (apparatus) or a universal property of space-time. In the former case, problems arise, concerning causality or conservation of probability due to that the velocity of reduction of wave-packet is considered to exceed the light velocity. The theory of finite degree of freedom proposed previously belongs to the latter case. In this theory, the surface sigma is restricted to the hyper-plane perpendicular to a universal time-like vector governing causal relations. We propose an experiment to discriminate between the above-mentioned two cases and to test the existence of the universal time-like vector. (auth.)

  8. CRESCIMENTO RADICULAR DE MUDAS DE COUVE-FLOR PRODUZIDAS EM DIFERENTES SUBSTRATOS DE PRODUÇÃO AGROECOLOGICA

    Directory of Open Access Journals (Sweden)

    Julio Cesar Gradice Saluci

    2017-05-01

    Full Text Available Este trabalho teve como objetivo avaliar o desempenho de mudas de couve flor, semeadas em diferentes substratos: e concentrações  orgânicas formuladas a partir de matéria prima disponível na região. O estudo foi desenhado no delineamento inteiramente casualizado com sete repetições considerando uma planta por repetição, em esquema fatorial 4x4, quatro substratos e quatro concentrações os tratamentos foram quatro tipos de substratos sendo um comercial comumente utilizado para produção de mudas de hortaliças e três orgânicos de produção agroecológica, ambos produzidos no setor de agroecologia do ifes-campus de alegre, sendo: S1- Composto orgânico produzido pelo processo de compostagem de restos de poda de jardim e esterco bovina fresco, de acordo com a metodologia de (SOUZA et al., 2013; S2- Vermicomposto produzido com o composto orgânico no qual foi inserido minhocas Eisenia foetida para realizar o processo de vermicompostagem e S3 - Composto orgânico  com cinzas de madeira + restos de poda de jardins + esterco bovino, compostado em sistemas de pilhas. As concentrações foram 25, 50, 75 e 100% de substrato completados com volumoso de terra de barranco característica de horizonte c, completados em volumes. Os substratos  orgânicos apresentaram bons desenvolvimento de raiz para as mudas de couve flor.

  9. Causal Set Generator and Action Computer

    OpenAIRE

    Cunningham, William; Krioukov, Dmitri

    2017-01-01

    The causal set approach to quantum gravity has gained traction over the past three decades, but numerical experiments involving causal sets have been limited to relatively small scales. The software suite presented here provides a new framework for the generation and study of causal sets. Its efficiency surpasses previous implementations by several orders of magnitude. We highlight several important features of the code, including the compact data structures, the $O(N^2)$ causal set generatio...

  10. Modeling of causality with metamaterials

    International Nuclear Information System (INIS)

    Smolyaninov, Igor I

    2013-01-01

    Hyperbolic metamaterials may be used to model a 2 + 1-dimensional Minkowski space–time in which the role of time is played by one of the spatial coordinates. When a metamaterial is built and illuminated with a coherent extraordinary laser beam, the stationary pattern of light propagation inside the metamaterial may be treated as a collection of particle world lines, which represents a complete ‘history’ of this 2 + 1-dimensional space–time. While this model may be used to build interesting space–time analogs, such as metamaterial ‘black holes’ and a metamaterial ‘big bang’, it lacks causality: since light inside the metamaterial may propagate back and forth along the ‘timelike’ spatial coordinate, events in the ‘future’ may affect events in the ‘past’. Here we demonstrate that a more sophisticated metamaterial model may fix this deficiency via breaking the mirror and temporal (PT) symmetries of the original model and producing one-way propagation along the ‘timelike’ spatial coordinate. The resulting 2 + 1-dimensional Minkowski space–time appears to be causal. This scenario may be considered as a metamaterial model of the Wheeler–Feynman absorber theory of causality. (paper)

  11. THE CAUSAL ANALYSIS / DIAGNOSIS DECISION ...

    Science.gov (United States)

    CADDIS is an on-line decision support system that helps investigators in the regions, states and tribes find, access, organize, use and share information to produce causal evaluations in aquatic systems. It is based on the US EPA's Stressor Identification process which is a formal method for identifying causes of impairments in aquatic systems. CADDIS 2007 increases access to relevant information useful for causal analysis and provides methods and tools that practitioners can use to analyze their own data. The new Candidate Cause section provides overviews of commonly encountered causes of impairments to aquatic systems: metals, sediments, nutrients, flow alteration, temperature, ionic strength, and low dissolved oxygen. CADDIS includes new Conceptual Models that illustrate the relationships from sources to stressors to biological effects. An Interactive Conceptual Model for phosphorus links the diagram with supporting literature citations. The new Analyzing Data section helps practitioners analyze their data sets and interpret and use those results as evidence within the USEPA causal assessment process. Downloadable tools include a graphical user interface statistical package (CADStat), and programs for use with the freeware R statistical package, and a Microsoft Excel template. These tools can be used to quantify associations between causes and biological impairments using innovative methods such as species-sensitivity distributions, biological inferenc

  12. Causal structure of analogue spacetimes

    International Nuclear Information System (INIS)

    Barcelo, Carlos; Liberati, Stefano; Sonego, Sebastiano; Visser, Matt

    2004-01-01

    The so-called 'analogue models of general relativity' provide a number of specific physical systems, well outside the traditional realm of general relativity, that nevertheless are well-described by the differential geometry of curved spacetime. Specifically, the propagation of perturbations in these condensed matter systems is described by 'effective metrics' that carry with them notions of 'causal structure' as determined by an exchange of quasi-particles. These quasi-particle-induced causal structures serve as specific examples of what can be done in the presence of a Lorentzian metric without having recourse to the Einstein equations of general relativity. (After all, the underlying analogue model is governed by its own specific physics, not necessarily by the Einstein equations.) In this paper we take a careful look at what can be said about the causal structure of analogue spacetimes, focusing on those containing quasi-particle horizons, both with a view to seeing what is different from standard general relativity, and what the similarities might be. For definiteness, and because the physics is particularly simple to understand, we will phrase much of the discussion in terms of acoustic disturbances in moving fluids, where the underlying physics is ordinary fluid mechanics, governed by the equations of traditional hydrodynamics, and the relevant quasi-particles are the phonons. It must however be emphasized that this choice of example is only for the sake of pedagogical simplicity and that our considerations apply generically to wide classes of analogue spacetimes

  13. Obesity and infection: reciprocal causality.

    Science.gov (United States)

    Hainer, V; Zamrazilová, H; Kunešová, M; Bendlová, B; Aldhoon-Hainerová, I

    2015-01-01

    Associations between different infectious agents and obesity have been reported in humans for over thirty years. In many cases, as in nosocomial infections, this relationship reflects the greater susceptibility of obese individuals to infection due to impaired immunity. In such cases, the infection is not related to obesity as a causal factor but represents a complication of obesity. In contrast, several infections have been suggested as potential causal factors in human obesity. However, evidence of a causal linkage to human obesity has only been provided for adenovirus 36 (Adv36). This virus activates lipogenic and proinflammatory pathways in adipose tissue, improves insulin sensitivity, lipid profile and hepatic steatosis. The E4orf1 gene of Adv36 exerts insulin senzitizing effects, but is devoid of its pro-inflammatory modalities. The development of a vaccine to prevent Adv36-induced obesity or the use of E4orf1 as a ligand for novel antidiabetic drugs could open new horizons in the prophylaxis and treatment of obesity and diabetes. More experimental and clinical studies are needed to elucidate the mutual relations between infection and obesity, identify additional infectious agents causing human obesity, as well as define the conditions that predispose obese individuals to specific infections.

  14. Behavioural Pattern of Causality Parameter of Autoregressive ...

    African Journals Online (AJOL)

    In this paper, a causal form of Autoregressive Moving Average process, ARMA (p, q) of various orders and behaviour of the causality parameter of ARMA model is investigated. It is deduced that the behaviour of causality parameter ψi depends on positive and negative values of autoregressive parameter φ and moving ...

  15. Exploring Individual Differences in Preschoolers' Causal Stance

    Science.gov (United States)

    Alvarez, Aubry; Booth, Amy E.

    2016-01-01

    Preschoolers, as a group, are highly attuned to causality, and this attunement is known to facilitate memory, learning, and problem solving. However, recent work reveals substantial individual variability in the strength of children's "causal stance," as demonstrated by their curiosity about and preference for new causal information. In…

  16. Representing Personal Determinants in Causal Structures.

    Science.gov (United States)

    Bandura, Albert

    1984-01-01

    Responds to Staddon's critique of the author's earlier article and addresses issues raised by Staddon's (1984) alternative models of causality. The author argues that it is not the formalizability of causal processes that is the issue but whether cognitive determinants of behavior are reducible to past stimulus inputs in causal structures.…

  17. Causal inference in economics and marketing.

    Science.gov (United States)

    Varian, Hal R

    2016-07-05

    This is an elementary introduction to causal inference in economics written for readers familiar with machine learning methods. The critical step in any causal analysis is estimating the counterfactual-a prediction of what would have happened in the absence of the treatment. The powerful techniques used in machine learning may be useful for developing better estimates of the counterfactual, potentially improving causal inference.

  18. Causal knowledge and reasoning in decision making

    NARCIS (Netherlands)

    Hagmayer, Y.; Witteman, C.L.M.

    2017-01-01

    Normative causal decision theories argue that people should use their causal knowledge in decision making. Based on these ideas, we argue that causal knowledge and reasoning may support and thereby potentially improve decision making based on expected outcomes, narratives, and even cues. We will

  19. A theory of causal learning in children: causal maps and Bayes nets.

    Science.gov (United States)

    Gopnik, Alison; Glymour, Clark; Sobel, David M; Schulz, Laura E; Kushnir, Tamar; Danks, David

    2004-01-01

    The authors outline a cognitive and computational account of causal learning in children. They propose that children use specialized cognitive systems that allow them to recover an accurate "causal map" of the world: an abstract, coherent, learned representation of the causal relations among events. This kind of knowledge can be perspicuously understood in terms of the formalism of directed graphical causal models, or Bayes nets. Children's causal learning and inference may involve computations similar to those for learning causal Bayes nets and for predicting with them. Experimental results suggest that 2- to 4-year-old children construct new causal maps and that their learning is consistent with the Bayes net formalism.

  20. Norms and customs: causally important or causally impotent?

    Science.gov (United States)

    Jones, Todd

    2010-01-01

    In this article, I argue that norms and customs, despite frequently being described as being causes of behavior in the social sciences and ordinary conversation, cannot really cause behavior. Terms like "norms" and the like seem to refer to philosophically disreputable disjunctive properties. More problematically, even if they do not, or even if there can be disjunctive properties after all, I argue that norms and customs still cannot cause behavior. The social sciences would be better off without referring to properties like norms and customs as if they could be causal.

  1. A theory of causal learning in children: Causal maps and Bayes nets

    OpenAIRE

    Gopnik, A; Glymour, C; Sobel, D M; Schulz, L E; Kushnir, T; Danks, D

    2004-01-01

    The authors outline a cognitive and computational account of causal learning in children. They propose that children use specialized cognitive systems that allow them to recover an accurate "causal map" of the world: an abstract, coherent, learned representation of the causal relations among events. This kind of knowledge can be perspicuously understood in terms of the formalism of directed graphical causal models, or Bayes nets. Children's causal learning and inference may involve computatio...

  2. Causal mediation analysis with multiple causally non-ordered mediators.

    Science.gov (United States)

    Taguri, Masataka; Featherstone, John; Cheng, Jing

    2018-01-01

    In many health studies, researchers are interested in estimating the treatment effects on the outcome around and through an intermediate variable. Such causal mediation analyses aim to understand the mechanisms that explain the treatment effect. Although multiple mediators are often involved in real studies, most of the literature considered mediation analyses with one mediator at a time. In this article, we consider mediation analyses when there are causally non-ordered multiple mediators. Even if the mediators do not affect each other, the sum of two indirect effects through the two mediators considered separately may diverge from the joint natural indirect effect when there are additive interactions between the effects of the two mediators on the outcome. Therefore, we derive an equation for the joint natural indirect effect based on the individual mediation effects and their interactive effect, which helps us understand how the mediation effect works through the two mediators and relative contributions of the mediators and their interaction. We also discuss an extension for three mediators. The proposed method is illustrated using data from a randomized trial on the prevention of dental caries.

  3. Composição florística e variações morfo-pedológicas em uma área de Caatinga em Pernambuco

    OpenAIRE

    Romênia Pinheiro Nascimento, Katarina

    2010-01-01

    Dois diferentes ambientes vegetacionais são reconhecidos para a caatinga, estando estes relacionados as unidades geológicas: matriz cristalina e as bacias e chapadas sedimentares. Contudo, não se sabe se as plantas como um todo respondem a esta repartição florística, além de, até que ponto existe a influência de fatores ambientais sobre a vegetação. Assim, este trabalho tem por objetivo analisar a composição florística através de uma análise comparativa entre doze áreas de caat...

  4. Florística de lianas em um fragmento de floresta estacional semidecidual, Parque Estadual de Vassununga, Santa Rita do Passa Quatro, SP, Brasil Floristic of lianas in a fragment of seasonal semidecidual forest State Park of Vassununga, Santa Rita do Passa Quatro, São Paulo State, Brazil

    Directory of Open Access Journals (Sweden)

    Yara Junqueira de Azevedo Tibiriçá

    2006-06-01

    Full Text Available Embora o conhecimento sobre a florística dos fragmentos de florestas estacionais semideciduais tenha crescido nos últimos anos, ainda sabe-se pouco sobre a comunidade de lianas (lenhosas ou herbáceas nesses fragmentos. Assim, foi realizado o levantamento florístico de lianas na gleba Maravilha, pertencente ao Parque Estadual de Vassununga (Santa Rita do Passa Quatro, SP, a fim de colaborar com o conhecimento dessa comunidade e subsidiar futuros trabalhos que envolvam essa forma de vida. A área de estudo compreende 127,08 ha, com inverno seco e temperatura média anual de 22 ºC. Para a coleta do material, percorreu-se mensalmente toda a borda do fragmento e três trilhas no interior da mata, de agosto/2002 a setembro/2003. Foram identificadas 120 espécies de lianas, pertencentes a 30 famílias e 71 gêneros, das quais 51% das espécies são volúveis, 42% apresentam gavinhas e apenas 7% são escandentes. As famílias mais representativas em número de espécies foram: Bignoniaceae (26, Malpighiaceae (14, Sapindaceae (12 e Asteraceae (9. Houve baixa similaridade florística entre as espécies de lianas presentes na gleba Maravilha em relação a outras áreas de florestas estacionais semideciduais do interior paulista.Although the knowledge about the floristic composition of the fragments of seasonal semidecidual forest had grown in the last few years, little is known about the liana communities (woody vines and herbaceous vines in those fragments. To collaborate with the knowledgement of the lianas and subsidize future works involving this life form, a floristic survey of the liana species occurring at the fragment Maravilha of the State Park of Vassununga (Santa Rita do Passa Quatro - SP was carried out. The study area comprised 127.08ha, with average temperature of 22 ºC. The whole border of the forest fragment and three tracks inside the forest were surveyed monthly between August 2002 and September 2003. One hundred and twenty species

  5. Heterogeneidade florística das fitocenoses de restingas nos estados do Rio de Janeiro e Espírito Santo, Brasil

    Directory of Open Access Journals (Sweden)

    Luiz Fernando Silva Magnago

    2011-04-01

    Full Text Available Esta pesquisa teve como objetivo comparar florísticamente as formações vegetacionais que compõe o ecossistema Restinga dos Estados do Rio de Janeiro e Espírito Santo. Para isto foi realizado uma compilação de dados de levantamentos florísticos e fitossociológicos, sendo utilizado para esta análise o índice de similaridade de Jaccard, onde as interpretações se deram pela média de grupo (UPGMA. As 11 formações analisadas apresentaram uma riqueza total de 990 espécies, distribuídas em 141 famílias, sendo Fabaceae (73, Myrtaceae (59, Rubiaceae (48, Orchidaceae (44, Cyperaceae (38, Poaceae (36, Bromeliaceae (35, Euphorbiaceae (30, Asteraceae (30 as de maior riqueza. A similaridade entre as formações foi baixa, sendo o maior valor de 33%. Os resultados obtidos denotam uma alta heterogeneidade florística existente nas formações que compõe o ecossistema Restinga nos dois Estados analisados, sendo esta determinada por diferentes fatores que atuam em cada fitocenose.

  6. The Functions of Danish Causal Conjunctions

    Directory of Open Access Journals (Sweden)

    Rita Therkelsen

    2004-01-01

    Full Text Available In the article I propose an analysis of the Danish causal conjunctions fordi, siden and for based on the framework of Danish Functional Grammar. As conjunctions they relate two clauses, and their semantics have in common that it indicates a causal relationship between the clauses. The causal conjunctions are different as far as their distribution is concerned; siden conjoins a subordinate clause and a main clause, for conjoins two main clauses, and fordi is able to do both. Methodologically I have based my analysis on these distributional properties comparing siden and fordi conjoining a subordinate and a main clause, and comparing for and fordi conjoining two main clauses, following the thesis that they would establish a causal relationship between different kinds of content. My main findings are that fordi establishes a causal relationship between the events referred to by the two clauses, and the whole utterance functions as a statement of this causal relationship. Siden presupposes such a general causal relationship between the two events and puts forward the causing event as a reason for assuming or wishing or ordering the caused event, siden thus establishes a causal relationship between an event and a speech act. For equally presupposes a general causal relationship between two events and it establishes a causal relationship between speech acts, and fordi conjoining two main clauses is able to do this too, but in this position it also maintains its event-relating ability, the interpretation depending on contextual factors.

  7. Space and time in perceptual causality

    Directory of Open Access Journals (Sweden)

    Benjamin Straube

    2010-04-01

    Full Text Available Inferring causality is a fundamental feature of human cognition that allows us to theorize about and predict future states of the world. Michotte suggested that humans automatically perceive causality based on certain perceptual features of events. However, individual differences in judgments of perceptual causality cast doubt on Michotte’s view. To gain insights in the neural basis of individual difference in the perception of causality, our participants judged causal relationships in animations of a blue ball colliding with a red ball (a launching event while fMRI-data were acquired. Spatial continuity and temporal contiguity were varied parametrically in these stimuli. We did not find consistent brain activation differences between trials judged as caused and those judged as non-caused, making it unlikely that humans have universal instantiation of perceptual causality in the brain. However, participants were slower to respond to and showed greater neural activity for violations of causality, suggesting that humans are biased to expect causal relationships when moving objects appear to interact. Our participants demonstrated considerable individual differences in their sensitivity to spatial and temporal characteristics in perceiving causality. These qualitative differences in sensitivity to time or space in perceiving causality were instantiated in individual differences in activation of the left basal ganglia or right parietal lobe, respectively. Thus, the perception that the movement of one object causes the movement of another is triggered by elemental spatial and temporal sensitivities, which themselves are instantiated in specific distinct neural networks.

  8. Causal diagrams in systems epidemiology

    Directory of Open Access Journals (Sweden)

    Joffe Michael

    2012-03-01

    Full Text Available Abstract Methods of diagrammatic modelling have been greatly developed in the past two decades. Outside the context of infectious diseases, systematic use of diagrams in epidemiology has been mainly confined to the analysis of a single link: that between a disease outcome and its proximal determinant(s. Transmitted causes ("causes of causes" tend not to be systematically analysed. The infectious disease epidemiology modelling tradition models the human population in its environment, typically with the exposure-health relationship and the determinants of exposure being considered at individual and group/ecological levels, respectively. Some properties of the resulting systems are quite general, and are seen in unrelated contexts such as biochemical pathways. Confining analysis to a single link misses the opportunity to discover such properties. The structure of a causal diagram is derived from knowledge about how the world works, as well as from statistical evidence. A single diagram can be used to characterise a whole research area, not just a single analysis - although this depends on the degree of consistency of the causal relationships between different populations - and can therefore be used to integrate multiple datasets. Additional advantages of system-wide models include: the use of instrumental variables - now emerging as an important technique in epidemiology in the context of mendelian randomisation, but under-used in the exploitation of "natural experiments"; the explicit use of change models, which have advantages with respect to inferring causation; and in the detection and elucidation of feedback.

  9. Causal diagrams in systems epidemiology.

    Science.gov (United States)

    Joffe, Michael; Gambhir, Manoj; Chadeau-Hyam, Marc; Vineis, Paolo

    2012-03-19

    Methods of diagrammatic modelling have been greatly developed in the past two decades. Outside the context of infectious diseases, systematic use of diagrams in epidemiology has been mainly confined to the analysis of a single link: that between a disease outcome and its proximal determinant(s). Transmitted causes ("causes of causes") tend not to be systematically analysed.The infectious disease epidemiology modelling tradition models the human population in its environment, typically with the exposure-health relationship and the determinants of exposure being considered at individual and group/ecological levels, respectively. Some properties of the resulting systems are quite general, and are seen in unrelated contexts such as biochemical pathways. Confining analysis to a single link misses the opportunity to discover such properties.The structure of a causal diagram is derived from knowledge about how the world works, as well as from statistical evidence. A single diagram can be used to characterise a whole research area, not just a single analysis - although this depends on the degree of consistency of the causal relationships between different populations - and can therefore be used to integrate multiple datasets.Additional advantages of system-wide models include: the use of instrumental variables - now emerging as an important technique in epidemiology in the context of mendelian randomisation, but under-used in the exploitation of "natural experiments"; the explicit use of change models, which have advantages with respect to inferring causation; and in the detection and elucidation of feedback.

  10. Probabilistic causality and radiogenic cancers

    International Nuclear Information System (INIS)

    Groeer, P.G.

    1986-01-01

    A review and scrutiny of the literature on probability and probabilistic causality shows that it is possible under certain assumptions to estimate the probability that a certain type of cancer diagnosed in an individual exposed to radiation prior to diagnosis was caused by this exposure. Diagnosis of this causal relationship like diagnosis of any disease - malignant or not - requires always some subjective judgments by the diagnostician. It is, therefore, illusory to believe that tables based on actuarial data can provide objective estimates of the chance that a cancer diagnosed in an individual is radiogenic. It is argued that such tables can only provide a base from which the diagnostician(s) deviate in one direction or the other according to his (their) individual (consensual) judgment. Acceptance of a physician's diagnostic judgment by patients is commonplace. Similar widespread acceptance of expert judgment by claimants in radiation compensation cases does presently not exist. Judicious use of the present radioepidemiological tables prepared by the Working Group of the National Institutes of Health or of updated future versions of similar tables may improve the situation. 20 references

  11. Composição florística e espectro biológico na Estação Ecológica de Santa Bárbara, estado de São Paulo, Brasil Floristic composition and biological spectra in Santa Barbara Ecological Station, Brazil

    Directory of Open Access Journals (Sweden)

    João Augusto Alves Meira Neto

    2007-10-01

    Full Text Available O conhecimento da flora herbáceo-subarbustiva, juntamente com o da flora lenhosa, auxilia a determinação dos padrões florísticos e permite descrever o espectro biológico com conseqüentes inferências sobre a atua��ão de fatores ambientais e históricos na vegetação. Considerando que poucos trabalhos se aprofundaram no estudo da flora herbáceo-subarbustiva de Cerrado, embora esta seja mais rica que a lenhosa, objetivou-se estudar a composição e os padrões florísticos das floras herbáceo-subarbustiva e lenhosa da Estação Ecológica de Santa Bárbara (EESB (22º 46' 30'' a 22º 50' 30''S e 49º 10' 30'' a 49º15'30'' W , 600 a 680 m de altitude, Município de Águas de Santa Bárbara, Estado de São Paulo. Visou-se, ainda, determinar o espectro biológico para efetuar análises comparativas das diferentes fitofisionomias de Cerrado dessa Unidade de Conservação. Foram encontradas 314 espécies na EESB, sendo 285 em Cerrado sensu lato. As famílias mais ricas em número de espécies foram Asteraceae, Leguminosae, Myrtaceae e Poaceae. Há uma constante ocorrência de Asteraceae, Leguminosae e Poaceae entre as famílias mais ricas, concordando com o observado nos estudos florísticos de Cerrado que incluíram os estratos lenhoso e herbáceo-subarbustivo. O espectro biológico corroborou os padrões anteriormente descritos para o Cerrado sensu lato, exceto pela maior expressão de caméfitas em relação às hemicriptófitas nas fisionomias campestres da EESB, o que pode ser efeito da proteção ao fogo nessa Unidade de Conservação.Only few surveys were carried out on woody and ground layer floras of the Brazilian Cerrado. The objective of this survey was to investigate richness, floristic patterns and biological spectra of different phytophysiognomies on both strata at Santa Bárbara Ecological Station (EESB. EESB is located in the Municipality of Águas de Santa Bárbara, São Paulo State, Brazil (22º 46' 30'' to 22º 50' 30

  12. Composição florística de plantas daninhas em um lago do Rio Solimões, Amazonas Floristic composition of weeds in a lake of Solimoes River, Amazonas, Brazil

    Directory of Open Access Journals (Sweden)

    S.M.F. Albertino

    2009-03-01

    Full Text Available As áreas inundáveis localizadas na bacia dos rios Amazonas e Solimões são denominadas várzeas. A inundação é um evento natural que promove mudanças na estrutura e composição florística dessas comunidades. O conhecimento da diversidade de espécies é de fundamental importância para o entendimento da dinâmica da regeneração natural de espécies nos ecossistemas amazônicos. Este trabalho teve como objetivo levantar a composição florística do solo do fundo do lago do Manaquiri-AM, em um período de seca excepcional, ocorrida em 2005, na Amazônia. Foram realizadas coletas de material botânico em duas áreas do lago, em novembro de 2005; para a amostragem, utilizou-se um quadrado de madeira de 0,36 m², atirado aleatoriamente por 20 vezes em cada local de estudo. A vegetação emergente foi de 5.958 indivíduos, distribuídos em sete famílias e nove espécies. As famílias mais representativas em número de espécies foram Poaceae e Cyperaceae. Cyperus esculentus e Luziola spruceana foram as mais frequentes, e Mimosa pudica e Alternanthera sessilis, as de maior abundância. C. esculentus e M. pudica apresentaram maior número de indivíduos, de densidade e de valor de importância. As espécies de plantas encontradas neste estudo mantiveram sua capacidade de crescer e se desenvolver mesmo após longo período submersas.The swamps located at the basins of the Amazonas and Solimões rivers are denominated "várzeas". In these areas, flooding is a natural event that changes the structure and composition of the local plants. Thus, knowing the species diversity in these Amazon region areas is extremely important to understand the dynamics of the natural regeneration of the Amazon ecosystem species. Accordingly, the goal of this study was to survey the soil floristic composition at the bottom of the Manaquiri Lake, Amazon, during an exceptional dry period in 2005. Plants were collected in two areas of the lake in November 2005. Flora

  13. Linear causal modeling with structural equations

    CERN Document Server

    Mulaik, Stanley A

    2009-01-01

    Emphasizing causation as a functional relationship between variables that describe objects, Linear Causal Modeling with Structural Equations integrates a general philosophical theory of causation with structural equation modeling (SEM) that concerns the special case of linear causal relations. In addition to describing how the functional relation concept may be generalized to treat probabilistic causation, the book reviews historical treatments of causation and explores recent developments in experimental psychology on studies of the perception of causation. It looks at how to perceive causal

  14. Causal relationship: a new tool for the causal characterization of Lorentzian manifolds

    International Nuclear Information System (INIS)

    Garcia-Parrado, Alfonso; Senovilla, Jose M M

    2003-01-01

    We define and study a new kind of relation between two diffeomorphic Lorentzian manifolds called a causal relation, which is any diffeomorphism characterized by mapping every causal vector of the first manifold onto a causal vector of the second. We perform a thorough study of the mathematical properties of causal relations and prove in particular that two given Lorentzian manifolds (say V and W) may be causally related only in one direction (say from V to W, but not from W to V). This leads us to the concept of causally equivalent (or isocausal in short) Lorentzian manifolds as those mutually causally related and to a definition of causal structure over a differentiable manifold as the equivalence class formed by isocausal Lorentzian metrics upon it. Isocausality is a more general concept than the conformal relationship, because we prove the remarkable result that a conformal relation φ is characterized by the fact of being a causal relation of the particular kind in which both φ and φ -1 are causal relations. Isocausal Lorentzian manifolds are mutually causally compatible, they share some important causal properties, and there are one-to-one correspondences, which are sometimes non-trivial, between several classes of their respective future (and past) objects. A more important feature is that they satisfy the same standard causality constraints. We also introduce a partial order for the equivalence classes of isocausal Lorentzian manifolds providing a classification of all the causal structures that a given fixed manifold can have. By introducing the concept of causal extension we put forward a new definition of causal boundary for Lorentzian manifolds based on the concept of isocausality, and thereby we generalize the traditional Penrose constructions of conformal infinity, diagrams and embeddings. In particular, the concept of causal diagram is given. Many explicit clarifying examples are presented throughout the paper

  15. Space-time as a causal set

    International Nuclear Information System (INIS)

    Bombelli, L.; Lee, J.; Meyer, D.; Sorkin, R.D.

    1987-01-01

    We propose that space-time at the smallest scales is in reality a causal set: a locally finite set of elements endowed with a partial order corresponding to the macroscopic relation that defines past and future. We explore how a Lorentzian manifold can approximate a causal set, noting in particular that the thereby defined effective dimensionality of a given causal set can vary with length scale. Finally, we speculate briefly on the quantum dynamics of causal sets, indicating why an appropriate choice of action can reproduce general relativity in the classical limit

  16. Amodal causal capture in the tunnel effect.

    Science.gov (United States)

    Bae, Gi Yeul; Flombaum, Jonathan I

    2011-01-01

    In addition to identifying individual objects in the world, the visual system must also characterize the relationships between objects, for instance when objects occlude one another or cause one another to move. Here we explored the relationship between perceived causality and occlusion. Can one perceive causality in an occluded location? In several experiments, observers judged whether a centrally presented event involved a single object passing behind an occluder, or one object causally launching another (out of view and behind the occluder). With no additional context, the centrally presented event was typically judged as a non-causal pass, even when the occluding and disoccluding objects were different colors--an illusion known as the 'tunnel effect' that results from spatiotemporal continuity. However, when a synchronized context event involved an unambiguous causal launch, participants perceived a causal launch behind the occluder. This percept of an occluded causal interaction could also be driven by grouping and synchrony cues in the absence of any explicitly causal interaction. These results reinforce the hypothesis that causality is an aspect of perception. It is among the interpretations of the world that are independently available to vision when resolving ambiguity, and that the visual system can 'fill in' amodally.

