102 research outputs found
Integrated dual-color InGaN light-emitting diode array through transfer printing
We demonstrate an integrated dual-color InGaN light-emitting diode (LED) array by transfer printing blue LED structures from their silicon growth substrate in between the pixels of a pre-processed green LED array on a sapphire substrate
MEtop - a generator for single top production via FCNC interactions
We present a generator for single top quark production via flavour-changing
neutral currents. The MEtop event generator allows for Next-to-Leading-Order
direct top production and Leading-Order production of several other
single top processes. A few packages with definite sets of dimension six
operators are available. We discuss how to improve the bounds on the effective
operators and how well new physics can be probed with each set of independent
dimension six operators.Comment: 26 pages, 22 figure
Clinical effectiveness of Enneking appropriate versus Enneking inappropriate procedure in patients with primary osteosarcoma of the spine: a systematic review with meta-analysis
Purpose Primary osteosarcoma of the spine is a rare osseous tumour. En bloc resection, in contrast to intralesional resection, is the only procedure able to provide Enneking appropriate (EA) margins, which has improved local control and survival of patients with primary osteosarcoma of the spine. The objective of this study is to compare the risk of local recurrence, metastases development and survival in patients with primary osteosarcoma of the spine submitted to Enneking appropriate (EA) and Enneking inappropriate (EI) procedures. Methods A systematic search was performed on EBSCO, PubMed and Web of Science, between 1966 and 2018, to identify studies evaluating patients submitted to resection of primary osteosarcoma of the spine. Two reviewers independently assessed all reports. The outcomes were local recurrence, metastases development and survival at 12, 24 and 60 months. Results Five studies (108 patients) were included for systematic review. These studies support the conclusion that EA procedure has a lower local recurrence rate (RR 0.33, 95% CI 0.17-0.66), a lower metastases development rate (RR 0.39, 95% CI 0.17-0.89) and a higher survival rate at 24 months (RR 1.78, 95% CI 1.24-2.55) and 60 months (RR 1.97, 95% CI 1.14-3.42) of follow-up; however, at 12 months, there is a non-significant difference. Conclusions EA procedure increases the ratio of remission and survival after 24 months of follow-up. Multidisciplinary oncologic groups should weigh the morbidity of an en bloc resection, knowing that in the first year the probability of survival is the same for EA and EI procedures. Graphic abstract These slides can be retrieved under Electronic Supplementary Material
A prediction rule to stratify mortality risk of patients with pulmonary tuberculosis
Tuberculosis imposes high human and economic tolls, including in Europe. This study was conducted to develop a severity assessment tool for stratifying mortality risk in pulmonary tuberculosis (PTB) patients. A derivation cohort of 681 PTB cases was retrospectively reviewed to generate a model based on multiple logistic regression analysis of prognostic variables with 6-month mortality as the outcome measure. A clinical scoring system was developed and tested against a validation cohort of 103 patients. Five risk features were selected for the prediction model: hypoxemic respiratory failure (OR 4.7, 95% CI 2.8-7.9), age >= 50 years (OR 2.9, 95% CI 1.7-4.8), bilateral lung involvement (OR 2.5, 95% CI 1.44.4), >= 1 significant comorbidity-HIV infection, diabetes mellitus, liver failure or cirrhosis, congestive heart failure and chronic respiratory disease-(OR 2.3, 95% CI 1.3-3.8), and hemoglobin = 6) mortality risk. The mortality associated with each group was 2.9%, 22.9% and 53.9%, respectively. The model performed equally well in the validation cohort. We provide a new, easy-to-use clinical scoring system to identify PTB patients with high-mortality risk in settings with good healthcare access, helping clinicians to decide which patients are in need of closer medical care during treatment.This work was supported by Fundacao Amelia de Mello/Jose de Mello Saude and Sociedade Portuguesa de Pneumologia (SPP). This work was developed under the scope of the project NORTE-01-0145-FEDER-000013, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER). NSO is a FCT (Fundacao para a Ciencia e Tecnologia) investigator. MS is an Associate FCT Investigator. The fundershad no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
Atribuciones causales y nivel educativo familiar en la comprensión del desempeño escolar en alumnos portugueses
Este artigo analisa o contributo específico do nível educativo familiar e das atribuições causais para o bom e fraco rendimento escolar dos alunos na explicação do seu desempenho nas disciplinas de Língua Portuguesa e de Matemática numa amostra de 2.082 alunos do ensino público de 11 escolas de Portugal, incluindo as Regiões Autónomas dos Açores e da Madeira. As atribuições causais foram avaliadas por meio do Questionário das Atribuições Causais para os
