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  1. Estimativa do fluxo de calor latente pelo balanço de energia em cultivo protegido de pimentão Estimate of the latent heat flux by the energy balance in protected cultivation of sweet pepper

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    Antonio Ribeiro da Cunha

    2002-06-01

    Full Text Available O objetivo deste trabalho foi caracterizar e relacionar a radiação líquida com o calor latente equivalente, em mm de água, nos cultivos protegido e de campo, na cultura de pimentão. O experimento foi feito em Botucatu, SP. A estimativa do fluxo de calor latente foi feita pelo método do balanço de energia, por meio da razão de Bowen. Foram feitas medidas instantâneas da radiação líquida (Rn, dos fluxos convectivos de calor latente (LE e sensível (H, do fluxo de calor no solo (G, e dos gradientes psicrométricos sobre a cultura. O cultivo protegido, apesar de receber menor quantidade de radiação solar global, foi mais eficiente na conversão da radiação líquida disponível em matéria seca total e na produtividade de frutos. No balanço de energia, o cultivo protegido apresentou razões G/Rn e LE/Rn inferiores e H/Rn superior, com um fluxo de calor latente, equivalente em milímetros, 45,43% menor que no cultivo no campo. Apresentou, ainda, menor quantidade de radiação líquida disponível e menores perdas de energia, mostrando-se mais eficiente no uso da água.The aim of this work was to characterize and bring into relationship the net radiation with the latent heat flux equivalent to water mm, in sweet pepper crops in the field and in protected cultivation. The estimate of latent heat flux was made by the energy balance method through the Bowen ratio. Instantaneous measures were made of net radiation (Rn, sensitive (H and latent (LE heat fluxes, heat flux into the soil (G, and of psychrometers gradients in the crop canopy. In protected cultivation, the conversion of the available net radiation in total dry matter and fruit productivity was more efficient than in the field, in spite of lower amounts of global solar radiation received by the crop. Ratios of G/Rn and LE/Rn were lower, and that of H/Rn was higher in protected cultivation, with an equivalent latent heat flux in millimeters, 45.43% lower than that determined in the

  2. Latent heat loss of Holstein cows in a tropical environment: a prediction model Perda de calor latente em vacas Holandesas em ambiente tropical: um modelo de predição

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    Alex Sandro Campos Maia

    2008-10-01

    Full Text Available Nine lactating Holstein cows with average 526 ± 5 kg of BW, five predominantly black and four predominantly white, bred in a tropical region and managed in open pasture were observed to measure cutaneous and respiratory evaporation rates under different environmental conditions. Cows were separated in three weight class: 1 (500 kg. Latent heat loss from cutaneous surface was measured using a ventilated capsule; evaporation in the respiratory system was measured using a facial mask. The results showed that heaviest cows (2 and 3 classes presented the least evaporation rates. When air temperature increased from 10 to 36ºC the relative humidity decreased from 90 to 30%. In these conditions the heat loss by respiratory evaporation increased from 5 to 57 Wm-2, while the heat loss by cutaneous evaporation increased from 30 to 350 Wm-2. The results confirm that latent heat loss was the main way of thermal energy elimination under high air temperatures (>30ºC; cutaneous evaporation was the main mechanism of heat loss, responding for about 85% of the heat loss. A model was presented for the prediction of the latent heat loss that was based on physiological and environmental variables and could be used to estimate the contribution of evaporation to thermoregulation; a second, based on air temperature only, should be used to make a simple characterization of the evaporation process.Nove vacas Holandesas lactantes com 526 ± 5 kg de peso corporal (cinco predominantemente pretas e quatro predominantemente brancas, criadas em região tropical e manejadas em pastagens, foram observadas com os objetivos de determinar simultaneamente as taxas de evaporação cutânea e respiratória em ambiente tropical e desenvolver modelos de predição. Para a medição da perda de calor latente pela superfície corporal, utilizou-se uma cápsula ventilada e, para a perda por respiração, utilizou-se uma máscara facial. Os resultados mostraram que as vacas que tinham

  3. Papel dos fluxos de calor latente e sensível em superfície associado a um caso de ciclogênese na Costa Leste da América do Sul Role of surface latent and sensible heat fluxes associated to a South America East Coast cyclogenesis case

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    Everson Dal Piva

    2008-12-01

    Full Text Available Neste estudo foram realizados experimentos numéricos com um modelo meteorológico regional a fim de verificar o impacto dos Fluxos de Calor Latente (FCL e Calor Sensível (FCS em superfície no desenvolvimento de um ciclone intenso ocorrido sobre a costa leste da região sudeste da América do Sul, entre os dias 24 e 26 de julho de 1998. A taxa de intensificação do ciclone foi reduzida em 6 hPa/24 h no experimento em que os FCL e FCS estavam ausentes. Verificou-se que a ausência do FCL apresentou maior impacto do que a ausência do FCS, fazendo com que a taxa de intensificação fosse reduzida em 6 hPa/24 h para o experimento sem FCL e permanecesse inalterada sem FCS, mas neste último a isóbara de menor valor no centro do ciclone ocupou uma área menor. A ausência dos FCL e FCS em superfície gerou uma camada mais seca e mais fria próxima à superfície oceânica, reduzindo a instabilidade potencial do ambiente e diminuindo a intensificação do ciclone. Concluiu-se, portanto que os FCL e FCS em superfície foram importantes antes da fase de mais rápido desenvolvimento do ciclone, agindo no sentido de preparar o ambiente para uma ciclogênese mais intensa, através do fornecimento de energia e umidade para a baixa troposfera. Na fase de mais rápido desenvolvimento, a energia e a umidade disponíveis nas camadas mais baixas da atmosfera (inseridos na fase anterior também foram importantes, permitindo ao ciclone se desenvolver mais intensamente do que ocorreria em um ambiente mais seco e menos instável termicamente.Numeric experiments were run with meteorological regional model with the purpose to verify the impact of both latent and sensible surface heat fluxes (FCL and FCS, respectively during the development of an intense east cost cyclone over southeastern region of South America from 24 to 26 July, 1998. The intensification rate of the cyclone was reduced by 6 hPa/24 h in the experiment where the FCL and FCS were absents. It was

  4. Estudo numérico-experimental da solidificação de material de mudança de fase em torno de tubos com aletas radiais para aplicações em armazenadores de calor latente

    OpenAIRE

    Priscila Dias da Silva

    2016-01-01

    O armazenamento térmico é utilizado como um meio de aproveitamento da energia disponível em um determinado período de tempo, que poderá ser utilizada posteriormente. Este deslocamento de energia no tempo é importante, pois possibilita o aumento da eficiência energética do sistema e promove uma utilização mais adequada da energia disponível em algum momento do processo e que poderia ser desperdiçada se não fosse armazenada. Na literatura são escassos os trabalhos em relação a armazenadores de ...

  5. Cinética da transferência de calor em materiais com mudança de fase

    OpenAIRE

    Vitorino, Nuno Miguel Dias

    2013-01-01

    É extensa a bibliografia dedicada a potenciais aplicações de materiais com mudança de fase na regulação térmica e no armazenamento de calor ou de frio. No entanto, a baixa condutividade térmica impõe limitações numa grande diversidade de aplicações com exigências críticas em termos de tempo de resposta curto ou com requisitos de elevada potência em ciclos de carga/descarga de calor latente. Foram desenvolvidos códigos numéricos no sentido de obter soluções precisas para descrever a c...

  6. Uso de transdutores de fluxo de calor no estudo da transferência de calor em alimentos embalados

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    Carciofi B.

    2002-01-01

    Full Text Available A densidade de fluxo de calor que atravessa uma superfície é classicamente determinada mediante a medição das temperaturas apropriadas e da aplicação da Lei de Fourier. Uma alternativa a esse procedimento é a utilização de transdutores de fluxo de calor, os quais geram um sinal elétrico proporcional ao fluxo térmico que os atravessa. Neste trabalho, processos de aquecimento e de resfriamento de alimentos foram estudados em laboratório, utilizando-se um recipiente de vidro cilíndrico para simular uma embalagem. Dois transdutores de fluxo de calor a gradiente tangencial foram previamente instalados no recipiente, revestindo completamente a superfície lateral do mesmo. O recipiente contendo a amostra foi inserido em banho de água circulante à temperatura constante. Os sinais fornecidos pelos transdutores e por termopares inseridos no interior do recipiente foram registrados por um sistema de aquisição de dados computadorizado. Os resultados obtidos com o uso dos transdutores foram comparados com aqueles obtidos através de balanços de energia realizados a partir dos dados experimentais de evolução temporal das temperaturas da amostra junto à superfície interna da embalagem e no centro da mesma. A comparação mostrou que os transdutores de fluxo de calor a gradiente tangencial puderam determinar os fluxos de calor, com tempo de resposta característico dos termopares. Os resultados apresentados mostraram a viabilidade de utilização desses fluxímetros no estudo não destrutivo e não invasivo dos processos de aquecimento e de resfriamento de alimentos, fornecendo informações complementares àquelas obtidas pelo uso de termopares instalados no interior da embalagem.

  7. Herdabilidade da necessidade de calor para a antese e brotação em pessegueiro

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    Citadin Idemir

    2003-01-01

    Full Text Available A herdabilidade da necessidade de calor para antese e brotação em pessegueiro [Prunus persica (L. Batsch] foi estudada em ramos de 16 cultivares e seleções de baixa, média e alta necessidade de calor e 11 progênies oriundas de hibridações entre elas. Os ramos foram submetidos, previamente, a 2 ºC por 500 horas para satisfazer a necessidade de frio. O valor estimado da herdabilidade média para a necessidade de calor em gemas florais foi de 45% e 57%, em 1999 e 2000, respectivamente. Para gemas vegetativas, o valor estimado foi de 30%, em 1999. 'BR-1', 'Barbosa', 'Chula', 'Chinoca' e 'Eldorado' transmitem melhor o caráter necessidade de calor para as progênies do que os demais genótipos estudados. Os registros observados suportam um modelo de herança quantitativa com genes de maior efeito para menor necessidade de calor. A seleção de indivíduos com maior necessidade de calor para floração tende a retardar a floração sem, contudo, retardar com a mesma intensidade a época de brotação.

  8. Humedad de equilibrio y calor latente de vaporización del ajonjolí. Sésamun indicum L.

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    Julio E. Ospina M.

    2011-06-01

    Full Text Available El ajonjolí (Sésamun indicum L., es una oleaginosa originaria de África y cultivada en las regiones tropicales y subtropicales de Asia y América. A los 110 días de sembrada se cosecha la semilla la cual se utiliza como materia prima especialmente en la industria de grasas y aceites comestibles. Actualmente se pierden en Colombia, un alto porcentaje de semillas durante el proceso de secado natura en el campo. Debido a la falta de información técnica, científica en secado y almacenamiento del grana de ajonjolí se procedió a estudiar la metodología para determinar, el contenido de humedad por el método de la estufa, las curvas y modelo para cuantificar la humedad de equilibrio y el calor latente de vaporización.

  9. Transferência de calor e controle de temperatura em tubos capilares utilizados em eletroforese capilar

    OpenAIRE

    Rodrigo Danieli

    2005-01-01

    Este trabalho tem por objetivo estudar a transferência de calor em tubos capilares cilíndricos utilizados na técnica de separação de moléculas denominada Eletroforese Capilar. Esta técnica é usada, por exemplo, na análise de biomoléculas e no sequenciamento de DNA, onde o controle da temperatura está diretamente ligado ao desempenho destes métodos e à qualidade dos resultados. Para empregar esta técnica, tensões elétricas da ordem de 20 kV são aplicadas entre as extremidades dos tubos capilar...

  10. Hydrometeor and latent heat profiles of tropical cyclones Conson, Ivan and Catarina using PR/TRMM data Perfis de hidrometeoros e de calor latente dos ciclones tropicais Conson, Ivan e Catarina usando dados do PR/TRMM

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    Marcelo Barbio Rosa

    2010-06-01

    Full Text Available ABSTRACT Microphysical and thermodynamical features of two tropical systems, namely Hurricane Ivan and Typhoon Conson, and one sub-tropical, Catarina, have been analyzed based on space-born radar PR measurements available on the TRMM satellite. The procedure to classify the reflectivity profiles followed the Heymsfield et al (2000 and Steiner et al (1995 methodologies. The water and ice content have been calculated using a relationship obtained with data of the surface SPOL radar and PR in Rondonia State in Brazil. The diabatic heating rate due to latent heat release has been estimated using the methodology developed by Tao et al (1990. A more detailed analysis has been performed for Hurricane Catarina, the first of its kind in South Atlantic. High water content mean value has been found in Conson and Ivan at low levels and close to their centers. Results indicate that hurricane Catarina was shallower than the other two systems, with less water and the water was concentrated closer to its center. The mean ice content in Catarina was about 0.05 g kg-1 while in Conson it was 0.06 g kg-1 and in Ivan 0.08 g kg-1. Conson and Ivan had water content up to 0.3 g kg-1 above the 0ºC layer, while Catarina had less than 0.15 g kg-1. The latent heat released by Catarina showed to be very similar to the other two systems, except in the regions closer to the center.No presente trabalho foram analisados as características microfísicas e termodinâmicas de dois sistemas tropicais, o Furacão Ivan e o Tufão Conson, e um sub-tropical, Catarina, a partir de medições feitas com o radar PR a bordo do satélite TRMM. Na análise, os perfis de refletividade foram classificados conforme as técnicas de Heymsfield et al (2000 e Steiner et al (1995 e em seguida foram calculados os conteúdos de água e gelo, a partir de uma relação obtida no Estado de Rondônia (Brasil. Com estes perfis calculou-se a taxa de aquecimento diabático devido a liberação de calor

  11. Fluxo de calor sensível em cultivo de feijão-caupi Sensible heat flux in cowpea

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    José R. de S Lima

    2011-10-01

    Full Text Available O presente trabalho objetivou comparar o fluxo de calor sensível obtido pelo método do balanço de energia-razão de Bowen (H_B e pelo método aerodinâmico (H_A, em uma área de 4 ha cultivada com feijão-caupi em Areia-PB (6º 58' 12" S e 35º 42' 15" O, 620 m. Foram coletados dados de saldo de radiação, fluxo de calor no solo, temperatura e umidade do solo, temperatura e umidade relativa do ar, velocidade do vento e precipitação pluvial, os quais eram lidos a cada minuto, e armazenados, em uma central de aquisição de dados, como médias a cada 30 min, com exceção da pluviometria, cujo valor foi totalizado no período. Obteve-se excelente concordância entre H_A e H_B, com um índice "d " de 0,980, um erro padrão (EP de 14,88 W m-2, e sem diferença significativa entre H_A e H_B, pelo teste t-Student. Deste modo, o método aerodinâmico pode ser usado em conjunto com medidas de saldo de radiação e de fluxo de calor no solo, para se estimar o fluxo de calor latente e, consequentemente, a evapotranspiração da cultura do feijão-caupi, para as condições edafoclimáticas do Brejo Paraibano.A study was performed to compare the bulk aerodynamic (H_A and Bowen ratio energy balance (H_B methods in the estimation of the sensible heat flux in a cowpea crop. Data of net radiation, soil heat flux, soil water content, soil temperature, air temperature, relative humidity, wind speed and rainfall were collected on 30-min time intervals in an area of 4 ha belonging to the municipality of Areia, PB (6º 58' 12" S e 35º 42' 15" W, 620 m. Results showed that there was a good agreement between H_A and H_B with an index "d" of 0.98 and standard error of estimate (SEE of 14.88 W m-2, no significant difference between H_A H_B, by the t-Student test. Thus, the bulk aerodynamic method can be used in conjunction with measurements of net radiation and soil heat flux to estimate the evapotranspiration of the cowpea under soil and climatic condition of

  12. Artigos esterilizados em calor úmido: validação do sistema de guarda

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    Zilah Cândida Pereira das Neves

    2004-04-01

    Full Text Available Objetivamos identificar o tempo de validade da esterilização dos artigos processados pelo calor úmido, considerando as condições de esterilização e guarda. A validação deu-se através de testes microbiológicos realizados com instrumentais processados numa mesma carga e avaliados em tempos 0, 7, 10, 15 e 25 dias. Foram analisados 30% do instrumental de cada pacote que foi colocado em caldo Mueller Hinton e incubado a 37ºC por 72 horas. A leitura deu-se pela turvação do caldo. Das amostras avaliadas de nove cargas, em nenhuma houve crescimento microbiológico. Concluiu-se que apesar das condições de esterilização e guarda do material não se adequarem totalmente dentro dos parâmetros recomendados pela literatura, a esterilização ocorreu e manteve-se por um período de 25 dias.

  13. Estudo da transferência de calor durante o congelamento de cortes de aves em caixas de papelão ondulado

    OpenAIRE

    Santos, Clarice de Ávila

    2005-01-01

    Dissertação (Mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-graduação em Engenharia de Alimentos O congelamento de produtos alimentícios é um processo complexo que envolve transferência de calor com mudança de fase e ocorre em uma faixa de temperaturas. É realizado, predominantemente, em túneis com convecção forçada de ar, onde o escoamento de ar ocorre em regime turbulento e a transferência de calor do produto para o ar em regime transiente. Quando...

  14. Fluxos de calor no dossel vegetativo e infiltração de água no solo, em floresta tropical Heat fluxes in the vegetative canopy and water infiltration in tropical forest

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    Vanessa de A. Dantas

    2011-12-01

    Full Text Available Este estudo analisou as variações sazonais e anuais dos fluxos de calor sensível e latente, armazenados pelo dossel vegetativo de floresta tropical úmida, bem como a taxa de infiltração de água no solo em duas parcelas experimentais, uma com exclusáo de chuva e outra submetida às condições reais de precipitação pluvial. Os dados aqui usados foram obtidos do projeto ''Estudo da Seca da Floresta (ESECAFLOR, subprojeto do Experimento de Grande Escala da Biosfera-Atmosfera na Amazônia (LBA, conduzido na reserva florestal de terra firme em Caxiuaná, PA. Os dados de temperatura e umidade relativa do ar foram coletados no perfil da floresta amazônica, em intervalos de 8 m, deSd e a superfície até 32 m, durante o ano de 2008, em intervalos horários, para se determinar os fluxos de calor sensível e latente armazenados nos período chuvoso (fevereiro, março e abril e menos chuvoso (setembro, outubro e novembro. Os resultados indicaram que o fluxo de calor sensível armazenado no dossel da floresta no ano de 2008, foi 167,93 W m-2 e o fluxo de calor latente armazenado foi de 5184,38 W m-2. A taxa de infiltração de água do solo na floresta foi reduzida drasticamente nos primeiros minutos do início do experimento, independentemente das condições de umidade do solo e, em seguida, ela apresentou comportamento quase constante ao longo do tempo.This study assessed the seasonal and annual variations in both sensible and latent heat storage fluxes in the canopy air-space of tropical rainforest, as well as the infiltration rate in soil in two experimental plots one with exclusion of rainfall and other under actual rainfall. The data used in this study were obtained during the ''Long-term drought impact on water and carbon dioxide fluxes in Amazonian Tropical Rainforest Experiment'' (ESECAFLOR which is subproject of Large Scale Biosphere Atmosphere Experiment in Amazon forest (LBA, carried out in Caxiuaná National Forest, Pará, Brazil

  15. Global Convergence of the EM Algorithm for Unconstrained Latent Variable Models with Categorical Indicators

    Science.gov (United States)

    Weissman, Alexander

    2013-01-01

    Convergence of the expectation-maximization (EM) algorithm to a global optimum of the marginal log likelihood function for unconstrained latent variable models with categorical indicators is presented. The sufficient conditions under which global convergence of the EM algorithm is attainable are provided in an information-theoretic context by…

  16. Influência do calor armazenado no sistema solo-planta no balanço de energia em pomar de mangueiras Influence of the heat stored in the soil-plant system in the energy balance over a mango orchard

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    Cícera J. R. Borges

    2008-08-01

    Full Text Available Neste estudo se objetivou a avaliação da contribuição do calor armazenado acima das placas de fluxo de calor no solo e no dossel vegetativo sobre os componentes do balanço de energia, no pomar de mangueiras. Os componentes do balanço de energia foram obtidos pelo método do balanço de energia com base na razão de Bowen. O teste t-Student foi usado para avaliar a existência de diferença significativa entre as médias dos componentes do balanço de energia, obtidas mediante as seguintes condições: (i considerando-se o calor armazenado acima dos fluxímetros e (ii desconsiderando-se o calor armazenado acima dos fluxímetros, cujos resultados indicaram que: 1 o efeito do calor armazenado no dossel vegetativo é irrelevante quando comparado com os outros componentes do balanço de energia em pomar de mangueiras; 2 o calor armazenado acima das placas de calor no solo não interfere significativamente no cálculo dos fluxos de calor sensível e latente nem na evapotranspiração da mangueira irrigada; 3 o fluxo de calor no solo, corrigido com o calor armazenado acima dos fluxímetros, difere estatisticamente a nível de 5% de probabilidade, daquele obtido sem a correção do fluxo.The objective of this study was to investigate the contribution of the heat storage above the soil heat flux plates and within the canopy upon the components of the energy balance in the mango orchard. The Bowen energy-ratio balance method was used for obtaining the energy balance components and evapotranspiration of the mango orchard. The t-Student test was applied to evaluate statistical significance of the difference between energy balance component averages under the following conditions: (i considering and (ii not considering the heat storage above the fluximeters. The results suggested that: 1 the canopy heat storage is irrelevant compared to the other energy balance components; 2 the above soil heat plates heat storage does not influence the sensible and

  17. Modelo descritivo do fluxo de calor em soldagem a arco visando o conceito de calor imposto efetivo Descriptive model of the heat flow in arc welding targeting the concept of effective heat input

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    Américo Scotti

    2012-06-01

    Full Text Available O objetivo do presente trabalho é propor um modelo global para descrever o fluxo de calor em soldagem a arco, visando o entendimento dos fenômenos relacionados com o fluxo de calor. A tentativa é suprir uma lacuna do conhecimento gerado entre a aplicação de modelos analíticos simplificados (não totalmente realistas e de modelos numéricos (que mascaram a visão física dos fenômenos. Inicia-se propondo uma descrição mais física para a razão da queda de tensão num arco, baseada na geração e perda de calor para se manter o equilíbrio da desionização e reionização, em contraste com a abordagem em que o arco é comparável a um resistor elétrico. Em seguida, se propõe um modelo descritivo da subsistência térmica de um arco, para qualificar as formas de transferência de calor do arco para a chapa. Um segundo modelo descritivo é então proposto para explicar como o calor entra, difunde e sai da chapa durante a soldagem. Finalmente, é discutido como a aplicação destes dois modelos de forma global permite entender que nem todo o fluxo de calor do arco para a chapa vai afetar a velocidade de resfriamento nas regiões do material aquecidas. Culmina-se com a proposta do emprego do termo Calor Imposto Efetivo como meio de evidenciar o parâmetro de calor de importância a ser determinado em soldagem.The objective of the present paper is to propose a global model for describing heat flow in arc welding, aiming the understanding of the phenomena involved. The attempt is to fill out a gap of knowledge which has been generated between the application of simplified analytical models (not totally realistic and numerical models (that disguises the physics of the phenomena. Initially, a physic-oriented description of the reasons for welding arc voltage drop is presented. This description is based on the heat generation and its losses to maintain the balance between deionization and reionization, in contrast to the approach that the arc

  18. O estudo da prova calórica em pacientes idoso The study of caloric testing in senior patients

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    Débora Cristina de Oliveira Bezerra

    2008-01-01

    Full Text Available OBJETIVO: realizar o estudo da prova calórica em pacientes idosos com queixa de tontura, acompanhada ou não de zumbido com finalidade de traçar um perfil dos idosos quanto os sintomas vestibulares. MÉTODOS: fizeram parte da amostra 143 pacientes, com faixa etária variando de 60 a 90 anos de idade; todos realizaram o exame otoneurológico. Foram excluídos pacientes idosos com queixa de desequilíbrio e aqueles que apresentaram a queixa de zumbido desacompanhado da tontura. RESULTADOS: o estudo demonstrou que a normorreflexia, em valores absolutos, encontra-se entre 82,3% a 91,2% e os valores relativos são de 93%. Referente aos dados colhidos na anamnese, o que chamou a atenção, foi que do total de pacientes analisados, encontrou-se a tontura acompanhada de zumbido em 69% dos casos e o elevado uso de medicação em pacientes nesta faixa etária. CONCLUSÃO: na população estudada houve um predomínio da tontura acompanhada de zumbido. Em relação à prova calórica, o trabalho demonstrou a alta prevalência de pacientes com valores absolutos e relativos normais.PURPOSE: to accomplish the study of caloric testing in senior patients with dizziness, accompanied or not of with buzzing. METHODS: 143 patients were analyzed with age varying from 60 to 90 years; all of them did an otoneurologic evaluation. Senior patients with unbalance complaints and with buzzing unaccompanied with dizziness were excluded from this study. RESULTS: 82.3% to 91.2% of the patients obtained normoreflexia in absolute values and over 93% obtained normal results in relative values. Referring to the data obtained in the anamnesis, what got attention was 69% of dizziness accompanied with buzzing. And the high medication of the patients in this age group. CONCLUSION: there was a prevalence of dizziness accompanied with buzzing in the studied population. Concerning the caloric testing, the study demonstrated the high prevalence of patients with normal absolute and

  19. Estimulação calórica a ar em mastoidectomias abertas unilaterais Air caloric test in canal wall down mastoidectomy

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    Lucia Kazuko Nishino

    2012-06-01

    Full Text Available Poucos trabalhos desde a década de 70 foram realizados a fim de elucidar a prova calórica em alterações da orelha média, apesar de inúmeras controvérsias que este exame pode trazer em estruturas anatômicas tão distintas. Na mastoidectomia radical, estes estudos são mais escassos. OBJETIVO: Este estudo teve como objetivo analisar os achados da estimulação calórica a ar em indivíduos com mastoidectomia radical unilateral sem queixas de tontura. MATERIAL E MÉTODO: Estudo prospectivo, realização da estimulação calórica a ar em 36 indivíduos sem queixas vestibulares, sendo 21 com cirurgia de mastoidectomia aberta unilateral e 15 sem nenhuma alteração na orelha média ou externa. RESULTADOS: 80,95% dos indivíduos apresentaram respostas assimétricas na prova calórica frias, sendo as respostas maiores do lado da mastoidectomia aberta. Em 72,73%, o mesmo efeito ocorreu com a prova calórica quente. Na análise das quatro estimulações, encontrou-se assimetria das provas quente e frias em 81,82% dos casos. Em 47,61%, foi encontrada estimulação paradoxal da prova calórica quente. CONCLUSÃO:As respostas nistágmicas do lado da mastoidectomia aberta foram maiores se comparadas com o lado saudável. A estimulação paradoxal da prova calórica quente foi um achado frequente. Não foram encontradas respostas hipofuncionantes.Since the 1970s, few studies have been conducted to elucidate the use of caloric tests on middle ear disorders, despite the many controversies that this test may produce in anatomical structures that are so distinct. In cases of mastoidectomy, such studies are even rarer. OBJECTIVE: This study aims to analyze the findings from air caloric stimulation done in individuals submitted to unilateral radical mastoidectomy without complaints of dizziness. MATERIALS AND METHOD: Thirty-six individuals without vestibular complaints were enrolled in this prospective study. Air caloric stimulation was offered to all

  20. TRANSPIRAÇÃO EM COFFEA CANEPHORA L. VIA BALANÇO DE CALOR NO CAULE E LISÍMETRO DE PESAGEM ELETRÔNICA

    OpenAIRE

    2016-01-01

    O consumo de água em uma planta de café conilon cultivado em lisímetro foi avaliado. O experimento objetivou estudar a transpiração diária do café e foi realizado no Departamento de Energia Nuclear da UFPE, em Recife – PE, em 2011, por meio de dois métodos: a) lisimetria, por análise de variação de massa; b) fluxo de seiva via método térmico do balanço de calor no caule. A área foliar variou de 1,39 a 1,87 m2 durante o experimento. O consumo de água medido através do lisímetro variou entre 2,...

  1. Latent manganese deficiency increases transpiration in barley (<em>Hordeum vulgareem>)

    DEFF Research Database (Denmark)

    Hebbern, Christopher Alan; Laursen, Kristian Holst; Ladegaard, Anne Hald;

    2009-01-01

    To investigate if latent manganese (Mn) deficiency leads to increased transpiration, barley plants were grown for 10 weeks in hydroponics with daily additions of Mn in the low nM range. The Mn-starved plants did not exhibit visual leaf symptoms of Mn deficiency, but Chl a fluorescence measurements...

  2. Ações fisiológicas do calor e do ácido sulfúrico em sementes de Brachiaria brizantha cultivar marandu Physiological actions of heat and sulphuric acid on Brachiaria brizantha 'marandu' seeds

    Directory of Open Access Journals (Sweden)

    Leila Martins

    2006-01-01

    Full Text Available Objetivando aprimorar o método de aplicação de calor para a superação da dormência de sementes de Brachiaria brizantha cultivar Marandu, foi estudado o comportamento fisiológico de amostras de dez lotes de sementes dessa forrageira, com taxas de dormência superiores a 25%, quando expostas à temperatura de 70 ºC por 5, 10, 15, 20, 25 e 30 horas e à imersão em ácido sulfúrico concentrado por 15 minutos. No início (efeito imediato e após seis meses (efeito latente de armazenamento em condições ambientes não controladas, foram feitas as seguintes avaliações: teor de água, germinação, viabilidade pelo tetrazólio, emergência em areia, índice de velocidade de emergência e comprimento da parte aérea das plântulas. Pelos resultados verificou-se que as exposições das sementes a 70 ºC ou a ácido sulfúrico concentrado reduzem a taxa de dormência e favorecem o desempenho fisiológico. Após seis meses de armazenamento, as sementes submetidas a 70 ºC por 5 horas mostram desempenho superior às dos demais tratamentos.Aiming at to improve the methodology for application of heat to break dormancy seeds of Brachiaria brizantha `Marandu', the physiological performance of samples of ten seed lots of this forage, with dormancy indices superior to 25%, was studied after exposure to 70 ºC for 5, 10, 15, 20, 25 and 30 hours and immersion in concentrated sulphuric acid for 15 minutes. At the beginning (immediate effect and after six months (latent effect storage under ambient uncontrolled conditions, the following evaluations were made: water content, germination, tetrazolium viability, sand emergence, speed of emergence index and shoot length. Results indicated that exposure of seeds to 70 ºC or to concentrated sulphuric acid reduce the dormancy rate and favor the physiological performance; after six months, the seeds submitted to 70 ºC for 5 hours show performance superior to those of the other treatments.

  3. Sinterização de filmes finos de LiNbO3 em forno microondas: estudo da influência da direção do fluxo de calor

    OpenAIRE

    N. S. L. S. Vasconcelos; J. S. Vasconcelos; V. Bouquet; S. M. Zanetti; E. R. Leite; Longo, E.; Bernardi,M. I.; Perrin, A.; Guilloux-Viry, M.; J. A. Varela

    2004-01-01

    Filmes finos de LiNbO3 foram preparados pelo método dos precursores poliméricos e depositados por "spin coating" sobre substratos de safira (0001). Os filmes foram tratados em forno microondas doméstico a 400 ºC por 15 e 20 min. Um material com alta perda dielétrica (susceptor de SiC) foi usado para absorver energia das microondas e transformá-la em calor. Este calor foi transferido para o filme a fim de promover a sua cristalização. O susceptor foi posicionado acima do filme ou embaixo do su...

  4. BALANÇO DE ENERGIA EM UMA CULTURA DE MILHETO

    Directory of Open Access Journals (Sweden)

    Sandro Luis Petter Medeiros

    1993-04-01

    Full Text Available Em uma cultua de milheto forrageiro (Pennisetum americanum, Leek cv. pérola, em Eldorado do Sul, com coordenadas de 30°05'22"S e 51°40'18"W e 40m de altitude, foram determinados os componentes do balanço de energia na ano agrícola de 1988/89. O fluxo de calor latente de evaporação utilizou a maior porção da energia disponível no sistema, sendo uma função direta da disponibilidade hídrica no solo. O fluxo de calor sensível foi o segundo termo no consumo de energia disponível, variando segundo uma função inversa da disponibilidade hídrica. O fluxo de calor no solo variou inversamente ao índice de área foliar, utilizando a menor fração do saldo de radiação. Em geral, os fluxos de calor sensível no ar e no solo foram positivos somente nas primeiras horas da manhã e ao final da tarde. Em alguns horários houve aporte de energia por advecção, invertendo o gradiente térmico vertical do ar e incrementando o fluxo de calor latente de evaporação.

  5. Alterações fenotípicas em cultivares de alface selecionadas para calor Phenotypical alterations in lettuce genotypes selected for heat tolerance

    Directory of Open Access Journals (Sweden)

    José Henrique Conti

    2000-11-01

    Full Text Available Cultivares de alface selecionadas para o pendoamento lento e as mesmas que lhes deram origem foram analisadas quanto a variações morfológicas, com o objetivo de quantificar possíveis modificações adaptativas para as condições de cultivo em épocas de calor. Cultivares dos grupos "manteiga" (Regina, Glória, IAC 303, IAC 202, Sem Rival e Luciana "folha crespa" (Grand Rapids e Brisa e "americana" (Great Lakes e Mesa 659, foram avaliadas em dois plantios de verão, em Piracicaba, em delineamento de blocos casualizados. No primeiro experimento, (novembro/90, foram avaliadas as características de número de estômatos, espessura de folha e quantidade de clorofila total. No segundo, (setembro/91, foram avaliados o peso seco, peso fresco, porcentagem de matéria seca, tempo para pendoamento e número de folhas. As cultivares selecionadas para calor no grupo "manteiga" (Glória e Regina, apresentaram maior número de estômatos (respectivamente 9487/cm² e 7973/cm² e folhas mais grossas (respectivamente 556 mm e 439 mm e também, acumularam maior quantidade de matéria seca (respectivamente 24,55 g e 25,50 g. A cultivar selecionada para calor do grupo "folha crespa" (Brisa acumulou maior quantidade de matéria verde (446,77g e seca (22,40 g, da mesma forma que apresentou maior quantidade de estômatos (7.279/cm². Para as cultivares do grupo "americana", observou-se diferença significativa apenas para espessura de folha, sendo que a cultivar Mesa 659 apresentou folhas mais grossas (589 mm. Constataram-se aumentos significativos da biomassa vegetal nas cultivares selecionadas para calor em relação àquelas não selecionadas. As cultivares que atingiram maior produtividade de matéria seca por planta foram Mesa 659 (28,74 g, Great Lakes (27,17 g e Regina. Os resultados comprovaram que a seleção para o pendoamento lento indiretamente produziu variações adaptativas nas plantas de alface.Lettuce cultivars selected for slow bolting and

  6. Isla de calor y ocupación espacial urbana en San Juan, Argentina: análisis evolutivo. Island heat effect and spatial urban occupancy in San Juan, Argentina: evolution analysis Ilha de calor e ocupação do espaço urbano em San Juán, Argentina: análise evolutiva

    Directory of Open Access Journals (Sweden)

    Mario Cúnsulo

    2011-06-01

    Full Text Available Resumen:En este artículo se presentan resultados finales de un proyecto de investigación bianual (2009-2010, denominado Variación histórica y espacial de la isla de calor urbana en zona árida, financiado por la Universidad Nacional de San Juan, Argentina. Su objetivo principal es determinar la progresiva modificación de la isla de calor urbana en un periodo de quince años (1995-2010 y la correlación de esta con la ocupación del área urbana del Gran San Juan (GSJ, localizada en la diagonal árida de Sudamérica. Los resultados obtenidos demuestran la interrelación entre la ocupación urbana y la espacialización de la isla de calor en la ciudad.Abstract:In this paper, final result of a bi-annual project (2009-2010 called Historic and spatial variation of the urban island heat effect in an arid zone –financed by Universidad Nacional de San Juan, Argentina –are presented. Its main aim is determining the progressive changing of urban island heat effect during a fifteen year period (1995-2010 and its correlationwith the occupancy of Great San Juan (GSJ urban area, located in South America’s arid diagonal. Results show the interrelationship between urban occupancy and the spread of island heat effect in the city.Resumo:Este artigo apresenta resultados finais do projeto de pesquisa de dois anos (2009-2010, chamado A variação histórica e espacial da ilha de calor urbana em uma zona árida, financiado pela Universidad Nacional de San Juán, Argentina. Seu principal objetivo é determinar a modificação progressiva da ilha de calor urbana por um período de 15 anos (1995-2010 e a correlação desta com a ocupação da área urbana da Gran San Juan (GSJ, localizada na diagonal árida de América do Sul. Os resultados obtidos demonstram a relação entre ocupação urbana e espacialização da ilha de calor na cidade.

  7. Início da tuberização, duração do ciclo vegetativo e tolerância ao calor em genótipos de batata

    Directory of Open Access Journals (Sweden)

    Danilo Hottis Lyra

    2015-07-01

    Full Text Available Resumo: O objetivo deste trabalho foi avaliar a relação do tempo para o início da tuberização e da duração do ciclo vegetativo com a tolerância ao calor em batata. Grupos de clones com diferentes tempos para o início de tuberização e durações do ciclo vegetativo foram definidos e avaliados em dois ambientes, e seus índices morfofisiológicos foram estimados em condições de estresse de calor. A amplitude para o início da tuberização foi de 31,8 dias e para a duração do ciclo vegetativo de 30,3 dias. Os grupos de clones formados apresentaram os seguintes parâmetros: tuberização precoce e ciclo vegetativo curto, tuberização precoce e ciclo longo (PL, tuberização tardia e ciclo curto e tuberização tardia e ciclo longo. Em condições de estresse de calor, a produção de tubérculos graúdos do grupo PL apresentou média superior à dos demais grupos. Seis clones (IRF 10-24, IRF 7-61, IRF 2-71, IRF 2-14, IRF 6-104 e IRF 10-44 e três testemunhas ('Markies', CBM 16-16 e CBM 9-10 foram considerados tolerantes ao estresse de calor (média diária de 21,2ºC e responderam favoravelmente ao ambiente com temperaturas amenas (média diária de 19,0ºC. A partição de matéria seca para os tubérculos foi mais rápida nos clones do grupo PL. Os clones de tuberização precoce e ciclo vegetativo longo apresentaram maior tolerância ao calor, com maior produção de tubérculos do que os demais grupos.

  8. Cluster headache attacks in a woman previously struck by lightning: pathophysiology of the latent period Cefaléia em salvas em uma mulher que foi previamente atingida por raio: fisiopatologia do período latente

    Directory of Open Access Journals (Sweden)

    Marcelo Moraes Valença

    2007-06-01

    Full Text Available BACKGROUND: Cases of patients who developed cluster headache-like symptoms after different putative causes have been reported, indicating a direct relationship between brain lesion and this particular type of headache. Long term, delayed, neurological sequelae after lightning have also been described. CASE REPORT: We describe the case of a woman who, at the age of 10, was struck by lightning. Six years later she developed cluster headache-like attacks. CONCLUSION: We hypothesize that a relationship between the lightning and the cluster headache-like episodes observed in our patient. This case study may have helped throw some light into the still unknown pathophysiology of this particular type of primary headache.INTRODUÇÃO: Foram descritos casos de pacientes que desenvolveram cefaléia em salvas como manifestação secundária à diferentes causas, indicando uma relação direta entre uma lesão cerebral e este tipo particular de cefaléia. Seqüelas neurológicas tardias após injúria elétrica por raio também têm sido descritas. RELATO DO CASO: Nós descrevemos o caso de uma mulher que aos 10 anos de idade foi atingida por um raio. Seis anos mais tarde desenvolveu sintomatologia de cefaléia em salvas. CONCLUSÃO: Acreditamos que pode haver relação entre a injúria elétrica causada pelo raio e o aparecimento dos episódios semelhantes à cefaléia em salvas observados na nossa paciente. A provável fisiopatologia envolvida na gênese da cefaléia em salvas de origem secundária é discutida, particularmente em relação ao intervalo latente entre a injúria precipitante inicial e a fase álgica da cefaléia.

  9. Tuberculose em pacientes com artrite reumatoide: a dificuldade no diagnóstico da forma latente Tuberculosis in rheumatoid arthritis patients: the difficulty in making the diagnosis of latent infection

    Directory of Open Access Journals (Sweden)

    Daniela Graner Schuwartz Tannus Silva

    2010-04-01

    Full Text Available Desde o início do uso de drogas anti-TNF para o tratamento da artrite reumatoide e outras doenças inflamatórias, casos de tuberculose pulmonar e extrapulmonar vêm sendo notificados em pacientes submetidos a tal tratamento. Na maioria das vezes, a doença se desenvolve durante as seis primeiras infusões. Todo paciente deve ser avaliado para tuberculose latente antes do início do uso de um bloqueador de TNF; no entanto, o diagnóstico de tuberculose latente é um desafio. A prova tuberculínica, o único teste disponível para a detecção de tuberculose latente por quase um século, apresenta uma série de limitações. Testes baseados na detecção da produção de IFN-γ in vitro por células mononucleares ativadas por antígenos específicos parecem ser mais acurados e vêm sendo pesquisados em pacientes com artrite reumatoide.Since the beginning of the use of anti-TNF in the treatment of rheumatoid arthritis and other inflammatory diseases, cases of pulmonary tuberculosis and extrapulmonary tuberculosis have been reported in patients receiving such treatment. In most cases, the disease develops by the time the patient has received the sixth infusion. Every patient should be evaluated for latent tuberculosis infection prior to the use of a TNF inhibitor. However, the diagnosis of latent tuberculosis infection is a challenge. The tuberculin test, which was the only test available to detect latent tuberculosis infection for nearly a century, presents a number of limitations. Tests based on the detection of the in-vitro production of IFN-γ by mononuclear cells activated by specific antigens appear to be more accurate and have been studied in patients with rheumatoid arthritis.

  10. Uso de rações modificadas para suínos em terminação mantidos em ambiente de conforto ou de calor

    OpenAIRE

    2014-01-01

    Objetivou-se avaliar o efeito de dietas formuladas com redução do teor de proteína bruta (PB), suplementadas com aminoácidos sintéticos, e inclusão de óleo de soja (OS) em dietas isocalóricas, no ambiente de estresse calórico (31ºC) e conforto térmico (19ºC), sobre o desempenho, características de carcaça, parâmetros fisiológicos de suínos em terminação. Foram utilizados 120 suínos machos castrados de linhagem comercial, com peso inicial médio de 68,0± 1,9 kg, em um período experimental de 30...

  11. EM study of latent track morphology in TiO2 single crystals

    Science.gov (United States)

    O'Connell, J. H.; Skuratov, V. A.; Akilbekov, A.; Zhumazhanova, A.; Janse van Vuuren, A.

    2016-07-01

    A TEM investigation was conducted into the morphology of 167 MeV Xe (2 × 1010 cm-2 to 1014 cm-2) and 1 GeV Bi ion (2 × 1010 cm-2) induced latent tracks in single crystal TiO2 (rutile). At fluences up to 1011 cm-2 latent tracks are visible as discontinuous lines of strained crystal along the ion trajectory. From the implanted surface down to about 60-70 nm below the surface the tracks appear as continuous conical structures with a base of diameter 5-6 nm (Xe) and 8-9 nm (Bi) in contact with the surface with a mushroom shaped hillock extending outward from the surface. At fluences between 6 × 1012 cm-2 and 1013 cm-2 the crystal is amorphized but rod-like crystalline regions remain which are oriented along the ion trajectories. Amorphization extends from the surface down to 8.3 μm below suggesting an upper limit for the threshold electronic stopping power for amorphization of 7.3 keV nm-1. At 1014 cm-2 Xe the entire 8.3 μm subsurface region is rendered amorphous although some evidence of short range ordering remains.

  12. EM study of latent track morphology in TiO{sub 2} single crystals

    Energy Technology Data Exchange (ETDEWEB)

    O’Connell, J.H., E-mail: joconnell@nmmu.ac.za [CHRTEM, NMMU, University Way, Summerstrand, Port Elizabeth (South Africa); Skuratov, V.A. [FLNR, JINR, Joliot-Curie 6, 141980 Dubna (Russian Federation); Akilbekov, A.; Zhumazhanova, A. [L.N. Gumilyov Eurasian National University, Astana (Kazakhstan); Janse van Vuuren, A. [CHRTEM, NMMU, University Way, Summerstrand, Port Elizabeth (South Africa)

    2016-07-15

    A TEM investigation was conducted into the morphology of 167 MeV Xe (2 × 10{sup 10} cm{sup −2} to 10{sup 14} cm{sup −2}) and 1 GeV Bi ion (2 × 10{sup 10} cm{sup −2}) induced latent tracks in single crystal TiO{sub 2} (rutile). At fluences up to 10{sup 11} cm{sup −2} latent tracks are visible as discontinuous lines of strained crystal along the ion trajectory. From the implanted surface down to about 60–70 nm below the surface the tracks appear as continuous conical structures with a base of diameter 5–6 nm (Xe) and 8–9 nm (Bi) in contact with the surface with a mushroom shaped hillock extending outward from the surface. At fluences between 6 × 10{sup 12} cm{sup −2} and 10{sup 13} cm{sup −2} the crystal is amorphized but rod-like crystalline regions remain which are oriented along the ion trajectories. Amorphization extends from the surface down to 8.3 μm below suggesting an upper limit for the threshold electronic stopping power for amorphization of 7.3 keV nm{sup −1}. At 10{sup 14} cm{sup −2} Xe the entire 8.3 μm subsurface region is rendered amorphous although some evidence of short range ordering remains.

  13. Gasto energético e consumo calórico em adolescentes do sexo masculino com diferentes níveis de adiposidade corporal Energy expenditure and caloric intake among male adolescents with different levels of body adiposy

    Directory of Open Access Journals (Sweden)

    Diego Augusto Santos Silva

    2013-03-01

    Full Text Available Foram comparados o gasto energético e consumo calórico de adolescentes com diferentes níveis de gordura corporal. Estudo transversal com 40 adolescentes de 14 a 16 anos do sexo masculino. Os adolescentes foram divididos em dois grupos, cada um com 20 sujeitos, de acordo com o %G: baixo (%G 20%. O gasto energético foi mensurado por acelerômetros triaxiais e recordatório de atividades diárias. O consumo calórico foi avaliado pelo registro de 24 horas. Os jovens com baixo %G tiveram menor consumo calórico ( = 2408,1 ± 557,9 kcal.dia-1 em comparação aos jovens com alto %G ( = 2931,7 ± 679,2 kcal.dia-1, pEnergy expenditure and caloric intake were compared among adolescents with different levels of adiposity. A cross-sectional study was carried with 40 adolescent boys aged 14 to 16 years. The adolescents were divided into two groups of 20 subjects each, according to % body fat (%BF: low ( 20%. Energy expenditure was measured using accelerometer and daily activity diary. The dietary pattern was evaluated based on 24-h recall. Caloric intake was lower in adolescents with low %F ( = 2408.1 ± 557.9 kcal.day-1 compared to those with high %F ( = 2931.7 ± 679.2 kcal.day-1, p<0.05. In addition, they presented greater relative energy expenditure than adolescents with high %F (p<0.05. High %F adolescents showed larger caloric intake than expenditure, while the opposite was observed among low %F males.

  14. Sinterização de filmes finos de LiNbO3 em forno microondas: estudo da influência da direção do fluxo de calor Sintering of LiNbO3 thin films in microwave furnace: study of the influence of the heat flow direction

    OpenAIRE

    N. S. L. S. Vasconcelos; J. S. Vasconcelos; V. Bouquet; S. M. Zanetti; E. R. Leite; Longo, E.; Bernardi,M. I.; Perrin, A.; Guilloux-Viry, M.; J. A. Varela

    2004-01-01

    Filmes finos de LiNbO3 foram preparados pelo método dos precursores poliméricos e depositados por "spin coating" sobre substratos de safira (0001). Os filmes foram tratados em forno microondas doméstico a 400 ºC por 15 e 20 min. Um material com alta perda dielétrica (susceptor de SiC) foi usado para absorver energia das microondas e transformá-la em calor. Este calor foi transferido para o filme a fim de promover a sua cristalização. O susceptor foi posicionado acima do filme ou embaixo do su...

  15. Ativação da proteína TGFbetaI latente em pulmão irradiado in vivo Latent TGFbeta1 activation in the lung irradiated in vivo

    Directory of Open Access Journals (Sweden)

    MARCOS DUARTE MATTOS

    2002-12-01

    Full Text Available OBJETIVO: Investigar no pulmão, por imunohistoquímica, a localização das proteínas TGFbeta1 latente e TGFbeta1 ativa, se ocorre ativação radioinduzida da proteína TGFbeta1 latente e a distribuição das fibras colágenas em diversos períodos de tempo após irradiação. MÉTODOS: 32 camundongos isogênicos (C57BL foram divididos em dois grupos: GI (não irradiado com 12 animais e GII (irradiado com 20 animais. Os animais do GII receberam radiação gama (telecobaltoterapia, 60Co, com rendimento de 0,97Gy/min, dose única de 7Gy em corpo inteiro. Os camundongos dos grupos I e II foram sacrificados por estiramento cervical nos períodos de 1, 14, 30 e 90 dias após irradiação. RESULTADOS: Os pulmões irradiados apresentaram: 1 congestão vascular e espessamento dos septos alveolares aos 30 dias e mais intensamente aos 90 dias depois da irradiação; 2 aumento significante da deposição de colágeno em todos os períodos de tempo após irradiação; 3 fraca ativação da proteína TGFbeta1 latente em um dia e intensa aos 14 dias depois da irradiação em brônquios e alvéolos. Nossos resultados sugerem que células dos brônquios e alvéolos podem participar do complexo mecanismo de fibrose pulmonar radioinduzida atuando como fontes da proteína TGFbeta1 ativa.PURPOSE: assess the latent and active TGFb1 localization in the lung, whether or not radiation induces latent TGFbeta1 activation, and the distribution of collagen fibers in the irradiated lung. METHODS: Thirty two C57BL mice were randomly assigned in two groups: GI (non irradiated animals and GII (irradiated animals. The mice from GII received a single whole ¾ body radiation dose of 7Gy, using a 60Co source at a dose rate of 0.97 Gy/min. They were sacrificed by cervical dislocation at 1, 14, 30 and 90 days after radiation. RESULTS: The irradiated lungs showed: 1 vascular congestion and thickness of the alveolar septa 30 days and more intense 90 days after irradiation; 2

  16. Perda de calor determinada pela exposição das alças intestinais em ratos Heat loss caused by bowel exposition to room temperature in rats

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Von Bahten

    2006-10-01

    Full Text Available OBJETIVO: Esta pesquisa tem por objetivo quantificar a perda de energia calórica que ocorre ao realizarmos uma laparotomia com exposição de alças intestinais à atmosfera em ratos; determinar a perda termodinâmica representada por watts/m² em função da superfície peritoneal exposta do animal e discutir meios de tratamento para a perda de calor. MÉTODO: Foram utilizados 30 ratos machos, Wistar, distribuídos em cinco grupos de seis animais cada, com idade de 8 a 9 semanas, com o peso entre 200 e 220g. No grupo A ou grupo controle, os animais foram submetidos a anestesia inalatória. No grupo B, os ratos foram submetidos a uma laparotomia mediana com exposição das alças intestinais. Nos grupos C, D e E, os ratos foram submetidos a uma laparotomia mediana com exposição das alças intestinais e tratados respectivamente, por gaze úmida, gaze seca e empacotamento com filme de poliéster. RESULTADOS: Observou-se uma significativa perda de energia calórica quando se realiza uma laparotomia com exposição das alças intestinais em ambiente não controlado, da ordem de 620,72 kJ/m² A análise da perda termodinâmica, em função da superfície corpórea exposta do rato, apresentou um valor de 382,97 W/m². CONCLUSÕES: Na avaliação dos diferentes tipos de tratamento utilizados para prevenir a perda de calor corpóreo, ficou evidente que a utilização do filme de poliéster (PVC foi o método mais efetivo na conservação do calor, em relação à gaze seca e, ou úmida respectivamente.BACKGROUND: This study has the intent to quantify the caloric energy loss that occurs when a laparotomy is done and the bowel is exposed to room temperature in rats; to find the thermodynamic loss measured in watt/m² over the rat peritoneal area exposed and discuss ways to manage that heat loss. METHODS: This research project used 30 male rats, Wistar, separated in 5 groups of 6 animals, from 8 to 9 weeks old and weighting between 200 to 220g. Group A

  17. Efeito dos conservantes sobre a densidade calórica em músculos de Hoplias aff. malabaricus (Bloch, 1794 (Osteichthyes, Erythrinidae Effect of preservatives on caloric density in the muscles of Hoplias aff. malabaricus (Bloch, 1794 (Osteichthyes, Erythrinidae

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    Milena Morimoto

    2002-05-01

    Full Text Available A conservação de amostras para a determinação dos valores calóricos em estudos de bioenergética de peixes tem se apresentado, na literatura, com uma variedade de métodos. Com o intuito de identificar o efeito de conservantes sobre os resultados obtidos com as diferentes técnicas de conservação, foram coletados exemplares adultos de Hoplias aff. malabaricus (Osteichthyes, Erythrinidae na planície de inundação do rio Paraná. De cada exemplar, foram retiradas 5 amostras da musculatura, as quais foram submetidas aos seguintes tratamentos: formol (4%, álcool (70%, congelamento (-10oC, nitrogênio líquido (-180oC e estufa à 60oC (amostra controle. Depois de 30 dias, todas as amostras foram secas em estufa à 60oC e posteriormente procedeu-se à determinação calórica de cada uma das amostras em bomba calorimétrica. Detectaram-se diferenças significativas entre os tratamentos (ANOVA: N=206; F=50,28; pThe preservation of samples for caloric values determination in bioenergetic studies of fish has been presented literature with a variety of methods. To identify the effect of preservatives over the results obtained with different preservation techniques, adult individuals of Hoplias aff. malabaricus (Osteichthyes, Erythrinidae were collected in Paraná river floodplain. From each fish, five samples were extracted from its dorsal muscle and submitted each sample for a different treatment: ice (-10ºC, formaldehyde (4%, alcohol (70%, liquid nitrogen (-180oC and a control sample immediately oven dried (60oC. After 30 days, the treatments were oven dried (60oC and caloric values of each sample were determined in a caloric bomb. Significant differences among the treatments were found (ANOVA: n = 206; F = 50.28; p < 0.001. Some evaluations of the effects of each treatment were presented for further comparisons with the results published in literature.

  18. Respostas termorregulatórias de crianças no exercício em ambiente de calor Respuestas termorreguladoras de niños en el ejercicio en ambiente de calor Thermoregulatory responses of children exercising in a hot environment

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    Luis Henrique L. S. Gomes

    2013-03-01

    Full Text Available OBJETIVO: Revisar as possíveis peculiaridades nos mecanismos biológicos referentes às respostas termorregulatórias e sudorípara específicas no exercício realizado por crianças em ambiente de calor. FONTES DE DADOS: Foi feita uma revisão de 47 artigos publicados entre 1960 e 2011 nas bases de dados eletrônicos MedLine e SciELO Brasil, com a utilização dos seguintes descritores: 'crianças', 'calor', 'sudorese', 'termorregulação', 'glândula sudorípara' e 'exercício', sendo usados isoladamente ou em combinação, além de uma tese de doutorado sobre o assunto. SÍNTESE DOS DADOS: Em pré-púberes, a taxa de sudorese durante o esforço é menor em comparação aos adultos. Crianças possuem características termorregulatórias diferenciadas, apresentando um débito de suor por glândula muito menor. A maior razão entre área de superfície e massa corporal faz com que crianças absorvam mais calor durante o exercício sob estresse térmico, elevando o risco de apresentarem sintomas de hipertermia. O maior fluxo sanguíneo para a pele contribui com um melhor controle da homeostase térmica de crianças. O menor tamanho da glândula, a menor sensibilidade colinérgica, os níveis baixos de catecolaminas circulantes durante o esforço e a falta de hormônio androgênico explicam a ocorrência da baixa eliminação de suor no exercício realizado por crianças. CONCLUSÕES: Crianças exibem glândulas sudoríparas imaturas. Assim, a prática de atividade física combinada a altas temperaturas não é bem tolerada havendo maior vulnerabilidade às lesões térmicas. No calor, deve-se ter um controle rigoroso da ingestão de líquidos e um monitoramento atencioso das condições climáticas para maior segurança na prática de exercícios.OBJETIVO: Revisar las posibles peculiaridades en los mecanismos biológicos referentes a las respuestas termorreguladoras y sudorípara específicas en el ejercicio realizado por niños en ambiente de

  19. Calibrated heat-pulse method for the assessment of maize water uptake Desenvolvimento do método do "pulso de calor" para determinação da absorção hídrica em milho

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    Antonio Odair Santos

    2000-03-01

    Full Text Available Plant water requirements are important aspects of crop production to be determined in the field, in order to judiciously manage crop water usage. Water uptake by field grown maize (Zea mays L., under well-watered conditions was verified with the heat-pulse system. The temperature difference between two radially inserted thermocouples, one 9 mm above and the other 4 mm below a heater piercing the maize stem, was measured every 0.3 seconds following emission of a heat-pulse. Comparisons of the heat-pulse system outputs, lysimetric measurement and transpiration model estimates were monitored on an hourly and daily basis. At normal and low atmospheric demand daily and hourly values of heat-pulse outputs and lysimetric measurement showed good agreement. Hourly agreement of a modified Penman-Monteith energy balance equation estimate and heat-pulse outputs showed accordance between measurement of sap flow and the plant water-loss theory. Study of the relationship between maize canopy water loss rate and heat velocity in the stem showed that these two parameters were proportional and a calibration factor of 1.51 for full soil foliage coverage was verified.A determinação a campo das necessidades hídricas de plantas é um aspecto importante da produção agrícola, para o manejo correto do uso da água pelos cultivos. A absorção de água por uma cultura de milho (Zea mays L., cultivado a campo, em condições de não limitação hídrica, foi verificada através da técnica do pulso de calor. Após a emissão de um pulso, procedeu-se a medições, a cada 0,3 segundos, do diferencial de temperatura entre dois termopares, inseridos radialmente no caule da planta. O primeiro foi colocado 9 mm acima e o segundo 4 mm abaixo de uma fonte de calor ("heater". Foram feitas comparações entre as medições feitas pela técnica do pulso de calor, lisímetro e estimativas da transpiração computadas em modelo, numa base horária e diária. Comparações entre

  20. Níveis de cromo orgânico na dieta de codornas japonesas mantidas em estresse por calor na fase de postura Levels of organic chromium on diet of laying Japanese quails under heat stress

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    Marcelle Santana de Araújo

    2007-06-01

    Full Text Available O experimento foi conduzido com objetivo de avaliar o efeito da adição de cromo orgânico (Cr na alimentação de codornas japonesas na fase inicial de postura mantidas em estresse por calor. Seiscentas codornas com 63 dias de idade e peso inicial de 158,6 g foram mantidas em ambiente de alta temperatura (32ºC e alimentadas com dietas à base de milho e farelo de soja suplementadas com Cr (cromo-metionina em substituição ao inerte (0, 500, 1.000, 1.500 e 2.000 ppb. O delineamento utilizado foi o inteiramente casualizado, com cinco tratamentos, 12 repetições e dez aves por unidade experimental, adotando-se o teste de Willians a 5% de significância (a para análise de cada variável: produção de ovos (taxa de postura/ave/dia; taxa de postura por ave alojada; taxa de postura de ovos comercializáveis; peso de ovo; consumo de ração; conversão alimentar (por kg e por dúzia de ovos; e massa de ovos. O fornecimento de cromo orgânico no nível de 500 ppb promoveu melhora na produção de ovos comercializáveis e, no nível de 2.000 ppb, resultou em aumento no consumo de ração. As demais variáveis não foram influenciadas pelos níveis de Cr na dieta. O nível de 500 ppb de Cr na dieta é indicado para aumento da produção de ovos comercializáveis de codornas japonesas em fase de postura mantidas em estresse por calor.The objective was to evaluate the effects of the addition of organic chromium in the diet of Japanese quails in the initial fase of laying, under heat stress. Six hundred quails averaging 63 days old and initial body weight of 158.60 g on high temperature environment (32ºC were used. Diets were based on corn and soybean meal, and supplemented with five levels of chromium (0, 500, 1,000, 1,500, and 2,000 ppb, from chromium-methionine, in replacement with innert material. The experimental design was completely randomized, with 12 experimental units per treatment and ten birds in each experimental unit. The least

  1. Infecção aguda e latente em ovinos inoculados com o herpesvírus bovino tipo 5 (BHV-5 Acute and latent infection in sheep inoculated with bovine herpesvirus type-5 (BHV-5

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    Adriana M. Silva

    1998-07-01

    Full Text Available Infecção experimental de ovinos com o herpesvírus bovino tipo 5 (BHV-5 reproduziu vários aspectos da infecção pelo BHV-5 em bovinos. Inoculação intranasal foi seguida de extensiva replicação viral na cavidade nasal, excreção e transmissão do vírus a outros animais, estabelecimento e reati-vação de latência, e o desenvolvimento de meningoencefalite clínica em um animal. Ovinos inoculados com a amostra brasileira EVI-88 apresentaram hipertermia transitória, hiperemia da mucosa nasal e corrimento nasal de seroso a muco-purulento. Os animais eliminaram vírus em secreções nasais em títulos de até 107,11DICC50/ml por até 16 dias. Um cordeiro apresentou sinais clínicos de encefalite no dia 10 pós-inoculação, sendo sacrificado in extremis no início do dia 13. Infectividade foi detectada em várias regiões do encéfalo desse animal, incluindo os hemisférios anterior e posterior, córtex dorso- e ventro-lateral, ponte, pedúnculo cerebral, cerebelo e bulbo olfatório. Alterações histológicas foram observadas em várias regiões do encéfalo, principalmente no hemisfério anterior, córtex ventro-lateral e pedúnculos cerebrais, e consistiram de meningite mononuclear, manguitos perivasculares, gliose focal, necrose e inclusões intranucleares em neurônios . Quatro ovinos mantidos como sentinelas adquiriram a infecção e eliminaram vírus a partir do final do segundo dia, até 7 dias. Ovinos inoculados com a amostra argentina A663 apresentaram apenas hiperemia e umidecimento da mucosa nasal, embora eliminassem vírus nas secreções nasais por até 15 dias. Tratamento dos animais com dexametasona a partir do dia 50 pós-inoculação provocou reativação da infecção latente e eliminação viral durante até 11 dias por 76,9% (10/13 dos animais inoculados e por 100% (3/3 dos animais sentinela. Esses resultados demonstram que ovinos são susceptíveis à infecção aguda e latente pelo BHV-5 e sugerem que infec

  2. Relato inusitado de micro-organismos latentes em animais: riscos à pesquisa e à saúde dos funcionários? Report on the unusual presence of latent microorganisms in animals: a risk to research and health of employees?

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    Natalino Hajime Yoshinari

    2009-10-01

    Full Text Available Relata-se inusitado achado de micro-organismos, semelhantes às espiroquetas, móveis e de diferentes morfologias e tamanhos, identificados pela microscopia de campo escuro, no sangue de animais do Centro de Bioterismo da Faculdade de Medicina da USP. As bactérias não crescem em meios habituais de cultivo, são pouco coradas pelo Giemsa e derivados da prata, e as provas sorológicas e moleculares foram negativas para Borrelia e Leptospira. A microscopia eletrônica revelou presença de micro-organismos com morfologia de Mycoplasma e, devido à sua mobilidade, sugeriu-se a presença de Mollicutes do gênero Spiroplasma. Visualizaram-se micro-organismos com mesmas características em 15 dos 26 funcionários (57,6% do Centro de Bioterismo da FMUSP; contudo, exames clínicos e laboratoriais indicaram que os indivíduos estavam saudáveis. Estudos adicionais desenvolvidos na Disciplina de Reumatologia da FMUSP mostraram que, aproximadamente, 94% dos pacientes com Síndrome Baggio-Yoshinari (SBY e 20% dos indivíduos normais também exibiam as mesmas estruturas identificadas no Centro de Bioterismo. A microscopia eletrônica realizada com amostras de pacientes com SBY mostrou bactérias que apresentam semelhanças com Mycoplasma, Chlamydia e Bacteroides. Visto que as sorologias e os testes moleculares foram negativos para estes contaminantes e com base em publicações da literatura médica, sugeriu-se que estes agentes infecciosos latentes fossem bactérias na sua apresentação L, que são definidas como bactérias despojadas de parede celular, assumindo, assim, morfologia de Mycoplasma, sendo, na maioria dos casos, inofensivas aos hospedeiros. Concluímos que os "espiroquetídeos" visualizados em animais e funcionários do Centro de Bioterismo seriam bactérias na forma L, não patogênicas, provenientes de contaminantes do meio ambiente, infecções regulares habituais ou oriundos de micro-organismos endógenos da flora saprofítica normal. Ao

  3. Avaliação dos níveis de ruído, luz e calor em máquinas de colheita florestal Evaluation of noise, light and heat levels of forest harvesting machines

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    Luciano J. Minette

    2007-12-01

    Full Text Available Esta pesquisa foi desenvolvida com dados coletados em áreas de colheita de madeira em três empresas do Estado de Minas Gerais; o objetivo geral foi avaliar os níveis de ruído, luz e calor, em máquinas de colheita florestal. Foram avaliados os postos de trabalho das seguintes máquinas: Feller-Buncher, Skidder, Garra-Traçadora, Traçador Mecânico e Carregador Florestal e os níveis de ruído medidos com o uso de um dosímetro, a iluminação através de um luxímetro digital e a exposição ao calor com o IBUTG. Na empresa 1, os dois tratores florestais avaliados enquanto parados emitem o mesmo nível de ruído, possuem luz interna e boas condições térmicas; na empresa 2, para as três máquinas avaliadas o nível de ruído está abaixo do limite recomendado pela NR 15, as cabines possuem luz interna e climatização regulável e na empresa 3 todas as máquinas apresentaram níveis de ruído superiores ao permitido pela legislação brasileira, o carregador florestal e o Mini-skidder apresentaram iluminação inadequada e os índices de temperatura efetiva estão fora da zona de conforto térmico para todas as máquinas. Conclui-se que todas as máquinas utilizadas pela empresa 3 estão em desconformidade ergonômica.This research was developed with data collected in areas of wood harvesting by three companies of the State of Minas Gerais, Brazil. The general objective was to evaluate the level of noise, light and heat of forest harvesting machines. The work stations of the following machines were evaluated: Feller-Buncher, Skidder, Bucking Tongs, Mechanical Bucking and Forest Loader. The noise levels were measured with the use of a dosimeter, the light with a digital luximeter and the heat exposure with the IBUTG. At company 1, the two evaluated forest tractors, while stopped, presented the same level of noise, both had internal lighting and good thermal conditions. At company 2, for the three evaluated machines, the level of noise was

  4. Níveis de lisina digestível em rações, em que se manteve ou não a relação aminoacídica, para frangos de corte de 1 a 21 dias de idade, mantidos em estresse por calor

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    Valerio Sandra Roseli

    2003-01-01

    Full Text Available Dois ensaios foram conduzidos para avaliar os efeitos de níveis de lisina digestível em rações em que se manteve ou não a relação aminoacídica sobre o desempenho de frangos de corte machos de 1 a 21 dias de idade, criados em alta temperatura. O delineamento experimental utilizado em ambos os ensaios foi o inteiramente casualizado. As aves, no ensaio 1, foram distribuídas em cinco tratamentos (0,92; 0,98; 1,04; 1,10 e 1,16% de lisina digestível em ração convencional, oito repetições e dez aves por repetição. No ensaio 2, os frangos foram distribuídos em quatro tratamentos (1,04; 1,10; 1,16 e 1,22% de lisina digestível em rações mantendo a relação aminoacídica, oito repetições e dez aves por repetição. No ensaio 1, os tratamentos influenciaram quadraticamente o ganho de peso e o consumo de ração, que aumentaram até os níveis de 1,14 e 1,09% de lisina, respectivamente. Embora a conversão alimentar tenha melhorado de forma linear, o modelo LRP foi o que melhor se ajustou aos dados, estimando em 1,097% o nível de lisina a partir do qual ocorreu um platô. Não houve efeito dos tratamentos sobre os pesos absolutos do coração, fígado e intestinos, enquanto o peso absoluto da moela aumentou linearmente. O peso absoluto da carcaça aumentou, enquanto os pesos relativos do coração e do fígado reduziram quadraticamente com os tratamentos. No ensaio 2, os tratamentos influenciaram de forma linear crescente o ganho de peso e a conversão alimentar, enquanto o consumo de ração não variou. Os tratamentos influenciaram linearmente o peso absoluto da carcaça, enquanto os pesos absoluto e relativo das vísceras não variaram. Concluiu-se que frangos de corte machos, de 1 a 21 dias de idade, mantidos em estresse por calor, exigem, no mínimo, 1,14 e 1,22% de lisina digestível em ração convencional e em ração em que se manteve a relação aminoacídica, respectivamente.

