2,005 research outputs found

    Preparation of aromatic geraniol analogues via a Cu(I)-mediated Grignard coupling

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    Difunctional allylic terpenes are important synthetic building blocks. Functionalization of protected geranyl derivatives by SeO2/t-BuO2H adsorbed on SiO2 provides a convenient route to such compounds. The chosen protecting groups clearly influence the oxidation process. Also, an efficient synthesis of 2-geranylphenol derivatives via a Cu(I)-mediated Grignard coupling of 2-lithiophenols and geranyl substrates was developed.Terpenos alílicos difuncionais constituem-se em importantes blocos de construção sintéticos. A funcionalização de derivados geranílicos protegidos por SeO2/t-BuO2H adsorvido em SiO2, propicia uma rota conveniente para tais compostos. Os grupos protetores escolhidos efetivamente influenciam o processo de oxidação. Também, desenvolveu-se uma eficiente síntese de derivados 2-geranilfenóis através de um acoplamento de Grignard mediado por Cu(I) entre derivados de 2-lítiofenóis e substratos geranílicos.975981Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

    Adaptive gossip-based broadcast

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    This paper presents a novel adaptation mechanism that allows every node of a gossip-based broadcast algorithm to adjust the rate of message emission 1) to the amount of resources available to the nodes within the same broadcast group and 2) to the global level of congestion in the system. The adaptation mechanism can be applied to all gossip-based broadcast algorithms we know of and makes their use more realistic in practical situations where nodes have limited resources whose quantity changes dynamically with time without decreasing the reliability.(undefined

    Evaluación de la ejecución motora en niños brasileños en edad escolar

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    Se ha evaluado mediante la batería de Tests Motores de Lincoln-Oseretsky la ejecución motora en un grupo de 1.232 estudiantes de edades comprendidas entre 5 y 16 años provenientes del sistema de enseñanza del municipio de Aracajú (Brasil). Los resultados obtenidos ponen de manifiesto una progresión en el desarrollo de las capacidades motoras, aunque con diferencias de género debidas tanto a factores biológicos como de carácter ambiental. Por otra parte, la edad motora resulta significativamente inferior a la edad cronológica en todas las franjas de edad estudiadas, siendo también inferior a la edad motora de una muestra equivalente de escolares europeos. Este hecho podría atribuirse, al menos parcialmente, a la ausencia de experiencias motoras suficientemente enriquecedoras tanto en el ambiente familiar como en el entorno escolar

    non-linear relationships in children 6-10 years

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    Background: Given the concern for health?related consequences of an elevated body mass index (BMI; obesity), the potential consequences of a low BMI in children are often overlooked. The purpose was to evaluate the relationship between the BMI across its entire spectrum and motor coordination (MC) in children 6?10 years. Methods: Height, weight, and MC (K?rperkoordinationstest f?r Kinder, KTK test battery) were measured in 1,912 boys and 1,826 girls of 6?10 years of age. BMI (kg/m2) was calculated. KTK scores for each of the four tests were also converted to a motor quotient (MQ). One?way ANOVA was used to test differences in the BMI, individual test items, and MQ among boys and girls within age groups. Sex?specific quadratic regressions of individual KTK items and the MQ on the BMI were calculated. Girls and boys were also classified into four weight status groups using International Obesity Task Force criteria: thin, normal, overweight, and obese. Differences in specific test items and MQ between weight status groups were evaluated by age group in each sex. Results: Thirty?one percent of the sample was overweight or obese, whereas 5% was thin. On average, normal weight children had the highest MQ in both sexes across the age range with few exceptions. Overweight/obese children had a lower MQ than normal weight and thin children. The quadratic regression lines generally presented an inverted parabolic relationship between the BMI and MC and suggested a decrease in MC with an increase in the BMI. Conclusion: In general, BMI shows a curvilinear, inverted parabolic relationship with MC in children 6?10 years.4811-99FE-2ECD | Luis Paulo Rodriguesinfo:eu-repo/semantics/publishedVersio

    Siblings’ influence on the motor competence of preschoolers

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    The number of single-child families has been rising steadily in recent years, resulting in a childhood absent of sibling relationships. Being an only child has been shown to have a negative impact on physical fitness, somatic fitness, and motor development. In this study, we aimed to understand how living with and without siblings can impact the motor competence of children. One hundred and sixty-one children (87 boys, 74 girls) from 3.0 to 6.0 years of age (34 only children, 125 siblings) and with no known motor or cognitive disability were assessed using the Motor Competence Assessment (MCA). Their standardized results on the three MCA subscales (stability, locomotor, and manipulative) and total MCA were used to group them into high, average, and low motor competence groups. Motor competence percentile distribution of the sibling and only child group condition was compared using chi-square tests. Results showed a significative and positive association between the sibling condition and the distribution between the three MC groups (chi-square = 6.29; p = 0.043), showing that children in a household with siblings, independent of their age and sex, show a clear tendency for developing better motor competence.L.P.R. and V.P.L. were partly supported by the Portuguese Science Foundation (FCT), under Grant UID04045/2020. R.C. was partly supported by the Portuguese Science Foundation (FCT), under Grant UIDB/00447/2020 (unit 447). The research project was funded by the European Regional Development Fund (ERDF) through the Regional Operational Program North 2020, within the scope of Project TECH-Technology, Environment, Creativity and Health, Norte-01-0145-FEDER-000043.info:eu-repo/semantics/publishedVersio

    E-maturity (e-M): construção e elaboração do questionário de autoavaliação da Gestão Tecnopedagógica