  17. Electromagnetic pulses, localized and causal

    Science.gov (United States)

    Lekner, John

    2018-01-01

    We show that pulse solutions of the wave equation can be expressed as time Fourier superpositions of scalar monochromatic beam wave functions (solutions of the Helmholtz equation). This formulation is shown to be equivalent to Bateman's integral expression for solutions of the wave equation, for axially symmetric solutions. A closed-form one-parameter solution of the wave equation, containing no backward-propagating parts, is constructed from a beam which is the tight-focus limit of two families of beams. Application is made to transverse electric and transverse magnetic pulses, with evaluation of the energy, momentum and angular momentum for a pulse based on the general localized and causal form. Such pulses can be represented as superpositions of photons. Explicit total energy and total momentum values are given for the one-parameter closed-form pulse.

  18. Quantum retrodiction and causality principle

    International Nuclear Information System (INIS)

    Shirokov, M.I.

    1994-01-01

    Quantum mechanics is factually a predictive science. But quantum retrodiction may also be needed, e.g., for the experimental verification of the validity of the Schroedinger equation for the wave function in the past if the present state is given. It is shown that in the retrodictive analog of the prediction the measurement must be replaced by another physical process called the retromeasurement. In this process, the reduction of a state vector into eigenvectors of a measured observable must proceed in the opposite direction of time as compared to the usual reduction. Examples of such processes are unknown. Moreover, they are shown to be forbidden by the causality principle stating that the later event cannot influence the earlier one. So quantum retrodiction seems to be unrealizable. It is demonstrated that the approach to the retrodiction given by S.Watanabe and F.Belinfante must be considered as an unsatisfactory ersatz of retrodicting. 20 refs., 3 figs

  19. Novas linhagens de repôlho e couve-flor para o Estado de São Paulo Improved cabbage and cauliflower types for São Paulo

    Directory of Open Access Journals (Sweden)

    Leocádio de Souza Camargo

    1956-01-01

    Full Text Available A experimentação com repôlho (Brassica oleracea L. var. capitata L. e couve-flor (B. oleracea L. var. botrytis cauliflora, Gars, D.C. foi intensificada no Instituto Agronômico a partir de 1941 e, em 1944 iniciaram-se os trabalhos sôbre o seu melhoramento. No presente trabalho são feitas referências sobre florescimento, polinização, genética, problemas da produção de sementes, deficiência de boro, época de semeação para produção de cabeças e de sementes, pragas e moléstias. Experimentaram-se 74 variedades de repôlho e 59 de couve-flor. O maior grupo de variedades produz bem na época fresca do ano, quando as temperaturas médias mensais variam em tôrno de 22,5°C durante o crescimento, e de 16,5°C, na época de formação de cabeças. Para plantio na época quente do ano, com temperaturas médias mensais variando de 20,4 a 22,6°C, durante o crescimento, e de 18 a 22,2°C, na formação de cabeças, prestam-se a variedade de repôlho paulista "Louco" (I.A.C. n.° 758 melhorada no Instituto Agronômico, e a couve-flor "Early Benares", n.° 1383, procedente de Sutton's Seed, Índia, também adaptada às nossas condições climáticas. Em 1944 iniciou-se em Campinas, na E. E. Central, o melhoramento do repolho "Louco" com material procedente de Mogí das Cruzes, São Paulo. Seus defeitos foram eliminados, possuindo-se dêle boas linhagens. Dêsse repôlho foram produzidas, em campos de cooperação da Divisão de Fomento Agrícola, em 1950 e 1951, respectivamente 750 e 722,5 kg de sementes, obtendo-se em média, 26,5 g por planta ou 53 g por m2. Visando à produção de sementes, a melhor época de semeadura é dezembro. As cabeças formam-se em março e abril; após a retirada da cabeça as gemas do caule brotam; desses brotos, dois dos mais fortes devem ficar para a produção de sementes. O florescimento e a colheita das sementes dão-se em épocas favoráveis. As sementes são colhidas desde 160 dias após o corte da cabe

  20. Causal ubiquity in quantum physics. A superluminal and local-causal physical ontology

    International Nuclear Information System (INIS)

    Neelamkavil, Raphael

    2014-01-01

    A fixed highest criterial velocity (of light) in STR (special theory of relativity) is a convention for a layer of physical inquiry. QM (Quantum Mechanics) avoids action-at-a-distance using this concept, but accepts non-causality and action-at-a-distance in EPR (Einstein-Podolsky-Rosen-Paradox) entanglement experiments. Even in such allegedly [non-causal] processes, something exists processually in extension-motion, between the causal and the [non-causal]. If STR theoretically allows real-valued superluminal communication between EPR entangled particles, quantum processes become fully causal. That is, the QM world is sub-luminally, luminally and superluminally local-causal throughout, and the Law of Causality is ubiquitous in the micro-world. Thus, ''probabilistic causality'' is a merely epistemic term.

  1. Causal ubiquity in quantum physics. A superluminal and local-causal physical ontology

    Energy Technology Data Exchange (ETDEWEB)

    Neelamkavil, Raphael

    2014-07-01

    A fixed highest criterial velocity (of light) in STR (special theory of relativity) is a convention for a layer of physical inquiry. QM (Quantum Mechanics) avoids action-at-a-distance using this concept, but accepts non-causality and action-at-a-distance in EPR (Einstein-Podolsky-Rosen-Paradox) entanglement experiments. Even in such allegedly [non-causal] processes, something exists processually in extension-motion, between the causal and the [non-causal]. If STR theoretically allows real-valued superluminal communication between EPR entangled particles, quantum processes become fully causal. That is, the QM world is sub-luminally, luminally and superluminally local-causal throughout, and the Law of Causality is ubiquitous in the micro-world. Thus, ''probabilistic causality'' is a merely epistemic term.

  2. Caracterización florística y estructural de tres fragmentos boscosos secundarios en Cartago, Costa Rica

    Directory of Open Access Journals (Sweden)

    Carlos O Morales

    2009-11-01

    Full Text Available Se realizaron observaciones sobre sucesión y composición florística en 25 parcelas de 10 m x 2 m en tres fragmentos boscosos secundarios, contiguos, del Jardín Botánico Lankester, Costa Rica. La intervención humana fue positiva en la regeneración de estos fragmentos por 1 protección de una antigua área de cultivo y pastoreo desde 1970, y 2 siembra y propagación de especies vegetales. Se comprobó que el cultivo de plantas nativas e introducidas de crecimiento exitoso puede acelerar el proceso de regeneración, impedir la dominancia de especies pioneras o invasoras y aumentar la diversidad de especies más rápidamente que en procesos comunes de sucesión. La diversificación natural se redujo a medida que la vegetación natural de los alrededores de los fragmentos fue desapareciendo, con una consecuente disminución o erradicación de semillas y otros propágulos, tales como esporas y tallos. Especies introducidas se naturalizaron en estos bosques, se propagan fácilmente y algunas son invasoras. Este estudio propone pautas generales para facilitar la regeneración de bosques neotropicales al combinar regeneración natural y cultivo de especies nativas.

  3. A Theory of Causal Learning in Children: Causal Maps and Bayes Nets

    Science.gov (United States)

    Gopnik, Alison; Glymour, Clark; Sobel, David M.; Schulz, Laura E.; Kushnir, Tamar; Danks, David

    2004-01-01

    The authors outline a cognitive and computational account of causal learning in children. They propose that children use specialized cognitive systems that allow them to recover an accurate "causal map" of the world: an abstract, coherent, learned representation of the causal relations among events. This kind of knowledge can be perspicuously…

  4. Further properties of causal relationship: causal structure stability, new criteria for isocausality and counterexamples

    International Nuclear Information System (INIS)

    Garcia-Parrado, Alfonso; Sanchez, Miguel

    2005-01-01

    Recently (Garcia-Parrado and Senovilla 2003 Class. Quantum Grav. 20 625-64) the concept of causal mapping between spacetimes, essentially equivalent in this context to the chronological map defined in abstract chronological spaces, and the related notion of causal structure, have been introduced as new tools to study causality in Lorentzian geometry. In the present paper, these tools are further developed in several directions such as (i) causal mappings-and, thus, abstract chronological ones-do not preserve two levels of the standard hierarchy of causality conditions (however, they preserve the remaining levels as shown in the above reference), (ii) even though global hyperbolicity is a stable property (in the set of all time-oriented Lorentzian metrics on a fixed manifold), the causal structure of a globally hyperbolic spacetime can be unstable against perturbations; in fact, we show that the causal structures of Minkowski and Einstein static spacetimes remain stable, whereas that of de Sitter becomes unstable, (iii) general criteria allow us to discriminate different causal structures in some general spacetimes (e.g. globally hyperbolic, stationary standard); in particular, there are infinitely many different globally hyperbolic causal structures (and thus, different conformal ones) on R 2 (iv) plane waves with the same number of positive eigenvalues in the frequency matrix share the same causal structure and, thus, they have equal causal extensions and causal boundaries

  5. Campbell's and Rubin's Perspectives on Causal Inference

    Science.gov (United States)

    West, Stephen G.; Thoemmes, Felix

    2010-01-01

    Donald Campbell's approach to causal inference (D. T. Campbell, 1957; W. R. Shadish, T. D. Cook, & D. T. Campbell, 2002) is widely used in psychology and education, whereas Donald Rubin's causal model (P. W. Holland, 1986; D. B. Rubin, 1974, 2005) is widely used in economics, statistics, medicine, and public health. Campbell's approach focuses on…

  6. mediation: R Package for Causal Mediation Analysis

    Directory of Open Access Journals (Sweden)

    Dustin Tingley

    2014-09-01

    Full Text Available In this paper, we describe the R package mediation for conducting causal mediation analysis in applied empirical research. In many scientific disciplines, the goal of researchers is not only estimating causal effects of a treatment but also understanding the process in which the treatment causally affects the outcome. Causal mediation analysis is frequently used to assess potential causal mechanisms. The mediation package implements a comprehensive suite of statistical tools for conducting such an analysis. The package is organized into two distinct approaches. Using the model-based approach, researchers can estimate causal mediation effects and conduct sensitivity analysis under the standard research design. Furthermore, the design-based approach provides several analysis tools that are applicable under different experimental designs. This approach requires weaker assumptions than the model-based approach. We also implement a statistical method for dealing with multiple (causally dependent mediators, which are often encountered in practice. Finally, the package also offers a methodology for assessing causal mediation in the presence of treatment noncompliance, a common problem in randomized trials.

  7. Causal Mediation Analysis: Warning! Assumptions Ahead

    Science.gov (United States)

    Keele, Luke

    2015-01-01

    In policy evaluations, interest may focus on why a particular treatment works. One tool for understanding why treatments work is causal mediation analysis. In this essay, I focus on the assumptions needed to estimate mediation effects. I show that there is no "gold standard" method for the identification of causal mediation effects. In…

  8. A General Approach to Causal Mediation Analysis

    Science.gov (United States)

    Imai, Kosuke; Keele, Luke; Tingley, Dustin

    2010-01-01

    Traditionally in the social sciences, causal mediation analysis has been formulated, understood, and implemented within the framework of linear structural equation models. We argue and demonstrate that this is problematic for 3 reasons: the lack of a general definition of causal mediation effects independent of a particular statistical model, the…

  9. A Causal Model of Faculty Research Productivity.

    Science.gov (United States)

    Bean, John P.

    A causal model of faculty research productivity was developed through a survey of the literature. Models of organizational behavior, organizational effectiveness, and motivation were synthesized into a causal model of productivity. Two general types of variables were assumed to affect individual research productivity: institutional variables and…

  10. Counterfactual overdetermination vs. the causal exclusion problem.

    Science.gov (United States)

    Sparber, Georg

    2005-01-01

    This paper aims to show that a counterfactual approach to causation is not sufficient to provide a solution to the causal exclusion problem in the form of systematic overdetermination. Taking into account the truthmakers of causal counterfactuals provides a strong argument in favour of the identity of causes in situations of translevel, causation.

  11. Causal Indicators Can Help to Interpret Factors

    Science.gov (United States)

    Bentler, Peter M.

    2016-01-01

    The latent factor in a causal indicator model is no more than the latent factor of the factor part of the model. However, if the causal indicator variables are well-understood and help to improve the prediction of individuals' factor scores, they can help to interpret the meaning of the latent factor. Aguirre-Urreta, Rönkkö, and Marakas (2016)…

  12. Quasi-Experimental Designs for Causal Inference

    Science.gov (United States)

    Kim, Yongnam; Steiner, Peter

    2016-01-01

    When randomized experiments are infeasible, quasi-experimental designs can be exploited to evaluate causal treatment effects. The strongest quasi-experimental designs for causal inference are regression discontinuity designs, instrumental variable designs, matching and propensity score designs, and comparative interrupted time series designs. This…

  13. Determining Directional Dependency in Causal Associations

    Science.gov (United States)

    Pornprasertmanit, Sunthud; Little, Todd D.

    2012-01-01

    Directional dependency is a method to determine the likely causal direction of effect between two variables. This article aims to critique and improve upon the use of directional dependency as a technique to infer causal associations. We comment on several issues raised by von Eye and DeShon (2012), including: encouraging the use of the signs of…

  14. Levantamento florístico de uma mata decídua em Uberlândia, Minas Gerais, Brasil Floriste survey of an area of deciduous forest in Uberlândia, Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Luciene Alves Rodrigues

    1997-12-01

    Full Text Available Esse trabalho consistiu de levantamento florístico em mata mesófila decídua situada em solo raso de origem basáltica em Uberlândia, Minas Gerais. Foram feitas visitas quinzenais à mata, no período de fevereiro/93 a junho/95, para coletas de exemplares botânicos férteis. O material coletado foi incorporado ao Herbário da Universidade Federal de Uberlândia (HUFU. Foram identificadas 105 espécies de árvores, arbustos, lianas e herbáceas, distribuídas em 88 gêneros e 43 famílias. As espécies mais freqüentes na mata foram: Anadenanthera colubrina, Bauhinia sp., Croton sp., Myracrodruon urundeuva e Sweetiafruticosa. Euphorbiaceae (10, Rubiaceae (8, Mimosaceae (6, Myrtaceae (6, Caesalpinaceae (5 e Fabaceae (5 foram as famílias com maior número de espécies identificadas.A floristic survey was carried out in a deciduous forest on a shallow basaltic soil, in Uberlândia, Minas Gerais. Visits were performed fortnightly from February/93 to June/95. The sampled material was lodged at the Herbarium of the Universidade Federal de Uberlândia (HUFU. A list is provided with 105 species of trees, shrubs, scandent shrubs, lianas and herbs, belonging to 88 genera and 43 botanic families. The most frequent species were: Anadenanthera colubrina, Bauhinia sp., Croton sp., Myracrodruon urundeuva and Sweetia fruticosa. Euphorbiaceae (10, Rubiaceae (8, Mimosaceae (6, Myrtaceae (6, Caesalpinaceae (5 e Fabaceae (5 were the families with the largest numbers of identified species.

  15. Heterogeneous Causal Effects and Sample Selection Bias

    DEFF Research Database (Denmark)

    Breen, Richard; Choi, Seongsoo; Holm, Anders

    2015-01-01

    The role of education in the process of socioeconomic attainment is a topic of long standing interest to sociologists and economists. Recently there has been growing interest not only in estimating the average causal effect of education on outcomes such as earnings, but also in estimating how...... causal effects might vary over individuals or groups. In this paper we point out one of the under-appreciated hazards of seeking to estimate heterogeneous causal effects: conventional selection bias (that is, selection on baseline differences) can easily be mistaken for heterogeneity of causal effects....... This might lead us to find heterogeneous effects when the true effect is homogenous, or to wrongly estimate not only the magnitude but also the sign of heterogeneous effects. We apply a test for the robustness of heterogeneous causal effects in the face of varying degrees and patterns of selection bias...

  16. Repair of Partly Misspecified Causal Diagrams.

    Science.gov (United States)

    Oates, Chris J; Kasza, Jessica; Simpson, Julie A; Forbes, Andrew B

    2017-07-01

    Errors in causal diagrams elicited from experts can lead to the omission of important confounding variables from adjustment sets and render causal inferences invalid. In this report, a novel method is presented that repairs a misspecified causal diagram through the addition of edges. These edges are determined using a data-driven approach designed to provide improved statistical efficiency relative to de novo structure learning methods. Our main assumption is that the expert is "directionally informed," meaning that "false" edges provided by the expert would not create cycles if added to the "true" causal diagram. The overall procedure is cast as a preprocessing technique that is agnostic to subsequent causal inferences. Results based on simulated data and data derived from an observational cohort illustrate the potential for data-assisted elicitation in epidemiologic applications. See video abstract at, http://links.lww.com/EDE/B208.

  17. Causality, spin, and equal-time commutators

    International Nuclear Information System (INIS)

    Abdel-Rahman, A.M.

    1975-01-01

    We study the causality constraints on the structure of the Lorentz-antisymmetric component of the commutator of two conserved isovector currents between fermion states of equal momenta. We discuss the sum rules that follow from causality and scaling, using the recently introduced refined infinite-momentum technique. The complete set of sum rules is found to include the spin-dependent fixed-mass sum rules obtained from light-cone commutators. The causality and scaling restrictions on the structure of the electromagnetic equal-time commutators are discussed, and it is found, in particular, that causality requires the spin-dependent part of the matrix element for the time-space electromagnetic equal-time commutator to vanish identically. It is also shown, in comparison with the electromagnetic case, that the corresponding matrix element for the time-space isovector current equal-time commutator is required, by causality, to have isospin-antisymmetric tensor and scalar operator Schwinger terms

  18. Causal ubiquity in quantum physics a superluminal and local-causal physical ontology

    CERN Document Server

    Neelamkavil, Raphael

    2014-01-01

    A fixed highest criterial velocity (of light) in STR (special theory of relativity) is a convention for a layer of physical inquiry. QM (Quantum Mechanics) avoids action-at-a-distance using this concept, but accepts non-causality and action-at-a-distance in EPR (Einstein-Podolsky-Rosen-Paradox) entanglement experiments. Even in such allegedly non-causal processes, something exists processually in extension-motion, between the causal and the non-causal. If STR theoretically allows real-valued superluminal communication between EPR entangled particles, quantum processes become fully causal. That

  19. Causality violations in Lovelock theories

    Science.gov (United States)

    Brustein, Ram; Sherf, Yotam

    2018-04-01

    Higher-derivative gravity theories, such as Lovelock theories, generalize Einstein's general relativity (GR). Modifications to GR are expected when curvatures are near Planckian and appear in string theory or supergravity. But can such theories describe gravity on length scales much larger than the Planck cutoff length scale? Here we find causality constraints on Lovelock theories that arise from the requirement that the equations of motion (EOM) of perturbations be hyperbolic. We find a general expression for the "effective metric" in field space when Lovelock theories are perturbed around some symmetric background solution. In particular, we calculate explicitly the effective metric for a general Lovelock theory perturbed around cosmological Friedman-Robertson-Walker backgrounds and for some specific cases when perturbed around Schwarzschild-like solutions. For the EOM to be hyperbolic, the effective metric needs to be Lorentzian. We find that, unlike for GR, the effective metric is generically not Lorentzian when the Lovelock modifications are significant. So, we conclude that Lovelock theories can only be considered as perturbative extensions of GR and not as truly modified theories of gravity. We compare our results to those in the literature and find that they agree with and reproduce the results of previous studies.

  20. Causal localizations in relativistic quantum mechanics

    Science.gov (United States)

    Castrigiano, Domenico P. L.; Leiseifer, Andreas D.

    2015-07-01

    Causal localizations describe the position of quantum systems moving not faster than light. They are constructed for the systems with finite spinor dimension. At the center of interest are the massive relativistic systems. For every positive mass, there is the sequence of Dirac tensor-localizations, which provides a complete set of inequivalent irreducible causal localizations. They obey the principle of special relativity and are fully Poincaré covariant. The boosters are determined by the causal position operator and the other Poincaré generators. The localization with minimal spinor dimension is the Dirac localization. Thus, the Dirac equation is derived here as a mere consequence of the principle of causality. Moreover, the higher tensor-localizations, not known so far, follow from Dirac's localization by a simple construction. The probability of localization for positive energy states results to be described by causal positive operator valued (PO-) localizations, which are the traces of the causal localizations on the subspaces of positive energy. These causal Poincaré covariant PO-localizations for every irreducible massive relativistic system were, all the more, not known before. They are shown to be separated. Hence, the positive energy systems can be localized within every open region by a suitable preparation as accurately as desired. Finally, the attempt is made to provide an interpretation of the PO-localization operators within the frame of conventional quantum mechanics attributing an important role to the negative energy states.

  1. Causal inference, probability theory, and graphical insights.

    Science.gov (United States)

    Baker, Stuart G

    2013-11-10

    Causal inference from observational studies is a fundamental topic in biostatistics. The causal graph literature typically views probability theory as insufficient to express causal concepts in observational studies. In contrast, the view here is that probability theory is a desirable and sufficient basis for many topics in causal inference for the following two reasons. First, probability theory is generally more flexible than causal graphs: Besides explaining such causal graph topics as M-bias (adjusting for a collider) and bias amplification and attenuation (when adjusting for instrumental variable), probability theory is also the foundation of the paired availability design for historical controls, which does not fit into a causal graph framework. Second, probability theory is the basis for insightful graphical displays including the BK-Plot for understanding Simpson's paradox with a binary confounder, the BK2-Plot for understanding bias amplification and attenuation in the presence of an unobserved binary confounder, and the PAD-Plot for understanding the principal stratification component of the paired availability design. Published 2013. This article is a US Government work and is in the public domain in the USA.

  2. Análisis florístico del Parque Nacional Natural Amacayucu e Isla Mocagua, Amazonas (Colombia

    Directory of Open Access Journals (Sweden)

    Rudas L. Agustín

    1998-11-01

    Full Text Available A floristic study of the Parque Nacional Natural Amacayacu and Isla Mocagua shows 1348 species, 574 genera and 128 families of vascular plants; 82% of the species are dicotyledons, 14% monocotyledons, 3.7% ferns and ca. 0.2% gymnosperms. Leguminosae, Rubiaceae, Melastomataceae, Moraceae and Annonaceae represent 33% of the dicotyledonous species, whereas Araceae, Arecaceae and Poaceae are the main monocotyledonous families. Most families are Gondwanaland elements with sorne Laurasian elements; others are of unknown origino The main habit is represented by trees and shrubs (47% and 19% of the species, 25% are vines and herbs, 9% epiphytes and hemiepiphytes, and En un estudio florístico en cinco sectores del Parque Nacional Natural Amacayacu y en la Isla Mocagua, se encontraron 1348 especies de plantas vasculares, distribuidas en 574 géneros y 128 familias; 82% de las especies corresponden a dicotiledóneas, 14% a monocotiledóneas, 3.7% a pteridófitos y ca. de 0.2% a  gimnospermas. Las principales familias fueron Leguminosae, Rubiaceae, Melastomataceae, Moraceae y Annonaceae  (dicotiledóneas, y Araceae, Arecaceae y Poaceae (monocotiledóneas. La mayoría de las familias corresponde a elementos de Gondwana con algunos elementos Laurásicos y otros sin origen asignado. El mayor número de las especies tienen hábito arbóreo o arbustivo (47% y 19% respectivamente, ca. del 25% de las especies son lianas y hierbas, 9% epífitas y hemiepífitas, mientras que las parásitas y saprófitas apenas representan < 1%. Los bosques de tierra firme presentan casi el doble de especies de arbustos, hierbas y epífitos que las planicies inundables. Algunos sectores del Parque relativamente distantes entre sí presentan una gran similaridad en cuanto a composición florística, hecho que puede atribuirse principalmente al tipo de agua (blanca, negra o mixta que los irriga. Una comparación con regiones similares en el corredor pacífico, el piedemonte amaz

  3. Can chance cause cancer? A causal consideration.

    Science.gov (United States)

    Stensrud, Mats Julius; Strohmaier, Susanne; Valberg, Morten; Aalen, Odd Olai

    2017-04-01

    The role of randomness, environment and genetics in cancer development is debated. We approach the discussion by using the potential outcomes framework for causal inference. By briefly considering the underlying assumptions, we suggest that the antagonising views arise due to estimation of substantially different causal effects. These effects may be hard to interpret, and the results cannot be immediately compared. Indeed, it is not clear whether it is possible to define a causal effect of chance at all. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Dual Causality and the Autonomy of Biology.

    Science.gov (United States)

    Bock, Walter J

    2017-03-01

    Ernst Mayr's concept of dual causality in biology with the two forms of causes (proximate and ultimate) continues to provide an essential foundation for the philosophy of biology. They are equivalent to functional (=proximate) and evolutionary (=ultimate) causes with both required for full biological explanations. The natural sciences can be classified into nomological, historical nomological and historical dual causality, the last including only biology. Because evolutionary causality is unique to biology and must be included for all complete biological explanations, biology is autonomous from the physical sciences.

  5. Mathematical implications of Einstein-Weyl causality

    International Nuclear Information System (INIS)

    Borchers, H.J.; Sen, R.N.

    2006-01-01

    The present work is the first systematic attempt at answering the following fundamental question: what mathematical structures does Einstein-Weyl causality impose on a point-set that has no other previous structure defined on it? The authors propose an axiomatization of Einstein-Weyl causality (inspired by physics), and investigate the topological and uniform structures that it implies. Their final result is that a causal space is densely embedded in one that is locally a differentiable manifold. The mathematical level required of the reader is that of the graduate student in mathematical physics. (orig.)

  6. The mistake of the causal relationship

    Directory of Open Access Journals (Sweden)

    О. Д. Комаров

    2015-03-01

    Full Text Available The article deals with issues of the mistake of the causal relationship. The modern criminal law science approaches to the content of the mistake of the causal relationship and its significance to the qualification of the crime are described. It is proved that in cases of dolus generalis different mental attitude of the guilty person to two separate acts of his conduct exist. Consequently, in mentioned above cases mistake of the causal relationship does not have place. The rules of qualification of the crimes commited with the mistake of causation and in cases of dolus generalis are proposed .

  7. Estudios florísticos y ecológicos sobre las algas de agua dulce de turberas de Tierra del Fuego

    OpenAIRE

    Mataloni, María Gabriela

    1994-01-01

    En esta Tesis Doctoral se realizan diversas investigaciones florísticas y ecológicas sobre las algas de turberas de Sphagnum de la provincia de Tierra Fuego. Para ello se condijeron básicamente dos trabajos. en la primera parte se estudiaron ocho ojos de agua pertenecientes a siete turberas ubicadas en el sur de Tierra del Fuego. En cada una de ellas se muestrearon tanto el fitoplancton del agua libre como las algas que viven asociadas a Sphagnum a lo largo de un gradiente ambiental caracteri...

  8. Florística e fitossociologia de uma floresta de vertente na Amazônia Central, Amazonas, Brasil Floristic and phytosociology of a slope forest in Central Amazonia, Amazonas, Brazil

    Directory of Open Access Journals (Sweden)

    Arlem Nascimento de Oliveira

    2004-01-01

    Full Text Available O estudo florístico e fitossociológico de árvores, palmeiras e lianas com diâmetro à altura do peito (DAP >10 cm, em uma floresta de vertente na Amazônia Central (2º35'45" S e 60º12'40" W, foi realizado empregando-se 20 parcelas de 50 x 10 m, distribuídas em dois transectos paralelos de 500 x 10 m. Foram registrados 771 indivíduos, pertencentes a 50 famílias, 120 gêneros e 239 espécies. Das espécies amostradas, 44% são "localmente raras". Sapotaceae, Lecythidaceae, Fabaceae, Caesalpiniaceae e Chrysobalanaceae constituíram as cinco famílias com maior riqueza de espécies e número de indivíduos. Dos 771 indivíduos amostrados, mais de 65% apresentaram DAP > 20 cm. As espécies Eschweilera bracteosa e Protium apiculatum apresentaram os maiores valores de IVI. Cerca de 83% das espécies encontram-se distribuídas aleatoriamente no hectare amostrado. O índice de diversidade Shannon-Wiener foi de 5,01 nats.indivíduo-1, com uniformidade de 0,91, valores altos no contexto de levantamentos semelhantes na região. A heterogeneidade edáfica e topográfica da área, as taxas de recrutamento de novos indivíduos e de espécies "localmente raras" à comunidade local, podem ter contribuído para as altas dissimilaridade (36,2% e diversidade florísticas documentadas neste estudo.The floristic and phytosociological study of trees, palms and lianas with diameter at breast height (DBH >10 cm in a forest slope in Central Amazonia (2º35'45 "S and 60º12'40" W was carried out using 20 plots of 50 x 10 m, distributed in two parallel transects of 500 x 10 m. A total of 771 plants were registered, belonging to 50 families, 120 genera and 239 species. Of the sampled species, 44% are locally rare. Families with the most species and number of individuals were Sapotaceae, Lecythidaceae, Fabaceae, Caesalpiniaceae and Chrysobalanaceae. More than 65% of the sampled plants had DBH > 20 cm. Eschweilera bracteosa and Protium apiculatum were the most

  9. Assessing students' beliefs, emotions and causal attribution ...

    African Journals Online (AJOL)

    Keywords: academic emotion; belief; causal attribution; statistical validation; students' conceptions of learning ... Sadi & Lee, 2015), through their effect on motivation and learning strategies .... to understand why they may or may not be doing.

  10. Granger Causality Testing with Intensive Longitudinal Data.

    Science.gov (United States)

    Molenaar, Peter C M

    2018-06-01

    The availability of intensive longitudinal data obtained by means of ambulatory assessment opens up new prospects for prevention research in that it allows the derivation of subject-specific dynamic networks of interacting variables by means of vector autoregressive (VAR) modeling. The dynamic networks thus obtained can be subjected to Granger causality testing in order to identify causal relations among the observed time-dependent variables. VARs have two equivalent representations: standard and structural. Results obtained with Granger causality testing depend upon which representation is chosen, yet no criteria exist on which this important choice can be based. A new equivalent representation is introduced called hybrid VARs with which the best representation can be chosen in a data-driven way. Partial directed coherence, a frequency-domain statistic for Granger causality testing, is shown to perform optimally when based on hybrid VARs. An application to real data is provided.

