Systematic review of worldwide variations of the prevalence of wheezing symptoms in children

Background: Considerable variation in the prevalence of childhood asthma and its symptoms (wheezing) has been observed in previous studies and there is evidence that the prevalence has been increasing over time. Methods: We have systematically reviewed the reported prevalence and time trends of wheezing symptoms among children, worldwide and within the same country over time. All studies comprising more than 1000 persons and meeting certain other quality criteria published over a 16-year period, between January 1990 and December 2005, are reported and a comparison of ISAAC (International Study of Asthma and Allergies in Childhood) and non-ISAAC studies is made, in part as a way of expanding the power to examine time trends (the older studies tend to be non-ISAAC), but also to examine possible methodological differences between ISAAC and non-ISAAC questions. Results: A wide range of current prevalence of wheeze was observed between and within countries over time. The UK had the highest recorded prevalence of 32.2% in children aged 13–14 in 1994–5 and Ethiopia had the lowest prevalence, 1.7% in children aged 10–19 in 1996. All studies in Australia and the UK were compared using multiple logistic regression. ISAAC phase I and III studies reported significantly higher prevalence of current wheeze (OR = 1.638) compared with non-ISAAC studies, after adjusting for various other factors (country, survey year, age of child, parental vs child response to the survey). Australia showed a significantly higher prevalence of current wheezing (OR = 1.343) compared with the UK, there was a significant increase in the prevalence odds ratio per survey year (2.5% per year), a significant decrease per age of child (0.7% per year), and a significantly higher response in current wheezing if the response was self-completed by the child (OR = 1.290). These factors, when explored separately for ISAAC and non-ISAAC studies, showed very different results. In ISAAC studies, or non-ISAAC studies using ISAAC questions, there was a significant decrease in current wheezing prevalence over time (2.5% per year). In non-ISAAC studies, which tend to cover an earlier period, there was a significant increase (2.6% per year) in current wheezing prevalence over time. This is very likely to be a result of prevalence of wheezing increasing from the 1970s up to the early 1990s, but decreasing since then. Conclusion: The UK has the highest recorded prevalence of wheezing and Ethiopia the lowest. Prevalence of wheezing in Australia and the UK has increased from the 1970s up to the early 1990s, but decreased since then and ISAAC studies report significantly higher prevalences than non-ISAAC studies.

Development and clinical validation of a loop-mediated isothermal amplification (LAMP) method for the rapid detection of Neisseria meningitidis

Loop-mediated isothermal amplification (LAMP) is an innovative technique that allows the rapid detection of target nucleic acid sequences under isothermal conditions without the need for complex instrumentation. The development, optimization, and clinical validation of a LAMP assay targeting the ctrA gene for the rapid detection of capsular Neisseria meningitidis were described. Highly specific detection of capsular N. meningitidis type strains and clinical isolates was demonstrated, with no cross-reactivity with other Neisseria spp. or with a comprehensive panel of other common human pathogens. The lower limit of detection was 6 ctrA gene copies detectable in 48 min, with positive reactions readily identifiable visually via a simple color change. Higher copy numbers could be detected in as little as 16 min. When applied to a total of 394 clinical specimens, the LAMP assay in comparison to a conventional TaqMan® based real-time polymerase chain reaction system demonstrated a sensitivity of 100% and a specificity of 98.9% with a ? coefficient of 0.942. The LAMP method represents a rapid, sensitive, and highly specific technique for the detection of N. meningitidis and has the potential to be used as a point-of-care molecular test and in resource-poor settings.

In vitro testing of Advanced JAX (TM) Bone Void Filler System: species differences in the response of bone marrow stromal cells to beta tri-calcium phosphate and carboxymethylcellulose gel

The Advanced JAX (TM) Bone Void Filler System (AJBVFS) is a novel bone graft material manufactured by Smith and Nephew Orthopaedics Ltd. and comprises beta tri-calcium phosphate granules with carboxymethylcellulose (CMC) gel as a handling agent. This study investigated the potential, in vitro, of the AJBVFS to function as a delivery system for cell therapy to enhance healing of bone defects. The attachment of rabbit bone marrow stromal cells (rbBMSCs), human BMSCs (hBMSCs) and human bone-derived cells (hBDCs) to JAX (TM) granules and the effect of CMC gel on cell proliferation and differentiation were investigated. There were slight species differences in the number and morphology of cells attached on the JAX (TM) granules with less rbBMSC attachment than human. All cells tolerated the presence of CMC gel and a reduction in cell number was only seen after longer exposure to higher gel concentrations. Low concentrations of CMC gel enhanced proliferation, alkaline phosphatase (ALP) expression and ALP activity in human cells but had no effect on rbBMSC. This study suggests that AJBVFS is an appropriate scaffold for the delivery of osteogenic cells and the addition of CMC gel as a handling agent promotes osteogenic proliferation and differentiation and is therefore likely to encourage bone healing.