  5. Ractopamine levels for finishing barrows maintained in heat stress Níveis de ractopamina para suínos machos castrados em terminação mantidos sob estresse por calor

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    Josilene Figueiredo Sanches

    2010-07-01

    Full Text Available The objective of this study was to evaluate performance, quantitative characteristics of carcass, and visceral responses of barrows maintained on heat stress enviroment and fed diets supplemented with ractopamine. It was used 48 animals with initial weight of 67.3 ± 3.8 kg, distributed in a randomized block design with four levels of ractopamine (0, 5, 10 and 20 mg/kg, each one with six replicates with two animals each. The experimental period lasted 28 days. Air temperature was 31.8 ± 2.0ºC, air humidity was 72.6 ± 10.2% and BGHI was 82.7 ± 2.8. Daily feed intake was not affect by the levels of ractopamine but they improved feed conversion and increased daily weight gain and final weight of the animals. The carcass quantitative characteristics were not affected by levels of ractopamine. The weights of the liver and kidneys showed linear increases accordingly to increase of ractopamine levels in the diet whereas weight of other organs and length of small intestine were not affected by supplementation with ractopamine. The optimum level of ractopamine for the best performance of barrows under heat stress is 20 mg/kg and it does not affect the quantitative characteristics of carcass.Avaliaram-se o desempenho, as características quantitativas de carcaça e as respostas viscerais de suínos machos castrados mantidos em ambiente de estresse por calor e alimentados com dietas suplementadas com ractopamina. Foram utilizados 48 animais com peso inicial de 67,3 ± 3,8 kg, distribuídos em delineamento em blocos casualizados, com quatro níveis de ractopamina (0, 5, 10 e 20 mg/kg, cada um com seis repetições de dois animais. O período experimental foi de 28 dias. A temperatura do ar foi de 31,8 ± 2,0ºC, a umidade relativa foi de 72,6 ± 10,2% e índice de temperatura de globo e umidade (ITGU de 82,7 ± 2,8. Os níveis de ractopamina não influenciaram o consumo diário de ração, mas melhoraram a conversão alimentar e aumentaram o ganho di

  6. Determinação do calor de dessorção para materiais têxteis = Determining heat of desorption for textile materials

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    Gracielle Johann

    2010-01-01

    Full Text Available O presente trabalho tem como objetivo o cálculo do calor de dessorção da umidade, durante a secagem de materiais têxteis, utilizando o método de Othmer, que correlaciona a pressão de vapor e o calor latente de vaporização. Foram utilizados dados da literatura para as isotermas de dessorção de dois diferentes tipos de materiais têxteis (sarja e meia-malha. Os resultados obtidos apresentaram a quantidade de energia necessária para a dessorção da umidade ligada à fibra dos materiais têxteis durante sua secagem. À medida que a quantidade de umidade livre diminui, a quantidade de energia requerida ao processo de dessorção aumenta. A equação determinada para a obtenção do calor de dessorção, em função da unidade de equilíbrio, apresentou uma correlação de 0,999, para ambos os materiais têxteis, para indicar qualidade nos parâmetros obtidos. The objective of this paper is to calculate the heat of desorption of moisture during the drying of textile materials, using the Othmer method, which correlates steam pressure and the latent heat ofvaporization. Data from the literature were used for the desorption isotherms of two different textile material types (denim and cotton-elastane. The results obtained presented the amount of energy required for desorption of moisture linked to the fiber of textilematerials during drying. As the amount of free moisture decreases, the amount of energy required for the process of desorption increases. The equation determined to obtain the heat of desorption, as a function of equilibrium moisture, presented a correlation of 0.999 for both textile materials, which indicates quality in the obtained parameters.

  7. Controle genético e tolerância ao estresse de calor em populações híbridas e em cultivares de trigo Genetic control and tolerance to the heat stress in wheat hybrid population and cultivars

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    Moacil Alves de Souza

    2001-10-01

    Full Text Available O objetivo deste trabalho foi obter informações sobre o controle genético da produtividade de grãos de trigo sob condições de estresse de calor, o grau de tolerância ao estresse de calor de algumas cultivares e linhagens e a identificação de populações segregantes promissoras para a obtenção de linhagens adaptadas às condições da região central do Brasil. Foram avaliados 13 parentais e 40 populações provenientes de um dialelo parcial, nas gerações F1 e F2 em condições de campo, em Lavras e Patos de Minas, MG, com as semeaduras feitas no verão (fevereiro e no inverno (maio. Houve diferença de tolerância ao calor entre os parentais e entre as populações híbridas quanto ao caráter produção de grãos, e ambos os efeitos aditivos e não-aditivos foram importantes no controle genético deste caráter na presença ou ausência de calor. Apesar da ocorrência de interações populações x épocas de semeadura, a alta repetibilidade dos efeitos da capacidade geral de combinação permite inferir a possibilidade de acelerar os programas de melhoramento na região, efetuando-se a seleção tanto na época de verão quanto no inverno.The objective of this work was to get information about the genetic control of the grain yield under heat stress conditions, the tolerance of cultivar and the identification of promising segregation populations for selections of lines adapted to the conditions of the central region of Brazil. Thirteen parents and 40 populations in F1 and F2 generations derived by partial diallel crosses were evaluated. The experiments were conducted under field conditions in Lavras and Patos de Minas, MG, Brazil, sowing the seeds in the summertime (February and in the winter (May. There was difference of heat tolerance among parents and hybrid populations for grain yield character, and both additive and non-additive effects were important in the genetic control of grain yield character in the presence or absence

  8. Determinação do calor de dessorção para materiais têxteis - DOI: 10.4025/actascitechnol.v32i1.1025

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    Gracielle Johann

    2009-12-01

    Full Text Available O presente trabalho tem como objetivo o cálculo do calor de dessorção da umidade, durante a secagem de materiais têxteis, utilizando o método de Othmer, que correlaciona a pressão de vapor e o calor latente de vaporização. Foram utilizados dados da literatura para as isotermas de dessorção de dois diferentes tipos de materiais têxteis (sarja e meia-malha. Os resultados obtidos apresentaram a quantidade de energia necessária para a dessorção da umidade ligada à fibra dos materiais têxteis durante sua secagem. À medida que a quantidade de umidade livre diminui, a quantidade de energia requerida ao processo de dessorção aumenta. A equação determinada para a obtenção do calor de dessorção, em função da unidade de equilíbrio, apresentou uma correlação de 0,999, para ambos os materiais têxteis, para indicar qualidade nos parâmetros obtidos.

  9. Stochastic Approximation Methods for Latent Regression Item Response Models

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    von Davier, Matthias; Sinharay, Sandip

    2010-01-01

    This article presents an application of a stochastic approximation expectation maximization (EM) algorithm using a Metropolis-Hastings (MH) sampler to estimate the parameters of an item response latent regression model. Latent regression item response models are extensions of item response theory (IRT) to a latent variable model with covariates…

  10. A thymidine kinase-deleted bovine herpesvirus 5 establishes latent infection but reactivates poorly in a sheep model Recombinante do herpesvírus bovino tipo 5 com deleção na timidina quinase estabelece infecção latente porém reativa ineficientemente em ovinos

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    Gustavo C. Cadore

    2013-03-01

    Full Text Available The ability of thymidine kinase (tk-deleted recombinant bovine herpesvirus 5 (BoHV-5tkΔ to establish and reactivate latent infection was investigated in lambs. During acute infection, the recombinant virus replicated moderately in the nasal mucosa, yet to lower titers than the parental strain. At day 40 post-infection (pi, latent viral DNA was detected in trigeminal ganglia (TG of all lambs in both groups. However, the amount of recombinant viral DNA in TGs was lower (9.7-fold less than that of the parental virus as determined by quantitative real time PCR. Thus, tk deletion had no apparent effect on the frequency of latent infection but reduced colonization of TG. Upon dexamethasone (Dx administration at day 40 pi, lambs inoculated with parental virus shed infectious virus in nasal secretions, contrasting with lack of infectivity in secretions of lambs inoculated with the recombinant virus. Nevertheless, some nasal swabs from the recombinant virus group were positive for viral DNA by PCR, indicating low levels of reactivation. Thus, BoHV-5 TK activity is not required for establishment of latency, but seems critical for efficient virus reactivation upon Dx treatment.A capacidade de um recombinante do herpesvírus bovino tipo 5 com deleção no gene da timidina quinase (BoHV-5tk∆ em estabelecer e reativar infecção latente foi investigada em cordeiros. Durante a infecção aguda, o vírus recombinante replicou na mucosa nasal em títulos moderados, porém menores do que os da cepa parental. Aos 40 dias pós-infecção (pi DNA viral latente foi detectado no gânglio trigêmeo (TG de todos os cordeiros em ambos os grupos. No entanto, a quantidade de DNA do vírus recombinante nos TGs foi 9,7 vezes menor do que do vírus parental, segundo determinação por PCR em tempo real. Assim, a deleção do gene tk (timidina quinase não produziu efeito aparente sobre a frequência da infecção latente, porém reduziu a colonização do TG. Após a

  11. Balanço de energia em vinhedo de 'Niagara Rosada' Energy balance on 'Niagara Rosada' vineyard

    Directory of Open Access Journals (Sweden)

    José Ricardo Macedo Pezzopane

    2003-01-01

    Full Text Available O método do balanço de energia foi utilizado para caracterizar a variação horária do saldo de radiação e dos fluxos de calor latente, sensível e no solo, em vinhedo cultivado com a cultivar NiagaraRosada', conduzida no sistema de espaldeira, em Jundiaí (SP. Além disso, foram determinadas as relações entre o saldo de radiação (SR no vinhedo e a radiação solar global (RG e a partição da energia disponível ao sistema nos fluxos de calor latente (LE, sensível (H e no solo (G. Em um dia característico de período seco, o LE representou 44% do SR e o H, 48%. Em um dia chuvoso, o LE representou 86% do SR e o H, 21%. Em um dia ensolarado, após um período de chuvas, LE e H foram, respectivamente, 68% e 29% do SR. O G foi, em média, 5,7% e 1,3% do SR para as ruas mantidas capinadas e com forro, respectivamente.The energy balance method was used to characterize the hourly variation of the net radiation, latent and sensible fluxes and soil heat flux on a mature vineyard grown at Jundiaí, São Paulo, Brazil. The grapevines, cv. Niagara Rosada, in the vineyard were wrapped to trellis wires, creating compact hedgerows 2 m apart, 1.7 m height and 0.4 wide, with the foliage 1m above the soil surface. Also, the net and incoming radiation relationships and the partioning of the available energy to the system into latent and heat flux, and soil heat flux were determined for the vineyard. During a sunny day (dry period the latent heat flux was 44% of the net radiation and the sensible heat flux, 48%. However during a rainy day, the latent heat flux was 86% of the net radiation and the sensible heat flux, 21%. During a sunny day, after the occurrence of rain, the latent and sensible heat fluxes were, respectively, 68% and 29% of the net radiation. The soil heat flux was 5.7 an 1.3% of the net radiation, for bare soil and mulched rows, respectively.

  12. Simulação da transferência de calor na articulação do joelho em modelo animal para condições de aquecimento e resfriamento

    OpenAIRE

    2011-01-01

    A aplicação terapêutica de calor e de frio é amplamente utilizada na prática clínica da fisioterapia, sendo especialmente relevante no tratamento de lesões do sistema musculoesquelético (osso, ligamento, músculo e tendão). Para que os benefícios decorrentes dessas terapias possam ser alcançados é necessário, entretanto, que o tecido alvo atinja uma faixa ótima de temperatura. Temperaturas fora da faixa terapêutica recomendada podem promover tratamentos ineficazes e até mesmo dano térmico ao t...

  13. Sinterização de filmes finos de LiNbO3 em forno microondas: estudo da influência da direção do fluxo de calor Sintering of LiNbO3 thin films in microwave furnace: study of the influence of the heat flow direction

    Directory of Open Access Journals (Sweden)

    N. S. L. S. Vasconcelos

    2004-06-01

    Full Text Available Filmes finos de LiNbO3 foram preparados pelo método dos precursores poliméricos e depositados por "spin coating" sobre substratos de safira (0001. Os filmes foram tratados em forno microondas doméstico a 400 ºC por 15 e 20 min. Um material com alta perda dielétrica (susceptor de SiC foi usado para absorver energia das microondas e transformá-la em calor. Este calor foi transferido para o filme a fim de promover a sua cristalização. O susceptor foi posicionado acima do filme ou embaixo do substrato. Desta forma, a influência da direção do fluxo de calor na cristalização das amostras foi verificada. Os filmes foram caracterizados por difração de raios X, microscopia de força atômica e espectrofotometria (transmitância na região UV-visível e o índice de refração foi determinado por elipsometria. O crescimento epitaxial foi observado para o filme com susceptor posicionado embaixo do substrato. Verificou-se que os grãos apresentaram crescimento aleatório quando o susceptor foi posicionado acima do filme. Os filmes apresentaram-se relativamente densos, homogêneos e lisos, com boas propriedades ópticas.LiNbO3 thin films were prepared using a polymeric precursor solution deposited by spin coating on (0001 sapphire substrate. Heat treatment of the films was carried out in a microwave oven at 400 ºC for 15 and 20 min. A SiC susceptor (material with high dielectric loss was used to absorb microwave energy and transfer the heat to the film in order to promote crystallization. The susceptor was placed above the film or below the substrate. Thus, the influence of the heat flux direction on the sample crystallization was verified. The films were characterized by X-ray diffraction, atomic force microscopy and spectrophotometry (transmittance in the UV-Visible region and the refractive index was determined with an ellipsometer. The epitaxial growth was observed for the film with the susceptor placed below the substrate. Random growth

  14. Carnot to Clausius: Caloric to Entropy

    Science.gov (United States)

    Newburgh, Ronald

    2009-01-01

    This paper discusses how the Carnot engine led to the formulation of the second law of thermodynamics and entropy. The operation of the engine is analysed both in terms of heat as the caloric fluid and heat as a form of energy. A keystone of Carnot's thinking was the absolute conservation of caloric. Although the Carnot analysis was partly…

  15. Análise computacional do fenômeno de transferência de calor em paredes divisórias do tipo dry wall Computational analysis of the heat transfer through cold-formed steel frame panel under fire condition

    Directory of Open Access Journals (Sweden)

    Maurício C. Alves

    2007-06-01

    Full Text Available O presente trabalho visa a fornecer uma contribuição ao estudo dos perfis formados a frio sob altas temperaturas, em conseqüência da deflagração de um incêndio. Especificamente, abordam-se assuntos inerentes ao fenômeno da transferência de calor em paredes do tipo steel frame - dry wall com ou sem isolamento térmico na cavidade. Para tanto, propõem-se modelos computacionais capazes de fornecer, com certa precisão, o valor de temperatura em qualquer ponto do sistema estudado. Dessa forma, é possível, então, traçar configurações de distribuição de temperatura (uniforme ou não-uniforme na seção transversal dos montantes que constituem o painel, fornecendo subsídios para análise de estabilidade e pós-flambagem dos elementos estruturais em questão. As simulações numéricas de transferência de calor são efetuadas com auxílio dos programas computacionais ABAQUS e SAFIR, ambos baseados no método dos elementos finitos.The present work aims to give a contribution to the study of cold-formed steel members under fire condition. Specifically, the heat transfer in light steel framed walls with or without thermal insulation was studied. For this, computational models are applied to obtain, with acceptable precision, the values of temperature in any position of the structural system. In this way, it will be possible to describe the temperature distribution (uniform or non-uniform over the cross-section of the studs that constitute the panel, giving subsidies for stability and pos-buckling analyses of the structural members. The numerical simulations of heat transfer are developed with the aid of computational programs ABAQUS and SAFIR, both based on the finite element method.

  16. Caloric curve of star clusters.

    Science.gov (United States)

    Casetti, Lapo; Nardini, Cesare

    2012-06-01

    Self-gravitating systems, such as globular clusters or elliptical galaxies, are the prototypes of many-body systems with long-range interactions, and should be the natural arena in which to test theoretical predictions on the statistical behavior of long-range-interacting systems. Systems of classical self-gravitating particles can be studied with the standard tools of equilibrium statistical mechanics, provided the potential is regularized at small length scales and the system is confined in a box. The confinement condition looks rather unphysical in general, so that it is natural to ask whether what we learn with these studies is relevant to real self-gravitating systems. In order to provide an answer to this question, we consider a basic, simple, yet effective model of globular clusters: the King model. This model describes a self-consistently confined system, without the need of any external box, but the stationary state is a nonthermal one. In particular, we consider the King model with a short-distance cutoff on the interactions, and we discuss how such a cutoff affects the caloric curve, i.e., the relation between temperature and energy. We find that the cutoff stabilizes a low-energy phase, which is absent in the King model without cutoff; the caloric curve of the model with cutoff turns out to be very similar to that of previously studied confined and regularized models, but for the absence of a high-energy gaslike phase. We briefly discuss the possible phenomenological as well as theoretical implications of these results.

  17. Aspectos virológicos e clínico-patológicos da infecção genital aguda e latente pelo herpesvírus bovino tipo 1.2 em bezerras infectadas experimentalmente Virological and clinico-pathological features of acute vulvovaginitis and latent infection by bovine herpesvirus 1.2 in heifers experimentally infected

    Directory of Open Access Journals (Sweden)

    Andréia Henzel

    2008-03-01

    Full Text Available A infecção genital de vacas pelo herpesvírus bovino tipo 1.2 (BoHV-1.2 pode resultar em vulvovaginite e infertilidade temporária. Após a infecção aguda, o BoHV-1 estabelece infecção latente, que pode cursar com episódios periódicos de reativação. O presente trabalho descreve os aspectos virológicos e clínico-patológicos da vulvovaginite aguda e infecção latente resultantes da inoculação de bezerras com uma amostra de BoHV-1.2 isolada de casos de balanopostite em touros. A inoculação do vírus em quatro bezerras pela via genital (10(8.1TCID50/animal resultou em replicação viral na mucosa genital e no desenvolvimento de vulvovaginite moderada a severa. Os animais inoculados excretaram o vírus nas secreções genitais até o dia 10 pós-inoculação (p.i. com título máximo de 10(7.3TCID50/mL. Foram observados congestão e edema da mucosa vulvovestibular, e formação de pequenas vesículas e pústulas. Durante a progressão clínica, as vesículas e pústulas aumentaram de tamanho e eventualmente se tornaram coalescentes e recobertas por um exsudato fino de coloração amarelada. Estes sinais foram observados a partir do dia 2 p.i. e aumentaram progressivamente de severidade até os dias 5-8 p.i. A administração de dexametasona no dia 55 p.i. resultou em excreção viral nas secreções genitais dos quatro animais por até 10 dias. A reativação da infecção latente foi acompanhada de recrudescência clínica, porém com sinais menos severos e com menor duração do que na infecção aguda. O DNA viral latente foi detectado por PCR, aos 36 dias pós-reativação (p.r., nos seguintes tecidos: gânglio sacrais: pudendo (4/4; genitofemoral e retal caudal (3/4 e obturador (4/4 e em alguns linfonodos regionais. Estes resultados demonstram que o isolado SV-56/90 é virulento para fêmeas soronegativas, após inoculação genital, e pode ser utilizado em estudos de patogenia e de desafio vacinal.Venereal infection of heifers

  18. Use of the heat dissipation method for sap flow measurement in citrus nursery trees1 Uso do método de dissipação de calor para a medição do fluxo de seiva em mudas cítricas

    Directory of Open Access Journals (Sweden)

    Eduardo Augusto Girardi

    2010-12-01

    Full Text Available Sap flow could be used as physiological parameter to assist irrigation of screen house citrus nursery trees by continuous water consumption estimation. Herein we report a first set of results indicating the potential use of the heat dissipation method for sap flow measurement in containerized citrus nursery trees. 'Valencia' sweet orange [Citrus sinensis (L. Osbeck] budded on 'Rangpur' lime (Citrus limonia Osbeck was evaluated for 30 days during summer. Heat dissipation probes and thermocouple sensors were constructed with low-cost and easily available materials in order to improve accessibility of the method. Sap flow showed high correlation to air temperature inside the screen house. However, errors due to natural thermal gradient and plant tissue injuries affected measurement precision. Transpiration estimated by sap flow measurement was four times higher than gravimetric measurement. Improved micro-probes, adequate method calibration, and non-toxic insulating materials should be further investigated.O fluxo de seiva poderia ser utilizado como parâmetro fisiológico para fomentar a irrigação de mudas cítricas em cultivo protegido pela estimação do consumo contínuo de água. Neste trabalho, reportam-se os primeiros resultados, indicando o uso potencial e as limitações iniciais do método de dissipação de calor para medição do fluxo de seiva em mudas cítricas em recipientes. Mudas de laranjeira-doce 'Valência' [Citrus sinensis (L. Osbeck] enxertadas sobre limoeiro 'Cravo' (Citrus limonia Osbeck foram avaliadas por 30 dias, durante o verão. Sondas de dissipação de calor e sensores do tipo termopar foram construídos a partir de materiais prontamente disponíveis e de baixo custo para favorecer o acesso ao método por viveiristas. O fluxo de seiva apresentou alta correlação com a temperatura do ar dentro da estufa telada. Contudo, erros inerentes ao gradiente térmico natural e a injúrias nos tecidos do caule afetaram a

  19. Análise paramétrica da injeção de vapor e solvente em reservatórios de óleo pesado

    OpenAIRE

    Galvão, Edney Rafael Viana Pinheiro

    2012-01-01

    Uma porção significativa das reservas de hidrocarbonetos atualmente existentes no mundo é formada por óleos pesados. Dentre os métodos térmicos utilizados para a recuperação desse tipo de recurso, a Injeção Contínua de Vapor tem se constituído como uma das principais alternativas economicamente viáveis. No Brasil, essa tecnologia é largamente utilizada pela Petrobras em campos localizados na região Nordeste. O calor latente transportado pelo vapor aquece o óleo do reservatório,...

  20. Análise de viabilidade de injeção de fluidos alternativos ao vapor em reservatórios de óleo pesado

    OpenAIRE

    Rodrigues, Marcos Allyson Felipe

    2012-01-01

    Muitas das reservas de hidrocarbonetos existentes em todo o mundo são formadas por óleos pesados (°API entre 10 e 20). Além disso, vários campos de óleo pesado estão maduros e, portanto, oferecem grandes desafios para a indústria do petróleo. Entre os métodos térmicos utilizados para recuperar estes recursos, a injeção de vapor tem sido a principal alternativa economicamente viável. O calor latente transportado por meio de vapor aquece o reservatório, reduzindo a viscosidade do...

  1. Caloric beverage consumption patterns in Mexican children

    Directory of Open Access Journals (Sweden)

    Rivera Juan A

    2010-10-01

    Full Text Available Abstract Background Mexico has seen a very steep increase in child obesity level. Little is known about caloric beverage intake in this country as well as all other countries outside a few high income countries. This study examines overall patterns and trends in all caloric beverages from two nationally representative surveys from Mexico. Methods The two nationally representative dietary intake surveys (1999 and 2006 from Mexico are used to study caloric beverage intake in 17, 215 children. The volume (ml and caloric energy (kcal contributed by all beverages consumed by the sample subjects were measured. Results are weighted to be nationally representative. Results The trends from the dietary intake surveys showed very large increases in caloric beverages among pre-school and school children. The contribution of whole milk and sugar-sweetened juices was an important finding. Mexican pre-school children consumed 27.8% of their energy from caloric beverages in 2006 and school children consumed 20.7% of their energy from caloric beverages during the same time. The three major categories of beverage intake are whole milk, fruit juice with various sugar and water combinations and carbonated and noncarbonated sugared-beverages. Conclusion The Mexican government, greatly concerned about obesity, has identified the large increase in caloric beverages from whole milk, juices and soft drinks as a key target and is initiating major changes to address this problem. They have already used the data to shift 20 million persons in their welfare and feeding programs from whole to 1.5% fat milk and in a year will shift to nonfat milk. They are using these data to revise school beverage policies and national regulations and taxation policies related to an array of less healthful caloric beverages.

  2. Estudo da aplicabilidade de testes serológicos no diagnóstico de tuberculose em Portugal : o caso particular da tuberculose latente

    OpenAIRE

    Ferreira, Carina Manuela Pinto

    2008-01-01

    A Organização Mundial da Saúde estima que cerca de um terço da população mundial (2 biliões de pessoas) esteja infectada com Mycobacterium tuberculosis, na sua maioria com Tuberculose (TB) latente, representando um importante reservatório de reactivação da doença. Calcula-se que cerca de 10% das pessoas com TB latente desenvolve TB activa a um dado momento da vida, sendo que na maioria das situações acontece nos dois anos após a infecção. Torna-se portanto imperativo identificar as pessoas...

  3. Análise da redistribuição de calor com agentes inalatórios, em ratos submetidos a laparotomia e pneumoperitônio, através da termografia infravermelha Análisis de la redistribución de calor con agentes inhalatorios, en ratones sometidos a laparotomia y pneumoperitonio, a través de termografia infraroja Analysis of heat loss using inhalation agents in rats subjected to laparotomy and increased intra-abdominal pressure, using digital infrared thermal image

    Directory of Open Access Journals (Sweden)

    Daniel Colman

    2002-06-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: A Anestesiologia envolve o manuseio de situações inerentes ao ato anestésico e operatório que cursam com o desequilíbrio da homeostase térmica do paciente, ocasionando efeitos fisiológicos deletérios. O presente estudo objetiva qualificar e quantificar os fenômenos de redistribuição térmica em ratos submetidos à anestesia inalatória, durante a indução, e em situações cirúrgicas de laparotomia e pneumoperitônio. MÉTODO: Foram utilizados 90 ratos, que foram submetidos à anestesia inalatória, distribuídos em três grupos, em que foram utilizados: halotano, isoflurano e sevoflurano. Em cada grupo houve divisão em outros três sub-grupos: I - controle, II - laparotomia mediana com exposição de alças intestinais; III - pneumoperitônio de 15 mmHg. A análise termodinâmica realizou-se de duas formas: através da temperatura central esofágica e da imagem digital térmica infravermelha. RESULTADOS: Não houve diferença significativa em relação aos anestésicos inalatórios entre os grupos I e II em relação a perda de calor. Em relação ao grupo III, houve diferença entre o isoflurano e o sevoflurano, sendo o isoflurano o anestésico responsável pela maior perda de temperatura no animal. CONCLUSÕES: O sevoflurano foi o agente anestésico inalatório que determinou menor perda de calor frente ao pneumoperitônio, em relação ao isoflurano e halotano.JUSTIFICATIVA Y OBJETIVOS: La Anestesiología envuelve el manoseo de situaciones inherentes al acto anestésico y operatorio que cursan con el desequilibrio de la homeóstasis térmica del paciente, ocasionando efectos fisiológicos deletéreos. El presente estudio objetiva calificar y cuantificar los fenómenos de redistribución térmica en ratones sometidos a anestesia inhalatoria, durante la inducción, y en situaciones quirúrgicas de laparotomia y pneumoperitonio. MÉTODO: Fueron utilizados 90 ratones, sometidos a anestesia inhalatoria

  4. Intake of calorically sweetened beverages and obesity

    DEFF Research Database (Denmark)

    Olsen, N J; Heitmann, B L

    2009-01-01

    The prevalence of obesity has increased in the past 30 years, and at the same time a steep increase in consumption of soft drinks has been seen. This paper reviews the literature for studies on associations between intake of calorically sweetened beverages and obesity, relative to adjustment...... studies were identified. The majority of the prospective studies found positive associations between intake of calorically sweetened beverages and obesity. Three experimental studies found positive effects of calorically sweetened beverages and subsequent changes in body fat. Two experimental studies did...... not find effects. Eight prospective studies adjusted for energy intake. Seven of these studies reported associations that were essentially similar before and after energy adjustment. In conclusion, a high intake of calorically sweetened beverages can be regarded as a determinant for obesity. However...

  5. Uma medida de calor específico sem calorímetro

    Directory of Open Access Journals (Sweden)

    Mattos Cristiano

    2003-01-01

    Full Text Available Várias técnicas têm sido desenvolvidas para se obter o calor específico de sólidos e líquidos, incluindo a construção de experimentos de baixo custo para o ensino médio. Neste trabalho propomos uma maneira simples de se obter o calor específico de sólidos e líquidos. Por meio de curvas de calibração de resfriamento podemos estimar graficamente a perda de calor do sistema para sua vizinhança, e medir o calor específico do alumínio. Esta aproximação permite introduzir uma discussão sobre o processo dinâmico da troca de calor entre dos corpos.

  6. Stochastic Approximation Methods for Latent Regression Item Response Models. Research Report. ETS RR-09-09

    Science.gov (United States)

    von Davier, Matthias; Sinharay, Sandip

    2009-01-01

    This paper presents an application of a stochastic approximation EM-algorithm using a Metropolis-Hastings sampler to estimate the parameters of an item response latent regression model. Latent regression models are extensions of item response theory (IRT) to a 2-level latent variable model in which covariates serve as predictors of the…

  7. Asymmetry Dependence of the Nuclear Caloric Curve

    CERN Document Server

    McIntosh, Alan B; Cammarata, Paul; Hagel, Kris; Heilborn, Lauren; Kohley, Zachary; Mabiala, Justin; May, Larry W; Marini, Paola; Raphelt, Andrew; Souliotis, George A; Wuenschel, Sara; Zarrella, Andrew; Yennello, Sherry J

    2012-01-01

    A basic feature of the nuclear equation of state is not yet understood: the dependence of the nuclear caloric curve on the neutron-proton asymmetry. Predictions of theoretical models differ on the magnitude and even the sign of this dependence. In this work, the nuclear caloric curve is examined for fully reconstructed quasi-projectiles around mass A=50. The caloric curve extracted with the momentum quadrupole fluctuation thermometer shows that the temperature varies linearly with quasi-projectile asymmetry (N-Z)/A. An increase in asymmetry of 0.15 units corresponds to a decrease in temperature on the order of 1 MeV. These results also highlight the importance of a full quasi-projectile reconstruction in the study of thermodynamic properties of hot nuclei.

  8. Caloric density of Loricariichthys platymetopon (Osteichthyes, Loricariidae in the Upper Paraná River floodplain, Brazil

    Directory of Open Access Journals (Sweden)

    Daniela Aparecida Garcia

    2010-10-01

    Full Text Available This study analyzed the muscle energy content (caloric density of L. platymetopon captured at different sites of the Upper Paraná River floodplain, and potential relationships between the content and various environmental variables (water temperature, oxygen dissolved in water, food availability, relative numeric abundance and biological variables (body size and reproductive cycle. Quarterly samplings from September 2006 to June 2007 in the lakes and rivers resulted in a sample of 739 specimens, whose muscle caloric density was determined using a calorimeter. Differences between the caloric averages of the males and females and among the different stages of gonadal development were not significant. Caloric density varied over time and space, with two seasonal variation trends. The intensity of the correlation between the caloric density and each environmental variable, as well as the type of correlation, varied according to the sampled site. Body size and reproductive cycle were not correlated with caloric density.Este estudo analisou o conteúdo de energia (densidade calórica de L. platymetopon capturados em diferentes locais da planície alagável do Alto Rio Paraná, e potenciais relações entre este conteúdo e várias variáveis ambientais (temperatura da água, oxigênio dissolvido na água, disponibilidade de alimento, abundância relativa numérica e variáveis biológicas (tamanho corpóreo e ciclo reprodutivo. Coletas trimestrais, de setembro/2006 a junho/2007, em lagos e rios, resultaram em uma amostra de 739 espécimes, cuja densidade calórica muscular foi determinada através de calorímetro. Diferenças entre as médias calóricas de machos e fêmeas e entre os estádios de desenvolvimento gonadal não foram significativas Densidade calórica variou sazonal e espacialmente, com duas tendências de variação sazonal. A intensidade da correlação entre densidade calórica e cada variável e cada variável ambiental, assim como

  9. New developments in caloric materials for cooling applications

    Science.gov (United States)

    Crossley, S.; Mathur, N. D.; Moya, X.

    2015-06-01

    Caloric materials are in the spotlight as candidates for future environmentally friendly cooling technologies. We describe stimulating recent developments in the three caloric strands that are now being studied collectively, namely magnetocaloric, electrocaloric and mechanocaloric (elastocaloric or barocaloric) effects.

  10. New developments in caloric materials for cooling applications

    OpenAIRE

    Crossley, S.; Mathur, N. D.; Moya, X.

    2015-01-01

    Caloric materials are in the spotlight as candidates for future environmentally friendly cooling technologies. We describe stimulating recent developments in the three caloric strands that are now being studied collectively, namely magnetocaloric, electrocaloric and mechanocaloric (elastocaloric or barocaloric) effects.

  11. Controlling for Latent Homophily in Social Networks through Inferring Latent Locations

    CERN Document Server

    Shalizi, Cosma Rohilla

    2016-01-01

    Social influence cannot be identified from purely observational data on social networks, because such influence is generically confounded with latent homophily, i.e., with a node's network partners being informative about the node's attributes and therefore its behavior. We show that {\\em if} the network grows according to either a community (stochastic block) model, or a continuous latent space model, then latent homophilous attributes can be consistently estimated from the global pattern of social ties. Moreover, these estimates are informative enough that controlling for them allows for unbiased and consistent estimation of social-influence effects in additive models. For community models, we also provide bounds on the finite-sample bias. These are the first results on the consistent estimation of social-influence effects in the presence of latent homophily, and we discuss the prospects for generalizing them.

  12. Latent Period of Relaxation.

    Science.gov (United States)

    Kobayashi, M; Irisawa, H

    1961-10-27

    The latent period of relaxation of molluscan myocardium due to anodal current is much longer than that of contraction. Although the rate and the grade of relaxation are intimately related to both the stimulus condition and the muscle tension, the latent period of relaxation remains constant, except when the temperature of the bathing fluid is changed.

  13. Simulação Monte Carlo com Repesagem Aplicada ao Calor Específico de Sólidos

    Directory of Open Access Journals (Sweden)

    Silva Roberto da

    2002-01-01

    Full Text Available Apresenta-se uma estimativa numérica para a contribuição das vibrações da rede para o calor específico de um sólido cristalino. O método Monte Carlo é utilizado tanto em sua forma original quanto em sua versão mais moderna, que emprega a técnica da repesagem para extrair mais informações de cada simulação. Mostra-se como obter curvas contínuas para grandezas como a energia e o calor específico em função da temperatura a partir de simulação feita em apenas uma temperatura. Os resultados analíticos são incluídos para facilitar a comparação com os resultados da simulação.

  14. Latent myofascial trigger points.

    Science.gov (United States)

    Ge, Hong-You; Arendt-Nielsen, Lars

    2011-10-01

    A latent myofascial trigger point (MTP) is defined as a focus of hyperirritability in a muscle taut band that is clinically associated with local twitch response and tenderness and/or referred pain upon manual examination. Current evidence suggests that the temporal profile of the spontaneous electrical activity at an MTP is similar to focal muscle fiber contraction and/or muscle cramp potentials, which contribute significantly to the induction of local tenderness and pain and motor dysfunctions. This review highlights the potential mechanisms underlying the sensory-motor dysfunctions associated with latent MTPs and discusses the contribution of central sensitization associated with latent MTPs and the MTP network to the spatial propagation of pain and motor dysfunctions. Treating latent MTPs in patients with musculoskeletal pain may not only decrease pain sensitivity and improve motor functions, but also prevent latent MTPs from transforming into active MTPs, and hence, prevent the development of myofascial pain syndrome.

  15. Epigenetic regulation of caloric restriction in aging

    Directory of Open Access Journals (Sweden)

    Daniel Michael

    2011-08-01

    Full Text Available Abstract The molecular mechanisms of aging are the subject of much research and have facilitated potential interventions to delay aging and aging-related degenerative diseases in humans. The aging process is frequently affected by environmental factors, and caloric restriction is by far the most effective and established environmental manipulation for extending lifespan in various animal models. However, the precise mechanisms by which caloric restriction affects lifespan are still not clear. Epigenetic mechanisms have recently been recognized as major contributors to nutrition-related longevity and aging control. Two primary epigenetic codes, DNA methylation and histone modification, are believed to dynamically influence chromatin structure, resulting in expression changes of relevant genes. In this review, we assess the current advances in epigenetic regulation in response to caloric restriction and how this affects cellular senescence, aging and potential extension of a healthy lifespan in humans. Enhanced understanding of the important role of epigenetics in the control of the aging process through caloric restriction may lead to clinical advances in the prevention and therapy of human aging-associated diseases.

  16. Colapso pelo calor esforço induzido: reconhecimento para salvar vidas e tratamento imediato em instalações atléticas Choque térmico relacionado con el ejercício: reconocimiento y tratamiento locales para salvar vidas Exertional heat stroke: life-saving recognition and onsite treatment in athletic settings

    Directory of Open Access Journals (Sweden)

    2005-12-01

    Full Text Available O prognóstico do colapso pelo calor esforço induzido depende do produto do tempo de duração em que a temperatura central ficou elevada e do grau da elevação. O atleta com EHS que tem pronta descoberta e que é resfriado de maneira eficiente, muito provavelmente irá sobreviver ao episódio com pouco ou nenhum efeito residual. Em contraste, o atleta com apresentação atrasada para o tratamento, especialmente se a área sob a curva de resfriamento for > 60 graus-minuto (centígrados terá um curso complicado e geralmente fatal. Os métodos de condução do resfriamento com imersão em gelo ou água gelada ou envolvimento em toalhas com água gelada proporcionarão uma rápida e consistente redução da temperatura de todo o corpo, que irá salvar tanto os órgãos quanto a vida. O reconhecimento depende em alto grau da suspeita por parte dos próprios atletas, treinadores e pessoal médico local. Em condições de alto risco, os atletas devem se supervisionar, procurando por mudanças sutis que podem ser sinais de EHS.El pronóstico del choque térmico (CT relacionado con el ejercicio depende del producto del periodo de tiempo en que la temperatura central se mantenga elevada y de la magnitud de esta elevación. El atleta con CT que sea diagnosticado y sea rápida y eficientemente refrescado probablemente sobrevivirá al episodio con ninguna o pocas complicaciones. Por otra parte aquel atleta que halla tenido un inicio tardío en el tratamiento con una área por debajo de la curva mayor de 60 grados-minuto (centigrados tendrá complicaciones y de seguro una evolución fatal. Los métodos de enfriamiento con hielo o inmersión en agua fría o toallas con agua helada en rotación permiten una reducción consistente y rápida de la temperatura corporal capaz de preservar los órganos y la vida. El reconocimiento depende del elevado grado de sospecha por parte de los atletas, técnicos y personal de apoyo médico. En condiciones de alto riesgo

  17. Latent fingerprint matching.

    Science.gov (United States)

    Jain, Anil K; Feng, Jianjiang

    2011-01-01

    Latent fingerprint identification is of critical importance to law enforcement agencies in identifying suspects: Latent fingerprints are inadvertent impressions left by fingers on surfaces of objects. While tremendous progress has been made in plain and rolled fingerprint matching, latent fingerprint matching continues to be a difficult problem. Poor quality of ridge impressions, small finger area, and large nonlinear distortion are the main difficulties in latent fingerprint matching compared to plain or rolled fingerprint matching. We propose a system for matching latent fingerprints found at crime scenes to rolled fingerprints enrolled in law enforcement databases. In addition to minutiae, we also use extended features, including singularity, ridge quality map, ridge flow map, ridge wavelength map, and skeleton. We tested our system by matching 258 latents in the NIST SD27 database against a background database of 29,257 rolled fingerprints obtained by combining the NIST SD4, SD14, and SD27 databases. The minutiae-based baseline rank-1 identification rate of 34.9 percent was improved to 74 percent when extended features were used. In order to evaluate the relative importance of each extended feature, these features were incrementally used in the order of their cost in marking by latent experts. The experimental results indicate that singularity, ridge quality map, and ridge flow map are the most effective features in improving the matching accuracy.

  18. Determinação da tensão de água em solo agrícola usando um sensor de dissipação de calor Soil water evaluation in agricultural soil using a heat dissipation sensor

    Directory of Open Access Journals (Sweden)

    Carlos Alberto da Silva Oliveira

    1999-08-01

    Full Text Available Um estudo foi realizado sob condições de laboratório e de campo objetivando avaliar um sensor de solo utilizado para determinação da temperatura e da tensão da água no solo. Devido à solubilidade do gesso, material poroso utilizado na fabricação dos sensores, houve redução em área da seção transversal e volume, e aumento da porosidade efetiva desses sensores, em relação aos valores observados antes do início dos testes. Os valores médios da temperatura observados com os sensores foram praticamente iguais aos observados com um termômetro de referência com precisão de 0,1°C. Quando sensores saturados foram instalados a 5 cm de profundidade em um solo franco-argilo-siltoso secado ao ar, em relação a valores de Delta T, o tempo de resposta do sensor à secagem foi um pouco superior a 24 horas. Valores de Delta T observados, tanto no laboratório quanto no campo, apresentaram maior variabilidade na faixa representativa de solo seco, em comparação com o solo úmido. Sob condições de campo, não houve diferença estatística (teste F; 5% entre as médias de Delta T obtidas com os sensores de dissipação de calor instalados a 10 cm de profundidade e as médias de tensão obtidas com tensiômetros e transformadas para Delta T.A study was carried out under laboratory and field conditions to evaluate a type of soil sensor used to measure temperature and soil water matric potential. Due to gypsum solubility, porous media used to make the sensor, there was cross sectional area and volume decrease and sensor effective porosity increase in comparison with values obtained prior to the tests. Temperature average values obtained with the sensor were similar to the ones obtained with a reference thermometer having 0.1°C accuracy. Regarding to Delta T values, sensor response time was a little higher than 24 hours when saturated sensors were installed 5 cm deep inside an air dry silty clay loam. Under lab and field conditions observed

  19. Sífilis latente

    OpenAIRE

    Arévalo, Jose David

    2012-01-01

    Trabajo leído por su autor en la Academia Nacional de Medicina, el día 20 de mayo de 1948. La sífilis Latente es aquella en que el organismo se ha defendido biológicamente sin ningún tratamiento, En la sífilis latente hay que distinguir: la latencia clínica, la latencia serológica y la latencia patológica.

  20. Conservación por calor

    OpenAIRE

    Cobos García, Angel; Díaz Rubio, Olga

    2011-01-01

    Esta unidade didáctica denominada Conservación por calor forma parte da materia «Tecnoloxía do procesado de alimentos» que se impartirá no primeiro semestre do 2º curso do Grao en Nutrición Humana e Dietética. A materia estrutúrase en diferentes unidades didácticas, tratando cada unha delas as diferentes tecnoloxías de procesado dos alimentos, tanto de conservación coma de transformación. A presente unidade didáctica aborda a conservación dos alimentos por calor. Este método permite destruír ...

  1. Transferencia de calor a lechos empacados

    OpenAIRE

    Beltrán Feged, Alvaro; Bonilla Melendez, Alberto; Cancelado Arias, Miguel

    2012-01-01

    Consideremos el lecho de solidos granulados de la figura 1.El lecho esta a una temperatura u (z,t), y tiene un calor especifico  cs, que se toma constante. z es la altura del lecho, y t es el tiempo. A este lecho entran G unidades de masa de fluido por unidad de tiempo y de área de sección de lecho(1)(2)

  2. Quantificação da ilha de calor de curitiba considerando aspectos de estabilidade atmosférica

    Directory of Open Access Journals (Sweden)

    Eduardo Krüger

    2015-12-01

    Full Text Available RESUMO A relação entre crescimento urbano e o surgimento de ilhas de calor urbanas, ou seja, diferenças climáticas entre a área urbana e as áreas rurais no entorno, é demonstrada por diversos autores e em diferentes regiões climáticas. Em Curitiba, a população saltou de aproximadamente 600.000 habitantes para um milhão e meio em três décadas. O objetivo do presente trabalho é propor uma metodologia de análise da ilha de calor urbana de Curitiba (25º25'40"S, 49º16'23"W, 934m acima do nível do mar. A cidade está localizada em região de clima subtropical de altitude; o monitoramento climático foi conduzido segundo uma série anual, entre dezembro de 2011 e fevereiro de 2013, utilizando um par de estações meteorológicas dentro e fora (perifericamente da mancha urbana de Curitiba. De modo a minimizar possíveis influências atmosféricas na análise, foi feita a classificação dos dias de medição por classes de estabilidade atmosférica segundo o método de Pasquill-Gifford-Turner (PGT, procedendo-se à análise para dias com maior estabilidade atmosférica. Como complemento à análise, adota-se um modelo de conforto desenvolvido para Curitiba a partir de uma extensa pesquisa de sensação e percepção térmicas em espaços abertos, de modo a verificar o efeito integrado das diversas variáveis climáticas em termos de percentuais de horas em frio, conforto e calor e suas variações dentro e fora da área urbana. Em Curitiba, a ilha de calor urbana pode ser benéfica durante o inverno, porém trazendo consequências em termos de excesso de calor em ambientes internos no verão.

  3. Trombose induzida pelo calor endovenoso: relato de dois casos tratados com rivaroxabana e revisão da literatura

    Directory of Open Access Journals (Sweden)

    Walter Junior Boim de Araujo

    2016-01-01

    Full Text Available Resumo Define-se trombose induzida pelo calor endovenoso como a propagação do trombo a partir de uma veia superficial em direção a uma veia mais profunda. Em geral, é considerada clinicamente insignificante quando não há propagação do trombo para o sistema venoso profundo. Essa condição pode ser tratada com terapia anticoagulante, embora a observação pareça ser suficiente, principalmente para graus menores. Neste estudo, relatamos dois casos de trombose induzida pelo calor endovenoso que teriam indicação de heparina de baixo peso molecular até a resolução do quadro. Porém, optou-se pelo uso da rivaroxabana (15 mg de 12 em 12h, com resolução completa do trombo em 4 semanas (caso 1 e em 7 dias (caso 2. A rivaroxabana pode ser uma alternativa promissora no tratamento da trombose induzida pelo calor endovenoso avançada, pela simplicidade da posologia, sem comprometimento da eficácia ou da segurança. São necessários estudos prospectivos, randomizados e controlados que possibilitem melhor entendimento da condição e o desenvolvimento de recomendações mais definitivas sobre opções de prevenção e tratamento.

  4. Use of non-caloric edulcorants in children

    Directory of Open Access Journals (Sweden)

    Calzada León Raúl

    2014-07-01

    Full Text Available We analyze the health normativity for the denomination of non caloric edulcorants in Mexico, and the authorization for the use of natural and synthetic non caloric edulcorants in newborn and until puberty. Special emphasis was given to the consecutive points of safety required in order to assure that they are free of secondary effects. For each non caloric edulcorant available in Mexico, we looked into the studies which mention their side effects in terms of growth and overall.

  5. Latent tuberculosis infection.

    Science.gov (United States)

    Nuermberger, Eric; Bishai, William R; Grosset, Jacques H

    2004-06-01

    Latent tuberculosis infection (LTBI) is a clinical condition characterized by a positive tuberculin skin test in the absence of clinical or radiological signs of active tuberculosis disease. It has been estimated that one third of the world's population is latently infected with Mycobacterium tuberculosis and serves as an enormous reservoir for future cases of active tuberculosis. The detection and treatment of individuals with LTBI and a high risk of progression to active tuberculosis are effective means to control the spread of tuberculosis. Furthermore, a better understanding of the host-pathogen interactions that result in latent infection could provide important insights for future drug or vaccine development. This chapter reviews recent developments in the molecular genetics, natural history, diagnosis, and treatment of LTBI within its historical context, including the impact of human immunodeficiency virus infection. Current treatment recommendations are also summarized.

  6. Potentiation of latent inhibition.

    Science.gov (United States)

    Rodriguez, Gabriel; Hall, Geoffrey

    2008-07-01

    Rats were given exposure either to an odor (almond) or a compound of odor plus taste (almond plus saline), prior to training in which the odor served as the conditioned stimulus. It was found, for both appetitive and aversive procedures, that conditioning was retarded by preexposure (a latent inhibition effect), and the extent of the retardation was greater in rats preexposed to the compound (i.e., latent inhibition to the odor was potentiated by the presence of the taste). In contrast, the presence of the taste during conditioning itself overshadowed learning about the odor. We argue that the presence of the salient taste in compound with the odor enhances the rate of associative learning, producing a rapid loss in the associability of the odor. This loss of associability will generate both overshadowing and the potentiation of latent inhibition that is observed after preexposure to the compound.

  7. A new light on caloric test--what was disclosed by three dimensional analysis of caloric nystagmus?

    Science.gov (United States)

    Arai, Y.

    2001-01-01

    For better understanding of caloric nystagmus, this phenomenon will be reviewed historically in three stages. 1) The first light on caloric nystagmus was thrown by Barany 1906. Through direct observation of eye movements, Barany established the caloric test as an important tool to determine the side of lesion for vertigo. 2) The second light is shed by electrooculogram (EOG) from the late 1950th. EOG enabled qualitative analysis of caloric nystagmus, and proved Barany's convection theory, but resulted in neglect of vertical and roll eye movements. 3) The third light is gained by 3D recording of eye movements started from the late 1980th. 3D recordings of eye movements enabled us to analyze the spatial orientation of caloric nystagmus, and disclose the close correlation of the nystagmus components in the head vertical and the space vertical planes, suggesting a contribution of the velocity storage integrator. The 3D property of caloric nystagmus will be explained in detail.

  8. Latent classification models

    DEFF Research Database (Denmark)

    Langseth, Helge; Nielsen, Thomas Dyhre

    2005-01-01

    One of the simplest, and yet most consistently well-performing setof classifiers is the \\NB models. These models rely on twoassumptions: $(i)$ All the attributes used to describe an instanceare conditionally independent given the class of that instance,and $(ii)$ all attributes follow a specific...... parametric family ofdistributions.  In this paper we propose a new set of models forclassification in continuous domains, termed latent classificationmodels. The latent classification model can roughly be seen ascombining the \\NB model with a mixture of factor analyzers,thereby relaxing the assumptions...... classification model, and wedemonstrate empirically that the accuracy of the proposed model issignificantly higher than the accuracy of other probabilisticclassifiers....

  9. Modeling microscale heat transfer using Calore.

    Energy Technology Data Exchange (ETDEWEB)

    Gallis, Michail A.; Rader, Daniel John; Wong, Chung-Nin Channy; Bainbridge, Bruce L.; Torczynski, John Robert; Piekos, Edward Stanley

    2005-09-01

    Modeling microscale heat transfer with the computational-heat-transfer code Calore is discussed. Microscale heat transfer problems differ from their macroscopic counterparts in that conductive heat transfer in both solid and gaseous materials may have important noncontinuum effects. In a solid material, three noncontinuum effects are considered: ballistic transport of phonons across a thin film, scattering of phonons from surface roughness at a gas-solid interface, and scattering of phonons from grain boundaries within the solid material. These processes are modeled for polycrystalline silicon, and the thermal-conductivity values predicted by these models are compared to experimental data. In a gaseous material, two noncontinuum effects are considered: ballistic transport of gas molecules across a thin gap and accommodation of gas molecules to solid conditions when reflecting from a solid surface. These processes are modeled for arbitrary gases by allowing the gas and solid temperatures across a gas-solid interface to differ: a finite heat transfer coefficient (contact conductance) is imposed at the gas-solid interface so that the temperature difference is proportional to the normal heat flux. In this approach, the behavior of gas in the bulk is not changed from behavior observed under macroscopic conditions. These models are implemented in Calore as user subroutines. The user subroutines reside within Sandia's Source Forge server, where they undergo version control and regression testing and are available to analysts needing these capabilities. A Calore simulation is presented that exercises these models for a heated microbeam separated from an ambient-temperature substrate by a thin gas-filled gap. Failure to use the noncontinuum heat transfer models for the solid and the gas causes the maximum temperature of the microbeam to be significantly underpredicted.

  10. A Dissociation between Recognition and Hedonic Value in Caloric and Non-caloric Carbonated Soft Drinks

    Directory of Open Access Journals (Sweden)

    Franco eDelogu

    2016-01-01

    Full Text Available Consumption of sugar-sweetened beverages (SSBs is considered to be a contributor to diabetes and the epidemic of obesity in many countries. The popularity of non-caloric carbonated soft drinks as an alternative to SSBs may be a factor in reducing the health risks associated with SSBs consumption. This study focuses on the perceptual discrimination of SSBs from artificially sweetened beverages (ASBs. 55 college students rated 14 commercially available carbonated soft drinks in terms of sweetness and likeability. They were also asked to recognize if the drinks contained sugar or a non-caloric artificial sweetener. Overall, participants showed poor accuracy in discriminating drinks’ sweeteners, with significantly lower accuracy for SSBs than ASBs. Interestingly, we found a dissociation between sweetener recognition and drink pleasantness. In fact, in spite of a chance-level discrimination accuracy of SSBs, their taste was systematically preferred to the taste of non-caloric beverages. Our findings support the idea that hedonic value of carbonated soft drinks is dissociable from its identification and that the activation of the pleasure system seems not to require explicit recognition of the sweetener contained in the soft drink. We hypothesize that preference for carbonated soft drinks containing sugar over non-caloric alternatives might be modulated by metabolic factors that are independent from conscious and rational consumers’ choices.

  11. A Dissociation Between Recognition and Hedonic Value in Caloric and Non-caloric Carbonated Soft Drinks

    Science.gov (United States)

    Delogu, Franco; Huddas, Claire; Steven, Katelyn; Hachem, Souheila; Lodhia, Luv; Fernandez, Ryan; Logerstedt, Macee

    2016-01-01

    Consumption of sugar-sweetened beverages (SSBs) is considered to be a contributor to diabetes and the epidemic of obesity in many countries. The popularity of non-caloric carbonated soft drinks as an alternative to SSBs may be a factor in reducing the health risks associated with SSBs consumption. This study focuses on the perceptual discrimination of SSBs from artificially sweetened beverages (ASBs). Fifty-five college students rated 14 commercially available carbonated soft drinks in terms of sweetness and likeability. They were also asked to recognize, if the drinks contained sugar or a non-caloric artificial sweetener. Overall, participants showed poor accuracy in discriminating drinks’ sweeteners, with significantly lower accuracy for SSBs than ASBs. Interestingly, we found a dissociation between sweetener recognition and drink pleasantness. In fact, in spite of a chance-level discrimination accuracy of SSBs, their taste was systematically preferred to the taste of non-caloric beverages. Our findings support the idea that hedonic value of carbonated soft drinks is dissociable from its identification and that the activation of the pleasure system seems not to require explicit recognition of the sweetener contained in the soft drink. We hypothesize that preference for carbonated soft drinks containing sugar over non-caloric alternatives might be modulated by metabolic factors that are independent from conscious and rational consumers’ choices. PMID:26858681

  12. A Dissociation Between Recognition and Hedonic Value in Caloric and Non-caloric Carbonated Soft Drinks.

    Science.gov (United States)

    Delogu, Franco; Huddas, Claire; Steven, Katelyn; Hachem, Souheila; Lodhia, Luv; Fernandez, Ryan; Logerstedt, Macee

    2016-01-01

    Consumption of sugar-sweetened beverages (SSBs) is considered to be a contributor to diabetes and the epidemic of obesity in many countries. The popularity of non-caloric carbonated soft drinks as an alternative to SSBs may be a factor in reducing the health risks associated with SSBs consumption. This study focuses on the perceptual discrimination of SSBs from artificially sweetened beverages (ASBs). Fifty-five college students rated 14 commercially available carbonated soft drinks in terms of sweetness and likeability. They were also asked to recognize, if the drinks contained sugar or a non-caloric artificial sweetener. Overall, participants showed poor accuracy in discriminating drinks' sweeteners, with significantly lower accuracy for SSBs than ASBs. Interestingly, we found a dissociation between sweetener recognition and drink pleasantness. In fact, in spite of a chance-level discrimination accuracy of SSBs, their taste was systematically preferred to the taste of non-caloric beverages. Our findings support the idea that hedonic value of carbonated soft drinks is dissociable from its identification and that the activation of the pleasure system seems not to require explicit recognition of the sweetener contained in the soft drink. We hypothesize that preference for carbonated soft drinks containing sugar over non-caloric alternatives might be modulated by metabolic factors that are independent from conscious and rational consumers' choices.

  13. Caloric versus low-caloric sweeteners: Can the body be fooled?

    NARCIS (Netherlands)

    Smeets, P.A.M.

    2010-01-01

    Low-caloric artificial sweeteners have been around for several decades now. Still, the debate over their usefulness in decreasing energy intake is ongoing. In principle, replacing sugar-containing foods with 'light' versions will lead to decreased energy intake. However, the reality of food intake b

  14. Balanço de energia em um solo cultivado com feijão caupi no brejo paraibano Energy balance in a soil cultivated with cowpeas in a mountaineous area in Paraiba, Brazil

    Directory of Open Access Journals (Sweden)

    José R. de S. Lima

    2005-12-01

    Full Text Available Os componentes do balanço de energia num solo cultivado com feijão caupi nas condições do Brejo Paraibano, foram determinados numa área de 4 ha do Centro de Ciências Agrárias, da UFPB, localizada no município de Areia, PB (6o 58' S, 35o 41' W e 620 m. Para tal, instalou-se uma torre no centro da área, contendo um pluviógrafo, um piranômetro, um saldo radiômetro e sensores para medida da temperatura e da umidade relativa do ar, em dois níveis acima do dossel da cultura; além disso, dois locais no solo foram instrumentados, cada um com duas sondas térmicas instaladas horizontalmente, nas profundidades de z1 = 2,0 cm e z2 = 8,0 cm, além de uma placa destinada à medida do fluxo de calor no solo, a 5,0 cm. Essas medidas foram armazenadas a cada 30 min, num sistema de aquisição de dados. Verificou-se que o valor médio do saldo de radiação (Rn foi de 78%, sendo a Rn utilizada, em média, como 71% no fluxo de calor latente (LE, 19% como fluxo de calor sensível (H e 10% como fluxo de calor no solo (G. A fração do saldo de radiação utilizada como fluxo de calor latente aumentou com a evolução da cobertura do solo pela cultura, enquanto a fração utilizada como fluxo de calor sensível e de calor no solo, diminuiu.The energy balance components in a cowpea crop growing in the mountain region of Paraiba, Brazil ("Brejo Paraibano" was determined in a 4 ha area in the Centro de Ciências Agrárias, UFPB, in the municipality of Areia, PB (6o 58' S, 35o 41' W e 620 m. Measurements of rainfall, net and global radiation were made. Sensors at two levels above the canopy were also mounted, allowing the measurements of air temperature and relative humidity. Below the soil surface, two different sites were provided with two thermal probes, horizontally installed at depths of 2.0 and 8.0 cm, besides a heat flux plate 5.0 cm deep for soil heat flux measurements. All data were stored in a datalogger each 30 min. The average value of the net

  15. Comparative analysis of the heat transfer rates in constant (CAV) and variable (VAV) volumes type multi zone acclimation system operating in hot and humid climate; Analise comparativa das taxas transferencia de calor em sistemas de climatizacao do tipo volume de ar constante (CAV) e volume de ar variavel (VAV) multizona operando em clima quente e umido

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Cesar A.G.; Correa, Jorge E. [Para Univ., Belem (Brazil). Centro Tecnologico. Dept. de Engenharia Mecanica]. E-mails: gsantos@ufpa.br; jecorrea@amazon.com.br

    2000-07-01

    This work performs a comparative analysis among the constant and variable air volume multi zones acclimation systems, used for provide the thermal comfort in buildings. The work used the simulation HVAC2KIT computer program. The results of sensible and latent heats transfer rates on the cooling and dehumidification, inflating fan capacity, and heat transfer on the final heating condenser were obtained and analysed for the climate conditions of the Brazilian city of Belem from Para State, presenting hot and humid climate during all the year.

  16. Dynamic Latent Classification Model

    DEFF Research Database (Denmark)

    Zhong, Shengtong; Martínez, Ana M.; Nielsen, Thomas Dyhre

    as possible. Motivated by this problem setting, we propose a generative model for dynamic classification in continuous domains. At each time point the model can be seen as combining a naive Bayes model with a mixture of factor analyzers (FA). The latent variables of the FA are used to capture the dynamics...... in the process as well as modeling dependences between attributes....

  17. New developments in caloric materials for cooling applications

    Directory of Open Access Journals (Sweden)

    S. Crossley

    2015-06-01

    Full Text Available Caloric materials are in the spotlight as candidates for future environmentally friendly cooling technologies. We describe stimulating recent developments in the three caloric strands that are now being studied collectively, namely magnetocaloric, electrocaloric and mechanocaloric (elastocaloric or barocaloric effects.

  18. A Dissociation between Recognition and Hedonic Value in Caloric and Non-caloric Carbonated Soft Drinks

    OpenAIRE

    Franco eDelogu; Claire eHuddas; Katelyn eSteven; Souheila eHachem; Luv eLodhia; Ryan eFernandez; Macee eLogerstedt

    2016-01-01

    Consumption of sugar-sweetened beverages (SSBs) is considered to be a contributor to diabetes and the epidemic of obesity in many countries. The popularity of non-caloric carbonated soft drinks as an alternative to SSBs may be a factor in reducing the health risks associated with SSBs consumption. This study focuses on the perceptual discrimination of SSBs from artificially sweetened beverages (ASBs). Fifty-five college students rated 14 commercially available carbonated soft drinks in terms ...

  19. Conservación por calor

    OpenAIRE

    Cobos García, Angel; Díaz Rubio, Olga

    2011-01-01

    Grao en Nutrición Humana e Dietética Esta unidade didáctica denominada Conservación por calor forma parte da materia «Tecnoloxía do procesado de alimentos» que se impartirá no primeiro semestre do 2º curso do Grao en Nutrición Humana e Dietética. A materia estrutúrase en diferentes unidades didácticas, tratando cada unha delas as diferentes tecnoloxías de procesado dos alimentos, tanto de conservación coma de transformación. A presente unidade didáctica aborda a conservación dos alimentos ...

  20. Caloric vestibular stimulation in aphasic syndrome

    Directory of Open Access Journals (Sweden)

    David eWilkinson

    2013-12-01

    Full Text Available Caloric vestibular stimulation (CVS is commonly used to diagnose brainstem disorder but its therapeutic application is much less established. Based on the finding that CVS increases blood flow to brain structures associated with language and communication, we assessed whether the procedure has potential to relieve symptoms of post-stroke aphasia. Three participants, each presenting with chronic, unilateral lesions to the left hemisphere, were administered daily CVS for 4 consecutive weeks. Relative to their pre-treatment baseline scores, two of the three participants showed significant improvement on both picture and responsive naming at immediate and one-week follow-up. One of these participants also showed improved sentence repetition, and another showed improved auditory word discrimination. No adverse reactions were reported. These data provide the first, albeit tentative, evidence that CVS may relieve expressive and receptive symptoms of aphasia. A larger, sham-controlled study is now needed to further assess efficacy.

  1. Produtividade de genótipos de batata inglesa tolerantes ao calor em duas épocas de plantio, no vale do São Francisco Productivity of heat tolerant potato genotypes in two planting times in São Francisco Valley, Northeast of Brazil

    Directory of Open Access Journals (Sweden)

    José Egídio Flori

    2000-07-01

    Full Text Available Com o objetivo de avaliar diferentes genótipos de batata tolerantes ao calor em duas épocas de plantio (inverno e primavera, instalaram-se dois experimentos no Campo Experimental de Bebedouro da Embrapa Semi-Árido, Petrolina (PE. O delineamento experimental foi blocos ao acaso com quatro repetições, utilizando-se os genótipos LT-9, 301251-1, 311320-1, 301217-1, 301159-1, Serrana x DTO-33 e a variedade comercial Baraka como testemunha. Na condição de clima quente (média de 25,8°C, o genótipo LT-9 apresentou a maior produtividade comercial (10,3 t/ha, seguido pelos demais tratamentos que não mostraram diferenças estatísticas entre si, à exceção de Serrana x DTO-33 que apresentou a menor produtividade (2,7 t/ha. O cultivo na condição de clima mais frio (média de 24,7°C, a produtividade total variou de 17,5 t/ha a 23,3 t/ha, sendo que o genótipo 301251-1 alcançou a maior produtividade (23,3 t/ha, não se verificando diferença estatística entre os tratamentos. Pelos resultados preliminares obtidos há indicação que os genótipos 301251-1, 311320-1; 301217-1 e 301159-1 podem ser plantados de abril a agosto como alternativas de cultivo à cultivar Baraka, necessitando, porém, de maiores investigações.The experiments were carried out at the Bebedouro Experimental Field of Embrapa Semi-Àrid Research Center in Petrolina, Brazil, to evaluate different heat tolerant potato genotypes under two climatic conditions. The experimental design was of randomized complete blocks with seven genotypes (LT-9, 301251-1, 311320-1, 301217-1, 301159-1, Serrana x DTO-33 and cv. Baraka and four replications. Under hot climatic condition (28°C the genotype LT-9 showed the highest commercial yield (10.3 t/ha, followed by the other treatments that didn't show statistical differences in relation to each other, except the genotype Serrana x DTO-33 which showed the lowest commercial yield (2.7 t/ha. Under favorable condition (23°C, the commercial

  2. Normal Caloric Responses during Acute Phase of Vestibular Neuritis

    Science.gov (United States)

    Lee, Sun-Uk; Park, Seong-Ho; Kim, Hyo-Jung; Koo, Ja-Won

    2016-01-01

    Background and Purpose We report a novel finding of caloric conversion from normal responses into unilateral paresis during the acute phase of vestibular neuritis (VN). Methods We recruited 893 patients with a diagnosis of VN at Dizziness Clinic of Seoul National University Bundang Hospital from 2003 to 2014 after excluding 28 patients with isolated inferior divisional VN (n=14) and those without follow-up tests despite normal caloric responses initially (n=14). We retrospectively analyzed the neurotological findings in four (0.5%) of the patients who showed a conversion from initially normal caloric responses into unilateral paresis during the acute phase. Results In those four patients, the initial caloric tests were performed within 2 days of symptom onset, and conversion into unilateral caloric paresis was documented 1–4 days later. The clinical and laboratory findings during the initial evaluation were consistent with VN in all four patients except for normal findings in bedside head impulse tests in one of them. Conclusions Normal findings in caloric tests should be interpreted with caution during the acute phase of suspected VN. Follow-up evaluation should be considered when the findings of the initial caloric test are normal, but VN remains the most plausible diagnosis. PMID:26932259

  3. Analysis of caloric test responses in sudden hearing loss.

    Science.gov (United States)

    Shih, Cheng-Ping; Chou, Yu-Ching; Chen, Hsin-Chien; Lee, Jih-Chin; Chu, Yueng-Hsiang; Wang, Chih-Hung

    2017-02-01

    Sudden sensorineural hearing loss is characterized by a rapid-onset hearing loss that develops within 3 days. Vertigo may also be present. We conducted a retrospective study to investigate whether the severity of a loss of caloric function is associated with the initial hearing loss and with hearing recovery. Our study population was made up of 135 patients-67 men and 68 women, aged 25 to 71 years (mean: 50.9)-with sudden sensorineural hearing loss who had undergone bithermal caloric testing. We compared various patient factors according to patients' hearing level and their response to caloric testing. We also analyzed the canal paresis (CP) value in patients with an abnormal caloric response according to three factors: disease severity, vertigo, and hearing recovery, and we evaluated the correlation between the loss of caloric function and hearing outcomes. We found that an abnormal caloric response was significantly associated with a profound hearing loss at presentation, the presence of vertigo, and poor hearing recovery. Among patients with an abnormal caloric response, the CP value was significantly correlated with hearing recovery (r = 0.503, p = 0.001). Poor hearing recovery was seen in 80% of patients with a CP value of ≥40% but in only 25% of patients with a value of hearing recovery was worse in the patients with a CP value of ≥40% (p = 0.002). We conclude that a CP value of ≥40% is a significant prognostic factor for an unfavorable treatment outcome.