  11. Causality Between Urban Concentration and Environmental Quality

    Directory of Open Access Journals (Sweden)

    Amin Pujiati

    2015-08-01

    Full Text Available Population is concentrated in urban areas can cause the external diseconomies on environment if it exceeds the carrying capacity of the space and the urban economy. Otherwise the quality of the environment is getting better, led to the concentration of population in urban areas are increasingly high. This study aims to analyze the relationship of causality between the urban concentration and environmental quality in urban agglomeration areas. The data used in the study of secondary data obtained from the Central Bureau of statistics and the City Government from 2000 to 2013. The analytical method used is the Granger causality and descriptive. Granger causality study results showed no pattern of reciprocal causality, between urban concentration and the quality of the environment, but there unidirectional relationship between the urban concentration and environmental quality. This means that increasing urban concentration led to decreased environmental quality.

  12. Selecting appropriate cases when tracing causal mechanisms

    DEFF Research Database (Denmark)

    Beach, Derek; Pedersen, Rasmus Brun

    2016-01-01

    The last decade has witnessed resurgence in the interest in studying the causal mechanisms linking causes and outcomes in the social sciences. This article explores the overlooked implications for case selection when tracing mechanisms using in-depth case studies. Our argument is that existing case...... selection guidelines are appropriate for research aimed at making cross-case claims about causal relationships, where case selection is primarily used to control for other causes. However, existing guidelines are not in alignment with case-based research that aims to trace mechanisms, where the goal...... is to unpack the causal mechanism between X and Y, enabling causal inferences to be made because empirical evidence is provided for how the mechanism actually operated in a particular case. The in-depth, within-case tracing of how mechanisms operate in particular cases produces what can be termed mechanistic...

  13. Rate-Agnostic (Causal) Structure Learning.

    Science.gov (United States)

    Plis, Sergey; Danks, David; Freeman, Cynthia; Calhoun, Vince

    2015-12-01

    Causal structure learning from time series data is a major scientific challenge. Extant algorithms assume that measurements occur sufficiently quickly; more precisely, they assume approximately equal system and measurement timescales. In many domains, however, measurements occur at a significantly slower rate than the underlying system changes, but the size of the timescale mismatch is often unknown. This paper develops three causal structure learning algorithms, each of which discovers all dynamic causal graphs that explain the observed measurement data, perhaps given undersampling. That is, these algorithms all learn causal structure in a "rate-agnostic" manner: they do not assume any particular relation between the measurement and system timescales. We apply these algorithms to data from simulations to gain insight into the challenge of undersampling.

  14. K-causality and degenerate spacetimes

    Science.gov (United States)

    Dowker, H. F.; Garcia, R. S.; Surya, S.

    2000-11-01

    The causal relation K+ was introduced by Sorkin and Woolgar to extend the standard causal analysis of C2 spacetimes to those that are only C0. Most of their results also hold true in the case of metrics with degeneracies which are C0 but vanish at isolated points. In this paper we seek to examine K+ explicitly in the case of topology-changing `Morse histories' which contain degeneracies. We first demonstrate some interesting features of this relation in globally Lorentzian spacetimes. In particular, we show that K+ is robust and the Hawking and Sachs characterization of causal continuity translates into a natural condition in terms of K+. We then examine K+ in topology-changing Morse spacetimes with the degenerate points excised and then for the Morse histories in which the degenerate points are reinstated. We find further characterizations of causal continuity in these cases.

  15. Efficient nonparametric estimation of causal mediation effects

    OpenAIRE

    Chan, K. C. G.; Imai, K.; Yam, S. C. P.; Zhang, Z.

    2016-01-01

    An essential goal of program evaluation and scientific research is the investigation of causal mechanisms. Over the past several decades, causal mediation analysis has been used in medical and social sciences to decompose the treatment effect into the natural direct and indirect effects. However, all of the existing mediation analysis methods rely on parametric modeling assumptions in one way or another, typically requiring researchers to specify multiple regression models involving the treat...

  16. Inference of Boundaries in Causal Sets

    OpenAIRE

    Cunningham, William

    2017-01-01

    We investigate the extrinsic geometry of causal sets in $(1+1)$-dimensional Minkowski spacetime. The properties of boundaries in an embedding space can be used not only to measure observables, but also to supplement the discrete action in the partition function via discretized Gibbons-Hawking-York boundary terms. We define several ways to represent a causal set using overlapping subsets, which then allows us to distinguish between null and non-null bounding hypersurfaces in an embedding space...

  17. The Continuum Limit of Causal Fermion Systems

    OpenAIRE

    Finster, Felix

    2016-01-01

    This monograph introduces the basic concepts of the theory of causal fermion systems, a recent approach to the description of fundamental physics. The theory yields quantum mechanics, general relativity and quantum field theory as limiting cases and is therefore a candidate for a unified physical theory. From the mathematical perspective, causal fermion systems provide a general framework for describing and analyzing non-smooth geometries and "quantum geometries." The dynamics is described by...

  18. Causal strength induction from time series data.

    Science.gov (United States)

    Soo, Kevin W; Rottman, Benjamin M

    2018-04-01

    One challenge when inferring the strength of cause-effect relations from time series data is that the cause and/or effect can exhibit temporal trends. If temporal trends are not accounted for, a learner could infer that a causal relation exists when it does not, or even infer that there is a positive causal relation when the relation is negative, or vice versa. We propose that learners use a simple heuristic to control for temporal trends-that they focus not on the states of the cause and effect at a given instant, but on how the cause and effect change from one observation to the next, which we call transitions. Six experiments were conducted to understand how people infer causal strength from time series data. We found that participants indeed use transitions in addition to states, which helps them to reach more accurate causal judgments (Experiments 1A and 1B). Participants use transitions more when the stimuli are presented in a naturalistic visual format than a numerical format (Experiment 2), and the effect of transitions is not driven by primacy or recency effects (Experiment 3). Finally, we found that participants primarily use the direction in which variables change rather than the magnitude of the change for estimating causal strength (Experiments 4 and 5). Collectively, these studies provide evidence that people often use a simple yet effective heuristic for inferring causal strength from time series data. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  19. Kant on causal laws and powers.

    Science.gov (United States)

    Henschen, Tobias

    2014-12-01

    The aim of the paper is threefold. Its first aim is to defend Eric Watkins's claim that for Kant, a cause is not an event but a causal power: a power that is borne by a substance, and that, when active, brings about its effect, i.e. a change of the states of another substance, by generating a continuous flow of intermediate states of that substance. The second aim of the paper is to argue against Watkins that the Kantian concept of causal power is not the pre-critical concept of real ground but the category of causality, and that Kant holds with Hume that causal laws cannot be inferred non-inductively (that he accordingly has no intention to show in the Second analogy or elsewhere that events fall under causal laws). The third aim of the paper is to compare the Kantian position on causality with central tenets of contemporary powers ontology: it argues that unlike the variants endorsed by contemporary powers theorists, the Kantian variants of these tenets are resistant to objections that neo-Humeans raise to these tenets.

  20. Causality violation, gravitational shockwaves and UV completion

    Energy Technology Data Exchange (ETDEWEB)

    Hollowood, Timothy J.; Shore, Graham M. [Department of Physics, Swansea University,Swansea, SA2 8PP (United Kingdom)

    2016-03-18

    The effective actions describing the low-energy dynamics of QFTs involving gravity generically exhibit causality violations. These may take the form of superluminal propagation or Shapiro time advances and allow the construction of “time machines”, i.e. spacetimes admitting closed non-spacelike curves. Here, we discuss critically whether such causality violations may be used as a criterion to identify unphysical effective actions or whether, and how, causality problems may be resolved by embedding the action in a fundamental, UV complete QFT. We study in detail the case of photon scattering in an Aichelburg-Sexl gravitational shockwave background and calculate the phase shifts in QED for all energies, demonstrating their smooth interpolation from the causality-violating effective action values at low-energy to their manifestly causal high-energy limits. At low energies, these phase shifts may be interpreted as backwards-in-time coordinate jumps as the photon encounters the shock wavefront, and we illustrate how the resulting causality problems emerge and are resolved in a two-shockwave time machine scenario. The implications of our results for ultra-high (Planck) energy scattering, in which graviton exchange is modelled by the shockwave background, are highlighted.

  1. Trepadeiras: florística da Estação Ecológica do Caiuá e chave de identificação vegetativa para espécies do Norte do Estado do Paraná - doi: 10.4025/actascibiolsci.v34i2.5892 Climbers: flora of the Caiuá Ecological Station and an identification key for the vegetative species of Northern Paraná State - doi: 10.4025/actascibiolsci.v34i2.5892

    Directory of Open Access Journals (Sweden)

    Juliana de Souza Carneiro

    2012-03-01

    Full Text Available As trepadeiras são plantas com alta representatividade nas florestas tropicais e de grande importância ecológica, apontadas como um dos fatores básicos que diferencia florestas tropicais de temperadas. Este trabalho apresenta as espécies de trepadeiras da Estação Ecológica do Caiuá (EECAIUÁ, município de Diamante do Norte, Estado do Paraná, inserida na floresta estacional semidecidual (FES submontana, situada à margem do rio Paranapanema. Foram encontradas 17 famílias, 44 gêneros e 53 espécies. As cinco famílias mais ricas em número de espécies perfazem juntas 57% do total encontrado. As trepadeiras herbáceas ocorrem em menor número quando comparadas às lianas, e quanto à estratégia utilizada para ascender, as volúveis são as mais diversas, seguidas pelas de órgãos preensores (gavinhas e escandentes. Uma chave de identificação para famílias, baseada em caracteres vegetativos, foi produzida para as famílias desta localidade com as famílias encontradas em outras duas no Norte do Paraná.Climbers are highly represented in tropical forests and are of great ecological importance, having been identified as one of the key factors that differentiate tropical forests from temperate rainforests. This paper presents the climber species of the Caiuá Ecological Station (EECAIUÁ in the City of Diamante do Norte, Paraná State; the Station is located in a submountainous seasonal semideciduous forest (SSF and is situated on the edge of the Paranapanema river. We found 17 families, 44 genera and 53 species of vines. The five families with the greatest number of species jointly accounted for 57% of the total species found. Herbaceous vines occurred less frequently than did lianas. When considering the climbing strategy used by the species, the graspers were the most diverse, followed by those that had tendrils (scramblers and climbers. An identification key based on vegetative characters of families found in other parts of

  2. Illness causal beliefs in Turkish immigrants

    Directory of Open Access Journals (Sweden)

    Klimidis Steven

    2007-07-01

    Full Text Available Abstract Background People hold a wide variety of beliefs concerning the causes of illness. Such beliefs vary across cultures and, among immigrants, may be influenced by many factors, including level of acculturation, gender, level of education, and experience of illness and treatment. This study examines illness causal beliefs in Turkish-immigrants in Australia. Methods Causal beliefs about somatic and mental illness were examined in a sample of 444 members of the Turkish population of Melbourne. The socio-demographic characteristics of the sample were broadly similar to those of the Melbourne Turkish community. Five issues were examined: the structure of causal beliefs; the relative frequency of natural, supernatural and metaphysical beliefs; ascription of somatic, mental, or both somatic and mental conditions to the various causes; the correlations of belief types with socio-demographic, modernizing and acculturation variables; and the relationship between causal beliefs and current illness. Results Principal components analysis revealed two broad factors, accounting for 58 percent of the variation in scores on illness belief scales, distinctly interpretable as natural and supernatural beliefs. Second, beliefs in natural causes were more frequent than beliefs in supernatural causes. Third, some causal beliefs were commonly linked to both somatic and mental conditions while others were regarded as more specific to either somatic or mental disorders. Last, there was a range of correlations between endorsement of belief types and factors defining heterogeneity within the community, including with demographic factors, indicators of modernizing and acculturative processes, and the current presence of illness. Conclusion Results supported the classification of causal beliefs proposed by Murdock, Wilson & Frederick, with a division into natural and supernatural causes. While belief in natural causes is more common, belief in supernatural causes

  3. Illness causal beliefs in Turkish immigrants.

    Science.gov (United States)

    Minas, Harry; Klimidis, Steven; Tuncer, Can

    2007-07-24

    People hold a wide variety of beliefs concerning the causes of illness. Such beliefs vary across cultures and, among immigrants, may be influenced by many factors, including level of acculturation, gender, level of education, and experience of illness and treatment. This study examines illness causal beliefs in Turkish-immigrants in Australia. Causal beliefs about somatic and mental illness were examined in a sample of 444 members of the Turkish population of Melbourne. The socio-demographic characteristics of the sample were broadly similar to those of the Melbourne Turkish community. Five issues were examined: the structure of causal beliefs; the relative frequency of natural, supernatural and metaphysical beliefs; ascription of somatic, mental, or both somatic and mental conditions to the various causes; the correlations of belief types with socio-demographic, modernizing and acculturation variables; and the relationship between causal beliefs and current illness. Principal components analysis revealed two broad factors, accounting for 58 percent of the variation in scores on illness belief scales, distinctly interpretable as natural and supernatural beliefs. Second, beliefs in natural causes were more frequent than beliefs in supernatural causes. Third, some causal beliefs were commonly linked to both somatic and mental conditions while others were regarded as more specific to either somatic or mental disorders. Last, there was a range of correlations between endorsement of belief types and factors defining heterogeneity within the community, including with demographic factors, indicators of modernizing and acculturative processes, and the current presence of illness. Results supported the classification of causal beliefs proposed by Murdock, Wilson & Frederick, with a division into natural and supernatural causes. While belief in natural causes is more common, belief in supernatural causes persists despite modernizing and acculturative influences. Different

  4. Florística das espécies arbóreas de quatro fragmentos de Floresta Estacional Semidecídua Montana na Fazenda Dona Carolina (Itatiba/Bragança Paulista, São Paulo, Brasil. Floristic of tree species of four fragments of semi-deciduous Seasonal Montana Forest in Dona Carolina Farm (Itatiba/Bragança Paulista, São Paulo, Brazil.

    Directory of Open Access Journals (Sweden)

    Roberta Macedo CERGUEIRA Leonardo Dias MEIRELES

    2008-06-01

    Full Text Available Realizou-se um levantamento florísticoem quatro fragmentos de Floresta EstacionalSemidecídua Montana na Fazenda Dona Carolina,localizada nos municípios de Itatiba e Bragança Paulista,São Paulo, Brasil (22º 56’ 16” S e 46º 42’ 02” W.A Fazenda localiza-se dentro da unidademorfoescultural do Planalto Atlântico, com climaCfa e altitudes entre 775 e 974 m. As espéciesarbóreas de altura 2 metros foram coletadas eidentificadas. Foram amostradas 157 espécies,distribuídas em 109 gêneros e 41 famílias. As famíliasFabaceae (24 spp., Myrtaceae (15 spp., Lauraceae(9 spp. e Meliaceae (9 spp. foram as mais ricasem espécies. A similaridade florística da área emestudo com Florestas Estacionais SemidecíduasMontanas e Submontanas do Estado de São Paulofoi verificada através do índice de Jaccard e dométodo de agrupamento por média de grupos(UPGMA. Uma Twinspan foi realizada paraverificar quais espécies caracterizariam os gruposformados. A área estudada apresentou altasimilaridade florística com os fragmentos localizadosno município de Campinas, não se agrupando como fragmento florestal amostrado no mesmomunicípio. A restauração de áreas degradadas e aconservação de fragmentos localizados nessa regiãodevem, então, considerar a composição florísticados fragmentos adjacentes.A floristic survey was carried out in fourfragments of Semideciduous Seasonal MontaneForest in Dona Carolina Farm, located in themunicipalities of Itatiba and Bragança Paulista,São Paulo, Brazil (22º 56’ 16” S e 46º 42’ 02” W.The Farm is within the Atlantic Plateaumorphosculptural unit, with climate Cfa, between775 and 974 m elevation. Only tree species 2 meters high were collected and identified.A total of 157 species distributed in 109 generaand 41 families were sampled. Fabaceae (24species, Myrtaceae (15, Lauraceae (9 and Meliaceae(9 were the richest families. The floristicsimilarity between the studied area and other Semideciduous

  5. Entanglement entropy in causal set theory

    Science.gov (United States)

    Sorkin, Rafael D.; Yazdi, Yasaman K.

    2018-04-01

    Entanglement entropy is now widely accepted as having deep connections with quantum gravity. It is therefore desirable to understand it in the context of causal sets, especially since they provide in a natural manner the UV cutoff needed to render entanglement entropy finite. Formulating a notion of entanglement entropy in a causal set is not straightforward because the type of canonical hypersurface-data on which its definition typically relies is not available. Instead, we appeal to the more global expression given in Sorkin (2012 (arXiv:1205.2953)) which, for a Gaussian scalar field, expresses the entropy of a spacetime region in terms of the field’s correlation function within that region (its ‘Wightman function’ W(x, x') ). Carrying this formula over to the causal set, one obtains an entropy which is both finite and of a Lorentz invariant nature. We evaluate this global entropy-expression numerically for certain regions (primarily order-intervals or ‘causal diamonds’) within causal sets of 1  +  1 dimensions. For the causal-set counterpart of the entanglement entropy, we obtain, in the first instance, a result that follows a (spacetime) volume law instead of the expected (spatial) area law. We find, however, that one obtains an area law if one truncates the commutator function (‘Pauli–Jordan operator’) and the Wightman function by projecting out the eigenmodes of the Pauli–Jordan operator whose eigenvalues are too close to zero according to a geometrical criterion which we describe more fully below. In connection with these results and the questions they raise, we also study the ‘entropy of coarse-graining’ generated by thinning out the causal set, and we compare it with what one obtains by similarly thinning out a chain of harmonic oscillators, finding the same, ‘universal’ behaviour in both cases.

  6. Caracterización florística y estructural de tres fragmentos boscosos secundarios en Cartago, Costa Rica

    Directory of Open Access Journals (Sweden)

    Carlos O Morales

    2009-11-01

    Full Text Available Se realizaron observaciones sobre sucesión y composición florística en 25 parcelas de 10 m x 2 m en tres fragmentos boscosos secundarios, contiguos, del Jardín Botánico Lankester, Costa Rica. La intervención humana fue positiva en la regeneración de estos fragmentos por 1 protección de una antigua área de cultivo y pastoreo desde 1970, y 2 siembra y propagación de especies vegetales. Se comprobó que el cultivo de plantas nativas e introducidas de crecimiento exitoso puede acelerar el proceso de regeneración, impedir la dominancia de especies pioneras o invasoras y aumentar la diversidad de especies más rápidamente que en procesos comunes de sucesión. La diversificación natural se redujo a medida que la vegetación natural de los alrededores de los fragmentos fue desapareciendo, con una consecuente disminución o erradicación de semillas y otros propágulos, tales como esporas y tallos. Especies introducidas se naturalizaron en estos bosques, se propagan fácilmente y algunas son invasoras. Este estudio propone pautas generales para facilitar la regeneración de bosques neotropicales al combinar regeneración natural y cultivo de especies nativas.Floristic and structural characterization of three secondary forest fragments in Costa Rica. Observations on successional development and floristic composition were made in 25 plots (10x2 m established in three contiguous secondary forest fragments of the Lankester Botanical Garden, Costa Rica. Human activities favored forest regeneration there by 1 protecting an abandoned farm and pasture area since 1970, and 2 planting and propagating plant species. Planting successfully growing native and introduced species can accelerate the succession process, avoid dominance of pioneer or invasive species, and increase species diversity faster than in common successional processes. Natural diversification slowed down as natural vegetation surrounding the secondary fragments was disappearing, with a

  7. Caracterização florística de uma área de contato entre Cerrado e Mata Atlântica na região sudoeste do Estado de São Paulo.

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    Nicole da Silva PINTO

    2012-06-01

    Full Text Available Remanescentes de vegetação nativa em áreas de contato florístico e fitogeográfico têm especial importância na conservação da biodiversidade. A EstaçãoExperimental de Itapeva – EExI apresenta os referidos atributos, pois, abriga remanescentes de Floresta Estacional Semidecidual e de Cerrado. A EExI está localizada na BaciaHidrográfica do Alto Paranapanema – BHAP, na região sudoeste do Estado de São Paulo, considerada altamente degradada e prioritária para estudos de flora e fauna. Os objetivos deste trabalho foram: inventariar e caracterizar a vegetação e a flora vascular da EExI; ampliar o conhecimento sobre a biodiversidade da BHAP e subsidiar propostas de manejo. Realizou-se a caracterização fisionômica e florística considerando todos os hábitos, com coletas mensais de material botânico, de maio de 2009 a dezembro de 2010. Nas duas formações presentes na EExI, Mata Atlântica (Floresta Estacional Semidecidual – FES e Cerrado (campo rupestre, campo sujo úmido, campo sujo, cerrado ralo e cerrado denso, foram registradas 605 espécies. As famílias mais ricasna FES foram: Fabaceae, Myrtaceae, Rubiaceae, Asteraceae e Lauraceae, e no Cerrado:Asteraceae, Fabaceae, Myrtaceae, Melastomataceae e Bignoniaceae. Na FES predominaramas espécies arbóreas com 54,1% do total, ao contrário do Cerrado, onde predominaram as espécies não arbóreas (67,5%. Entre as espécies levantadas, 14 estão ameaçadas de extinção, mas apenas Araucaria angustifolia é citada nas listas estadual, nacional e mundial. Considerando o mosaico de FES e fisionomias de Cerrado, a alta diversidade de espécies e a presença de espécies ameaçadas de extinção, os remanescentes de vegetação da EExI são de extrema importância para a conservação e o estudo da biodiversidade regional.Remnants of native vegetation in areas of floristic and phytogeographical contact have special importance in biodiversity conservation. The Itapeva Experimental

  8. The Relevance of Causal Social Construction

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    Marques Teresa

    2017-02-01

    Full Text Available Social constructionist claims are surprising and interesting when they entail that presumably natural kinds are in fact socially constructed. The claims are interesting because of their theoretical and political importance. Authors like Díaz-León argue that constitutive social construction is more relevant for achieving social justice than causal social construction. This paper challenges this claim. Assuming there are socially salient groups that are discriminated against, the paper presents a dilemma: if there were no constitutively constructed social kinds, the causes of the discrimination of existing social groups would have to be addressed, and understanding causal social construction would be relevant to achieve social justice. On the other hand, not all possible constitutively socially constructed kinds are actual social kinds. If an existing social group is constitutively constructed as a social kind K, the fact that it actually exists as a K has social causes. Again, causal social construction is relevant. The paper argues that (i for any actual social kind X, if X is constitutively socially constructed as K, then it is also causally socially constructed; and (ii causal social construction is at least as relevant as constitutive social construction for concerns of social justice. For illustration, I draw upon two phenomena that are presumed to contribute towards the discrimination of women: (i the poor performance effects of stereotype threat, and (ii the silencing effects of gendered language use.

  9. Preschoolers prefer to learn causal information

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    Aubry eAlvarez

    2015-02-01

    Full Text Available Young children, in general, appear to have a strong drive to explore the environment in ways that reveal its underlying causal structure. But are they really attuned specifically to casual information in this quest for understanding, or do they show equal interest in other types of non-obvious information about the world? To answer this question, we introduced 20 three-year-old children to two puppets who were anxious to tell the child about a set of novel artifacts and animals. One puppet consistently described causal properties of the items while the other puppet consistently described carefully matched non-causal properties of the same items. After a familiarization period in which children learned which type of information to expect from each informant, children were given the opportunity to choose which they wanted to hear describe each of eight pictured test items. On average, children chose to hear from the informant that provided causal descriptions on 72% of the trials. This preference for causal information has important implications for explaining the role of conceptual information in supporting early learning and may suggest means for maximizing interest and motivation in young children.

  10. Gravity and matter in causal set theory

    International Nuclear Information System (INIS)

    Sverdlov, Roman; Bombelli, Luca

    2009-01-01

    The goal of this paper is to propose an approach to the formulation of dynamics for causal sets and coupled matter fields. We start from the continuum version of the action for a Klein-Gordon field coupled to gravity, and rewrite it first using quantities that have a direct correspondent in the case of a causal set, namely volumes, causal relations and timelike lengths, as variables to describe the geometry. In this step, the local Lagrangian density L(f;x) for a set of fields f is recast into a quasilocal expression L 0 (f;p,q) that depends on pairs of causally related points pprq and is a function of the values of f in the Alexandrov set defined by those points, and whose limit as p and q approach a common point x is L(f;x). We then describe how to discretize L 0 (f;p,q) and use it to define a causal-set-based action.

  11. A frequency domain subspace algorithm for mixed causal, anti-causal LTI systems

    NARCIS (Netherlands)

    Fraanje, Rufus; Verhaegen, Michel; Verdult, Vincent; Pintelon, Rik

    2003-01-01

    The paper extends the subspacc identification method to estimate state-space models from frequency response function (FRF) samples, proposed by McKelvey et al. (1996) for mixed causal/anti-causal systems, and shows that other frequency domain subspace algorithms can be extended similarly. The method

  12. Causal inheritance in plane wave quotients

    International Nuclear Information System (INIS)

    Hubeny, Veronika E.; Rangamani, Mukund; Ross, Simon F.

    2003-01-01

    We investigate the appearance of closed timelike curves in quotients of plane waves along spacelike isometries. First we formulate a necessary and sufficient condition for a quotient of a general spacetime to preserve stable causality. We explicitly show that the plane waves are stably causal; in passing, we observe that some pp-waves are not even distinguishing. We then consider the classification of all quotients of the maximally supersymmetric ten-dimensional plane wave under a spacelike isometry, and show that the quotient will lead to closed timelike curves iff the isometry involves a translation along the u direction. The appearance of these closed timelike curves is thus connected to the special properties of the light cones in plane wave spacetimes. We show that all other quotients preserve stable causality

  13. Inference of boundaries in causal sets

    Science.gov (United States)

    Cunningham, William J.

    2018-05-01

    We investigate the extrinsic geometry of causal sets in (1+1) -dimensional Minkowski spacetime. The properties of boundaries in an embedding space can be used not only to measure observables, but also to supplement the discrete action in the partition function via discretized Gibbons–Hawking–York boundary terms. We define several ways to represent a causal set using overlapping subsets, which then allows us to distinguish between null and non-null bounding hypersurfaces in an embedding space. We discuss algorithms to differentiate between different types of regions, consider when these distinctions are possible, and then apply the algorithms to several spacetime regions. Numerical results indicate the volumes of timelike boundaries can be measured to within 0.5% accuracy for flat boundaries and within 10% accuracy for highly curved boundaries for medium-sized causal sets with N  =  214 spacetime elements.

  14. Normalizing the causality between time series

    Science.gov (United States)

    Liang, X. San

    2015-08-01

    Recently, a rigorous yet concise formula was derived to evaluate information flow, and hence the causality in a quantitative sense, between time series. To assess the importance of a resulting causality, it needs to be normalized. The normalization is achieved through distinguishing a Lyapunov exponent-like, one-dimensional phase-space stretching rate and a noise-to-signal ratio from the rate of information flow in the balance of the marginal entropy evolution of the flow recipient. It is verified with autoregressive models and applied to a real financial analysis problem. An unusually strong one-way causality is identified from IBM (International Business Machines Corporation) to GE (General Electric Company) in their early era, revealing to us an old story, which has almost faded into oblivion, about "Seven Dwarfs" competing with a giant for the mainframe computer market.

  15. Spatial hypersurfaces in causal set cosmology

    International Nuclear Information System (INIS)

    Major, Seth A; Rideout, David; Surya, Sumati

    2006-01-01

    Within the causal set approach to quantum gravity, a discrete analogue of a spacelike region is a set of unrelated elements, or an antichain. In the continuum approximation of the theory, a moment-of-time hypersurface is well represented by an inextendible antichain. We construct a richer structure corresponding to a thickening of this antichain containing non-trivial geometric and topological information. We find that covariant observables can be associated with such thickened antichains and transitions between them, in classical sequential growth models of causal sets. This construction highlights the difference between the covariant measure on causal set cosmology and the standard sum-over-histories approach: the measure is assigned to completed histories rather than to histories on a restricted spacetime region. The resulting re-phrasing of the sum-over-histories may be fruitful in other approaches to quantum gravity

  16. Testing the causal theory of reference.

    Science.gov (United States)

    Domaneschi, Filippo; Vignolo, Massimiliano; Di Paola, Simona

    2017-04-01

    Theories of reference are a crucial research topic in analytic philosophy. Since the publication of Kripke's Naming and Necessity, most philosophers have endorsed the causal/historical theory of reference. The goal of this paper is twofold: (i) to discuss a method for testing experimentally the causal theory of reference for proper names by investigating linguistic usage and (ii) to present the results from two experiments conducted with that method. Data collected in our experiments confirm the causal theory of reference for people proper names and for geographical proper names. A secondary but interesting result is that the semantic domain affects reference assignment: while with people proper names speakers tend to assign the semantic reference, with geographical proper names they are prompted to assign the speaker's reference. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Bulk viscous cosmology with causal transport theory

    International Nuclear Information System (INIS)

    Piattella, Oliver F.; Fabris, Júlio C.; Zimdahl, Winfried

    2011-01-01

    We consider cosmological scenarios originating from a single imperfect fluid with bulk viscosity and apply Eckart's and both the full and the truncated Müller-Israel-Stewart's theories as descriptions of the non-equilibrium processes. Our principal objective is to investigate if the dynamical properties of Dark Matter and Dark Energy can be described by a single viscous fluid and how such description changes when a causal theory (Müller-Israel-Stewart's, both in its full and truncated forms) is taken into account instead of Eckart's non-causal one. To this purpose, we find numerical solutions for the gravitational potential and compare its behaviour with the corresponding ΛCDM case. Eckart's and the full causal theory seem to be disfavoured, whereas the truncated theory leads to results similar to those of the ΛCDM model for a bulk viscous speed in the interval 10 −11 || cb 2 ∼ −8

  18. Causal inheritance in plane wave quotients

    Science.gov (United States)

    Hubeny, Veronika E.; Rangamani, Mukund; Ross, Simon F.

    2004-01-01

    We investigate the appearance of closed timelike curves in quotients of plane waves along spacelike isometries. First we formulate a necessary and sufficient condition for a quotient of a general space-time to preserve stable causality. We explicitly show that the plane waves are stably causal; in passing, we observe that some pp waves are not even distinguishing. We then consider the classification of all quotients of the maximally supersymmetric ten-dimensional plane wave under a spacelike isometry, and show that the quotient will lead to closed timelike curves iff the isometry involves a translation along the u direction. The appearance of these closed timelike curves is thus connected to the special properties of the light cones in plane wave space-times. We show that all other quotients preserve stable causality.

