WorldWideScience

Sample records for latente em montado

  1. Avaliação da competitividade da agricultura do Alentejo no âmbito do ecossistema montado

    Directory of Open Access Journals (Sweden)

    Rui Fragoso

    2009-03-01

    Full Text Available Neste estudo procede-se à avaliação sócioeconómica do ecossistema montado no Alentejo, em termos da viabilidade dos actuais sistemas de produção e dos efeitos da política agrícola na sua competitividade e sustentabilidade. A metodologia utilizada baseou-se na construção de matrizes de análise política. Em função dos níveis de rendimento e dos efeitos das medidas de política agrícola, os sistemas de produção são classificados em termos da sua contribuição real para o crescimento económico.This paper makes a socio-economic evaluation of the "Montado" ecosystem in Alentejo. It is study the viability of the agricultural systems and the effects of agricultural policy in their competitiveness and sustainability. It is used a Policy Analysis Matrix to evaluate the agricultural systems competitiveness and their economic efficiency. The agricultural systems are classified concerning their contribution for the economic growth, in function of income levels and policy effects.

  2. Nature vs. Nurture: the Making of the Montado Ecosystem

    Directory of Open Access Journals (Sweden)

    Paulo Miguel Pereira

    2003-12-01

    Full Text Available The southern Iberian Peninsula is dominated by a savannah-like ecosystem, the montado, which is a typically Mediterranean cultural adaptation to generally poor productive areas. Montados are exploited for three main uses: forestry, agriculture, and extensive grazing, in proportions that vary according to local conditions (more or less productive land and historical circumstances. Because these ecosystems occur over a large geographic area (they occupy some 6 million ha, biodiversity would be expected to vary among montados. However, differences in management practices may also influence species distribution. In this paper, we investigate differences in plant and bird species diversity among 60 montados distributed all across southern Portugal. The environmental variables studied included geographical coordinates, climatological data, soil type, and altitude. We also investigated agro-economic variables that could describe human activities at each site: animal husbandry (breeds, stock density, grazing rotation, etc., agriculture (fallow rotation frequency, use of fertilizers, etc., and forestry (cork harvesting, thinning, etc.. Finally, land-use type and metrics were assessed from rectified aerial photographs. Species richness among these two groups was not correlated, sites with high or low numbers of plant species not necessarily having high or low numbers of bird species. However, both plant and bird communities exhibited a similar pattern of species composition and turnover. This pattern was ecologically based, rather than a result of biological similarities between groups: direct gradient analyses and variance partitioning revealed strong correlations between species distribution and spatial gradients, namely longitude and latitude. In trying to distinguish anthropogenic from biophysical processes, we found that both were equally important as drivers of montado biodiversity. Plants and birds exhibited a similar ecological pattern, although

  3. Diversidade funcional em sistemas de montado: fluxo de nutrientes em Quercus rotundifolia Lam. Functional diversity in “montado” systems: nutrients fluxes in Quercus rotundifolia Lam.

    Directory of Open Access Journals (Sweden)

    J. D. Nunes

    2007-01-01

    Full Text Available Os componentes dos ciclos de nutrientes em montados de Quercus rotundifolia Lam., relacionados com a precipitação foram estudados na região de Évora, de Novembro de 1996 a Dezembro de 2000. A precipitação bruta, o gotejo a diferentes distâncias do tronco e o escorrimento ao longo do tronco das árvores foram quantificados de modo contínuo, sendo colhidas amostras semanalmente para se proceder à respectiva caracterização química. A quantidade de nutrientes transferidos para o solo através das diferentes soluções foi também determinada. Verificou-se um acréscimo da concentração das espécies iónicas no gotejo em relação à precipitação bruta, o qual foi ainda mais manifesto no escorrimento ao longo do tronco. Estudaram-se, igualmente, as características físico-químicas do solo sob e fora da influência da copa destas árvores, num montado relativamente esparso. Além disso, também se avaliou a quantidade das camadas orgânicas e a quantidade de nutrientes aí retidos. As características físicas e químicas do solo apresentaram, de um modo geral, uma diferenciação positiva em resultado da presença das árvores. Avaliou-se a taxa de mineralização de N nas áreas sob e fora da acção do coberto das árvores, tendo-se observado uma mais elevada disponibilidade deste nutriente nas áreas do sob coberto.Nutrient cycling in Quercus rotundifolia Lam. systems, regarding precipitation was studied at Évora (Southern Portugal, since November of 1996 until December of 2000. The amounts of gross rainfall, throughfall (at different distances from the tree trunk and stemflow were measured continuously and samples for chemical analysis were collected weekly. The concentration of nutrients was higher in the throughfall than in the gross rainfall, especially in the areas closer to the tree trunk. Nutrients transferred to soil, through bulk rainfall, throughfall and stemflow were quantified. The highest concentration of nutrients

  4. A Holistic Approach to the Evaluation of the Montado Ecosystem Using Proximal Sensors

    Directory of Open Access Journals (Sweden)

    João Serrano

    2018-02-01

    Full Text Available The Montado is a silvo-pastoral system characterized by open canopy woodlands with natural or cultivated grassland in the undercover and grazing animals. The aims of this study were to present several proximal sensors with potential to monitor relevant variables in the complex montado ecosystem and demonstrate their application in a case study designed to evaluate the effect of trees on the pasture. This work uses data collected between March and June 2016, at peak of dryland pasture production under typical Mediterranean conditions, in twenty four sampling points, half under tree canopy (UTC and half outside tree canopy (OTC. Correlations were established between pasture biomass and capacitance measured by a commercial probe and between pasture quality and normalized difference vegetation index (NDVI measured by a commercial active optical sensor. The interest of altimetric and apparent soil electrical conductivity maps as the first step in the implementation of precision agriculture projects was demonstrated. The use of proximal sensors to monitor soil moisture content, pasture photosynthetically active radiation and temperature helped to explain the influence of trees on pasture productivity and quality. The significant and strong correlations obtained between capacitance and pasture biomass and between NDVI and pasture nutritive value (in terms of crude protein, CP and neutral detergent fibre, NDF can make an important contribution to determination of key components of pasture productivity and quality and implementation of site-specific pasture management. Animal tracking demonstrated its potential to be an important tool for understanding the interaction between various factors and components that interrelate in the montado ecosystem and to support grazing management decisions.

  5. 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…

  6. Agroecology and the Sustainable Production of Food and Fiber: Emergy Evaluation of Agriculture in the Montado

    Science.gov (United States)

    The silvopastoral, agricultural system of the montado in Southern Portugal is an example of the self-organization of an agroecological system adapted to the climate and soil conditions of the Mediterranean basin. This system with its consistent production of food, fiber, and ecos...

  7. 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

  8. Estimativa do fluxo de calor latente pelo balanço de energia em cultivo protegido de pimentão

    Directory of Open Access Journals (Sweden)

    Cunha Antonio Ribeiro da

    2002-01-01

    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.

  9. Precisão na montagem em articulador em função do tipo de gesso e tratamento do modelo

    OpenAIRE

    Lopes, Luis Artur; Cezero, Leonardo; Mezzomo, Élio; Suzuki, Roberto

    2010-01-01

    O objetivo do presente estudo foi investigar a influência do tipo de gesso na precisão da montagem de modelos superiores secos e hidratados em articulador semi-ajustável. Neste estudo, 36 modelos de gesso pedra foram confeccionados e montados em articulador segundo as condições de seis grupos experimentais e de acordo com o tipo de gesso e o tempo de hidratação dos modelos: Grupo 1: modelos secos fixados com gesso pedra; Grupo 2: modelos secos f...

  10. Produção pecuária no montado: suínos Livestock production in the “montado”: pigs

    Directory of Open Access Journals (Sweden)

    J. T. Nunes

    2007-01-01

    Full Text Available A produção pecuária no montado alentejano é muito importante, ao nível da exploração e à escala regional. Baseia-se no sistema silvo-pastoril, com aproveitamento directo dos recursos alimentares naturais por raças autóctones. O porco alentejano é considerado o rei dos montados alentejanos, destaca-se no aproveitamento pecuário desta floresta de uso múltiplo. Na primeira metade do século passado a raça alentejana representava cerca de 50% do armentio suíno português. A intensificação dos sistemas de produção, agrícolas e pecuários, contribuiu para um decréscimo acentuado, da suinicultura extensiva tradicional. Em 1986 a população de suínos autóctones no Alentejo tinha decaído para cerca de 2% do total nacional. As raças locais, seja de porcos ou ruminantes tem conhecido recentemente uma notoriedade nova, quando se aliam os produtos delas derivados ao território, numa perspectiva de fileira. A evolução da PAC e a consciencialização para os problemas ambientais contribuíram para reenquadrar os sistemas silvopastoris e, particularmente, a montanheira numa óptica produtiva sustentável. A montanheira tradicional consiste na engorda de porcos, com idades de 14 a 18 meses, em regime de pastoreio durante o Outono e Inverno, nos sob-cobertos dos montados de azinho e sobro. A engorda tardia, fortemente amilácea, produz carcaças pesadas de 120 kg a 140 kg com grande adiposidade. Porém, com a desejável infiltração de gordura intermuscular. O maneio adequado, à optimização das características da carcaça e à aptidão tecnológica da carne e gordura nos sistemas silvo-pastoris, implica conhecer objectivamente: os recursos naturais, a fisiologia particular das raças locais, as características físicas químicas e sensoriais requeridas pelos produtos tradicionais e pela carne fresca.Livestock production in Alentejo has been very important considering both farm and general economy. It is based on natural

  11. Effect of stimulus intensity on latent inhibition: A case for generalization decrement

    Directory of Open Access Journals (Sweden)

    Gabriel Rodríguez

    2002-01-01

    Full Text Available En dos experimentos se empleó la técnica de aversión condicionada al sabor en ratas para examinar el efecto de la intensidad del estímulo expuesto sobre la inhibición latente. En el Experimento 1 se valoró el efecto de la exposición de un sabor dulce en distintas concentraciones sobre la tasa de adquisición de su condicionamiento posterior. Los resultados de este experimento mostraron un mayor efecto de inhibición latente tras la exposición del sabor en igual concentración a la empleada durante el condicionamiento (grupo EI que tras su exposición en una concentración mayor (grupo EM o menor (grupo Em. Además, esta atenuación del efecto de inhibición latente en las condiciones de cambio en la concentración resultó menor en el grupo EM que en el grupo Em. El Experimento 2 demostró que la generalización de las propiedades aversivas condicionadas al sabor fue mayor entre las concentraciones empleadas en el grupo EM que en el grupo Em. Estos resultados sugieren que el aparente efecto de la intensidad del estímulo en la inhibición latente podría ser explicado en términos de decremento en la generalización.

  12. Transcriptional Regulation of Latent Feline Immunodeficiency Virus in Peripheral CD4+ T-lymphocytes

    Directory of Open Access Journals (Sweden)

    Brian G. Murphy

    2012-05-01

    Full Text Available Feline immunodeficiency virus (FIV, the lentivirus of domestic cats responsible for feline AIDS, establishes a latent infection in peripheral blood CD4+ T-cells approximately eight months after experimental inoculation. In this study, cats experimentally infected with the FIV-C strain in the asymptomatic phase demonstrated an estimated viral load of 1 infected cell per approximately 103 CD4+ T-cells, with about 1 copy of viral DNA per cell. Approximately 1 in 10 proviral copies was capable of transcription in the asymptomatic phase. The latent FIV proviral promoter was associated with deacetylated, methylated histones, which is consistent with a condensed chromatin structure. In contrast, the transcriptionally active FIV promoter was associated with histone acetylation and demethylation. In addition, RNA polymerase II appeared to be paused on the latent viral promoter, and short promoter-proximal transcripts were detected. Our findings for the FIV promoter in infected cats are similar to results obtained in studies of human immunodeficiency virus (HIV-1 latent proviruses in cell culture <em>in vitroem> studies. Thus, the FIV/cat model may offer insights into <em>in vivoem> mechanisms of HIV latency and provides a unique opportunity to test novel therapeutic interventions aimed at eradicating latent virus.

  13. Inovação em serviços : estudo de casos em uma organização da indústria hoteleira brasileira

    OpenAIRE

    Claudia Fernanda Franceschi Klement

    2007-01-01

    Dentre as estratégias utilizadas pelas organizações, inclusive prestadoras de serviço, no intuito de fazer frente à concorrência e manter-se competitivas no mercado, encontra-se a busca constante da inovação. Muito já se estudou sobre inovação em indústrias manufatureiras. Utterback (1994) estudou diferentes indústrias, incluindo as de bens não-montados (como o vidro), no intuito de compreender como se dá o processo de inovação e como acontece o design dominante. Henderson e Clark (1990) busc...

  14. 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...

  15. Infecção aguda e latente em ovinos inoculados com o herpesvírus bovino tipo 5 (BHV-5

    Directory of Open Access Journals (Sweden)

    Silva Adriana M.

    1998-01-01

    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

  16. Steam sterilization of previously-assembled laparoscopic instruments Esterilización por vapor de los instrumentos laparoscópicos previamente armados Esterilização pelo vapor dos instrumentos laparoscópicos previamente montados

    Directory of Open Access Journals (Sweden)

    Tamara Carolina de Camargo

    2008-01-01

    permitieron conclusiones favorables para la práctica del autoclado de los instrumentos laparoscópicos previamente armados. En el estudio que investigó exactamente el asunto de la investigación encontró contaminación después de la esterilización, tanto en instrumentos armados (1/24 como en los desarmados (1/30, demostrando equivalencia de riesgo. Frente a los resultados, y considerando la escasez de trabajos al respecto, se recomienda un nuevo estudio experimental de laboratorio randomizado utilizando contaminación desafío.A vídeo-laparoscopia representa um dos maiores avanços na área da cirurgia nos últimos tempos. Os instrumentos laparoscópicos reprocessáveis são artigos complexos, que se esterilizados totalmente desmontados trazem transtornos às equipes cirúrgicas no momento da sua utilização no campo operatório. O método de escolha para a esterilização desses instrumentos é o vapor saturado sob pressão. O objetivo dessa revisão foi descrever o estado da arte em busca dos resultados da segurança na autoclavação do instrumental laparoscópico reprocessável, previamente montado, tendo em vista as dificuldades de montagem deles no momento da cirurgia. Foi consultada a base de dados PUBMED, usando vocábulos controlados, livres e a combinação deles, sem restrição de tempo e idioma. Foram localizados apenas dois artigos que permitiram conclusões favoráveis para a prática de autoclavar os instrumentos laparoscópicos previamente montados. O estudo que investigou exatamente a questão da pesquisa encontrou contaminação após a esterilização, tanto em instrumentos montados (1/24 como nos desmontados (1/30, demonstrando equivalência do risco. Frente aos resultados, e considerando a escassez de trabalhos sobre o assunto, recomenda-se um novo estudo experimental laboratorial randomizado utilizando contaminação desafio.

  17. Análise morfométrica de impressões palmares latentes em função do tempo : uma contribuição para a prática forense

    OpenAIRE

    Barros, Rodrigo Meneses de

    2013-01-01

    Em inúmeros crimes, o lapso temporal transcorrido entre a produção e a coleta de vestígios papilares é fundamental. Uma impressão latente é produzida quando as cristas de fricção, presentes na epiderme da pele espessa, entram em contato com uma superfície. Por conseguinte, gotículas dos compostos secretados pelas glândulas da pele sofrem degradação, afetando a morfologia e a técnica para revelação das impressões. O presente trabalho teve por objetivo inv...

  18. Um objeto-modelo didático do movimento aparente do Sol em relação ao fundo de estrelas

    Directory of Open Access Journals (Sweden)

    Francisco Catelli

    2013-04-01

    “Por que o Sol nunca passa pela constelação de Órion?” A resposta a essa pergunta, feita por um aluno, inicia com uma revisão da literatura sobre modelos, em especial aqueles relacionados aos objetos-modelo didáticos. A pergunta é respondida, então, inicialmente, usando um mapa do céu, o qual é, em seguida, transformado em um cilindro, e este, por sua vez, é montado em um dispositivo didático de modo a materializar o movimento aparente da abóbada celeste, em uma latitude escolhida, constituindo-se, assim, em um verdadeiro “mini planetário”. Contudo, para chegar a um nível de resposta que inclua conceitos como o da vertical do lugar, a invariância da orientação do eixo de rotação da Terra, o equador celeste e a eclíptica, fazem-se necessários outros modelos. Por fim, conclui-se que não é apenas um, mas sim um conjunto articulado de modelos que pode levar a uma resposta aceitável à questão proposta.

  19. 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

  20. Tratamento da tuberculose de infecção latente: As recomendações actuais Latent tuberculosis infection treatment: Current recommendations

    Directory of Open Access Journals (Sweden)

    R Duarte

    2010-09-01

    Full Text Available O diagnóstico e tratamento da infecção latente por Mycobacterium tuberculosis reduz significativamente o risco de desenvolvimento de tuberculose activa e a transmissão da doença na comunidade. O rastreio da tuberculose infecção latente deve passar pela exclusão de doença activa (inquérito de sintomas e radiografia pulmonar e avaliação da resposta imunológica ao M. tuberculosis através dos testes actualmente ao dispor, como o teste tuberculínico e os testes IGRA (interferon-gamma release assay. A escolha do esquema de tratamento deve ter em linha de conta a eficácia, a adesão e os efeitos colaterais associados ao mesmo Este documento actualiza as recomendações sobre tratamento da tuberculose infecção latente. São apresentadas indicações sobre quem deve ser rastreado e revistos os esquemas de tratamento.Diagnosis and treatment of latent infection with Mycobacterium tuberculosis (LTBI, significantly reduces the risk of developing active tuberculosis and the transmission of the disease in the community. LTBI screening must pass by the exclusion of active disease (symptoms enquiry and chest radiography and assessment of immune response to Mycobacterium tuberculosis testing with the tests currently available - tuberculin skin test and interferon-gamma release assay (IGRA. The choice of treatment must take into account the efficacy and side effects associated with the same. This document provides updated recommendations on latent tuberculosis infection treatment. Topics covered include whom to test for TB and reviewed LTBI treatment regimens.

  1. 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.

  2. Inverse Ising problem in continuous time: A latent variable approach

    Science.gov (United States)

    Donner, Christian; Opper, Manfred

    2017-12-01

    We consider the inverse Ising problem: the inference of network couplings from observed spin trajectories for a model with continuous time Glauber dynamics. By introducing two sets of auxiliary latent random variables we render the likelihood into a form which allows for simple iterative inference algorithms with analytical updates. The variables are (1) Poisson variables to linearize an exponential term which is typical for point process likelihoods and (2) Pólya-Gamma variables, which make the likelihood quadratic in the coupling parameters. Using the augmented likelihood, we derive an expectation-maximization (EM) algorithm to obtain the maximum likelihood estimate of network parameters. Using a third set of latent variables we extend the EM algorithm to sparse couplings via L1 regularization. Finally, we develop an efficient approximate Bayesian inference algorithm using a variational approach. We demonstrate the performance of our algorithms on data simulated from an Ising model. For data which are simulated from a more biologically plausible network with spiking neurons, we show that the Ising model captures well the low order statistics of the data and how the Ising couplings are related to the underlying synaptic structure of the simulated network.

  3. El gobierno del caballo montado en la antigüedad clásica con especial referencia al caso de Iberia. Bocados, espuelas y la cuestión de la silla de montar, estribos y herraduras

    Directory of Open Access Journals (Sweden)

    Quesada Sanz, Fernando

    2005-12-01

    Full Text Available We examine the different elements of the horse’s tack in Antiquity: bits, spurs, saddle, stirrups and the problem of horseshoes, with special reference to the case of Iberia.

    Se analizan los elementos de control del caballo montado en la Antigüedad: bocados, espuelas, silla y estribos, y se hace referencia al problema de las herraduras, todo ello con especial referencia al caso de la antigua Iberia.

  4. As relações de trabalho em uma empresa global: um novo paradigma ou neocorporativismo?

    Directory of Open Access Journals (Sweden)

    Arnaldo José França Mazzei Nogueira

    Full Text Available Este artigo trata das relações de trabalho em uma empresa global e foi resultado de pesquisa em uma montadora de caminhões instalada na região do ABC no Estado de São Paulo, Brasil. A empresa estudada apresenta um padrão dos mais avançados na dimensão organizacional das relações de trabalho ou no local de trabalho considerado o contexto brasileiro. A solução de conflitos do trabalho nesta empresa aponta fortemente para um padrão negocial em relação ao estatutário (Zylberstajn e Pastore, 1985, o que levou alguns autores a indicar um modo de cooperação-conflitiva para lidar com as relações de trabalho (Rodrigues, 1997 e uma via institucionalizada de inserção dos trabalhadores nos processos de inovação tecnológica e gerencial (Bresciani, 2002. O esquema montado dentro da empresa foi resultado da estratégia do sindicato no local de trabalho e da gestão da empresa em particular da gestão de recursos humanos. A análise da experiência permitiu verificar além de um paradigma avançado de relações de trabalho, a afirmação de uma tendência ao corporativismo societário ou neo-corporativismo em relação ao corporativismo estatal típico do sistema trabalhista brasileiro.

  5. Latent heat coldness storage; Stockage du froid par chaleur latente

    Energy Technology Data Exchange (ETDEWEB)

    Dumas, J.P. [Pau Univ., Lab. de Thermodynamique et Energetique, LTE, 64 (France)

    2002-07-01

    This article presents the advantages of latent heat storage systems which use the solid-liquid phase transformation of a pure substance or of a solution. The three main methods of latent heat storage of coldness are presented: ice boxes, encapsulated nodules, and ice flows: 1 - definition of the thermal energy storage (sensible heat, latent heat, thermochemical storage); 2 - advantages and drawbacks of latent heat storage; 3 - choice criteria for a phase-change material; 4 - phenomenological aspect of liquid-solid transformations (phase equilibrium, crystallisation and surfusion); 5 - different latent heat storage processes (ice boxes, encapsulated nodules, two-phase refrigerating fluids); 6 - ice boxes (internal and external melting, loop, air injection, measurement of ice thickness); 7 - encapsulated nodules (nodules, tank, drainage, advantage and drawbacks, charge and discharge); 8 - two-phase refrigerating fluids (composition, ice fabrication, flow circulation, flow storage, exchangers). (J.S.)

  6. 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.

  7. Latent palmprint matching.

    Science.gov (United States)

    Jain, Anil K; Feng, Jianjiang

    2009-06-01

    The evidential value of palmprints in forensic applications is clear as about 30 percent of the latents recovered from crime scenes are from palms. While biometric systems for palmprint-based personal authentication in access control type of applications have been developed, they mostly deal with low-resolution (about 100 ppi) palmprints and only perform full-to-full palmprint matching. We propose a latent-to-full palmprint matching system that is needed in forensic applications. Our system deals with palmprints captured at 500 ppi (the current standard in forensic applications) or higher resolution and uses minutiae as features to be compatible with the methodology used by latent experts. Latent palmprint matching is a challenging problem because latent prints lifted at crime scenes are of poor image quality, cover only a small area of the palm, and have a complex background. Other difficulties include a large number of minutiae in full prints (about 10 times as many as fingerprints), and the presence of many creases in latents and full prints. A robust algorithm to reliably estimate the local ridge direction and frequency in palmprints is developed. This facilitates the extraction of ridge and minutiae features even in poor quality palmprints. A fixed-length minutia descriptor, MinutiaCode, is utilized to capture distinctive information around each minutia and an alignment-based minutiae matching algorithm is used to match two palmprints. Two sets of partial palmprints (150 live-scan partial palmprints and 100 latent palmprints) are matched to a background database of 10,200 full palmprints to test the proposed system. Despite the inherent difficulty of latent-to-full palmprint matching, rank-1 recognition rates of 78.7 and 69 percent, respectively, were achieved in searching live-scan partial palmprints and latent palmprints against the background database.

  8. Estudo da viabilidade do preparo direto para descanso de cíngulo em incisivo central superior

    Directory of Open Access Journals (Sweden)

    ALENCAR José Freire de

    2000-01-01

    Full Text Available Esta pesquisa teve como finalidade estudar a viabilidade do preparo direto para descanso em cíngulo de incisivo central superior, por intermédio de processamento de imagem. Foram reproduzidos dez dentes íntegros, montados em um suporte de alumínio com resina acrílica e distribuídos entre cinco especialistas, que executaram os preparos para descanso. Em seguida, os corpos-de-prova foram cortados ao longo de suas coroas, tendo como guia um corte inicial, feito no centro da borda incisal de cada dente. O preparo foi então dimensionado, estabelecendo-se medidas lineares e angulares que permitissem uma análise comparativa entre o perfil original do dente e aquele após o preparo, enquanto se determinava a perfuração ou não da camada de esmalte. Todas as observações foram feitas, digitalizando-se os perfis e processando as imagens num programa específico. Dos cinqüenta modelos preparados, seguindo critérios estabelecidos, trinta e três perfuraram a camada de esmalte. Sendo assim, o incisivo central superior não está indicado para receber preparo direto para descanso de cíngulo.

  9. α4β7+ CD4+ Effector/Effector Memory T Cells Differentiate into Productively and Latently Infected Central Memory T Cells by Transforming Growth Factor β1 during HIV-1 Infection.

    Science.gov (United States)

    Cheung, Ka-Wai; Wu, Tongjin; Ho, Sai Fan; Wong, Yik Chun; Liu, Li; Wang, Hui; Chen, Zhiwei

    2018-04-15

    HIV-1 transmission occurs mainly through mucosal tissues. During mucosal transmission, HIV-1 preferentially infects α 4 β 7 + gut-homing CCR7 - CD4 + effector/effector memory T cells (T EM ) and results in massive depletion of these cells and other subsets of T EM in gut-associated lymphoid tissues. However, besides being eliminated by HIV-1, the role of T EM during the early stage of infection remains inconclusive. Here, using in vitro -induced α 4 β 7 + gut-homing T EM (α 4 β 7 + T EM ), we found that α 4 β 7 + T EM differentiated into CCR7 + CD4 + central memory T cells (T CM ). This differentiation was HIV-1 independent but was inhibited by SB431542, a specific transforming growth factor β (TGF-β) receptor I kinase inhibitor. Consistently, T EM -to-T CM differentiation was observed in α 4 β 7 + T EM stimulated with TGF-β1 (TGF-β). The T CM properties of the TGF-β-induced T EM -derived T CM (α 4 β 7 + T CM ) were confirmed by their enhanced CCL19 chemotaxis and the downregulation of surface CCR7 upon T cell activation in vitro Importantly, the effect of TGF-β on T CM differentiation also held in T EM directly isolated from peripheral blood. To investigate the significance of the TGF-β-dependent T EM -to-T CM differentiation in HIV/AIDS pathogenesis, we observed that both productively and latently infected α 4 β 7 + T CM could differentiate from α 4 β 7 + T EM in the presence of TGF-β during HIV-1 infection. Collectively, this study not only provides a new insight for the plasticity of T EM but also suggests that the TGF-β-dependent T EM -to-T CM differentiation is a previously unrecognized mechanism for the formation of latently infected T CM after HIV-1 infection. IMPORTANCE HIV-1 is the causative agent of HIV/AIDS, which has led to millions of deaths in the past 30 years. Although the implementation of highly active antiretroviral therapy has remarkably reduced the HIV-1-related morbidity and mortality, HIV-1 is not eradicated in

  10. Latent-trait latent-class analysis of selfdisclosure in the work environment

    NARCIS (Netherlands)

    Maij - de Meij, A.M.; Kelderman, H.; van der Flier, H.

    2006-01-01

    Based on the literature about self-disclosure, it was hypothesized that different groups of subjects differ in their pattern of self-disclosure with respect to different areas of social interaction. An extended latent-trait latent-class model was proposed to describe these general patterns of

  11. Latent-trait latent-class analysis of selfdisclosure in the work environment

    NARCIS (Netherlands)

    Maij - de Meij, A.M.; Kelderman, H.; van der Flier, H.

    2005-01-01

    Based on the literature about self-disclosure, it was hypothesized that different groups of subjects differ in their pattern of self-disclosure with respect to different areas of social interaction. An extended latent-trait latent-class model was proposed to describe these general patterns of

  12. Significados latentes na fotografia em turismo: o caso do turismo negro na Costa Morte (Galiza

    Directory of Open Access Journals (Sweden)

    Antonio Azevedo

    2017-01-01

    Full Text Available To what extent can a photograph be a representation of the identity of a place, spread emotions, simulate / emulate experiences and motivate the visit to the destination? This study seeks to explore the fascination (gaze, the influence of landscape interpretation, the perception of authenticity, the psychological density associated with images of black tourism? What elements and symbols are possible in an explicit or latent way? What is the role of the tourist in the co ‑ creation of the image of destiny? This study has as its starting point and unit of analysis the intangible heritage and the “aura” emanated by various places and landscapes of the Costa da Morte (Coast of Death in Galicia spiced by the legends and mythology of a rich in events historical past. Using a methodological approach that included qualitative selection and analysis of photographs, documentaries and books, direct observation, passive netnography and photo elicitation several latent content elements or classification categories were proposed.

  13. Seleção de genótipos de cana-de-açúcar para acúmulo de protoporfirina ix com uso de herbicidas inibidores da protox

    OpenAIRE

    Barberis,L.R.M.; Trindade,M.L.B.; Velini,E.D.

    2009-01-01

    O objetivo do presente trabalho foi selecionar genótipos de cana-de-açúcar por meio de inibidores da PROTOX e antioxidantes para indução do acúmulo de protoporfirina IX (PROTO IX) e/ou de seus precursores em plantas. Esses compostos podem ser utilizados como agentes sensibilizantes em terapia fotodinâmica (TFD), os quais possibilitam uma fonte de baixo custo para o tratamento de neoplasias e carcinomas. O experimento foi montado em câmara climatizada, com aplicação de nove tratamentos (1. oxy...

  14. Latent-Trait Latent-Class Analysis of Self-disclosure in the Work Environment

    NARCIS (Netherlands)

    Maij - de Meij, A.M.; Kelderman, H.; van der Flier, H.

    2005-01-01

    Based on the literature about self-disclosure, it was hypothesized that different groups of subjects differ in their pattern of self-disclosure with respect to different areas of social interaction. An extended latent-trait latent-class model was proposed to describe these general patterns of

  15. Latent classification models

    DEFF Research Database (Denmark)

    Langseth, Helge; Nielsen, Thomas Dyhre

    2005-01-01

    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....

  16. The Latent Structure of Autistic Traits: A Taxometric, Latent Class and Latent Profile Analysis of the Adult Autism Spectrum Quotient

    Science.gov (United States)

    James, Richard J.; Dubey, Indu; Smith, Danielle; Ropar, Danielle; Tunney, Richard J.

    2016-01-01

    Autistic traits are widely thought to operate along a continuum. A taxometric analysis of Adult Autism Spectrum Quotient data was conducted to test this assumption, finding little support but identifying a high severity taxon. To understand this further, latent class and latent profile models were estimated that indicated the presence of six…

  17. SEGUINDO OS PASSOS DE SHERLOCK HOLMES: EXPERIÊNCIA INTERDISCIPLINAR EM ENCONTRO DE DIVULGAÇÃO CIENTÍFICA

    Directory of Open Access Journals (Sweden)

    Anelise Maria Regiani

    Full Text Available Um dos aspectos da inclusão social é a possibilidade de o cidadão ter a oportunidade de adquirir conhecimento básico sobre a ciência e seu funcionamento. Nesse sentido, a realização de eventos de divulgação científica é estratégia importante na perspectiva da alfabetização científica. O presente trabalho pretende analisar uma atividade na qual os participantes foram convidados a desvendar a dinâmica de um crime fictício a partir da investigação do local do crime montado por peritos criminais. Apesar de não ter sido concebida como tal, pode-se afirmar que a atividade utilizou a metodologia de ilha interdisciplinar de racionalidade de Fourez. Os distanciamentos metodológicos detectados foram consequências da inserção dessa atividade em evento de divulgação científica.

  18. Prevalence of latent Mycobacterium tuberculosis infection in prisoners.

    Science.gov (United States)

    Navarro, Pedro Daibert de; Almeida, Isabela Neves de; Kritski, Afrânio Lineu; Ceccato, Maria das Graças; Maciel, Mônica Maria Delgado; Carvalho, Wânia da Silva; Miranda, Silvana Spindola de

    2016-01-01

    To determine the prevalence of and the factors associated with latent Mycobacterium tuberculosis infection (LTBI) in prisoners in the state of Minas Gerais, Brazil. This was a cross-sectional cohort study conducted in two prisons in Minas Gerais. Tuberculin skin tests were performed in the individuals who agreed to participate in the study. A total of 1,120 individuals were selected for inclusion in this study. The prevalence of LTBI was 25.2%. In the multivariate analysis, LTBI was associated with self-reported contact with active tuberculosis patients within prisons (adjusted OR = 1.51; 95% CI: 1.05-2.18) and use of inhaled drugs (adjusted OR = 1.48; 95% CI: 1.03-2.13). Respiratory symptoms were identified in 131 (11.7%) of the participants. Serological testing for HIV was performed in 940 (83.9%) of the participants, and the result was positive in 5 (0.5%). Two cases of active tuberculosis were identified during the study period. Within the prisons under study, the prevalence of LTBI was high. In addition, LTBI was associated with self-reported contact with active tuberculosis patients and with the use of inhaled drugs. Our findings demonstrate that it is necessary to improve the conditions in prisons, as well as to introduce strategies, such as chest X-ray screening, in order to detect tuberculosis cases and, consequently, reduce M. tuberculosis infection within the prison system. Determinar a prevalência e os fatores associados à infecção latente por Mycobacterium tuberculosis (ILTB) em pessoas privadas de liberdade no Estado de Minas Gerais. Estudo de coorte transversal realizado em duas penitenciárias em Minas Gerais. Foi realizada a prova tuberculínica nos indivíduos que aceitaram participar do estudo. Foram selecionados 1.120 indivíduos para a pesquisa. A prevalência da ILTB foi de 25,2%. Na análise multivariada, a ILTB esteve associada com relato de contato com caso de tuberculose ativa dentro da penitenciária (OR ajustada = 1,51; IC95%: 1

  19. Latent-Trait Latent-Class Analysis of Self-Disclosure in the Work Environment

    Science.gov (United States)

    Maij-de Meij, Annette M.; Kelderman, Henk; van der Flier, Henk

    2005-01-01

    Based on the literature about self-disclosure, it was hypothesized that different groups of subjects differ in their pattern of self-disclosure with respect to different areas of social interaction. An extended latent-trait latent-class model was proposed to describe these general patterns of self-disclosure. The model was used to analyze the data…

  20. High-Performance Psychometrics: The Parallel-E Parallel-M Algorithm for Generalized Latent Variable Models. Research Report. ETS RR-16-34

    Science.gov (United States)

    von Davier, Matthias

    2016-01-01

    This report presents results on a parallel implementation of the expectation-maximization (EM) algorithm for multidimensional latent variable models. The developments presented here are based on code that parallelizes both the E step and the M step of the parallel-E parallel-M algorithm. Examples presented in this report include item response…

  1. Modeling Nonlinear Change via Latent Change and Latent Acceleration Frameworks: Examining Velocity and Acceleration of Growth Trajectories

    Science.gov (United States)

    Grimm, Kevin; Zhang, Zhiyong; Hamagami, Fumiaki; Mazzocco, Michele

    2013-01-01

    We propose the use of the latent change and latent acceleration frameworks for modeling nonlinear growth in structural equation models. Moving to these frameworks allows for the direct identification of "rates of change" and "acceleration" in latent growth curves--information available indirectly through traditional growth…

  2. Paisajes montados

    OpenAIRE

    Mastricchio, Malena Mazzitelli

    2016-01-01

    Como parte de un proyecto de investigación doctoral sobre las prácticas y los insumos visuales que los topógrafos usaron para diseñar hojas topográficas en la Dirección de Minas y Geología e Hidrología en la primera mitad del siglo XX, esta Tesis de Doctorado en Geografía en la Universidad de Buenos Aires propone analizar los aspectos sensibles, artísticos, estéticos e incluso personales que son constitutivos del lenguaje cartográfico formalizado para la representación de la topografía – aunq...

  3. Notas sobre a liberdade e a tirania da maioria em Stuart Mill

    Directory of Open Access Journals (Sweden)

    Antonio Ozaí da Silva

    2009-10-01

    Full Text Available O liberalismo é uma doutrina política que, em suas origens, tem como alicerce vários autores clássicos do pensamento político: Locke, Montesquieu, Kant, Adam Smith, Humboldt, Benjamin Constant, Alexis de Tocqueville, Stuart Mil e outros. Portanto, a exemplo do socialismo, cabe perfeitamente a pergunta: Qual liberalismo? Como o(s marxismo(s, o pensamento liberal não é homogêneo. Da mesma forma, o conceito de liberdade no pensamento liberal tem mais de uma conotação, como também a sua crítica. Estes apontamentos se limitam a expor o pensamento político de John Stuart Mill, mais precisamente sobre a sua argumentação em defesa da liberdade individual e a crítica à tirania da maioria no ensaio <em>“Sobre a Liberdade”em> (MILL, 1991.

  4. Tratamento da tuberculose de infecção latente. As recomendações actuais

    Directory of Open Access Journals (Sweden)

    R. Duarte

    2010-09-01

    Full Text Available Resumo: O diagnóstico e tratamento da infecção latente por Mycobacterium tuberculosis reduz significativamente o risco de desenvolvimento de tuberculose activa e a transmissão da doença na comunidade. O rastreio da tuberculose infecção latente deve passar pela exclusão de doença activa (inquérito de sintomas e radiografia pulmonar e avaliação da resposta imunológica ao M. tuberculosis através dos testes actualmente ao dispor, como o teste tuberculínico e os testes IGRA (interferon-gamma release assay. A escolha do esquema de tratamento deve ter em linha de conta a eficácia, a adesão e os efeitos colaterais associados ao mesmo Este documento actualiza as recomendações sobre tratamento da tuberculose infecção latente. São apresentadas indicações sobre quem deve ser rastreado e revistos os esquemas de tratamento. Abstract: Diagnosis and treatment of latent infection with Mycobacterium tuberculosis (LTBI, significantly reduces the risk of developing active tuberculosis and the transmission of the disease in the community. LTBI screening must pass by the exclusion of active disease (symptoms enquiry and chest radiography and assessment of immune response to Mycobacterium tuberculosis testing with the tests currently available – tuberculin skin test and interferon-gamma release assay (IGRA. The choice of treatment must take into account the efficacy and side effects associated with the same. This document provides updated recommendations on latent tuberculosis infection treatment. Topics covered include whom to test for TB and reviewed LTBI treatment regimens. Palavras-chave: Tuberculose, tuberculose infeccao latente, tratamento, preventivo, Key words: Tuberculosis, latent tuberculosis infection, treatment, preventive

  5. Longitudinal Research with Latent Variables

    CERN Document Server

    van Montfort, Kees; Satorra, Albert

    2010-01-01

    This book combines longitudinal research and latent variable research, i.e. it explains how longitudinal studies with objectives formulated in terms of latent variables should be carried out, with an emphasis on detailing how the methods are applied. Because longitudinal research with latent variables currently utilizes different approaches with different histories, different types of research questions, and different computer programs to perform the analysis, the book is divided into nine chapters. Starting from some background information about the specific approach, short history and the ma

  6. TAXA DE PREDAÇÃO DE NINHOS ARTIFICIAIS EM UMA ÁREA DE MANEJO FLORESTAL SUSTENTÁVEL NA AMAZÔNIA CENTRAL

    Directory of Open Access Journals (Sweden)

    Roberta Souza de Moura

    2017-01-01

    Full Text Available A predação de ninhos vem sendo sugerida como uma das causas do declínio de populações de aves, influenciando a estrutura e funcionamento das comunidades.  Apesar de diversos estudos terem avaliado fatores relacionados às variações nas taxas de predação de ninhos, poucos verificaram os efeitos do manejo florestal sustentável sobre estas taxas. O presente trabalho teve como objetivo avaliar a influência do manejo florestal sustentável sobre a taxa de predação de ninhos artificiais em uma floresta de terra firme na Amazônia Central. Para isso foram instalados ninhos artificiais em três áreas entre 11/2014 e 06/2015. Dos 240 ninhos montados 72 foram predados, sendo 29 na área não manejada, 24 na Área de Preservação Permanente e 19 na área manejada. Dos 72 ninhos predados 55,56% foram ninhos de sub-bosque e 44,44% ninhos de solo. A menor taxa de predação na área manejada pode estar relacionada às alterações na estrutura da vegetação e ao consequente afugentamento dos predadores.

  7. Automação de um sistema de pulverização para aplicação de agroquímicos a taxa variada usando injeção direta

    OpenAIRE

    Heitor Vinicius Mercaldi

    2012-01-01

    Neste trabalho, a automação de um sistema de pulverização a taxa variada com injeção direta é apresentado. A automação do sistema de pulverização montado em uma bancada laboratorial estática foi baseado em um controlador programável com capacidade de tempo real. Os sistemas de pulverização com injeção direta possibilitam o uso de diferentes agroquímicos em uma mesma aplicação, e adicionalmente reduzem os impactos toxicológico e ambiental relacionados com o preparo e descarte da mistura de agr...

  8. Tratamento da tuberculose de infecção latente. As recomendações actuais

    Directory of Open Access Journals (Sweden)

    R. Duarte

    2010-09-01

    Full Text Available Resumo: O diagnóstico e tratamento da infecção latente por Mycobacterium tuberculosis reduz significativamente o risco de desenvolvimento de tuberculose activa e a transmissão da doença na comunidade. O rastreio da tuberculose infecção latente deve passar pela exclusão de doença activa (inquérito de sintomas e radiografia pulmonar e avaliação da resposta imunológica ao M. tuberculosis através dos testes actualmente ao dispor, como o teste tuberculínico e os testes IGRA (interferon-gamma release assay. A escolha do esquema de tratamento deve ter em linha de conta a eficácia, a adesão e os efeitos colaterais associados ao mesmo Este documento actualiza as recomendações sobre tratamento da tuberculose infecção latente. São apresentadas indicações sobre quem deve ser rastreado e revistos os esquemas de tratamento.Rev Port Pneumol 2010; XVI (5: 809-814 Abstract: Diagnosis and treatment of latent infection with Mycobacterium tuberculosis (LTBI, significantly reduces the risk of developing active tuberculosis and the transmission of the disease in the community. LTBI screening must pass by the exclusion of active disease (symptoms enquiry and chest radiography and assessment of immune response to Mycobacterium tuberculosis testing with the tests currently available – tuberculin skin test and interferon-gamma release assay (IGRA. The choice of treatment must take into account the efficacy and side effects associated with the same. This document provides updated recommendations on latent tuberculosis infection treatment. Topics covered include whom to test for TB and reviewed LTBI treatment regimens.Rev Port Pneumol 2010; XVI (5: 809-814 Palavras-chave: Tuberculose, tuberculose infecção latente, tratamento, preventivo, Key words: Tuberculosis, latent tuberculosis infection, treatment, preventive

  9. 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...... logit model suggests significant changes in the price sensitivity and the utility from environmental claims between both experimental waves. A pooled scale adjusted latent class model is estimated jointly over both waves and the relative size of latent classes is compared across waves, resulting...... in significant differences in the size of two out of seven classes. These differences can largely be accounted for by the changes on the aggregated level. The relative size of latent classes is correlated at 0.52, suggesting a fair robustness. An ex-post characterisation of latent classes by behavioural...

  10. On the Latent Variable Interpretation in Sum-Product Networks.

    Science.gov (United States)

    Peharz, Robert; Gens, Robert; Pernkopf, Franz; Domingos, Pedro

    2017-10-01

    One of the central themes in Sum-Product networks (SPNs) is the interpretation of sum nodes as marginalized latent variables (LVs). This interpretation yields an increased syntactic or semantic structure, allows the application of the EM algorithm and to efficiently perform MPE inference. In literature, the LV interpretation was justified by explicitly introducing the indicator variables corresponding to the LVs' states. However, as pointed out in this paper, this approach is in conflict with the completeness condition in SPNs and does not fully specify the probabilistic model. We propose a remedy for this problem by modifying the original approach for introducing the LVs, which we call SPN augmentation. We discuss conditional independencies in augmented SPNs, formally establish the probabilistic interpretation of the sum-weights and give an interpretation of augmented SPNs as Bayesian networks. Based on these results, we find a sound derivation of the EM algorithm for SPNs. Furthermore, the Viterbi-style algorithm for MPE proposed in literature was never proven to be correct. We show that this is indeed a correct algorithm, when applied to selective SPNs, and in particular when applied to augmented SPNs. Our theoretical results are confirmed in experiments on synthetic data and 103 real-world datasets.

  11. Wildfire patterns and landscape changes in Mediterranean oak woodlands.

    Science.gov (United States)

    Guiomar, N; Godinho, S; Fernandes, P M; Machado, R; Neves, N; Fernandes, J P

    2015-12-01

    Fire is infrequent in the oak woodlands of southern Portugal (montado) but large and severe fires affected these agro-forestry systems in 2003-2005. We hypothesised transition from forest to shrubland as a fire-driven process and investigated the links between fire incidence and montado change to other land cover types, particularly those related with the presence of pioneer communities (generically designed in this context as "transitions to early-successional communities"). We present a landscape-scale framework for assessing the probability of transition from montado to pioneer communities, considering three sets of explanatory variables: montado patterns in 1990 and prior changes from montado to early-successional communities (occurred between 1960 and 1990), fire patterns, and spatial factors. These three sets of factors captured 78.2% of the observed variability in the transitions from montado to pioneer vegetation. The contributions of fire patterns and spatial factors were high, respectively 60.6% and 43.4%, the influence of montado patterns and former changes in montado being lower (34.4%). The highest amount of explained variation in the occurrence of transitions from montado to early-successional communities was related to the pure effect of fire patterns (19.9%). Low spatial connectedness in montado landscape can increase vulnerability to changes, namely to pioneer vegetation, but the observed changes were mostly explained by fire characteristics and spatial factors. Among all metrics used to characterize fire patterns and extent, effective mesh size provided the best modelling results. Transitions from montado to pioneer communities are more likely in the presence of high values of the effective mesh size of total burned area. This cross-boundary metric is an indicator of the influence of large fires in the distribution of the identified transitions and, therefore, we conclude that the occurrence of large fires in montado increases its probability of

  12. 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....

  13. UNSOLVED AND LATENT CRIME: DIFFERENCES AND SIMILARITIES

    Directory of Open Access Journals (Sweden)

    Mikhail Kleymenov

    2017-01-01

    Full Text Available УДК 343Purpose of the article is to study the specific legal and informational nature of the unsolved crime in comparison with the phenomenon of delinquency, special study and analysis to improve the efficiency of law enforcement.Methods of research are abstract-logical, systematic, statistical, study of documents. The main results of research. Unsolved crime has specific legal, statistical and informational na-ture as the crime phenomenon, which is expressed in cumulative statistical population of unsolved crimes. An array of unsolved crimes is the sum of the number of acts, things of which is suspended and not terminated. The fault of the perpetrator in these cases is not proven, they are not considered by the court, it is not a conviction. Unsolved crime must be registered. Latent crime has a different informational nature. The main symptom of latent crimes is the uncertainty for the subjects of law enforcement, which delegated functions of identification, registration and accounting. Latent crime is not recorded. At the same time, there is a "border" area between the latent and unsolved crimes, which includes covered from the account of the crime. In modern Russia the majority of crimes covered from accounting by passing the decision about refusal in excitation of criminal case. Unsolved crime on their criminogenic consequences represents a significant danger to the public is higher compared to latent crime.It is conducted in the article a special analysis of the differences and similarities in the unsolved latent crime for the first time in criminological literature.The analysis proves the need for radical changes in the current Russian assessment of the state of crime and law enforcement to solve crimes. The article argues that an unsolved crime is a separate and, in contrast to latent crime, poorly understood phenomenon. However unsolved latent crime and have common features and areas of interaction.

  14. 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.

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

    Science.gov (United States)

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

    2016-09-01

    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.

  16. Estimativa do coeficiente da cultura da cana-de-açúcar em função do índice de área foliar

    Directory of Open Access Journals (Sweden)

    Samuel Silva

    2013-11-01

    Full Text Available A cana-de-açúcar vem sendo alvo de pesquisas ultimamente no que diz respeito ao desenvolvimento de técnicas viáveis para a prática da irrigação. Em função disso, esse trabalho teve como objetivo estudar a relação entre índice de área foliar (IAF e o coeficiente da cultura (Kc. Para tal, foi montado um experimento com cana-de-açúcar na região de Rio Largo, Alagoas, em que se mediu o IAF em dois ciclos de cultivo e ajustou-se o Kc às condições climáticas locais, no período de fevereiro de 2008 a fevereiro de 2009. Os resultados mostraram relação significativa entre o Kc e o IAF, em que a regressão polinomial quadrática utilizada na estimativa do Kc apresentou bom ajuste com r2 de 0,9342, índice de concordância (d de 0,9827, raiz quadrada do erro médio (RMSE de 0,0492 e erro padrão de estimativa (EPE de 0,539. A correlação entre o Kc real e o estimado pelo IAF teve coeficiente angular (b de 0,9997 e r2 de 0,9665, indicando que os valores estimados estiveram dentro da ordem de grandeza para a cana-de-açúcar. Assim, o método de regressão polinomial quadrática é viável para esta finalidade e apresenta-se como ferramenta bastante prática para o manejo da irrigação.

  17. A flexible latent class approach to estimating test-score reliability

    NARCIS (Netherlands)

    van der Palm, D.W.; van der Ark, L.A.; Sijtsma, K.

    2014-01-01

    The latent class reliability coefficient (LCRC) is improved by using the divisive latent class model instead of the unrestricted latent class model. This results in the divisive latent class reliability coefficient (DLCRC), which unlike LCRC avoids making subjective decisions about the best solution

  18. On the explaining-away phenomenon in multivariate latent variable models.

    Science.gov (United States)

    van Rijn, Peter; Rijmen, Frank

    2015-02-01

    Many probabilistic models for psychological and educational measurements contain latent variables. Well-known examples are factor analysis, item response theory, and latent class model families. We discuss what is referred to as the 'explaining-away' phenomenon in the context of such latent variable models. This phenomenon can occur when multiple latent variables are related to the same observed variable, and can elicit seemingly counterintuitive conditional dependencies between latent variables given observed variables. We illustrate the implications of explaining away for a number of well-known latent variable models by using both theoretical and real data examples. © 2014 The British Psychological Society.

  19. Políticas Públicas e Planejamento Estratégico em Turismo

    Directory of Open Access Journals (Sweden)

    Adyr Apparecida Balestreri Rodrigues

    2012-12-01

    Full Text Available Normal 0 21 false false false PT-BR X-NONE X-NONE MicrosoftInternetExplorer4 A coletânea Políticas Públicas e Planejamento Estratégico em Turismo, que agora vem a público, não é apenas mais uma obra a avolumar a extensa bibliografia brasileira publicada sobre a  temática, mas é um livro de referência, um estado da arte sobre o Turismo, tanto em nível teórico, buscando repensar paradigmas para a elaboração de novas matrizes conceituais para os estudos de turismo,  quanto  em termos operacionais, perpassando temas  distintos  e  atuais, necessários para dar suporte   às políticas públicas, ao planejamento estratégico e ao ordenamento territorial do turismo no Brasil.  A obra  consta de 29 textos, alguns em co-autoria,  e está organizada em três partes: Políticas públicas e planejamento de espaços turísticos, Sustentabilidade e Instrumentos de apoio ao planejamento. Esta compartimentação, entretanto, não se limita ao que inicialmente sugerem estes títulos. Uma leitura atenta vai desvendar ao leitor um conteúdo muito mais amplo, como aparece nos subtítulos, com múltiplos olhares, de profissionais de várias áreas do conhecimento, cujas reflexões vão se encaixando num complexo puzzle, que quando montado desenha a multifacetada e preocupante realidade do turismo no Brasil. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabela normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman

  20. Extraction of latent images from printed media

    Science.gov (United States)

    Sergeyev, Vladislav; Fedoseev, Victor

    2015-12-01

    In this paper we propose an automatic technology for extraction of latent images from printed media such as documents, banknotes, financial securities, etc. This technology includes image processing by adaptively constructed Gabor filter bank for obtaining feature images, as well as subsequent stages of feature selection, grouping and multicomponent segmentation. The main advantage of the proposed technique is versatility: it allows to extract latent images made by different texture variations. Experimental results showing performance of the method over another known system for latent image extraction are given.

  1. 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.

  2. Características agronômicas do feijão caupi inoculado em função de lâminas de irrigação e de níveis de nitrogênio

    Directory of Open Access Journals (Sweden)

    Cristiano Tagliaferre

    2013-04-01

    Full Text Available Objetivou-se, com este trabalho, estudar o efeito de diferentes lâminas de irrigação e doses de nitrogênio sobre as características agronômicas do feijão caupi inoculado. O experimento foi montado em parcelas subdivididas, tendo nas parcelas os níveis de nitrogênio e, nas subparcelas, as lâminas de irrigação, no delineamento em blocos ao acaso, com duas repetições. As lâminas de irrigação corresponderam a 578 mm (L1, 512 mm (L2, 429 mm (L3, 299 mm (L4 e 240 mm (L5 e, os níveis de nitrogênio, a 0, 30, 60 e 90 kg ha-1 de N. Os níveis de nitrogênio apresentaram respostas significativas nos componentes de produção de feijão caupi. As lâminas de irrigação proporcionaram efeitos significativos na produtividade do feijão caupi, sendo a lâmina de 426,21 mm a estimada para obtenção da produtividade máxima de 2820,03 kg ha-1.

  3. Latent variable models are network models.

    Science.gov (United States)

    Molenaar, Peter C M

    2010-06-01

    Cramer et al. present an original and interesting network perspective on comorbidity and contrast this perspective with a more traditional interpretation of comorbidity in terms of latent variable theory. My commentary focuses on the relationship between the two perspectives; that is, it aims to qualify the presumed contrast between interpretations in terms of networks and latent variables.

  4. Heteroscedastic Latent Trait Models for Dichotomous Data.

    Science.gov (United States)

    Molenaar, Dylan

    2015-09-01

    Effort has been devoted to account for heteroscedasticity with respect to observed or latent moderator variables in item or test scores. For instance, in the multi-group generalized linear latent trait model, it could be tested whether the observed (polychoric) covariance matrix differs across the levels of an observed moderator variable. In the case that heteroscedasticity arises across the latent trait itself, existing models commonly distinguish between heteroscedastic residuals and a skewed trait distribution. These models have valuable applications in intelligence, personality and psychopathology research. However, existing approaches are only limited to continuous and polytomous data, while dichotomous data are common in intelligence and psychopathology research. Therefore, in present paper, a heteroscedastic latent trait model is presented for dichotomous data. The model is studied in a simulation study, and applied to data pertaining alcohol use and cognitive ability.

  5. Latent lifestyle preferences and household location decisions

    Science.gov (United States)

    Walker, Joan L.; Li, Jieping

    2007-04-01

    Lifestyle, indicating preferences towards a particular way of living, is a key driver of the decision of where to live. We employ latent class choice models to represent this behavior, where the latent classes are the lifestyles and the choice model is the choice of residential location. Thus, we simultaneously estimate lifestyle groups and how lifestyle impacts location decisions. Empirical results indicate three latent lifestyle segments: suburban dwellers, urban dwellers, and transit-riders. The suggested lifestyle segments have intriguing policy implications. Lifecycle characteristics are used to predict lifestyle preferences, although there remain significant aspects that cannot be explained by observable variables.

  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. Learning Latent Vector Spaces for Product Search

    NARCIS (Netherlands)

    Van Gysel, C.; de Rijke, M.; Kanoulas, E.

    2016-01-01

    We introduce a novel latent vector space model that jointly learns the latent representations of words, e-commerce products and a mapping between the two without the need for explicit annotations. The power of the model lies in its ability to directly model the discriminative relation between

  8. Prevenindo pneumonia nosocomial: cuidados da equipe de saúde ao paciente em ventilação mecânica invasiva

    Directory of Open Access Journals (Sweden)

    Izaura Luzia Silvério Freire

    2006-12-01

    Full Text Available Estudo exploratório e descritivo de abordagem quantitativa, realizado na Urgência e UTI, com vistas a identificar os cuidados prestados pelos profissionais e a associação entre a VM e o aparecimento de pneumonia. A população foi de 68 profissionais. Dos 38 pacientes intubados, 17 foram a óbito e 4 extubados antes de completarem 48 horas; 13 tiveram diagnóstico de PAVM, 4 com 72 horas e 9 após esse período. Feito cultura de secreção traqueal em 10 pacientes cuja etiologia mais freqüente foi a Pseudomonas aureus. Quanto aos cuidados realizados antes da VM nos ventiladores mecânicos, circuitos respiratórios e umidificadores, em 25 não foram realizadas a limpeza e desinfecção; 21 foram montados sem técnica asséptica; no momento da instalação o ventilador foi testado 26 vezes com pulmão não estéril; o condensado, presente em 87 vezes foi descartado em 70; 52 vezes os profissionais não lavaram as mãos após esse procedimento; em 11 das 17 intubações, o médico não lavou as mãos antes; nenhum utilizou EPI; das 313 aspirações, em 249 as mãos não foram lavadas antes; das 176 dietas introduzidas, em 141 vezes não houve interrupção durante a aspiração; 232 vezes o soro fisiológico estava estéril; em menos da metade, as mãos foram lavadas após; a fisioterapia respiratória foi realizada 70 vezes e desses, em 45, os profissionais não realizaram lavagem prévia das mãos; 33 não interromperam a dieta. Predominou a mudança de decúbito no horário da manhã. Concluímos que dos 17 pacientes que permaneceram no estudo, 13 tiveram diagnóstico de PAVM entre 48 e após 72 horas de uso da VM e os dados obtidos nas observações estruturadas sinalizam para o risco desses pacientes terem PAVM.

  9. Latent class models for joint analysis of disease prevalence and high-dimensional semicontinuous biomarker data.

    Science.gov (United States)

    Zhang, Bo; Chen, Zhen; Albert, Paul S

    2012-01-01

    High-dimensional biomarker data are often collected in epidemiological studies when assessing the association between biomarkers and human disease is of interest. We develop a latent class modeling approach for joint analysis of high-dimensional semicontinuous biomarker data and a binary disease outcome. To model the relationship between complex biomarker expression patterns and disease risk, we use latent risk classes to link the 2 modeling components. We characterize complex biomarker-specific differences through biomarker-specific random effects, so that different biomarkers can have different baseline (low-risk) values as well as different between-class differences. The proposed approach also accommodates data features that are common in environmental toxicology and other biomarker exposure data, including a large number of biomarkers, numerous zero values, and complex mean-variance relationship in the biomarkers levels. A Monte Carlo EM (MCEM) algorithm is proposed for parameter estimation. Both the MCEM algorithm and model selection procedures are shown to work well in simulations and applications. In applying the proposed approach to an epidemiological study that examined the relationship between environmental polychlorinated biphenyl (PCB) exposure and the risk of endometriosis, we identified a highly significant overall effect of PCB concentrations on the risk of endometriosis.

  10. Cytokine profile in patients with early latent syphilis

    Directory of Open Access Journals (Sweden)

    Zakharov S.V.

    2018-03-01

    Full Text Available The purpose of this study was to study the change in the content of the most active cytokines (interleukins 6 and 10 during the formation of the immune response in patients with latent early syphilis, as well as to study the possible relationship between the concentrations of these cytokines and the duration of the disease. In 50 patients with early latent syphilis, the concentration of interleukins 6 and 10 in serum was studied. The serum level of interleukins was studied by the enzyme immunoassay. A statistically significant increase in the concentration of interleukin 6 in the blood of patients with latent syphilis and decrease in the interleukin 10 concentration in comparison with healthy people was established. At the same time, in patients with latent syphilis with term of infection for more than 1 year, interleukin 10 has been expressed, as compared with healthy people and, especially, with patients with syphilis with a duration of infection of up to 1 year. Along with this, a lower degree of increase in the concentration of interleukin 6 in patients with latent syphilis with a duration of infection over 1 year has been established, as compared with patients with latent syphilis with a term of infection up to 1 year, against the background of its increased concentration as compared with a group of healthy individuals.

  11. [sup 31]P-magnetic resonance spectroscopy: Impaired energy metabolism in latent hyperthyroidism. [sup 31]Phosphor-Kernspinspektroskopie: Gestoerter Energiestoffwechsel bei latenter Hyperthyreose

    Energy Technology Data Exchange (ETDEWEB)

    Theissen, P. (Klinik und Poliklinik fuer Nuklearmedizin, Univ. Koeln (Germany)); Kaldewey, S. (Klinik und Poliklinik fuer Nuklearmedizin, Univ. Koeln (Germany)); Moka, D. (Klinik und Poliklinik fuer Nuklearmedizin, Univ. Koeln (Germany)); Bunke, J. (Philips Medizin Systeme, Hamburg (Germany)); Voth, E. (Klinik und Poliklinik fuer Nuklearmedizin, Univ. Koeln (Germany)); Schicha, H. (Klinik und Poliklinik fuer Nuklearmedizin, Univ. Koeln (Germany))

    1993-06-01

    [sup 31]Phosphorous magnetic resonance spectroscopy allows an in vivo examination of energy metabolism. The present study was designed to evaluate whether in patients with latent hyperthyroidism alterations of muscle energy metabolism could be found similar to those observed in patients with overt hyperthyroidism. In 10 patients with overt hyperthyroidism before therapy and 20 with latent hyperthyroidism (also without therapy) and in 24 healthy volunteers magnetic resonance spectroscopy of the calf muscle was performed within a 1.5-Tesla magnet. Muscle concentrations of phosphocreatine, inorganic phosphate, and ATP were quantified compared to an external standard solution of K[sub 2]HPO[sub 4]. In the patients with overt hyperthyroidism and with latent hyperthyroidism a significant decrease of phosphocreatine was found. Further, the ATP concentration in patients with latent and manifest hyperthyroidism tended towards lower values. There were no significant differences in the decrease of phosphocreatine and ATP between both patient groups. Therefore, this study for the first time shows that alterations of energy metabolism in latent hyperthyroidism can be measured and that they are similar to those observed in overt hyperthyroidism. (orig.)

  12. A developmental study of latent absolute pitch memory.

    Science.gov (United States)

    Jakubowski, Kelly; Müllensiefen, Daniel; Stewart, Lauren

    2017-03-01

    The ability to recall the absolute pitch level of familiar music (latent absolute pitch memory) is widespread in adults, in contrast to the rare ability to label single pitches without a reference tone (overt absolute pitch memory). The present research investigated the developmental profile of latent absolute pitch (AP) memory and explored individual differences related to this ability. In two experiments, 288 children from 4 to12 years of age performed significantly above chance at recognizing the absolute pitch level of familiar melodies. No age-related improvement or decline, nor effects of musical training, gender, or familiarity with the stimuli were found in regard to latent AP task performance. These findings suggest that latent AP memory is a stable ability that is developed from as early as age 4 and persists into adulthood.

  13. Classification criteria of syndromes by latent variable models

    DEFF Research Database (Denmark)

    Petersen, Janne

    2010-01-01

    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......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...... standard exists for diagnosing HALS the normally applied diagnostic models cannot be used. Latent class models, which have never before been used to diagnose HALS, make it possible, under certain assumptions, to: statistically evaluate the number of phenotypes, test for mixing of HALS with other processes...

  14. Latent Transition Analysis with a Mixture Item Response Theory Measurement Model

    Science.gov (United States)

    Cho, Sun-Joo; Cohen, Allan S.; Kim, Seock-Ho; Bottge, Brian

    2010-01-01

    A latent transition analysis (LTA) model was described with a mixture Rasch model (MRM) as the measurement model. Unlike the LTA, which was developed with a latent class measurement model, the LTA-MRM permits within-class variability on the latent variable, making it more useful for measuring treatment effects within latent classes. A simulation…

  15. A Probability Distribution over Latent Causes, in the Orbitofrontal Cortex.

    Science.gov (United States)

    Chan, Stephanie C Y; Niv, Yael; Norman, Kenneth A

    2016-07-27

    The orbitofrontal cortex (OFC) has been implicated in both the representation of "state," in studies of reinforcement learning and decision making, and also in the representation of "schemas," in studies of episodic memory. Both of these cognitive constructs require a similar inference about the underlying situation or "latent cause" that generates our observations at any given time. The statistically optimal solution to this inference problem is to use Bayes' rule to compute a posterior probability distribution over latent causes. To test whether such a posterior probability distribution is represented in the OFC, we tasked human participants with inferring a probability distribution over four possible latent causes, based on their observations. Using fMRI pattern similarity analyses, we found that BOLD activity in the OFC is best explained as representing the (log-transformed) posterior distribution over latent causes. Furthermore, this pattern explained OFC activity better than other task-relevant alternatives, such as the most probable latent cause, the most recent observation, or the uncertainty over latent causes. Our world is governed by hidden (latent) causes that we cannot observe, but which generate the observations we see. A range of high-level cognitive processes require inference of a probability distribution (or "belief distribution") over the possible latent causes that might be generating our current observations. This is true for reinforcement learning and decision making (where the latent cause comprises the true "state" of the task), and for episodic memory (where memories are believed to be organized by the inferred situation or "schema"). Using fMRI, we show that this belief distribution over latent causes is encoded in patterns of brain activity in the orbitofrontal cortex, an area that has been separately implicated in the representations of both states and schemas. Copyright © 2016 the authors 0270-6474/16/367817-12$15.00/0.