  4. Otimização térmica e econômica de bomba de calor para aquecimento de água, utilizando programação quadrática sequencial e simulação através do método de substituição Newton Raphson

    OpenAIRE

    Obed Alexander Córdova Lobatón

    2011-01-01

    Resumo: O trabalho apresenta metodologias computacionais de otimização e simulação para o desenvolvimento do projeto de um sistema de bomba de calor para aquecimento de água em prédios residenciais, especialmente para uso em banho na região de Campinas. O sistema bomba de calor foi simulado focando o estudo nos trocadores de calor (evaporador e condensador). Cada componente foi otimizado mediante uma análise térmica e econômica que permitiu reduzir custos de investimento e de operação através...

  5. Peach latent mosaic viroid: not so latent.

    Science.gov (United States)

    Flores, Ricardo; Delgado, Sonia; Rodio, María-Elena; Ambrós, Silvia; Hernández, Carmen; Serio, Francesco D I

    2006-07-01

    SUMMARY Taxonomy: Peach latent mosaic viroid (PLMVd) is the type species of the genus Pelamoviroid within the family Avsunviroidae of chloroplastic viroids with hammerhead ribozymes. Physical properties: A small circular RNA of 336-351 nt (differences in size result from the absence or presence of certain insertions) adopting a branched conformation stabilized by a pseudoknot between two kissing loops. This particular conformation is most likely responsible for the insolubility of PLMVd in highly saline conditions (in which other viroids adopting a rod-like conformation are soluble). Both polarity strands are able to form hammerhead structures and to self-cleave during replication as predicted by these ribozymes. Biological properties: Although most infections occur without conspicuous symptoms, certain PLMVd isolates induce leaf mosaics, blotches and in the most extreme cases albinism (peach calico, PC), flower streaking, delays in foliation, flowering and ripening, deformations and decolorations of fruits, which usually present cracked sutures and enlarged roundish stones, bud necrosis, stem pitting and premature ageing of the trees, which also adopt a characteristic growing pattern (open habit). The molecular determinant for PC has been mapped at a 12-14-nt insertion that folds into a hairpin capped by a U-rich loop present only in certain variants. PLMVd is horizontally transmitted by the propagation of infected buds and to a lesser extent by pruning tools and aphids, but not by pollen; the viroid is not vertically transmitted through seed. Interesting features: This provides a suitable system for studying how a minimal non-protein-coding catalytic RNA replicates (subverting a DNA-dependent RNA polymerase to transcribe an RNA template), moves, interferes with the metabolism of its host (inciting specific symptoms and a defensive RNA silencing response) and evolves following a quasi-species model characterized by a complex spectrum of variants.

  6. Automobilismo: no calor da competição Automovilismo: en el calor de la competición Car racing: in the heat of competition

    Directory of Open Access Journals (Sweden)

    Luiz Oswaldo Carneiro Rodrigues

    2004-06-01

    Full Text Available O presente artigo questiona o papel do calor como um fator de risco adicional para o acidente que vitimou Ayrton Senna. O automobilismo de competição constitui um desafio biológico, uma situação estressante do ponto de vista mental e físico. A manutenção da performance depende da disponibilidade de carboidratos e oxigênio, hidratação adequada e temperatura interna constante entre 37 e 38 graus centígrados. A dissipação do calor produzido pelo metabolismo ocorre através do aumento do fluxo de sangue para pele e produção de suor e manter a temperatura cerebral constante se constitui num problema permanente. Verificou-se experimentalmente que a energia necessária para dirigir um automóvel de corrida é comparável a um esporte como o voleibol. Durante uma corrida, o indivíduo está exposto a um microambiente quente na cabina, que pode atingir 50ºC, gerado por fontes de calor mecânicas e ambientais. O bloqueio da evaporação do suor pelo macacão resulta em umidade e desconforto pessoal, o que implica maior esforço mental para dirigir o carro. As medidas contra o calor começam antes da corrida, cuidando-se do estado nutricional, da hidratação e principalmente do condicionamento físico através de exercícios aeróbios regulares e adequados, que permitem aumentar a capacidade de trabalho e a tolerância ao calor, o que resulta em menor fadiga durante a corrida. Outro procedimento importante deveria ser a aclimatação prévia dos pilotos aos ambientes quentes e úmidos. Deve-se fazer o possível para reduzir o aquecimento do veículo e respeitar o sistema de bandeiras de advertência para os riscos de hipertermia. Em conclusão, embora Ayrton Senna fosse um indivíduo com maior risco de desenvolver hipertermia, independentemente de outras causas, não parece ter havido tempo de corrida suficiente para haver produção de calor metabólico capaz de aumentar excessivamente a temperatura interna do piloto nas condi

  7. Latent inhibition in schizophrenia.

    Science.gov (United States)

    Swerdlow, N R; Braff, D L; Hartston, H; Perry, W; Geyer, M A

    1996-05-01

    Latent inhibition (LI) refers to the retarded acquisition of a conditioned response that occurs if the subject being tested is first preexposed to the to-be-conditioned stimulus (CS) without the paired unconditioned stimulus (UCS). Because the 'irrelevance' of the to-be-conditioned stimulus is established during non-contingent preexposure, the slowed acquisition of the CS-UCS association is thought to reflect the process of overcoming this learned irrelevance. Latent inhibition has been reported to be diminished in acutely hospitalized schizophrenia patients. If acutely hospitalized schizophrenia patients are preexposed to the CS, they learn the association as fast as, and perhaps faster than, patients who are not preexposed to the CS. This finding has been interpreted as reflecting the inability of acute schizophrenia patients to ignore irrelevant stimuli. In this study, the LI paradigm was identical to the one used in previous reports of LI deficits in schizophrenia patients (Baruch et al., 1988). Latent inhibition was observed in normal control subjects (n = 73), including individuals identified as 'psychosis-prone' based on established screening criteria, and in anxiety (n = 19) and mood disorder (n = 13) patients. Learning scores (trials to criterion) in "acutely' hospitalized as well as "chronic' hospitalized schizophrenia patients (n = 45) were significantly elevated in both preexposed and non-preexposed subjects, compared to controls. Acute schizophrenia patients exhibited intact LI. Separate cohorts of acute and chronic schizophrenia patients (n = 23) and normal controls (n = 34) exhibited intact LI when tested in a new, easier-to-acquire computerized LI paradigm. These results fail to identify specific LI deficits in schizophrenia patients, and raise the possibility that previously observed LI deficits in schizophrenia patients may reflect, at least in part, performance deficits related to learning acquisition.

  8. Characteristics of non caloric dulcorants and their use in children

    Directory of Open Access Journals (Sweden)

    Calzada León Raúl

    2014-07-01

    Full Text Available This is a descriptive review of the elaboration routes, the physical and chemical characteristics, metabolism and clearance, sweetener level, residual flavor, maximal recommended ingestion, security levels and the assessment of growth and development problems in children (from newborns, including prematures, to the end of puberty, of the main no caloric edulcorants used in Mexico. The no caloric edulcorants included in this review are: aspartame, acesulfame-K, sucralose, sacarin, ciclamates, thaumatin, D- tagatose, estevia and alitame.

  9. Um planejamento de experimentos para a avaliação do fluxo de calor crítico de reatores nucleares a água pressurizada de pequena escala.

    OpenAIRE

    2014-01-01

    Um dos parâmetros termo-hidráulicos de segurança mais importantes no projeto e operação de reatores a água pressurizada é o fluxo de calor crítico (FCC). O FCC ocorre quando se atinge uma região de instabilidade na mudança de mecanismo de transferência de calor de uma parede aquecida para um fluido, aumentado drasticamente a temperatura da parede. Transientes em um reator nuclear podem afetar a taxa de geração de calor ou a fluxo de refrigerante no núcleo, prejudicando a retirada de calor das...

  10. Changes of ampulla pressure in the semicircular canal of pigeons by caloric stimulation

    Science.gov (United States)

    Wada, Yoshiro; Suzuki, Hiroyuki; Watanabe, Satoru

    Still now several hypotheses about the mechanisms of the caloric nystagmus have been in conclusive. In this study we confirmed the convection effect and the volume change effect of the endolymph in horizontal semicircular canal following the caloric stimulation using pigeons ( Columba livia). Although the direction of the caloric nystagmus depended on the head position and the stimulus site of calorization, the caloric nystagmus disappeared after plugging of horizontal semicircular canal. On the other hand, the ampulla pressure increased by cold calorization and decreased by hot calorization and these pressure changes had no relation to the head position. These results show that the main role of the mechanisms of the caloric nystagmus under 1G is the convection effect but the volume change effect may act on the caloric nystagmus not only under 1G but also under microgravity.

  11. Modeling and design aspects of active caloric regenerators

    Science.gov (United States)

    Engelbrecht, Kurt

    2015-03-01

    A cooling device based on a solid caloric material using, for example, the elastocaloric, magnetocaloric, barocaloric or electrocaloric effect has the potential to replace vapor-compression based systems for a variety of applications. Any caloric device using a solid refrigerant may benefit from using a regenerative cycle to increase the operating temperature span. This presentation shows how all active caloric regenerators can be modeled using similar techniques and how they are related to passive regenerator performance. The advantages and disadvantages of using a regenerative cycle are also discussed. The issue of hysteresis in caloric materials is investigated from a system/thermodynamic standpoint and the effects on cooling power and efficiency are quantified using a numerical model of an active regenerator using model caloric materials with assumed properties. The implementation in a working device will be discussed for elastocaloric and magnetocaloric cooling devices. It is shown that demagnetization effects for magnetocaloric systems and stress concentration effects in elastocaloric system reduce the overall effect in the regenerator and care must be taken in regenerator design for both technologies. Other loss mechanisms outside the regenerator such as heat leaks are also discussed. Finally, experimental results for active magnetic regenerative cooler are given for a range of operating conditions. The most recently published device uses a regenerator consisting of Gd and three alloys of GdY and has demonstrated a COP over 3.

  12. Latent catalyst; Senzaisei shokubai

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    Epoxy resin, an important function material to support such main industries as electric and electronic devices, automobiles, civil engineering, and building construction, is demanded of development of single liquid type resin having excellent quick hardening performance and storage stability. This requirement comes from environmental problems with an intention of saving energies and reducing resin wastes. The Company, using freely its independent phase separation technology that controls molecular structure of catalysts, developed a latent catalyst having excellent storage stability and high-temperature quick hardening performance. Its major features may be summarized as follows: (1) excellent storage stability at room temperature keeping the product stable for 2.5 months or longer (2 days in conventional products); (2) quick hardening performance hardening the resin in seven seconds at 150 degrees C (equivalent to conventional products); and (3) excellent insulation performance of hardened resin at 140 degrees C of 7 times 10 {sup 13} (ohm) (center dot) cm (2 times 10 {sup 12} (ohm) (center dot) cm in conventional products) (translated by NEDO)

  13. Safety assessment and caloric value of partially hydrolyzed guar gum.

    Science.gov (United States)

    Finley, John W; Soto-Vaca, Adriana; Heimbach, James; Rao, T P; Juneja, Lekh Raj; Slavin, Joanne; Fahey, George C

    2013-02-27

    Guar gum and partially hydrolyzed guar gum (PHGG) are food ingredients that have been available for many years. PHGG is the partially hydrolyzed product from guar gum obtained from the Indian cluster bean (Cyanopsis tetragonolopus). The gum (CAS Registry No. 9000-30-0) is composed of galactomannan, a gel-forming polysaccharide with a molecular weight ranging from 200 to 300 kDa. The intact and partially hydrolyzed forms have multiple food applications. The intact material can be used to control the viscosity, stability, and texture of foods. PHGG is highly soluble and has little physical impact on foods. Both forms are indigestible but are excellent sources of fermentable dietary fiber. The caloric value of intact guar gum is accepted as 2.0, whereas the caloric value of PHGG has not been firmly established. It is the goal of this paper to review the chemistry, safety, in vivo effects, and caloric value of PHGG.

  14. [A caloric vestibular test with increased positive evidence (author's transl)].

    Science.gov (United States)

    Kurzeja, A; Strauss, P; Kapell, H

    1979-12-01

    A decrease of the variance of a caloric test would increase the importance of the statement of this test. An important source of variance are the differences concerning the timecourse of the induced heat wave, determined by the different anatomic conditions in the petrous bone, particularly the pneumatisation. A constant temperature gradient is obtained by the irigation in a pessimum position with the head flexed 30 degrees to the front. This temperature gradient evokes immediately a constant maximum vestibular stimulus after having reflected the head 90 degrees to the back. Comparing this new method with the traditional irrigation, one can state an important reduction of variance. The dependence of the nystagumus response on caloric irrigation of the petrous bone demands a X-ray-examination according to the technique of Schüller before starting with the caloric examination. In case of differences between the right and left sides the described test would be necessary in our opinion.

  15. Fast discriminative latent Dirichlet allocation

    Data.gov (United States)

    National Aeronautics and Space Administration — This is the code for fast discriminative latent Dirichlet allocation, which is an algorithm for topic modeling and text classification. The related paper is at...

  16. The Infinite Latent Events Model

    CERN Document Server

    Wingate, David; Roy, Daniel; Tenenbaum, Joshua

    2012-01-01

    We present the Infinite Latent Events Model, a nonparametric hierarchical Bayesian distribution over infinite dimensional Dynamic Bayesian Networks with binary state representations and noisy-OR-like transitions. The distribution can be used to learn structure in discrete timeseries data by simultaneously inferring a set of latent events, which events fired at each timestep, and how those events are causally linked. We illustrate the model on a sound factorization task, a network topology identification task, and a video game task.

  17. Estimativa do balanço de energia em cambarazal e pastagem no norte do Pantanal pelo método da razão de Bowen Estimate of energy balance in cambarazaland pasture in the north of Pantanal by Bowen ratio method

    Directory of Open Access Journals (Sweden)

    Marcelo Sacardi Biudes

    2009-06-01

    Full Text Available O estudo do balanço de energia de uma superfície vegetada e a atmosfera é importante para caracterizar o microclima local, identificar interações entre variáveis ambientais e a vegetação, e identificar efeitos das atividades antropogênicas. O objetivo deste trabalho foi estimar a variação sazonal do balanço de energia pelo método da razão de Bowen em uma área de vegetação monodominante de Cambará na RPPN SESC-Pantanal e uma área de pastagem na Fazenda Experimental da UFMT. Os componentes do balanço de energia apresentaram sazonalidade, com maiores médias na estação chuvosa nas duas áreas de estudo. No cambarazal houve maior variação do fluxo de calor latente da estação seca para a chuvosa que na pastagem. Entretanto, a variação sazonal do fluxo de calor sensível foi menor no cambarazal que na pastagem, devido ao efeito termo-regulador do cambarazal, em função da maior biomassa. A energia disponível aos dois sítios foi destinada prioritariamente em fluxo de calor latente, 80,0% no cambarazal e 56,6% na pastagem, seguido pelo fluxo de calor sensível, 19,1 e 42,9%, e pelo fluxo de calor no solo, 0,3 e 7,2%.The energy balance study of a vegetated surface and atmosphere is important to characterize the local microclimate, identify interactions among environmental variables and the vegetation and to identify anthropogenic activities effects. The objective of this work was estimate the seasonality of energy balance by Bowen ratio method in a monodominant vegetation of Cambará area in the RPPN SESC-Pantanal and a pasture area in UFMT's Experimental Farm. The energy balance components presented seasonality, with larger averages at the rainy station in two areas of study. In the cambarazal was a higher variation of the latent heat flux of the dry season for the rainy season that in the pasture. However, the seasonal variation of the sensible heat flux in the cambarazal was lower than in the pasture, due to the thermo

  18. Constrained caloric curves and phase transition for hot nuclei

    CERN Document Server

    Borderie, Bernard; Rivet, M F; Raduta, Ad R; Ademard, G; Bonnet, E; Bougault, R; Chbihi, A; Frankland, J D; Galichet, E; Gruyer, D; Guinet, D; Lautesse, P; Neindre, N Le; Lopez, O; Marini, P; Parlog, M; Pawlowski, P; Rosato, E; Roy, R; Vigilante, M

    2013-01-01

    Simulations based on experimental data obtained from multifragmenting quasi-fused nuclei produced in central $^{129}$Xe + $^{nat}$Sn collisions have been used to deduce event by event freeze-out properties in the thermal excitation energy range 4-12 AMeV [Nucl. Phys. A809 (2008) 111]. From these properties and the temperatures deduced from proton transverse momentum fluctuations, constrained caloric curves have been built. At constant average volumes caloric curves exhibit a monotonic behaviour whereas for constrained pressures a backbending is observed. Such results support the existence of a first order phase transition for hot nuclei.

  19. Distúrbios causados pelo frio e pelo calor durante corridas de longa distância

    Directory of Open Access Journals (Sweden)

    1999-06-01

    Full Text Available Muitos corredores amadores e de elite participam todos os anos de corridas de longa distância. Quando estes eventos ocorrem em temperaturas altas ou baixas, aumenta o risco de distúrbios térmicos. Contudo, a hipertermia induzida pelo exercício, a hipotermia, a desidratação e outros problemas relacionados podem ser minimizados através de esclarecimentos e um preparo antes do evento. Este documento fornece recomendações para o diretor médico e outras autoridades da organização das corridas nas seguintes áreas: planejamento, profissionais envolvidos na organização, instalações, suprimentos, equipamento e comunicação; fornecimento de esclarecimentos aos participantes; avaliação do estresse térmico; fornecimento de líquidos; e prevenção de questões legais em potencial. Este posicionamento oficial também descreve as condições predisponentes, as formas de diagnóstico e o tratamento dos quatro distúrbios ambientais mais comuns: exaustão pelo calor, colapso pelo calor, hipotermia e congelamento de extremidades. Os objetivos deste documento são: 1 Educar os organizadores e os participantes de corridas de longa distância a respeito das formas mais comuns de distúrbios térmicos incluindo as condições predisponentes, sinais de alerta, suscetibilidade e a redução de sua incidência; 2 Alertar os organizadores sobre as suas responsabilidades civis em potencial no que concerne à segurança do evento e à prevenção de lesões; 3 Recomendar que os organizadores consultem arquivos locais de meteorologia e planejem eventos em horas que provavelmente causem menos estresse térmico de modo a minimizar os efeitos deletérios sobre os participantes; 4 Estimular os organizadores a alertar os participantes sobre o estresse térmico no dia da corrida e as suas implicações no que tange aos distúrbios causados pelo frio e pelo calor; 5 Informar os organizadores sobre as ações preventivas que podem reduzir a incidência dos

  20. Apuntes de Transmisión del Calor

    OpenAIRE

    2013-01-01

    Esta publicacion está basada en unos apuntes para la parte de Transmisión del Calor de las asignaturas de la ETSAM. Sin embargo, con el tiempo se ha añadido otro material extra que excede ampliamente el contenido del curso.

  1. Influence of caloric intake on experimental carcinogenesis: a review.

    Science.gov (United States)

    Kritchevsky, D; Klurfeld, D M

    1986-01-01

    The effect of caloric intake on tumor growth has been recognized for over 70 years. Inhibition of tumor growth depends primarily on the extent of caloric restriction, but tumor type, animal strain, and dietary composition all exert some influence. Caloric restriction is most effective when maintained during both initiation and promotion, but if limited to one of these phases, restriction during promotion appears to be the more effective modality. The types of tumor that have been studied include spontaneous mammary and lung tumors as well as tumors induced by organ-specific carcinogens or irradiation with ultraviolet light. Numerous investigators have studied the effects of fat, and a diet low in calories but high in fat is generally significantly more effective in inhibiting carcinogenesis than is a diet high in calories but low in fat. Mice fed high fat, low calorie diets exhibited 48% fewer chemically induced skin tumors and 61% fewer tumors induced by ultraviolet irradiation than did mice fed low fat, high calorie diets. Mice fed a diet containing 2% fat exhibited a 66% incidence of skin tumors, whereas mice fed an isocaloric diet containing 61% fat showed a 78% incidence. Rats whose diet was restricted in calories by 40% exhibited no mammary tumors (coconut oil as primary dietary fat) or 75% fewer tumors (corn oil as dietary fat) compared to ad libitum-fed controls; they also exhibited 47% fewer colonic tumors. The mechanism by which caloric restriction exerts its tumor-inhibiting effects remains to be elucidated.

  2. Cupula dynamics under caloric stimulation of the semicircular canal

    Science.gov (United States)

    Kondrachuk, A. V.; Sirenko, S. P.

    Caloric stimulation of the semicircular canal SC is widely applied in studies of vestibular impairments Barany 1906 suggested that caloric response of SC results from mechanism of endolymph convection due to density changes of endolymph and therefore depends on the action of gravity forces However the Skylab experiments 1983 showed that the caloric reaction of SC can take place even under microgravity The studies of Scherer Clarke 1985 Harada Ariki 1985 Baumgarten et al 1985 considered the thermal expansion of endolymph to be a concurrent mechanism The model of caloric response based on the buoyancy force due to density change in the endolymph induced by thermal stimulation was proposed by Gentine et al 1990 1991 It should be noted that the first qualitative model that took into account the effect of endolymph thermal expansion under local heating to analyze the properties of primary afferents was proposed by Gusev Orlov 1977 However these models failed to answer the question which of the mentioned effects will be dominant under certain conditions The purpose of present study was to account for the expansion and convection of endolymph and to determine under which conditions one mechanism dominates over the other The consideration is based on the following model of SC Kondrachuk Sirenko 1990 an isolated torus filled by a compressible viscous Newton liquid endolymph the torus interior is plugged by an elastic body cupula the cupula surface in contact with endolymph is supposed to be stretched along the

  3. CALOR87: HETC87, MICAP, EGS4, and SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Gabriel, T.A.; Alsmiller, F.S.; Alsmiller, R.G. Jr.; Bishop, B.L.; Hermann, O.W.; Johnson, J.O.

    1987-01-01

    A brief history of CALOR (HETC, EGS, MICAP, SPECT) is presented to indicate the evolution of this code system. Details concerning the current modifications and additions to the high-energy transport code, HETC, are also presented and new comparisons with experimental data are included to verify the new physics improvements. 27 refs., 5 figs.

  4. Latent geometry of bipartite networks

    Science.gov (United States)

    Kitsak, Maksim; Papadopoulos, Fragkiskos; Krioukov, Dmitri

    2017-03-01

    Despite the abundance of bipartite networked systems, their organizing principles are less studied compared to unipartite networks. Bipartite networks are often analyzed after projecting them onto one of the two sets of nodes. As a result of the projection, nodes of the same set are linked together if they have at least one neighbor in common in the bipartite network. Even though these projections allow one to study bipartite networks using tools developed for unipartite networks, one-mode projections lead to significant loss of information and artificial inflation of the projected network with fully connected subgraphs. Here we pursue a different approach for analyzing bipartite systems that is based on the observation that such systems have a latent metric structure: network nodes are points in a latent metric space, while connections are more likely to form between nodes separated by shorter distances. This approach has been developed for unipartite networks, and relatively little is known about its applicability to bipartite systems. Here, we fully analyze a simple latent-geometric model of bipartite networks and show that this model explains the peculiar structural properties of many real bipartite systems, including the distributions of common neighbors and bipartite clustering. We also analyze the geometric information loss in one-mode projections in this model and propose an efficient method to infer the latent pairwise distances between nodes. Uncovering the latent geometry underlying real bipartite networks can find applications in diverse domains, ranging from constructing efficient recommender systems to understanding cell metabolism.

  5. The caloric vestibular nystagmus during short lasting microgravity

    Science.gov (United States)

    Oosterveld, W. J.; de Jong, H. A. A.; Kortschot, H. W.

    In human subjects the caloric vestibular test was conducted during parabolic flight. The ear irrigation was performed from 35 secs. till 5 secs. before the onset of microgravity. Nystagmography covered a 10-minutes period, including three parabolic manoeuvres of the aircraft. a. The slow phase velocity (SPV) of the caloric nystagmus increased proportionally with the value of the g-force. Introduction of microgravity induced an exponential decrease of the SPV decay. b. The nystagmus disappeared completely in microgravity, but SPV decay showed a specific time constant. c. The averaged time constant values of the caloric nystagmus SPV decay after sudden onset of microgravity and the averaged time constant of the SPV decay following a sudden stop after sustained rotation during 0-g appeared to be on the same level (10.2 s. and 10.6 s.). d. These two averaged time constant values obtained during shortlasting microgravity proved to be on a lower level than those time constants (15.5 secs.; 15.9 secs.) found in ground-based conditions. e. Because of the similarities in the characteristics of both SPV decay's and their accompanying time constants, a common working mechanism of cupular stimulation is likely. Most probably a fluid movement (or pressure) provokes a cupula deflexion followed by a cupula reflexion, either caused by a sudden stop after a sustained rotation or by a sudden onset of microgravity after g-load calorization. The present results support the Bárány convection theory with regard the endolymph stimulatory properties following the caloric test.

  6. Biomarkers of latent TB infection

    DEFF Research Database (Denmark)

    Ruhwald, Morten; Ravn, Pernille

    2009-01-01

    For the last 100 years, the tuberculin skin test (TST) has been the only diagnostic tool available for latent TB infection (LTBI) and no biomarker per se is available to diagnose the presence of LTBI. With the introduction of M. tuberculosis-specific IFN-gamma release assays (IGRAs), a new area...... of in vitro immunodiagnostic tests for LTBI based on biomarker readout has become a reality. In this review, we discuss existing evidence on the clinical usefulness of IGRAs and the indefinite number of potential new biomarkers that can be used to improve diagnosis of latent TB infection. We also present...... early data suggesting that the monocyte-derived chemokine inducible protein-10 may be useful as a novel biomarker for the immunodiagnosis of latent TB infection....

  7. Modeling Relational Data via Latent Factor Blockmodel

    CERN Document Server

    Gao, Sheng; Gallinari, Patrick

    2012-01-01

    In this paper we address the problem of modeling relational data, which appear in many applications such as social network analysis, recommender systems and bioinformatics. Previous studies either consider latent feature based models but disregarding local structure in the network, or focus exclusively on capturing local structure of objects based on latent blockmodels without coupling with latent characteristics of objects. To combine the benefits of the previous work, we propose a novel model that can simultaneously incorporate the effect of latent features and covariates if any, as well as the effect of latent structure that may exist in the data. To achieve this, we model the relation graph as a function of both latent feature factors and latent cluster memberships of objects to collectively discover globally predictive intrinsic properties of objects and capture latent block structure in the network to improve prediction performance. We also develop an optimization transfer algorithm based on the general...

  8. Infecção tuberculosa latente em profissionais contatos e não contatos de detentos de duas penitenciárias do estado de São Paulo, Brasil, 2008 Latent tuberculosis among professionals with and without direct contact with inmates of two penitentiaries in the state of São Paulo, Brazil, 2008

    Directory of Open Access Journals (Sweden)

    Péricles Alves Nogueira

    2011-09-01

    Full Text Available INTRODUÇÃO: Para grupos de pessoas que permanecem confinadas, principalmente em presídios, a tuberculose sempre foi um grave problema de saúde, devido a sua transmissão respiratória, colocando em risco os profissionais que trabalham no sistema prisional, especialmente os contatos de detentos. OBJETIVO: Conhecer a prevalência de infecção pelo Mycobacterium tuberculosis entre os profissionais contatos e não contatos de detentos de duas penitenciárias do Estado de São Paulo. MÉTODOS: Este estudo consistiu na aplicação de um questionário individual; aplicação e leitura da prova tuberculínica; baciloscopia e cultura dos escarros, com posterior identificação e teste de sensibilidade às drogas antituberculose das cepas isoladas, no período de março a junho de 2008. RESULTADOS: Foram examinados 277 (48,3% profissionais dos 574 existentes. Foram aplicados e lidos 248 (89,5% testes tuberculínicos (PPD-RT23 - 2TU/0,1 mL, sendo que 194 foram em profissionais que trabalhavam diretamente com os detentos, ou seja, eram contatos e 54, em não contatos. Entre os contatos, 62,4% apresentaram enduração maior que 10 mm e entre os não contatos, 38,9% foram reatores ao teste tuberculínico. Não houve exame de escarro positivo na baciloscopia e na cultura, ou seja, não foi identificado nenhum caso de tuberculose doença entre os profissionais, no momento da pesquisa. CONCLUSÃO: Este estudo sugere que os profissionais que têm contato direto com os detentos, têm um risco maior de se infectar pelo M. tuberculosis e adoecer por tuberculose.INTRODUCTION: For groups of persons who remain confined, mainly in prisons, tuberculosis has always been a serious health problem, due to its transmission respiratory, putting in risk the professionals that work in a prison, especially the communicants of inmates. OBJECTIVE: To know the infection prevalence for the Mycobacterium tuberculosis among the employees communicating and no communicating of

  9. DESARROLLOS INSTRUMENTALES EN MICROCALORIMETRIA DE CONDUCCIÓN DE CALOR

    Directory of Open Access Journals (Sweden)

    Liliana Giraldo G.

    2010-09-01

    Full Text Available Se presentan aspectos generales de la microcalorimetría de conducción de calor. Se describe el diseño y la operación de microcalorímetros de conducción de calor estático y de flujo construidos en este laboratorio, los cuales fueron calibrados eléctrica y químicamente. Estos equipos se emplean en la caracterización de sólidos porosos por la técnica de calorimetría de inmersión y en la determinación de entalpias de transferencia de solutos; su uso se ilustra con algunos resultados típicos. Se mencionan además otras aplicaciones que se dan actualmente a estos aparatos.

  10. Caloric values for young sprouts of nine hardwood species

    Energy Technology Data Exchange (ETDEWEB)

    Neenan, M. (An Foras Taluntais, Oak Park, Carlow, Ireland); Steinbeck, K.

    1979-09-01

    Caloric content, specific gravity, and ash content of 6- to 15-year-old sprouts of nine hardwood species were determined in midsummer. Energy values for wood, bark, first order branches, twigs, and leaves were determined with an adiabatic bomb calorimeter. The values found for coppice material averaged 4791 cal/g and were comparable to published values for older wood. Intraspecific differences among tissues were greater than the relatively small but significant differences among species. Differences in yield potential are therefore likely to outweigh variations in caloric content among species where total energy production per unit of land area is concerned. Ash content varied from 0.65 percent for wood to 5.88 percent for bark.

  11. Analysis of latent structures in linear systems

    DEFF Research Database (Denmark)

    Høskuldsson, Agnar

    2004-01-01

    In chemometrics the emphasis is on latent structure models. The latent structure is the part of the data that the modeling task is based upon. This paper is addressing some fundamental issues, when latent structures are used. The paper consists of three parts. The first part is concerned defining...

  12. A Multicomponent Latent Trait Model for Diagnosis

    Science.gov (United States)

    Embretson, Susan E.; Yang, Xiangdong

    2013-01-01

    This paper presents a noncompensatory latent trait model, the multicomponent latent trait model for diagnosis (MLTM-D), for cognitive diagnosis. In MLTM-D, a hierarchical relationship between components and attributes is specified to be applicable to permit diagnosis at two levels. MLTM-D is a generalization of the multicomponent latent trait…

  13. Caloric Effects in Methylammonium Lead Iodide from Molecular Dynamics Simulations

    OpenAIRE

    Liu, Shi; Cohen, Ronald E.

    2016-01-01

    Organic-inorganic hybrid perovskite architecture could serve as a robust platform for materials design to realize functionalities beyond photovoltaic applications. We explore caloric effects in organometal halide perovskites, taking methylammonium lead iodide (MAPbI$_3$) as an example, using all-atom molecular dynamics simulations with a first-principles based interatomic potential. The adiabatic thermal change is estimated directly by introducing different driving fields in the simulations. ...

  14. Latent geometry of bipartite networks

    CERN Document Server

    Kitsak, Maksim; Krioukov, Dmitri

    2016-01-01

    Despite the abundance of bipartite networked systems, their organizing principles are less studied, compared to unipartite networks. Bipartite networks are often analyzed after projecting them onto one of the two sets of nodes. As a result of the projection, nodes of the same set are linked together if they have at least one neighbor in common in the bipartite network. Even though these projections allow one to study bipartite networks using tools developed for unipartite networks, one-mode projections lead to significant loss of information and artificial inflation of the projected network with fully connected subgraphs. Here we pursue a different approach for analyzing bipartite systems that is based on the observation that such systems have a latent metric structure: network nodes are points in a latent metric space, while connections are more likely to form between nodes separated by shorter distances. This approach has been developed for unipartite networks, and relatively little is known about its appli...

  15. Advancement of Latent Trait Theory.

    Science.gov (United States)

    1988-02-01

    Estimation with the Multiple-Choice Test Item. American Educational Research Association Meeting, New Orleans, 1984. (Coauthorship with Paul S. Changas...Chicago, 1985. U. S. A. (Coauthorship with Paul S. Changas) (10) Expansion of the General Model for the Homogeneous Case of the Continuous Response Level...17-20. [2] Lazarsfeld , P. F. Latent structure analysis. In S. Koch (Ed.), Psychology: a study of a science, Volume 3. McGraw-Hill, 1959, pages 476-542

  16. Latent heat of vehicular motion

    Science.gov (United States)

    Ahmadi, Farzad; Berrier, Austin; Habibi, Mohammad; Boreyko, Jonathan

    2016-11-01

    We have used the thermodynamic concept of latent heat, where a system loses energy due to a solid-to-liquid phase transition, to study the flow of a group of vehicles moving from rest. During traffic flow, drivers keep a large distance from the car in front of them to ensure safe driving. When a group of cars comes to a stop, for example at a red light, drivers voluntarily induce a "phase transition" from this "liquid phase" to a close-packed "solid phase." This phase transition is motivated by the intuition that maximizing displacement before stopping will minimize the overall travel time. To test the effects of latent heat on flow efficiency, a drone captured the dynamics of cars flowing through an intersection on a Smart Road where the initial spacing between cars at the red light was systematically varied. By correlating the experimental results with the Optimal Velocity Model (OVM), we find that the convention of inducing phase transitions at intersections offers no benefit, as the lag time (latent heat) of resumed flow offsets the initial increase in displacement. These findings suggest that in situations where gridlock is not an issue, drivers should not decrease their spacing during stoppages in order to maximize safety with no loss in flow efficiency.

  17. The Lexicocalorimeter: Gauging public health through caloric input and output on social media

    CERN Document Server

    Alajajian, S E; Reagan, A J; Alajajian, S C; Frank, M R; Mitchell, L; Lahne, J; Danforth, C M; Dodds, P S

    2015-01-01

    We propose and develop a Lexicocalorimeter: an online, interactive instrument for measuring the "caloric content" of social media and other large-scale texts. We do so by constructing extensive yet improvable tables of food and activity related phrases, and respectively assigning them with sourced estimates of caloric intake and expenditure. We show that for Twitter, our naive measures of "caloric input", "caloric output", and the ratio of these measures---"caloric balance"---are all strong correlates with health and well-being demographics for the contiguous United States. Our caloric balance measure outperforms both its constituent quantities, is tunable to specific demographic measures such as diabetes rates, provides a real-time signal reflecting a population's health, and has the potential to be used alongside traditional survey data in the development of public policy and collective self-awareness. Because our Lexicocalorimeter is a linear superposition of principled phrase scores, we also show we can m...

  18. Seleção de linhagens com tolerância ao calor em germoplasma de tomateiro coletado na região Norte do Brasil Selection of heat tolerant tomato inbred lines from landraces adapted for cultivation in the North Region of Brazil

    Directory of Open Access Journals (Sweden)

    Leonardo de B. Giordano

    2005-03-01

    Full Text Available As altas temperaturas nas regiões tropicais e equatoriais induzem uma série de distúrbios morfológicos e/ou fisiológicos em estruturas florais do tomateiro, resultando em menor produtividade devido a maiores taxas de abortamento e má formação de frutos. Neste trabalho foram avaliadas linhagens de tomateiro oriundas de duas populações que vêm sendo cultivadas em Roraima, região Norte do Brasil. Doze linhagens foram obtidas após um ciclo prévio de seleção (em Brasília-DF em condições de temperatura elevada. A avaliação destas doze linhagens e duas cultivares testemunhas ('Viradoro' e 'Santa Clara' foi conduzida em casa de vegetação com temperaturas média das mínimas de 15ºC e média das máximas de 46,2ºC. Foram observadas diferenças significativas para número de frutos abortados, número de frutos maduros, peso de frutos maduros, teores de sólidos solúveis, firmeza e coloração de frutos. As linhagens (como um grupo apresentaram melhor desempenho do que as testemunhas 'Viradoro' e 'Santa Clara' para os parâmetros número de frutos abortados, peso, número e coloração de frutos maduros. A metodologia adotada no presente trabalho, permite a identificação de genótipos superiores adaptados ao cultivo em regiões tropicais e equatoriais com elevadas temperaturas.Heat tolerance is a major trait for tomato breeding programs targeted for lowland wet climates in equatorial and tropical areas of the world. High temperatures might cause several disturbances to morphological and physiological characteristics of the tomato flowers leading to yield constraints due to reduction in fruit setting. In the present work, an experiment was conducted to evaluate tomato breeding lines, derived from two tomato landrace populations cultivated by farmers in Roraima State (North Region of Brazil. Twelve inbred lines were obtained from these populations after one cycle of selection in a plastic house with high temperatures. These 12

  19. Respostas pós-colheita de abacaxi 'Pérola' no tratamento com calor e armazenagem refrigerada

    Directory of Open Access Journals (Sweden)

    Rosilene Ferreira Souto

    2014-12-01

    Full Text Available Este trabalho teve como objetivo avaliar o efeito de diferentes temperaturas de armazenamento e do tratamento inicial a 40 ºC, por 24 horas, na preservação de abacaxis 'Pérola'. Os abacaxis foram colhidos no estádio de maturação "pintado", tratados com calor e foram mantidos sob condição de ambiente (25 ºC e 75-80% UR ou refrigerados durante 17 dias, a 8 ºC, ou 14 ºC. Após este período, foram transferidos para condição de ambiente, 25 ºC e 75-80% UR. As avaliações foram realizadas no início (0 dia e após 1; 5; 9; 13 ou 17 dias. Os frutos armazenados sob refrigeração foram transferidos para o ambiente e também foram avaliados aos 21, 25 ou 29 dias. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema fatorial (2x3x9, tendo-se os fatores, frutos tratados com calor ou não, três temperaturas de armazenamento e 9 épocas de avaliação. Os frutos foram avaliados quanto à perda de massa fresca, coloração externa, resistência da casca e da polpa, rendimento em polpa, além da intensidade respiratória. A perda de massa fresca e a resistência da casca e da polpa foram maiores nos frutos armazenados sob condição ambiente quando comparada à perda de massa e resistência dos abacaxis armazenados sob refrigeração, com variação na coloração da casca, de verde para amarela, com a evolução do tempo. Os abacaxis mantidos sob refrigeração a 8 ºC ou 14 ºC tiveram vida útil de 29 dias, enquanto os abacaxis mantidos a 25 ºC foram descartados após 17 dias. Abacaxis tratados com calor apresentaram a maior taxa respiratória, enquanto aqueles mantidos a 8 ºC apresentaram a menor atividade respiratória, tanto sob refrigeração como em condição ambiente.

  20. La isla de calor estival en Temuco, Chile

    Directory of Open Access Journals (Sweden)

    Alicia Capelli de Steffens

    2001-01-01

    Full Text Available Temuco es una ciudad localizada en el centro sur de Chile (38º 45’ S y 72º 40’ W. Morfológicamente, el sitio de la ciudad corresponde a las terrazas fluviales del río Cautín que se desarrollan en forma encajonada entre los cerros Ñielol (350 m y Conunhueno (360 m. Esta ciudad se ha desarrollado rápidamente en las últimas décadas, por lo tanto es necesario conocer el efecto antrópico en la misma. Para evaluar parte de ese efecto se analiza la isla de calor urbana estival en la ciudad de Temuco, Chile. Se efectuaron mediciones de temperatura del aire y humedad a través de la ciudad para determinar la forma y la intensidad de la isla de calor urbano. Se utilizaron estaciones móviles e información de una estación meteorológica fija. La ciudad presenta un comportamiento térmico diferente a lo largo del día. Durante el día genera una isla de calor que responde en líneas generales al modelo ideal de calentamiento urbano. La intensidad de la isla calórica (∆Tu-r fue 6.3ºC y 1.2ºC durante el día y la noche, respectivamente. La influencia de los cerros que limitan la ciudad es importante. El estudio confirma la idea que el clima urbano de una ciudad es un mosaico de microclimas que interactuan continuamente.

  1. A crise do socialismo analisada no calor da hora

    Directory of Open Access Journals (Sweden)

    Reginaldo Benedito Dias

    2009-11-01

    Full Text Available O presente artigo demonstra como os acontecimentos que levaram à crise e desintegração dos países do bloco soviético foram analisados no calor dos acontecimentos, tomando como parâmetro os livros "Nós, o povo" e "A desintegração do monolito", selecionados por causa das diferentes perspectivas metodológicas e ideológicas que representam.  

  2. Latent herpesvirus infection arms NK cells.

    Science.gov (United States)

    White, Douglas W; Keppel, Catherine R; Schneider, Stephanie E; Reese, Tiffany A; Coder, James; Payton, Jacqueline E; Ley, Timothy J; Virgin, Herbert W; Fehniger, Todd A

    2010-06-03

    Natural killer (NK) cells were identified by their ability to kill target cells without previous sensitization. However, without an antecedent "arming" event, NK cells can recognize, but are not equipped to kill, target cells. How NK cells become armed in vivo in healthy hosts is unclear. Because latent herpesviruses are highly prevalent and alter multiple aspects of host immunity, we hypothesized that latent herpesvirus infection would arm NK cells. Here we show that NK cells from mice latently infected with Murid herpesvirus 4 (MuHV-4) were armed as evidenced by increased granzyme B protein expression, cytotoxicity, and interferon-gamma production. NK-cell arming occurred rapidly in the latently infected host and did not require acute viral infection. Furthermore, NK cells armed by latent infection protected the host against a lethal lymphoma challenge. Thus, the immune environment created by latent herpesvirus infection provides a mechanism whereby host NK-cell function is enhanced in vivo.

  3. Latent semantics as cognitive components

    DEFF Research Database (Denmark)

    Petersen, Michael Kai; Mørup, Morten; Hansen, Lars Kai

    2010-01-01

    Cognitive component analysis, defined as an unsupervised learning of features resembling human comprehension, suggests that the sensory structures we perceive might often be modeled by reducing dimensionality and treating objects in space and time as linear mixtures incorporating sparsity...... emotional responses can be encoded in words, we propose a simplified cognitive approach to model how we perceive media. Representing song lyrics in a vector space of reduced dimensionality using LSA, we combine bottom-up defined term distances with affective adjectives, that top-down constrain the latent......, which we suggest might function as cognitive components for perceiving the underlying structure in lyrics....

  4. Latent methane in fossil coals

    Energy Technology Data Exchange (ETDEWEB)

    A.D. Alexeev; E.V. Ulyanova; G.P. Starikov; N.N. Kovriga [Academy of Sciences of Ukraine, Donetsk (Ukraine). Institute for Physics of Mining Processes

    2004-07-01

    It is established experimentally using 1H NMR wide line spectroscopy that methane can exist in coals not only in open or closed porosity and fracture systems but also in solid solutions in coal substance, in particular, under methane pressure 2 MPa or higher. Methane dissolved in coal minerals reversibly modifies their lattice parameters as determined from X-ray diffraction analysis. Co-existence of these methane forms in fossil coals causes multi-step desorption kinetics. It is shown experimentally that the long-term latent methane desorption is effected mainly by closed porosity, which in turn is determined by coal rank. 21 refs., 3 figs., 2 tabs.

  5. Enhanced latent inhibition in high schizotypy individuals

    OpenAIRE

    Granger, Kiri T.; Moran, Paula M.; Buckley, Matthew G.; Haselgrove, Mark

    2016-01-01

    Latent inhibition refers to a retardation in learning about a stimulus that has been rendered familiar by non-reinforced preexposure, relative to a non-preexposed stimulus. Latent inhibition has been shown to be inversely correlated with schizotypy, and abnormal in people with schizophrenia, but these findings are inconsistent. One potential contributing factor to this inconsistency is that many tasks that purport to measure latent inhibition are confounded by alternative effects that also re...

  6. Bayesian variable selection for latent class models.

    Science.gov (United States)

    Ghosh, Joyee; Herring, Amy H; Siega-Riz, Anna Maria

    2011-09-01

    In this article, we develop a latent class model with class probabilities that depend on subject-specific covariates. One of our major goals is to identify important predictors of latent classes. We consider methodology that allows estimation of latent classes while allowing for variable selection uncertainty. We propose a Bayesian variable selection approach and implement a stochastic search Gibbs sampler for posterior computation to obtain model-averaged estimates of quantities of interest such as marginal inclusion probabilities of predictors. Our methods are illustrated through simulation studies and application to data on weight gain during pregnancy, where it is of interest to identify important predictors of latent weight gain classes.

  7. Isla de calor en Toluca, México

    Directory of Open Access Journals (Sweden)

    Carlos Constantino Morales Méndez

    2007-01-01

    Full Text Available El clima de la ciudad de Toluca y del mundo ha sido modificado como consecuencia del crecimiento de su población y el aumento de las dimensiones de su distribución territorial. Las variaciones atmosféricas son más acusadas entre los espacios urbanos y rurales a medida que las ciudades son más grandes y su mancha urbana es más extensa,así como de la reducción de la vegetación, el aumento en la calefacción en casas y edificios y por la contaminación del aire. Para identificar los espacios con calor más intenso por la infraestructura urbana, se propone una metodología que consiste en la determinación de los valores de temperatura que se registraron en dos días típicos de invierno y verano, durante el día y la noche,mostrando la distribución de la isla de calor en la zona de estudio, a partir de los datos delas estaciones de la Red Automática de Monitoreo Ambiental (RAMA. Asimismo, se considera el comportamiento y variación de algunas variables atmosféricas como humedad relativa, precipitación y viento, para mostrar su comportamiento relativamente anómalo en la zona urbana.

  8. Lifelong caloric restriction increases working memory in mice.

    Directory of Open Access Journals (Sweden)

    Angela Kuhla

    Full Text Available Caloric restriction (CR is argued to positively affect general health, longevity and the normally occurring age-related reduction of cognition. This issue is well examined, but most studies investigated the effect of short-term periods of CR. Herein, 4 weeks old female mice were fed caloric restricted for 4, 20 and especially for 74 weeks. CR mice received 60% of food eaten by their ad libitum (AL fed littermates, and all age-matched groups were behaviorally analyzed. The motor coordination, which was tested by rotarod/accelerod, decreased age-related, but was not influenced by the different periods of CR. In contrast, the age-related impairment of spontaneous locomotor activity and anxiety, both being evaluated by open field and by elevated plus maze test, was found aggravated by a lifelong CR. Measurement of cognitive performance with morris water maze showed that the working memory decreased age-related in AL mice, while a lifelong CR caused a better cognitive performance and resulted in a significantly better spatial memory upon 74 weeks CR feeding. However, a late-onset CR feeding in 66 weeks old mice did not ameliorate the working memory. Therefore, a lifelong CR seems to be necessary to improve working memory.

  9. Lifelong caloric restriction increases working memory in mice.

    Science.gov (United States)

    Kuhla, Angela; Lange, Sophie; Holzmann, Carsten; Maass, Fabian; Petersen, Jana; Vollmar, Brigitte; Wree, Andreas

    2013-01-01

    Caloric restriction (CR) is argued to positively affect general health, longevity and the normally occurring age-related reduction of cognition. This issue is well examined, but most studies investigated the effect of short-term periods of CR. Herein, 4 weeks old female mice were fed caloric restricted for 4, 20 and especially for 74 weeks. CR mice received 60% of food eaten by their ad libitum (AL) fed littermates, and all age-matched groups were behaviorally analyzed. The motor coordination, which was tested by rotarod/accelerod, decreased age-related, but was not influenced by the different periods of CR. In contrast, the age-related impairment of spontaneous locomotor activity and anxiety, both being evaluated by open field and by elevated plus maze test, was found aggravated by a lifelong CR. Measurement of cognitive performance with morris water maze showed that the working memory decreased age-related in AL mice, while a lifelong CR caused a better cognitive performance and resulted in a significantly better spatial memory upon 74 weeks CR feeding. However, a late-onset CR feeding in 66 weeks old mice did not ameliorate the working memory. Therefore, a lifelong CR seems to be necessary to improve working memory.

  10. High monetary reward rates and caloric rewards decrease temporal persistence

    Science.gov (United States)

    Bode, Stefan; Murawski, Carsten

    2017-01-01

    Temporal persistence refers to an individual's capacity to wait for future rewards, while forgoing possible alternatives. This requires a trade-off between the potential value of delayed rewards and opportunity costs, and is relevant to many real-world decisions, such as dieting. Theoretical models have previously suggested that high monetary reward rates, or positive energy balance, may result in decreased temporal persistence. In our study, 50 fasted participants engaged in a temporal persistence task, incentivised with monetary rewards. In alternating blocks of this task, rewards were delivered at delays drawn randomly from distributions with either a lower or higher maximum reward rate. During some blocks participants received either a caloric drink or water. We used survival analysis to estimate participants' probability of quitting conditional on the delay distribution and the consumed liquid. Participants had a higher probability of quitting in blocks with the higher reward rate. Furthermore, participants who consumed the caloric drink had a higher probability of quitting than those who consumed water. Our results support the predictions from the theoretical models, and importantly, suggest that both higher monetary reward rates and physiologically relevant rewards can decrease temporal persistence, which is a crucial determinant for survival in many species. PMID:28228517

  11. IDENTIFICAÇÃO DE ILHAS DE CALOR POR MEIO DE SENSORIAMENTO REMOTO: ESTUDO DE CASO NO MUNICÍPIO DE GOIÂNIA – GO/2001

    Directory of Open Access Journals (Sweden)

    Diego Tarley Ferreira Nascimento

    2009-06-01

    Full Text Available No presente trabalho são utilizadas técnicas de sensoriamento remoto para identificação e análise do fenômeno de ilhas de calor em Goiânia-GO, tendo como recorte temporal o ano de 2001. Foi utilizada a proposta metodológica de Monteiro (1976, do Sistema de Clima Urbano – SCU, em particular o subsistema Termodinâmico, visando proceder a uma análise do funcionamento, desempenho e organização do fenômeno de ilhas de calor. A elaboração do trabalho baseou-se na classificação da cobertura do solo e em um mapeamento do campo térmico do município de Goiânia, por meio das imagens das bandas 3, 4, 5 e 6 (banda termal do Landsat 7, nas quais foram considerados como instrumentos de análise: a urbanização, as características geoecológicas (topografia e o sistema meteorológico (clima regional. Os resultados demonstram que o fenômeno de ilha de calor é constatado no município de Goiânia, havendo diferenças de temperatura de até 10°C entre a área urbana e a rural do município, sendo possível caracterizar determinados usos antrópicos (classes de cobertura do solo e intervalos altimétricos como potencializadores de maiores valores de temperatura.

  12. Estimulação calórica gelada com ar nas vestibulopatias periféricas crônicas com nistagmo espontâneo Ice air caloric test in chronic peripheral vestibular dysfunction with spontaneous nystagmus

    Directory of Open Access Journals (Sweden)

    Flavia Silveira dos Santos Cabral

    2008-01-01

    Full Text Available OBJETIVO: analisar o efeito da estimulação gelada com ar a 10ºC sobre o nistagmo pós-calórico em pacientes com vestibulopatias periféricas crônicas que apresentam nistagmo espontâneo com olhos fechados. MÉTODOS: 61 pacientes foram submetidos às estimulações com ar a 42, 18 e 10ºC. RESULTADOS: em 42 casos (69,8% foram encontrados valores anormais de preponderância direcional e/ou de predomínio labiríntico a 42 e 18ºC. A prova a 10ºC apresentou valores de assimetria dentro dos padrões de normalidade em 52,5% dos casos e valores anormais de assimetria em 16,4% (p=0,012, confirmou hiporreflexia unilateral em 11,5% e identificou anormalidades não evidenciadas a 42 e 18ºC em 8,2%. CONCLUSÃO: a estimulação gelada com ar a 10ºC possibilitou retirar a influência do nistagmo espontâneo de olhos fechados sobre o nistagmo pós-calórico em pacientes com vestibulopatias periféricas crônicas.PURPOSE: to analyze the effect of air caloric stimulation at 10ºC on the post-caloric responses in patients with chronic peripheral dysfunction who presented spontaneous nystagmus with the eyes closed. METHODS: 61 patients with spontaneous nystagmus with closed eyes were submitted to air caloric stimulation under the following temperatures: 42, 18 and 10ºC. RESULTS: in 42 patients (69.8%, abnormal values of directional preponderance and / or unilateral hypoexcitability were observed following the 42ºC and 18ºC stimulations. For the 10ºC stimulations an asymmetry within normal limits was seen in 52.5% of the patients, while abnormal values were seen in 16.4% (p=0.012. Unilateral hypoexcitability was confirmed in 11.5% of the cases. In 8.2% of the patients there were abnormal findings not evidenced under 42ºC and 18ºC stimulations. CONCLUSION: in patients with chronic peripheral labyrinthine disorders who show spontaneous nystagmus with closed eyes, the 10ºC caloric test makes it possible to remove the influence of the spontaneous

  13. Learning Latent Structure in Complex Networks

    DEFF Research Database (Denmark)

    Mørup, Morten; Hansen, Lars Kai

    such as the Modularity, it has recently been shown that latent structure in complex networks is learnable by Bayesian generative link distribution models (Airoldi et al., 2008, Hofman and Wiggins, 2008). In this paper we propose a new generative model that allows representation of latent community structure...

  14. Introduction to Latent Class Analysis with Applications

    Science.gov (United States)

    Porcu, Mariano; Giambona, Francesca

    2017-01-01

    Latent class analysis (LCA) is a statistical method used to group individuals (cases, units) into classes (categories) of an unobserved (latent) variable on the basis of the responses made on a set of nominal, ordinal, or continuous observed variables. In this article, we introduce LCA in order to demonstrate its usefulness to early adolescence…

  15. Sampling Weights in Latent Variable Modeling

    Science.gov (United States)

    Asparouhov, Tihomir

    2005-01-01

    This article reviews several basic statistical tools needed for modeling data with sampling weights that are implemented in Mplus Version 3. These tools are illustrated in simulation studies for several latent variable models including factor analysis with continuous and categorical indicators, latent class analysis, and growth models. The…

  16. Latent Class and Latent Transition Analysis With Applications in the Social, Behavioral, and Health Sciences

    CERN Document Server

    Collins, Linda M

    2010-01-01

    One of the few books on latent class analysis (LCA) and latent transition analysis (LTA) with a comprehensive treatment of longitudinal latent class models, Latent Class and Latent Transition Analysis reflects improvements in statistical computing as the most up-to-date reference for theoretical, technical, and practical issues in cross-sectional and longitudinal data. Plentiful examples enable the reader to acquire a thorough conceptual and technical understanding and to apply techniques to address empirical research questions. Researchers seeking an advanced introduction to LCA and LTA and g

  17. Latent inhibition in human adults without masking.

    Science.gov (United States)

    Escobar, Martha; Arcediano, Francisco; Miller, Ralph R

    2003-09-01

    Latent inhibition refers to attenuated responding to Cue X observed when the X-outcome pairings are preceded by X-alone presentations. It has proven difficult to obtain in human adults unless the preexposure (X-alone) presentations are embedded within a masking (i.e., distracting) task. The authors hypothesized that the difficulty in obtaining latent inhibition with unmasked tasks is related to the usual training procedures, in which the preexposure and conditioning experiences are separated by a set of instructions. Experiment 1 reports latent inhibition without masking in a task in which preexposure and conditioning occur without interruption. Experiments 2 and 3 demonstrate that this attenuation in responding to target Cue X does not pass a summation test for conditioned inhibition and is context specific, thereby confirming that it is latent inhibition. Experiments 3 and 4 confirm that introducing instructions between preexposure and conditioning disrupts latent inhibition.

  18. Perspective food addiction, caloric restriction, and dopaminergic neurotransmission

    DEFF Research Database (Denmark)

    Stankowska, Arwen Urrsula Malgorzata; Gjedde, Albert

    2013-01-01

    , and reduced activity in prefrontal regions of the cerebral cortex. The neurobiological characteristics suggest that obese people also have a pathological dependence in common with addicts, in the form of food addiction. Malnutrition and dieting both relate to binge eating, possibly as a compensation...... for a reduced cognitive reward condition. The combination of caloric restriction and food addiction imparts a high risk of relapse as a result of further reduction of dopaminergic neurotransmission and the subsequent loss of reward. As with drugs of abuse, ingestion of large quantities of sugar in circumstances...... of uncontrolled eating increases dopamine release in the nucleus accumbens. This and other evidence suggests that abuse of food is a habit learned by means of mechanisms centred in the basal ganglia, with an increased risk of relapse in the presence of associative amplifiers. This risk is predicted...

  19. Measuring the energy spent by parturient women in fasting and in ingesting caloric replacement (HONEY Mensuración de la energia despendida en el ayuno y en el aporte calórico (MIEL en parturientas Mensuração da energia despendida no jejum e no aporte calórico (MEL em parturientes

    Directory of Open Access Journals (Sweden)

    Célia Regina Maganha e Melo

    2007-08-01

    , demostrando el esfuerzo del organismo en compensar la energía gasta.Este estudo tem como proposta mensurar o gasto energético de parturientes de baixo risco gestacional. As participantes foram selecionadas em dois grupos de maneira aleatória e submetidas a jejum (n=15; grupo I e ingestão de mel (n=15; grupo II. Coletaram-se dados mediante valores do sangue capilar e monitor de freqüência cardíaca. Para a análise estatística empregou-se o teste t pareado e o método de Tukey. Os resultados mostraram que a ingestão de mel não provocou sobrecarga na glicemia materna; a resposta do lactato demonstrou que o substrato oferecido foi bem utilizado; os índices de capacidade cardiorrespiratória demonstraram bom desempenho para os dois grupos; o gasto energético total durante o trabalho de parto demonstra que a ingestão de carboidrato tem influência significativa, melhorando o desempenho anaeróbico materno; o grupo que permaneceu em jejum apresentou, imediatamente após o parto, níveis de lactato mais elevados, demonstrando o esforço do organismo para compensar a energia despendida.

  20. Caloric Restriction in Lean and Obese Strains of Laboratory ...

    Science.gov (United States)

    NEW FINDINGS: What is the central question of this study? How do lean and obese rats respond physiologically to caloric restriction? What is the main finding and its importance? Obese rats show marked benefits compared with lean animals. Reduced body fat is associated with improved longevity with caloric restriction (CR) in rodents. Little is known regarding effects of CR in genetically lean versus obese strains. Long-Evans (LE) and Brown Norway (BN) rats make an ideal comparison for a CR study because the percentage body fat of young adult LE rats is double that of BN rats. Male LE and BN rats were either fed ad libitum (AL) or were caloricallyrestricted to 80 or 90% of their AL weight. The percentages of fat, lean and fluid mass were measured non-invasively at 2- to 4-week intervals. Metabolic rate and respiratory quotient were measured after 3, 6, 9 and 12 months of CR. Overall health was scored monthly. The percentage of fat of the LE strain decreased with CR, whereas the percentage of fat of the BN strain remained above the AL group for several months. The percentage of lean mass increased above the AL for both strains subjected to CR. The percentage offluid was unaffected by CR. The average metabolic rate over 22 h of the BN rats subjected to CR was reduced, whereas that of LE rats was increased slightly above the AL group. The respiratory quotient of BN rats wasdecreased with CR. Overall health of the CR LE group was significantly improved compared with t

  1. Low Caloric Sweeteners for Diabetes and Obesity Care and Their

    Directory of Open Access Journals (Sweden)

    Mohammad Asif

    2015-10-01

    Full Text Available Diabetes and obesity are two common human disorders that affecting human health and invite various diseases and disorders in normal body functions. These diseases are very common worldwide. Diabetes occurs when high blood sugar levels develop. This happens when body can’t make and use all of the insulin it needs to blood sugar normally to keep blood sugar levels as normal as possible to control diabetes. Diabetic patients will need to follow a diet plan, do exercise and possibly take insulin injections. As part of eating plan, health care provider, and dietitian may ask to limit the amount of carbohydrates eat each day. Low-calorie sweeteners are one easy tool to help for follow eating plan. Obesity is more susceptible and often been associated with frequent ingestion of high energy food in high amount and high intake of sugars such as fermentable sugars such as sucrose, fructose, glucose, and maltose. Both diseases are may be genetically or due to hormonal imbalances. High energy sweeteners may causes caries in the teeth particularly susceptible to the children. Increased calorie intake associated with sugars and carbohydrates, especially when associated with physical inactivity, has been implicated in obesity. Fortunately, low calorie artificial and natural alternatives of sugars have been developed as alternatives to fermentable sugars and have shown promise in these health issues. Although there are only few artificial sweeteners (saccharin, aspartame, acesulfam potassium, sucralose, cyclamate that have been approved as food additives by the Food and Drug Administration and additional other low-caloric sweeteners (sugar alcohols, neotame, stevia, erythritol, xylitol, tagatose that have FDA-generally recognized as safe. Given the health impact of sugars and other carbohydrates, professionals should be aware of the marketed available low caloric sweeteners and both their benefits and potential risks.

  2. Radiation and energy balance of lettuce culture inside a polyethylene greenhouse Balanço de radiação e energia da cultura de alface em estufa de polietileno

    Directory of Open Access Journals (Sweden)

    Valéria de Almeida Frisina

    1999-10-01

    , saldo de radiação, fluxo de calor no solo e temperatura do ar (seca e úmida nos dois meios. Utilizou-se um Datalogger que operou na freqüência de 1 Hz, armazenando médias de cinco minutos. A partir das integrações diárias das irradiâncias global (K¯ e refletida (K­, verificou-se que a transmissividade média da radiação global (K¯in / K¯ex foi aproximadamente constante, em torno de 79,59%, enquanto a razão das radiações refletidas (K­in / K­ex foi igual a 69,21% com coeficiente de variação de 8,47%. As curvas normalizadas do saldo de radiação de ondas curtas em relação à radiação global (K* / K¯, nos dois meios, mostraram ser aproximadamente constantes no início do ciclo e decrescentes no final. A relação (Rn/ K¯ foi maior no meio externo, em torno de 12%, a partir da fase em que a superfície verde da cultura cobriu o solo. O balanço médio (L* de radiação de ondas longas foi maior no exterior, em torno de 50%. O balanço de energia, estimado em termos de fluxos verticais, mostrou, em média, que: no exterior, 83,07% do saldo de radiação foi convertido em calor latente (LE, 18,00% em fluxo de calor no solo (G e 9,96% em calor sensível (H, enquanto que, no interior da estufa, 58,71% do saldo de radiação foi convertido em LE, 42,68% em H e 28,79% em G.

  3. Balanço de energia e estimativa da evapotranspiração em culturas irrigadas de maracujazeiro pelo método da razão de Bowen Energy balance and estimative of the evapotranspiration of irrigated passionfruit crops by the Bowen ratio method

    Directory of Open Access Journals (Sweden)

    Tonny J. A. Silva

    2007-08-01

    Full Text Available A cultura do maracujazeiro-amarelo tem tido grande expansão da área cultivada no Estado de São Paulo e, apesar da importância da irrigação para a cultura, há poucos estudos sobre sua utilização. Este trabalho foi realizado na área experimental de irrigação, na Fazenda Areão, do Departamento de Engenharia Rural, da Escola Superior de Agricultura "Luiz de Queiroz" - ESALQ/USP (Piracicaba - SP. Foram coletados dados de saldo de radiação, fluxo de calor no solo, gradientes de temperatura e pressão de vapor do ar com o objetivo de avaliar a partição da energia disponível e a evapotranspiração em cultivo de maracujazeiros em dois sistemas de plantio (linhas de cultivo norte-sul e leste-oeste. O método da razão de Bowen foi utilizado na determinação dos fluxos de calor sensível e latente. O saldo de radiação não foi influenciado pelo sistema de plantio, sendo equivalente a 60% da radiação global. O componente de maior contribuição no balanço de energia foi o calor latente de evaporação ocorrendo imediatamente após a chuva ou irrigação. A utilização do modelo de análise e exclusão de intervalos em que o método da Razão de Bowen falha, melhora a estimativa da evapotranspiração.Passionfruit crop has been having great expansion in the cultivated area of São Paulo State and beside the irrigation importance for crop; there are few studies about its utilization. This work was carried out at the experimental irrigation farm of the Engineering Department - College of Agriculture "Luiz de Queiroz" - ESALQ/USP, in Piracicaba, São Paulo State, Brazil. Were collected micrometeorological data from net radiation, soil flux heat, temperature and vapor pressure gradient with the aim to evaluate the partition of available energy and evapotranspiration of passionfruit crop planted under two row directions (North-South and East-West. The Bowen ratio method was used to determine both sensible and latent fluxes. The net

  4. Características químicas de abacaxi 'Pérola' após tratamento com calor e armazenagem em três temperaturas Pineapple 'Pérola' chemical characteristics after rot treatment and storage of three temperature

    Directory of Open Access Journals (Sweden)

    Rosilene Ferreira Souto

    2010-03-01

    Full Text Available Avaliou-se o efeito do tratamento térmico (40ºC por 24 horas e de diferentes temperaturas de armazenamento (8ºC, 14ºC e 25ºC, a 90%UR, na conservação pós-colheita de abacaxis 'Pérola', colhidos no ponto de maturação "pintado". As avaliações foram realizadas no início (0 dia, visando à caracterização inicial dos frutos, e após 1; 5; 9; 13 e 17 dias, quando os mantidos sob refrigeração foram transferidos para condição ambiente (25ºC, 75-80% UR, e avaliados aos 21; 25 e 29 dias. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema fatorial (2x3x9, tendo-se os frutos tratados termicamente ou não, o armazenamento a 25ºC, 14ºC e 8ºC e nove épocas de avaliação. Os frutos foram avaliados quanto à ocorrência de podridões e de escurecimento interno, aparência e coloração da polpa, teores de sólidos solúveis (SS, acidez titulável (AT, açúcares solúveis totais e redutores e ácido ascórbico, além da relação SS/AT. Os resultados indicam que a coloração da polpa se tornou mais amarela durante o período refrigerado, enquanto os valores da AT aumentaram. Neste período, a relação SS/AT reduziu-se, mas aumentou com a transferência dos frutos para o ambiente, enquanto os teores de açúcares solúveis totais e redutores diminuíram, e estabilizaram-se. Os teores de ácido ascórbico mantiveram-se sem diferenças significativas, mas com tendência de aumento. Os frutos mantidos sob refrigeração apresentaram sintomas de injúria pelo frio, que apareceram em 8 dias, após serem levados ao ambiente, e com maior intensidade nos tratados termicamente.The effects of heating the fruits at 40ºC for 24 hours and different storage temperatures (8ºC, 14ºC and 25ºC, at 90% RH to postharvest conservation of 'Pérola' pineapple fruit, harvested on "pintado" maturation stage. The evaluations were carried at the beginning (day 0, for initial characterization of the fruit and after 1, 5, 9, 13

  5. First Versus Second Order Latent Growth Curve Models: Some Insights From Latent State-Trait Theory

    OpenAIRE

    Geiser, Christian; Keller, Brian; Lockhart, Ginger

    2013-01-01

    First order latent growth curve models (FGMs) estimate change based on a single observed variable and are widely used in longitudinal research. Despite significant advantages, second order latent growth curve models (SGMs), which use multiple indicators, are rarely used in practice, and not all aspects of these models are widely understood. In this article, our goal is to contribute to a deeper understanding of theoretical and practical differences between FGMs and SGMs. We define the latent ...