  19. Neural correlates of continuous causal word generation.

    Science.gov (United States)

    Wende, Kim C; Straube, Benjamin; Stratmann, Mirjam; Sommer, Jens; Kircher, Tilo; Nagels, Arne

    2012-09-01

    Causality provides a natural structure for organizing our experience and language. Causal reasoning during speech production is a distinct aspect of verbal communication, whose related brain processes are yet unknown. The aim of the current study was to investigate the neural mechanisms underlying the continuous generation of cause-and-effect coherences during overt word production. During fMRI data acquisition participants performed three verbal fluency tasks on identical cue words: A novel causal verbal fluency task (CVF), requiring the production of multiple reasons to a given cue word (e.g. reasons for heat are fire, sun etc.), a semantic (free association, FA, e.g. associations with heat are sweat, shower etc.) and a phonological control task (phonological verbal fluency, PVF, e.g. rhymes with heat are meat, wheat etc.). We found that, in contrast to PVF, both CVF and FA activated a left lateralized network encompassing inferior frontal, inferior parietal and angular regions, with further bilateral activation in middle and inferior as well as superior temporal gyri and the cerebellum. For CVF contrasted against FA, we found greater bold responses only in the left middle frontal cortex. Large overlaps in the neural activations during free association and causal verbal fluency indicate that the access to causal relationships between verbal concepts is at least partly based on the semantic neural network. The selective activation in the left middle frontal cortex for causal verbal fluency suggests that distinct neural processes related to cause-and-effect-relations are associated with the recruitment of middle frontal brain areas. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. BOLD Granger causality reflects vascular anatomy.

    Directory of Open Access Journals (Sweden)

    J Taylor Webb

    Full Text Available A number of studies have tried to exploit subtle phase differences in BOLD time series to resolve the order of sequential activation of brain regions, or more generally the ability of signal in one region to predict subsequent signal in another region. More recently, such lag-based measures have been applied to investigate directed functional connectivity, although this application has been controversial. We attempted to use large publicly available datasets (FCON 1000, ADHD 200, Human Connectome Project to determine whether consistent spatial patterns of Granger Causality are observed in typical fMRI data. For BOLD datasets from 1,240 typically developing subjects ages 7-40, we measured Granger causality between time series for every pair of 7,266 spherical ROIs covering the gray matter and 264 seed ROIs at hubs of the brain's functional network architecture. Granger causality estimates were strongly reproducible for connections in a test and replication sample (n=620 subjects for each group, as well as in data from a single subject scanned repeatedly, both during resting and passive video viewing. The same effect was even stronger in high temporal resolution fMRI data from the Human Connectome Project, and was observed independently in data collected during performance of 7 task paradigms. The spatial distribution of Granger causality reflected vascular anatomy with a progression from Granger causality sources, in Circle of Willis arterial inflow distributions, to sinks, near large venous vascular structures such as dural venous sinuses and at the periphery of the brain. Attempts to resolve BOLD phase differences with Granger causality should consider the possibility of reproducible vascular confounds, a problem that is independent of the known regional variability of the hemodynamic response.

  1. Sensibilidade da rosa 'Osiana' ao etileno

    Directory of Open Access Journals (Sweden)

    Delaine Cristina Cordeiro

    2011-01-01

    Full Text Available Os objetivos deste trabalho foram determinar a sensibilidade e as respostas da rosa cultivar Osiana (Rosa × hybrida à presença de etileno ao longo da vida pós-colheita. Para determinar a sensibilidade da flor ao etileno, hastes foram cortadas e colocadas em câmaras herméticas e em seguida tratadas por 24 horas com diferentes concentrações de etileno variando de 0,0; 0,1; 1,0; 10; 100 e 1000 µL L-1do ar no interior da câmara. A rosa teve a vida pós-colheita reduzida pelo etileno, quando exposta a concentração igual ou superior a 10 µL L-1 de etileno. As flores tratadas com no mínimo de 10 µL L-1de etileno desenvolveram necrose, murcha e abscisão prematura das pétalas ainda túrgidas. As concentrações de 0,1 e 1,0 µL L-1de etileno estimularam a abertura do botão floral durante o período de 24 horas de exposição ao etileno, sem no entanto, reduzir a vida pós-colheita. A rosa 'Osiana' pode ser classificada como uma cultivar sensível ao etileno e a concentração influência os processos estimulados.

  2. Causal interpretation of stochastic differential equations

    DEFF Research Database (Denmark)

    Sokol, Alexander; Hansen, Niels Richard

    2014-01-01

    We give a causal interpretation of stochastic differential equations (SDEs) by defining the postintervention SDE resulting from an intervention in an SDE. We show that under Lipschitz conditions, the solution to the postintervention SDE is equal to a uniform limit in probability of postintervention...... structural equation models based on the Euler scheme of the original SDE, thus relating our definition to mainstream causal concepts. We prove that when the driving noise in the SDE is a Lévy process, the postintervention distribution is identifiable from the generator of the SDE....

  3. Morse theory on timelike and causal curves

    International Nuclear Information System (INIS)

    Everson, J.; Talbot, C.J.

    1976-01-01

    It is shown that the set of timelike curves in a globally hyperbolic space-time manifold can be given the structure of a Hilbert manifold under a suitable definition of 'timelike.' The causal curves are the topological closure of this manifold. The Lorentzian energy (corresponding to Milnor's energy, except that the Lorentzian inner product is used) is shown to be a Morse function for the space of causal curves. A fixed end point index theorem is obtained in which a lower bound for the index of the Hessian of the Lorentzian energy is given in terms of the sum of the orders of the conjugate points between the end points. (author)

  4. Inferring causality from noisy time series data

    DEFF Research Database (Denmark)

    Mønster, Dan; Fusaroli, Riccardo; Tylén, Kristian

    2016-01-01

    Convergent Cross-Mapping (CCM) has shown high potential to perform causal inference in the absence of models. We assess the strengths and weaknesses of the method by varying coupling strength and noise levels in coupled logistic maps. We find that CCM fails to infer accurate coupling strength...... and even causality direction in synchronized time-series and in the presence of intermediate coupling. We find that the presence of noise deterministically reduces the level of cross-mapping fidelity, while the convergence rate exhibits higher levels of robustness. Finally, we propose that controlled noise...

  5. Florística e fitossociologia de espécies arbóreas e arbustivas em uma área de Caatinga em Arcoverde, PE, Brasil

    Directory of Open Access Journals (Sweden)

    Mozart Duarte Barbosa

    2012-10-01

    Full Text Available Os estudos de florística e fitossociologia contribuem significativamente para o conhecimento das formações florestais, visto que evidenciam a riqueza e heterogeneidade dos ambientes avaliados. O trabalho foi realizado em um fragmento de Caatinga hipoxerófila no Município de Arcoverde, PE, e teve como objetivo verificar a composição florística e parâmetros fitossociológicos das espécies arbóreas e arbustivas que compõem o fragmento. O estudo foi realizado em 40 parcelas de 10 x 25 m, sendo o nível de inclusão a circunferência a 1,3 m do solo com CAP > 10 cm. Foram estimados a densidade absoluta e relativa, a frequência absoluta e relativa, a dominância absoluta e relativa e o valor de importância; a diversidade específica foi dada pelo índice de diversidade de Shannon - Weaver (H' e equabilidade de Pielou, sendo determinada a distribuição hipsométrica em intervalos de 1 m e distribuição diamétrica em intervalos com amplitude de 3 cm. No levantamento florístico das adultas, foram encontrados 1.491 indivíduos vivos, distribuídos em 36 espécies arbóreo-arbustivas, 19 famílias e 31 gêneros. As famílias que mais se destacaram foram Mimosaceae, Euphorbiaceae, Anacardiaceae, Caesalpiniaceae e Rhamnaceae. O índice de diversidade de Shannon-Weaver foi de 2,05 nats/ind. e a equabilidade de Pielou, de 0,57. Nos sete parâmetros fitossociólogicos avaliados, as espécies que mais se destacaram foram Mimosa ophthalmocentra, Poincianella pyramidalis, Senegalia bahiensis, Senegalia paniculata, Croton blanchetianus e Mimosa tenuiflora, indicando ser essas espécies as mais bem adaptadas ao ambiente avaliado, tanto nas condições edafoclimáticas quanto na competição com as demais espécies presentes no fragmento de Caatinga em Arcoverde, PE.

  6. Composición florística de pequeñas aéreas de mallines con distintas exposición y pendiente

    Directory of Open Access Journals (Sweden)

    Daniel Grima

    2015-04-01

    Full Text Available El trabajo muestra la composición florística de tres pequeñas áreas de mallines localizados en la meseta volcánica “Bella Vista” (51° 53´ S y 70° 32´ O. La misma posee una extensión aproximada de 45 km2 y presenta laderas con pendientes medias a fuertes que oscilan entre 5% y 9% (IGM 1997 y distinta exposición a la insolación y al viento. El objetivo del trabajo es caracterizar la diversidad de especies y y el estado de degradación según la aptitud forrajera (Suarez et al 2010 de los mallines en relación con la exposición y la pendiente. En gabinete se reconocieron los límites de los mallines y seleccionaron los sitios a muestrear en una imagen satelital de alta resolución espacial (IKONOS 2002. En campo se realizaron transectas perpendiculares a la pendiente y se identificaron las especies indicadoras de deterioro y de aptitud forrajera. Se estimó visualmente la cobertura vegetal y la distribución espacial de los factores de degradación.Los tres mallines exhiben composiciones florísticas y estados de degradación distintos. Carlota y Bella Vista presentan cobertura vegetal del 90 % y más diversidad florística por situarse en orientaciones menos expuestas al viento. La insolación directa favorece a Carlota en la mayor cantidad de especies relevadas (20 y 11 respectivamente, el estado de deterioro puede clasificarse de moderado a moderado severo. El mallin Gallegos Chico, con exposición oeste, recibe la acción directa del viento y su efecto abrasivo sobre las plantas afectando su porte y porcentaje de cobertura vegetal.

  7. Ocorrência da ferrugem da videira em Minas Gerais

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    Adelica Aparecida Xavier

    2012-03-01

    Full Text Available A ferrugem da videira causada por Phakopsora euvitis Ono constitui-se numa ameaça às regiões produtoras de uva em função do potencial destrutivo da planta. A doença foi detectada no Brasil, pela primeira vez, em 2001. Atualmente, ela ocorre no Paraná, Mato Grosso do Sul, São Paulo, Rio Grande do Sul, Mato Grosso, Roraima, Espírito Santo e Santa Catarina. Em abril de 2010, observaram-se na estação experimental da Unimontes, Janaúba, Minas Gerais, plantas da cv. Niágara rosada com sintomas típicos da doença. A análise dos sintomas e a caracterização dos urediniósporos sésseis, levemente equinulados, com formato oval, ou elipsoide formado em urédias subepidérmicas na origem, inrompentes e com paráfises circundantes dorsalmente, levaram à diagnose de Phakopsora euvitis como o agente causal da doença. Este é o primeiro relato da doença no Estado de Minas Gerais.

  8. Efeito do cozimento sobre alguns fatores antinutricionais em folhas de brócoli, couve- flor e couve Effect of boiling on contents of antinutritional factors in leaves of broccoli, cauliflower and cabbage

    Directory of Open Access Journals (Sweden)

    Mônica Alessandra Teixeira dos Santos

    2006-04-01

    Full Text Available Os resíduos vegetais desprezados pela indústria e durante o preparo dos alimentos poderiam ser utilizados como fontes alternativas de nutrientes contribuindo para o enriquecimento da dieta das populações carentes. Por outro lado, muitos alimentos vegetais são fontes de fatores antinutricionais que interferem na digestão ou absorção de nutrientes. Determinou-se os teores de polifenóis, nitrato e ácido oxálico de folhas de brócoli, couve-flor e couve submetidas à cocção por seis diferentes tempos (0, 2, 4, 6, 8 e 10 minutos. Verificou-se queda nos teores de fatores antinutricionais com o aumento do tempo de cozimento, mostrando-se aceitáveis para o consumo. No entanto, os tratamentos utilizados não foram suficientes para reduzir os teores de polifenóis das folhas de brócoli e couve a valores considerados adequados ao consumo humano, sugerindo a utilização conjunta de outra metodologia para a redução dos polifenóis presentes nesses vegetais.The vegetable residues despised from the industry and during the food preparation might be used as an alternative nutrient source that provides poor people a richer diet. Otherwise, many vegetables are source of antinutritional factors that might influence in the digest or in the nutrients absorption. As the purpose to determining the contents of poliphenols, oxalic acid and nitrate in leaves of broccoli, cauliflower and cabbage, they were submitted to cooking in six different times (0, 2, 4, 6, 8 and 10 minutes. The results showed that the antinutritional factors dropped with the increase of the cooking time, being acceptable for the consumption. However, the treatments were not enought to decrease the contents of poliphenols in leaves of broccoli and cabbage considering values to the human consumption. Thus, it had better to use another methodology to decrease the level of polyphenols in the vegetables.

  9. Causal Meta-Analysis : Methodology and Applications

    NARCIS (Netherlands)

    Bax, L.J.

    2009-01-01

    Meta-analysis is a statistical method to summarize research data from multiple studies in a quantitative manner. This dissertation addresses a number of methodological topics in causal meta-analysis and reports the development and validation of meta-analysis software. In the first (methodological)

  10. Information-causality and extremal tripartite correlations

    International Nuclear Information System (INIS)

    Yang, Tzyh Haur; Cavalcanti, Daniel; Almeida, Mafalda L; Teo, Colin; Scarani, Valerio

    2012-01-01

    We study the principle of information-causality (IC) in the presence of extremal no-signaling correlations on a tripartite scenario. We prove that all, except one, of the non-local correlations lead to violation of IC. The remaining non-quantum correlation is shown to satisfy any bipartite physical principle. (paper)

  11. The causal structure of utility conditionals.

    Science.gov (United States)

    Bonnefon, Jean-François; Sloman, Steven A

    2013-01-01

    The psychology of reasoning is increasingly considering agents' values and preferences, achieving greater integration with judgment and decision making, social cognition, and moral reasoning. Some of this research investigates utility conditionals, ''if p then q'' statements where the realization of p or q or both is valued by some agents. Various approaches to utility conditionals share the assumption that reasoners make inferences from utility conditionals based on the comparison between the utility of p and the expected utility of q. This article introduces a new parameter in this analysis, the underlying causal structure of the conditional. Four experiments showed that causal structure moderated utility-informed conditional reasoning. These inferences were strongly invited when the underlying structure of the conditional was causal, and significantly less so when the underlying structure of the conditional was diagnostic. This asymmetry was only observed for conditionals in which the utility of q was clear, and disappeared when the utility of q was unclear. Thus, an adequate account of utility-informed inferences conditional reasoning requires three components: utility, probability, and causal structure. Copyright © 2012 Cognitive Science Society, Inc.

  12. Comments: Causal Interpretations of Mediation Effects

    Science.gov (United States)

    Jo, Booil; Stuart, Elizabeth A.

    2012-01-01

    The authors thank Dr. Lindsay Page for providing a nice illustration of the use of the principal stratification framework to define causal effects, and a Bayesian model for effect estimation. They hope that her well-written article will help expose education researchers to these concepts and methods, and move the field of mediation analysis in…

  13. Inductive reasoning about causally transmitted properties.

    Science.gov (United States)

    Shafto, Patrick; Kemp, Charles; Bonawitz, Elizabeth Baraff; Coley, John D; Tenenbaum, Joshua B

    2008-11-01

    Different intuitive theories constrain and guide inferences in different contexts. Formalizing simple intuitive theories as probabilistic processes operating over structured representations, we present a new computational model of category-based induction about causally transmitted properties. A first experiment demonstrates undergraduates' context-sensitive use of taxonomic and food web knowledge to guide reasoning about causal transmission and shows good qualitative agreement between model predictions and human inferences. A second experiment demonstrates strong quantitative and qualitative fits to inferences about a more complex artificial food web. A third experiment investigates human reasoning about complex novel food webs where species have known taxonomic relations. Results demonstrate a double-dissociation between the predictions of our causal model and a related taxonomic model [Kemp, C., & Tenenbaum, J. B. (2003). Learning domain structures. In Proceedings of the 25th annual conference of the cognitive science society]: the causal model predicts human inferences about diseases but not genes, while the taxonomic model predicts human inferences about genes but not diseases. We contrast our framework with previous models of category-based induction and previous formal instantiations of intuitive theories, and outline challenges in developing a complete model of context-sensitive reasoning.

  14. Exploring Causal Models of Educational Achievement.

    Science.gov (United States)

    Parkerson, Jo Ann; And Others

    1984-01-01

    This article evaluates five causal model of educational productivity applied to learning science in a sample of 882 fifth through eighth graders. Each model explores the relationship between achievement and a combination of eight constructs: home environment, peer group, media, ability, social environment, time on task, motivation, and…

  15. Sequential causal learning in humans and rats

    NARCIS (Netherlands)

    Lu, H.; Rojas, R.R.; Beckers, T.; Yuille, A.; Love, B.C.; McRae, K.; Sloutsky, V.M.

    2008-01-01

    Recent experiments (Beckers, De Houwer, Pineño, & Miller, 2005;Beckers, Miller, De Houwer, & Urushihara, 2006) have shown that pretraining with unrelated cues can dramatically influence the performance of humans in a causal learning paradigm and rats in a standard Pavlovian conditioning paradigm.

  16. The Causal Foundations of Structural Equation Modeling

    Science.gov (United States)

    2012-02-16

    and Baumrind (1993).” This, together with the steady influx of statisticians into the field, has left SEM re- searchers in a quandary about the...considerations. Journal of Personality and Social Psychology 51 1173–1182. Baumrind , D. (1993). Specious causal attributions in social sciences: The

  17. Causal Measurement Models: Can Criticism Stimulate Clarification?

    Science.gov (United States)

    Markus, Keith A.

    2016-01-01

    In their 2016 work, Aguirre-Urreta et al. provided a contribution to the literature on causal measurement models that enhances clarity and stimulates further thinking. Aguirre-Urreta et al. presented a form of statistical identity involving mapping onto the portion of the parameter space involving the nomological net, relationships between the…

  18. A quantum probability model of causal reasoning

    Directory of Open Access Journals (Sweden)

    Jennifer S Trueblood

    2012-05-01

    Full Text Available People can often outperform statistical methods and machine learning algorithms in situations that involve making inferences about the relationship between causes and effects. While people are remarkably good at causal reasoning in many situations, there are several instances where they deviate from expected responses. This paper examines three situations where judgments related to causal inference problems produce unexpected results and describes a quantum inference model based on the axiomatic principles of quantum probability theory that can explain these effects. Two of the three phenomena arise from the comparison of predictive judgments (i.e., the conditional probability of an effect given a cause with diagnostic judgments (i.e., the conditional probability of a cause given an effect. The third phenomenon is a new finding examining order effects in predictive causal judgments. The quantum inference model uses the notion of incompatibility among different causes to account for all three phenomena. Psychologically, the model assumes that individuals adopt different points of view when thinking about different causes. The model provides good fits to the data and offers a coherent account for all three causal reasoning effects thus proving to be a viable new candidate for modeling human judgment.

  19. A Causal Model of Faculty Turnover Intentions.

    Science.gov (United States)

    Smart, John C.

    1990-01-01

    A causal model assesses the relative influence of individual attributes, institutional characteristics, contextual-work environment variables, and multiple measures of job satisfaction on faculty intentions to leave their current institutions. Factors considered include tenure status, age, institutional status, governance style, organizational…

  20. Catastrophizing and Causal Beliefs in Whiplash

    NARCIS (Netherlands)

    Buitenhuis, J.; de Jong, P. J.; Jaspers, J. P. C.; Groothoff, J. W.

    2008-01-01

    Study Design. Prospective cohort study. Objective. This study investigates the role of pain catastrophizing and causal beliefs with regard to severity and persistence of neck complaints after motor vehicle accidents. Summary of Background Data. In previous research on low back pain, somatoform

  1. Probable autoimmune causal relationship between periodontitis and ...

    African Journals Online (AJOL)

    Periodontitis is a multifactorial disease with microbial dental plaque as the initiator of periodontal disease. However, the manifestation and progression of the disease is influenced by a wide variety of determinants and factors. The strongest type of causal relationship is the association of systemic and periodontal disease.

  2. On minimizers of causal variational principles

    International Nuclear Information System (INIS)

    Schiefeneder, Daniela

    2011-01-01

    Causal variational principles are a class of nonlinear minimization problems which arise in a formulation of relativistic quantum theory referred to as the fermionic projector approach. This thesis is devoted to a numerical and analytic study of the minimizers of a general class of causal variational principles. We begin with a numerical investigation of variational principles for the fermionic projector in discrete space-time. It is shown that for sufficiently many space-time points, the minimizing fermionic projector induces non-trivial causal relations on the space-time points. We then generalize the setting by introducing a class of causal variational principles for measures on a compact manifold. In our main result we prove under general assumptions that the support of a minimizing measure is either completely timelike, or it is singular in the sense that its interior is empty. In the examples of the circle, the sphere and certain flag manifolds, the general results are supplemented by a more detailed analysis of the minimizers. (orig.)

  3. Causality and analyticity in quantum fields theory

    International Nuclear Information System (INIS)

    Iagolnitzer, D.

    1992-01-01

    This is a presentation of results on the causal and analytical structure of Green functions and on the collision amplitudes in fields theories, for massive particles of one type, with a positive mass and a zero spin value. (A.B.)

  4. Causality and Time in Historical Institutionalism

    DEFF Research Database (Denmark)

    Mahoney, James; Mohamedali, Khairunnisa; Nguyen, Christoph

    2016-01-01

    This chapter explores the dual concern with causality and time in historical institutionalism using a graphical approach. The analysis focuses on three concepts that are central to this field: critical junctures, gradual change, and path dependence. The analysis makes explicit and formal the logi...

  5. Inductive Reasoning about Causally Transmitted Properties

    Science.gov (United States)

    Shafto, Patrick; Kemp, Charles; Bonawitz, Elizabeth Baraff; Coley, John D.; Tenenbaum, Joshua B.

    2008-01-01

    Different intuitive theories constrain and guide inferences in different contexts. Formalizing simple intuitive theories as probabilistic processes operating over structured representations, we present a new computational model of category-based induction about causally transmitted properties. A first experiment demonstrates undergraduates'…

  6. Black Hole Complementarity and Violation of Causality

    OpenAIRE

    Rozenblit, Moshe

    2017-01-01

    Analysis of a massive shell collapsing on a solid sphere shows that black hole complementarity (BHC) violates causality in its effort to save information conservation. In particular, this note describes a hypothetical contraption based on BHC that would allow the transfer of information from the future to the present.

  7. Encoding dependence in Bayesian causal networks

    Science.gov (United States)

    Bayesian networks (BNs) represent complex, uncertain spatio-temporal dynamics by propagation of conditional probabilities between identifiable states with a testable causal interaction model. Typically, they assume random variables are discrete in time and space with a static network structure that ...

  8. Causality in the semantics of Esterel : revisited

    NARCIS (Netherlands)

    Mousavi, M.R.; Klin, B.; Sobocinski, P.

    2010-01-01

    We re-examine the challenges concerning causality in the semantics of Esterel and show that they pertain to the known issues in the semantics of Structured Operational Semantics with negative premises. We show that the solutions offered for the semantics of SOS also provide answers to the semantic

  9. Scalar field Green functions on causal sets

    International Nuclear Information System (INIS)

    Nomaan Ahmed, S; Surya, Sumati; Dowker, Fay

    2017-01-01

    We examine the validity and scope of Johnston’s models for scalar field retarded Green functions on causal sets in 2 and 4 dimensions. As in the continuum, the massive Green function can be obtained from the massless one, and hence the key task in causal set theory is to first identify the massless Green function. We propose that the 2d model provides a Green function for the massive scalar field on causal sets approximated by any topologically trivial 2-dimensional spacetime. We explicitly demonstrate that this is indeed the case in a Riemann normal neighbourhood. In 4d the model can again be used to provide a Green function for the massive scalar field in a Riemann normal neighbourhood which we compare to Bunch and Parker’s continuum Green function. We find that the same prescription can also be used for de Sitter spacetime and the conformally flat patch of anti-de Sitter spacetime. Our analysis then allows us to suggest a generalisation of Johnston’s model for the Green function for a causal set approximated by 3-dimensional flat spacetime. (paper)

  10. Are bruxism and the bite causally related?

    NARCIS (Netherlands)

    Lobbezoo, F.; Ahlberg, J.; Manfredini, D.; Winocur, E.

    2012-01-01

    In the dental profession, the belief that bruxism and dental (mal-)occlusion (‘the bite’) are causally related is widespread. The aim of this review was to critically assess the available literature on this topic. A PubMed search of the English-language literature, using the query ‘Bruxism [Majr

  11. Causality relationship between energy demand and economic ...

    African Journals Online (AJOL)

    This paper attempts to examine the causal relationship between electricity demand and economic growth in Nigeria using data for 1970 – 2003. The study uses the Johansen cointegration VAR approach. The ADF and Phillips – Perron test statistics were used to test for stationarity of the data. It was found that the data were ...

  12. Composição, diversidade e similaridade florística de uma floresta tropical semidecídua submontana em Marcelândia - MT Floristic composition, diversity and similarity of a submontane semideciduous tropical forest in Marcelândia - MT

    Directory of Open Access Journals (Sweden)

    Elbert Viana Ferreira Júnior

    2008-12-01

    Full Text Available O objetivo deste estudo foi avaliar a composição, diversidade e similaridade florística de uma área de floresta estacional semidecidual localizada no município de Marcelândia-MT, em área de tensão ecológica, na região de contato floresta ombrófila/floresta estacional. Foram amostrados 4008 indivíduos, pertencentes a 33 famílias e 92 espécies, em 74 parcelas de 10 m x 250 m. As famílias que apresentaram maior valor percentual de árvores foram: Lauraceae (15,99%, Melastomataceae (12,97%, Sapotaceae (12,50%, Fabaceae - Mimosoideae (9,91%, Burseraceae (9,13% e Moraceae (7,29%. Os valores obtidos para os índices de diversidade Shannon-Weaver, de concentração de Simpson e de equitabilidade de Pielou indicaram que a área apresenta diversidade relativamente alta e baixa concentração de espécies com alta uniformidade nas proporções indivíduos/espécies dentro da comunidade vegetal. Os padrões de similaridade florística evidenciaram baixa similaridade entre as áreas avaliadas evidenciando existência de padrões fitogeográficos baseados na distribuição das espécies.The objective of this study was to analyze the floristic composition, diversity and similarity of a submontane, semideciduous tropical forest in Marcelândia-MT, in an ecological tension area in the forest contact region. The 33 families and 92 species specimens were found in 4008 individuals, in 74 plots of 10m x 250 m. The families that contributed most frequently to the floristic composition were Lauraceae (15.99%, Melastomataceae (12.97%, Sapotaceae (12.50%, Fabaceae - Mimosoideae (9.91%, Burseraceae (9.13% and Moraceae (7.29%. The Shannon-Weaver diversity, Simpson concentration and Pielou evenness indexes indicated that the area presents relatively high diversity and low concentration of species with high uniformity in the ratios of individuals per species. The floristic similarity standards had low similarity among the evaluated areas evidencing the

  13. Canales de distribución y estrategias de comercialización para la flor colombiana en los Estados Unidos: un marco conceptual

    Directory of Open Access Journals (Sweden)

    LUIS FELIPE SALOM SERNA

    2012-01-01

    Full Text Available El floricultor colombiano no puede desconocer los cambios en tendencias de consumo ni la consolidación del canal retail en su mercado principal, USA. El cuál generará un alto impacto en las características del negocio y el papel de los jugadores en la cadena de suministros. El objetivo de este estudio exploratorio utilizando casos múltiples, es presentar un marco de oportunidades para fortalecer la comercialización de la flor y estructurar canales de distribución acordes a las necesidades del consumidor norteamericano y a los cambios en los hábitos de compra. Las conclusiones, proponen las acciones a emprender por las empresas floricultoras estudiadas a fin de incrementar su competitividad y resolver su dilema actual: contraer oferta para mejorar el precio de venta o incrementar demanda.

  14. Canales de distribución y estrategias de comercialización para la flor colombiana en los Estados Unidos: un marco conceptual

    Directory of Open Access Journals (Sweden)

    Luis Felipe Salom Serna

    2012-07-01

    Full Text Available El floricultor colombiano no puede desconocer los cambios en tendencias de consumo ni la consolidación del canal retail en su mercado principal, usa.El cuál generará un alto impacto en las características del negocio y el papel de los jugadores en la cadena de suministros. El objetivo de este estudio exploratorio utilizando casos múltiples, es presentar un marco de oportunidades para fortalecer la comercialización de la flor y estructurar canales de distribución acordes a las necesidades del consumidor norteamericano y a los cambios en los hábitos de compra. Las conclusiones, proponen las acciones a emprender por las empresas floriculturas estudiadas a fin de incrementar su competitividad y resolver su dilema actual: contraer oferta para mejorar el precio de venta o incrementar demanda.

  15. La descentralización a la luz del caso Bella Flor en Ciudad Bolívar, Bogotá

    Directory of Open Access Journals (Sweden)

    Pening G Jean Philippe

    2005-12-01

    Full Text Available En Colombia, las políticas de descentralización se profundizaron con la Constitución Política de 1991 y los desarrollos legislativos posteriores. A los municipios se les devolvió la responsabilidad en inversiones en sectores como educación, salud y agua potable y saneamiento básico. Bogotá presenta los mejores indicadores colombianos, sin embargo en la ciudad conviven hogares que presentan indicadores bastante alejados del promedio de la localidad, de la ciudad y del país. Para demostrarlo, se realizó un censo en el barrio Bella Flor de la localidad de Ciudad Bolívar en Bogotá, el cual arroja unos resultados que comparamos con un censo realizado en 2000 y con resultados de encuestas del DANE.

  16. Análise florística e estrutural de sistemas silviagrícolas em Tomé-Açu, Pará.

    OpenAIRE

    BOLFE, E. L.; BATISTELLA, M.