  16. 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......Latent structure in complex networks, e.g., in the form of community structure, can help understand network dynamics, identify heterogeneities in network properties, and predict ‘missing’ links. While most community detection algorithms are based on optimizing heuristic clustering objectives...... as in the previous Bayesian approaches and in addition allows learning of node specific link properties similar to that in the modularity objective. We employ a new relaxation method for efficient inference in these generative models that allows us to learn the behavior of very large networks. We compare the link...

  17. A joint latent class model for classifying severely hemorrhaging trauma patients.

    Science.gov (United States)

    Rahbar, Mohammad H; Ning, Jing; Choi, Sangbum; Piao, Jin; Hong, Chuan; Huang, Hanwen; Del Junco, Deborah J; Fox, Erin E; Rahbar, Elaheh; Holcomb, John B

    2015-10-24

    In trauma research, "massive transfusion" (MT), historically defined as receiving ≥10 units of red blood cells (RBCs) within 24 h of admission, has been routinely used as a "gold standard" for quantifying bleeding severity. Due to early in-hospital mortality, however, MT is subject to survivor bias and thus a poorly defined criterion to classify bleeding trauma patients. Using the data from a retrospective trauma transfusion study, we applied a latent-class (LC) mixture model to identify severely hemorrhaging (SH) patients. Based on the joint distribution of cumulative units of RBCs and binary survival outcome at 24 h of admission, we applied an expectation-maximization (EM) algorithm to obtain model parameters. Estimated posterior probabilities were used for patients' classification and compared with the MT rule. To evaluate predictive performance of the LC-based classification, we examined the role of six clinical variables as predictors using two separate logistic regression models. Out of 471 trauma patients, 211 (45 %) were MT, while our latent SH classifier identified only 127 (27 %) of patients as SH. The agreement between the two classification methods was 73 %. A non-ignorable portion of patients (17 out of 68, 25 %) who died within 24 h were not classified as MT but the SH group included 62 patients (91 %) who died during the same period. Our comparison of the predictive models based on MT and SH revealed significant differences between the coefficients of potential predictors of patients who may be in need of activation of the massive transfusion protocol. The traditional MT classification does not adequately reflect transfusion practices and outcomes during the trauma reception and initial resuscitation phase. Although we have demonstrated that joint latent class modeling could be used to correct for potential bias caused by misclassification of severely bleeding patients, improvement in this approach could be made in the presence of time to event

  18. Morphometry of latent palmprints as a function of time.

    Science.gov (United States)

    Barros, Rodrigo M; Faria, Bruna E F; Kuckelhaus, Selma A S

    2013-12-01

    In many crimes, the elapsed time between production and collecting fingermark traces is crucial. and a method able to detect the aging of latent prints would represent an improvement in forensic procedures. Considering that as the latent print gets older, substantial changes in the relative proportion of individual components secreted by skin glands could affect the morphology of ridges, morphometry could be a potential tool to assess the aging of latent fingermarks. Then, considering the very limited research in the field, the present work aims to evaluate the morphometry of latent palmprint ridges, as a function of time, in order to identify an aging pattern. The latent marks were deposited by 20 donors on glass microscope slides considering pressure and contact angle, and then were maintained under controlled environmental conditions. The morphometric study was conducted on marks developed with magnetic powder in 7 different time intervals after deposition (0, 5, 10, 15, 20, 25 or 30 days); 60 ridges were evaluated for each developed mark. The results showed that: 1) the method for the replacement and mixing of skin secretions on the palm was appropriate to ensure reproducibility of latent prints, and 2) considering the studied group, there was a time-dependent reduction in the width of ridges and on the percentage of visible ridges over 30 days. Results suggest the possibility of using the morphometric method to determine an aging profile of latent palmprints on glass surface, aiming for forensic purposes. © 2013.

  19. 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,

  20. Immunohistochemical detection of the latent nuclear antigen-1 of the human herpesvirus type 8 to differentiate cutaneous epidemic Kaposi sarcoma and its histological simulators Detecção imuno-histoquímica do antígeno nuclear latente-1 do herpesvirus tipo 8 para diferenciar o sarcoma de Kaposi epidêmico cutâneo de seus simuladores histológicos

    Directory of Open Access Journals (Sweden)

    Patricia Fonseca Pereira

    2013-04-01

    Full Text Available Kaposi's sarcoma is the most common neoplasia diagnosed in AIDS patients and the expression of the human herpesvirus-8 (HHV-8 latent nuclear antigen-1 has been useful for its histological diagnosis. The aim of this study is to confirm that immunohistochemistry is a valuable tool for differentiating KS from its simulators in skin biopsies of HIV patients. Immunohistochemical and histological analyses were performed in 49 Kaposi's sarcoma skin biopsies and 60 of its histological simulators. Positivity was present in the 49 Kaposi's sarcoma skin biopsies and no staining was observed in the 60 simulators analyzed, resulting in sensibility and specificity of 100%. HHV-8 immunohistochemical detection is an effective tool for diagnosing Kaposi's sarcoma, especially in early lesions in which neoplastic features are not evident. It also contributes to its histological differential diagnosis.O sarcoma de Kaposi é a neoplasia mais diagnosticada em pacientes com SIDA e a expressão do antígeno nuclear latente-1 do herpesvírus humano tipo-8 (HHV-8 tem se mostrado útil no seu diagnóstico histológico. O objetivo deste estudo é confirmar que o método imuno-histoquímico é uma ferramenta útil para diferenciar o sarcoma de Kaposi cutâneo de seus simuladores histológicos em pacientes HIV positivos. Análise histológica e imuno-histoquímica foram realizadas em 49 casos de sarcoma de Kaposi cutâneo e 60 casos de seus simuladores histológicos. Positividade à imuno-histoquímica para o antígeno nuclear latente 1 do HHV-8 foi observada nos 49 casos de sarcoma de Kaposi e nenhuma reação foi detectada nos 60 simuladores analisados, resultando em 100% de sensibilidade e especificidade. A detecção do HHV-8 por imuno-histoquímica é uma ferramenta útil para o diagnóstico de sarcoma de Kaposi, especialmente na lesão inicial cujo caráter neoplásico não é evidente, e contribui para seu diagnóstico diferencial histológico.

  1. Latent fingerprints on different type of screen protective films

    Directory of Open Access Journals (Sweden)

    Yuttana Sudjaroen

    2016-07-01

    Full Text Available The purpose of this research was to study the quality of latent fingerprint on different types of screen protective films including screen protector, matte screen protector, anti-fingerprint clear screen protector and anti-fingerprint matte screen protector by using black powder method in developing latent fingerprints. The fingerprints were performed by 10 volunteers whose fingers (right index, right thumb, left index and left thumb were stubbing at different types of screen protective films and subsequently latent fingerprints were developed by brushing with black powder. Automated Fingerprint Identification System (AFIS counted the numbers of minutiae points from 320 latent fingerprints. Anti-fingerprint matte screen protective film produced the best quality of latent fingerprint with an average minutiae point 72.65, followed by matte screen protective film, clear screen protective film and anti-fingerprint clear screen protective film with an average minutiae point of 155.2, 135.0 and 72.65 respectively. The quality of latent fingerprints developed between a clear and a matte surface of screen protective films showed a significant difference (sig>0.05, whereas the coat and the non-coat with anti-fingerprint chemical revealed a non-significant difference (sig<0.05 in their number of minutiae points.

  2. Interexaminer variation of minutia markup on latent fingerprints.

    Science.gov (United States)

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

    2016-07-01

    Latent print examiners often differ in the number of minutiae they mark during analysis of a latent, and also during comparison of a latent with an exemplar. Differences in minutia counts understate interexaminer variability: examiners' markups may have similar minutia counts but differ greatly in which specific minutiae were marked. We assessed variability in minutia markup among 170 volunteer latent print examiners. Each provided detailed markup documenting their examinations of 22 latent-exemplar pairs of prints randomly assigned from a pool of 320 pairs. An average of 12 examiners marked each latent. The primary factors associated with minutia reproducibility were clarity, which regions of the prints examiners chose to mark, and agreement on value or comparison determinations. In clear areas (where the examiner was "certain of the location, presence, and absence of all minutiae"), median reproducibility was 82%; in unclear areas, median reproducibility was 46%. Differing interpretations regarding which regions should be marked (e.g., when there is ambiguity in the continuity of a print) contributed to variability in minutia markup: especially in unclear areas, marked minutiae were often far from the nearest minutia marked by a majority of examiners. Low reproducibility was also associated with differences in value or comparison determinations. Lack of standardization in minutia markup and unfamiliarity with test procedures presumably contribute to the variability we observed. We have identified factors accounting for interexaminer variability; implementing standards for detailed markup as part of documentation and focusing future training efforts on these factors may help to facilitate transparency and reduce subjectivity in the examination process. Published by Elsevier Ireland Ltd.

  3. 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...... and bound algorithm. A hybrid model consists of measurement equations, which relate latent variables to measurement indicators and utilities to choice indicators, and structural equations, which link travelers’ observable characteristics to latent variables and explanatory variables to utilities. Estimation...

  4. A quantitative analysis on latent heat of an aqueous binary mixture.

    Science.gov (United States)

    Han, Bumsoo; Choi, Jeung Hwan; Dantzig, Jonathan A; Bischof, John C

    2006-02-01

    The latent heat during phase change of water-NaCl binary mixture was measured using a differential scanning calorimeter, and the magnitude for two distinct phase change events, water/ice and eutectic phase change, were analyzed considering the phase change characteristics of a binary mixture. During the analysis, the latent heat associated with each event was calculated by normalizing the amount of each endothermic peak with only the amount of sample participating in each event estimated from the lever rule for the phase diagram. The resulting latent heat of each phase change measured is 303.7 +/- 2.5 J/g for water/ice phase change, and 233.0 +/- 1.6 J/g for eutectic phase change, respectively regardless of the initial concentration of mixture. Although the latent heats of water/ice phase change in water-NaCl mixtures are closely correlated, further study is warranted to investigate the reason for smaller latent heat of water/ice phase change than that in pure water (335 J/g). The analysis using the lever rule was extended to estimate the latent heat of dihydrate as 115 J/g with the measured eutectic and water/ice latent heat values. This new analysis based on the lever rule will be useful to estimate the latent heat of water-NaCl mixtures at various concentrations, and may become a framework for more general analysis of latent heat of various biological solutions.

  5. poLCA: An R Package for Polytomous Variable Latent Class Analysis

    Directory of Open Access Journals (Sweden)

    Drew A. Linzer

    2011-08-01

    Full Text Available poLCA is a software package for the estimation of latent class and latent class regression models for polytomous outcome variables, implemented in the R statistical computing environment. Both models can be called using a single simple command line. The basic latent class model is a finite mixture model in which the component distributions are assumed to be multi-way cross-classification tables with all variables mutually independent. The latent class regression model further enables the researcher to estimate the effects of covariates on predicting latent class membership. poLCA uses expectation-maximization and Newton-Raphson algorithms to find maximum likelihood estimates of the model parameters.

  6. Prevalence and risk factors of latent Tuberculosis among ...

    African Journals Online (AJOL)

    Background: Latent Tuberculosis treatment is a key tuberculosis control intervention. Adolescents are a high risk group that is not routinely treated in low income countries. Knowledge of latent Tuberculosis (TB) burden among adolescents may influence policy. Objectives: We determined the prevalence and risk factors of ...

  7. Assessing Trust and Effectiveness in Virtual Teams: Latent Growth Curve and Latent Change Score Models

    Directory of Open Access Journals (Sweden)

    Michael D. Coovert

    2017-08-01

    Full Text Available Trust plays a central role in the effectiveness of work groups and teams. This is the case for both face-to-face and virtual teams. Yet little is known about the development of trust in virtual teams. We examined cognitive and affective trust and their relationship to team effectiveness as reflected through satisfaction with one’s team and task performance. Latent growth curve analysis reveals both trust types start at a significant level with individual differences in that initial level. Cognitive trust follows a linear growth pattern while affective trust is overall non-linear, but becomes linear once established. Latent change score models are utilized to examine change in trust and also its relationship with satisfaction with the team and team performance. In examining only change in trust and its relationship to satisfaction there appears to be a straightforward influence of trust on satisfaction and satisfaction on trust. However, when incorporated into a bivariate coupling latent change model the dynamics of the relationship are revealed. A similar pattern holds for trust and task performance; however, in the bivariate coupling change model a more parsimonious representation is preferred.

  8. Latent semantic analysis.

    Science.gov (United States)

    Evangelopoulos, Nicholas E

    2013-11-01

    This article reviews latent semantic analysis (LSA), a theory of meaning as well as a method for extracting that meaning from passages of text, based on statistical computations over a collection of documents. LSA as a theory of meaning defines a latent semantic space where documents and individual words are represented as vectors. LSA as a computational technique uses linear algebra to extract dimensions that represent that space. This representation enables the computation of similarity among terms and documents, categorization of terms and documents, and summarization of large collections of documents using automated procedures that mimic the way humans perform similar cognitive tasks. We present some technical details, various illustrative examples, and discuss a number of applications from linguistics, psychology, cognitive science, education, information science, and analysis of textual data in general. WIREs Cogn Sci 2013, 4:683-692. doi: 10.1002/wcs.1254 CONFLICT OF INTEREST: The author has declared no conflicts of interest for this article. For further resources related to this article, please visit the WIREs website. © 2013 John Wiley & Sons, Ltd.

  9. A coarse to fine minutiae-based latent palmprint matching.

    Science.gov (United States)

    Liu, Eryun; Jain, Anil K; Tian, Jie

    2013-10-01

    With the availability of live-scan palmprint technology, high resolution palmprint recognition has started to receive significant attention in forensics and law enforcement. In forensic applications, latent palmprints provide critical evidence as it is estimated that about 30 percent of the latents recovered at crime scenes are those of palms. Most of the available high-resolution palmprint matching algorithms essentially follow the minutiae-based fingerprint matching strategy. Considering the large number of minutiae (about 1,000 minutiae in a full palmprint compared to about 100 minutiae in a rolled fingerprint) and large area of foreground region in full palmprints, novel strategies need to be developed for efficient and robust latent palmprint matching. In this paper, a coarse to fine matching strategy based on minutiae clustering and minutiae match propagation is designed specifically for palmprint matching. To deal with the large number of minutiae, a local feature-based minutiae clustering algorithm is designed to cluster minutiae into several groups such that minutiae belonging to the same group have similar local characteristics. The coarse matching is then performed within each cluster to establish initial minutiae correspondences between two palmprints. Starting with each initial correspondence, a minutiae match propagation algorithm searches for mated minutiae in the full palmprint. The proposed palmprint matching algorithm has been evaluated on a latent-to-full palmprint database consisting of 446 latents and 12,489 background full prints. The matching results show a rank-1 identification accuracy of 79.4 percent, which is significantly higher than the 60.8 percent identification accuracy of a state-of-the-art latent palmprint matching algorithm on the same latent database. The average computation time of our algorithm for a single latent-to-full match is about 141 ms for genuine match and 50 ms for impostor match, on a Windows XP desktop system with 2

  10. Association between latent toxoplasmosis and cognition in adults: a cross-sectional study.

    Science.gov (United States)

    Gale, S D; Brown, B L; Erickson, L D; Berrett, A; Hedges, D W

    2015-04-01

    Latent infection from Toxoplasma gondii (T. gondii) is widespread worldwide and has been associated with cognitive deficits in some but not all animal models and in humans. We tested the hypothesis that latent toxoplasmosis is associated with decreased cognitive function in a large cross-sectional dataset, the National Health and Nutrition Examination Survey (NHANES). There were 4178 participants aged 20-59 years, of whom 19.1% had IgG antibodies against T. gondii. Two ordinary least squares (OLS) regression models adjusted for the NHANES complex sampling design and weighted to represent the US population were estimated for simple reaction time, processing speed and short-term memory or attention. The first model included only main effects of latent toxoplasmosis and demographic control variables, and the second added interaction terms between latent toxoplasmosis and the poverty-to-income ratio (PIR), educational attainment and race-ethnicity. We also used multivariate models to assess all three cognitive outcomes in the same model. Although the models evaluating main effects only demonstrated no association between latent toxoplasmosis and the cognitive outcomes, significant interactions between latent toxoplasmosis and the PIR, between latent toxoplasmosis and educational attainment, and between latent toxoplasmosis and race-ethnicity indicated that latent toxoplasmosis may adversely affect cognitive function in certain groups.

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

    KAUST Repository

    Irincheeva, Irina; Cantoni, Eva; Genton, Marc G.

    2012-01-01

    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.

  12. 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.

  13. 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.

  14. Exposing Latent Information in Folksonomies for Reasoning

    Science.gov (United States)

    2010-01-14

    1.73 $.") http://www.w3.org/2006/07/SWD/ SKOS /reference/20081001/ Spiteri, L.F. (2007) "The structure and form of folksonomy tags: The road to the...Exposing Latent Information in Folksonomies for Reasoning January 14, 2010 Sponsored by Defense Advanced Research Projects Agency (DOD...DATES COVERED (From - To! 4/14/2009-12/23/2009 4. TITLE AND SUBTITLE Exposing Latent Information in Folksonomies for Reasoning Sa. CONTRACT

  15. 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

  16. 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...... by the notion of community structure such that the edge density within groups is higher than between groups. Our model further assumes that entities can have different propensities of generating links in one of the modes. The proposed framework is contrasted on both synthetic and real bi-partite networks...... feature representations in bipartite networks provides a new framework for accounting for structure in bi-partite networks using binary latent feature representations providing interpretable representations that well characterize structure as quantified by link prediction....

  17. Latent Growth and Dynamic Structural Equation Models.

    Science.gov (United States)

    Grimm, Kevin J; Ram, Nilam

    2018-05-07

    Latent growth models make up a class of methods to study within-person change-how it progresses, how it differs across individuals, what are its determinants, and what are its consequences. Latent growth methods have been applied in many domains to examine average and differential responses to interventions and treatments. In this review, we introduce the growth modeling approach to studying change by presenting different models of change and interpretations of their model parameters. We then apply these methods to examining sex differences in the development of binge drinking behavior through adolescence and into adulthood. Advances in growth modeling methods are then discussed and include inherently nonlinear growth models, derivative specification of growth models, and latent change score models to study stochastic change processes. We conclude with relevant design issues of longitudinal studies and considerations for the analysis of longitudinal data.

  18. 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.

  19. Aspects of physicochemical methods for the detection of latent fingerprints

    International Nuclear Information System (INIS)

    Knowles, A.M.

    1978-01-01

    This paper reviews physicochemical methods of detecting latent finger-prints on a wide range of materials commonly found at the scene of a crime, with particular emphasis placed on the newer autoradiographic techniques. This is set against a description of studies on the fundamental nature of the latent fingerprint and its host substrate, with a brief review of the history of reagents used in latent fingerprint examination. (author)

  20. Latent M. tuberculosis infection--pathogenesis, diagnosis, treatment and prevention strategies.

    Science.gov (United States)

    Druszczyńska, Magdalena; Kowalewicz-Kulbat, Magdalena; Fol, Marek; Włodarczyk, Marcin; Rudnicka, Wiesława

    2012-01-01

    One third of the earths population is infected with Mycobacterium tuberculosis (Mtb), but only 5-10% of the infected individuals develop active tuberculosis (TB) over their lifetime. The remaining 90-95% stay healthy and are called latently infected individuals. They are the biggest reservoir of the tubercle bacilli and identifying the cases of latent TB is a part of the global plan of TB control. From the clinical point of view detection of latent TB infections (LTBI) in individuals with the highest active TB risk including cases of HIV infection, autoimmune inflammatory diseases or cancer, is a priority. This review summarizes the recent findings in the pathogenesis of latent TB, its diagnosis, treatment and prevention.

  1. Alterações físico-químicas e movimentação de íons em Latossolo gibbsítico sob doses de gesso

    Directory of Open Access Journals (Sweden)

    Milson Evaldo Serafim

    2012-01-01

    Full Text Available Com o objetivo de avaliar o efeito de doses de gesso no ponto de carga zero estimado (PCZ, na dinâmica do cálcio, magnésio, potássio e sulfato, e na retenção de água de um Latossolo Vermelho distroférrico gibbsítico, textura muito argilosa, realizou-se experimento em vasos, em casa de vegetação. Foram estudadas seis doses de gesso agrícola (correspondentes a 0, 3, 6, 9, 12 e 15 Mg ha-1 e duas condições de fornecimento de água, "sem veranico" e "com veranico" para a soja cultivada. Na coleta de solo para o experimento foram consideradas as camadas 0-0,2 m e 0,7-0,9 m representando os horizontes A e Bw respectivamente. Foram montados vasos com a sobreposição de dois tubos de PVC de 0,2 m de comprimento e 0,1 m de diâmetro interno, formando duas camadas: a superior, com material do horizonte A, corrigido com calcário dolomítico, e a inferior, com material do horizonte Bw, sem correção do pH; ambas na densidade de 1 kg dm-3. O PCZ foi alterado em função das doses de gesso. Houve aumento dos teores de Ca, também em resposta as doses de gesso. Não houve diferença nos teores de S na camada superficial, mas houve aumento na camada subsuperficial em resposta à dose de gesso. Constatou-se redução nos teores de Mg na camada superficial e elevação na camada subsuperficial, com o aumento das doses de gesso. Não houve variação nos teores de K e na retenção de água para as diferentes doses de gesso e regime de fornecimento de água.

  2. Propaganda ditatorial e invasão do cotidiano: a ditadura militar em perspectiva comparada = Dictatorial propaganda and the invasion of everyday life: the military regime in Brazil in comparative perspective = Propaganda dictatorial e invasión del cotidiano: la dictadura militar brasileña en perspectiva comparada

    Directory of Open Access Journals (Sweden)

    Schneider, Nina

    2017-01-01

    Full Text Available As ditaduras do século XX usaram máquinas de propaganda distintas para justificar o seu poder ilegal. Durante o nazismo e o stalinismo, por exemplo, foram montados grandes sistemas de propaganda, envolvidos tanto na produção quanto na censura de conteúdo, que, em conjunto com outras medidas políticas (repressão violenta, vigilância, organizações de participação obrigatória, etc. , visaram a mobilizar as massas em favor do regime e silenciar qualquer tipo de oposição política. Durante o Estado Novo (1937-45, também foi montado um aparato amplo no Brasil, que tentou reforçar a sensação da união entre o suposto líder, Getúlio Vargas, e o povo (mais especificamente o trabalhador urbano – o chamado Departamento de Imprensa e Propaganda (DIP. Tomando como foco de análise a ditadura militar brasileira (1964-1985 e oferecendo uma primeira aproximação, esta contribuição investiga como a propaganda oficial – ou o órgão responsável pelas campanhas oficiais – influenciou a vida cotidiana dos cidadãos brasileiros e até que ponto o regime tentou invadir a vida privada. Revisando a pesquisa atual, este artigo pergunta: quem foi influenciado e por quais meios? O que sabemos sobre o efeito das campanhas? É possível perceber que, muito diferentemente da ditadura nazista e varguista, o regime militar operou um órgão de propaganda oficial pequeno, que rejeitou uma estratégia de politizar e mobilizar o cidadão brasileiro, bem como de invadir a sua vida cotidiana de maneira tão agressiva. Pelo contrário: apoiou-se a iniciativa privada e o livre-mercado como pilares fundamentais do sistema capitalista. Com a contratação de produtores do mercado cinematográfico, campanhas oficiais com um caráter desmobilizador e aparentemente apolítico foram elaboradas

  3. Controle de Meloidogyne javanica em mudas de bananeira 'prata-anã' por compostos orgânicos

    Directory of Open Access Journals (Sweden)

    Bruna Hanielle Carneiro dos Santos

    2013-06-01

    Full Text Available O trabalho teve como objetivo avaliar o efeito de compostos orgânicos no controle de Meloidogyne javanica, e no desenvolvimento de mudas de bananeiras 'Prata-Anã. O experimento foi conduzido em DIC, com dez repetições, e os tratamentos consistiram em quatro compostos constituídos de diferentes matérias-primas (restos da cultura da banana, cana-de-açúcar, esterco bovino, cascas de banana, plantas daninhas, capim andropogon, o esterco bovino, a torta de mamona e testemunhas (adubação mineral, carbofuran e testemunha absoluta (sem adição de composto orgânico. Em cada vaso, foram colocados 3 kg de solo autoclavado, incorporado com cada um dos tratamentos avaliados e inoculado com suspensão contendo 4.000 ovos de M. javanica. Após quatro dias, transplantou-se uma muda de bananeira 'Prata-Anã' micropropagada, e aos 60 dias, avaliaram-se: altura das plantas, diâmetro, número de folhas e peso de matéria seca da parte aérea, e número de galhas, massas de ovos, número de ovos e o número de juvenis de segundo estádio (J2, por 100 cm³ de solo. Testou-se in vitro o efeito das frações húmicas dos quatro compostos (que não causaram fitotoxidez e esterco bovino sobre a mortalidade e motilidade de J2 de M. javanica. O ensaio foi montado em placas de ELISA em DIC, com cinco repetições. Os compostos orgânicos e o esterco bovino aumentaram o desenvolvimento das mudas. A torta de mamona provocou efeito fitotóxico às mudas. Menor número de variáveis nematológicas foi proporcionado pela torta de mamona e pelo carbofuran. O número de J2 também foi menor nas parcelas tratadas com carbofuran e também pelo Composto 3, constituído por plantas daninhas+restos de cana-de-açúcar+ esterco bovino e pelo adubo mineral. Para o teste in vitro, as substâncias húmicas conferiram efeito nematicida e nematostático. Dentre os compostos, o C3 mostrou-se promissor por reduzir o desenvolvimento do nematoides e não apresentar efeito fitotóxico.

  4. Towards an HIV-1 cure: measuring the latent reservoir

    Science.gov (United States)

    Bruner, Katherine M.; Hosmane, Nina N.; Siliciano, Robert F.

    2015-01-01

    The latent reservoir of HIV-1 in resting memory CD4+ T cells serves as a major barrier to curing HIV-1 infection. While many PCR- and culture-based assays have been used to measure the size of the latent reservoir, correlation between results of different assays is poor and recent studies indicate that no available assay provides an accurate measurement of reservoir size. The discrepancies between assays are a hurdle to clinical trials that aim to measure the efficacy of HIV-1 eradication strategies. Here we describe the advantages and disadvantages of various approaches to measure the latent reservoir. PMID:25747663

  5. Ridge Width Correlations between Inked Prints and Powdered Latent Fingerprints.

    Science.gov (United States)

    De Alcaraz-Fossoul, Josep; Barrot-Feixat, Carme; Zapico, Sara C; Mancenido, Michelle; Broatch, Jennifer; Roberts, Katherine A; Carreras-Marin, Clara; Tasker, Jack

    2017-10-03

    A methodology to estimate the time of latent fingerprint deposition would be of great value to law enforcement and courts. It has been observed that ridge topography changes as latent prints age, including the widths of ridges that could be measured as a function of time. Crime suspects are commonly identified using fingerprint databases that contain reference inked tenprints (flat and rolled impressions). These can be of interest in aging studies as they provide baseline information relating to the original (nonaged) ridges' widths. In practice, the age of latent fingerprints could be estimated following a comparison process between the evidentiary aged print and the corresponding reference inked print. The present article explores possible correlations between inked and fresh latent fingerprints deposited on different substrates and visualized with TiO 2 . The results indicate that the ridge width of flat inked prints is most similar to fresh latent fingerprints , and these should be used as the comparison standard for future aging studies. © 2017 American Academy of Forensic Sciences.

  6. Study of noninvasive detection of latent fingerprints using UV laser

    Science.gov (United States)

    Li, Hong-xia; Cao, Jing; Niu, Jie-qing; Huang, Yun-gang; Mao, Lin-jie; Chen, Jing-rong

    2011-06-01

    Latent fingerprints present a considerable challenge in forensics, and noninvasive procedure that captures a digital image of the latent fingerprints is significant in the field of criminal investigation. The capability of photography technologies using 266nm UV Nd:YAG solid state laser as excitation light source to provide detailed images of unprocessed latent fingerprints is demonstrated. Unprocessed latent fingerprints were developed on various non-absorbent and absorbing substrates. According to the special absorption, reflection, scattering and fluorescence characterization of the various residues in fingerprints (fatty acid ester, protein, and carbosylic acid salts etc) to the UV light to weaken or eliminate the background disturbance and increase the brightness contrast of fingerprints with the background, and using 266nm UV laser as excitation light source, fresh and old latent fingerprints on the surface of four types of non-absorbent objects as magazine cover, glass, back of cellphone, wood desktop paintwork and two types of absorbing objects as manila envelope, notebook paper were noninvasive detected and appeared through reflection photography and fluorescence photography technologies, and the results meet the fingerprint identification requirements in forensic science.

  7. Latent tuberculosis in nursing professionals of a Brazilian hospital

    Directory of Open Access Journals (Sweden)

    Valim Andréia

    2011-05-01

    Full Text Available Abstract Tuberculosis (TB is considered an occupational disease among health-care workers (HCWs. Direct contact with TB patients leads to an increased risk to become latently infected by Mycobacterium tuberculosis. The objective of this study is to estimate the prevalence of latent M. tuberculosis minfection among nursing professionals of a hospital in Rio Grande do Sul, Brazil, assessed by tuberculin skin test (TST. From November 2009 to May 2010, latent M. tuberculosis infection was assessed by TST in 55 nursing professionals. Epidemiological information was collected using a standardized questionnaire. A positive TST result (> or = 10 mm was observed in 47.3% of the HCWs tested. There was no significant difference in TST positivity when duration of employment or professional category (technician or nurse was evaluated. The results of this work reinforce the need for control measures to prevent latent M. tuberculosis infection among nursing professionals at the hospital where the study was conducted.

  8. Diagnóstico e tratamento da tuberculose latente em pacientes com doenças inflamatórias crônicas e uso de imunobiológicos inibidores do TNF-α Diagnosis and treatment of latent tuberculosis in patients with chronic inflammatory diseases: use of TNF-alpha-targeting biological products

    Directory of Open Access Journals (Sweden)

    Diana Maria de Almeida Lopes

    2011-06-01

    Full Text Available OBJETIVO: Traçar o perfil clínico-epidemiológico de pacientes candidatos ao uso de fármacos anti-TNF-α diagnosticados como portadores de tuberculose latente (TBL e avaliar os desfechos do tratamento profilático com isoniazida. MÉTODOS: Análise descritiva prospectiva seguida de um estudo analítico observacional transversal dos desfechos do tratamento profilático em um grupo de 45 candidatos ao uso de fármacos anti-TNF-α. A avaliação dos pacientes constou de anamnese, exame clínico, radiografia de tórax e teste tuberculínico (TT por Mantoux. RESULTADOS: A idade média dos pacientes foi 45 anos, e 56,0% dos pacientes eram mulheres. Doenças reumatológicas crônicas, doenças dermatológicas crônicas e doença de Crohn estavam presentes em 46,7%, 40,0% e 13,3% dos pacientes, respectivamente. A média de enduração do TT foi 14,6 mm (variação: 5-30 mm. A maioria dos pacientes (n = 30; 66,7% apresentou enduração > 10 mm. Dos 16 pacientes com cicatriz vacinal BCG, a média de enduração foi de 15,7 mm, sendo que 14 tiveram enduração > 10 mm. Os resultados de radiografia de tórax foram considerados normais e com alterações mínimas em 64,4% e em 35,6%, respectivamente. Apenas 1 paciente (2,2% abandonou o tratamento com isoniazida, 41 (91,2% completaram o tratamento, 2 (4,4% tiveram de interromper o tratamento por hepatite medicamentosa, e 1 (2,2% foi transferido para outro hospital. Dos que completaram o tratamento, 5 apresentaram efeitos colaterais leves. CONCLUSÕES: A determinação do perfil dos candidatos ao uso de inibidores do TNF-α é importante para o manejo do tratamento da TBL, bem como para estabelecer protocolos clínicos de uso e acompanhamento do uso desses fármacosOBJECTIVE: To determine the clinical and epidemiological profile of patients who are candidates for TNF-α inhibitor use and are classified as having latent tuberculosis (LTB, as well as to evaluate the outcomes of prophylactic treatment with

  9. Primiparous women's preferences for care during a prolonged latent phase of labour.

    Science.gov (United States)

    Ängeby, Karin; Wilde-Larsson, Bodil; Hildingsson, Ingegerd; Sandin-Bojö, Ann-Kristin

    2015-10-01

    To investigate primiparous women's preferences for care during a prolonged latent phase of labour. A qualitative study based on focus groups and individual interviews and analysed with inductive content analysis. Sixteen primiparous women with a prolonged latent phase of labour >18 hours were interviewed in five focus groups (n = 11) or individually (n = 5). One main category emerged "Beyond normality - a need of individual adapted guidance in order to understand and manage an extended latent phase of labour" which covers the women's preferences during the prolonged latent phase. Five categories were generated from the data: "A welcoming manner and not being rejected", "Individually adapted care", "Important information which prepares for reality and coping", "Participation and need for feedback" and "Staying nearby the labour ward or being admitted for midwifery support". Women with a prolonged latent phase of labour sought to use their own resources, but their needs for professional support increased as time passed. A welcoming attitude from an available midwife during the latent phase created a feeling of security, and personally adapted care was perceived positively. Women with a prolonged latent phase of labour preferred woman-centred care. Midwives play an important role in supporting these women. Women's need for midwifery-support increases as the time spent in latent phase increases. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. 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

    2013-10-01

    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. Using a conventional latent variable approach, we derived an antisocial phenotype in 328 adolescents utilizing data from a 15-year follow-up of a randomized trial of a prenatal and infancy nurse-home visitation programme in Elmira, New York. We then investigated, via a novel latent variable approach, 450 informative genetic polymorphisms in 71 genes previously associated with antisocial behaviour, drug use, affiliative behaviours and stress response in 241 consenting individuals for whom DNA was available. Haplotype and Pathway analyses were also performed. Eight single-nucleotide polymorphisms (SNPs) from eight genes contributed to the latent genetic variable that in turn accounted for 16.0% of the variance within the latent antisocial phenotype. The number of risk alleles was linearly related to the latent antisocial variable scores. Haplotypes that included the putative risk alleles for all eight genes were also associated with higher latent antisocial variable scores. In addition, 33 SNPs from 63 of the remaining genes were also significant when added to the final model. Many of these genes interact on a molecular level, forming molecular networks. The results support a role for genes related to dopamine, norepinephrine, serotonin, glutamate, opioid and cholinergic signalling as well as stress response pathways in mediating susceptibility to antisocial behaviour. This preliminary study supports use of relevant behavioural indicators and latent variable approaches to study the potential 'co-action' of gene variants associated with antisocial behaviour. It also underscores the cumulative relevance of common genetic variants for understanding the aetiology of complex behaviour. If replicated in future studies, this approach may allow the identification of a

  11. Calculating latent frequencies of systems with local damping

    International Nuclear Information System (INIS)

    Kolonits, Ferenc

    2005-01-01

    Modal analysis of damped systems often cannot proceed with common real-eigenvalue techniques. The system of equilibrium equations leads to a matrix with elements being quadratic functions of a parameter λ. The values of that which make the matrix singular are the latent roots, while the solutions of the associated homogenous equation are the latent vectors. They are the (generally complex) characteristic frequencies and the mode shapes of the system, respectively. Although the theory is well developed, the numerical application is open to refinements yet. A reduction to better-known real-domain subtasks deserves attention. With a theorem of Popper and Gaspar, a n x n λ-matrix problem can be cut in two: into n-size asymmetric real matrices having as eigenvalues the n lower and n upper latent roots, ranked by absolute value. This approach may be of use for systems with high number of degrees of freedom while damped by a relatively few concentrated devices. It might fit also an earthquake analysis, where the lower portion of eigenvalues is customarily what counts. The dampers appear in the splitting algorithm as restricted-size modifications, ready for use by the Sherman-Morrison-Woodbury identity. The task is re-traced this way to a more usual real-asymmetric eigenproblem. A requirement of convergence is that the lower and upper n-set of latent values must be distinct. With odd-number degrees of freedom and neither over-damped, i.e. all latent roots being complex, this condition is surely violated. For such cases, a supplemental algorithm is proposed

  12. Behaviorism, latent learning, and cognitive maps: needed revisions in introductory psychology textbooks.

    Science.gov (United States)

    Jensen, Robert

    2006-01-01

    This paper critically assesses the scholarship in introductory psychology textbooks in relation to the topic of latent learning. A review of the treatment of latent learning in 48 introductory psychology textbooks published between 1948 and 2004, with 21 of these texts published since 1999, reveals that the scholarship on the topic of latent learning demonstrated in introductory textbooks warrants improvement. Errors that persist in textbooks include the assertion that the latent learning experiments demonstrate unequivocally that reinforcement was not necessary for learning to occur, that behavioral theories could not account for the results of the latent learning experiments, that B. F. Skinner was an S-R association behaviorist who argued that reinforcement is necessary for learning to occur, and that because behavioral theories (including that of B. F. Skinner) were unable explain the results of the latent learning experiments the cognitive map invoked by Edward Tolman is the only explanation for latent learning. Finally, the validity of the cognitive map is typically accepted without question. Implications of the presence of these errors for students and the discipline are considered. Lastly, remedies are offered to improve the scholarship found in introductory psychology textbooks.

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

    CERN Document Server

    Skrondal, Anders; Rabe-Hesketh, Sophia

    2004-01-01

    This book unifies and extends latent variable models, including multilevel or generalized linear mixed models, longitudinal or panel models, item response or factor models, latent class or finite mixture models, and structural equation models.

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

    Directory of Open Access Journals (Sweden)

    Renato Vasconcelos Botelho

    2006-04-01

    Full Text Available 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 primórdio de inflorescência; e 3 Diferenciação e formação das flores. Os primórdios indiferenciados, protuberâncias do tecido meristemático formados no interior da gema, podem dar origem a inflorescências, gavinhas ou brotações, dependendo de diversos fatores, tais como: balanço hormonal, característica varietal, vigor dos ramos, temperatura, intensidade luminosa, disponibilidade de água, nutrição mineral e práticas culturais. Do ponto de vista agronômico, concluí-se que o manejo de um vinhedo não deve visar estritamente a produção do ciclo corrente, mas também a formação das gemas para o ciclo seguinte, pois esta é a primeira condição para a obtenção de alta produtividade em videiras.

  15. Latent Class Analysis of Criminal Social Identity in a Prison Sample

    Directory of Open Access Journals (Sweden)

    Boduszek Daniel

    2014-06-01

    Full Text Available This study aimed to examine the number of latent classes of criminal social identity that exist among male recidivistic prisoners. Latent class analysis was used to identify homogeneous groups of criminal social identity. Multinomial logistic regression was used to interpret the nature of the latent classes, or groups, by estimating the associationsto number of police arrests, recidivism, and violent offending while controlling for current age. The best fitting latent class model was a five-class solution: ‘High criminal social identity’ (17%, ‘High Centrality, Moderate Affect, Low Ties’ (21.7%, ‘Low Centrality, Moderate Affect, High Ties’ (13.3%,‘Low Cognitive, High Affect, Low Ties’ (24.6%, and ‘Low criminal social identity’ (23.4%. Each of the latent classes was predicted by differing external variables. Criminal social identity is best explained by five homogenous classes that display qualitative and quantitative differences.

  16. 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

  17. Harry Potter and the sorcerer's scope: latent scope biases in explanatory reasoning.

    Science.gov (United States)

    Khemlani, Sangeet S; Sussman, Abigail B; Oppenheimer, Daniel M

    2011-04-01

    What makes a good explanation? We examine the function of latent scope, i.e., the number of unobserved phenomena that an explanation can account for. We show that individuals prefer narrow latent scope explanations-those that account for fewer unobserved effects-to broader explanations. In Experiments 1a-d, participants found narrow latent scope explanations to be both more satisfying and more likely. In Experiment 2 we directly manipulated base rate information and again found a preference for narrow latent scope explanations. Participants in Experiment 3 evaluated more natural explanations of unexpected observations, and again displayed a bias for narrow latent scope explanations. We conclude by considering what this novel bias tells us about how humans evaluate explanations and engage in causal reasoning.

  18. 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...

  19. 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…

  20. Tuberculosis and latent tuberculosis infection among healthcare workers in Kisumu, Kenya.

    Science.gov (United States)

    Agaya, Janet; Nnadi, Chimeremma D; Odhiambo, Joseph; Obonyo, Charles; Obiero, Vincent; Lipke, Virginia; Okeyo, Elisha; Cain, Kevin; Oeltmann, John E

    2015-12-01

    To assess prevalence and occupational risk factors of latent TB infection and history of TB disease ascribed to work in a healthcare setting in western Kenya. We conducted a cross-sectional survey among healthcare workers in western Kenya in 2013. They were recruited from dispensaries, health centres and hospitals that offer both TB and HIV services. School workers from the health facilities' catchment communities were randomly selected to serve as the community comparison group. Latent TB infection was diagnosed by tuberculin skin testing. HIV status of participants was assessed. Using a logistic regression model, we determined the adjusted odds of latent TB infection among healthcare workers compared to school workers; and among healthcare workers only, we assessed work-related risk factors for latent TB infection. We enrolled 1005 healthcare workers and 411 school workers. Approximately 60% of both groups were female. A total of 22% of 958 healthcare workers and 12% of 392 school workers tested HIV positive. Prevalence of self-reported history of TB disease was 7.4% among healthcare workers and 3.6% among school workers. Prevalence of latent TB infection was 60% among healthcare workers and 48% among school workers. Adjusted odds of latent TB infection were 1.5 times higher among healthcare workers than school workers (95% confidence interval 1.2-2.0). Healthcare workers at all three facility types had similar prevalence of latent TB infection (P = 0.72), but increasing years of employment was associated with increased odds of LTBI (P Kenya which offer TB and HIV services are at increased risk of latent TB infection, and the risk is similar across facility types. Implementation of WHO-recommended TB infection control measures are urgently needed in health facilities to protect healthcare workers. © 2015 John Wiley & Sons Ltd.

  1. A Multinomial Probit Model with Latent Factors

    DEFF Research Database (Denmark)

    Piatek, Rémi; Gensowski, Miriam

    2017-01-01

    be meaningfully linked to an economic model. We provide sufficient conditions that make this structure identified and interpretable. For inference, we design a Markov chain Monte Carlo sampler based on marginal data augmentation. A simulation exercise shows the good numerical performance of our sampler......We develop a parametrization of the multinomial probit model that yields greater insight into the underlying decision-making process, by decomposing the error terms of the utilities into latent factors and noise. The latent factors are identified without a measurement system, and they can...

  2. Original article Latent classes of criminal intent associated with criminal behaviour

    Directory of Open Access Journals (Sweden)

    Daniel Boduszek

    2014-07-01

    Full Text Available Background This study aimed to examine the number of latent classes of criminal intent that exist among prisoners and to look at the associations with recidivism, number of police arrests, type of offending (robbery, violent offences, murder, and multiple offences, and age. Participants and procedure Latent class analysis was used to identify homogeneous subgroups of prisoners based on their responses to the 10 questions reflecting criminal intent. Participants were 309 male recidivistic prisoners incarcerated in a maximum security prison. Multinomial logistic regression was used to interpret the nature of the latent classes, or groups, by estimating the association between recidivism and latent classes of criminal intent while controlling for offence type (robbery, violent offences, murder, and multiple offences, number of arrests, and age. Results The best fitting latent class model was a three-class solution: ‘High criminal intent’ (49.3%, ‘Intermediate criminal intent’ (41.3%, and ‘Low criminal intent’ (9.4%. The latent classes were differentially related to the external variables (recidivism, violent offences, and age. Conclusions Criminal intent is best explained by three homogeneous classes that appear to represent an underlying continuum. Future work is needed to identify whether these distinct classes of criminal intent may predict engagement in various types of criminal behaviour.

  3. Competing risk model for reduction in life expectancy from radiogenic latent cancer

    International Nuclear Information System (INIS)

    Davis, H.T.

    1978-01-01

    Because of the large number of persons who could potentially receive low doses of radiation as a result of a nuclear reactor accident, the number of fatalities from latent cancers is generally larger than the early, or prompt, fatalities. For this reason the latent cancer fatality risk of reactor accidents is perceived as being more important than the early fatality risk. In addition, there exists the temptation to add the latent cancer fatality risk to the early fatality risk for the purpose of comparing reactor accident risks to other risks that society is exposed to, such as automobile accidents, airplane accidents, hurricanes, etc. However, the impact on the individual, and society as a whole, due to latent cancer fatalities is significantly different from the impact produced by early fatalities. Early fatalities generally result in appreciable life shortening for the affected individual while latent cancer fatalities generally result in very limited life shortening. A mathematical model was developed to express the reduction in life expectancy due to latent radiogenic cancer as a function of dose received

  4. Avoiding and Correcting Bias in Score-Based Latent Variable Regression with Discrete Manifest Items

    Science.gov (United States)

    Lu, Irene R. R.; Thomas, D. Roland

    2008-01-01

    This article considers models involving a single structural equation with latent explanatory and/or latent dependent variables where discrete items are used to measure the latent variables. Our primary focus is the use of scores as proxies for the latent variables and carrying out ordinary least squares (OLS) regression on such scores to estimate…

  5. PET CT Identifies Reactivation Risk in Cynomolgus Macaques with Latent M. tuberculosis.

    Directory of Open Access Journals (Sweden)

    Philana Ling Lin

    2016-07-01

    Full Text Available Mycobacterium tuberculosis infection presents across a spectrum in humans, from latent infection to active tuberculosis. Among those with latent tuberculosis, it is now recognized that there is also a spectrum of infection and this likely contributes to the variable risk of reactivation tuberculosis. Here, functional imaging with 18F-fluorodeoxygluose positron emission tomography and computed tomography (PET CT of cynomolgus macaques with latent M. tuberculosis infection was used to characterize the features of reactivation after tumor necrosis factor (TNF neutralization and determine which imaging characteristics before TNF neutralization distinguish reactivation risk. PET CT was performed on latently infected macaques (n = 26 before and during the course of TNF neutralization and a separate set of latently infected controls (n = 25. Reactivation occurred in 50% of the latently infected animals receiving TNF neutralizing antibody defined as development of at least one new granuloma in adjacent or distant locations including extrapulmonary sites. Increased lung inflammation measured by PET and the presence of extrapulmonary involvement before TNF neutralization predicted reactivation with 92% sensitivity and specificity. To define the biologic features associated with risk of reactivation, we used these PET CT parameters to identify latently infected animals at high risk for reactivation. High risk animals had higher cumulative lung bacterial burden and higher maximum lesional bacterial burdens, and more T cells producing IL-2, IL-10 and IL-17 in lung granulomas as compared to low risk macaques. In total, these data support that risk of reactivation is associated with lung inflammation and higher bacterial burden in macaques with latent Mtb infection.

  6. Aspectos histológicos e bioquímicos de Joannesia Princips e Spathodea Campanulata, crescendo em solos na capacidade de campo, encharcado e alagado

    Directory of Open Access Journals (Sweden)

    Maria Aparecida Correa

    1985-11-01

    Full Text Available An experiment was conducted involving potted plants of Joanessia princips and Spathodea campanulata in conditions of super saturated soil, and saturated soil of normal wettness. Variations in some histological and biochenical parameters were examined. It was verified that S. campanulata has greater histological plasticity than J. princips and that only S. campanulata can withs tand super saturated conditions. The histological changes of the roots and stems of S. campanulata were notable and probably are associated with the better growth of the species in soils with low concentration of oxygen. The activity of mitogenesis in the cambial cells of the bark was greatest in S. campanulata when planted in super-satured soils. Also observed were numerosis spongy lenticels related to this increased activity. A comparison of the two species in relation to the different treatments verified in levels of alcohol in the roots. Linear regression analysis revealed significant indices between alcohol concentration and histological alterations, the highest levl of alcohol was enconrentered in J. princips.Foi montado um experimento envolvendo plantas envasadas de Joannesia princips e. Spathodea campanulata, em condições de solo alagado, encharcado e na capacidade de campo, visando detectar e estudar variações de alguns parâmetros histológicos e bioquímicos. Verificou-se que S. campanulata apresentou maior plasticidade histológica que J. princips, sendo a única a suportar a condição de solo alagado. As mudanças histológicas em raízes e caules de S. campanulata foram notáveis, podendo provavelmente serem associadas à maior sobrevivência da espécie em solos com baixos teores de oxigênio. A atividade mitogênica das células cambiais da casca foi maior em S. campanulata quando ensaiada em solo alagado. Foram ainda observadas numerosas ¡entícelas esponjosas decorrentes dessa atividade aumentada. Comparando-se as duas espécies nos diferentes

  7. 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.

  8. Latent variable modeling%建立隐性变量模型

    Institute of Scientific and Technical Information of China (English)

    蔡力

    2012-01-01

    @@ A latent variable model, as the name suggests,is a statistical model that contains latent, that is, unobserved, variables.Their roots go back to Spearman's 1904 seminal work[1] on factor analysis,which is arguably the first well-articulated latent variable model to be widely used in psychology, mental health research, and allied disciplines.Because of the association of factor analysis with early studies of human intelligence, the fact that key variables in a statistical model are, on occasion, unobserved has been a point of lingering contention and controversy.The reader is assured, however, that a latent variable,defined in the broadest manner, is no more mysterious than an error term in a normal theory linear regression model or a random effect in a mixed model.

  9. Using a latent variable model with non-constant factor loadings to examine PM2.5 constituents related to secondary inorganic aerosols.

    Science.gov (United States)

    Zhang, Zhenzhen; O'Neill, Marie S; Sánchez, Brisa N

    2016-04-01

    Factor analysis is a commonly used method of modelling correlated multivariate exposure data. Typically, the measurement model is assumed to have constant factor loadings. However, from our preliminary analyses of the Environmental Protection Agency's (EPA's) PM 2.5 fine speciation data, we have observed that the factor loadings for four constituents change considerably in stratified analyses. Since invariance of factor loadings is a prerequisite for valid comparison of the underlying latent variables, we propose a factor model that includes non-constant factor loadings that change over time and space using P-spline penalized with the generalized cross-validation (GCV) criterion. The model is implemented using the Expectation-Maximization (EM) algorithm and we select the multiple spline smoothing parameters by minimizing the GCV criterion with Newton's method during each iteration of the EM algorithm. The algorithm is applied to a one-factor model that includes four constituents. Through bootstrap confidence bands, we find that the factor loading for total nitrate changes across seasons and geographic regions.

  10. Accuracy of latent-variable estimation in Bayesian semi-supervised learning.

    Science.gov (United States)

    Yamazaki, Keisuke

    2015-09-01

    Hierarchical probabilistic models, such as Gaussian mixture models, are widely used for unsupervised learning tasks. These models consist of observable and latent variables, which represent the observable data and the underlying data-generation process, respectively. Unsupervised learning tasks, such as cluster analysis, are regarded as estimations of latent variables based on the observable ones. The estimation of latent variables in semi-supervised learning, where some labels are observed, will be more precise than that in unsupervised, and one of the concerns is to clarify the effect of the labeled data. However, there has not been sufficient theoretical analysis of the accuracy of the estimation of latent variables. In a previous study, a distribution-based error function was formulated, and its asymptotic form was calculated for unsupervised learning with generative models. It has been shown that, for the estimation of latent variables, the Bayes method is more accurate than the maximum-likelihood method. The present paper reveals the asymptotic forms of the error function in Bayesian semi-supervised learning for both discriminative and generative models. The results show that the generative model, which uses all of the given data, performs better when the model is well specified. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. 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

    Directory of Open Access Journals (Sweden)

    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

  12. 31P-magnetic resonance spectroscopy: Impaired energy metabolism in latent hyperthyroidism

    International Nuclear Information System (INIS)

    Theissen, P.; Kaldewey, S.; Moka, D.; Bunke, J.; Voth, E.; Schicha, H.

    1993-01-01

    31 Phosphorous magnetic resonance spectroscopy allows an in vivo examination of energy metabolism. The present study was designed to evaluate whether in patients with latent hyperthyroidism alterations of muscle energy metabolism could be found similar to those observed in patients with overt hyperthyroidism. In 10 patients with overt hyperthyroidism before therapy and 20 with latent hyperthyroidism (also without therapy) and in 24 healthy volunteers magnetic resonance spectroscopy of the calf muscle was performed within a 1.5-Tesla magnet. Muscle concentrations of phosphocreatine, inorganic phosphate, and ATP were quantified compared to an external standard solution of K 2 HPO 4 . In the patients with overt hyperthyroidism and with latent hyperthyroidism a significant decrease of phosphocreatine was found. Further, the ATP concentration in patients with latent and manifest hyperthyroidism tended towards lower values. There were no significant differences in the decrease of phosphocreatine and ATP between both patient groups. Therefore, this study for the first time shows that alterations of energy metabolism in latent hyperthyroidism can be measured and that they are similar to those observed in overt hyperthyroidism. (orig.) [de

  13. Latent class factor and cluster models, bi-plots and tri-plots and related graphical displays

    NARCIS (Netherlands)

    Magidson, J.; Vermunt, J.K.

    2001-01-01

    We propose an alternative method of conducting exploratory latent class analysis that utilizes latent class factor models, and compare it to the more traditional approach based on latent class cluster models. We show that when formulated in terms of R mutually independent, dichotomous latent

  14. Biossegurança em tuberculose e os profissionais de enfermagem do Hospital Universitário Clementino Fraga Filho da UFRJ

    OpenAIRE

    Souza, Soraia Riva Goudinho de

    2010-01-01

    Introdução: Quando se observam as tendências e preocupações em relação à biossegurança em tuberculose, pensa-se no profissional de enfermagem não apenas como um integrante na promoção da saúde, mas como um profissional que desenvolve suas atividades próximas aos pacientes bacilíferos. Objetivo: Conhecer os riscos da Tuberculose ou da Infecção Latente por Tuberculose entre os (as) enfermeiros (as) do Hospital Universitário Clementino Fraga Filho na cidade do Rio de Janeiro. Métodos: Estudo qua...

  15. 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.

  16. Latent class models for classification

    NARCIS (Netherlands)

    Vermunt, J.K.; Magidson, J.

    2003-01-01

    An overview is provided of recent developments in the use of latent class (LC) and other types of finite mixture models for classification purposes. Several extensions of existing models are presented. Two basic types of LC models for classification are defined: supervised and unsupervised

  17. On Latent Growth Models for Composites and Their Constituents.

    Science.gov (United States)

    Hancock, Gregory R; Mao, Xiulin; Kher, Hemant

    2013-09-01

    Over the last decade and a half, latent growth modeling has become an extremely popular and versatile technique for evaluating longitudinal change and its determinants. Most common among the models applied are those for a single measured variable over time. This model has been extended in a variety of ways, most relevant for the current work being the multidomain and the second-order latent growth models. Whereas the former allows for growth function characteristics to be modeled for multiple outcomes simultaneously, with the degree of growth characteristics' relations assessed within the model (e.g., cross-domain slope factor correlations), the latter models growth in latent outcomes, each of which has effect indicators repeated over time. But what if one has an outcome that is believed to be formative relative to its indicator variables rather than latent? In this case, where the outcome is a composite of multiple constituents, modeling change over time is less straightforward. This article provides analytical and applied details for simultaneously modeling growth in composites and their constituent elements, including a real data example using a general computer self-efficacy questionnaire.

  18. Piecewise Linear-Linear Latent Growth Mixture Models with Unknown Knots

    Science.gov (United States)

    Kohli, Nidhi; Harring, Jeffrey R.; Hancock, Gregory R.

    2013-01-01

    Latent growth curve models with piecewise functions are flexible and useful analytic models for investigating individual behaviors that exhibit distinct phases of development in observed variables. As an extension of this framework, this study considers a piecewise linear-linear latent growth mixture model (LGMM) for describing segmented change of…

  19. Rapid detection of drug metabolites in latent fingermarks.

    Science.gov (United States)

    Hazarika, Pompi; Jickells, Sue M; Russell, David A

    2009-01-01

    Magnetic particles functionalised with anti-cotinine antibody have been used to image latent fingermarks through the detection of the cotinine antigen in the sweat deposited within the fingerprints of smokers. The antibody-magnetic particle conjugates are readily applied to latent fingerprints while excess reagents are removed through the use of a magnetic wand. The results have shown that drug metabolites, such as cotinine, can be detected and used to image the fingermark to establish the identity of an individual within 15 minutes.

  20. Effects of latent toxoplasmosis on autoimmune thyroid diseases in pregnancy.

    Science.gov (United States)

    Kaňková, Šárka; Procházková, Lucie; Flegr, Jaroslav; Calda, Pavel; Springer, Drahomíra; Potluková, Eliška

    2014-01-01

    Toxoplasmosis, one of the most common zoonotic diseases worldwide, can induce various hormonal and behavioural alterations in infected hosts, and its most common form, latent toxoplasmosis, influences the course of pregnancy. Autoimmune thyroid diseases (AITD) belong to the well-defined risk factors for adverse pregnancy outcomes. The aim of this study was to investigate whether there is a link between latent toxoplasmosis and maternal AITD in pregnancy. Cross-sectional study in 1248 consecutive pregnant women in the 9-12th gestational weeks. Serum thyroid-stimulating hormone (TSH), thyroperoxidase antibodies (TPOAb), and free thyroxine (FT4) were assessed by chemiluminescence; the Toxoplasma status was detected by the complement fixation test (CFT) and anti-Toxoplasma IgG enzyme-linked immunosorbent assay (ELISA). Overall, 22.5% of the women were positive for latent toxoplasmosis and 14.7% were screened positive for AITD. Women with latent toxoplasmosis had more often highly elevated TPOAb than the Toxoplasma-negative ones (p = 0.004), and latent toxoplasmosis was associated with decrease in serum TSH levels (p = 0.049). Moreover, we found a positive correlation between FT4 and the index of positivity for anti-Toxoplasma IgG antibodies (p = 0.033), which was even stronger in the TPOAb-positive Toxoplasma-positive women, (p = 0.014), as well as a positive correlation between FT4 and log2 CFT (p = 0.009). Latent toxoplasmosis was associated with a mild increase in thyroid hormone production in pregnancy. The observed Toxoplasma-associated changes in the parameters of AITD are mild and do not seem to be clinically relevant; however, they could provide new clues to the complex pathogenesis of autoimmune thyroid diseases.

  1. Remoção de sólidos suspensos e totais em biofiltros operando com esgoto doméstico primário para reuso na agricultura

    Directory of Open Access Journals (Sweden)

    Rafael Oliveira Batista

    2013-02-01

    Full Text Available Este trabalho objetivou analisar a remoção de sólidos suspensos e totais em biofiltros, preenchidos com lixo compostado, bagaço de cana-de-açúcar e serragem de madeira, submetidos às taxas de aplicação do esgoto doméstico de 0,5, 1,0 e 1,5 m³ m-2 d-1, em Viçosa-MG. Para isso, foi montada uma bancada experimental, constituída de 27 biofiltros, em área experimental da Universidade Federal de Viçosa. As concentrações de sólidos suspensos e totais foram determinadas, mensalmente, durante período de 153 dias. O experimento foi montado no esquema de parcelas subsubdivididas, tendo, nas parcelas, as taxas de aplicação do esgoto doméstico; nas subparcelas, os tipos de material orgânico e, nas subsubparcelas, os períodos de avaliação, no delineamento em blocos casualizados, com três repetições. Os resultados indicaram que os biofiltros proporcionaram remoções de sólidos suspensos e totais de até 82 e 46%, no esgoto doméstico, após 153 dias de operação; a serragem de madeira foi o tipo de material orgânico filtrante com melhor desempenho no tratamento de esgoto doméstico; as aplicações de taxas de 0,5, 1,0 e 1,5 m³ m-2 d-1 de esgoto não apresentaram diferenças quanto à remoção de sólidos suspensos e totais; e a utilização de biofiltros minimiza a obstrução de emissores causada por sólidos suspensos, quando do aproveitamento agrícola de esgoto doméstico, por via do sistema de irrigação por gotejamento.

  2. Latent effectiveness of desiccant wheel: A silica gels- water system

    International Nuclear Information System (INIS)

    Rabah, A. A.; Mohamed, S. A.

    2009-01-01

    A latent heat effectiveness model in term of dimensionless groups? =f (NTU, m * ,Crm * ) for energy wheel has been analytically derived. The energy wheel is divided into humidification and dehumidification sections. For each section macroscopic mass differential equations for gas and the matrix were applied. In this process local latent effectiveness (? c ,? h ) for the humidification and dehumidification section of the wheel were obtained. The Latent effectiveness of the wheel is then derived form local effectiveness [? =f (? c ,? h)]. The model is compared with the existing experimental investigation and manufacturer data for energy wheel. More than 90% of the experimental data within a confidence limit of 95%. (Author)

  3. Intercept Centering and Time Coding in Latent Difference Score Models

    Science.gov (United States)

    Grimm, Kevin J.

    2012-01-01

    Latent difference score (LDS) models combine benefits derived from autoregressive and latent growth curve models allowing for time-dependent influences and systematic change. The specification and descriptions of LDS models include an initial level of ability or trait plus an accumulation of changes. A limitation of this specification is that the…

  4. Large-scale weakly supervised object localization via latent category learning.

    Science.gov (United States)

    Chong Wang; Kaiqi Huang; Weiqiang Ren; Junge Zhang; Maybank, Steve

    2015-04-01

    Localizing objects in cluttered backgrounds is challenging under large-scale weakly supervised conditions. Due to the cluttered image condition, objects usually have large ambiguity with backgrounds. Besides, there is also a lack of effective algorithm for large-scale weakly supervised localization in cluttered backgrounds. However, backgrounds contain useful latent information, e.g., the sky in the aeroplane class. If this latent information can be learned, object-background ambiguity can be largely reduced and background can be suppressed effectively. In this paper, we propose the latent category learning (LCL) in large-scale cluttered conditions. LCL is an unsupervised learning method which requires only image-level class labels. First, we use the latent semantic analysis with semantic object representation to learn the latent categories, which represent objects, object parts or backgrounds. Second, to determine which category contains the target object, we propose a category selection strategy by evaluating each category's discrimination. Finally, we propose the online LCL for use in large-scale conditions. Evaluation on the challenging PASCAL Visual Object Class (VOC) 2007 and the large-scale imagenet large-scale visual recognition challenge 2013 detection data sets shows that the method can improve the annotation precision by 10% over previous methods. More importantly, we achieve the detection precision which outperforms previous results by a large margin and can be competitive to the supervised deformable part model 5.0 baseline on both data sets.

  5. Reliability measures in item response theory: manifest versus latent correlation functions.

    Science.gov (United States)

    Milanzi, Elasma; Molenberghs, Geert; Alonso, Ariel; Verbeke, Geert; De Boeck, Paul

    2015-02-01

    For item response theory (IRT) models, which belong to the class of generalized linear or non-linear mixed models, reliability at the scale of observed scores (i.e., manifest correlation) is more difficult to calculate than latent correlation based reliability, but usually of greater scientific interest. This is not least because it cannot be calculated explicitly when the logit link is used in conjunction with normal random effects. As such, approximations such as Fisher's information coefficient, Cronbach's α, or the latent correlation are calculated, allegedly because it is easy to do so. Cronbach's α has well-known and serious drawbacks, Fisher's information is not meaningful under certain circumstances, and there is an important but often overlooked difference between latent and manifest correlations. Here, manifest correlation refers to correlation between observed scores, while latent correlation refers to correlation between scores at the latent (e.g., logit or probit) scale. Thus, using one in place of the other can lead to erroneous conclusions. Taylor series based reliability measures, which are based on manifest correlation functions, are derived and a careful comparison of reliability measures based on latent correlations, Fisher's information, and exact reliability is carried out. The latent correlations are virtually always considerably higher than their manifest counterparts, Fisher's information measure shows no coherent behaviour (it is even negative in some cases), while the newly introduced Taylor series based approximations reflect the exact reliability very closely. Comparisons among the various types of correlations, for various IRT models, are made using algebraic expressions, Monte Carlo simulations, and data analysis. Given the light computational burden and the performance of Taylor series based reliability measures, their use is recommended. © 2014 The British Psychological Society.