  6. Expected Classification Accuracy using the Latent Distribution

    Directory of Open Access Journals (Sweden)

    Fanmin Guo

    2006-10-01

    Full Text Available Rudner (2001, 2005 proposed a method for evaluating classification accuracy in tests based on item response theory (IRT. In this paper, a latent distribution method is developed. For comparison, both methods are applied to a set of real data from a state test. While the latent distribution method relaxes several of the assumptions needed to apply Rudner's method, both approaches yield extremely comparable results. A simplified approach for applying Rudner's method and a short SPSS routine are presented.

  7. Handbook of latent variable and related models

    CERN Document Server

    Lee, Sik-Yum

    2011-01-01

    This Handbook covers latent variable models, which are a flexible class of models for modeling multivariate data to explore relationships among observed and latent variables.- Covers a wide class of important models- Models and statistical methods described provide tools for analyzing a wide spectrum of complicated data- Includes illustrative examples with real data sets from business, education, medicine, public health and sociology.- Demonstrates the use of a wide variety of statistical, computational, and mathematical techniques.

  8. Use of caloric and noncaloric sweeteners in US consumer packaged foods, 2005-2009.

    Science.gov (United States)

    Ng, Shu Wen; Slining, Meghan M; Popkin, Barry M

    2012-11-01

    Our understanding of the use of caloric and noncaloric sweeteners in the US food supply is limited. This study uses full ingredient list and Nutrition Facts label data from Gladson Nutrition Database and nationally representative purchases of consumer packaged foods from Nielsen Homescan in 2005 through 2009 to understand the use of caloric sweeteners (including fruit juice concentrate) and noncaloric sweeteners in consumer packaged foods. Of the 85,451 uniquely formulated foods purchased during 2005 through 2009, 75% contain sweeteners (68% with caloric sweetener only, 1% with noncaloric sweetener only, 6% with both caloric and noncaloric sweeteners). Caloric sweetener are in >95% of cakes/cookies/pies, granola/protein/energy bars, ready-to-eat cereals, sweet snacks, and sugar-sweetened beverages. Noncaloric sweetener are in >33% of yogurts and sport/energy drinks, 42% of waters (plain or flavored), and most dietetic sweetened beverages. Across unique products, corn syrup is the most commonly listed sweetener, followed by sorghum, cane sugar, high-fructose corn syrup, and fruit juice concentrate. Also, 77% of all calories purchased in the United States in 2005-2009 contained caloric sweeteners and 3% contained noncaloric sweeteners, and 73% of the volume of foods purchased contained caloric sweetener and 15% contained noncaloric sweetener. Trends during this period suggest a shift toward the purchase of noncaloric sweetener-containing products. Our study poses a challenge toward monitoring sweetener consumption in the United States by discussing the need and options available to improve measures of caloric sweetener and noncaloric sweetener and additional requirements on Nutrition Facts labels on consumer packaged foods.

  9. Caloric restriction decreases orthostatic tolerance independently from 6° head-down bedrest.

    Directory of Open Access Journals (Sweden)

    John P Florian

    Full Text Available Astronauts consume fewer calories during spaceflight and return to earth with an increased risk of orthostatic intolerance. Whether a caloric deficiency modifies orthostatic responses is not understood. Thus, we determined the effects of a hypocaloric diet (25% caloric restriction during 6° head down bedrest (an analog of spaceflight on autonomic neural control during lower body negative pressure (LBNP. Nine healthy young men completed a randomized crossover bedrest study, consisting of four (2 weeks each interventions (normocaloric bedrest, normocaloric ambulatory, hypocaloric bedrest, hypocaloric ambulatory, each separated by 5 months. Muscle sympathetic nerve activity (MSNA was recorded at baseline following normocaloric and hypocaloric interventions. Heart rate (HR and arterial pressure were recorded before, during, and after 3 consecutive stages (7 min each of LBNP (-15, -30, -45 mmHg. Caloric and posture effects during LBNP were compared using two-way ANOVA with repeated measures. There was a strong trend toward reduced basal MSNA following caloric restriction alone (normcaloric vs. hypocaloric: 22±3 vs. 14±4 burst/min, p = 0.06. Compared to the normocaloric ambulatory, both bedrest and caloric restriction were associated with lower systolic blood pressure during LBNP (p<0.01; however, HR responses were directionally opposite (i.e., increase with bedrest, decrease with caloric restriction. Survival analysis revealed a significant reduction in orthostatic tolerance following caloric restriction (normocaloric finishers: 12/16; hypocaloric finishers: 6/16; χ2, p = 0.03. Caloric restriction modifies autonomic responses to LBNP, which may decrease orthostatic tolerance after spaceflight.

  10. Automobilismo: no calor da competição Automovilismo: en el calor de la competición Car racing: in the heat of competition

    OpenAIRE

    Luiz Oswaldo Carneiro Rodrigues; Flávio de Castro Magalhães

    2004-01-01

    O presente artigo questiona o papel do calor como um fator de risco adicional para o acidente que vitimou Ayrton Senna. O automobilismo de competição constitui um desafio biológico, uma situação estressante do ponto de vista mental e físico. A manutenção da performance depende da disponibilidade de carboidratos e oxigênio, hidratação adequada e temperatura interna constante entre 37 e 38 graus centígrados. A dissipação do calor produzido pelo metabolismo ocorre através do aumento do fluxo de ...

  11. Dissecting and Targeting Latent Metastasis

    Science.gov (United States)

    2014-09-01

    National Academy of Sciences of the United States of America 100, 3983-3988 (2003). 9. J. Holash, P. C. Maisonpierre, D. Compton , P. Boland, C. R...80 00 00 D E Click # QC20111130154029 Wed, Nov 30, 2011 15:40:32 Em filter=Open Bin:M (8), FOV12.8, f1, 10s Camera : IS0702N4087, Spectral Instruments...did not trigger apoptosis (Figure S2Q). These results suggested that plasmin acting through unknown substrates kills infiltrating cancer cells in the

  12. Habituation, latent inhibition, and extinction.

    Science.gov (United States)

    Jordan, Wesley P; Todd, Travis P; Bucci, David J; Leaton, Robert N

    2015-06-01

    In two conditioned suppression experiments with a latent inhibition (LI) design, we measured the habituation of rats in preexposure, their LI during conditioning, and then extinction over days. In the first experiment, lick suppression, the preexposed group (PE) showed a significant initial unconditioned response (UR) to the target stimulus and significant long-term habituation (LTH) of that response over days. The significant difference between the PE and nonpreexposed (NPE) groups on the first conditioning trial was due solely to the difference in their URs to the conditioned stimulus (CS)-a habituated response (PE) and an unhabituated response (NPE). In the second experiment, bar-press suppression, little UR to the target stimulus was apparent during preexposure, and no detectable LTH. Thus, there was no difference between the PE and NPE groups on the first conditioning trial. Whether the UR to the CS confounds the interpretation of LI (Exp. 1) or not (Exp. 2) can only be known if the UR is measured. In both experiments, LI was observed in acquisition. Also in both experiments, rats that were preexposed and then conditioned to asymptote were significantly more resistant to extinction than were the rats not preexposed. This result contrasts with the consistently reported finding that preexposure either produces less resistance to extinction or has no effect on extinction. The effect of stimulus preexposure survived conditioning to asymptote and was reflected directly in extinction. These two experiments provide a cautionary procedural note for LI experiments and have shown an unexpected extinction effect that may provide new insights into the interpretation of LI.

  13. Caloric stimulation with near infrared radiation does not induce paradoxical nystagmus.

    Science.gov (United States)

    Walther, L E; Asenov, D R; Di Martino, E

    2011-04-01

    Near infrared radiation can be used for warm stimulation in caloric irrigation of the equilibrium organ. Aim of this study was to determine whether near infrared radiation offers effective stimulation of the vestibular organ, whether it is well tolerated by the patients and especially whether it is a viable alternative to warm air stimulation in patients with defects of the tympanic membrane and radical mastoid cavities. Patients with perforations of the tympanic membrane (n = 15) and with radical mastoid cavities (n = 13) were tested both with near infrared radiation and warm dry air. A caloric-induced nystagmus could be seen equally effectively and rapidly in all patients. Contrary to stimulation with warm dry air, no paradoxical nystagmus was observed following caloric irrigation with a warm stimulus (near infrared radiation). Results of a questionnaire showed excellent patient acceptance of near infrared stimulation with no arousal effects or unpleasant feeling. In conclusion, near infrared radiation proved to be an alternative method of caloric irrigation to warm dry air in patients with tympanic membrane defects and radical mastoid cavities. Near infrared radiation is pleasant, quick, contact free, sterile and quiet. With this method an effective caloric warm stimulus is available. If near infrared radiation is used for caloric stimulus no evaporative heat loss occurs.

  14. Comparison of standardized versus individualized caloric prescriptions in the nutritional rehabilitation of inpatients with anorexia nervosa

    Science.gov (United States)

    Haynos, Ann F.; Snipes, Cassandra; Guarda, Angela; Mayer, Laurel E.; Attia, Evelyn

    2015-01-01

    Objective Sparse research informs how caloric prescriptions should be advanced during nutritional rehabilitation of inpatients with anorexia nervosa (AN). This study compared the impact of a standardized caloric increase approach, in which increases occurred on a predetermined schedule, to an individualized approach, in which increases occurred only following insufficient weight gain, on rate, pattern, and cumulative amount of weight gain and other weight restoration outcomes. Method This study followed a natural experiment design comparing AN inpatients consecutively admitted before (n = 35) and after (n = 35) an institutional change from individualized to standardized caloric prescriptions. Authors examined the impact of prescription plan on weekly weight gain in the first treatment month using multilevel modeling. Within a subsample remaining inpatient through weight restoration (n = 40), multiple regressions examined the impact of caloric prescription plan on time to weight restoration, length of hospitalization, maximum caloric prescription, discharge BMI, and incidence of activity restriction and edema. Results There were significant interactions between prescription plan and quadratic time on average weekly weight gain (p = .03) and linear time on cumulative weekly weight gain (p < .001). Under the standardized plan, patients gained in an accelerated curvilinear pattern (p = .04) and, therefore, gained cumulatively greater amounts of weight over time (p < .001). Additionally, 30% fewer patients required activity restriction under the standardized plan. Discussion Standardized caloric prescriptions may confer advantage by facilitating accelerated early weight gain and lower incidence of bed rest without increasing the incidence of refeeding syndrome. PMID:26769581

  15. Fasting and Caloric Restriction in Cancer Prevention and Treatment.

    Science.gov (United States)

    Brandhorst, Sebastian; Longo, Valter D

    Cancer is the second leading cause of death in the USA and among the leading major diseases in the world. It is anticipated to continue to increase because of the growth of the aging population and prevalence of risk factors such as obesity, smoking, and/or poor dietary habits. Cancer treatment has remained relatively similar during the past 30 years with chemotherapy and/or radiotherapy in combination with surgery remaining the standard therapies although novel therapies are slowly replacing or complementing the standard ones. According to the American Cancer Society, the dietary recommendation for cancer patients receiving chemotherapy is to increase calorie and protein intake. In addition, there are no clear guidelines on the type of nutrition that could have a major impact on cancer incidence. Yet, various forms of reduced caloric intake such as calorie restriction (CR) or fasting demonstrate a wide range of beneficial effects able to help prevent malignancies and increase the efficacy of cancer therapies. Whereas chronic CR provides both beneficial and detrimental effects as well as major compliance challenges, periodic fasting (PF), fasting-mimicking diets (FMDs), and dietary restriction (DR) without a reduction in calories are emerging as interventions with the potential to be widely used to prevent and treat cancer. Here, we review preclinical and preliminary clinical studies on dietary restriction and fasting and their role in inducing cellular protection and chemotherapy resistance.

  16. Achados à prova calórica e canal semicircular acometido na vertigem posicional paroxística benigna Caloric test results and damaged semicircular canal in benign positional paroxysmal vertigo

    Directory of Open Access Journals (Sweden)

    Andréa Manso

    2009-01-01

    Full Text Available OBJETIVO: Caracterizar os achados da prova calórica em pacientes com vertigem posicional paroxística benigna, segundo o canal semicircular comprometido. MÉTODOS: Foram analisados 1033 prontuários de pacientes submetidos à pesquisa de nistagmo posicional e de posicionamento e à eletronistagmografia. Os achados da prova calórica, de acordo com os canais semicirculares acometidos, foram submetidos à análise estatística. RESULTADOS: No comprometimento de canal posterior, houve prevalência de normorreflexia (pPURPOSE: To characterize caloric test results in benign paroxysmal positional vertigo patients, according to the damaged semicircular canal. METHODS: The data of 1033 patients submitted to Dix-Hallpike testing, positional nystagmus and electronystagmography were analyzed. Caloric test results were compared to the damaged semicircular canals and were submitted to statistical analysis. RESULTS: In cases with posterior canal damage, there was prevalence of normal responses compared to abnormal results (p<0.0001; hypo activity was more prevalent than hyperactivity (p<0.0001 and directional preponderance (p<0.0001, and hyperactivity more prevalent than directional preponderance (p<0.0001. In cases with lateral canal damage, normal responses were more prevalent than hypo activity (p<0.0001 and hyperactivity (p<0.0001; there was a tendency of prevalence of hypo activity over hyperactivity (p=0.0771, and directional preponderance was not observed. In cases with anterior canal damage, normal responses were more prevalent than hypo activity (p<0.0001; hyperactivity and directional preponderance were not observed. CONCLUSION: In the caloric test of benign positional paroxysmal vertigo patients, normal responses, hypo activity, hyperactivity or directional preponderance of post-caloric nystagmus occur in decreasing order of prevalence when the posterior canal is damaged; normal responses are more prevalent than hypoactive or hyperactive caloric

  17. Moisture adsorption characteristics of ginger slices Características de adsorção de umidade de gengibre em fatias

    Directory of Open Access Journals (Sweden)

    Joseph Alakali

    2009-03-01

    Full Text Available The moisture adsorption characteristics of dried ginger slices was studied to determine the effect of storage conditions on moisture adsorption for the purpose of shelf life prediction, selection of appropriate packaging materials, evaluate the goodness-of-fit of sorption models, and determine the thermodynamics of moisture adsorption for application in drying. There was a highly significant effect (p As características da adsorção de umidade de amostras de gengibre secas foram estudadas para se determinar o efeito das condições de armazenamento com o propósito de se prever a vida de prateleira ou validade, a seleção de materiais apropriados para empacotamento, avaliar a bondade de ajuste dos modelos de sorção e determinar a termodinâmica da adsorção de umidade para aplicação em secagem. Houve um efeito significativo (p < 0,05 da atividade de água, da temperatura e do pré-tratamento sobre o teor de umidade de equilíbrio higroscópico das amostras de gengibre secas. Sob atividade de água constante (a w, o teor de umidade de equilíbrio higroscópico (CEM diminuiu com o aumento da temperatura. O teor de umidade de equilíbrio higroscópico de todas as amostras aumentou com o aumento da atividade de água, sob temperatura constante. A umidade de sorção das amostras de gengibre com casca foi maior do que a das amostras de gengibre sem casca enquanto que a das amostras de gengibre não escaldo com e sem casca foi maior do que a das amostras de gengibre escaldado com e sem casca. A equação de Henderson permite previsões mais exatas das isotermas com o menor valor de média quadrática percentual (%RMS e, portanto, descreve melhor os dados de adsorção dos modelos de Guggenheim Anderson De-Boer (GAB, Oswin e Halsey, nesta ordem. A umidade de monocamada, em geral, diminuiu com a temperatura em todas as amostras. O calor isostérico diminuiu quando o teor de umidade se aproximou do valor assimptótico ou o calor latente de

  18. Human Cytomegalovirus Manipulation of Latently Infected Cells

    Directory of Open Access Journals (Sweden)

    John H. Sinclair

    2013-11-01

    Full Text Available Primary infection with human cytomegalovirus (HCMV results in the establishment of a lifelong infection of the host which is aided by the ability of HCMV to undergo a latent infection. One site of HCMV latency in vivo is in haematopoietic progenitor cells, resident in the bone marrow, with genome carriage and reactivation being restricted to the cells of the myeloid lineage. Until recently, HCMV latency has been considered to be relatively quiescent with the virus being maintained essentially as a “silent partner” until conditions are met that trigger reactivation. However, advances in techniques to study global changes in gene expression have begun to show that HCMV latency is a highly active process which involves expression of specific latency-associated viral gene products which orchestrate major changes in the latently infected cell. These changes are argued to help maintain latent infection and to modulate the cellular environment to the benefit of latent virus. In this review, we will discuss these new findings and how they impact not only on our understanding of the biology of HCMV latency but also how they could provide tantalising glimpses into mechanisms that could become targets for the clearance of latent HCMV.

  19. Cardioprotective Signature of Short-Term Caloric Restriction.

    Directory of Open Access Journals (Sweden)

    Hossein Noyan

    Full Text Available To understand the molecular pathways underlying the cardiac preconditioning effect of short-term caloric restriction (CR.Lifelong CR has been suggested to reduce the incidence of cardiovascular disease through a variety of mechanisms. However, prolonged adherence to a CR life-style is difficult. Here we reveal the pathways that are modulated by short-term CR, which are associated with protection of the mouse heart from ischemia.Male 10-12 wk old C57bl/6 mice were randomly assigned to an ad libitum (AL diet with free access to regular chow, or CR, receiving 30% less food for 7 days (d, prior to myocardial infarction (MI via permanent coronary ligation. At d8, the left ventricles (LV of AL and CR mice were collected for Western blot, mRNA and microRNA (miR analyses to identify cardioprotective gene expression signatures. In separate groups, infarct size, cardiac hemodynamics and protein abundance of caspase 3 was measured at d2 post-MI.This short-term model of CR was associated with cardio-protection, as evidenced by decreased infarct size (18.5±2.4% vs. 26.6±1.7%, N=10/group; P=0.01. mRNA and miR profiles pre-MI (N=5/group identified genes modulated by short-term CR to be associated with circadian clock, oxidative stress, immune function, apoptosis, metabolism, angiogenesis, cytoskeleton and extracellular matrix (ECM. Western blots pre-MI revealed CR-associated increases in phosphorylated Akt and GSK3ß, reduced levels of phosphorylated AMPK and mitochondrial related proteins PGC-1α, cytochrome C and cyclooxygenase (COX IV, with no differences in the levels of phosphorylated eNOS or MAPK (ERK1/2; p38. CR regimen was also associated with reduced protein abundance of cleaved caspase 3 in the infarcted heart and improved cardiac function.

  20. Palatable Hyper-Caloric Foods Impact on Neuronal Plasticity

    Science.gov (United States)

    Morin, Jean-Pascal; Rodríguez-Durán, Luis F.; Guzmán-Ramos, Kioko; Perez-Cruz, Claudia; Ferreira, Guillaume; Diaz-Cintra, Sofia; Pacheco-López, Gustavo

    2017-01-01

    Neural plasticity is an intrinsic and essential characteristic of the nervous system that allows animals “self-tuning” to adapt to their environment over their lifetime. Activity-dependent synaptic plasticity in the central nervous system is a form of neural plasticity that underlies learning and memory formation, as well as long-lasting, environmentally-induced maladaptive behaviors, such as drug addiction and overeating of palatable hyper-caloric (PHc) food. In western societies, the abundance of PHc foods has caused a dramatic increase in the incidence of overweight/obesity and related disorders. To this regard, it has been suggested that increased adiposity may be caused at least in part by behavioral changes in the affected individuals that are induced by the chronic consumption of PHc foods; some authors have even drawn attention to the similarity that exists between over-indulgent eating and drug addiction. Long-term misuse of certain dietary components has also been linked to chronic neuroimmune maladaptation that may predispose individuals to neurodegenerative conditions such as Alzheimer’s disease. In this review article, we discuss recent evidence that shows how consumption of PHc food can cause maladaptive neural plasticity that converts short-term ingestive drives into compulsive behaviors. We also discuss the neural mechanisms of how chronic consumption of PHc foods may alter brain function and lead to cognitive impairments, focusing on prenatal, childhood and adolescence as vulnerable neurodevelopmental stages to dietary environmental insults. Finally, we outline a societal agenda for harnessing permissive obesogenic environments. PMID:28261067

  1. Controle multivariável em redes de trocadores de calor com bypasses.

    OpenAIRE

    Fabio Delatore

    2011-01-01

    Atualmente, existe uma grande variedade de metodologias de controle que poderiam ser utilizadas e aplicadas a processos industriais. Algumas destas metodologias têm um projeto complexo, exigindo um estudo extra de engenharia para projetar um controlador com um desempenho excelente. Outros controladores não apresentam um desempenho tão bom, embora apresentem um projeto extremamente simples. Entre a mais simples e a mais complexa metodologia, existem soluções de controle intermediárias, baseada...

  2. Heat pumps in dairy property; Bombas de calor em propriedade leiteira

    Energy Technology Data Exchange (ETDEWEB)

    Baldassin Junior, Ricardo [Universidade Estadual de Campinas (FEM/UNICAMP), SP (Brazil). Fac. de Engenharia Mecanica. Planejamento de Sistemas Energeticos; Cortez, Luis Augusto Barbosa; Jordan, Rodrigo Aparecido; Ferreira, Tamara Aurora Bartholomei [Universidade Estadual de Campinas (FEAGRI/UNICAMP), SP (Brazil). Fac. de Engenharia Agricola. Dept. de Construcoes Rurais e Ambiencia; Neves Filho, Lincoln de Carmargo; Silveira Junior, Vivaldo [Universidade Estadual de Campinas (FEA/UNICAMP), SP (Brazil). Fac. de Engenharia de Alimentos

    2006-07-01

    Milk is a prominence product of Brazilian agriculture, with about 2/3 of the rural properties dedicated to the milkmaid cattle breeding, the second bigger flock of the world and a representative participation in the national economy. In spite of its size, the sector still suffers of low productivity, high costs, the instability of prices and technological delay, which resulted in many producers have abandoned its activities in consequence of this new competitive scenario. Nowadays, subjects as, the rational use of energy and intensive application of technology have been hardly discussed, and indicated, as important aspects to obtain high productivity gains. In this work, it is presented an evaluation of the use of energy in a milkmaid which processes cooled raw milk in Morungaba city, Sao Paulo state, Brazil, with a 1.000 liters daily production, making use of the three main processes (cooling, milking system and water heating). Aiming at to promote the rational use of energy, it was realized in this property, an adequacy in the tank milk cooler to utilize the condensation heat, of the refrigeration system, to heat cleanness water (operation according to a heat pump). Through this practical, it was objectified the exclusion of the use of the electric resistance in the heating process for term -accumulation (300 liters/day), promoting consumption reduction and rational use of energy. (author)

  3. Learning with Latent Factors in Time Series

    CERN Document Server

    Jalali, Ali

    2011-01-01

    This paper considers the problem of learning, from samples, the dependency structure of a system of linear stochastic differential equations, when some of the variables are latent. In particular, we observe the time evolution of some variables, and never observe other variables; from this, we would like to find the dependency structure between the observed variables -- separating out the spurious interactions caused by the (marginalizing out of the) latent variables' time series. We develop a new method, based on convex optimization, to do so in the case when the number of latent variables is smaller than the number of observed ones. For the case when the dependency structure between the observed variables is sparse, we theoretically establish a high-dimensional scaling result for structure recovery. We verify our theoretical result with both synthetic and real data (from the stock market).

  4. Effects of caloric vestibular stimulation on serotoninergic system in the media vestibular nuclei of guinea pigs

    Institute of Scientific and Technical Information of China (English)

    MA Fu-rong; LIU Jun-xiu; LI Xue-pei; MAO Jian-jun; ZHANG Qun-dan; JIA Hong-bo; MAO Lan-quan; ZHAO Rui

    2007-01-01

    Background Anatomic and electrophysiological studies have revealed that the neurons located in the media vestibular nuclei (MVN) receive most of the sensory vestibular input coming from the ipsilateral labyrinth and the responses of MVN neurons to caloric stimulation directly reflect changes in primary vestibular afferent activity. The aim of this study was to clarify the intrinsic characteristics of serotonin (5-hydroxytryptamine, 5-HT) release in the MVN during the period of vertigo induced by caloric stimulation.Methods We used an in vivo microdialysis technique to examine the effects of caloric stimulation on the serotoninergic system in MVN. Twenty four guinea pigs were randomly divided into the groups of irrigation of the ear canal with hot water (n=6), ice water (n=6) and 37℃ water (n=4), and the groups of irrigation of the auricle with hot water (n=4) and ice water (n=4), according to different caloric vestibular stimulation. We examined the animal's caloric nystagmus with a two-channel electronystagmographic recorder (ENG), and meanwhile examine serotonin (5-hydroxytryptamine, 5-HT) level in the MVN with microdialysis technique after caloric stimulation. Results In the caloric test the hot water (44℃) irrigation of the right external auditory canal induced horizontal nystagmus towards the right side lasting about 60 seconds and the ice water irrigation of the right external auditory canal induced it towards the left side lasting for about 90 seconds. No nystagmus was induced by 37℃ water irrigation of the external ear canal. Therefore, it was used as a negative control stimulation to the middle ear. The MVN 5-HT levels significantly increased in the first 5-minute collecting interval and increased to 254% and 189% of the control group in the second collecting interval in response to caloric vestibular stimulation with ice water and hot water respectively. The serotonin release was not distinctly changed by the irrigation of the auricle with ice water

  5. The Lexicocalorimeter: Gauging public health through caloric input and output on social media

    Science.gov (United States)

    Alajajian, Sharon E.; Williams, Jake Ryland; Reagan, Andrew J.; Alajajian, Stephen C.; Frank, Morgan R.; Mitchell, Lewis; Lahne, Jacob; Danforth, Christopher M.; Dodds, Peter Sheridan

    2017-01-01

    We propose and develop a Lexicocalorimeter: an online, interactive instrument for measuring the “caloric content” of social media and other large-scale texts. We do so by constructing extensive yet improvable tables of food and activity related phrases, and respectively assigning them with sourced estimates of caloric intake and expenditure. We show that for Twitter, our naive measures of “caloric input”, “caloric output”, and the ratio of these measures are all strong correlates with health and well-being measures for the contiguous United States. Our caloric balance measure in many cases outperforms both its constituent quantities; is tunable to specific health and well-being measures such as diabetes rates; has the capability of providing a real-time signal reflecting a population’s health; and has the potential to be used alongside traditional survey data in the development of public policy and collective self-awareness. Because our Lexicocalorimeter is a linear superposition of principled phrase scores, we also show we can move beyond correlations to explore what people talk about in collective detail, and assist in the understanding and explanation of how population-scale conditions vary, a capacity unavailable to black-box type methods. PMID:28187216

  6. A Biomechanical Model of the Inner Ear: Numerical Simulation of the Caloric Test

    Directory of Open Access Journals (Sweden)

    Shuang Shen

    2013-01-01

    Full Text Available Whether two vertical semicircular canals can receive thermal stimuli remains controversial. This study examined the caloric response in the three semicircular canals to the clinical hot caloric test using the finite element method. The results of the developed model showed the horizontal canal (HC cupula maximally deflected to the utricle side by approximately 3 μm during the hot supine test. The anterior canal cupula began to receive the caloric stimuli about 20 s after the HC cupula, and it maximally deflected to the canal side by 0.55 μm. The posterior canal cupula did not receive caloric stimuli until approximately 40 s after the HC cupula, and it maximally deflected to the canal side by 0.34 μm. Although the endolymph flow and the cupular deformation change with respect to the head position during the test, the supine test ensures the maximal caloric response in the HC, but no substantial improvement for the responses of the two vertical canals was observed. In conclusion, while the usual supine test is the optimum test for evaluating the functions of the inner ear, more irrigation time is needed in order to effectively clinically examine the vertical canals.

  7. A biomechanical model of the inner ear: numerical simulation of the caloric test.

    Science.gov (United States)

    Shen, Shuang; Liu, Yingxi; Sun, Xiuzhen; Zhao, Wei; Su, Yingfeng; Yu, Shen; Liu, Wenlong

    2013-01-01

    Whether two vertical semicircular canals can receive thermal stimuli remains controversial. This study examined the caloric response in the three semicircular canals to the clinical hot caloric test using the finite element method. The results of the developed model showed the horizontal canal (HC) cupula maximally deflected to the utricle side by approximately 3 μm during the hot supine test. The anterior canal cupula began to receive the caloric stimuli about 20 s after the HC cupula, and it maximally deflected to the canal side by 0.55 μm. The posterior canal cupula did not receive caloric stimuli until approximately 40 s after the HC cupula, and it maximally deflected to the canal side by 0.34 μm. Although the endolymph flow and the cupular deformation change with respect to the head position during the test, the supine test ensures the maximal caloric response in the HC, but no substantial improvement for the responses of the two vertical canals was observed. In conclusion, while the usual supine test is the optimum test for evaluating the functions of the inner ear, more irrigation time is needed in order to effectively clinically examine the vertical canals.

  8. Latent Fingerprint Matching: Performance Gain via Feedback from Exemplar Prints.

    Science.gov (United States)

    Arora, Sunpreet S; Liu, Eryun; Cao, Kai; Jain, Anil K

    2014-12-01

    Latent fingerprints serve as an important source of forensic evidence in a court of law. Automatic matching of latent fingerprints to rolled/plain (exemplar) fingerprints with high accuracy is quite vital for such applications. However, latent impressions are typically of poor quality with complex background noise which makes feature extraction and matching of latents a significantly challenging problem. We propose incorporating top-down information or feedback from an exemplar to refine the features extracted from a latent for improving latent matching accuracy. The refined latent features (e.g. ridge orientation and frequency), after feedback, are used to re-match the latent to the top K candidate exemplars returned by the baseline matcher and resort the candidate list. The contributions of this research include: (i) devising systemic ways to use information in exemplars for latent feature refinement, (ii) developing a feedback paradigm which can be wrapped around any latent matcher for improving its matching performance, and (iii) determining when feedback is actually necessary to improve latent matching accuracy. Experimental results show that integrating the proposed feedback paradigm with a state-of-the-art latent matcher improves its identification accuracy by 0.5-3.5 percent for NIST SD27 and WVU latent databases against a background database of 100k exemplars.

  9. Efecto del calor aportado en recargues nanoestructurados base hierro

    Directory of Open Access Journals (Sweden)

    Agustín Gualco

    2013-12-01

    Full Text Available En los últimos años se han desarrollado consumibles de soldadura que depositan recubrimientos duros de aleaciones base hierro nanoestructuradas de gran resistencia al desgaste abrasivo. Las resistencias al desgaste erosivo y abrasivo están controladas principalmente por la composición química y la microestructura. A su vez, la microestructura del metal depositado puede presentar variaciones con el procedimiento de soldadura empleado, especialmente en relación al aporte térmico. Los parámetros operativos que definen el aporte térmico (tensión, corriente y velocidad de soldadura afectan aspectos como la geometría del cordón (ancho, penetración y sobremonta y la dilución con el material base. El propósito de este trabajo fue estudiar el efecto del calor aportado sobre las características geométricas del cordón, la dilución y la evolución microestructural de una aleación nanoestructurada base hierro, depositada por FCAW. Se soldaron muestras con aportes térmicos de entre 0,5 y 3,5 kJ/mm. Sobre cada cupón soldado se realizó un relevamiento dimensional, se analizó la composición química y se caracterizó la microestructura usando microscopías óptica y electrónica de barrido y difracción de rayos X. También se midieron la microdureza del depósito, el tamaño de cristalita y el grado de dilución. Se observó una gran influencia de las condiciones de proceso sobre la geometría del cordón. La dilución varió entre un 30 y un 40%, la microdureza del depósito se encontró entre 800 y 870 HV1 y el tamaño de cristalita osciló entre 105 y 130 nm, en función de las variables de proceso empleadas. Las mayores durezas y los menores tamaños de cristalita se obtuvieron con el menor aporte térmico, asociado a una menor dilución.

  10. Heat and mass transfer during the warming of a bottle of beer = Transferência de calor e massa durante o aquecimento de uma garrafa de cerveja

    Directory of Open Access Journals (Sweden)

    Cláudio Vinicius Barbosa Monteiro

    2010-07-01

    Full Text Available The warming of a bottle of beer during a Friday evening happy hour directly involves transport phenomena, such as mass transfer due to condensation of air humidity on the bottle surface and heat transfer from the ambient to the bottle, which occurs by free convection and water condensation. Both processes happen simultaneously and are directly associated with the heat and mass transfer coefficients involved, which are affected by the ambient humidity and temperature. Several runs were made in several ambient conditions by exposing a cold bottle of beer to varied temperature and humidity and measuring the temperature of beer and the mass of water condensed on the bottle surface over time. From these measures, a theoretical and experimental methodology was developed and applied for the evaluation of the heat and mass transfer coefficients that govern this process. Both the relative humidity and ambient temperature exert a significant influence on the convective heat transfer coefficient. However, the mass transfer coefficient is affected only by the temperature.O aquecimento de uma garrafa de cerveja num “happy-hour” de sexta a tarde envolve diretamente os fenômenos de transferência de massa, devido à condensação da umidade do ar na superfície da garrafa, e de transferência de calor do meio para a garrafa, que ocorre por convecção natural e por condensação de vapor de água. Ambos os processos ocorrem simultaneamente e estão diretamente associados aos coeficientes de transferência de calor e massa envolvidos na dinâmica destes fenômenos e sofrem influência direta da umidade e temperatura ambientes. Neste contexto, efetuaram-se ensaios em diversas condições de temperatura e umidade ambientes, expondo-se uma garrafa de cerveja gelada ao ambiente e medindo-se a temperatura da cerveja e a massa de água condensada ao longo do tempo. A partir destas medidas, desenvolveu-se uma metodologia teórico-experimental que proporcionou a

  11. Determinación del calor de fraguado de cemento por icrocalorimetría

    Directory of Open Access Journals (Sweden)

    Liliana Girlado G.

    2010-07-01

    Full Text Available Se determina el calor de fraguado del cemento Río Claro tipo III (Río Claro, Antioquia, Colombia por microcalorimetría de conducción de calor; así como también los efectos de la glucosa y de la sacarosa en el proceso de fraguado de este material. Al emplear 0,15 y 0,05% ( % en peso de estos aditivos en la preparación de las pastas, se observan retardos considerables en el fraguado de las mismas. Los aditivos también modifican el calor de fraguado: la pasta libre de estos presenta un valor de 38,03 J/g en tanto que la adición de glucosa y sacarosa producen valores menores, excepto en el caso de la sacarosa al 0,05% donde se observa un efecto térmico de 55.80 J/s,

  12. Magneto-Caloric Effect of Gd5Si2Ge2Compounds under Different Processing Conditions

    Institute of Scientific and Technical Information of China (English)

    Zeng Hong; Yue Ming; Niu Peili; Zhang Jiuxing

    2004-01-01

    The magneto-caloric effect of Gd5 Si2Ge2 compounds produced by various techniques is investigated in terms of their magnetization behaviors in the magnetic field from 0 to 2.0 T.The studied materials include arc-melted, annealed and sintered alloys.The results demonstrate that the Gd5Si2Ge2 alloys obtained under different processing conditions possess distinct magneto-caloric effect due to their various microstructures.Proper annealing treatment can enhance the magneto-caloric effect of the alloy remarkably.While the sintered alloy bears relatively lower value of magnetic entropy change ( △ SM) than arc-melted one.The magnetic entropy change of the annealed Gd5 Si2Ge2 alloy arrives the arrives the maximum value of - △SM = 15.29 J· kg-1· K-1 for magnetic field change under 2.0 T in the present work.

  13. Effect of gravity on the caloric stimulation of the inner ear

    Science.gov (United States)

    Kassemi, Mohammad; Deserranno, Dimitri; Oas, John G.

    2004-01-01

    Robert Barany won the 1914 Nobel Prize in medicine for his convection hypothesis for caloric stimulation. Microgravity caloric tests aboard the 1983 SpaceLab 1 mission produced nystagmus results that contradicted the basic premise of Barany's convection theory. In this paper, we present a fluid structural analysis of the caloric stimulation of the lateral semicircular canal. Direct numerical simulations indicate that on earth, natural convection is the dominant mechanism for endolymphatic flow. However, in the microgravity environment of orbiting spacecraft, where buoyancy effects are mitigated, an expansive convection becomes the sole mechanism for producing endolymph motion and cupular displacement. Transient 1 g and microgravity case studies are presented to delineate the different dynamic behaviors of the 1 g and microgravity endolymphatic flows. The associated fluid-structural interactions are also analyzed based on the time evolution of cupular displacements.

  14. Efecte de l'estrès per calor en cabres productores de llet

    OpenAIRE

    Salama, Ahmed A. K.

    2015-01-01

    A causa del canvi climàtic, s'espera una major freqüència i intensitat de les onades de calor en el futur. Una investigació ha estudiat els efectes de l'estrès per calor sobre la producció de cabres lleteres de raça Murciano-Granadina i els efectes de l'addició de l'oli de soja i del propilenglicol a la seva dieta. Els resultats mostren diferències evidents en les característiques de la llet de les cabres sotmeses a estrès per calor, així com beneficis de l'ús d'oli de soja per millorar les p...

  15. Dietary restriction with and without caloric restriction for healthy aging [version 1; referees: 3 approved

    Directory of Open Access Journals (Sweden)

    Changhan Lee

    2016-01-01

    Full Text Available Caloric restriction is the most effective and reproducible dietary intervention known to regulate aging and increase the healthy lifespan in various model organisms, ranging from the unicellular yeast to worms, flies, rodents, and primates. However, caloric restriction, which in most cases entails a 20–40% reduction of food consumption relative to normal intake, is a severe intervention that results in both beneficial and detrimental effects. Specific types of chronic, intermittent, or periodic dietary restrictions without chronic caloric restriction have instead the potential to provide a significant healthspan increase while minimizing adverse effects. Improved periodic or targeted dietary restriction regimens that uncouple the challenge of food deprivation from the beneficial effects will allow a safe intervention feasible for a major portion of the population. Here we focus on healthspan interventions that are not chronic or do not require calorie restriction.

  16. Dish-mounted latent heat buffer storage

    Science.gov (United States)

    Manvi, R.

    1981-01-01

    Dish-mounted latent heat storage subsystems for Rankine, Brayton, and Stirling engines operating at 427 C, 816 C, and 816 C respectively are discussed. Storage requirements definition, conceptual design, media stability and compatibility tests, and thermal performance analyses are considered.

  17. Random Effect and Latent Variable Model Selection

    CERN Document Server

    Dunson, David B

    2008-01-01

    Presents various methods for accommodating model uncertainty in random effects and latent variable models. This book focuses on frequentist likelihood ratio and score tests for zero variance components. It also focuses on Bayesian methods for random effects selection in linear mixed effects and generalized linear mixed models

  18. Forensic Chemistry: The Revelation of Latent Fingerprints

    Science.gov (United States)

    Friesen, J. Brent

    2015-01-01

    The visualization of latent fingerprints often involves the use of a chemical substance that creates a contrast between the fingerprint residues and the surface on which the print was deposited. The chemical-aided visualization techniques can be divided into two main categories: those that chemically react with the fingerprint residue and those…

  19. Generalized Structured Component Analysis with Latent Interactions

    Science.gov (United States)

    Hwang, Heungsun; Ho, Moon-Ho Ringo; Lee, Jonathan

    2010-01-01

    Generalized structured component analysis (GSCA) is a component-based approach to structural equation modeling. In practice, researchers may often be interested in examining the interaction effects of latent variables. However, GSCA has been geared only for the specification and testing of the main effects of variables. Thus, an extension of GSCA…

  20. Charging characteristics of ionographic latent images

    Energy Technology Data Exchange (ETDEWEB)

    Fallone, B.G.; Podgorsak, E.B.

    The charging characteristics of ionographic latent images are discussed in terms of the saturation characteristics of ionographic chambers. It is shown that latent images are essentially foil electrets with surface charge densities modulated by the x-ray transmission through the object. Empirical methods for the calculation of saturation current densities and extrapolated electric fields are given. Both the saturation current density and the extrapolated field consist of two components: one, which is linear with the air gap thickness, is produced by primary photon interactions in the chamber-sensitive volume; the other, exhibiting an exponential saturation, is attributed to photoelectrons backscattered from the polarizing electrode into the chamber-sensitive volume. The minimum applied electric field needed for an optimized charge collection in the ionographic chamber is presented in terms of both the characteristic polarization time and the electret relaxation time. The maximum possible surface charge density in the latent image is calculated, first exhibiting direct proportionality with the polarizing voltage V0, and then following a V0 (1/2) dependence for voltages larger than the breakpoint voltage. The optimum exposure for latent image production is calculated. Exposures below this optimum give insufficient charge densities for subsequent development, while exposures above it degrade the image and eventually result in a uniform foil electret charged to its maximum theoretical value.

  1. Stability of latent class segments over time

    DEFF Research Database (Denmark)

    Mueller, Simone

    2011-01-01

    Dynamic stability, as the degree to which identified segments at a given time remain unchanged over time in terms of number, size and profile, is a desirable segment property which has received limited attention so far. This study addresses the question to what degree latent classes identified from...

  2. Bayesian Multitask Learning with Latent Hierarchies

    CERN Document Server

    Daumé, Hal

    2009-01-01

    We learn multiple hypotheses for related tasks under a latent hierarchical relationship between tasks. We exploit the intuition that for domain adaptation, we wish to share classifier structure, but for multitask learning, we wish to share covariance structure. Our hierarchical model is seen to subsume several previously proposed multitask learning models and performs well on three distinct real-world data sets.

  3. Thermally Stable, Latent Olefin Metathesis Catalysts

    Science.gov (United States)

    Thomas, Renee M.; Fedorov, Alexey; Keitz, Benjamin K.

    2011-01-01

    Highly thermally stable N-aryl,N-alkyl N-heterocyclic carbene (NHC) ruthenium catalysts were designed and synthesized for latent olefin metathesis. These catalysts showed excellent latent behavior toward metathesis reactions, whereby the complexes were inactive at ambient temperature and initiated at elevated temperatures, a challenging property to achieve with second generation catalysts. A sterically hindered N-tert-butyl substituent on the NHC ligand of the ruthenium complex was found to induce latent behavior toward cross-metathesis reactions, and exchange of the chloride ligands for iodide ligands was necessary to attain latent behavior during ring-opening metathesis polymerization (ROMP). Iodide-based catalysts showed no reactivity toward ROMP of norbornene-derived monomers at 25 °C, and upon heating to 85 °C gave complete conversion of monomer to polymer in less than 2 hours. All of the complexes were very stable to air, moisture, and elevated temperatures up to at least 90 °C, and exhibited a long catalyst lifetime in solution at elevated temperatures. PMID:22282652

  4. On identifiability of certain latent class models.

    NARCIS (Netherlands)

    van Wieringen, W.N.

    2005-01-01

    Blischke [1962. Moment estimators for the parameters of a mixture of two binomial distributions. Ann. Math. Statist. 33, 444-454] studies a mixture of two binomials, a latent class model. In this article we generalize this model to a mixture of two products of binomials. We show when this generalize

  5. Latent Trait Estimation: Theory vs. Practice.

    Science.gov (United States)

    Kolakowski, Donald

    Empirical results are presented as regards the implementation of a latent-trait psychometric model by means of conditional maximum likelihood estimation. Items are scored polychotomously into varying numbers of nominal categories and the test and item characteristic curves and information functions are examined. It is concluded that scoring items…

  6. CICATRIZATION OF WOUNDS : XI. LATENT PERIOD.

    Science.gov (United States)

    Carrel, A; du Noüy, P L

    1921-09-30

    1. The latent period of cicatrization varies generally from 5 to 7 days. 2. It stops abruptly and contraction starts with its maximum velocity. 3. The formula of du Noüy applies to the beginning of the contraction period as well as to the subsequent periods.

  7. Latent mnemonic strengths are latent: a comment on Mickes, Wixted, and Wais (2007).

    Science.gov (United States)

    Rouder, Jeffrey N; Pratte, Michael S; Morey, Richard D

    2010-06-01

    Mickes, Wixted, and Wais (2007) proposed a simple test of latent strength variability in recognition memory. They asked participants to rate their confidence using either a 20-point or a 99-point strength scale and plotted distributions of the resulting ratings. They found 25% more variability in ratings for studied than for new items, which they interpreted as providing evidence that latent mnemonic strength distributions are 25% more variable for studied than for new items. We show here that this conclusion is critically dependent on assumptions--so much so that these assumptions determine the conclusions. In fact, opposite conclusions, such that study does not affect the variability of latent strength, may be reached by making different but equally plausible assumptions. Because all measurements of mnemonic strength variability are critically dependent on untestable assumptions, all are arbitrary. Hence, there is no principled method for assessing the relative variability of latent mnemonic strength distributions.

  8. Generalized latent variable modeling multilevel, longitudinal, and structural equation models

    CERN Document Server

    Skrondal, Anders

    2004-01-01

    METHODOLOGY THE OMNI-PRESENCE OF LATENT VARIABLES Introduction 'True' variable measured with error Hypothetical constructs Unobserved heterogeneity Missing values and counterfactuals Latent responses Generating flexible distributions Combining information Summary MODELING DIFFERENT RESPONSE PROCESSES Introduction Generalized linear models Extensions of generalized linear models Latent response formulation Modeling durations or survival Summary and further reading CLASSICAL LATENT VARIABLE MODELS Introduction Multilevel regression models Factor models and item respons

  9. Efeito do nível de energia da dieta e da exposição prévia ao calor sobre a respiração mitocondrial do músculo cardíaco de frangos de corte

    OpenAIRE

    Marcos Macari; Renato Luís Furlan; José Roberto Guerreiro; Euclides Roberto Secato

    1999-01-01

    Este trabalho foi realizado com o objetivo de avaliar o efeito do nível de energia da dieta, da exposição prévia ao calor e do sexo de frangos de corte sobre a atividade respiratória das mitocôndrias do músculo cardíaco de fragos de corte. Foram usados frangos Hubbard, de ambos os sexos, alimentados com ração contendo 2900 ou 3200 kcal de EM/kg e criados em câmara climática. Os frangos foram estressados por calor (35ºC/4 h) no 1º, 21º e 42º dia de idade. A atividade respiratória das mitocôndr...

  10. Caloric Restriction Effect on Proinflammatory Cytokines, Growth Hormone, and Steroid Hormone Concentrations during Exercise in Judokas

    OpenAIRE

    2015-01-01

    The aim of this study was to evaluate the effect of caloric restriction on the immune and hormonal responses during exercise in judo athletes. In a randomised order, 11 male judokas (age: 20.45 ± 0.51; height: 1.71 ± 0.3 m; and body weight: 75.9 ± 3.1 kg) participate in this study during a period of weight maintenance (baseline) and after 7 days of caloric restriction (CR). All subjects performed the Special Judo Fitness Test (SJFT) during the two conditions. Values for nutrient intakes were ...

  11. Ten-Year Trends in Children’s Caloric-Beverage Consumption and Behavioral Intent

    OpenAIRE

    Carnot MJ; Sutliffe JT; Palmer. SE; Elliott E

    2015-01-01

    Soft drinks, fruit juice and milk are the most common caloric-beverages consumed by adolescents and teens. We report the ten-year trends in the percentage of daily calories consumed in the form of caloric-beverages from a broad sample of fifth-grade students in the United States. This is a major area of concern related to dietary quality and body weight amongst children. The study was conducted from 2001-2011 through the Healthy Hearts for Kids (HH4K) online instructional ...

  12. Changes of endolymphatic pressure in the semicircular canal of pigeon by caloric stimulation

    Science.gov (United States)

    Wada, Y.; Suzuki, H.; Watanabe, S.

    1994-08-01

    It gets into difficult to explain the mechanism of caloric nystagmus only by convection theory from results of microgravity experiments. One of the other theories is an occurrence of a relative volume change due to a temperature change. Since the volume change must lead to a pressure change after caloric stimulation, we tried to measure the ampulla pressure of the horizontal semicircular canal in pigeons (Columba livia) using an improved servo micropipette system. The main result was that the ampulla pressure increased by cooling and decreased by heating. The changes of the ampulla pressure depended on the temperature change but were not influenced by the pigeon's head position.

  13. Aprofitant cada engruna de calor : el Tub Verd de Mataró

    OpenAIRE

    Alerm, Llorenç

    2012-01-01

    La calor residual de diverses infraestructures mediambientals permet distribuir calor i fred al seu entorn urbà. Es tracta d’un aprofitament energètic que redueix contaminació, emissions de CO2 i importacions de combustible. Una estratègia que fa anys que funciona a diversos països del món: al centre i nord d’Europa fa temps que hi està força estesa, i més recentment ha arribat aquí, amb iniciatives com la del Tub Verd de Mataró.

  14. Second Law Violation By Magneto-Caloric Effect Adiabatic Phase Transition of Type I Superconductive Particles

    Directory of Open Access Journals (Sweden)

    Peter Keefe

    2004-03-01

    Full Text Available Abstract: The nature of the thermodynamic behavior of Type I superconductor particles, having a cross section less than the Ginzburg-Landau temperature dependent coherence length is discussed for magnetic field induced adiabatic phase transitions from the superconductive state to the normal state. Argument is advanced supporting the view that when the adiabatic magneto-caloric process is applied to particles, the phase transition is characterized by a decrease in entropy in violation of traditional formulations of the Second Law, evidenced by attainment of a final process temperature below that which would result from an adiabatic magneto-caloric process applied to bulk dimensioned specimens.

  15. Absence of rotation perception during warm water caloric irrigation in some seniors with postural instability

    Directory of Open Access Journals (Sweden)

    Elodie eChiarovano

    2016-01-01

    Full Text Available Falls in seniors are a major public health problem. Falls lead to fear of falling, reduced mobility and decreased quality of life. Vestibular dysfunction is one of the fall risk factors. The relationship between objective measures of vestibular responses and age has been studied. However, the effects of age on vestibular perception during caloric stimulation have not been studied.Twenty senior subjects were included in the study separated in two groups: 10 seniors reporting postural instability (PI and exhibiting absence of vestibular perception when they tested with caloric stimulation and 10 sex and age-matched seniors with no such problems (controls. We assessed vestibular perception on a binary rating scale during the warm irrigation of the caloric test. The function of the various vestibular receptors was assessed using video-head impulse test (vHIT, caloric tests, and cervical and ocular VEMPs. The Equitest was used to evaluate balance. No horizontal canal dysfunction assessed using both caloric test and vHIT was detected in either group. No significant difference was detected between PI and control groups for the peak SPV of caloric induced ocular nystagmus or for the HVOR gain. All of the controls perceived rotation when the maximal SPV during warm irrigation was equal to or greater than 15°/s. None of the subjects in the PI group perceived rotation even while the peak SPV exceeded 15°/s, providing objective evidence of normal peripheral horizontal canal function. All of the PI group had abnormal Equitest results, particularly in the two last conditions.These investigations show for the first time that vestibular perception can be absent during a caloric test despite normal horizontal canal function. We call this dissociation vestibular neglect. Patients with poor vestibular perception may not be aware of postural perturbations and so will not correct for them. Thus, falls in the elderly may result, amongst other factors, from a

  16. Modelamiento y simulación de tubo de calor de alta temperatura

    OpenAIRE

    Guerra del Río, César Fabián

    2013-01-01

    Resumen: La tecnología de tubos de calor de alta temperatura permite recuperar la energía residual de procesos industriales que día a día se ven obligados a comprometerse en la solución de importantes limitaciones como la contaminación de gases efluentes, perdida deliberada de energía a los alrededores, limitación en el espacio físico para mejorar el proceso y aumento indiscriminado de los costos de inversión. Sin embargo, los tubos de calor de alta temperatura, presentan limitaciones en su f...

  17. Modelamiento y simulación de un tubo de calor de alta temperatura

    OpenAIRE

    Guerra del Río, César Fabián

    2013-01-01

    Resumen: La tecnología de tubos de calor de alta temperatura permite recuperar la energía residual de procesos industriales que día a día se ven obligados a comprometerse en la solución de importantes limitaciones como la contaminación de gases efluentes, perdida deliberada de energía a los alrededores, limitación en el espacio físico para mejorar el proceso y aumento indiscriminado de los costos de inversión. Sin embargo, los tubos de calor de alta temperatura, presentan limitaciones en su f...

  18. Caloric Intake From Fast Food Among Children and Adolescents in the United States, 2011-2012.

    Science.gov (United States)

    Vikraman, Sundeep; Fryar, Cheryl D; Ogden, Cynthia L

    2015-09-01

    Consumption of fast food has been linked to weight gain in adults (1). Fast food has also been associated with higher caloric intake and poorer diet quality in children and adolescents (2). From 1994 through 2006, caloric intake from fast food increased from 10% to 13% among children aged 2-18 years (3). This report presents the most recent data on the percentage of calories consumed from fast food among U.S. children by sex, age group, race and Hispanic origin, poverty status, and weight status.

  19. Fingerprint Minutiae from Latent and Matching Tenprint Images

    Science.gov (United States)

    NIST Fingerprint Minutiae from Latent and Matching Tenprint Images (PC database for purchase)   NIST Special Database 27 contains latent fingerprints from crime scenes and their matching rolled fingerprint mates. This database can be used to develop and test new fingerprint algorithms, test commercial and research AFIS systems, train latent examiners, and promote the ANSI/NIST file format standard.

  20. Effect of Replacing Sugar with Non-Caloric Sweeteners in Beverages on the Reward Value after Repeated Exposure

    NARCIS (Netherlands)

    Griffioen-Roose, S.; Smeets, P.A.M.; Weijzen, P.L.G.; Rijn, van I.; Bosch, van den I.; Graaf, de C.

    2013-01-01

    Background: The reward value of food is partly dependent on learned associations. It is not yet known whether replacing sugar with non-caloric sweeteners in food is affecting long-term acceptance. Objective: To determine the effect of replacing sugar with non-caloric sweeteners in a nutrient-empty d

  1. Superação da dormência de sementes de mucuna-preta pela utilização de "calor seco"

    OpenAIRE

    WUTKE,E.B.; MAEDA, J.A.; Pio,R.M.

    1995-01-01

    Avaliou-se a germinação de sementes recém-colhidas de mucuna preta (Mucuna aterrima) após tratamento com "calor seco", em estufa elétrica com ventilação forçada, nas temperaturas de 35, 45 e 55°C, por períodos de exposição correspondentes a 0, 2, 4, 6, 8,16,24, 48, 72 e 96 horas. A temperatura de 55°C foi adequada para a superação da impermeabilidade do tegumento da semente, sendo mais efetivos os períodos de exposição entre 16 e 24 horas.

  2. Elaboração e aplicação de uma estratégia de ensino sobre os conceitos de calor e de temperatura

    OpenAIRE

    Rafael, Francisco Josélio

    2007-01-01

    Este trabalho investigou as concepções alternativas apresentadas por alunos do Ensino Médio, em relação aos conceitos de calor e de temperatura, objetivando a elaboração e aplicação de uma estratégia de ensino a partir do diagnóstico levantado das concepções presentes nos estudantes. A estratégia de ensino foi constituída por uma seqüência de atividades que envolvem História da Ciência e experimentos, inseridas num curso que teve como base a proposta do Grupo de Reelaboração do Ensino de Físi...

  3. Soldagem por Difusão de Aços Inoxidáveis para Fabricação de Trocadores de Calor Compactos

    Directory of Open Access Journals (Sweden)

    Marcus Vinícius Volponi Mortean

    2016-03-01

    Full Text Available Resumo A união de materiais diferentes ou componentes com geometrias complexas muitas vezes requer processos de uniões especiais, como por exemplo, uma fonte de energia de alta densidade como laser ou feixe de elétrons para soldagem por fusão ou mesmo um processo de soldagem no estado sólido. Em particular, este trabalho descreve os experimentos recentes da aplicação da soldagem por difusão no estado sólido (SDES para diferentes tipos de aços inoxidáveis: austenítico AISI 316L, duplex UNS 31803 e superduplex UNS 327250. A soldagem por difusão foi realizada sob alto vácuo a 1050 °C, durante 60 minutos, empregando uma pressão uniaxial de 18-35 MPa. A qualidade da união foi avaliada por microscopia óptica e testes mecânicos. Os resultados preliminares indicam a necessidade de otimização dos parâmetros de processo para os aços duplex e superduplex. Os resultados positivos alcançados no presente trabalho permitiram a fabricação de protótipos de trocadores de calor compacto em aço inoxidável, utilizando o novo método de fabricação, desenvolvido por LABTUCAL / UFSC, através do qual o processo de corte a jato de água é aplicado para confeccionar com precisão os canais do núcleo do permutador de calor.

  4. Noisy-OR Models with Latent Confounding

    CERN Document Server

    Hyttinen, Antti; Hoyer, Patrik O

    2012-01-01

    Given a set of experiments in which varying subsets of observed variables are subject to intervention, we consider the problem of identifiability of causal models exhibiting latent confounding. While identifiability is trivial when each experiment intervenes on a large number of variables, the situation is more complicated when only one or a few variables are subject to intervention per experiment. For linear causal models with latent variables Hyttinen et al. (2010) gave precise conditions for when such data are sufficient to identify the full model. While their result cannot be extended to discrete-valued variables with arbitrary cause-effect relationships, we show that a similar result can be obtained for the class of causal models whose conditional probability distributions are restricted to a `noisy-OR' parameterization. We further show that identification is preserved under an extension of the model that allows for negative influences, and present learning algorithms that we test for accuracy, scalabili...

  5. Biomedical Literature Exploration through Latent Semantics

    Directory of Open Access Journals (Sweden)

    Hugo ARAÚJO

    2013-08-01

    Full Text Available The fast increasing amount of articles published in the biomedical field is creating difficulties in the way this wealth of information can be efficiently exploited by researchers. As a way of overcoming these limitations and potentiating a more efficient use of the literature, we propose an approach for structuring the results of a literature search based on the latent semantic information extracted from a corpus. Moreover, we show how the results of the Latent Semantic Analysis method can be adapted so as to evidence differences between results of different searches. We also propose different visualization techniques that can be applied to explore these results. Used in combination, these techniques could empower users with tools for literature guided knowledge exploration and discovery.

  6. Blocking of potentiation of latent inhibition.

    Science.gov (United States)

    Hall, Geoffrey; Rodriguez, Gabriel

    2011-01-01

    We present a theory of latent inhibition based on the Pearce-Hall (Pearce & Hall, 1980) model for classical conditioning. Its central features are (1) that the associability of a stimulus declines as it comes to predict its consequences and (2) that nonreinforced exposure to a stimulus engages an associative learning process that makes the stimulus an accurate predictor of its consequences (in this case, the occurrence of no event). A formalization of this theory is shown to accommodate the finding that preexposure in compound with another cue can potentiate latent inhibition to the target cue. It further predicts that preexposure to the added cue will eliminate the potentiation effect. An experiment using rats and the flavor-aversion procedure confirmed this prediction.

  7. Resource availability hypothesis: Perceived financial and caloric status affect individuals' height preferences for potential partners.

    Science.gov (United States)

    Sun, Qingzhou; Lou, Liandi; Lu, Jingyi; Wang, Xiaoming; Zhong, Jun; Tan, Xuyun; Li, Yanxia; Liu, Yongfang

    2016-10-01

    Height is an important concern in human mate choices. Prior research indicates that people who live in areas with abundant resources differ from those who live in areas with scarce resources regarding height preferences. Based on a health-maximizing principle, we propose a resource availability account for such differences. Compared with women's height preferences, men's height preferences are hypothesized to be more dependent on either financial or caloric resource availability. Specifically, taller females would be more preferred by males who are poor in resources than those who are rich in resources. Results from three studies supported these hypotheses. In Study 1, men from remote areas of China who had lower family income preferred taller women more than those from eastern China who had higher family income. In Study 2, men who were financially dissatisfied preferred taller women more than those who were financially satisfied. In Study 3, men with low caloric status preferred taller women more than men with high caloric status. In addition, women's height preferences in Studies 1, 2 and 3 were less determined by resource availability. These findings suggest that height preferences are changeable, depending on financial or caloric status.

  8. Effects of Caloric Restriction on Cardiac Oxidative Stress and Mitochondrial Bioenergetics: Potential Role of Cardiac Sirtuins

    Directory of Open Access Journals (Sweden)

    Ken Shinmura

    2013-01-01

    Full Text Available The biology of aging has not been fully clarified, but the free radical theory of aging is one of the strongest aging theories proposed to date. The free radical theory has been expanded to the oxidative stress theory, in which mitochondria play a central role in the development of the aging process because of their critical roles in bioenergetics, oxidant production, and regulation of cell death. A decline in cardiac mitochondrial function associated with the accumulation of oxidative damage might be responsible, at least in part, for the decline in cardiac performance with age. In contrast, lifelong caloric restriction can attenuate functional decline with age, delay the onset of morbidity, and extend lifespan in various species. The effect of caloric restriction appears to be related to a reduction in cellular damage induced by reactive oxygen species. There is increasing evidence that sirtuins play an essential role in the reduction of mitochondrial oxidative stress during caloric restriction. We speculate that cardiac sirtuins attenuate the accumulation of oxidative damage associated with age by modifying specific mitochondrial proteins posttranscriptionally. Therefore, the distinct role of each sirtuin in the heart subjected to caloric restriction should be clarified to translate sirtuin biology into clinical practice.

  9. A critique of Sadi Carnot's work and a mathematical theory of the caloric

    CERN Document Server

    Dass, N D Hari

    2013-01-01

    In this work, Sadi Carnot;s fundamental work is critically examined, and contrasted with modern thermodynamics. A mathematical theory of his work is given on the basis of the observation that in caloric theory dQ is a perfect differential.

  10. Biochemical composition and caloric potential of zooplankton from Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Sreepada, R.A.; Rivonker, C.U.; Parulekar, A.H.

    .62, 4.95, 1.54, 0.43, 4.4 and 4.16 respectively on wet weight basis. A good correlation of caloric potential with protein and lipid indicated to a certain extent that protein and lipid act as metabolic reserves of the zooplankton in the area...

  11. SIRT2 deacetylates FOXO3a in response to oxidative stress and caloric restriction

    Science.gov (United States)

    The sirtuin family of nicotinamide adenine dinucleotide-dependent (NAD) deacetylases plays an important role in aging and metabolic regulation. In yeast, the Sir2 gene and its homolog Hst2 independently mediate the action of caloric restriction on lifespan extension. The mammalian Sir2 ortholog, SIR...

  12. Timing versus caloric goal in nutritional therapy for critically ill patients

    Directory of Open Access Journals (Sweden)

    Oellen Stuani Franzosi

    Full Text Available Introduction: Enteral nutrition is an important therapy for severely critically ill patients. The timing and amount of energy have been highly debated. Objective: The aim of the present study was to directly compare the timing and the caloric targets in critically ill patients. Methods: Retrospective cohort study conducted at a single center, comparing timing and caloric goal for critically ill patients. Patients were stratified according to the start of nutritional therapy (24, 48, or more than 48 h and the amount of energy delivered (target adequacy of previously calculated percentage in the first week. Statistical analysis was performed using parametric and non-parametric tests for independent samples and logistic regression. The results were expressed as mean ± standard deviation or incidence and percentage. Results and discussion: There were no differences in major clinical outcomes in relation to the achievement of percentage of caloric goal at the end of the first week of the study. The beginning of caloric intake on the first day of hospitalization was associated with reduced mortality in the intensive care unit, but not with hospital mortality. The strategy of an early and limited amount of calories seems to be associated with a better outcome. Prospective studies evaluating and comparing these strategies are recommended.

  13. Thermoregulatory, Cardiovascular, and Metabolic Responses to Mild Caloric Restriction in the Brown Norway Rat

    Science.gov (United States)

    Caloric restriction (CR) has been demonstrated to prolong the life span of a variety of species. CR-induced reduction in core temperature (Tc) is considered a key mechanism responsible for prolonging life span in rodents; however, little is known on the regulation of CR-induced h...

  14. Latent variables and route choice behavior

    DEFF Research Database (Denmark)

    Prato, Carlo Giacomo; Bekhor, Shlomo; Pronello, Cristina

    2012-01-01

    In the last decade, a broad array of disciplines has shown a general interest in enhancing discrete choice models by considering the incorporation of psychological factors affecting decision making. This paper provides insight into the comprehension of the determinants of route choice behavior by...... results illustrate that considering latent variables (i.e., memory, habit, familiarity, spatial ability, time saving skills) alongside traditional variables (e.g., travel time, distance, congestion level) enriches the comprehension of route choice behavior....

  15. Barcelona - Talent Latent 09 / Ahto Sooaru

    Index Scriptorium Estoniae

    Sooaru, Ahto

    2010-01-01

    Fotonäitusest "Talent Latent 09" Barcelonas Arts Santa Monica kunstikeskuses. Loetletud näitusel eksponeeritud fotode autorid. Pikemalt Rafael Milach'i (sünd. 1978), Lucia Ganieva, Javier Marquerie Thomas'i (sünd. 1986), Amaury da Cunha (sünd. 1976) töödest. Lühidalt ka teistest näitustest Arts Santa Monica kunstikeskuses

  16. New Treatment Regimen for Latent Tuberculosis Infection

    Centers for Disease Control (CDC) Podcasts

    2012-03-15

    In this podcast, Dr. Kenneth Castro, Director of the Division of Tuberculosis Elimination, discusses the December 9, 2011 CDC guidelines for the use of a new regimen for the treatment of persons with latent tuberculosis infection.  Created: 3/15/2012 by National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP).   Date Released: 3/15/2012.

  17. The latent class multitrait-multimethod model.

    Science.gov (United States)

    Oberski, Daniel L; Hagenaars, Jacques A P; Saris, Willem E

    2015-12-01

    A latent class multitrait-multimethod (MTMM) model is proposed to estimate random and systematic measurement error in categorical survey questions while making fewer assumptions than have been made so far in such evaluations, allowing for possible extreme response behavior and other nonmonotone effects. The method is a combination of the MTMM research design of Campbell and Fiske (1959), the basic response model for survey questions of Saris and Andrews (1991), and the latent class factor model of Vermunt and Magidson (2004, pp. 227-230). The latent class MTMM model thus combines an existing design, model, and method to allow for the estimation of the degree to and manner in which survey questions are affected by systematic measurement error. Starting from a general form of the response function for a survey question, we present the MTMM experimental approach to identification of the response function's parameters. A "trait-method biplot" is introduced as a means of interpreting the estimates of systematic measurement error, whereas the quality of the questions can be evaluated by item information curves and the item information function. An experiment from the European Social Survey is analyzed and the results are discussed, yielding valuable insights into the functioning of a set of example questions on the role of women in society in 2 countries.

  18. Factors associated with latent fingerprint exclusion determinations.

    Science.gov (United States)

    Ulery, Bradford T; Hicklin, R Austin; Roberts, Maria Antonia; Buscaglia, JoAnn

    2017-02-22

    Exclusion is the determination by a latent print examiner that two friction ridge impressions did not originate from the same source. The concept and terminology of exclusion vary among agencies. Much of the literature on latent print examination focuses on individualization, and much less attention has been paid to exclusion. This experimental study assesses the associations between a variety of factors and exclusion determinations. Although erroneous exclusions are more likely to occur on some images and for some examiners, they were widely distributed among images and examiners. Measurable factors found to be associated with exclusion rates include the quality of the latent, value determinations, analysis minutia count, comparison difficulty, and the presence of cores or deltas. An understanding of these associations will help explain the circumstances under which errors are more likely to occur and when determinations are less likely to be reproduced by other examiners; the results should also lead to improved effectiveness and efficiency of training and casework quality assurance. This research is intended to assist examiners in improving the examination process and provide information to the broader community regarding the accuracy, reliability, and implications of exclusion decisions.

  19. Mixture latent autoregressive models for longitudinal data

    CERN Document Server

    Bartolucci, Francesco; Pennoni, Fulvia

    2011-01-01

    Many relevant statistical and econometric models for the analysis of longitudinal data include a latent process to account for the unobserved heterogeneity between subjects in a dynamic fashion. Such a process may be continuous (typically an AR(1)) or discrete (typically a Markov chain). In this paper, we propose a model for longitudinal data which is based on a mixture of AR(1) processes with different means and correlation coefficients, but with equal variances. This model belongs to the class of models based on a continuous latent process, and then it has a natural interpretation in many contexts of application, but it is more flexible than other models in this class, reaching a goodness-of-fit similar to that of a discrete latent process model, with a reduced number of parameters. We show how to perform maximum likelihood estimation of the proposed model by the joint use of an Expectation-Maximisation algorithm and a Newton-Raphson algorithm, implemented by means of recursions developed in the hidden Mark...