    2012-01-01

    O objetivo deste trabalho foi analisar a composição florística e estrutural de sistemas silviagrícolas em Tomé-Açu, Pará. Os dados dendrométricos foram obtidos por inventário em 40 parcelas amostrais, com três unidades cada uma, no total de 120 unidades de 10x10 m. Foi inventariada a média de 1.424,3 indivíduos por hectare, pertencentes a 27 famílias e a 54 espécies. Tendo-se considerado a variabilidade dos estágios vegetativos, os diferentes sistemas silviagrícolas (SAF) foram divididos em q...

  17. Composição, diversidade e similaridade florística de uma floresta tropical semidecídua submontana em Marcelândia - MT

    OpenAIRE

    Ferreira Júnior,Elbert Viana; Soares,Thelma Shirlen; Costa,Marcus Filipe Fernandes da; Moraes e Silva,Versides Sebastião

    2008-01-01

    O objetivo deste estudo foi avaliar a composição, diversidade e similaridade florística de uma área de floresta estacional semidecidual localizada no município de Marcelândia-MT, em área de tensão ecológica, na região de contato floresta ombrófila/floresta estacional. Foram amostrados 4008 indivíduos, pertencentes a 33 famílias e 92 espécies, em 74 parcelas de 10 m x 250 m. As famílias que apresentaram maior valor percentual de árvores foram: Lauraceae (15,99%), Melastomataceae (12,97%), Sapo...

  18. Estructura y composición florística de tres robledales en la región norte de la cordillera central de Colombia

    Directory of Open Access Journals (Sweden)

    Juan D León

    2009-12-01

    Full Text Available La alta diversidad florística que albergan los ecosistemas andinos está siendo amenazada por fuertes presiones de origen antrópico. Uno de estos ecosistemas son los robledales, bosques dominados por la especie Quercus humboldtii, que se encuentra seriamente amenazada en Colombia porque su madera es valiosa comercial y dendroenergéticamente. En este estudio, se caracterizó la composición florística y la estructura de tres robledales de los Andes colombianos, con el fin de determinar su similaridad. En cada sitio, se estableció una parcela permanente (5 000 m² donde se muestrearon todos los árboles con D ≥ 10 cm. En los tres sitios, la especie dominante fue Q. humboldtii, pero la similitud florística entre ellos no fue alta. La estructura por clases de tamaño para los tres sitios fue en forma de J invertida, aunque varió la abundancia de individuos por clase diamétrica. Los resultados indican que los robledales estudiados difieren en su composición florística y estructura a pesar de presentar características biofísicas similares. Las diferencias encontradas se deben posiblemente, a los diferentes factores que interactúan en cada sitio como la historia de uso, intensidad y duración de las perturbaciones antrópicas pasadas, topografía, fauna y clima local, que se ven reflejados en los parámetros estructurales de la vegetación.Structure and floristic composition of three oak forests in the northern region of the Central Cordillera in Colombia. Andean ecosystems harbor a high floristic diversity, which is being threatened by human disturbances such us deforestation and by the expansion of the agricultural frontier. One of these ecosystems are the Andean oak forests dominated by Quercus humboldtii, a threatened species in Colombia. We assessed the floristic composition and structure of three Andean oak forests located in three localities (San Andrés de Cuerquia, Belmira and Guarne of Antioquia. The main goal was to determine

  19. La organización de eventos como estrategia identitaria y evocadora de imagen turística. Estudio de caso: Girona Temps de Flors

    Directory of Open Access Journals (Sweden)

    Jiménez Morales, Mònika

    2009-01-01

    Full Text Available For the last 53 years the city of Girona organizes a massive event based on the floral art which, in its last occasions, has mobilized more than half million of visitors, many of them from all parts of Europe. Besides the flowers, the photography exhibitions or the audio-visual montages which, during the second week of May, fill the streets of the ancient part of the city, the fact is that Girona Temps de Flors represents an important communicative strategy for the territory promotion. In effect, the event, by itself, develops varied functions in the emotional area of the lived space, but there’s more. It can also become a catalyst of images, the creator of images capable of establishing a brand name of a city. The present article will show the possibilities that flow from the organisation of an event relative to the positioning of the identity and promotion of a territory.

  20. Levantamento florístico no cerrado de Pedregulho, SP, Brasil Floristic inventory of cerrado at Pedregulho, São Paulo State, Brazil

    Directory of Open Access Journals (Sweden)

    Denise Sasaki

    2008-03-01

    Full Text Available Em Pedregulho, município do extremo nordeste do Estado de São Paulo, ocorrem fragmentos de cerrado considerados floristicamente distintos dos demais remanescentes paulistas. Nesse estudo, foi realizado um levantamento florístico em Pedregulho, abordando duas regiões geologicamente distintas: o Parque Estadual das Furnas do Bom Jesus e o distrito de Estreito. Em cada uma, delimitaram-se duas parcelas de 50×50 m, totalizando um hectare, onde foram encontradas 65 famílias e 379 espécies de angiospermas. Coletas em áreas adjacentes totalizaram 71 famílias e 443 espécies. As duas regiões estudadas têm baixa similaridade florística entre si. A distribuição geográfica das espécies é analisada e oito padrões são delimitados para aquelas cuja distribuição no Estado de São Paulo é restrita à região de Pedregulho.Pedregulho municipality in the far northeastern region of São Paulo state has fragments of cerrado vegetation thought to be floristically distinct from other cerrado remmants in the state. In this study, a floristic survey was carried out at Pedregulho, focusing on two geologically distinct regions: Furnas do Bom Jesus State Park and the Estreito district. In each region, 50×50 m plots were set up for a total sample area of 1 hectare, where 65 families and 379 angiosperm species were recorded. Collecting efforts in adjacent areas resulted in a total of 71 families and 443 species. The two study areas had low floristic similarity. Geographic species distribution was analyzed and eight patterns were defined for those species restricted to the Pedregulho region in São Paulo.

  1. ASSESSMENT OF THE QUALITY OF THE WATER OF FOUR JAGÜEYES IN THE STATE PARK “FLOR DEL BOSQUE”, PUEBLA, MEXICO

    Directory of Open Access Journals (Sweden)

    Gabriela Pérez-Osorio

    2016-01-01

    Full Text Available The water supply is currently a problem, given the over-exploitation of groundwater and contamination of surface water, so it is important to find alternative supplies. The rain water harvesting is considered one of the most viable options for the supply of the vital liquid; some of the most utilized systems for this purpose are the jagüeyes. State Park General Lázaro Cárdenas del Río better known as "Flor del Bosque", it is located east of the city of Puebla and listed as Protected Natural Area, this park has jagüeyes which store water from rain. In this research, the main physicochemical and microbiological parameters of water stored in four jagüeyes of “Flor del Bosque” were measured according to Mexican regulations, in order to establish its quality and determine the uses that are given as a watering wooded areas and drinking trough do not represent a risk to the flora and fauna of the park. Composite samples of each jagüey were analyzed, during two dry weather stations and two rainy weather stations between the moths of November 2011 and October 2012. The water of the four jagüeyes has microbiological contamination by helminth eggs, Fasciola hepatica, fecal (180 CFU and total coliforms (475 CFU, this represents a risk to the health of wildlife; as well as lots of settleable and suspended solids. Since these systems have been installed for watering wooded areas and drinking trough of animals live there, it would be advisable before use be given appropriate treatment, plus it aims to improve its design or construction to be suitable for the intended uses.

  2. Does Causality Matter More Now? Increase in the Proportion of Causal Language in English Texts.

    Science.gov (United States)

    Iliev, Rumen; Axelrod, Robert

    2016-05-01

    The vast majority of the work on culture and cognition has focused on cross-cultural comparisons, largely ignoring the dynamic aspects of culture. In this article, we provide a diachronic analysis of causal cognition over time. We hypothesized that the increased role of education, science, and technology in Western societies should be accompanied by greater attention to causal connections. To test this hypothesis, we compared word frequencies in English texts from different time periods and found an increase in the use of causal language of about 40% over the past two centuries. The observed increase was not attributable to general language effects or to changing semantics of causal words. We also found that there was a consistent difference between the 19th and the 20th centuries, and that the increase happened mainly in the 20th century. © The Author(s) 2016.

  3. Causal knowledge and the development of inductive reasoning.

    Science.gov (United States)

    Bright, Aimée K; Feeney, Aidan

    2014-06-01

    We explored the development of sensitivity to causal relations in children's inductive reasoning. Children (5-, 8-, and 12-year-olds) and adults were given trials in which they decided whether a property known to be possessed by members of one category was also possessed by members of (a) a taxonomically related category or (b) a causally related category. The direction of the causal link was either predictive (prey→predator) or diagnostic (predator→prey), and the property that participants reasoned about established either a taxonomic or causal context. There was a causal asymmetry effect across all age groups, with more causal choices when the causal link was predictive than when it was diagnostic. Furthermore, context-sensitive causal reasoning showed a curvilinear development, with causal choices being most frequent for 8-year-olds regardless of context. Causal inductions decreased thereafter because 12-year-olds and adults made more taxonomic choices when reasoning in the taxonomic context. These findings suggest that simple causal relations may often be the default knowledge structure in young children's inductive reasoning, that sensitivity to causal direction is present early on, and that children over-generalize their causal knowledge when reasoning. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. The causal link between energy and output growth: Evidence from Markov switching Granger causality

    International Nuclear Information System (INIS)

    Kandemir Kocaaslan, Ozge

    2013-01-01

    In this paper we empirically investigate the causal link between energy consumption and economic growth employing a Markov switching Granger causality analysis. We carry out our investigation using annual U.S. real GDP, total final energy consumption and total primary energy consumption data which cover the period between 1968 and 2010. We find that there are significant changes in the causal relation between energy consumption and economic growth over the sample period under investigation. Our results show that total final energy consumption and total primary energy consumption have significant predictive content for real economic activity in the U.S. economy. Furthermore, the causality running from energy consumption to output growth seems to be strongly apparent particularly during the periods of economic downturn and energy crisis. We also document that output growth has predictive power in explaining total energy consumption. Furthermore, the power of output growth in predicting total energy consumption is found to diminish after the mid of 1980s. - Highlights: • Total energy consumption has predictive content for real economic activity. • The causality from energy to output growth is apparent in the periods of recession. • The causality from energy to output growth is strong in the periods of energy crisis. • Output growth has predictive power in explaining total energy consumption. • The power of output growth in explaining energy diminishes after the mid of 1980s

  5. Elements of Causal Inference: Foundations and Learning Algorithms

    DEFF Research Database (Denmark)

    Peters, Jonas Martin; Janzing, Dominik; Schölkopf, Bernhard

    A concise and self-contained introduction to causal inference, increasingly important in data science and machine learning......A concise and self-contained introduction to causal inference, increasingly important in data science and machine learning...

  6. The causal relationship between Foreign Direct Investment (FDI ...

    African Journals Online (AJOL)

    The causal relationship between Foreign Direct Investment (FDI) and the ... of selected west African countries: Panel ARDL/Granger Causality Analysis. ... among this developing countries and an important revelation for policy implication.

  7. The Hankel transform of causal distributions

    Directory of Open Access Journals (Sweden)

    Manuel A. Aguirre T.

    2012-03-01

    Full Text Available In this note we evaluate the unidimensional distributional Hankel transform of \\dfrac{x^{\\alpha-1}_{+}}{\\Gamma^{\\alpha}},\\dfrac{x^{\\alpha-1}_{-}}{\\Gamma^{\\alpha}},dfrac{|x|^{\\alpha-1}}{\\Gamma^{\\frac{\\alpha}{2}}},dfrac{|x|^{\\alpha-1}sgn(x}{\\Gamma^{\\frac{\\alpha +1}{2}}} and (x± i0^{\\alpha-1} and then we extend the formulae to certain kinds of n-dimensional distributions calles "causal" and "anti-causal" distributions. We evaluate the distributional Handel transform of \\dfrac{(m^2+P^{\\alpha -1}_{-}}{\\Gamma^{(\\alpha} }, \\dfrac{|m^2+P|^{\\alpha -1}_{-}}{\\Gamma^{(\\frac{\\alpha}{2}}}, \\dfrac{|m^2+P|^{\\alpha -1}sgn(m^2+P}{\\Gamma (\\frac{\\alpha +1}{2 }} and (m^2+P±i0^{\\alpha-1}

  8. A new spin on causality constraints

    Energy Technology Data Exchange (ETDEWEB)

    Hartman, Thomas; Jain, Sachin; Kundu, Sandipan [Department of Physics, Cornell University, Ithaca, New York (United States)

    2016-10-26

    Causality in a shockwave state is related to the analytic properties of a four-point correlation function. Extending recent results for scalar probes, we show that this constrains the couplings of the stress tensor to light spinning operators in conformal field theory, and interpret these constraints in terms of the interaction with null energy. For spin-1 and spin-2 conserved currents in four dimensions, the resulting inequalities are a subset of the Hofman-Maldacena conditions for positive energy deposition. It is well known that energy conditions in holographic theories are related to causality on the gravity side; our results make a connection on the CFT side, and extend it to non-holographic theories.

  9. Reciprocity, passivity and causality in Willis materials.

    Science.gov (United States)

    Muhlestein, Michael B; Sieck, Caleb F; Alù, Andrea; Haberman, Michael R

    2016-10-01

    Materials that require coupling between the stress-strain and momentum-velocity constitutive relations were first proposed by Willis (Willis 1981 Wave Motion 3 , 1-11. (doi:10.1016/0165-2125(81)90008-1)) and are now known as elastic materials of the Willis type, or simply Willis materials. As coupling between these two constitutive equations is a generalization of standard elastodynamic theory, restrictions on the physically admissible material properties for Willis materials should be similarly generalized. This paper derives restrictions imposed on the material properties of Willis materials when they are assumed to be reciprocal, passive and causal. Considerations of causality and low-order dispersion suggest an alternative formulation of the standard Willis equations. The alternative formulation provides improved insight into the subwavelength physical behaviour leading to Willis material properties and is amenable to time-domain analyses. Finally, the results initially obtained for a generally elastic material are specialized to the acoustic limit.

  10. Granger-Causality Maps of Diffusion Processes

    Czech Academy of Sciences Publication Activity Database

    Wahl, B.; Feudel, U.; Hlinka, Jaroslav; Wächter, M.; Peinke, J.; Freund, J.A.

    2016-01-01

    Roč. 93, č. 2 16 February (2016), č. článku 022213. ISSN 2470-0045 R&D Projects: GA ČR GA13-23940S; GA MZd(CZ) NV15-29835A Institutional support: RVO:67985807 Keywords : Granger causality * stochastic process * diffusion process * nonlinear dynamical systems Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 2.366, year: 2016

  11. Curvature constraints from the causal entropic principle

    International Nuclear Information System (INIS)

    Bozek, Brandon; Albrecht, Andreas; Phillips, Daniel

    2009-01-01

    Current cosmological observations indicate a preference for a cosmological constant that is drastically smaller than what can be explained by conventional particle physics. The causal entropic principle (Bousso et al.) provides an alternative approach to anthropic attempts to predict our observed value of the cosmological constant by calculating the entropy created within a causal diamond. We have extended this work to use the causal entropic principle to predict the preferred curvature within the 'multiverse'. We have found that values larger than ρ k =40ρ m are disfavored by more than 99.99% peak value at ρ Λ =7.9x10 -123 and ρ k =4.3ρ m for open universes. For universes that allow only positive curvature or both positive and negative curvature, we find a correlation between curvature and dark energy that leads to an extended region of preferred values. Our universe is found to be disfavored to an extent depending on the priors on curvature. We also provide a comparison to previous anthropic constraints on open universes and discuss future directions for this work.

  12. Structure induction in diagnostic causal reasoning.

    Science.gov (United States)

    Meder, Björn; Mayrhofer, Ralf; Waldmann, Michael R

    2014-07-01

    Our research examines the normative and descriptive adequacy of alternative computational models of diagnostic reasoning from single effects to single causes. Many theories of diagnostic reasoning are based on the normative assumption that inferences from an effect to its cause should reflect solely the empirically observed conditional probability of cause given effect. We argue against this assumption, as it neglects alternative causal structures that may have generated the sample data. Our structure induction model of diagnostic reasoning takes into account the uncertainty regarding the underlying causal structure. A key prediction of the model is that diagnostic judgments should not only reflect the empirical probability of cause given effect but should also depend on the reasoner's beliefs about the existence and strength of the link between cause and effect. We confirmed this prediction in 2 studies and showed that our theory better accounts for human judgments than alternative theories of diagnostic reasoning. Overall, our findings support the view that in diagnostic reasoning people go "beyond the information given" and use the available data to make inferences on the (unobserved) causal rather than on the (observed) data level. (c) 2014 APA, all rights reserved.

  13. Causal inference of asynchronous audiovisual speech

    Directory of Open Access Journals (Sweden)

    John F Magnotti

    2013-11-01

    Full Text Available During speech perception, humans integrate auditory information from the voice with visual information from the face. This multisensory integration increases perceptual precision, but only if the two cues come from the same talker; this requirement has been largely ignored by current models of speech perception. We describe a generative model of multisensory speech perception that includes this critical step of determining the likelihood that the voice and face information have a common cause. A key feature of the model is that it is based on a principled analysis of how an observer should solve this causal inference problem using the asynchrony between two cues and the reliability of the cues. This allows the model to make predictions abut the behavior of subjects performing a synchrony judgment task, predictive power that does not exist in other approaches, such as post hoc fitting of Gaussian curves to behavioral data. We tested the model predictions against the performance of 37 subjects performing a synchrony judgment task viewing audiovisual speech under a variety of manipulations, including varying asynchronies, intelligibility, and visual cue reliability. The causal inference model outperformed the Gaussian model across two experiments, providing a better fit to the behavioral data with fewer parameters. Because the causal inference model is derived from a principled understanding of the task, model parameters are directly interpretable in terms of stimulus and subject properties.

  14. Mind and Meaning: Piaget and Vygotsky on Causal Explanation.

    Science.gov (United States)

    Beilin, Harry

    1996-01-01

    Piaget's theory has been characterized as descriptive and not explanatory, not qualifying as causal explanation. Piaget was consistent in showing how his theory was both explanatory and causal. Vygotsky also endorsed causal-genetic explanation but, on the basis of knowledge of only Piaget's earliest works, he claimed that Piaget's theory was not…

  15. How to Be Causal: Time, Spacetime and Spectra

    Science.gov (United States)

    Kinsler, Paul

    2011-01-01

    I explain a simple definition of causality in widespread use, and indicate how it links to the Kramers-Kronig relations. The specification of causality in terms of temporal differential equations then shows us the way to write down dynamical models so that their causal nature "in the sense used here" should be obvious to all. To extend existing…

  16. Causal Relations and Feature Similarity in Children's Inductive Reasoning

    Science.gov (United States)

    Hayes, Brett K.; Thompson, Susan P.

    2007-01-01

    Four experiments examined the development of property induction on the basis of causal relations. In the first 2 studies, 5-year-olds, 8-year-olds, and adults were presented with triads in which a target instance was equally similar to 2 inductive bases but shared a causal antecedent feature with 1 of them. All 3 age groups used causal relations…

  17. Causal beliefs about depression in different cultural groups—what do cognitive psychological theories of causal learning and reasoning predict?

    OpenAIRE

    Hagmayer, York; Engelmann, Neele

    2014-01-01

    Cognitive psychological research focuses on causal learning and reasoning while cognitive anthropological and social science research tend to focus on systems of beliefs. Our aim was to explore how these two types of research can inform each other. Cognitive psychological theories (causal model theory and causal Bayes nets) were used to derive predictions for systems of causal beliefs. These predictions were then applied to lay theories of depression as a specific test case. A systematic lite...

  18. A Bayesian Theory of Sequential Causal Learning and Abstract Transfer.

    Science.gov (United States)

    Lu, Hongjing; Rojas, Randall R; Beckers, Tom; Yuille, Alan L

    2016-03-01

    Two key research issues in the field of causal learning are how people acquire causal knowledge when observing data that are presented sequentially, and the level of abstraction at which learning takes place. Does sequential causal learning solely involve the acquisition of specific cause-effect links, or do learners also acquire knowledge about abstract causal constraints? Recent empirical studies have revealed that experience with one set of causal cues can dramatically alter subsequent learning and performance with entirely different cues, suggesting that learning involves abstract transfer, and such transfer effects involve sequential presentation of distinct sets of causal cues. It has been demonstrated that pre-training (or even post-training) can modulate classic causal learning phenomena such as forward and backward blocking. To account for these effects, we propose a Bayesian theory of sequential causal learning. The theory assumes that humans are able to consider and use several alternative causal generative models, each instantiating a different causal integration rule. Model selection is used to decide which integration rule to use in a given learning environment in order to infer causal knowledge from sequential data. Detailed computer simulations demonstrate that humans rely on the abstract characteristics of outcome variables (e.g., binary vs. continuous) to select a causal integration rule, which in turn alters causal learning in a variety of blocking and overshadowing paradigms. When the nature of the outcome variable is ambiguous, humans select the model that yields the best fit with the recent environment, and then apply it to subsequent learning tasks. Based on sequential patterns of cue-outcome co-occurrence, the theory can account for a range of phenomena in sequential causal learning, including various blocking effects, primacy effects in some experimental conditions, and apparently abstract transfer of causal knowledge. Copyright © 2015

  19. Information causality from an entropic and a probabilistic perspective

    International Nuclear Information System (INIS)

    Al-Safi, Sabri W.; Short, Anthony J.

    2011-01-01

    The information causality principle is a generalization of the no-signaling principle which implies some of the known restrictions on quantum correlations. But despite its clear physical motivation, information causality is formulated in terms of a rather specialized game and figure of merit. We explore different perspectives on information causality, discussing the probability of success as the figure of merit, a relation between information causality and the nonlocal ''inner-product game,'' and the derivation of a quadratic bound for these games. We then examine an entropic formulation of information causality with which one can obtain the same results, arguably in a simpler fashion.

  20. Interactions of information transfer along separable causal paths

    Science.gov (United States)

    Jiang, Peishi; Kumar, Praveen

    2018-04-01

    Complex systems arise as a result of interdependences between multiple variables, whose causal interactions can be visualized in a time-series graph. Transfer entropy and information partitioning approaches have been used to characterize such dependences. However, these approaches capture net information transfer occurring through a multitude of pathways involved in the interaction and as a result mask our ability to discern the causal interaction within a subgraph of interest through specific pathways. We build on recent developments of momentary information transfer along causal paths proposed by Runge [Phys. Rev. E 92, 062829 (2015), 10.1103/PhysRevE.92.062829] to develop a framework for quantifying information partitioning along separable causal paths. Momentary information transfer along causal paths captures the amount of information transfer between any two variables lagged at two specific points in time. Our approach expands this concept to characterize the causal interaction in terms of synergistic, unique, and redundant information transfer through separable causal paths. Through a graphical model, we analyze the impact of the separable and nonseparable causal paths and the causality structure embedded in the graph as well as the noise effect on information partitioning by using synthetic data generated from two coupled logistic equation models. Our approach can provide a valuable reference for an autonomous information partitioning along separable causal paths which form a causal subgraph influencing a target.

  1. The selective power of causality on memory errors.

    Science.gov (United States)

    Marsh, Jessecae K; Kulkofsky, Sarah

    2015-01-01

    We tested the influence of causal links on the production of memory errors in a misinformation paradigm. Participants studied a set of statements about a person, which were presented as either individual statements or pairs of causally linked statements. Participants were then provided with causally plausible and causally implausible misinformation. We hypothesised that studying information connected with causal links would promote representing information in a more abstract manner. As such, we predicted that causal information would not provide an overall protection against memory errors, but rather would preferentially help in the rejection of misinformation that was causally implausible, given the learned causal links. In two experiments, we measured whether the causal linkage of information would be generally protective against all memory errors or only selectively protective against certain types of memory errors. Causal links helped participants reject implausible memory lures, but did not protect against plausible lures. Our results suggest that causal information may promote an abstract storage of information that helps prevent only specific types of memory errors.

  2. Causal asymmetry across cultures: Assigning causal roles in symmetric physical settings

    Directory of Open Access Journals (Sweden)

    Andrea eBender

    2011-09-01

    Full Text Available In the cognitive sciences, causal cognition in the physical domain has featured as a core research topic, but the impact of culture has been rarely ever explored. One case in point for a topic on which this neglect is pronounced is the pervasive tendency of people to consider one of two (equally important entities as more important for bringing about an effect. In order to scrutinize how robust such tendencies are across cultures, we asked German and Tongan participants to assign prime causality in nine symmetric settings. For most settings, strong asymmetries in both cultures were found, but not always in the same direction, depending on the task content. This indicates that causal asymmetries, while indeed being a robust phenomenon across cultures, are also subject to culture-specific concepts. Moreover, the asymmetries were found to be modulated by figure-ground relations, but not by marking agency.

  3. How multiple causes combine: independence constraints on causal inference.

    Science.gov (United States)

    Liljeholm, Mimi

    2015-01-01

    According to the causal power view, two core constraints-that causes occur independently (i.e., no confounding) and influence their effects independently-serve as boundary conditions for causal induction. This study investigated how violations of these constraints modulate uncertainty about the existence and strength of a causal relationship. Participants were presented with pairs of candidate causes that were either confounded or not, and that either interacted or exerted their influences independently. Consistent with the causal power view, uncertainty about the existence and strength of causal relationships was greater when causes were confounded or interacted than when unconfounded and acting independently. An elemental Bayesian causal model captured differences in uncertainty due to confounding but not those due to an interaction. Implications of distinct sources of uncertainty for the selection of contingency information and causal generalization are discussed.

  4. Fitossociologia e similaridade florística entre trechos de Cerrado sentido restrito em interflúvio e em vale no Jardim Botânico de Brasília, DF Phytossociology and floristic similarity between plateau and valley `Cerrado` woody vegetation in the Brasília Botanic Gardens, Federal District, Brazil

    Directory of Open Access Journals (Sweden)

    Mônica Souza da Fonseca

    2004-03-01

    Full Text Available Este estudo teve como objetivo verificar a composição florística, densidade e área basal do componente lenhoso do cerrado sentido restrito em duas situações num gradiente topográfico, designadas interflúvio (I e vale (V, no Jardim Botânico de Brasília, DF. Foram alocadas em cada área 10 parcelas permanentes de 20x50m para amostragem de todos os indivíduos com diâmetro basal DB(30cm> 5cm. A classificação por UPGMA (Índices de Sørensen e Morisita foi usada para a avaliação da similaridade entre parcelas. A análise da fitossociologia mostrou que as espécies mais importantes no interflúvio foram: Ouratea hexasperma (A. St.Hil Baill., Miconia ferruginata DC. e Dalbergia miscolobium Benth., enquanto que no vale foram: Eriotheca pubescens (Mart. & Zucc. Schott & Endl., Ouratea hexasperma (A. St.-Hil. Baill. e Schefflera macrocarpa (Seem D.C. Frodin. Os índices de similaridade variaram entre 0,26 a 0,81 (Sørensen e 0,06 a 0,92 (Morisita. A classificação por UPGMA indicou dois grupos principais, que coincidiram com as posições no relevo: interflúvio e vale. Os resultados salientaram a topografia como forte determinante na distribuição de algumas das populações e comunidades lenhosas, por meio de sua influência na variação da profundidade do lençol freático, que afetou a composição florística, a densidade (I/V=1.219/956 ind.ha-1 e a área basal (I/V=8,56/5,64m².ha-1 nos Cerrados sentido restrito de interflúvio (I e vale (V estudados.This study aims to check differences in the floristic composition and structure of the woody vegetation of the cerrado (sensu stricto in two distinct topographic positions, Interfluve (I and Valley Slope (V area in the Brasília Botanic Gardens, Federal District, Brazil. In each area ten 20x50m permanent plots were located to survey individuals, basal diameter BD(30cm > 5cm. UPGMA classification (Sørensen and Morisita similarity indices was used to assess similarity among plots

  5. Alienígenas na sala: o que fazer com espécies exóticas em trabalhos de taxonomia, florística e fitossociologia? Aliens in the room: what to do with exotic species in taxonomic, floristic and phytosociological studies?

    Directory of Open Access Journals (Sweden)

    Marcelo Freire Moro

    2012-12-01

    Full Text Available A presença cada vez mais disseminada de organismos exóticos (muitos dos quais se tornam invasores nas diferentes regiões do planeta levou ao surgimento de uma linha de pesquisa na ecologia voltada às invasões biológicas. E para permitir a comunicação entre autores também foi desenvolvido um arcabouço terminológico. Mas, apesar disso, a terminologia relativa às bioinvasões tem sido ignorada por boa parte dos botânicos no Brasil. Há uma boa dose de confusão entre botânicos sobre o que seja uma espécie exótica, naturalizada, invasora, daninha e ruderal, levando ao uso inconsistente da terminologia. Além disso, diferentes autores têm adotado posturas praticamente opostas ao lidar com espécies exóticas em suas áreas de estudo, seja na preparação de tratamentos taxonômicos, seja na publicação de levantamentos florísticos e fitossociológicos. Enquanto alguns pesquisadores incluem em floras mesmo espécies cultivadas que não se reproduzem, outros excluem plantas invasoras comuns e conspícuas. Nós apresentamos aqui, em português, os principais conceitos relativos ao tema da bioinvasão e chamamos a atenção dos autores brasileiros para a necessidade de utilizar de modo consistente o arcabouço terminológico já existente na literatura. Também propomos a adoção de rótulos claros para informar quais espécies são exóticas na área estudada, diferenciando-as das nativas, e sugerimos critérios para ajudar botânicos a decidirem quando uma planta exótica deve ou não ser incluída em tratamentos taxonômicos ou levantamentos de florística.The ever-growing presence of exotic organisms (many of which become invasive throughout the planet has led to the emergence of biological invasions as a field of study within ecology. To enable communication between scientists in this field, a terminology has developed. However, this terminology has been ignored by many botanists in Brazil where there is confusion regarding

  6. Avaliação do potencial biológico da Tabebuia aurea(Silva Manso como fonte de moléculas bioativas para atividade antimicrobiana, antiedematogênica e antirradicalar

    Directory of Open Access Journals (Sweden)

    R.F.E.P. SANTOS

    2015-01-01

    Full Text Available RESUMO As espécies da família Bignoniaceae e do gênero Tabebuia são amplamente utilizadas na medicina tradicional e possuem um forte potencial terapêutico. Diante disso, objetivou-se avaliar o potencial biológico da Tabebuia aurea, determinando a atividade antimicrobiana; por meio do método da microdiluição em caldo, para a determinação da Concentração Inibitória Mínima (CIM; antiedematogênica, pelo ensaio de edema de orelha induzido por capsaicina; e antirradicalar, frente ao radical DPPH. Os extratos etanólicos de T. aurea não evidenciaram citotoxicidade, exceto o extrato etanólico da flor nas concentrações > 0,5 mg mL-1. O extrato etanólico da flor foi ativo com ação bactericida frente a S. epidermidis (CIM de 0,06 mg mL-1 enquanto o extrato etanólico da folha foi moderadamente ativo frente a S. epidermidis (CIM: 0,25 mg mL-1 e S. aureus (CIM: 0,50 mg mL-1 sugerindo ação bacteriostática para ambas as linhagens. Os dois extratos apresentaram ação antiedematogênica, com inibição do edema de 40,50% pelo extrato etanólico da flor e de 41,73% pelo extrato da folha. T. aurea não apresentou atividade antirradicalar. Os resultados comprovam o perfil antibacteriano e antiedematogênico com ausência de citotoxidade pela T. aurea. Sugere-se a continuação dos testes com frações e substâncias isoladas das flores e folhas da referida espécie vegetal, bem como de experimentos in vivo, como forma de agregar evidências visando à busca de novos fitoterápicos.