Resultados Escolares (QARE). O nível educativo familiar foi estimado levando em conta o nível escolar do progenitor com maior habilitação escolar. As classificações obtidas pelos alunos nas disciplinas de língua portuguesa e matemática foram também examinadas. Os resultados apontam para correlações estatisticamente significativas, destacando as atribuições na capacidade para a explicação do rendimento escolar, situação que contrasta com a atribuição dos níveis de rendimento a variáveis externas ao aluno. A análise de regressão permite associar 34,5% da variância no rendimento
conjunto em Língua Portuguesa e em Matemática no ensino básico, assim como 21,3% no ensino secundário, às
dimensões atribucionais e ao nível educativo familiar. Implicações educacionais são derivadas a partir dos achados.This paper analyzes the contribution of both family educational level and causal attributions in explaining students´
academic performance in Mathematics and Portuguese Language in a sample of 2.082 public school students from mainland Portugal and the Azores and Madeira regions. Causal attributions were assessed by the Causal Attributions Questionnaire for School Results (QARE). The family educational level was estimated taking into account the educational
level of the parent with higher academic degree. The academic grades obtained by students in mathematics and portuguese language were also considered. The results show statistically significant correlations between variables. Internal causal attributions such as capacity and study methods were predominant to explain school performance in the sample and stood out in contrast to external attributions explanations. Regression analyses revealed that 34.5% of the
variance in the combined achievement on Portuguese Language and Mathematics in primary education and 21.3% in secondary education could be explained by both the attributional dimensions and family education level. Some educational implications are present taking these data.Este artículo analiza la contribución específica del nivel educativo familiar y de las atribuciones causales para el buen y el
flaco rendimiento escolar de los alumnos en la explicación de su desempeño en las disciplinas de Lengua Portuguesa y
Matemáticas en una muestra de 2.082 alumnos de enseñanza pública de 11 escuelas de Portugal, incluyendo las Regiones
Autónomas de Açores y Madeira. Las atribuciones causales fueron evaluadas por medio del “Questionário das Atribuições Causais para os Resultados Escolares” (QARE). El nivel educativo familiar fue estimado teniendo en cuenta el nivel escolar del progenitor con mayor habilitación escolar. Las clasificaciones obtenidas por los alumnos en las disciplinas de lengua portuguesa y matemáticas fueron también examinadas. Los resultados señalaron correlaciones
estadísticamente significativas, destacando las atribuciones en la capacidad para la explicación del rendimiento escolar,
situación que contrasta con la atribución de los niveles de rendimiento a variables externas al alumno. El análisis de regresión permite asociar 34.5% de la variancia en el rendimiento conjunto de la Lengua Portuguesa y las Matemáticas en la enseñanza básica, así como 21.3% en la enseñanza secundaria, a las dimensiones de atribución y al nivel educativo familiar. Implicaciones educacionales son derivadas a partir de los hallazgos.Editora Universitária São Francisc
Optimization of Time-Course Experiments for Kinetic Model Discrimination
Systems biology relies heavily on the construction of quantitative models of biochemical networks. These models must have predictive power to help unveiling the underlying molecular mechanisms of cellular physiology, but it is also paramount that they are consistent with the data resulting from key experiments. Often, it is possible to find several models that describe the data equally well, but provide significantly different quantitative predictions regarding particular variables of the network. In those cases, one is faced with a problem of model discrimination, the procedure of rejecting inappropriate models from a set of candidates in order to elect one as the best model to use for prediction
A study protocol to evaluate the relationship between outdoor air pollution and pregnancy outcomes