  6. Evaluation of <em>HER2em> Gene Amplification in Breast Cancer Using Nuclei Microarray <em>in em>S>itu em>Hybridization

    Directory of Open Access Journals (Sweden)

    Xuefeng Zhang

    2012-05-01

    Full Text Available Fluorescence<em> em>>in situ em>hybridization (FISH assay is considered the “gold standard” in evaluating <em>HER2/neu (HER2em> gene status. However, FISH detection is costly and time consuming. Thus, we established nuclei microarray with extracted intact nuclei from paraffin embedded breast cancer tissues for FISH detection. The nuclei microarray FISH (NMFISH technology serves as a useful platform for analyzing <em>HER2em> gene/chromosome 17 centromere ratio. We examined <em>HER2em> gene status in 152 cases of invasive ductal carcinomas of the breast that were resected surgically with FISH and NMFISH. <em>HER2em> gene amplification status was classified according to the guidelines of the American Society of Clinical Oncology and College of American Pathologists (ASCO/CAP. Comparison of the cut-off values for <em>HER2em>/chromosome 17 centromere copy number ratio obtained by NMFISH and FISH showed that there was almost perfect agreement between the two methods (κ coefficient 0.920. The results of the two methods were almost consistent for the evaluation of <em>HER2em> gene counts. The present study proved that NMFISH is comparable with FISH for evaluating <em>HER2em> gene status. The use of nuclei microarray technology is highly efficient, time and reagent conserving and inexpensive.

  7. Longitudinal Physical Activity Patterns Among Older Adults: A Latent Transition Analysis.

    Science.gov (United States)

    Mooney, Stephen J; Joshi, Spruha; Cerdá, Magdalena; Kennedy, Gary J; Beard, John R; Rundle, Andrew G

    2018-05-14

    Most epidemiologic studies of physical activity measure either total energy expenditure or engagement in a single activity type, such as walking. These approaches may gloss over important nuances in activity patterns. We performed a latent transition analysis to identify patterns of activity types as well as neighborhood and individual determinants of changes in those activity patterns over two years in a cohort of 2,023 older adult residents of New York City, NY, surveyed between 2011 and 2013. We identified seven latent classes: 1) Mostly Inactive, 2) Walking, 3) Exercise, 4) Household Activities and Walking, 5) Household Activities and Exercise, 6) Gardening and Household Activities, and 7) Gardening, Household Activities, and Exercise. The majority of subjects retained the same activity patterns between waves (54% unchanged between waves 1 and 2, 66% unchanged between waves 2 and 3).Most latent class transitions were between classes distinguished only by one form of activity, and only neighborhood unemployment was consistently associated with changing between activity latent classes. Future latent transition analyses of physical activity would benefit from larger cohorts and longer follow-up periods to assess predictors of and long-term impacts of changes in activity patterns.

  8. Neonatal Phosphate Nutrition Alters <em>in em>Vivo> and <em>in em>Vitro> Satellite Cell Activity in Pigs

    Directory of Open Access Journals (Sweden)

    Chad H. Stahl

    2012-05-01

    Full Text Available Satellite cell activity is necessary for postnatal skeletal muscle growth. Severe phosphate (PO4 deficiency can alter satellite cell activity, however the role of neonatal PO4 nutrition on satellite cell biology remains obscure. Twenty-one piglets (1 day of age, 1.8 ± 0.2 kg BW were pair-fed liquid diets that were either PO4 adequate (0.9% total P, supra-adequate (1.2% total P in PO4 requirement or deficient (0.7% total P in PO4 content for 12 days. Body weight was recorded daily and blood samples collected every 6 days. At day 12, pigs were orally dosed with BrdU and 12 h later, satellite cells were isolated. Satellite cells were also cultured <em>in vitroem> for 7 days to determine if PO4 nutrition alters their ability to proceed through their myogenic lineage. Dietary PO4 deficiency resulted in reduced (<em>P> < 0.05 sera PO4 and parathyroid hormone (PTH concentrations, while supra-adequate dietary PO4 improved (<em>P> < 0.05 feed conversion efficiency as compared to the PO4 adequate group. <em>In vivoem> satellite cell proliferation was reduced (<em>P> < 0.05 among the PO4 deficient pigs, and these cells had altered <em>in vitroem> expression of markers of myogenic progression. Further work to better understand early nutritional programming of satellite cells and the potential benefits of emphasizing early PO4 nutrition for future lean growth potential is warranted.

  9. 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...... 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...... and Link Nested Logit. Estimates were produced from model specifications that considered level-of-service, label and facility dummy variables. Moreover, a modelling framework was designed to represent drivers’ choices as affected by the latent constructs extracted with factor analysis. Previous experience...

  10. A Taxonomy of Latent Structure Assumptions for Probability Matrix Decomposition Models.

    Science.gov (United States)

    Meulders, Michel; De Boeck, Paul; Van Mechelen, Iven

    2003-01-01

    Proposed a taxonomy of latent structure assumptions for probability matrix decomposition (PMD) that includes the original PMD model and a three-way extension of the multiple classification latent class model. Simulation study results show the usefulness of the taxonomy. (SLD)

  11. Rapid visualization of latent fingermarks using gold seed-mediated enhancement

    Directory of Open Access Journals (Sweden)

    Chia-Hao Su

    2016-11-01

    Full Text Available Abstract Background Fingermarks are one of the most important and useful forms of physical evidence in forensic investigations. However, latent fingermarks are not directly visible, but can be visualized due to the presence of other residues (such as inorganic salts, proteins, polypeptides, enzymes and human metabolites which can be detected or recognized through various strategies. Convenient and rapid techniques are still needed to provide obvious contrast between the background and the fingermark ridges and to then visualize latent fingermark with a high degree of selectivity and sensitivity. Results In this work, lysozyme-binding aptamer-conjugated Au nanoparticles (NPs are used to recognize and target lysozyme in the fingermark ridges, and Au+-complex solution is used as a growth agent to reduce Au+ from Au+ to Au0 on the surface of the Au NPs. Distinct fingermark patterns were visualized on a range of professional forensic within 3 min; the resulting images could be observed by the naked eye without background interference. The entire processes from fingermark collection to visualization only entails two steps and can be completed in less than 10 min. The proposed method provides cost and time savings over current fingermark visualization methods. Conclusions We report a simple, inexpensive, and fast method for the rapid visualization of latent fingermarks on the non-porous substrates using Au seed-mediated enhancement. Au seed-mediated enhancement is used to achieve the rapid visualization of latent fingermarks on non-porous substrates by the naked eye without the use of expensive or sophisticated instruments. The proposed approach offers faster detection and visualization of latent fingermarks than existing methods. The proposed method is expected to increase detection efficiency for latent fingermarks and reduce time requirements and costs for forensic investigations.

  12. 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…

  13. Interferon-gamma release assay for the diagnosis of latent tuberculosis infection: A latent-class analysis.

    Directory of Open Access Journals (Sweden)

    Tan N Doan

    Full Text Available Accurate diagnosis and subsequent treatment of latent tuberculosis infection (LTBI is essential for TB elimination. However, the absence of a gold standard test for diagnosing LTBI makes assessment of the true prevalence of LTBI and the accuracy of diagnostic tests challenging. Bayesian latent class models can be used to make inferences about disease prevalence and the sensitivity and specificity of diagnostic tests using data on the concordance between tests. We performed the largest meta-analysis to date aiming to evaluate the performance of tuberculin skin test (TST and interferon-gamma release assays (IGRAs for LTBI diagnosis in various patient populations using Bayesian latent class modelling.Systematic search of PubMeb, Embase and African Index Medicus was conducted without date and language restrictions on September 11, 2017 to identify studies that compared the performance of TST and IGRAs for LTBI diagnosis. Two IGRA methods were considered: QuantiFERON-TB Gold In Tube (QFT-GIT and T-SPOT.TB. Studies were included if they reported 2x2 agreement data between TST and QFT-GIT or T-SPOT.TB. A Bayesian latent class model was developed to estimate the sensitivity and specificity of TST and IGRAs in various populations, including immune-competent adults, immune-compromised adults and children. A TST cut-off value of 10 mm was used for immune-competent subjects and 5 mm for immune-compromised individuals.A total of 157 studies were included in the analysis. In immune-competent adults, the sensitivity of TST and QFT-GIT were estimated to be 84% (95% credible interval [CrI] 82-85% and 52% (50-53%, respectively. The specificity of QFT-GIT was 97% (96-97% in non-BCG-vaccinated and 93% (92-94% in BCG-vaccinated immune-competent adults. The estimated figures for TST were 100% (99-100% and 79% (76-82%, respectively. T-SPOT.TB has comparable specificity (97% for both tests and better sensitivity (68% versus 52% than QFT-GIT in immune-competent adults

  14. Latent Toxoplasma gondii infection leads to improved action control.

    Science.gov (United States)

    Stock, Ann-Kathrin; Heintschel von Heinegg, Evelyn; Köhling, Hedda-Luise; Beste, Christian

    2014-03-01

    The parasite Toxoplasma gondii has been found to manipulate the behavior of its secondary hosts to increase its own dissemination which is commonly believed to be to the detriment of the host (manipulation hypothesis). The manipulation correlates with an up-regulation of dopaminergic neurotransmission. In humans, different pathologies have been associated with T. gondii infections but most latently infected humans do not seem to display overt impairments. Since a dopamine plus does not necessarily bear exclusively negative consequences in humans, we investigated potential positive consequences of latent toxoplasmosis (and the presumed boosting of dopaminergic neurotransmission) on human cognition and behavior. For this purpose, we focused on action cascading which has been shown to be modulated by dopamine. Based on behavioral and neurophysiological (EEG) data obtained by means of a stop-change paradigm, we were able to demonstrate that healthy young humans can actually benefit from latent T. gondii infection as regards their performance in this task (as indicated by faster response times and a smaller P3 component). The data shows that a latent infection which is assumed to affect the dopaminergic system can lead to paradoxical improvements of cognitive control processes in humans. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. 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.

  16. 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…

  17. Barreiras no tratamento da infecção latente por tuberculose (ILTB na criança: um estudo de caso

    Directory of Open Access Journals (Sweden)

    Adriana Rodrigues da Silva

    2014-09-01

    Full Text Available Objetivo: Analisar as barreiras enfrentadas pelo familiar no tratamento da infecção latente por tuberculose (ILTB na criança. Métodos: Estudo descritivo, em duas etapas. Na primeira, analisados prontuários de crianças de 0 a 11 anos tratadas para ILTB em um centro municipal de saúde no Município do Rio de Janeiro. Na segunda, entrevista com os familiares. Nas duas etapas buscou-se identificar barreiras pessoais, familiares, econômicas, sociais e do serviço. Resultados: Primeira etapa; houve barreiras (47/228: no serviço - 4 (8,5%; pessoais - 4 (8,5%; familiares - 21 (44,7%; fisiológicas - 12 (25,5%. Na segunda; houve barreiras (50/85: econômicas - 19 (38%; sociais - 13 (26%; pessoais e familiares - 18 (36%. Conclusão: Fatores socioeconômicos desfavoráveis afetaram o cuidado da criança nas duas etapas do estudo. Repensar na forma de lidar com os determinantes sociais associados à tuberculose pode ser o caminho para evitar abandono e interrupções deste tratamento.

  18. Probabilistic Latent Semantic Analyses (PLSA in Bibliometric Analysis for Technology Forecasting

    Directory of Open Access Journals (Sweden)

    Wang Zan

    2007-03-01

    Full Text Available Due to the availability of internet-based abstract services and patent databases, bibliometric analysis has become one of key technology forecasting approaches. Recently, latent semantic analysis (LSA has been applied to improve the accuracy in document clustering. In this paper, a new LSA method, probabilistic latent semantic analysis (PLSA which uses probabilistic methods and algebra to search latent space in the corpus is further applied in document clustering. The results show that PLSA is more accurate than LSA and the improved iteration method proposed by authors can simplify the computing process and improve the computing efficiency

  19. Ocorrência de Ornithonyssus bursa (Berlese, 1888 (Acari: Macronyssidae em filhotes de Megascops choliba (corujinha-do-mato e Pitangus sulphuratus (bem-te-vi, no Rio Grande do Sul, Brasil Ocurrence of Ornithonyssus bursa (Berlese, 1888 (Acari: Macronyssidae on Megascops choliba (tropical screech-owl and Pitangus sulphuratus (great kiskadee nestlings in the Rio Grande do Sul State, Brazil

    Directory of Open Access Journals (Sweden)

    Carolina S. Mascarenhas

    2009-12-01

    Full Text Available O Núcleo de Reabilitação da Fauna Silvestre e Centro de Triagem de Animais Silvestres da Universidade Federal de Pelotas - RS atendeu dois filhotes de Megascops choliba (corujinha-do-mato (Strigiformes - Strigidae e dois de Pitangus sulphuratus (bem-te-vi (Passeriformes - Tyrannidae intensamente parasitados por ácaros, em maio de 2005 e dezembro de 2006, respectivamente. Os filhotes e o ninho de P. sulphuratus foram recolhidos na zona urbana da cidade de Pelotas - RS após forte temporal. Os ácaros foram removidos, colocados em álcool 70% e levados ao laboratório de parasitologia para identificação. Os espécimes foram clarificados em lactofenol, montados em meio de Hoyer e identificados como Ornithonyssus bursa (Acari - Macronyssidae. Registra-se Megascops choliba e Pitangus sulphuratus como hospedeiros de Ornithonyssus bursa, no Rio Grande do Sul, Brasil.The Center for Rehabilitation of Wildlife and Center for Selection of Wild Animal of the Federal University of Pelotas has attended two nestlings of Megascops choliba (tropical screech-owl (Strigiformes - Strigidae and two of Pitangus sulphuratus (great kiskadee (Passeriformes - Tyrannidae heavily parasitized by mites, in May 2005 and December 2006, respectively. The nestlings and the nest of P. sulphuratus were collected in the Pelotas urban area after severe storms. The mites were removed, clarified in lactofenol, permanently mounted in Hoyer's medium and identified as Ornithonyssus bursa (Acari - Macronyssidae. Megascops choliba and Pitangus sulphuratus are reported as host of Ornithonyssus bursa in Rio Grande do Sul State, Brazil.

  20. Latent class models in financial data analysis

    Directory of Open Access Journals (Sweden)

    Attilio Gardini

    2007-10-01

    Full Text Available This paper deals with optimal international portfolio choice by developing a latent class approach based on the distinction between international and non-international investors. On the basis of micro data, we analyze the effects of many social, demographic, economic and financial characteristics on the probability to be an international investor. Traditional measures of equity home bias do not allow for the existence of international investment rationing operators. On the contrary, by resorting to latent class analysis it is possible to detect the unobservable distinction between international investors and investors who are precluded from operating into international financial markets and, therefore, to evaluate the role of these unobservable constraints on equity home bias.

  1. The Integration of Continuous and Discrete Latent Variable Models: Potential Problems and Promising Opportunities

    Science.gov (United States)

    Bauer, Daniel J.; Curran, Patrick J.

    2004-01-01

    Structural equation mixture modeling (SEMM) integrates continuous and discrete latent variable models. Drawing on prior research on the relationships between continuous and discrete latent variable models, the authors identify 3 conditions that may lead to the estimation of spurious latent classes in SEMM: misspecification of the structural model,…

  2. Characterization of a Latent Virus-Like Infection of Symbiotic Zooxanthellae▿

    Science.gov (United States)

    Lohr, Jayme; Munn, Colin B.; Wilson, William H.

    2007-01-01

    A latent virus-like agent, which we designated zooxanthella filamentous virus 1 (ZFV1), was isolated from Symbiodinium sp. strain CCMP 2465 and characterized. Transmission electron microscopy and analytical flow cytometry revealed the presence of a new group of distinctive filamentous virus-like particles after exposure of the zooxanthellae to UV light. Examination of thin sections of the zooxanthellae revealed the formation and proliferation of filamentous virus-like particles in the UV-induced cells. Assessment of Symbiodinium sp. cultures was used here as a model to show the effects of UV irradiance and induction of potential latent viruses. The unique host-virus system described here provides insight into the role of latent infections in zooxanthellae through environmentally regulated viral induction mechanisms. PMID:17351090

  3. Characterization of a latent virus-like infection of symbiotic zooxanthellae.

    Science.gov (United States)

    Lohr, Jayme; Munn, Colin B; Wilson, William H

    2007-05-01

    A latent virus-like agent, which we designated zooxanthella filamentous virus 1 (ZFV1), was isolated from Symbiodinium sp. strain CCMP 2465 and characterized. Transmission electron microscopy and analytical flow cytometry revealed the presence of a new group of distinctive filamentous virus-like particles after exposure of the zooxanthellae to UV light. Examination of thin sections of the zooxanthellae revealed the formation and proliferation of filamentous virus-like particles in the UV-induced cells. Assessment of Symbiodinium sp. cultures was used here as a model to show the effects of UV irradiance and induction of potential latent viruses. The unique host-virus system described here provides insight into the role of latent infections in zooxanthellae through environmentally regulated viral induction mechanisms.

  4. The latent effect of inertia in the modal choice

    DEFF Research Database (Denmark)

    Cherchi, Elisabetta; Meloni, Italo; Ortúzar, Juan de Dios

    2014-01-01

    The existence of habit (leading to inertia) in the choice process has been approached in the literature in a number of ways. In transport, inertia has been studied mainly using “long panel” data, or mixed revealed and stated preference data. In these studies inertia links the choice made in two...... approaches. We assume that inertia is revealed by past behaviour and affects also the initial condition, but we recognise that past behaviour is only an indicator of habitual behaviour, the true process behind the formation of habitual behaviour being latent. We estimate a hybrid choice model using a set...... of revealed and stated mode choice preferences collected in Cagliari (Italy). We found a significant latent inertia in the revealed preference data, indicating that inertia affects the initial conditions. The latent inertia is revealed by the frequency of past behaviour but the effect of trip frequency...

  5. DESENVOLVIMENTO DE UM MÉTODO MONTE CARLO NÃO PARAMÉTRICO PARA SIMULAR FONTES RADIATIVAS PLANARES EM MODELOS COMPUTACIONAIS DE EXPOSIÇÃO

    Directory of Open Access Journals (Sweden)

    José Wilson Vieira

    2014-07-01

    Full Text Available Nos modelos computacionais de exposição (MCEs do DEN/UFPE, um fantoma (simulador antropomórfico é acoplado ao código Monte Carlo (MC EGSnrc para avaliações dosimétricas. Os modelos também precisam de um simulador da fonte emissora de radiação. Este trabalho apresenta um algoritmo MC não paramétrico de uma fonte radioativa planar, isotrópica por rotação, dependente da variável radial e da função de distribuição acumulada (FDA do problema, conhecida, mas não inversível. O algoritmo escolhe N valores da variável radial e calcula os correspondentes valores da função densidade de probabilidade (FDP e da FDA do problema. A suposição usada é que, se os valores da FDA fossem discretos, corresponderiam a frequências de raio (FR em intervalos consecutivos do domínio. Usando um gerador de números aleatórios (GNA uniformes normalizados em [0, 1, a técnica MC da inversão generalizada e interpolações lineares, foi possível obter amostras de r. Para comparações dosimétricas, foi reutilizado o MCE MSTA (Mash STAnding = fantoma MASH + EGSnrc + algoritmo baseado na FDP exponencial e montado o MSTA_FR. As implementações foram adicionadas ao software MonteCarlo, desenvolvido pelos autores e atualizado sempre que necessário. Os resultados apresentados e comentados estabelecem um novo algoritmo para uma fonte radioativa planar.

  6. Using standard serology blood tests to diagnose latent syphilis

    Directory of Open Access Journals (Sweden)

    G. L. Katunin

    2016-01-01

    Full Text Available Goal. To conduct a comparative assessment of the results of regulated serological tests obtained as a result of blood tests in patients suffering from latent syphilis. Materials and methods. The authors examined 187 patient medical records with newly diagnosed latent syphilis in FGBU GNTsDK (State Research Center for Dermatology, Venereology and Cosmetology, Health Ministry of the Russian Federation, in 2006-2015. The results of patient blood tests were analyzed with the use of non-treponemal (microprecipitation test/RPR and treponemal (passive hemagglutination test, immune-enzyme assay (IgA, IgM, IgG, IFabs, immunofluorescence test and Treponema pallidum immobilization test serology tests. Results. According to the results of blood tests of latent syphilis patients, the largest number of positive results was obtained as a result of treponemal serology tests such as immune-enzyme assay (100%, passive hemagglutination test (100% and IFabs (100%. The greatest number of negative results was observed in non-treponemal (microprecipitation test/RPR serology tests: in 136 (72.7% patients; evidently positive results (4+ test results were obtained in 8 (4.3% patients only. According to the results of a comparative analysis of blood tests in patients suffering from latent syphilis obtained with the use of treponemal serology tests, the greatest number of evidently positive results (4+ was noted for the passive hemagglutination test (67.9%. Negative treponemal test results were obtained with the use of the immunofluorescence test and Treponema pallidum immobilization test (21.9% and 11.8% of cases, respectively. Moreover, weakly positive results prevailed for the immunofluorescence test: in 65 (34.7% patients. Conclusion. These data confirm that the following treponemal tests belong to the most reliable ones for revealing patients suffering from latent syphilis: immune-enzyme assay, passive hemagglutination test and IFabs.

  7. Modeling Psychological Attributes in Psychology – An Epistemological Discussion: Network Analysis vs. Latent Variables

    Science.gov (United States)

    Guyon, Hervé; Falissard, Bruno; Kop, Jean-Luc

    2017-01-01

    Network Analysis is considered as a new method that challenges Latent Variable models in inferring psychological attributes. With Network Analysis, psychological attributes are derived from a complex system of components without the need to call on any latent variables. But the ontological status of psychological attributes is not adequately defined with Network Analysis, because a psychological attribute is both a complex system and a property emerging from this complex system. The aim of this article is to reappraise the legitimacy of latent variable models by engaging in an ontological and epistemological discussion on psychological attributes. Psychological attributes relate to the mental equilibrium of individuals embedded in their social interactions, as robust attractors within complex dynamic processes with emergent properties, distinct from physical entities located in precise areas of the brain. Latent variables thus possess legitimacy, because the emergent properties can be conceptualized and analyzed on the sole basis of their manifestations, without exploring the upstream complex system. However, in opposition with the usual Latent Variable models, this article is in favor of the integration of a dynamic system of manifestations. Latent Variables models and Network Analysis thus appear as complementary approaches. New approaches combining Latent Network Models and Network Residuals are certainly a promising new way to infer psychological attributes, placing psychological attributes in an inter-subjective dynamic approach. Pragmatism-realism appears as the epistemological framework required if we are to use latent variables as representations of psychological attributes. PMID:28572780

  8. Endogenous Opioid-Masked Latent Pain Sensitization

    DEFF Research Database (Denmark)

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

    2015-01-01

    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 chr...

  9. Perbandingan Hasil Deteksi Plagiarisme Dokumen dengan Metode Jaro-Winkler Distance dan Metode Latent Semantic Analysis

    Directory of Open Access Journals (Sweden)

    Tinaliah Tinaliah

    2018-01-01

    Full Text Available Various methods are applied in the application of plagiarism detection to help check the similarity of a document. Jaro-Winkler Distance can measure the distance between two strings. However, this method basically depends on the position of the word. Latent Semantic Analysis emphasizes the words contained in the document regardless of its linguistic character. This study compares the results of plagiarism detection using the Jaro-Winkler Distance and the Latent Semantic Analysis method. From comparing results of  Jaro-Winkler Distance method and Latent Semantic Analysis method, Jaro-Winkler Distance method is better than Latent Semantic Analysis method if using the same test data. Jaro-Winkler Distance method will give plagiarism result 100% and Latent Semantic Analysis method will give plagiarism result 97,14%. Beragam metode diterapkan dalam aplikasi deteksi plagiarisme untuk membantu mengecek tingkat kesamaan sebuah dokumen. Metode Jaro-Winkler Distance dapat mengukur kesamaan antara dua buah string dan sangat bergantung pada urutan atau posisi kata. Latent Semantic Analysis mementingkan kata-kata yang terkandung di dalam dokumen tanpa memperhatikan karakter linguistiknya. Penelitian ini melakukan perbandingan hasil deteksi plagiarisme dengan menggunakan metode Jaro-Winkler Distance dan metode Latent Semantic Analysis. Hasil pendeteksian plagiarisme dokumen menggunakan metode Jaro-Winkler Distance memberikan hasil yang lebih baik daripada metode Latent Semantic Analysis, yaitu jika data yang dibandingkan sama persis maka akan menghasilkan nilai plagiat sebesar 100%, sedangkan metode Latent Semantic Analysis menghasilkan nilai plagiat sebesar 97,14%.

  10. Latent cluster analysis of ALS phenotypes identifies prognostically differing groups.

    Directory of Open Access Journals (Sweden)

    Jeban Ganesalingam

    2009-09-01

    Full Text Available 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.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.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.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.

  11. Expressão da proteína tgfbeta1 em coração irradiado in vivo In vivo evaluation of expression of TGFbeta1 in the irradiated heart

    Directory of Open Access Journals (Sweden)

    Renato José Affonso Júnior

    2004-04-01

    Full Text Available OBJETIVO: Avaliar, no coração, por imuno-histoquímica, 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. MATERIAIS E MÉTODOS: Trinta e dois 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 0,97 Gy/min., dose única de 7 Gy 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 corações irradiados apresentaram: 1 alterações nucleares e diminuição das estriações das células musculares cardíacas; 2 aumento significante da deposição de fibras colágenas aos 90 dias depois da irradiação; 3 ativação da proteína TGFbeta1 latente em cardiomiócitos e células do conjuntivo depois da irradiação. CONCLUSÃO: Nossos resultados mostram a importância da proteína TGFbeta1 no processo de fibrose cardíaca radioinduzida e sugerem que células do parênquima (cardiomiócitos e do conjuntivo podem participar deste mecanismo atuando como fontes da proteína TGFbeta1 ativa.OBJECTIVE: To assess the latent and active TGFbeta1 localization in the heart, to evaluate whether or not radiation induces latent TGFbeta1 activation, and to study the distribution of collagen fibers in the irradiated heart. MATERIALS AND 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-body radiation dose of 7Gy, using a 60Co source at a dose rate of 0.97 Gy/min. The animals were sacrificed by cervical dislocation at 1, 14, 30 and 90 days after irradiation. RESULTS: The irradiated hearts showed: 1

  12. Visualizing Confidence Bands for Semiparametrically Estimated Nonlinear Relations among Latent Variables

    Science.gov (United States)

    Pek, Jolynn; Chalmers, R. Philip; Kok, Bethany E.; Losardo, Diane

    2015-01-01

    Structural equation mixture models (SEMMs), when applied as a semiparametric model (SPM), can adequately recover potentially nonlinear latent relationships without their specification. This SPM is useful for exploratory analysis when the form of the latent regression is unknown. The purpose of this article is to help users familiar with structural…

  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. Effect of Latent Heat Released by Freezing Droplets during Frost Wave Propagation.

    Science.gov (United States)

    Chavan, Shreyas; Park, Deokgeun; Singla, Nitish; Sokalski, Peter; Boyina, Kalyan; Miljkovic, Nenad

    2018-05-21

    Frost spreads on nonwetting surfaces during condensation frosting via an interdroplet frost wave. When a supercooled condensate water droplet freezes on a hydrophobic or superhydrophobic surface, neighboring droplets still in the liquid phase begin to evaporate. Two possible mechanisms govern the evaporation of neighboring water droplets: (1) The difference in saturation pressure of the water vapor surrounding the liquid and frozen droplets induces a vapor pressure gradient, and (2) the latent heat released by freezing droplets locally heats the substrate, leading to evaporation of nearby droplets. The relative significance of these two mechanisms is still not understood. Here, we study the significance of the latent heat released into the substrate by freezing droplets, and its effect on adjacent droplet evaporation, by studying the dynamics of individual water droplet freezing on aluminum-, copper-, and glass-based hydrophobic and superhydrophobic surfaces. The latent heat flux released into the substrate was calculated from the measured droplet sizes and the respective freezing times ( t f ), defined as the time from initial ice nucleation within the droplet to complete droplet freezing. To probe the effect of latent heat release, we performed three-dimensional transient finite element simulations showing that the transfer of latent heat to neighboring droplets is insignificant and accounts for a negligible fraction of evaporation during microscale frost wave propagation. Furthermore, we studied the effect of substrate thermal conductivity on the transfer of latent heat transfer to neighboring droplets by investigating the velocity of ice bridge formation. The velocity of the ice bridge was independent of the substrate thermal conductivity, indicating that adjacent droplet evaporation during condensation frosting is governed solely by vapor pressure gradients. This study not only provides key insights into the individual droplet freezing process but also

  15. New developing reagent for latent fingermark visualization: Fuller’s earth (Multani Mitti

    Directory of Open Access Journals (Sweden)

    Pallavi Thakur

    2016-12-01

    Full Text Available A number of methods have been reported in the literature for the development of latent fingermarks on different surfaces. This paper reports a new and simple powdering method which is non-toxic and has been employed on different substrates successfully for the development and visualization of latent fingermarks up to the time period of 6 days in varying temperature conditions. In this investigation a less expensive, simple and easily available fuller’s earth (Multani Mitti powder has been used to decipher the latent fingermarks on different substrates namely black cardboard box, clear glass, coverslip box, steel surface, laminated wooden sheet, clear plastic, colored plastic bag and surface of highlighter pen. It is observed that it gives very clear results on majority of substrates and can be successfully used for the development and visualization of latent fingermarks.

  16. Latent class joint model of ovarian function suppression and DFS for premenopausal breast cancer patients.

    Science.gov (United States)

    Zhang, Jenny J; Wang, Molin

    2010-09-30

    Breast cancer is the leading cancer in women of reproductive age; more than a quarter of women diagnosed with breast cancer in the US are premenopausal. A common adjuvant treatment for this patient population is chemotherapy, which has been shown to cause premature menopause and infertility with serious consequences to quality of life. Luteinizing-hormone-releasing hormone (LHRH) agonists, which induce temporary ovarian function suppression (OFS), has been shown to be a useful alternative to chemotherapy in the adjuvant setting for estrogen-receptor-positive breast cancer patients. LHRH agonists have the potential to preserve fertility after treatment, thus, reducing the negative effects on a patient's reproductive health. However, little is known about the association between a patient's underlying degree of OFS and disease-free survival (DFS) after receiving LHRH agonists. Specifically, we are interested in whether patients with lower underlying degrees of OFS (i.e. higher estrogen production) after taking LHRH agonists are at a higher risk for late breast cancer events. In this paper, we propose a latent class joint model (LCJM) to analyze a data set from International Breast Cancer Study Group (IBCSG) Trial VIII to investigate the association between OFS and DFS. Analysis of this data set is challenging due to the fact that the main outcome of interest, OFS, is unobservable and the available surrogates for this latent variable involve masked event and cured proportions. We employ a likelihood approach and the EM algorithm to obtain parameter estimates and present results from the IBCSG data analysis.

  17. 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.

  18. Shallow and Deep Latent Heating Modes Over Tropical Oceans Observed with TRMM PR Spectral Latent Heating Data

    Science.gov (United States)

    Takayabu, Yukari N.; Shige, Shoichi; Tao, Wei-Kuo; Hirota, Nagio

    2010-01-01

    The global hydrological cycle is central to the Earth's climate system, with rainfall and the physics of its formation acting as the key links in the cycle. Two-thirds of global rainfall occurs in the Tropics. Associated with this rainfall is a vast amount of heat, which is known as latent heat. It arises mainly due to the phase change of water vapor condensing into liquid droplets; three-fourths of the total heat energy available to the Earth's atmosphere comes from tropical rainfall. In addition, fresh water provided by tropical rainfall and its variability exerts a large impact upon the structure and motions of the upper ocean layer. Three-dimensional distributions of latent heating estimated from Tropical Rainfall Measuring Mission Precipitation Radar (TRMM PR)utilizing the Spectral Latent Heating (SLH) algorithm are analyzed. Mass-weighted and vertically integrated latent heating averaged over the tropical oceans is estimated as approx.72.6 J/s (approx.2.51 mm/day), and that over tropical land is approx.73.7 J/s (approx.2.55 mm/day), for 30degN-30degS. It is shown that non-drizzle precipitation over tropical and subtropical oceans consists of two dominant modes of rainfall systems, deep systems and congestus. A rough estimate of shallow mode contribution against the total heating is about 46.7 % for the average tropical oceans, which is substantially larger than 23.7 % over tropical land. While cumulus congestus heating linearly correlates with the SST, deep mode is dynamically bounded by large-scale subsidence. It is notable that substantial amount of rain, as large as 2.38 mm day-1 in average, is brought from congestus clouds under the large-scale subsiding circulation. It is also notable that even in the region with SST warmer than 28 oC, large-scale subsidence effectively suppresses the deep convection, remaining the heating by congestus clouds. Our results support that the entrainment of mid-to-lower-tropospheric dry air, which accompanies the large

  19. Associations between chewing lice (Insecta, Phthiraptera and albatrosses and petrels (Aves, Procellariiformes collected in Brazil Associações entre malófagos (Insecta, Phthiraptera e albatrozes e petréis (Aves, Procellariiformes capturados no Brasil

    Directory of Open Access Journals (Sweden)

    Michel P. Valim

    2006-12-01

    Full Text Available Chewing lice were searched on 197 skins of 28 species of procellariiform birds collected in Brazil. A total of 38 species of lice were found on 112 skins belonging to 22 bird species. The lice were slide-mounted and identified. A list of lice species found and their host species is given and some host-louse associations are discussed under an evolutionary perspective.Malófagos foram procurados em 197 peles de 28 espécies de aves Procellariiformes capturadas no Brasil. Um total de 38 espécies de piolhos foram encontradas em 112 peles pertencentes a 22 espécies de aves. Os piolhos foram montados em lâminas e identificados. Uma lista com as espécies de piolhos encontradas e seus hospedeiros é dada, além de algumas associações entre os piolhos e as aves serem discutidas sob uma perspectiva evolutiva.

  20. Predisposição de macieiras (Malus domestica Borkh.) com infecções virais a Cryptosporiopsis perennans (Zeller & Childs) Wollenweber em frutos e Colletotrichum gloeosporioides (Penzig. & Sacc. em folhas

    OpenAIRE

    Denis Salvati Guerra

    2007-01-01

    A cultura da macieira no Brasil ocupa cerca de 35 mil hectares com uma produção que chega, em alguns anos, a 1 milhão de toneladas. Dentre os principais vírus que infectam as plantas estão os chamados latentes Apple stem grooving virus (ASGV), Apple chlorotic leaf spot virus (ACLSV) e Apple stem pitting virus (ASPV) como também o Apple mosaic virus (ApMV). Atualmente, entre as doenças fúngicas mais importantes estão à podridão de olho de boi causadas por Cryptosporiopsis perennans e a mancha ...

  1. Comparação do teste tuberculínico e do ensaio de liberação de interferon-gama para diagnóstico de tuberculose latente em agentes comunitários de saúde do Sul do Brasil, Rio Grande do Sul, 2012

    Directory of Open Access Journals (Sweden)

    Paula Corrêa Machado

    Full Text Available OBJETIVO: comparar a capacidade de detecção de infecção latente por Mycobacterium tuberculosis em agentes comunitários de saúde (ACS com uso do teste tuberculínico (TT e do ensaio de liberação de interferon-gama (IGRA. MÉTODOS: estudo transversal realizado no município de Santa Cruz do Sul, Rio Grande do Sul, Brasil, com aplicação do TT e do IGRA em 47 ACS no período de março a junho de 2012; o TT foi considerado positivo na presença de uma induração ≥10 mm, assim como o IGRA, se houvesse concentração ≥0,35 UI/ml de interferon-gama. RESULTADOS: 12 ACS apresentaram TT positivo e 6 tiveram IGRA positivo; a concordância entre os testes foi avaliada como pobre (κ=0,063. CONCLUSÃO: apesar do número limitado de amostras, a alta discordância entre os testes evidencia a necessidade de desenvolver mais estudos que busquem encontrar uma explicação biológica para tais diferenças e avaliem a relação de custo-benefício na utilização do IGRA.

  2. Reference Gene Selection in the Desert Plant <em>Eremosparton songoricuem>m>

    Directory of Open Access Journals (Sweden)

    Dao-Yuan Zhang

    2012-06-01

    Full Text Available <em>Eremosparton songoricum em>(Litv. Vass. (<em>E. songoricumem> is a rare and extremely drought-tolerant desert plant that holds promise as a model organism for the identification of genes associated with water deficit stress. Here, we cloned and evaluated the expression of eight candidate reference genes using quantitative real-time reverse transcriptase polymerase chain reactions. The expression of these candidate reference genes was analyzed in a diverse set of 20 samples including various <em>E. songoricumem> plant tissues exposed to multiple environmental stresses. GeNorm analysis indicated that expression stability varied between the reference genes in the different experimental conditions, but the two most stable reference genes were sufficient for normalization in most conditions.<em> EsEFem> and <em>Esα-TUB> were sufficient for various stress conditions, <em>EsEF> and <em>EsACT> were suitable for samples of differing germination stages, and <em>EsGAPDH>and <em>Es>UBQ em>were most stable across multiple adult tissue samples. The <em>Es18Sem> gene was unsuitable as a reference gene in our analysis. In addition, the expression level of the drought-stress related transcription factor <em>EsDREB2em>> em>verified the utility of<em> E. songoricumem> reference genes and indicated that no single gene was adequate for normalization on its own. This is the first systematic report on the selection of reference genes in <em>E. songoricumem>, and these data will facilitate future work on gene expression in this species.

  3. A Cell Culture Model of Latent and Lytic Herpes Simplex Virus Type 1 Infection in Spiral Ganglion.

    Science.gov (United States)

    Liu, Yuehong; Li, Shufeng

    2015-01-01

    Reactivation of latent herpes simplex virus type 1 (HSV-1) in spiral ganglion neurons (SGNs) is supposed to be one of the causes of idiopathic sudden sensorineural hearing loss. This study aims to establish a cell culture model of latent and lytic HSV-1 infection in spiral ganglia. In the presence of acyclovir, primary cultures of SGNs were latently infected with HSV-1 expressing green fluorescent protein. Four days later, these cells were treated with trichostatin A (TSA), a known chemical reactivator of HSV-1. TCID50 was used to measure the titers of virus in cultures on Vero cells. RNA from cultures was detected for the presence of transcripts of ICP27 and latency-associated transcript (LAT) using reverse transcription polymerase chain reaction. There is no detectable infectious HSV-1 in latently infected cultures, whereas they could be observed in both lytically infected and latently infected/TSA-treated cultures. LAT was the only detectable transcript during latent infection, whereas lytic ICP27 transcript was detected in lytically infected and latently infected/TSA-treated cultures. Cultured SGNs can be both latently and lytically infected with HSV-1. Furthermore, latently infected SGNs can be reactivated using TSA, yielding infectious virus.

  4. The Latent Class Model as a Measurement Model for Situational Judgment Tests

    Directory of Open Access Journals (Sweden)

    Frank Rijmen

    2011-11-01

    Full Text Available In a situational judgment test, it is often debatable what constitutes a correct answer to a situation. There is currently a multitude of scoring procedures. Establishing a measurement model can guide the selection of a scoring rule. It is argued that the latent class model is a good candidate for a measurement model. Two latent class models are applied to the Managing Emotions subtest of the Mayer, Salovey, Caruso Emotional Intelligence Test: a plain-vanilla latent class model, and a second-order latent class model that takes into account the clustering of several possible reactions within each hypothetical scenario of the situational judgment test. The results for both models indicated that there were three subgroups characterised by the degree to which differentiation occurred between possible reactions in terms of perceived effectiveness. Furthermore, the results for the second-order model indicated a moderate cluster effect.

  5. Latent class analysis of the diagnostic characteristics of PCR and conventional bacteriological culture in diagnosing intramammary infections caused by <em>Staphylococcus aureusem> in dairy cows at dry off

    DEFF Research Database (Denmark)

    Cederlöf, Sara Ellinor; Toft, Nils; Aalbæk, Bent

    2012-01-01

    characteristics of PathoProof TM Mastitis PCR Assay and bacteriological culture (BC) in diagnosing bovine intramammary infections caused by S. aureus at dry off at different PCR cycle threshold (Ct)-value cut-offs. METHODS: Sterile quarter samples and non-sterile composite samples from 140 animals in seven herds...... were collected in connection with the dairy herd improvement (DHI) milk recording. All quarter samples were analyzed using BC whereas all composite samples were analyzed with PathoProof TM Mastitis PCR Assay. Latent class analysis was used to estimate test properties for PCR and BC in the absence...

  6. Prevalence of latent Mycobacterium tuberculosis infection among professionals of the primary healthcare network

    Directory of Open Access Journals (Sweden)

    Tássia Silvana Borges

    2014-06-01

    Full Text Available Objective: To estimate the prevalence of latent M. tuberculosis infection and identify characteristics related to latent infection among workers of the primary healthcare network.Methods: Cross-sectional, observational and descriptive study, conducted in 2011, included 137 basic health workers who performed their activities in a municipality. Interviews were carried out addressing characteristics of exposure at work (BCG vaccination, length of time working in the health system, potential exposure to tuberculosis, HIV infection, use of corticosteroids, diabetes, use of tobacco or alcohol and subsequently performed tuberculin skin test (TST. Data was analyzed with Fischer and Student’s t-test (p < 0.05. Results: Health professionals were mostly women (n=126, 92% with mean age of 35.3 (± 9.1 years. Among the reactors, 25 (55.5% sought medical care, and of these, 7 (28% underwent prophylactic treatment. The prevalence of latent tuberculosis was 32.8%. Of the characteristics evaluated, only smoking (OR 3.03; 95%CI 1.05-8.77 was associated with latent infection. Conclusion: The estimated prevalence of latent M. tuberculosis infection among the evaluated health workers was 32.8%. As for the characteristics studied, it was not possible to relate them to latent infection among workers in primary healthcare network, with the exception of the smoking habit. doi: 10.5020/18061230.2014.p269

  7. 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. © 2014 The British Psychological Society.

  8. Evaluation of HIV Risk Reduction and Intervention Programs via Latent Growth Model.

    Science.gov (United States)

    Wang, Jichuan; Siegal, Harvey A.; Falck, Russel S.; Carlson, Robert G.; Rahman, Ahmmed

    1999-01-01

    Demonstrates how the latent growth model can be applied to the evaluation of programs targeting HIV risk behavior among drug users. Multigroup piecewise latent growth models were fit to longitudinal data with three repeated response measures. Participants were 430 drug users and their sex partners. (SLD)

  9. A Composite Likelihood Inference in Latent Variable Models for Ordinal Longitudinal Responses

    Science.gov (United States)

    Vasdekis, Vassilis G. S.; Cagnone, Silvia; Moustaki, Irini

    2012-01-01

    The paper proposes a composite likelihood estimation approach that uses bivariate instead of multivariate marginal probabilities for ordinal longitudinal responses using a latent variable model. The model considers time-dependent latent variables and item-specific random effects to be accountable for the interdependencies of the multivariate…

  10. Full Text or Abstract? : Examining Topic Coherence Scores Using Latent Dirichlet Allocation

    NARCIS (Netherlands)

    Syed, S.; Spruit, M.

    2017-01-01

    This paper assesses topic coherence and human topic ranking of uncovered latent topics from scientific publications when utilizing the topic model latent Dirichlet allocation (LDA) on abstract and full-text data. The coherence of a topic, used as a proxy for topic quality, is based on the

  11. The Latent Structure of Attention Deficit/Hyperactivity Disorder in an Adult Sample

    Science.gov (United States)

    Marcus, David K.; Norris, Alyssa L.; Coccaro, Emil F.

    2012-01-01

    The vast majority of studies that have examined the latent structure of attention deficit/hyperactivity disorder (ADHD) in children and adolescents have concluded that ADHD has a dimensional latent structure. In other words, ADHD symptomatology exists along a continuum and there is no natural boundary or qualitative distinction (i.e., taxon) separating youth with ADHD from those with subclinical inattention or hyperactivity/impulsivity problems. Although adult ADHD appears to be less prevalent than ADHD in youth (which could suggest a more severe adult ADHD taxon), researchers have yet to examine the latent structure of ADHD in adults. The present study used a sample (N = 600) of adults who completed a self-report measure of ADHD symptoms. The taxometric analyses revealed a dimensional latent structure for inattention, hyperactivity/impulsivity, and ADHD. These findings are consistent with previous taxometric studies that examined ADHD in children and adolescents, and with contemporary polygenic and multifactorial models of ADHD. PMID:22480749

  12. Alexithymia and psychosocial problems among Italian preadolescents. A latent class analysis approach.

    Science.gov (United States)

    Mannarini, Stefania; Balottin, Laura; Toldo, Irene; Gatta, Michela

    2016-10-01

    The study, conducted on Italian preadolscents aged 11 to 13 belonging to the general population, aims to investigate the relationship between the emotional functioning, namely, alexithymia, and the risk of developing behavioral and emotional problems measured using the Strength and Difficulty Questionnaire. The latent class analysis approach allowed to identify two latent variables, accounting for the internalizing (emotional symptoms and difficulties in emotional awareness) and for the externalizing problems (conduct problems and hyperactivity, problematic relationships with peers, poor prosocial behaviors and externally oriented thinking). The two latent variables featured two latent classes: the difficulty in dealing with problems and the strength to face problems that was representative of most of the healthy participants with specific gender differences. Along with the analysis of psychopathological behaviors, the study of resilience and strengths can prove to be a key step in order to develop valuable preventive approaches to tackle psychiatric disorders. © 2016 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  13. The latent structure of attention deficit/hyperactivity disorder in an adult sample.

    Science.gov (United States)

    Marcus, David K; Norris, Alyssa L; Coccaro, Emil F

    2012-06-01

    The vast majority of studies that have examined the latent structure of attention deficit/hyperactivity disorder (ADHD) in children and adolescents have concluded that ADHD has a dimensional latent structure. In other words, ADHD symptomatology exists along a continuum and there is no natural boundary or qualitative distinction (i.e., taxon) separating youth with ADHD from those with subclinical inattention or hyperactivity/impulsivity problems. Although adult ADHD appears to be less prevalent than ADHD in youth (which could suggest a more severe adult ADHD taxon), researchers have yet to examine the latent structure of ADHD in adults. The present study used a sample (N = 600) of adults who completed a self-report measure of ADHD symptoms. The taxometric analyses revealed a dimensional latent structure for inattention, hyperactivity/impulsivity, and ADHD. These findings are consistent with previous taxometric studies that examined ADHD in children and adolescents, and with contemporary polygenic and multifactorial models of ADHD. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. New Treatment Regimen for Latent Tuberculosis Infection

    Centers for Disease Control (CDC) Podcasts

    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.

  15. Maximum likelihood estimation and EM algorithm of Copas-like selection model for publication bias correction.

    Science.gov (United States)

    Ning, Jing; Chen, Yong; Piao, Jin

    2017-07-01

    Publication bias occurs when the published research results are systematically unrepresentative of the population of studies that have been conducted, and is a potential threat to meaningful meta-analysis. The Copas selection model provides a flexible framework for correcting estimates and offers considerable insight into the publication bias. However, maximizing the observed likelihood under the Copas selection model is challenging because the observed data contain very little information on the latent variable. In this article, we study a Copas-like selection model and propose an expectation-maximization (EM) algorithm for estimation based on the full likelihood. Empirical simulation studies show that the EM algorithm and its associated inferential procedure performs well and avoids the non-convergence problem when maximizing the observed likelihood. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. Forensic Discrimination of Latent Fingerprints Using Laser-Induced Breakdown Spectroscopy (LIBS) and Chemometric Approaches.

    Science.gov (United States)

    Yang, Jun-Ho; Yoh, Jack J

    2018-01-01

    A novel technique is reported for separating overlapping latent fingerprints using chemometric approaches that combine laser-induced breakdown spectroscopy (LIBS) and multivariate analysis. The LIBS technique provides the capability of real time analysis and high frequency scanning as well as the data regarding the chemical composition of overlapping latent fingerprints. These spectra offer valuable information for the classification and reconstruction of overlapping latent fingerprints by implementing appropriate statistical multivariate analysis. The current study employs principal component analysis and partial least square methods for the classification of latent fingerprints from the LIBS spectra. This technique was successfully demonstrated through a classification study of four distinct latent fingerprints using classification methods such as soft independent modeling of class analogy (SIMCA) and partial least squares discriminant analysis (PLS-DA). The novel method yielded an accuracy of more than 85% and was proven to be sufficiently robust. Furthermore, through laser scanning analysis at a spatial interval of 125 µm, the overlapping fingerprints were reconstructed as separate two-dimensional forms.

  17. A specimen of <em>Sorex> cfr. <em>samniticus> in Barn Owl's pellets from Murge plateau (Apulia, Italy / Su di un <em>Sorex> cfr. <em>samniticus> (Insectivora, Soricidae rinvenuto in borre di <em>Tyto albaem> delle Murge (Puglia, Italia

    Directory of Open Access Journals (Sweden)

    Giovanni Ferrara

    1992-07-01

    Full Text Available Abstract In a lot of Barn Owl's pellets from the Murge plateau a specimen of <em>Sorex> sp. was detected. Thank to some morphological and morphometrical features, the cranial bones can be tentatively attributed to <em>Sorex samniticusem> Altobello, 1926. The genus <em>Sorex> was not yet included in the Apulia's fauna southwards of the Gargano district; the origin and significance of the above record is briefly discussed, the actual presence of a natural population of <em>Sorex> in the Murge being not yet proved. Riassunto Viene segnalato il rinvenimento di un esemplare di <em>Sorex> cfr. <em>samniticus> da borre di <em>Tyto albaem> delle Murge. Poiché il genere non era stato ancora segnalato nella Puglia a sud del Gargano, viene discusso il significato faunistico del reperto.

  18. Efecto de extractos vegetales de <em>Polygonum hydropiperoidesem>, <em>Solanum nigrumem> y <em>Calliandra pittieriem> sobre el gusano cogollero (<em>Spodoptera frugiperdaem>

    Directory of Open Access Journals (Sweden)

    Lizarazo H. Karol

    2008-12-01

    Full Text Available

    El gusano cogollero <em>Spodoptera frugiperdaem> es una de las plagas que más afectan los cultivos en la región de Sumapaz (Cundinamarca, Colombia. En la actualidad se controla principalmente aplicando productos de síntesis química, sin embargo la aplicación de extractos vegetales surge como una alternativa de menor impacto sobre el ambiente. Este control se emplea debido a que las plantas contienen metabolitos secundarios que pueden inhibir el desarrollo de los insectos. Por tal motivo, la presente investigación evaluó el efecto insecticida y antialimentario de extractos vegetales de barbasco <em>Polygonum hydropiperoidesem> (Polygonaceae, carbonero <em>Calliandra pittieriem> (Mimosaceae y hierba mora <em>Solanum nigrumem> (Solanaceae sobre larvas de <em>S. frugiperdaem> biotipo maíz. Se estableció una cría masiva del insecto en el laboratorio utilizando una dieta natural con hojas de maíz. Posteriormente se obtuvieron extractos vegetales utilizando solventes de alta polaridad (agua y etanol y media polaridad (diclorometano los cuales se aplicaron sobre las larvas de segundo instar. Los resultados más destacados se presentaron con extractos de <em>P. hydropiperoidesem>, obtenidos con diclorometano en sus diferentes dosis, con los cuales se alcanzó una mortalidad de 100% 12 días después de la aplicación y un efecto antialimentario representado por un consumo de follaje de maíz inferior al 4%, efectos similares a los del testigo comercial (Clorpiriphos.

  19. Space-time latent component Modeling of Geo-referenced health data

    OpenAIRE

    Lawson, Andrew B.; Song, Hae-Ryoung; Cai, Bo; Hossain, Md Monir; Huang, Kun

    2010-01-01

    Latent structure models have been proposed in many applications. For space time health data it is often important to be able to find underlying trends in time which are supported by subsets of small areas. Latent structure modeling is one approach to this analysis. This paper presents a mixture-based approach that can be appied to component selction. The analysis of a Georgia ambulatory asthma county level data set is presented and a simulation-based evaluation is made.

  20. Translating latent trends in food consumer behavior into new products

    OpenAIRE

    Gellynck, Xavier; Kühne, Bianka; Van Wezemael, Lynn; Verbeke, Wim

    2010-01-01

    For successful product development it is important to explore the latent changes in consumer behavior prior to the product development process. The identification of a latent trend before the manifestation moment can be achieved by trend analysis. Trend analysis delivers insights that explore the future in order to identify prospective consumers and new product ideas, but also includes a feeling for the currents in market and technology. Hence, the aim is to identify emerging weak signals in ...

  1. Estimators for longitudinal latent exposure models: examining measurement model assumptions.

    Science.gov (United States)

    Sánchez, Brisa N; Kim, Sehee; Sammel, Mary D

    2017-06-15

    Latent variable (LV) models are increasingly being used in environmental epidemiology as a way to summarize multiple environmental exposures and thus minimize statistical concerns that arise in multiple regression. LV models may be especially useful when multivariate exposures are collected repeatedly over time. LV models can accommodate a variety of assumptions but, at the same time, present the user with many choices for model specification particularly in the case of exposure data collected repeatedly over time. For instance, the user could assume conditional independence of observed exposure biomarkers given the latent exposure and, in the case of longitudinal latent exposure variables, time invariance of the measurement model. Choosing which assumptions to relax is not always straightforward. We were motivated by a study of prenatal lead exposure and mental development, where assumptions of the measurement model for the time-changing longitudinal exposure have appreciable impact on (maximum-likelihood) inferences about the health effects of lead exposure. Although we were not particularly interested in characterizing the change of the LV itself, imposing a longitudinal LV structure on the repeated multivariate exposure measures could result in high efficiency gains for the exposure-disease association. We examine the biases of maximum likelihood estimators when assumptions about the measurement model for the longitudinal latent exposure variable are violated. We adapt existing instrumental variable estimators to the case of longitudinal exposures and propose them as an alternative to estimate the health effects of a time-changing latent predictor. We show that instrumental variable estimators remain unbiased for a wide range of data generating models and have advantages in terms of mean squared error. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  2. Perceptions of care in women sent home in latent labor.

    Science.gov (United States)

    Hosek, Claire; Faucher, Mary Ann; Lankford, Janice; Alexander, James

    2014-01-01

    To assess perceptions of care from woman discharged from an obstetrical (OB) triage unit or a labor and delivery unit with a diagnosis of false or latent labor in order to determine factors that may increase or decrease the woman's satisfaction with care. Descriptive, convenience sample. One hundred low-income pregnant women at term presenting for care in latent labor consented to participate in a telephone survey. The survey was based on the relevant research about care of women in early labor and the Donabedian quality improvement framework assessing structure, process, and outcomes of care. Forty-one percent of women did not want to be discharged home in latent labor. Common reasons included women stating they were in too much pain or they were living too far from the birth setting. Eating, drinking, and comfort measures were the most common measures women cited that would have made them feel better when in the hospital. A reoccurring response from women was their desire for very clear and specific written instructions about how to stay comfortable at home and when to return to the hospital. Comfort measures in the birth setting, including in triage, should include a variety of options including ambulation and oral nutrition. Detailed and specific written instructions about early labor and staying comfortable while at home have value for women in this survey regarding their perceptions of care. Results from this survey of low-income women suggest that a subset of women in latent labor just do not want to go home and this may be related to having too much pain and/or travel distance to the hospital. Hospital birth settings also have an opportunity to create a care environment that provides services and embodies attributes that women report as important for their satisfaction with care in latent labor.

  3. Rapid Development of Microsatellite Markers with 454 Pyrosequencing in a Vulnerable Fish<em>,> the Mottled Skate<em>, Raja em>pulchra>

    Directory of Open Access Journals (Sweden)

    Jung-Ha Kang

    2012-06-01

    Full Text Available The mottled skate, <em>Raja pulchraem>, is an economically valuable fish. However, due to a severe population decline, it is listed as a vulnerable species by the International Union for Conservation of Nature. To analyze its genetic structure and diversity, microsatellite markers were developed using 454 pyrosequencing. A total of 17,033 reads containing dinucleotide microsatellite repeat units (mean, 487 base pairs were identified from 453,549 reads. Among 32 loci containing more than nine repeat units, 20 primer sets (62% produced strong PCR products, of which 14 were polymorphic. In an analysis of 60 individuals from two <em>R. pulchra em>populations, the number of alleles per locus ranged from 1–10, and the mean allelic richness was 4.7. No linkage disequilibrium was found between any pair of loci, indicating that the markers were independent. The Hardy–Weinberg equilibrium test showed significant deviation in two of the 28 single-loci after sequential Bonferroni’s correction. Using 11 primer sets, cross-species amplification was demonstrated in nine related species from four families within two classes. Among the 11 loci amplified from three other <em>Rajidae> family species; three loci were polymorphic. A monomorphic locus was amplified in all three <em>Rajidae> family species and the <em>Dasyatidae> family. Two <em>Rajidae> polymorphic loci amplified monomorphic target DNAs in four species belonging to the Carcharhiniformes class, and another was polymorphic in two Carcharhiniformes species.

  4. Systematic identification of latent disease-gene associations from PubMed articles.

    Science.gov (United States)

    Zhang, Yuji; Shen, Feichen; Mojarad, Majid Rastegar; Li, Dingcheng; Liu, Sijia; Tao, Cui; Yu, Yue; Liu, Hongfang

    2018-01-01

    Recent scientific advances have accumulated a tremendous amount of biomedical knowledge providing novel insights into the relationship between molecular and cellular processes and diseases. Literature mining is one of the commonly used methods to retrieve and extract information from scientific publications for understanding these associations. However, due to large data volume and complicated associations with noises, the interpretability of such association data for semantic knowledge discovery is challenging. In this study, we describe an integrative computational framework aiming to expedite the discovery of latent disease mechanisms by dissecting 146,245 disease-gene associations from over 25 million of PubMed indexed articles. We take advantage of both Latent Dirichlet Allocation (LDA) modeling and network-based analysis for their capabilities of detecting latent associations and reducing noises for large volume data respectively. Our results demonstrate that (1) the LDA-based modeling is able to group similar diseases into disease topics; (2) the disease-specific association networks follow the scale-free network property; (3) certain subnetwork patterns were enriched in the disease-specific association networks; and (4) genes were enriched in topic-specific biological processes. Our approach offers promising opportunities for latent disease-gene knowledge discovery in biomedical research.

  5. Non-destructive forensic latent fingerprint acquisition with chromatic white light sensors

    Science.gov (United States)

    Leich, Marcus; Kiltz, Stefan; Dittmann, Jana; Vielhauer, Claus

    2011-02-01

    Non-destructive latent fingerprint acquisition is an emerging field of research, which, unlike traditional methods, makes latent fingerprints available for additional verification or further analysis like tests for substance abuse or age estimation. In this paper a series of tests is performed to investigate the overall suitability of a high resolution off-the-shelf chromatic white light sensor for the contact-less and non-destructive latent fingerprint acquisition. Our paper focuses on scanning previously determined regions with exemplary acquisition parameter settings. 3D height field and reflection data of five different latent fingerprints on six different types of surfaces (HDD platter, brushed metal, painted car body (metallic and non-metallic finish), blued metal, veneered plywood) are experimentally studied. Pre-processing is performed by removing low-frequency gradients. The quality of the results is assessed subjectively; no automated feature extraction is performed. Additionally, the degradation of the fingerprint during the acquisition period is observed. While the quality of the acquired data is highly dependent on surface structure, the sensor is capable of detecting the fingerprint on all sample surfaces. On blued metal the residual material is detected; however, the ridge line structure dissolves within minutes after fingerprint placement.

  6. Reactivation of Latent HIV-1 Expression by Engineered TALE Transcription Factors.

    Science.gov (United States)

    Perdigão, Pedro; Gaj, Thomas; Santa-Marta, Mariana; Barbas, Carlos F; Goncalves, Joao

    2016-01-01

    The presence of replication-competent HIV-1 -which resides mainly in resting CD4+ T cells--is a major hurdle to its eradication. While pharmacological approaches have been useful for inducing the expression of this latent population of virus, they have been unable to purge HIV-1 from all its reservoirs. Additionally, many of these strategies have been associated with adverse effects, underscoring the need for alternative approaches capable of reactivating viral expression. Here we show that engineered transcriptional modulators based on customizable transcription activator-like effector (TALE) proteins can induce gene expression from the HIV-1 long terminal repeat promoter, and that combinations of TALE transcription factors can synergistically reactivate latent viral expression in cell line models of HIV-1 latency. We further show that complementing TALE transcription factors with Vorinostat, a histone deacetylase inhibitor, enhances HIV-1 expression in latency models. Collectively, these findings demonstrate that TALE transcription factors are a potentially effective alternative to current pharmacological routes for reactivating latent virus and that combining synthetic transcriptional activators with histone deacetylase inhibitors could lead to the development of improved therapies for latent HIV-1 infection.

  7. Reactivation of Latent HIV-1 Expression by Engineered TALE Transcription Factors.

    Directory of Open Access Journals (Sweden)

    Pedro Perdigão

    Full Text Available The presence of replication-competent HIV-1 -which resides mainly in resting CD4+ T cells--is a major hurdle to its eradication. While pharmacological approaches have been useful for inducing the expression of this latent population of virus, they have been unable to purge HIV-1 from all its reservoirs. Additionally, many of these strategies have been associated with adverse effects, underscoring the need for alternative approaches capable of reactivating viral expression. Here we show that engineered transcriptional modulators based on customizable transcription activator-like effector (TALE proteins can induce gene expression from the HIV-1 long terminal repeat promoter, and that combinations of TALE transcription factors can synergistically reactivate latent viral expression in cell line models of HIV-1 latency. We further show that complementing TALE transcription factors with Vorinostat, a histone deacetylase inhibitor, enhances HIV-1 expression in latency models. Collectively, these findings demonstrate that TALE transcription factors are a potentially effective alternative to current pharmacological routes for reactivating latent virus and that combining synthetic transcriptional activators with histone deacetylase inhibitors could lead to the development of improved therapies for latent HIV-1 infection.

  8. Latent Heat Storage Through Phase Change Materials

    Indian Academy of Sciences (India)

    IAS Admin

    reducing storage volume for different materials. The examples are numerous: ... Latent heat is an attractive way to store solar heat as it provides high energy storage density, .... Maintenance of the PCM treated fabric is easy. The melted PCM.

  9. Stress-induced light scattering method for the detection of latent flaws on fine polished glass substrates.

    Science.gov (United States)

    Sakata, Y; Sakai, K; Nonaka, K

    2014-08-01

    Fine polishing techniques, such as the chemical mechanical polishing treatment, are one of the most important technique to glass substrate manufacturing. Mechanical interaction in the form of friction occurs between the abrasive and the substrate surface during polishing, which may cause formation of latent flaws on the glass substrate surface. Fine polishing-induced latent flaws may become obvious during a subsequent cleaning process if glass surfaces are corroded away by chemical interaction with the cleaning liquid. Latent flaws thus reduce product yield. In general, non-destructive inspection techniques, such as the light-scattering methods, used to detect foreign matters on the glass substrate surface. However, it is difficult to detect latent flaws by these methods because the flaws remain closed. Authors propose a novel inspection technique for fine polishing-induced latent flaws by combining the light scattering method with stress effects, referred to as the stress-induced light scattering method (SILSM). SILSM is able to distinguish between latent flaws and particles on the surface. In this method, samples are deformed by an actuator and stress effects are induced around the tips of latent flaws. Due to the photoelastic effect, the refractive index of the material around the tip of a latent flaw is changed. This changed refractive index is in turn detected by a cooled charge-coupled device camera as variations in light scattering intensity. In this report, surface latent flaws are detected non-destructively by applying SILSM to glass substrates, and the utility of SILSM evaluated as a novel inspection technique.

  10. Repeatability and reproducibility of decisions by latent fingerprint examiners.

    Directory of Open Access Journals (Sweden)

    Bradford T Ulery

    Full Text Available The interpretation of forensic fingerprint evidence relies on the expertise of latent print examiners. We tested latent print examiners on the extent to which they reached consistent decisions. This study assessed intra-examiner repeatability by retesting 72 examiners on comparisons of latent and exemplar fingerprints, after an interval of approximately seven months; each examiner was reassigned 25 image pairs for comparison, out of total pool of 744 image pairs. We compare these repeatability results with reproducibility (inter-examiner results derived from our previous study. Examiners repeated 89.1% of their individualization decisions, and 90.1% of their exclusion decisions; most of the changed decisions resulted in inconclusive decisions. Repeatability of comparison decisions (individualization, exclusion, inconclusive was 90.0% for mated pairs, and 85.9% for nonmated pairs. Repeatability and reproducibility were notably lower for comparisons assessed by the examiners as "difficult" than for "easy" or "moderate" comparisons, indicating that examiners' assessments of difficulty may be useful for quality assurance. No false positive errors were repeated (n = 4; 30% of false negative errors were repeated. One percent of latent value decisions were completely reversed (no value even for exclusion vs. of value for individualization. Most of the inter- and intra-examiner variability concerned whether the examiners considered the information available to be sufficient to reach a conclusion; this variability was concentrated on specific image pairs such that repeatability and reproducibility were very high on some comparisons and very low on others. Much of the variability appears to be due to making categorical decisions in borderline cases.

