840 research outputs found

    Estimates for the Poisson kernel and Hardy spaces on compact manifolds

    Get PDF
    AbstractWe study Hardy spaces on the boundary of a smooth open subset or Rn and prove that they can be defined either through the intrinsic maximal function or through Poisson integrals, yielding identical spaces. This extends to any smooth open subset of Rn results already known for the unit ball. As an application, a characterization of the weak boundary values of functions that belong to holomorphic Hardy spaces is given, which implies an F. and M. Riesz type theorem

    Produção De Biomassa E ConteĂșdo De FenĂłis E Flavonoides De Schinus Terebinthifolius Cultivada Em Fileira Simples E Dupla Com Cama De Frango

    Get PDF
    The aim of this study was to evaluate the influence of the addition of poultry litter on growth, biomass yield, flavonoid and phenol content, and antioxidant activity in leaves of pink pepper. The experiment was carried out at the Federal University of Grande Dourados, in Dourados, Mato Grosso do Sul state, from October 2009 to May 2010. Pink pepper was grown in single or double row in soil with incorporated poultry litter at doses of 0, 5, 10, 15 and 20 t ha-1. Treatments were arranged as 2 x 5 factorial in a randomized block design with four replications. There was a significant interaction between the doses of poultry litter and evaluation times for plant height and chlorophyll content. A linear increase in leaf area, fresh and dry weight of leaves and diameter of main stems with increasing doses of poultry litter was observed. Plants grown in single row showed higher fresh weight of stem with increasing doses of poultry litter. Poultry litter at 15 and 20 t ha-1 promoted an increase in flavonoid and phenolic contents in the leaves. No significant effect on the antioxidant activity was observed by the chemical method using DPPH. Therefore, it is recommended the cultivation of pink pepper plants with double row and 20 t ha-1 of poultry litter to higher growth, biomass yield, and flavonoid and phenol content. © 2016, Universidade Federal de Santa Maria. All rights reserved.26378779

    Geometric evaluation of stiffened steel plates subjected to transverse loading for naval and offshore applications

    Get PDF
    This work searched for the optimal geometrical configuration of simply supported stiffened plates subjected to a transverse and uniformly distributed load. From a non-stiffened reference plate, different geometrical configurations of stiffened plates, with the same volume as the reference plate, were defined through the constructal design method. Thus, applying the exhaustive search technique and using the ANSYS software, the mechanical behaviors of all the suggested stiffened plates were compared to each other to find the geometrical configuration that provided the minimum deflection in the plate's center when subjected to this loading. The optimum geometrical configuration of stiffeners is presented at the end of this work, allowing a reduction of 98.57% for the central deflection of the stiffened plate if compared to the reference plate. Furthermore, power equations were adjusted to describe the deflections for each combination of longitudinal and transverse stiffeners as a function of the ratio between the height and the thickness of the stiffeners. Finally, a unique equation for determining the central deflections of the studied stiffened plates based only on the number of longitudinal stiffeners without significantly losing accuracy has been proposed

    More than maternal sensitivity shapes attachment : infant coping and temperament

    Get PDF
    The aim of this longitudinal studywas to investigate the effect of a set of factors from multiple levels of influence: infant temperament, infant regulatory behavior, and maternal sensitivity on infant’s attachment. Our sample consisted of 48 infants born prematurely and their mothers. At 1 and 3 months of age, mothers described their infants’behavior using the Escala de Temperamento do Beb®e. At 3 months of age, infants’ capacity to regulate stress was evaluated during Tronick’s Face-to-Face Still-Face (FFSF) paradigm. At 9 months of age, mothers’ sensitivity was evaluated during free play using the CARE-Index. At 12 months of age, infants’ attachment security was assessed during Ainsworth’s Strange Situation. A total of 16 infants were classified as securely attached, 17 as insecure-avoidant, and 15 as insecure-resistant. Mothers of securely attached infantswere more likely than mothers of insecure infants to describe their infants as less difficult and to be more sensitive to their infants in free play. In turn, secure infants exhibited more positive responses during the Still-Face. Infants classified as insecureavoidant were more likely to self-comfort during the Still-Face and had mothers who were more controlling during free play. Insecure-resistant exhibited higher levels of negative arousal during the Still-Face and had mothers who were more unresponsive in free play. These findings show that attachment quality is influenced bymultiple factors, including infant temperament, coping behavior, and maternal sensitivity

    An emerging class of air pollutants: potential effects of microplastics to respiratory human health?

    Get PDF
    It is increasingly recognized that the ubiquity of convenient single-use plastic has resulted in a global plastic pollution challenge, with substantial environmental and health consequences. Physical, chemical, and biological processes result in plastic weathering, with eventual formation of debris in the micro to nano size range. There is an increasing awareness that plastic fragments are dispersed in the air and can be inhaled by humans, which may cause adverse effects on the respiratory system and on other systems. Urban environments are often characterized by high concentrations of fine airborne dust from various sources. To date, however, there is limited information on the distribution, shape, and size of microplastics in the air in urban and other environments. In this article, we review and discuss our current understanding of the exposure characteristics of airborne plastic debris in urbanized areas, focusing on concentration, size, morphology, presence of additives and distributions of different polymers. The natural and extend data are compiled and compared to laboratory-based analyses to further our understanding of the potential adverse effects of inhaled plastic particles on human health.Environmental Biolog

    Development of poly (lactic-co-glycolic acid)/bioglass fibers using an electrospinning technique.

    Get PDF
    This work establishes experimental conditions for the synthesis of polymeric fibers using the electrospinning technique, modifying some operational parameters such as drum collector rotation speed and applied voltage were modified. The samples were obtained from a copolymer of poly(lactic-co-glycolic acid) (PLGA), with a molecular weight of approximately 220,000 g/mol, dissolved in a dimethyl sulfoxide/dichloromethane (3:1 v/v) solution. With the aim of developing scaffolds for bone tissue engineering, we added a calcium phosphate glass based on 44.5Ca0-44.5P2O5-11Na2O to the fibrous PLGA structures. The preliminary characterization of these PLGA structures with and without the addition of biodegradable glass was performed using SEM analysis. We found the formation of aligned and homogeneous fibers with an average diameter of 5.2 ± 2.1 ”m when using the 800 rpm - 8cm - 9 kV parameters. In addition, the incorporation of 1 wt% of previously silanized calcium phosphate particles substantially altered the fiber morphology and porosity. However, a substantial increase in the bioactivity of the composite was observed in contrast with the unmodified PLGA
    • 

    corecore