  20. First Versus Second Order Latent Growth Curve Models: Some Insights From Latent State-Trait Theory.

    Science.gov (United States)

    Geiser, Christian; Keller, Brian; Lockhart, Ginger

    2013-07-01

    First order latent growth curve models (FGMs) estimate change based on a single observed variable and are widely used in longitudinal research. Despite significant advantages, second order latent growth curve models (SGMs), which use multiple indicators, are rarely used in practice, and not all aspects of these models are widely understood. In this article, our goal is to contribute to a deeper understanding of theoretical and practical differences between FGMs and SGMs. We define the latent variables in FGMs and SGMs explicitly on the basis of latent state-trait (LST) theory and discuss insights that arise from this approach. We show that FGMs imply a strict trait-like conception of the construct under study, whereas SGMs allow for both trait and state components. Based on a simulation study and empirical applications to the CES-D depression scale (Radloff, 1977) we illustrate that, as an important practical consequence, FGMs yield biased reliability estimates whenever constructs contain state components, whereas reliability estimates based on SGMs were found to be accurate. Implications of the state-trait distinction for the measurement of change via latent growth curve models are discussed.

  1. Stem heat balance method to estimate transpiration of young orange and mango plants Balanço de calor caulinar para estimativa da transpiração de plantas jovens de laranja e manga

    Directory of Open Access Journals (Sweden)

    Lucas M. Vellame

    2010-01-01

    Full Text Available The present study had as its main objective the evaluation of the heat balance method in young orange and mango plants under protected environment. The work was carried out at Embrapa Cassava and Tropical Fruits, Cruz das Almas, BA. Later on, estimates of sap flow were conducted for two mango plants cultivated in pots of 15 and 50 L installed on weighting platforms of 45 and 140 kg; sap flow was determined in three orange plants, two of which were also installed on weighing platforms. The values of sap flow were compared to the transpiration measured by lysimeters at integrated intervals of 1, 2, 4 and 24 h. The heat balance method showed good precision for estimating daily transpiration (R² = 0.95 and R² = 0.90, accompaning the availability of energy in the system, underestimating on average 4.6% of the daily transpiration in orange plants and overestimating in about 0.3% the daily transpiration of mango plants under conditions of good water supply. The heat balance method underestimated by 16% the transpiration in orange under conditions of water deficit.Com o presente estudo se objetivou avaliar o método de balanço de calor em plantas jovens de laranja e manga em ambiente protegido. O trabalho foi conduzido na Embrapa Mandioca e Fruticultura, Cruz das Almas, BA. Realizaram-se estimativas de fluxo de seiva em duas plantas de manga plantadas em vasos de 15 e 50 L, instalados sobre plataformas de pesagem de 45 e 140 kg; posteriormente, o fluxo de seiva foi determinado em três plantas de laranja, duas também instaladas em lisímetros de pesagem. Os valores de fluxo de seiva obtidos foram comparados com a transpiração medida pelos lisímetros em intervalos de integração de 1, 2, 4 e 24 h. O método do balanço de calor mostrou-se preciso na estimativa da transpiração diária (R² = 0,95 e R² = 0,90, que acompanhou a disponibilidade de energia do sistema, subestimando em média, 4,6% a transpiração diária em plantas de laranja e

  2. Características do pelame de vacas Holandesas em ambiente tropical: um estudo genético e adaptativo Haircoat traits in Holstein cows in tropical environments: a genetic and adaptative study

    Directory of Open Access Journals (Sweden)

    Alex Sandro Campos Maia

    2003-08-01

    Full Text Available As características do pelame (espessura da capa, comprimento médio dos pêlos, número de pêlos por unidade de área, densidade de massa dos pêlos, ângulo de inclinação dos pêlos com respeito a superfície da epiderme e diâmetro médio do pêlos foram avaliadas em 973 vacas da raça Holandesa, entre novembro de 2000 e abril de 2001, numa área localizada 20cm abaixo da coluna vertebral, no centro do tronco, tanto nas malhas brancas como nas negras. As amostras de pêlos foram obtidas com um alicate comum adaptado. O método da Máxima Verossimilhança Restrita (REML foi usado para estimar os componentes de variância e covariância sob modelo animal, sendo empregado o sistema MTDFREML. Os resultados mostraram que as características do pelame preto são diferentes das do branco, quando os animais são criados em ambiente tropical. O pelame preto apresentou-se menos denso, com pêlos mais curtos e grossos devido à maior necessidade de perder calor, enquanto que, o pelame branco é mais denso e com pêlos mais compridos, oferecendo uma melhor proteção contra à radiação solar direta. A seleção de vacas predominantemente negras pode ser uma boa escolha para aumentar a resistência do gado Holandês às condições do ambiente tropical, principalmente à radiação solar, quando esses animais são criados a campo, devido a que a epiderme sob esse tipo de malhas é altamente pigmentada. Tal seleção pode ser facilmente realizada, considerando a alta herdabilidade (h²=0,75 para a proporção de malhas negras. Esta seleção deve ser realizada no sentido de um pelame menos denso, com pêlos curtos e grossos favorecendo as perdas de calor sensível e calor latente.The traits of the haircoat (haircoat thickness, average hair lenght with respect skin surface, number of hair per unit area, hair mass density, hair angle and average hair diameter were estimated in 973 Holstein cattle in the period between November 2000 and April of 2001

  3. Líneas de calor para convección natural en cavidades cerradas: Tres casos de estudio

    OpenAIRE

    J.G. Cervantes de Gortari; J.C. Torchia-Núñez; J.A. Serrano-Gutiérrez; A. Muñoz-Barrera; E. Guzmán-Vázquez; F. Gutiérrez-Coria; O. Chávez-López; I. Rosas-Yescas; E. Martínez-Galván

    2010-01-01

    Se presenta la técnica de visualización de líneas de calor para tres casos específicos de convección natural en cavidades cerradas. El objetivo es mostrar las ventajas de visualizar la transferencia de calor para un fluido en movimiento en lugar del uso de isotermas. Los tres casos de estudio se tomaron arbitraria mente por ser casos estudiados experimental y numéricamente, donde se conocen los campos de velocidad y temperatura, también por ser casos donde el régimen de trasferencia de calor ...

  4. Coeficientes de transferencia de calor y pérdida de eficiencia en intercambiadores de calor de placas durante el enfriamiento del licor amoniacal

    Directory of Open Access Journals (Sweden)

    Enrique Torres-Tamayo

    2011-10-01

    Full Text Available En la planta de Recuperación de Amoniaco de la empresa niquelera Ernesto Che Guevara la pérdida de eficiencia del proceso de enfriamiento del licor amoniacal, mediante el uso de intercambiadores de calor de placas, se asocia a la incorrecta estimación de los coeficientes de transferencia de calor y la acumulación de incrustaciones en la superficie de intercambio; lo anterior incrementa el consumo de agua, la energía disponible en el sistema y los costos de mantenimiento. Se realizó una investigación en un intercambiador de calor de placas, con el objetivo de determinar los coeficientes de transferencia y la influencia de las incrustaciones en la pérdida de eficiencia de la instalación. Mediante un procedimiento iterativo se determinó la ecuación del número de Nusselt y su dependencia con el Reynolds y Prandtl, para ello se utilizó un diseño experimental multifactorial y mediciones de los parámetros de trabajo de la instalación en función del tiempo. Los resultados predicen el conocimiento de los coeficientes para el cálculo del número de Nusselt, con los valores de Reynolds y Prandtl, para ambos fluidos (licor amoniacal y agua. Los valores de los coeficientes del licor son inferiores, ello se debe a la presencia de componentes gaseosos. La comparación con resultados de otros autores muestra correspondencia con los de Thonon. Se recomienda la limpieza y mantenimiento de la instalación en un período de 27 días debido a la reducción de la eficiencia térmica hasta valores inferiores al 70 %.

  5. Research on heat pumps in Mexico operating with geothermal energy and waste heat; Investigacion sobre bombas de calor en Mexico operando con energia geotermica y calor de desecho

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Gutierrez, A; Barragan-Reyes, R.M; Arellano-Gomez, V [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: aggarcia@iie.org.mx

    2008-01-15

    The Instituto de Investigaciones Electricas and the Comision Federal de Electricidad have done research and development (R&D) on heat pumps (HP) in past years. Tested systems include mechanical compression, absorption and heat-transformers. The main R&D aspects on HP are briefly described, and also a more detailed description about three of the main studies is presented: (a) a mechanical compression HP of the water-water type operated with low-pressure geothermal steam at the Los Azufres; Mich., geothermal field, and designed for purification of brine; (b) an absorption HP for cooling and refrigeration operating with ammonia-water and low-enthalpy geothermal energy, which was tested in the Los Azufres and Cerro Prieto, BC, geothermal fields; and (c) a heat-transformer by absorption-Absorption Heat Pump Type II-tested to assess the performance of several ternary solutions as work fluids. Plans exist to install and test a geothermal heat pump at Cerro Prieto or Mexicali, BC. [Spanish] El Instituto de Investigaciones Electricas y la Comision Federal de Electricidad han realizado trabajo de investigacion y desarrollo (I&D) sobre bombas de calor (BC) en el pasado. Los sistemas probados incluyen compresion mecanica, absorcion y transformadores termicos. Este trabajo describe brevemente los principales aspectos de I&D sobre bombas de calor en forma general, y se da una descripcion mas detallada de tres de los principales estudios: (a) una BC por compresion mecanica tipo agua-agua disenada para purificacion de salmueras operando con vapor geotermico de baja presion en el campo geotermico de Los Azufres, Mich.; (b) una BC por absorcion para enfriamiento y refrigeracion operando con amoniaco-agua y energia geotermica de baja entalpia, la cual fue probada en los campos geotermicos de Los Azufres y Cerro Prieto, BC; y (c) un transformador termico por absorcion -llamado Bomba de Calor por Absorcion Tipo II--, el cual fue probado para evaluar el comportamiento de diversas

  6. Latent Viruses: A Space Travel Hazard??

    Science.gov (United States)

    Ling, P. D.; Peng, R. S.; Pierson, D.; Lednicky, J.; Butel, J. S.

    1999-01-01

    A major issue associated with long-duration space flight is the possibility of infectious disease causing an unacceptable medical risk to crew members. Our proposal is designed to gain information that addresses several issues outlined in the Immunology/Infectious disease critical path. The major hypothesis addressed is that space flight causes alterations in the immune system that may allow latent viruses which are endogenous in the human population to reactivate and shed to higher levels than normal which can affect the health of crew members during a long term space-flight mission. We will initially focus our studies on the human herpesviruses and human polyomaviruses which are important pathogens known to establish latent infections in the human population. Both primary infection and reactivation from latent infection with this group of viruses can cause a variety of illnesses that result in morbidity and occasionally mortality of infected individuals. Effective vaccines exist for only one of the eight known human herpesviruses and the vaccine itself can still reactivate from latent infection. Available antivirals are of limited use and are effective against only a few of the human herpesviruses. Although most individuals display little if any clinical consequences from latent infection, events which alter immune function such as immunosuppressive therapy following solid organ transplantation are known to increase the risk of developing complications as a result of latent virus reactivation. This proposal will measure both the frequency and magnitude of viral shedding and genome loads in the blood from humans participating in activities that serve as ground based models of space flight conditions. Our initial goal is to develop sensitive quantitative competitive PCR- based assays (QC-PCR) to detect the herpesvirus Epstein-Barr virus (EBV), and the polyomaviruses SV40, BKV, and JCV. Using these assays we will establish baseline patterns of viral genome load in

  7. Latent inhibition and autonomic responses: a psychophysiological approach.

    Science.gov (United States)

    Vaitl, D; Lipp, O V

    1997-10-01

    Latent inhibition, retarded learning after preexposure to the to-be-conditioned stimulus, has been implied as a tool for the investigation of attentional deficits in schizophrenia and related disorders. The present paper reviews research that used Pavlovian conditioning as indexed by autonomic responses (electrodermal, vasomotor, cardiac) to investigate latent inhibition in adult humans. Latent inhibition has been demonstrated repeatedly in healthy subjects in absence of a masking task that is required in other latent inhibition paradigms. Moreover, latent inhibition of Pavlovian conditioning is stimulus-specific and increases with an increased number of preexposure trials which mirrors results from research in animals. A reduction of latent inhibition has been shown in healthy subjects who score high on questionnaire measures of psychosis proneness and in unmedicated schizophrenic patients. The latter result was obtained in a within-subject paradigm that holds promise for research with patient samples.

  8. Using existing questionnaires in latent class analysis

    DEFF Research Database (Denmark)

    Nielsen, Anne Molgaard; Vach, Werner; Kent, Peter;

    2016-01-01

    BACKGROUND: Latent class analysis (LCA) is increasingly being used in health research, but optimal approaches to handling complex clinical data are unclear. One issue is that commonly used questionnaires are multidimensional, but expressed as summary scores. Using the example of low back pain (LBP...... classified into four health domains (psychology, pain, activity, and participation) using the World Health Organization's International Classification of Functioning, Disability, and Health framework. LCA was performed within each health domain using the strategies of summary-score and single-item analyses...

  9. Functional networks underlying latent inhibition learning in the mouse brain

    OpenAIRE

    Puga, Frank; Barrett, Douglas W.; Bastida, Christel C.; Gonzalez-Lima, F.

    2007-01-01

    The present study reports the first comprehensive map of brain networks underlying latent inhibition learning and the first application of structural equation modeling to cytochrome oxidase data. In latent inhibition, repeated exposure to a stimulus results in a latent form of learning that inhibits subsequent associations with that stimulus. As neuronal energy demand to form learned associations changes, so does the induction of the respiratory enzyme cytochrome oxidase. Therefore, cytochrom...

  10. Protection from Latent Inhibition Provided by a Conditioned Inhibitor

    OpenAIRE

    McConnell, Bridget L.; Wheeler, Daniel S.; Urcelay, Gonzalo P; Miller, Ralph R.

    2009-01-01

    Two conditioned suppression experiments with rats investigated the influence on latent inhibition of compounding a Pavlovian conditioned inhibitor with the target cue during preexposure treatment. Results were compared to subjects that received conventional latent inhibition training, no preexposure, or preexposure to the target cue in compound with a neutral stimulus. In Experiment 1, greater attenuation of the latent inhibition effect was observed in subjects that received target preexposur...

  11. Latent mnemonic strengths are latent : A comment on Mickes, Wixted, and Wais

    NARCIS (Netherlands)

    Rouder, J.N.; Pratte, M.S.; Morey, R.D.

    2010-01-01

    Mickes, Wixted, and Wais (2007) proposed a simple test of latent strength variability in recognition memory. They asked participants to rate their confidence using either a 20-point or a 99-point strength scale and plotted distributions of the resulting ratings. They found 25% more variability in ra

  12. Bayesian Analysis of Multivariate Latent Curve Models with Nonlinear Longitudinal Latent Effects

    Science.gov (United States)

    Song, Xin-Yuan; Lee, Sik-Yum; Hser, Yih-Ing

    2009-01-01

    In longitudinal studies, investigators often measure multiple variables at multiple time points and are interested in investigating individual differences in patterns of change on those variables. Furthermore, in behavioral, social, psychological, and medical research, investigators often deal with latent variables that cannot be observed directly…

  13. A solar air collector with integrated latent heat thermal storage

    OpenAIRE

    Klimes Lubomir; Mauder Tomas; Ostry Milan; Charvat Pavel

    2012-01-01

    Simulations of the behaviour of a solar air collector with integrated latent heat thermal storage were performed. The model of the collector was created with the use of coupling between TRNSYS 17 and MATLAB. Latent heat storage (Phase Change Material - PCM) was integrated with the solar absorber. The model of the latent heat storage absorber was created in MATLAB and the model of the solar air collector itself was created in TRNSYS with the use of TYPE 56. The model of the latent heat storage...

  14. Caloric restriction in lean and obese strains of laboratory rat: effects on body composition, metabolism, growth and overall health

    Data.gov (United States)

    U.S. Environmental Protection Agency — Data related to obese and lean strains of rat commonly used in the laboratory that are calorically restricted and its effects on physiologic parameters (Body...

  15. Non-caloric artificial sweeteners and the microbiome: findings and challenges.

    Science.gov (United States)

    Suez, Jotham; Korem, Tal; Zilberman-Schapira, Gili; Segal, Eran; Elinav, Eran

    2015-01-01

    Non-caloric artificial sweeteners (NAS) are common food supplements consumed by millions worldwide as means of combating weight gain and diabetes, by retaining sweet taste without increasing caloric intake. While they are considered safe, there is increasing controversy regarding their potential ability to promote metabolic derangements in some humans. We recently demonstrated that NAS consumption could induce glucose intolerance in mice and distinct human subsets, by functionally altering the gut microbiome. In this commentary, we discuss these findings in the context of previous and recent works demonstrating the effects of NAS on host health and the microbiome, and the challenges and open questions that need to be addressed in understanding the effects of NAS consumption on human health.

  16. Non-caloric artificial sweeteners and the microbiome: findings and challenges

    Science.gov (United States)

    Suez, Jotham; Korem, Tal; Zilberman-Schapira, Gili; Segal, Eran; Elinav, Eran

    2015-01-01

    Non-caloric artificial sweeteners (NAS) are common food supplements consumed by millions worldwide as means of combating weight gain and diabetes, by retaining sweet taste without increasing caloric intake. While they are considered safe, there is increasing controversy regarding their potential ability to promote metabolic derangements in some humans. We recently demonstrated that NAS consumption could induce glucose intolerance in mice and distinct human subsets, by functionally altering the gut microbiome. In this commentary, we discuss these findings in the context of previous and recent works demonstrating the effects of NAS on host health and the microbiome, and the challenges and open questions that need to be addressed in understanding the effects of NAS consumption on human health. PMID:25831243

  17. Caloric curve of 8 GeV/c negative pion and antiproton + Au reactions

    CERN Document Server

    Ruangma, A; Martin, E; Ramakrishnan, E; Rowland, D J; Veselsky, M; Winchester, E M; Yennello, S J; Beaulieu, L; Hsi, W C; Kwiatkowski, K K; Lefort, T; Viola, V E; Botvina, A; Korteling, R G; Pienkowski, L; Breuer, H; Gushue, S; Remsberg, L P

    2002-01-01

    The relationship between nuclear temperature and excitation energy of hot nuclei formed by 8 GeV/c negative pion and antiproton beams incident on 197Au has been investigated with the ISiS 4-pidetector array at the BNL AGS accelerator. The double-isotope-ratio technique was used to calculate the temperature of the hot system. The two thermometers used (p/d-3He/4He) and (d/t-3He/4He) are in agreement below E*/A ~ 7 MeV when corrected for secondary decay. Comparison of these caloric curves to those from other experiments shows some differences that may be attributable to instrumentation and analysis procedures. The caloric curves from this experiment are also compared with the predictions from the SMM multifragmentation model.

  18. Equipos de transferencia de calor: una guía de estudio

    OpenAIRE

    Carrero Mantilla, Javier Ignacio

    2008-01-01

    La transferencia de calor es una ciencia básica de la ingeniería, que se incluye en los planes de estudio en muchas de las ramas de la profesión: mecánica, química, de alimentos, entre otras. En general, es posible dividir el estudio de la transferencia de calor en dos partes: la primera comprende los principios básicos del transporte de energía y de materia, mientras que la segunda se dedica al diseño y a la evaluación de equipos. El libro está distribuido en seis capítulos y dos apéndice...

  19. Mechanism‐Based Modeling of Gastric Emptying Rate and Gallbladder Emptying in Response to Caloric Intake

    Science.gov (United States)

    Sonne, DP; Hansen, M; Bagger, JI; Lund, A; Rehfeld, JF; Alskär, O; Karlsson, MO; Vilsbøll, T; Knop, FK; Bergstrand, M

    2016-01-01

    Bile acids released postprandially modify the rate and extent of absorption of lipophilic compounds. The present study aimed to predict gastric emptying (GE) rate and gallbladder emptying (GBE) patterns in response to caloric intake. A mechanism‐based model for GE, cholecystokinin plasma concentrations, and GBE was developed on data from 33 patients with type 2 diabetes and 33 matched nondiabetic individuals who were administered various test drinks. A feedback action of the caloric content entering the proximal small intestine was identified for the rate of GE. The cholecystokinin concentrations were not predictive of GBE, and an alternative model linking the nutrients amount in the upper intestine to GBE was preferred. Relative to fats, the potency on GBE was 68% for proteins and 2.3% for carbohydrates. The model predictions were robust across a broad range of nutritional content and may potentially be used to predict postprandial changes in drug absorption. PMID:28028939

  20. (Magneto)caloric refrigeration: is there light at the end of the tunnel?

    Science.gov (United States)

    Pecharsky, Vitalij K; Cui, Jun; Johnson, Duane D

    2016-08-13

    Caloric cooling and heat pumping rely on reversible thermal effects triggered in solids by magnetic, electric or stress fields. In the recent past, there have been several successful demonstrations of using first-order phase transition materials in laboratory cooling devices based on both the giant magnetocaloric and elastocaloric effects. All such materials exhibit non-equilibrium behaviours when driven through phase transformations by corresponding fields. Common wisdom is that non-equilibrium states should be avoided; yet, as we show using a model material exhibiting a giant magnetocaloric effect, non-equilibrium phase-separated states offer a unique opportunity to achieve uncommonly large caloric effects by very small perturbations of the driving field(s).This article is part of the themed issue 'Taking the temperature of phase transitions in cool materials'.

  1. Mechanism-Based Modeling of Gastric Emptying Rate and Gallbladder Emptying in Response to Caloric Intake

    DEFF Research Database (Denmark)

    Guiastrennec, B; Sonne, D P; Hansen, M;

    2016-01-01

    concentrations were not predictive of GBE, and an alternative model linking the nutrients amount in the upper intestine to GBE was preferred. Relative to fats, the potency on GBE was 68% for proteins and 2.3% for carbohydrates. The model predictions were robust across a broad range of nutritional content and may......Bile acids released postprandially modify the rate and extent of absorption of lipophilic compounds. The present study aimed to predict gastric emptying (GE) rate and gallbladder emptying (GBE) patterns in response to caloric intake. A mechanism-based model for GE, cholecystokinin plasma...... concentrations, and GBE was developed on data from 33 patients with type 2 diabetes and 33 matched nondiabetic individuals who were administered various test drinks. A feedback action of the caloric content entering the proximal small intestine was identified for the rate of GE. The cholecystokinin...

  2. Desarrollos instrumentales en microcalorimetría de conducción de calor

    Directory of Open Access Journals (Sweden)

    Liliana Girlado G.

    2010-07-01

    Full Text Available Se presentan aspectos generales de la microcalorimetría de conducción de calor. Se describe el diseño y la operación de microcalorímetros de conducción de calor estático y de flujo construidos en este laboratorio, los cuales fueron calibrados eléctrica y químicamente. Estos equipos se emplean en la caracterización de sólidos porosos por la técnica de calorimetría de inmersión y en la determinación de entalpias de transferencia de solutos; su uso se ilustra con algunos resultados típicos. Se mencionan además otras aplicaciones que se dan actualmente a estos aparatos.

  3. Parental attachment insecurity predicts child and adult high-caloric food consumption.

    Science.gov (United States)

    Faber, Aida; Dubé, Laurette

    2015-05-01

    Eating habits are established early and are difficult to change once formed. This study investigated the role of caregiver-child attachment quality and its associations with high-caloric food consumption in a sample of middle socio-economic status children and adults, respectively. Survey data were collected from an online questionnaire administered separately to 213 (143 girls) children and 216 parents (adult sample; 180 women). Two studies showed that an insecure parental attachment, whether actual (Study 1; children) or recalled (Study 2; adults), significantly and positively predicted high-caloric food consumption in both samples. The present findings highlight the importance of parental attachment and its association with unhealthy eating patterns in children and adults.

  4. DISEÑO Y CONSTRUCCIÓN DE PROTOTIPO PARA MEDICIÓN DE FLUJO DE CALOR APLICANDO CALORIMETRÍA DIRECTA: SENSADO POR FLUJO DE CALOR

    Directory of Open Access Journals (Sweden)

    OSCAR CADENA

    2008-01-01

    Full Text Available El presente artículo describe el diseño de un prototipo inalámbrico para la medición de flujo de calor, que permita a futuro aplicar el método de calorimetría directa por gradiente de flujo de calor en el área de la electrónica médica. Esta técnica se desarrolla gracias al avance y creación de sensores que permiten medir este tipo de variables, y se postula como una alternativa a las formas de medición utilizadas actualmente, presentando mejoras en su desempeño y costo. Los resultados obtenidos luego de efectuar la calibración del equipo permiten inferir que la técnica propuesta se adapta de forma eficiente y puede utilizarse como un sustituto significativamente más ventajoso comparado con los métodos existentes en la actualidad y aplicados en el seguimiento metabólico de personas.

  5. Composição centesimal e valor calórico de alimentos de origem animal Proximate food composition and caloric value of foods from animal origen

    Directory of Open Access Journals (Sweden)

    Elizabeth A.F.S TORRES

    2000-08-01

    Full Text Available Dados sobre composição de alimentos são importantes para inúmeras atividades, porém são escassos ou inexistentes em nosso país. O presente trabalho teve como objetivo determinar o valor calórico dos alimentos de origem animal comumente usados na dieta: carne, leite e ovos a fim de compará-los com os dados das tabelas de composição centesimal mais utilizadas por profissionais da área. Observou-se que de um modo geral, ocorrem variações entre os valores das tabelas consultadas e os analisados, sendo estes menores para ovos, seguidos de laticínios, carnes suínas, carnes bovinas e aves. Salientamos portanto, a importãncia de obtenção dados sobre a composição de alimentos condizentes com diferenças regionais do Brasil, visto que a maioria das tabelas disponíveis são compilações de dados internacionais.Proximate food composition data are very important to any professionals of food science and human nutrition area. In Brazil they are rare or do not exist. The food composition of items, of animal origin, usually consumed in the diet: meat, milk e eggs, were analyzed in order to determine their caloric value. After that they were compared with the data in the Tables of Food Composition (TFC commonly used to our professionals. It was observed that there are smaller differences in the values obtained for eggs, than milk, pork, beef, chicken. Although significant difference was not detected between determined caloric values and the ones from TFC, these report should be considered to professionals that use the TFC.

  6. Fertilidade de gemas em videiras: fisiologia e fatores envolvidos

    OpenAIRE

    2006-01-01

    O presente trabalho teve como objetivo descrever a fisiologia da formação das gemas férteis em videiras, assim como discutir os fatores envolvidos neste processo. A formação das inflorescências em videiras se inicia no ciclo anterior à sua antese, durante o desenvolvimento das gemas latentes, sendo concluída na brotação destas gemas no ciclo seguinte. Didaticamente, este processo pode ser dividido em três principais etapas: 1) Formação do primórdio indiferenciado; 2) Diferenciação em primórdi...

  7. Temas de Física para Ingeniería: Temperatura y propagación del calor

    OpenAIRE

    Beléndez Vázquez, Augusto

    1992-01-01

    Acústica, fluidos y termodinámica: "Temperatura y propagación del calor". Introducción. Descripciones macroscópica y microscópica de un sistema. Equilibrio térmico y principio cero de la termodinámica. Termómetros y escala de temperaturas del gas ideal. Dilatación térmica. Propagación del calor.

  8. Caloric Vestibular Stimulation as a Treatment for Conversion Disorder: A Case Report and Medical Hypothesis

    OpenAIRE

    Michael eNoll-Hussong; Sabrina eHolzapfel; Dan ePokorny; Simone D Herberger

    2014-01-01

    Conversion disorder is a medical condition in which a person has paralysis, blindness, or other neurological symptoms that cannot be clearly explained physiologically. To date, there is neither specific nor conclusive treatment. In this paper, we draw together a number of disparate pieces of knowledge to propose a novel intervention to provide transient alleviation for this condition. As caloric vestibular stimulation (CVS) has been demonstrated to modulate transiently a variety of cognitive ...

  9. Heat pump for purification of geothermal brines; Bomba de calor para purificacion de salmuera geotermica

    Energy Technology Data Exchange (ETDEWEB)

    Santoyo-Gutierrez, S; Barragan-Reyes, R.M; Holland, F.A [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: rmb@iie.org.mx

    2007-01-15

    Integrated use of geothermal resources is one of the most important goals for the future. Presently geothermal heat pumps offer two benefits: using heat from residual brines and converting these brines into very pure water. Designs and descriptions are presented of an experimental system to purify geothermal brines integrated to an adsorption heat-pump. The system was constructed and tested in the IIE (Institute for Electrical Research) facilities. During the experimental stage, pure water was obtained. Maximum capacity for pure water was 4.3 kg per hour, presenting an Actual Coefficient of Performance (COP)A of 1.4. The results are encouraging to project units at an industrial level for operating with geothermal and/or solar heat. [Spanish] El aprovechamiento integral de los recursos geotermicos en todas sus formas es una de las metas importantes a lograr en los proximos anos. Hoy en dia, el uso de las bombas de calor en la geotermia ofrece un doble beneficio: aprovechan el calor de los fluidos de desecho y tienen la capacidad de transformar la salmuera geotermica en agua de alta pureza. Se presenta el diseno y descripcion de un sistema experimental para purificacion de salmuera geotermica integrado a una bomba de calor por absorcion, el cual fue construido y probado en el Instituto de Investigaciones Electricas. En toda la etapa de experimentacion se obtuvo agua pura. La capacidad maxima alcanzada de produccion de agua pura de este sistema fue de 4.3 kg por hora, mostrando un rendimiento en terminos del Coeficiente Real de Rendimiento (COP)A de 1.4. Estos resultados se consideran alentadores para la proyeccion de unidades a escala industrial que puedan ser operadas con calor geotermico y/o solar.

  10. Dimensionamiento de intercambiadores de calor de coraza y tubos, con ayuda de computador

    OpenAIRE

    Gabriel Eduardo Rocha Camino; Rangel Jara, Hermes A.

    2011-01-01

    En este trabajo se plantea el problema de optimizar el diseño de un intercambiador de calor del tipo coraza y tubos, y se propone un método para resolverlo, con base en la técnica del "estudio paramétrico de la respuesta". Además, se muestra la necesidad de utilizar el computador como herramienta para Implementar dicho método, y se describe un programa escrito con tal fin.

  11. Vestibular Function Tests for Vestibular Migraine: Clinical Implication of Video Head Impulse and Caloric Tests.

    Science.gov (United States)

    Kang, Woo Seok; Lee, Sang Hun; Yang, Chan Joo; Ahn, Joong Ho; Chung, Jong Woo; Park, Hong Ju

    2016-01-01

    Vestibular migraine (VM) is one of the most common causes of episodic vertigo. We reviewed the results of multiple vestibular function tests in a cohort of VM patients who were diagnosed with VM according to the diagnostic criteria of the Barany Society and the International Headache Society and assessed the efficacy of each for predicting the prognosis in VM patients. A retrospective chart analysis was performed on 81 VM patients at a tertiary care center from June 2014 to July 2015. Patients were assessed by the video head impulse test (vHIT), caloric test, vestibular-evoked myogenic potentials (VEMPs), and sensory organization test (SOT) at the initial visit and then evaluated for symptomatic improvement after 6 months. Complete response (CR) was defined as no need for continued medication, partial response (PR) as improved symptoms but need for continued medication, and no response (NR) as no symptomatic improvement and requiring increased dosage or change in medications. At the initial evaluation, 9 of 81 patients (11%) exhibited abnormal vHIT results, 14 of 73 (19%) exhibited abnormal caloric test results, 25 of 65 (38%) exhibited abnormal SOT results, 8 of 75 (11%) exhibited abnormal cervical VEMP results, and 20 of 75 (27%) exhibited abnormal ocular VEMP results. Six months later, 63 of 81 patients (78%) no longer required medication (CR), while 18 (22%) still required medication, including 7 PR and 11 NR patients. Abnormal vHIT gain and abnormal caloric results were significantly related to the necessity for continued medication at 6-month follow-up (OR = 5.67 and 4.36, respectively). Abnormal vHIT and caloric test results revealed semicircular canal dysfunction in VM patients and predicted prolonged preventive medication requirement. These results suggest that peripheral vestibular abnormalities are closely related to the development of vertigo in VM patients.

  12. Vestibular function tests for vestibular migraine: clinical implication of video head impulse and caloric tests

    Directory of Open Access Journals (Sweden)

    Woo Seok Kang

    2016-09-01

    Full Text Available Vestibular migraine (VM is one of the most common causes of episodic vertigo. We reviewed the results of multiple vestibular function tests in a cohort of VM patients who were diagnosed with VM according to the diagnostic criteria of the Barany Society and the International Headache Society and assessed the efficacy of each for predicting the prognosis in VM patients. A retrospective chart analysis was performed on 81 VM patients at a tertiary care center from June 2014 to July 2015. Patients were assessed by the video head impulse test (vHIT, caloric test, vestibular-evoked myogenic potentials (VEMP, and sensory organization test (SOT at the initial visit and then evaluated for symptomatic improvement after 6 months. Complete response (CR was defined as no need for continued medication, partial response (PR as improved symptoms but need for continued medication, and no response (NR as no symptomatic improvement and requiring increased dosage or change in medications. At the initial evaluation, 9 of 81 patients (11% exhibited abnormal vHIT results, 14 of 73 (19% exhibited abnormal caloric test results, 25 of 65 (38% exhibited abnormal SOT results, 8 of 75 (11% exhibited abnormal cervical VEMP results, and 20 of 75 (27% exhibited abnormal ocular VEMP results. Six months later, 63 of 81 patients (78% no longer required medication (CR, while 18 (22% still required medication, including 7 PR and 11 NR patients. Abnormal vHIT gain and abnormal caloric results were significantly related to the necessity for continued medication at 6-month follow-up (OR = 5.67 and 4.36, respectively. Abnormal vHIT and caloric test results revealed semicircular canal dysfunction in VM patients and predicted prolonged preventive medication requirement. These results suggest that peripheral vestibular abnormalities are closely related to the development of vertigo in VM patients.

  13. Vestibular Function Tests for Vestibular Migraine: Clinical Implication of Video Head Impulse and Caloric Tests

    Science.gov (United States)

    Kang, Woo Seok; Lee, Sang Hun; Yang, Chan Joo; Ahn, Joong Ho; Chung, Jong Woo; Park, Hong Ju

    2016-01-01

    Vestibular migraine (VM) is one of the most common causes of episodic vertigo. We reviewed the results of multiple vestibular function tests in a cohort of VM patients who were diagnosed with VM according to the diagnostic criteria of the Barany Society and the International Headache Society and assessed the efficacy of each for predicting the prognosis in VM patients. A retrospective chart analysis was performed on 81 VM patients at a tertiary care center from June 2014 to July 2015. Patients were assessed by the video head impulse test (vHIT), caloric test, vestibular-evoked myogenic potentials (VEMPs), and sensory organization test (SOT) at the initial visit and then evaluated for symptomatic improvement after 6 months. Complete response (CR) was defined as no need for continued medication, partial response (PR) as improved symptoms but need for continued medication, and no response (NR) as no symptomatic improvement and requiring increased dosage or change in medications. At the initial evaluation, 9 of 81 patients (11%) exhibited abnormal vHIT results, 14 of 73 (19%) exhibited abnormal caloric test results, 25 of 65 (38%) exhibited abnormal SOT results, 8 of 75 (11%) exhibited abnormal cervical VEMP results, and 20 of 75 (27%) exhibited abnormal ocular VEMP results. Six months later, 63 of 81 patients (78%) no longer required medication (CR), while 18 (22%) still required medication, including 7 PR and 11 NR patients. Abnormal vHIT gain and abnormal caloric results were significantly related to the necessity for continued medication at 6-month follow-up (OR = 5.67 and 4.36, respectively). Abnormal vHIT and caloric test results revealed semicircular canal dysfunction in VM patients and predicted prolonged preventive medication requirement. These results suggest that peripheral vestibular abnormalities are closely related to the development of vertigo in VM patients.

  14. Caloric restriction and intermittent fasting: Two potential diets for successful brain aging

    OpenAIRE

    Martin, Bronwen; Mark P. Mattson; Maudsley, Stuart

    2006-01-01

    The vulnerability of the nervous system to advancing age is all too often manifest in neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. In this review article we describe evidence suggesting that two dietary interventions, caloric restriction (CR) and intermittent fasting (IF), can prolong the health-span of the nervous system by impinging upon fundamental metabolic and cellular signaling pathways that regulate life-span. CR and IF affect energy and oxygen radical meta...

  15. Effects of caloric deprivation and satiety on sensitivity of the gustatory system

    Directory of Open Access Journals (Sweden)

    Zverev Yuriy P

    2004-02-01

    Full Text Available Abstract Background Sensitivity of the gustatory system could be modulated by a number of short-term and long-term factors such as body mass, gender, age, local and systemic diseases and pathological processes, excessive alcohol drinking, drug dependence, smoking, composition of oral fluid, state of oral hygiene, consumption of some foods among many others. A few studies have demonstrated the effects of hunger and caloric satiety on sensitivity of the gustatory system in obese humans and animals. The aim of the present study was to assess the effects of short-term caloric deprivation and satiety on recognition taste thresholds of healthy, non-smoking, non-drinking, non-obese young male subjects. The two-alternative forced-choice technique was used to measure taste threshold. Results Recognition thresholds for sucrose and salt were significantly lower during fasting state than after a meal (t = 2.23, P Conclusions Short-term caloric deprivation in our study model was associated with increased taste sensitivity to sweet and salty substances compared to satiated state while taste sensitivity to bitter substances was not affected by the conditions of measurements. Selective modulation of sensitivity of the gustatory system might reflect the different biological importance of salty, sweet and bitter qualities of taste.

  16. Importance of silvopastoral systems on caloric stress reduction in tropical livestock productions

    Directory of Open Access Journals (Sweden)

    Alexander Navas Panadero

    2010-06-01

    Full Text Available Livestock systems in Colombia have been developed taking concepts and technologies from the green revolution, where gramineous monocrop is privileged over arboreal cover in grazing lands. This model has not taken into account the climatic conditions of the different tropical ecosystems, in which variables as temperature, relative humidity and evaporation can limit the animal´s productive and reproductive efficiency, besides being a risk factor for illness occurrence in the herd. Bos Taurus and Bos Indicus breeds show termoneutral ranges where its genetic potential can be express. However, out of this comfort area animals can enter in caloric stress which in consequence reduces its performance and sometimes can end up causing death. Silvopastoral systems comprise several functions; it contributes to lessen caloric stress since temperature under the tree canopy can reach between 2 and 9°C lower in comparison to open pastures. Differences in temperature reduction have been found among silvopastoral systems and species, being the tree group arrangements and the species with high density canopy, those with superior effect. Interactions among components should be analyzed in order to design systems that incorporate enough arboreal cover to achieve caloric stress reductions, but without affecting forage production in pastures. Silvopastoral systems contribute to improve animal welfare.

  17. Fluid-structural dynamics of ground-based and microgravity caloric tests

    Science.gov (United States)

    Kassemi, M.; Oas, J. G.; Deserranno, Dimitri

    2005-01-01

    Microgravity caloric tests aboard the 1983 SpaceLab1 mission produced nystagmus results with an intensity comparable to those elicited during post- and pre- flight tests, thus contradicting the basic premise of Barany's convection hypothesis for caloric stimulation. In this work, we present a dynamic fluid structural analysis of the caloric stimulation of the lateral semicircular canal based on two simultaneous driving forces for the endolymphatic flow: natural convection driven by the temperature-dependent density variation in the bulk fluid and expansive convection caused by direct volumetric displacement of the endolymph during the thermal irrigation. Direct numerical simulations indicate that on earth, the natural convection mechanism is dominant. But in the microgravity environment of orbiting spacecraft, where buoyancy effects are mitigated, expansive convection becomes the sole mechanism for producing cupular displacement. A series of transient 1 g and microgravity case studies are presented to delineate the differences between the dynamics of the 1 g and microgravity endolymphatic flows. The impact of these different flow dynamics on the endolymph-cupula fluid-structural interactions is also analyzed based on the time evolutions of cupular displacement and velocity and the transcupular pressure differences.

  18. Cervical vestibular evoked myogenic potentials and caloric test results in individuals with auditory neuropathy spectrum disorders.

    Science.gov (United States)

    Sujeet, Kumar Sinha; Niraj, Kumar Singh; Animesh, Barman; Rajeshwari, G; Sharanya, R

    2014-01-01

    Auditory neuropathy spectrum disorder is a type of hearing loss where outer hair cell function are normal (as evidenced by the preservation of OAEs and cochlear microphonics), whereas auditory nerve functions are abnormal (as evidenced by abnormal auditory brainstem evoked potentials beginning with wave I of the ABR) and acoustic reflexes to ipsilateral and contralateral tones are absent. It is likely that in cases with auditory neuropathy spectrum disorder not only the cochlear nerve, but also the vestibular nerves might get involved. The present study was conducted with an aim of finding out the inferior and superior vestibular nerve involvement through cervical vestibular evoked myogenic potentials and Caloric test results respectively in individuals with Auditory Neuropathy Spectrum Disorders. Total 26 participants who fulfilled the criteria of auditory neuropathy spectrum disorder participated for the study. Vestibular evoked myogenic potentials results showed absence of responses from most of the subjects also caloric responses showed bilateral hypofunctional responses in most of the participants, which is suggestive of involvement of both the inferior as well as superior vestibular nerve in individuals with auditory neuropathy spectrum disorders. Additionally there was no association between the pattern and degree of hearing loss to caloric test results and vestibular evoked myogenic potentials results findings.

  19. Subjective Visual Vertical during Caloric Stimulation in Healthy Subjects: Implications to Research and Neurorehabilitation

    Directory of Open Access Journals (Sweden)

    Martha Funabashi

    2015-01-01

    Full Text Available Background. The subjective visual vertical (SVV is a perception often impaired in patients with neurologic disorders and is considered a sensitive tool to detect otolithic dysfunctions. However, it remains unclear whether the semicircular canals (SCCs are also involved in the visual vertical perception. Objective. The aim of this study was to analyze the influence of horizontal SCCs on SVV by caloric stimulation in healthy subjects. Methods. SVV was performed before and during the ice-cold caloric stimulation (4°C, right ear in 30 healthy subjects. Results. The mean SVV tilts before and during the caloric stimulation were 0.31° ± 0.39 and −0.28° ± 0.40, respectively. There was no significant difference between the mean SVV tilts before and during stimulation p=0.113. Conclusion. These results suggest that horizontal SCCs do not influence SVV. Therefore, investigations and rehabilitation approaches for SVV misperceptions should be focused on otolithic and cognitive strategies.

  20. Chemical Profiles and Identification of Key Compound Caffeine in Marine-Derived Traditional Chinese Medicine <em>Ostreae em>concha>

    Directory of Open Access Journals (Sweden)

    Hong-Bing Liu

    2012-05-01

    Full Text Available To compare the chemical differences between the medicinal and<em> em>cultured oyster shells, their chemical profiles were investigated. Using the ultra performance liquid chromatography-electron spraying ionization-mass spectrometry (UPLC-ESI-MS, combined with principal component analysis (PCA and orthogonal projection to latent structures discriminant analysis (OPLS-DA, the discrimination of the chemical characteristics among the medicinal and cultured oyster shells was established. Moreover, the chemometric analysis revealed some potential key compounds. After a large-scale extraction and isolation, one target key compound was unambiguously identified as caffeine (1 based on extensive spectroscopic data analysis (1D and 2D NMR, MS, and UV and comparison with literature data.

  1. Feeding preference of adult females of ribbonfish Trichiurus lepturus through prey proximate-composition and caloric values

    Directory of Open Access Journals (Sweden)

    Vanessa Trindade Bittar

    Full Text Available In the present study we analysed the proximate-composition and caloric values of the preferred prey consumed by ribbonfish, Trichiurus lepturus L. 1758 (adult females, that are distributed in the inner continental shelf from northern Rio de Janeiro State, southeastern Brazil (~22ºS, assessing the potential of nutritional and energetic approach as a tool to understand the feeding selective pattern of this marine top carnivore. The preferred prey of this predator composed of fish co-specifics, Pellona harroweri, Chirocentrodon bleekerianus, Lycengraulis grossidens, Peprilus paru, squid Doryteuthis plei, and shrimp Xiphopenaeus kroyeri were collected from 2007 to 2010 for proximate-composition (water, protein, lipid, ash, and carbohydrate and caloric value analyses. The correspondence analysis showed that protein is the main component in the prey species (61.32% of variance explained, standing out from the other nutrients. Lipid has the highest percentage related to L. grossidens, ash to X. kroyeri and carbohydrate to D. plei. The strong correlations between protein and caloric value (positive and lipid and caloric value (negative indicated that T. lepturus is attending its energy demand through the prey protein content. This work elucidated the feeding preference of adult females of T. lepturus in relation to nutritional and caloric content of their preferred prey. The species showed food selectivity to prey that provide more energy per ingested biomass, so that the feeding events can maximize the predator's caloric gain, which is obtained by a protein-based diet.

  2. Economic management of vertigo/dizziness disease in a county hospital: video-head-impulse test vs. caloric irrigation.

    Science.gov (United States)

    Rambold, Holger A

    2015-10-01

    The video-head-impulse test (vHIT) is an important test for examining unilateral vestibular hypofunction. Alternatively, one can test for vestibular hypofunction with the caloric irrigation test. Various studies have shown that both tests may not always identify vestibular hypofunction; instead, the results of the tests might be contradictory. This retrospective study reproduces those finding in a much larger group of patients at a county hospital. 1063 patients were examined with the vHIT and bithermal caloric irrigation on the same day and analyzed with respect to side differences. Of those patients 13.3% had pathological vHIT and a caloric irrigation test, 4.6% a pathological vHIT only and 24.1% a pathologic caloric test only. As both tests might be necessary, we calculated the optimal sequence of the two examinations based on savings in time for the different disease groups. Especially in vestibular failure using the vHIT first and only applying the caloric irrigation in case of an unremarkable vHIT saves time and optimizes the diagnostic work up. In contrast, in Menière's disease and vestibular migraine testing caloric irrigation first might be more efficient.

  3. Saccharin and aspartame, compared with sucrose, induce greater weight gain in adult Wistar rats, at similar total caloric intake levels.

    Science.gov (United States)

    Feijó, Fernanda de Matos; Ballard, Cíntia Reis; Foletto, Kelly Carraro; Batista, Bruna Aparecida Melo; Neves, Alice Magagnin; Ribeiro, Maria Flávia Marques; Bertoluci, Marcello Casaccia

    2013-01-01

    It has been suggested that the use of nonnutritive sweeteners (NNSs) can lead to weight gain, but evidence regarding their real effect in body weight and satiety is still inconclusive. Using a rat model, the present study compares the effect of saccharin and aspartame to sucrose in body weight gain and in caloric intake. Twenty-nine male Wistar rats received plain yogurt sweetened with 20% sucrose, 0.3% sodium saccharin or 0.4% aspartame, in addition to chow and water ad libitum, while physical activity was restrained. Measurements of cumulative body weight gain, total caloric intake, caloric intake of chow and caloric intake of sweetened yogurt were performed weekly for 12 weeks. Results showed that addition of either saccharin or aspartame to yogurt resulted in increased weight gain compared to addition of sucrose, however total caloric intake was similar among groups. In conclusion, greater weight gain was promoted by the use of saccharin or aspartame, compared with sucrose, and this weight gain was unrelated to caloric intake. We speculate that a decrease in energy expenditure or increase in fluid retention might be involved.

  4. APLICAÇÃO DO MÉTODO DE BALANÇO DE CALOR NA DETERMINAÇÃO DA TRANSPIRAÇÃO DE MUDAS DE LIMOEIRO

    Directory of Open Access Journals (Sweden)

    J.E. TREJO-CHANDIA

    1997-09-01

    Full Text Available O método de balanço de calor é usado para monitorar fluxo de seiva em plantas de diversas espécies. Neste trabalho, estudou-se o desempenho e aplicabilidade do método, em mudas de limoeiro com diâmetros em torno de 18 mm. Os sensores foram avaliados em plantas envasadas, em casa de vegetação, sob condições naturais de temperatura e radiação solar. O desempenho do método foi avaliado comparando-se o fluxo de massa computado e as medidas gravimétricas de perda de massa, fazendo-se depois, análise de regressão. Os resultados indicam que os sensores tiveram uma precisão de 8% na escala horária e 11% na escala diária. A constante de tempo foi de 12 minutos, o que é um indicativo de que o método é adequado para medir fluxo de seiva em mudas de citros com boa precisão, e suficientemente apropriado para ser usado em aplicações agronômicas e fisiológicas.The heat balance method is widely used to measure sap flow of different plant species. This work focused on the performance and applicability of the method, using 2-year old lemon plants, with 18 mm in diameter, the sensors were evaluated on potted-plants in a greenhouse under natural temperature and solar radiation conditions. The method performance was tested by comparing the computed mass flow with weight losses. A regression equation was used to analyse the data collected. The results showed that sensor precision reached 8% in the hourly scale and 11% in the daily scale. The time constant of 12 minutes indicated that the method was accurate to measure sap flow with good precision. Also we concluded that the method is adequate for agronomic and physiological use.

  5. Caloric beverages were major sources of energy among children and adults in Mexico, 1999-2012.

    Science.gov (United States)

    Stern, Dalia; Piernas, Carmen; Barquera, Simon; Rivera, Juan A; Popkin, Barry M

    2014-06-01

    Mexico, with 1 of the highest obesity prevalences in the world, instituted a 10% excise tax for any sugar-sweetened beverage (SSB) starting on 1 January 2014. Understanding the recent patterns and trends in beverage intake and sales in Mexico provides both background and baseline data for the importance of SSBs and other beverages in the Mexican diet. We analyzed a single 24-h dietary recall from 2 nationally representative surveys: the Mexican Nutrition Survey 1999 (n = 6049) and the National Health and Nutrition Survey 2012 (n = 10,343). To describe trends and patterns in beverages, we calculated the volume and energy intake per capita and per consumer and the proportion of consumers of each beverage group in each survey. A commercial sales dataset was used to describe beverage sales trends from 1999 to 2012. From 1999 to 2012, total daily energy from beverages increased among children aged 5-11 y (+45.3 kcal), females aged 12-19 y (+57.3 kcal), and adult females aged 20-49 y (+96.4 kcal) (P agua fresca (fruit water made in stalls or at home, usually with added sugars), and fruit drinks among children aged 5-11 y and females aged 12-19 y and caloric coffee/tea, soda, and agua fresca among adult females aged 20-49 y. In 2012, beverages represented 17.5% (325 kcal) and 19.0% (382 kcal) of the total daily energy intake per capita in children aged 1-19 y and adults aged ≥20 y, respectively. In 2012, flavored milk beverages, caloric soda, and high-fat milk were the top 3 major contributors to total daily energy intake per capita in all children aged 1-19 y. Caloric soda, caloric coffee/tea, and agua fresca were the top 3 major energy contributors in adults aged ≥20 y. From 1999 to 2012, sales of soda, fruit-flavored drinks, and flavored waters increased. In conclusion, consumption of several beverages with added sugars increased among children and adult females in Mexico. Because caloric soda is currently 1 of the top beverages consumed, a 10% tax on SSBs might

  6. Higher-Order Item Response Models for Hierarchical Latent Traits

    Science.gov (United States)

    Huang, Hung-Yu; Wang, Wen-Chung; Chen, Po-Hsi; Su, Chi-Ming

    2013-01-01

    Many latent traits in the human sciences have a hierarchical structure. This study aimed to develop a new class of higher order item response theory models for hierarchical latent traits that are flexible in accommodating both dichotomous and polytomous items, to estimate both item and person parameters jointly, to allow users to specify…

  7. A Simplified Estimation of Latent State--Trait Parameters

    Science.gov (United States)

    Hagemann, Dirk; Meyerhoff, David

    2008-01-01

    The latent state-trait (LST) theory is an extension of the classical test theory that allows one to decompose a test score into a true trait, a true state residual, and an error component. For practical applications, the variances of these latent variables may be estimated with standard methods of structural equation modeling (SEM). These…

  8. Nonlinear Latent Curve Models for Multivariate Longitudinal Data

    Science.gov (United States)

    Blozis, Shelley A.; Conger, Katherine J.; Harring, Jeffrey R.

    2007-01-01

    Latent curve models have become a useful approach to analyzing longitudinal data, due in part to their allowance of and emphasis on individual differences in features that describe change. Common applications of latent curve models in developmental studies rely on polynomial functions, such as linear or quadratic functions. Although useful for…

  9. A Review of the Latent and Manifest Benefits (LAMB) Scale

    Science.gov (United States)

    Muller, Juanita; Waters, Lea

    2012-01-01

    The latent and manifest benefits (LAMB) scale (Muller, Creed, Waters & Machin, 2005) was designed to measure the latent and manifest benefits of employment and provide a single scale to test Jahoda's (1981) and Fryer's (1986) theories of unemployment. Since its publication in 2005 there have been 13 studies that have used the scale with 5692…

  10. PROC LCA: A SAS Procedure for Latent Class Analysis

    Science.gov (United States)

    Lanza, Stephanie T.; Collins, Linda M.; Lemmon, David R.; Schafer, Joseph L.

    2007-01-01

    Latent class analysis (LCA) is a statistical method used to identify a set of discrete, mutually exclusive latent classes of individuals based on their responses to a set of observed categorical variables. In multiple-group LCA, both the measurement part and structural part of the model can vary across groups, and measurement invariance across…

  11. Latent lifestyle and mode choice decisions when travelling short distances

    DEFF Research Database (Denmark)

    Prato, Carlo Giacomo; Halldórsdóttir, Katrín; Nielsen, Otto Anker

    2016-01-01

    of a representative sample of the Danish population in the Copenhagen Region were analysed, and more specifically a latent class choice model was estimated to uncover latent lifestyle groups and choice specific travel behaviour. Results show that four lifestyle groups are identified in the population: car oriented...

  12. Incorporating direct marketing activity into latent attrition models

    NARCIS (Netherlands)

    Schweidel, David A.; Knox, George

    2013-01-01

    When defection is unobserved, latent attrition models provide useful insights about customer behavior and accurate forecasts of customer value. Yet extant models ignore direct marketing efforts. Response models incorporate the effects of direct marketing, but because they ignore latent attrition, th

  13. Gene Variants Associated with Antisocial Behaviour: A Latent Variable Approach

    Science.gov (United States)

    Bentley, Mary Jane; Lin, Haiqun; Fernandez, Thomas V.; Lee, Maria; Yrigollen, Carolyn M.; Pakstis, Andrew J.; Katsovich, Liliya; Olds, David L.; Grigorenko, Elena L.; Leckman, James F.

    2013-01-01

    Objective: The aim of this study was to determine if a latent variable approach might be useful in identifying shared variance across genetic risk alleles that is associated with antisocial behaviour at age 15 years. Methods: Using a conventional latent variable approach, we derived an antisocial phenotype in 328 adolescents utilizing data from a…

  14. A Latent Class Approach to Estimating Test-Score Reliability

    Science.gov (United States)

    van der Ark, L. Andries; van der Palm, Daniel W.; Sijtsma, Klaas

    2011-01-01

    This study presents a general framework for single-administration reliability methods, such as Cronbach's alpha, Guttman's lambda-2, and method MS. This general framework was used to derive a new approach to estimating test-score reliability by means of the unrestricted latent class model. This new approach is the latent class reliability…

  15. A LATENT TRAIT MODEL FOR DICHOTOMOUS CHOICE DATA

    NARCIS (Netherlands)

    HOIJTINK, H

    1990-01-01

    The PARELLA model is a probabilistic parallelogram model that can be used for the measurement of latent attitudes or latent preferences. The data analyzed are the dichotomous responses of persons to stimuli, with a one (zero) indicating agreement (disagreement) with the content of the stimulus. The

  16. Latent Images, Blind Comments on Photography

    Directory of Open Access Journals (Sweden)

    Jenny Feray

    2013-12-01

    Full Text Available Photographs, or images as the final result of a process, merely mark out the moment when the eye is helplessly limited to what it sees. Thus, what escapes the eye in the physical sense, i.e. what the eye will never see, is what occurs before the product- image, within the act itself. The latent image, the desire-image, unfolds throughout the duration of the photographic act. When the picture is ‘taken’, then the desire subsides until the next desire for another image arises. Based on the photographic experiment by Jerry Chan, member of a group of blind people, this article aims at rethinking the photographic act as the real- life experience of an impression process, leading the blind apprentice photographer to experience sightedness within his very flesh.  

  17. Endogenous Opioid-Masked Latent Pain Sensitization

    DEFF Research Database (Denmark)

    Pereira, Manuel P; Donahue, Renee R; Dahl, Jørgen B

    2015-01-01

    naloxone dose (0.021 mg/kg). However, while LS was consistently demonstrated in 21/24 mice, LS was only seen in 4/12 subjects. This difference is likely due to selection bias since the C57BL/6 mouse strain exhibits markedly enhanced pain sensitivity in assays of acute thermal nociception. Future......UNLABELLED: Following the resolution of a severe inflammatory injury in rodents, administration of mu-opioid receptor inverse agonists leads to reinstatement of pain hypersensitivity. The mechanisms underlying this form of latent pain sensitization (LS) likely contribute to the development...... of chronic pain, but LS has not yet been demonstrated in humans. Using a C57BL/6 mouse model of cutaneous mild heat injury (MHI) we demonstrated a dose-dependent reinstatement of pain sensitization, assessed as primary (P

  18. Unsupervised Feature Selection for Latent Dirichlet Allocation

    Institute of Scientific and Technical Information of China (English)

    Xu Weiran; Du Gang; Chen Guang; Guo Jun; Yang Jie

    2011-01-01

    As a generative model Latent Dirichlet Allocation Model,which lacks optimization of topics' discrimination capability focuses on how to generate data,This paper aims to improve the discrimination capability through unsupervised feature selection.Theoretical analysis shows that the discrimination capability of a topic is limited by the discrimination capability of its representative words.The discrimination capability of a word is approximated by the Information Gain of the word for topics,which is used to distinguish between “general word” and “special word” in LDA topics.Therefore,we add a constraint to the LDA objective function to let the “general words” only happen in “general topics”other than “special topics”.Then a heuristic algorithm is presented to get the solution.Experiments show that this method can not only improve the information gain of topics,but also make the topics easier to understand by human.

  19. Pretreatment of Latent Prints for Laser Development.

    Science.gov (United States)

    Menzel, E R

    1989-06-01

    The pretreatment procedures for laser detection of latent fingerprints is reviewed. The general features of laser detection and the operational aspects of the examination of physical evidence for laser fingerprint detection are enumerated in the initial sections. The literature review is divided into various pretreatment approaches. Cited studies prior to 1981 are primarily concerned with the demonstration of the viability of laser fingerprint detection, whereas work post-1981 addresses issues of compatibility with the traditional methods of fingerprint development, examination of difficult surfaces, and the routine implementation of laser detection by law enforcement agencies. Related topics of research, review articles, conference reports, case examinations, the research support climate, and future trends are also briefly addressed.

  20. A latent classification of male batterers.

    Science.gov (United States)

    Mauricio, Anne M; Lopez, Frederick G

    2009-01-01

    Regression latent class analysis was used to identify batterer subgroups with distinct violence patterns and to examine associations between class membership and adult attachment orientations as well as antisocial and borderline personality disorders. Results supported three batterer subgroups, with classes varying on frequency and severity of violence. The high-level violence class represented 40% of batterers, and both anxious and avoidant adult attachment orientations as well as borderline personality characteristics predicted membership in this class. The moderate-level violence class represented 35% of the batterers, and adult anxious attachment orientation was associated with membership in this class. The low-level violence class represented 25% of the sample and reported significantly less violence than other classes. Neither adult attachment orientations nor personality disorders predicted membership in this class.

  1. Targeting latent TGFβ release in muscular dystrophy.

    Science.gov (United States)

    Ceco, Ermelinda; Bogdanovich, Sasha; Gardner, Brandon; Miller, Tamari; DeJesus, Adam; Earley, Judy U; Hadhazy, Michele; Smith, Lucas R; Barton, Elisabeth R; Molkentin, Jeffery D; McNally, Elizabeth M

    2014-10-22

    Latent transforming growth factor-β (TGFβ) binding proteins (LTBPs) bind to inactive TGFβ in the extracellular matrix. In mice, muscular dystrophy symptoms are intensified by a genetic polymorphism that changes the hinge region of LTBP, leading to increased proteolytic susceptibility and TGFβ release. We have found that the hinge region of human LTBP4 was also readily proteolysed and that proteolysis could be blocked by an antibody to the hinge region. Transgenic mice were generated to carry a bacterial artificial chromosome encoding the human LTBP4 gene. These transgenic mice displayed larger myofibers, increased damage after muscle injury, and enhanced TGFβ signaling. In the mdx mouse model of Duchenne muscular dystrophy, the human LTBP4 transgene exacerbated muscular dystrophy symptoms and resulted in weaker muscles with an increased inflammatory infiltrate and greater LTBP4 cleavage in vivo. Blocking LTBP4 cleavage may be a therapeutic strategy to reduce TGFβ release and activity and decrease inflammation and muscle damage in muscular dystrophy.

  2. Latent factors and route choice behaviour

    DEFF Research Database (Denmark)

    Prato, Carlo Giacomo

    . A reliable dataset was prepared through measures of internal consistency and sampling adequacy, and data were analyzed with a proper application of factor analysis to the route choice context. For the dataset obtained from the survey, six latent constructs affecting driver behaviour were extracted and scores...... by proposing a methodology for collecting and analyzing behavioural indicators and modelling route choices of individuals driving habitually from home to their workplace. A web-based survey was designed to collect attitudinal data and observed route choices among faculty and staff members of Turin Polytechnic...... on each factor for each survey participant were calculated. Path generation algorithms were examined with respect to observed behaviour, through a measure of reproduction with deterministic techniques of the routes indicated in the answers to the survey. Results presented evidence that the majority...

  3. Latent Herpes Viral Reactivation in Astronauts

    Science.gov (United States)

    Pierson, D. L.; Mehta, S. K.; Stowe, R.

    2008-01-01

    Latent viruses are ubiquitous and reactivate during stressful periods with and without symptoms. Latent herpes virus reactivation is used as a tool to predict changes in the immune status in astronauts and to evaluate associated health risks. Methods: Viral DNA was detected by real time polymerase chain reaction in saliva and urine from astronauts before, during and after short and long-duration space flights. Results and Discussion: EpsteinBarr virus (EBV), cytomegalovirus (CMV), and varicella zoster virus (VZV) reactivated, and viral DNA was shed in saliva (EBV and VZV) or urine (CMV). EBV levels in saliva during flight were 10fold higher than baseline levels. Elevations in EBV specific CD8+ T-cells, viral antibody titers, and specific cytokines were consistent with viral reactivation. Intracellular levels of cytokines were reduced in EBVspecific Tcells. CMV, rarely present in urine of healthy individuals, was shed in urine of 27% of astronauts during all phases of spaceflight. VZV, not found in saliva of asymptomatic individuals, was found in saliva of 50% of astronauts during spaceflight and 35 days after flight. VZV recovered from astronaut saliva was found to be live, infectious virus. DNA sequencing demonstrated that the VZV recovered from astronauts was from the common European strain of VZV. Elevation of stress hormones accompanied viral reactivation indicating involvement of the hypothalmic-pituitary-adrenal and sympathetic adrenal-medullary axes in the mechanism of viral reactivation in astronauts. A study of 53 shingles patients found that all shingles patients shed VZV DNA in their saliva and the VZV levels correlated with the severity of the disease. Lower VZV levels in shingles patients were similar to those observed in astronauts. We proposed a rapid, simple, and cost-effective assay to detect VZV in saliva of patients with suspected shingles. Early detection of VZV infection allows early medical intervention.

  4. Latent Virus Reactivation in Space Shuttle Astronauts

    Science.gov (United States)

    Mehta, S. K.; Crucian, B. E.; Stowe, R. P.; Sams, C.; Castro, V. A.; Pierson, D. L.

    2011-01-01

    Latent virus reactivation was measured in 17 astronauts (16 male and 1 female) before, during, and after short-duration Space Shuttle missions. Blood, urine, and saliva samples were collected 2-4 months before launch, 10 days before launch (L-10), 2-3 hours after landing (R+0), 3 days after landing (R+14), and 120 days after landing (R+120). Epstein-Barr virus (EBV) DNA was measured in these samples by quantitative polymerase chain reaction. Varicella-zoster virus (VZV) DNA was measured in the 381 saliva samples and cytomegalovirus (CMV) DNA in the 66 urine samples collected from these subjects. Fourteen astronauts shed EBV DNA in 21% of their saliva samples before, during, and after flight, and 7 astronauts shed VZV in 7.4% of their samples during and after flight. It was interesting that shedding of both EBV and VZV increased during the flight phase relative to before or after flight. In the case of CMV, 32% of urine samples from 8 subjects contained DNA of this virus. In normal healthy control subjects, EBV shedding was found in 3% and VZV and CMV were found in less than 1% of the samples. The circadian rhythm of salivary cortisol measured before, during, and after space flight did not show any significant difference between flight phases. These data show that increased reactivation of latent herpes viruses may be associated with decreased immune system function, which has been reported in earlier studies as well as in these same subjects (data not reported here).

  5. Data on the interexaminer variation of minutia markup on latent fingerprints

    Directory of Open Access Journals (Sweden)

    Bradford T. Ulery

    2016-09-01

    Full Text Available The data in this article supports the research paper entitled “Interexaminer variation of minutia markup on latent fingerprints” [1]. The data in this article describes the variability in minutia markup during both analysis of the latents and comparison between latents and exemplars. The data was collected in the “White Box Latent Print Examiner Study,” in which each of 170 volunteer latent print examiners provided detailed markup documenting their examinations of latent-exemplar pairs of prints randomly assigned from a pool of 320 pairs. Each examiner examined 22 latent-exemplar pairs; an average of 12 examiners marked each latent.

  6. Tropical Gravity Wave Momentum Fluxes and Latent Heating Distributions

    Science.gov (United States)

    Geller, Marvin A.; Zhou, Tiehan; Love, Peter T.

    2015-01-01

    Recent satellite determinations of global distributions of absolute gravity wave (GW) momentum fluxes in the lower stratosphere show maxima over the summer subtropical continents and little evidence of GW momentum fluxes associated with the intertropical convergence zone (ITCZ). This seems to be at odds with parameterizations forGWmomentum fluxes, where the source is a function of latent heating rates, which are largest in the region of the ITCZ in terms of monthly averages. The authors have examined global distributions of atmospheric latent heating, cloud-top-pressure altitudes, and lower-stratosphere absolute GW momentum fluxes and have found that monthly averages of the lower-stratosphere GW momentum fluxes more closely resemble the monthly mean cloud-top altitudes rather than the monthly mean rates of latent heating. These regions of highest cloud-top altitudes occur when rates of latent heating are largest on the time scale of cloud growth. This, plus previously published studies, suggests that convective sources for stratospheric GW momentum fluxes, being a function of the rate of latent heating, will require either a climate model to correctly model this rate of latent heating or some ad hoc adjustments to account for shortcomings in a climate model's land-sea differences in convective latent heating.