  11. Prevalence of latent alpha-herpesviruses in Thoroughbred racing horses.

    Science.gov (United States)

    Pusterla, Nicola; Mapes, Samantha; David Wilson, W

    2012-08-01

    The objective of this study was to detect and characterize latent equine herpes virus (EHV)-1 and -4 from the submandibular (SMLN) and bronchial lymph (BLN) nodes, as well as from the trigeminal ganglia (TG) of 70 racing Thoroughbred horses submitted for necropsy following sustaining serious musculoskeletal injuries while racing. A combination of nucleic acid precipitation and pre-amplification steps was used to increase analytical sensitivity. Tissues were deemed positive for latent EHV-1 and/or -4 infection when found PCR positive for the corresponding glycoprotein B (gB) gene in the absence of detectable late structural protein gene (gB gene) mRNA. The EHV-1 genotype was also determined using a discriminatory real-time PCR assay targeting the DNA polymerase gene (ORF 30). Eighteen (25.7%) and 58 (82.8%) horses were PCR positive for the gB gene of EHV-1 and -4, respectively, in at least one of the three tissues sampled. Twelve horses were dually infected with EHV-1 and -4, two carried a latent neurotropic strain of EHV-1, six carried a non-neurotropic genotype of EHV-1 and 10 were dually infected with neurotropic and non-neurotropic EHV-1. The distribution of latent EHV-1 and -4 infection varied in the samples, with the TG found to be most commonly infected. Overall, non-neurotropic strains were more frequently detected than neurotropic strains, supporting the general consensus that non-neurotropic strains are more prevalent in horse populations, and hence the uncommon occurrence of equine herpes myeloencephalopathy. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Climate forcing and response to idealized changes in surface latent and sensible heat

    International Nuclear Information System (INIS)

    Ban-Weiss, George A; Cao Long; Pongratz, Julia; Caldeira, Ken; Bala, Govindasamy

    2011-01-01

    Land use and land cover changes affect the partitioning of latent and sensible heat, which impacts the broader climate system. Increased latent heat flux to the atmosphere has a local cooling influence known as 'evaporative cooling', but this energy will be released back to the atmosphere wherever the water condenses. However, the extent to which local evaporative cooling provides a global cooling influence has not been well characterized. Here, we perform a highly idealized set of climate model simulations aimed at understanding the effects that changes in the balance between surface sensible and latent heating have on the global climate system. We find that globally adding a uniform 1 W m -2 source of latent heat flux along with a uniform 1 W m -2 sink of sensible heat leads to a decrease in global mean surface air temperature of 0.54 ± 0.04 K. This occurs largely as a consequence of planetary albedo increases associated with an increase in low elevation cloudiness caused by increased evaporation. Thus, our model results indicate that, on average, when latent heating replaces sensible heating, global, and not merely local, surface temperatures decrease.

  13. Transcriptional regulation of latent feline immunodeficiency virus in peripheral CD4+ T-lymphocytes.

    Science.gov (United States)

    McDonnel, Samantha J; Sparger, Ellen E; Luciw, Paul A; Murphy, Brian G

    2012-05-01

    Feline immunodeficiency virus (FIV), the lentivirus of domestic cats responsible for feline AIDS, establishes a latent infection in peripheral blood CD4+ T-cells approximately eight months after experimental inoculation. In this study, cats experimentally infected with the FIV-C strain in the asymptomatic phase demonstrated an estimated viral load of 1 infected cell per approximately 10(3) CD4+ T-cells, with about 1 copy of viral DNA per cell. Approximately 1 in 10 proviral copies was capable of transcription in the asymptomatic phase. The latent FIV proviral promoter was associated with deacetylated, methylated histones, which is consistent with a condensed chromatin structure. In contrast, the transcriptionally active FIV promoter was associated with histone acetylation and demethylation. In addition, RNA polymerase II appeared to be paused on the latent viral promoter, and short promoter-proximal transcripts were detected. Our findings for the FIV promoter in infected cats are similar to results obtained in studies of human immunodeficiency virus (HIV)-1 latent proviruses in cell culture in vitro studies. Thus, the FIV/cat model may offer insights into in vivo mechanisms of HIV latency and provides a unique opportunity to test novel therapeutic interventions aimed at eradicating latent virus.

  14. 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%). Published by Elsevier Ireland Ltd.

  15. Fitting and interpreting continuous-time latent Markov models for panel data.

    Science.gov (United States)

    Lange, Jane M; Minin, Vladimir N

    2013-11-20

    Multistate models characterize disease processes within an individual. Clinical studies often observe the disease status of individuals at discrete time points, making exact times of transitions between disease states unknown. Such panel data pose considerable modeling challenges. Assuming the disease process progresses accordingly, a standard continuous-time Markov chain (CTMC) yields tractable likelihoods, but the assumption of exponential sojourn time distributions is typically unrealistic. More flexible semi-Markov models permit generic sojourn distributions yet yield intractable likelihoods for panel data in the presence of reversible transitions. One attractive alternative is to assume that the disease process is characterized by an underlying latent CTMC, with multiple latent states mapping to each disease state. These models retain analytic tractability due to the CTMC framework but allow for flexible, duration-dependent disease state sojourn distributions. We have developed a robust and efficient expectation-maximization algorithm in this context. Our complete data state space consists of the observed data and the underlying latent trajectory, yielding computationally efficient expectation and maximization steps. Our algorithm outperforms alternative methods measured in terms of time to convergence and robustness. We also examine the frequentist performance of latent CTMC point and interval estimates of disease process functionals based on simulated data. The performance of estimates depends on time, functional, and data-generating scenario. Finally, we illustrate the interpretive power of latent CTMC models for describing disease processes on a dataset of lung transplant patients. We hope our work will encourage wider use of these models in the biomedical setting. Copyright © 2013 John Wiley & Sons, Ltd.

  16. Examination of the change in latent statuses in bullying behaviors across time.

    Science.gov (United States)

    Ryoo, Ji Hoon; Wang, Cixin; Swearer, Susan M

    2015-03-01

    Involvement in bullying and victimization has been mostly studied using cross-sectional data from 1 time point. As such, much of our understanding of bullying and victimization has not captured the dynamic experiences of youth over time. To examine the change of latent statuses in bullying and victimization, we applied latent transition analysis examining self-reported bullying involvement from 1,180 students in 5th through 9th grades across 3 time points. We identified unobserved heterogeneous subgroups (i.e., latent statuses) and investigated how students transition between the unobserved subgroups over time. For victimization, 4 latent statuses were identified: frequent victim (11.23%), occasional traditional victim (28.86%), occasional cyber and traditional victim (10.34%), and infrequent victim (49.57%). For bullying behavior, 3 latent statuses were identified: frequent perpetrator (5.12%), occasional verbal/relational perpetrator (26.04%), and infrequent perpetrator (68.84%). The characteristics of the transitions were examined. The multiple-group effects of gender, grade, and first language learned on transitions across statuses were also investigated. The infrequent victim and infrequent perpetrator groups were the most stable, and the frequent victim and frequent perpetrator groups were the least stable. These findings suggest instability in perpetration and victimization over time, as well as significant changes, especially during school transition years. Findings suggest that school-based interventions need to address the heterogeneity in perpetrator and victim experiences in adolescence.

  17. Rapid quantification of the latent reservoir for HIV-1 using a viral outgrowth assay.

    Directory of Open Access Journals (Sweden)

    Gregory M Laird

    Full Text Available HIV-1 persists in infected individuals in a stable pool of resting CD4(+ T cells as a latent but replication-competent provirus. This latent reservoir is the major barrier to the eradication of HIV-1. Clinical trials are currently underway investigating the effects of latency-disrupting compounds on the persistence of the latent reservoir in infected individuals. To accurately assess the effects of such compounds, accurate assays to measure the frequency of latently infected cells are essential. The development of a simpler assay for the latent reservoir has been identified as a major AIDS research priority. We report here the development and validation of a rapid viral outgrowth assay that quantifies the frequency of cells that can release replication-competent virus following cellular activation. This new assay utilizes bead and column-based purification of resting CD4(+ T cells from the peripheral blood of HIV-1 infected patients rather than cell sorting to obtain comparable resting CD4(+ T cell purity. This new assay also utilizes the MOLT-4/CCR5 cell line for viral expansion, producing statistically comparable measurements of the frequency of latent HIV-1 infection. Finally, this new assay employs a novel quantitative RT-PCR specific for polyadenylated HIV-1 RNA for virus detection, which we demonstrate is a more sensitive and cost-effective method to detect HIV-1 replication than expensive commercial ELISA detection methods. The reductions in both labor and cost make this assay suitable for quantifying the frequency of latently infected cells in clinical trials of HIV-1 eradication strategies.

  18. A New Natural Lactone from <em>Dimocarpus> <em>longan> Lour. Seeds

    Directory of Open Access Journals (Sweden)

    Zhongjun Li

    2012-08-01

    Full Text Available A new natural product named longanlactone was isolated from <em>Dimocarpus> <em>longan> Lour. seeds. Its structure was determined as 3-(2-acetyl-1<em>H>-pyrrol-1-yl-5-(prop-2-yn-1-yldihydrofuran-2(3H-one by spectroscopic methods and HRESIMS.

  19. Purification, Characterization and Antioxidant Activities <em>in Vitroem>> em>and <em>in Vivoem> of the Polysaccharides from <em>Boletus edulisem> Bull

    Directory of Open Access Journals (Sweden)

    Yijun Fan

    2012-07-01

    Full Text Available A water-soluble polysaccharide (BEBP was extracted from <em>Boletus edulis em>Bull using hot water extraction followed by ethanol precipitation. The polysaccharide BEBP was further purified by chromatography on a DEAE-cellulose column, giving three major polysaccharide fractions termed BEBP-1, BEBP-2 and BEBP-3. In the next experiment, the average molecular weight (Mw, IR and monosaccharide compositional analysis of the three polysaccharide fractions were determined. The evaluation of antioxidant activities both <em>in vitroem> and <em>in vivo em>suggested that BEBP-3 had good potential antioxidant activity, and should be explored as a novel potential antioxidant.

  20. <em>Angiostrongylus vasorumem> in red foxes (<em>Vulpes vulpesem> and badgers (<em>Meles melesem> from Central and Northern Italy

    Directory of Open Access Journals (Sweden)

    Marta Magi

    2010-06-01

    Full Text Available Abstract During 2004-2005 and 2007-2008, 189 foxes (<em>Vulpes vulpesem> and 6 badgers (<em>Meles melesem> were collected in different areas of Central Northern Italy (Piedmont, Liguria and Tuscany and examined for <em>Angiostrongylus vasorumem> infection. The prevalence of the infection was significantly different in the areas considered, with the highest values in the district of Imperia (80%, Liguria and in Montezemolo (70%, southern Piedmont; the prevalence in Tuscany was 7%. One badger collected in the area of Imperia turned out to be infected, representing the first report of the parasite in this species in Italy. Further studies are needed to evaluate the role played by fox populations as reservoirs of infection and the probability of its spreading to domestic dogs.
    Riassunto <em>Angiostrongylus vasorumem> nella volpe (<em>Vulpes vulpesem> e nel tasso (<em>Meles melesem> in Italia centro-settentrionale. Nel 2004-2005 e 2007-2008, 189 volpi (<em>Vulpes vulpesem> e 6 tassi (<em>Meles melesem> provenienti da differenti aree dell'Italia settentrionale e centrale (Piemonte, Liguria Toscana, sono stati esaminati per la ricerca di <em>Angiostrongylus vasorumem>. La prevalenza del nematode è risultata significativamente diversa nelle varie zone, con valori elevati nelle zone di Imperia (80% e di Montezemolo (70%, provincia di Cuneo; la prevalenza in Toscana è risultata del 7%. Un tasso proveniente dall'area di Imperia è risultato positivo per A. vasorum; questa è la prima segnalazione del parassita in tale specie in Italia. Ulteriori studi sono necessari per valutare il potenziale della volpe come serbatoio e la possibilità di diffusione della parassitosi ai cani domestici.

    doi:10.4404/hystrix-20.2-4442

  1. Accounting for standard errors of vision-specific latent trait in regression models.

    Science.gov (United States)

    Wong, Wan Ling; Li, Xiang; Li, Jialiang; Wong, Tien Yin; Cheng, Ching-Yu; Lamoureux, Ecosse L

    2014-07-11

    To demonstrate the effectiveness of Hierarchical Bayesian (HB) approach in a modeling framework for association effects that accounts for SEs of vision-specific latent traits assessed using Rasch analysis. A systematic literature review was conducted in four major ophthalmic journals to evaluate Rasch analysis performed on vision-specific instruments. The HB approach was used to synthesize the Rasch model and multiple linear regression model for the assessment of the association effects related to vision-specific latent traits. The effectiveness of this novel HB one-stage "joint-analysis" approach allows all model parameters to be estimated simultaneously and was compared with the frequently used two-stage "separate-analysis" approach in our simulation study (Rasch analysis followed by traditional statistical analyses without adjustment for SE of latent trait). Sixty-six reviewed articles performed evaluation and validation of vision-specific instruments using Rasch analysis, and 86.4% (n = 57) performed further statistical analyses on the Rasch-scaled data using traditional statistical methods; none took into consideration SEs of the estimated Rasch-scaled scores. The two models on real data differed for effect size estimations and the identification of "independent risk factors." Simulation results showed that our proposed HB one-stage "joint-analysis" approach produces greater accuracy (average of 5-fold decrease in bias) with comparable power and precision in estimation of associations when compared with the frequently used two-stage "separate-analysis" procedure despite accounting for greater uncertainty due to the latent trait. Patient-reported data, using Rasch analysis techniques, do not take into account the SE of latent trait in association analyses. The HB one-stage "joint-analysis" is a better approach, producing accurate effect size estimations and information about the independent association of exposure variables with vision-specific latent traits

  2. Assessment of Genetic Fidelity in <em>Rauvolfia em>s>erpentina em>Plantlets Grown from Synthetic (Encapsulated Seeds Following <em>in Vitroem> Storage at 4 °C

    Directory of Open Access Journals (Sweden)

    Mohammad Anis

    2012-05-01

    Full Text Available An efficient method was developed for plant regeneration and establishment from alginate encapsulated synthetic seeds of <em>Rauvolfia serpentinaem>. Synthetic seeds were produced using <em>in vitroem> proliferated microshoots upon complexation of 3% sodium alginate prepared in Llyod and McCown woody plant medium (WPM and 100 mM calcium chloride. Re-growth ability of encapsulated nodal segments was evaluated after storage at 4 °C for 0, 1, 2, 4, 6 and 8 weeks and compared with non-encapsulated buds. Effects of different media <em>viz>; Murashige and Skoog medium; Lloyd and McCown woody Plant medium, Gamborg’s B5 medium and Schenk and Hildebrandt medium was also investigated for conversion into plantlets. The maximum frequency of conversion into plantlets from encapsulated nodal segments stored at 4 °C for 4 weeks was achieved on woody plant medium supplement with 5.0 μM BA and 1.0 μM NAA. Rooting in plantlets was achieved in half-strength Murashige and Skoog liquid medium containing 0.5 μM indole-3-acetic acid (IAA on filter paper bridges. Plantlets obtained from stored synseeds were hardened, established successfully <em>ex vitroem> and were morphologically similar to each other as well as their mother plant. The genetic fidelity of <em>Rauvolfia em>clones raised from synthetic seeds following four weeks of storage at 4 °C were assessed by using random amplified polymorphic<em> em>DNA (RAPD and inter-simple sequence repeat<em> em>(ISSR markers. All the RAPD and ISSR profiles from generated plantlets were monomorphic and comparable<em> em>to the mother plant, which confirms the genetic<em> em>stability among the clones. This synseed protocol could be useful for establishing a particular system for conservation, short-term storage and production of genetically identical and stable plants before it is released for commercial purposes.

  3. Sulla presenza di <em>Sorex antinoriiem>, <em>Neomys anomalusem> (Insectivora, Soricidae e <em>Talpa caecaem> (Insectivora, Talpidae in Umbria

    Directory of Open Access Journals (Sweden)

    A.M. Paci

    2003-10-01

    Full Text Available Lo scopo del contributo è di fornire un aggiornamento sulla presenza del Toporagno del Vallese <em>Sorex antinoriiem>, del Toporagno acquatico di Miller <em>Neomys anomalusem> e della Talpa cieca <em>Talpa caecaem> in Umbria, dove le specie risultano accertate ormai da qualche anno. A tal fine sono stati rivisitati i reperti collezionati e la bibliografia conosciuta. Toporagno del Vallese: elevato di recente a livello di specie da Brünner et al. (2002, altrimenti considerato sottospecie del Toporagno comune (<em>S. araneus antinoriiem>. È conservato uno di tre crani incompleti (mancano mandibole ed incisivi superiori al momento prudenzialmente riferiti a <em>Sorex> cfr. <em>antinorii>, provenienti dall?Appennino umbro-marchigiano settentrionale (dintorni di Scalocchio - PG, 590 m. s.l.m. e determinati sulla base della pigmentazione rossa degli ipoconi del M1 e M2; Toporagno acquatico di Miller: tre crani (Breda in Paci e Romano op. cit. e un esemplare intero (Paci, ined. sono stati trovati a pochi chilometri di distanza gli uni dall?altro tra i comuni di Assisi e Valfabbrica, in ambienti mediocollinari limitrofi al Parco Regionale del M.te Subasio (Perugia. In provincia di Terni la specie viene segnalata da Isotti (op. cit. per i dintorni di Orvieto. Talpa cieca: sono noti una femmina e un maschio raccolti nel comune di Pietralunga (PG, rispettivamente in una conifereta a <em>Pinus nigraem> (m. 630 s.l.m. e nelle vicinanze di un bosco misto collinare a prevalenza di <em>Quercus cerrisem> (m. 640 s.l.m.. Recentemente un terzo individuo è stato rinvenuto nel comune di Sigillo (PG, all?interno del Parco Regionale di M.te Cucco, sul margine di una faggeta a 1100 m s.l.m. In entrambi i casi l?areale della specie è risultato parapatrico con quello di <em>Talpa europaeaem>.

  4. Robust Measurement via A Fused Latent and Graphical Item Response Theory Model.

    Science.gov (United States)

    Chen, Yunxiao; Li, Xiaoou; Liu, Jingchen; Ying, Zhiliang

    2018-03-12

    Item response theory (IRT) plays an important role in psychological and educational measurement. Unlike the classical testing theory, IRT models aggregate the item level information, yielding more accurate measurements. Most IRT models assume local independence, an assumption not likely to be satisfied in practice, especially when the number of items is large. Results in the literature and simulation studies in this paper reveal that misspecifying the local independence assumption may result in inaccurate measurements and differential item functioning. To provide more robust measurements, we propose an integrated approach by adding a graphical component to a multidimensional IRT model that can offset the effect of unknown local dependence. The new model contains a confirmatory latent variable component, which measures the targeted latent traits, and a graphical component, which captures the local dependence. An efficient proximal algorithm is proposed for the parameter estimation and structure learning of the local dependence. This approach can substantially improve the measurement, given no prior information on the local dependence structure. The model can be applied to measure both a unidimensional latent trait and multidimensional latent traits.

  5. Dorsal bundle lesions do not affect latent inhibition of conditioned suppression.

    Science.gov (United States)

    Tsaltas, E; Preston, G C; Rawlins, J N; Winocur, G; Gray, J A

    1984-01-01

    Three experiments are reported which examine the effects of lesions of the dorsal ascending noradrenergic bundle (DB) on latent inhibition using a conditioned suppression procedure in rats. In none of the experiments did the DB lesion have any effect, despite changes in the extent of latent inhibition and in the control procedures used to assess it. The results are discussed in relation to the attentional theory of DB function.

  6. Managing latent tuberculosis infection and tuberculosis in children

    Directory of Open Access Journals (Sweden)

    I. Carvalho

    2018-03-01

    Full Text Available Tuberculosis (TB is a major cause of childhood morbidity and mortality worldwide. The aim of this review is to describe the management of the child with TB and latent tuberculosis infection (LTBI.To develop this article, a working group reviewed relevant epidemiological and other scientific studies and established practices in conducting LBTI and TB in children. The article describes how to manage the child with LTBI, considering transmission and infectiousness of tuberculosis, contact screening and prioritization of contacts and recommendations on treatment of children with LTBI and how to manage the child with TB considering the susceptibility of children to developing tuberculosis, epidemiology and classification of tuberculosis in children, diagnosis and treatment. Keywords: Tuberculosis, Pediatric, Childhood, Latent tuberculosis infection

  7. Latent memory facilitates relearning through molecular signaling mechanisms that are distinct from original learning.

    Science.gov (United States)

    Menges, Steven A; Riepe, Joshua R; Philips, Gary T

    2015-09-01

    A highly conserved feature of memory is that it can exist in a latent, non-expressed state which is revealed during subsequent learning by its ability to significantly facilitate (savings) or inhibit (latent inhibition) subsequent memory formation. Despite the ubiquitous nature of latent memory, the mechanistic nature of the latent memory trace and its ability to influence subsequent learning remains unclear. The model organism Aplysia californica provides the unique opportunity to make strong links between behavior and underlying cellular and molecular mechanisms. Using Aplysia, we have studied the mechanisms of savings due to latent memory for a prior, forgotten experience. We previously reported savings in the induction of three distinct temporal domains of memory: short-term (10min), intermediate-term (2h) and long-term (24h). Here we report that savings memory formation utilizes molecular signaling pathways that are distinct from original learning: whereas the induction of both original intermediate- and long-term memory in naïve animals requires mitogen activated protein kinase (MAPK) activation and ongoing protein synthesis, 2h savings memory is not disrupted by inhibitors of MAPK or protein synthesis, and 24h savings memory is not dependent on MAPK activation. Collectively, these findings reveal that during forgetting, latent memory for the original experience can facilitate relearning through molecular signaling mechanisms that are distinct from original learning. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Statistical inference based on latent ability estimates

    NARCIS (Netherlands)

    Hoijtink, H.J.A.; Boomsma, A.

    The quality of approximations to first and second order moments (e.g., statistics like means, variances, regression coefficients) based on latent ability estimates is being discussed. The ability estimates are obtained using either the Rasch, oi the two-parameter logistic model. Straightforward use

  9. Variable importance in latent variable regression models

    NARCIS (Netherlands)

    Kvalheim, O.M.; Arneberg, R.; Bleie, O.; Rajalahti, T.; Smilde, A.K.; Westerhuis, J.A.

    2014-01-01

    The quality and practical usefulness of a regression model are a function of both interpretability and prediction performance. This work presents some new graphical tools for improved interpretation of latent variable regression models that can also assist in improved algorithms for variable

  10. Space-time latent component modeling of geo-referenced health data.

    Science.gov (United States)

    Lawson, Andrew B; Song, Hae-Ryoung; Cai, Bo; Hossain, Md Monir; Huang, Kun

    2010-08-30

    Latent structure models have been proposed in many applications. For space-time health data it is often important to be able to find the underlying trends in time, which are supported by subsets of small areas. Latent structure modeling is one such approach to this analysis. This paper presents a mixture-based approach that can be applied to component selection. The analysis of a Georgia ambulatory asthma county-level data set is presented and a simulation-based evaluation is made. Copyright (c) 2010 John Wiley & Sons, Ltd.

  11. Confidence Intervals for a Semiparametric Approach to Modeling Nonlinear Relations among Latent Variables

    Science.gov (United States)

    Pek, Jolynn; Losardo, Diane; Bauer, Daniel J.

    2011-01-01

    Compared to parametric models, nonparametric and semiparametric approaches to modeling nonlinearity between latent variables have the advantage of recovering global relationships of unknown functional form. Bauer (2005) proposed an indirect application of finite mixtures of structural equation models where latent components are estimated in the…

  12. Four Novel Cellulose Synthase (CESA Genes from <em>Birch> (<em>Betula platyphylla em>Suk. Involved in Primary and Secondary Cell Wall Biosynthesis

    Directory of Open Access Journals (Sweden)

    Xuemei Liu

    2012-09-01

    Full Text Available Cellulose synthase (CESA, which is an essential catalyst for the generation of plant cell wall biomass, is mainly encoded by the <em>CesA> gene family that contains ten or more members. In this study; four full-length cDNAs encoding CESA were isolated from<em> Betula platyphyllaem> Suk., which is an important timber species, using RT-PCR combined with the RACE method and were named as <em>BplCesA3em>, <em>−4em>,> −7 em>and> −8em>. These deduced CESAs contained the same typical domains and regions as their <em>Arabidopsis> homologs. The cDNA lengths differed among these four genes, as did the locations of the various protein domains inferred from the deduced amino acid sequences, which shared amino acid sequence identities ranging from only 63.8% to 70.5%. Real-time RT-PCR showed that all four <em>BplCesAs> were expressed at different levels in diverse tissues. Results indicated that BplCESA8 might be involved in secondary cell wall biosynthesis and floral development. BplCESA3 appeared in a unique expression pattern and was possibly involved in primary cell wall biosynthesis and seed development; it might also be related to the homogalacturonan synthesis. BplCESA7 and BplCESA4 may be related to the formation of a cellulose synthase complex and participate mainly in secondary cell wall biosynthesis. The extremely low expression abundance of the four BplCESAs in mature pollen suggested very little involvement of them in mature pollen formation in <em>Betula>. The distinct expression pattern of the four <em>BplCesAs> suggested they might participate in developments of various tissues and that they are possibly controlled by distinct mechanisms in <em>Betula.>

  13. 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

  14. Microsatellite Loci in the Gypsophyte <em>Lepidium subulatum em>(Brassicaceae, and Transferability to Other <em>Lepidieae>

    Directory of Open Access Journals (Sweden)

    José Gabriel Segarra-Moragues

    2012-09-01

    Full Text Available Polymorphic microsatellite markers were developed for the Ibero-North African, strict gypsophyte <em>Lepidium subulatumem> to unravel the effects of habitat fragmentation in levels of genetic diversity, genetic structure and gene flow among its populations. Using 454 pyrosequencing 12 microsatellite loci including di- and tri-nucleotide repeats were characterized in <em>L. subulatumem>. They amplified a total of 80 alleles (2–12 alleles per locus in a sample of 35 individuals of <em>L. subulatumem>, showing relatively high levels of genetic diversity, <em>H>O = 0.645, <em>H>E = 0.627. Cross-species transferability of all 12 loci was successful for the Iberian endemics <em>Lepidium cardaminesem>, <em>Lepidium stylatumem>, and the widespread, <em>Lepidium graminifoliumem> and one species each of two related genera, <em>Cardaria drabaem> and <em>Coronopus didymusem>. These microsatellite primers will be useful to investigate genetic diversity, population structure and to address conservation genetics in species of <em>Lepidium>.

  15. Estimating Non-Normal Latent Trait Distributions within Item Response Theory Using True and Estimated Item Parameters

    Science.gov (United States)

    Sass, D. A.; Schmitt, T. A.; Walker, C. M.

    2008-01-01

    Item response theory (IRT) procedures have been used extensively to study normal latent trait distributions and have been shown to perform well; however, less is known concerning the performance of IRT with non-normal latent trait distributions. This study investigated the degree of latent trait estimation error under normal and non-normal…

  16. Treatment of Latent Tuberculosis Infection

    OpenAIRE

    Tang, Patrick; Johnston, James

    2017-01-01

    Opinion statement The treatment of latent tuberculosis infection (LTBI) is an essential component of tuberculosis (TB) elimination in regions that have a low incidence of TB. However, the decision to treat individuals with LTBI must consider the limitations of current diagnostic tests for LTBI, the risk of developing active TB disease, the potential adverse effects from chemoprophylactic therapy, and the importance of treatment adherence. When an individual has been diagnosed with LTBI and ac...

  17. The latent structure of oppositional defiant disorder in children and adults.

    Science.gov (United States)

    Barry, Tammy D; Marcus, David K; Barry, Christopher T; Coccaro, Emil F

    2013-12-01

    An understanding of the latent structure of oppositional defiant disorder (ODD) is essential for better developing causal models, improving diagnostic and assessment procedures, and enhancing treatments for the disorder. Although much research has focused on ODD-including recent studies informing the diagnostic criteria for DSM-5-research examining the latent structure of ODD is sparse, and no known study has specifically undertaken a taxometric analysis to address the issue of whether ODD is a categorical or dimensional construct. To address this gap, the authors conducted two separate studies using a set of taxometric analyses with data from the NICHD Study of Early Child Care and Youth Development (child study; n = 969) and with data from a large mixed sample of adults, which included participants reporting psychiatric difficulties as well as healthy controls (adult study; n = 600). The results of a variety of non-redundant analyses across both studies revealed a dimensional latent structure for ODD symptoms among both children and adults. These findings are consistent with previous studies that have examined latent structure of related constructs (e.g., aggression, antisocial behavior) as well as studies that have examined the dimensional versus categorical structure of ODD using methods other than taxometric analysis. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Representações de masculinidades latentes em aulas de física do ensino médio

    Directory of Open Access Journals (Sweden)

    Josimeire M. Julio

    2009-01-01

    Full Text Available El estudio caracteriza aspectos latentes de masculinidades que traen implicaciones para el aprendizaje individual y colectivo de una clase de la escuela secundaria. Clases de física del primer año de una escuela secundaria fueron acompañadas a lo largo de un año. A microanálisis de una secuencia de seis clases - gravadas en audio y en video - envolviendo una actividad que simula el trabajo de una comunidad científica, caracteriza las interacciones predominantes entre los jóvenes. Las masculinidades destacadas se movilizan en torno del estímulo frente a situaciones desafiantes y de competición, de la curiosidad por el fenómeno investigado, del desafío a las reglas establecidas en la conducción de la actividad. Entre las implicaciones del estudio, se destaca la necesidad de tener en cuenta las manifestaciones de masculinidades que puedan comprometer el desarrollo de las actividades en la clase y el funcionamiento de los grupos de aprendizaje.

  19. Building latent class trees, with an application to a study of social capital

    NARCIS (Netherlands)

    van den Bergh, M.; Schmittmann, V.D.; Vermunt, J.K.

    2017-01-01

    Researchers use latent class (LC) analysis to derive meaningful clusters from sets of categorical variables. However, especially when the number of classes required to obtain a good fit is large, interpretation of the latent classes may not be straightforward. To overcome this problem, we propose an

  20. Cross-Informant Agreement on Child and Adolescent Withdrawn Behavior: A Latent Class Approach

    Science.gov (United States)

    Rubin, David H.; Althoff, Robert R.; Walkup, John T.; Hudziak, James J.

    2013-01-01

    Withdrawn behavior (WB) relates to many developmental outcomes, including pervasive developmental disorders, anxiety, depression, psychosis, personality disorders and suicide. No study has compared the latent profiles of different informants' reports on WB. This study uses multi-informant latent class analyses (LCA) of the child behavior checklist…

  1. Discriminative latent models for recognizing contextual group activities.

    Science.gov (United States)

    Lan, Tian; Wang, Yang; Yang, Weilong; Robinovitch, Stephen N; Mori, Greg

    2012-08-01

    In this paper, we go beyond recognizing the actions of individuals and focus on group activities. This is motivated from the observation that human actions are rarely performed in isolation; the contextual information of what other people in the scene are doing provides a useful cue for understanding high-level activities. We propose a novel framework for recognizing group activities which jointly captures the group activity, the individual person actions, and the interactions among them. Two types of contextual information, group-person interaction and person-person interaction, are explored in a latent variable framework. In particular, we propose three different approaches to model the person-person interaction. One approach is to explore the structures of person-person interaction. Differently from most of the previous latent structured models, which assume a predefined structure for the hidden layer, e.g., a tree structure, we treat the structure of the hidden layer as a latent variable and implicitly infer it during learning and inference. The second approach explores person-person interaction in the feature level. We introduce a new feature representation called the action context (AC) descriptor. The AC descriptor encodes information about not only the action of an individual person in the video, but also the behavior of other people nearby. The third approach combines the above two. Our experimental results demonstrate the benefit of using contextual information for disambiguating group activities.

  2. Residual Structures in Latent Growth Curve Modeling

    Science.gov (United States)

    Grimm, Kevin J.; Widaman, Keith F.

    2010-01-01

    Several alternatives are available for specifying the residual structure in latent growth curve modeling. Two specifications involve uncorrelated residuals and represent the most commonly used residual structures. The first, building on repeated measures analysis of variance and common specifications in multilevel models, forces residual variances…

  3. Constituents from <em>Vigna em>vexillata> and Their Anti-Inflammatory Activity

    Directory of Open Access Journals (Sweden)

    Guo-Feng Chen

    2012-08-01

    Full Text Available The seeds of <em>Vigna em>genus are important food resources and there have already been many reports regarding their bioactivities. In our preliminary bioassay, the chloroform layer of methanol extracts of<em> V. vexillata em>demonstrated significant anti-inflammatory bioactivity. Therefore, the present research is aimed to purify and identify the anti-inflammatory principles of <em>V. vexillataem>. One new sterol (1 and two new isoflavones (2,3 were reported from the natural sources for the first time and their chemical structures were determined by the spectroscopic and mass spectrometric analyses. In addition, 37 known compounds were identified by comparison of their physical and spectroscopic data with those reported in the literature. Among the isolates, daidzein (23, abscisic acid (25, and quercetin (40 displayed the most significant inhibition of superoxide anion generation and elastase release.

  4. Bayesian modeling of ChIP-chip data using latent variables.

    KAUST Repository

    Wu, Mingqi

    2009-10-26

    BACKGROUND: The ChIP-chip technology has been used in a wide range of biomedical studies, such as identification of human transcription factor binding sites, investigation of DNA methylation, and investigation of histone modifications in animals and plants. Various methods have been proposed in the literature for analyzing the ChIP-chip data, such as the sliding window methods, the hidden Markov model-based methods, and Bayesian methods. Although, due to the integrated consideration of uncertainty of the models and model parameters, Bayesian methods can potentially work better than the other two classes of methods, the existing Bayesian methods do not perform satisfactorily. They usually require multiple replicates or some extra experimental information to parametrize the model, and long CPU time due to involving of MCMC simulations. RESULTS: In this paper, we propose a Bayesian latent model for the ChIP-chip data. The new model mainly differs from the existing Bayesian models, such as the joint deconvolution model, the hierarchical gamma mixture model, and the Bayesian hierarchical model, in two respects. Firstly, it works on the difference between the averaged treatment and control samples. This enables the use of a simple model for the data, which avoids the probe-specific effect and the sample (control/treatment) effect. As a consequence, this enables an efficient MCMC simulation of the posterior distribution of the model, and also makes the model more robust to the outliers. Secondly, it models the neighboring dependence of probes by introducing a latent indicator vector. A truncated Poisson prior distribution is assumed for the latent indicator variable, with the rationale being justified at length. CONCLUSION: The Bayesian latent method is successfully applied to real and ten simulated datasets, with comparisons with some of the existing Bayesian methods, hidden Markov model methods, and sliding window methods. The numerical results indicate that the

  5. Synthesis, Crystal Structure and Luminescent Property of Cd (II Complex with <em>N-Benzenesulphonyl-L>-leucine

    Directory of Open Access Journals (Sweden)

    Xishi Tai

    2012-09-01

    Full Text Available A new trinuclear Cd (II complex [Cd3(L6(2,2-bipyridine3] [L =<em> Nem>-phenylsulfonyl-L>-leucinato] has been synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction analysis. The results show that the complex belongs to the orthorhombic, space group<em> Pem>212121 with<em> aem> = 16.877(3 Å, <em>b> em>= 22.875(5 Å, <em>c em>= 29.495(6 Å, <em>α> em>= <emem>= <emem>= 90°, <em>V> em>= 11387(4 Å3, <em>Z> em>= 4, <em>Dc>= 1.416 μg·m−3, <emem>= 0.737 mm−1, <em>F> em>(000 = 4992, and final <em>R>1 = 0.0390, <em>ωR>2 = 0.0989. The complex comprises two seven-coordinated Cd (II atoms, with a N2O5 distorted pengonal bipyramidal coordination environment and a six-coordinated Cd (II atom, with a N2O4 distorted octahedral coordination environment. The molecules form one dimensional chain structure by the interaction of bridged carboxylato groups, hydrogen bonds and p-p interaction of 2,2-bipyridine. The luminescent properties of the Cd (II complex and <em>N-Benzenesulphonyl-L>-leucine in solid and in CH3OH solution also have been investigated.

  6. <em>N>-Substituted 5-Chloro-6-phenylpyridazin-3(2<em>H>-ones: Synthesis, Insecticidal Activity Against <em>Plutella xylostella em>(L. and SAR Study

    Directory of Open Access Journals (Sweden)

    Song Yang

    2012-08-01

    Full Text Available A series of <em>N>-substituted 5-chloro-6-phenylpyridazin-3(2<em>H>-one derivatives were synthesized based on our previous work; all compounds were characterized by spectral data and tested for <em>in vitroem> insecticidal activity against <em>Plutella xylostellaem>. The results showed that the synthesized pyridazin-3(2<em>H>-one compounds possessed good insecticidal activities, especially the compounds 4b, 4d, and 4h which showed > 90% activity at 100 mg/L. The structure-activity relationships (SAR for these compounds were also discussed.

  7. Homeostatic proliferation fails to efficiently reactivate HIV-1 latently infected central memory CD4+ T cells.

    Directory of Open Access Journals (Sweden)

    Alberto Bosque

    2011-10-01

    Full Text Available Homeostatic proliferation ensures the longevity of central memory T-cells by inducing cell proliferation in the absence of cellular differentiation or activation. This process is governed mainly by IL-7. Central memory T-cells can also be stimulated via engagement of the T-cell receptor, leading to cell proliferation but also activation and differentiation. Using an in vitro model of HIV-1 latency, we have examined in detail the effects of homeostatic proliferation on latently infected central memory T cells. We have also used antigenic stimulation via anti-CD3/anti-CD28 antibodies and established a comparison with a homeostatic proliferation stimulus, to evaluate potential differences in how either treatment affects the dynamics of latent virus populations. First, we show that homeostatic proliferation, as induced by a combination of IL-2 plus IL-7, leads to partial reactivation of latent HIV-1 but is unable to reduce the size of the reservoir in vitro. Second, latently infected cells are able to homeostatically proliferate in the absence of viral reactivation or cell differentiation. These results indicate that IL-2 plus IL-7 may induce a detrimental effect by favoring the maintenance of the latent HIV-1 reservoir. On the other hand, antigenic stimulation efficiently reactivated latent HIV-1 in cultured central memory cells and led to depletion of the latently infected cells via virus-induced cell death.

  8. Substantiation for Approaches to Treatment of Latent Autoimmune Diabetes in Adults

    Directory of Open Access Journals (Sweden)

    T.M. Tykhonova

    2014-10-01

    Conclusions. Analysis of carbohydrate metabolism on the manifestation stage and over time development of latent autoimmune diabetes in adults as well as reduction of β-cells insulin-producing function associated with autoimmune insulitis and progressing while the development of this form of disease, substantiate the rational for insulin administration as this form of diabetes has been diagnosed. If patients with latent autoimmune diabetes in adults have metabolic syndrome clusters it is quite reasonable to add metformin to insulin.

  9. Extra Heat Loss Through Light Weight Roofs Due to Latent Heat

    DEFF Research Database (Denmark)

    Rode, Carsten

    1996-01-01

    that changes phase at the terminals of its passage.Note however, that convection of air most often will have an important effect on the overall heat flow - but that is a different topic.Macroscopic latent heat transferConsider the following scenario: Initially, moisture is present in its condensed or frozen......This report is one in a series of papers in Task 5 of IEA Annex 24 on how moisture and air movements affect the energy performance of building constructions. The effect of latent heat flow will be demonstrated by means of an example: a light weight flat roof.Latent heat flow is one of three...... processes by which moisture affects energy performance:Higher thermal conductivityMoist materials have higher thermal con-ductivity than when they are dry. This is because thermally conducting moisture replaces the better insulating air in the pores of the materials. Moisture also enhan-ces the thermal...

  10. Do gender and directness of trauma exposure moderate PTSD's latent structure?

    Science.gov (United States)

    Frankfurt, Sheila B; Armour, Cherie; Contractor, Ateka A; Elhai, Jon D

    2016-11-30

    The PTSD diagnosis and latent structure were substantially revised in the transition from DSM-IV to DSM-5. However, three alternative models (i.e., anhedonia model, externalizing behavior model, and hybrid model) of PTSD fit the DSM-5 symptom criteria better than the DSM-5 factor model. Thus, the psychometric performance of the DSM-5 and alternative models' PTSD factor structure needs to be critically evaluated. The current study examined whether gender or trauma directness (i.e., direct or indirect trauma exposure) moderates the PTSD latent structure when using the DSM-5 or alternative models. Model performance was evaluated with measurement invariance testing procedures on a large undergraduate sample (n=455). Gender and trauma directness moderated the DSM-5 PTSD and externalizing behavior model and did not moderate the anhedonia and hybrid models' latent structure. Clinical implications and directions for future research are discussed. Published by Elsevier Ireland Ltd.

  11. Pre-clinical cognitive phenotypes for Alzheimer disease: a latent profile approach.

    Science.gov (United States)

    Hayden, Kathleen M; Kuchibhatla, Maragatha; Romero, Heather R; Plassman, Brenda L; Burke, James R; Browndyke, Jeffrey N; Welsh-Bohmer, Kathleen A

    2014-11-01

    Cognitive profiles for pre-clinical Alzheimer disease (AD) can be used to identify groups of individuals at risk for disease and better characterize pre-clinical disease. Profiles or patterns of performance as pre-clinical phenotypes may be more useful than individual test scores or measures of global decline. To evaluate patterns of cognitive performance in cognitively normal individuals to derive latent profiles associated with later onset of disease using a combination of factor analysis and latent profile analysis. The National Alzheimer Coordinating Centers collect data, including a battery of neuropsychological tests, from participants at 29 National Institute on Aging-funded Alzheimer Disease Centers across the United States. Prior factor analyses of this battery demonstrated a four-factor structure comprising memory, attention, language, and executive function. Factor scores from these analyses were used in a latent profile approach to characterize cognition among a group of cognitively normal participants (N = 3,911). Associations between latent profiles and disease outcomes an average of 3 years later were evaluated with multinomial regression models. Similar analyses were used to determine predictors of profile membership. Four groups were identified; each with distinct characteristics and significantly associated with later disease outcomes. Two groups were significantly associated with development of cognitive impairment. In post hoc analyses, both the Trail Making Test Part B, and a contrast score (Delayed Recall - Trails B), significantly predicted group membership and later cognitive impairment. Latent profile analysis is a useful method to evaluate patterns of cognition in large samples for the identification of preclinical AD phenotypes; comparable results, however, can be achieved with very sensitive tests and contrast scores. Copyright © 2014 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

  12. Sensible and latent heat forced divergent circulations in the West African Monsoon System

    Science.gov (United States)

    Hagos, S.; Zhang, C.

    2008-12-01

    Field properties of divergent circulation are utilized to identify the roles of various diabatic processes in forcing moisture transport in the dynamics of the West African Monsoon and its seasonal cycle. In this analysis, the divergence field is treated as a set of point sources and is partitioned into two sub-sets corresponding to latent heat release and surface sensible heat flux at each respective point. The divergent circulation associated with each set is then calculated from the Poisson's equation using Gauss-Seidel iteration. Moisture transport by each set of divergent circulation is subsequently estimated. The results show different roles of the divergent circulations forced by surface sensible and latent heating in the monsoon dynamics. Surface sensible heating drives a shallow meridional circulation, which transports moisture deep into the continent at the polar side of the monsoon rain band and thereby promotes the seasonal northward migration of monsoon precipitation during the monsoon onset season. In contrast, the circulation directly associated with latent heating is deep and the corresponding moisture convergence is within the region of precipitation. Latent heating also induces dry air advection from the north. Neither effect promotes the seasonal northward migration of precipitation. The relative contributions of the processes associated with latent and sensible heating to the net moisture convergence, and hence the seasonal evolution of monsoon precipitation, depend on the background moisture.

  13. Some children with autism have latent social skills that can be tested

    Czech Academy of Sciences Publication Activity Database

    Hrdlička, M.; Urbánek, Tomáš; Vacová, M.; Beranová, Š.; Dudová, I.

    2017-01-01

    Roč. 13, March (2017), s. 827-833 ISSN 1178-2021 Institutional support: RVO:68081740 Keywords : autism * latent social skills * Autism Diagnostic Interview – Revised * Autism Diagnostic Observation Schedule * prediction Subject RIV: AN - Psychology OBOR OECD: Psychology (including human - machine relations) Impact factor: 2.198, year: 2016 https://www.dovepress.com/some-children-with- autism -have-latent-social-skills-that-can-be-tested-peer-reviewed-article-NDT

  14. Some children with autism have latent social skills that can be tested

    Czech Academy of Sciences Publication Activity Database

    Hrdlička, M.; Urbánek, Tomáš; Vacová, M.; Beranová, Š.; Dudová, I.

    2017-01-01

    Roč. 13, March (2017), s. 827-833 ISSN 1178-2021 Institutional support: RVO:68081740 Keywords : autism * latent social skills * Autism Diagnostic Interview – Revised * Autism Diagnostic Observation Schedule * prediction Subject RIV: AN - Psychology OBOR OECD: Psychology (including human - machine relations) Impact factor: 2.198, year: 2016 https://www.dovepress.com/some-children-with-autism-have-latent- social -skills-that-can-be-tested-peer-reviewed-article-NDT

  15. Influence of WFIKKN1 on BMP1-mediated activation of latent myostatin.

    Science.gov (United States)

    Szláma, György; Vásárhelyi, Viktor; Trexler, Mária; Patthy, László

    2016-12-01

    The NTR domain of WFIKKN1 protein has been shown to have significant affinity for the prodomain regions of promyostatin and latent myostatin but the biological significance of these interactions remained unclear. In view of its role as a myostatin antagonist, we tested the assumption that WFIKKN1 inhibits the release of myostatin from promyostatin and/or latent myostatin. WFIKKN1 was found to have no effect on processing of promyostatin by furin, the rate of cleavage of latent myostatin by BMP1, however, was significantly enhanced in the presence of WFIKKN1 and this enhancer activity was superstimulated by heparin. Unexpectedly, WFIKKN1 was also cleaved by BMP1 and our studies have shown that the KKN1 fragment generated by BMP1-cleavage of WFIKKN1 contributes most significantly to the observed enhancer activity. Analysis of a pro-TGF-β -based homology model of homodimeric latent myostatin revealed that the BMP1-cleavage sites are buried and not readily accessible to BMP1. In view of this observation, the most plausible explanation for the BMP1-enhancer activity of the KKN1 fragment is that it shifts a conformational equilibrium of latent myostatin from the closed circular structure of the homodimer to a more open form, making the cleavage sites more accessible to BMP1. On the other hand, the observation that the enhancer activity of KKN1 is superstimulated in the presence of heparin is explained by the fact KKN1, latent myostatin, and BMP1 have affinity for heparin and these interactions with heparin increase the local concentrations of the reactants thereby facilitating the action of BMP1. Furin: EC 3.4.21.75; BMP1, bone morphogentic protein 1 or procollagen C-endopeptidase: EC 3.4.24.19. © 2016 The Authors. The FEBS Journal published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.

  16. Latent factor structure of a behavioral economic marijuana demand curve.

    Science.gov (United States)

    Aston, Elizabeth R; Farris, Samantha G; MacKillop, James; Metrik, Jane

    2017-08-01

    Drug demand, or relative value, can be assessed via analysis of behavioral economic purchase task performance. Five demand indices are typically obtained from drug purchase tasks. The goal of this research was to determine whether metrics of marijuana reinforcement from a marijuana purchase task (MPT) exhibit a latent factor structure that efficiently characterizes marijuana demand. Participants were regular marijuana users (n = 99; 37.4% female, 71.5% marijuana use days [5 days/week], 15.2% cannabis dependent) who completed study assessments, including the MPT, during a baseline session. Principal component analysis was used to examine the latent structure underlying MPT indices. Concurrent validity was assessed via examination of relationships between latent factors and marijuana use, past quit attempts, and marijuana expectancies. A two-factor solution was confirmed as the best fitting structure, accounting for 88.5% of the overall variance. Factor 1 (65.8% variance) reflected "Persistence," indicating sensitivity to escalating marijuana price, which comprised four MPT indices (elasticity, O max , P max , and breakpoint). Factor 2 (22.7% variance) reflected "Amplitude," indicating the amount consumed at unrestricted price (intensity). Persistence factor scores were associated with fewer past marijuana quit attempts and lower expectancies of negative use outcomes. Amplitude factor scores were associated with more frequent use, dependence symptoms, craving severity, and positive marijuana outcome expectancies. Consistent with research on alcohol and cigarette purchase tasks, the MPT can be characterized with a latent two-factor structure. Thus, demand for marijuana appears to encompass distinct dimensions of price sensitivity and volumetric consumption, with differential relations to other aspects of marijuana motivation.

  17. Mental toughness latent profiles in endurance athletes.

    Directory of Open Access Journals (Sweden)

    Joanna S Zeiger

    Full Text Available Mental toughness in endurance athletes, while an important factor for success, has been scarcely studied. An online survey was used to examine eight mental toughness factors in endurance athletes. The study aim was to determine mental toughness profiles via latent profile analysis in endurance athletes and whether associations exist between the latent profiles and demographics and sports characteristics. Endurance athletes >18 years of age were recruited via social media outlets (n = 1245, 53% female. Mental toughness was measured using the Sports Mental Toughness Questionnaire (SMTQ, Psychological Performance Inventory-Alternative (PPI-A, and self-esteem was measured using the Rosenberg Self-Esteem Scale (RSE. A three-class solution emerged, designated as high mental toughness (High MT, moderate mental toughness (Moderate MT and low mental toughness (Low MT. ANOVA tests showed significant differences between all three classes on all 8 factors derived from the SMTQ, PPI-A and the RSE. There was an increased odds of being in the High MT class compared to the Low MT class for males (OR = 1.99; 95% CI, 1.39, 2.83; P<0.001, athletes who were over 55 compared to those who were 18-34 (OR = 2.52; 95% CI, 1.37, 4.62; P<0.01, high sports satisfaction (OR = 8.17; 95% CI, 5.63, 11.87; P<0.001, and high division placement (OR = 2.18; 95% CI, 1.46,3.26; P<0.001. The data showed that mental toughness latent profiles exist in endurance athletes. High MT is associated with demographics and sports characteristics. Mental toughness screening in athletes may help direct practitioners with mental skills training.

  18. INFLUÊNCIA ESTOICA NA CONCEPÇÃO DE <em>STATUS> E <em>DICTUM> COMO <em> QUASI RES EM> (ὡσανεì τινά EM ABERLARDO STOIC INFLUENCE IN ABELARD'S CONCEPTION OF <em>STATUS> AND <em>DICTUM> AS <em>QUASI RESem> (ὡσανεì τινά.

    Directory of Open Access Journals (Sweden)

    Guy Hamelin

    2011-09-01

    Full Text Available Na sua obra, Pedro Abelardo (1079-1142 destaca duas noções metafísicas que fundamentam sua teoria lógica: o <em style="mso-bidi-font-style: normal;">statusem> e o <em style="mso-bidi-font-style: normal;">dictum propositionisem>, ao causar, respectivamente, a imposição (<em style="mso-bidi-font-style: normal;">impositioem> dos termos universais e o valor de verdade das proposições. Trata-se de expressões que se referem a naturezas ontológicas peculiares, na medida em que não são consideradas coisas (<em style="mso-bidi-font-style: normal;">resem>, mesmo que constituem causas. Todavia, também não são nada. Abelardo as chama de ‘quase coisas’ (<em style="mso-bidi-font-style: normal;">quasi resem>. No presente artigo, explicamos, primeiro, essas duas noções essenciais da lógica abelardiana, antes de tentar, em seguida, encontrar a fonte dessa metafísica particular. Em oposição a comentadores importantes da lógica de Abelardo, que estimam que haja uma forte influência platônica sobre essa concepção específica, defendemos antes, com apoio de textos significativos e de acordo com o nominalismo abelardiano, que a maior ascendência sobre a metafísica do nosso autor é a do estoicismo, sobretudo, antigo.In his work, Peter Abelard (1079-1142 highlights two metaphysical notions, which sustain his logical theory: the <em>status> and the <em>dictum propositionisem>, causing respectively both the imposition (<em>impositio> of universal terms and the thuth-value of propositions. Both expressions refer to peculiar ontological natures, in so far as they are not considered things (<em>res>, even if they constitute causes. Nevertheless, neither are they ‘nothing’. Abelard calls them ‘quasi-things’ (<em>quasi resem>. In the present article, we expound first these two essential notions of Abelardian logic before then trying to find the source of this particular metaphysics. Contrary to some important

  19. Polarization-based and specular-reflection-based noncontact latent fingerprint imaging and lifting

    Science.gov (United States)

    Lin, Shih-Schön; Yemelyanov, Konstantin M.; Pugh, Edward N., Jr.; Engheta, Nader

    2006-09-01

    In forensic science the finger marks left unintentionally by people at a crime scene are referred to as latent fingerprints. Most existing techniques to detect and lift latent fingerprints require application of a certain material directly onto the exhibit. The chemical and physical processing applied to the fingerprint potentially degrades or prevents further forensic testing on the same evidence sample. Many existing methods also have deleterious side effects. We introduce a method to detect and extract latent fingerprint images without applying any powder or chemicals on the object. Our method is based on the optical phenomena of polarization and specular reflection together with the physiology of fingerprint formation. The recovered image quality is comparable to existing methods. In some cases, such as the sticky side of tape, our method shows unique advantages.

  20. Hidden Markov latent variable models with multivariate longitudinal data.

    Science.gov (United States)

    Song, Xinyuan; Xia, Yemao; Zhu, Hongtu

    2017-03-01

    Cocaine addiction is chronic and persistent, and has become a major social and health problem in many countries. Existing studies have shown that cocaine addicts often undergo episodic periods of addiction to, moderate dependence on, or swearing off cocaine. Given its reversible feature, cocaine use can be formulated as a stochastic process that transits from one state to another, while the impacts of various factors, such as treatment received and individuals' psychological problems on cocaine use, may vary across states. This article develops a hidden Markov latent variable model to study multivariate longitudinal data concerning cocaine use from a California Civil Addict Program. The proposed model generalizes conventional latent variable models to allow bidirectional transition between cocaine-addiction states and conventional hidden Markov models to allow latent variables and their dynamic interrelationship. We develop a maximum-likelihood approach, along with a Monte Carlo expectation conditional maximization (MCECM) algorithm, to conduct parameter estimation. The asymptotic properties of the parameter estimates and statistics for testing the heterogeneity of model parameters are investigated. The finite sample performance of the proposed methodology is demonstrated by simulation studies. The application to cocaine use study provides insights into the prevention of cocaine use. © 2016, The International Biometric Society.

  1. [Latent Class Analysis of Gambling Activities among Korean Adolescents].

    Science.gov (United States)

    Kang, Kyonghwa; Kim, Hyeongsu; Park, Ae Ran; Kim, Hee Young; Lee, Kunsei

    2018-04-01

    The aim of this study is to identify the types of gambling among adolescents and provide basic prevention information regarding adolescents' gambling problems. Secondary data from representative national survey on 2015 Youth Gambling Problems of Korea Center on Gambling Problems were used. Using latent class analysis (LCA), 13 gambling types such as offline and online games of 14,011 adolescents were classified, and gambling experiences and characteristics were analyzed. The subgroups of adolescent gambling were identified as four latent classes: a rare group (84.5% of the sample), a risk group (1.0%), an offline group (11.9%), and an expanded group (2.6%). The types and characteristics of gambling among the latent classes differed. In the risk group, adolescents participated in online illegal sports betting and internet casino, and gambling time, gambling expenses, and the number of gambling types were higher than other groups. Gambling frequently occur among adolescent, and the subtypes of gambling did not reveal homogeneous characteristics. In order to prevent adolescent gambling problems, it is a necessary to develop tailored prevention intervention in the nursing field, which is appropriate to the characteristics of adolescent gambling group and can help with early identification. © 2018 Korean Society of Nursing Science.

  2. Broad CTL response is required to clear latent HIV-1 due to dominance of escape mutations

    Science.gov (United States)

    Deng, Kai; Pertea, Mihaela; Rongvaux, Anthony; Wang, Leyao; Durand, Christine M.; Ghiaur, Gabriel; Lai, Jun; McHugh, Holly L.; Hao, Haiping; Zhang, Hao; Margolick, Joseph B.; Gurer, Cagan; Murphy, Andrew J.; Valenzuela, David M.; Yancopoulos, George D.; Deeks, Steven G.; Strowig, Till; Kumar, Priti; Siliciano, Janet D.; Salzberg, Steven L.; Flavell, Richard A.; Shan, Liang; Siliciano, Robert F.

    2015-01-01

    Despite antiretroviral therapy (ART), HIV-1 persists in a stable latent reservoir1, 2, primarily in resting memory CD4+ T cells3, 4. This reservoir presents a major barrier to the cure of HIV-1 infection. To purge the reservoir, pharmacological reactivation of latent HIV-1 has been proposed5 and tested both in vitro and in vivo6–8. A key remaining question is whether virus-specific immune mechanisms including cytolytic T lymphocytes (CTL) can clear infected cells in ART-treated patients after latency is reversed. Here we show that there is a striking all or none pattern for CTL escape mutations in HIV-1 Gag epitopes. Unless ART is started early, the vast majority (>98%) of latent viruses carry CTL escape mutations that render infected cells insensitive to CTLs directed at common epitopes. To solve this problem, we identified CTLs that could recognize epitopes from latent HIV-1 that were unmutated in every chronically infected patient tested. Upon stimulation, these CTLs eliminated target cells infected with autologous virus derived from the latent reservoir, both in vitro and in patient-derived humanized mice. The predominance of CTL-resistant viruses in the latent reservoir poses a major challenge to viral eradication. Our results demonstrate that chronically infected patients retain a broad spectrum viral-specific CTL response and that appropriate boosting of this response may be required for the elimination of the latent reservoir. PMID:25561180

  3. Cost-effectiveness of post-landing latent tuberculosis infection control strategies in new migrants to Canada.

    Science.gov (United States)

    Campbell, Jonathon R; Johnston, James C; Sadatsafavi, Mohsen; Cook, Victoria J; Elwood, R Kevin; Marra, Fawziah

    2017-01-01

    The majority of tuberculosis in migrants to Canada occurs due to reactivation of latent TB infection. Risk of tuberculosis in those with latent tuberculosis infection can be significantly reduced with treatment. Presently, only 2.4% of new migrants are flagged for post-landing surveillance, which may include latent tuberculosis infection screening; no other migrants receive routine latent tuberculosis infection screening. To aid in reducing the tuberculosis burden in new migrants to Canada, we determined the cost-effectiveness of using different latent tuberculosis infection interventions in migrants under post-arrival surveillance and in all new migrants. A discrete event simulation model was developed that focused on a Canadian permanent resident cohort after arrival in Canada, utilizing a ten-year time horizon, healthcare system perspective, and 1.5% discount rate. Latent tuberculosis infection interventions were evaluated in the population under surveillance (N = 6100) and the total cohort (N = 260,600). In all evaluations, six different screening and treatment combinations were compared to the base case of tuberculin skin test screening followed by isoniazid treatment only in the population under surveillance. Quality adjusted life years, incident tuberculosis cases, and costs were recorded for each intervention and incremental cost-effectiveness ratios were calculated in relation to the base case. In the population under surveillance (N = 6100), using an interferon-gamma release assay followed by rifampin was dominant compared to the base case, preventing 4.90 cases of tuberculosis, a 4.9% reduction, adding 4.0 quality adjusted life years, and saving $353,013 over the ensuing ten-years. Latent tuberculosis infection screening in the total population (N = 260,600) was not cost-effective when compared to the base case, however could potentially prevent 21.8% of incident tuberculosis cases. Screening new migrants under surveillance with an interferon

  4. Ocorrência de DNA de herpesvírus bovino tipo 4 em gado Holstein argentino de Santiago del Estero, Argentina

    Directory of Open Access Journals (Sweden)

    Sandra Elizabeth Pérez

    2011-12-01

    Full Text Available O herpesvírus bovino tipo 4 (BoHV-4 é um gama-herpesvírus que foi isolado de animais aparentemente saudáveis e de gado com uma variedade de sinais clínicos. O papel patogênico do BoHV-4 ainda não está claro e não se sabe se o vírus age como um patógeno primário ou se facilita infecções secundárias. Depois de infecções naturais ou experimentais, BoHV-4 pode estabelecer latência, principalmente nas células dos linhagens de monócitos/macrófagos. O vírus latente pode ser reativado após o uso de glicocorticóides ou por fatores de estresse. Em 2007, o BoHV-4 foi isolado pela primeira vez na Argentina, a partir de amostras de abortos bovinos. No presente estudo, utilizou-se o isolamento viral, nested PCR e análise com endonucleases de restrição (REA para investigar a presença de BoHV4 em leucócitos de bovinos provenientes de um único rebanho de gado leiteiro com problemas reprodutivos. Neste trabalho, demonstramos que o genoma do BoHV-4 está presente nos leucócitos em uma elevada proporção (63,4% dos animais, provavelmente em um estado latente ou persistente. BoHV-4 foi isolado de uma de cada onze amostras de leucócitos no sangue periférico (PBL. Por REA nós demonstramos a existência de variações genômicas entre as estirpes circulantes deste rebanho particular. Além disso, todas as amostras de PBL avaliados neste estudo diferiram da estirpe protótipo Americano, DN 599. Em geral, este estudo demonstrou que o BoHV-4 está presente na fração leucocitária do gado leiteiro e que as estirpes virais presentes neste rebanho são geneticamente divergentes. Embora que BoHV-4 foi detectado em um rebanho com história de distúrbios reprodutivos, não é possível concluir que o vírus é o principal responsável por estas condições.

  5. Semi-supervised learning based probabilistic latent semantic analysis for automatic image annotation

    Institute of Scientific and Technical Information of China (English)

    Tian Dongping

    2017-01-01

    In recent years, multimedia annotation problem has been attracting significant research attention in multimedia and computer vision areas, especially for automatic image annotation, whose purpose is to provide an efficient and effective searching environment for users to query their images more easily.In this paper, a semi-supervised learning based probabilistic latent semantic analysis ( PL-SA) model for automatic image annotation is presenred.Since it' s often hard to obtain or create la-beled images in large quantities while unlabeled ones are easier to collect, a transductive support vector machine ( TSVM) is exploited to enhance the quality of the training image data.Then, differ-ent image features with different magnitudes will result in different performance for automatic image annotation.To this end, a Gaussian normalization method is utilized to normalize different features extracted from effective image regions segmented by the normalized cuts algorithm so as to reserve the intrinsic content of images as complete as possible.Finally, a PLSA model with asymmetric mo-dalities is constructed based on the expectation maximization( EM) algorithm to predict a candidate set of annotations with confidence scores.Extensive experiments on the general-purpose Corel5k dataset demonstrate that the proposed model can significantly improve performance of traditional PL-SA for the task of automatic image annotation.

  6. Ultra high temperature latent heat energy storage and thermophotovoltaic energy conversion

    OpenAIRE

    Datas Medina, Alejandro; Ramos Cabal, Alba; Martí Vega, Antonio; Cañizo Nadal, Carlos del; Luque López, Antonio

    2016-01-01

    A conceptual energy storage system design that utilizes ultra high temperature phase change materials is presented. In this system, the energy is stored in the form of latent heat and converted to electricity upon demand by TPV (thermophotovoltaic) cells. Silicon is considered in this study as PCM (phase change material) due to its extremely high latent heat (1800 J/g or 500 Wh/kg), melting point (1410 C), thermal conductivity (~25 W/mK), low cost (less than $2/kg or $4/kWh) and a...

  7. 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…

  8. The Latent Class Structure of Chinese Patients with Eating Disorders in Shanghai.

    Science.gov (United States)

    Zheng, Yuchen; Kang, Qing; Huang, Jiabin; Jiang, Wenhui; Liu, Qiang; Chen, Han; Fan, Qing; Wang, Zhen; Chen, Jue; Xiao, Zeping

    2017-08-25

    Eating disorder is culture related, and the clinical symptoms are different between eastern and western patients. So the validity of feeding and eating disorders in the upcoming ICD-11 guide for Chinese patients is unclear. To explore the latent class structure of Chinese patients with eating disorder and the cross-cultural validity of the eating disorder section of the new ICD-11 guide in China. A total of 379 patients with eating disorders at Shanghai Mental Health Center were evaluated using the EDI questionnaire and a questionnaire developed by researchers from 2010 to 2016. SPSS 20.0 was used to enter data and analyze demographic data, and Latent GOLD was employed to conduct latent profile analysis. According to the results of latent profile analysis, patients with eating disorder were divided into five classes: low-weight fasting class (23.1%), non-fat-phobic binge/purge class (21.54%), low-fat-phobic binge class (19.27%), fat-phobic binge class (19.27%), and non-fat-phobic low-weight class (16.76%). Among the clinical symptoms extracted, there were significant differences in Body Mass Index (BMI), binge eating behavior, self-induced vomiting, laxative use and fat-phobic opinion; while there was no significant difference in restrictive food intake. Based on the clinical symptoms, there are five latent classes in Chinese patients with eating disorder, which is in accordance with the diagnostic categories of feeding and eating disorder in ICD-11. However, further work is needed in improving the fat-phobic opinion of patients with eating disorder and clarifying the BMI standard of thinness in the Chinese population.