<p>Abstract</p> <p>Background</p> <p>The present study protocol is designed to assess the relationship between outdoor air pollution and low birth weight and preterm births outcomes performing a semi-ecological analysis. Semi-ecological design studies are widely used to assess effects of air pollution in humans. In this type of analysis, health outcomes and covariates are measured in individuals and exposure assignments are usually based on air quality monitor stations. Therefore, estimating individual exposures are one of the major challenges when investigating these relationships with a semi-ecologic design.</p> <p>Methods/Design</p> <p>Semi-ecologic study consisting of a retrospective cohort study with ecologic assignment of exposure is applied. Health outcomes and covariates are collected at Primary Health Care Center. Data from pregnant registry, clinical record and specific questionnaire administered orally to the mothers of children born in period 2007-2010 in Portuguese Alentejo Litoral region, are collected by the research team. Outdoor air pollution data are collected with a lichen diversity biomonitoring program, and individual pregnancy exposures are assessed with spatial geostatistical simulation, which provides the basis for uncertainty analysis of individual exposures. Awareness of outdoor air pollution uncertainty will improve validity of individual exposures assignments for further statistical analysis with multivariate regression models.</p> <p>Discussion</p> <p>Exposure misclassification is an issue of concern in semi-ecological design. In this study, personal exposures are assigned to each pregnant using geocoded addresses data. A stochastic simulation method is applied to lichen diversity values index measured at biomonitoring survey locations, in order to assess spatial uncertainty of lichen diversity value index at each geocoded address. These methods assume a model for spatial autocorrelation of exposure and provide a distribution of exposures in each study location. We believe that variability of simulated exposure values at geocoded addresses will improve knowledge on variability of exposures, improving therefore validity of individual exposures to input in posterior statistical analysis.</p
Assimetrias regionais. Que diferenças nos estilos de vida e na satisfação com a vida dos adolescentes? Um estudo realizado em alunos do 3º ciclo do Ensino Básico em Portugal
Applications of yeast flocculation in biotechnological processes
A review on the main aspects associated with yeast flocculation and its application
in biotechnological processes is presented. This subject is addressed following three
main aspects – the basics of yeast flocculation, the development of “new” flocculating yeast
strains and bioreactor development. In what concerns the basics of yeast flocculation, the
state of the art on the most relevant aspects of mechanism, physiology and genetics of yeast
flocculation is reported. The construction of flocculating yeast strains includes not only the
recombinant constitutive flocculent brewer’s yeast, but also recombinant flocculent yeast
for lactose metabolisation and ethanol production. Furthermore, recent work on the
heterologous β-galactosidase production using a recombinant flocculent Saccharomyces
cerevisiae is considered. As bioreactors using flocculating yeast cells have particular properties,
mainly associated with a high solid phase hold-up, a section dedicated to its operation is
presented. Aspects such as bioreactor productivity and culture stability as well as bioreactor
hydrodynamics and mass transfer properties of flocculating cell cultures are considered.
Finally, the paper concludes describing some of the applications of high cell density
flocculation bioreactors and discussing potential new uses of these systems.Fundação para a Ciência e a Tecnologia (FCT) – PRAXIS XXI - BD11306/97
Integrated monitoring of mola mola behaviour in space and time
Over the last decade, ocean sunfish movements have been monitored worldwide using various satellite tracking methods. This study reports the near-real time monitoring of finescale (< 10 m) behaviour of sunfish. The study was conducted in southern Portugal in May 2014 and involved satellite tags and underwater and surface robotic vehicles to measure both the movements and the contextual environment of the fish. A total of four individuals were tracked using custom-made GPS satellite tags providing geolocation estimates of fine-scale resolution. These accurate positions further informed sunfish areas of restricted search (ARS), which were directly correlated to steep thermal frontal zones. Simultaneously, and for two different occasions, an Autonomous Underwater Vehicle (AUV) videorecorded the path of the tracked fish and detected buoyant particles in the water column. Importantly, the densities of these particles were also directly correlated to steep thermal gradients. Thus, both sunfish foraging behaviour (ARS) and possibly prey densities, were found to be influenced by analogous environmental conditions. In addition, the dynamic structure of the water transited by the tracked individuals was described by a Lagrangian modelling approach. The model informed the distribution of zooplankton in the region, both horizontally and in the water column, and the resultant simulated densities positively correlated with sunfish ARS behaviour estimator (r(s) = 0.184, p < 0.001). The model also revealed that tracked fish opportunistically displace with respect to subsurface current flow. Thus, we show how physical forcing and current structure provide a rationale for a predator's finescale behaviour observed over a two weeks in May 2014
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