Web 2.0, PC e EFA: impactes de uma oficina de formação de professores

As competências em Tecnologia da Informação e Comunicação (TIC) e o Pensamento Crítico (PC) são duas das linhas orientadoras da Aprendizagem ao Longo da Vida (ALV) que reconhecendo que todos os contextos (informais, não-formais e formais) podem ser de aprendizagem, assumiram no quadro da Educação e Formação de Adultos (EFA), em Portugal, uma expressividade plasmada no Referencial de Competências-Chave de Educação e Formação de Adultos, nível secundário (EFA-NS). Contudo a orientação PC/TIC não tem sido explicitamente conciliada nas práticas de educação e formação de adultos. Neste contexto desenvolveu-se uma Oficina de Formação para professores/formadores de cursos EFA-NS, na qual se trabalhou a integração de ferramentas da Web 2.0 com a infusão de PC em materiais/atividades para cursos EFA-NS. No desenvolvimento da Oficina foram consideradas três vertentes. Primeira, conceções dos professores sobre EFA/TIC e EFA/PC. Segunda, a formação sobre PC/TIC. Terceira, produção e implementação de materiais/atividades com orientação PC/TIC. A componente de trabalho autónomo da Oficina passou essencialmente pela dinâmica de uma comunidade online de nome EF@. O grupo de formação era constituído por 17 professores do ensino secundário, e pela investigadora/formadora, autora deste estudo. Acrescente-se que no conjunto das 10 sessões de trabalho presencial a investigadora/formadora foi coadjuvada por mais três formadores. Estudar os impactes da Oficina no desenvolvimento profissional dos professores, conjuntamente com a avaliação da influência dos materiais/atividades produzidos (na Oficina) no nível de PC dos alunos, assumiram-se como as duas questões de investigação a que este estudo pretendeu dar resposta. Neste sentido estudámos o grupo de professores em formação – estudo de caso – e o grupo de alunos – plano quasi experimental do tipo grupo de controlo/experimental, pré/pós-teste, pelo que o enquadramento da metodologia num estudo misto, predominantemente de natureza qualitativa, foi a adotada. A recolha e o tratamento de dados foram feitos mediante várias técnicas – observação, inquérito, análise e testagem – associadas a diferentes instrumentos: dois questionários, diário de investigador e Teste de Pensamento Crítico – Cornell (Nível X). A análise dos dados recolhidos possibilitou a compreensão de como a Oficina contribui para a reflexão: (i) nas práticas anteriores dos professores; (ii) nas competências adquiridas na Oficina e (iii) nas práticas implementadas. Ao nível do PC dos alunos, podemos dizer que os materiais/atividades produzidos na Oficina influenciaram o nível de PC dos alunos, já que os resultados da média do PC do pós-teste foram estatisticamente significativos para o grupo experimental, quando comparado com a média do PC no grupo de controlo.

Representações/expectativas sobre o processo de reconhecimento, validação e certificação de competências (RVCC): da utopia à realidade

O Programa Novas Oportunidades valoriza a Aprendizagem ao Longo da Vida (ALV). Algumas pessoas que abandonaram a escola vêem, na actualidade, certificadas as suas competências, ao frequentarem o Processo RVCC. Através do estudo ―Representações/Expectativas sobre o Processo de Reconhecimento, Validação e Certificação de Competências (RVCC): Da utopia à realidade, pretendemos saber as representações/expectativas iniciais que os sujeitos possuíam e se estas, no final, se viram confirmadas. As opiniões sobre o processo, após a sua conclusão, foi um dos vectores tido em atenção. Verificou-se que, de entre as várias motivações para a inscrição no processo RVCC, as principais se prendem com a vontade dos adultos continuarem os estudos depois de terem parado, o desejo de aprenderem mais/saber coisas novas, a Progressão no emprego e Mais possibilidades de escolher o tipo de emprego. As razões da opção pelo processo RVCC fundamentam-se no facto de se tratar de um Processo de valorização de conhecimentos e por ser rápido, havendo outras razões menos abordadas. As relacionadas com a sua rapidez e facilidade encontram-se depen-dentes, respectivamente, das variáveis idade e género. A valorização profissional e a progressão nos estudos constituem as principais expectativas que os sujeitos possuíam anteriormente. As expectativas iniciais viram-se muito (61,11%) e muitíssimo (23,15%) confirmadas. O Reconhecimento do saber experiencial e as Valorizações académica e pessoal foram aspectos importantes para que tal acontecesse. No final, os adultos opinam favoravelmente sobre o processo, enfatizando as metodologias, a gratificação sentida, a reflexão sobre as aprendizagens e a melhoria da auto- -estima. Salientam que a frequência do processo lhes trouxe mudanças académicas e pessoais. No contexto profissional são menos notórias, conquanto seja expectável que ocorram melhorias.