  9. Application of a latent class analysis to empirically define eating disorder phenotypes.

    Science.gov (United States)

    Keel, Pamela K; Fichter, Manfred; Quadflieg, Norbert; Bulik, Cynthia M; Baxter, Mark G; Thornton, Laura; Halmi, Katherine A; Kaplan, Allan S; Strober, Michael; Woodside, D Blake; Crow, Scott J; Mitchell, James E; Rotondo, Alessandro; Mauri, Mauro; Cassano, Giovanni; Treasure, Janet; Goldman, David; Berrettini, Wade H; Kaye, Walter H

    2004-02-01

    Diagnostic criteria for eating disorders influence how we recognize, research, and treat eating disorders, and empirically valid phenotypes are required for revealing their genetic bases. To empirically define eating disorder phenotypes. Data regarding eating disorder symptoms and features from 1179 individuals with clinically significant eating disorders were submitted to a latent class analysis. The resulting latent classes were compared on non-eating disorder variables in a series of validation analyses. Multinational, collaborative study with cases ascertained through diverse clinical settings (inpatient, outpatient, and community). Members of affected relative pairs recruited for participation in genetic studies of eating disorders in which probands met DSM-IV-TR criteria for anorexia nervosa (AN) or bulimia nervosa and had at least 1 biological relative with a clinically significant eating disorder. Main Outcome Measure Number and clinical characterization of latent classes. A 4-class solution provided the best fit. Latent class 1 (LC1) resembled restricting AN; LC2, AN and bulimia nervosa with the use of multiple methods of purging; LC3, restricting AN without obsessive-compulsive features; and LC4, bulimia nervosa with self-induced vomiting as the sole form of purging. Biological relatives were significantly likely to belong to the same latent class. Across validation analyses, LC2 demonstrated the highest levels of psychological disturbance, and LC3 demonstrated the lowest. The presence of obsessive-compulsive features differentiates among individuals with restricting AN. Similarly, the combination of low weight and multiple methods of purging distinguishes among individuals with binge eating and purging behaviors. These results support some of the distinctions drawn within the DSM-IV-TR among eating disorder subtypes, while introducing new features to define phenotypes.

  10. Resveratrol Reactivates Latent HIV through Increasing Histone Acetylation and Activating Heat Shock Factor 1.

    Science.gov (United States)

    Zeng, Xiaoyun; Pan, Xiaoyan; Xu, Xinfeng; Lin, Jian; Que, Fuchang; Tian, Yuanxin; Li, Lin; Liu, Shuwen

    2017-06-07

    The persistence of latent HIV reservoirs presents a significant challenge to viral eradication. Effective latency reversing agents (LRAs) based on "shock and kill" strategy are urgently needed. The natural phytoalexin resveratrol has been demonstrated to enhance HIV gene expression, although its mechanism remains unclear. In this study, we demonstrated that resveratrol was able to reactivate latent HIV without global T cell activation in vitro. Mode of action studies showed resveratrol-mediated reactivation from latency did not involve the activation of silent mating type information regulation 2 homologue 1 (SIRT1), which belonged to class-3 histone deacetylase (HDAC). However, latent HIV was reactivated by resveratrol mediated through increasing histone acetylation and activation of heat shock factor 1 (HSF1). Additionally, synergistic activation of the latent HIV reservoirs was observed under cotreatment with resveratrol and conventional LRAs. Collectively, this research reveals that resveratrol is a natural LRA and shows promise for HIV therapy.

  11. Natural Products from Antarctic Colonial Ascidians of the Genera <em>Aplidium> and <em>Synoicum>: Variability and Defensive Role

    Directory of Open Access Journals (Sweden)

    Conxita Avila

    2012-08-01

    Full Text Available Ascidians have developed multiple defensive strategies mostly related to physical, nutritional or chemical properties of the tunic. One of such is chemical defense based on secondary metabolites. We analyzed a series of colonial Antarctic ascidians from deep-water collections belonging to the genera <em>Aplidium> and <em>Synoicum> to evaluate the incidence of organic deterrents and their variability. The ether fractions from 15 samples including specimens of the species <em>A.> <em>falklandicum>, <em>A.> <em>fuegiense>, <em>A.> <em>meridianum>, <em>A.> <em>millari> and <em>S.> <em>adareanum> were subjected to feeding assays towards two relevant sympatric predators: the starfish <em>Odontaster> <em>validus>, and the amphipod <em>Cheirimedon> <em>femoratus>. All samples revealed repellency. Nonetheless, some colonies concentrated defensive chemicals in internal body-regions rather than in the tunic. Four ascidian-derived meroterpenoids, rossinones B and the three derivatives 2,3-epoxy-rossinone B, 3-epi-rossinone B, 5,6-epoxy-rossinone B, and the indole alkaloids meridianins A–G, along with other minoritary meridianin compounds were isolated from several samples. Some purified metabolites were tested in feeding assays exhibiting potent unpalatabilities, thus revealing their role in predation avoidance. Ascidian extracts and purified compound-fractions were further assessed in antibacterial tests against a marine Antarctic bacterium. Only the meridianins showed inhibition activity, demonstrating a multifunctional defensive role. According to their occurrence in nature and within our colonial specimens, the possible origin of both types of metabolites is discussed.

  12. Development of molecular tests for the detection of ILAR and latent viruses in fruit trees.

    Science.gov (United States)

    Roussel, S; Kummert, J; Dutrecq, O; Lepoivre, P; Jijakli, M H

    2004-01-01

    The detection throughout the year of latent and ILAR viruses in fruit tress by classical serological tests appear to be unreliable. We have developed RT-PCR tests for a reliable detection of latent and ILAR viruses in fruit trees. These assays were then simplified to allow the direct use of crude plant extracts instead of total RNA preparations, and the analyses of pooled samples. In this way, such RT-PCR protocols are suitable for a routine diagnosis of latent and ILAR viruses in fruit tree certification.

  13. A stable latent reservoir for HIV-1 in resting CD4+ T lymphocytes in infected children

    Science.gov (United States)

    Persaud, Deborah; Pierson, Theodore; Ruff, Christian; Finzi, Diana; Chadwick, Karen R.; Margolick, Joseph B.; Ruff, Andrea; Hutton, Nancy; Ray, Stuart; Siliciano, Robert F.

    2000-01-01

    HIV-1 persists in a latent state in resting CD4+ T lymphocytes of infected adults despite prolonged highly active antiretroviral therapy (HAART). To determine whether a latent reservoir for HIV-1 exists in infected children, we performed a quantitative viral culture assay on highly purified resting CD4+ T cells from 21 children with perinatally acquired infection. Replication-competent HIV-1 was recovered from all 18 children from whom sufficient cells were obtained. The frequency of latently infected resting CD4+ T cells directly correlated with plasma virus levels, suggesting that in children with ongoing viral replication, most latently infected cells are in the labile preintegration state of latency. However, in each of 7 children who had suppression of viral replication to undetectable levels for 1–3 years on HAART, latent replication-competent HIV-1 persisted with little decay, owing to a stable reservoir of infected cells in the postintegration stage of latency. Drug-resistance mutations generated by previous nonsuppressive regimens persisted in this compartment despite more than 1 year of fully suppressive HAART, rendering untenable the idea of recycling drugs that were part of failed regimens. Thus the latent reservoir for HIV-1 in resting CD4+ T cells will be a major obstacle to HIV-1 eradication in children. PMID:10749578

  14. Fumigant Antifungal Activity of Myrtaceae Essential Oils and Constituents from <em>Leptospermum petersoniiem> against Three <em>Aspergillus> Species

    Directory of Open Access Journals (Sweden)

    Il-Kwon Park

    2012-09-01

    Full Text Available Commercial plant essential oils obtained from 11 Myrtaceae plant species were tested for their fumigant antifungal activity against <em>Aspergillus ochraceusem>, <em>A. flavusem>, and <em>A. nigerem>. Essential oils extracted from<em> em>Leptospermum> <em>petersonii> at air concentrations of 56 × 10−3 mg/mL and 28 × 10−3 mg/mL completely inhibited the growth of the three <em>Aspergillus> species. However, at an air concentration of 14 × 10−3 mg/mL, inhibition rates of <em>L. petersoniiem> essential oils were reduced to 20.2% and 18.8% in the case of <em>A. flavusem> and <em>A. nigerem>, respectively. The other Myrtaceae essential oils (56 × 10−3 mg/mL only weakly inhibited the fungi or had no detectable affect. Gas chromatography-mass spectrometry analysis identified 16 compounds in <em>L. petersoniiem>> em>essential> em>oil.> em>The antifungal activity of the identified compounds was tested individually by using standard or synthesized compounds. Of these, neral and geranial inhibited growth by 100%, at an air concentration of 56 × 10−3 mg/mL, whereas the activity of citronellol was somewhat lover (80%. The other compounds exhibited only moderate or weak antifungal activity. The antifungal activities of blends of constituents identified in <em>L. petersoniiem> oil indicated that neral and geranial were the major contributors to the fumigant and antifungal activities.

  15. A Latent Class Regression Analysis of Men's Conformity to Masculine Norms and Psychological Distress

    Science.gov (United States)

    Wong, Y. Joel; Owen, Jesse; Shea, Munyi

    2012-01-01

    How are specific dimensions of masculinity related to psychological distress in specific groups of men? To address this question, the authors used latent class regression to assess the optimal number of latent classes that explained differential relationships between conformity to masculine norms and psychological distress in a racially diverse…

  16. Latent class analysis of the Yale-Brown Obsessive-Compulsive Scale symptoms in obsessive-compulsive disorder.

    Science.gov (United States)

    Delucchi, Kevin L; Katerberg, Hilga; Stewart, S Evelyn; Denys, Damiaan A J P; Lochner, Christine; Stack, Denise E; den Boer, Johan A; van Balkom, Anton J L M; Jenike, Michael A; Stein, Dan J; Cath, Danielle C; Mathews, Carol A

    2011-01-01

    Obsessive-compulsive disorder (OCD) is phenomenologically heterogeneous, and findings of underlying structure classification based on symptom grouping have been ambiguous to date. Variable-centered approaches, primarily factor analysis, have been used to identify homogeneous groups of symptoms; but person-centered latent methods have seen little use. This study was designed to uncover sets of homogeneous groupings within 1611 individuals with OCD based on symptoms. Latent class analysis models using 61 obsessive-compulsive symptoms collected from the Yale-Brown Obsessive-Compulsive Scale were fit. Relationships between latent class membership and treatment response, sex, symptom severity, and comorbid tic disorders were tested for relationship to class membership. Latent class analysis models of best fit yielded 3 classes. Classes differed only in frequency of symptom endorsement. Classes with higher symptom endorsement were associated with earlier age of onset, being male, higher Yale-Brown Obsessive-Compulsive Scale symptom severity scores, and comorbid tic disorders. There were no differences in treatment response between classes. These results provide support for the validity of a single underlying latent OCD construct, in addition to the distinct symptom factors identified previously via factor analyses. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. New approaches for examining associations with latent categorical variables: applications to substance abuse and aggression.

    Science.gov (United States)

    Feingold, Alan; Tiberio, Stacey S; Capaldi, Deborah M

    2014-03-01

    Assessments of substance use behaviors often include categorical variables that are frequently related to other measures using logistic regression or chi-square analysis. When the categorical variable is latent (e.g., extracted from a latent class analysis [LCA]), classification of observations is often used to create an observed nominal variable from the latent one for use in a subsequent analysis. However, recent simulation studies have found that this classical 3-step analysis championed by the pioneers of LCA produces underestimates of the associations of latent classes with other variables. Two preferable but underused alternatives for examining such linkages-each of which is most appropriate under certain conditions-are (a) 3-step analysis, which corrects the underestimation bias of the classical approach, and (b) 1-step analysis. The purpose of this article is to dissuade researchers from conducting classical 3-step analysis and to promote the use of the 2 newer approaches that are described and compared. In addition, the applications of these newer models-for use when the independent, the dependent, or both categorical variables are latent-are illustrated through substantive analyses relating classes of substance abusers to classes of intimate partner aggressors.

  18. Effect of acycloguanosine treatment of acute and latent herpes simplex infections in mice.

    Science.gov (United States)

    Field, H J; Bell, S E; Elion, G B; Nash, A A; Wildy, P

    1979-04-01

    Systemic treatment of mice with the nucleoside analog 9-(2-hydroxyethoxymethyl)guanine (acycloguanosine [aciclovir]) was found to be highly effective against acute type 1 herpes simplex virus infection of the pinna. The drug ablated clinical signs and reduced virus replication both in tissue local to the inoculation site and within the nervous system. Provided that moderate-sized virus inocula were used, acycloguanosine treatment reduced or prevented the establishment of a latent infection in the dorsal root ganglia relating to the sensory nerve supply of the ear. However, although it aborted artificially produced infections in dorsal root ganglia, acycloguanosine was found not to be effective against the latent infection once established. This finding strongly indicated that latent herpes simplex virus in mice can exist in a nonreplicating form.

  19. A Framework for Reproducible Latent Fingerprint Enhancements.

    Science.gov (United States)

    Carasso, Alfred S

    2014-01-01

    Photoshop processing of latent fingerprints is the preferred methodology among law enforcement forensic experts, but that appproach is not fully reproducible and may lead to questionable enhancements. Alternative, independent, fully reproducible enhancements, using IDL Histogram Equalization and IDL Adaptive Histogram Equalization, can produce better-defined ridge structures, along with considerable background information. Applying a systematic slow motion smoothing procedure to such IDL enhancements, based on the rapid FFT solution of a Lévy stable fractional diffusion equation, can attenuate background detail while preserving ridge information. The resulting smoothed latent print enhancements are comparable to, but distinct from, forensic Photoshop images suitable for input into automated fingerprint identification systems, (AFIS). In addition, this progressive smoothing procedure can be reexamined by displaying the suite of progressively smoother IDL images. That suite can be stored, providing an audit trail that allows monitoring for possible loss of useful information, in transit to the user-selected optimal image. Such independent and fully reproducible enhancements provide a valuable frame of reference that may be helpful in informing, complementing, and possibly validating the forensic Photoshop methodology.

  20. Latent heat of traffic moving from rest

    Science.gov (United States)

    Farzad Ahmadi, S.; Berrier, Austin S.; Doty, William M.; Greer, Pat G.; Habibi, Mohammad; Morgan, Hunter A.; Waterman, Josam H. C.; Abaid, Nicole; Boreyko, Jonathan B.

    2017-11-01

    Contrary to traditional thinking and driver intuition, here we show that there is no benefit to ground vehicles increasing their packing density at stoppages. By systematically controlling the packing density of vehicles queued at a traffic light on a Smart Road, drone footage revealed that the benefit of an initial increase in displacement for close-packed vehicles is completely offset by the lag time inherent to changing back into a ‘liquid phase’ when flow resumes. This lag is analogous to the thermodynamic concept of the latent heat of fusion, as the ‘temperature’ (kinetic energy) of the vehicles cannot increase until the traffic ‘melts’ into the liquid phase. These findings suggest that in situations where gridlock is not an issue, drivers should not decrease their spacing during stoppages in order to lessen the likelihood of collisions with no loss in flow efficiency. In contrast, motion capture experiments of a line of people walking from rest showed higher flow efficiency with increased packing densities, indicating that the importance of latent heat becomes trivial for slower moving systems.

  1. Lanthanide mixed ligand chelates for DNA profiling and latent fingerprint detection

    Science.gov (United States)

    Menzel, E. R.; Allred, Clay

    1997-02-01

    It is our aim to develop a universally applicable latent fingerprint detection method using lanthanide (rare-earth) complexes as a source of luminescence. Use of these lanthanide complexes offers advantages on several fronts, including benefits from large Stokes shifts, long luminescence lifetimes, narrow emissions, ability of sequential assembly of complexes, and chemical variability of the ligands. Proper exploitation of these advantages would lead to a latent fingerprint detection method superior to any currently available. These same characteristics also lend themselves to many of the problems associated with DNA processing in the forensic science context.

  2. Clinical Relevance of <em>CDH1em> and <em>CDH13em> DNA-Methylation in Serum of Cervical Cancer Patients

    Directory of Open Access Journals (Sweden)

    Günther K. Bonn

    2012-07-01

    Full Text Available This study was designed to investigate the DNA-methylation status of <em>E>-cadherin (<em>CDH1em> and <em>H>-cadherin (<em>CDH13em> in serum samples of cervical cancer patients and control patients with no malignant diseases and to evaluate the clinical utility of these markers. DNA-methylation status of <em>CDH1em> and <em>CDH13em> was analyzed by means of MethyLight-technology in serum samples from 49 cervical cancer patients and 40 patients with diseases other than cancer. To compare this methylation analysis with another technique, we analyzed the samples with a denaturing high performance liquid chromatography (DHPLC PCR-method. The specificity and sensitivity of <em>CDH1em> DNA-methylation measured by MethyLight was 75% and 55%, and for <em>CDH13em> DNA-methylation 95% and 10%. We identified a specificity of 92.5% and a sensitivity of only 27% for the <em>CDH1em> DHPLC-PCR analysis. Multivariate analysis showed that serum <em>CDH1em> methylation-positive patients had a 7.8-fold risk for death (95% CI: 2.2–27.7; <em>p> = 0.001 and a 92.8-fold risk for relapse (95% CI: 3.9–2207.1; <em>p> = 0.005. We concluded that the serological detection of <em>CDH1em> and <em>CDH13em> DNA-hypermethylation is not an ideal diagnostic tool due to low diagnostic specificity and sensitivity. However, it was validated that <em>CDH1em> methylation analysis in serum samples may be of potential use as a prognostic marker for cervical cancer patients.

  3. Age is associated with latent tuberculosis in nurses

    Directory of Open Access Journals (Sweden)

    Naesinee Chaiear

    2016-12-01

    Full Text Available Objective: To evaluate risk factors for developing latent tuberculosis (LTB in Thai nurses. Methods: A comparison study was conducted at Srinagarind Hospital, Khon Kaen, Thailand. Clinical factors were compared between persons with tuberculin conversion and those without tuberculin conversion identified by tuberculin skin test. Results: There were 173 eligible persons with the LTB (34.7%. There were five workplaces where participants worked regularly including the general ward, surgical ward, pediatric ward, medical ward and critical care ward. In a multivariate model, two factors were significantly associated with LTB including age and history of tuberculosis in colleagues. The adjusted odds ratio (95% confidence interval of both variables were 1.056 (1.004–1.104 and 0.202 (0.044– 0.941. Conclusions: Older age is associated with latent tuberculosis in nurses. LTB should be screened routinely and treated if diagnosed for nurses.

  4. When do latent class models overstate accuracy for diagnostic and other classifiers in the absence of a gold standard?

    Science.gov (United States)

    Spencer, Bruce D

    2012-06-01

    Latent class models are increasingly used to assess the accuracy of medical diagnostic tests and other classifications when no gold standard is available and the true state is unknown. When the latent class is treated as the true class, the latent class models provide measures of components of accuracy including specificity and sensitivity and their complements, type I and type II error rates. The error rates according to the latent class model differ from the true error rates, however, and empirical comparisons with a gold standard suggest the true error rates often are larger. We investigate conditions under which the true type I and type II error rates are larger than those provided by the latent class models. Results from Uebersax (1988, Psychological Bulletin 104, 405-416) are extended to accommodate random effects and covariates affecting the responses. The results are important for interpreting the results of latent class analyses. An error decomposition is presented that incorporates an error component from invalidity of the latent class model. © 2011, The International Biometric Society.

  5. The application of seasonal latent variable in forecasting electricity demand as an alternative method

    International Nuclear Information System (INIS)

    Sumer, Kutluk Kagan; Goktas, Ozlem; Hepsag, Aycan

    2009-01-01

    In this study, we used ARIMA, seasonal ARIMA (SARIMA) and alternatively the regression model with seasonal latent variable in forecasting electricity demand by using data that belongs to 'Kayseri and Vicinity Electricity Joint-Stock Company' over the 1997:1-2005:12 periods. This study tries to examine the advantages of forecasting with ARIMA, SARIMA methods and with the model has seasonal latent variable to each other. The results support that ARIMA and SARIMA models are unsuccessful in forecasting electricity demand. The regression model with seasonal latent variable used in this study gives more successful results than ARIMA and SARIMA models because also this model can consider seasonal fluctuations and structural breaks

  6. Notas sobre a versão em língua portuguesa da Escala de Bem-Estar Espiritual

    Directory of Open Access Journals (Sweden)

    Edson Zangiacomi Martinez

    2013-01-01

    Full Text Available OBJETIVO: Testar a Escala de Bem-Estar Espiritual (EBE, a versão em português da Spiritual Well-Being Scale (SWB, em uma amostra de universitários matriculados em cursos de pós-graduação da área da saúde, avaliando suas qualidades psicométricas. Entre os diferentes instrumentos que objetivam mensurar a espiritualidade, encontra-se a SWB, adaptada recentemente para a língua portuguesa. Os 20 itens desse instrumento originalmente dividem-se em duas dimensões: bem-estar religioso (BER e bem-estar existencial (BEE. MÉTODOS: A consistência interna dessas dimensões foi avaliada pelo coeficiente alfa de Cronbach. Foi utilizada análise fatorial com rotação oblíqua para avaliar a estrutura fatorial latente. Quatrocentos e quarenta e um indivíduos responderam ao instrumento. RESULTADOS: O instrumento apresenta satisfatória consistência interna, mas a análise fatorial sugere que os itens da dimensão BEE distribuem-se em dois fatores distintos, o que chama a atenção para a complexidade da estrutura fatorial do instrumento. CONCLUSÃO: A estrutura fatorial da escala EBE não é clara, e a presença de um efeito teto em grupos religiosos específicos pode prejudicar os estudos que buscam associações entre espiritualidade e aspectos relacionados à saúde. O uso do instrumento exige cautela, e posteriores estudos de revisão da escala são necessários.

  7. Latent tuberculosis in HIV positive, diagnosed by the M. tuberculosis specific interferon-gamma test

    DEFF Research Database (Denmark)

    Brock, Inger; Ruhwald, Morten; Lundgren, Bettina

    2006-01-01

    Although tuberculosis (TB) is a minor problem in Denmark, severe and complicated cases occur in HIV positive. Since the new M. tuberculosis specific test for latent TB, the QuantiFERON-TB In-Tube test (QFT-IT) became available the patients in our clinic have been screened for the presence of latent...

  8. Extraction of Dihydroquercetin<em> em>from <em>Larix gmeliniem>i> em>with Ultrasound-Assisted and Microwave-Assisted Alternant Digestion

    Directory of Open Access Journals (Sweden)

    Yuangang Zu

    2012-07-01

    Full Text Available An ultrasound and microwave assisted alternant extraction method (UMAE was applied for extracting dihydroquercetin (DHQ from <em>Larix gmeliniem>i> wood. This investigation was conducted using 60% ethanol as solvent, 1:12 solid to liquid ratio, and 3 h soaking time. The optimum treatment time was ultrasound 40 min, microwave 20 min, respectively, and the extraction was performed once. Under the optimized conditions, satisfactory extraction yield of the target analyte was obtained. Relative to ultrasound-assisted or microwave-assisted method, the proposed approach provides higher extraction yield. The effect of DHQ of different concentrations and synthetic antioxidants on oxidative stability in soy bean oil stored for 20 days at different temperatures (25 °C and 60 °C was compared. DHQ was more effective in restraining soy bean oil oxidation, and a dose-response relationship was observed. The antioxidant activity of DHQ was a little stronger than that of BHA and BHT. Soy bean oil supplemented with 0.08 mg/g DHQ exhibited favorable antioxidant effects and is preferable for effectively avoiding oxidation. The <em>L. gmeliniiem> wood samples before and after extraction were characterized by scanning electron microscopy. The results showed that the UMAE method is a simple and efficient technique for sample preparation.

  9. Recovery of latent fingerprints and DNA on human skin.

    Science.gov (United States)

    Färber, Doris; Seul, Andrea; Weisser, Hans-Joachim; Bohnert, Michael

    2010-11-01

    The project "Latent Fingerprints and DNA on Human Skin" was the first systematic research in Europe dealing with detection of fingerprints and DNA left by offenders on the skin of corpses. One thousand samples gave results that allow general statements on the materials and methods used. The tests were carried out according to a uniform trial structure. Fingerprints were deposited by natural donors on corpses. The latent fingerprints were treated with magnetic powder or black fingerprint powder. Afterward, they were lifted with silicone casting material (Isomark(®)) or gelatine foil. All lifts were swabbed to recover DNA. It was possible to visualize comparable and identifiable fingerprints on the skin of corpses (16%). In the same categories, magnetic powder (18.4%) yielded better results than black fingerprint powder (13.6%). The number of comparable and identifiable fingerprints decreased on the lifts (12.7%). Isomark(®) (14.9%) was the better lifting material in comparison with gelatine foil (10.1%). In one-third of the samples, DNA could be extracted from the powdered and lifted latents. Black fingerprint powder delivered the better result with a rate of 2.2% for full DNA profiles and profiles useful for exclusion in comparison with 1.8% for the magnetic powder traces. Isomark(®) (3.1%) yielded better results than gelatine foil (0.6%). © 2010 American Academy of Forensic Sciences.

  10. Latent cooling and microphysics effects in deep convection

    Science.gov (United States)

    Fernández-González, S.; Wang, P. K.; Gascón, E.; Valero, F.; Sánchez, J. L.

    2016-11-01

    Water phase changes within a storm are responsible for the enhancement of convection and therefore the elongation of its lifespan. Specifically, latent cooling absorbed during evaporation, melting and sublimation is considered the main cause of the intensification of downdrafts. In order to know more accurately the consequences of latent cooling caused by each of these processes (together with microphysical effects that they induce), four simulations were developed with the Wisconsin Dynamical and Microphysical Model (WISCDYMM): one with all the microphysical processes; other without sublimation; melting was suppressed in the third simulation; and evaporation was disabled in the fourth. The results show that sublimation cooling is not essential to maintain the vertical currents of the storm. This is demonstrated by the fact that in the simulation without sublimation, maximum updrafts are in the same range as in the control simulation, and the storm lifespan is similar or even longer. However, melting was of vital importance. The storm in the simulation without melting dissipated prematurely, demonstrating that melting is indispensable to the enhancement of downdrafts below the freezing level and for avoiding the collapse of low level updrafts. Perhaps the most important finding is the crucial influence of evaporative cooling above the freezing level that maintains and enhances mid-level downdrafts in the storm. It is believed that this latent cooling comes from the evaporation of supercooled liquid water connected with the Bergeron-Findeisen process. Therefore, besides its influence at low levels (which was already well known), this evaporative cooling is essential to strengthen mid-level downdrafts and ultimately achieve a quasi-steady state.

  11. Managerial performance and cost efficiency of Japanese local public hospitals: a latent class stochastic frontier model.

    Science.gov (United States)

    Besstremyannaya, Galina

    2011-09-01

    The paper explores the link between managerial performance and cost efficiency of 617 Japanese general local public hospitals in 1999-2007. Treating managerial performance as unobservable heterogeneity, the paper employs a panel data stochastic cost frontier model with latent classes. Financial parameters associated with better managerial performance are found to be positively significant in explaining the probability of belonging to the more efficient latent class. The analysis of latent class membership was consistent with the conjecture that unobservable technological heterogeneity reflected in the existence of the latent classes is related to managerial performance. The findings may support the cause for raising efficiency of Japanese local public hospitals by enhancing the quality of management. Copyright © 2011 John Wiley & Sons, Ltd.

  12. How <em>Varroa> Parasitism Affects the Immunological and Nutritional Status of the Honey Bee, <em>Apis melliferaem>

    Directory of Open Access Journals (Sweden)

    Katherine A. Aronstein

    2012-06-01

    Full Text Available We investigated the effect of the parasitic mite <em>Varroa destructorem> on the immunological and nutritional condition of honey bees, <em>Apis melliferaem>, from the perspective of the individual bee and the colony. Pupae, newly-emerged adults and foraging adults were sampled from honey bee colonies at one site in S. Texas, USA. <em>Varroa>‑infested bees displayed elevated titer of Deformed Wing Virus (DWV, suggestive of depressed capacity to limit viral replication. Expression of genes coding three anti-microbial peptides (<em>defensin1, abaecin, hymenoptaecinem> was either not significantly different between <em>Varroa>-infested and uninfested bees or was significantly elevated in <em>Varroa>-infested bees, varying with sampling date and bee developmental age. The effect of <em>Varroa> on nutritional indices of the bees was complex, with protein, triglyceride, glycogen and sugar levels strongly influenced by life-stage of the bee and individual colony. Protein content was depressed and free amino acid content elevated in <em>Varroa>-infested pupae, suggesting that protein synthesis, and consequently growth, may be limited in these insects. No simple relationship between the values of nutritional and immune-related indices was observed, and colony-scale effects were indicated by the reduced weight of pupae in colonies with high <em>Varroa> abundance, irrespective of whether the individual pupa bore <em>Varroa>.

  13. Upper atmosphere tidal oscillations due to latent heat release in the tropical troposphere

    Directory of Open Access Journals (Sweden)

    J. M. Forbes

    1997-09-01

    Full Text Available Latent heat release associated with tropical deep convective activity is investigated as a source for migrating (sun-synchronous diurnal and semidiurnal tidal oscillations in the 80–150-km height region. Satellite-based cloud brightness temperature measurements made between 1988 and 1994 and averaged into 3-h bins are used to determine the annual- and longitude-average local-time distribution of rainfall rate, and hence latent heating, between ±40° latitude. Regional average rainfall rates are shown to be in good agreement with climatological values derived from surface rain gauge data. A global linearized wave model is used to estimate the corresponding atmospheric perturbations in the mesosphere/lower thermosphere (80–150 km resulting from upward-propagating tidal components excited by the latent heating. The annual-average migrating diurnal and semidiurnal components achieve velocity and temperature amplitudes of order 10–20 m s–1 and 5–10 K, respectively, which represent substantial contributions to the dynamics of the region. The latent heat forcing also shifts the phase (local solar time of maximum of the semidiurnal surface pressure oscillation from 0912 to 0936 h, much closer to the observed value of 0944 h.

  14. Detection of latent prints by Raman imaging

    Science.gov (United States)

    Lewis, Linda Anne [Andersonville, TN; Connatser, Raynella Magdalene [Knoxville, TN; Lewis, Sr., Samuel Arthur

    2011-01-11

    The present invention relates to a method for detecting a print on a surface, the method comprising: (a) contacting the print with a Raman surface-enhancing agent to produce a Raman-enhanced print; and (b) detecting the Raman-enhanced print using a Raman spectroscopic method. The invention is particularly directed to the imaging of latent fingerprints.

  15. Proliferation of latently infected CD4+ T cells carrying replication-competent HIV-1: Potential role in latent reservoir dynamics

    Science.gov (United States)

    Hosmane, Nina N.; Kwon, Kyungyoon J.; Bruner, Katherine M.; Capoferri, Adam A.; Rosenbloom, Daniel I.S.; Keele, Brandon F.; Ho, Ya-Chi

    2017-01-01

    A latent reservoir for HIV-1 in resting CD4+ T lymphocytes precludes cure. Mechanisms underlying reservoir stability are unclear. Recent studies suggest an unexpected degree of infected cell proliferation in vivo. T cell activation drives proliferation but also reverses latency, resulting in productive infection that generally leads to cell death. In this study, we show that latently infected cells can proliferate in response to mitogens without producing virus, generating progeny cells that can release infectious virus. Thus, assays relying on one round of activation underestimate reservoir size. Sequencing of independent clonal isolates of replication-competent virus revealed that 57% had env sequences identical to other isolates from the same patient. Identity was confirmed by full-genome sequencing and was not attributable to limited viral diversity. Phylogenetic and statistical analysis suggested that identical sequences arose from in vivo proliferation of infected cells, rather than infection of multiple cells by a dominant viral species. The possibility that much of the reservoir arises by cell proliferation presents challenges to cure. PMID:28341641

  16. Proliferation of latently infected CD4+ T cells carrying replication-competent HIV-1: Potential role in latent reservoir dynamics.

    Science.gov (United States)

    Hosmane, Nina N; Kwon, Kyungyoon J; Bruner, Katherine M; Capoferri, Adam A; Beg, Subul; Rosenbloom, Daniel I S; Keele, Brandon F; Ho, Ya-Chi; Siliciano, Janet D; Siliciano, Robert F

    2017-04-03

    A latent reservoir for HIV-1 in resting CD4 + T lymphocytes precludes cure. Mechanisms underlying reservoir stability are unclear. Recent studies suggest an unexpected degree of infected cell proliferation in vivo. T cell activation drives proliferation but also reverses latency, resulting in productive infection that generally leads to cell death. In this study, we show that latently infected cells can proliferate in response to mitogens without producing virus, generating progeny cells that can release infectious virus. Thus, assays relying on one round of activation underestimate reservoir size. Sequencing of independent clonal isolates of replication-competent virus revealed that 57% had env sequences identical to other isolates from the same patient. Identity was confirmed by full-genome sequencing and was not attributable to limited viral diversity. Phylogenetic and statistical analysis suggested that identical sequences arose from in vivo proliferation of infected cells, rather than infection of multiple cells by a dominant viral species. The possibility that much of the reservoir arises by cell proliferation presents challenges to cure. © 2017 Hosmane et al.

  17. Longitudinal mixed-effects models for latent cognitive function

    NARCIS (Netherlands)

    van den Hout, Ardo; Fox, Gerardus J.A.; Muniz-Terrera, Graciela

    2015-01-01

    A mixed-effects regression model with a bent-cable change-point predictor is formulated to describe potential decline of cognitive function over time in the older population. For the individual trajectories, cognitive function is considered to be a latent variable measured through an item response

  18. Evaluation of AFIS-Ranked latent fingerprint matched templates

    NARCIS (Netherlands)

    Krish, Ram P.; Fierrez, Julian; Ramos, Daniel; Veldhuis, Raymond N.J.; 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

  19. When Factorization Meets Heterogeneous Latent Topics:An Interpretable Cross-Site Recommendation Framework

    Institute of Scientific and Technical Information of China (English)

    辛欣; 林钦佑; 魏骁驰; 黄河燕

    2015-01-01

    Data sparsity is a well-known challenge in recommender systems. Previous studies alleviate this problem by incorporating the information within the corresponding social media site. In this paper, we solve this challenge by exploring cross-site information. Specifically, we examine: 1) how to effectively and efficiently utilize cross-site ratings and content features to improve recommendation performance and 2) how to make the recommendation interpretable by utilizing content features. We propose a joint model of matrix factorization and latent topic analysis. Heterogeneous content features are modeled by multiple kinds of latent topics. In addition, the combination of matrix factorization and latent topics makes the recommendation result interpretable. Therefore, the above two issues are simultaneously solved. Through a real-world dataset, where user behaviors in three social media sites are collected, we demonstrate that the proposed model is effective in improving recommendation performance and interpreting the rationale of ratings.

  20. Extending dynamic segmentation with lead generation : A latent class Markov analysis of financial product portfolios

    NARCIS (Netherlands)

    Paas, L.J.; Bijmolt, T.H.A.; Vermunt, J.K.

    2004-01-01

    A recent development in marketing research concerns the incorporation of dynamics in consumer segmentation.This paper extends the latent class Markov model, a suitable technique for conducting dynamic segmentation, in order to facilitate lead generation.We demonstrate the application of the latent

  1. Trophic systems and chorology: data from shrews, moles and voles of Italy preyed by the barn owl / Sistemi trofici e corologia: dati su <em>Soricidae>, <em>Talpidae> ed <em>Arvicolidae> d'Italia predati da <em>Tyto albaem> (Scopoli 1769

    Directory of Open Access Journals (Sweden)

    Longino Contoli

    1986-12-01

    Full Text Available Abstract In small Mammals biogeography, available data are up to now by far too scanty for elucidate the distribution of a lot of taxa, especially with regard to the absence from a given area. In this respect, standardized quantitative sampling techniques, like Owl pellets analysis can enable not only to enhance faunistic knowledges, but also to estimate the actual absence probability of a given taxon "m", lacking from the diet of an individual raptor. For the last purpose, the relevant frequencies of "m" in the other ecologically similar sites of the same raptor species diets are averaged ($f_m$ : the relevant standard error (multiplicated by a coefficient, according to the desired degree of accuracy, in relation of the integral of probabilities subtracted ($overline{F}_m - a E$: then, the probability that a single specimen is not pertaining to "m" is obtained ($P_0 = 1 - F_m + a E$; lastly, the desiderate accuracy probability ($P_d$ is chosen. Now, "$N_d$" (the number of individuals of all prey species in a single site needed for obtain, with the desired probability, a specimen at least of "m" is obtained through $$N = frac{ln P_d}{ln P_0}$$ Obviously, every site-diet with more than "N" preyed individuals and without any "i" specimen is considered to be lacking of such taxon. A "usefulness index" for the above purposes is outlined and checked about three raptors. Some exanples about usefulness of the Owl pellet analysis method in biogeography are given, concerning <em>Tyto albaem> diets in peninsular Italy about: - <em>Sorex minutusem>, lacking in some quite insulated areas; - <em>Sorex araneusem> (sensu stricto, after GRAF et al., 1979, present also in lowland areas in Emilia-Romagna; - <em>Crocidura suaveolensem> and - <em>Suncus etruscusem>, present also in the southermost part of Calabria (Reggio province; - <em>Talpa caecaem>, present also in the Antiapennines of Latium (Cimini mounts; - <em>Talpa romanaem

  2. Space Flight-Induced Reactivation of Latent Epstein-Barr Virus

    Science.gov (United States)

    Stowe, Raymond P.; Barrett, Alan D. T.; Pierson, Duane L.

    2001-01-01

    Reactivation of latent Epstein-Barr virus (EBV) may be an important threat to crew health during extended space missions. Decreased cellular immune function has been reported both during and after space flight. Preliminary studies have demonstrated increased EBV shedding in saliva as well as increased antibody titers to EBV lytic proteins. We hypothesize that the combined effects of microgravity along with associated physical and psychological stress will decrease EBV-specific T-cell immunity and reactivate latent EBV in infected B-lymphocytes. If increased virus production and clonal expansion of infected B-lymphocytes are detected, then pharmacological measures can be developed and instituted prior to onset of overt clinical disease. More importantly, we will begin to understand the basic mechanisms involved in stress-induced reactivation of EBV in circulating B-lymphocytes.

  3. Transcriptional Reprogramming during Effector-to-Memory Transition Renders CD4+ T Cells Permissive for Latent HIV-1 Infection.

    Science.gov (United States)

    Shan, Liang; Deng, Kai; Gao, Hongbo; Xing, Sifei; Capoferri, Adam A; Durand, Christine M; Rabi, S Alireza; Laird, Gregory M; Kim, Michelle; Hosmane, Nina N; Yang, Hung-Chih; Zhang, Hao; Margolick, Joseph B; Li, Linghua; Cai, Weiping; Ke, Ruian; Flavell, Richard A; Siliciano, Janet D; Siliciano, Robert F

    2017-10-17

    The latent reservoir for HIV-1 in resting memory CD4 + T cells is the major barrier to curing HIV-1 infection. Studies of HIV-1 latency have focused on regulation of viral gene expression in cells in which latent infection is established. However, it remains unclear how infection initially becomes latent. Here we described a unique set of properties of CD4 + T cells undergoing effector-to-memory transition including temporary upregulation of CCR5 expression and rapid downregulation of cellular gene transcription. These cells allowed completion of steps in the HIV-1 life cycle through integration but suppressed HIV-1 gene transcription, thus allowing the establishment of latency. CD4 + T cells in this stage were substantially more permissive for HIV-1 latent infection than other CD4 + T cells. Establishment of latent HIV-1 infection in CD4 + T could be inhibited by viral-specific CD8 + T cells, a result with implications for elimination of latent HIV-1 infection by T cell-based vaccines. Copyright © 2017. Published by Elsevier Inc.

  4. Effect of Acycloguanosine Treatment on Acute and Latent Herpes Simplex Infections in Mice

    Science.gov (United States)

    Field, Hugh J.; Bell, Susanne E.; Elion, Gertrude B.; Nash, Anthony A.; Wildy, Peter

    1979-01-01

    Systemic treatment of mice with the nucleoside analog 9-(2-hydroxyethoxymethyl)guanine (acycloguanosine [aciclovir]) was found to be highly effective against acute type 1 herpes simplex virus infection of the pinna. The drug ablated clinical signs and reduced virus replication both in tissue local to the inoculation site and within the nervous system. Provided that moderate-sized virus inocula were used, acycloguanosine treatment reduced or prevented the establishment of a latent infection in the dorsal root ganglia relating to the sensory nerve supply of the ear. However, although it aborted artificially produced infections in dorsal root ganglia, acycloguanosine was found not to be effective against the latent infection once established. This finding strongly indicated that latent herpes simplex virus in mice can exist in a nonreplicating form. PMID:464587

  5. Automatic sleep classification using a data-driven topic model reveals latent sleep states

    DEFF Research Database (Denmark)

    Koch, Henriette; Christensen, Julie Anja Engelhard; Frandsen, Rune

    2014-01-01

    Latent Dirichlet Allocation. Model application was tested on control subjects and patients with periodic leg movements (PLM) representing a non-neurodegenerative group, and patients with idiopathic REM sleep behavior disorder (iRBD) and Parkinson's Disease (PD) representing a neurodegenerative group......Background: The golden standard for sleep classification uses manual scoring of polysomnography despite points of criticism such as oversimplification, low inter-rater reliability and the standard being designed on young and healthy subjects. New method: To meet the criticism and reveal the latent...... sleep states, this study developed a general and automatic sleep classifier using a data-driven approach. Spectral EEG and EOG measures and eye correlation in 1 s windows were calculated and each sleep epoch was expressed as a mixture of probabilities of latent sleep states by using the topic model...

  6. Failure of PCR to Detect Treponema pallidum ssp. pertenue DNA in Blood in Latent Yaws.

    Directory of Open Access Journals (Sweden)

    Michael Marks

    Full Text Available Yaws, caused by Treponema pallidum ssp. pertenue, is a neglected tropical disease closely related to venereal syphilis and is targeted for eradication by 2020. Latent yaws represents a diagnostic challenge, and current tools cannot adequately distinguish between individuals with true latent infection and individuals who are serofast following successful treatment. PCR on blood has previously been shown to detect T. pallidum DNA in patients with syphilis, suggesting that this approach may be of value in yaws. We performed real-time PCR for Treponema pallidum ssp. pertenue on blood samples from 140 children with positive T. pallidum Particle Agglutination (TPPA and Rapid Plasma Reagin (RPR tests and 7 controls (negative serology, all collected as part of a prospective study of yaws in the Solomon Islands. All samples were also tested by a nested PCR for T. pallidum. 12 patients had clinical evidence of active yaws whilst 128 were considered to have latent yaws. 43 children had high titre rapid plasma reagins (RPRs of ≥1:32. PCR testing with both assays gave negative results in all cases. It is possible that the failure to detect T. pallidum ssp. pertenue in blood reflects lower loads of organism in latent yaws compared to those in latent infection with T. pallidum ssp. pertenue, and/or a lower propensity for haematogenous dissemination in yaws than in syphilis. As the goal of the yaws control programme is eradication, a tool that can differentiate true latent infection from individuals who are serofast would be of value; however, PCR of blood is not that tool.

  7. Failure of PCR to Detect Treponema pallidum ssp. pertenue DNA in Blood in Latent Yaws.

    Science.gov (United States)

    Marks, Michael; Katz, Samantha; Chi, Kai-Hua; Vahi, Ventis; Sun, Yongcheng; Mabey, David C; Solomon, Anthony W; Chen, Cheng Y; Pillay, Allan

    2015-01-01

    Yaws, caused by Treponema pallidum ssp. pertenue, is a neglected tropical disease closely related to venereal syphilis and is targeted for eradication by 2020. Latent yaws represents a diagnostic challenge, and current tools cannot adequately distinguish between individuals with true latent infection and individuals who are serofast following successful treatment. PCR on blood has previously been shown to detect T. pallidum DNA in patients with syphilis, suggesting that this approach may be of value in yaws. We performed real-time PCR for Treponema pallidum ssp. pertenue on blood samples from 140 children with positive T. pallidum Particle Agglutination (TPPA) and Rapid Plasma Reagin (RPR) tests and 7 controls (negative serology), all collected as part of a prospective study of yaws in the Solomon Islands. All samples were also tested by a nested PCR for T. pallidum. 12 patients had clinical evidence of active yaws whilst 128 were considered to have latent yaws. 43 children had high titre rapid plasma reagins (RPRs) of ≥1:32. PCR testing with both assays gave negative results in all cases. It is possible that the failure to detect T. pallidum ssp. pertenue in blood reflects lower loads of organism in latent yaws compared to those in latent infection with T. pallidum ssp. pertenue, and/or a lower propensity for haematogenous dissemination in yaws than in syphilis. As the goal of the yaws control programme is eradication, a tool that can differentiate true latent infection from individuals who are serofast would be of value; however, PCR of blood is not that tool.

  8. The epigenetic landscape of latent Kaposi sarcoma-associated herpesvirus genomes.

    Directory of Open Access Journals (Sweden)

    Thomas Günther

    Full Text Available Herpesvirus latency is generally thought to be governed by epigenetic modifications, but the dynamics of viral chromatin at early timepoints of latent infection are poorly understood. Here, we report a comprehensive spatial and temporal analysis of DNA methylation and histone modifications during latent infection with Kaposi Sarcoma-associated herpesvirus (KSHV, the etiologic agent of Kaposi Sarcoma and primary effusion lymphoma (PEL. By use of high resolution tiling microarrays in conjunction with immunoprecipitation of methylated DNA (MeDIP or modified histones (chromatin IP, ChIP, our study revealed highly distinct landscapes of epigenetic modifications associated with latent KSHV infection in several tumor-derived cell lines as well as de novo infected endothelial cells. We find that KSHV genomes are subject to profound methylation at CpG dinucleotides, leading to the establishment of characteristic global DNA methylation patterns. However, such patterns evolve slowly and thus are unlikely to control early latency. In contrast, we observed that latency-specific histone modification patterns were rapidly established upon a de novo infection. Our analysis furthermore demonstrates that such patterns are not characterized by the absence of activating histone modifications, as H3K9/K14-ac and H3K4-me3 marks were prominently detected at several loci, including the promoter of the lytic cycle transactivator Rta. While these regions were furthermore largely devoid of the constitutive heterochromatin marker H3K9-me3, we observed rapid and widespread deposition of H3K27-me3 across latent KSHV genomes, a bivalent modification which is able to repress transcription in spite of the simultaneous presence of activating marks. Our findings suggest that the modification patterns identified here induce a poised state of repression during viral latency, which can be rapidly reversed once the lytic cycle is induced.

  9. High-temperature thermocline TES combining sensible and latent heat - CFD modeling and experimental validation

    Science.gov (United States)

    Zavattoni, Simone A.; Geissbühler, Lukas; Barbato, Maurizio C.; Zanganeh, Giw; Haselbacher, Andreas; Steinfeld, Aldo

    2017-06-01

    The concept of combined sensible/latent heat thermal energy storage (TES) has been exploited to mitigate an intrinsic thermocline TES systems drawback of heat transfer fluid outflow temperature reduction during discharging. In this study, the combined sensible/latent TES prototype under investigation is constituted by a packed bed of rocks and a small amount of encapsulated phase change material (AlSi12) as sensible heat and latent heat sections respectively. The thermo-fluid dynamics behavior of the combined TES prototype was analyzed by means of a computational fluid dynamics approach. Due to the small value of the characteristic vessel-to-particles diameter ratio, the effect of radial void-fraction variation, also known as channeling, was accounted for. Both the sensible and the latent heat sections of the storage were modeled as porous media under the assumption of local thermal non-equilibrium (LTNE). The commercial code ANSYS Fluent 15.0 was used to solve the model's constitutive conservation and transport equations obtaining a fairly good agreement with reference experimental measurements.

  10. Prognostic factors for tuberculosis development in children with latent tuberculous infection

    Directory of Open Access Journals (Sweden)

    N. V. Korneva

    2016-01-01

    Full Text Available Goal of the study: to detect specific immune response in children with latent tuberculous infection and define factors to forecast the development of the active disease in this group.Materials and methods. The changes in clinical, X-ray and immunological data were analyzed in 127 children when latent tuberculous infection was diagnosed and after 12 months of follow-up. The number of immunological tests was done for evaluation of humoral and cellular immunity in those suffering from latent tuberculous infection and active disease.Results. The obtained results showed high negative prognostic relevance of exposure to tuberculosis, concurrent disease, refusal to have preventive treatment and low efficiency of short-course preventive treatment, specific features of humoral and cellular immunity were defined which could be used as additional forecasting criteria for active tuberculosis development in children with latent tuberculous infection. 

  11. Reactivation of latent HIV-1 by new semi-synthetic ingenol esters

    Energy Technology Data Exchange (ETDEWEB)

    Pandeló José, Diego [Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902 (Brazil); Bartholomeeusen, Koen [Department of Medicine, Microbiology and Immunology, University of California at San Francisco, San Francisco, CA 94143-0703 (United States); Delveccio da Cunha, Rodrigo; Abreu, Celina Monteiro [Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902 (Brazil); Glinski, Jan [PlantaAnalytica LLC, Danbury, CT 06810 (United States); Barbizan Ferreira da Costa, Thais; Bacchi Rabay, Ana Flávia Mello; Pianowski Filho, Luiz Francisco [Kyolab Laboratories, Valinhos, São Paulo 13273-105 (Brazil); Dudycz, Lech W. [Lex Company Research Laboratories, Shirley 01464, MA (United States); Ranga, Udaykumar [Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru 560064 (India); Peterlin, Boris Matija [Department of Medicine, Microbiology and Immunology, University of California at San Francisco, San Francisco, CA 94143-0703 (United States); Pianowski, Luiz Francisco [Kyolab Laboratories, Valinhos, São Paulo 13273-105 (Brazil); Tanuri, Amilcar [Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902 (Brazil); Aguiar, Renato Santana, E-mail: santana@biologia.ufrj.br [Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902 (Brazil)

    2014-08-15

    The ability of HIV to establish long-lived latent infection is mainly due to transcriptional silencing of viral genome in resting memory T lymphocytes. Here, we show that new semi-synthetic ingenol esters reactivate latent HIV reservoirs. Amongst the tested compounds, 3-caproyl-ingenol (ING B) was more potent in reactivating latent HIV than known activators such as SAHA, ingenol 3,20-dibenzoate, TNF-α, PMA and HMBA. ING B activated PKC isoforms followed by NF-κB nuclear translocation. As virus reactivation is dependent on intact NF-κB binding sites in the LTR promoter region ING B, we have shown that. ING B was able to reactivate virus transcription in primary HIV-infected resting cells up to 12 fold and up to 25 fold in combination with SAHA. Additionally, ING B promoted up-regulation of P-TEFb subunits CDK9/Cyclin T1. The role of ING B on promoting both transcription initiation and elongation makes this compound a strong candidate for an anti-HIV latency drug combined with suppressive HAART. - Highlights: • 3-caproyl-ingenol (ING B) reactivates latent HIV better than SAHA, ingenol 3,20-dibenzoate, TNF-α, PMA and HMBA. • ING B promotes PKC activation and NF-kB translocation to the nucleus. • ING B activates virus transcription of B and non-B subtypes of HIV-1. • ING B activates HIV transcription in infected primary resting CD4+ T cells. • ING B induces higher levels of P-TEFb components in human primary cells.

  12. Detecting New Words from Chinese Text Using Latent Semi-CRF Models

    Science.gov (United States)

    Sun, Xiao; Huang, Degen; Ren, Fuji

    Chinese new words and their part-of-speech (POS) are particularly problematic in Chinese natural language processing. With the fast development of internet and information technology, it is impossible to get a complete system dictionary for Chinese natural language processing, as new words out of the basic system dictionary are always being created. A latent semi-CRF model, which combines the strengths of LDCRF (Latent-Dynamic Conditional Random Field) and semi-CRF, is proposed to detect the new words together with their POS synchronously regardless of the types of the new words from the Chinese text without being pre-segmented. Unlike the original semi-CRF, the LDCRF is applied to generate the candidate entities for training and testing the latent semi-CRF, which accelerates the training speed and decreases the computation cost. The complexity of the latent semi-CRF could be further adjusted by tuning the number of hidden variables in LDCRF and the number of the candidate entities from the Nbest outputs of the LDCRF. A new-words-generating framework is proposed for model training and testing, under which the definitions and distributions of the new words conform to the ones existing in real text. Specific features called “Global Fragment Information” for new word detection and POS tagging are adopted in the model training and testing. The experimental results show that the proposed method is capable of detecting even low frequency new words together with their POS tags. The proposed model is found to be performing competitively with the state-of-the-art models presented.

  13. Characterization of Chemokine Receptor Utilization of Viruses in the Latent Reservoir for Human Immunodeficiency Virus Type 1

    Science.gov (United States)

    Pierson, Theodore; Hoffman, Trevor L.; Blankson, Joel; Finzi, Diana; Chadwick, Karen; Margolick, Joseph B.; Buck, Christopher; Siliciano, Janet D.; Doms, Robert W.; Siliciano, Robert F.

    2000-01-01

    Latently infected resting CD4+ T cells provide a long-term reservoir for human immunodeficiency virus type 1 (HIV-1) and are likely to represent the major barrier to virus eradication in patients on combination antiretroviral therapy. The mechanisms by which viruses enter the latent reservoir and the nature of the chemokine receptors involved have not been determined. To evaluate the phenotype of the virus in this compartment with respect to chemokine receptor utilization, full-length HIV-1 env genes were cloned from latently infected cells and assayed functionally. We demonstrate that the majority of the viruses in the latent reservoir utilize CCR5 during entry, although utilization of several other receptors, including CXCR4, was observed. No alternative coreceptors were shown to be involved in a systematic fashion. Although R5 viruses are present in the latent reservoir, CCR5 was not expressed at high levels on resting CD4+ T cells. To understand the mechanism by which R5 viruses enter latent reservoir, the ability of an R5 virus, HIV-1 Ba-L, to infect highly purified resting CD4+ T lymphocytes from uninfected donors was evaluated. Entry of Ba-L could be observed when virus was applied at a multiplicity approaching 1. However, infection was limited to a subset of cells expressing low levels of CCR5 and markers of immunologic memory. Naive cells could not be infected by an R5 virus even when challenged with a large inoculum. Direct cell fractionation studies showed that latent virus is present predominantly in resting memory cells but also at lower levels in resting naive cells. Taken together, these findings provide support for the hypothesis that the direct infection of naive T cells is not the major mechanism by which the latent infection of resting T cells is established. PMID:10933689

  14. Latent log-linear models for handwritten digit classification.

    Science.gov (United States)

    Deselaers, Thomas; Gass, Tobias; Heigold, Georg; Ney, Hermann

    2012-06-01

    We present latent log-linear models, an extension of log-linear models incorporating latent variables, and we propose two applications thereof: log-linear mixture models and image deformation-aware log-linear models. The resulting models are fully discriminative, can be trained efficiently, and the model complexity can be controlled. Log-linear mixture models offer additional flexibility within the log-linear modeling framework. Unlike previous approaches, the image deformation-aware model directly considers image deformations and allows for a discriminative training of the deformation parameters. Both are trained using alternating optimization. For certain variants, convergence to a stationary point is guaranteed and, in practice, even variants without this guarantee converge and find models that perform well. We tune the methods on the USPS data set and evaluate on the MNIST data set, demonstrating the generalization capabilities of our proposed models. Our models, although using significantly fewer parameters, are able to obtain competitive results with models proposed in the literature.

  15. 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.

  16. Getting the "Kill" into "Shock and Kill": Strategies to Eliminate Latent HIV.

    Science.gov (United States)

    Kim, Youry; Anderson, Jenny L; Lewin, Sharon R

    2018-01-10

    Despite the success of antiretroviral therapy (ART), there is currently no HIV cure and treatment is life long. HIV persists during ART due to long-lived and proliferating latently infected CD4+ T cells. One strategy to eliminate latency is to activate virus production using latency reversing agents (LRAs) with the goal of triggering cell death through virus-induced cytolysis or immune-mediated clearance. However, multiple studies have demonstrated that activation of viral transcription alone is insufficient to induce cell death and some LRAs may counteract cell death by promoting cell survival. Here, we review new approaches to induce death of latently infected cells through apoptosis and inhibition of pathways critical for cell survival, which are often hijacked by HIV proteins. Given advances in the commercial development of compounds that induce apoptosis in cancer chemotherapy, these agents could move rapidly into clinical trials, either alone or in combination with LRAs, to eliminate latent HIV infection. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. How to get rid of W: a latent variables approach to modelling spatially lagged variables

    NARCIS (Netherlands)

    Folmer, H.; Oud, J.

    2008-01-01

    In this paper we propose a structural equation model (SEM) with latent variables to model spatial dependence. Rather than using the spatial weights matrix W, we propose to use latent variables to represent spatial dependence and spillover effects, of which the observed spatially lagged variables are

  18. How to get rid of W : a latent variables approach to modelling spatially lagged variables

    NARCIS (Netherlands)

    Folmer, Henk; Oud, Johan

    2008-01-01

    In this paper we propose a structural equation model (SEM) with latent variables to model spatial dependence. Rather than using the spatial weights matrix W, we propose to use latent variables to represent spatial dependence and spillover effects, of which the observed spatially lagged variables are

  19. The Latent Structure of Secure Base Script Knowledge

    Science.gov (United States)

    Waters, Theodore E. A.; Fraley, R. Chris; Groh, Ashley M.; Steele, Ryan D.; Vaughn, Brian E.; Bost, Kelly K.; Veríssimo, Manuela; Coppola, Gabrielle; Roisman, Glenn I.

    2015-01-01

    There is increasing evidence that attachment representations abstracted from childhood experiences with primary caregivers are organized as a cognitive script describing secure base use and support (i.e., the "secure base script"). To date, however, the latent structure of secure base script knowledge has gone unexamined--this despite…

  20. Latent Partially Ordered Classification Models and Normal Mixtures

    Science.gov (United States)

    Tatsuoka, Curtis; Varadi, Ferenc; Jaeger, Judith

    2013-01-01

    Latent partially ordered sets (posets) can be employed in modeling cognitive functioning, such as in the analysis of neuropsychological (NP) and educational test data. Posets are cognitively diagnostic in the sense that classification states in these models are associated with detailed profiles of cognitive functioning. These profiles allow for…

  1. A latent transition model of the effects of a teen dating violence prevention initiative.

    Science.gov (United States)

    Williams, Jason; Miller, Shari; Cutbush, Stacey; Gibbs, Deborah; Clinton-Sherrod, Monique; Jones, Sarah

    2015-02-01

    Patterns of physical and psychological teen dating violence (TDV) perpetration, victimization, and related behaviors were examined with data from the evaluation of the Start Strong: Building Healthy Teen Relationships initiative, a dating violence primary prevention program targeting middle school students. Latent class and latent transition models were used to estimate distinct patterns of TDV and related behaviors of bullying and sexual harassment in seventh grade students at baseline and to estimate transition probabilities from one pattern of behavior to another at the 1-year follow-up. Intervention effects were estimated by conditioning transitions on exposure to Start Strong. Latent class analyses suggested four classes best captured patterns of these interrelated behaviors. Classes were characterized by elevated perpetration and victimization on most behaviors (the multiproblem class), bullying perpetration/victimization and sexual harassment victimization (the bully-harassment victimization class), bullying perpetration/victimization and psychological TDV victimization (bully-psychological victimization), and experience of bully victimization (bully victimization). Latent transition models indicated greater stability of class membership in the comparison group. Intervention students were less likely to transition to the most problematic pattern and more likely to transition to the least problem class. Although Start Strong has not been found to significantly change TDV, alternative evaluation models may find important differences. Latent transition analysis models suggest positive intervention impact, especially for the transitions at the most and the least positive end of the spectrum. Copyright © 2015. Published by Elsevier Inc.

  2. Reactivation of Latent Epstein-Barr Virus; A Comparison After Gamma Rays and Proton Treatment

    Science.gov (United States)

    Mehta, Satish K.; Plante, Ianik; Bloom, David C.; Stowe, Raymond; Renner, Ashlie; Wu, Honglu; Crucian, Brian; Pierson, Duane L.

    2017-01-01

    Among different unique stressors astronauts are exposed to during spaceflight, cosmic radiation constitutes an important one that leads to various health effects. In particular, space radiation may contribute to decreased immunity, which has been observed in astronauts during short and long duration missions, as evidenced by several changes in cellular immunity and plasma cytokines levels. Reactivation of latent herpes viruses, either directly from radiation or resulting from perturbation in the immune system, is also observed in astronauts. While EBV is one of the eight human herpes viruses known to infect more than 90% human adults and stays latent for the life of the host without normally causing adverse effects of reactivation, increased reactivation in astronauts is well-documented, though the mechanism of this increase is not understood. In this work, we have studied the effect of two different types of radiations, Cs-137 gamma and 150-MeV proton on the reactivation rates of the Epstein - Barr virus (EBV) in vitro in EBV latent cell lines at doses of 0.1, 0.5, 1.0 and 2.0 Gy. While we find that both types of radiations reactivated latent EBV in vitro, we observe that at equivalent doses, early response is stronger for protons but with time, the reactivation induced by gamma rays is more persistent. These differences between the protons and gamma rays curves in latent virus reactivation challenge the common paradigm that protons and gamma rays have similar biological effects.

  3. Mycobacteria-specific cytokine responses as correlates of treatment response in active and latent tuberculosis.

    Science.gov (United States)

    Clifford, Vanessa; Tebruegge, Marc; Zufferey, Christel; Germano, Susie; Forbes, Ben; Cosentino, Lucy; McBryde, Emma; Eisen, Damon; Robins-Browne, Roy; Street, Alan; Denholm, Justin; Curtis, Nigel

    2017-08-01

    A biomarker indicating successful tuberculosis (TB) therapy would assist in determining appropriate length of treatment. This study aimed to determine changes in mycobacteria-specific antigen-induced cytokine biomarkers in patients receiving therapy for latent or active TB, to identify biomarkers potentially correlating with treatment success. A total of 33 adults with active TB and 36 with latent TB were followed longitudinally over therapy. Whole blood stimulation assays using mycobacteria-specific antigens (CFP-10, ESAT-6, PPD) were done on samples obtained at 0, 1, 3, 6 and 9 months. Cytokine responses (IFN-γ, IL-1ra, IL-2, IL-10, IL-13, IP-10, MIP-1β, and TNF-α) in supernatants were measured by Luminex xMAP immunoassay. In active TB cases, median IL-1ra (with CFP-10 and with PPD stimulation), IP-10 (CFP-10, ESAT-6), MIP-1β (ESAT-6, PPD), and TNF-α (ESAT-6) responses declined significantly over the course of therapy. In latent TB cases, median IL-1ra (CFP-10, ESAT-6, PPD), IL-2 (CFP-10, ESAT-6), and IP-10 (CFP-10, ESAT-6) responses declined significantly. Mycobacteria-specific cytokine responses change significantly over the course of therapy, and their kinetics in active TB differ from those observed in latent TB. In particular, mycobacteria-specific IL-1ra responses are potential correlates of successful therapy in both active and latent TB. Copyright © 2017 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

  4. Forensic applications of infrared imaging for the detection and recording of latent evidence.

    Science.gov (United States)

    Lin, Apollo Chun-Yen; Hsieh, Hsing-Mei; Tsai, Li-Chin; Linacre, Adrian; Lee, James Chun-I

    2007-09-01

    We report on a simple method to record infrared (IR) reflected images in a forensic science context. Light sources using ultraviolet light have been used previously in the detection of latent prints, but the use of infrared light has been subjected to less investigation. IR light sources were used to search for latent evidence and the images were captured by either video or using a digital camera with a CCD array sensitive to IR wavelength. Bloodstains invisible to the eye, inks, tire prints, gunshot residue, and charred document on dark background are selected as typical matters that may be identified during a forensic investigation. All the evidence types could be detected and identified using a range of photographic techniques. In this study, a one in eight times dilution of blood could be detected on 10 different samples of black cloth. When using 81 black writing inks, the observation rates were 95%, 88% and 42% for permanent markers, fountain pens and ball-point pens, respectively, on the three kinds of dark cloth. The black particles of gunshot residue scattering around the entrance hole under IR light were still observed at a distance of 60 cm from three different shooting ranges. A requirement of IR reflectivity is that there is a contrast between the latent evidence and the background. In the absence of this contrast no latent image will be detected, which is similar to all light sources. The use of a video camera allows the recording of images either at a scene or in the laboratory. This report highlights and demonstrates the robustness of IR to detect and record the presence of latent evidence.

