378 research outputs found

    Fungicide And Drying Effects On The Viability Of Recalcitrant Seeds Of Inga Vera Subsp. Affinis

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    Studies on the health and quality of seeds from native tree species are scarce in the tropics, which is the case of Inga vera, a recalcitrant-seeded Brazilian species used in reforestation. In this study a series of experiments were conducted to analyze the effects of fungicides and hydration levels on the suppression of seed borne fungi and seed physiology. Firstly, three commercially available fungicide formulations (thiram, carbendazim + thiram and carboxin + thiram) for seed treatment were evaluated. Secondly, embryos were subjected to a combination of four drying levels (62, 52, 44 e 34 % water content) with or without fungicide (carbendazim + thiram). All three preliminary screened fungicide formulations were not phytotoxic, with carbendazim + thiram performing best. Seed deterioration was associated with a high incidence of fungi at any level of drying. Fungicide treatment reduced the incidence of the most common fungi (Acremonium curvulum and Phomopsis diachenii) and extended the lifespan of non-dried embryos from 90 to 120 days. © 2016, Sociedade Brasileira de Fitopatologia.41317718

    Microsatellite variation in Spanish Alano dogs

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    We have studied a sample of 35 spanish alano dogs in order to estimate the level of genetic variability that can be detected by using microsatellites and the efficiency of these genetic markers as tools for parentage testing in this canine population. We have used 4 microsatellites previously described in the literature. All of them were polymorphic, with an average number of 5 alleles/ locus and an average gene diversity (H) of 0,70 ± 0,06, similar to the figures reported in others breeds. Two of the microsatellites showed disa-greement with Hardy-Weinberg proportions, due to a deficit of heterozygotes. We have found in one of the microsatellites alleles that could be breed specific, as they have not been detected in other spanish breeds. The combined exclusion probability detected is higher than 90 percent, suggesting the possibility of using efficiently microsatellites in parentage testing in the spanish alano population.En una muestra de 35 alanos españoles se investigó la utilidad de los microsatélites para detectar variabilidad genética y para el control de paternidad. Los 4 microsatélites utilizados, descritos ya en la bibliografía, resultaron polimórficos, con un número medio de 5 alelos/ locus y una heterocigosis media (H), de 0,70 ± 0,06, similar a la de otras razas caninas. Se ha detectado una desviación del equilibrio Hardy-Weinberg para dos microsatélites debida a un déficit de heterocigotos. En un microsatélite se han detectado alelos inexistentes en otras razas españolas, por lo que podrían ser específicos de raza. La probabilidad acumulada de exclusión de paternidad es superior al 90 p.100, por lo que podrían ser eficaces para estas pruebas en alanos

    A Pinned Polymer Model of Posture Control

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    A phenomenological model of human posture control is posited. The dynamics are modelled as an elastically pinned polymer under the influence of noise. The model accurately reproduces the two-point correlation functions of experimental posture data and makes predictions for the response function of the postural control system. The physiological and clinical significance of the model is discussed.Comment: uuencoded post script file, 17 pages with 3 figure

    Genetic Evidence for a Causal Role of Serum Phosphate in Coronary Artery Calcification:The Rotterdam Study

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    BACKGROUND: Hyperphosphatemia has been associated with coronary artery calcification (CAC) mostly in chronic kidney dis-ease, but the association between phosphate levels within the normal phosphate range and CAC is unclear. Our objectives were to evaluate associations between phosphate levels and CAC among men and women from the general population and assess causality through Mendelian randomization. METHODS AND RESULTS: CAC, measured by electron-beam computed tomography, and serum phosphate levels were assessed in 1889 individuals from the RS (Rotterdam Study). Phenotypic associations were tested through linear models adjusted for age, body mass index, blood pressure, smoking, prevalent cardiovascular disease and diabetes, 25-hydroxyvitamin D, total calcium, C-reactive protein, glucose, and total cholesterol: high-density lipoprotein cholesterol ratio. Mendelian randomiza-tion was implemented through an allele score including 8 phosphate-related single-nucleotide polymorphisms. In phenotypic analyses, serum phosphate (per 1 SD) was associated with CAC with evidence for sex interaction (Pinteraction =0.003) (men β, 0.44 [95% CI, 0.30– 0.59]; P=3×10−9; n=878; women β, 0.24 [95% CI, 0.08– 0.40]; P=0.003; n=1011). Exclusion of hyperphos-phatemia, chronic kidney disease (estimated glomerular filtration rate &lt;60 mL/min per 1.73 m2) and prevalent cardiovascular disease yielded similar results. In Mendelian randomization analyses, instrumented phosphate was associated with CAC (total population β, 0.93 [95% CI: 0.07–1.79]; P=0.034; n=1693), even after exclusion of hyperphosphatemia, chronic kidney disease and prevalent cardiovascular disease (total population β, 1.23 [95% CI, 0.17– 2.28]; P=0.023; n=1224). CONCLUSIONS: Serum phosphate was associated with CAC in the general population with stronger effects in men. Mendelian randomization findings support a causal relation, also for serum phosphate and CAC in subjects without hyperphosphatemia, chronic kidney disease, and cardiovascular disease. Further research into underlying mechanisms of this association and sex differences is needed.</p

