2,018 research outputs found

    Estimates for the Poisson kernel and Hardy spaces on compact manifolds

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    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

    Selective pressure acting on influenza virus neuraminidase protein and relation with development of resistance to antiviral drugs

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    Neuraminidase (NA) protein of influenza viruses has the particularity of being under antibody and antiviral drug selective pressure, as it is one of the main surface antigens and the target of neuraminidase inhibitors(NAIs). The aim of this study is to investigate the selective pressure(SP) acting on the NA of seasonal and pandemic influenza viruses. It comprises two objectives: (a)to evaluate the contribution of positive SP for the emergence of NAIs resistant viruses; and (b)to determine the impact of NAIs introduction into clinic and its wide use during pandemic on the SP acting on NA. For the 1st objective it will be analysed the SP acting on the sites associated with NAIs resistance or reduction in susceptibility. The 2nd objective implies a differential evolutionary pressure analysis according to time, with 3 sub-datasets of NA sequences being considered: (1)before worldwide introduction of NAIs into clinic(1999); (2)before wide use of oseltamivir during A(H1N1)2009 pandemic(2009); and (3)from 2009 to date. A large dataset of full-length NA coding sequences will be used for each (sub)type/variant, comprising sequences obtained at national level(since 2000/2001) and sequences available at GISAID and NCBI. A(H1N1)seasonal dataset was already created, including a total of 1523 sequences, from which 94 belong to 1st sub-dataset, 1094 to 2nd and 335 to 3rd. All SP analysis will be performed using the expertise acquired with this workshop. This study may contribute for understanding the role of antiviral drug selective pressure in NAIs resistance, patterns of emergency of resistant viruses and NA evoluti

    Produção De Biomassa E Conteúdo De Fenóis E Flavonoides De Schinus Terebinthifolius Cultivada Em Fileira Simples E Dupla Com Cama De Frango

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    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

    Evaluation and Characterization of Influenza Antiviral Drug Resistance in Portugal: Major Results and Achievements of a 5-Year Study

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    In 2007 started to be carried out for the first time in Portugal a study focused on influenza antiviral drug resistance. Three main objectives were established:(1)to determine the antiviral profile of influenza viruses to oseltamivir, zanamivir and amantadine;(2)to determine and monitor the baseline level of susceptibility along winter seasons and for each influenza sub(type);(3)to analyse and characterize the whole genome of viruses that showed phenotypic levels of inhibition to neuraminidase inhibitors(NAIs). NAIs profile was determined phenotypically, using a fluorescence MUNUNA assay, and genotypically by NA and HA sequencing. A total of 340 seasonal viruses(117 A(H3N2),93 A(H1N1),130 B) were tested for oseltamivir and of 297(112 A(H3N2),68 A(H1N1),117 B) for zanamivir. Additionally, 142 A(H1N1)pdm09 viruses were evaluated for both NAIs. Whole genome sequencing was performed in 27 of the A(H1N1)pdm09 viruses. Amantadine profile was determined through M2 pyrosequencing or conventional sequencing in a total of 205 seasonal A viruses(138 A(H3N2),84 A(H1N1)) and of 117 A(H1N1)pdm09 viruses. Main results are: -Resistance to oseltamivir in 27 A(H1N1) seasonal viruses(29%,N=93) from 2007/2008 and 2008/2009 and in one A(H1N1)pdm09 virus(0.7%,N=142) from 2010/2011. These viruses exhibited a highly reduced level of inhibition to oseltamivir by phenotypic analysis (170-650 IC50 fold-change) and NA H275Y mutation; -One suspected case of clinical resistance to oseltamivir with a mixed population of H275Y viruses(73,8%H275,26.2%Y275); -No resistance to zanamivir; -Dual reduced susceptibility to oseltamivir and zanamivir in one B virus(0,85%,N=117) and in two A(H1N1)pdm09 viruses(1,41%,N=142). These viruses exhibited a 2-4 IC50 fold-change level of inhibition to both NAIs. A mixed population of D197N viruses was found in the B virus(56%D197,44%N197) and the two A(H1N1)pdm09 viruses shared NA I223V and PB2 V480I mutations; -Resistance to amantadine in 49 A(H3N2) viruses(35,5%,N=138) from 2005/2006 to 2008/2009(46 S31N,3 S31N+V27A), and in all A(H1N1)pdm09 viruses(S31N). This 5-year study allowed to establish a technical platform for influenza antiviral drug resistance evaluation, to timely detect the emergence of resistant viruses, to acquire know-how on the natural variation of virus susceptibility, and to contribute for the management of cases suspected of clinical resistance. Additionally, it allowed the gathering of a large amount of data that will be used in more advanced studies, focused on evolutionary analysis and on detailed characterization of specific mutations

    Quantum nanofriction in trapped ion chains with a topological defect

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    Trapped ion systems constitute a well controllable scenario for the study and emulation of nanofriction, and in particular of Frenkel-Kontorova-like models. This is in particular the case when a topological defect is created in a zigzag ion Coulomb crystal, which results in an Aubry transition from free sliding to pinned phase as a function of the trap aspect ratio. We explore the quantum effects of the Aubry transition by means of an effective simplified model, in which the defect is treated like a single quantum particle that experiences an effective Peierls-Nabarro potential and a position-dependent mass. We demonstrate the relevance of quantum tunneling in a finite range of aspect ratios close the critical point, showing that the quantum effects may be observed in the kink dynamics for sufficiently low temperatures. Finally, we discuss the requirements to reveal quantum effects at the Aubry transition in future experiments on trapped ions

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

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    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

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    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

    Newborn and childhood differential DNA methylation and liver fat in school-age children