  5. Altered intrinsic functional connectivity in the latent period of epileptogenesis in a temporal lobe epilepsy model.

    Science.gov (United States)

    Lee, Hyoin; Jung, Seungmoon; Lee, Peter; Jeong, Yong

    2017-10-01

    The latent period, a seizure-free phase, is the duration between brain injury and the onset of spontaneous recurrent seizures (SRSs) during epileptogenesis. The latent period is thought to involve several progressive pathophysiological events that lead to the evolution of the chronic epilepsy phase. Hence, it is vital to investigate the changes in the latent period during epileptogenesis in order to better understand temporal lobe epilepsy (TLE), and to achieve early diagnosis and appropriate management of the condition. Accordingly, recent studies with patients with TLE using resting-state functional magnetic resonance imaging (rs-fMRI) have reported that alterations of resting-state functional connectivity (rsFC) during the chronic period are associated with some clinical manifestations, including learning and memory impairments, emotional instability, and social behavior deficits, in addition to repetitive seizure episodes. In contrast, the changes in the intrinsic rsFC during epileptogenesis, particularly during the latent period, remain unclear. In this study, we investigated the alterations in intrinsic rsFC during the latent and chronic periods in a pilocarpine-induced TLE mouse model using intrinsic optical signal imaging (IOSI). This technique can monitor the changes in the local hemoglobin concentration according to neuronal activity and can help investigate large-scale brain intrinsic networks. After seeding on the anatomical regions of interest (ROIs) and calculating the correlation coefficients between each ROI, we established and compared functional correlation matrices and functional connectivity maps during the latent and chronic periods of epilepsy. We found a decrease in the interhemispheric rsFC at the frontal and temporal regions during both the latent and chronic periods. Furthermore, a significant decrease in the interhemispheric rsFC was observed in the somatosensory area during the chronic period. Changes in network configurations during

  6. Proximate Composition, Nutritional Attributes and Mineral Composition of <em>Peperomia> <em>pellucida> L. (Ketumpangan Air Grown in Malaysia

    Directory of Open Access Journals (Sweden)

    Maznah Ismail

    2012-09-01

    Full Text Available This study presents the proximate and mineral composition of <em>Peperomia> <em>pellucida> L., an underexploited weed plant in Malaysia. Proximate analysis was performed using standard AOAC methods and mineral contents were determined using atomic absorption spectrometry. The results indicated <em>Peperomia> <em>pellucida> to be rich in crude protein, carbohydrate and total ash contents. The high amount of total ash (31.22% suggests a high-value mineral composition comprising potassium, calcium and iron as the main elements. The present study inferred that <em>Peperomia> <em>pellucida> would serve as a good source of protein and energy as well as micronutrients in the form of a leafy vegetable for human consumption.

  7. Evaluation of Antioxidant Activities of Aqueous Extracts and Fractionation of Different Parts of <em>Elsholtzia em>ciliata>

    Directory of Open Access Journals (Sweden)

    Yuangang Zu

    2012-05-01

    Full Text Available The aim of this study was to investigate the antioxidant and free-radical scavenging activity of extract and fractions from various parts of <em>Elsholtzia ciliataem>. The inflorescences, leaves, stems and roots of <em>E. ciliataem> were extracted separately and two phenolic component enrichment methods: ethyl acetate-water liquid-liquid extraction and macroporous resin adsorption-desorption, were adopted in this study. The antioxidant activities of water extracts and fractions of <em>E. ciliataem> were examined using different assay model systems <em>in vitroem>. The fraction root E (purified by HPD300 macroporous resin exhibited the highest total phenolics content (497.2 ± 24.9 mg GAE/g, accompanied with the highest antioxidant activity against various antioxidant systems <em>in vitroem> compared to other fractions. On the basis of the results obtained, <em>E. ciliataem> extracts can be used potentially as a ready accessible and valuable bioactive source of natural antioxidants.

  8. Um estudo de follow up em psicoterapia psicanalítica de casais

    Directory of Open Access Journals (Sweden)

    Maria Galrão Rios

    2011-04-01

    Full Text Available Por 11 anos desenvolvemos uma pesquisa envolvendo uma proposta interventiva com famílias que buscam atendimento em um serviço-escola, com demanda localizada na criança. Por meio da psicoterapia psicanalítica com o casal procuramos atingir a remissão dos sintomas do(s filho(s. O objetivo deste estudo é refletir sobre a manutenção das mudanças psíquicas ocorridas nesse tipo de clínica, que abrange a esfera conjugal e familiar, ao longo do tempo. Com base na metodologia de estudo de caso e no referencial psicanalítico, foram analisados dois casos clínicos enfatizando-se as sessões de follow up: dois casais que estiveram em processo terapêutico, respectivamente, por três anos e por dois anos e meio, sendo realizadas duas sessões de acompanhamento após o término da terapia. Esse tipo de intervenção mostrou-se efetiva para a elucidação de conflitos conjugais latentes e como promovedora de um ambiente saudável e favorecedor do desenvolvimento emocional da criança.

  9. A Modified Electrostatic Adsorption Apparatus for Latent Fingerprint Development on Unfired Cartridge Cases.

    Science.gov (United States)

    Xu, Jingyang; Zhang, Ziyuan; Zheng, Xiaochun; Bond, John W

    2017-05-01

    Visualization of latent fingerprints on metallic surfaces by the method of applying electrostatic charging and adsorption is considered as a promising chemical-free method, which has the merit of nondestruction, and is considered to be effective for some difficult situations such as aged fingerprint deposits or those exposed to environmental extremes. In fact, a portable electrostatic generator can be easily accessible in a local forensic technology laboratory, which is already widely used in the visualization of footwear impressions. In this study, a modified version of this electrostatic apparatus is proposed for latent fingerprint development and has shown great potential in visualizing fingerprints on metallic surfaces such as cartridge cases. Results indicate that this experimental arrangement can successfully develop aged latent fingerprints on metal surfaces, and we demonstrate its effectiveness compared with existing conventional fingerprint recovery methods. © 2016 American Academy of Forensic Sciences.

  10. Does Attention-Deficit/Hyperactivity Disorder Have a Dimensional Latent Structure? A Taxometric Analysis

    Science.gov (United States)

    Marcus, David K.; Barry, Tammy D.

    2010-01-01

    An understanding of the latent structure of attention-deficit/hyperactivity disorder (ADHD) is essential for developing causal models of this disorder. Although some researchers have presumed that ADHD is dimensional and others have assumed that it is taxonic, there has been relatively little research directly examining the latent structure of ADHD. The authors conducted a set of taxometric analyses using data from the NICHD Study of Early Child Care and Youth Development (ns between 667–1078). The results revealed a dimensional latent structure across a variety of different analyses and sets of indicators, for inattention, hyperactivity/impulsivity, and ADHD. Furthermore, analyses of correlations with associated features indicated that dimensional models demonstrated stronger validity coefficients with these criterion measures than dichotomous models. These findings jibe with recent research on the genetic basis of ADHD and with contemporary models of ADHD. PMID:20973595

  11. A Bayesian approach to estimate sensible and latent heat over vegetated land surface

    Directory of Open Access Journals (Sweden)

    C. van der Tol

    2009-06-01

    Full Text Available Sensible and latent heat fluxes are often calculated from bulk transfer equations combined with the energy balance. For spatial estimates of these fluxes, a combination of remotely sensed and standard meteorological data from weather stations is used. The success of this approach depends on the accuracy of the input data and on the accuracy of two variables in particular: aerodynamic and surface conductance. This paper presents a Bayesian approach to improve estimates of sensible and latent heat fluxes by using a priori estimates of aerodynamic and surface conductance alongside remote measurements of surface temperature. The method is validated for time series of half-hourly measurements in a fully grown maize field, a vineyard and a forest. It is shown that the Bayesian approach yields more accurate estimates of sensible and latent heat flux than traditional methods.

  12. Does attention-deficit/hyperactivity disorder have a dimensional latent structure? A taxometric analysis.

    Science.gov (United States)

    Marcus, David K; Barry, Tammy D

    2011-05-01

    An understanding of the latent structure of attention-deficit/hyperactivity disorder (ADHD) is essential for developing causal models of this disorder. Although some researchers have presumed that ADHD is dimensional and others have assumed that it is taxonic, there has been relatively little research directly examining the latent structure of ADHD. The authors conducted a set of taxometric analyses using data from the NICHD Study of Early Child Care and Youth Development (ns between 667 and 1,078). The results revealed a dimensional latent structure across a variety of different analyses and sets of indicators for inattention, hyperactivity/impulsivity, and ADHD. Furthermore, analyses of correlations with associated features indicated that dimensional models demonstrated stronger validity coefficients with these criterion measures than dichotomous models. These findings jibe with recent research on the genetic basis of ADHD and with contemporary models of ADHD.

  13. 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....

  14. Experimental Examination of Bacteriophage Latent-Period Evolution as a Response to Bacterial Availability

    OpenAIRE

    Abedon, Stephen T.; Hyman, Paul; Thomas, Cameron

    2003-01-01

    For obligately lytic bacteriophage (phage) a trade-off exists between fecundity (burst size) and latent period (a component of generation time). This trade-off occurs because release of phage progeny from infected bacteria coincides with destruction of the machinery necessary to produce more phage progeny. Here we employ phage mutants to explore issues of phage latent-period evolution as a function of the density of phage-susceptible bacteria. Theory suggests that higher bacterial densities s...

  15. Prevalence and risk factors of latent Tuberculosis among ...

    African Journals Online (AJOL)

    termine the risk factors of prevalent LTBI. We used a mixed effects binomial model with a logarithmic link function to estimate prevalence ratios (PR) for risk fac- tors of latent tuberculosis infection (LTBI). Ethical consideration. The study was approved by the Makerere University. School of Public Health–Higher Degrees and ...

  16. Effect Of Prolonged Monocular Occlusion On Latent Nystagms

    NARCIS (Netherlands)

    H.J. Simonsz (Huib); G. Kommerell (Guntram)

    1992-01-01

    textabstractThe authors recorded nystagmus during seeing with one eye in eight patients with latent nystagmus (LN) before and after two or three days of prolonged occlusion of the better eye (POBE). Before POBE, the slow-phase speed of the nystagmus (SPS) was usually higher when the better eye was

  17. Association of Stressful Life Events with Psychological Problems: A Large-Scale Community-Based Study Using Grouped Outcomes Latent Factor Regression with Latent Predictors

    Directory of Open Access Journals (Sweden)

    Akbar Hassanzadeh

    2017-01-01

    Full Text Available Objective. The current study is aimed at investigating the association between stressful life events and psychological problems in a large sample of Iranian adults. Method. In a cross-sectional large-scale community-based study, 4763 Iranian adults, living in Isfahan, Iran, were investigated. Grouped outcomes latent factor regression on latent predictors was used for modeling the association of psychological problems (depression, anxiety, and psychological distress, measured by Hospital Anxiety and Depression Scale (HADS and General Health Questionnaire (GHQ-12, as the grouped outcomes, and stressful life events, measured by a self-administered stressful life events (SLEs questionnaire, as the latent predictors. Results. The results showed that the personal stressors domain has significant positive association with psychological distress (β=0.19, anxiety (β=0.25, depression (β=0.15, and their collective profile score (β=0.20, with greater associations in females (β=0.28 than in males (β=0.13 (all P<0.001. In addition, in the adjusted models, the regression coefficients for the association of social stressors domain and psychological problems profile score were 0.37, 0.35, and 0.46 in total sample, males, and females, respectively (P<0.001. Conclusion. Results of our study indicated that different stressors, particularly those socioeconomic related, have an effective impact on psychological problems. It is important to consider the social and cultural background of a population for managing the stressors as an effective approach for preventing and reducing the destructive burden of psychological problems.

  18. Association of Stressful Life Events with Psychological Problems: A Large-Scale Community-Based Study Using Grouped Outcomes Latent Factor Regression with Latent Predictors

    Science.gov (United States)

    Hassanzadeh, Akbar; Heidari, Zahra; Hassanzadeh Keshteli, Ammar; Afshar, Hamid

    2017-01-01

    Objective The current study is aimed at investigating the association between stressful life events and psychological problems in a large sample of Iranian adults. Method In a cross-sectional large-scale community-based study, 4763 Iranian adults, living in Isfahan, Iran, were investigated. Grouped outcomes latent factor regression on latent predictors was used for modeling the association of psychological problems (depression, anxiety, and psychological distress), measured by Hospital Anxiety and Depression Scale (HADS) and General Health Questionnaire (GHQ-12), as the grouped outcomes, and stressful life events, measured by a self-administered stressful life events (SLEs) questionnaire, as the latent predictors. Results The results showed that the personal stressors domain has significant positive association with psychological distress (β = 0.19), anxiety (β = 0.25), depression (β = 0.15), and their collective profile score (β = 0.20), with greater associations in females (β = 0.28) than in males (β = 0.13) (all P < 0.001). In addition, in the adjusted models, the regression coefficients for the association of social stressors domain and psychological problems profile score were 0.37, 0.35, and 0.46 in total sample, males, and females, respectively (P < 0.001). Conclusion Results of our study indicated that different stressors, particularly those socioeconomic related, have an effective impact on psychological problems. It is important to consider the social and cultural background of a population for managing the stressors as an effective approach for preventing and reducing the destructive burden of psychological problems. PMID:29312459

  19. Tissue-specific control of latent CMV reactivation by regulatory T cells.

    Directory of Open Access Journals (Sweden)

    Maha Almanan

    2017-08-01

    Full Text Available Cytomegalovirus (CMV causes a persistent, lifelong infection. CMV persists in a latent state and undergoes intermittent subclinical viral reactivation that is quelled by ongoing T cell responses. While T cells are critical to maintain control of infection, the immunological factors that promote CMV persistence remain unclear. Here, we investigated the role of regulatory T cells (Treg in a mouse model of latent CMV infection using Foxp3-diphtheria toxin receptor (Foxp3-DTR mice. Eight months after infection, MCMV had established latency in the spleen, salivary gland, lung, and pancreas, which was accompanied by an increased frequency of Treg. Administration of diphtheria toxin (DT after establishment of latency efficiently depleted Treg and drove a significant increase in the numbers of functional MCMV-specific CD4+ and CD8+ T cells. Strikingly, Treg depletion decreased the number of animals with reactivatable latent MCMV in the spleen. Unexpectedly, in the same animals, ablation of Treg drove a significant increase in viral reactivation in the salivary gland that was accompanied with augmented local IL-10 production by Foxp3-CD4+T cells. Further, neutralization of IL-10 after Treg depletion significantly decreased viral load in the salivary gland. Combined, these data show that Treg have divergent control of MCMV infection depending upon the tissue. In the spleen, Treg antagonize CD8+ effector function and promote viral persistence while in the salivary gland Treg prevent IL-10 production and limit viral reactivation and replication. These data provide new insights into the organ-specific roles of Treg in controlling the reactivation of latent MCMV infection.

  20. Short-term memory development: differences in serial position curves between age groups and latent classes.

    Science.gov (United States)

    Koppenol-Gonzalez, Gabriela V; Bouwmeester, Samantha; Vermunt, Jeroen K

    2014-10-01

    In studies on the development of cognitive processes, children are often grouped based on their ages before analyzing the data. After the analysis, the differences between age groups are interpreted as developmental differences. We argue that this approach is problematic because the variance in cognitive performance within an age group is considered to be measurement error. However, if a part of this variance is systematic, it can provide very useful information about the cognitive processes used by some children of a certain age but not others. In the current study, we presented 210 children aged 5 to 12 years with serial order short-term memory tasks. First we analyze our data according to the approach using age groups, and then we apply latent class analysis to form latent classes of children based on their performance instead of their ages. We display the results of the age groups and the latent classes in terms of serial position curves, and we discuss the differences in results. Our findings show that there are considerable differences in performance between the age groups and the latent classes. We interpret our findings as indicating that the latent class analysis yielded a much more meaningful way of grouping children in terms of cognitive processes than the a priori grouping of children based on their ages. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Allometric and Isometric variations in the Italian <em>Apodemus sylvaticusem> and <em>Apodemus flavicollisem> with respect to the conditions of allopatry and sympatry / Variazioni allometriche e isometriche in <em>Apodemus sylvaticusem> e <em>Apodemus flavicollisem> italiani, rispetto alle condizioni di allopatria e simpatria

    Directory of Open Access Journals (Sweden)

    Giovanni Amori

    1986-12-01

    Full Text Available Abstract In Italy there are two species of <em>Apodemus> (<em>Sylvaemus>: <em>Apodemus sylvaticusem> on the mainland and the main island, and <em>Apodemus flavicollisem> only on the mainland. The trend of some morphometric characters of the skull (incisive foramen length - FI; interorbital breadth = IO; length of palatal bridge = PP; upper alveolar length = $M^1M^3$ was analized and some theoretical models verified for <em>A. sylvaticusem>. If one considers the sympatric population of <em>A. sylvaticusem> and <em>A. flavicollisem> simultaneously the characters PP, IO and $M^1M^3$ appear significantly isometric being directly correlated ($P leq O.O1$, while FI character results allometric with respect to the previous ones, as expected. If one considers the sympatric populations of each of the species separately, the scenario is different. For <em>A. sylvaticusem> only PP and $M^1M^3$ are isometric ($P leq 0.05$. For <em>A. flavicollisem> only $M^1M^3$ and FI appear to be correlated, although not as significantly as for <em>A. sylvaticusem> ($P le 0.05$; one tail. The insular populations of <em>A. sylvaticusem> do not show significant correlations, except for FI and $M^1M^3$ ($P le 0.05$. On the contrary, considering all populations, sympatric and allopatric, of <em>A. sylvaticusem> at the same time are significant correlations ($P le 0.05$ in all combinations of characters, except for those involving the IO. We suggest that the isometric relations in sympatric assemblages are confined within a morphological range available to the genus <em>Apodemus>. In such a space, the two species are split in two different and innerly homogeneous distributions. We found no evidence to confirm the niche variation hypothesis. On the contrary, the variability expressed as SO or CV's appears higher in the sympatric populations than in the allopatric ones, for three of the four characters, confirming previous results

  2. Bayesian leave-one-out cross-validation approximations for Gaussian latent variable models

    DEFF Research Database (Denmark)

    Vehtari, Aki; Mononen, Tommi; Tolvanen, Ville

    2016-01-01

    The future predictive performance of a Bayesian model can be estimated using Bayesian cross-validation. In this article, we consider Gaussian latent variable models where the integration over the latent values is approximated using the Laplace method or expectation propagation (EP). We study...... the properties of several Bayesian leave-one-out (LOO) cross-validation approximations that in most cases can be computed with a small additional cost after forming the posterior approximation given the full data. Our main objective is to assess the accuracy of the approximative LOO cross-validation estimators...

  3. A Novel Apoptosis Correlated Molecule: Expression and Characterization of Protein Latcripin-1 from <em>Lentinula em>edodes> C91–3

    Directory of Open Access Journals (Sweden)

    Min Huang

    2012-05-01

    Full Text Available An apoptosis correlated molecule—protein Latcripin-1 of <em>Lentinula> edodesem> C91-3—was expressed and characterized in <em>Pichia pastorisem> GS115. The total RNA was obtained from <em>Lentinula edodesem> C91–3. According to the transcriptome, the full-length gene of Latcripin-1 was isolated with 3'-Full Rapid Amplification of cDNA Ends (RACE and 5'-Full RACE methods. The full-length gene was inserted into the secretory expression vector pPIC9K. The protein Latcripin-1 was expressed in <em>Pichia pastorisem> GS115 and analyzed by Sodium Dodecylsulfonate Polyacrylate Gel Electrophoresis (SDS-PAGE and Western blot. The Western blot showed that the protein was expressed successfully. The biological function of protein Latcripin-1 on A549 cells was studied with flow cytometry and the 3-(4,5-Dimethylthiazol-2-yl-2,5-Diphenyl-tetrazolium Bromide (MTT method. The toxic effect of protein Latcripin-1 was detected with the MTT method by co-culturing the characterized protein with chick embryo fibroblasts. The MTT assay results showed that there was a great difference between protein Latcripin-1 groups and the control group (<em>p em>< 0.05. There was no toxic effect of the characterized protein on chick embryo fibroblasts. The flow cytometry showed that there was a significant difference between the protein groups of interest and the control group according to apoptosis function (<em>p em>< 0.05. At the same time, cell ultrastructure observed by transmission electron microscopy supported the results of flow cytometry. The work demonstrates that protein Latcripin-1 can induce apoptosis of human lung cancer cells A549 and brings new insights into and advantages to finding anti-tumor proteins.

  4. 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…

  5. Studies of Latent Acidity and Neutral Buffered Chloroaluminate Ionic Liquids

    National Research Council Canada - National Science Library

    Osteryoung, Robert

    2000-01-01

    Studies on ionic liquids composed of aluminum chloride and 1-ethyl-3-methylimidazolium chloride were carried out, with emphasis on understanding and explaining acidity and latent acidity in "neutral buffered" melts...

  6. GARP (LRRC32) is essential for the surface expression of latent TGF-β on platelets and activated FOXP3+ regulatory T cells

    Science.gov (United States)

    Tran, Dat Q.; Andersson, John; Wang, Rui; Ramsey, Heather; Unutmaz, Derya; Shevach, Ethan M.

    2009-01-01

    TGF-β family members are highly pleiotropic cytokines with diverse regulatory functions. TGF-β is normally found in the latent form associated with latency-associated peptide (LAP). This latent complex can associate with latent TGFβ-binding protein (LTBP) to produce a large latent form. Latent TGF-β is also found on the surface of activated FOXP3+ regulatory T cells (Tregs), but it is unclear how it is anchored to the cell membrane. We show that GARP or LRRC32, a leucine-rich repeat molecule of unknown function, is critical for tethering TGF-β to the cell surface. We demonstrate that platelets and activated Tregs co-express latent TGF-β and GARP on their membranes. The knockdown of GARP mRNA with siRNA prevented surface latent TGF-β expression on activated Tregs and recombinant latent TGF-β1 is able to bind directly with GARP. Confocal microscopy and immunoprecipitation strongly support their interactions. The role of TGF-β on Tregs appears to have dual functions, both for Treg-mediated suppression and infectious tolerance mechanism. PMID:19651619

  7. GARP (LRRC32) is essential for the surface expression of latent TGF-beta on platelets and activated FOXP3+ regulatory T cells.

    Science.gov (United States)

    Tran, Dat Q; Andersson, John; Wang, Rui; Ramsey, Heather; Unutmaz, Derya; Shevach, Ethan M

    2009-08-11

    TGF-beta family members are highly pleiotropic cytokines with diverse regulatory functions. TGF-beta is normally found in the latent form associated with latency-associated peptide (LAP). This latent complex can associate with latent TGFbeta-binding protein (LTBP) to produce a large latent form. Latent TGF-beta is also found on the surface of activated FOXP3(+) regulatory T cells (Tregs), but it is unclear how it is anchored to the cell membrane. We show that GARP or LRRC32, a leucine-rich repeat molecule of unknown function, is critical for tethering TGF-beta to the cell surface. We demonstrate that platelets and activated Tregs co-express latent TGF-beta and GARP on their membranes. The knockdown of GARP mRNA with siRNA prevented surface latent TGF-beta expression on activated Tregs and recombinant latent TGF-beta1 is able to bind directly with GARP. Confocal microscopy and immunoprecipitation strongly support their interactions. The role of TGF-beta on Tregs appears to have dual functions, both for Treg-mediated suppression and infectious tolerance mechanism.

  8. A model for the latent heat of melting in free standing metal nanoparticles

    International Nuclear Information System (INIS)

    Shin, Jeong-Heon; Deinert, Mark R.

    2014-01-01

    Nanoparticles of many metals are known to exhibit scale dependent latent heats of melting. Analytical models for this phenomenon have so far failed to completely capture the observed phenomena. Here we present a thermodynamic analysis for the melting of metal nanoparticles in terms of their internal energy and a scale dependent surface tension proposed by Tolman. The resulting model predicts the scale dependence of the latent heat of melting and is confirmed using published data for tin and aluminum

  9. GARP (LRRC32) is essential for the surface expression of latent TGF-β on platelets and activated FOXP3+ regulatory T cells

    OpenAIRE

    Tran, Dat Q.; Andersson, John; Wang, Rui; Ramsey, Heather; Unutmaz, Derya; Shevach, Ethan M.

    2009-01-01

    TGF-β family members are highly pleiotropic cytokines with diverse regulatory functions. TGF-β is normally found in the latent form associated with latency-associated peptide (LAP). This latent complex can associate with latent TGFβ-binding protein (LTBP) to produce a large latent form. Latent TGF-β is also found on the surface of activated FOXP3+ regulatory T cells (Tregs), but it is unclear how it is anchored to the cell membrane. We show that GARP or LRRC32, a leucine-rich repeat molecule ...

  10. Investigating design: A comparison of manifest and latent approaches

    DEFF Research Database (Denmark)

    Cash, Philip; Snider, Chris

    2014-01-01

    This paper contributes to the on-going focus on improving design research methods, by exploring and synthesising two key interrelated research approaches e manifest and latent. These approaches are widely used individually in design research, however, this paper represents the first work bringing...

  11. Use of potassium silicate for powdery mildew control in Eucalyptus benthamii seedlings Uso do silicato de potássio no controle de oídio em mudas de Eucalyptus benthamii

    Directory of Open Access Journals (Sweden)

    Bruno Schultz

    2012-03-01

    Full Text Available

    Avaliou-se a efetividade do silicato de potássio (K2SiO3 no controle de oídio em mudas de <em>Eucalyptus benthamiiem>. Quatro tratamentos foram testados: pulverização de K2SiO3 (4 mL L-1 por 7 dias, pulverização de K2SiO3 (4 mL L-1 por 14 dias, pulverização do fungicida epoxiconazole + piraclostrobina (6 mL L-1 por 14 dias e pulverização de água ultrapurificada por 7 dias. Dez mudas com 90 dias de idade foram utilizadas por parcela em três blocos ao acaso. A inoculação foi feita pincelando-se esporos de <em>Oidium eucalyptiem>, retirados de mudas de <em>E. benthamiiem> já infectadas, sobre aspartes superiores de mudas sadias. Aos 150 dias, avaliou-se a severidade da doença e determinou-se a

  12. Estimate of the latent flux by the energy balance in protected cultivation of sweet pepper

    International Nuclear Information System (INIS)

    Cunha, A.R. da; Escobedo, J.F.; Klosowski, E.S.

    2002-01-01

    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 field. Available net radiation and energy losses were also lower in protected cultivation, showing a higher water use efficiency. (author) [pt

  13. Latency-Associated Expression of Human Cytomegalovirus US28 Attenuates Cell Signaling Pathways To Maintain Latent Infection

    Directory of Open Access Journals (Sweden)

    Benjamin A. Krishna

    2017-12-01

    Full Text Available Reactivation of human cytomegalovirus (HCMV latent infection from early myeloid lineage cells constitutes a threat to immunocompromised or immune-suppressed individuals. Consequently, understanding the control of latency and reactivation to allow targeting and killing of latently infected cells could have far-reaching clinical benefits. US28 is one of the few viral genes that is expressed during latency and encodes a cell surface G protein-coupled receptor (GPCR, which, during lytic infection, is a constitutive cell-signaling activator. Here we now show that in monocytes, which are recognized sites of HCMV latency in vivo, US28 attenuates multiple cell signaling pathways, including mitogen-activated protein (MAP kinase and NF-κB, and that this is required to establish a latent infection; viruses deleted for US28 initiate a lytic infection in infected monocytes. We also show that these monocytes then become potent targets for the HCMV-specific host immune response and that latently infected cells treated with an inverse agonist of US28 also reactivate lytic infection and similarly become immune targets. Consequently, we suggest that the use of inhibitors of US28 could be a novel immunotherapeutic strategy to reactivate the latent viral reservoir, allowing it to be targeted by preexisting HCMV-specific T cells.

  14. Detecting Latent Prints on Stone and Other Difficult Porous Surfaces via Indanedione/Zinc Chloride and Laser

    Directory of Open Access Journals (Sweden)

    Shiquan LIU

    2016-01-01

    Full Text Available Lasers and alternate light sources have been recognized as effective tools for latent print detection for over three decades. Luminescence often increases friction ridge contrast to reveal impressions otherwise undetectable. Indanedione/zinc chloride excited by a forensic light source is widely recognized as an effective process for developing latent prints on porous surfaces. This study was designed to evaluate the use of a combination of luminescence excitation and indanedione with zinc chloride to detect latent prints on stones, bricks, and similar difficult porous surfaces. The wavelengths evaluated included 400 nm (violet, 447 nm (blue, 532 nm (green, and 645 nm (red. Latent prints were deposited on a variety of porous surfaces including bricks, cement stones, wood, and cotton fabric, all commonly encountered at crime scenes in China. The surfaces were examined using white light (light-emitting diode flashlight and laser light sources separately, both before and after treatment with indanedione/zinc chloride. The goal of this study was to evaluate various light sources for their effectiveness in detecting impressions developed by indanedione/zinc chloride on difficult porous surfaces. Results indicated that latent prints on some brick and cement stone surfaces may be effectively detected using 532 nm laser excitation after indanedione/zinc chloride processing.

  15. Latent variable method for automatic adaptation to background states in motor imagery BCI

    Science.gov (United States)

    Dagaev, Nikolay; Volkova, Ksenia; Ossadtchi, Alexei

    2018-02-01

    Objective. Brain-computer interface (BCI) systems are known to be vulnerable to variabilities in background states of a user. Usually, no detailed information on these states is available even during the training stage. Thus there is a need in a method which is capable of taking background states into account in an unsupervised way. Approach. We propose a latent variable method that is based on a probabilistic model with a discrete latent variable. In order to estimate the model’s parameters, we suggest to use the expectation maximization algorithm. The proposed method is aimed at assessing characteristics of background states without any corresponding data labeling. In the context of asynchronous motor imagery paradigm, we applied this method to the real data from twelve able-bodied subjects with open/closed eyes serving as background states. Main results. We found that the latent variable method improved classification of target states compared to the baseline method (in seven of twelve subjects). In addition, we found that our method was also capable of background states recognition (in six of twelve subjects). Significance. Without any supervised information on background states, the latent variable method provides a way to improve classification in BCI by taking background states into account at the training stage and then by making decisions on target states weighted by posterior probabilities of background states at the prediction stage.

  16. Straightforward fabrication of black nano silica dusting powder for latent fingerprint imaging

    Science.gov (United States)

    Komalasari, Isna; Krismastuti, Fransiska Sri Herwahyu; Elishian, Christine; Handayani, Eka Mardika; Nugraha, Willy Cahya; Ketrin, Rosi

    2017-11-01

    Imaging of latent fingerprint pattern (aka fingermark) is one of the most important and accurate detection methods in forensic investigation because of the characteristic of individual fingerprint. This detection technique relies on the mechanical adherence of fingerprint powder to the moisture and oily component of the skin left on the surface. The particle size of fingerprint powder is one of the critical parameter to obtain excellent fingerprint image. This study develops a simple, cheap and straightforward method to fabricate Nano size black dusting fingerprint powder based on Nano silica and applies the powder to visualize latent fingerprint. The nanostructured silica was prepared from tetraethoxysilane (TEOS) and then modified with Nano carbon, methylene blue and sodium acetate to color the powder. Finally, as a proof-of-principle, the ability of this black Nano silica dusting powder to image latent fingerprint is successfully demonstrated and the results show that this fingerprint powder provides clearer fingerprint pattern compared to the commercial one highlighting the potential application of the nanostructured silica in forensic science.

  17. Momentos em freios e em embraiagens

    OpenAIRE

    Mimoso, Rui Miguel Pereira

    2011-01-01

    Dissertação para obtenção do Grau de Mestre em Mestrado Integrado em Engenharia Mecânica Nesta dissertação reúnem-se os modelos de cálculo utilizados na determinação dos momentos em freios e em embraiagens. Neste trabalho consideram-se os casos de freios e embraiagens de atrito seco e atrito viscoso. Nos freios de atrito viscoso são considerados casos em que as características dos fluidos não são induzidas, e outros em que são induzidas modificações a essas mesmas características. São a...

  18. 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...

  19. Parasitic zoonoses: survey in foxes (<em>Vulpes vulpesem> in the northern Apennines / Zoonosi parassitarie: indagini in volpi (<em>Vulpes vulpesem> dell'Appennino settentrionale

    Directory of Open Access Journals (Sweden)

    Vittorio Guberti

    1991-07-01

    Full Text Available Abstract A parasitological survey on 153 foxes was carried out in the northern Apennines, during the period 1984-1987. The following parasites were identified: <em>Toxocara canisem> (46.4%, <em>Taenia> sp. (17%, <em>Uncinaria stenocephalaem> (11.8%, <em>Mesocestoides lineatusem> (11.1%, <em>Ancylostoma caninumem> (3.9%, <em>Taenia hydatigenaem> (3.3%, <em>Trichuris vulpisem> (3.3%, <em>Dipylidium caninumem> (2.6%, <em>Taenia crassicepsem> (2%. All foxes were negative for <em>Trichinella> sp. A statistical analysis was performed to evaluate differences in the parasitic fauna according to the sex and age classes of the hosts. The role that the fox could have as a reservoir of helminthic zoonoses is discussed. The results are compared with those of similar studies carried out in Italy. Riassunto Nel periodo 1984-1987 è stata condotta un'indagine parassitologica su 153 volpi abbattute nell'Appennino romagnolo. Sono stati reperiti i seguenti parassiti: <em>Toxocara canisem> (46,4%, <em>Taenia> sp. (17%, <em>Uncinaria stenocephalaem> (11,8%, <em>Mesocestoides lineatusem> (11,1%, <em>Ancylostoma caninumem> (3,9%, <em>Taenia hydatigenaem> (3,3%, <em>Trichuris vulpisem> (3,3%, <em>Dipylidium caninumem> (2,6%, <em>Taenia crassicepsem> (2%. Tutte le volpi esaminate sono risultate negative per <em>Trichinella> sp. È stata effettuata l'analisi statistica dei dati per evidenziare eventuali differenze della fauna parassitaria in relazione al sesso e all'età delle volpi. Sulla base dei dati ottenuti viene discussa l'importanza che la Volpe può assumere come serbatoio di zoonosi elmintiche. I risultati acquisiti sono inoltre comparati con quelli ottenuti in analoghe ricerche condotte in Italia.

  20. Abstract: Inference and Interval Estimation for Indirect Effects With Latent Variable Models.

    Science.gov (United States)

    Falk, Carl F; Biesanz, Jeremy C

    2011-11-30

    Models specifying indirect effects (or mediation) and structural equation modeling are both popular in the social sciences. Yet relatively little research has compared methods that test for indirect effects among latent variables and provided precise estimates of the effectiveness of different methods. This simulation study provides an extensive comparison of methods for constructing confidence intervals and for making inferences about indirect effects with latent variables. We compared the percentile (PC) bootstrap, bias-corrected (BC) bootstrap, bias-corrected accelerated (BC a ) bootstrap, likelihood-based confidence intervals (Neale & Miller, 1997), partial posterior predictive (Biesanz, Falk, and Savalei, 2010), and joint significance tests based on Wald tests or likelihood ratio tests. All models included three reflective latent variables representing the independent, dependent, and mediating variables. The design included the following fully crossed conditions: (a) sample size: 100, 200, and 500; (b) number of indicators per latent variable: 3 versus 5; (c) reliability per set of indicators: .7 versus .9; (d) and 16 different path combinations for the indirect effect (α = 0, .14, .39, or .59; and β = 0, .14, .39, or .59). Simulations were performed using a WestGrid cluster of 1680 3.06GHz Intel Xeon processors running R and OpenMx. Results based on 1,000 replications per cell and 2,000 resamples per bootstrap method indicated that the BC and BC a bootstrap methods have inflated Type I error rates. Likelihood-based confidence intervals and the PC bootstrap emerged as methods that adequately control Type I error and have good coverage rates.

  1. The effect of DNA recovery on the subsequent quality of latent fingermarks.

    Science.gov (United States)

    Fieldhouse, Sarah; Oravcova, Eliska; Walton-Williams, Laura

    2016-10-01

    The recovery of DNA and fingermark evidence from the same site can be problematic on account of potential contamination from fingermark visualisation techniques, and/or the destructive capability of the DNA recovery method. Forensic investigators are therefore often required to choose which evidence type to recover, or to recover both evidence types from different sites. Research typically documents the effects of fingermark visualisation techniques on the subsequent recovery of DNA, whereas this research has investigated the effects of DNA recovery on the quality of subsequently recovered latent fingermarks. Eccrine rich, sebaceous rich, and 'normal' latent fingermarks were deposited onto five substrates: glass; aluminium; textured plastic; varnished wood; photocopier paper and aged from 4h to 4 weeks. Approximately half of the control fingermarks were developed without DNA recovery on all substrates. The remaining samples were subjected to one of five DNA recovery methods prior to fingermark development. Pre and post DNA recovered fingermarks were graded for quality, and AFIS correlations scores were obtained and analysed for statistically significant differences using Wilcoxon Signed Rank tests and Friedman tests. All of the DNA recovery methods reduced the quality of latent fingermarks on glass surfaces. Flocked swabs and gel lifts were the least destructive DNA recovery methods on the remaining surfaces, except for aluminium sheet metal. The quality of latent fingermarks deposited onto glossed wood and textured plastic and paper were less affected by dry swabbing. Wet swabbing and tape lifting were very damaging methods of DNA recovery. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  2. Explicit estimating equations for semiparametric generalized linear latent variable models

    KAUST Repository

    Ma, Yanyuan

    2010-07-05

    We study generalized linear latent variable models without requiring a distributional assumption of the latent variables. Using a geometric approach, we derive consistent semiparametric estimators. We demonstrate that these models have a property which is similar to that of a sufficient complete statistic, which enables us to simplify the estimating procedure and explicitly to formulate the semiparametric estimating equations. We further show that the explicit estimators have the usual root n consistency and asymptotic normality. We explain the computational implementation of our method and illustrate the numerical performance of the estimators in finite sample situations via extensive simulation studies. The advantage of our estimators over the existing likelihood approach is also shown via numerical comparison. We employ the method to analyse a real data example from economics. © 2010 Royal Statistical Society.

  3. Substrate stiffness promotes latent TGF-β1 activation in hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Pang, Mingshu; Teng, Yao; Huang, Jianyong; Yuan, Yuan; Lin, Feng; Xiong, Chunyang

    2017-01-01

    Hepatocellular carcinoma (HCC) was usually coupled with increased stiffness of the extracellular matrix (ECM) and elevated level of transforming growth factor-β1 (TGF-β1). However, the mechanism by which substrate rigidity modulated TGF-β1 signaling transduction remained unknown. This paper investigated the molecular mechanism of how matrix stiffness regulating TGF-β1 signaling in HCC cells. By means of stiffness tunable collagen I-coated polyacrylamide (PA) gels, we found that the expressions of β1 integrin, p-FAK Y397 and p-Smad2 upregulated on stiffer gels as well as the content of TGF-β1 in culture media of HCC cells, which were inhibited by RGD blocking peptides, Y-27632 (ROCK inhibitor) or Blebbistatin (myosin II inhibitor). Cellular traction force was also significantly higher when plated on stiffer substrates but dramatically decreased after treatment with Y-27632 or Blebbistatin. Furthermore, the upregulation of p-Smad2 in the HCC cells on stiffer PA gels induced by exogenetic latent TGF-β1 was downregulated in the presence of RGD peptides. The nuclear translocation of Smad2 induced by latent TGF-β1 was inhibited by Y-27632 or Blebbistatin. Our results suggested that the extracellular matrix stiffness regulated latent TGF-β1 activation by cytoskeletal tension in HCC cells, showing that matrix stiffness was a key regulator involving the TGF-β1 activity in HCC cells. The current study presented a mechanism of how hepatocirrhosis developed into liver cancer. - Highlights: • TGF-β1 signaling pathway regulated by ECM stiffness was studied in hepatocellular carcinoma. • Matrix stiffness promoted latent TGF-β1 activation via β1 integrin-FAK-Rho GTPase pathway. • A mechanism of how hepatocirrhosis developed into liver cancer was presented.

  4. PROBLEM OF OPTIMAL CONTROL OF EPIDEMIC IN VIEW OF LATENT PERIOD

    Directory of Open Access Journals (Sweden)

    2017-01-01

    Full Text Available The problem of optimal control of epidemic through vaccination and isolation, taking into account latent period is considered. The target function is minimized - functionality summarizing costs on epidemic prevention and treatment and also considering expenses on infected people left at the end of control T who may be a new source of epidemic. On the left endpoint of the integration segment initial data is given - quantity of infected and confirmed people at the moment t, the right endpoint is free. The dynamic constraints are written by way of a system of simple differential equations describing the speed of changes of number of subjected to infection and number of already infected. Besides the inhomogeneous communi- ty is considered, consisting of four age groups (babies, preschool children, school children and adults. The speed of vaccina- tion (number of vaccinated per a time unit and isolation speed are used as the control functions. There are some restrictions on control above and below. The latent period is described by the constant h and is part of the equation describing the con- tamination speed of people as a retarding in argument t, i.e. a person being in a latent period infects others not being aware of his disease. For problem solving Pontryagin maximum principle is used where it can be seen that the control is piecewise constant. The result of numerical implementation of discrete problem of optimal control is given. The conclusions are made that the latent period significantly influence the incidence rate and as consequence the costs on epidemic suppression. The programme based on the programming language Delphi gives an opportunity to estimate the scale of epidemic at different initial data and restrictions on control as well as to find an optimal control minimizing costs on epimedic suppression.

  5. Realist identification of group-level latent variables for perinatal social epidemiology theory building.

    Science.gov (United States)

    Eastwood, John Graeme; Jalaludin, Bin Badrudin; Kemp, Lynn Ann; Phung, Hai Ngoc

    2014-01-01

    We have previously reported in this journal on an ecological study of perinatal depressive symptoms in South Western Sydney. In that article, we briefly reported on a factor analysis that was utilized to identify empirical indicators for analysis. In this article, we report on the mixed method approach that was used to identify those latent variables. Social epidemiology has been slow to embrace a latent variable approach to the study of social, political, economic, and cultural structures and mechanisms, partly for philosophical reasons. Critical realist ontology and epistemology have been advocated as an appropriate methodological approach to both theory building and theory testing in the health sciences. We describe here an emergent mixed method approach that uses qualitative methods to identify latent constructs followed by factor analysis using empirical indicators chosen to measure identified qualitative codes. Comparative analysis of the findings is reported together with a limited description of realist approaches to abstract reasoning.

  6. A latent transition analysis of bullying and victimization in Chinese primary school students.

    Directory of Open Access Journals (Sweden)

    Yiqin Pan

    Full Text Available Bullying is a social phenomenon that impacts a large number of children and young people, worldwide. This study aimed to longitudinally examine the development of bullying and victimization in Chinese students in grades 4, 5, and 6. We used latent class analysis to empirically identify groups of youth with different bullying and victimization patterns, and then used latent transition analysis to explore the movement of children between these latent classes over time. Results showed that: (1 across the three time points, students could be classified into four classes: bullies, victims, bully-victims, and non-involved children; and (2 students in the non-involved class tended to remain in that class when moving to higher grades, students in the bully and victims classes tended to transition to the non-involved class, while students in the bully-victims class tended to transition to the bullies class. Thus, future intervention should be implemented to prevent bully-victims from bullying behaviors.

  7. STRUCTURE RELATION OF VIOLENCE AND PERSONALITY LATENT DIMENSIONS OF PREADOLESCENT BASKETBALL PLAYERS

    Directory of Open Access Journals (Sweden)

    Miroljub Ivanović

    2012-09-01

    Full Text Available The aim of this research was to define structure relations of latent dimension violence among peers structure, characteristics and parent’s educational attitudes. In this research participated 134 basketball players (mini-jam, younger pioneers and pioneers. The research was conducted using the PRONA questionnaire for peers violence evaluation (Maksimovic and collaborators, 2008. Analysing the main components space of peers’ violence, three main components have been determined as dangerous behaviour exposure, announced victim and physiological violence. Mutual relation of these latent personality characteristics examinees dimensions and educational attitudes of their parents has been determined using the Pirson’s correlation coefficien.

  8. <em>In Vivoem> Histamine Optical Nanosensors

    Directory of Open Access Journals (Sweden)

    Heather A. Clark

    2012-08-01

    Full Text Available In this communication we discuss the development of ionophore based nanosensors for the detection and monitoring of histamine levels <em>in vivoem>. This approach is based on the use of an amine-reactive, broad spectrum ionophore which is capable of recognizing and binding to histamine. We pair this ionophore with our already established nanosensor platform, and demonstrate <em>in vitroem> and <em>in vivoem> monitoring of histamine levels. This approach enables capturing rapid kinetics of histamine after injection, which are more difficult to measure with standard approaches such as blood sampling, especially on small research models. The coupling together of <em>in vivoem> nanosensors with ionophores such as nonactin provide a way to generate nanosensors for novel targets without the difficult process of designing and synthesizing novel ionophores.

  9. Symptom Cluster Research With Biomarkers and Genetics Using Latent Class Analysis.

    Science.gov (United States)

    Conley, Samantha

    2017-12-01

    The purpose of this article is to provide an overview of latent class analysis (LCA) and examples from symptom cluster research that includes biomarkers and genetics. A review of LCA with genetics and biomarkers was conducted using Medline, Embase, PubMed, and Google Scholar. LCA is a robust latent variable model used to cluster categorical data and allows for the determination of empirically determined symptom clusters. Researchers should consider using LCA to link empirically determined symptom clusters to biomarkers and genetics to better understand the underlying etiology of symptom clusters. The full potential of LCA in symptom cluster research has not yet been realized because it has been used in limited populations, and researchers have explored limited biologic pathways.

  10. Scintigraphy in detection of latent inflammatory foci in patients with pseudarthroses

    International Nuclear Information System (INIS)

    Woy-Wojciechowski, J.; Zawadzinski, S.

    1982-01-01

    Treatment of infected pseudarthroses is one of the most difficult problems in orthopaedic surgery. Presence of latent inflammatory foci may be a serious complication after bone grafting. In 14 cases of pseudarthroses radioisotope scanning demonstrated in 5 cases presence of additional latent inflammatory foci which gave cues as to the type and extent of surgical treatment. In all these cases evaluation of the local condition by X-ray examination was insufficient. Isotope scanning was useful for a radical surgical treatment making possible complete eradication of the inflammation and reducing thus the risk of inflammation recurrence at the site of the operation performed for achieving bone union or for implanting bone graft. (author)

  11. Mode choice models' ability to express intention to change travel behaviour considering non-compensatory rules and latent variables

    Directory of Open Access Journals (Sweden)

    Nobuhiro Sanko

    2013-03-01

    Full Text Available Disaggregate behaviour choice models have been improved in many aspects, but they are rarely evaluated from the viewpoint of their ability to express intention to change travel behaviour. This study compared various models, including objective and latent models and compensatory and non-compensatory decision-making models. Latent models contain latent factors calculated using the LISREL (linear structural relations model. Non-compensatory models are based on a lexicographic-semiorder heuristic. This paper proposes ‘probability increment’ and ‘joint probability increment’ as indicators for evaluating the ability of these models to express intention to change travel behaviour. The application to commuting travel data in the Chukyo metropolitan area in Japan showed that the appropriate non-compensatory and latent models outperform other models.

  12. Variabilità morfologica ed ecologica in <em>Neomys fodiensem> e <em>Neomys anomalusem> nell'Appennino settentrionale

    Directory of Open Access Journals (Sweden)

    Dino Scaravelli

    2003-10-01

    Full Text Available I due <em>Neomys> italiani sono ancora da chiarire dal punto di vista della loro caratterizzazione morfologica e ecologica. Il lavoro prende in considerazione un campione di entrambe le specie proveniente da habitat forestali dell?Appennino settentrionale per i quali sono stati identificati i principali parametri ambientali. Vengono quindi descritte la variabilità dei tratti morfologici delle due specie in aree localizzate nel Parco Nazionale Foreste Casentinesi, Monte Falterona e Campigna nell?Appennino tosco-romagnolo. Risultano di sicuro effetto discriminatorio la maschera facciale, il rapporto piede posteriore/coda e i caratteri cranici. Sulla base dei criteri identificativi si sono realizzate rilevazioni di misure corporee per le due specie e una comparazione degli habitat utilizzati. <em>N. fodiensem> appare unica specie nelle faggete-abetine e dominante nei castagneti, mentre nell?Ontaneta e nelle zone aperte e termofile si registra la sola presenza di <em>N. anomalusem>. Mancano entrambi nei prati cespugliati, nella pecceta e nella cerreta. I gradienti presenti sono quindi illustrati. Non appare una differenza altitudinale nel campione esaminato, posto in stazioni tra i 400 e i 1300 m, ma per entrambe vi sono maggiori riscontri nella fascia tra 700 e 850 m. Nell?analisi multivariata rispetto alle altre specie e alle variabili ambientali si riscontra sempre una discreta correlazione con la presenza di acqua di una certa ampiezza, che comunque è significativa solo per <em>N. fodiensem>, mentre risulta di interesse la positiva correlazione di <em>N. anomalusem> con <em>Apodemus sylvaticusem>.

  13. Latent constructs of the autobiographical memory questionnaire: a recollection-belief model of autobiographical experience.

    Science.gov (United States)

    Fitzgerald, Joseph M; Broadbridge, Carissa L

    2013-01-01

    Many researchers employ single-item scales of subjective experiences such as imagery and confidence to assess autobiographical memory. We tested the hypothesis that four latent constructs, recollection, belief, impact, and rehearsal, account for the variance in commonly used scales across four different types of autobiographical memory: earliest childhood memory, cue word memory of personal experience, highly vivid memory, and most stressful memory. Participants rated each memory on scales hypothesised to be indicators of one of four latent constructs. Multi-group confirmatory factor analyses and structural analyses confirmed the similarity of the latent constructs of recollection, belief, impact, and rehearsal, as well as the similarity of the structural relationships among those constructs across memory type. The observed pattern of mean differences between the varieties of autobiographical experiences was consistent with prior research and theory in the study of autobiographical memory.

  14. Echolocation calls and morphology in the Mehelyi’s (<em>Rhinolophus mehelyiem> and mediterranean (<em>R. euryaleem> horseshoe bats: implications for resource partitioning

    Directory of Open Access Journals (Sweden)

    Egoitz Salsamendi

    2006-03-01

    Full Text Available Abstract <em>Rhinolophus euryaleem> and <em>R. mehelyiem> are morphologically very similar species and their distributions overlap extensively in the Mediterranean basin. We modelled their foraging behaviour using echolocation calls and wing morphology and, assuming niche segregation occurs between the two species, we explored how it is shaped by these factors. Resting frequency of echolocation calls was recorded and weight, forearm length, wing loading, aspect ratio and wing tip shape index were measured. <em>R. mehelyiem> showed a significantly higher resting frequency than <em>R. euryaleem>, but differences are deemed insufficient for dietary niche segregation. Weight and forearm length were significantly larger in <em>R. mehelyiem>. The higher values of aspect ratio and wing loading and a lower value of wing tip shape index in <em>R. melehyiem> restrict its flight manoeuvrability and agility. Therefore, the flight ability of <em>R. mehelyiem> may decrease as habitat complexity increases. Thus, the principal mechanism for resource partitioning seems to be based on differing habitat use arising from differences in wing morphology. Riassunto Ecolocalizzazione e morfologia nei rinolofi di Mehely (<em>Rhinolophus mehelyiem> e euriale (<em>R. euryaleem>: implicazioni nella segregazione delle risorse trofiche. <em>Rhinolophus euryaleem> e <em>R. mehelyiem> sono specie morfologicamente molto simili, la cui distribuzione risulta largamente coincidente in area mediterranea. Il comportamento di foraggiamento delle due specie è stato analizzato in funzione delle caratteristiche dei segnali di ecolocalizzazione e della morfologia alare, ed è stata valutata l’incidenza di questi fattori nell’ipotesi di una segregazione delle nicchie. È stata rilevata la frequenza a riposo dei segnali ultrasonori, così come il peso, la lunghezza dell’avambraccio, il carico alare, e due

  15. Partial Granger causality--eliminating exogenous inputs and latent variables.

    Science.gov (United States)

    Guo, Shuixia; Seth, Anil K; Kendrick, Keith M; Zhou, Cong; Feng, Jianfeng

    2008-07-15

    Attempts to identify causal interactions in multivariable biological time series (e.g., gene data, protein data, physiological data) can be undermined by the confounding influence of environmental (exogenous) inputs. Compounding this problem, we are commonly only able to record a subset of all related variables in a system. These recorded variables are likely to be influenced by unrecorded (latent) variables. To address this problem, we introduce a novel variant of a widely used statistical measure of causality--Granger causality--that is inspired by the definition of partial correlation. Our 'partial Granger causality' measure is extensively tested with toy models, both linear and nonlinear, and is applied to experimental data: in vivo multielectrode array (MEA) local field potentials (LFPs) recorded from the inferotemporal cortex of sheep. Our results demonstrate that partial Granger causality can reveal the underlying interactions among elements in a network in the presence of exogenous inputs and latent variables in many cases where the existing conditional Granger causality fails.

  16. Measurement Uncertainty in Racial and Ethnic Identification among Adolescents of Mixed Ancestry: A Latent Variable Approach

    Science.gov (United States)

    Tracy, Allison J.; Erkut, Sumru; Porche, Michelle V.; Kim, Jo; Charmaraman, Linda; Grossman, Jennifer M.; Ceder, Ineke; Garcia, Heidie Vazquez

    2010-01-01

    In this article, we operationalize identification of mixed racial and ethnic ancestry among adolescents as a latent variable to (a) account for measurement uncertainty, and (b) compare alternative wording formats for racial and ethnic self-categorization in surveys. Two latent variable models were fit to multiple mixed-ancestry indicator data from…

  17. Phytochemical Composition, Antioxidant and Xanthine Oxidase Inhibitory Activities of <em>Amaranthus cruentusem> L. and <em>Amaranthus hybridusem> L. Extracts

    Directory of Open Access Journals (Sweden)

    Jeanne F. Millogo

    2012-06-01

    Full Text Available This paper describes a preliminary assessment of the nutraceutical value of <em>Amaranthus cruentus (A. cruentusem> and <em>Amaranthus hybridus (A. hybridusem>, two food plant species found in Burkina Faso. Hydroacetonic (HAE, methanolic (ME, and aqueous extracts (AE from the aerial parts were screened for <em>in vitroem> antioxidant and xanthine oxidase inhibitory activities. Phytochemical analyses revealed the presence of polyphenols, tannins, flavonoids, steroids, terpenoids, saponins and betalains. Hydroacetonic extracts have shown the most diversity for secondary metabolites. The TLC analyses of flavonoids from HAE extracts showed the presence of rutin and other unidentified compounds. The phenolic compound contents of the HAE, ME and AE extracts were determined using the Folin–Ciocalteu method and ranged from 7.55 to 10.18 mg Gallic acid equivalent GAE/100 mg. Tannins, flavonoids, and flavonols ranged from 2.83 to 10.17 mg tannic acid equivalent (TAE/100 mg, 0.37 to 7.06 mg quercetin equivalent (QE /100 mg, and 0.09 to 1.31 mg QE/100 mg, respectively. The betacyanin contents were 40.42 and 6.35 mg Amaranthin Equivalent/100 g aerial parts (dry weight in <em>A. cruentusem> and <em>A. hybridusem>, respectively. Free-radical scavenging activity expressed as IC50 (DPPH method and iron reducing power (FRAP method ranged from 56 to 423 µg/mL and from 2.26 to 2.56 mmol AAE/g, respectively. Xanthine oxidase inhibitory activities of extracts of <em>A. cruentus em>and <em>A. hybridusem> were 3.18% and 38.22%, respectively.<em> em>The> A. hybridusem> extract showed the best antioxidant and xanthine oxidase inhibition activities. The results indicated that the phytochemical contents of the two species justify their traditional uses as nutraceutical food plants.

  18. Dermatoses em renais cronicos em terapia dialitica

    Directory of Open Access Journals (Sweden)

    Luis Alberto Batista Peres

    2014-03-01

    Full Text Available Objetivo: As desordens cutâneas e das mucosas são comuns em pacientes em hemodiálise a longo prazo. A diálise prolonga a expectativa de vida, dando tempo para a manifestação destas anormalidades. Os objetivos deste estudo foram avaliar a prevalência de problemas dermatológicos em pacientes com doença renal crônica (DRC em hemodiálise. Métodos: Cento e quarenta e cinco pacientes com doença renal crônica em hemodiálise foram estudados. Todos os pacientes foram completamente analisados para as alterações cutâneas, de cabelos, mucosas e unhas por um único examinador e foram coletados dados de exames laboratoriais. Os dados foram armazenados em um banco de dados do Microsolft Excel e analisados por estatística descritiva. As variáveis contínuas foram comparadas pelo teste t de Student e as variáveis categóricas utilizando o teste do qui-quadrado ou o teste Exato de Fischer, conforme adequado. Resultados: O estudo incluiu 145 pacientes, com idade média de 53,6 ± 14,7 anos, predominantemente do sexo masculino (64,1% e caucasianos (90,0%. O tempo médio de diálise foi de 43,3 ± 42,3 meses. As principais doenças subjacentes foram: hipertensão arterial em 33,8%, diabetes mellitus em 29,6% e glomerulonefrite crônica em 13,1%. As principais manifestações dermatológicas observadas foram: xerose em 109 (75,2%, equimose em 87 (60,0%, prurido em 78 (53,8% e lentigo em 33 (22,8% pacientes. Conclusão: O nosso estudo mostrou a presença de mais do que uma dermatose por paciente. As alterações cutâneas são frequentes em pacientes em diálise. Mais estudos são necessários para melhor caracterização e manejo destas dermatoses.

  19. Cytotoxicity and Glycan-Binding Properties of an 18 kDa Lectin Isolated from the Marine Sponge <em>Halichondria em>okadai>

    Directory of Open Access Journals (Sweden)

    Yasuhiro Ozeki

    2012-04-01

    Full Text Available A divalent cation-independent lectin—HOL-18, with cytotoxic activity against leukemia cells, was purified from a demosponge, <em>Halichondria okadaiem>. HOL-18 is a 72 kDa tetrameric lectin that consists of four non-covalently bonded 18 kDa subunits. Hemagglutination activity of the lectin was strongly inhibited by chitotriose (GlcNAcβ1-4GlcNAcβ1-4GlcNAc, fetuin and mucins from porcine stomach and bovine submaxillary gland. Lectin activity was stable at pH 4–12 and temperatures lower than 60 °C. Frontal affinity chromatography with 16 types of pyridylaminated oligosaccharides indicated that the lectin had an affinity for <em>N>-linked complex-type and sphingolipid-type oligosaccharides with <em>N>-acetylated hexosamines and neuramic acid at the non-reducing termini. The lectin killed Jurkat leukemia T cells and K562 erythroleukemia cells in a dose- and carbohydrate-dependent manner.

  20. Latent myostatin has significant activity and this activity is controlled more efficiently by WFIKKN1 than by WFIKKN2

    OpenAIRE

    Szláma, György; Trexler, Mária; Patthy, László

    2013-01-01

    Myostatin, a negative regulator of skeletal muscle growth, is produced from myostatin precursor by multiple steps of proteolytic processing. After cleavage by a furin-type protease, the propeptide and growth factor domains remain associated, forming a noncovalent complex, the latent myostatin complex. Mature myostatin is liberated from latent myostatin by bone morphogenetic protein 1/tolloid proteases. Here, we show that, in reporter assays, latent myostatin preparations have significant myos...

  1. National policies on the management of latent tuberculosis infection: review of 98 countries

    Science.gov (United States)

    Jagger, Ann; Reiter-karam, Silke; Getahun, Haileyesus

    2018-01-01

    Abstract Objective To review policies on management of latent tuberculosis infection in countries with low and high burdens of tuberculosis. Methods We divided countries reporting data to the World Health Organization (WHO) Global Tuberculosis Programme into low and high tuberculosis burden, based on WHO criteria. We identified national policy documents on management of latent tuberculosis through online searches, government websites, WHO country offices and personal communication with programme managers. We made a descriptive analysis with a focus on policy gaps and deviations from WHO policy recommendations. Findings We obtained documents from 68 of 113 low-burden countries and 30 of 35 countries with the highest burdens of tuberculosis or human immunodeficiency virus (HIV)-associated tuberculosis. Screening and treatment of latent tuberculosis infection in people living with HIV was recommended in guidelines of 29 (96.7%) high-burden and 54 (79.7%) low-burden countries. Screening for children aged countries. In most high-burden countries the recommendation was symptom screening alone before treatment, whereas in all low-burden countries it was testing before treatment. Some low-burden countries’ policies did not comply with WHO recommendations: nine (13.2%) recommended tuberculosis preventive treatment for travellers to high-burden countries and 10 (14.7%) for patients undergoing abdominal surgery. Conclusion Lack of solid evidence on certain aspects of management of latent tuberculosis infection results in national policies which vary considerably. This highlights a need to advance research and develop clear, implementable and evidence-based WHO policies. PMID:29531416

  2. Latent structure and construct validity of the reinforcement sensitivity questionnaire

    Directory of Open Access Journals (Sweden)

    Mitrović Dušanka

    2008-01-01

    Full Text Available The Revised reinforcement sensitivity theory contains three basic systems: Behavioral inhibition system (BAS, Behavioral activation system (BIS and the Fight/ Flight/ Freeze (FFF system. In this model, BIS is a system for detection of potential conflict or threat, and FFFS differs three basic patterns of reaction to actual or perceived danger. In Study 1, which was aimed at the examination of the latent structure of the RSQ, was conducted on a sample of 472 participants of both genders. The best - fitting model suggests that, at the top level of hierarchy, three dimensions exist, which are analogous to the BIS, BAS and FFF. The last dimension contains three subordinate dimensions, which represent the subsystems of the FFF. Study 2, in which 203 subjects participated, was aimed at examination of the relations between the dimensions of the Revised reinforcement sensitivity theory and dimensions of the PEN model. Confirmatory factor analyses of the RSQ and EPQ-R dimensions revealed that the best-fitting model comprised three latent dimensions, the first one being analogous to the BIS - Neuroticism, the second one to the BAS - Extraversion, and the third to the Aggressiveness- Psychoticism. The structure of the latent dimensions is in accordance with the expectations. The results state that fear and anxiety (which neurophysiological distinction is emphasized by Gray, are substantively similar on the behavioral level. Also, the results suggest that the Freeze dimension is probably closer to the BIS system than to the FFF.

  3. Over-Expression of CYP2E1 mRNA and Protein: Implications of Xenobiotic Induced Damage in Patients with <em>De Novoem> Acute Myeloid Leukemia with inv(16(p13.1q22; <em>CBFβ>-MYH11em>

    Directory of Open Access Journals (Sweden)

    Carlos E. Bueso-Ramos

    2012-08-01

    Full Text Available Environmental exposure to benzene occurs through cigarette smoke, unleaded gasoline and certain types of plastic. Benzene is converted to hematotoxic metabolites by the hepatic phase-I enzyme CYP2E1, and these metabolites are detoxified by the phase-II enzyme NQO1. The genes encoding these enzymes are highly polymorphic and studies of these polymorphisms have shown different pathogenic and prognostic features in various hematological malignancies. The potential role of different cytochrome p450 metabolizing enzymes in the pathogenesis of acute myeloid leukemia (AML in an area of active interest. In this study, we demonstrate aberrant CYP2E1 mRNA over-expression by quantitative real-time polymerase chain reaction in 11 cases of <em>de novoem> AML with inv(16; CBFβ-MYH11. CYP2E1 mRNA levels correlated with <em>CBFβ>-MYH11 em>transcript levels and with bone marrow blast counts in all cases. CYP2E1 over-expression correlated positively with NQO1 mRNA levels (R2 = 0.934, n = 7. By immunohistochemistry, CYP2E1 protein was more frequently expressed in AML with inv(16 compared with other types of AML (<em>p> < 0.001. We obtained serial bone marrow samples from two patients with AML with inv(16 before and after treatment. CYP2E1 mRNA expression levels decreased in parallel with <em>CBFβ>-MYH11 em>transcript levels and blast counts following chemotherapy. In contrast, CYP1A2 transcript levels did not change in either patient. This is the first study to demonstrate concurrent over-expression of CYP2E1 and NQO1 mRNA in AML with inv(16. These findings also suggest that a balance between CYP2E1 and NQO1 may be important in the pathogenesis of AML with inv(16.

