1,491 research outputs found

    Endogenous Timing in Duopoly: Experimental Evidence

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    In this paper we experimentally investigate the extended game with observable delay of Hamilton and Slutsky (Games Econ.Beh., 1990).Firms bindingly announce a production period (one out of two periods) and then they produce in the announced sequence.Theory predicts simultaneous production in period one but we find that a substantial proportion of subjects choose the second period.Commitment;Endogenous timing;Experimental economics;Cournot;Stackel- berg

    Giant FAZ10 is required for flagellum attachment zone stabilization and furrow positioning in Trypanosoma brucei

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    The flagellum and flagellum attachment zone (FAZ) are important cytoskeletal structures in trypanosomatids, being required for motility, cell division and cell morphogenesis. Trypanosomatid cytoskeletons contain abundant high molecular mass proteins (HMMPs), but many of their biological functions are still unclear. Here, we report the characterization of the giant FAZ protein, FAZ10, in Trypanosoma brucei, which, using immunoelectron microscopy, we show localizes to the intermembrane staples in the FAZ intracellular domain. Our data show that FAZ10 is a giant cytoskeletal protein essential for normal growth and morphology in both procyclic and bloodstream parasite life cycle stages, with its depletion leading to defects in cell morphogenesis, flagellum attachment, and kinetoplast and nucleus positioning. We show that the flagellum attachment defects are probably brought about by reduced tethering of the proximal domain of the paraflagellar rod to the FAZ filament. Further, FAZ10 depletion also reduces abundance of FAZ flagellum domain protein, ClpGM6. Moreover, ablation of FAZ10 impaired the timing and placement of the cleavage furrow during cytokinesis, resulting in premature or asymmetrical cell division

    Influence of sampling date on soil nitrogen availability indices

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    In spite of the great effort that has been devoted to the search for a chemical laboratory index to predict nitrogen (N) mineralization capability of soils, the results have not yet been fully satisfactory. A continued effort is still needed to increase the knowledge of the sources of variation that influence potentially available soil N. The time of sampling has received little attention, taking into account its potential to influence N-mineralization patterns. In this work, soil samples from three different agrosystems, consisting of a double-crop sequence of small grains and maize, an intensively grazed pasture, and a rainfed olive orchard, were collected at different dates. Several chemical extractions were performed, and the results were correlated with N uptake by turnip (Brassica campestris, L.) grown in a pot experiment. Kjeldahl N was the chemical test that best correlated (R2 = 0.621) with N uptake by turnip. Kjeldahl N showed great versatility relative to the origin of the soil samples. However, it was not very sensitive to the time of sampling. It did not detect changes occurring in the soil over a short period of time. Soil inorganic N showed the second highest coefficient of correlation (R2 = 0.483) with N uptake by turnip. In contrast to that observed with Kjeldahl N, soil inorganic N appeared as an index that can vary greatly over the short term. The hot saline potassium chloride (KCl) extractions gave generally fair results. The poorest, however, were obtained with the ultraviolet absorption of extracts of 0.01 mol L−1 sodium bicarbonate (NaHCO3) measured at 250- and 260-nm wavelengths

    Effect of sampling date on chemical indices of the mineralizable nitrogen in soil

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    In the 1960s and 1970s there was great emphasis on selecting simple laboratory methods to estimate the potentially available soil N that could be routinely used as a method for the N recommendations systems (Keeney and Breniner, 1966; Stanford and Smith, 1976). Many chemical extractants were investigated (acids alkali, salts, water…) as possible tools for assessing how much N may be mineralized, varying the concentration of the extractant, temperature and time of extractions

    Controle da produção de aflatoxinas no amendoim em casca úmido com ortofenilfenato de sódio: III. Testes no armazém

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    The present experiment aimed to evaluate the effect of sodium ortho-phenylphenate (SOP) application to in-shell moist peanuts for the control of aflatoxin production. Previous studies showed the need to improve the SOP solution distribution on peanut pods to evaluate the product. Thus, in this experiment the place of the spray system was the bag filler pipe of the pre-cleaning machine in the warehouse. In the 1989 rainy season two lots of 120 bags of in-shell moist peanuts were sprayed with 0.5 and 1% SOP solutions and aflatoxin production was not controlled. In the dry season of 1989 and in the rainy season of 1990, in-shell moist peanuts were sprayed with 5% SOP solution. The coverage of pods with the solution was efficient, allowing a uniform distribution of SOP solution on the pods. The results showed that only the 5.0% concentration of SOP solution utilized controlled the external fungal growth when a naked eye observation was made, however did not control aflatoxin production when applied to in-shell moist peanuts, probably due to the internal presence of Aspergillus flavus and because the fungicide could not penetrate inside to reach the kernels.O presente trabalho teve por objetivo avaliar a eficiência da solução de ortofenilfenato de sódio (OFS), no controle da produção de aflatoxinas quando aplicada no amendoim em casca, úmido. Trabalhos anteriormente realizados, em condições de campo, indicaram a necessidade de otimizar a aplicação da solução, para se poder avaliar a real eficiência dessa substância. Assim, neste experimento, o sistema de pulverização foi adaptado na bica de saída da máquina de pré-limpeza, no armazém. Na safra das águas de 1989, dois lotes de 120 sacos de amendoim em casca úmido foram pulverizados com solução de OFS em concentrações de 0,5 e 1,0 % e verificou-se que não houve controle da produção de aflatoxinas em ambas as concentrações utilizadas. Nas safras da seca de 1989 e das águas de 1990 o amendoim em casca úmido foi pulverizado com solução de OFS na concentração de 5,0%. A cobertura das vagens com a solução foi eficiente, permitindo uma distribuição uniforme da solução de OFS sobre as vagens. Os resultados obtidos mostraram que nenhuma das concentrações utilizadas controlou a produção de aflatoxinas, quando aplicadas no amendoim em casca, embora, aparentemente, tenham controlado o crescimento fúngico da parte externa das vagens de amendoim. Provavelmente os fungos aflatoxigênicos já poderiam estar presentes dentro de vagens sadias e desse modo a casca do amendoim poderia ser uma barreira à penetração do fungicida dentro da vagem e atingir as amêndoas

    Hypertrophic reversed palmaris longus muscle: a cadaveric finding

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    Variations of the forearm musculature are vastly described in the literature. The palmaris longus muscle is one of the most variable structures of the human body. It usually arises from the medial epicondyle of the humerus and inserts itself into the palmar aponeurosis. Anatomy textbooks and recent papers state that this muscle may act as a weak wrist flexor. The present work aims to report an anatomical variation where the palmaris longus muscle was abnormally hypertrophied and was completely fleshy throughout the whole forearm. Anatomical variations of the palmaris longus may induce symptoms of neurovascular bundle compression, especially of the median nerve. The palmaris longus muscle may be used in tendon graft or muscle graft, due to its lack of apparent function. Furthermore, it is one of the anatomical landmarks for local anaesthesia procedures. (Folia Morphol 2018; 77, 2: 403–405
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