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    Background: Non-alcoholic fatty liver disease is the most common chronic liver disease in children in western countries. Adverse early-life exposures are associated with higher liver fat percentages in children. Differential DNA methylation may underlie these associations. We aimed to identify differential DNA methylation in newborns and children associated with liver fat accumulation in childhood. We also examined whether DNA methylation at 22 cytosine-phosphate-guanine sites (CpGs) associated with adult non-alcoholic fatty liver disease is associated with liver fat in children. Within a population-based prospective cohort study, we analyzed epigenome-wide DNA methylation data of 785 newborns and 344 10-year-old children in relation to liver fat fraction at 10 years. DNA methylation was measured using the Infinium HumanMethylation450 BeadChip (Illumina). We measured liver fat fraction by Magnetic Resonance Imaging. Associations of single CpG DNA methylation at the two-time points with liver fat accumulation were analyzed using robust linear regression models. We also analyzed differentially methylation regions using the dmrff package. We looked-up associations of 22 known adult CpGs at both ages with liver fat at 10 years. Results: The median liver fat fraction was 2.0% (95% range 1.3, 5.1). No single CpGs and no differentially methylated regions were associated with liver fat accumulation. None of the 22 known adult CpGs were associated with liver fat in children. Conclusions: DNA methylation at birth and in childhood was not associated with liver fat accumulation in 10-year-old children in this study. This may be due to modest sample sizes or DNA methylation changes being a consequence rather than a determinant of liver fat

    Prostephanus truncatus IN AFRICA: A REVIEW OF BIOLOGICAL TRENDS AND PERSPECTIVES ON FUTURE PEST MANAGEMENT STRATEGIES

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    The pest status of the Larger grain borer, Prostephanus truncatus (Coleoptera: Bostrichidae), is higher in African countries than in Latin America, its region of origin. This pest reduces the storage period of maize grain and cassava chips in granaries of small scale farmers. This reduced storage period results from larval and adult feeding, with consequent shortening of the period these commodities are available for food and income generating sources. Depending on storage time, yield losses of up to 45 and 100% have been recorded for maize and cassava chips, respectively, in West Africa; while 62% yield losses have been reported in Mozambique. Since P. truncatus invaded Africa from approximately 1970, research mostly addressed its biology, ecology, dispersal and control methods. This review paper aims at evaluating P. truncatus pest status in Africa as a basis for designing pragmatic strategies for its control. Prostephanus truncatus pest status in Africa is high and the degree of infestation and damage vary between regions. The variation in pest status is due to climatic conditions, food sources, and degree of storage infra-structure development and efficacy of control methods. Prostephanus truncatus has established in 20 African countries. Its temporal and spatial dispersion is unpredictable and depends on ecological factors, maize and dry cassava trade routes, and availability of forest host plants. Development of sustainable integrated management strategies is a key to future successful management of this pest. Area-wide management strategies using the predator, Teretrius nigrescens , parasitoids, plant derived products and environmentally friendly insecticides is needed. Integrated management practices must be based on improved knowledge of P. truncatus population dynamics and its determining factors.Le statut de la peste de d\ue9voreur des grains, Prostephanus truncatus (Coleoptera: Bostrichidae), est plus \ue9lev\ue9 dans les pays africains que dans ceux d\u2019Am\ue9rique Latine, sa r\ue9gion d\u2019origine. Cette peste r\ue9duit la p\ue9riode de stockage des grains de ma\uefs et de manioc dans des grainiers des petits exploitants. Ceci est d\ufb \ue0 l\u2019alimentation des larves et adultes, avec pour cons\ue9quence, l\u2019\ue9courtement de la p\ue9riode dont de ces produits devraient \ueatre disponibles pour nourriture et sources de g\ue9n\ue9ration des revenues. D\ue9pendamment du temps de stockage, les pertes de rendement d\u2019environ 45 et 100% ont \ue9t\ue9 observ\ue9es pour le ma\uefs et le manioc, respectivement en Afrique de l\u2019ouest; pendant que 62% de pertes de rendement ont \ue9t\ue9 report\ue9es au Mozambique. Depuis l\u2019invasion de l\u2019Afrique par P. truncatus aux environ de 1970, la recherche s\u2019est en grande partie attabl\ue9e sur sa biologie, \ue9cologie, propagation et m\ue9thodes de contr\uf4le. Cette revue \ue9value le statut de la peste P. truncatus en Afrique pour comme base de conception des strat\ue9gies pragmatiques pour son contr\uf4le. Le statut de la peste de Prostephanus truncatus est \ue9lev\ue9 en Afrique et les degr\ue9s d\u2019infestation et dommage varient entre les r\ue9gions. La variation du statut de cette peste est due aux conditions climatiques, sources d\u2019aliments et, degr\ue9 de d\ue9veloppement des infrastructures de stockage et l\u2019efficacit\ue9 des m\ue9thodes de contr\uf4le. Le Prostephanus truncatus s\u2019est \ue9tabli dans 20 pays africains. Sa propagation temporelle et spatiale est impr\ue9dictible et d\ue9pend des facteurs \ue9cologiques, les voies de commercialisation du ma\uefs et manioc sec, et disponibilit\ue9 des plantes h\uf4tes dans des forets. Le d\ue9veloppement durable des strat\ue9gies de gestion int\ue9gr\ue9e est une cl\ue9 pour un succ\ue8s futur de gestion de cette peste. Des strat\ue9gies de gestion utilisant le pr\ue9dateur, Teretrius nigrescens , les parasito\uefdes, les produits d\ue9riv\ue9s des plantes et des insecticides environnementalement viables sont n\ue9cessaires. Des pratiques de gestion int\ue9gr\ue9e doivent \ueatre bas\ue9es sur l\u2019am\ue9lioration des connaissances sur la dynamique des populations de P. truncatus et ses facteurs d\ue9terminants
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