  4. Latent fingermark development using low-vacuum vaporization of ninhydrin.

    Science.gov (United States)

    Chen, Chun-Chieh; Yang, Chao-Kai; Liao, Jeh-Shane; Wang, Sheng-Meng

    2015-12-01

    The vacuum technique is a method of vaporizing a solid material to its gas phase, helping deposit reagents gently on target surfaces to develop latent fingermarks. However, this application is rarely reported in the literature. In this study, a homemade fume hood with a built-in vacuum control system and programmable heating system designed by the Taiwan Criminal Investigation Bureau is introduced. Factors that affect the instrument's performance in developing fingermarks are discussed, including the quantity of chemicals for vaporization, heating program arrangement, and paper of different materials. The results show that fingermarks are effectively developed by vaporizing solid ninhydrin. This would be an alternative application in selecting a solvent-free method for protecting the environment and reducing health hazards in the lab. In terms of the heating program, the result indicates that under a low-vacuum condition (50 mTorr), 80-90 °C is a suitable temperature range for ninhydrin vaporization, allowing ninhydrin to be vaporized without bumping and waste. In terms of the performance on different material papers, this instrument demonstrates its capacity by developing latent fingermarks on thermal paper without discoloration or damaging the original writing, and the same results are also observed on Taiwan and United States banknotes. However, a coherent result could be hardly obtained using the same vaporization setting because different banknotes have their own surface features and water absorption ability or other unique factors may influence the effect of ninhydrin deposition. This study provides a reliable application for developing latent fingermarks without using solvents, and it is also expected to contribute to environmental protection along with the trend of green chemistry technology. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  5. Dissociative Experiences are Associated with Obsessive-Compulsive Symptoms in a Non-clinical Sample: A Latent Profile Analysis

    Science.gov (United States)

    BOYSAN, Murat

    2014-01-01

    Introduction There has been a burgeoning literature considering the significant associations between obsessive-compulsive symptoms and dissociative experiences. In this study, the relationsips between dissociative symtomotology and dimensions of obsessive-compulsive symptoms were examined in homogeneous sub-groups obtained with latent class algorithm in an undergraduate Turkish sample. Method Latent profile analysis, a recently developed classification method based on latent class analysis, was applied to the Dissociative Experiences Scale (DES) item-response data from 2976 undergraduates. Differences in severity of obsessive-compulsive symptoms, anxiety and depression across groups were evaluated by running multinomial logistic regression analyses. Associations between latent class probabilities and psychological variables in terms of obsessive-compulsive sub-types, anxiety, and depression were assessed by computing Pearson’s product-moment correlation coefficients. Results The findings of the latent profile analysis supported further evidence for discontinuity model of dissociative experiences. The analysis empirically justified the distinction among three sub-groups based on the DES items. A marked proportion of the sample (42%) was assigned to the high dissociative class. In the further analyses, all sub-types of obsessive-compulsive symptoms significantly differed across latent classes. Regarding the relationships between obsessive-compulsive symptoms and dissociative symptomatology, low dissociation appeared to be a buffering factor dealing with obsessive-compulsive symptoms; whereas high dissociation appeared to be significantly associated with high levels of obsessive-compulsive symptoms. Conclusion It is concluded that the concept of dissociation can be best understood in a typological approach that dissociative symptomatology not only exacerbates obsessive-compulsive symptoms but also serves as an adaptive coping mechanism. PMID:28360635

  6. Epstein-Barr Virus: The Path from Latent to Productive Infection.

    Science.gov (United States)

    Chiu, Ya-Fang; Sugden, Bill

    2016-09-29

    The intrinsic properties of different viruses have driven their study. For example, the capacity for efficient productive infection of cultured cells by herpes simplex virus 1 has made it a paradigm for this mode of infection for herpesviruses in general. Epstein-Barr virus, another herpesvirus, has two properties that have driven its study: It causes human cancers, and it exhibits a tractable transition from its latent to its productive cycle in cell culture. Here, we review our understanding of the path Epstein-Barr virus follows to move from a latent infection to and through its productive cycle. We use information from human infections to provide a framework for describing studies in cell culture and, where possible, the molecular resolutions from these studies. We also pose questions whose answers we think are pivotal to understanding this path, and we provide answers where we can.

  7. Noves tècniques per a la detecció de la tuberculosi latent

    OpenAIRE

    Rivas, Inmaculada

    2010-01-01

    Espanya és un dels països industrialitzats amb major índex de tuberculosi, especialment entre els afectats pel VIH i les persones drogodependents, però la infecció acostuma a romandre latent en la majoria dels casos. La prova in vivo tradicional, coneguda com a PPD, consisteix en un test cutani que pot donar falsos positius o falsos negatius. Aquest estudi ha diagnosticat tuberculosi latent gràcies a dos nous mètodes in vitro, entre la població drogodependent de l'àrea metropolitana de Barcel...

  8. Pathways of early fatherhood, marriage, and employment: a latent class growth analysis.

    Science.gov (United States)

    Dariotis, Jacinda K; Pleck, Joseph H; Astone, Nan M; Sonenstein, Freya L

    2011-05-01

    In the National Longitudinal Survey of Youth 1979 (NLSY79), young fathers include heterogeneous subgroups with varying early life pathways in terms of fatherhood timing, the timing of first marriage, and holding full-time employment. Using latent class growth analysis with 10 observations between ages 18 and 37, we derived five latent classes with median ages of first fatherhood below the cohort median (26.4), constituting distinct early fatherhood pathways representing 32.4% of NLSY men: (A) Young Married Fathers, (B) Teen Married Fathers, (C) Young Underemployed Married Fathers, (D) Young Underemployed Single Fathers, and (E) Young Later-Marrying Fathers. A sixth latent class of men who become fathers around the cohort median, following full-time employment and marriage (On-Time On-Sequence Fathers), is the comparison group. With sociodemographic background controlled, all early fatherhood pathways show disadvantage in at least some later-life circumstances (earnings, educational attainment, marital status, and incarceration). The extent of disadvantage is greater when early fatherhood occurs at relatively younger ages (before age 20), occurs outside marriage, or occurs outside full-time employment. The relative disadvantage associated with early fatherhood, unlike early motherhood, increases over the life course.

  9. A comparative study of matrix metalloproteinase and aggrecanase mediated release of latent cytokines at arthritic joints.

    Science.gov (United States)

    Mullen, Lisa; Adams, Gill; Foster, Julie; Vessillier, Sandrine; Köster, Mario; Hauser, Hansjörg; Layward, Lorna; Gould, David; Chernajovsky, Yuti

    2014-09-01

    Latent cytokines are engineered by fusing the latency associated peptide (LAP) derived from transforming growth factor-β (TGF-β) with the therapeutic cytokine, in this case interferon-β (IFN-β), via an inflammation-specific matrix metalloproteinase (MMP) cleavage site. To demonstrate latency and specific delivery in vivo and to compare therapeutic efficacy of aggrecanase-mediated release of latent IFN-β in arthritic joints to the original MMP-specific release. Recombinant fusion proteins with MMP, aggrecanase or devoid of cleavage site were expressed in CHO cells, purified and characterised in vitro by Western blotting and anti-viral protection assays. Therapeutic efficacy and half-life were assessed in vivo using the mouse collagen-induced arthritis model (CIA) of rheumatoid arthritis and a model of acute paw inflammation, respectively. Transgenic mice with an IFN-regulated luciferase gene were used to assess latency in vivo and targeted delivery to sites of disease. Efficient localised delivery of IFN-β to inflamed paws, with low levels of systemic delivery, was demonstrated in transgenic mice using latent IFN-β. Engineering of latent IFN-β with an aggrecanase-sensitive cleavage site resulted in efficient cleavage by ADAMTS-4, ADAMTS-5 and synovial fluid from arthritic patients, with an extended half-life similar to the MMP-specific molecule and greater therapeutic efficacy in the CIA model. Latent cytokines require cleavage in vivo for therapeutic efficacy, and they are delivered in a dose dependent fashion only to arthritic joints. The aggrecanase-specific cleavage site is a viable alternative to the MMP cleavage site for the targeting of latent cytokines to arthritic joints. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  10. Assessing Factors Related to Waist Circumference and Obesity: Application of a Latent Variable Model

    OpenAIRE

    Dalvand, Sahar; Koohpayehzadeh, Jalil; Karimlou, Masoud; Asgari, Fereshteh; Rafei, Ali; Seifi, Behjat; Niksima, Seyed Hassan; Bakhshi, Enayatollah

    2015-01-01

    Background. Because the use of BMI (Body Mass Index) alone as a measure of adiposity has been criticized, in the present study our aim was to fit a latent variable model to simultaneously examine the factors that affect waist circumference (continuous outcome) and obesity (binary outcome) among Iranian adults. Methods. Data included 18,990 Iranian individuals aged 20–65 years that are derived from the third National Survey of Noncommunicable Diseases Risk Factors in Iran. Using latent variabl...

  11. Patient safety in the operating room: an intervention study on latent risk factors

    Directory of Open Access Journals (Sweden)

    van Beuzekom Martie

    2012-06-01

    Full Text Available Abstract Background Patient safety is one of the greatest challenges in healthcare. In the operating room errors are frequent and often consequential. This article describes an approach to a successful implementation of a patient safety program in the operating room, focussing on latent risk factors that influence patient safety. We performed an intervention to improve these latent risk factors (LRFs and increase awareness of patient safety issues amongst OR staff. Methods Latent risk factors were studied using a validated questionnaire applied to the OR staff before and after an intervention. A pre-test/post-test control group design with repeated measures was used to evaluate the effects of the interventions. The staff from one operating room of an university hospital acted as the intervention group. Controls consisted of the staff of the operating room in another university hospital. The outcomes were the changes in LRF scores, perceived incident rate, and changes in incident reports between pre- and post-intervention. Results Based on pre-test scores and participants’ key concerns about organizational factors affecting patient safety in their department the intervention focused on the following LRFs: Material Resources, Training and Staffing Recourses. After the intervention, the intervention operating room - compared to the control operating room - reported significantly fewer problems on Material Resources and Staffing Resources and a significantly lower score on perceived incident rate. The contribution of technical factors to incident causation decreased significantly in the intervention group after the intervention. Conclusion The change of state of latent risk factors can be measured using a patient safety questionnaire aimed at these factors. The change of the relevant risk factors (Material and Staffing resources concurred with a decrease in perceived and reported incident rates in the relevant categories. We conclude that

  12. 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…

  13. Latent hardening size effect in small-scale plasticity

    Science.gov (United States)

    Bardella, Lorenzo; Segurado, Javier; Panteghini, Andrea; Llorca, Javier

    2013-07-01

    We aim at understanding the multislip behaviour of metals subject to irreversible deformations at small-scales. By focusing on the simple shear of a constrained single-crystal strip, we show that discrete Dislocation Dynamics (DD) simulations predict a strong latent hardening size effect, with smaller being stronger in the range [1.5 µm, 6 µm] for the strip height. We attempt to represent the DD pseudo-experimental results by developing a flow theory of Strain Gradient Crystal Plasticity (SGCP), involving both energetic and dissipative higher-order terms and, as a main novelty, a strain gradient extension of the conventional latent hardening. In order to discuss the capability of the SGCP theory proposed, we implement it into a Finite Element (FE) code and set its material parameters on the basis of the DD results. The SGCP FE code is specifically developed for the boundary value problem under study so that we can implement a fully implicit (Backward Euler) consistent algorithm. Special emphasis is placed on the discussion of the role of the material length scales involved in the SGCP model, from both the mechanical and numerical points of view.

  14. Latent hardening size effect in small-scale plasticity

    International Nuclear Information System (INIS)

    Bardella, Lorenzo; Panteghini, Andrea; Segurado, Javier; Llorca, Javier

    2013-01-01

    We aim at understanding the multislip behaviour of metals subject to irreversible deformations at small-scales. By focusing on the simple shear of a constrained single-crystal strip, we show that discrete Dislocation Dynamics (DD) simulations predict a strong latent hardening size effect, with smaller being stronger in the range [1.5 µm, 6 µm] for the strip height. We attempt to represent the DD pseudo-experimental results by developing a flow theory of Strain Gradient Crystal Plasticity (SGCP), involving both energetic and dissipative higher-order terms and, as a main novelty, a strain gradient extension of the conventional latent hardening. In order to discuss the capability of the SGCP theory proposed, we implement it into a Finite Element (FE) code and set its material parameters on the basis of the DD results. The SGCP FE code is specifically developed for the boundary value problem under study so that we can implement a fully implicit (Backward Euler) consistent algorithm. Special emphasis is placed on the discussion of the role of the material length scales involved in the SGCP model, from both the mechanical and numerical points of view. (paper)

  15. Surface latent heat flux as an earthquake precursor

    Directory of Open Access Journals (Sweden)

    S. Dey

    2003-01-01

    Full Text Available The analysis of surface latent heat flux (SLHF from the epicentral regions of five recent earthquakes that occurred in close proximity to the oceans has been found to show anomalous behavior. The maximum increase of SLHF is found 2–7 days prior to the main earthquake event. This increase is likely due to an ocean-land-atmosphere interaction. The increase of SLHF prior to the main earthquake event is attributed to the increase in infrared thermal (IR temperature in the epicentral and surrounding region. The anomalous increase in SLHF shows great potential in providing early warning of a disastrous earthquake, provided that there is a better understanding of the background noise due to the tides and monsoon in surface latent heat flux. Efforts have been made to understand the level of background noise in the epicentral regions of the five earthquakes considered in the present paper. A comparison of SLHF from the epicentral regions over the coastal earthquakes and the earthquakes that occurred far away from the coast has been made and it has been found that the anomalous behavior of SLHF prior to the main earthquake event is only associated with the coastal earthquakes.

  16. Biomecânica de quatro técnicas de fixação da fratura em quatro partes da cabeça umeral Biomechanics of four techniques for fixation of the four-part humeral head fracture

    Directory of Open Access Journals (Sweden)

    Elpídio da Graça

    2013-02-01

    Full Text Available OBJETIVO: Realizar um estudo biomecânico de quatro técnicas de fixação das fraturas em quatro partes da cabeça umeral. MÉTODOS: A fratura foi reproduzida em 40 úmeros plásticos, divididos em grupos de dez conforme a técnica de fixação, cada uma delas empregando diferentes recursos de fixação, em configurações distintas. Os modelos umerais foram montados em uma escápula de alumínio, com tiras de couro mimetizando os tendões do capuz rotador, e submetidos a ensaios de encurvamento e de torção em uma máquina universal de ensaios, usando a rigidez relativa como parâmetro de avaliação. Montagens com o úmero intacto foram analisadas para comparação. RESULTADOS: O comportamento biomecânico das técnicas de fixação variou dentro de uma ampla faixa, as montagens incluindo a placa DCP e os parafusos de 4,5mm de diâmetro sendo significantemente mais rígidos do que as montagens com os fios de Kirschner e os parafusos 3,5 mm de diâmetro. CONCLUSÃO: As quatro técnicas foram capazes de suportar cargas compatíveis com a demanda fisiológica, mas aquelas com a maior rigidez relativa devem ser as preferidas para finalidades clínicas. Trabalho experimental.OBJECTIVE: To carry out a biomechanical study of four techniques for fixation of four-part humeral head fractures. METHODS: The fracture was reproduced in 40 plastic humeri, divided into groups of ten according to the fixation technique, each one employing different fixation resources, in different configurations. The humeral models were mounted on an aluminum scapula, with leather straps simulating the rotator cuff tendons, and submitted to bending and torsion tests in a universal testing machine, using relative stiffness as an evaluation parameter. Assemblies with intact humeri were analyzed for comparison. RESULTS: The biomechanical behavior of the fixation techniques varied within a wide range, where the assemblies including the DCP plate and the 4.5mm diameter screws

  17. Application of UV and X-Ray radiation for refreshing of old latent fingerprints in the cyanoacrylate fuming technique - preliminary study

    International Nuclear Information System (INIS)

    Radiceska, Pavlina; Ristova, Mimoza

    2013-01-01

    The work described below focuses on enhancement/refreshment of older latent fingerprints onto a non porous (glass) surface. The aging of the fingerprints is a major problem of the forensic science, because of the compound’s degradation under the influence of a variety of atmospheric parameters, in addition to the time factor. The humidification extent on the latent fingerprints appeared to be one of the critical factors for the deposition of the cyanoacrylate on the finger-marks, since the unsaturated bonds from lipid content from the latent fingerprints serve as active water condensation centers. In the present work we show results from the enhancement of aged latent fingerprint details by activation of the humidity condensation centers with exposition to UV or X-ray radiation prior to their developing into the cyanoacrylate fuming chamber. The aging of the latent fingerprints on glass surfaces with the time for given conditions was established. A term “critical day” was introduced as the day when the detectable details from the latent fingerprints dropped to one half of the initial number of details, recovered from identical fresh latent fingerprint. As the fingerprints were aged to the “critical day”, one third of the samples were exposed to a UV for 15 minutes, another third to 15 minutes of X-ray radiation and the last third was kept unexposed. All the samples were developed into a single cyanoacrylate fuming process. The results showed that in both UV and X-ray cases, a considerable enhancement/refreshment, in approximately 50% of the aged latent fingerprints, has been achieved with only a short term irradiation (15 minutes). (Author)

  18. Providing detailed information about latent tuberculosis and compliance with the PPD test among healthcare workers in Israel: A randomized controlled study

    Directory of Open Access Journals (Sweden)

    Danielle Taubman

    2013-12-01

    Conclusions: Compliance for latent TB screening is low among HCWs in northeastern Israel. Providing detailed information about latent TB was not associated with increased test compliance. Understanding existing disparities in screening rates and potential barriers to latent TB screening among HCWs is important in order to move forward and successfully increase screening rates.

  19. Refreshing the Aged Latent Fingerprints with Ionizing Radiation Prior to the Cyanoacrylate Fuming Procedure: A Preliminary Study.

    Science.gov (United States)

    Ristova, Mimoza M; Radiceska, Pavlina; Bozinov, Igorco; Barandovski, Lambe

    2016-05-01

    One of the crucial factors determining the cyanoacrylate deposit quality over latent fingerprints appeared to be the extent of the humidity. This work focuses on the enhancement/refreshment of age-degraded latent fingerprints by irradiating the samples with UV, X-ray, or thermal neutrons prior to the cyanoacrylate (CA) fuming. Age degradation of latent fingerprints deposited on glass surfaces was examined through the decrease in the number of characteristic minutiae counts over time. A term "critical day" was introduced for the time at which the average number of identifiable minutiae definitions drops to one-half. Fingerprints older than their "critical day" were exposed to either UV, X-ray, or thermal neutrons. Identical reference samples were kept unexposed. All samples, both reference and irradiated, were developed during a single CA fuming procedure. Comparative latent fingerprint analysis showed that exposure to ionizing radiation enhances the CA fuming, yielding a 20-30% increase in average minutiae count. © 2015 American Academy of Forensic Sciences.

  20. The Latent Reservoir for HIV-1: How Immunologic Memory and Clonal Expansion Contribute to HIV-1 Persistence

    Science.gov (United States)

    Murray, Alexandra J.; Kwon, Kyungyoon J.; Farber, Donna L.; Siliciano, Robert F.

    2016-01-01

    Combination antiretroviral therapy (ART) for HIV-1 infection reduces plasma virus levels to below the limit of detection of clinical assays. However, even with prolonged suppression of viral replication with ART, viremia rebounds rapidly after treatment interruption. Thus ART is not curative. The principal barrier to cure is a remarkably stable reservoir of latent HIV-1 in resting memory CD4+ T cells. Here we consider explanations for the remarkable stability of the latent reservoir. Stability does not appear to reflect replenishment from new infection events but rather normal physiologic processes that provide for immunologic memory. Of particular importance are proliferative processes that drive clonal expansion of infected cells. Recent evidence suggests that in some infected cells, proliferation is a consequence of proviral integration into host genes associated with cell growth. Efforts to cure HIV-1 infection by targeting the latent reservoir may need to consider the potential of latently infected cells to proliferate. PMID:27382129

  1. Stimulation of HIV-1-specific cytolytic T-lymphocytes facilitates elimination of latent viral reservoir after virus reactivation

    Science.gov (United States)

    Shan, Liang; Deng, Kai; Shroff, Neeta S.; Durand, Christine; Rabi, S. Alireza.; Yang, Hung-Chih; Zhang, Hao; Margolick, Joseph B.; Blankson, Joel N.; Siliciano, Robert F.

    2012-01-01

    Summary Highly active antiretroviral therapy (HAART) suppresses HIV-1 replication but cannot eliminate the virus because HIV-1 establishes latent infection. Interruption of HAART leads to a rapid rebound of viremia. Life-long treatment is therefore required. Efforts to purge the latent reservoir have focused on reactivating latent proviruses without inducing global T-cell activation. However, the killing of the infected cells after virus reactivation, which is essential for elimination of the reservoir, has not been assessed. Here we show that after reversal of latency in an in vitro model, infected resting CD4+ T cells survived despite viral cytopathic effects, even in the presence of autologous cytolytic T-lymphocytes (CTL) from most patients on HAART. Antigen-specific stimulation of patient CTLs led to efficient killing of infected cells. These results demonstrate that stimulating HIV-1-specific CTLs prior to reactivating latent HIV-1 may be essential for successful eradication efforts and should be considered in future clinical trials. PMID:22406268

  2. Modeling change in learning strategies throughout higher education: a multi-indicator latent growth perspective.

    Science.gov (United States)

    Coertjens, Liesje; Donche, Vincent; De Maeyer, Sven; Vanthournout, Gert; Van Petegem, Peter

    2013-01-01

    The change in learning strategies during higher education is an important topic of research in the Student Approaches to Learning field. Although the studies on this topic are increasingly longitudinal, analyses have continued to rely primarily on traditional statistical methods. The present research is innovative in the way it uses a multi-indicator latent growth analysis in order to more accurately estimate the general and differential development in learning strategy scales. Moreover, the predictive strength of the latent growth models are estimated. The sample consists of one cohort of Flemish University College students, 245 of whom participated in the three measurement waves by filling out the processing and regulation strategies scales of the Inventory of Learning Styles--Short Versions. Independent-samples t-tests revealed that the longitudinal group is a non-random subset of students starting University College. For each scale, a multi-indicator latent growth model is estimated using Mplus 6.1. Results suggest that, on average, during higher education, students persisting in their studies in a non-delayed manner seem to shift towards high-quality learning and away from undirected and surface-oriented learning. Moreover, students from the longitudinal group are found to vary in their initial levels, while, unexpectedly, not in their change over time. Although the growth models fit the data well, significant residual variances in the latent factors remain.

  3. Coordination of KSHV Latent and Lytic Gene Control by CTCF-Cohesin Mediated Chromosome Conformation

    Science.gov (United States)

    Kang, Hyojeung; Wiedmer, Andreas; Yuan, Yan; Robertson, Erle; Lieberman, Paul M.

    2011-01-01

    Herpesvirus persistence requires a dynamic balance between latent and lytic cycle gene expression, but how this balance is maintained remains enigmatic. We have previously shown that the Kaposi's Sarcoma-Associated Herpesvirus (KSHV) major latency transcripts encoding LANA, vCyclin, vFLIP, v-miRNAs, and Kaposin are regulated, in part, by a chromatin organizing element that binds CTCF and cohesins. Using viral genome-wide chromatin conformation capture (3C) methods, we now show that KSHV latency control region is physically linked to the promoter regulatory region for ORF50, which encodes the KSHV immediate early protein RTA. Other linkages were also observed, including an interaction between the 5′ and 3′ end of the latency transcription cluster. Mutation of the CTCF-cohesin binding site reduced or eliminated the chromatin conformation linkages, and deregulated viral transcription and genome copy number control. siRNA depletion of CTCF or cohesin subunits also disrupted chromosomal linkages and deregulated viral latent and lytic gene transcription. Furthermore, the linkage between the latent and lytic control region was subject to cell cycle fluctuation and disrupted during lytic cycle reactivation, suggesting that these interactions are dynamic and regulatory. Our findings indicate that KSHV genomes are organized into chromatin loops mediated by CTCF and cohesin interactions, and that these inter-chromosomal linkages coordinate latent and lytic gene control. PMID:21876668

  4. Use of a Latent Topic Model for Characteristic Extraction from Health Checkup Questionnaire Data.

    Science.gov (United States)

    Hatakeyama, Y; Miyano, I; Kataoka, H; Nakajima, N; Watabe, T; Yasuda, N; Okuhara, Y

    2015-01-01

    When patients complete questionnaires during health checkups, many of their responses are subjective, making topic extraction difficult. Therefore, the purpose of this study was to develop a model capable of extracting appropriate topics from subjective data in questionnaires conducted during health checkups. We employed a latent topic model to group the lifestyle habits of the study participants and represented their responses to items on health checkup questionnaires as a probability model. For the probability model, we used latent Dirichlet allocation to extract 30 topics from the questionnaires. According to the model parameters, a total of 4381 study participants were then divided into groups based on these topics. Results from laboratory tests, including blood glucose level, triglycerides, and estimated glomerular filtration rate, were compared between each group, and these results were then compared with those obtained by hierarchical clustering. If a significant (p topic model and hierarchical clustering grouping revealed that, in the latent topic model method, a small group of participants who reported having subjective signs of urinary disorder were allocated to a single group. The latent topic model is useful for extracting characteristics from a small number of groups from questionnaires with a large number of items. These results show that, in addition to chief complaints and history of past illness, questionnaire data obtained during medical checkups can serve as useful judgment criteria for assessing the conditions of patients.

  5. Modeling change in learning strategies throughout higher education: a multi-indicator latent growth perspective.

    Directory of Open Access Journals (Sweden)

    Liesje Coertjens

    Full Text Available The change in learning strategies during higher education is an important topic of research in the Student Approaches to Learning field. Although the studies on this topic are increasingly longitudinal, analyses have continued to rely primarily on traditional statistical methods. The present research is innovative in the way it uses a multi-indicator latent growth analysis in order to more accurately estimate the general and differential development in learning strategy scales. Moreover, the predictive strength of the latent growth models are estimated. The sample consists of one cohort of Flemish University College students, 245 of whom participated in the three measurement waves by filling out the processing and regulation strategies scales of the Inventory of Learning Styles--Short Versions. Independent-samples t-tests revealed that the longitudinal group is a non-random subset of students starting University College. For each scale, a multi-indicator latent growth model is estimated using Mplus 6.1. Results suggest that, on average, during higher education, students persisting in their studies in a non-delayed manner seem to shift towards high-quality learning and away from undirected and surface-oriented learning. Moreover, students from the longitudinal group are found to vary in their initial levels, while, unexpectedly, not in their change over time. Although the growth models fit the data well, significant residual variances in the latent factors remain.

  6. Prevalence of latent tuberculosis and treatment adherence among patients with chronic kidney disease in Campo Grande, State of Mato Grosso do Sul

    Directory of Open Access Journals (Sweden)

    Aucely Corrêa Fernandes Chagas

    2014-04-01

    Full Text Available Introduction The primary strategy for tuberculosis control involves identifying individuals with latent tuberculosis. This study aimed to estimate the prevalence of latent tuberculosis in chronic kidney disease (CKD patients who were undergoing hemodialysis in Campo Grande, State of Mato Grosso do Sul, Brazil, to characterize the sociodemographic and clinical profiles of patients with latent tuberculosis, to verify the association between sociodemographic and clinical characteristics and the occurrence of latent tuberculosis, and to monitor patient adherence to latent tuberculosis treatment. Methods This epidemiological study involved 418 CKD patients who were undergoing hemodialysis and who underwent a tuberculin skin test. Results The prevalence of latent tuberculosis was 10.3%. The mean patient age was 53.43±14.97 years, and the patients were predominantly men (63.9%. The population was primarily Caucasian (58.6%; half (50% were married, and 49.8% had incomplete primary educations. Previous contact with tuberculosis patients was reported by 80% of the participants. Treatment adherence was 97.7%. Conclusions We conclude that the prevalence of latent tuberculosis in our study population was low. Previous contact with patients with active tuberculosis increased the occurrence of latent infection. Although treatment adherence was high in this study, it is crucial to monitor tuberculosis treatment administered to patients in health services to maintain this high rate.

  7. Latent interaction effects in the theory of planned behaviour applied to quitting smoking.

    Science.gov (United States)

    Hukkelberg, Silje Sommer; Hagtvet, Knut A; Kovac, Velibor Bobo

    2014-02-01

    This study applies three latent interaction models in the theory of planned behaviour (TPB; Ajzen, 1988, Attitudes, personality, and behavior. Homewood, IL: Dorsey Press; Ajzen, 1991, Organ. Behav. Hum. Decis. Process., 50, 179) to quitting smoking: (1) attitude × perceived behavioural control on intention; (2) subjective norms (SN) × attitude on intention; and (3) perceived behavioural control × intention on quitting behaviour. The data derive from a longitudinal Internet survey of 939 smokers aged 15-74 over a period of 4 months. Latent interaction effects were estimated using the double-mean-centred unconstrained approach (Lin et al., 2010, Struct. Equ. Modeling, 17, 374) in LISREL. Attitude × SN and attitude × perceived behavioural control both showed a significant interaction effect on intention. No significant interaction effect was found for perceived behavioural control × intention on quitting. The latent interaction approach is a useful method for investigating specific conditions between TPB components in the context of quitting behaviour. Theoretical and practical implications of the results are discussed. © 2013 The British Psychological Society.

  8. Cross-covariance functions for multivariate random fields based on latent dimensions

    KAUST Repository

    Apanasovich, T. V.; Genton, M. G.

    2010-01-01

    The problem of constructing valid parametric cross-covariance functions is challenging. We propose a simple methodology, based on latent dimensions and existing covariance models for univariate random fields, to develop flexible, interpretable

  9. Mental toughness latent profiles in endurance athletes.

    Science.gov (United States)

    Zeiger, Joanna S; Zeiger, Robert S

    2018-01-01

    Mental toughness in endurance athletes, while an important factor for success, has been scarcely studied. An online survey was used to examine eight mental toughness factors in endurance athletes. The study aim was to determine mental toughness profiles via latent profile analysis in endurance athletes and whether associations exist between the latent profiles and demographics and sports characteristics. Endurance athletes >18 years of age were recruited via social media outlets (n = 1245, 53% female). Mental toughness was measured using the Sports Mental Toughness Questionnaire (SMTQ), Psychological Performance Inventory-Alternative (PPI-A), and self-esteem was measured using the Rosenberg Self-Esteem Scale (RSE). A three-class solution emerged, designated as high mental toughness (High MT), moderate mental toughness (Moderate MT) and low mental toughness (Low MT). ANOVA tests showed significant differences between all three classes on all 8 factors derived from the SMTQ, PPI-A and the RSE. There was an increased odds of being in the High MT class compared to the Low MT class for males (OR = 1.99; 95% CI, 1.39, 2.83; Pathletes who were over 55 compared to those who were 18-34 (OR = 2.52; 95% CI, 1.37, 4.62; Pathletes. High MT is associated with demographics and sports characteristics. Mental toughness screening in athletes may help direct practitioners with mental skills training.

  10. Single-Cell RNA-Seq Reveals Transcriptional Heterogeneity in Latent and Reactivated HIV-Infected Cells.

    Science.gov (United States)

    Golumbeanu, Monica; Cristinelli, Sara; Rato, Sylvie; Munoz, Miguel; Cavassini, Matthias; Beerenwinkel, Niko; Ciuffi, Angela

    2018-04-24

    Despite effective treatment, HIV can persist in latent reservoirs, which represent a major obstacle toward HIV eradication. Targeting and reactivating latent cells is challenging due to the heterogeneous nature of HIV-infected cells. Here, we used a primary model of HIV latency and single-cell RNA sequencing to characterize transcriptional heterogeneity during HIV latency and reactivation. Our analysis identified transcriptional programs leading to successful reactivation of HIV expression. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

  11. Latent segmentation based count models: Analysis of bicycle safety in Montreal and Toronto.

    Science.gov (United States)

    Yasmin, Shamsunnahar; Eluru, Naveen

    2016-10-01

    The study contributes to literature on bicycle safety by building on the traditional count regression models to investigate factors affecting bicycle crashes at the Traffic Analysis Zone (TAZ) level. TAZ is a traffic related geographic entity which is most frequently used as spatial unit for macroscopic crash risk analysis. In conventional count models, the impact of exogenous factors is restricted to be the same across the entire region. However, it is possible that the influence of exogenous factors might vary across different TAZs. To accommodate for the potential variation in the impact of exogenous factors we formulate latent segmentation based count models. Specifically, we formulate and estimate latent segmentation based Poisson (LP) and latent segmentation based Negative Binomial (LNB) models to study bicycle crash counts. In our latent segmentation approach, we allow for more than two segments and also consider a large set of variables in segmentation and segment specific models. The formulated models are estimated using bicycle-motor vehicle crash data from the Island of Montreal and City of Toronto for the years 2006 through 2010. The TAZ level variables considered in our analysis include accessibility measures, exposure measures, sociodemographic characteristics, socioeconomic characteristics, road network characteristics and built environment. A policy analysis is also conducted to illustrate the applicability of the proposed model for planning purposes. This macro-level research would assist decision makers, transportation officials and community planners to make informed decisions to proactively improve bicycle safety - a prerequisite to promoting a culture of active transportation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Incorporating Latent Variables into Discrete Choice Models - A Simultaneous Estimation Approach Using SEM Software

    Directory of Open Access Journals (Sweden)

    Dirk Temme

    2008-12-01

    Full Text Available Integrated choice and latent variable (ICLV models represent a promising new class of models which merge classic choice models with the structural equation approach (SEM for latent variables. Despite their conceptual appeal, applications of ICLV models in marketing remain rare. We extend previous ICLV applications by first estimating a multinomial choice model and, second, by estimating hierarchical relations between latent variables. An empirical study on travel mode choice clearly demonstrates the value of ICLV models to enhance the understanding of choice processes. In addition to the usually studied directly observable variables such as travel time, we show how abstract motivations such as power and hedonism as well as attitudes such as a desire for flexibility impact on travel mode choice. Furthermore, we show that it is possible to estimate such a complex ICLV model with the widely available structural equation modeling package Mplus. This finding is likely to encourage more widespread application of this appealing model class in the marketing field.

  13. Latent uncertainties of the precalculated track Monte Carlo method

    Energy Technology Data Exchange (ETDEWEB)

    Renaud, Marc-André; Seuntjens, Jan [Medical Physics Unit, McGill University, Montreal, Quebec H3G 1A4 (Canada); Roberge, David [Département de radio-oncologie, Centre Hospitalier de l’Université de Montréal, Montreal, Quebec H2L 4M1 (Canada)

    2015-01-15

    Purpose: While significant progress has been made in speeding up Monte Carlo (MC) dose calculation methods, they remain too time-consuming for the purpose of inverse planning. To achieve clinically usable calculation speeds, a precalculated Monte Carlo (PMC) algorithm for proton and electron transport was developed to run on graphics processing units (GPUs). The algorithm utilizes pregenerated particle track data from conventional MC codes for different materials such as water, bone, and lung to produce dose distributions in voxelized phantoms. While PMC methods have been described in the past, an explicit quantification of the latent uncertainty arising from the limited number of unique tracks in the pregenerated track bank is missing from the paper. With a proper uncertainty analysis, an optimal number of tracks in the pregenerated track bank can be selected for a desired dose calculation uncertainty. Methods: Particle tracks were pregenerated for electrons and protons using EGSnrc and GEANT4 and saved in a database. The PMC algorithm for track selection, rotation, and transport was implemented on the Compute Unified Device Architecture (CUDA) 4.0 programming framework. PMC dose distributions were calculated in a variety of media and compared to benchmark dose distributions simulated from the corresponding general-purpose MC codes in the same conditions. A latent uncertainty metric was defined and analysis was performed by varying the pregenerated track bank size and the number of simulated primary particle histories and comparing dose values to a “ground truth” benchmark dose distribution calculated to 0.04% average uncertainty in voxels with dose greater than 20% of D{sub max}. Efficiency metrics were calculated against benchmark MC codes on a single CPU core with no variance reduction. Results: Dose distributions generated using PMC and benchmark MC codes were compared and found to be within 2% of each other in voxels with dose values greater than 20% of

  14. Latent uncertainties of the precalculated track Monte Carlo method

    International Nuclear Information System (INIS)

    Renaud, Marc-André; Seuntjens, Jan; Roberge, David

    2015-01-01

    Purpose: While significant progress has been made in speeding up Monte Carlo (MC) dose calculation methods, they remain too time-consuming for the purpose of inverse planning. To achieve clinically usable calculation speeds, a precalculated Monte Carlo (PMC) algorithm for proton and electron transport was developed to run on graphics processing units (GPUs). The algorithm utilizes pregenerated particle track data from conventional MC codes for different materials such as water, bone, and lung to produce dose distributions in voxelized phantoms. While PMC methods have been described in the past, an explicit quantification of the latent uncertainty arising from the limited number of unique tracks in the pregenerated track bank is missing from the paper. With a proper uncertainty analysis, an optimal number of tracks in the pregenerated track bank can be selected for a desired dose calculation uncertainty. Methods: Particle tracks were pregenerated for electrons and protons using EGSnrc and GEANT4 and saved in a database. The PMC algorithm for track selection, rotation, and transport was implemented on the Compute Unified Device Architecture (CUDA) 4.0 programming framework. PMC dose distributions were calculated in a variety of media and compared to benchmark dose distributions simulated from the corresponding general-purpose MC codes in the same conditions. A latent uncertainty metric was defined and analysis was performed by varying the pregenerated track bank size and the number of simulated primary particle histories and comparing dose values to a “ground truth” benchmark dose distribution calculated to 0.04% average uncertainty in voxels with dose greater than 20% of D max . Efficiency metrics were calculated against benchmark MC codes on a single CPU core with no variance reduction. Results: Dose distributions generated using PMC and benchmark MC codes were compared and found to be within 2% of each other in voxels with dose values greater than 20% of the

  15. Linear latent variable models: the lava-package

    DEFF Research Database (Denmark)

    Holst, Klaus Kähler; Budtz-Jørgensen, Esben

    2013-01-01

    are implemented including robust standard errors for clustered correlated data, multigroup analyses, non-linear parameter constraints, inference with incomplete data, maximum likelihood estimation with censored and binary observations, and instrumental variable estimators. In addition an extensive simulation......An R package for specifying and estimating linear latent variable models is presented. The philosophy of the implementation is to separate the model specification from the actual data, which leads to a dynamic and easy way of modeling complex hierarchical structures. Several advanced features...

  16. Exploring galaxy evolution with latent space walks

    Science.gov (United States)

    Schawinski, Kevin; Turp, Dennis; Zhang, Ce

    2018-01-01

    We present a new approach using artificial intelligence to perform data-driven forward models of astrophysical phenomena. We describe how a variational autoencoder can be used to encode galaxies to latent space, independently manipulate properties such as the specific star formation rate, and return it to real space. Such transformations can be used for forward modeling phenomena using data as the only constraints. We demonstrate the utility of this approach using the question of the quenching of star formation in galaxies.

  17. Some children with autism have latent social skills that can be tested

    Directory of Open Access Journals (Sweden)

    Hrdlicka M

    2017-03-01

    Full Text Available Michal Hrdlicka,1 Tomas Urbanek,2 Maria Vacova,1 Stepanka Beranova,1 Iva Dudova1 1Department of Child Psychiatry, Charles University Second Faculty of Medicine and University Hospital Motol, Prague, 2Institute of Psychology, Academy of Sciences, Brno, Czech Republic Background: The idea of latent social skills in autism emerged as a possible interpretation of the rapid (but temporary improvement of autistic subjects in oxytocin studies. We tested a hypothesis that a normal response to Item No 59 “Secure Base” from the third version of the Autism Diagnostic Interview – Revised (ADIR-59 could indicate the presence of latent social skills in autism.Methods: We examined 110 autistic children (88 boys and 22 girls with a mean age of 6.0±2.5 years (range: 2.2–14.8 years using the Autism Diagnostic Observation Schedule (ADOS – Generic. A diagnosis of mental retardation was established in 68 autistic children (62%.Results: The difference in the ADOS social domain between children aged ≤5 years on one side and children older than 5 years on the other side was significant in subjects with normal responses to ADIR-59 (9.60 vs 6.47; P=0.031 but not in those with abnormal responses to ADIR-59 (10.62 vs 9.63; P=0.537. In a predictive model, lower ADOS social domain scores were predicted by older age (P=0.001, lower scores on the ADIR-59 (P=0.01, and the absence of mental retardation (P=0.049.Conclusion: The results support the hypothesis that the normal response to item ADIR-59 “Secure Base” indicates the presence of latent social skills in autism that might foretell further social growth in older autistic subjects. Keywords: autism, latent social skills, Autism Diagnostic Interview – Revised, Autism Diagnostic Observation Schedule, prediction

  18. Thermal Studies of Zn(II, Cd(II and Hg(II Complexes of Some <em>N-Alkyl-N>-Phenyl-Dithiocarbamates

    Directory of Open Access Journals (Sweden)

    Peter A. Ajibade

    2012-07-01

    Full Text Available The thermal decomposition of Zn(II, Cd(II and Hg(II complexes of <em>N-ethyl-N>-phenyl and <em>N-butyl-N>-phenyl dithiocarbamates have been studied using thermogravimetric analysis (TGA and differential scanning calorimetry (DSC. The products of the decomposition, at two different temperatures, were further characterized by scanning electron microscopy (SEM and energy-dispersive X-ray spectroscopy (EDX. The results show that while the zinc and cadmium complexes undergo decomposition to form metal sulphides, and further undergo oxidation forming metal oxides as final products, the mercury complexes gave unstable volatiles as the final product.

  19. Agroecology and the Sustainable Production of Food and ...

    Science.gov (United States)

    The silvopastoral, agricultural system of the montado in Southern Portugal is an example of the self-organization of an agroecological system adapted to the climate and soil conditions of the Mediterranean basin. This system with its consistent production of food, fiber, and ecosystem services along with its concomitant rural social organization has been sustained in the region for over 1000 years. However, the system has been gradually decreasing in extent since the 19th century and its rate of decline has accelerated since the 1980s. The causes of this decline have been traced in descending order of importance to land managment choices, spatial factors and environmental factors. In addition, past studies have shown that there is an optimum livestock support capacity for maintaining the health of the montado agroecosystem. In this study, we used the results of an emergy evaluation of a cattle farm as part of a montado agroecosystem to examine the effects of the European Union’s (EU) Common Agricultural Policy (CAP) on the viability of both cattle rearing and the long term regional sustainability of montado agroecosystems. We found that the CAP and its two pillars for providing subsidies, (1) Common Market Organization (CMO) and (2) Rural Development Policy (RDP) are complex and take into account many aspects of prices and markets for particular products, e.g., beef and veal (CMO) and sustainable rural development, e.g., silvopastoral agroecosystems (RDP). How

  20. Brain Macrophages in Simian Immunodeficiency Virus-Infected, Antiretroviral-Suppressed Macaques: a Functional Latent Reservoir.

    Science.gov (United States)

    Avalos, Claudia R; Abreu, Celina M; Queen, Suzanne E; Li, Ming; Price, Sarah; Shirk, Erin N; Engle, Elizabeth L; Forsyth, Ellen; Bullock, Brandon T; Mac Gabhann, Feilim; Wietgrefe, Stephen W; Haase, Ashley T; Zink, M Christine; Mankowski, Joseph L; Clements, Janice E; Gama, Lucio

    2017-08-15

    A human immunodeficiency virus (HIV) infection cure requires an understanding of the cellular and anatomical sites harboring virus that contribute to viral rebound upon treatment interruption. Despite antiretroviral therapy (ART), HIV-associated neurocognitive disorders (HAND) are reported in HIV-infected individuals on ART. Biomarkers for macrophage activation and neuronal damage in cerebrospinal fluid (CSF) of HIV-infected individuals demonstrate continued effects of HIV in brain and suggest that the central nervous system (CNS) may serve as a viral reservoir. Using a simian immunodeficiency virus (SIV)/macaque model for HIV encephalitis and AIDS, we evaluated whether infected cells persist in brain despite ART. Eight SIV-infected pig-tailed macaques were virally suppressed with ART, and plasma and CSF viremia levels were analyzed longitudinally. To assess whether virus persisted in brain macrophages (BrMΦ) in these macaques, we used a macrophage quantitative viral outgrowth assay (MΦ-QVOA), PCR, and in situ hybridization (ISH) to measure the frequency of infected cells and the levels of viral RNA and DNA in brain. Viral RNA in brain tissue of suppressed macaques was undetectable, although viral DNA was detected in all animals. The MΦ-QVOA demonstrated that the majority of suppressed animals contained latently infected BrMΦ. We also showed that virus produced in the MΦ-QVOAs was replication competent, suggesting that latently infected BrMΦ are capable of reestablishing productive infection upon treatment interruption. This report provides the first confirmation of the presence of replication-competent SIV in BrMΦ of ART-suppressed macaques and suggests that the highly debated issue of viral latency in macrophages, at least in brain, has been addressed in SIV-infected macaques treated with ART. IMPORTANCE Resting CD4 + T cells are currently the only cells that fit the definition of a latent reservoir. However, recent evidence suggests that HIV

  1. Providing detailed information about latent tuberculosis and compliance with the PPD test among healthcare workers in Israel: a randomized controlled study.

    Science.gov (United States)

    Taubman, Danielle; Titler, Nava; Edelstein, Hana; Elias, Mazen; Saliba, Walid

    2013-12-01

    The compliance of screening for latent tuberculosis (TB) with the tuberculin purified protein derivative (PPD) test is very low among healthcare workers (HCWs) in Israel. This randomized controlled study uses the Health Belief Model (HBM) as a conceptual framework to examine whether providing more information about latent TB and the PPD test increases the response rate for PPD screening among HCWs. All candidate HCWs for latent TB screening were randomly allocated to one of the following two invitations to perform the PPD test: regular letter (control group, n=97), and a letter with information about latent TB and the PPD test (intervention group, n=196). 293 HCWs were included (185 nurses, and 108 physicians). Overall, 36 (12.3%) HCWs were compliant with the PPD test screening. Compliance with PPD testing in the intervention group was not statistically different from the control group, RR 0.87 (95% CI, 0.46-1.65). Compliance for latent TB screening is low among HCWs in northeastern Israel. Providing detailed information about latent TB was not associated with increased test compliance. Understanding existing disparities in screening rates and potential barriers to latent TB screening among HCWs is important in order to move forward and successfully increase screening rates. Copyright © 2013 Ministry of Health, Saudi Arabia. Published by Elsevier Ltd. All rights reserved.

  2. Preferences, benefits, and park visits: a latent class segmentation analysis

    NARCIS (Netherlands)

    Kemperman, A.D.A.M.; Timmermans, H.J.P.

    2006-01-01

    This study describes and predicts segments of urban park visitors to support park planning and policy making. A latent class analysis is used to identify segments of park users who differ regarding their preferences for park characteristics, benefits sought in park visits, and sociodemographics.

  3. Effect of [gamma]-irradiation on latent tracks of polyethylene terephthalate (PET) film

    Science.gov (United States)

    Hiroki, A.; Asano, M.; Yamaki, T.; Yoshida, M.

    2005-04-01

    The pre-treatment effect of γ-irradiation on latent tracks of polyethylene terephthalate (PET) films bombarded with swift heavy ions was investigated by electric conductometry and scanning electron microscope (SEM) observation. The Xe-ion bombarded PET films were etched for 6 h in 0.2 M NaOH aqueous solution at 70 °C to prepare track-etched membranes. As γ-irradiation doses increased in the range of 0-160 kGy, the surface pore diameter obtained by SEM observation decreased while that obtained by conductometry became large. This inconsistent result between the two methods was due to an increase in the crosslinked region in the latent tracks caused by γ-irradiation.

  4. Bifactor latent structure of attention-deficit/hyperactivity disorder (ADHD)/oppositional defiant disorder (ODD) symptoms and first-order latent structure of sluggish cognitive tempo symptoms.

    Science.gov (United States)

    Lee, SoYean; Burns, G Leonard; Beauchaine, Theodore P; Becker, Stephen P

    2016-08-01

    The objective was to determine if the latent structure of attention-deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD) symptoms is best explained by a general disruptive behavior factor along with specific inattention (IN), hyperactivity/impulsivity (HI), and ODD factors (a bifactor model) whereas the latent structure of sluggish cognitive tempo (SCT) symptoms is best explained by a first-order factor independent of the bifactor model of ADHD/ODD. Parents' (n = 703) and teachers' (n = 366) ratings of SCT, ADHD-IN, ADHD-HI, and ODD symptoms on the Child and Adolescent Disruptive Behavior Inventory (CADBI) in a community sample of children (ages 5-13; 55% girls) were used to evaluate 4 models of symptom organization. Results indicated that a bifactor model of ADHD/ODD symptoms, in conjunction with a separate first-order SCT factor, was the best model for both parent and teacher ratings. The first-order SCT factor showed discriminant validity with the general disruptive behavior and specific IN factors in the bifactor model. In addition, higher scores on the SCT factor predicted greater academic and social impairment, even after controlling for the general disruptive behavior and 3 specific factors. Consistent with predictions from the trait-impulsivity etiological model of externalizing liability, a single, general disruptive behavior factor accounted for nearly all common variance in ADHD/ODD symptoms, whereas SCT symptoms represented a factor different from the general disruptive behavior and specific IN factor. These results provide additional support for distinguishing between SCT and ADHD-IN. The study also demonstrates how etiological models can be used to predict specific latent structures of symptom organization. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  5. Conservazione e gestione della Lepre italica (<em>Lepus corsicanusem>

    Directory of Open Access Journals (Sweden)

    Francesco Riga

    2003-10-01

    Full Text Available Il recente riconoscimento dello <em>status> specifico della Lepre italica (<em>Lepus corsicanusem> e l?accertamento dell?areale distributivo rappresentano le azioni più importanti per la conservazione di un <em>taxon endemicoem> che si era creduto estinto. Nella penisola la specie presenta un areale discontinuo, il cui limite settentrionale è dato dal comune di Manciano (GR, sul versante tirrenico e da una linea che dalla provincia de L'Aquila arriva al Gargano. In Sicilia la distribuzione è relativamente continua anche in aree non protette. Dati genetici hanno permesso di confermare la presenza in Corsica. Al contrario, nell?Isola d'Elba, a seguito di estese ricerche, sono stati identificati solo esemplari di <em>L. europaeusem>. Nell?Italia peninsulare <em>L. corsicanusem> è spesso presente in simpatria con popolazioni di <em>L. europaeusem>, mentre in Sicilia la lepre europea non ha originato popolazioni stabili, nonostante l?immissione di molte migliaia di individui. La distribuzione ecologica di <em>L. corsicanusem> ed analisi ambientali specifiche, suggeriscono l?adattamento prevalente agli ambienti a clima mediterraneo, benché essa sia presente anche a quote elevate (> 1.500 m s.l.m.. Dati preliminari di abbondanza relativa hanno evidenziato una situazione diversificata tra la penisola e la Sicilia e tra aree a diverso regime di gestione; un confronto tra le aree protette ha evidenziato rispettivamente valori di 5,54 e 11,73 ind./km². La riduzione quali-quantitativa e la frammentazione dell?<em>habitat> delle lepri è un fenomeno potenzialmente pericoloso per la sopravvivenza delle popolazioni, determinando fenomeni di estinzione locale dovuti alle basse densità di popolazione, inducendo fenomeni di erosione della variabilità genetica e di riduzione della <em>fitness> degli individui. L?introduzione di <em>L. europaeusem> può costituire un importante fattore limitante sia per la possibile competizione

  6. Controle de Neobenedenia melleni (MacCallum, 1927 (Monogenea: Capsalidae em garoupa-verdadeira, Epinephelus marginatus (Lowe, 1834, cultivada em tanques-rede Control of Neobenedenia melleni (MacCallum, 1927 (Monogenea: Capsalidae in dusky grouper, Epinephelus marginatus (Lowe, 1834, reared in floating net cages

    Directory of Open Access Journals (Sweden)

    Eduardo Gomes Sanches

    2008-09-01

    Full Text Available O diagnóstico precoce de patologias no meio aquático constitui-se em uma necessidade vital para o sucesso dos cultivos. Considerados como parasitos oportunistas, surtos de infestação de monogenóides capsalídeos podem ocasionar mortalidades massivas gerando enormes prejuízos nos cultivos. Exemplares de garoupa-verdadeira Epinephelus marginatus (Lowe, 1834, com peso médio de 142,74 ± 38,65 g, apresentaram recusa da alimentação e sintomas como o escurecimento do corpo, natação errática, opacidade dos olhos, exoftalmia e hemorragias em diversas áreas do corpo. Alguns peixes apresentavam lesões no globo ocular e cegueira. Após análises dos peixes foi identificada a ocorrência do parasito Neobenedenia melleni. Este trabalho teve por objetivo testar o efeito de diferentes tratamentos por imersão em diferentes concentrações de formalina e água doce na erradicação de monogenoides capsalideos na garoupa-verdadeira. Foram testados três tratamentos em forma de banhos: T1 (água doce por 10 minutos; T2 (formalina: 1:2.000 por 10 minutos e T3: (formalina: 1:4.000 por 10 minutos. Os tratamentos foram avaliados através de raspado de tecido epitelial, montados entre lâminas e lamínulas e observado ao microscópio de luz. Observou-se que nas condições testadas o T1 e o T2 foram eficientes na eliminação dos monogenóides capsalídeos na garoupa-verdadeira.The precocious diagnosis of pathologies in the aquatic way is constituted in a vital need for the success of the cultivations. Considered as parasites opportunists, infestations of monogeneans capsalides can cause missal mortalities resulting in enormous damages in the cultivations. Juveniles of dusky grouper Epinephelus marginatus (Lowe, 1834, with medium weight of 142.74 ± 38.65 g, presented refusal of the feeding and symptoms as the darkening of the body, erratic swimming, opacity of the eyes and hemorrhages in several areas of the body. Some fishes presented lesions in the

  7. Complete genome sequence of currant latent virus (genus Cheravirus, family Secoviridae)

    Czech Academy of Sciences Publication Activity Database

    Petrzik, Karel; Koloniuk, Igor; Přibylová, Jaroslava; Špak, Josef

    2016-01-01

    Roč. 161, č. 2 (2016), s. 491-493 ISSN 0304-8608 Institutional support: RVO:60077344 Keywords : Stranded-RNA * complete genome sequence * Currant latent virus Subject RIV: EE - Microbiology, Virology Impact factor: 2.058, year: 2016

  8. Methyl 2-Benzamido-2-(1<em>H>-benzimidazol-1-ylmethoxyacetate

    Directory of Open Access Journals (Sweden)

    Alami Anouar

    2012-09-01

    Full Text Available The heterocyclic carboxylic α-aminoester methyl 2-benzamido-2-(1<em>H>-benzimidazol-1-ylmethoxyacetate is obtained by <em>O>-alkylation of methyl α-azido glycinate <em>N>-benzoylated with 1<em>H>-benzimidazol-1-ylmethanol.

  9. "Latent" infection with Toxoplasma gondii: association with trait aggression and impulsivity in healthy adults.

    Science.gov (United States)

    Cook, Thomas B; Brenner, Lisa A; Cloninger, C Robert; Langenberg, Patricia; Igbide, Ajirioghene; Giegling, Ina; Hartmann, Annette M; Konte, Bettina; Friedl, Marion; Brundin, Lena; Groer, Maureen W; Can, Adem; Rujescu, Dan; Postolache, Teodor T

    2015-01-01

    Latent chronic infection with Toxoplasma gondii (T. gondii), a common neurotropic pathogen, has been previously linked with suicidal self-directed violence (SSDV). We sought to determine if latent infection with T. gondii is associated with trait aggression and impulsivity, intermediate phenotypes for suicidal behavior, in psychiatrically healthy adults. Traits of aggression and impulsivity were analyzed in relationship to IgG antibody seropositivity for T. gondii and two other latent neurotropic infections, herpes simplex virus 1 (HSV1) and cytomegalovirus (CMV). One thousand community-residing adults residing in the Munich metropolitan area with no Axis I or II conditions by SCID for DSM-IV (510 men, 490 women, mean age 53.6 ± 15.8, range 20-74). Plasma samples were tested for IgG antibodies to T. gondii, HSV-1 and CMV by ELISA. Self-reported ratings of trait aggression scores (Questionnaire for Measuring Factors of Aggression [FAF]) and trait impulsivity (Sensation-Seeking Scale-V [SSS-V]) were analyzed using linear multivariate methods. T. gondii IgG seropositivity was significantly associated with higher trait reactive aggression scores among women (p impulsive sensation-seeking (SSS-V Disinhibition) among younger men (p impulsivity, personality traits considered as endophenotypes for SSDV, are associated with latent T. gondii infection in a gender and age-specific manner, and could be further investigated as prognostic and treatment targets in T. gondii-positive individuals at risk for SSDV. Published by Elsevier Ltd.

  10. O MODELO SEBAL PARA ESTUDOS DE CLIMA INTRAURBANO: APLICAÇÃO EM RECIFE, PERNAMBUCO, BRASIL - THE SEBAL MODEL FOR CLIMATE INTRA-URBAN STUDIES: APPLICATION IN RECIFE, PERNAMBUCO, BRAZIL

    Directory of Open Access Journals (Sweden)

    Elvis Bergue Mariz Moreira

    2017-04-01

    Full Text Available O conhecimento dos componentes do balanço de energia em áreas urbanas é de grande importância para os estudos do clima urbano, principalmente quando estas são objeto de análise espacial. O objetivo deste estudo é adaptar o modelo SEBAL (comumente utilizado para fins agroclimatológicos em um ambiente intraurbano, possibilitando análises de componentes microclimáticas com metodologia de baixo custo, através de dados de sensores remotos. A fim de alcançar este objetivo, seis imagens do satélite Landsat 5 TM, entre os anos de 1998 a 2011, foram processadas. Densidade dos fluxos de calor sensível e latente foram calculadas usando o algoritmo SEBAL. De acordo com os resultados, o elevado percentual de superfícies impermeáveis e a distribuição espacial reduzida de áreas verdes modificam as trocas entre os fluxos de radiação, proporcionando assim altos níveis de fluxos de energia disponíveis para o aumento da temperatura do ar. A este respeito, o setor oriental se destaca por seus valores de magnitude mais altas, entre 216 e 425 Wm-2. A área Sul produziu alguns valores em excesso de 426 Wm-2. O fluxo de calor latente (LE apresentou diminuição da distribuição espacial; sendo concentrada em áreas protegidas designadas e corpos d'água com valores superiores a 431 Wm-2. Torna-se evidente que os padrões intensivos de uso da terra não coincidem com planejamento adequado e refletem sobre a qualidade de vida da população. ABSTRACT The knowledge of the components of the energy balance in urban areas is of relevant to the studies of the urban climate, mainly when those are subject to spatial analysis. The objective of this study is to adapt the SEBAL - Surface Energy Balance Algorithm for Land model (commonly used to agroclimatic purposes in a intra-urban environment, enabling analysis of microclimate components with low cost methodology through remote sensing data. In order to accomplish this goal, six satellite Landsat 5 TM

  11. Identification of Chinese medicine syndromes in persistent insomnia associated with major depressive disorder: a latent tree analysis.

    Science.gov (United States)

    Yeung, Wing-Fai; Chung, Ka-Fai; Zhang, Nevin Lian-Wen; Zhang, Shi Ping; Yung, Kam-Ping; Chen, Pei-Xian; Ho, Yan-Yee

    2016-01-01

    Chinese medicine (CM) syndrome (zheng) differentiation is based on the co-occurrence of CM manifestation profiles, such as signs and symptoms, and pulse and tongue features. Insomnia is a symptom that frequently occurs in major depressive disorder despite adequate antidepressant treatment. This study aims to identify co-occurrence patterns in participants with persistent insomnia and major depressive disorder from clinical feature data using latent tree analysis, and to compare the latent variables with relevant CM syndromes. One hundred and forty-two participants with persistent insomnia and a history of major depressive disorder completed a standardized checklist (the Chinese Medicine Insomnia Symptom Checklist) specially developed for CM syndrome classification of insomnia. The checklist covers symptoms and signs, including tongue and pulse features. The clinical features assessed by the checklist were analyzed using Lantern software. CM practitioners with relevant experience compared the clinical feature variables under each latent variable with reference to relevant CM syndromes, based on a previous review of CM syndromes. The symptom data were analyzed to build the latent tree model and the model with the highest Bayes information criterion score was regarded as the best model. This model contained 18 latent variables, each of which divided participants into two clusters. Six clusters represented more than 50 % of the sample. The clinical feature co-occurrence patterns of these six clusters were interpreted as the CM syndromes Liver qi stagnation transforming into fire, Liver fire flaming upward, Stomach disharmony, Hyperactivity of fire due to yin deficiency, Heart-kidney noninteraction, and Qi deficiency of the heart and gallbladder. The clinical feature variables that contributed significant cumulative information coverage (at least 95 %) were identified. Latent tree model analysis on a sample of depressed participants with insomnia revealed 13 clinical

  12. Estimation of bulk transfer coefficient for latent heat flux (Ce)

    Digital Repository Service at National Institute of Oceanography (India)

    Sadhuram, Y.

    The bulk transfer coefficient for latent heat flux (Ce) has been estimated over the Arabian Sea from the moisture budget during the pre-monsoon season of 1988. The computations have been made over two regions (A: 0-8 degrees N: 60-68 degrees E: B: 0...

  13. Taxometric evidence of a dimensional latent structure for depression in an epidemiological sample of children and adolescents.

    Science.gov (United States)

    Liu, R T

    2016-04-01

    A basic phenomenological question of much theoretical and empirical interest is whether the latent structure of depression is dimensional or categorical in nature. Prior taxometric studies of youth depression have yielded mixed findings. In a step towards resolving these contradictory findings, the current taxometric investigation is the first to utilize a recently developed objective index, the comparison curve fit index, to evaluate the latent structure of major depression in an epidemiological sample of children and adolescents. Data were derived from Mental Health of Children and Young People in Great Britain surveys. Participants were administered a structured diagnostic interview to assess for current depression. Parents (n = 683) were interviewed for children aged 5-16 years, and child interviews (n = 605) were conducted for those aged 11-16 years. MAMBAC (mean above minus below a cut), MAXEIG (maximum eigenvalue) and L-Mode (latent mode) analyses provided convergent support for a dimensional latent structure. The current findings suggest that depression in youth is more accurately conceptualized as a continuous syndrome rather than a discrete diagnostic entity.

  14. Latent period and temporal aspects of lung cancer among miners

    International Nuclear Information System (INIS)

    Sun Shiquan; Yang Xiaoou; Yang Lan; Meng Xianyu; Liu Shengen; You Zhanyun

    1984-01-01

    Data of lung cancer happened in the miners of this reported mine area is of great value to investigate the temporal aspects of miner's lung cancer, owing to its plenty of cases, longterm follow up and mining as child miners in early years before liberation of China. This preliminary analysis showed that the induction-latent period increased with the decrease of age at the year-of-first-employment in this mine and the protraction of follow up. In other words, even they were exposed since childhood, the excess of lung cancer never appeared until certain age for carcinogenesis. Therefore, the long-term follow up and comprehensive analysis of induction-latent period, underground duration-of-employment, time and age at start of mining would be helpful to properly estimating risk level, discovering the cause and predicting the trend of lung cancer incidence. There is no evidence to show whether child miners are more sensitive than adult miners working at the same exposure conditions

  15. Acetone facilitated DNA sampling from electrical tapes improves DNA recovery and enables latent fingerprints development.

    Science.gov (United States)

    Feine, Ilan; Shpitzen, Moshe; Geller, Boris; Salmon, Eran; Peleg, Tsach; Roth, Jonathan; Gafny, Ron

    2017-07-01

    Electrical tapes (ETs) are a common component of improvised explosive devices (IEDs) used by terrorists or criminal organizations and represent a valuable forensic resource for DNA and latent fingerprints recovery. However, DNA recovery rates are typically low and usually below the minimal amount required for amplification. In addition, most DNA extraction methods are destructive and do not allow further latent fingerprints development. In the present study a cell culture based touch DNA model was used to demonstrate a two-step acetone-water DNA recovery protocol from ETs. This protocol involves only the adhesive side of the ET and increases DNA recovery rates by up to 70%. In addition, we demonstrated partially successful latent fingerprints development from the non-sticky side of the ETs. Taken together, this protocol maximizes the forensic examination of ETs and is recommended for routine casework processing. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Interaction between Helicobacter pylori and latent toxoplasmosis and demographic variables on cognitive function in young to middle-aged adults.

    Science.gov (United States)

    Gale, Shawn D; Erickson, Lance D; Brown, Bruce L; Hedges, Dawson W

    2015-01-01

    Helicobacter pylori and latent toxoplasmosis are widespread diseases that have been associated with cognitive deficits and Alzheimer's disease. We sought to determine whether interactions between Helicobacter pylori and latent toxoplasmosis, age, race-ethnicity, educational attainment, economic status, and general health predict cognitive function in young and middle-aged adults. To do so, we used multivariable regression and multivariate models to analyze data obtained from the United States' National Health and Nutrition Examination Survey from the Centers for Disease Control and Prevention, which can be weighted to represent the US population. In this sample, we found that 31.6 percent of women and 36.2 percent of men of the overall sample had IgG Antibodies against Helicobacter pylori, although the seroprevalence of Helicobacter pylori varied with sociodemographic variables. There were no main effects for Helicobacter pylori or latent toxoplasmosis for any of the cognitive measures in models adjusting for age, sex, race-ethnicity, educational attainment, economic standing, and self-rated health predicting cognitive function. However, interactions between Helicobacter pylori and race-ethnicity, educational attainment, latent toxoplasmosis in the fully adjusted models predicted cognitive function. People seropositive for both Helicobacter pylori and latent toxoplasmosis - both of which appear to be common in the general population - appear to be more susceptible to cognitive deficits than are people seropositive for either Helicobacter pylori and or latent toxoplasmosis alone, suggesting a synergistic effect between these two infectious diseases on cognition in young to middle-aged adults.

  17. Interaction between Helicobacter pylori and latent toxoplasmosis and demographic variables on cognitive function in young to middle-aged adults.