    ADAMTS -1 and -4 are up-regulated following transient middle cerebral artery occlusion in the rat and their expression is modulated by TNF in cultured astrocytes

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    ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) enzymes are a recently described group of metalloproteinases. The substrates degraded by ADAMTS-1, -4 and -5 suggests that they play a role in turnover of extracellular matrix in the central nervous system (CNS). ADAMTS-1 is also known to exhibit anti-angiogenic activity. Their main endogenous inhibitor is tissue inhibitor of metalloproteinases (TIMP)-3. The present study was designed to investigate ADAMTS-1, -4 and -5 and TIMP-3 expression after experimental cerebral ischaemia and to examine whether cytokines known to be up-regulated in stroke could alter their expression by astrocytes in vitro. Focal cerebral ischaemia was induced by transient middle cerebral artery occlusion in the rat using the filament method. Our results demonstrate a significant increase in expression of ADAMTS-1 and -4 in the occluded hemisphere but no significant change in TIMP-3. This was accompanied by an increase in mRNA levels for interleukin (IL)-1, IL-1 receptor antagonist (IL-1ra) and tumour necrosis factor (TNF). ADAMTS-4 mRNA and protein was up-regulated by TNF in primary human astrocyte cultures. The increased ADAMTS-1 and -4 in experimental stroke, together with no change in TIMP-3, may promote ECM breakdown after stroke, enabling infiltration of inflammatory cells and contribute to brain injury. In vitro studies suggest that the in vivo modulation of ADAMTS-1 and -4 may be controlled in part by TNF.</p

    Active flux seasonality of the small dominant migratory crustaceans and mesopelagic fishes in the Gulf of California during June and October

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    The biological carbon pump is the process that transports carbon vertically out of the mixed layer in the ocean. Besides the sinking flux of organic particles, active flux due to the daily vertical migration of zooplankton and micronekton promotes a significant carbon transport not fully accounted for or understood in the world’s oceans. The diversity and abundance of epipelagic and mesopelagic species in the Gulf of California has been extensively studied, but the role of micronekton in carbon export has not yet been investigated. We studied the carbon flux promoted by juvenile and adult mesopelagic fishes and crustaceans (Decapoda and Euphausiidae) during the transition from the cold to warm period (June) and the onset of the warm season (October) in 2018. We provide the first estimation of migrant biomass and respiratory flux of the most abundant migratory species of mesopelagic fishes, decapods and euphausiids in the Gulf of California. The micronekton species collected accounted for a large biomass of mesopelagic fishes and pelagic crustaceans. The average migrant biomass estimates were 151.5 ± 101.2 mg C·m−2 during June and 90.9 ± 75.3 mg C·m−2 during October. The enzymatic activity of the electron transfer system (ETS) was measured as an estimate of their respiratory rates. Average specific ETS activity was significantly different between fishes and decapods, and between fishes and euphausiids (p < 0.05). The respiratory flux of fishes was predominant in the Gulf of California, followed by pelagic decapods and euphausiids. Seasonal changes in respiratory flux were observed for fishes (June: 6.1 ± 1.5 mg C·m−2·d−1; October: 3.2 ± 1.8 mg C·m−2·d−1) and decapods (June: 0.4 mg C·m−2·d−1; October: 0.7 ± 0.05 mg C·m−2·d−1). Respiratory flux estimation by crustaceans (decapods and euphausiids) and fishes together was 6.86 mg C·m−2·d−1 during June, and 4.21 mg C·m−2·d−1 during October 2018, suggesting a functional role of this large micronektonic fauna in the biological carbon export in this region.3,26

    Recent results on multiplicative noise

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    Recent developments in the analysis of Langevin equations with multiplicative noise (MN) are reported. In particular, we: (i) present numerical simulations in three dimensions showing that the MN equation exhibits, like the Kardar-Parisi-Zhang (KPZ) equation both a weak coupling fixed point and a strong coupling phase, supporting the proposed relation between MN and KPZ; (ii) present dimensional, and mean field analysis of the MN equation to compute critical exponents; (iii) show that the phenomenon of the noise induced ordering transition associated with the MN equation appears only in the Stratonovich representation and not in the Ito one, and (iv) report the presence of a new first-order like phase transition at zero spatial coupling, supporting the fact that this is the minimum model for noise induced ordering transitions.Comment: Some improvements respect to the first versio
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