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    O objetivo desse estudo é descrever a proposta de desenvolvimento da ferramenta de avaliação e acompanhamento da gestão tecnopedagógica (e-Maturity). O modelo sistematiza um instrumental de análise do nível de maturidade, em relação ao uso estratégico e eficaz das TIC na melhoria dos resultados educacionais. Nesse sentido, o instrumental colabora na identificação dos usos e apropriações das TIC nas escolas, numa perspectiva da prática pedagógica. O instrumental foi elaborado com base nas ferramentas E-learning Maturity Model - eMM (Marshall e Mitchell, 2004), Self Review Framework for ICT, originalmente desenvolvida na Inglaterra pela Naace - Advancing Education Through ICT e no modelo CM360 proposto por Franco et al (2009), que é um framework de análise e avaliação de maturidade da gestão de conteúdo de uma organização

    E-Maturity: entrelaçando gestão, tecnologia e pedagogia

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    Este artigo apresenta uma abordagem teórica que busca compreender e conceituar o termo e-maturity (maturidade eletrônica), cujo estudo se justifica por ser foco da pesquisa de doutorado intitulada Ematurity: gestão da tecnologia em função da melhoria do desempenho educacional, desenvolvida no Programa de Pós-Graduação em Informática na Educação (PPGIE), da Universidade Federal do Rio Grande do Sul. Para fundamentar o termo (e-maturity) utilizado na pesquisa, retomamos a Teoria da Maturidade-imaturidade, de Chris Argyris (1969), e, buscamos naEngenharia de Software, o Modelo de Maturidade de Capacidade deSoftware- CMM

    Square planar Au(III), Pt(II) and Cu(II) complexes with quinoline-substituted 2,2′:6′,2″-terpyridine ligands: From in vitro to in vivo biological properties

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    This work was supported by the Applied Molecular Biosciences Unit - UCIBIO which is financed by national funds from FCT (UIDP/04378/2020, UIDB/04378/2020 and fellowships SFRH/BPD/124612/2016 (C. Roma-Rodrigues), and PTDC/CVT-EPI/6685/2014 (L R. Raposo)).Cancer is the second leading cause of death worldwide. Cisplatin has challenged cancer treatment; however, resistance and side effects hamper its use. New agents displaying improved activity and more reduced side effects relative to cisplatin are needed. In this work we present the synthesis, characterization and biological activities of three complexes with quinoline-substituted 2,2′:6′,2″-terpyridine ligand: [Pt(4′-(2-quin)-terpy)Cl](SO3CF3) (1), [Au(4′-(2-quin)-terpy)Cl](PF6)2·CH3CN (2) and [Cu(4′-(2-quin)-terpy)Cl](PF6) (3). The three complexes displayed a high antiproliferative activity in ovarian carcinoma cell line (A2780) and even more noticeable in a colorectal carcinoma cell line (HCT116) following the order 3 > 2 > 1. The complexes IC50 are at least 20 × lower than the IC50 displayed by cisplatin (15.4 μM) in HCT116 cell line while displaying at the same time, much reduced cytotoxicity in a normal dermal fibroblast culture. These cytotoxic activities seem to be correlated with the inclination angles of 2-quin unit to the central pyridine. Interestingly, all complexes can interact with calf-thymus DNA (CT-DNA) in vitro via different mechanisms, although intercalation seems to be the preferred mechanism at least for 2 and 3 at higher concentrations of DNA. Moreover, circular dichroism (CD) data seems to indicate that complex 3, more planar, induces a high destabilization of the DNA double helix (shift from B-form to Z-form). Higher the deviation from planar, the lower the cytotoxicity displayed by the complexes. Cellular uptake may be also responsible for the different cytotoxicity exhibited by complexes with 3 > 2 >1. Complex 2 seems to enter cells more passively while complex 1 and 3 might enter cells via energy-dependent and -independent mechanisms. Complexes 1–3 were shown to induce ROS are associated with the increased apoptosis and autophagy. Moreover, all complexes dissipate the mitochondrial membrane potential leading to an increased BAX/BCL-2 ratio that triggered apoptosis. Complexes 2 and 3 were also shown to exhibit an anti-angiogenic effect by significantly reduce the number of newly formed blood vessel in a CAM model with no toxicity in this in vivo model. Our results seem to suggest that the increased cytotoxicity of complex 3 in HCT116 cells and its potential interest for further translation to pre-clinical mice xenografts might be associated with: 1) higher % of internalization of HCT116 cells via energy-dependent and -independent mechanisms; 2) ability to intercalate DNA and due to its planarity induced higher destabilization of DNA; 3) induce intracellular ROS that trigger apoptosis and autophagy; 4) low toxicity in an in vivo model of CAM; 5) potential anti-angiogenic effect.publishersversionpublishe

    Comparative Analysis of Viperidae Venoms Antibacterial Profile: a Short Communication for Proteomics

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    Bacterial infections involving multidrug-resistant strains are one of the ten leading causes of death and an important health problem in need for new antibacterial sources and agents. Herein, we tested and compared four snake venoms (Agkistrodon rhodostoma, Bothrops jararaca, B. atrox and Lachesis muta) against 10 Gram-positive and Gram-negative drug-resistant clinical bacteria strains to identify them as new sources of potential antibacterial molecules. Our data revealed that, as efficient as some antibiotics currently on the market (minimal inhibitory concentration (MIC) = 1–32 μg mL−1), A. rhodostoma and B. atrox venoms were active against Staphylococcus epidermidis and Enterococcus faecalis (MIC = 4.5 μg mL−1), while B. jararaca inhibited S. aureus growth (MIC = 13 μg ml−1). As genomic and proteomic technologies are improving and developing rapidly, our results suggested that A. rhodostoma, B. atrox and B. jararaca venoms and glands are feasible sources for searching antimicrobial prototypes for future design new antibiotics against drug-resistant clinical bacteria. They also point to an additional perspective to fully identify the pharmacological potential of these venoms by using different techniques
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