    Directory of Open Access Journals (Sweden)

    Shawn D Gale

    Full Text Available Helicobacter pylori and latent toxoplasmosis are widespread diseases that have been associated with cognitive deficits and Alzheimer's disease. We sought to determine whether interactions between Helicobacter pylori and latent toxoplasmosis, age, race-ethnicity, educational attainment, economic status, and general health predict cognitive function in young and middle-aged adults. To do so, we used multivariable regression and multivariate models to analyze data obtained from the United States' National Health and Nutrition Examination Survey from the Centers for Disease Control and Prevention, which can be weighted to represent the US population. In this sample, we found that 31.6 percent of women and 36.2 percent of men of the overall sample had IgG Antibodies against Helicobacter pylori, although the seroprevalence of Helicobacter pylori varied with sociodemographic variables. There were no main effects for Helicobacter pylori or latent toxoplasmosis for any of the cognitive measures in models adjusting for age, sex, race-ethnicity, educational attainment, economic standing, and self-rated health predicting cognitive function. However, interactions between Helicobacter pylori and race-ethnicity, educational attainment, latent toxoplasmosis in the fully adjusted models predicted cognitive function. People seropositive for both Helicobacter pylori and latent toxoplasmosis - both of which appear to be common in the general population - appear to be more susceptible to cognitive deficits than are people seropositive for either Helicobacter pylori and or latent toxoplasmosis alone, suggesting a synergistic effect between these two infectious diseases on cognition in young to middle-aged adults.

  18. Stability of alcohol use and teen dating violence for female youth: A latent transition analysis.

    Science.gov (United States)

    Choi, Hye Jeong; Elmquist, JoAnna; Shorey, Ryan C; Rothman, Emily F; Stuart, Gregory L; Temple, Jeff R

    2017-01-01

    Alcohol use is one of the most widely accepted and studied risk factors for teen dating violence (TDV). Too little research has explored longitudinally if it is true that an adolescent's alcohol use and TDV involvement simultaneously occur. In the current study, we examined whether there were latent status based on past-year TDV and alcohol use and whether female adolescents changed their statuses of TDV and alcohol use over time. The sample consisted of 583 female youths in seven public high schools in Texas. Three waves of longitudinal data collected from 2011 to 2013 were utilised in this study. Participants completed self-report assessments of alcohol use (past-year alcohol use, number of drinks in the past month and episodic heavy drinking within the past month) and psychological and physical TDV victimisation and perpetration. Latent transition analysis was used to examine if the latent status based on TDV and alcohol use changed over time. Five separate latent statuses were identified: (i) no violence, no alcohol; (ii) alcohol; (iii) psychological violence, no alcohol; (iv) psychological violence, alcohol; and (v) physical and psychological violence, alcohol. Latent transition analysis indicated that adolescents generally remained in the same subgroup across time. This study provides evidence on the co-occurrence of alcohol use and teen dating violence, and whether teens' status based on dating violence and alcohol use are stable over time. Findings from the current study highlight the importance of targeting both TDV and substance use in intervention and prevention programs. [Choi HJ, Elmquist J, Shorey RC, Rothman EF, Stuart GL,Temple JR. Stability of alcohol use and teen dating violence for female youth: Alatent transition analysis. Drug Alcohol Rev 2017;36:80-87]. © 2017 Australasian Professional Society on Alcohol and other Drugs.

  19. Machine-assisted verification of latent fingerprints: first results for nondestructive contact-less optical acquisition techniques with a CWL sensor

    Science.gov (United States)

    Hildebrandt, Mario; Kiltz, Stefan; Krapyvskyy, Dmytro; Dittmann, Jana; Vielhauer, Claus; Leich, Marcus

    2011-11-01

    A machine-assisted analysis of traces from crime scenes might be possible with the advent of new high-resolution non-destructive contact-less acquisition techniques for latent fingerprints. This requires reliable techniques for the automatic extraction of fingerprint features from latent and exemplar fingerprints for matching purposes using pattern recognition approaches. Therefore, we evaluate the NIST Biometric Image Software for the feature extraction and verification of contact-lessly acquired latent fingerprints to determine potential error rates. Our exemplary test setup includes 30 latent fingerprints from 5 people in two test sets that are acquired from different surfaces using a chromatic white light sensor. The first test set includes 20 fingerprints on two different surfaces. It is used to determine the feature extraction performance. The second test set includes one latent fingerprint on 10 different surfaces and an exemplar fingerprint to determine the verification performance. This utilized sensing technique does not require a physical or chemical visibility enhancement of the fingerprint residue, thus the original trace remains unaltered for further investigations. No particular feature extraction and verification techniques have been applied to such data, yet. Hence, we see the need for appropriate algorithms that are suitable to support forensic investigations.

  20. The Oncolytic Virus MG1 Targets and Eliminates Cells Latently Infected With HIV-1: Implications for an HIV Cure.

    Science.gov (United States)

    Ranganath, Nischal; Sandstrom, Teslin S; Burke Schinkel, Stephanie C; Côté, Sandra C; Angel, Jonathan B

    2018-02-14

    Cells latently infected with human immunodeficiency virus (HIV) evade immune- and drug-mediated clearance. These cells harbor intracellular signaling defects, including impairment of the antiviral type I interferon response. Such defects have also been observed in several cancers and have been exploited for the development of therapeutic oncolytic viruses, including the recombinant Maraba virus (MG1). We therefore hypothesized that MG1 would infect and eliminate cells latently infected with HIV-1, while sparing healthy uninfected cells. Preferential infection and elimination by MG1 was first demonstrated in cell lines latently infected with HIV-1. Following this, a reduction in HIV-1 DNA and inducible HIV-1 replication was observed following MG1 infection of latently infected, resting CD4+ T cells generated using an in vitro model of latency. Last, MG1 infection resulted in a reduction in HIV-1 DNA and inducible HIV-1 replication in memory CD4+ T cells isolated from effectively treated, HIV-1-infected individuals. Our results therefore highlight a novel approach to eliminate the latent HIV-1 reservoir. © The Author(s) 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

  1. Evaluating measurement models in clinical research: covariance structure analysis of latent variable models of self-conception.

    Science.gov (United States)

    Hoyle, R H

    1991-02-01

    Indirect measures of psychological constructs are vital to clinical research. On occasion, however, the meaning of indirect measures of psychological constructs is obfuscated by statistical procedures that do not account for the complex relations between items and latent variables and among latent variables. Covariance structure analysis (CSA) is a statistical procedure for testing hypotheses about the relations among items that indirectly measure a psychological construct and relations among psychological constructs. This article introduces clinical researchers to the strengths and limitations of CSA as a statistical procedure for conceiving and testing structural hypotheses that are not tested adequately with other statistical procedures. The article is organized around two empirical examples that illustrate the use of CSA for evaluating measurement models with correlated error terms, higher-order factors, and measured and latent variables.

  2. Indentifying Latent Classes and Testing Their Determinants in Early Adolescents' Use of Computers and Internet for Learning

    Science.gov (United States)

    Heo, Gyun

    2013-01-01

    The purpose of the present study was to identify latent classes resting on early adolescents' change trajectory patterns in using computers and the Internet for learning and to test the effects of gender, self-control, self-esteem, and game use in South Korea. Latent growth mixture modeling (LGMM) was used to identify subpopulations in the Korea…

  3. Food deprivation enhances both autoshaping and autoshaping impairment by a latent inhibition procedure.

    Science.gov (United States)

    Sparber, S B; Bollweg, G L; Messing, R B

    1991-02-01

    The influence of food deprivation on acquisition of autoshaped operant behavior was measured. In one study separate groups of young, male rats that were deprived to 75%, 80%, 85%, 90%, and 95% of ad lib weight were subjected to an autoshaping procedure in which a 6 s delay was interposed between lever retraction (which occurred when rats made a lever touch, or automatically after 15 s) and food pellet delivery. In a second study, groups of rats were deprived to 80% or 90% of ad lib weight prior to testing in a latent inhibition variation of the same autoshaping procedure. This was done to determine if greater food deprivation would enhance learning which, because of the latent inhibition manipulation, is manifest as less lever-directed behavior. Greater food deprivation was associated both with fast acquisition of autoshaped lever responding and with more reliable failure to increase lever responding in the latent inhibition paradigm. Thus, increasing food deprivation was associated with enhanced acquisition regardless of whether the required performance was an increase or a failure to increase the same behavior, indicating a specific effect on learning. Copyright © 1991. Published by Elsevier B.V.

  4. Development of 101 Gene-based Single Nucleotide Polymorphism Markers in Sea Cucumber, <em>Apostichopus japonicusem>>

    Directory of Open Access Journals (Sweden)

    Wei Lu

    2012-06-01

    Full Text Available Single nucleotide polymorphisms (SNPs are currently the marker of choice in a variety of genetic studies. Using the high resolution melting (HRM genotyping approach, 101 gene-based SNP markers were developed for <em>Apostichopus japonicusem>, a sea cucumber species with economic significance for the aquaculture industry in East Asian countries. HRM analysis revealed that all the loci showed polymorphisms when evaluated using 40 <em>A. japonicusem> individuals collected from a natural population. The minor allele frequency ranged from 0.035 to 0.489. The observed and expected heterozygosities ranged from 0.050 to 0.833 and 0.073 to 0.907, respectively. Thirteen loci were found to depart significantly from Hardy–Weinberg equilibrium (HWE after Bonferroni corrections. Significant linkage disequilibrium (LD was detected in one pair of markers. These SNP markers are expected to be useful for future quantitative trait loci (QTL analysis, and to facilitate marker-assisted selection (MAS in <em>A. japonicusem>.

  5. 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

  6. 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…

  7. Investigation of Mediational Processes Using Parallel Process Latent Growth Curve Modeling

    Science.gov (United States)

    Cheong, JeeWon; MacKinnon, David P.; Khoo, Siek Toon

    2010-01-01

    This study investigated a method to evaluate mediational processes using latent growth curve modeling. The mediator and the outcome measured across multiple time points were viewed as 2 separate parallel processes. The mediational process was defined as the independent variable influencing the growth of the mediator, which, in turn, affected the growth of the outcome. To illustrate modeling procedures, empirical data from a longitudinal drug prevention program, Adolescents Training and Learning to Avoid Steroids, were used. The program effects on the growth of the mediator and the growth of the outcome were examined first in a 2-group structural equation model. The mediational process was then modeled and tested in a parallel process latent growth curve model by relating the prevention program condition, the growth rate factor of the mediator, and the growth rate factor of the outcome. PMID:20157639

  8. Latent Autoimmune Diabetes of the Adult (LADA in a Brazilian Indian

    Directory of Open Access Journals (Sweden)

    João Paulo Botelho Vieira Filho

    Full Text Available CONTEXT: Latent autoimmune diabetes of the adult (LADA as originally described represents perhaps as many as 10 -- 20% of adult-onset patients with diabetes. DESIGN: case report. CASE REPORT: A 38-year-old Brazilian Xavante-Jê Indian with Latent Autoimmune Diabetes of the Adult (LADA is described, coming from the Sangradouro community in Poxoréu, Mato Grosso. The onset of diabetes after reaching 25 years of age, the evolution to insulin deficiency after a period of insulin-independence and the presence of auto-antibodies to glutamic acid decarboxylase (GAD characteristic of LADA were present. This patient may represent the first case of LADA in a Brazilian with full Indian heritage. Further studies are necessary to verify the prevalence of this new type of diabetes in this population that does not have Caucasoid admixture and has a particular environmental background.

  9. Mixture Item Response Theory-MIMIC Model: Simultaneous Estimation of Differential Item Functioning for Manifest Groups and Latent Classes

    Science.gov (United States)

    Bilir, Mustafa Kuzey

    2009-01-01

    This study uses a new psychometric model (mixture item response theory-MIMIC model) that simultaneously estimates differential item functioning (DIF) across manifest groups and latent classes. Current DIF detection methods investigate DIF from only one side, either across manifest groups (e.g., gender, ethnicity, etc.), or across latent classes…

  10. Activity-Guided Isolation of Antioxidant Compounds from <em>Rhizophora apiculataem>

    Directory of Open Access Journals (Sweden)

    Hongbin Xiao

    2012-09-01

    Full Text Available <em>Rhizophora apiculataem> (<em>R. apiculataem> contains an abundance of biologically active compounds due its special salt-tolerant living surroundings. In this study, the total phenolic content and antioxidant activities of various extract and fractions of stem of <em>R. apiculataem> were investigated. Results indicated that butanol fraction possesses the highest total phenolic content (181.84 mg/g GAE/g dry extract with strongest antioxidant abilities. Following <em>in vitroem> antioxidant activity-guided phytochemical separation procedures, lyoniresinol-3α-<em>O>-β-arabinopyranoside (1, lyoniresinol-3α-<em>O>-β-rhamnoside (2, and afzelechin-3-<em>O>-L-rhamno-pyranoside (3 were separated from the butanol fraction. These compounds showed more noticeable antioxidant activity than a BHT standard in the DPPH, ABTS and hydroxyl radical scavenging assays. HPLC analysis results showed that among different plant parts, the highest content of 13 was located in the bark (0.068%, 0.066% and 0.011%, respectively. The results imply that the <em>R. apiculataem> might be a potential source of natural antioxidants and 13 are antioxidant ingredients in <em>R. apiculataem>.

  11. Synthesis and Spectroscopic Analysis of Novel 1<em>H-Benzo[d>]imidazoles Phenyl Sulfonylpiperazines

    Directory of Open Access Journals (Sweden)

    Amjad M. Qandil

    2012-05-01

    Full Text Available A group of benzimidazole analogs of sildenafil, 3-benzimidazolyl-4-methoxy-phenylsulfonylpiperazines 2–4 and 3-benzimidazolyl-4-methoxy-<em>N,N>-dimethyl- benzenesulfonamide (5, were efficiently synthesized. Compounds 2–5 were characterized by NMR and MS and contrary to the reported mass spectra of sildenafil, the spectra of the piperazine-containing compounds 2–4 showed a novel fragmentation pattern leading to an <em>m/z> = 316. A mechanism for the formation of this fragment was proposed.

  12. 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......), the aim of this study was to explore and descriptively compare the application of LCA when using questionnaire summary scores and when using single items to subgrouping of patients based on multidimensional data. MATERIALS AND METHODS: Baseline data from 928 LBP patients in an observational study were...

  13. Osservazioni in cattività sul ciclo stagionale del peso corporeo e sull'efficienza digestiva di <em>Pipistrellus kuhliiem> e <em>Hypsugo saviiem> (Chiroptera: Verspertilionidae

    Directory of Open Access Journals (Sweden)

    Gianna Dondini

    2004-06-01

    Full Text Available Abstract Captivity observation on body weight cycle and digestive efficiency in <em>Pipistrellus kuhliiem> and <em>Hypsugo saviiem> (Chiroptera: Vespertilionidae Many bat species of cold-temperate climate are subject to seasonal variation of temperature and food availability. Fat reserve during summer-autumn is therefore a physiological adaptation to spend the winter months by hibernating or to sustain migration. During a research on bats in urban areas, two juveniles of Kuhl's bat (<em>Pipistrellus kuhliiem>, 2 females and two juveniles of Savi's bat (<em>Hypsugo saviiem>, 1 male and 1 female were collected in 1997 in the urban area of Florence (central Italy. Bats were kept in a cage of 50x40x30 cm with a temperature between 17° and 22° C. Every day they were weighted with an electronic balance before eating mealworms (<em>Tenebrio molitorem>. Digestive efficiency, calculated on dry material, was about 90% for both species. In about six months <em>P. kuhliiem> and <em>H. saviiem> increased on the average of 450% and 280% in weight respectively. Deposition of fat reserve seemed to be faster in <em>P. kuhliiem> than in <em>H. saviiem>. Both species showed a circannual cycle in the variation of weight. Riassunto Molte specie di pipistrelli dei climi temperato-freddi sono soggette a marcate variazioni stagionali di temperatura e disponibilità di cibo. L'accumulo di grasso in tarda estate-autunno è quindi un adattamento fisiologico per trascorrere in ibernazione i mesi invernali o per intraprendere la migrazione. Nell'ambito di una ricerca pluriennale sui pipistrelli in ambienti urbani, 4 esemplari giovani, di cui 2 di Pipistrello albolimbato (<em>Pipistrellus kuhliiem>, 2 femmine e due di Pipistrello di Savi (<em>Hypsugo saviiem>, 1 maschio e 1 femmina, sono stati raccolti nella pianura di Firenze durante l'estate del 1997 e mantenuti in un contenitore di 50x40x30 cm ad

  14. Use of latent variables representing psychological motivation to explore citizens’ intentions with respect to congestion charging reform in Jakarta

    Directory of Open Access Journals (Sweden)

    Sugiarto Sugiarto

    2015-01-01

    Full Text Available The aim of this paper is to investigate the intentions of Jakarta citizens with respect to the electronic road pricing (ERP reform proposed by the city government. Utilizing data from a stated preference survey conducted in 2013, we construct six variables representing latent psychological motivations (appropriateness of ERP adoption; recognition that ERP can mitigate congestion and improve the environment; car dependency (CDC; awareness of the problems of cars in society; inhibition of freedom movement caused by ERP; and doubts about the ability of ERP to mitigate congestion and environment problems. A multiple-indicators multiple-causes (MIMIC model is developed to investigate the effects of respondents’ socio-demographics (causes on the latent constructs in order to gain better understanding of the relationship between respondents’ intentions and the observed individual’s responses (indicators obtained from the stated preference survey. The MIMIC model offers a good account of whether and how socio-demographic attributes and individual indicators predict the latent variables of psychological motivation constructs. Then, we further verify the influences of the latent variables, combining them with levy rate patterns and daily mobility attributes to investigate significant determining factors for social acceptance of the ERP proposal. A latent variable representations based on the generalized ordered response model are employed in our investigations to allow more flexibility in parameter estimation across outcomes. The results confirm that there is a strong correlation between latent psychological motivations and daily mobility attributes and the level of social acceptance for the ERP proposal. This empirical investigation demonstrates that the latent variables play more substantial role in determining scheme’s acceptance. Moreover, elasticity measures show that latent attributes are more sensitive compared to levies and daily mobility

  15. Targeting the latent cytomegalovirus reservoir with an antiviral fusion toxin protein

    DEFF Research Database (Denmark)

    Krishna, B A; Spiess, K; Poole, E L

    2017-01-01

    Reactivation of human cytomegalovirus (HCMV) in transplant recipients can cause life-threatening disease. Consequently, for transplant recipients, killing latently infected cells could have far-reaching clinical benefits. In vivo, myeloid cells and their progenitors are an important site of HCMV ...

  16. Latent human error analysis and efficient improvement strategies by fuzzy TOPSIS in aviation maintenance tasks.

    Science.gov (United States)

    Chiu, Ming-Chuan; Hsieh, Min-Chih

    2016-05-01

    The purposes of this study were to develop a latent human error analysis process, to explore the factors of latent human error in aviation maintenance tasks, and to provide an efficient improvement strategy for addressing those errors. First, we used HFACS and RCA to define the error factors related to aviation maintenance tasks. Fuzzy TOPSIS with four criteria was applied to evaluate the error factors. Results show that 1) adverse physiological states, 2) physical/mental limitations, and 3) coordination, communication, and planning are the factors related to airline maintenance tasks that could be addressed easily and efficiently. This research establishes a new analytic process for investigating latent human error and provides a strategy for analyzing human error using fuzzy TOPSIS. Our analysis process complements shortages in existing methodologies by incorporating improvement efficiency, and it enhances the depth and broadness of human error analysis methodology. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  17. A new method of artificial latent fingerprint creation using artificial sweat and inkjet printer.

    Science.gov (United States)

    Hong, Sungwook; Hong, Ingi; Han, Aleum; Seo, Jin Yi; Namgung, Juyoung

    2015-12-01

    In order to study fingerprinting in the field of forensic science, it is very important to have two or more latent fingerprints with identical chemical composition and intensity. However, it is impossible to obtain identical fingerprints, in reality, because fingerprinting comes out slightly differently every time. A previous research study had proposed an artificial fingerprint creation method in which inkjet ink was replaced with amino acids and sodium chloride solution: the components of human sweat. But, this method had some drawbacks: divalent cations were not added while formulating the artificial sweat solution, and diluted solutions were used for creating weakly deposited latent fingerprint. In this study, a method was developed for overcoming the drawbacks of the methods used in the previous study. Several divalent cations were added in this study because the amino acid-ninhydrin (or some of its analogues) complex is known to react with divalent cations to produce a photoluminescent product; and, similarly, the amino acid-1,2-indanedione complex is known to be catalyzed by a small amount of zinc ions to produce a highly photoluminescent product. Also, in this study, a new technique was developed which enables to adjust the intensity when printing the latent fingerprint patterns. In this method, image processing software is used to control the intensity of the master fingerprint patterns, which adjusts the printing intensity of the latent fingerprints. This new method opened the way to produce a more realistic artificial fingerprint in various strengths with one artificial sweat working solution. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  18. Do gamblers eat more salt? Testing a latent trait model of covariance in consumption.

    Science.gov (United States)

    Goodwin, Belinda C; Browne, Matthew; Rockloff, Matthew; Donaldson, Phillip

    2015-09-01

    A diverse class of stimuli, including certain foods, substances, media, and economic behaviours, may be described as 'reward-oriented' in that they provide immediate reinforcement with little initial investment. Neurophysiological and personality concepts, including dopaminergic dysfunction, reward sensitivity and rash impulsivity, each predict the existence of a latent behavioural trait that leads to increased consumption of all stimuli in this class. Whilst bivariate relationships (co-morbidities) are often reported in the literature, to our knowledge, a multivariate investigation of this possible trait has not been done. We surveyed 1,194 participants (550 male) on their typical weekly consumption of 11 types of reward-oriented stimuli, including fast food, salt, caffeine, television, gambling products, and illicit drugs. Confirmatory factor analysis was used to compare models in a 3×3 structure, based on the definition of a single latent factor (none, fixed loadings, or estimated loadings), and assumed residual covariance structure (none, a-priori / literature based, or post-hoc / data-driven). The inclusion of a single latent behavioural 'consumption' factor significantly improved model fit in all cases. Also confirming theoretical predictions, estimated factor loadings on reward-oriented indicators were uniformly positive, regardless of assumptions regarding residual covariances. Additionally, the latent trait was found to be negatively correlated with the non-reward-oriented indicators of fruit and vegetable consumption. The findings support the notion of a single behavioural trait leading to increased consumption of reward-oriented stimuli across multiple modalities. We discuss implications regarding the concentration of negative lifestyle-related health behaviours.

  19. Crystallization and preliminary crystallographic analysis of latent, active and recombinantly expressed aurone synthase, a polyphenol oxidase, from Coreopsis grandiflora

    Energy Technology Data Exchange (ETDEWEB)

    Molitor, Christian; Mauracher, Stephan Gerhard; Rompel, Annette, E-mail: annette.rompel@univie.ac.at [Universität Wien, Althanstrasse 14, 1090 Wien (Austria)

    2015-05-22

    Latent and active aurone synthase purified from petals of C. grandiflora (cgAUS1) were crystallized. The crystal quality of recombinantly expressed latent cgAUS1 was significantly improved by co-crystallization with the polyoxotungstate Na{sub 6}[TeW{sub 6}O{sub 24}] within the liquid–liquid phase-separation zone. Aurone synthase (AUS), a member of a novel group of plant polyphenol oxidases (PPOs), catalyzes the oxidative conversion of chalcones to aurones. Two active cgAUS1 (41.6 kDa) forms that differed in the level of phosphorylation or sulfation as well as the latent precursor form (58.9 kDa) were purified from the petals of Coreopsis grandiflora. The differing active cgAUS1 forms and the latent cgAUS1 as well as recombinantly expressed latent cgAUS1 were crystallized, resulting in six different crystal forms. The active forms crystallized in space groups P2{sub 1}2{sub 1}2{sub 1} and P12{sub 1}1 and diffracted to ∼1.65 Å resolution. Co-crystallization of active cgAUS1 with 1,4-resorcinol led to crystals belonging to space group P3{sub 1}21. The crystals of latent cgAUS1 belonged to space group P12{sub 1}1 and diffracted to 2.50 Å resolution. Co-crystallization of recombinantly expressed pro-AUS with the hexatungstotellurate(VI) salt Na{sub 6}[TeW{sub 6}O{sub 24}] within the liquid–liquid phase separation zone significantly improved the quality of the crystals compared with crystals obtained without hexatungstotellurate(VI)

  20. Assessing DSM-5 latent subtypes of acute stress disorder dissociative or intrusive?

    Science.gov (United States)

    Armour, Cherie; Hansen, Maj

    2015-02-28

    Acute Stress Disorder (ASD) was first included in the DSM-IV in 1994. It was proposed to account for traumatic responding in the early post trauma phase and to act as an identifier for later Posttraumatic Stress Disorder (PTSD). Unlike PTSD it included a number of dissociative indicators. The revised DSM-5 PTSD criterion included a dissociative-PTSD subtype. The current study assessed if a dissociative-ASD subtype may be present for DSM-5 ASD. Moreover, we assessed if a number of risk factors resulted in an increased probability of membership in symptomatic compared to a baseline ASD profile. We used data from 450 bank robbery victims. Latent profile analysis (LPA) was used to uncover latent profiles of ASD. Multinomial logistic regression was used to determine if female gender, age, social support, peritraumatic panic, somatization, and number of trauma exposures increased or decreased the probability of profile membership. Four latent profiles were uncovered and included an intrusion rather than dissociative subtype. Increased age and social support decreased the probability of individuals being grouped into the intrusion subtype whereas increased peritraumatic panic and somatization increased the probability of individuals being grouped into the intrusion subtype. Findings are discussed in regard to the ICD-11 and the DSM-5. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  1. Visualization of latent fingerprints beneath opaque electrical tapes by optical coherence tomography

    Science.gov (United States)

    Liu, Kangkang; Zhang, Ning; Meng, Li; Li, Zhigang; Xu, Xiaojing

    2018-03-01

    Electrical tape is found as one type of important trace evidence in crime scene. For example, it is very frequently used to insulate wires in explosive devices in many criminal cases. The fingerprints of the suspects were often left on the adhesive side of the tapes, which can provide very useful clues for the investigation and make it possible for individual identification. The most commonly used method to detect and visualize those latent fingerprints is to peel off each layer of the tapes first and then adopt the chemical methods to develop the fingerprints on the tapes. However, the peeling-off and chemical development process would degrade and contaminate the fingerprints and thus adversely affect the accuracy of identification. Optical coherence tomography (OCT) is a novel forensic imaging modality based on lowcoherence interferometry, which has the advantages of non-destruction, micrometer-level high resolution and crosssectional imaging. In this study, a fiber-based spectral-domain OCT (SD-OCT) system with {6μm resolution was employed to obtain the image of fingerprint sandwiched between two opaque electrical tapes without any pre-processing procedure like peeling-off. Three-dimensional (3D) OCT reconstruction was performed and the subsurface image was produced to visualize the latent fingerprints. The results demonstrate that OCT is a promising tool for recovering the latent fingerprints hidden beneath opaque electrical tape non-destructively and rapidly.

  2. Modelo matemático para previsão da produtividade do cafeeiro

    Directory of Open Access Journals (Sweden)

    José M. Miranda

    2014-04-01

    Full Text Available Objetivou-se, com este trabalho, a criação de um modelo matemático, prático e eficiente para a previsão antecipada de safras com base em alguns atributos fenológicos da planta: altura, número de frutos no 4º e 5º internódios dos ramos plagiotrópicos, comprimento em metros das linhas de café e diâmetro medido na região inferior das plantas. O experimento foi montado nos cafezais do IFSULDEMINAS - Campus Machado, em que quatro cultivares de diferentes portes tiveram sua produtividade analisada durante a safra 2010/2011: Catucaí, Mundo Novo, Rubi e Topázio, cada uma se constituiu em unidade experimental na qual, por sua vez, foram amostradas 10 plantas aleatoriamente sendo 6 ramos amostrados em cada planta (três do lado do sol nascente e três do lado do sol poente, sendo dois no terço superior, outros dois na região intermediária e os dois últimos na região inferior de cada planta. Os dados foram colhidos no final do mês de fevereiro de 2011. O modelo que considera a proporção do volume de copa do cafeeiro tentando aproximar-se mais da arquitetura real da planta foi o mais significativo apresentando coeficiente de determinação de 0,83.

  3. HYBRID INDIRECT SOLAR COOKER WITH LATENT HEAT STORAGE

    OpenAIRE

    Benazeer Hassan K. Ibrahim *, Victor Jose

    2016-01-01

    Solar cooking is the simplest, safest, most convenient way to cook food without consuming fuels or heating up the kitchen. All the conventional solar cooker designs have the disadvantage of inability to cook during off-shine and night hours.This disadvantage can be eliminated if the solar cooker is designed with thermal storage arrangement. In this paper, a hybrid solar cooker with evacuated tube collector and latent thermal storage unit and alternate electric heatingsource is simulated. The...

  4. 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…

  5. Reversible enlargement of the hypophysis in clinically latent hypothyroidism

    Energy Technology Data Exchange (ETDEWEB)

    Schuemichen, C.

    1982-12-01

    A case is reported, in which the combination of high TT/sub 3/- and FT/sub 4/ plasma levels, increased TSH basal secretion and enlargement of the pituitary gland did not reflect secondary hyperthyroidism, but was cuased by clinically latent hypothyroidism, probably due to thyroid hormone antibodies. High doses of thyroid hormones lowered the TSH and prolactin basal secretion, and reduced the enlargement of the pituitary gland.

  6. Reversible enlargement of the hypophysis in clinically latent hypothyroidism

    International Nuclear Information System (INIS)

    Schuemichen, C.

    1982-01-01

    A case is reported, in which the combination of high TT 3 - and FT 4 plasma levels, increased TSH basal secretion and enlargement of the pituitary gland did not reflect secondary hyperthyroidism, but was cuased by clinically latent hypothyroidism, probably due to thyroid hormone antibodies. High doses of thyroid hormones lowered the TSH and prolactin basal secretion, and reduced the enlargement of the pituitary gland. (orig.) [de

  7. The Blind Men and the Elephant: Identification of a Latent Maltreatment Construct for Youth in Foster Care

    Science.gov (United States)

    Gabrielli, Joy; Jackson, Yo; Tunno, Angela M.; Hambrick, Erin P.

    2017-01-01

    Child maltreatment is a major public health concern due to its impact on developmental trajectories and consequences across mental and physical health outcomes. Operationalization of child maltreatment has been complicated, as research has used simple dichotomous counts to identification of latent class profiles. This study examines a latent measurement model assessed within foster youth inclusive of indicators of maltreatment chronicity and severity across four maltreatment types: physical, sexual, and psychological abuse, and neglect. Participants were 500 foster youth with a mean age of 12.99 years (SD = 2.95 years). Youth completed survey questions through a confidential audio computer-assisted self-interview program. A two-factor model with latent constructs of chronicity and severity of maltreatment revealed excellent fit across fit indices; however, the latent constructs were correlated .972. A one-factor model also demonstrated excellent model fit to the data (χ2 (16, n = 500) =28.087, p =.031, RMSEA (0.012 – 0.062) =.039, TLI =.990, CFI =.994, SRMR =.025) with a nonsignificant chi-square difference test comparing the one- and two-factor models. Invariance tests across age, gender, and placement type also were conducted with recommendations provided. Results suggest a single-factor latent model of maltreatment severity and chronicity can be attained. Thus, the maltreatment experiences reported by foster youth, though varied and complex, were captured in a model that may prove useful in later predictions of outcome behaviors. Appropriate identification of both the chronicity and severity of maltreatment inclusive of the range of maltreatment types remains a high priority for future research. PMID:28254690

  8. An Optimized DNA Analysis Workflow for the Sampling, Extraction, and Concentration of DNA obtained from Archived Latent Fingerprints.

    Science.gov (United States)

    Solomon, April D; Hytinen, Madison E; McClain, Aryn M; Miller, Marilyn T; Dawson Cruz, Tracey

    2018-01-01

    DNA profiles have been obtained from fingerprints, but there is limited knowledge regarding DNA analysis from archived latent fingerprints-touch DNA "sandwiched" between adhesive and paper. Thus, this study sought to comparatively analyze a variety of collection and analytical methods in an effort to seek an optimized workflow for this specific sample type. Untreated and treated archived latent fingerprints were utilized to compare different biological sampling techniques, swab diluents, DNA extraction systems, DNA concentration practices, and post-amplification purification methods. Archived latent fingerprints disassembled and sampled via direct cutting, followed by DNA extracted using the QIAamp® DNA Investigator Kit, and concentration with Centri-Sep™ columns increased the odds of obtaining an STR profile. Using the recommended DNA workflow, 9 of the 10 samples provided STR profiles, which included 7-100% of the expected STR alleles and two full profiles. Thus, with carefully selected procedures, archived latent fingerprints can be a viable DNA source for criminal investigations including cold/postconviction cases. © 2017 American Academy of Forensic Sciences.

  9. Vertical Profiles of Latent Heat Release over the Global Tropics using TRMM Rainfall Products from December 1997 to November 2002

    Science.gov (United States)

    Tao, W.-K.; Lang, S.; Simpson, J.; Meneghini, R.; Halverson, J.; Johnson, R.; Adler, R.

    2003-01-01

    NASA Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) derived rainfall information will be used to estimate the four-dimensional structure of global monthly latent heating and rainfall profiles over the global tropics from December 1997 to November 2000. Rainfall, latent heating and radar reflectivity structures between El Nino (DJF 1997-98) and La Nina (DJF 1998-99) will be examined and compared. The seasonal variation of heating over various geographic locations (i.e., oceanic vs continental, Indian ocean vs west Pacific, Africa vs. S. America ) will also be analyzed. In addition, the relationship between rainfall, latent heating (maximum heating level), radar reflectivity and SST is examined and will be presented in the meeting. The impact of random error and bias in stratiform percentage estimates from PR on latent heating profiles is studied and will also be presented in the meeting. The Goddard Cumulus Ensemble Model is being used to simulate various mesoscale convective systems that developed in different geographic locations. Specifically, the model estimated rainfall, radar reflectivity and latent heating profiles will be compared to observational data collected from TRMM field campaigns over the South China Sea in 1998 (SCSMEX), Brazil in 1999 (TRMM-LBA), and the central Pacific in 1999 (KWAJEX). Sounding diagnosed heating budgets and radar reflectivity from these experiments can provide the means to validate (heating product) as well as improve the GCE model. Review of other latent heating algorithms will be discussed in the workshop.

  10. Prevalence Estimation and Validation of New Instruments in Psychiatric Research: An Application of Latent Class Analysis and Sensitivity Analysis

    Science.gov (United States)

    Pence, Brian Wells; Miller, William C.; Gaynes, Bradley N.

    2009-01-01

    Prevalence and validation studies rely on imperfect reference standard (RS) diagnostic instruments that can bias prevalence and test characteristic estimates. The authors illustrate 2 methods to account for RS misclassification. Latent class analysis (LCA) combines information from multiple imperfect measures of an unmeasurable latent condition to…

  11. Measuring what latent fingerprint examiners consider sufficient information for individualization determinations.

    Directory of Open Access Journals (Sweden)

    Bradford T Ulery

    Full Text Available Latent print examiners use their expertise to determine whether the information present in a comparison of two fingerprints (or palmprints is sufficient to conclude that the prints were from the same source (individualization. When fingerprint evidence is presented in court, it is the examiner's determination--not an objective metric--that is presented. This study was designed to ascertain the factors that explain examiners' determinations of sufficiency for individualization. Volunteer latent print examiners (n = 170 were each assigned 22 pairs of latent and exemplar prints for examination, and annotated features, correspondence of features, and clarity. The 320 image pairs were selected specifically to control clarity and quantity of features. The predominant factor differentiating annotations associated with individualization and inconclusive determinations is the count of corresponding minutiae; other factors such as clarity provided minimal additional discriminative value. Examiners' counts of corresponding minutiae were strongly associated with their own determinations; however, due to substantial variation of both annotations and determinations among examiners, one examiner's annotation and determination on a given comparison is a relatively weak predictor of whether another examiner would individualize. The extensive variability in annotations also means that we must treat any individual examiner's minutia counts as interpretations of the (unknowable information content of the prints: saying "the prints had N corresponding minutiae marked" is not the same as "the prints had N corresponding minutiae." More consistency in annotations, which could be achieved through standardization and training, should lead to process improvements and provide greater transparency in casework.

  12. Generalized reduced rank latent factor regression for high dimensional tensor fields, and neuroimaging-genetic applications.

    Science.gov (United States)

    Tao, Chenyang; Nichols, Thomas E; Hua, Xue; Ching, Christopher R K; Rolls, Edmund T; Thompson, Paul M; Feng, Jianfeng

    2017-01-01

    We propose a generalized reduced rank latent factor regression model (GRRLF) for the analysis of tensor field responses and high dimensional covariates. The model is motivated by the need from imaging-genetic studies to identify genetic variants that are associated with brain imaging phenotypes, often in the form of high dimensional tensor fields. GRRLF identifies from the structure in the data the effective dimensionality of the data, and then jointly performs dimension reduction of the covariates, dynamic identification of latent factors, and nonparametric estimation of both covariate and latent response fields. After accounting for the latent and covariate effects, GRLLF performs a nonparametric test on the remaining factor of interest. GRRLF provides a better factorization of the signals compared with common solutions, and is less susceptible to overfitting because it exploits the effective dimensionality. The generality and the flexibility of GRRLF also allow various statistical models to be handled in a unified framework and solutions can be efficiently computed. Within the field of neuroimaging, it improves the sensitivity for weak signals and is a promising alternative to existing approaches. The operation of the framework is demonstrated with both synthetic datasets and a real-world neuroimaging example in which the effects of a set of genes on the structure of the brain at the voxel level were measured, and the results compared favorably with those from existing approaches. Copyright © 2016. Published by Elsevier Inc.

  13. Glycosylation of Vanillin and 8-Nordihydrocapsaicin by Cultured <em>Eucalyptus perrinianaem> Cells

    Directory of Open Access Journals (Sweden)

    Naoji Kubota

    2012-05-01

    Full Text Available Glycosylation of vanilloids such as vanillin and 8-nordihydrocapsaicin by cultured plant cells of <em>Eucalyptus perrinianaem> was studied. Vanillin was converted into vanillin 4-<em>O>-b-D-glucopyranoside, vanillyl alcohol, and 4-<em>O>-b-D-glucopyranosylvanillyl alcohol by <em>E. perriniana em>cells. Incubation of cultured <em>E. perrinianaem> cells with 8-nor- dihydrocapsaicin gave 8-nordihydrocapsaicin 4-<em>O>-b-D-glucopyranoside and 8-nordihydro- capsaicin 4-<em>O>-b-D-gentiobioside.

  14. Personality types in childhood: relations to latent trajectory classes of problem behavior and overreactive parenting across the transition into adolescence

    NARCIS (Netherlands)

    van den Akker, A.L.; Deković, M.; Asscher, J.J.; Shiner, R.L.; Prinzie, P.

    2013-01-01

    This study investigated relations among children's personality types, trajectories of internalizing and externalizing problems, and overreactive parenting across 6 years. Latent Class Analysis of the Big 5 personality dimensions (modeled as latent factors, based on mother, father and teacher

  15. Distinct ontogenic patterns of overt and latent DGAT activities of rat liver microsomes.

    Science.gov (United States)

    Waterman, Ian J; Price, Nigel T; Zammit, Victor A

    2002-09-01

    We have studied the ontogeny of the two functional diacylglycerol acyltransferase (DGAT) activities (overt and latent) during postnatal development in rat liver. We find that the ontogenic patterns of the two are highly distinct. Overt DGAT shows a transient rise in activity up to day 4 postnatally, after which it declines until weaning; thereafter, it increases steadily to reach high adult values that may contribute to the high rates of turnover of cytosolic triacylglycerol (TAG). By contrast, latent DGAT activity increases continuously during the suckling period but falls sharply upon weaning onto chow but not onto a high-fat diet. Rates of TAG secretion by hepatocytes are higher than in the adult during the first 7 days after birth, and are largely dependent on the mobilization of the abundant intrahepatocyte TAG as a source of acyl moieties. When the hepatic steatosis is cleared (after day 7) the TAG secretion rate declines by 80% to reach adult values. Quantification of the content of mRNA for the DGAT1 and DGAT2 genes does not show correlation with either of the DGAT activities. We conclude that post-translational modification may play an important role in the overt and latent distribution of DGAT activity in the liver microsomal membrane.

  16. Realizing the Latent Potential in the Part-Time Student Workforce

    Science.gov (United States)

    Evans, Carl; Richardson, Mark

    2016-01-01

    The purpose of this article is to challenge employers to make the best use of the latent potential of their part-time student workforce and to retain this talent postgraduation. The authors report research which shows that increasing numbers of university students are working part-time alongside their degree studies, while at the same time…

  17. Cyclist–motorist crash patterns in Denmark: A latent class clustering approach

    DEFF Research Database (Denmark)

    Kaplan, Sigal; Prato, Carlo Giacomo

    2013-01-01

    to prioritize safety issues and to devise efficient preventive measures. Method: The current study focused on cyclist–motorist crashes that occurred in Denmark during the period between 2007 and 2011. To uncover crash patterns, the current analysis applied latent class clustering, an unsupervised probabilistic...

  18. Efficiency gains of photovoltaic system using latent heat thermal energy storage

    NARCIS (Netherlands)

    Tan, Lippong; Date, Abhijit; Fernandes, Gabriel; Singh, Baljit; Ganguly, Sayantan

    This paper presents experimental assessments of the thermal and electrical performance of photovoltaic (PV) system by comparing the latent heat-cooled PV panel with the naturally-cooled equivalent. It is commonly known that the energy conversion efficiency of the PV cells declines with the increment

  19. 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).

  20. Fitoextração de sais pela Atriplex nummularia lindl. sob estresse hídrico em solo salino sódico Phytoextraction of salts by Atriplex nummularia lindl. under water stress in saline sodic soils

    Directory of Open Access Journals (Sweden)

    Edivan R. de Souza

    2011-05-01

    Full Text Available Objetivou-se avaliar a extração de sais pela Atriplex cultivada em solo salino sódico sob condições de estresse hídrico e comparar propriedades do solo antes e após seu cultivo. O experimento foi desenvolvido em casa de vegetação durante 134 dias, com cultivo em vasos com 20 kg de solo salino sódico em quatro níveis de umidade (35, 55, 75 e 95% da capacidade de campo, com um tratamento controle (sem cultivo, montado em blocos casualizados, com oito repetições. As altas concentrações de Ca2+, Mg2+, K+ e, especialmente Na+ e Cl- nas folhas de Atriplex nummularia, associadas à elevada produção de massa seca, caracterizam esta espécie como planta fitoextratora de sais, chegando a extrair, nas folhas e caule, o equivalente a: 644,25; 757,81; 1.058,55 e 1.182,00 kg ha-1 desses elementos, para 35, 55, 75 e 95% da capacidade de campo, respectivamente. As variáveis do complexo sortivo do solo (Ca2+, Mg2+, K+, soma de bases e o carbono orgânico total, permaneceram estáveis entre o início e o final do experimento, em todos os tratamentos, enquanto o Na+ e a percentagem de sódio trocável diminuíram após o cultivo da planta. A Atriplex respondeu ao incremento de umidade do solo quando se considera a produção de biomassa e a extração de sais.This study aims to evaluate the growth, production and extraction of salts by Atriplex grown on saline-sodic soil under water stress conditions and to compare soil properties before and after their cultivation. The experiment was carried out in a greenhouse during 134 days growing Atriplex nummularia in pots with 20 kg of saline sodic soil with four levels of soil moisture (35, 55, 75 and 95% of field capacity with a control (soil without plant. The experiment was performed in a randomized block with eight replications. The high concentrations of Ca2+, Mg2+, K+, and especially Na+ and Cl- in leaves of Atriplex nummularia, associated with high dry matter production characterizes this species

  1. STARD-BLCM: Standards for the Reporting of Diagnostic accuracy studies that use Bayesian Latent Class Models

    DEFF Research Database (Denmark)

    Kostoulas, Polychronis; Nielsen, Søren S.; Branscum, Adam J.

    2017-01-01

    The Standards for the Reporting of Diagnostic Accuracy (STARD) statement, which was recently updated to the STARD2015 statement, was developed to encourage complete and transparent reporting of test accuracy studies. Although STARD principles apply broadly, the checklist is limited to studies......-BLCM (Standards for Reporting of Diagnostic accuracy studies that use Bayesian Latent Class Models), will facilitate improved quality of reporting on the design, conduct and results of diagnostic accuracy studies that use Bayesian latent class models....

  2. A Probabilistic Recommendation Method Inspired by Latent Dirichlet Allocation Model

    Directory of Open Access Journals (Sweden)

    WenBo Xie

    2014-01-01

    Full Text Available The recent decade has witnessed an increasing popularity of recommendation systems, which help users acquire relevant knowledge, commodities, and services from an overwhelming information ocean on the Internet. Latent Dirichlet Allocation (LDA, originally presented as a graphical model for text topic discovery, now has found its application in many other disciplines. In this paper, we propose an LDA-inspired probabilistic recommendation method by taking the user-item collecting behavior as a two-step process: every user first becomes a member of one latent user-group at a certain probability and each user-group will then collect various items with different probabilities. Gibbs sampling is employed to approximate all the probabilities in the two-step process. The experiment results on three real-world data sets MovieLens, Netflix, and Last.fm show that our method exhibits a competitive performance on precision, coverage, and diversity in comparison with the other four typical recommendation methods. Moreover, we present an approximate strategy to reduce the computing complexity of our method with a slight degradation of the performance.

  3. The relevance of security: A latent domain of attachment relationships.

    Science.gov (United States)

    Mannarini, Stefania; Boffo, Marilisa

    2014-02-01

    In the present study an adult attachment dimension, latent to the constructs of security, anxiety, and avoidance, was hypothesized, wherein security was expected to occupy the most relevant position. Furthermore, the reciprocal functioning of attachment constructs and their interactions with self-esteem were explored. Four hundreds and thirty-four Italian university students responded to two adult attachment questionnaires (Attachment Style Questionnaire and Adult Attachment Questionnaire) and to the Rosenberg Self-esteem scale. A Many-Facet Rasch Measurement modeling approach was adopted. The main results can be summarized as follows: (a) security, anxiety, and avoidance are nested under one latent attachment dimension; (b) security occupies the most prominent position on the dimension; (c) security is positively associated with a moderate level of attachment anxiety and negatively related to avoidance; and (d) a positive interaction between self-esteem and security, and a negative relation between self-esteem and anxiety, were detected. Theoretical, clinical, and empirical implications of the results are further discussed. © 2013 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  4. Disrupted latent decision processes in medication-free pediatric OCD patients.

    Science.gov (United States)

    Erhan, Ceyla; Bulut, Gresa Çarkaxhiu; Gökçe, Sebla; Ozbas, Duru; Turkakin, Esin; Dursun, Onur Burak; Yazgan, Yanki; Balcı, Fuat

    2017-01-01

    Decision-making in Obsessive Compulsive Disorder has typically been investigated in the adult population. Computational approaches have recently started to get integrated into these studies. However, decision-making research in pediatric OCD populations is scarce. We investigated latent decision processes in 21 medication-free pediatric OCD patients and 23 healthy control participants. We hypothesized that OCD patients would be more cautious and less efficient in evidence accumulation than controls in a two alternative forced choice (2AFC) task. Pediatric OCD patients were less efficient than controls in accumulating perceptual evidence and showed a tendency to be more cautious. In comparison to post-correct decisions, OCD patients increased decision thresholds after erroneous decisions, whereas healthy controls decreased decision thresholds. These changes were coupled with weaker evidence accumulation after errors in both groups. The small sample size limited the power of the study. Our results demonstrate poorer decision-making performance in pediatric OCD patients at the level of latent processes, specifically in terms of evidence accumulation. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Dissociative features in posttraumatic stress disorder: A latent profile analysis.

    Science.gov (United States)

    Műllerová, Jana; Hansen, Maj; Contractor, Ateka A; Elhai, Jon D; Armour, Cherie

    2016-09-01

    The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) characterizes the dissociative subtype of posttraumatic stress disorder (PTSD) in terms of the individual meeting the criteria for PTSD and additionally reporting symptoms of depersonalization and/or derealization. The current study aimed to examine whether a dissociative PTSD profile may include alternative features of dissociation and whether it could be differentiated from a nondissociative PTSD profile on certain psychopathologies and demographics. Data from 309 trauma-exposed participants, collected through Amazon Mechanical Turk, were subjected to latent profile analysis. Regression analyses were used to examine the predictors of latent classes. Three discrete profiles named Baseline, PTSD, and Dissociative profile were uncovered. All examined features of dissociation were significantly elevated in the Dissociative profile. Anxiety, male sex, being employed, and having a minority racial background significantly predicted the Dissociative profile relative to the PTSD profile. The study points to the importance of alternative symptoms of dissociation in the dissociative PTSD subtype beyond the symptoms of depersonalization and derealization. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  6. Immunization against Genital Herpes with a Vaccine Virus That has Defects in Productive and Latent Infection

    Science.gov (United States)

    da Costa, Xavier J.; Jones, Cheryl A.; Knipe, David M.

    1999-06-01

    An effective vaccine for genital herpes has been difficult to achieve because of the limited efficacy of subunit vaccines and the safety concerns about live viruses. As an alternative approach, mutant herpes simplex virus strains that are replication-defective can induce protective immunity. To increase the level of safety and to prove that replication was not needed for immunization, we constructed a mutant herpes simplex virus 2 strain containing two deletion mutations, each of which eliminated viral replication. The double-mutant virus induces protective immunity that can reduce acute viral shedding and latent infection in a mouse genital model, but importantly, the double-mutant virus shows a phenotypic defect in latent infection. This herpes vaccine strain, which is immunogenic but has defects in both productive and latent infection, provides a paradigm for the design of vaccines and vaccine vectors for other sexually transmitted diseases, such as AIDS.

  7. Deregulated microRNAs in CD4+ T cells from individuals with latent tuberculosis versus active tuberculosis.

    Science.gov (United States)

    Fu, Yurong; Yi, Zhengjun; Li, Jianhua; Li, Ruifang

    2014-03-01

    The mechanisms of latent tuberculosis (TB) infection remain elusive. Roles of microRNA (miRNA) have been highlighted in pathogen-host interactions recently. To identify miRNAs involved in the immune response to TB, expression profiles of miRNAs in CD4(+) T cells from patients with latent TB, active TB and healthy controls were investigated by microarray assay and validated by RT-qPCR. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were used to analyse the significant functions and involvement in signalling pathways of the differentially expressed miRNAs. To identify potential target genes for miR-29, interferon-γ (IFN-γ) mRNA expression was measured by RT-qPCR. Our results showed that 27 miRNAs were deregulated among the three groups. RT-qPCR results were generally consistent with the microarray data. We observed an inverse correlation between miR-29 level and IFN-γ mRNA expression in CD4(+) T cells. GO and KEGG pathway analysis showed that the possible target genes of deregulated miRNAs were significantly enriched in mitogen-activated protein kinase signalling pathway, focal adhesion and extracellular matrix receptor interaction, which might be involved in the transition from latent to active TB. In all, for the first time, our study revealed that some miRNAs in CD4(+) T cells were altered in latent and active TB. Function and pathway analysis highlighted the possible involvement of miRNA-deregulated mRNAs in TB. The study might help to improve understanding of the relationship between miRNAs in CD4(+) T cells and TB, and laid an important foundation for further identification of the underlying mechanisms of latent TB infection and its reactivation. © 2013 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  8. A Comparison of Approaches for the Analysis of Interaction Effects between Latent Variables Using Partial Least Squares Path Modeling

    Science.gov (United States)

    Henseler, Jorg; Chin, Wynne W.

    2010-01-01

    In social and business sciences, the importance of the analysis of interaction effects between manifest as well as latent variables steadily increases. Researchers using partial least squares (PLS) to analyze interaction effects between latent variables need an overview of the available approaches as well as their suitability. This article…

  9. Labour management and Obstetric outcomes among pregnant women admitted in latent phase compared to active phase of labour at Bugando Medical Centre in Tanzania.

    Science.gov (United States)

    Chuma, Clotrida; Kihunrwa, Albert; Matovelo, Dismas; Mahendeka, Marietha

    2014-02-12

    Interventions given to women admitted in latent or active phase of labor may influence the outcomes of labor and ameliorate complications which can affect the mother and fetus. Labour management, maternal and fetal outcomes among low risk women presenting both in latent phase and active phase of labour in Tanzania have not recently been explored. This was a descriptive cross-sectional study. It was done from February to April 2013. Case notes were collected serially until the sample size was reached. A structured checklist was used to extract data. Data was analyzed using SPSS version 17. A p women were collected, half of each presented in latent phase and active phase of labour. Key interventions including augmentation with oxytocin, artificial rupture of membranes and caesarean section were significantly higher in the latent phase group than the active phase group 84(33.6%) versus 52(20.8%) p women admitted initially in active phase than in latent phase groups 180(72.0%), versus 153(61.2%) p > 0.01). There were more women in the active phase group who sustained genital tract tear and postpartum haemorrhage than in the latent phase group 101(18.6%), versus 38(15.6%) p women admitted at BMC in latent phase of labour are subjected to more obstetric interventions than those admitted in the active phase. There is need to produce guidelines on management of women admitted in latent phase of labour at BMC to reduce the risk of unnecessary interventions.

  10. Discovery of a small molecule agonist of phosphatidylinositol 3-kinase p110α that reactivates latent HIV-1.

    Directory of Open Access Journals (Sweden)

    Geneviève Doyon

    Full Text Available Combination antiretroviral therapy (cART can effectively suppress HIV-1 replication, but the latent viral reservoir in resting memory CD4(+ T cells is impervious to cART and represents a major barrier to curing HIV-1 infection. Reactivation of latent HIV-1 represents a possible strategy for elimination of this reservoir. In this study we describe the discovery of 1,2,9,10-tetramethoxy-7H-dibenzo[de,g]quinolin-7-one (57704 which reactivates latent HIV-1 in several cell-line models of latency (J89GFP, U1 and ACH-2. 57704 also increased HIV-1 expression in 3 of 4 CD8(+-depleted blood mononuclear cell preparations isolated from HIV-1-infected individuals on suppressive cART. In contrast, vorinostat increased HIV-1 expression in only 1 of the 4 donors tested. Importantly, 57704 does not induce global T cell activation. Mechanistic studies revealed that 57704 reactivates latent HIV-1 via the phosphatidylinositol 3-kinase (PI3K/protein kinase B (Akt signaling pathway. 57704 was found to be an agonist of PI3K with specificity to the p110α isoform, but not the p110β, δ or γ isoforms. Taken together, our work suggests that 57704 could serve as a scaffold for the development of more potent activators of latent HIV-1. Furthermore, it highlights the involvement of the PI3K/Akt pathway in the maintenance of HIV-1 latency.

  11. Preferencia alimenticia del ácaro depredador <em>Balaustium> sp. en condiciones controladas

    Directory of Open Access Journals (Sweden)

    Muñoz Karen

    2009-04-01

    Full Text Available

    Se evaluó la preferencia de presas de <em>Balaustium> sp., enemigo natural de diferentes artrópodos plaga, y el cual es nativo de la Sabana de Bogotá. En unidades experimentales construidas con foliolos de plantas de rosa se colocaron independientemente individuos de <em>Balaustium> sp. y se registró el número de presas consumidas. De esta manera se determinó la preferencia de los tres estados móviles del ácaro depredador <em>Balaustium> sp. por diferentes edades de tres presas. Las especies y edades de las presas estudiadas fueron: huevos, ninfas y adultos de <em>Trialeurodes vaporariorumem>, huevos, ninfas y adultos de <em>Tetranychus urticaeem>, y larvas de primer y segundo instar y adultos de <em>Frankliniella occidentalisem>. Los estados menos desarrollados fueron preferidos, aunque se observó que los adultos del depredador tienen gran habilidad para consumir adultos de <em>T. vaporariorumem>. La presa preferida por las larvas de <em>Balaustium> sp. fue los huevos de <em>T. urticaeem> con una proporción de consumo de 0,54 de los huevos que se ofrecieron de esta presa; las deutoninfas del depredador eligieron huevos de <em>T. vaporariorumem> (0,537 o de <em>T. urticaeem> (0,497 y los adultos de <em>Balaustium> sp. prefrieron los huevos de <em>T. vaporariorumem> (0,588.

  12. Ultrasound-Assisted Extraction of Carnosic Acid and Rosmarinic Acid Using Ionic Liquid Solution from <em>Rosmarinus officinalisem>>

    Directory of Open Access Journals (Sweden)

    Chunjian Zhao

    2012-09-01

    Full Text Available Ionic liquid based, ultrasound-assisted extraction was successfully applied to the extraction of phenolcarboxylic acids, carnosic acid and rosmarinic acid, from <em>Rosmarinus officinalisem>. Eight ionic liquids, with different cations and anions, were investigated in this work and [C8mim]Br was selected as the optimal solvent. Ultrasound extraction parameters, including soaking time, solid–liquid ratio, ultrasound power and time, and the number of extraction cycles, were discussed by single factor experiments and the main influence factors were optimized by response surface methodology. The proposed approach was demonstrated as having higher efficiency, shorter extraction time and as a new alternative for the extraction of carnosic acid and rosmarinic acid from <em>R. officinalisem>> em>compared with traditional reference extraction methods. Ionic liquids are considered to be green solvents, in the ultrasound-assisted extraction of key chemicals from medicinal plants, and show great potential.

  13. A competitive enzyme immunoassay for the quantitative detection of cocaine from banknotes and latent fingermarks.

    Science.gov (United States)

    van der Heide, Susan; Garcia Calavia, Paula; Hardwick, Sheila; Hudson, Simon; Wolff, Kim; Russell, David A

    2015-05-01

    A sensitive and versatile competitive enzyme immunoassay (cEIA) has been developed for the quantitative detection of cocaine in complex forensic samples. Polyclonal anti-cocaine antibody was purified from serum and deposited onto microtiter plates. The concentration of the cocaine antibody adsorbed onto the plates, and the dilution of the cocaine-HRP hapten were both studied to achieve an optimised immunoassay. The method was successfully used to quantify cocaine in extracts taken from both paper currency and latent fingermarks. The limit of detection (LOD) of 0.162ngmL(-1) achieved with the assay compares favourably to that of conventional chromatography-mass spectroscopy techniques, with an appropriate sensitivity for the quantification of cocaine at the low concentrations present in some forensic samples. The cEIA was directly compared to LC-MS for the analysis of ten UK banknote samples. The results obtained from both techniques were statistically similar, suggesting that the immunoassay was unaffected by cross-reactivity with potentially interfering compounds. The cEIA was used also for the detection of cocaine in extracts from latent fingermarks. The results obtained were compared to the cocaine concentrations detected in oral fluid sampled from the same individual. Using the cEIA, we have shown, for the first time, that endogeneously excreted cocaine can be detected and quantified from a single latent fingermark. Additionally, it has been shown that the presence of cocaine, at similar concentrations, in more than one latent fingermark from the same individual can be linked with those concentrations found in oral fluid. These results show that detection of drugs in latent fingermarks could directly indicate whether an individual has consumed the drug. The specificity and feasibility of measuring low concentrations of cocaine in complex forensic samples demonstrate the effectiveness and robustness of the assay. The immunoassay presents a simple and cost

  14. Genes expressed in grapevine leaves reveal latent wood infection by the fungal pathogen Neofusicoccum parvum.

    Directory of Open Access Journals (Sweden)

    Stefan Czemmel

    Full Text Available Some pathogenic species of the Botryosphaeriaceae have a latent phase, colonizing woody tissues while perennial hosts show no apparent symptoms until conditions for disease development become favorable. Detection of these pathogens is often limited to the later pathogenic phase. The latent phase is poorly characterized, despite the need for non-destructive detection tools and effective quarantine strategies, which would benefit from identification of host-based markers in leaves. Neofusicoccum parvum infects the wood of grapevines and other horticultural crops, killing the fruit-bearing shoots. We used light microscopy and high-resolution computed tomography (HRCT to examine the spatio-temporal relationship between pathogen colonization and anatomical changes in stem sections. To identify differentially-expressed grape genes, leaves from inoculated and non-inoculated plants were examined using RNA-Seq. The latent phase occurred between 0 and 1.5 months post-inoculation (MPI, during which time the pathogen did not spread significantly beyond the inoculation site nor were there differences in lesion lengths between inoculated and non-inoculated plants. The pathogenic phase occurred between 1.5 and 2 MPI, when recovery beyond the inoculation site increased and lesion lengths of inoculated plants tripled. By 2 MPI, inoculated plants also had decreased starch content in xylem fibers and rays, and increased levels of gel-occluded xylem vessels, the latter of which HRCT revealed at a higher frequency than microscopy. RNA-Seq and screening of 21 grape expression datasets identified 20 candidate genes that were transcriptionally-activated by infection during the latent phase, and confirmed that the four best candidates (galactinol synthase, abscisic acid-induced wheat plasma membrane polypeptide-19 ortholog, embryonic cell protein 63, BURP domain-containing protein were not affected by a range of common foliar and wood pathogens or abiotic stresses

  15. DNA-PK/Ku complex binds to latency-associated nuclear antigen and negatively regulates Kaposi's sarcoma-associated herpesvirus latent replication

    International Nuclear Information System (INIS)

    Cha, Seho; Lim, Chunghun; Lee, Jae Young; Song, Yoon-Jae; Park, Junsoo; Choe, Joonho; Seo, Taegun

    2010-01-01

    During latent infection, latency-associated nuclear antigen (LANA) of Kaposi's sarcoma-associated herpesvirus (KSHV) plays important roles in episomal persistence and replication. Several host factors are associated with KSHV latent replication. Here, we show that the catalytic subunit of DNA protein kinase (DNA-PKcs), Ku70, and Ku86 bind the N-terminal region of LANA. LANA was phosphorylated by DNA-PK and overexpression of Ku70, but not Ku86, impaired transient replication. The efficiency of transient replication was significantly increased in the HCT116 (Ku86 +/-) cell line, compared to the HCT116 (Ku86 +/+) cell line, suggesting that the DNA-PK/Ku complex negatively regulates KSHV latent replication.

  16. Latent variable models an introduction to factor, path, and structural equation analysis

    CERN Document Server

    Loehlin, John C

    2004-01-01

    This fourth edition introduces multiple-latent variable models by utilizing path diagrams to explain the underlying relationships in the models. The book is intended for advanced students and researchers in the areas of social, educational, clinical, ind

  17. The Multi-state Latent Factor Intensity Model for Credit Rating Transitions

    NARCIS (Netherlands)

    Koopman, S.J.; Lucas, A.; Monteiro, A.

    2008-01-01

    A new empirical reduced-form model for credit rating transitions is introduced. It is a parametric intensity-based duration model with multiple states and driven by exogenous covariates and latent dynamic factors. The model has a generalized semi-Markov structure designed to accommodate many of the

  18. Histone deacetylase inhibitors for purging HIV-1 from the latent reservoir.

    NARCIS (Netherlands)

    Matalon, S.; Rasmussen, T.A.; Dinarello, C.A.

    2011-01-01

    A reservoir of latently infected memory CD4(+) T cells is believed to be the source of HIV-1 reemergence after discontinuation of antiretroviral therapy. HIV-1 eradication may depend on depletion of this reservoir. Integrated HIV-1 is inaccessible for expression, in part because of histone

  19. On the Integrity of Online Testing for Introductory Statistics Courses: A Latent Variable Approach

    Directory of Open Access Journals (Sweden)

    Alan Fask

    2015-04-01

    Full Text Available There has been a remarkable growth in distance learning courses in higher education. Despite indications that distance learning courses are more vulnerable to cheating behavior than traditional courses, there has been little research studying whether online exams facilitate a relatively greater level of cheating. This article examines this issue by developing an approach using a latent variable to measure student cheating. This latent variable is linked to both known student mastery related variables and variables unrelated to student mastery. Grade scores from a proctored final exam and an unproctored final exam are used to test for increased cheating behavior in the unproctored exam

  20. Antioxidant Profile of <em>Trifolium pratenseem> L.

    Directory of Open Access Journals (Sweden)

    Heidy Schwartsova

    2012-09-01

    Full Text Available In order to examine the antioxidant properties of five different extracts of <em>Trifolium pratenseem> L. (Leguminosae leaves, various assays which measure free radical scavenging ability were carried out: 1,1-diphenyl-2-picrylhydrazyl, hydroxyl, superoxide anion and nitric oxide radical scavenger capacity tests and lipid peroxidation assay. In all of the tests, only the H2O and (to some extent the EtOAc extracts showed a potent antioxidant effect compared with BHT and BHA, well-known synthetic antioxidants. In addition, <em>in vivo em>experiments were conducted with antioxidant systems (activities of GSHPx, GSHR, Px, CAT, XOD, GSH content and intensity of LPx in liver homogenate and blood of mice after their treatment with extracts of <em>T. pratenseem> leaves, or in combination with CCl4. Besides, in the extracts examined the total phenolic and flavonoid amounts were also determined, together with presence of the selected flavonoids: quercetin, luteolin, apigenin, naringenin and kaempferol, which were studied using a HPLC-DAD technique. HPLC-DAD analysis showed a noticeable content of natural products according to which the examined <em>Trifolium pratenseem> species could well be regarded as a promising new source of bioactive natural compounds, which can be used both as a food supplement and a remedy.