Influence of Different Performance Levels on Pacing Strategy During the Women's World Championship Marathon Race.

Purpose To analyse pacing strategies displayed by athletes achieving differing levels of performance during an elite level marathon race. Methods Competitors in the 2009 IAAF Women’s Marathon Championship were split into Groups 1, 2, 3, and 4 comprising the first, second, third, and fourth 25% of finishers respectively. Final, intermediate, and personal best (PB) times of finishers were converted to mean speeds, and relative speed (% of PB speed) was calculated for intermediate segments. Results Mean PB speed decreased from Group 1 to 4 and speed maintained in the race was 98.5 + 1.8%, 97.4 + 3.2%, 95.0 + 3.1% and 92.4 + 4.4% of PB speed for Groups 1-4 respectively. Group 1 was fastest in all segments and differences in speed between groups increased throughout the race. Group 1 ran at lower relative speeds than other groups for the first two 5 km segments, but higher relative speeds after 35km. Significant differences (P<0.01) in the percentage of PB speed maintained were observed between Groups 1 and 4, and 2 and 4 in all segments after 20 km, and Groups 3 and 4 from 20-25 km and 30-35 km. Conclusions Group 1 athletes achieved superior finishing times relative to their PB than athletes in other Groups who selected unsustainable initial speeds resulting in subsequent significant losses of speed. It is suggested that psychological factors specific to a major competitive event influenced decision making by athletes and poor decisions resulted in final performances inferior to those expected based on PB times.

Sustainability Evaluation of Biodiesel Produced from Microalgae Chlamydomonas sp Grown in Brewery Wastewater

This study performs a sustainability evaluation of biodiesel from microalga Chlamydomonas sp. grown in 20 % (v/v) of brewery’s wastewater, blended with pentose sugars (xylose, arabinose or ribose resulting from the hydrolysis of brewer’s spent grains (BSG). The life cycle steps considered for the study are: microalgae cultivation, biomass processing and lipids extraction at the brewery site, and its conversion to biodiesel at a dedicated external biofuel’s plant. Three sustainability indicators (LCEE, FER and GW) were considered and calculated using experimental data. Literature data was used, whenever necessary, to complement life cycle data, thus allowing a more accurate sustainability evaluation. A comparative analysis of the biodiesel life cycle steps was also conducted, with the main goal of identifying which steps need to be improved. Results show that biomass processing, especially cell harvesting, microalgae cultivation, and lipids extraction are the main process bottlenecks. It is also analysed the influence on the microalgae biodiesel sustainability of adding each pentose sugar to the cultivation media, concluding that it strongly influences the biomass and lipid productivity. In particular, the addition of xylose is preferable in terms of lipid productivity, but from a sustainability point of view, ribose is the best, though the difference from xylose is not significant. Nevertheless, culture without pentose addition presents the best sustainability results.

L'Écho de Paris

1890/08/18 (Numéro 2283).

De clase

Programas, proyectos y red de portales

Adult perceptions of student involvement in schoolyard gardening /

The purpose of this research is to investigate through adult perceptions what factors have enabled and limited student participation in schoolyard gardening, and how to support student involvement in schoolyard gardening. It is a collective case study of three schools in the Toronto District School Board (TDSB, Ontario, Canada) that are currently running a schoolyard gardening project. Sixteen interviews were conducted during May and June, 2005, and photos of the three schoolyard gardens were taken. The results show that the common factors that have enabled student participation in schoolyard gardening at the three schools are teacher's initiative and commitment, principal's leadership and support, parental involvement and donations, and the TDSB's EcoSchools program and workshops. The common limiting factors are time, money, and the unions' "work-to-rule" issue. The ways to support student involvement include teachers integrating the gardening into the curriculum; parents making donations to the school and creating a family gardening culture; principals supporting in money or budget and taking the lead; the TDSB providing funding, awards, incentives, and more maintenance; and the Ontario Ministry of Education supplying funding, curriculum link, and teacher training.

Estudio fitoquímico de algas marinas con actividad biológica en larvas de Aedes aegypty (Linnaeus)

Tesis (Maestría en Ciencias con Especialidad en Química de Productos Naturales) UANL