  7. In vivo disruption of latent HSV by designer endonuclease therapy.

    Science.gov (United States)

    Aubert, Martine; Madden, Emily A; Loprieno, Michelle; DeSilva Feelixge, Harshana S; Stensland, Laurence; Huang, Meei-Li; Greninger, Alexander L; Roychoudhury, Pavitra; Niyonzima, Nixon; Nguyen, Thuy; Magaret, Amalia; Galleto, Roman; Stone, Daniel; Jerome, Keith R

    2016-09-08

    A large portion of the global population carries latent herpes simplex virus (HSV), which can periodically reactivate, resulting in asymptomatic shedding or formation of ulcerative lesions. Current anti-HSV drugs do not eliminate latent virus from sensory neurons where HSV resides, and therefore do not eliminate the risk of transmission or recurrent disease. Here, we report the ability of HSV-specific endonucleases to induce mutations of essential HSV genes both in cultured neurons and in latently infected mice. In neurons, viral genomes are susceptible to endonuclease-mediated mutagenesis, regardless of the time of treatment after HSV infection, suggesting that both HSV lytic and latent forms can be targeted. Mutagenesis frequency after endonuclease exposure can be increased nearly 2-fold by treatment with a histone deacetylase (HDAC) inhibitor. Using a mouse model of latent HSV infection, we demonstrate that a targeted endonuclease can be delivered to viral latency sites via an adeno-associated virus (AAV) vector, where it is able to induce mutation of latent HSV genomes. These data provide the first proof-of-principle to our knowledge for the use of a targeted endonuclease as an antiviral agent to treat an established latent viral infection in vivo.

  8. Olas de calor e influencia urbana en Madrid y su área metropolitana

    Directory of Open Access Journals (Sweden)

    Fernández García, F.

    2008-12-01

    Full Text Available The frequency and duration of the warmest temperature episodes, a common phenomenon under the continental Mediterranean conditions of the Spanish Southern Meseta, has increased in the Madrid area since the 80´s, although their magnitude remains unchanged. The effect of the urban environment on those extreme events has exacerbated the heat load due to the persistence of the high temperatures along the night time hours. Nevertheless, the diversity of the urban morphology introduces a spatial variability on the strength of this nocturnal heat load, aggravating it in the densely urbanized areas and mitigating it in the vicinities of the green areas.

    La frecuencia y duración de los episodios cálidos extremos, un fenómeno habitual en el clima mediterráneo continental de la Meseta Meridional, ha aumentado en el área de Madrid desde los años noventa, aunque su magnitud permanece constante. En el interior de la aglomeración urbana, el efecto general de la ciudad sobre estos eventos climáticos extremos ha supuesto una exacerbación del calor, no tanto por un aumento de la temperatura máxima, como por una persistencia del calor en las horas nocturnas. No obstante, la diversidad de la morfología urbana introduce variaciones espaciales en la intensidad de este calor nocturno, agravando sus efectos en las áreas densamente urbanizadas y mitigándolos en las proximidades de las áreas verdes.

  9. Lost in processing? Perceived healthfulness, taste and caloric content of whole and processed organic food.

    Science.gov (United States)

    Prada, Marília; Garrido, Margarida V; Rodrigues, David

    2017-03-23

    The "organic" claim explicitly informs consumers about the food production method. Yet, based on this claim, people often infer unrelated food attributes. The current research examined whether the perceived advantage of organic over conventional food generalizes across different organic food types. Compared to whole organic foods, processed organic foods are less available, familiar and prototypical of the organic food category. In two studies (combined N = 258) we investigated how both organic foods types were perceived in healthfulness, taste and caloric content when compared to their conventional alternatives. Participants evaluated images of both whole (e.g., lettuce) and processed organic food exemplars (e.g., pizza), and reported general evaluations of these food types. The association of these evaluations with individual difference variables - self-reported knowledge and consumption of organic food, and environmental concerns - was also examined. Results showed that organically produced whole foods were perceived as more healthful, tastier and less caloric than those produced conventionally, thus replicating the well-established halo effect of the organic claim in food evaluation. The organic advantage was more pronounced among individuals who reported being more knowledgeable about organic food, consumed it more frequently, and were more environmentally concerned. The advantage of the organic claim for processed foods was less clear. Overall, processed organic (vs. conventional) foods were perceived as tastier, more healthful (Study 1) or equally healthful (Study 2), but also as more caloric. We argue that the features of processed food may modulate the impact of the organic claim, and outline possible research directions to test this assumption. Uncovering the specific conditions in which food claims bias consumer's perceptions and behavior may have important implications for marketing, health and public-policy related fields.

  10. Effects of emodin on treating murine nonalcoholic fatty liver induced by high caloric laboratory chaw

    Institute of Scientific and Technical Information of China (English)

    Hui Dong; Fu-Er Lu; Zhi-Qiang Gao; Li-Jun Xu; Kai-Fu Wang; Xin Zou

    2005-01-01

    AIM: To investigate the effects of emodin on the treatment of non-alcoholic fatty liver in rats induced by high caloric laboratory chaw.METHODS: Non-alcoholic fatty liver model was successfully established by feeding with high caloric laboratory chaw for 12 wk. Then the model rats were randomly divided into 3 groups, namely model control group, emodin group and dietary treatment group. The rats in emodin group in othergroups were given distilled water of the same volume. The rats in model control group were fed with high caloric laboratory chaw while animals in other groups were fed with normal diet. Four weeks later, liver index (liver/body weight ratio), serum activities of liver-associated enzymes, blood lipid, fasting blood glucose, fasting plasma insulin, HOMA insulin resistance index (HOMA-IR), hepatic triglyceride content and histology features of all groups were assayed. The expression of hepatic peroxisomal proliferator activated receptor (PPAR) gamma was determined by RT-PCR.RESULTS: The body weight, liver index, serum activities of alanine aminotransferase (ALT), blood lipid, hepatic triglyceride content of model control group were significantly elevated, with moderate to severe hepatocyte steatosis.The expression of hepatic PPAR gamma mRNA was obviously reduced in model control group. Compared with model control group, the body weight, liver index, serum activities of ALT, blood lipids and hepatic triglyceride of emodin group significantly decreased and hepatic histology display was also greatly improved. Meanwhile, the expression of hepatic PPAR gamma mRNA was elevated.However, high serum activities of ALT and hyperlipidemia were persisted in dietary treatment group although liver index was decreased and liver histology was somewhat improved.CONCLUSION: It is suggested that emodin might be effective in the treatment of non-alcoholic fatty liver in rats. Its therapeutic mechanism could be associated with increasing the expression of hepatic PPAR gamma mRNA.

  11. Caloric restriction in C57BL/6J mice mimics therapeutic fasting in humans

    Directory of Open Access Journals (Sweden)

    Denny Christine A

    2006-05-01

    Full Text Available Abstract Background Caloric restriction (CR has long been recognized as a dietary therapy that improves health and increases longevity. Little is known about the persistent effects of CR on plasma biomarkers (glucose, ketone bodies, and lipids following re-feeding in mice. It is also unclear how these biomarker changes in calorically restricted mice relate to those observed previously in calorically restricted humans. Results Three groups of individually housed adult female C57BL/6J (B6 mice (n = 4/group were fed a standard rodent chow diet either: (1 unrestricted (UR; (2 restricted for three weeks to reduce body weight by approximately 15–20% (R; or (3 restricted for three weeks and then re-fed unrestricted (ad libitum for an additional three weeks (R-RF. Body weight and food intake were measured throughout the study, while plasma lipids and levels of glucose and ketone bodies (β-hydroxybutyrate were measured at the termination of the study. Plasma glucose, phosphatidylcholine, cholesterol, and triglycerides were significantly lower in the R mice than in the UR mice. In contrast, plasma fatty acids and β-hydroxybutyrate were significantly higher in the R mice than in the UR mice. CR had no effect on plasma phosphatidylinositol levels. While body weight and plasma lipids of the R-RF mice returned to unrestricted levels upon re-feeding, food intake and glucose levels remained significantly lower than those prior to the initiation of CR. Conclusion CR establishes a new homeostatic state in B6 mice that persists for at least three weeks following ad libitum re-feeding. Moreover, the plasma biomarker changes observed in B6 mice during CR mimic those reported in humans on very low calorie diets or during therapeutic fasting.

  12. Evaluation of a direct contact heat exchanger; Evaluacion de un intercambiador de calor de contacto directo

    Energy Technology Data Exchange (ETDEWEB)

    Siqueiros, J.; Bonilla, O. [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1997-12-31

    In this paper the application areas of the direct contact heat exchangers is discussed, as well as its main characteristics. A description is made of the experimental equipment designed and built at pilot scale including the instrumentation employed. The methodology employed as well as the analysis and the discussion of the results are also presented. [Espanol] Se mencionan las areas de aplicacion de los intercambiadores de calor de contacto directo, asi como sus caracteristicas principales. Se describe el equipo experimental a nivel piloto disenado y construido incluyendo la instrumentacion utilizada. Se presenta la metodologia empleada asi como el analisis y discusion de los resultados.

  13. Rapid relief of thalamic pain syndrome induced by vestibular caloric stimulation.

    Science.gov (United States)

    Ramachandran, Vilayanur S; McGeoch, Paul D; Williams, Lisa; Arcilla, Gerard

    2007-06-01

    Central post-stroke pain syndrome develops in a minority of patients following a stroke. The most usual causative lesion involves the lateral thalamus. The classic presentation is of severe, unrelenting pain that involves the entire contralateral half of the body. It is largely refractory to current treatments. We found that in two patients with this condition their pain was substantially improved by vestibular caloric stimulation, whereas placebo procedures had no effect. We proposed that this is because vestibular stimulation activates the posterior insula, which in turn inhibits the generation of pain in the anterior cingulate.

  14. On entropy change measurements around first order phase transitions in caloric materials

    Science.gov (United States)

    Caron, Luana; Doan, Nguyen Ba; Ranno, Laurent

    2017-02-01

    In this work we discuss the measurement protocols for indirect determination of the isothermal entropy change associated with first order phase transitions in caloric materials. The magneto-structural phase transitions giving rise to giant magnetocaloric effects in Cu-doped MnAs and FeRh are used as case studies to exemplify how badly designed protocols may affect isothermal measurements and lead to incorrect entropy change estimations. Isothermal measurement protocols which allow correct assessment of the entropy change around first order phase transitions in both direct and inverse cases are presented.

  15. Tecnologías emergentes para la conservación de alimentos sin calor

    OpenAIRE

    Fernández Molina, Juan José; Gustavo V. Barbosa-Cánovas; Swanson, Barry G.

    2001-01-01

    Not available

    Se han investigado los principios básicos de tres tecnologías emergentes para pasteurizar y esterilizar alimentos sin empleo del calor Mediante numerosos estudios se ha comprobado la efectividad de los campos eléctricos pulsantes de alta intensidad (CEPAI), los pulsos de luz (PL) y los campos magnéticos oscilantes (CMO) en la destrucción de microorganismos y enzimas de sistemas alimentarios. En la inactivación microbiana por CEPA!, el blanco principal es la me...

  16. The minimal caloric test asymmetric response in vertigo-free migraine patients

    Directory of Open Access Journals (Sweden)

    Eliana Teixeira Maranhão

    2016-02-01

    Full Text Available ABSTRACT Vertigo symptoms and subclinical vestibular dysfunctions may occur in migraine. The Minimal Caloric Test (MCT, an easy-to-perform, convenient and yet informative procedure was used to test the vestibular function in 30 vertigo-free migraine patients outside attacks and 30 paired controls. Although not statistically significant, a right-to-left nystagmus duration asymmetry greater than 25% was present in both groups. This difference was greater in the patients group, suggesting the presence of subclinical vestibular imbalance in migraine.

  17. Vertigo and cerebral hemoglobin changes during unilateral caloric stimulation: a near-infrared spectroscopy study.

    Science.gov (United States)

    Iida, Masahiro; Haida, Munetaka; Igarashi, Makoto

    2009-05-01

    The aim of the present study using near-infrared spectroscopy (NIRS) is to evaluate the correlation of cerebral (parieto-temporal lobe) hemoglobin changes and vertiginous sensation during unilateral caloric stimulation. During the hot water (44 degrees C) stimulus, cerebral hemoglobin was increased bilaterally, but it was dominant ipsilaterally. During the unilateral cold water (30 degrees C) stimulus, cerebral hemoglobin was decreased on both sides, especially on the ipsilateral side. Vertigious sensation was strong in cases with marked left-right difference of cerebral hemoglobin changes. The usefulness of NIRS to investigate the relationship between peripheral vestibular organ and vestibular cortex was verified.

  18. Dimensionamiento de intercambiadores de calor de coraza y tubos, con ayuda de computador

    Directory of Open Access Journals (Sweden)

    Gabriel Eduardo Rocha Camino

    2011-02-01

    Full Text Available En este trabajo se plantea el problema de optimizar el diseño de un intercambiador de calor del tipo coraza y tubos, y se propone un método para resolverlo, con base en la técnica del "estudio paramétrico de la respuesta". Además, se muestra la necesidad de utilizar el computador como herramienta para Implementar dicho método, y se describe un programa escrito con tal fin.

  19. Transferencia molecular de calor, masa y/o cantidad de movimiento

    OpenAIRE

    Betancourt Grajales, Ramiro

    2008-01-01

    Este texto fue diseñado para proveer un tratamiento integrado de las tres áreas del transporte: impulso, calor y masa. Las similitudes entre las leyes de flujo permiten aplicar directamente analogías en el cálculo del transporte haciendo una economía en el esfuerzo docente–discente acorde con las pedagogías intensivas. Muchas de las ecuaciones básicas son matemáticamente idénticas cuando se expresan en términos de las variables y densidades de flujo generalizadas. El texto comienza con tra...

  20. Normal physical activity obliterates the deleterious effects of high-caloric intake

    DEFF Research Database (Denmark)

    Krogh-Madsen, Rikke; Pedersen, Maria; Solomon, Thomas

    2013-01-01

    magnetic resonance imaging (MRI)- scans, continuous glucose monitoring (CGM), and oral glucose tolerance tests (OGTT) with stable isotopes were performed before and after the intervention. Both study groups gained the same amount of body weight. However, the inactive group accumulated significantly more....... Therefore, healthy individuals on a high caloric intake were randomized to either 10,000 or 1,500 steps per day for 14 days. Step-number, total energy expenditure, dietary records, neuropsychological tests, maximal oxygen uptake (VO2max), whole body dual-energy X-ray absorptiometry (DXA)- and abdominal...

  1. Targeting energy metabolism in brain cancer with calorically restricted ketogenic diets.

    Science.gov (United States)

    Seyfried, Thomas N; Kiebish, Michael; Mukherjee, Purna; Marsh, Jeremy

    2008-11-01

    Information is presented on the calorically restricted ketogenic diet (CRKD) as an alternative therapy for brain cancer. In contrast to normal neurons and glia, which evolved to metabolize ketone bodies as an alternative fuel to glucose under energy-restricted conditions, brain tumor cells are largely glycolytic due to mitochondrial defects and have a reduced ability to metabolize ketone bodies. The CRKD is effective in managing brain tumor growth in animal models and in patients, and appears to act through antiangiogenic, anti-inflammatory, and proapoptotic mechanisms.

  2. Tolerancia al calor y humedad atmosférica de diferentes grupos raciales de ganado bovino

    OpenAIRE

    2011-01-01

    Objetivo. Comparar algunas respuestas fisiológicas al calor y humedad atmosférica entre bovinos Chinampos (Bos taurus; Ch), ½ Charolais ½ Brahman (CB), Holstein (H) y Jersey (J). Materiales y métodos. Se realizó un estudio en La Paz, México. Se utilizaron 12 vacas H, 10 J, 15 Ch y 8 CB. Durante el verano se midieron cada semana (a las 0600 y 1600 horas) la frecuencia respiratoria (FR) y temperatura rectal (TR). Se registraron las variables climáticas para calcular el índice de temperatura-hum...

  3. Application of cross finned tubes in latent heat storages

    Energy Technology Data Exchange (ETDEWEB)

    Schwind, H.; Wolff, D. (Dortmund Univ. (Germany, F.R.). Lehrstuhl fuer Anlagentechnik); Brose, J. (Dortmund Univ. (Germany, F.R.). Arbeitsgruppe Chemieapparatebau)

    1978-01-01

    Heat storages, utilizing the latent heat of materials have in comparison with sensible heat storages the two fundamental advantages of small storage volumes and constant temperatures during charge and discharge. Known storage systems in the field of industrial heating may be replaced advantageous by latent heat storage systems. A new latent heat storage, applying storage material around vertical arranged cross finned tubes is presented. It results in good heat transfer rates and avoids degredation and stratification of salthydrates during operation. The scaling-up of a single cross finned tube to a compact unit with plate fins seems to be practicable without problems. Some experimental results are presented.

  4. Optical Properties of Drug Metabolites in Latent Fingermarks

    CERN Document Server

    Shen, Yao

    2015-01-01

    Drug metabolites usually have structures of split-ring resonators (SRRs), which might lead to negative permittivity and permeability in electromagnetic field. As a result, in the UV-vis region, the latent fingermarks images of drug addicts and non drug users are inverse. The optical properties of latent fingermarks are quite different between drug addicts and non-drug users. This is a technic superiority for crime scene investigation to distinguish them. In this paper, we calculate the permittivity and permeability of drug metabolites using tight-binding model. The latent fingermarks of smokers and non-smokers are given as an example.

  5. Group Lasso with Overlaps: the Latent Group Lasso approach

    CERN Document Server

    Obozinski, Guillaume; Vert, Jean-Philippe

    2011-01-01

    We study a norm for structured sparsity which leads to sparse linear predictors whose supports are unions of prede ned overlapping groups of variables. We call the obtained formulation latent group Lasso, since it is based on applying the usual group Lasso penalty on a set of latent variables. A detailed analysis of the norm and its properties is presented and we characterize conditions under which the set of groups associated with latent variables are correctly identi ed. We motivate and discuss the delicate choice of weights associated to each group, and illustrate this approach on simulated data and on the problem of breast cancer prognosis from gene expression data.

  6. The latent rationality of risky decisions

    Energy Technology Data Exchange (ETDEWEB)

    Japp, K.P. [Bielefeld Univ. (Germany). Faculty for Sociology

    1999-12-01

    . So rationality will stay latent as the operation of re-entry. It may become manifest as legitimating of something else, for instance as rational choice. In everyday life re-entries emerge as compromise. But compromises conceal the relevant difference. In scientific life re-entries emerge as mixed scanning. But mixed scanning displays a mix, not a difference. And it is always a difference which makes a difference. This remains latent.

  7. Latent Herpes Viruses Reactivation in Astronauts

    Science.gov (United States)

    Mehta, Satish K.; Pierson, Duane L.

    2008-01-01

    Space flight has many adverse effects on human physiology. Changes in multiple systems, including the cardiovascular, musculoskeletal, neurovestibular, endocrine, and immune systems have occurred (12, 32, 38, 39). Alterations in drug pharmacokinetics and pharmacodynamics (12), nutritional needs (31), renal stone formation (40), and microbial flora (2) have also been reported. Evidence suggests that the magnitude of some changes may increase with time in space. A variety of changes in immunity have been reported during both short (.16 days) and long (>30 days) space missions. However, it is difficult to determine the medical significance of these immunological changes in astronauts. Astronauts are in excellent health and in superb physical condition. Illnesses in astronauts during space flight are not common, are generally mild, and rarely affect mission objectives. In an attempt to clarify this issue, we identified the latent herpes viruses as medically important indicators of the effects of space flight on immunity. This chapter demonstrates that space flight leads to asymptomatic reactivation of latent herpes viruses, and proposes that this results from marked changes in neuroendocrine function and immunity caused by the inherent stressfullness of human space flight. Astronauts experience uniquely stressful environments during space flight. Potential stressors include confinement in an unfamiliar, crowded environment, isolation, separation from family, anxiety, fear, sleep deprivation, psychosocial issues, physical exertion, noise, variable acceleration forces, increased radiation, and others. Many of these are intermittent and variable in duration and intensity, but variable gravity forces (including transitions from launch acceleration to microgravity and from microgravity to planetary gravity) and variable radiation levels are part of each mission and contribute to a stressful environment that cannot be duplicated on Earth. Radiation outside the Earth

  8. Avaliação de fluxos de calor e evapotranspiração pelo modelo SEBAL com uso de dados do sensor ASTER Evaluation of heat fluxes and evapotranspiration using SEBAL model with data from ASTER sensor

    Directory of Open Access Journals (Sweden)

    Thiago Veloso dos Santos

    2010-05-01

    Full Text Available O objetivo deste trabalho foi avaliar a eficiência da aplicação do modelo SEBAL em estimar os fluxos de energia em superfície e a evapotranspiração diária, numa extensa área de cultivo de arroz irrigado, no município de Paraíso do Sul, RS, tendo como parâmetros dados do sensor ASTER. As variáveis estudadas constituem importantes parâmetros do tempo e do clima em estudos agrometeorológicos e de racionalização no uso da água. As metodologias convencionais de estimativa desses parâmetros são pontuais e geralmente apresentam incertezas, que aumentam quando o interesse é o comportamento espacial desses parâmetros. Aplicou-se o algoritmo "Surface Energy Balance Algorithm for Land" (SEBAL, em uma imagem do sensor "Advanced Spaceborne Thermal Emission and Reflection Radiometer" (ASTER. As estimativas obtidas foram comparadas com medições em campo, realizadas por uma estação micrometeorológica localizada no interior da área de estudo. As estimativas mais precisas foram as de fluxo de calor sensível e de evapotranspiração diária, e a estimativa que apresentou maior erro foi a do fluxo de calor no solo. A metodologia empregada foi capaz de reproduzir os fluxos de energia em superfície de maneira satisfatória para estudos agrometeorológicos e de rendimento de culturas.The objective of this study was to evaluate the efficiency of SEBAL model in estimating soil surface energy fluxes and daily evapotranspiration for a large area of irrigated rice farms, near the municipality of Paraíso do Sul, RS, Brazil, using data from ASTER sensor. The evaluated variables are important weather and climatic parameters for agrometeorological studies and rationalization of water use. The conventional methodologies for estimating these parameters generally present uncertainties, which increase when concern is in the spatial behavior of such parameters. The Surface Energy Balance Algorithm for Land (SEBAL was applied in an Advanced Spaceborne

  9. Transferência de calor transiente na agitação linear intermitente de latas Transient heat transfer by intermittent shake of cans

    Directory of Open Access Journals (Sweden)

    Homero Ferracini Gumerato

    2007-09-01

    Full Text Available Foi estudada a transferência de calor transiente na agitação linear e intermitente (ALI de embalagens metálicas contendo simulantes de alimentos, objetivando-se sua aplicação em processos de pasteurização ou esterilização e conseqüentes tratamentos térmicos mais eficientes, homogêneos e com produto de melhor qualidade. Foram utilizados quatro meios fluidos simulantes de alimentos de diferentes viscosidades e massas específicas: três óleos e água. Foram combinados efeitos de cinco tratamentos, sendo: meio simulante (4 níveis, espaço livre (3 níveis, freqüência de agitação (4 níveis, amplitude de agitação (2 níveis e posição das latas (4 níveis. Os ensaios de aquecimento e resfriamento foram feitos em tanque com água à temperatura de 98 °C e 17-20 °C, respectivamente. Com os dados de penetração de calor em cada experimento, foram calculados os parâmetros de penetração de calor fh, jh, fc e jc. Os resultados foram modelados utilizando-se grupos de números adimensionais e expressos em termos de Nusselt, Prandtl, Reynolds e funções trigonométricas (com medidas de amplitude e freqüência de agitação, espaço livre e dimensões da embalagem. Foram estabelecidas as duas Equações gerais para as fases de aquecimento e resfriamento: Nu = ReA –0,199.Pr –0,288.sen(xa/AM0,406.cos(xf/FA–1,039.cos((xf/FA.(EL/H.p–4,556 Aquecimento Nu = 0,1295.ReA–0,047.Pr –0,193.sen(xa/AM0,114.cos(xf/FA–0,641.cos((xf/FA.(EL/H.p–2,476 Resfriamento O processo de ALI pode ser aplicado em pasteurizadores ou autoclaves estáticas horizontais e verticais, com modificações simples. Concluiu-se que a ALI aumenta significativamente a taxa de transferência de calor, tanto no aquecimento como no resfriamento.The transient heat transfer during the intermittent and linear shaking of tin plate cans containing simulating food was studied in order to apply this technology in the pasteurization and sterilization processes, achieving

  10. Análise e estimativa dos componentes do balanço de energia em ecossistema de manguezal amazônico Analysis and estimation of energy balance components in amazonian mangrove ecosystem

    Directory of Open Access Journals (Sweden)

    Priscila Lima Pereira

    2013-03-01

    Full Text Available As medições e estimativas dos componentes do balanço de energia foram feitos acima da copa das árvores no ecossistema de manguezal natural, localizada a 30 km da cidade de Bragança-PA, entre novembro de 2002 e agosto de 2003. Os dados foram utilizados para a análise das variações sazonais e horárias do fluxo de calor sensível e calor latente, bem como a avaliação da partição de energia. Os dados meteorológicos foram coletados pela estação meteorológica automática (EMA e os fluxos foram calculados utilizando-se a técnica de covariância de vórtices turbulentos. Os modelos de Penman-Monteith e Shuttleworth foram usados ​​para estimar o fluxo de calor sensível e calor latente. O objetivo deste estudo foi analisar o equilíbrio e a partição de energia no manguezal, assim como fazer uma avaliação do comportamento de modelos empíricos para estimar os fluxos de energia. O saldo de radiação apresentou valores mais elevados no período menos chuvoso. A razão de Bowen mostrou valor geralmente baixo, o que indica que uma proporção maior de energia foi utilizada sob a forma de calor latente. O modelo Shuttleworth é mais eficiente na estimativa de fluxos de calor sensível. Para estimar o fluxo de calor latente do modelo de Penman-Monteith foi mais eficiente durante a estação seca e o modelo Shuttleworth durante a estação chuvosa.Measurements and estimates of the components of energy balance were made above the canopy of trees in natural mangrove ecosystem, located 30 km from the city of Bragança-PA, between November 2002 and August 2003. The data were used in the analysis of seasonal and hourly variations of the sensible and latent heat flows, as well as the evaluation of the energy partition. Meteorological data were collected by the automatic weather station (AWS and the energy flows were calculated using the technique of eddy covariance. The Penman-Monteith and Shuttleworth models were used to estimate the

  11. Latent Infections with Plasmodium ovale Malaria

    Science.gov (United States)

    Miller, Max J.; Marcus, David M.; Cameron, Douglas G.

    1965-01-01

    Two cases of Plasmodium ovale malaria acquired in West Africa appeared as primary delayed attacks after one year's continuous residence in Canada. Both patients took full prophylactic doses of chloroquine before, during, and for several weeks after exposure. The inadequacy of the 4-aminoquinolines for protection against latent benign tertian malaria is noted, and the use of primaquine is recommended. Paroxysms occurred in the evening and were accompanied by severe muscle pain, features considered typical of ovale malaria. One patient showed electrocardiographic changes and clinical signs of cardiac malfunction; these disappeared following specific treatment for malaria. In this age of accelerated travel and international movements of people it is important that physicians in temperate regions be aware of the exotic infections of the tropics, as well as of the need for protective measures for travellers to areas where these diseases are endemic. ImagesFig. 1aFig. 1b,1cFig. 3 a-dFig. 3 e-h PMID:14296004

  12. Predicting Component Failures Using Latent Dirichlet Allocation

    Directory of Open Access Journals (Sweden)

    Hailin Liu

    2015-01-01

    Full Text Available Latent Dirichlet Allocation (LDA is a statistical topic model that has been widely used to abstract semantic information from software source code. Failure refers to an observable error in the program behavior. This work investigates whether semantic information and failures recorded in the history can be used to predict component failures. We use LDA to abstract topics from source code and a new metric (topic failure density is proposed by mapping failures to these topics. Exploring the basic information of topics from neighboring versions of a system, we obtain a similarity matrix. Multiply the Topic Failure Density (TFD by the similarity matrix to get the TFD of the next version. The prediction results achieve an average 77.8% agreement with the real failures by considering the top 3 and last 3 components descending ordered by the number of failures. We use the Spearman coefficient to measure the statistical correlation between the actual and estimated failure rate. The validation results range from 0.5342 to 0.8337 which beats the similar method. It suggests that our predictor based on similarity of topics does a fine job of component failure prediction.

  13. Latent learning in zebrafish (Danio rerio).

    Science.gov (United States)

    Gómez-Laplaza, Luis M; Gerlai, Robert

    2010-04-02

    The zebrafish may represent an excellent compromise between system complexity and practical simplicity for behavioral brain research. It may be particularly appropriate for large scale screening studies whose aim is to identify mutants with altered phenotypes or novel compounds with particular efficacy. For example, the zebrafish may have utility in the analysis of the biological mechanisms of learning and memory. Although learning and memory have been extensively studied and hundreds of underlying molecular mechanisms have been identified, this number may represent only the fraction of genes involved in these complex brain functions. Thus large scale mutagenesis screens may have utility. In order for such screens to succeed, appropriate screening paradigms must be developed. The first step in this research is the characterization of learning and memory capabilities of zebrafish and the development of automatable tasks. Here we show that zebrafish is capable of latent learning, i.e. can acquire memory of their environment after being allowed to explore it. For example, we found experimental zebrafish that experienced an open left tunnel or an open right tunnel of a maze during the unrewarded exploration phase of the test to show the appropriate side bias during a probe trial when they had to swim to a group of conspecifics (the reward). Given that exploration of the maze does not require the presence of the experimenter and the probe trial, during which the subjects are video-recorded and their memory is tested, is short, we argue that the paradigm has utility in high-throughput screening.

  14. Effects of fencamfamine on latent inhibition.

    Science.gov (United States)

    Alves, Cilene R R; Delucia, Roberto; Silva, M Teresa A

    2002-10-01

    The effects of fencamfamine (FCF), an indirect dopamine (DA) agent, were investigated using the latent inhibition (LI) model of schizophrenia. In the LI procedure, rats preexposed (PE) to an unreinforced stimulus show difficulty in subsequent learning of an association in which that stimulus is predictive of an unconditioned stimulus (US). FCF (1.75, 3.5 and 7.0 mg/kg i.p.) yielded an inverse dose-response relationship regarding LI. At 3.5 mg/kg, LI was abolished and no effect was observed at 1.75 and 7.0 mg/kg. The effect of FCF (3.5 mg/kg) on LI was blocked by the antipsychotic risperidone (RIS; 4.0 mg/kg), a D2/5HT2 antagonist. These results confirm the similarity of the behavioral profile of FCF and amphetamine (AMPH). In addition, they provide a further validation of the LI model for psychosis, since RIS was shown to prevent a psychostimulant-induced disruption of LI.

  15. Solar Thermoelectricity via Advanced Latent Heat Storage

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, Michele L.; Rea, J.; Glatzmaier, Greg C.; Hardin, C.; Oshman, C.; Vaughn, J.; Roark, T.; Raade, J. W.; Bradshaw, R. W.; Sharp, J.; Avery, Azure D.; Bobela, David; Bonner, R.; Weigand, R.; Campo, D.; Parilla, Philip A.; Siegel, N. P.; Toberer, Eric S.; Ginley, David S.

    2016-05-31

    We report on a new modular, dispatchable, and cost-effective solar electricity-generating technology. Solar ThermoElectricity via Advanced Latent heat Storage (STEALS) integrates several state-of-the-art technologies to provide electricity on demand. In the envisioned STEALS system, concentrated sunlight is converted to heat at a solar absorber. The heat is then delivered to either a thermoelectric (TE) module for direct electricity generation, or to charge a phase change material for thermal energy storage, enabling subsequent generation during off-sun hours, or both for simultaneous electricity production and energy storage. The key to making STEALS a dispatchable technology lies in the development of a 'thermal valve,' which controls when heat is allowed to flow through the TE module, thus controlling when electricity is generated. The current project addresses each of the three major subcomponents, (i) the TE module, (ii) the thermal energy storage system, and (iii) the thermal valve. The project also includes system-level and techno- economic modeling of the envisioned integrated system and will culminate in the demonstration of a laboratory-scale STEALS prototype capable of generating 3kWe.

  16. Solar thermoelectricity via advanced latent heat storage

    Science.gov (United States)

    Olsen, M. L.; Rea, J.; Glatzmaier, G. C.; Hardin, C.; Oshman, C.; Vaughn, J.; Roark, T.; Raade, J. W.; Bradshaw, R. W.; Sharp, J.; Avery, A. D.; Bobela, D.; Bonner, R.; Weigand, R.; Campo, D.; Parilla, P. A.; Siegel, N. P.; Toberer, E. S.; Ginley, D. S.

    2016-05-01

    We report on a new modular, dispatchable, and cost-effective solar electricity-generating technology. Solar ThermoElectricity via Advanced Latent heat Storage (STEALS) integrates several state-of-the-art technologies to provide electricity on demand. In the envisioned STEALS system, concentrated sunlight is converted to heat at a solar absorber. The heat is then delivered to either a thermoelectric (TE) module for direct electricity generation, or to charge a phase change material for thermal energy storage, enabling subsequent generation during off-sun hours, or both for simultaneous electricity production and energy storage. The key to making STEALS a dispatchable technology lies in the development of a "thermal valve," which controls when heat is allowed to flow through the TE module, thus controlling when electricity is generated. The current project addresses each of the three major subcomponents, (i) the TE module, (ii) the thermal energy storage system, and (iii) the thermal valve. The project also includes system-level and techno- economic modeling of the envisioned integrated system and will culminate in the demonstration of a laboratory-scale STEALS prototype capable of generating 3kWe.

  17. Photoacoustic and Colorimetric Visualization of Latent Fingerprints.

    Science.gov (United States)

    Song, Kai; Huang, Peng; Yi, Chenglin; Ning, Bo; Hu, Song; Nie, Liming; Chen, Xiaoyuan; Nie, Zhihong

    2015-12-22

    There is a high demand on a simple, rapid, accurate, user-friendly, cost-effective, and nondestructive universal method for latent fingerprint (LFP) detection. Herein, we describe a combination imaging strategy for LFP visualization with high resolution using poly(styrene-alt-maleic anhydride)-b-polystyrene (PSMA-b-PS) functionalized gold nanoparticles (GNPs). This general approach integrates the merits of both colorimetric imaging and photoacoustic imaging. In comparison with the previous methods, our strategy is single-step and does not require the signal amplification by silver staining. The PSMA-b-PS functionalized GNPs have good stability, tunable color, and high affinity for universal secretions (proteins/polypeptides/amino acids), which makes our approach general and flexible for visualizing LFPs on different substrates (presumably with different colors) and from different people. Moreover, the unique optical property of GNPs enables the photoacoustic imaging of GNPs-deposited LFPs with high resolution. This allows observation of level 3 hyperfine features of LFPs such as the pores and ridge contours by photoacoustic imaging. This technique can potentially be used to identify chemicals within LFP residues. We believe that this dual-modality imaging of LFPs will find widespread use in forensic investigations and medical diagnostics.

  18. Métodos transientes de troca de calor na determinação das propriedades térmicas de materiais cerâmicos: II - o método do fio quente Thermal properties of ceramic materials by the non-steady techniques: II - the hot wire technique

    Directory of Open Access Journals (Sweden)

    W. N. dos Santos

    2005-12-01

    Full Text Available A condutividade térmica, a difusividade térmica e o calor específico, conhecidos como propriedades térmicas são as três propriedades físicas de um material mais importantes do ponto de vista de cálculos térmicos. Elas são essenciais na determinação dos parâmetros de resistência ao choque térmico em refratários e na determinação dos fatores de dissipação de calor em fornos e fornalhas. A condutividade térmica é um parâmetro importante em problemas envolvendo transferência de calor em regime estacionário, enquanto que a difusividade térmica é importante em estados não estacionários de troca de calor. O calor específico, propriedade importante em altas temperaturas, está associado ao consumo de energia durante o aquecimento. Normalmente essas três propriedades são determinadas separadamente por técnicas e equipamentos individuais. Hoje são conhecidos vários métodos para a determinação da condutividade térmica e difusividade térmica. Recentemente, os métodos transientes de troca de calor têm sido os métodos preferidos na determinação das propriedades térmicas de materiais. Neste trabalho é feita uma descrição e uma análise crítica de um dos métodos mais utilizados na determinação das propriedades térmicas de materiais cerâmicos: o método do fio quente. Com este método é possível determinar simultaneamente, a partir do mesmo transiente térmico experimental, as três propriedades térmicas. Resultados numéricos são também apresentados.Thermal conductivity, thermal diffusivity and specific heat, namely as the thermal properties, are the three most important physical properties of a material that are needed for heat transfer calculations. They are essential in thermal shock parameters determination or in calculations of heat dissipation factors in furnaces and kilns. Thermal conductivity is an important parameter in problems involving steady state heat transfer, while the thermal

  19. Caloric stimulation

    Science.gov (United States)

    ... back and forth during nystagmus. You may have vertigo , and sometimes, you can also have nausea. This ... used to find the cause of: Dizziness or vertigo Hearing loss that may be due to certain ...

  20. Síntesis rigurosa de redes de intercambiadores de calor usando un método híbrido

    OpenAIRE

    J. M. García Hernández; J. M. Ponce Ortega; M. Serna González

    2007-01-01

    En este artículo se presenta un método híbrido para la síntesis de redes de intercambio de calor que incluye el diseño detallado de los intercambiadores de calor. Para realizar esta tarea se combinan las reglas heurísticas del análisis de pliegue con una técnica de programación matemática, junto con un algoritmo de optimización de intercambiadores de calor de coraza y tubos basado en el método riguroso Bell-Delaware. De esta manera, las caídas de presión de las corrientes son tratadas como va...

  1. Gaussian Process Structural Equation Models with Latent Variables

    CERN Document Server

    Silva, Ricardo

    2010-01-01

    In a variety of disciplines such as social sciences, psychology, medicine and economics, the recorded data are considered to be noisy measurements of latent variables connected by some causal structure. This corresponds to a family of graphical models known as the structural equation model with latent variables. While linear non-Gaussian variants have been well-studied, inference in nonparametric structural equation models is still underdeveloped. We introduce a sparse Gaussian process parameterization that defines a non-linear structure connecting latent variables, unlike common formulations of Gaussian process latent variable models. An efficient Markov chain Monte Carlo procedure is described. We evaluate the stability of the sampling procedure and the predictive ability of the model compared against the current practice.

  2. Effect of Boundary Layer Latent Heating on MJO Simulations

    Institute of Scientific and Technical Information of China (English)

    LING Jian; LI Chongyin; ZHOU Wen; JIA Xiaolong; Chidong ZHANG

    2013-01-01

    A latent heating peak in the PBL was detected in a simulation by a global GCM that failed to reproduce Madden-Julian Oscillation (MJO).The latent heating peak in the PBL was generated by very shallow convection,which prevented moisture from being transported to the free troposphere.Large amount of moisture was therefore confined to the PBL,leading to a dry bias in the free atmosphere.Suffering from this dry bias,deep convection became lethargic,and MJO signals failed to occur.When the latent heating peak in the PBL was removed in another simulation,reasonable MJO signals,including the eastward propagation and the structure of its large-scale circulation,appeared.We therefore propose that the excessive latent heating peak in the PBL due to hyperactive shallow convection may be a reason for a lack of MJO signals in some simulations by other GCMs as well.

  3. A solar air collector with integrated latent heat thermal storage

    Science.gov (United States)

    Charvat, Pavel; Ostry, Milan; Mauder, Tomas; Klimes, Lubomir

    2012-04-01

    Simulations of the behaviour of a solar air collector with integrated latent heat thermal storage were performed. The model of the collector was created with the use of coupling between TRNSYS 17 and MATLAB. Latent heat storage (Phase Change Material - PCM) was integrated with the solar absorber. The model of the latent heat storage absorber was created in MATLAB and the model of the solar air collector itself was created in TRNSYS with the use of TYPE 56. The model of the latent heat storage absorber allows specification of the PCM properties as well as other parameters. The simulated air collector was the front and back pass collector with the absorber in the middle of the air cavity. Two variants were considered for comparison; the light-weight absorber made of sheet metal and the heat-storage absorber with the PCM. Simulations were performed for the climatic conditions of the Czech Republic (using TMY weather data).

  4. A solar air collector with integrated latent heat thermal storage

    Directory of Open Access Journals (Sweden)

    Klimes Lubomir

    2012-04-01

    Full Text Available Simulations of the behaviour of a solar air collector with integrated latent heat thermal storage were performed. The model of the collector was created with the use of coupling between TRNSYS 17 and MATLAB. Latent heat storage (Phase Change Material - PCM was integrated with the solar absorber. The model of the latent heat storage absorber was created in MATLAB and the model of the solar air collector itself was created in TRNSYS with the use of TYPE 56. The model of the latent heat storage absorber allows specification of the PCM properties as well as other parameters. The simulated air collector was the front and back pass collector with the absorber in the middle of the air cavity. Two variants were considered for comparison; the light-weight absorber made of sheet metal and the heat-storage absorber with the PCM. Simulations were performed for the climatic conditions of the Czech Republic (using TMY weather data.

  5. Understanding the sufficiency of information for latent fingerprint value determinations.

    Science.gov (United States)

    Ulery, Bradford T; Hicklin, R Austin; Kiebuzinski, George I; Roberts, Maria Antonia; Buscaglia, Joann

    2013-07-10

    A latent print examiner's assessment of the value, or suitability, of a latent impression is the process of determining whether the impression has sufficient information to make a comparison. A "no value" determination preemptively states that no individualization or exclusion determination could be made using the impression, regardless of quality of the comparison prints. Factors contributing to a value determination include clarity and the types, quantity, and relationships of features. These assessments are made subjectively by individual examiners and may vary among examiners. We modeled the relationships between value determinations and feature annotations made by 21 certified latent print examiners on 1850 latent impressions. Minutia count was strongly associated with value determinations. None of the models resulted in a stronger intraexaminer association with "value for individualization" determinations than minutia count alone. The association between examiner annotation and value determinations is greatly limited by the lack of reproducibility of both annotation and value determinations.

  6. Protection from latent inhibition provided by a conditioned inhibitor.

    Science.gov (United States)

    McConnell, Bridget L; Wheeler, Daniel S; Urcelay, Gonzalo P; Miller, Ralph R

    2009-10-01

    Two conditioned suppression experiments with rats investigated the influence on latent inhibition of compounding a Pavlovian conditioned inhibitor with the target cue during preexposure treatment. Results were compared with those of subjects that received conventional latent inhibition training, no preexposure, or preexposure to the target cue in compound with a neutral stimulus. In Experiment 1, greater attenuation of the latent inhibition effect was observed in subjects that received target preexposure in compound with a Pavlovian conditioned inhibitor relative to subjects that received preexposure with a neutral stimulus or to the target alone. In Experiment 2, this protection from latent inhibition was attenuated if the excitor that was used to train the conditioned inhibitor was extinguished between preexposure and target training. The results are consistent with an account offered by the extended comparator hypothesis.

  7. Motivational control of latent inhibition in flavor preference conditioning.

    Science.gov (United States)

    Garcia-Burgos, David; González, Felisa; Hall, Geoffrey

    2013-09-01

    In three experiments, rats given pairings of a neutral flavor with sucrose showed a preference for that flavor when subsequently allowed to choose between it and water. Preexposure to the flavor produced a latent inhibition effect (reduced the size of the preference) when the rats were hungry during the test (Experiments 1 and 2). Rats that were not hungry during the test failed to show latent inhibition (Experiments 1-3). Experiment 3 confirmed that sucrose-flavor pairings were capable of producing a preference even in nonhungry rats. It is argued that the preference shown by rats that are hungry on test depends on a flavor-nutrient association, a form of learning that is susceptible to latent inhibition in the same way as standard conditioning procedures are. The failure to obtain latent inhibition in nonhungry rats suggests that the preference obtained in these conditions depends on a different form of learning that is less susceptible to the effects of stimulus exposure.

  8. A Non-Gaussian Spatial Generalized Linear Latent Variable Model

    KAUST Repository

    Irincheeva, Irina

    2012-08-03

    We consider a spatial generalized linear latent variable model with and without normality distributional assumption on the latent variables. When the latent variables are assumed to be multivariate normal, we apply a Laplace approximation. To relax the assumption of marginal normality in favor of a mixture of normals, we construct a multivariate density with Gaussian spatial dependence and given multivariate margins. We use the pairwise likelihood to estimate the corresponding spatial generalized linear latent variable model. The properties of the resulting estimators are explored by simulations. In the analysis of an air pollution data set the proposed methodology uncovers weather conditions to be a more important source of variability than air pollution in explaining all the causes of non-accidental mortality excluding accidents. © 2012 International Biometric Society.

  9. Transferencia de calor en el secado solar a la intemperie de menas lateríticas ferroniquelíferas

    Directory of Open Access Journals (Sweden)

    Yoalbys Retirado-Mediaceja

    2011-03-01

    Full Text Available En Moa, las menas lateríticas son sometidas a secado solar a la intemperie para reducirles el contenido de humedad antes de incorporarlas al proceso de secado térmico convencional. Este artículo evalúa los procesos de transferencia de calor fundamentales que tienen lugar durante el secado natural con el propósito de determinar el modo predominante de transferencia de calor. En dos pilas de menas lateríticas expuestas a secado solar natural se midieron las variables climatológicas y termodinámicas que influyen en la transferencia de calor por convección y radiación durante el secado y se calcularon, además, los criterios adimensionales para determinar el tipo predominante de convección. Se comprobó que durante el secado solar a la intemperie predomina la convección y que en las condiciones de experimentación analizadas la radiación tuvo una incidencia secundaria. Los resultados evidenciaron que el calor se transfiere por convección libre, forzada y mixta, predominando la forzada, para la cual los coeficientes de transferencia de calor mínimos y máximos mostraron pequeñas variaciones entre ambas pilas. Los flujos de calor por convección promedios fueron 978,74 y 1 156,58 W/m2 , mientras que los flujos por radiación ascendieron a 324,71 y 355,36 W/m2 para las pilas #1 y #2, respectivamente.

  10. Caloric Restriction Effect on Proinflammatory Cytokines, Growth Hormone, and Steroid Hormone Concentrations during Exercise in Judokas.

    Science.gov (United States)

    Abedelmalek, Salma; Chtourou, Hamdi; Souissi, Nizar; Tabka, Zouhair

    2015-01-01

    The aim of this study was to evaluate the effect of caloric restriction on the immune and hormonal responses during exercise in judo athletes. In a randomised order, 11 male judokas (age: 20.45 ± 0.51; height: 1.71 ± 0.3 m; and body weight: 75.9 ± 3.1 kg) participate in this study during a period of weight maintenance (baseline) and after 7 days of caloric restriction (CR). All subjects performed the Special Judo Fitness Test (SJFT) during the two conditions. Values for nutrient intakes were obtained from a 7 d food record kept during a period of weight maintenance and after a 7-day food restriction (-5~6 MJ/day). Our results showed that CR resulted in significant decreases in body weight (P exercise leads to a significant increase in testosterone, cortisol, growth hormone (GH), leukocytes, neutrophils, TNF-α, and IL-6, in both CR and baseline conditions. Compared to baseline, TNF-α and IL-6 were significantly higher during CR condition (P < 0.05). Additionally, CR leads to an increase in cortisol and GH (P < 0.05) and a decrease in testosterone concentrations (P < 0.05).

  11. Caloric vestibular stimulation as a treatment for conversion disorder: A case report and medical hypothesis

    Directory of Open Access Journals (Sweden)

    Michael eNoll-Hussong

    2014-06-01

    Full Text Available Conversion disorder is a medical condition in which a person has paralysis, blindness, or other neurological symptoms that cannot be clearly explained physiologically. To date, there is neither specific nor conclusive treatment. In this paper, we draw together a number of disparate pieces of knowledge to propose a novel intervention to provide transient alleviation for this condition. As caloric vestibular stimulation (CVS has been demonstrated to modulate transiently a variety of cognitive functions associated with brain activations, especially in the temporal-parietal cortex, anterior cingulate cortex, and insular cortex, there is evidence to assume an effect in specific mental disorders. Therefore, we go on to hypothesize that lateralized cold vestibular caloric stimulation will be effective in treating conversion disorder and we present provisional evidence from one patient that supports this conclusion. If our hypothesis is correct, this will be the first time in psychiatry and neurology that a clinically well-known mental disorder, long considered difficult to understand and to treat, is relieved by a simple or common, non-invasive medical procedure.

  12. Spatio-temporal pattern of vestibular information processing after brief caloric stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Marcelli, Vincenzo [Department of Neuroscience, University of Naples ' Federico II' , Naples (Italy); Esposito, Fabrizio [Department of Neuroscience, University of Naples ' Federico II' , Naples (Italy); Department of Cognitive Neurosciences, University of Maastricht, Maastricht (Netherlands)], E-mail: fabrizio.esposito@unina.it; Aragri, Adriana [Department of Neurological Sciences, Second University of Naples, Naples (Italy); Furia, Teresa; Riccardi, Pasquale [Department of Neuroscience, University of Naples ' Federico II' , Naples (Italy); Tosetti, Michela; Biagi, Laura [I.R.C.S.S. ' Stella Maris' , Pisa (Italy); Marciano, Elio [Department of Neuroscience, University of Naples ' Federico II' , Naples (Italy); Di Salle, Francesco [Department of Cognitive Neurosciences, University of Maastricht, Maastricht (Netherlands); I.R.C.S.S. ' Stella Maris' , Pisa (Italy); Department of Neurosciences, University of Pisa, Pisa (Italy)

    2009-05-15

    Processing of vestibular information at the cortical and subcortical level is essential for head and body orientation in space and self-motion perception, but little is known about the neural dynamics of the brain regions of the vestibular system involved in this task. Neuroimaging studies using both galvanic and caloric stimulation have shown that several distinct cortical and subcortical structures can be activated during vestibular information processing. The insular cortex has been often targeted and presented as the central hub of the vestibular cortical system. Since very short pulses of cold water ear irrigation can generate a strong and prolonged vestibular response and a nystagmus, we explored the effects of this type of caloric stimulation for assessing the blood-oxygen-level-dependent (BOLD) dynamics of neural vestibular processing in a whole-brain event-related functional magnetic resonance imaging (fMRI) experiment. We evaluated the spatial layout and the temporal dynamics of the activated cortical and subcortical regions in time-locking with the instant of injection and were able to extract a robust pattern of neural activity involving the contra-lateral insular cortex, the thalamus, the brainstem and the cerebellum. No significant correlation with the temporal envelope of the nystagmus was found. The temporal analysis of the activation profiles highlighted a significantly longer duration of the evoked BOLD activity in the brainstem compared to the insular cortex suggesting a functional de-coupling between cortical and subcortical activity during the vestibular response.

  13. Protective effects of estrogens and caloric restriction during aging on various rat testis parameters

    Institute of Scientific and Technical Information of China (English)

    Khaled Hamden; Dorothee Silandre; Christelle Delalande; Abdelfattah ElFek; Serge Carreau

    2008-01-01

    Aim: To investigate the effects of 17β-estradiol (E2), Peganum harmala extract (PHE) and caloric restriction (CR) on various testis parameters during aging. Methods: Twelve-month-old male rats were treated for 6 months with either E2 or PHE, or submitted to CR (40%). Results: Our results show that estrogens and CR are able to protect the male gonad by preventing the decrease of testosterone and E2 levels as well as the decrease of aromatase and estrogen receptor gene expressions. Indeed, E2, PHE and CR treatments induced an increase in the superoxide dismutase activities and decreased the activity of testicular enzymes: gamma-glutamyl transferase, alkaline phosphatase, lactate deshydrogenase as well as the aspartate and lactate transaminases in aged animals. In addition, the testicular catalase and gluthatione peroxidase activities were enhanced in E2, PHE and CR-treated rats compared to untreated animals at 18 months of age. Moreover, the positive effects of estradiol, PHE and CR were further supported by a lower level of lipid peroxidation. Recovery of spermatogenesis was recorded in treated rats. Conclusion: Besides a low caloric diet which is beneficial for spermatogenesis, a protective antioxydant role of estrogens is suggested. Estrogens delay testicular cell damage, which leads to functional senescence and, therefore, estrogens are helpful in protecting the reproductive functions from the adverse effects exerted by reactive oxygen species (ROS) produced in large quanti-ties in the aged testis.

  14. Mitochondrial oxidative stress, aging and caloric restriction: the protein and methionine connection.

    Science.gov (United States)

    Pamplona, Reinald; Barja, Gustavo

    2006-01-01

    Caloric restriction (CR) decreases aging rate and mitochondrial ROS (MitROS) production and oxidative stress in rat postmitotic tissues. Low levels of these parameters are also typical traits of long-lived mammals and birds. However, it is not known what dietary components are responsible for these changes during CR. It was recently observed that 40% protein restriction without strong CR also decreases MitROS generation and oxidative stress. This is interesting because protein restriction also increases maximum longevity (although to a lower extent than CR) and is a much more practicable intervention for humans than CR. Moreover, it was recently found that 80% methionine restriction substituting it for l-glutamate in the diet also decreases MitROS generation in rat liver. Thus, methionine restriction seems to be responsible for the decrease in ROS production observed in caloric restriction. This is interesting because it is known that exactly that procedure of methionine restriction also increases maximum longevity. Moreover, recent data show that methionine levels in tissue proteins negatively correlate with maximum longevity in mammals and birds. All these suggest that lowering of methionine levels is involved in the control of mitochondrial oxidative stress and vertebrate longevity by at least two different mechanisms: decreasing the sensitivity of proteins to oxidative damage, and lowering of the rate of ROS generation at mitochondria.

  15. Remission of anosognosia for right hemiplegia and neglect after caloric vestibular stimulation.

    Science.gov (United States)

    Ronchi, Roberta; Rode, Gilles; Cotton, François; Farnè, Alessandro; Rossetti, Yves; Jacquin-Courtois, Sophie

    2013-01-01

    Neglect and related phenomena, as anosognosia for hemiplegia and somatoparaphrenia, are often associated to right-hemisphere lesions. These deficits can be alleviated by caloric vestibular stimulation, but little is known about the efficacy of this physiological intervention on neglect following left-hemisphere lesions. Here we report the case of an ambidextrous left brain-damaged patient with severe right personal and extrapersonal neglect, anosognosia for right hemiplegia and somatoparaphrenia. These symptoms co-occurred with more typical manifestations of left-brain damage, such as aphasia and apraxia. Neurological examination revealed right hemiplegia, hemianesthesia and hemianopia. Visuo-spatial tests for personal and extrapersonal neglect, as well as an anosognosia questionnaire, were submitted before and after caloric vestibular stimulation. Results showed a dramatic improvement of anosognosia for hemiplegia and neglect; no change was observed for the remaining deficits. The results confirm the notion of the selectivity of vestibular stimulation for neglect and related disorders and extend this notion by showing that similar effects can be obtained after lesion of the left hemisphere, suggesting that similar mechanisms are responsible for left- and right-sided neglect. Such a peculiar association of language and visuo-spatial disorders jointly present after a left-sided lesion opens the question of the link between handedness and lateralization of cognitive functions.

  16. Coeficientes de transferencia de calor en enfriadores de mineral laterítico a escala piloto

    Directory of Open Access Journals (Sweden)

    Ángel Legrá-Legrá

    2009-03-01

    Full Text Available En la Planta de Hornos de Reducción de la empresa niquelera Ernesto Guevara las elevadas temperaturas del mineral reducido a la salida de los enfriadores (coolers afectan el desarrollo eficiente del proceso de lixiviación. Se realizó una investigación, a escala piloto, en los enfriadores de mineral reducido con el fin de evaluar el comportamiento de los parámetros de transferencia de calor que caracterizan el proceso; para ello se registraron los valores de temperatura del agua y del flujo y la temperatura del mineral, tanto a la entrada como a la salida de la instalación, para valores de flujos de 10 y 19 l/min. Como resultado se obtuvo el procedimiento de cálculo para determinar los coeficientes superficiales de transferencia de calor por unidad de longitud. Se encontró que en los enfriadores de mineral reducido predominan la conducción y radiación del mineral a la pared interior del cilindro cubierta por el sólido así como la convección y evaporación del agua al medio que permite dirigir las acciones hacia estos elementos para aumentar la eficiencia de la instalación.

  17. Transferencia de calor en la colada continua de aceros. I parte. El molde

    Directory of Open Access Journals (Sweden)

    Cicutti, C.

    1997-10-01

    Full Text Available The continuous casting mold plays the important role of receiving the liquid steel and allowing an uniform and defect free solidified skin to be developed. In this work, the different heat transfer mechanisms which are present from the liquid steel to the mold cooling water are reviewed. The effect of operating variables on heat extraction and the relationship between global and distributed heat flux are also analyzed.

    El molde de colada continua cumple la importante función de recibir el acero líquido y permitir que se desarrolle una capa solidificada uniforme y libre de defectos. En este trabajo se revisan los distintos mecanismos implicados en el proceso de transferencia de calor, desde el acero líquido hasta el agua de refrigeración del molde. Se analiza también el efecto de las distintas variables de funcionamiento en la extracción calórica producida y la relación entre el flujo global de calor y su distribución a lo largo del molde.

  18. Caloric restriction and resveratrol promote longevity through the Sirtuin-1-dependent induction of autophagy.

    Science.gov (United States)

    Morselli, E; Maiuri, M C; Markaki, M; Megalou, E; Pasparaki, A; Palikaras, K; Criollo, A; Galluzzi, L; Malik, S A; Vitale, I; Michaud, M; Madeo, F; Tavernarakis, N; Kroemer, G

    2010-01-01

    Caloric restriction and autophagy-inducing pharmacological agents can prolong lifespan in model organisms including mice, flies, and nematodes. In this study, we show that transgenic expression of Sirtuin-1 induces autophagy in human cells in vitro and in Caenorhabditis elegans in vivo. The knockdown or knockout of Sirtuin-1 prevented the induction of autophagy by resveratrol and by nutrient deprivation in human cells as well as by dietary restriction in C. elegans. Conversely, Sirtuin-1 was not required for the induction of autophagy by rapamycin or p53 inhibition, neither in human cells nor in C. elegans. The knockdown or pharmacological inhibition of Sirtuin-1 enhanced the vulnerability of human cells to metabolic stress, unless they were stimulated to undergo autophagy by treatment with rapamycin or p53 inhibition. Along similar lines, resveratrol and dietary restriction only prolonged the lifespan of autophagy-proficient nematodes, whereas these beneficial effects on longevity were abolished by the knockdown of the essential autophagic modulator Beclin-1. We conclude that autophagy is universally required for the lifespan-prolonging effects of caloric restriction and pharmacological Sirtuin-1 activators.

  19. Caloric restriction promotes cell survival in a mouse model of normal tension glaucoma

    Science.gov (United States)

    Guo, Xiaoli; Kimura, Atsuko; Azuchi, Yuriko; Akiyama, Goichi; Noro, Takahiko; Harada, Chikako; Namekata, Kazuhiko; Harada, Takayuki

    2016-01-01

    Glaucoma is characterized by progressive degeneration of retinal ganglion cells (RGCs) and their axons. We previously reported that loss of glutamate transporters (EAAC1 or GLAST) in mice leads to RGC degeneration that is similar to normal tension glaucoma and these animal models are useful in examining potential therapeutic strategies. Caloric restriction has been reported to increase longevity and has potential benefits in injury and disease. Here we investigated the effects of every-other-day fasting (EODF), a form of caloric restriction, on glaucomatous pathology in EAAC1−/− mice. EODF suppressed RGC death and retinal degeneration without altering intraocular pressure. Moreover, visual impairment was ameliorated with EODF, indicating the functional significance of the neuroprotective effect of EODF. Several mechanisms associated with this neuroprotection were explored. We found that EODF upregulated blood β-hydroxybutyrate levels and increased histone acetylation in the retina. Furthermore, it elevated retinal mRNA expression levels of neurotrophic factors and catalase, whereas it decreased oxidative stress levels in the retina. Our findings suggest that EODF, a safe, non-invasive, and low-cost treatment, may be available for glaucoma therapy. PMID:27669894

  20. Conceptos esenciales de la transmisión de calor en una edificación

    Directory of Open Access Journals (Sweden)

    Safranez, Carlos

    1981-05-01

    Full Text Available Dirigiéndose esta publicación al técnico del ramo de la Construcción, poco familiarizado con los problemas de aislamiento térmico, se presenta una breve exposición de los conceptos esenciales de la transmisión de calor en una edificación. Se exponen ejemplos del cálculo de la resistencia térmica y de la curva de temperatura de una cubierta plana y de un sótano. Se analiza la repercusión del aislamiento térmico sobre el consumo de energía con tiempo frío y tiempo caluroso. Sobre la posibilidad de producirse condensaciones, y sobre la temperatura a que estará expuesta la membrana impermeabilizante de un sótano, debido a la calefacción, con el fin de que no sobrepase los límites fijados. Finalmente, se dan a conocer dos ábacos para la determinación del coeficiente K de la transmisión de calor y de la resistencia térmica R, de distintos tipos de aislamiento.

  1. Caloric Restriction Effect on Proinflammatory Cytokines, Growth Hormone, and Steroid Hormone Concentrations during Exercise in Judokas

    Directory of Open Access Journals (Sweden)

    Salma Abedelmalek

    2015-01-01

    Full Text Available The aim of this study was to evaluate the effect of caloric restriction on the immune and hormonal responses during exercise in judo athletes. In a randomised order, 11 male judokas (age: 20.45 ± 0.51; height: 1.71 ± 0.3 m; and body weight: 75.9 ± 3.1 kg participate in this study during a period of weight maintenance (baseline and after 7 days of caloric restriction (CR. All subjects performed the Special Judo Fitness Test (SJFT during the two conditions. Values for nutrient intakes were obtained from a 7 d food record kept during a period of weight maintenance and after a 7-day food restriction (−5~6 MJ/day. Our results showed that CR resulted in significant decreases in body weight (P<0.05 and performance (P<0.05. However, heart rate and SJFT index (P<0.05 increase significantly during CR in comparison to baseline. Moreover, exercise leads to a significant increase in testosterone, cortisol, growth hormone (GH, leukocytes, neutrophils, TNF-α, and IL-6, in both CR and baseline conditions. Compared to baseline, TNF-α and IL-6 were significantly higher during CR condition (P<0.05. Additionally, CR leads to an increase in cortisol and GH (P<0.05 and a decrease in testosterone concentrations (P<0.05.

  2. Latent-failure risk estimates for computer control

    Science.gov (United States)

    Dunn, William R.; Folsom, Rolfe A.; Green, Owen R.

    1991-01-01

    It is shown that critical computer controls employing unmonitored safety circuits are unsafe. Analysis supporting this result leads to two additional, important conclusions: (1) annual maintenance checks of safety circuit function do not, as widely believed, eliminate latent failure risk; (2) safety risk remains even if multiple, series-connected protection circuits are employed. Finally, it is shown analytically that latent failure risk is eliminated when continuous monitoring is employed.

  3. Time-resolved imaging of latent fingerprints with nanosecond resolution

    Science.gov (United States)

    Seah, L. K.; Dinish, U. S.; Ong, S. K.; Chao, Z. X.; Murukeshan, V. M.

    2004-07-01

    Imaging of latent fingerprints using time-resolved (TR) method offers a broader platform to eliminate the unwanted background emission. In this paper, a novel TR imaging technique is demonstrated and implemented, which facilitates the detection of latent fingerprints with nanosecond resolution. Simulated experiments were carried out with two overlapping fingerprints treated with two fluorescent powders having different lifetimes in nanosecond range. The dependence of the fluorescence emission intensity in nanosecond resolution of TR imaging is also revealed.

  4. LATENT INHIBITION AND PSYCHOMETRICALLY DEFINED SCHIZOTYPY: AN EXPERIMENTAL INVESTIGATION

    OpenAIRE

    Tsakanikos, Elias

    2003-01-01

    The review of the literature suggests that the interpretation of the disruption of latent inhibition within the schizophrenia continuum remains elusive due to a number of methodological and theoretical problems. This thesis adopted a personality-based approach to experimental psychopathology testing alternative interpretations of latent inhibition deficits as a function of psychotic-like features in non-clinical participants. Results from 12 Experiments are discussed in terms of a two-compone...

  5. Fitting Latent Cluster Models for Networks with latentnet

    Directory of Open Access Journals (Sweden)

    Pavel N. Krivitsky

    2007-12-01

    Full Text Available latentnet is a package to fit and evaluate statistical latent position and cluster models for networks. Hoff, Raftery, and Handcock (2002 suggested an approach to modeling networks based on positing the existence of an latent space of characteristics of the actors. Relationships form as a function of distances between these characteristics as well as functions of observed dyadic level covariates. In latentnet social distances are represented in a Euclidean space. It also includes a variant of the extension of the latent position model to allow for clustering of the positions developed in Handcock, Raftery, and Tantrum (2007.The package implements Bayesian inference for the models based on an Markov chain Monte Carlo algorithm. It can also compute maximum likelihood estimates for the latent position model and a two-stage maximum likelihood method for the latent position cluster model. For latent position cluster models, the package provides a Bayesian way of assessing how many groups there are, and thus whether or not there is any clustering (since if the preferred number of groups is 1, there is little evidence for clustering. It also estimates which cluster each actor belongs to. These estimates are probabilistic, and provide the probability of each actor belonging to each cluster. It computes four types of point estimates for the coefficients and positions: maximum likelihood estimate, posterior mean, posterior mode and the estimator which minimizes Kullback-Leibler divergence from the posterior. You can assess the goodness-of-fit of the model via posterior predictive checks. It has a function to simulate networks from a latent position or latent position cluster model.

  6. Influencia del contexto hidrogeológico en la eficiencia de los sistemas cerrados de bomba de calor

    OpenAIRE

    Folch Sancho, Albert; Goma Roca, Albert; Jimenez Parras, Santos; Zarroca HErnandez, Mario; Bach Plaza, Joan; Mas Pla, Josep

    2013-01-01

    Los sistemas geotérmicos de bomba de calor se caracterizan por presentar una elevada eficiencia energética en condiciones de óptimo funcionamiento. Aun así, su productividad se ve condicionada por las características geológicas e hidrogeológicas del medio. El presente estudio centra su interés en los sistemas cerrados verticales, dado que en muchos casos no se contabiliza el efecto del flujo de agua subterránea de forma adecuada. En este trabajo se evalúa el transporte de calor en 4 contextos...

  7. Transferencia de calor en el secado solar a la intemperie de menas lateríticas ferroniquelíferas

    OpenAIRE

    Yoalbys Retirado-Mediaceja; Marbelis Lamorú-Urgelles; Ever Góngora-Leyva; Enrique Torres-Tamayo; Benigno Leyva-de la Cruz; Daynelis García-Batista

    2011-01-01

    En Moa, las menas lateríticas son sometidas a secado solar a la intemperie para reducirles el contenido de humedad antes de incorporarlas al proceso de secado térmico convencional. Este artículo evalúa los procesos de transferencia de calor fundamentales que tienen lugar durante el secado natural con el propósito de determinar el modo predominante de transferencia de calor. En dos pilas de menas lateríticas expuestas a secado solar natural se midieron las variables climatológicas y termodinám...

  8. The calorically restricted ketogenic diet, an effective alternative therapy for malignant brain cancer

    Directory of Open Access Journals (Sweden)

    Zhou Weihua

    2007-02-01

    Full Text Available Abstract Background Malignant brain cancer persists as a major disease of morbidity and mortality in adults and is the second leading cause of cancer death in children. Many current therapies for malignant brain tumors fail to provide long-term management because they ineffectively target tumor cells while negatively impacting the health and vitality of normal brain cells. In contrast to brain tumor cells, which lack metabolic flexibility and are largely dependent on glucose for growth and survival, normal brain cells can metabolize both glucose and ketone bodies for energy. This study evaluated the efficacy of KetoCal®, a new nutritionally balanced high fat/low carbohydrate ketogenic diet for children with epilepsy, on the growth and vascularity of a malignant mouse astrocytoma (CT-2A and a human malignant glioma (U87-MG. Methods Adult mice were implanted orthotopically with the malignant brain tumors and KetoCal® was administered to the mice in either unrestricted amounts or in restricted amounts to reduce total caloric intake according to the manufacturers recommendation for children with refractory epilepsy. The effects KetoCal® on tumor growth, vascularity, and mouse survival were compared with that of an unrestricted high carbohydrate standard diet. Results KetoCal® administered in restricted amounts significantly decreased the intracerebral growth of the CT-2A and U87-MG tumors by about 65% and 35%, respectively, and significantly enhanced health and survival relative to that of the control groups receiving the standard low fat/high carbohydrate diet. The restricted KetoCal® diet reduced plasma glucose levels while elevating plasma ketone body (β-hydroxybutyrate levels. Tumor microvessel density was less in the calorically restricted KetoCal® groups than in the calorically unrestricted control groups. Moreover, gene expression for the mitochondrial enzymes, β-hydroxybutyrate dehydrogenase and succinyl-CoA: 3-ketoacid Co

  9. Latent class instrumental variables: a clinical and biostatistical perspective.

    Science.gov (United States)

    Baker, Stuart G; Kramer, Barnett S; Lindeman, Karen S

    2016-01-15

    In some two-arm randomized trials, some participants receive the treatment assigned to the other arm as a result of technical problems, refusal of a treatment invitation, or a choice of treatment in an encouragement design. In some before-and-after studies, the availability of a new treatment changes from one time period to this next. Under assumptions that are often reasonable, the latent class instrumental variable (IV) method estimates the effect of treatment received in the aforementioned scenarios involving all-or-none compliance and all-or-none availability. Key aspects are four initial latent classes (sometimes called principal strata) based on treatment received if in each randomization group or time period, the exclusion restriction assumption (in which randomization group or time period is an instrumental variable), the monotonicity assumption (which drops an implausible latent class from the analysis), and the estimated effect of receiving treatment in one latent class (sometimes called efficacy, the local average treatment effect, or the complier average causal effect). Since its independent formulations in the biostatistics and econometrics literatures, the latent class IV method (which has no well-established name) has gained increasing popularity. We review the latent class IV method from a clinical and biostatistical perspective, focusing on underlying assumptions, methodological extensions, and applications in our fields of obstetrics and cancer research.