  7. O sentido do uso ritual da ayahuasca em trabalho voltado ao tratamento e recuperação da população em situação de rua em São Paulo

    OpenAIRE

    Bruno Ramos Gomes

    2011-01-01

    Esta pesquisa visa a compreender o uso ritual da ayahuasca (chamado de Daime pelos participantes) na recuperação de pessoas em situação de rua pela Unidade de Resgate Flor das Águas Padrinho Sebastião, grupo situado em São Paulo. A ayahuasca é um chá feito da mistura de algumas plantas amazônicas, mais comumente o jagube e a chacrona, utilizado de forma ritual por populações indígenas e mestiças há muito tempo, e que leva a uma alteração na experiência de si e do mundo em sua ingestão. Vem ga...

  8. Emergent Geometry from Entropy and Causality

    Science.gov (United States)

    Engelhardt, Netta

    In this thesis, we investigate the connections between the geometry of spacetime and aspects of quantum field theory such as entanglement entropy and causality. This work is motivated by the idea that spacetime geometry is an emergent phenomenon in quantum gravity, and that the physics responsible for this emergence is fundamental to quantum field theory. Part I of this thesis is focused on the interplay between spacetime and entropy, with a special emphasis on entropy due to entanglement. In general spacetimes, there exist locally-defined surfaces sensitive to the geometry that may act as local black hole boundaries or cosmological horizons; these surfaces, known as holographic screens, are argued to have a connection with the second law of thermodynamics. Holographic screens obey an area law, suggestive of an association with entropy; they are also distinguished surfaces from the perspective of the covariant entropy bound, a bound on the total entropy of a slice of the spacetime. This construction is shown to be quite general, and is formulated in both classical and perturbatively quantum theories of gravity. The remainder of Part I uses the Anti-de Sitter/ Conformal Field Theory (AdS/CFT) correspondence to both expand and constrain the connection between entanglement entropy and geometry. The AdS/CFT correspondence posits an equivalence between string theory in the "bulk" with AdS boundary conditions and certain quantum field theories. In the limit where the string theory is simply classical General Relativity, the Ryu-Takayanagi and more generally, the Hubeny-Rangamani-Takayanagi (HRT) formulae provide a way of relating the geometry of surfaces to entanglement entropy. A first-order bulk quantum correction to HRT was derived by Faulkner, Lewkowycz and Maldacena. This formula is generalized to include perturbative quantum corrections in the bulk at any (finite) order. Hurdles to spacetime emergence from entanglement entropy as described by HRT and its quantum

  9. A Causal Theory of Mnemonic Confabulation

    Directory of Open Access Journals (Sweden)

    Sven Bernecker

    2017-07-01

    Full Text Available This paper attempts to answer the question of what defines mnemonic confabulation vis-à-vis genuine memory. The two extant accounts of mnemonic confabulation as “false memory” and as ill-grounded memory are shown to be problematic, for they cannot account for the possibility of veridical confabulation, ill-grounded memory, and well-grounded confabulation. This paper argues that the defining characteristic of mnemonic confabulation is that it lacks the appropriate causal history. In the confabulation case, there is no proper counterfactual dependence of the state of seeming to remember on the corresponding past representation.

  10. De Broglie's causal interpretations of quantum mechanics

    International Nuclear Information System (INIS)

    Ben-Dov, Y.

    1989-01-01

    In this article we trace the history of de Broglie's two causal interpretations of quantum mechanics, namely the double solution and the pilot wave theories, at the two periods in which he developed them: 1924-27 and 1952 onwards. Examining the reasons for which he always preferred the first theory to the second, reasons that are mainly concerned with the question of the physical nature of the quantum wave function, we try to show the continuity and the coherence of his underlying vision

  11. On asymmetric causal relationships in Petropolitics

    Directory of Open Access Journals (Sweden)

    Balan Feyza

    2016-01-01

    Full Text Available The aim of this paper is to examine whether the First Law of Petropolitics denominated by Friedman in 2006 is valid for OPEC countries. To do this, this paper analyses the relationship between political risk and oil supply by applying the asymmetric panel causality test suggested by Hatemi-J (2011 to these countries for the period 1984-2014. The results show that the First Law of Petropolitics is valid for Angola, Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi Arabia, and the UAE, given that positive oil supply shocks significantly lead to negative political stability shocks, and negative oil supply shocks significantly lead to positive shocks in political stability.

  12. Conditional Granger Causality of Diffusion Processes

    Czech Academy of Sciences Publication Activity Database

    Wahl, B.; Feudel, U.; Hlinka, Jaroslav; Wächter, M.; Peinke, J.; Freund, J.A.

    2017-01-01

    Roč. 90, č. 10 (2017), č. článku 197. ISSN 1434-6028 R&D Projects: GA ČR GA13-23940S; GA MZd(CZ) NV15-29835A Institutional support: RVO:67985807 Keywords : Granger causality * stochastic process * diffusion process * nonlinear dynamical systems Subject RIV: BB - Applied Statistics, Operational Research OBOR OECD: Computer sciences, information science, bioinformathics (hardware development to be 2.2, social aspect to be 5.8) Impact factor: 1.461, year: 2016

  13. Foundational perspectives on causality in large-scale brain networks

    Science.gov (United States)

    Mannino, Michael; Bressler, Steven L.

    2015-12-01

    A profusion of recent work in cognitive neuroscience has been concerned with the endeavor to uncover causal influences in large-scale brain networks. However, despite the fact that many papers give a nod to the important theoretical challenges posed by the concept of causality, this explosion of research has generally not been accompanied by a rigorous conceptual analysis of the nature of causality in the brain. This review provides both a descriptive and prescriptive account of the nature of causality as found within and between large-scale brain networks. In short, it seeks to clarify the concept of causality in large-scale brain networks both philosophically and scientifically. This is accomplished by briefly reviewing the rich philosophical history of work on causality, especially focusing on contributions by David Hume, Immanuel Kant, Bertrand Russell, and Christopher Hitchcock. We go on to discuss the impact that various interpretations of modern physics have had on our understanding of causality. Throughout all this, a central focus is the distinction between theories of deterministic causality (DC), whereby causes uniquely determine their effects, and probabilistic causality (PC), whereby causes change the probability of occurrence of their effects. We argue that, given the topological complexity of its large-scale connectivity, the brain should be considered as a complex system and its causal influences treated as probabilistic in nature. We conclude that PC is well suited for explaining causality in the brain for three reasons: (1) brain causality is often mutual; (2) connectional convergence dictates that only rarely is the activity of one neuronal population uniquely determined by another one; and (3) the causal influences exerted between neuronal populations may not have observable effects. A number of different techniques are currently available to characterize causal influence in the brain. Typically, these techniques quantify the statistical

  14. ¿CONFIEREN PODERES CAUSALES LOS UNIVERSALES TRASCENDENTES?

    Directory of Open Access Journals (Sweden)

    José Tomás Alvarado Marambio

    2013-11-01

    Full Text Available This work discusses the so-called ‘Eleatic’ argument against the existence of transcendent universals, i. e. universals which does not require instantiation for its existence. The Eleatic Principle states that everything produces a difference in the causal powers of something. As transcendent universals seem not to produce such a difference, transcendent universals seem not to exist. The argument depends crucially on the justification and the interpretation of the Eleatic Principle. It is argued, first, that it is not very clear that the principle is justified, and, second, that there are several alternatives for its interpretation, in relation with the different theories one can endorse about modality or causality. Anti-realist theories of modality or causality are not very appropriate for the understanding of what should be a ‘causal power’. Neither does a realist theory of causality conjoined with a combinatorial theory of possible worlds. A ‘causal power’ seems to be better understood in connection with a realist –non-reductionist– theory of causality and a causal theory of modality. Taken in this way the Eleatic Principle, nonetheless, it is argued that transcendent universals do ‘produce’ a difference in causal powers, for every causal connection requires such universals for its existence.

  15. Boraginaceae s.l. A. Juss. em uma área de Caatinga da ESEC Raso da Catarina, BA, Brasil Boraginaceae s.l. A. Juss. in the Caatinga of the Raso da Catarina Ecological Station, Bahia State, Brazil

    Directory of Open Access Journals (Sweden)

    José Iranildo Miranda de Melo

    2007-06-01

    Full Text Available Este trabalho trata do levantamento florístico-taxonômico da família Boraginaceae em um trecho de Caatinga da Estação Ecológica Raso da Catarina, Bahia, Brasil. Foram encontrados sete espécies e três gêneros de Boraginaceae: Cordia (C. globosa (Jacq. Kunth, C. leucocephala Moric. e C. rufescens A.DC., Heliotropium (H. angiospermum Murray e Heliotropium elongatum (Lehm. I.M. Johnst. e Tournefortia (T. rubicunda Salzm. ex A.DC. e T. salzmannii DC.. São apresentadas chaves para identificação de gêneros e espécies, além de descrições, ilustrações, comentários, dados de distribuição e hábitat.A floristic-taxonomic survey of the family Boraginaceae was carried out in a fragment of Caatinga vegetation of the Raso da Catarina Ecological Station, Bahia, Brazil. Seven species and three genera of Boraginaceae were found: Cordia (C. globosa (Jacq. Kunth; C. leucocephala Moric.; C. rufescens A.DC., Heliotropium (H. angiospermum Murray; H. elongatum (Lehm. I.M. Johnst. and Tournefortia (T. rubicunda Salzm. ex A.DC.; T. salzmannii DC.. Keys to identify genera and species are presented together with descriptions, illustrations, and comments on relationships among these taxa, distribution and habitat.

  16. Are bruxism and the bite causally related?

    Science.gov (United States)

    Lobbezoo, F; Ahlberg, J; Manfredini, D; Winocur, E

    2012-07-01

    In the dental profession, the belief that bruxism and dental (mal-)occlusion ('the bite') are causally related is widespread. The aim of this review was to critically assess the available literature on this topic. A PubMed search of the English-language literature, using the query 'Bruxism [Majr] AND (Dental Occlusion [Majr] OR Malocclusion [Majr])', yielded 93 articles, of which 46 papers were finally included in the present review*. Part of the included publications dealt with the possible associations between bruxism and aspects of occlusion, from which it was concluded that neither for occlusal interferences nor for factors related to the anatomy of the oro-facial skeleton, there is any evidence available that they are involved in the aetiology of bruxism. Instead, there is a growing awareness of other factors (viz. psychosocial and behavioural ones) being important in the aetiology of bruxism. Another part of the included papers assessed the possible mediating role of occlusion between bruxism and its purported consequences (e.g. tooth wear, loss of periodontal tissues, and temporomandibular pain and dysfunction). Even though most dentists agree that bruxism may have several adverse effects on the masticatory system, for none of these purported adverse effects, evidence for a mediating role of occlusion and articulation has been found to date. Hence, based on this review, it should be concluded that to date, there is no evidence whatsoever for a causal relationship between bruxism and the bite. © 2012 Blackwell Publishing Ltd.

  17. [Antibibiotic resistance by nosocomial infections' causal agents].

    Science.gov (United States)

    Salazar-Holguín, Héctor Daniel; Cisneros-Robledo, María Elena

    2016-01-01

    The antibibiotic resistance by nosocomial infections (NI) causal agents constitutes a seriously global problematic that involves the Mexican Institute of Social Security's Regional General Hospital 1 in Chihuahua, Mexico; although with special features that required to be specified and evaluated, in order to concrete an effective therapy. Observational, descriptive and prospective study; by means of active vigilance all along 2014 in order to detect the nosocomial infections, for epidemiologic study, culture and antibiogram to identify its causal agents and antibiotics resistance and sensitivity. Among 13527 hospital discharges, 1079 displayed NI (8 %), standed out: the related on vascular lines, of surgical site, pneumonia and urinal track; they added up two thirds of the total. We carried out culture and antibiogram about 300 of them (27.8 %); identifying 31 bacterian species, mainly seven of those (77.9 %): Escherichia coli, Staphylococcus aureus and epidermidis, Pseudomonas aeruginosa, Acinetobacter baumannii, Klebsiella pneumoniae and Enterobacter cloacae; showing multiresistance to 34 tested antibiotics, except in seven with low or without resistance at all: vancomycin, teicoplanin, linezolid, quinupristin-dalfopristin, piperacilin-tazobactam, amikacin and carbapenems. When we contrasted those results with the recommendations in the clinical practice guides, it aroused several contradictions; so they must be taken with reserves and has to be tested in each hospital, by means of cultures and antibiograms in practically every case of nosocomial infection.

  18. Diagnostic reasoning using qualitative causal models

    International Nuclear Information System (INIS)

    Sudduth, A.L.

    1992-01-01

    The application of expert systems to reasoning problems involving real-time data from plant measurements has been a topic of much research, but few practical systems have been deployed. One obstacle to wider use of expert systems in applications involving real-time data is the lack of adequate knowledge representation methodologies for dynamic processes. Knowledge bases composed mainly of rules have disadvantages when applied to dynamic processes and real-time data. This paper describes a methodology for the development of qualitative causal models that can be used as knowledge bases for reasoning about process dynamic behavior. These models provide a systematic method for knowledge base construction, considerably reducing the engineering effort required. They also offer much better opportunities for verification and validation of the knowledge base, thus increasing the possibility of the application of expert systems to reasoning about mission critical systems. Starting with the Signed Directed Graph (SDG) method that has been successfully applied to describe the behavior of diverse dynamic processes, the paper shows how certain non-physical behaviors that result from abstraction may be eliminated by applying causal constraint to the models. The resulting Extended Signed Directed Graph (ESDG) may then be compiled to produce a model for use in process fault diagnosis. This model based reasoning methodology is used in the MOBIAS system being developed by Duke Power Company under EPRI sponsorship. 15 refs., 4 figs

  19. Introducing mechanics by tapping core causal knowledge

    International Nuclear Information System (INIS)

    Klaassen, Kees; Westra, Axel; Emmett, Katrina; Eijkelhof, Harrie; Lijnse, Piet

    2008-01-01

    This article concerns an outline of an introductory mechanics course. It is based on the argument that various uses of the concept of force (e.g. from Kepler, Newton and everyday life) share an explanatory strategy based on core causal knowledge. The strategy consists of (a) the idea that a force causes a deviation from how an object would move of its own accord (i.e. its force-free motion), and (b) an incentive to search, where the motion deviates from the assumed force-free motion, for recurring configurations with which such deviations can be correlated (interaction theory). Various assumptions can be made concerning both the force-free motion and the interaction theory, thus giving rise to a variety of specific explanations. Kepler's semi-implicit intuition about the force-free motion is rest, Newton's explicit assumption is uniform rectilinear motion, while in everyday explanations a diversity of pragmatic suggestions can be recognized. The idea is that the explanatory strategy, once made explicit by drawing on students' intuitive causal knowledge, can be made to function for students as an advance organizer, in the sense of a general scheme that they recognize but do not yet know how to detail for scientific purposes

  20. Causal Inference in the Perception of Verticality.

    Science.gov (United States)

    de Winkel, Ksander N; Katliar, Mikhail; Diers, Daniel; Bülthoff, Heinrich H

    2018-04-03

    The perceptual upright is thought to be constructed by the central nervous system (CNS) as a vector sum; by combining estimates on the upright provided by the visual system and the body's inertial sensors with prior knowledge that upright is usually above the head. Recent findings furthermore show that the weighting of the respective sensory signals is proportional to their reliability, consistent with a Bayesian interpretation of a vector sum (Forced Fusion, FF). However, violations of FF have also been reported, suggesting that the CNS may rely on a single sensory system (Cue Capture, CC), or choose to process sensory signals based on inferred signal causality (Causal Inference, CI). We developed a novel alternative-reality system to manipulate visual and physical tilt independently. We tasked participants (n = 36) to indicate the perceived upright for various (in-)congruent combinations of visual-inertial stimuli, and compared models based on their agreement with the data. The results favor the CI model over FF, although this effect became unambiguous only for large discrepancies (±60°). We conclude that the notion of a vector sum does not provide a comprehensive explanation of the perception of the upright, and that CI offers a better alternative.

  1. Quantum causality conceptual issues in the causal theory of quantum mechanics

    CERN Document Server

    Riggs, Peter J; French, Steven RD

    2009-01-01

    This is a treatise devoted to the foundations of quantum physics and the role that causality plays in the microscopic world governed by the laws of quantum mechanics. The book is controversial and will engender some lively debate on the various issues raised.

  2. Links between causal effects and causal association for surrogacy evaluation in a gaussian setting.

    Science.gov (United States)

    Conlon, Anna; Taylor, Jeremy; Li, Yun; Diaz-Ordaz, Karla; Elliott, Michael

    2017-11-30

    Two paradigms for the evaluation of surrogate markers in randomized clinical trials have been proposed: the causal effects paradigm and the causal association paradigm. Each of these paradigms rely on assumptions that must be made to proceed with estimation and to validate a candidate surrogate marker (S) for the true outcome of interest (T). We consider the setting in which S and T are Gaussian and are generated from structural models that include an unobserved confounder. Under the assumed structural models, we relate the quantities used to evaluate surrogacy within both the causal effects and causal association frameworks. We review some of the common assumptions made to aid in estimating these quantities and show that assumptions made within one framework can imply strong assumptions within the alternative framework. We demonstrate that there is a similarity, but not exact correspondence between the quantities used to evaluate surrogacy within each framework, and show that the conditions for identifiability of the surrogacy parameters are different from the conditions, which lead to a correspondence of these quantities. Copyright © 2017 John Wiley & Sons, Ltd.

  3. Causal inference in nonlinear systems: Granger causality versus time-delayed mutual information

    Science.gov (United States)

    Li, Songting; Xiao, Yanyang; Zhou, Douglas; Cai, David

    2018-05-01

    The Granger causality (GC) analysis has been extensively applied to infer causal interactions in dynamical systems arising from economy and finance, physics, bioinformatics, neuroscience, social science, and many other fields. In the presence of potential nonlinearity in these systems, the validity of the GC analysis in general is questionable. To illustrate this, here we first construct minimal nonlinear systems and show that the GC analysis fails to infer causal relations in these systems—it gives rise to all types of incorrect causal directions. In contrast, we show that the time-delayed mutual information (TDMI) analysis is able to successfully identify the direction of interactions underlying these nonlinear systems. We then apply both methods to neuroscience data collected from experiments and demonstrate that the TDMI analysis but not the GC analysis can identify the direction of interactions among neuronal signals. Our work exemplifies inference hazards in the GC analysis in nonlinear systems and suggests that the TDMI analysis can be an appropriate tool in such a case.

  4. Trivariate causality between economic growth, urbanisation and electricity consumption in Angola: Cointegration and causality analysis

    International Nuclear Information System (INIS)

    Solarin, Sakiru Adebola; Shahbaz, Muhammad

    2013-01-01

    This paper investigates the causal relationship between economic growth, urbanisation and electricity consumption in the case of Angola, while utilizing the data over the period of 1971–2009. We have applied Lee and Strazicich (2003. The Review of Economics and Statistics 63, 1082–1089; 2004. Working Paper. Department of Economics, Appalachian State University) unit root tests to examine the stationarity properties of the series. Using the Gregory–Hansen structural break cointegration procedure as a complement, we employ the ARDL bounds test to investigate long run relationships. The VECM Granger causality test is subsequently used to examine the direction of causality between economic growth, urbanisation, and electricity consumption. Our results indicate the existence of long run relationships. We further observe evidence in favour of bidirectional causality between electricity consumption and economic growth. The feedback hypothesis is also found between urbanisation and economic growth. Urbanisation and electricity consumption Granger cause each other. We conclude that Angola is energy-dependent country. Consequently, the relevant authorities should boost electricity production as one of the means of achieving sustainable economic development in the long run. - Highlights: • We consider the link between electricity consumption and economic growth in Angola. • Urbanisation is added to turn the research into a trivariate investigation. • Various time series procedures are used. • Results show that increasing electricity will improve economic growth in Angola. • Results show urbanisations reduced economic growth during civil war

  5. Causality as a Rigorous Notion and Quantitative Causality Analysis with Time Series

    Science.gov (United States)

    Liang, X. S.

    2017-12-01

    Given two time series, can one faithfully tell, in a rigorous and quantitative way, the cause and effect between them? Here we show that this important and challenging question (one of the major challenges in the science of big data), which is of interest in a wide variety of disciplines, has a positive answer. Particularly, for linear systems, the maximal likelihood estimator of the causality from a series X2 to another series X1, written T2→1, turns out to be concise in form: T2→1 = [C11 C12 C2,d1 — C112 C1,d1] / [C112 C22 — C11C122] where Cij (i,j=1,2) is the sample covariance between Xi and Xj, and Ci,dj the covariance between Xi and ΔXj/Δt, the difference approximation of dXj/dt using the Euler forward scheme. An immediate corollary is that causation implies correlation, but not vice versa, resolving the long-standing debate over causation versus correlation. The above formula has been validated with touchstone series purportedly generated with one-way causality that evades the classical approaches such as Granger causality test and transfer entropy analysis. It has also been applied successfully to the investigation of many real problems. Through a simple analysis with the stock series of IBM and GE, an unusually strong one-way causality is identified from the former to the latter in their early era, revealing to us an old story, which has almost faded into oblivion, about "Seven Dwarfs" competing with a "Giant" for the computer market. Another example presented here regards the cause-effect relation between the two climate modes, El Niño and Indian Ocean Dipole (IOD). In general, these modes are mutually causal, but the causality is asymmetric. To El Niño, the information flowing from IOD manifests itself as a propagation of uncertainty from the Indian Ocean. In the third example, an unambiguous one-way causality is found between CO2 and the global mean temperature anomaly. While it is confirmed that CO2 indeed drives the recent global warming

  6. Variações florística e estrutural e relações fitogeográficas de um fragmento de floresta decídua no Rio Grande do Norte, Brasil Floristic and structural variations, and the phytogeographical relationships of a deciduous forest fragment in Rio Grande do Norte State, Brazil

    Directory of Open Access Journals (Sweden)

    Luiz Antonio Cestaro

    2004-06-01

    Full Text Available O trabalho foi realizado num fragmento de floresta decídua com cerca de 270ha centrado em 5°53'S e 35°23'W e que se estende por dois ambientes edáficos distintos (Moda 1 e Moda 2. Os objetivos do trabalho foram caracterizar florística e estruturalmente o componente arbóreo nos dois ambientes, compará-los entre si e avaliar suas relações fitogeográficas. Todos os indivíduos vivos e mortos em pé com perímetro à altura do peito >10cm foram considerados como árvore e amostrados pelo método dos quadrantes. Para Moda 1 e Moda 2 foram estimados, respectivamente: densidade total de 1.587 e de 1.924 indivíduos.ha-1, área basal total de 15,88 e de 15,86m².ha-¹, freqüências modais das alturas entre 5 e 5,9m e entre 6 e 6,9m e dos diâmetros de caule entre 5,0 e 9,9cm e entre 3,2 e 4,9cm, índice de diversidade de Shannon de 3,19 e de 3,26 e índice de eqüabilidade de Pielou de 0,79 e de 0,86. Os estratos arbóreos nos dois ambientes foram considerados estruturalmente semelhantes. Foram observadas no total 66 espécies de árvores, sendo 56 em Moda 1 e 45 em Moda 2. Piptadenia moniliformis Benth. é a espécie com maior valor de importância nas duas áreas, seguidas por Tabebuia impetiginosa (Mart. ex DC. Standl. em Moda 1 e por Chamaecrista ensiformis (Vell. H.S. Irwin & Barneby em Moda 2. As áreas apresentam grande similaridade florística (S S = 0,69 e S C = 0,53, sendo que as espécies características de matas decíduas são mais abundantes em ou exclusivas de Moda 1, e as espécies características das Caatingas, em Moda 2. As pequenas diferenças florística e estrutural entre os dois setores da mata podem ser atribuídas às condições edáficas. Em termos florísticos, fisionômicos e ambientais, a mata foi classificada como um tipo de vegetação de transição entre as províncias fitogeográficas Atlântica e das Caatingas, com a presença destacada de espécies com ampla distribuição nas matas secas neotropicais e

  7. Morfología de la flor y de la semilla de papaya (Carica papaya L.: variedad Maradol e híbrido Tainung-1

    Directory of Open Access Journals (Sweden)

    Gil Arlette Ivonne

    2005-12-01

    Full Text Available

    Con el objetivo de analizar la morfología de la flor y de la semilla de papaya (Carica papaya L. de la variedad ‘Maradol’ y el híbrido ‘Tainung-1’, se recolectó el material vegetal en dos plantaciones y se llevaron al laboratorio de Fisiología de Cultivos, Facultad de Agronomía, Universidad Nacional de Colombia, Bogotá, con el fin de realizar las descripciones correspondientes de los tres tipos de flores (femeninas, hermafroditas y estaminadas y de la semilla, sus características externas (forma, tamaño, hilo, micrópilo, funículo, rafe y cubierta seminal e internas (cubierta seminal, endospermo y embrión. Se concluyó principalmente que a nivel morfológico las flores y semillas de los dos materiales evaluados mostraron características similares, por tanto, las descripciones dadas en este trabajo son generales para ambos.

  8. La organización de eventos como estrategia identitaria y evocadora de imagen turística. Estudio de caso: Girona Temps de Flors

    Directory of Open Access Journals (Sweden)

    Mònika Jiménez Morales

    2009-01-01

    Full Text Available Desde hace 53 años la ciudad de Girona organiza un evento multitudinario basado en el arte floral que, en sus últimas ediciones, ha llegado a movilizar a más de medio millón de visitantes, muchos de ellos llegados de todas partes de Europa. Más allá de las flores, las exposiciones fotográficas o los montajes audiovisuales que llenan las calles del casco antiguo del municipio durante la segunda semana del mes de mayo, lo cierto es que Girona Temps de Flors representa la puesta en escena de una estrategia comunicativa emergente en el ámbito de la promoción del territorio. En efecto, el evento desempeña, per se, variadas funciones en el ámbito emocional del espacio vivido, pero hay más. También puede devenir a modo de catalizador de imágenes, de creador de imaginarios capaces de fijar una marca de ciudad en su conjunto. El presente artículo dará a conocer las posibilidades que se desprenden de la organización de un evento en relación al posicionamiento identitario y de marca de un territorio.

  9. Caracterización de las antocianinas de la flor de ceibo como sensibilizadores naturales para su uso en celdas fotovoltaicas

    Directory of Open Access Journals (Sweden)

    María Paula Enciso

    2014-12-01

    Full Text Available La energía solar es la fuente de energía más promisoria del futuro, ya que la conversión directa de luz solar en energía eléctrica mediante el uso de celdas solares posee muchas ventajas sobre los métodos usados en la actualidad, debido a que no genera desechos o contaminantes.En particular, las celdas solares sensibilizadas con pigmentos (DSSC o celdas de Graetzel representan una alternativa a las convencionales celdas solares de silicio. En las últimas tres décadas han atraído considerable atención como una forma de producir celdas fotovoltaicas de bajo costo debido a la posibilidad de alcanzar una alta eficiencia de conversión (de aprox. 12% y su alto rendimiento durante períodos de luz prolongados e incluso en condiciones de stress térmico.En este trabajo se evalúan pigmentos de origen natural, la mezcla de antocianinas provenientes de la flor del ceibo, como sensibilizadores de estas celdas. Se utilizan medidas de absorbancia UV-visible, voltamperometría cíclica y espectroscopía de impedancia electroquímica como forma de caracterización.

  10. FLORÍSTICA DE MATA CILIAR EM SÃO MARTINHO DA SERRA, RS, BRASIL

    OpenAIRE

    Maria Carolina dos Santos Figueiredo

    2014-01-01

    Matas ciliares são formações vegetais associadas a ambientes com cursos d`água, valorizadas, principalmente, pelas funções de estabilizar as margens dos rios e permitir o fluxo gênico de espécies. O objetivo deste trabalho foi o de realizar o levantamento florístico do estrato herbáceo e do estrato arbustivo-arbóreo e de sua regeneração natural em uma mata ciliar localizada no município de São Martinho da Serra, RS, região de transição entre os Biomas Pampa e Mata Atlântica. A área de estudo ...

  11. Entanglement, non-Markovianity, and causal non-separability

    Science.gov (United States)

    Milz, Simon; Pollock, Felix A.; Le, Thao P.; Chiribella, Giulio; Modi, Kavan

    2018-03-01

    Quantum mechanics, in principle, allows for processes with indefinite causal order. However, most of these causal anomalies have not yet been detected experimentally. We show that every such process can be simulated experimentally by means of non-Markovian dynamics with a measurement on additional degrees of freedom. In detail, we provide an explicit construction to implement arbitrary a causal processes. Furthermore, we give necessary and sufficient conditions for open system dynamics with measurement to yield processes that respect causality locally, and find that tripartite entanglement and nonlocal unitary transformations are crucial requirements for the simulation of causally indefinite processes. These results show a direct connection between three counter-intuitive concepts: entanglement, non-Markovianity, and causal non-separability.

