47 research outputs found

    Computational Model of the Insect Pheromone Transduction Cascade

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    A biophysical model of receptor potential generation in the male moth olfactory receptor neuron is presented. It takes into account all pre-effector processes—the translocation of pheromone molecules from air to sensillum lymph, their deactivation and interaction with the receptors, and the G-protein and effector enzyme activation—and focuses on the main post-effector processes. These processes involve the production and degradation of second messengers (IP3 and DAG), the opening and closing of a series of ionic channels (IP3-gated Ca2+ channel, DAG-gated cationic channel, Ca2+-gated Cl− channel, and Ca2+- and voltage-gated K+ channel), and Ca2+ extrusion mechanisms. The whole network is regulated by modulators (protein kinase C and Ca2+-calmodulin) that exert feedback inhibition on the effector and channels. The evolution in time of these linked chemical species and currents and the resulting membrane potentials in response to single pulse stimulation of various intensities were simulated. The unknown parameter values were fitted by comparison to the amplitude and temporal characteristics (rising and falling times) of the experimentally measured receptor potential at various pheromone doses. The model obtained captures the main features of the dose–response curves: the wide dynamic range of six decades with the same amplitudes as the experimental data, the short rising time, and the long falling time. It also reproduces the second messenger kinetics. It suggests that the two main types of depolarizing ionic channels play different roles at low and high pheromone concentrations; the DAG-gated cationic channel plays the major role for depolarization at low concentrations, and the Ca2+-gated Cl− channel plays the major role for depolarization at middle and high concentrations. Several testable predictions are proposed, and future developments are discussed

    Avaliação de estratégias para representação e análise do planejamento e controle de obras utilizando modelos BIM 4D

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    ResumoO objetivo deste artigo é avaliar estratégias para representação e análise do planejamento e controle de obras utilizando Modelos BIM 4D, segundo a visão de profissionais da indústria da construção civil brasileira. A pesquisa envolveu revisão bibliográfica sobre o tema, estudo de caso em um empreendimento com utilização do modelo para planejamento e controle da obra e o desenvolvimento e aplicação de questionário digital para avaliação das potencialidades e estratégias pelos profissionais do setor. O questionário da pesquisa abordou estratégias para representação e análise utilizando cores para diferenciação das atividades internas, alternativas de monitoramento do avanço físico através de simulação dos cronogramas Planejado e Realizado, e visualização deles em tela dividida, além de avaliação sobre adoção de modelos 4D. Os resultados obtidos indicam os graus de importância e aplicabilidade dos aspectos analisados na visão geral dos participantes e estratificados por nível de conhecimento sobre BIM, formação profissional, área de atuação e grau acadêmico

    BHPR research: qualitative1. Complex reasoning determines patients' perception of outcome following foot surgery in rheumatoid arhtritis

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    Background: Foot surgery is common in patients with RA but research into surgical outcomes is limited and conceptually flawed as current outcome measures lack face validity: to date no one has asked patients what is important to them. This study aimed to determine which factors are important to patients when evaluating the success of foot surgery in RA Methods: Semi structured interviews of RA patients who had undergone foot surgery were conducted and transcribed verbatim. Thematic analysis of interviews was conducted to explore issues that were important to patients. Results: 11 RA patients (9 ♂, mean age 59, dis dur = 22yrs, mean of 3 yrs post op) with mixed experiences of foot surgery were interviewed. Patients interpreted outcome in respect to a multitude of factors, frequently positive change in one aspect contrasted with negative opinions about another. Overall, four major themes emerged. Function: Functional ability & participation in valued activities were very important to patients. Walking ability was a key concern but patients interpreted levels of activity in light of other aspects of their disease, reflecting on change in functional ability more than overall level. Positive feelings of improved mobility were often moderated by negative self perception ("I mean, I still walk like a waddling duck”). Appearance: Appearance was important to almost all patients but perhaps the most complex theme of all. Physical appearance, foot shape, and footwear were closely interlinked, yet patients saw these as distinct separate concepts. Patients need to legitimize these feelings was clear and they frequently entered into a defensive repertoire ("it's not cosmetic surgery; it's something that's more important than that, you know?”). Clinician opinion: Surgeons' post operative evaluation of the procedure was very influential. The impact of this appraisal continued to affect patients' lasting impression irrespective of how the outcome compared to their initial goals ("when he'd done it ... he said that hasn't worked as good as he'd wanted to ... but the pain has gone”). Pain: Whilst pain was important to almost all patients, it appeared to be less important than the other themes. Pain was predominately raised when it influenced other themes, such as function; many still felt the need to legitimize their foot pain in order for health professionals to take it seriously ("in the end I went to my GP because it had happened a few times and I went to an orthopaedic surgeon who was quite dismissive of it, it was like what are you complaining about”). Conclusions: Patients interpret the outcome of foot surgery using a multitude of interrelated factors, particularly functional ability, appearance and surgeons' appraisal of the procedure. While pain was often noted, this appeared less important than other factors in the overall outcome of the surgery. Future research into foot surgery should incorporate the complexity of how patients determine their outcome Disclosure statement: All authors have declared no conflicts of interes

    Characterization of Speed And Direction Wind Predominant in the Region of Sinop, Mato Grosso

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    <p><strong>Abstract: </strong><em>Evaluated the evolution of monthly average hourly values and frequencies of occurrence of wind speed and direction (VV and DV) in the region of Sinop, Mato Grosso. The meteorological data were collected by the automatic station A917 INMET (1158'56" S and 55 33'57" W) in the period from 01/2007 to 12/2010. The highest average wind speed occur at moments of net radiation, predominantly gusts mainly in winter. The predominant directions are north and northeast for spring and summer and Northeast and Southeast for fall and winter.</em></p><strong><em>Keywords</em></strong><em>: frequency of occurrence, diurnal evolution, gusty winds</em

    Climatic Water Balance and Classification of Climate of the Region Sinop, Mato Grosso State, Brazil

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    Abstract: Evaluated the climatic characterization of region of Sinop-MT, through the database of daily of the conventional meteorological station "Gleba Celeste" (12 12'S and 56 30'W, at an altitude of 415m), the period 07/1972 to 07/2010. Climatic water balance by region shows annual rainfall of 1974.47 mm and annual reference evapotranspiration (ETo) obtained by the method of Thornthwaite equal to 1327.29 mm, with oscillations of deficiencies and excess water dependent water holding capacity of the soil. The region presents the types and climatic Aw and B2wA'a' for Kpens and Thornthwaites climatic classification method, with well-defined seasons: rainy (October to April) and dry (May to September). Keywords: time series climatic, air temperature, evapotranspiration</p
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