  10. Cultured Vestibular Ganglion Neurons Demonstrate Latent HSV1 Reactivation

    Science.gov (United States)

    Roehm, Pamela C.; Camarena, Vladimir; Nayak, Shruti; Gardner, James B.; Wilson, Angus; Mohr, Ian; Chao, Moses V.

    2013-01-01

    Objectives/Hypothesis Vestibular neuritis is a common cause of both acute and chronic vestibular dysfunction. Multiple pathologies have been hypothesized to be the causative agent of vestibular neuritis; however, whether herpes simplex type I (HSV1) reactivation occurs within the vestibular ganglion has not been demonstrated previously by experimental evidence. We developed an in vitro system to study HSV1 infection of vestibular ganglion neurons (VGNs) using a cell culture model system. Study design basic science study. Results Lytic infection of cultured rat VGNs was observed following low viral multiplicity of infection (MOI). Inclusion of acyclovir suppressed lytic replication and allowed latency to be established. Upon removal of acyclovir, latent infection was confirmed with reverse-transcription polymerase chain reaction and by RNA fluorescent in situ hybridization for the latency-associated transcript (LAT). 29% cells in latently infected cultures were LAT positive. The lytic IPC27 transcript was not detected by reverse-transcription polymerase chain reaction (RT-PCR). Reactivation of HSV1 occurred at a high frequency in latently infected cultures following treatment with trichostatin A (TSA), a histone deactylase inhibitor. Conclusions VGNs can be both lytically and latently infected with HSV1. Furthermore, latently infected VGNs can be induced to reactivate using TSA. This demonstrates that reactivation of latent HSV1 infection in the vestibular ganglion can occur in a cell culture model, and suggests that reactivation of HSV1 infection a plausible etiologic mechanism of vestibular neuritis. PMID:21898423

  11. Comparing the context specificity of extinction and latent inhibition.

    Science.gov (United States)

    Miller, Ralph R; Laborda, Mario A; Polack, Cody W; Miguez, Gonzalo

    2015-12-01

    Exposure to a cue alone either before (i.e., latent inhibition treatment) or after (i.e., extinction) the cue is paired with an unconditioned stimulus results in attenuated conditioned responding to the cue. Here we report two experiments in which potential parallels between the context specificity of the effects of extinction and latent inhibition treatments were directly compared in a lick suppression preparation with rats. The reversed ordering of conditioning and nonreinforcement in extinction and latent inhibition designs allowed us to examine the effect of training order on the context specificity of what is learned given phasic reinforcement and nonreinforcement of a target cue. Experiment 1 revealed that when conditioned-stimulus (CS) conditioning and CS nonreinforcement were administered in the same context, both extinction and latent inhibition treatments had reduced impacts on test performance, relative to excitatory conditioning when testing occurred outside the treatment context. Similarly, Experiment 2 showed that when conditioning was administered in one context and nonreinforcement was administered in a second context, the effects of both extinction and latent inhibition treatments were attenuated when testing occurred in a neutral context, relative to the context in which the CS was nonreinforced. The observed context specificity of extinction and latent inhibition treatments has been previously reported in both cases, but not in a single experiment under otherwise identical conditions. The results of the two experiments convergently suggest that memory of nonreinforcement becomes context dependent after a cue is both reinforced and nonreinforced, independent of the order of training.

  12. A latent class distance association model for cross-classified data with a categorical response variable.

    Science.gov (United States)

    Vera, José Fernando; de Rooij, Mark; Heiser, Willem J

    2014-11-01

    In this paper we propose a latent class distance association model for clustering in the predictor space of large contingency tables with a categorical response variable. The rows of such a table are characterized as profiles of a set of explanatory variables, while the columns represent a single outcome variable. In many cases such tables are sparse, with many zero entries, which makes traditional models problematic. By clustering the row profiles into a few specific classes and representing these together with the categories of the response variable in a low-dimensional Euclidean space using a distance association model, a parsimonious prediction model can be obtained. A generalized EM algorithm is proposed to estimate the model parameters and the adjusted Bayesian information criterion statistic is employed to test the number of mixture components and the dimensionality of the representation. An empirical example highlighting the advantages of the new approach and comparing it with traditional approaches is presented.

  13. Caloric Intake from Fast Food among Children and Adolescents in the United States, 2011-2012. NCHS Data Brief. Number 213

    Science.gov (United States)

    Vikraman, Sundeep; Fryar, Cheryl D.; Ogden, Cynthia L.

    2015-01-01

    Consumption of fast food has been linked to weight gain in adults. Fast food has also been associated with higher caloric intake and poorer diet quality in children and adolescents. From 1994 through 2006, caloric intake from fast food increased from 10% to 13% among children aged 2-18 years. This report presents the most recent data on the…

  14. Models comparative study for heat storage in fixed beds; Estudo comparativo de modelos para armazenamento de calor em leitos fixos

    Energy Technology Data Exchange (ETDEWEB)

    Stuginski Junior, Rubens

    1991-07-01

    This work presents comparative results of a numerical investigation of four possible models for the prediction of thermal performance of fixed bed storage units and their thermal design. These models includes Schumann's model, the radial dispersion model, a model that include both axial heat conduction in the fluid phase and admits thermal gradient in the solids particles and finally a two dimensional single phase model. For each of these models a computer code was written and tested to evaluate the computing time of same data and analyze any other computational problems. The tests of thermal performance included particle size, porosity, particle material, flow rate, inlet temperature and heat losses form tank walls and extremities. Dynamics behaviour of the storage units due to transient variation in either flow rate or inlet temperature was also investigated. The results presented include temperature gradients, pressure drop and heat storage. The results obtained are very useful for analysis and design of fixed bed storage units. (author)

  15. Latent viral immune inflammatory response model for chronic multisymptom illness.

    Science.gov (United States)

    Maloney, Sean R; Jensen, Susan; Gil-Rivas, Virginia; Goolkasian, Paula

    2013-03-01

    A latent viral immune inflammatory response (LVIIR) model is presented which integrates factors that contribute to chronic multisymptom illness (CMI) in both the veteran and civilian populations. The LVIIR model for CMI results from an integration of clinical experience with a review of the literature in four distinct areas: (1) studies of idiopathic multisymptom illness in the veteran population including two decades of research on Gulf War I veterans with CMI, (2) new evidence supporting the existence of chronic inflammatory responses to latent viral antigens and the effect these responses may have on the nervous system, (3) recent discoveries concerning the role of vitamin D in maintaining normal innate and adaptive immunity including suppression of latent viruses and regulation of the immune inflammatory response, and (4) the detrimental effects of extreme chronic repetitive stress (ECRS) on the immune and nervous systems. The LVIIR model describes the pathophysiology of a pathway to CMI and presents a new direction for the clinical assessment of CMI that includes the use of neurological signs from a physical exam, objective laboratory data, and a new proposed latent viral antigen-antibody imaging technique for the peripheral and central nervous system. The LVIIR model predicts that CMI can be treated by a focus on reversal of immune system impairment, suppression of latent viruses and their antigens, and healing of nervous system tissue damaged by chronic inflammation associated with latent viral antigens and by ECRS. In addition, the LVIIR model suggests that maintaining optimal serum 25 OH vitamin D levels will maximize immune system suppression of latent viruses and their antigens and will minimize immune system inflammation. This model also emphasizes the importance of decreasing ECRS to improve immune system function and to minimize nervous system injury from excess serum glucocorticoid levels. The proposed model supports growing evidence that increasing

  16. Aspectos fisiológicos e bioquímicos da germinação de sementes de alface em diferentes temperaturas

    Directory of Open Access Journals (Sweden)

    Hugo Cesar Rodrigues Moreira Catão

    2014-04-01

    Full Text Available O objetivo deste trabalho foi avaliar os padrões eletroforéticos das proteínas resistentes ao calor e a atividade da enzima endo-β-mananase durante a germinação de sementes de alface, em alta temperatura. Sementes de oito cultivares de alface foram submetidas aos testes de germinação, primeira contagem e emergência em duas temperaturas, 20 e 35ºC. Foram calculados o índice de velocidade de germinação (IVG e o índice de velocidade de emergência (IVE. Avaliou-se, também, a expressão das proteínas resistentes ao calor e da enzima endo-β-mananase, para todos os tratamentos. Utilizou-se o delineamento experimental inteiramente casualizado, em arranjo fatorial 2x8, com duas temperaturas e oito cultivares. A maior germinação é observada a 35ºC na cultivar Everglades, considerada termotolerante. Os padrões de proteínas resistentes ao calor em sementes de alface apresentam bandas específicas na cultivar Everglades, a 35ºC. A atividade da enzima endo-β-mananase é maior na cultivar Everglades, nessa temperatura. Essa cultivar tem potencial para utilização em programas de melhoramento de alface com vistas à tolerância a altas temperaturas durante a germinação.

  17. Latent Virus Reactivation: From Space to Earth

    Science.gov (United States)

    Mehta, Satish K.; Cohrs, Randall J.; Gilden, Donald H.; Tyring, Stephen K.; Castro, Victoria A.; Ott, C. Mark; Pierson, Duane L.

    2010-01-01

    Reactivation of latent viruses is a recognized consequence of decreased immunity. More recently viral reactivation has been identified as an important in vivo indicator of clinically relevant immune changes. Viral reactivation can be determined quickly and easily by the presence of virus in saliva and other body fluids. Real-time polymerase chain reaction (PCR) is a highly sensitive and specific molecular method to detect the presence of specific viral DNA. Studies in astronauts demonstrated that herpes simplex virus type 1(HSV-1), Epstein-Barr Virus (EBV), cytomegalovirus (CMV), and varicella zoster virus (VZV) reactivate at rates above normal during and after spaceflight in response to moderately decreased T-cell immunity. This technology was expanded to patients on Earth beginning with human immune deficiency virus (HIV) immuno-compromised patients. The HIV patients shed EBV in saliva at rates 9-fold higher than observed in astronauts demonstrating that the level of EBV shedding reflects the severity of impaired immunity. Whereas EBV reactivation is not expected to produce serious effects in astronauts on missions of 6 months or less, VZV reactivation in astronauts could produce shingles. Reactivation of live, infectious VZV in astronauts with no symptoms was demonstrated in astronauts during and after spaceflight. We applied our technology to study VZV-induced shingles in patients. In a study of 54 shingles patients, we showed salivary VZV was present in every patient on the day antiviral (acyclovir) treatment was initiated. Pain and skin lesions decreased with antiviral treatment. Corresponding decreases in levels of VZV were also observed and accompanied recovery. Although the level of VZV in shingles patients before the treatment was generally higher than those found in astronauts, lower range of VZV numbers in shingles patients overlapped with astronaut s levels. This suggests a potential risk of shingles to astronauts resulting from reactivation of VZV. In

  18. Short-term caloric restriction normalizes hypothalamic neuronal responsiveness to glucose ingestion in patients with type 2 diabetes

    NARCIS (Netherlands)

    Teeuwisse, W.M.; Widya, R.L.; Paulides, M.; Lamb, H.J.; Smit, J.W.A.; Roos, A. de; Buchem, M.A. van; Pijl, H.; Grond, J. van der

    2012-01-01

    The hypothalamus is critically involved in the regulation of feeding. Previous studies have shown that glucose ingestion inhibits hypothalamic neuronal activity. However, this was not observed in patients with type 2 diabetes. Restoring energy balance by reducing caloric intake and losing weight are

  19. Caloric Restriction in Lean and Obese Strains of Laboratory Rat: Effects on Body Composition, Metabolism, Growth, and Overall Health

    Science.gov (United States)

    NEW FINDINGS: What is the central question of this study? How do lean and obese rats respond physiologically to caloric restriction? What is the main finding and its importance? Obese rats show marked benefits compared with lean animals. Reduced body fat is associated with improv...

  20. Cardiovascular flexibility in middle-aged overweight South Asians vs. white Caucasians: response to short-term caloric restriction

    NARCIS (Netherlands)

    Schinkel, L.D. van; Bakker, L.E.; Jonker, J.T.; Roos, A. de; Pijl, H.; Meinders, A.E.; Jazet, I.M.; Lamb, H.J.; Smit, J.W.A.

    2015-01-01

    BACKGROUND AND AIMS: South Asians have a higher risk of developing cardiovascular disease than white Caucasians. The underlying cause is unknown, but might be related to higher cardiac susceptibility to metabolic disorders. Short-term caloric restriction (CR) can be used as a metabolic stress test t

  1. Behavioural changes are a major contributing factor in the reduction of sarcopenia in caloric-restricted ageing mice

    NARCIS (Netherlands)

    Norren, van K.; Rusli, F.; Dijk, van M.; Lute, C.; Nagel, J.C.; Dijk, F.J.; Dwarkasing, J.T.; Boekschoten, M.V.; Luiking, Y.; Witkamp, R.F.; Müller, M.R.; Steegenga, W.T.

    2015-01-01

    Background - In rodent models, caloric restriction (CR) with maintenance of adequate micronutrient supply has been reported to increase lifespan and to reduce age-induced muscle loss (sarcopenia) during ageing. In the present study, we further investigated effects of CR on the onset and severity of

  2. Exercise and Caloric Restriction Alter the Immune System of Mice Submitted to a High-Fat Diet

    Directory of Open Access Journals (Sweden)

    Frederick Wasinski

    2013-01-01

    Full Text Available As the size of adipocytes increases during obesity, the establishment of resident immune cells in adipose tissue becomes an important source of proinflammatory mediators. Exercise and caloric restriction are two important, nonpharmacological tools against body mass increase. To date, their effects on the immune cells of adipose tissue in obese organisms, specifically when a high-fat diet is consumed, have been poorly investigated. Thus, after consuming a high-fat diet, mice were submitted to chronic swimming training or a 30% caloric restriction in order to investigate the effects of both interventions on resident immune cells in adipose tissue. These strategies were able to reduce body mass and resulted in changes in the number of resident immune cells in the adipose tissue and levels of cytokines/chemokines in serum. While exercise increased the number of NK cells in adipose tissue and serum levels of IL-6 and RANTES, caloric restriction increased the CD4+/CD8+ cell ratio and MCP-1 levels. Together, these data demonstrated that exercise and caloric restriction modulate resident immune cells in adipose tissues differently in spite of an equivalent body weight reduction. Additionally, the results also reinforce the idea that a combination of both strategies is better than either individually for combating obesity.

  3. A two year randomized controlled trial of human caloric restriction: feasibility and effects on predictors of health span and longevity

    Science.gov (United States)

    Background: Caloric restriction (CR), energy intake reduced below ad libitum (AL) intake, increases life span in many species. The implications for humans can be clarified by randomized controlled trials of CR. Methods: To determine CRs feasibility, safety, and effects on predictors of longevity, di...

  4. Comparison of Vestibular Evoked Myogenic Potential and Caloric Tests Findings in Noise Induced Hearing Loss-Affected and Healthy Individuals

    Directory of Open Access Journals (Sweden)

    Farinoosh Fakharnia

    2010-06-01

    Full Text Available Background and Aim: Balance disturbance is one of the non-auditory effects of noisy industrial environments that is usually neglected. The aim of the current study was to investigate the effect of occupational noise on vestibular system among workers with noise-induced hearing loss (NIHL, based on both vestibular evoked myogenic potentials (VEMP and caloric tests.Methods: Thirty male workers with noise-induced hearing loss and thirty male matched controls were examined by VEMP and caloric tests. Study parameters included unilateral weakness, p13 and n23 latencies, and p13-n23 amplitude. Caloric test was performed only for 20 patients.Results: No significant difference was observed in unilateral weakness between the two groups. On the other hand, the difference in mean latencies of p13 in the right ear (p=0.003 and left ear (p=0.01 was significant between the two groups. However, the difference in n23 latency was significant only in the right ear (p=0.03. There was no significant difference between groups in p13-n23 amplitude.Conclusion: It seems that pars inferior of vestibule is the susceptible part in individuals with NIHL. In general, abnormal findings in both VEMP and caloric tests were more common compared to functional symptoms such as vertigo, which may be due to central compensation and the symmetry of the disorder.

  5. Caloric test and video-head-impulse: a study of vertigo/dizziness patients in a community hospital.

    Science.gov (United States)

    Mahringer, Andrea; Rambold, Holger A

    2014-03-01

    The head-impulse test (HIT) is an important test for examining unilateral vestibular hypofunction. The new video-head-impulse test (vHIT) is more sensitive and specific than the clinical bedside-head-impulse test (bHIT). Alternatively, one can test for vestibular hypofunction with the caloric irrigation test. Various studies showed that both tests may not always identify vestibular hypofunction; instead, the results of the tests might be contradictory. To evaluate the diagnostic value of these tests, we routinely measured patients exhibiting vertigo or dizziness at our community hospital with bithermal caloric irrigation, the bHIT and the vHIT. Only those patients (n = 172) with a pathological caloric irrigation test of more than 25 % unilateral weakness in the Jongkee's formula were included. Out of these patients, 41 % had a pathologic vHIT. Among the subgroup with acute symptoms (symptom onset within 5 days), 63 % had a pathological video-head-impulse, whereas only 33 % of the non-acute group (symptom onset more than 5 days) tested pathological. A pathological HIT depended on the disease stage, the amount of unilateral weakness in caloric examination and on the test itself.

  6. Amorphization Induced High Magneto-Caloric Effect of Gd55A120Ni25 Ternary Alloy

    Institute of Scientific and Technical Information of China (English)

    DING Ding; XIA Lei; YU Zhong-Hua; DONG Yuan-Da

    2008-01-01

    We report the amorphization induced high magneto-caloric effect (MCE) of recently developed Gd55Al15Ni30 bulk metallic glass (BMG). The magnetic properties of the Gd55Al15Ni30 BMG are investigated in comparison with that of its crystalline counterpart. It is found that amorphization can increase the saturation magnetization and decrease the hysteresis of Gd55Al15Ni30 alloys, which indicate the possible enhancement of MCE. The magnetic entropy changes and the refrigerant capacity of the BMG as well as the crystalline samples is calculated directly from isothermal magnetic measurements. The results show the amorphization induced high MCE of the alloy and the excellent refrigerant efficiency of Gd55A115Ni30 bulk metallic glass.

  7. Caloric restriction suppresses apoptotic cell death in the mammalian cochlea and leads to prevention of presbycusis.

    Science.gov (United States)

    Someya, Shinichi; Yamasoba, Tatsuya; Weindruch, Richard; Prolla, Tomas A; Tanokura, Masaru

    2007-10-01

    Presbycusis is characterized by an age-related progressive decline of auditory function, and arises mainly from the degeneration of hair cells or spiral ganglion (SG) cells in the cochlea. Here we show that caloric restriction suppresses apoptotic cell death in the mouse cochlea and prevents late onset of presbycusis. Calorie restricted (CR) mice, which maintained body weight at the same level as that of young control (YC) mice, retained normal hearing and showed no cochlear degeneration. CR mice also showed a significant reduction in the number of TUNEL-positive cells and cleaved caspase-3-positive cells relative to middle-age control (MC) mice. Microarray analysis revealed that CR down-regulated the expression of 24 apoptotic genes, including Bak and Bim. Taken together, our findings suggest that loss of critical cells through apoptosis is an important mechanism of presbycusis in mammals, and that CR can retard this process by suppressing apoptosis in the inner ear tissue.

  8. Achieving tailorable magneto-caloric effect in the Gd-Co binary amorphous alloys

    Directory of Open Access Journals (Sweden)

    C. Wu

    2016-03-01

    Full Text Available Tailorable magnetic properties and magneto-caloric effect were achieved in the Gd-Co binary amorphous alloys. It was found that the Curie temperature (Tc of the GdxCo100-x (x=50, 53, 56, 58, 60 metallic glasses can be tuned by changing the concentration of Gd as Tc =708.8-8.83x, and the mechanism involved was investigated. On the other hand, a linear correlation between the peak value of magnetic entropy change (-Δ Smpeak and Tc-2/3 is found in the amorphous alloys with a linear correlation coefficients of above 0.992. Therefore, the -ΔSmpeak of the Gd-Co binary amorphous alloys under different magnetic fields can be easily tailored by adjusting the composition of the alloy.

  9. Hypophosphatemia and neurological changes secondary to oral caloric intake: a variant of hyperalimentation syndrome.

    Science.gov (United States)

    Silvis, S E; DiBartolomeo, A G; Aaker, H M

    1980-03-01

    Previous reports have described a syndrome of paresthesias, weakness, seizures and hypophosphatemia in patients and animals receiving intravenous hyperalimentation. In this report we describe a group of five patients who developed this syndrome while on oral caloric intake and three patients who received only modest amounts of hyperalimentation therapy. As an experimental corollary, studies were performed in starved and normal dogs with calories infused via an intragastric catheter. The serum inorganic phosphorus (Pi) fell slightly in normal animals from 4.8-2.5 mg. %. In the starved dogs with diarrhea or vomiting the Pi fell gradually from 4.8-1.6. In starved dogs without gastrointestinal symptoms the Pi fell precipitously from 3.7-1.4 mg % on the first day of infusion and remained at that level. Approximately 50% of the starved animals developed the neurological syndrome; none of the normal animals had neurological symptoms.

  10. Using Light Charged Particles to Probe the Asymmetry Dependence of the Nuclear Caloric Curve

    CERN Document Server

    McIntosh, Alan B; Kohley, Zachary; Cammarata, Paul J; Hagel, Kris; Heilborn, Lauren; Mabiala, Justin; May, Larry W; Marini, Paola; Raphelt, Andrew; Souliotis, George A; Wuenschel, Sara; Zarrella, Andrew; Yennello, Sherry J

    2013-01-01

    Recently, we observed a clear dependence of the nuclear caloric curve on neutron-proton asymmetry $\\frac{N-Z}{A}$ through examination of fully reconstructed equilibrated quasi-projectile sources produced in heavy ion collisions at E/A = 35 MeV. In the present work, we extend our analysis using multiple light charged particle probes of the temperature. Temperatures are extracted with five distinct probes using a kinetic thermometer approach. Additionally, temperatures are extracted using two probes within a chemical thermometer approach (Albergo method). All seven measurements show a significant linear dependence of the source temperature on the source asymmetry. For the kinetic thermometer, the strength of the asymmetry dependence varies with the probe particle species in a way which is consistent with an average emission-time ordering.

  11. Chaos theory applied to the caloric response of the vestibular system.

    Science.gov (United States)

    Aasen, T

    1993-12-01

    Developments in the field of nonlinear dynamics has given us a new conceptual framework for understanding the mechanisms involved in the regulation of complex nonlinear systems. This concept, called "chaos" or "deterministic chaos," has been applied to EKG, EEG, and other physiological signals, but not yet to the ENG signal. The underlying geometrical structure in chaotic dynamics is fractal (noninteger dimension), and calculating the fractal dimension of the electronystagmographic recording from caloric testing gave a dimension ranging from 3.3 to 7.7. This result demonstrates that the multidimensional vestibular system, with its numerous neurological pathways, can somehow reduce the degrees of freedom and give rise to an irregular dynamic low-dimensional behavior, which is associated with deterministic chaos.

  12. Repletion of TNFα or leptin in calorically restricted mice suppresses post-restriction hyperphagia

    Science.gov (United States)

    Hambly, Catherine; Duncan, Jacqueline S.; Archer, Zoë A.; Moar, Kim M.; Mercer, Julian G.; Speakman, John R.

    2012-01-01

    SUMMARY The causes of post-restriction hyperphagia (PRH) represent a target for drug-based therapies to prevent obesity. However, the factors causing PRH are poorly understood. We show that, in mice, the extent of PRH was independent of the time under restriction, but depended on its severity, suggesting that PRH was driven by signals from altered body composition. Signals related to fat mass were important drivers. Circulating levels of leptin and TNFα were significantly depleted following caloric restriction (CR). We experimentally repleted their levels to match those of controls, and found that in both treatment groups the level of PRH was significantly blunted. These data establish a role for TNFα and leptin in the non-pathological regulation of energy homeostasis. Signals from adipose tissue, including but not limited to leptin and TNFα, regulate PRH and might be targets for therapies that support people engaged in CR to reduce obesity. PMID:21954068

  13. The effect of non-caloric sweeteners on cognition, choice, and post-consumption satisfaction.

    Science.gov (United States)

    Hill, Sarah E; Prokosch, Marjorie L; Morin, Amanda; Rodeheffer, Christopher D

    2014-12-01

    Consumers often turn to non-caloric sweeteners (NCS) as a means of promoting a healthy body weight. However, several studies have now linked their long-term use to increased weight gain, raising the question of whether these products produce unintended psychological, physiological, or behavioral changes that have implications for weight management goals. In the following, we present the results of three experiments bearing on this issue, testing whether NCS-consumption influences how individuals think about and respond to food. Participants in each of our three experiments were randomly assigned to consume a sugar-sweetened beverage, an unsweetened beverage, or a beverage sweetened with NCS. We then measured their cognition (Experiment 1), product choice (Experiment 2), and subjective responses to a sugar-sweetened food (Experiment 3). Results revealed that consuming NCS-sweetened beverages influences psychological processes in ways that - over time - may increase calorie intake.

  14. A Magnetically Responsive Polydiacetylene Precursor for Latent Fingerprint Analysis.

    Science.gov (United States)

    Lee, Joosub; Lee, Chan Woo; Kim, Jong-Man

    2016-03-01

    A magnetically responsive diacetylene (DA) powder was developed for the visualization of latent fingerprints. A mixture of the DA and magnetite nanoparticles, applied to a surface containing latent fingermarks, becomes immobilized along the ridge patterns of the fingerprints when a magnetic field is applied. Alignment along the ridge structures is a consequence of favorable hydrophobic interactions occurring between the long alkyl chains in the DAs and the lipid-rich, sebaceous latent fingermarks. UV irradiation of the DA-magnetite composite immobilized on the latent fingerprint results in the generation of blue-colored PDAs. Heat treatment of the blue-colored image promotes a blue-to-red transition as well as fluorescence turn-on. A combination of the aligned pale brown-colored monomeric state, UV irradiation generated blue-colored PDA state, as well as the heat treatment generated red-colored and fluorescent PDA state enables efficient visual imaging of a latent fingerprint, which is deposited on various colored solid surfaces.

  15. Latent lip print development and its role in suspect identification

    Directory of Open Access Journals (Sweden)

    Nidhi Dwivedi

    2013-01-01

    Full Text Available Aims and Objective: The study aims to develop latent lip prints on glass surface using fingerprint black powder and its comparison with standard lipstick prints and also determines the effectiveness of the technique. Materials and Methods: This study included a total of 100 subjects, comprising of 50 males and 50 females with age ranging from 17 to 38 years. Latent lipprint was developed by pressing the lips against a glass slab with lips together and the print formed was developed by sprinkling the black finger print powder and transferred to a bond sheet. Subsequently, standard lipstick print was developed from the same subject. All the samples were coded and graded according to the patterns suggested in the literature. Results: Out of 100 latent prints only 29 prints showed lip patterns in all four quadrants. The percentage matching with self lipstick print of good latent prints ranged from 25% to 100% and those of random prints ranged from 8% to 92%. Quadrant wise matching ranged from 52.67% to 57.67%. Statistically significant difference was observed between males and females. Conclusion: The study demonstrates the usefulness of latent lip print in personal identification.

  16. Learning From Hidden Traits: Joint Factor Analysis and Latent Clustering

    Science.gov (United States)

    Yang, Bo; Fu, Xiao; Sidiropoulos, Nicholas D.

    2017-01-01

    Dimensionality reduction techniques play an essential role in data analytics, signal processing and machine learning. Dimensionality reduction is usually performed in a preprocessing stage that is separate from subsequent data analysis, such as clustering or classification. Finding reduced-dimension representations that are well-suited for the intended task is more appealing. This paper proposes a joint factor analysis and latent clustering framework, which aims at learning cluster-aware low-dimensional representations of matrix and tensor data. The proposed approach leverages matrix and tensor factorization models that produce essentially unique latent representations of the data to unravel latent cluster structure -- which is otherwise obscured because of the freedom to apply an oblique transformation in latent space. At the same time, latent cluster structure is used as prior information to enhance the performance of factorization. Specific contributions include several custom-built problem formulations, corresponding algorithms, and discussion of associated convergence properties. Besides extensive simulations, real-world datasets such as Reuters document data and MNIST image data are also employed to showcase the effectiveness of the proposed approaches.

  17. Regression of latent endometrial precancers by progestin infiltrated intrauterine device.

    Science.gov (United States)

    Ørbo, Anne; Rise, Cecil E; Mutter, George L

    2006-06-01

    PTEN tumor suppressor inactivation is the earliest step in endometrial carcinogenesis, occurring in morphologically unremarkable endometrial glands in half of normal women. We test the hypothesis that sex hormones positively or negatively select for these "latent precancers" by examining their emergence, persistence, and regression rates under differing hormonal conditions. Perimenopausal and postmenopausal women had an intake endometrial biopsy and underwent hormonal therapy with progestin-impregnated intrauterine device (IUD; n = 21), cyclic oral progestins (n = 28), or surveillance only (n = 22) with follow-up biopsies. For comparison, premenopausal naturally cycling endometrial biopsies were studied as single time points in 87 patients and multiple surveillance time points in 34 patients. Biopsies in which any PTEN protein-null glands were found by immunohistochemistry were scored as containing a latent endometrial precancer. All groups had a similar proportion of latent precancers at intake but differed after therapy. Emergence rates were highest (21%) for the naturally cycling premenopausal group compared with just 9% for untreated perimenopausal women. The IUD group had the highest rate of regression, with a 62% pretherapy and 5% post-therapy rate of latent precancers. This contrasted to nonsignificant changes for the oral progestin and untreated control groups. Delivery of high doses of progestins locally to the endometrium by IUD leads to ablation of preexisting PTEN-inactivated endometrial latent precancers and is a possible mechanism for reduction of long-term endometrial cancer risk known to occur in response to this hormone.

  18. Some properties of active and latent catechol oxidase of mushroom

    Directory of Open Access Journals (Sweden)

    Janusz Czapski

    2013-12-01

    Full Text Available Latent form of mushroom catechol oxidase was activated by O,1% sodium dodecyl sulfate (SDS. Catalytic power of the latent form, calculated from the kinetic parameters was 1,8 times higher than that of active one. Salicyl hydroxamic acid (SHAM appeared as a powerful inhibitor for both active and latent forms of catechol oxidase. However, in the range of 150-250 μM SHAM the inhibitory effect for active catechol oxidase was significantly higher than that for the latent one. Non-competitive and irreversible characteristics of inhibition of latent and active catechol oxidase was calculated from kinetic data. Electrophoretic analysis followed by scanning of the gels was used. The spots' absorbance was determined from a computer image of the isoenzyme band patterns. It allowed us to estimate gels quantitatively. Presence of one additional clearly defined slow moving isoform of SDS-activated catechol oxidase, differed in the respect of 3 bands for the active and 4 bands for the total.

  19. Higher Caloric Refeeding Is Safe in Hospitalised Adolescent Patients with Restrictive Eating Disorders

    Directory of Open Access Journals (Sweden)

    Elizabeth K. Parker

    2016-01-01

    Full Text Available Introduction. This study examines weight gain and assesses complications associated with refeeding hospitalised adolescents with restrictive eating disorders (EDs prescribed initial calories above current recommendations. Methods. Patients admitted to an adolescent ED structured “rapid refeeding” program for >48 hours and receiving ≥2400 kcal/day were included in a 3-year retrospective chart review. Results. The mean (SD age of the 162 adolescents was 16.7 years (0.9, admission % median BMI was 80.1% (10.2, and discharge % median BMI was 93.1% (7.0. The mean (SD starting caloric intake was 2611.7 kcal/day (261.5 equating to 58.4 kcal/kg (10.2. Most patients (92.6% were treated with nasogastric tube feeding. The mean (SD length of stay was 3.6 weeks (1.9, and average weekly weight gain was 2.1 kg (0.8. No patients developed cardiac signs of RFS or delirium; complications included 4% peripheral oedema, 1% hypophosphatemia (<0.75 mmol/L, 7% hypomagnesaemia (<0.70 mmol/L, and 2% hypokalaemia (<3.2 mmol/L. Caloric prescription on admission was associated with developing oedema (95% CI 1.001 to 1.047; p=0.039. No statistical significance was found between electrolytes and calories provided during refeeding. Conclusion. A rapid refeeding protocol with the inclusion of phosphate supplementation can safely achieve rapid weight restoration without increased complications associated with refeeding syndrome.

  20. The Impact of Exercise Training Compared to Caloric Restriction on Hepatic and Peripheral Insulin Resistance in Obesity

    Science.gov (United States)

    Coker, Robert H.; Williams, Rick H.; Yeo, Sophie E.; Kortebein, Patrick M.; Bodenner, Don L.; Kern, Philip A.; Evans, William J.

    2009-01-01

    Context: It has been difficult to distinguish the independent effects of caloric restriction versus exercise training on insulin resistance. Objective: Utilizing metabolic feeding and supervised exercise training, we examined the influence of caloric restriction vs. exercise training with and without weight loss on hepatic and peripheral insulin resistance. Design, Participants, and Intervention: Thirty-four obese, older subjects were randomized to: caloric restriction with weight loss (CR), exercise training with weight loss (EWL), exercise training without weight loss (EX), or controls. Based on an equivalent caloric deficit in EWL and CR, we induced matched weight loss. Subjects in the EX group received caloric compensation. Combined with [6,62H2]glucose, an octreotide, glucagon, multistage insulin infusion was performed to determine suppression of glucose production (SGP) and insulin-stimulated glucose disposal (ISGD). Computed tomography scans were performed to assess changes in fat distribution. Results: Body weight decreased similarly in EWL and CR, and did not change in EX and controls. The reduction in visceral fat was significantly greater in EWL (−71 ± 15 cm2) compared to CR and EX. The increase in SGP was also almost 3-fold greater (27 ± 2%) in EWL. EWL and CR promoted similar improvements in ISGD [+2.5 ± 0.4 and 2.4 ± 0.9 mg · kg fat-free mass (FFM)−1 · min−1], respectively. Conclusions: EWL promoted the most significant reduction in visceral fat and the greatest improvement in SGP. Equivalent increases in ISGD were noted in EWL and CR, whereas EX provided a modest improvement. Based on our results, EWL promoted the optimal intervention-based changes in body fat distribution and systemic insulin resistance. PMID:19808853

  1. Isotermas de dessorção e calor isostérico dos frutos de crambe Desorption isotherms and isosteric heat of the fruits of crambe

    Directory of Open Access Journals (Sweden)

    Lílian M. Costa

    2013-04-01

    Full Text Available Neste trabalho objetivou-se determinar as isotermas de sorção dos frutos de crambe e obter os valores do calor isostérico de dessorção em função do teor de água de equilíbrio. Para obtenção do teor de água de equilíbrio higroscópico utilizaram-se os frutos de crambe com teor de água inicial de 26,0 (% base seca e o método estático-gravimétrico e, para cada repetição, foram colocados 10 g de frutos envolvidos por um tecido permeável para permitir o contato do ar com o produto e colocados no interior dos dessecadores enquanto para o controle da umidade relativa no interior dos dessecadores foram utilizadas soluções saturadas. Os dessecadores foram colocados em câmara incubadora tipo B.O.D. regulada para as temperaturas de 25, 30, 35 e 40 °C. O teor de água de equilíbrio higroscópico dos frutos de crambe é diretamente proporcional à atividade de água e decresce com o aumento de temperatura, para um mesmo valor de umidade relativa de equilíbrio. Baseando-se em parâmetros estatísticos os modelos de Copace e Oswin Modificado são os que melhor representam a higroscopicidade dos frutos de crambe quando comparados com os demais modelos testados. O calor isostérico aumenta com a diminuição do teor de água de equilíbrio sendo necessária uma quantidade maior de energia para retirar a água dos frutos de crambe.This study aimed to adjust different mathematical models to experimental data of hygroscopicity of crambe fruits, selecting one that best represented the phenomenon, and obtain the values of the isosteric heat of desorption as a function of equilibrium moisture content. To obtain an equilibrium moisture content, crambe fruit was used with an initial moisture content of 26.0% (dry basis and static gravimetric method. For each replicate 10 g of fruit were placed surrounded by a permeable fabric to permit air contact with the product and placed within the desiccators. To control the relative humidity inside the

  2. Use of fluorescence lifetime imaging (FLIM) for latent fingerprints detection

    Science.gov (United States)

    Wang, Peng; Chao, Zhi Xia; Seah, Leong K.; Murukeshan, Vadakke M.

    2005-04-01

    Fluorescence lifetime imaging (FLIM) in frequency domain enables the mapping of the spatial distribution of fluorescence lifetimes of a specimen. FLIM can provide unique information about fluorophores and hence is widely used in biology and for medical diagnostics. In this paper, a theoretical analysis for the fluorescence lifetime determination of latent fingerprint samples is described, which is followed by the feasibility study of using FLIM in frequency domain for latent fingerprints detection. Experiments are carried out with fingerprint on green paper substrate and postcard substrate treated with certain fluorescent powder. The total phase lag and demodulation factor are calculated to determine the lifetimes pixel by pixel. The resulting fluorescence lifetime image of fingerprint revealed an improvement in the contrast, and was able to detect the latent fingerprint clearly.

  3. Latent Fundamentals Arbitrage with a Mixed Effects Factor Model

    Directory of Open Access Journals (Sweden)

    Andrei Salem Gonçalves

    2012-09-01

    Full Text Available We propose a single-factor mixed effects panel data model to create an arbitrage portfolio that identifies differences in firm-level latent fundamentals. Furthermore, we show that even though the characteristics that affect returns are unknown variables, it is possible to identify the strength of the combination of these latent fundamentals for each stock by following a simple approach using historical data. As a result, a trading strategy that bought the stocks with the best fundamentals (strong fundamentals portfolio and sold the stocks with the worst ones (weak fundamentals portfolio realized significant risk-adjusted returns in the U.S. market for the period between July 1986 and June 2008. To ensure robustness, we performed sub period and seasonal analyses and adjusted for trading costs and we found further empirical evidence that using a simple investment rule, that identified these latent fundamentals from the structure of past returns, can lead to profit.

  4. Classification criteria of syndromes by latent variable models

    DEFF Research Database (Denmark)

    Petersen, Janne

    2010-01-01

    The thesis has two parts; one clinical part: studying the dimensions of human immunodeficiency virus associated lipodystrophy syndrome (HALS) by latent class models, and a more statistical part: investigating how to predict scores of latent variables so these can be used in subsequent regression...... analyses. Part 1: HALS engages different phenotypic changes of peripheral lipoatrophy and central lipohypertrophy.  There are several different definitions of HALS and no consensus on the number of phenotypes. Many of the definitions consist of counting fulfilled criteria on markers and do not include...... patient's characteristics. These methods may erroneously reduce multiplicity either by combining markers of different phenotypes or by mixing HALS with other processes such as aging. Latent class models identify homogenous groups of patients based on sets of variables, for example symptoms. As no gold...

  5. Current management options for latent tuberculosis: a review

    Directory of Open Access Journals (Sweden)

    Norton BL

    2012-11-01

    Full Text Available Brianna L Norton, David P HollandDepartment of Medicine, Division of Infectious Diseases, Duke University Medical Center, Durham, NC, USAAbstract: Tuberculosis remains the world’s second leading infectious cause of death, with nearly one-third of the global population latently infected. Treatment of latent tuberculosis infection is a mainstay of tuberculosis-control efforts in low-to medium-incidence countries. Isoniazid monotherapy has been the standard of care for decades, but its utility is impaired by poor completion rates. However, new, shorter-course regimens using rifamycins improve completion rates and are cost-saving compared with standard isoniazid monotherapy. We review the currently available therapies for latent tuberculosis infection and their toxicities and include a brief economic comparison of the different regimens.Keywords: isoniazid, rifampin, rifapentine, tuberculin skin test, interferon-gamma release assay

  6. Cosine Based Latent Factor Model for Precision Oriented Recommendation

    Directory of Open Access Journals (Sweden)

    Bipul Kumar

    2016-01-01

    Full Text Available Recommender systems suggest a list of interesting items to users based on their prior purchase or browsing behaviour on e-commerce platforms. The continuing research in recommender systems have primarily focused on developing algorithms for rating prediction task. However, most e-commerce platforms provide ‘top-k’ list of interesting items for every user. In line with this idea, the paper proposes a novel machine learning algorithm to predict a list of ‘top-k’ items by optimizing the latent factors of users and items with the mapped scores from ratings. The basic idea is to learn latent factors based on the cosine similarity between the users and items latent features which is then used to predict the scores for unseen items for every user. Comprehensive empirical evaluations on publicly available benchmark datasets reveal that the proposed model outperforms the state-of-the-art algorithms in recommending good items to a user.

  7. Latent Tuberculosis in Pregnancy: A Systematic Review.

    Directory of Open Access Journals (Sweden)

    Isabelle Malhamé

    Full Text Available In countries with low tuberculosis (TB incidence, immigrants from higher incidence countries represent the major pool of individuals with latent TB infection (LTBI. The antenatal period represents an opportunity for immigrant women to access the medical system, and hence for potential screening and treatment of LTBI. However, such screening and treatment during pregnancy remains controversial.In order to further understand the prevalence, natural history, screening and management of LTBI in pregnancy, we conducted a systematic literature review addressing the screening and treatment of LTBI, in pregnant women without known HIV infection.A systematic review of 4 databases (Embase, Embase Classic, Medline, Cochrane Library covering articles published from January 1st 1980 to April 30th 2014. Articles in English, French or Spanish with relevant information on prevalence, natural history, screening tools, screening strategies and treatment of LTBI during pregnancy were eligible for inclusion. Articles were excluded if (1 Full text was not available (2 they were case series or case studies (3 they focused exclusively on prevalence, diagnosis and treatment of active TB (4 the study population was exclusively HIV-infected.Of 4,193 titles initially identified, 208 abstracts were eligible for review. Of these, 30 articles qualified for full text review and 22 were retained: 3 cohort studies, 2 case-control studies, and 17 cross-sectional studies. In the USA, the estimated prevalence of LTBI ranged from 14 to 48% in women tested, and tuberculin skin test (TST positivity was associated with ethnicity. One study suggested that incidence of active TB was significantly increased during the 180 days postpartum (Incidence rate ratio, 1.95 (95% CI 1.24-3.07. There was a high level of adherence with both skin testing (between 90-100% and chest radiography (93-100%.. In three studies from low incidence settings, concordance between TST and an interferon

  8. Treatment guidelines for latent tuberculosis infection.

    Science.gov (United States)

    2014-01-01

    The treatment of latent tuberculosis infection (LTBI) has been established as valid for patients at high risk for developing active tuberculosis. Treatment of LTBI is also considered an important strategy for eliminating tuberculosis (TB) in Japan. In recent years, interferon-gamma release assays have come into widespread use; isoniazid (INH) preventive therapy for HIV patients has come to be recommended worldwide; and there have been increases in both types of biologics used in the treatment of immune diseases as well as the diseases susceptible to treatment. In light of the above facts, the Prevention Committee and the Treatment Committee of the Japanese Society for Tuberculosis have jointly drafted these guidelines. In determining subjects for LTBI treatment, the following must be considered: 1) risk of TB infection/ development; 2) infection diagnosis; 3) chest image diagnosis; 4) the impact of TB development; 5) the possible manifestation of side effects; and 6) the prospects of treatment completion. LTBI treatment is actively considered when relative risk is deemed 4 or higher, including risk factors such as the following: HIV/AIDS, organ transplants (immunosuppressant use), silicosis, dialysis due to chronic renal failure, recent TB infection (within 2 years), fibronodular shadows in chest radiographs (untreated old TB), the use of biologics, and large doses of corticosteroids. Although the risk is lower, the following risk factors require consideration of LTBI treatment when 2 or more of them are present: use of oral or inhaled corticosteroids, use of other immunosuppressants, diabetes, being underweight, smoking, gastrectomy, and so on. In principle, INH is administered for a period of 6 or 9 months. When INH cannot be used, rifampicin is administered for a period of 4 or 6 months. It is believed that there are no reasons to support long-term LTBI treatment for immunosuppressed patients in Japan, where the risk of infection is not considered markedly high

  9. Design and simulation of latent heat storage units. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Shamsundar, N.; Stein, E.; Rooz, E.; Bascaran, E.; Lee, T.C. [Houston Univ., TX (United States)

    1992-04-01

    This report presents the results of two years of research and development on passive latent heat storage systems. Analytical models have been developed and extended, and a computer code for simulating the performance of a latent heat storage has been developed. The code is intended to be merged into a larger solar energy system simulation code and used for making realistic system studies. Simulation studies using a code which has a flexible and accurate routine for handling the storage subsystem should lead to the development of better systems than those in which storage is added on after the rest of the system has already been selected and optimized.

  10. Design and simulation of latent heat storage units

    Energy Technology Data Exchange (ETDEWEB)

    Shamsundar, N.; Stein, E.; Rooz, E.; Bascaran, E.; Lee, T.C. (Houston Univ., TX (United States))

    1992-04-01

    This report presents the results of two years of research and development on passive latent heat storage systems. Analytical models have been developed and extended, and a computer code for simulating the performance of a latent heat storage has been developed. The code is intended to be merged into a larger solar energy system simulation code and used for making realistic system studies. Simulation studies using a code which has a flexible and accurate routine for handling the storage subsystem should lead to the development of better systems than those in which storage is added on after the rest of the system has already been selected and optimized.

  11. Chromatin Structure of Epstein-Barr Virus Latent Episomes.

    Science.gov (United States)

    Lieberman, Paul M

    2015-01-01

    EBV latent infection is characterized by a highly restricted pattern of viral gene expression. EBV can establish latent infections in multiple different tissue types with remarkable variation and plasticity in viral transcription and replication. During latency, the viral genome persists as a multi-copy episome, a non-integrated-closed circular DNA with nucleosome structure similar to cellular chromosomes. Chromatin assembly and histone modifications contribute to the regulation of viral gene expression, DNA replication, and episome persistence during latency. This review focuses on how EBV latency is regulated by chromatin and its associated processes.

  12. Powder method for detecting latent fingerprints: a review.

    Science.gov (United States)

    Sodhi, G S; Kaur, J

    2001-09-01

    The powder technique for detecting latent fingerprints involves the application of a finely divided formulation to the fingermark impression, generally with a glass-fibre or a camel hair brush. The powder gets mechanically adhered to the sweat residue defining the ridge pattern. The furrows which are devoid of the fingerprint residue, do not adhere the powder onto them. The final outcome is that the powder formulation sticks to the ridges, but is easily blown off the furrows. Since the powder is normally coloured, the ridge pattern becomes visible and the latent print is said to have developed.

  13. Latent common manifold learning with alternating diffusion: analysis and applications

    CERN Document Server

    Talmon, Ronen

    2016-01-01

    The analysis of data sets arising from multiple sensors has drawn significant research attention over the years. Traditional methods, including kernel-based methods, are typically incapable of capturing nonlinear geometric structures. We introduce a latent common manifold model underlying multiple sensor observations for the purpose of multimodal data fusion. A method based on alternating diffusion is presented and analyzed; we provide theoretical analysis of the method under the latent common manifold model. To exemplify the power of the proposed framework, experimental results in several applications are reported.

  14. Hippocampus NMDA receptors selectively mediate latent extinction of place learning.

    Science.gov (United States)

    Goodman, Jarid; Gabriele, Amanda; Packard, Mark G

    2016-09-01

    Extinction of maze learning may be achieved with or without the animal performing the previously acquired response. In typical "response extinction," animals are given the opportunity to make the previously acquired approach response toward the goal location of the maze without reinforcement. In "latent extinction," animals are not given the opportunity to make the previously acquired response and instead are confined to the previous goal location without reinforcement. Previous evidence indicates that the effectiveness of these protocols may depend on the type of memory being extinguished. Thus, one aim of the present study was to further examine the effectiveness of response and latent extinction protocols across dorsolateral striatum (DLS)-dependent response learning and hippocampus-dependent place learning tasks. In addition, previous neural inactivation experiments indicate a selective role for the hippocampus in latent extinction, but have not investigated the precise neurotransmitter mechanisms involved. Thus, the present study also examined whether latent extinction of place learning might depend on NMDA receptor activity in the hippocampus. In experiment 1, adult male Long-Evans rats were trained in a response learning task in a water plus-maze, in which animals were reinforced to make a consistent body-turn response to reach an invisible escape platform. Results indicated that response extinction, but not latent extinction, was effective at extinguishing memory in the response learning task. In experiment 2, rats were trained in a place learning task, in which animals were reinforced to approach a consistent spatial location containing the hidden escape platform. In experiment 2, animals also received intra-hippocampal infusions of the NMDA receptor antagonist 2-amino-5-phosphopentanoic acid (AP5; 5.0 or 7.5 ug/0.5 µg) or saline vehicle immediately before response or latent extinction training. Results indicated that both extinction protocols were

  15. ANTRACNOSE DO CAQUIZEIRO CAUSADA POR Colletotrichum horii: INCIDÊNCIA EM RAMOS, FOLHAS, FLORES E FRUTOS EM CAMPO

    Directory of Open Access Journals (Sweden)

    RENATO REZENDE YOUNG BLOOD

    2015-06-01

    Full Text Available O objetivo deste trabalho foi avaliar a incidência em várias partes da planta e o desenvolvimento da antracnose do caquizeiro causada por Colletotrichum horiinas cultivares Fuyu e Kakimel produzidas sob os sistemas orgânico e convencional, respectivamente, nas safras de 2010/2011 e 2011/2012, em Campina Grande do Sul, Paraná, Brasil. Em cada pomar, 10 plantas foram selecionadas aleatoriamente, e 10 ramos do ano por planta, distribuídos ao redor dacopa, foram marcados para as avaliações de incidência de antracnose em ramos e folhas, a cada 15 dias. A quantificação de frutos caídos com ou sem sintomas da doença foi a cada 15 dias, durante o período de crescimento de frutos até a colheita, relacionada com a produção total. C. horii em flores foi avaliada em campo e também após incubação no laboratório. Infecção latente foi observada em frutos verdes coletados aos 90; 120 e 150 dias após a floração. Em ambas as safras, observou-se a queda de frutos com sintomas de antracnose entre os meses de janeiro e abril. C. horii é capaz de infectar flores, permanecer latente e provocar sintomas de antracnose em frutos imaturos. Frutos colhidos sadios apresentaram sintomas em pós-colheita após a incubação.

  16. Interpretação e utilidade da prova calórica Interpretation and use of caloric testing

    Directory of Open Access Journals (Sweden)

    Denise Utsch Gonçalves

    2008-06-01

    Full Text Available A prova calórica é o teste da avaliação otoneurológica que verifica a integridade do reflexo vestíbulo-ocular e possibilita avaliar cada labirinto separadamente. Os principais aspectos relacionados à realização, interpretação e utilidade da prova calórica foram revistos. MÉTODOS: Realizou-se revisão sistemática sobre as publicações ocorridas nos últimos cem anos sobre o assunto. Incluíram-se artigos originais transversais e longitudinais, de revisão e meta-análise. Excluíram-se revisões de papeleta, relatos de caso e editoriais. Os descritores utilizados foram: prova calórica, nistagmo, sistema vestibular, preponderância direcional, predomínio labiríntico, teste calórico monotermal, teste calórico com água gelada, fenômeno de Bell. Pesquisou-se as bases de dados COCHRAINE, MEDLINE, LILACS, CAPES. RESULTADOS: De 818 resumos de artigos, selecionou-se inicialmente 93 que preenchiam os critérios de inclusão. A leitura dos artigos resultou na seleção final de 55. Na análise dos artigos, enfatizou-se na discussão fundamentos da prova calórica, tipos de estimulação utilizados, prova calórica monotermal e com água gelada, questões relacionadas à interpretação dos resultados, variáveis e artefatos. COMENTÁRIOS FINAIS: os valores de referência utilizados na prova calórica podem variar de serviço para serviço, com ponto de corte definido a partir de estudos locais. Semiotécnica cuidadosa é fundamental para elevar a sensibilidade do exame.Caloric testing is an otoneurologic evaluation of the status of the vestibular-ocular reflex; it allows an evaluation of each labyrinth separately. The main aspects on the use and interpretation of caloric testing are reviewed. METHOD: A systematic review of papers published in the past one hundred years on caloric testing was undertaken. The inclusion criteria were: cross-sectional, longitudinal, original articles, reviews and meta-analyses. Reviews of patient charts

  17. Función de Green para la ecuación hiperbólica de transmisión del calor.

    OpenAIRE

    2008-01-01

    En esta memoria se recoge fundamentalmente el estudio, bajo el punto de vista del modelo hiperbólico de transmisión del calor, de un problema de transmisión del calor basado en el procesado de materiales mediante pulsos de láser de alta intensidad y tiempos de aplicación muy cortos. Este tipo de problemas lleva asociado el desarrollo de un riguroso estudio matemático para la ecuación hiperbólica de transmisión del calor que nos permita establecer los fundamentos teóricos para el cálculo ...

  18. El golpe de calor en la actividad física y el deporte (versión traducida al español)

    OpenAIRE

    Hosokawa, Yuri; Adams, William M; Stearns, Rebecca L.; Casa, Douglas J.

    2014-01-01

    El golpe de calor por esfuerzo (GCE) es una de las causas principales de muerte súbita durante el deporte y la actividad física. Solamente en el fútbol americano han ocurrido 46 muertes documentadas en los EE.UU. entre 1995 y 2010. En el 2003, la asociación responsable por los deportes universitarios de los EE.UU. estableció pautas obligatorias de aclimatización al calor, las cuales tuvieron como resultado una disminución exitosa en el número de muertes por golpe de calor en ese deporte. Sin ...

  19. Percepción de sed e ingesta de líquido después del ejercicio en el calor

    OpenAIRE

    Aragón-Vargas, Luis Fernando; Capitán Jiménez, Catalina

    2016-01-01

    La sudoración durante el ejercicio en el calor puede producir una deshidratación importante que debe reponerse mediante la ingesta de líquido. Este estudio experimental evalúa la afirmación de que la ingesta voluntaria de agua, que supuestamente ocurre como respuesta a la sed, es suficiente para reponer el líquido perdido. 14 participantes realizaron ejercicio en dos ocasiones en un cuarto de clima controlado programado para calor seco (tbs = 33.8C, HR = 53%) y calor húmedo (tbs = 32.1C y H...

  20. Variação sazonal do fluxo de calor no solo dentro de um manguezal tropical Seazonal variation of soil heat flux within tropical mangrove

    Directory of Open Access Journals (Sweden)

    Marcos A. L. Moura

    2010-03-01

    Full Text Available Os manguezais são ecossistemas de grande importância em virtude da sua biodiversidade, embora ainda pouco estudados. O fluxo de calor no solo (FCS é uma propriedade que interfere no microclima de um ecossistema e depende de vários fatores. Um estudo experimental foi realizado em um manguezal no município de Marechal Deodoro, Alagoas, no período de outubro/2004 a outubro/2005, com o objetivo de caracterizar a variação sazonal do FCS; para isto, uma estação meteorológica automática foi montada em uma torre micrometeorológica para registrar diferentes elementos do tempo e clima, de forma contínua. Especificamente, para medição do FCS a 10 cm de profundidade utilizou-se uma bateria de três fluxímetros modelo HFT3 (Campbell Scientific, EUA no sentido de que a interferência da não uniformidade do solo nas medições fosse minimizada. Os resultados obtidos demonstraram influência da radiação solar, precipitação e da maré sobre a variação diária e sazonal do FCS, além de grande diferença de amplitude diária do FCS entre os períodos chuvoso (9 W m-2 e seco (36 W m-2.Mangrove swamps are highly important ecosystems due to their biodiversity, but they still are little studied. Soil heat fluxes (SHF is one of the proprieties that interfere in the ecosystem microclimate and depends on lots of factors. An experimental study was carried out in a mangrove forest in the Marechal Deodoro city, in the State of Alagoas, from October/2004 to October/2005, with the aim of describing the SHF seasonal variation. To this end, an automatic weather station was assembled in a micrometeorological tower to register the data continuously. To measure SHF in 10 cm depth one battery with three (3 fluximeter model HFT3 (Campbell Scientific, EUA was used so that the soil uniformity interference in the measurements was reduced. The obtained results showed influence of solar radiation, rainfall and tidal wave in the daily and seasonal SHF variation. A

  1. High Caloric Diet for ALS Patients: High Fat, High Carbohydrate or High Protein

    Directory of Open Access Journals (Sweden)

    Sarvin Sanaie

    2015-01-01

    . They showed that patients in the highcarbohydrate/high-calorie groups gained 0.39 kg more weight per month, compared with 0.11kg per month in the control group, and there was an average weight loss of 0.46 kg per month in the high-fat/high-calorie group. However, there are some concerns that highcarbohydrate low-fat diets might increase the risk of ALS and these findings should be interpreted with caution (4. Furthermore, according to Wills et al. high fat-high caloric diets could not be ideal regimens for these patients due to the associated gastrointestinal complications (3. Dorst and associates, in their study, showed that high caloric food supplement with high fat is suitable to establish body weight compared to high carbohydrate formula. Hence, it seems that high protein-high caloric diets could be more appropriate options for both improving negative nitrogen balance and decreasing muscle atrophy in patients with ALS based on the pathophysiology of proteinenergy malnutrition and hypermetabolism which is thought to be due to mitochondria problem. The multifactorial pathophysiology of ALS has resulted in hypotheses that there may be subgroups of patients, eventually defined by a specific underlying etiology or clinical presentation, which selectively respond to a particular regimen. Consequently, further RCTs with larger sample size are required to clarify the best regimen for weight gain and improved survival in ALS patients and it seems that personalized nutritional support or combined regimens might be the best way and could improve the quality of life considering the complex pathophysiology of malnutrition.

  2. Asymptotic accuracy of Bayesian estimation for a single latent variable.

    Science.gov (United States)

    Yamazaki, Keisuke

    2015-09-01

    In data science and machine learning, hierarchical parametric models, such as mixture models, are often used. They contain two kinds of variables: observable variables, which represent the parts of the data that can be directly measured, and latent variables, which represent the underlying processes that generate the data. Although there has been an increase in research on the estimation accuracy for observable variables, the theoretical analysis of estimating latent variables has not been thoroughly investigated. In a previous study, we determined the accuracy of a Bayes estimation for the joint probability of the latent variables in a dataset, and we proved that the Bayes method is asymptotically more accurate than the maximum-likelihood method. However, the accuracy of the Bayes estimation for a single latent variable remains unknown. In the present paper, we derive the asymptotic expansions of the error functions, which are defined by the Kullback-Leibler divergence, for two types of single-variable estimations when the statistical regularity is satisfied. Our results indicate that the accuracies of the Bayes and maximum-likelihood methods are asymptotically equivalent and clarify that the Bayes method is only advantageous for multivariable estimations.

  3. Immune parameters differentiating active from latent tuberculosis infection in humans.

    Science.gov (United States)

    Lee, Ji Yeon; Jung, Young Won; Jeong, Ina; Joh, Joon-Sung; Sim, Soo Yeon; Choi, Boram; Jee, Hyeon-Gun; Lim, Dong-Gyun

    2015-12-01

    Tuberculosis remains a highly prevalent infectious disease worldwide. Identification of the immune parameters that differentiate active disease from latent infection will facilitate the development of efficient control measures as well as new diagnostic modalities for tuberculosis. Here, we investigated the cytokine production profiles of monocytes and CD4(+) T lymphocytes upon encountering mycobacterial antigens. In addition, cytokines and lipid mediators with immune-modulating activities were examined in plasma samples ex vivo. Comparison of these parameters in active tuberculosis patients and healthy subjects with latent infection revealed that, active tuberculosis was associated with diminished Th1-type cytokine secretion from CD4(+) T cells and less augmented inflammatory cytokine secretion from monocytes induced by IFN-γ than that in latent tuberculosis infection. In addition, a higher plasma concentration of lipoxin A4 and lower ratio of prostaglandin E2 to lipoxin A4 were observed in active cases than in latent infections. These findings have implications for preparing new therapeutic strategies and for differential diagnosis of the two types of tuberculosis infection.

  4. Bayesian latent factor regression for functional and longitudinal data.

    Science.gov (United States)

    Montagna, Silvia; Tokdar, Surya T; Neelon, Brian; Dunson, David B

    2012-12-01

    In studies involving functional data, it is commonly of interest to model the impact of predictors on the distribution of the curves, allowing flexible effects on not only the mean curve but also the distribution about the mean. Characterizing the curve for each subject as a linear combination of a high-dimensional set of potential basis functions, we place a sparse latent factor regression model on the basis coefficients. We induce basis selection by choosing a shrinkage prior that allows many of the loadings to be close to zero. The number of latent factors is treated as unknown through a highly-efficient, adaptive-blocked Gibbs sampler. Predictors are included on the latent variables level, while allowing different predictors to impact different latent factors. This model induces a framework for functional response regression in which the distribution of the curves is allowed to change flexibly with predictors. The performance is assessed through simulation studies and the methods are applied to data on blood pressure trajectories during pregnancy.

  5. Removing systematic errors for exoplanet search via latent causes

    CERN Document Server

    Schölkopf, Bernhard; Wang, Dun; Foreman-Mackey, Daniel; Janzing, Dominik; Simon-Gabriel, Carl-Johann; Peters, Jonas

    2015-01-01

    We describe a method for removing the effect of confounders in order to reconstruct a latent quantity of interest. The method, referred to as half-sibling regression, is inspired by recent work in causal inference using additive noise models. We provide a theoretical justification and illustrate the potential of the method in a challenging astronomy application.

  6. Evaluation of AFIS-Ranked latent fingerprint matched templates

    NARCIS (Netherlands)

    Krish, Ram P.; Fierrez, Julian; Ramos, Daniel; Veldhuis, Raymond; Wang, Ruifang; Klette, Reinhard; Rivera, Mariano; Satoh, Shin'ichi

    2013-01-01

    The methodology currently practiced in latent print examination (known as ACE-V) yields only a decision as result, namely individualization, exclusion or inconclusive. From such a decision, it is not possible to express the strength of opinion of a forensic examiner quantitatively with a scientific

  7. A Taxometric Exploration of the Latent Structure of Hoarding

    Science.gov (United States)

    Timpano, Kiara R.; Broman-Fulks, Joshua J.; Glaesmer, Heide; Exner, Cornelia; Rief, Winfried; Olatunji, Bunmi O.; Keough, Meghan E.; Riccardi, Christina J.; Brahler, Elmar; Wilhelm, Sabine; Schmidt, Norman B.

    2013-01-01

    Despite controversy regarding the classification and diagnostic status of hoarding disorder, there remains a paucity of research on the nosology of hoarding that is likely to inform the classification debate. The present investigation examined the latent structure of hoarding in three, large independent samples. Data for three well-validated…

  8. Identifying subgroups of patients using latent class analysis

    DEFF Research Database (Denmark)

    Nielsen, Anne Mølgaard; Kent, Peter; Hestbæk, Lise

    2017-01-01

    BACKGROUND: Heterogeneity in patients with low back pain (LBP) is well recognised and different approaches to subgrouping have been proposed. Latent Class Analysis (LCA) is a statistical technique that is increasingly being used to identify subgroups based on patient characteristics. However, as ...

  9. Temporal analysis of text data using latent variable models

    DEFF Research Database (Denmark)

    Mølgaard, Lasse Lohilahti; Larsen, Jan; Goutte, Cyril

    2009-01-01

    Detecting and tracking of temporal data is an important task in multiple applications. In this paper we study temporal text mining methods for Music Information Retrieval. We compare two ways of detecting the temporal latent semantics of a corpus extracted from Wikipedia, using a stepwise...

  10. Complete genome sequence of the alfalfa latent virus

    Science.gov (United States)

    Alfalfa latent virus (ALV) is a member of the carlavirus group and occurs symptomlessly in alfalfa (Medicago sativa). In the US it is prevalent in Nebraska and Wisconsin. The virus is recognized as a strain of Pea streak virus (PeSV) So far, no complete genomic sequence of PSV or ALV is availab...

  11. Latent cluster analysis of ALS phenotypes identifies prognostically differing groups.

    Directory of Open Access Journals (Sweden)

    Jeban Ganesalingam

    Full Text Available BACKGROUND: Amyotrophic lateral sclerosis (ALS is a degenerative disease predominantly affecting motor neurons and manifesting as several different phenotypes. Whether these phenotypes correspond to different underlying disease processes is unknown. We used latent cluster analysis to identify groupings of clinical variables in an objective and unbiased way to improve phenotyping for clinical and research purposes. METHODS: Latent class cluster analysis was applied to a large database consisting of 1467 records of people with ALS, using discrete variables which can be readily determined at the first clinic appointment. The model was tested for clinical relevance by survival analysis of the phenotypic groupings using the Kaplan-Meier method. RESULTS: The best model generated five distinct phenotypic classes that strongly predicted survival (p<0.0001. Eight variables were used for the latent class analysis, but a good estimate of the classification could be obtained using just two variables: site of first symptoms (bulbar or limb and time from symptom onset to diagnosis (p<0.00001. CONCLUSION: The five phenotypic classes identified using latent cluster analysis can predict prognosis. They could be used to stratify patients recruited into clinical trials and generating more homogeneous disease groups for genetic, proteomic and risk factor research.

  12. Censored latent effects autoregression, with an application to US unemployment

    NARCIS (Netherlands)

    Ph.H.B.F. Franses (Philip Hans); R. Paap (Richard)

    1998-01-01

    textabstractA new time series model is proposed to describe observed asymmetries in postwar unemployment data. We assume that recession periods, when unemployment increases rapidly, are caused by unobserved positive shocks. The generating mechanism of these latent shocks is a censored regression mod

  13. Blueberry latent virus: An Amalgam of the Totiviridae and Partitiviridae

    Science.gov (United States)

    A new, symptomless virus was identified in blueberry. The dsRNA genome of the virus, provisionally named Blueberry latent virus (BBLV), codes for two putative proteins and lacks a movement protein, a property only shared with cryptic viruses. More than 35 isolates of the virus from different cultiv...

  14. Treatment: Latent TB Infection (LTBI) and TB Disease

    Science.gov (United States)

    ... the Facts Tuberculosis - The Connection between TB and HIV 12-Dose Regimen for Latent TB Infection-Patient Education Brochure Posters Mantoux Tuberculin Skin Test Wall Chart World TB Day Think TB Stop TB Reports & Articles Morbidity and Mortality Weekly Reports (MMWRs) DTBE Authored ...

  15. Improving Measurement Precision of Hierarchical Latent Traits Using Adaptive Testing

    Science.gov (United States)

    Wang, Chun

    2014-01-01

    Many latent traits in social sciences display a hierarchical structure, such as intelligence, cognitive ability, or personality. Usually a second-order factor is linearly related to a group of first-order factors (also called domain abilities in cognitive ability measures), and the first-order factors directly govern the actual item responses.…

  16. An Alternative Approach for Nonlinear Latent Variable Models

    Science.gov (United States)

    Mooijaart, Ab; Bentler, Peter M.