  12. Ecologia da polinização da amoreira-preta (Rubus sp (Rosaceae em Timbó-SC, Brasil

    Directory of Open Access Journals (Sweden)

    Leônidas João de Mello Junior

    2011-09-01

    Full Text Available O presente trabalho verificou experimentalmente a ecologia da polinização da amoreira-preta (Rubus sp.. Objetivou-se confirmar a síndrome de polinização de Rubus sp., por meio de análise de seu sistema reprodutivo, quantificação da produção diária de néctar, levantamento da entomofauna que visita as flores da amoreira na área de estudo e análise do seu comportamento polinizador. Os experimentos foram realizados em uma área de cultivo de amoreira-preta, no mês de dezembro de 2005, município de Timbó (SC. Constatou-se que a maior taxa de frutificação (48,3 % ± 3,2 ocorreu via polinização livre, onde os insetos não foram excluídos. Foi verificada a ocorrência de autopolinização, porém com taxa inferior de frutificação (12,2% ± 4,9. A anemofilia não foi constatada na espécie. A avaliação da produção de néctar em Rubus sp. resultou em valores compatíveis com a síndrome de melitofilia. Os visitantes florais coletados e observados sobre as flores de Rubus sp. foram predominantemente abelhas da ordem Hymenoptera (97%, que iniciam, em menor número, a atividade de forrageamento às 8h, com pico de atividade às 12h e declinando até às 16h. As coletas resultaram numa amostragem de 1.360 abelhas, divididas em quatro famílias e 13 espécies. A família com maior riqueza de espécies (N = 7 foi Halictidae e a mais abundante foi Apidae, com 1.288 indivíduos. Em Apidae, houve o predomínio da espécie exótica Apis mellifera, cuja representação na amostra foi de 1.246 indivíduos. Os dados da abundância e as observações naturalísticas do seu comportamento da flor apontaram A. mellifera como o principal polinizador de Rubus sp., mas confirmam que as demais espécies de abelhas também participam na polinização de Rubus sp.

  13. Causal theory in (2+1)-dimensional Qed

    International Nuclear Information System (INIS)

    Scharf, G.; Wreszinski, W.F.

    1994-01-01

    The program of constructing the S-matrix by means of causality in quantum field theory goes back to Stueckelberg and Bogoliubov. Epstein and Glaser proposed an axiomatic construct where ultraviolet divergences do not appear, leading directly to the renormalized perturbation series. They have shown that in the causal theory the UV problem is a consequence of incorrect distribution splitting. This paper studies the causal theory in (2+1)D Qed

  14. Causal knowledge and the development of inductive reasoning

    OpenAIRE

    Bright, Aimée K.; Feeney, Aidan

    2014-01-01

    We explored the development of sensitivity to causal relations in children’s inductive reasoning. Children (5-, 8-, and 12-year-olds) and adults were given trials in which they decided whether a property known to be possessed by members of one category was also possessed by members of (a) a taxonomically related category or (b) a causally related category. The direction of the causal link was either predictive (prey → predator) or diagnostic (predator → prey), and the property that participan...

  15. Floristic composition and growth of weeds under custard apple (Annona squamosa progenies Composição florística e crescimento de plantas daninhas sob a copa de progênies de fruta-do-conde (Annona squamosa

    Directory of Open Access Journals (Sweden)

    P.S.L. Silva

    2004-12-01

    ção ambiental. Dentre esses métodos, a adoção de cultivares com maior habilidade competitiva com as PD tem despertado atenção internacional. O objetivo do trabalho foi avaliar a composição florística e o crescimento de PD sob a copa de progênies de pinheira irrigadas. Vinte progênies de meias-irmãs, com idade aproximada de três anos, foram avaliadas no delineamento de blocos ao acaso, com cinco repetições e quatro plantas por parcela. Ao redor do caule de cada planta estabeleceu-se um círculo com área de 0,5 m². Nessa área, foram avaliadas a composição e as massas das matérias fresca e seca da parte aérea das PD. Avaliaram-se também os diâmetros do colo e da copa e a área da folha das progênies. Ocorreram 58 espécies de PD. As famílias com maior número de espécies, em ordem decrescente, foram Leguminosae, Convolvulaceae, Euphorbiaceae, Malvaceae e Sterculiaceae. O número de espécies de PD/parcela variou de 6 a 18, porém não houve diferença entre a porcentagem média de diferentes PD sob a copa das progênies. As menores massas de matérias fresca e seca de PD ocorreram nas progênies JG1 e SM8, respectivamente. Não houve diferenças entre progênies quanto a diâmetro do colo e área foliar, mas sob a copa da progênie FE4, que apresentou o maior diâmetro da copa, observou-se um dos menores rendimentos de matéria seca de PD.

  16. Analogy in causal inference: rethinking Austin Bradford Hill's neglected consideration.

    Science.gov (United States)

    Weed, Douglas L

    2018-05-01

    The purpose of this article was to rethink and resurrect Austin Bradford Hill's "criterion" of analogy as an important consideration in causal inference. In epidemiology today, analogy is either completely ignored (e.g., in many textbooks), or equated with biologic plausibility or coherence, or aligned with the scientist's imagination. None of these examples, however, captures Hill's description of analogy. His words suggest that there may be something gained by contrasting two bodies of evidence, one from an established causal relationship, the other not. Coupled with developments in the methods of systematic assessments of evidence-including but not limited to meta-analysis-analogy can be restructured as a key component in causal inference. This new approach will require that a collection-a library-of known cases of causal inference (i.e., bodies of evidence involving established causal relationships) be developed. This library would likely include causal assessments by organizations such as the International Agency for Research on Cancer, the National Toxicology Program, and the United States Environmental Protection Agency. In addition, a process for describing key features of a causal relationship would need to be developed along with what will be considered paradigm cases of causation. Finally, it will be important to develop ways to objectively compare a "new" body of evidence with the relevant paradigm case of causation. Analogy, along with all other existing methods and causal considerations, may improve our ability to identify causal relationships. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. Granger Causality and Transfer Entropy Are Equivalent for Gaussian Variables

    Science.gov (United States)

    Barnett, Lionel; Barrett, Adam B.; Seth, Anil K.

    2009-12-01

    Granger causality is a statistical notion of causal influence based on prediction via vector autoregression. Developed originally in the field of econometrics, it has since found application in a broader arena, particularly in neuroscience. More recently transfer entropy, an information-theoretic measure of time-directed information transfer between jointly dependent processes, has gained traction in a similarly wide field. While it has been recognized that the two concepts must be related, the exact relationship has until now not been formally described. Here we show that for Gaussian variables, Granger causality and transfer entropy are entirely equivalent, thus bridging autoregressive and information-theoretic approaches to data-driven causal inference.

  18. Explaining quantum correlations through evolution of causal models

    Science.gov (United States)

    Harper, Robin; Chapman, Robert J.; Ferrie, Christopher; Granade, Christopher; Kueng, Richard; Naoumenko, Daniel; Flammia, Steven T.; Peruzzo, Alberto

    2017-04-01

    We propose a framework for the systematic and quantitative generalization of Bell's theorem using causal networks. We first consider the multiobjective optimization problem of matching observed data while minimizing the causal effect of nonlocal variables and prove an inequality for the optimal region that both strengthens and generalizes Bell's theorem. To solve the optimization problem (rather than simply bound it), we develop a genetic algorithm treating as individuals causal networks. By applying our algorithm to a photonic Bell experiment, we demonstrate the trade-off between the quantitative relaxation of one or more local causality assumptions and the ability of data to match quantum correlations.

  19. A general, multivariate definition of causal effects in epidemiology.

    Science.gov (United States)

    Flanders, W Dana; Klein, Mitchel

    2015-07-01

    Population causal effects are often defined as contrasts of average individual-level counterfactual outcomes, comparing different exposure levels. Common examples include causal risk difference and risk ratios. These and most other examples emphasize effects on disease onset, a reflection of the usual epidemiological interest in disease occurrence. Exposure effects on other health characteristics, such as prevalence or conditional risk of a particular disability, can be important as well, but contrasts involving these other measures may often be dismissed as non-causal. For example, an observed prevalence ratio might often viewed as an estimator of a causal incidence ratio and hence subject to bias. In this manuscript, we provide and evaluate a definition of causal effects that generalizes those previously available. A key part of the generalization is that contrasts used in the definition can involve multivariate, counterfactual outcomes, rather than only univariate outcomes. An important consequence of our generalization is that, using it, one can properly define causal effects based on a wide variety of additional measures. Examples include causal prevalence ratios and differences and causal conditional risk ratios and differences. We illustrate how these additional measures can be useful, natural, easily estimated, and of public health importance. Furthermore, we discuss conditions for valid estimation of each type of causal effect, and how improper interpretation or inferences for the wrong target population can be sources of bias.

  20. Delinquency among pathological gamblers: A causal approach.

    Science.gov (United States)

    Meyer, G; Fabian, T

    1992-03-01

    In a comprehensive research project on gamblers in self-help groups in West Germany one object of investigation was the question of whether or not pathological gambling has a criminogenic effect. 54.5% of the 437 members of Gamblers Anonymous interviewed stated that they had committed illegal actions in order to obtain money for gambling. Comparisons of this sub-group with those interviewees who did not admit having committed criminal offences show distinct differences: Those who admitted illegal action were more excessive in their gambling behavior and experienced a higher degree of subjective satisfaction through gambling. They also showed a more pronounced problem behavior and more psychosocial problems because of gambling. A multiple regression within the framework of path analysis was computed in order to explore causal links between pathological gambling and delinquency. The results support the hypothesis that pathological gambling can lead to delinquent behavior. Forensic implications are discussed.

  1. Exploring Torus Universes in Causal Dynamical Triangulations

    DEFF Research Database (Denmark)

    Budd, Timothy George; Loll, R.

    2013-01-01

    Motivated by the search for new observables in nonperturbative quantum gravity, we consider Causal Dynamical Triangulations (CDT) in 2+1 dimensions with the spatial topology of a torus. This system is of particular interest, because one can study not only the global scale factor, but also global...... shape variables in the presence of arbitrary quantum fluctuations of the geometry. Our initial investigation focusses on the dynamics of the scale factor and uncovers a qualitatively new behaviour, which leads us to investigate a novel type of boundary conditions for the path integral. Comparing large....... Apart from setting the stage for the analysis of shape dynamics on the torus, the new set-up highlights the role of nontrivial boundaries and topology....

  2. Causality Constraints in Conformal Field Theory

    CERN Multimedia

    CERN. Geneva

    2015-01-01

    Causality places nontrivial constraints on QFT in Lorentzian signature, for example fixing the signs of certain terms in the low energy Lagrangian. In d-dimensional conformal field theory, we show how such constraints are encoded in crossing symmetry of Euclidean correlators, and derive analogous constraints directly from the conformal bootstrap (analytically). The bootstrap setup is a Lorentzian four-point function corresponding to propagation through a shockwave. Crossing symmetry fixes the signs of certain log terms that appear in the conformal block expansion, which constrains the interactions of low-lying operators. As an application, we use the bootstrap to rederive the well known sign constraint on the (∂φ)4 coupling in effective field theory, from a dual CFT. We also find constraints on theories with higher spin conserved currents. Our analysis is restricted to scalar correlators, but we argue that similar methods should also impose nontrivial constraints on the interactions of spinni...

  3. Equity Theory Ratios as Causal Schemas

    Directory of Open Access Journals (Sweden)

    Alexios Arvanitis

    2016-08-01

    Full Text Available Equity theory approaches justice evaluations based on ratios of exchange inputs to exchange outcomes. Situations are evaluated as just if ratios are equal and unjust if unequal. We suggest that equity ratios serve a more fundamental cognitive function than the evaluation of justice. More particularly, we propose that they serve as causal schemas for exchange outcomes, that is, they assist in determining whether certain outcomes are caused by inputs of other people in the context of an exchange process. Equality or inequality of ratios in this sense points to an exchange process. Indeed, Study 1 shows that different exchange situations, such as disproportional or balanced proportional situations, create perceptions of give-and-take on the basis of equity ratios. Study 2 shows that perceptions of justice are based more on communicatively accepted rules of interaction than equity-based evaluations, thereby offering a distinction between an attribution and an evaluation cognitive process for exchange outcomes.

  4. The emerging causal understanding of institutional objects.

    Science.gov (United States)

    Noyes, Alexander; Keil, Frank C; Dunham, Yarrow

    2018-01-01

    Institutional objects, such as money, drivers' licenses, and borders, have functions because of their social roles rather than their immediate physical properties. These objects are causally different than standard artifacts (e.g. hammers, chairs, and cars), sharing more commonality with other social roles. Thus, they inform psychological theories of human-made objects as well as children's emerging understanding of social reality. We examined whether children (N=180, ages 4-9) differentiate institutional objects from standard artifacts. Specifically, we examine whether children understand that mutual intentions (i.e., the intentions of a social collective) underlie the functional affordances of institutional objects in ways that they do not for standard artifacts. We find that young children assimilate institutional objects into their intuitive theories of standard artifacts; children begin to differentiate between the domains in the elementary school years. Published by Elsevier B.V.

  5. A study in cosmology and causal thermodynamics

    International Nuclear Information System (INIS)

    Oliveira, H.P. de.

    1986-01-01

    The especial relativity of thermodynamic theories for reversible and irreversible processes in continuous medium is studied. The formalism referring to equilibrium and non-equilibrium configurations, and theories which includes the presence of gravitational fields are discussed. The nebular model in contraction with dissipative processes identified by heat flux and volumetric viscosity is thermodymically analysed. This model is presented by a plane conformal metric. The temperature, pressure, entropy and entropy production within thermodynamic formalism which adopts the hypothesis of local equilibrium, is calculated. The same analysis is carried out considering a causal thermodynamics, which establishes a local entropy of non-equilibrium. Possible homogeneous and isotropic cosmological models, considering the new phenomenological equation for volumetric viscosity deriving from cause thermodynamics are investigated. The found out models have plane spatial section (K=0) and some ones do not have singularities. The energy conditions are verified and the entropy production for physically reasobable models are calculated. (M.C.K.) [pt

  6. Equity Theory Ratios as Causal Schemas.

    Science.gov (United States)

    Arvanitis, Alexios; Hantzi, Alexandra

    2016-01-01

    Equity theory approaches justice evaluations based on ratios of exchange inputs to exchange outcomes. Situations are evaluated as just if ratios are equal and unjust if unequal. We suggest that equity ratios serve a more fundamental cognitive function than the evaluation of justice. More particularly, we propose that they serve as causal schemas for exchange outcomes, that is, they assist in determining whether certain outcomes are caused by inputs of other people in the context of an exchange process. Equality or inequality of ratios in this sense points to an exchange process. Indeed, Study 1 shows that different exchange situations, such as disproportional or balanced proportional situations, create perceptions of give-and-take on the basis of equity ratios. Study 2 shows that perceptions of justice are based more on communicatively accepted rules of interaction than equity-based evaluations, thereby offering a distinction between an attribution and an evaluation cognitive process for exchange outcomes.

  7. Causality and hyperbolicity of Lovelock theories

    International Nuclear Information System (INIS)

    Reall, Harvey S; Tanahashi, Norihiro; Way, Benson

    2014-01-01

    In Lovelock theories, gravity can travel faster or slower than light. The causal structure is determined by the characteristic hypersurfaces. We generalize a recent result of Izumi to prove that any Killing horizon is a characteristic hypersurface for all gravitational degrees of freedom of a Lovelock theory. Hence gravitational signals cannot escape from the region inside such a horizon. We investigate the hyperbolicity of Lovelock theories by determining the characteristic hypersurfaces for various backgrounds. First we consider Ricci flat type N spacetimes. We show that characteristic hypersurfaces are generically all non-null and that Lovelock theories are hyperbolic in any such spacetime. Next we consider static, maximally symmetric black hole solutions of Lovelock theories. Again, characteristic surfaces are generically non-null. For some small black holes, hyperbolicity is violated near the horizon. This implies that the stability of such black holes is not a well-posed problem. (paper)

  8. Causality constraints in conformal field theory

    Energy Technology Data Exchange (ETDEWEB)

    Hartman, Thomas; Jain, Sachin; Kundu, Sandipan [Department of Physics, Cornell University,Ithaca, New York (United States)

    2016-05-17

    Causality places nontrivial constraints on QFT in Lorentzian signature, for example fixing the signs of certain terms in the low energy Lagrangian. In d dimensional conformal field theory, we show how such constraints are encoded in crossing symmetry of Euclidean correlators, and derive analogous constraints directly from the conformal bootstrap (analytically). The bootstrap setup is a Lorentzian four-point function corresponding to propagation through a shockwave. Crossing symmetry fixes the signs of certain log terms that appear in the conformal block expansion, which constrains the interactions of low-lying operators. As an application, we use the bootstrap to rederive the well known sign constraint on the (∂ϕ){sup 4} coupling in effective field theory, from a dual CFT. We also find constraints on theories with higher spin conserved currents. Our analysis is restricted to scalar correlators, but we argue that similar methods should also impose nontrivial constraints on the interactions of spinning operators.

  9. Caracterização florística de comunidades vegetais de restinga em Bertioga, SP, Brasil Floristic characterization of "restinga" plant communities at Bertioga, São Paulo State, Brazil

    Directory of Open Access Journals (Sweden)

    Suzana Ehlin Martins

    2008-03-01

    Full Text Available O município de Bertioga, no litoral central do Estado de São Paulo, apresenta grandes extensões de restingas ainda preservadas, com reduzido número de coletas de material botânico. A rápida devastação desse tipo de ambiente, por pressão de empreendedores do ramo imobiliário e outras intervenções antrópicas, torna urgente a compilação de dados que subsidiem estratégias conservacionistas. Nesse aspecto, é aqui apresentada a caracterização florística das comunidades vegetais da região que abrange as restingas de Itaguaré, São Lourenço e Guaratuba, situada entre 23º44'-23º46'S e 45º55'-46º02'W. A classificação das comunidades vegetais seguiu, sempre que possível, os critérios estabelecidos pela Resolução CONAMA n. 7/96, legislação ambiental federal, que aprova diretrizes para análise dos estágios de sucessão de vegetação de restinga para o Estado de São Paulo. Foram reconhecidas as comunidades vegetais de Praia e Dunas (33 espécies, Escrube (101, Floresta Alta de Restinga (301, Floresta Alta de Restinga Úmida (434 e Vegetação Entre Cordões (45. Foram registradas 611 espécies, representando 351 gêneros distribuídos em 106 famílias, das quais as de maior riqueza específica são: Orchidaceae (47 espécies, Myrtaceae (39, Bromeliaceae (36, Asteraceae (35, Rubiaceae (34, Fabaceae (32, Cyperaceae (23, Melastomataceae (19, Poaceae (19 e Solanaceae (15.The municipality of Bertioga, located on the central coast of São Paulo state, still has large areas of preserved 'restingas', where few botanical collections have been made. The rapidly growing devastation of this type of environment due to real-estate development and other human interventions makes urgent the need for data that support conservation strategies. For this reason, we characterize floristically the plant communities of the 'restingas' of Itaguaré, São Lourenço and Guaratuba (23º44'-23º46'S; 45º55'-46º02'W. Community classification

  10. Diagnostic causal reasoning with verbal information.

    Science.gov (United States)

    Meder, Björn; Mayrhofer, Ralf

    2017-08-01

    In diagnostic causal reasoning, the goal is to infer the probability of causes from one or multiple observed effects. Typically, studies investigating such tasks provide subjects with precise quantitative information regarding the strength of the relations between causes and effects or sample data from which the relevant quantities can be learned. By contrast, we sought to examine people's inferences when causal information is communicated through qualitative, rather vague verbal expressions (e.g., "X occasionally causes A"). We conducted three experiments using a sequential diagnostic inference task, where multiple pieces of evidence were obtained one after the other. Quantitative predictions of different probabilistic models were derived using the numerical equivalents of the verbal terms, taken from an unrelated study with different subjects. We present a novel Bayesian model that allows for incorporating the temporal weighting of information in sequential diagnostic reasoning, which can be used to model both primacy and recency effects. On the basis of 19,848 judgments from 292 subjects, we found a remarkably close correspondence between the diagnostic inferences made by subjects who received only verbal information and those of a matched control group to whom information was presented numerically. Whether information was conveyed through verbal terms or numerical estimates, diagnostic judgments closely resembled the posterior probabilities entailed by the causes' prior probabilities and the effects' likelihoods. We observed interindividual differences regarding the temporal weighting of evidence in sequential diagnostic reasoning. Our work provides pathways for investigating judgment and decision making with verbal information within a computational modeling framework. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. The balanced survivor average causal effect.

    Science.gov (United States)

    Greene, Tom; Joffe, Marshall; Hu, Bo; Li, Liang; Boucher, Ken

    2013-05-07

    Statistical analysis of longitudinal outcomes is often complicated by the absence of observable values in patients who die prior to their scheduled measurement. In such cases, the longitudinal data are said to be "truncated by death" to emphasize that the longitudinal measurements are not simply missing, but are undefined after death. Recently, the truncation by death problem has been investigated using the framework of principal stratification to define the target estimand as the survivor average causal effect (SACE), which in the context of a two-group randomized clinical trial is the mean difference in the longitudinal outcome between the treatment and control groups for the principal stratum of always-survivors. The SACE is not identified without untestable assumptions. These assumptions have often been formulated in terms of a monotonicity constraint requiring that the treatment does not reduce survival in any patient, in conjunction with assumed values for mean differences in the longitudinal outcome between certain principal strata. In this paper, we introduce an alternative estimand, the balanced-SACE, which is defined as the average causal effect on the longitudinal outcome in a particular subset of the always-survivors that is balanced with respect to the potential survival times under the treatment and control. We propose a simple estimator of the balanced-SACE that compares the longitudinal outcomes between equivalent fractions of the longest surviving patients between the treatment and control groups and does not require a monotonicity assumption. We provide expressions for the large sample bias of the estimator, along with sensitivity analyses and strategies to minimize this bias. We consider statistical inference under a bootstrap resampling procedure.

  12. World oil and agricultural commodity prices: Evidence from nonlinear causality

    International Nuclear Information System (INIS)

    Nazlioglu, Saban

    2011-01-01

    The increasing co-movements between the world oil and agricultural commodity prices have renewed interest in determining price transmission from oil prices to those of agricultural commodities. This study extends the literature on the oil-agricultural commodity prices nexus, which particularly concentrates on nonlinear causal relationships between the world oil and three key agricultural commodity prices (corn, soybeans, and wheat). To this end, the linear causality approach of Toda-Yamamoto and the nonparametric causality method of Diks-Panchenko are applied to the weekly data spanning from 1994 to 2010. The linear causality analysis indicates that the oil prices and the agricultural commodity prices do not influence each other, which supports evidence on the neutrality hypothesis. In contrast, the nonlinear causality analysis shows that: (i) there are nonlinear feedbacks between the oil and the agricultural prices, and (ii) there is a persistent unidirectional nonlinear causality running from the oil prices to the corn and to the soybeans prices. The findings from the nonlinear causality analysis therefore provide clues for better understanding the recent dynamics of the agricultural commodity prices and some policy implications for policy makers, farmers, and global investors. This study also suggests the directions for future studies. - Research highlights: → This study determines the price transmission mechanisms between the world oil and three key agricultural commodity prices (corn, soybeans, and wheat). → The linear and nonlinear cointegration and causality methods are carried out. → The linear causality analysis supports evidence on the neutrality hypothesis. → The nonlinear causality analysis shows that there is a persistent unidirectional causality from the oil prices to the corn and to the soybeans prices.

  13. Tachyon kinematics and causality: a systematic thorough analysis of the tachyon causal paradoxes

    International Nuclear Information System (INIS)

    Recami, E.

    1987-01-01

    The chronological order of the events along a spacelike path is not invariant under Lorentz transformations, as is well known. This led to an early conviction that tachyons would give rise to causal anomalies. A relativistic version of the Stueckelberg-Feynman switching procedure (SWP) has been invoked as the suitable tool to eliminate those anomalies. The application of the SWP does eliminate the motions backwards in time, but interchanges the roles of source and detector. This fact triggered the proposal of a host of causal paradoxes. Till now, however, it has not been recognized that such paradoxes can be sensibly discussed (and completely solved, at least in microphysics) only after the tachyon relativistic mechanics has been properly developed. They start by showing how to apply the SWP, both in the case of ordinary special relativity and in the case with tachyons. Then they carefully exploit the kinetics of the tachyon exchange between two (ordinary) bodies. Being finally able to tackle the tachyon causality problem, they successively solve the paradoxes of: (i) Tolman-Regge, (ii) Pirani, (iii) Edmonds, and (iv) Bell. Finally, they discuss a further, new paradox associated with the transmission of signals by modulated tachyon beams

  14. Análise florística e estrutura de florestas de várzea no estuário amazônico Floristic analysis and structure of tidal flooded forests in the amazonian estuary

    Directory of Open Access Journals (Sweden)

    Samuel Soares de Almeida

    2004-12-01

    Full Text Available Este trabalho apresenta os resultados de análise fitossociológica e da estrutura, feita em 4 inventários florísticos executados em parcelas de 1 hectare de florestas inundáveis de várzea localizadas na área do estuário e do baixo Amazonas. As florestas de várzea do estuário albergam uma riqueza de espécies relativamente baixa em relação a outras áreas da região como as florestas de terra firme. No entanto a estrutura de tamanho é considerável, com as árvores atingindo elevada biomassa vegetal. Provavelmente isto é devido ao aporte constante de nutrientes através dos sedimentos que viajam milhares de quilômetros de distância desde as nascentes andinas até o delta do rio Amazonas. As florestas inundáveis de várzea são dominadas por poucas espécies, algumas com muitos indivíduos, como o açaí (Euterpe oleracea e o muru-muru (Astrocaryum murumuru, outras com árvores muito grandes como a pitaíca (Swartzia polyphylla, pracuúba (Mora paraensis e a seringueira (Hevea brasiliensis. A ucuúba (Virola surinamensis, uma espécie que apresenta populações ameaçadas pela exploração madeireira, parece apresentar tanto indivíduos grandes como elevada densidade. As florestas de várzea apresentam baixa similaridade entre si, provavelmente decorrente da imensa variação do ambiente de várzea nos rios, paranás, ilhas e lagos, como os efeitos de zonação, altura de inundação, salinidade, velocidade da água, entre outros fatores. Estratégias de seleção de áreas de várzea para conservação devem levar em conta a variação ambiental, o grau de interferência humana e a diversidade local e entre ambientes.This work presents results of the analysis made in four 1-hectare plots of floristic inventory in the flooded forests located in the delta and lower basin of the Amazon river. The flooded forests, so called "várzea" forests, harbor a relatively low species richness in relation to other areas such as "terra firme

  15. Is there a causal relationship between alcohol and HIV? Implications ...

    African Journals Online (AJOL)

    There is now conclusive evidence of a causal linkage between heavy drinking patterns and/or alcohol use disorders and the worsening of the disease course for HIV. However, while alcohol usage is consistently associated with the prevalence and incidence of HIV, further research is needed to substantiate causality in ...

  16. An Information Processing Approach to Children's Causal Reasoning.

    Science.gov (United States)

    Siegler, Robert S.

    This paper questions evidence for the thesis that causal reasoning of older children is more logical than that of younger ones, and describes two experiments which attempted to determine (1) whether there are true developmental differences in causal reasoning, and (2) what explanations for developmental differences can be supported. In the first…

  17. The relative performance of bivariate causality tests in small samples

    NARCIS (Netherlands)

    Bult, J..R.; Leeflang, P.S.H.; Wittink, D.R.

    1997-01-01

    Causality tests have been applied to establish directional effects and to reduce the set of potential predictors, For the latter type of application only bivariate tests can be used, In this study we compare bivariate causality tests. Although the problem addressed is general and could benefit

  18. Child Care Subsidy Use and Child Development: Potential Causal Mechanisms

    Science.gov (United States)

    Hawkinson, Laura E.

    2011-01-01

    Research using an experimental design is needed to provide firm causal evidence on the impacts of child care subsidy use on child development, and on underlying causal mechanisms since subsidies can affect child development only indirectly via changes they cause in children's early experiences. However, before costly experimental research is…

  19. Causal Effect Inference with Deep Latent-Variable Models

    NARCIS (Netherlands)

    Louizos, C; Shalit, U.; Mooij, J.; Sontag, D.; Zemel, R.; Welling, M.

    2017-01-01

    Learning individual-level causal effects from observational data, such as inferring the most effective medication for a specific patient, is a problem of growing importance for policy makers. The most important aspect of inferring causal effects from observational data is the handling of

  20. Optimal relaxed causal sampler using sampled-date system theory

    NARCIS (Netherlands)

    Shekhawat, Hanumant; Meinsma, Gjerrit

    This paper studies the design of an optimal relaxed causal sampler using sampled data system theory. A lifted frequency domain approach is used to obtain the existence conditions and the optimal sampler. A state space formulation of the results is also provided. The resulting optimal relaxed causal

  1. Temporal and Statistical Information in Causal Structure Learning

    Science.gov (United States)

    McCormack, Teresa; Frosch, Caren; Patrick, Fiona; Lagnado, David

    2015-01-01

    Three experiments examined children's and adults' abilities to use statistical and temporal information to distinguish between common cause and causal chain structures. In Experiment 1, participants were provided with conditional probability information and/or temporal information and asked to infer the causal structure of a 3-variable mechanical…

  2. Non-Bayesian Inference: Causal Structure Trumps Correlation

    Science.gov (United States)

    Bes, Benedicte; Sloman, Steven; Lucas, Christopher G.; Raufaste, Eric

    2012-01-01

    The study tests the hypothesis that conditional probability judgments can be influenced by causal links between the target event and the evidence even when the statistical relations among variables are held constant. Three experiments varied the causal structure relating three variables and found that (a) the target event was perceived as more…

  3. Weighting-Based Sensitivity Analysis in Causal Mediation Studies

    Science.gov (United States)

    Hong, Guanglei; Qin, Xu; Yang, Fan

    2018-01-01

    Through a sensitivity analysis, the analyst attempts to determine whether a conclusion of causal inference could be easily reversed by a plausible violation of an identification assumption. Analytic conclusions that are harder to alter by such a violation are expected to add a higher value to scientific knowledge about causality. This article…

  4. Causal inference in biology networks with integrated belief propagation.

    Science.gov (United States)

    Chang, Rui; Karr, Jonathan R; Schadt, Eric E

    2015-01-01

    Inferring causal relationships among molecular and higher order phenotypes is a critical step in elucidating the complexity of living systems. Here we propose a novel method for inferring causality that is no longer constrained by the conditional dependency arguments that limit the ability of statistical causal inference methods to resolve causal relationships within sets of graphical models that are Markov equivalent. Our method utilizes Bayesian belief propagation to infer the responses of perturbation events on molecular traits given a hypothesized graph structure. A distance measure between the inferred response distribution and the observed data is defined to assess the 'fitness' of the hypothesized causal relationships. To test our algorithm, we infer causal relationships within equivalence classes of gene networks in which the form of the functional interactions that are possible are assumed to be nonlinear, given synthetic microarray and RNA sequencing data. We also apply our method to infer causality in real metabolic network with v-structure and feedback loop. We show that our method can recapitulate the causal structure and recover the feedback loop only from steady-state data which conventional method cannot.