    2010-01-01

    In the last decades there has been an increasing interest in nonlinear latent variable models. Since the seminal paper of Kenny and Judd, several methods have been proposed for dealing with these kinds of models. This article introduces an alternative approach. The methodology involves fitting some third-order moments in addition to the means and…

  17. Exploring Different Types of Academic Delayers: A Latent Profile Analysis

    Science.gov (United States)

    Grunschel, Carola; Patrzek, Justine; Fries, Stefan

    2013-01-01

    In this study, we explored whether there are different types of academic delayers (i.e., types of students who delay academic tasks). Latent profile analysis based on 554 university students' reasons for academic delay revealed four distinct types: inconspicuous, successful pressure-seeking, worried/anxious, and discontent with studies. The types…

  18. Mediation Analysis in a Latent Growth Curve Modeling Framework

    Science.gov (United States)

    von Soest, Tilmann; Hagtvet, Knut A.

    2011-01-01

    This article presents several longitudinal mediation models in the framework of latent growth curve modeling and provides a detailed account of how such models can be constructed. Logical and statistical challenges that might arise when such analyses are conducted are also discussed. Specifically, we discuss how the initial status (intercept) and…

  19. Model Criticism of Bayesian Networks with Latent Variables.

    Science.gov (United States)

    Williamson, David M.; Mislevy, Robert J.; Almond, Russell G.

    This study investigated statistical methods for identifying errors in Bayesian networks (BN) with latent variables, as found in intelligent cognitive assessments. BN, commonly used in artificial intelligence systems, are promising mechanisms for scoring constructed-response examinations. The success of an intelligent assessment or tutoring system…

  20. Combining SNPs in latent variables to improve genomic prediction

    DEFF Research Database (Denmark)

    Heuven, Henri C M; Rosa, G J M; Janss, Luc

    The objective of this study was to develop and test hierarchical genomic models with latent variables that represent parts of the genomic values. An interaction model and a chromosome model were compared with a model based on variable selection in a simulated and real dataset. The program Bayz......: Hierarchical genetic model; Predictive value; Gibbs sampling; Variable selection....

  1. The relationship between cub and loglinear models with latent variables

    NARCIS (Netherlands)

    Oberski, D. L.; Vermunt, J. K.

    2015-01-01

    The "combination of uniform and shifted binomial"(cub) model is a distribution for ordinal variables that has received considerable recent attention and specialized development. This article notes that the cub model is a special case of the well-known loglinear latent class model, an observation tha

  2. Latent organizations in the film industry: contracts, rewards and resources

    NARCIS (Netherlands)

    Ebbers, J.J.; Wijnberg, N.M.

    2009-01-01

    The main aim of this article is to study the extent to which the project-based organization (PBO) and the latent organization determine the actual behavior of actors in a project-based industry and how this is mediated by the types of contracts and rewarding practices these organizational forms allo

  3. Multilevel Latent Class Analysis: Parametric and Nonparametric Models

    Science.gov (United States)

    Finch, W. Holmes; French, Brian F.

    2014-01-01

    Latent class analysis is an analytic technique often used in educational and psychological research to identify meaningful groups of individuals within a larger heterogeneous population based on a set of variables. This technique is flexible, encompassing not only a static set of variables but also longitudinal data in the form of growth mixture…

  4. Layout of a latent heat storage system with finned tubes

    Energy Technology Data Exchange (ETDEWEB)

    Wolff, D.

    1980-10-26

    The theoretical and experimental investigations show by the example of Glauber's salt in a finned-tube latent heat storage vessel how heat transfer and storage capacity at charging and discharging depend on the variables of geometry, temperature, time and on the composition of the storing medium. By vertical arrangement of transversely finned tubes the separation problems occurring with Glauber's salt are solved insofar as the technical utilization of the latent heat of conversion corresponding to the complete conversion during charging and discharging not being possible, no decrease, of the reduced storage capacity, however, is found even after very many charging/discharging cycles. For the heat transfer during discharging correlations can be given on the basis of a model concept, be means of which a heat transfer coefficient, varying during the discharging process, can be predicted almost for the total range of discharge as a function of geometry, temperature and state of discharge. On the basis of the simple working formula for the heat transfer coefficient at crystallization of a latent heat storing medium the dynamic behavior of a compact finned-tube storage vessel can be predicted by means of a computer code. These means allow to perform the thermal design of a compact latent heat storage facility according to given design criteria accounting for economic aspects.

  5. A Hierarchical Latent Stochastic Differential Equation Model for Affective Dynamics

    Science.gov (United States)

    Oravecz, Zita; Tuerlinckx, Francis; Vandekerckhove, Joachim

    2011-01-01

    In this article a continuous-time stochastic model (the Ornstein-Uhlenbeck process) is presented to model the perpetually altering states of the core affect, which is a 2-dimensional concept underlying all our affective experiences. The process model that we propose can account for the temporal changes in core affect on the latent level. The key…

  6. Changes in latent fingerprint examiners' markup between analysis and comparison.

    Science.gov (United States)

    Ulery, Bradford T; Hicklin, R Austin; Roberts, Maria Antonia; Buscaglia, JoAnn

    2015-02-01

    After the initial analysis of a latent print, an examiner will sometimes revise the assessment during comparison with an exemplar. Changes between analysis and comparison may indicate that the initial analysis of the latent was inadequate, or that confirmation bias may have affected the comparison. 170 volunteer latent print examiners, each randomly assigned 22 pairs of prints from a pool of 320 total pairs, provided detailed markup documenting their interpretations of the prints and the bases for their comparison conclusions. We describe changes in value assessments and markup of features and clarity. When examiners individualized, they almost always added or deleted minutiae (90.3% of individualizations); every examiner revised at least some markups. For inconclusive and exclusion determinations, changes were less common, and features were added more frequently when the image pair was mated (same source). Even when individualizations were based on eight or fewer corresponding minutiae, in most cases some of those minutiae had been added during comparison. One erroneous individualization was observed: the markup changes were notably extreme, and almost all of the corresponding minutiae had been added during comparison. Latents assessed to be of value for exclusion only (VEO) during analysis were often individualized when compared to a mated exemplar (26%); in our previous work, where examiners were not required to provide markup of features, VEO individualizations were much less common (1.8%).

  7. The Latent Structure of Psychopathy in Youth: A Taxometric Investigation

    Science.gov (United States)

    Vasey, Michael W.; Kotov, Roman; Frick, Paul J.; Loney, Bryan R.

    2005-01-01

    Using taxometric procedures, the latent structure of psychopathy was investigated in two studies of children and adolescents. Prior studies have identified a taxon (i.e., a natural category) associated with antisocial behavior in adults as well as children and adolescents. However, features of this taxon suggest that it is not psychopathy but…

  8. Augmenting Latent Dirichlet Allocation and Rank Threshold Detection with Ontologies

    Science.gov (United States)

    2010-03-01

    Department of Defense, or the United States Government . AFIT/GCS/ENG/10-03 Augmenting Latent Dirichlet Allocation and Rank Threshold Detection with...dog great pyrenees dalmation dog domestic dog canis familiaris dog andiron firedog dog dog-iron frump dog pawl detent click dog chap fellow feller

  9. Some Determinants of Latent Inhibition in Human Predictive Learning

    Science.gov (United States)

    Pineno, Oskar; de la Casa, Luis Gonzalo; Lubow, R. E.; Miller, Ralph R.

    2006-01-01

    The present experiments assessed the effects of different manipulations between cue preexposure and cue-outcome pairings on latent inhibition (LI) in a predictive learning task with human participants. To facilitate LI, preexposure and acquisition with the target cues took place while participants performed a secondary task. Presentation of…

  10. Estrogen Abolishes Latent Inhibition in Ovariectomized Female Rats

    Science.gov (United States)

    Nofrey, Barbara S.; Ben-Shahar, Osnat M.; Brake, Wayne G.

    2008-01-01

    Estrogen is frequently prescribed as a method of birth control and as hormone replacement therapy for post-menopausal women with varied effects on cognition. Here the effects of estrogen on attention were examined using the latent inhibition (LI) behavioral paradigm. Ovariectomized (OVX) female rats were given either estrogen benzoate (EB, 10 or…

  11. Context-dependent latent inhibition in preweanling rats.

    Science.gov (United States)

    Revillo, D A; Gaztañaga, M; Aranda, E; Paglini, M G; Chotro, M G; Arias, C

    2014-11-01

    Preexposure to a conditioned stimulus (CS) usually weakens conditioning, an effect known as latent inhibition. Similar to other learning interference effects, latent inhibition has been characterized as context-dependent, which means that the magnitude of this effect can be attenuated by changing the context between the different phases of the procedure (e.g., preexposure and conditioning). Latent inhibition has been found with a variety of procedures in infant rats, but the few studies that examined the context-dependency of this phenomenon during this ontogenetic period found no context-change effect. The present study explored the context-dependency of latent inhibition during infancy using a conditioned taste aversion preparation and employing contexts enriched with distinctive odors to increase the possible efficacy of the context manipulation. Experiment 1 showed that three preexposures to the CS (saccharin) were sufficient to retard conditioning to the same CS, although this effect was also observed in a control group preexposed to an alternative taste stimulus (saline), in comparison with a non-preexposed control group. In Experiment 2a, the CS-preexposure effect was found to be specific to the preexposed CS when the number of preexposures was increased. This effect was revealed as context-dependent in Experiment 2b, since it was attenuated by changing the context between preexposure and conditioning. The present result is consistent with recent studies showing the context-dependency of extinction in preweanling rats, thus demonstrating these animals' capacity to learn about context early on in their development.

  12. Latent Inhibition in an Insect: The Role of Aminergic Signaling

    Science.gov (United States)

    Fernandez, Vanesa M.; Giurfa, Martin; Devaud, Jean-Marc; Farina, Walter M.

    2012-01-01

    Latent inhibition (LI) is a decrement in learning performance that results from the nonreinforced pre-exposure of the to-be-conditioned stimulus, in both vertebrates and invertebrates. In vertebrates, LI development involves dopamine and serotonin; in invertebrates there is yet no information. We studied differential olfactory conditioning of the…

  13. Rolipram attenuates MK-801-induced deficits in latent inhibition.

    Science.gov (United States)

    Davis, Jennifer A; Gould, Thomas J

    2005-04-01

    Latent inhibition is used to examine attention and study cognitive deficits associated with schizophrenia. Research using MK-801, an N-methyl-D-aspartate (NMDA) open channel blocker, implicates glutamate receptors in acquisition of latent inhibition of cued fear conditioning. Evidence suggests an important relationship between NMDA-induced increases in cyclic adenosine monophosphate (cAMP) and learning and memory. The authors examine whether amplification of the cAMP signaling pathway by rolipram, a selective Type 4 cAMP phosphodiesterase inhibitor, reverses MK-801-induced impairments in latent inhibition. One day before training, mice were injected with MK-801, rolipram, MK-801 and rolipram, or vehicle and received 20 preexposures or no preexposures to an auditory conditioned stimulus (CS). Training consisted of 2 CS-footshock unconditioned stimulus pairings. Rolipram attenuated the disruptive effect of MK-801 on latent inhibition, which suggests a role for the cAMP signaling pathway in the task and implicates phosphodiesterase inhibition as a target for treating cognitive impairments associated with schizophrenia.

  14. Bayesian latent feature modeling for modeling bipartite networks with overlapping groups

    DEFF Research Database (Denmark)

    Jørgensen, Philip H.; Mørup, Morten; Schmidt, Mikkel Nørgaard;

    2016-01-01

    Bi-partite networks are commonly modelled using latent class or latent feature models. Whereas the existing latent class models admit marginalization of parameters specifying the strength of interaction between groups, existing latent feature models do not admit analytical marginalization...... of the parameters accounting for the interaction strength within the feature representation. We propose a new binary latent feature model that admits analytical marginalization of interaction strengths such that model inference reduces to assigning nodes to latent features. We propose a constraint inspired...... to the infinite relational model and the infinite Bernoulli mixture model. We find that the model provides a new latent feature representation of structure while in link-prediction performing close to existing models. Our current extension of the notion of communities and collapsed inference to binary latent...

  15. Tolerancia al calor y humedad atmosférica de diferentes grupos raciales de ganado bovino

    Directory of Open Access Journals (Sweden)

    Ariel Guillén T

    2011-04-01

    Full Text Available Objetivo. Comparar algunas respuestas fisiológicas al calor y humedad atmosférica entre bovinos Chinampos (Bos taurus; Ch, ½ Charolais ½ Brahman (CB, Holstein (H y Jersey (J. Materiales y métodos. Se realizó un estudio en La Paz, México. Se utilizaron 12 vacas H, 10 J, 15 Ch y 8 CB. Durante el verano se midieron cada semana (a las 0600 y 1600 horas la frecuencia respiratoria (FR y temperatura rectal (TR. Se registraron las variables climáticas para calcular el índice de temperatura-humedad (ITH. Resultados. Durante todo el verano, la FR en los cuatro grupos estuvo por encima de los valores fisiológicos para el ganado bovino, siendo superior en H y J que en Ch y CB (p<0.01. En todos los grupos, la TR estuvo dentro de los límites fisiológicos de la especie estudiada. El grupo racial más afectado fue H (p<0.05. Cuando las constantes fisiológicas fueron analizadas dentro de cada una de tres categorías de ITH (<72, ≥72<78, y ≥78, las vacas H y J mostraron FR superior a las Ch y CB (p<0.01. La TR aumentó conforme se elevó el ITH siendo más marcado en J y H. El incremento de la FR entre la mañana y la tarde de cada día de medición fue mayor en H y J que en Ch y CB (p<0.05. La TR se incrementó más en H que en Ch (p<0.05. Conclusiones. Los grupos raciales más tolerantes al estrés por calor, determinado con base en FR y TR fueron Ch y CB.

  16. Heat transfer in simple houses; Transferencia de calor en casas habitacion

    Energy Technology Data Exchange (ETDEWEB)

    Porta, Miguel Angel; Rubio, Eduardo; Fernandez, Jose Luis [Centro de Investigaciones Biologicas del Noroeste, Baja California Sur, (Mexico); Gomez Munoz, Victor [Centro Interdiciplinario de Ciencias Marinas, Baja California Sur (Mexico)

    2000-07-01

    A lumped parameter model is used to represent, with a high degree of precision, the temperature and comfort evolution with the time of a simple house, under any hot, extreme weather variation. Results are validated by experimental work in physical models, built to scale 1:2, with materials and building techniques typical of social interest housing in Baja California, Mexico. With the mathematical model properly calibrated, adequately validated heat transfer coefficients between walls, ceiling and windows are calculated. Sensitivity analyses lead to values of heat loads in simple houses with varying shapes, orientation, shading devices, and construction materials and techniques. Energy balance in the present work is achieved by means of three simultaneous equations, each depicting energy equilibrium in one of the basic building elements: the window glazing, the building materials, and inside air. Simultaneous solution of the equations is accomplished with of the Kutta method, which yields the representative temperature along the day of each of the components, while heat flow among them is calculated, together with thermal exchange with the environment. Comfort levels, energy consumption and saving are hence easily derived, and the economical pertinence of passive elements can be evaluated. [Spanish] Este trabajo presenta un modelo matematico de parametros concentrados que representa, de manera apropiada, el comportamiento de una casa habitacion tipica a lo largo de un dia cualquiera. Los resultados se validan mediante la experimentacion en modelo fisico, donde se ensayan casetas de material y dimensiones similares a las casas de interes social, a escala 1:2. Una vez que se ha calibrado el modelo, se pueden determinar, mediante corridas apropiadas en computadora, los coeficientes especificos de transferencia de calor en muros, ventanas y techo. Los analisis subsecuentes de sensibilidad producen informacion util para conocer los requerimientos energeticos de cada casa

  17. Effect of caloric restriction on myenteric neuroplasticity in the rat duodenum during aging.

    Science.gov (United States)

    da Silva Porto, Gisele; Bertaglia Pereira, Joice Naiara; Tibúrcio, Vanessa Graciele; Stabille, Sandra Regina; Garcia de Faria, Haroldo; de Melo Germano, Ricardo; de Britto Mari, Renata

    2012-05-21

    The objective of this study was to evaluate the effects of caloric restriction (CR) on myenteric neurons in the duodenum of Wistar rats during aging. Thirty rats were divided into three groups: the C group (six-month-old animals that were fed a normal diet from weaning until six months of age), the SR group (18-month-old animals that were fed a normal diet from weaning until 18 months of age) and the CR group (18-month-old animals that were fed a 30% CR diet after six months of age). After 12 months, the animals were euthanized. Whole-mount preparations of the duodenums were either stained with Giemsa or underwent NADPH-diaphorase histochemistry to determine the general myenteric neuron population and the nitrergic neuron subpopulation (NADPH-d+), respectively. The NADPH-d-negative (NADPH-d-) neuron population was estimated based on the difference between the Giemsa-stained and NADPH-d+ neurons. The neurons were counted, and the cell body areas were measured. Aging was associated with neuronal loss in the SR group, which was minimized by caloric restriction in the CR group. The density (mm(2)) of the Giemsa-stained neurons was higher in the SR group (79.09 ± 6.25) than in the CR (92.37 ± 11.6) and C (111.68 ± 15.26) groups. The density of the NADPH-d+ neurons was higher in the SR group (44.90 ± 5.88) than in the C (35.75 ± 1.6) and RC (39.14 ± 7.02) groups. The density of NADPH-d- neurons was higher in the CR (49.73 ± 12.08) and C (75.64 ± 17.05) groups than in the SR group (33.82 ± 4.5). In the C group, 32% and 68% of the Giemsa-stained myenteric neurons were NADPH-d+ or NADPH-d-, respectively. With aging (SR group), the percentage of nitrergic neurons (56.77%) increased, whereas the percentage of NADPH-d- neurons (43.22%) decreased. In the CR group, the change in the percentage of nitrergic (42.37%) and NADPH-d- (57.62%) neurons was lower. As NADPH-d- neurons will be mostly cholinergic neurons, CR appears to reduce the loss of cholinergic neurons during

  18. Accumulation of long-chain glycosphingolipids during aging is prevented by caloric restriction.

    Directory of Open Access Journals (Sweden)

    María José Hernández-Corbacho

    Full Text Available BACKGROUND: Chronic kidney disease and end-stage renal disease are major causes of morbidity and mortality that are seen far more commonly in the aged population. Interestingly, kidney function declines during aging even in the absence of underlying renal disease. Declining renal function has been associated with age-related cellular damage and dysfunction with reports of increased levels of apoptosis, necrosis, and inflammation in the aged kidney. Bioactive sphingolipids have been shown to regulate these same cellular processes, and have also been suggested to play a role in aging and cellular senescence. METHODOLOGY/PRINCIPAL FINDINGS: We hypothesized that alterations in kidney sphingolipids play a role in the declining kidney function that occurs during aging. To begin to address this, the sphingolipid profile was measured in young (3 mo, middle aged (9 mo and old (17 mo C57BL/6 male mice. Interestingly, while modest changes in ceramides and sphingoid bases were evident in kidneys from older mice, the most dramatic elevations were seen in long-chain hexosylceramides (HexCer and lactosylceramides (LacCer, with C14- and C16-lactosylceramides elevated as much as 8 and 12-fold, respectively. Increases in long-chain LacCers during aging are not exclusive to the kidney, as they also occur in the liver and brain. Importantly, caloric restriction, previously shown to prevent the declining kidney function seen in aging, inhibits accumulation of long-chain HexCer/LacCers and prevents the age-associated elevation of enzymes involved in their synthesis. Additionally, long-chain LacCers are also significantly elevated in human fibroblasts isolated from elderly individuals. CONCLUSION/SIGNIFICANCE: This study demonstrates accumulation of the glycosphingolipids HexCer and LacCer in several different organs in rodents and humans during aging. In addition, data demonstrate that HexCer and LacCer metabolism is regulated by caloric restriction. Taken together

  19. Anual variation of morphologic traits and hair coat surface temperature of Holstein cows in semi-arid environment Variação anual de características morfológicas e da temperatura de superfície do pelame de vacas da raça Holandesa em ambiente semiárido

    Directory of Open Access Journals (Sweden)

    Débora Andréa Evangelista Façanha

    2010-04-01

    Full Text Available This work aimed to study the annual variation of temperature of the coat surface and other traits of coat in Holstein cows managed in a tropical environment by separately considering black coat and white coat. It was measured the coat thickness (mm characteristic, hair length (mm, hair number (hair/cm² and coat surface temperature on 191 crossbred cows with 7/8 and 31/32 Holstein composition distributed in 3 herds in a semi-arid environment. Less dense coats with shorter, flattened hair occurred predominantly in March, a time coinciding to high levels of solar radiation. This type of coat shows low resistance to the flux of latent and sensitive heat through the skin, thus favoring heat loss. The black coat surface temperature was on average 4ºC higher than that of the white one during all the year and its variation followed that of the mean radiant temperature. The models developed to predict the effective thermal conductivity of the coat must take these differences into account because the thermal gradient parallel to the skin surface is not negligible for Holstein cows under the sun in a tropical environment, as well as the other traits.O objetivo neste trabalho foi estudar a variação anual da temperatura superficial e outras características do pelame de vacas holandesas em ambiente tropical, considerando separadamente as malhas negras e brancas. Foram medidas as características espessura da capa (mm, comprimento dos pelos (mm, número de pelos (pelos/cm² e temperatura da superfície do pelame em 191 vacas mestiças com alta proporção de sangue holandês (7/8 e 31/32, respectivamente, distribuídas em três rebanhos em ambiente semiárido. O pelame menos denso, com pelos mais curtos e assentados, que ocorreu predominantemente no mês de março, coincidiu com altos níveis de radiação solar. Esse tipo de pelame apresenta menor resistência ao fluxo de calor latente e sensível através da capa, favorecendo a termólise. A temperatura

  20. Absorption heat pump integrated in an effluent purification system; Bomba de calor por absorcion integrada a un sistema de purificacion de efluentes

    Energy Technology Data Exchange (ETDEWEB)

    Santoyo, Socrates; Siqueiros, Javier; Heard, Christopher; Santoyo, Edgar [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1996-12-31

    The results derived of the integration of an absorption heat pump to an industrial effluents purification system, are presented. The advantages of these heat pumps with respect to heat pumps by mechanical compression of vapor, as well as the advantages in using absorption heat pumps in simple distillation systems, are mentioned. Finally, a description is made of the equipment designed and built, as well as the results obtained in a preliminary test. [Espanol] Se presentan los resultados derivados de la integracion de una bomba de calor por absorcion a un sistema de purificacion de efluentes industriales. Se mencionan las ventajas de este tipo de bombas de calor con respecto a las de calor por compresion mecanica de vapor, asi como las ventajas de usar bombas de calor en sistemas de destilacion simple. Finalmente, se describe el equipo disenado y construido, asi como los resultados obtenidos de una prueba preliminar.

  1. Calores de Solución y Propiedades Termodinámicas Relacionadas: Un método Gráfico General de Cálculo

    OpenAIRE

    Alfredo Gómez O.

    2009-01-01

    Se presenta un método gráfico) de cálculo) con el cual es posible evaluar a partir de datos de calor de solución. diferentes propiedades termodinámicas de interés tales como: calores)res diferenciales de solución del soluto y del solvente. A HD,P 2 V ^ HOIF.I • calor de solución a dilución infinita A tH°; entalpias molares parciales relativas del soluto y del solvente. Lj y L,. y la entalpia molar aparente relativa, L^. El método está basado en la representación gráfica del calor integral de...

  2. Skin Resistivity Value of Upper Trapezius Latent Trigger Points

    Directory of Open Access Journals (Sweden)

    Elżbieta Skorupska

    2015-01-01

    Full Text Available Introduction. The skin resistivity (SkR measurement is commonly recommended for acupoints measurement, but for trigger points (TrPs only one study is available. The purpose of the study was to evaluate SkR for latent TrPs compared to non-TrPs and the surrounding tissue. Material and Methods. Forty-two healthy volunteers with unilateral latent upper trapezius TrPs (12 men, 30 women aged 21–23 (mean age: 22.1 ± 0.6 y participated in the study. Keithley electrometer 610B was used for measuring SkR (Ag/AgCl self-adhesive, disposable ground electrode: 30 mm diameter. SkR was measured for latent TrPs and compared to opposite non-TrPs sites and the surrounding tissue. Results. The SkR decrease of TrPs-positive sites as compared to TrPs-negative sites and the surrounding tissue was confirmed. However, no statistically significant difference in the SkR value occurred when all data were analyzed. The same was confirmed after gender division and for TrPs-positive subjects examined for referred pain and twitch response presence. Conclusion. SkR reactive changes at latent TrPs are possible but the results were not consistent with the previous study. Thus, caution in applying SkR to latent TrPs isolation is recommended and its clinical use should not be encouraged yet. Further studies, especially on active TrPs, are yet required.

  3. Improved magneto-caloric effect of the Gd50Co50 metallic glass by minor Si addition

    Science.gov (United States)

    Tang, B. Z.; Yu, P.; Ding, D.; Wu, C.; Xia, L.

    2017-02-01

    In the present work, we studied the effect of minor Si addition on the magneto-caloric effect (MCE) of the Gd50Co50 metallic glass. The Gd50Co50-xSix (x=2, 5) as-spun ribbons show typical amorphous characteristics in structure and magneto-caloric behaviors. The peak values for the magnetic entropy change (-ΔSmpeak) of the Gd50Co50-xSix (x=0, 2, 5) metallic glasses increase significantly with the addition of Si. The mechanism for the enhanced MCE by minor addition of Si was investigated by revealing the relationship between -ΔSmpeak and the Curie temperature in the Gd-Co-based amorphous ribbons.

  4. Better Living through Chemistry: Caloric Restriction (CR) and CR Mimetics Alter Genome Function to Promote Increased Health and Lifespan

    Science.gov (United States)

    Gillespie, Zoe E.; Pickering, Joshua; Eskiw, Christopher H.

    2016-01-01

    Caloric restriction (CR), defined as decreased nutrient intake without causing malnutrition, has been documented to increase both health and lifespan across numerous organisms, including humans. Many drugs and other compounds naturally occurring in our diet (nutraceuticals) have been postulated to act as mimetics of caloric restriction, leading to a wave of research investigating the efficacy of these compounds in preventing age-related diseases and promoting healthier, longer lifespans. Although well studied at the biochemical level, there are still many unanswered questions about how CR and CR mimetics impact genome function and structure. Here we discuss how genome function and structure are influenced by CR and potential CR mimetics, including changes in gene expression profiles and epigenetic modifications and their potential to identify the genetic fountain of youth. PMID:27588026

  5. Fish oil supplementation is beneficial on caloric intake, appetite and mid upper arm muscle circumference in children with leukaemia.

    Science.gov (United States)

    Abu Zaid, Zalina; Shahar, Suzana; Jamal, A Rahman A; Mohd Yusof, Noor Aini

    2012-01-01

    A randomised trial was carried out to determine the effect of supplementation of fish oil among 51 children with leukaemia aged 4 to 12 years on appetite level, caloric intake, body weight and lean body mass. They were randomly allocated into the trial group (TG) and the control group (CG). At baseline, 30.8% of TG subjects and 44.0% of CG subjects were malnourished and 7.7% of subject from TG and 28.0% from CG were classified as stunted. The majority of subjects from TG and CG were in the mild malnutrition category for mid upper arm muscle circumference (MUAMC)-for-age. The TG group showed significant increment in MUAMC (0.13 cm vs -0.09 cm) compared with CG at 8 weeks (pappetite level (0.12±0.33) (pappetite level, caloric intake and MUAMC among children with leukaemia.

  6. Protótipo de um sistema de aquecimento de água para população de baixa renda usando energia solar e elétrica, com reaproveitamento de calor

    Directory of Open Access Journals (Sweden)

    Marco Antônio Silva Pereira

    2016-01-01

    Full Text Available Este artigo consiste em uma pesquisa sobre os vários meios de aquecimento de água para o banho, buscando o uso de alternativas para viabilizar o acesso da população de baixa renda a esses benefícios. A ideia principal é fazer uma combinação dos vários sistemas existentes a fim de produzir um protótipo eficiente e de baixo custo. O protótipo constitui-se de um sistema de aquecimento solar, recuperador de calor e de um misturador de água automatizado. A representação do sistema foi obtida por meio de uma maquete do protótipo ecológico de chuveiro, englobando as diversas tecnologias estudadas.Palavras-chave: Aquecedor solar. Recuperador de calor. Misturador automatizado. Microcontrolador.Prototype of a water heating system for low-income population using solar energy and power, with reuse of heatAbstractThis paper consists of a survey on the various means of heating water for the bath, trying to use of alternatives to allow access of the low-income population. The main idea is to make a blend of various existing systems in order to produce an efficient and cost effective prototype. The prototype consists of a system of solar heating, heat recovery and an automated water mixer. The representation of the system was obtained through a model of the ecological prototype shower encompassing the several studied technologies.Keywords: Solar heating. Heat recovery. Automated mixer. Microcontroller.

  7. The effect of brand and caloric information on flavor perception and food consumption in restrained and unrestrained eaters.

    Science.gov (United States)

    Cavanagh, Kevin V; Kruja, Blina; Forestell, Catherine A

    2014-11-01

    The goal of the current study was to determine whether provision of brand and caloric information affects sensory perception and consumption of a food in restrained (n=84) and unrestrained eaters (n=104). Using a between-subjects 2 × 2 × 3 design, female restrained and unrestrained eaters were asked to taste and rate a cookie that was labeled with a brand associated with healthful eating (Kashi(®)) or one associated with unhealthful eating (Nabisco(®)). Additionally, some participants were presented with a nutrition label alongside the brand name indicating that one serving contained 130 calories (Low-Calorie Condition), or 260 calories (High-Calorie Condition). The remaining participants were not shown a nutrition label (No Label Condition). Results indicated that those in the No Label or the High-Calorie Condition perceived the healthful branded cookie to have a better flavor than those who received the unhealthful branded cookie regardless of their restraint status. However, restrained eaters in the No Label Condition consumed more of the healthful than the unhealthful branded cookie, whereas those in the Low-Calorie Condition consumed more of the unhealthful than the healthful branded cookie. In contrast, unrestrained eaters ate more of the healthful branded cookie regardless of the caloric information provided. Thus, although restrained and unrestrained eaters' perceptions are similarly affected by branding and caloric information, brands and caloric information interact to affect restrained eaters' consumption. This study reveals that labeling foods as low calorie may create a halo effect which may lead to over-consumption of these foods in restrained eaters.

  8. Effects of age and caloric restriction in the vascular response of renal arteries to endothelin-1 in rats.

    Science.gov (United States)

    Amor, Sara; García-Villalón, Angel Luis; Rubio, Carmen; Carrascosa, Jose Ma; Monge, Luis; Fernández, Nuria; Martín-Carro, Beatriz; Granado, Miriam

    2017-02-01

    Cardiovascular alterations are the most prevalent cause of impaired physiological function in aged individuals with kidney being one the most affected organs. Aging-induced alterations in renal circulation are associated with a decrease in endothelium-derived relaxing factors such as nitric oxide (NO) and with an increase in contracting factors such as endothelin-1(ET-1). As caloric restriction (CR) exerts beneficial effects preventing some of the aging-induced alterations in cardiovascular system, the aim of this study was to analyze the effects of age and caloric restriction in the vascular response of renal arteries to ET-1 in aged rats. Vascular function was studied in renal arteries from 3-month-old Wistar rats fed ad libitum (3m) and in renal arteries from 8-and 24-month-old Wistar rats fed ad libitum (8m and 24m), or subjected to 20% caloric restriction during their three last months of life (8m-CR and 24m-CR). The contractile response to ET-1 was increased in renal arteries from 8m and 24m compared to 3m rats. ET-1-induced contraction was mediated by ET-A receptors in all experimental groups and also by ET-B receptors in 24m rats. Caloric restriction attenuated the increased contraction to ET-1 in renal arteries from 8m but not from 24m rats possibly through NO release proceeding from ET-B endothelial receptors. In 24m rats, CR did not attenuate the aging-increased response of renal arteries to ET-1, but it prevented the aging-induced increase in iNOS mRNA levels and the aging-induced decrease in eNOS mRNA levels in arterial tissue. In conclusion, aging is associated with an increased response to ET-1 in renal arteries that is prevented by CR in 8m but not in 24m rats.

  9. Effect of replacing sugar with non-caloric sweeteners in beverages on the reward value after repeated exposure.

    Directory of Open Access Journals (Sweden)

    Sanne Griffioen-Roose

    Full Text Available BACKGROUND: The reward value of food is partly dependent on learned associations. It is not yet known whether replacing sugar with non-caloric sweeteners in food is affecting long-term acceptance. OBJECTIVE: To determine the effect of replacing sugar with non-caloric sweeteners in a nutrient-empty drink (soft drink versus nutrient-rich drink (yoghurt drink on reward value after repeated exposure. DESIGN: We used a randomized crossover design whereby forty subjects (15 men, 25 women with a mean ± SD age of 21 ± 2 y and BMI of 21.5 ± 1.7 kg/m(2 consumed a fixed portion of a non-caloric sweetened (NS and sugar sweetened (SS versions of either a soft drink or a yoghurt drink (counterbalanced for breakfast which were distinguishable by means of colored labels. Each version of a drink was offered 10 times in semi-random order. Before and after conditioning the reward value of the drinks was assessed using behavioral tasks on wanting, liking, and expected satiety. In a subgroup (n=18 fMRI was performed to assess brain reward responses to the drinks. RESULTS: Outcomes of both the behavioral tasks and fMRI showed that conditioning did not affect the reward value of the NS and SS versions of the drinks significantly. Overall, subjects preferred the yoghurt drinks to the soft drinks and the ss drinks to the NS drinks. In addition, they expected the yoghurt drinks to be more satiating, they reduced hunger more, and delayed the first eating episode more. Conditioning did not influence these effects. CONCLUSION: Our study showed that repeated consumption of a non-caloric sweetened beverage, instead of a sugar sweetened version, appears not to result in changes in the reward value. It cannot be ruled out that learned associations between sensory attributes and food satiating capacity which developed preceding the conditioning period, during lifetime, affected the reward value of the drinks.

  10. Effects of fructose-containing caloric sweeteners on resting energy expenditure and energy efficiency: a review of human trials

    OpenAIRE

    Tappy, L; L. Egli; Lecoultre, V.; Schneider, P.

    2013-01-01

    Epidemiological studies indicate that the consumption of fructose-containing caloric sweeteners (FCCS: mainly sucrose and high-fructose corn syrup) is associated with obesity. The hypothesis that FCCS plays a causal role in the development of obesity however implies that they would impair energy balance to a larger extent than other nutrients, either by increasing food intake, or by decreasing energy expenditure. We therefore reviewed the literature comparing a) diet-induced thermogenesis (DI...

  11. Exploring the Estimation of Examinee Locations Using Multidimensional Latent Trait Models under Different Distributional Assumptions

    Science.gov (United States)

    Jang, Hyesuk

    2014-01-01

    This study aims to evaluate a multidimensional latent trait model to determine how well the model works in various empirical contexts. Contrary to the assumption of these latent trait models that the traits are normally distributed, situations in which the latent trait is not shaped with a normal distribution may occur (Sass et al, 2008; Woods…

  12. Marginal Maximum Likelihood Estimation of a Latent Variable Model with Interaction

    Science.gov (United States)

    Cudeck, Robert; Harring, Jeffrey R.; du Toit, Stephen H. C.

    2009-01-01

    There has been considerable interest in nonlinear latent variable models specifying interaction between latent variables. Although it seems to be only slightly more complex than linear regression without the interaction, the model that includes a product of latent variables cannot be estimated by maximum likelihood assuming normality.…

  13. Defining a Family of Cognitive Diagnosis Models Using Log-Linear Models with Latent Variables

    Science.gov (United States)

    Henson, Robert A.; Templin, Jonathan L.; Willse, John T.

    2009-01-01

    This paper uses log-linear models with latent variables (Hagenaars, in "Loglinear Models with Latent Variables," 1993) to define a family of cognitive diagnosis models. In doing so, the relationship between many common models is explicitly defined and discussed. In addition, because the log-linear model with latent variables is a general model for…

  14. Polytomous latent scales for the investigation of the ordering of items

    NARCIS (Netherlands)

    Ligtvoet, R.; van der Ark, L.A.; Bergsma, W. P.; Sijtsma, K.

    2011-01-01

    We propose three latent scales within the framework of nonparametric item response theory for polytomously scored items. Latent scales are models that imply an invariant item ordering, meaning that the order of the items is the same for each measurement value on the latent scale. This ordering prope

  15. Respostas pós-colheita de abacaxi 'Pérola' no tratamento com calor e armazenagem refrigerada Postharvest behavior of 'Perola' pineapples to heat treatments cold storage

    Directory of Open Access Journals (Sweden)

    Rosilene Ferreira Souto

    2010-01-01

    Full Text Available Este trabalho teve como objetivo avaliar o efeito de diferentes temperaturas de armazenamento e do tratamento inicial a 40 ºC, por 24 horas, na preservação de abacaxis 'Pérola'. Os abacaxis foram colhidos no estádio de maturação "pintado", tratados com calor e foram mantidos sob condição de ambiente (25 ºC e 75-80% UR ou refrigerados durante 17 dias, a 8 ºC, ou 14 ºC. Após este período, foram transferidos para condição de ambiente, 25 ºC e 75-80% UR. As avaliações foram realizadas no início (0 dia e após 1; 5; 9; 13 ou 17 dias. Os frutos armazenados sob refrigeração foram transferidos para o ambiente e também foram avaliados aos 21, 25 ou 29 dias. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema fatorial (2x3x9, tendo-se os fatores, frutos tratados com calor ou não, três temperaturas de armazenamento e 9 épocas de avaliação. Os frutos foram avaliados quanto à perda de massa fresca, coloração externa, resistência da casca e da polpa, rendimento em polpa, além da intensidade respiratória. A perda de massa fresca e a resistência da casca e da polpa foram maiores nos frutos armazenados sob condição ambiente quando comparada à perda de massa e resistência dos abacaxis armazenados sob refrigeração, com variação na coloração da casca, de verde para amarela, com a evolução do tempo. Os abacaxis mantidos sob refrigeração a 8 ºC ou 14 ºC tiveram vida útil de 29 dias, enquanto os abacaxis mantidos a 25 ºC foram descartados após 17 dias. Abacaxis tratados com calor apresentaram a maior taxa respiratória, enquanto aqueles mantidos a 8 ºC apresentaram a menor atividade respiratória, tanto sob refrigeração como em condição ambiente.This work aimed to evaluate the effect of different temperature storage and a initial treatment at 40 ºC for 24 hours, to preserve 'Perola' pineapples. Pineapples were harvested at "pintado" ripening stage, heated and stored under

  16. Islas de calor urbano en Tampico, México. Impacto del microclima a la calidad del hábitat

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Fuentes Pérez

    2014-01-01

    Full Text Available De todas las modificaciones climáticas por causa urbana, las térmicas son las más conocidas por los propios ciudadanos. La acción transformadora del espacio natural sobre el que se realiza el emplazamiento de la ciudad, llega a ser productora en gran medida de sus condiciones ambientales, incluida la climatología urbana. Todo proceso de urbanización sustituye los suelos y áreas naturales por superficies construidas, cuyos materiales se caracterizan por una baja reflectividad, con disminución de la capacidad de absorción de agua y un comportamiento térmico propicio para el almacenamiento y la emisión de calor. Estos elementos coadyuvan a realzar la temperatura atmosférica de la ciudad en relación con su entorno menos urbanizado a través de un fenómeno conocido como efecto de islas de calor urbano, produciendo un impacto del microclima a la calidad del hábitat. La presente investigación experimental aplicada tiene como objetivo, demostrar la metodología de investigación adoptada, para realizar las islas de calor urbanas en Tampico, México.

  17. General and persistent effects of high-intensity sweeteners on body weight gain and caloric compensation in rats.

    Science.gov (United States)

    Swithers, Susan E; Baker, Chelsea R; Davidson, T L

    2009-08-01

    In an earlier work (S. E. Swithers & T. L. Davidson, 2008), rats provided with a fixed amount of a yogurt diet mixed with saccharin gained more weight and showed impaired caloric compensation relative to rats given the same amount of yogurt mixed with glucose. The present 4 experiments examined the generality of these findings and demonstrated that increased body weight gain was also demonstrated when animals consumed a yogurt diet sweetened with an alternative high-intensity sweetener (acesulfame potassium; AceK) as well as in animals given a saccharin-sweetened base diet (refried beans) that was calorically similar but nutritionally distinct from low-fat yogurt. These studies also extended earlier findings by showing that body weight differences persist after saccharin-sweetened diets are discontinued and following a shift to a diet sweetened with glucose. In addition, rats first exposed to a diet sweetened with glucose still gain additional weight when subsequently exposed to a saccharin-sweetened diet. The results of these experiments add support to the hypothesis that exposure to weak or nonpredictive relationships between sweet tastes and caloric consequences may lead to positive energy balance.

  18. PROCEDIMIENTO DE CALIBRACIÓN EN TEMPERATURA Y FLUJO DE CALOR DE UN CALORÍMETRO DIFERENCIAL DE BARRIDO (DSC

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    Pablo E. Reynoso

    2016-01-01

    Full Text Available El calorímetro diferencial de barrido no es un dispositivo de medición absoluta, por lo que su utilización requiere indispensable mente una calibración. En esta contribución se presenta un procedimiento de calibración para el cual s e consideraron las temperaturas y calores de fusión aceptados en la literatura de 5 materiales puros . S e prepararon 6 muestras de dife rentes masas para cada material y s e sometió cada una de ellas a ci clos de calentamiento , desde temperatura ambiente hasta 50 ºC por encima de las temperaturas de fusión , utilizando 6 velocidades distintas por cada probeta. Luego, p ara determinar una relación de ajuste entre los datos experimentales obtenidos y los valores aceptados , se utilizó un método de regresión no lineal mediante un procedimiento matricial desarrollado en el entorno MATLAB . Los resultados obtenidos muestran una corrección con una desviación estándar de 1,2 ºC para el ajuste en temperatura y 2,1 5 J/g para el flujo de calor.

  19. Caloric Intake on the Sabbath: A Pilot Study of Contributing Factors to Obesity in the Orthodox Jewish Community.

    Science.gov (United States)

    Rosenberg, Deborah A; Swencionis, Charles; Segal-Isaacson, C J

    2016-10-01

    The American Orthodox Jewish community has specific cultural factors that may contribute to overweight and obesity. This study aimed to look at caloric intake on the Sabbath and its contribution to overweight and obesity. Twelve married or previously married women who identify themselves as Orthodox Jews were recruited to do 24-h food recalls over the phone. The participants were divided into three weight groups (normal, overweight, and obese) based on their BMI. The overweight and obese participants' data were combined into one group for the purposes of statistical testing. Paired t tests looking at the data for all participants showed significantly great caloric intake during an average Sabbath day than an average weekday [t(4) = 7.58, p Sabbath for the overweight-obese women compared to the normal weight women [F(1) = 7.83, p = 0.02]. No statistical difference was seen between the weekday energy intake of the normal weight women as compared to the combined group of overweight-obese women [F(1) = 0.501, p = 0.499]. These results support the hypotheses that all groups eat significantly more on the Sabbath than on weekdays, and overweight and obese individuals eat significantly more on the Sabbath than normal weight individuals. This supports the theory that caloric intake on the Sabbath is a contributing factor to overweight and obesity within the American Orthodox Jewish community.

  20. Nonnutritive, Low Caloric Substitutes for Food Sugars: Clinical Implications for Addressing the Incidence of Dental Caries and Overweight/Obesity

    Directory of Open Access Journals (Sweden)

    Michael W. Roberts

    2012-01-01

    Full Text Available Caries and obesity are two common conditions affecting children in the United States and other developed countries. Caries in the teeth of susceptible children have often been associated with frequent ingestion of fermentable sugars such as sucrose, fructose, glucose, and maltose. Increased calorie intake associated with sugars and carbohydrates, especially when associated with physical inactivity, has been implicated in childhood obesity. Fortunately, nonnutritive artificial alternatives and non-/low-caloric natural sugars have been developed as alternatives to fermentable sugars and have shown promise in partially addressing these health issues. Diet counseling is an important adjunct to oral health instruction. Although there are only five artificial sweeteners that have been approved as food additives by the Food and Drug Administration (FDA, there are additional five non-/low caloric sweeteners that have FDA GRAS (Generally Recognized as Safe designation. Given the health impact of sugars and other carbohydrates, dental professionals should be aware of the nonnutritive non-/low caloric sweeteners available on the market and both their benefits and potential risks. Dental health professionals should also be proactive in helping identify patients at risk for obesity and provide counseling and referral when appropriate.

  1. Studies of Phase Change Materials and a Latent Heat Storage Unit Used for a Natural Circulation Cooling/Latent Heat Storage System

    Science.gov (United States)

    Sakitani, Katsumi; Honda, Hiroshi

    Experimental and theoretical studies were made of the heat transfer characteristics of a latent heat storage unit used for a natural circulation cooling /latent heat storage system. Heating and cooling curves of the latent heat storage unit undergoing solid-liquid phase change of a PCM (lauric acid) was obtained by using anatural circulation loop of R22 which consisted of an electrically heated evaporater, a water cooled condenser and the latent heat storage unit. The latent heat storage unit showed a heat transfer performance which was high enough for practical use. An approximate theoretical analysis was conducted to investigate transient behavior of the latent heat storage unit. Predictions of the refrigerant and outer surface temperatures during the melting process were in fair agreement with the experimental data, whereas that of the refrigerant temperature during the solidification process was considerably lower than the measurement.

  2. Evaluation of dysphagia risk, nutritional status and caloric intake in elderly patients with Alzheimer's

    Directory of Open Access Journals (Sweden)

    Vanessa Fernanda Goes

    2014-04-01

    Full Text Available OBJECTIVE: to evaluate the risk of dysphagia and its relationship with the stage of Alzheimer's Disease, as well as the relationship between the risk of dysphagia and nutritional status and caloric intake in elderly people with Alzheimer's disease.METHODS: the sample consisted of 30 subjects of both genders with probable Alzheimer's disease. The stage of the disease, nutritional status, energy intake, and risk of dysphagia were assessed.RESULTS: it was found that increased risk of dysphagia is associated with the advance in the stages of Alzheimer's disease and that even patients in the early stages of disease have a slight risk of developing dysphagia. No association was found between nutritional status and the risk of dysphagia. High levels of inadequate intake of micronutrients were also verified in the patients.CONCLUSION: an association between dysphagia and the development of Alzheimer's disease was found. The results indicate the need to monitor the presence of dysphagia and the micronutrient intake in patients with Alzheimer's disease.

  3. Non-Invasive Neuromodulation Using Time-Varying Caloric Vestibular Stimulation

    Science.gov (United States)

    Rogers, Lesco L.; Ade, Kristen K.; Nicoletto, Heather A.; Adkins, Heather D.; Laskowitz, Daniel T.

    2016-01-01

    Caloric vestibular stimulation (CVS) to elicit the vestibulo-ocular reflex has long been used in clinical settings to aid in the diagnosis of balance disorders and to confirm the absence of brainstem function. While a number of studies have hinted at the potential therapeutic applications of CVS, the limitations of existing devices have frustrated that potential. Current CVS irrigators use water or air during short-duration applications; however, this approach is not tenable for longer duration therapeutic protocols or home use. Here, we describe a solid-state CVS device we developed in order to address these limitations. This device delivers tightly controlled time-varying thermal waveforms, which can be programmed through an external control unit. It contains several safety features, which limit patients to the prescribed waveform and prevent the potential for temperature extremes. In this paper, we provide evidence that CVS treatment with time-varying, but not constant temperature waveforms, elicits changes in cerebral blood flow physiology consistent with the neuromodulation of brainstem centers, and we present results from a small pilot study, which demonstrate that the CVS can safely and feasibly be used longitudinally in the home setting to treat episodic migraine. Together, these results indicate that this solid-state CVS device may be a viable tool for non-invasive neuromodulation. PMID:27777829

  4. [Caloric restriction in primates: how efficient as an anti-aging approach?].

    Science.gov (United States)

    Marchal, Julia; Perret, Martine; Aujard, Fabienne

    2012-12-01

    Caloric restriction (CR) is the only non-genetic intervention known to date to slow the onset of age-related diseases and increase average and maximum lifespan in several species. Its interest is continually growing, particularly for the identification of mechanisms involved in increasing longevity. Unlike studies in invertebrate and rodent models have provided some indication about the mechanisms of the CR, the efficacy of CR as an anti-aging protocol in primates has not yet been fully established. In this review we present the advantages of using non human primates as relevant models to the study of human aging in general and specifically in the context of therapeutic interventions applicable to humans, such as CR. Through the longitudinal findings in the Grey Mouse Lemur (Microcebus murinus), we stress the importance of primate studies in the context of research on aging and their potential to advance the development of molecules which can mimic the beneficial effects of CR, already observed in some species, without imposing a reduced calorie diet.

  5. Caloric restriction reveals a metabolomic and lipidomic signature in liver of male mice.

    Science.gov (United States)

    Jové, Mariona; Naudí, Alba; Ramírez-Núñez, Omar; Portero-Otín, Manuel; Selman, Colin; Withers, Dominic J; Pamplona, Reinald

    2014-10-01

    Lipid composition, particularly membrane unsaturation, has been proposed as being a lifespan determinant, but it is currently unknown whether caloric restriction (CR), an accepted life-extending intervention, affects cellular lipid profiles. In this study, we employ a liquid chromatography quadrupole time-of-flight-based methodology to demonstrate that CR in the liver of male C57BL/6 mice: (i) induces marked changes in the cellular lipidome, (ii) specifically reduces levels of a phospholipid peroxidation product, 1-palmitoyl-2-glutaryl-sn-glycero-3-phosphatidylcholine, (iii) alters cellular phosphoethanolamine and triglyceride distributional profiles, (iv) affects mitochondrial electron transport chain complexes, increasing complex II and decreasing complex III and (v) is associated with specific changes in liver metabolic pathways. These data demonstrate that CR induces a specific lipidome and metabolome reprogramming event in mouse liver which is associated with lower protein oxidative damage, as assessed by mass spectrometry-based measurements. Such changes may be critical to the increased lifespan and healthspan observed in C57BL/6 mice following CR.

  6. Whole-transcriptome analysis of mouse adipose tissue in response to short-term caloric restriction.

    Science.gov (United States)

    Kim, Seung-Soo; Choi, Kyung-Mi; Kim, Soyoung; Park, Taesun; Cho, In-Cheol; Lee, Jae-Won; Lee, Cheol-Koo

    2016-04-01

    Caloric restriction (CR) has been shown to extend the lifespan of many species by improving cellular function and organismal health. Additionally, fat reduction by CR may play an important role in lengthening lifespan and preventing severe age-related diseases. Interestingly, CR induced the greatest transcriptome change in the epididymal fat of mice in our study. In this transcriptome analysis, we identified and categorized 446 genes that correlated with CR level. We observed down-regulation of several signaling pathways, including insulin/insulin-like growth factor 1 (insulin/IGF-1), epidermal growth factor (EGF), transforming growth factor beta (TGF-β), and canonical wingless-type mouse mammary tumor virus integration site (Wnt). Many genes related to structural features, including extracellular matrix structure, cell adhesion, and the cytoskeleton, were down-regulated, with a strong correlation to the degree of CR. Furthermore, genes related to the cell cycle and adipogenesis were down-regulated. These biological processes are well-identified targets of insulin/IGF-1, EGF, TGF-β, and Wnt signaling. In contrast, genes involved in specific metabolic processes, including the tricarboxylic acid cycle and the electron transport chain were up-regulated. We performed in silico analysis of the promoter sequences of CR-responsive genes and identified two associated transcription factors, Paired-like homeodomain 2 (Pitx2) and Paired box gene 6 (Pax6). Our results suggest that strict regulation of signaling pathways is critical for creating the optimal energy homeostasis to extend lifespan.

  7. Caloric restriction increases ketone bodies metabolism and preserves blood flow in aging brain.

    Science.gov (United States)

    Lin, Ai-Ling; Zhang, Wei; Gao, Xiaoli; Watts, Lora

    2015-07-01

    Caloric restriction (CR) has been shown to increase the life span and health span of a broad range of species. However, CR effects on in vivo brain functions are far from explored. In this study, we used multimetric neuroimaging methods to characterize the CR-induced changes of brain metabolic and vascular functions in aging rats. We found that old rats (24 months of age) with CR diet had reduced glucose uptake and lactate concentration, but increased ketone bodies level, compared with the age-matched and young (5 months of age) controls. The shifted metabolism was associated with preserved vascular function: old CR rats also had maintained cerebral blood flow relative to the age-matched controls. When investigating the metabolites in mitochondrial tricarboxylic acid cycle, we found that citrate and α-ketoglutarate were preserved in the old CR rats. We suggest that CR is neuroprotective; ketone bodies, cerebral blood flow, and α-ketoglutarate may play important roles in preserving brain physiology in aging.

  8. Krebs cycle enzymes from livers of old mice are differentially regulated by caloric restriction.

    Science.gov (United States)

    Hagopian, Kevork; Ramsey, Jon J; Weindruch, Richard

    2004-08-01

    Krebs cycle enzyme activities and levels of five metabolites were determined from livers of old mice (30 months) maintained either on control or on long-term caloric restriction (CR) diets (28 months). In CR mice, the cycle was divided into two major blocks, the first containing citrate synthase, aconitase and NAD-dependent isocitrate dehydrogenase which showed decreased activities, while the second block, containing the remaining enzymes, displayed increased activity (except for fumarase, which was unchanged). CR also resulted in decreased levels of citrate, glutamate and alpha-ketoglutarate, increased levels of malate, and unchanged levels of aspartate. The alpha-ketoglutarate/glutamate and malate/alpha-ketoglutarate ratios were higher in CR, in parallel with previously reported increases with CR in pyruvate carboxylase activity and glucagon levels, respectively. The results indicate that long-term CR induces a differential regulation of Krebs cycle in old mice and this regulation may be the result of changes in gene expression levels, as well as a complex interplay between enzymes, hormones and other effectors. Truncation of Krebs cycle by CR may be an important adaptation to utilize available substrates for the gluconeogenesis necessary to sustain glycolytic tissues, such as brain.

  9. Maintenance of cellular ATP level by caloric restriction correlates chronological survival of budding yeast

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Joon-Seok; Lee, Cheol-Koo, E-mail: cklee2005@korea.ac.kr

    2013-09-13

    Highlights: •CR decreases total ROS and mitochondrial superoxide during the chronological aging. •CR does not affect the levels of oxidative damage on protein and DNA. •CR contributes extension of chronological lifespan by maintenance of ATP level -- Abstract: The free radical theory of aging emphasizes cumulative oxidative damage in the genome and intracellular proteins due to reactive oxygen species (ROS), which is a major cause for aging. Caloric restriction (CR) has been known as a representative treatment that prevents aging; however, its mechanism of action remains elusive. Here, we show that CR extends the chronological lifespan (CLS) of budding yeast by maintaining cellular energy levels. CR reduced the generation of total ROS and mitochondrial superoxide; however, CR did not reduce the oxidative damage in proteins and DNA. Subsequently, calorie-restricted yeast had higher mitochondrial membrane potential (MMP), and it sustained consistent ATP levels during the process of chronological aging. Our results suggest that CR extends the survival of the chronologically aged cells by improving the efficiency of energy metabolism for the maintenance of the ATP level rather than reducing the global oxidative damage of proteins and DNA.

  10. Calor: Una Propuesta Didáctica Constructivista con Enfoque de Ciencia Integrada

    Directory of Open Access Journals (Sweden)

    Castillo Alberto de L.

    2002-01-01

    Full Text Available Realizamos un estudio comparativo entre dos diseños didácticos constructivistas para la enseñanza del tema Calor en estudiantes de carreras en ciencias naturales. Uno con un enfoque de ciencia integrada y el otro con un enfoque no integrador. En el primer diseño el alumno construye su propio conocimiento resolviendo situaciones problemáticas relacionadas a la biología y el medio-ambiente, que le permite analizar y relacionar los conceptos involucrados, mientras que en el segundo construye su conocimiento a través de la resolución de situaciones problemáicas físicas pero no biológicas. Concluimos que el primer diseño favorece en los alumnos la construcción de una estructura cognitiva del tipo integrada, que les facilita internalizar y transferir los conceptos físicos a problemas concretos de su especialidad.

  11. Higher Caloric Refeeding Is Safe in Hospitalised Adolescent Patients with Restrictive Eating Disorders

    Science.gov (United States)

    Parker, Elizabeth K.; Faruquie, Sahrish S.; Anderson, Gail; Gomes, Linette; Kennedy, Andrew; Wearne, Christine M.; Kohn, Michael R.; Clarke, Simon D.

    2016-01-01

    Introduction. This study examines weight gain and assesses complications associated with refeeding hospitalised adolescents with restrictive eating disorders (EDs) prescribed initial calories above current recommendations. Methods. Patients admitted to an adolescent ED structured “rapid refeeding” program for >48 hours and receiving ≥2400 kcal/day were included in a 3-year retrospective chart review. Results. The mean (SD) age of the 162 adolescents was 16.7 years (0.9), admission % median BMI was 80.1% (10.2), and discharge % median BMI was 93.1% (7.0). The mean (SD) starting caloric intake was 2611.7 kcal/day (261.5) equating to 58.4 kcal/kg (10.2). Most patients (92.6%) were treated with nasogastric tube feeding. The mean (SD) length of stay was 3.6 weeks (1.9), and average weekly weight gain was 2.1 kg (0.8). No patients developed cardiac signs of RFS or delirium; complications included 4% peripheral oedema, 1% hypophosphatemia (refeeding syndrome. PMID:27293884

  12. Efficient gasification of wet biomass residue to produce middle caloric gas

    Institute of Scientific and Technical Information of China (English)

    Guangwen Xu; Takahiro Murakami; Toshiyuki Suda; Hidehisa Tani; Yutaka Mito

    2008-01-01

    Various process residues represent a kind of biomass resource already concentrated but containing water as much as 60 wt.%.These materials are generally treated as waste or simply combusted directly to generate heat.Recently,we attempted to convert them into middle caloric gas to substitute for natural gas,as a chemical or a high-rank gaseous fuel for advanced combustion utilities.Such conversion is implemented through dual fluidized bed gasification (DFBG).Concerning the high water content of the fuels,DFBG was suggested to accomplish either with high-efficiency fuel drying in advance or direct decoupling of fuel drying/pyrolysis from char gasification and tar/hydrocarbon reforming.Along with fuel drying,calcium-based catalyst can be impregnated into the fuel,without much additional cost,to increase the fuel's gasification reactivity and to reduce tar formation.This article reports the Ca impregnation method and its resulting effects on gasification reactivity and tar suppression ability.Meanwhile,the principle of directly gasifying wet fuel with decoupled dual fluidized bed gasification (D-DFBG) is also highlighted.

  13. Measuring aging rates of mice subjected to caloric restriction and genetic disruption of growth hormone signaling

    Science.gov (United States)

    Koopman, Jacob J.E.; van Heemst, Diana; van Bodegom, David; Bonkowski, Michael S.; Sun, Liou Y.; Bartke, Andrzej

    2016-01-01

    Caloric restriction and genetic disruption of growth hormone signaling have been shown to counteract aging in mice. The effects of these interventions on aging are examined through age-dependent survival or through the increase in age-dependent mortality rates on a logarithmic scale fitted to the Gompertz model. However, these methods have limitations that impede a fully comprehensive disclosure of these effects. Here we examine the effects of these interventions on murine aging through the increase in age-dependent mortality rates on a linear scale without fitting them to a model like the Gompertz model. Whereas these interventions negligibly and non-consistently affected the aging rates when examined through the age-dependent mortality rates on a logarithmic scale, they caused the aging rates to increase at higher ages and to higher levels when examined through the age-dependent mortality rates on a linear scale. These results add to the debate whether these interventions postpone or slow aging and to the understanding of the mechanisms by which they affect aging. Since different methods yield different results, it is worthwhile to compare their results in future research to obtain further insights into the effects of dietary, genetic, and other interventions on the aging of mice and other species. PMID:26959761

  14. Transferencia de calor en la colada continua de aceros. II parte. Enfriamiento secundario

    Directory of Open Access Journals (Sweden)

    Cicutti, C.

    1997-12-01

    Full Text Available Once the strand leaves the mold, the solidification of steel progresses due to the heat extracted in the secondary cooling zone of the continuous casting machine. In this zone, heat is extracted mainly by: the incidence of water from sprays, radiation to surroundings contact with rolls and run out water accumulated between rolls and strand. In this work, all these mechanisms are evaluated and, when it is possible, they are quantified. Methods which are usually employed to measure solidification profiles in the continuous casting machine are also reviewed. Finally, the incidence of secondary cooling on the quality of cast products is discussed.

    La solidificación del acero iniciada en el molde continúa en la zona de enfriamiento secundario de la máquina donde el calor es extraído, principalmente por la incidencia del agua de los rociadores, la radiación al medio ambiente, el contacto con los rodillos y el agua acumulada en ellos. En este trabajo se revisa cada uno de estos mecanismos determinando, en los casos en que es posible, valores cuantitativos de los mismos. Además, se analizan los distintos métodos empleados para medir el avance del espesor solidificado en la máquina de colada continua. Por último, se discute la incidencia del enfriamiento secundario en la calidad final de los productos colados.

  15. Caloric restriction and intermittent fasting: two potential diets for successful brain aging.

    Science.gov (United States)

    Martin, Bronwen; Mattson, Mark P; Maudsley, Stuart

    2006-08-01

    The vulnerability of the nervous system to advancing age is all too often manifest in neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. In this review article we describe evidence suggesting that two dietary interventions, caloric restriction (CR) and intermittent fasting (IF), can prolong the health-span of the nervous system by impinging upon fundamental metabolic and cellular signaling pathways that regulate life-span. CR and IF affect energy and oxygen radical metabolism, and cellular stress response systems, in ways that protect neurons against genetic and environmental factors to which they would otherwise succumb during aging. There are multiple interactive pathways and molecular mechanisms by which CR and IF benefit neurons including those involving insulin-like signaling, FoxO transcription factors, sirtuins and peroxisome proliferator-activated receptors. These pathways stimulate the production of protein chaperones, neurotrophic factors and antioxidant enzymes, all of which help cells cope with stress and resist disease. A better understanding of the impact of CR and IF on the aging nervous system will likely lead to novel approaches for preventing and treating neurodegenerative disorders.

  16. Historical evolution of slope instability in the Calore River Basin, Southern Italy

    Science.gov (United States)

    Diodato, Nazzareno; Soriano, Marcella; Bellocchi, Gianni; Fiorillo, Francesco; Cevasco, Andrea; Revellino, Paola; Guadagno, Francesco Maria

    2017-04-01

    There is interest in knowing historical spatio-temporal patterns of landslide activity. However, this is challenging to reconstruct because it is difficult to obtain detailed records for past landslide activity. Here, we deal with hydro-geomorphological signatures, such as storms, downpours, floods, snowmelt and mass movement, to detect annual slope instability events (ASIEs) over historical times. In order to obtain ASIEs for each year, a monthly Instability Density Index (IDI) was used and then monthly values were summed up to obtain a yearly value. Classes of monthly IDI varying between 0 (no instability) and 4 (highest instability) were determined from historical documents. We present an application for the Calore River Basin, Southern Italy, using data from a 313-year long series (1701-2013 CE). After 1880 CE the information becomes more valuable with directly observed landslide frequency. By this cataloguing, 129 ASIEs were obtained. Their evolution shows slight instability during the 18th century. Uneven and greater slope instability occurred instead across the 19th century, when an important phase of deforestation coincided with intensification of agricultural activities. Slope instability events continued during the 20th century but their causes are mainly related to anthropisation and the effects of recent climate change. It was determined that stormy autumns until the 19th century and successive winter-times with enhanced snowmelt, may have driven the reactivation of widespread instability events. We also found that mountainous and hilly terrains have an acute sensitivity to climate change.

  17. Practical system for the direct measurement of magneto-caloric effect by micro-thermocouples.

    Science.gov (United States)

    Kamarád, J; Kaštil, J; Arnold, Z

    2012-08-01

    A system for direct measurements of the magneto-caloric effect (MCE) exploits a rapid transport of a sample into or from magnetic field in permanent Halbach-type (1 T) or superconducting (4.7 T) magnets. Time dependence of induced changes of the sample temperature, ΔT(t), is detected directly by the differential Cu-Constantan-Cu micro-thermocouples with time steps of 300 ms. A sample placed inside an evacuated simple LN(2) cryostat is either totally isolated (adiabatic conditions) or partly connected with the copper sample holder (non-adiabatic conditions). The last arrangement (a model of the Brayton cycle) is used to simulate an application of MCE in refrigeration techniques. The relations describing ΔT(t) that allow an analysis of MCE of the studied materials are based on the general cooling law. The effect of the first-order magnetic transition on MCE of selected sample is also demonstrated by non-standard ΔT(t) curves measured in the last mentioned experimental arrangements.

  18. The effects of caloric stimulation of the labyrinth on the soleus motor pool in man.

    Science.gov (United States)

    Delwaide, P J; Juprelle, M

    1977-04-01

    The effects of caloric stimulation of the labyrinth on the soleus motor pool have been investigated using the Achilles tendon reflex, the H reflex, and the vibratory inhibition of the H reflex. The excitability of the myotatic reflex are is augmented from the beginning of irrigation and remains so until the end of nystagmus. The effects are bilateral and roughly symmetrical. The observed effects are due to simultaneous activation of non-specific, probably reticular, and specific, doubtless vestibular, , mechanisms. The Achilles tendon reflex is more facilitated than the H reflex, and the vibratory inhibition of the H reflex is not modified following irrigation of the ear canal. These results indicate a simultaneous facilitation of alpha and gamma extensor motoneurones but gamma effects clearly predominate. This interpretation is in good agreement with the findings of the animal neurophysiology. The vibratory inhibition argues against a modification of presynaptic inhibition. Before interpreting this fact as different from animal mechanisms, one must take into account the particular experimental conditions realized in man: the stimulus is complex and interactions between various nervous structures are possible.

  19. Entropy Generation and Human Aging: Lifespan Entropy and Effect of Diet Composition and Caloric Restriction Diets

    Directory of Open Access Journals (Sweden)

    Carlos A. Silva

    2009-01-01

    Full Text Available The first and second laws of thermodynamic were applied to statistical databases on nutrition and human growth in order to estimate the entropy generation over the human lifespan. The calculations were performed for the cases of variation in the diet composition and calorie restriction diets; and results were compared to a base case in which lifespan entropy generation was found to be 11 404 kJ/K per kg of body mass, predicting a lifespan of 73.78 and 81.61 years for the average male and female individuals respectively. From the analysis of the results, it was found that changes of diet % of fat and carbohydrates do not have a significant impact on predicted lifespan, while the diet % of proteins has an important effect. Reduction of diet protein % to the minimum recommended in nutrition literature yields an average increase of 3.3 years on the predicted lifespan. Changes in the calorie content of the diet also have an important effect, yielding a % increase in lifespan equal or higher than the % reduction in the diet caloric content. This correlates well experimental data on small mammal and insects, in which lifespan has been increased by diet restriction.

  20. Viral Interleukin-10 Expressed by Human Cytomegalovirus during the Latent Phase of Infection Modulates Latently Infected Myeloid Cell Differentiation ▿ †

    OpenAIRE

    Avdic, Selmir; Cao, John Z.; Cheung, Allen K.L.; Abendroth, Allison; Slobedman, Barry

    2011-01-01

    The human cytomegalovirus UL111A gene is expressed during latent and productive infections, and it codes for homologs of interleukin-10 (IL-10). We examined whether viral IL-10 expressed during latency altered differentiation of latently infected myeloid progenitors. In comparison to infection with parental virus or mock infection, latent infection with a virus in which the gene encoding viral IL-10 has been deleted upregulated cytokines associated with dendritic cell (DC) formation and incre...