  5. On the conceptual distinction of general causality orientations

    DEFF Research Database (Denmark)

    Olesen, Martin Hammershøj

    electronic questionnaires of dispositional personality traits (NEO-FFI) and general causality orientations (GCOS). Proposed separate latent models and alternative shared latent models of the underlying individual differences constructs had been developed in a previous exploratory study (Olesen, Thomsen......, that is general causality orientations can be understood as characteristic adaptations of dispositional traits....

  6. Theories of conduct disorder: a causal modelling analysis

    NARCIS (Netherlands)

    Krol, N.P.C.M.; Morton, J.; Bruyn, E.E.J. De

    2004-01-01

    Background: If a clinician has to make decisions on diagnosis and treatment, he or she is confronted with a variety of causal theories. In order to compare these theories a neutral terminology and notational system is needed. The Causal Modelling framework involving three levels of description –

  7. Financial networks based on Granger causality: A case study

    NARCIS (Netherlands)

    Papana, A.; Kyrtsou, C.; Kugiumtzis, D.; Diks, C.

    Connectivity analysis is performed on a long financial record of 21 international stock indices employing a linear and a nonlinear causality measure, the conditional Granger causality index (CGCI) and the partial mutual information on mixed embedding (PMIME), respectively. Both measures aim to

  8. Causal pathways between substance use disorders and personality pathology

    NARCIS (Netherlands)

    Verheul, R.; van den Brink, W.

    2005-01-01

    A high co-occurrence between personality and substance use disorders suggests causal relationships between these conditions. Most empirical evidence strongly supports causal pathways in which (pathological) personality traits contribute to the development of a substance use disorder (i.e., primary

  9. Nonparametric Identification of Causal Effects under Temporal Dependence

    Science.gov (United States)

    Dafoe, Allan

    2018-01-01

    Social scientists routinely address temporal dependence by adopting a simple technical fix. However, the correct identification strategy for a causal effect depends on causal assumptions. These need to be explicated and justified; almost no studies do so. This article addresses this shortcoming by offering a precise general statement of the…

  10. Causal inference in survival analysis using pseudo-observations

    DEFF Research Database (Denmark)

    Andersen, Per K; Syriopoulou, Elisavet; Parner, Erik T

    2017-01-01

    Causal inference for non-censored response variables, such as binary or quantitative outcomes, is often based on either (1) direct standardization ('G-formula') or (2) inverse probability of treatment assignment weights ('propensity score'). To do causal inference in survival analysis, one needs ...

  11. Thinking Fast and Slow about Causality: Response to Palinkas

    Science.gov (United States)

    Marsh, Jeanne C.

    2014-01-01

    Larry Palinkas advances the developing science of social work by providing an explanation of how social science research methods, both qualitative and quantitative, can improve our capacity to draw casual inferences. Understanding causal relations and making causal inferences--with the promise of being able to predict and control outcomes--is…

  12. Ends, Principles, and Causal Explanation in Educational Justice

    Science.gov (United States)

    Dum, Jenn

    2017-01-01

    Many principles characterize educational justice in terms of the relationship between educational inputs, outputs and distributive standards. Such principles depend upon the "causal pathway view" of education. It is implicit in this view that the causally effective aspects of education can be understood as separate from the normative…

  13. Cause and Event: Supporting Causal Claims through Logistic Models

    Science.gov (United States)

    O'Connell, Ann A.; Gray, DeLeon L.

    2011-01-01

    Efforts to identify and support credible causal claims have received intense interest in the research community, particularly over the past few decades. In this paper, we focus on the use of statistical procedures designed to support causal claims for a treatment or intervention when the response variable of interest is dichotomous. We identify…

  14. A note on mental content in the Causal Theory

    African Journals Online (AJOL)

    A note on mental content in the Causal Theory. JP Smit. Department of Philosophy, Stellenbosch University, Private Bag X1, 7600 Matieland, South Africa. E-mail: jps@sun.ac.za. Kripke's causal theory requires that downstream users of a name must have the intention to use the name in the same way that upstream users ...

  15. Sartre's Contingency of Being and Asouzu's Principle of Causality ...

    African Journals Online (AJOL)

    The position of this work is that all contingent beings have a causal agent. This position is taken as a result of trying to delve into the issue of contingency and causality of being which has been discussed by many philosophers of diverse epochs of philosophy. This work tries to participate in the debate of whether contingent ...

  16. Causal Relationship Between Relative Price Variability and Inflation in Turkey:

    Directory of Open Access Journals (Sweden)

    Nebiye Yamak

    2016-09-01

    Full Text Available This study investigates the causal relationship between inflation and relative price variability in Turkey for the period of January 2003-January 2014, by using panel data. In the study, a Granger (1969 non-causality test in heterogeneous panel data models developed by Dumitrescu and Hurlin (2012 is utilized to determine the causal relations between inflation rate relative price variability. The panel data consists of 4123 observations: 133 time observations and 31 cross-section observations. The results of panel causality test indicate that there is a bidirectional causality between inflation rate and relative price variability by not supporting the imperfection information model of Lucas and the menu cost model of Ball and Mankiw.

  17. Statistical causal inferences and their applications in public health research

    CERN Document Server

    Wu, Pan; Chen, Ding-Geng

    2016-01-01

    This book compiles and presents new developments in statistical causal inference. The accompanying data and computer programs are publicly available so readers may replicate the model development and data analysis presented in each chapter. In this way, methodology is taught so that readers may implement it directly. The book brings together experts engaged in causal inference research to present and discuss recent issues in causal inference methodological development. This is also a timely look at causal inference applied to scenarios that range from clinical trials to mediation and public health research more broadly. In an academic setting, this book will serve as a reference and guide to a course in causal inference at the graduate level (Master's or Doctorate). It is particularly relevant for students pursuing degrees in Statistics, Biostatistics and Computational Biology. Researchers and data analysts in public health and biomedical research will also find this book to be an important reference.

  18. Causal Relationship between Construction Production and GDP in Turkey

    Directory of Open Access Journals (Sweden)

    Hakkı Kutay Bolkol

    2015-12-01

    Full Text Available This study empirically investigates the causal relationship between construction production and GDP for Turkey during 2005Q1-2013Q4 period. Because it is found that, there is no cointegration which means there is no long run relationship between variables, VAR Granger Causality Method is used to test the causality in short run. The findings reveal that, the causality runs from GDP to Building Production and Building Production to Non-Building Production (i.e. bidirectional relationship. Findings of this paper suggest that, because there is no long run relationship between Construction Production (Building and Non-Building and GDP and also in short run the causality runs from GDP to Construction Production, the growth strategy based on mainly Construction Sector growth is not a good idea for Turkey.

  19. Causal Relationship between Construction Production and GDP in Turkey

    Directory of Open Access Journals (Sweden)

    Hakkı Kutay Bolkol

    2015-09-01

    Full Text Available This study empirically investigates the causal relationship between construction production and GDP for Turkey during 2005Q1-2013Q4 period. Because it is found that, there is no cointegration which means there is no long run relationship between variables, VAR Granger Causality Method is used to test the causality in short run. The findings reveal that, the causality runs from GDP to Building Production and Building Production to Non-Building Production (i.e. bidirectional relationship. Findings of this paper suggest that, because there is no long run relationship between Construction Production (Building and Non-Building and GDP and also in short run the causality runs from GDP to Construction Production, the growth strategy based on mainly Construction Sector growth is not a good idea for Turkey.

  20. Respuesta de la composición florística y la diversidad biológica de pastizales a las estrategias de manejo en una dehesa de la Sierra de Guadarrama, Madrid

    OpenAIRE

    Martínez, T.; Urquia, J.; Tejerina, J.I.; Miguel, J.M. de

    2012-01-01

    Ponencia presentada a la 51 Reunión Científica de la SEEP celebrada en la Escuela Superior de Ingenieros Agrónomos de la Universidad Pública de Navarra entre el 14 y el 18 de mayo de 2012. Este estudio tipifica y caracteriza las comunidades de pastizal en función de su composición florística, riqueza y diversidad biológica en un sistema silvopastoral de dehesa situado en la Sierra de Guadarrama (Finca de Riosequillo, Buitrago de Lozoya, Madrid). Se identifican las tendencias principales de...

  1. Beyond Markov: Accounting for independence violations in causal reasoning.

    Science.gov (United States)

    Rehder, Bob

    2018-06-01

    Although many theories of causal cognition are based on causal graphical models, a key property of such models-the independence relations stipulated by the Markov condition-is routinely violated by human reasoners. This article presents three new accounts of those independence violations, accounts that share the assumption that people's understanding of the correlational structure of data generated from a causal graph differs from that stipulated by causal graphical model framework. To distinguish these models, experiments assessed how people reason with causal graphs that are larger than those tested in previous studies. A traditional common cause network (Y 1 ←X→Y 2 ) was extended so that the effects themselves had effects (Z 1 ←Y 1 ←X→Y 2 →Z 2 ). A traditional common effect network (Y 1 →X←Y 2 ) was extended so that the causes themselves had causes (Z 1 →Y 1 →X←Y 2 ←Z 2 ). Subjects' inferences were most consistent with the beta-Q model in which consistent states of the world-those in which variables are either mostly all present or mostly all absent-are viewed as more probable than stipulated by the causal graphical model framework. Substantial variability in subjects' inferences was also observed, with the result that substantial minorities of subjects were best fit by one of the other models (the dual prototype or a leaky gate models). The discrepancy between normative and human causal cognition stipulated by these models is foundational in the sense that they locate the error not in people's causal reasoning but rather in their causal representations. As a result, they are applicable to any cognitive theory grounded in causal graphical models, including theories of analogy, learning, explanation, categorization, decision-making, and counterfactual reasoning. Preliminary evidence that independence violations indeed generalize to other judgment types is presented. Copyright © 2018 Elsevier Inc. All rights reserved.

  2. Rendimento e qualidade de sementes de arroz irrigado em função da adubação com boro

    OpenAIRE

    LEITE, Ricardo Figueiredo Cavalheiro

    2008-01-01

    O boro é um nutriente essencial para as plantas. Suas funções estão envolvidas com o crescimento celular e o desenvolvimento da flor. Na floração, a deficiência do micronutriente reduz a macho-fertilidade em função do prejuízo à microesporogênese e ao crescimento do tubo polínico. Neste trabalho, objetivou-se definir as fases de maior sensibilidade da cultura, com o intuito de identificar épocas apropriadas para a aplicação de tratamentos corretivos de boro. A aplicação do boro, na forma de b...

  3. Rendimento e qualidade de sementes de arroz irrigado em função da adubação com boro

    OpenAIRE

    Leite, Ricardo Figueiredo Cavalheiro; Schuch, Luis Osmar Braga; Amaral, Ademir dos Santos; Tavares, Lizandro Ciciliano

    2011-01-01

    O boro é um nutriente essencial para as plantas. Suas funções estão envolvidas com o crescimento celular e o desenvolvimento da flor. Na fase reprodutiva, a deficiência do micronutriente reduz a macho-fertilidade em função do prejuízo à microesporogênese e ao crescimento posterior do tubo polínico. Neste trabalho, objetivou-se avaliar o efeito da aplicação de boro, sobre as características agronômicas e a qualidade fisiológica das sementes de arroz produzidas. A aplicação do boro, na forma de...

  4. Aspectos fitossociológicos de um fragmento da floresta natural de Astronium balansae engl., no município de Bossoroca, RS

    Directory of Open Access Journals (Sweden)

    Boligon Alexandra Augusti

    2005-01-01

    Full Text Available Este estudo objetivou conhecer a composição florística e a estrutura fitossociológica de um fragmento da Floresta Natural de Astronium balansae Engl., no município de Bossoroca, RS, Brasil. Foram demarcadas 7 unidades amostrais de 10x100m (1000m2 onde observou-se a ocorrência de 476 indivíduos com Circunferência à Altura do Peito (CAP = 30cm, distribuídos em 35 espécies e 25 famílias. As espécies mais características e importantes da floresta foram Astronium balansae, Myrcianthes pungens, Patagonula americana, Eugenia uniflora e Parapiptadenia rigida. As famílias Myrtaceae, Meliaceae e Euphorbiaceae foram as mais representativas do fragmento florestal estudado. O valor do Índice de diversidade de Shannon foi 3.

  5. Simplifying Causal Complexity: How Interactions between Modes of Causal Induction and Information Availability Lead to Heuristic-Driven Reasoning

    Science.gov (United States)

    Grotzer, Tina A.; Tutwiler, M. Shane

    2014-01-01

    This article considers a set of well-researched default assumptions that people make in reasoning about complex causality and argues that, in part, they result from the forms of causal induction that we engage in and the type of information available in complex environments. It considers how information often falls outside our attentional frame…

  6. Predicting Causal Relationships from Biological Data: Applying Automated Causal Discovery on Mass Cytometry Data of Human Immune Cells

    KAUST Repository

    Triantafillou, Sofia; Lagani, Vincenzo; Heinze-Deml, Christina; Schmidt, Angelika; Tegner, Jesper; Tsamardinos, Ioannis

    2017-01-01

    Learning the causal relationships that define a molecular system allows us to predict how the system will respond to different interventions. Distinguishing causality from mere association typically requires randomized experiments. Methods for automated  causal discovery from limited experiments exist, but have so far rarely been tested in systems biology applications. In this work, we apply state-of-the art causal discovery methods on a large collection of public mass cytometry data sets, measuring intra-cellular signaling proteins of the human immune system and their response to several perturbations. We show how different experimental conditions can be used to facilitate causal discovery, and apply two fundamental methods that produce context-specific causal predictions. Causal predictions were reproducible across independent data sets from two different studies, but often disagree with the KEGG pathway databases. Within this context, we discuss the caveats we need to overcome for automated causal discovery to become a part of the routine data analysis in systems biology.

  7. Causal beliefs about depression in different cultural groups – What do cognitive psychological theories of causal learning and reasoning predict?

    Directory of Open Access Journals (Sweden)

    York eHagmayer

    2014-11-01

    Full Text Available Cognitive psychological research focusses on causal learning and reasoning while cognitive anthropological and social science research tend to focus on systems of beliefs. Our aim was to explore how these two types of research can inform each other. Cognitive psychological theories (causal model theory and causal Bayes nets were used to derive predictions for systems of causal beliefs. These predictions were then applied to lay theories of depression as a specific test case. A systematic literature review on causal beliefs about depression was conducted, including original, quantitative research. Thirty-six studies investigating 13 non-Western and 32 Western cultural groups were analysed by classifying assumed causes and preferred forms of treatment into common categories. Relations between beliefs and treatment preferences were assessed. Substantial agreement between cultural groups was found with respect to the impact of observable causes. Stress was generally rated as most important. Less agreement resulted for hidden, especially supernatural causes. Causal beliefs were clearly related to treatment preferences in Western groups, while evidence was mostly lacking for non-Western groups. Overall predictions were supported, but there were considerable methodological limitations. Pointers to future research, which may combine studies on causal beliefs with experimental paradigms on causal reasoning, are given.

  8. Predicting Causal Relationships from Biological Data: Applying Automated Causal Discovery on Mass Cytometry Data of Human Immune Cells

    KAUST Repository

    Triantafillou, Sofia

    2017-09-29

    Learning the causal relationships that define a molecular system allows us to predict how the system will respond to different interventions. Distinguishing causality from mere association typically requires randomized experiments. Methods for automated  causal discovery from limited experiments exist, but have so far rarely been tested in systems biology applications. In this work, we apply state-of-the art causal discovery methods on a large collection of public mass cytometry data sets, measuring intra-cellular signaling proteins of the human immune system and their response to several perturbations. We show how different experimental conditions can be used to facilitate causal discovery, and apply two fundamental methods that produce context-specific causal predictions. Causal predictions were reproducible across independent data sets from two different studies, but often disagree with the KEGG pathway databases. Within this context, we discuss the caveats we need to overcome for automated causal discovery to become a part of the routine data analysis in systems biology.

  9. Causality and subjectivity in discourse : The meaning and use of causal connectives in spontaneous conversation, chat interactions and written text

    NARCIS (Netherlands)

    Sanders, T.J.M.|info:eu-repo/dai/nl/075243911; Spooren, W.P.M.S.

    Many languages of the world have connectives to express causal relations at the discourse level. Often, language users systematically prefer one lexical item (because) over another (even highly similar) one (since) to express a causal relationship. Such choices provide a window on speakers'

  10. Averaged null energy condition from causality

    Science.gov (United States)

    Hartman, Thomas; Kundu, Sandipan; Tajdini, Amirhossein

    2017-07-01

    Unitary, Lorentz-invariant quantum field theories in flat spacetime obey mi-crocausality: commutators vanish at spacelike separation. For interacting theories in more than two dimensions, we show that this implies that the averaged null energy, ∫ duT uu , must be non-negative. This non-local operator appears in the operator product expansion of local operators in the lightcone limit, and therefore contributes to n-point functions. We derive a sum rule that isolates this contribution and is manifestly positive. The argument also applies to certain higher spin operators other than the stress tensor, generating an infinite family of new constraints of the form ∫ duX uuu··· u ≥ 0. These lead to new inequalities for the coupling constants of spinning operators in conformal field theory, which include as special cases (but are generally stronger than) the existing constraints from the lightcone bootstrap, deep inelastic scattering, conformal collider methods, and relative entropy. We also comment on the relation to the recent derivation of the averaged null energy condition from relative entropy, and suggest a more general connection between causality and information-theoretic inequalities in QFT.

  11. Reconstructing Causal Biological Networks through Active Learning.

    Directory of Open Access Journals (Sweden)

    Hyunghoon Cho

    Full Text Available Reverse-engineering of biological networks is a central problem in systems biology. The use of intervention data, such as gene knockouts or knockdowns, is typically used for teasing apart causal relationships among genes. Under time or resource constraints, one needs to carefully choose which intervention experiments to carry out. Previous approaches for selecting most informative interventions have largely been focused on discrete Bayesian networks. However, continuous Bayesian networks are of great practical interest, especially in the study of complex biological systems and their quantitative properties. In this work, we present an efficient, information-theoretic active learning algorithm for Gaussian Bayesian networks (GBNs, which serve as important models for gene regulatory networks. In addition to providing linear-algebraic insights unique to GBNs, leading to significant runtime improvements, we demonstrate the effectiveness of our method on data simulated with GBNs and the DREAM4 network inference challenge data sets. Our method generally leads to faster recovery of underlying network structure and faster convergence to final distribution of confidence scores over candidate graph structures using the full data, in comparison to random selection of intervention experiments.

  12. Causality and local determinism versus quantum nonlocality

    International Nuclear Information System (INIS)

    Kupczynski, M

    2014-01-01

    The entanglement and the violation of Bell and CHSH inequalities in spin polarization correlation experiments (SPCE) is considered to be one of the biggest mysteries of Nature and is called quantum nonlocality. In this paper we show once again that this conclusion is based on imprecise terminology and on the lack of understanding of probabilistic models used in various proofs of Bell and CHSH theorems. These models are inconsistent with experimental protocols used in SPCE. This is the only reason why Bell and CHSH inequalities are violated. A probabilistic non-signalling description of SPCE, consistent with quantum predictions, is possible and it depends explicitly on the context of each experiment. It is also deterministic in the sense that the outcome is determined by supplementary local parameters describing both physical signals and measuring instruments. The existence of such description gives additional arguments that quantum theory is emergent from some more detailed theory respecting causality and local determinism. If quantum theory is emergent then there exist perhaps some fine structures in time-series of experimental data which were not predicted by quantum theory. In this paper we explain how a systematic search for such fine structures can be done. If such reproducible fine structures were found it would show that quantum theory is not predictably complete, which would be a major discovery.

  13. From causal dynamical triangulations to astronomical observations

    Science.gov (United States)

    Mielczarek, Jakub

    2017-09-01

    This letter discusses phenomenological aspects of dimensional reduction predicted by the Causal Dynamical Triangulations (CDT) approach to quantum gravity. The deformed form of the dispersion relation for the fields defined on the CDT space-time is reconstructed. Using the Fermi satellite observations of the GRB 090510 source we find that the energy scale of the dimensional reduction is E* > 0.7 \\sqrt{4-d\\text{UV}} \\cdot 1010 \\text{GeV} at (95% CL), where d\\text{UV} is the value of the spectral dimension in the UV limit. By applying the deformed dispersion relation to the cosmological perturbations it is shown that, for a scenario when the primordial perturbations are formed in the UV region, the scalar power spectrum PS \\propto kn_S-1 , where n_S-1≈ \\frac{3 r (d\\text{UV}-2)}{(d\\text{UV}-1)r-48} . Here, r is the tensor-to-scalar ratio. We find that within the considered model, the predicted from CDT deviation from the scale invariance (n_S=1) is in contradiction with the up to date Planck and BICEP2.

  14. Hypothyroidism and Hyponatremia: Rather Coincidence Than Causality.

    Science.gov (United States)

    Wolf, Peter; Beiglböck, Hannes; Smaijs, Sabina; Wrba, Thomas; Rasoul-Rockenschaub, Susanne; Marculescu, Rodrig; Gessl, Alois; Luger, Anton; Winhofer, Yvonne; Krebs, Michael

    2017-05-01

    Hypothyroidism is referred to be a rare but possible cause of hyponatremia. However, there is only poor evidence supporting this association. Since hyponatremia and hypothyroidism are both common conditions themselves, co-occurrence does not have to be causal. To address a potential relationship, a retrospective analysis of data from the Division of Endocrinology of the Medical University of Vienna from April 2004 to February 2016 was performed. A total of 8053 hypothyroid patients (48 ± 18 years of age; 71% female) with thyrotropin >4.0 μIU/mL and available blood tests for free thyroxine and sodium (Na + ) within maximal ± seven days were included and screened for hyponatremia. Patients' records were searched for concomitant disease and medication when Na + concentration was causes of hyponatremia in 442/448 (98.88%) patients (i.e., side effects of medication, concomitant underlying disease, or other endocrine disorders). This distribution did not differ between patients suffering from clinical or subclinical hypothyroidism. No case of clinically relevant hyponatremia (Na + hypothyroidism. There was a very weak but statistically significant trend toward a positive association between thyroid function and serum Na + levels (Na + /thyrotropin: R = 0.022, p = 0.046; Na + /free thyroxine: R = -0.047, p hypothyroid patients with moderate to severe hyponatremia often have other potential explanations for their low serum Na + concentrations in routine care.

  15. Dynamic Causal Models and Autopoietic Systems

    Directory of Open Access Journals (Sweden)

    OLIVIER DAVID

    2007-01-01

    Full Text Available Dynamic Causal Modelling (DCM and the theory of autopoietic systems are two important conceptual frameworks. In this review, we suggest that they can be combined to answer important questions about self-organising systems like the brain. DCM has been developed recently by the neuroimaging community to explain, using biophysical models, the non-invasive brain imaging data are caused by neural processes. It allows one to ask mechanistic questions about the implementation of cerebral processes. In DCM the parameters of biophysical models are estimated from measured data and the evidence for each model is evaluated. This enables one to test different functional hypotheses (i.e., models for a given data set. Autopoiesis and related formal theories of biological systems as autonomous machines represent a body of concepts with many successful applications. However, autopoiesis has remained largely theoretical and has not penetrated the empiricism of cognitive neuroscience. In this review, we try to show the connections that exist between DCM and autopoiesis. In particular, we propose a simple modification to standard formulations of DCM that includes autonomous processes. The idea is to exploit the machinery of the system identification of DCMs in neuroimaging to test the face validity of the autopoietic theory applied to neural subsystems. We illustrate the theoretical concepts and their implications for interpreting electroencephalographic signals acquired during amygdala stimulation in an epileptic patient. The results suggest that DCM represents a relevant biophysical approach to brain functional organisation, with a potential that is yet to be fully evaluated

  16. Physics Without Causality — Theory and Evidence

    Science.gov (United States)

    Shoup, Richard

    2006-10-01

    The principle of cause and effect is deeply rooted in human experience, so much so that it is routinely and tacitly assumed throughout science, even by scientists working in areas where time symmetry is theoretically ingrained, as it is in both classical and quantum physics. Experiments are said to cause their results, not the other way around. In this informal paper, we argue that this assumption should be replaced with a more general notion of mutual influence — bi-directional relations or constraints on joint values of two or more variables. From an analysis based on quantum entropy, it is proposed that quantum measurement is a unitary three-interaction, with no collapse, no fundamental randomness, and no barrier to backward influence. Experimental results suggesting retrocausality are seen frequently in well-controlled laboratory experiments in parapsychology and elsewhere, especially where a random element is included. Certain common characteristics of these experiments give the appearance of contradicting well-established physical laws, thus providing an opportunity for deeper understanding and important clues that must be addressed by any explanatory theory. We discuss how retrocausal effects and other anomalous phenomena can be explained without major injury to existing physical theory. A modified quantum formalism can give new insights into the nature of quantum measurement, randomness, entanglement, causality, and time.

  17. Dilepton production in schematic causal viscous hydrodynamics

    International Nuclear Information System (INIS)

    Song, Taesoo; Han, Kyong Chol; Ko, Che Ming

    2011-01-01

    Assuming that in the hot dense matter produced in relativistic heavy-ion collisions, the energy density, entropy density, and pressure as well as the azimuthal and space-time rapidity components of the shear tensor are uniform in the direction transversal to the reaction plane, we derive a set of schematic equations from the Isreal-Stewart causal viscous hydrodynamics. These equations are then used to describe the evolution dynamics of relativistic heavy-ion collisions by taking the shear viscosity to entropy density ratio of 1/4π for the initial quark-gluon plasma (QGP) phase and of 10 times this value for the later hadron-gas (HG) phase. Using the production rate evaluated with particle distributions that take into account the viscous effect, we study dilepton production in central heavy-ion collisions. Compared with results from the ideal hydrodynamics, we find that although the dilepton invariant mass spectra from the two approaches are similar, the transverse momentum spectra are significantly enhanced at high transverse momenta by the viscous effect. We also study the transverse momentum dependence of dileptons produced from QGP for a fixed transverse mass, which is essentially absent in the ideal hydrodynamics, and find that this so-called transverse mass scaling is violated in the viscous hydrodynamics, particularly at high transverse momenta.

  18. The Causal Factors Associated with the Loving

    Directory of Open Access Journals (Sweden)

    Seyed Taghi Heydari

    2015-10-01

    Full Text Available Background: Families with disabled children need more psycho-social considerations. Motherhood care of the children with multiple disabilities is difficult. Due to its importance, the aim of this study was to investigate the causal factors affecting loving care of mothers of children with multiple disabilities. Methods: The study used a cross-sectional method in which 75 mothers of exceptional children with multiple disabilities (physical and mental in elementary schools in Shiraz, Iran. The data were collected through questionnaires which, besides demographical factors, evaluated the relationship between mothers’ loving care of children with multiple disabilities and four other variables including purpose in life, life satisfaction, religious attitude, and sense of coherence. Mann-Whitney U was used for comparison between mothers’ loving care and other variables. Results: Results revealed that demographic variables did not have a significant relationship with loving care. In the case of social variables, there was a significant relationship between mothers’ loving care and purpose in life (P<0.001, religious attitude (P<0.001, and life satisfaction (P=0.01. Conclusion: Motherhood care of disabled children is a unique phenomenon which is due to attachment of mother-child situation. Nevertheless, these mothers are vulnerable and marginalized people who need more attention and social supports provided by related governmental institutions and also NGOs actors.

  19. Quantum erasure with causally disconnected choice.

    Science.gov (United States)

    Ma, Xiao-Song; Kofler, Johannes; Qarry, Angie; Tetik, Nuray; Scheidl, Thomas; Ursin, Rupert; Ramelow, Sven; Herbst, Thomas; Ratschbacher, Lothar; Fedrizzi, Alessandro; Jennewein, Thomas; Zeilinger, Anton

    2013-01-22

    The counterintuitive features of quantum physics challenge many common-sense assumptions. In an interferometric quantum eraser experiment, one can actively choose whether or not to erase which-path information (a particle feature) of one quantum system and thus observe its wave feature via interference or not by performing a suitable measurement on a distant quantum system entangled with it. In all experiments performed to date, this choice took place either in the past or, in some delayed-choice arrangements, in the future of the interference. Thus, in principle, physical communications between choice and interference were not excluded. Here, we report a quantum eraser experiment in which, by enforcing Einstein locality, no such communication is possible. This is achieved by independent active choices, which are space-like separated from the interference. Our setup employs hybrid path-polarization entangled photon pairs, which are distributed over an optical fiber link of 55 m in one experiment, or over a free-space link of 144 km in another. No naive realistic picture is compatible with our results because whether a quantum could be seen as showing particle- or wave-like behavior would depend on a causally disconnected choice. It is therefore suggestive to abandon such pictures altogether.

  20. Quantum Steering Beyond Instrumental Causal Networks

    Science.gov (United States)

    Nery, R. V.; Taddei, M. M.; Chaves, R.; Aolita, L.

    2018-04-01

    We theoretically predict, and experimentally verify with entangled photons, that outcome communication is not enough for hidden-state models to reproduce quantum steering. Hidden-state models with outcome communication correspond, in turn, to the well-known instrumental processes of causal inference but in the one-sided device-independent scenario of one black-box measurement device and one well-characterized quantum apparatus. We introduce one-sided device-independent instrumental inequalities to test against these models, with the appealing feature of detecting entanglement even when communication of the black box's measurement outcome is allowed. We find that, remarkably, these inequalities can also be violated solely with steering, i.e., without outcome communication. In fact, an efficiently computable formal quantifier—the robustness of noninstrumentality—naturally arises, and we prove that steering alone is enough to maximize it. Our findings imply that quantum theory admits a stronger form of steering than known until now, with fundamental as well as practical potential implications.