343 research outputs found

    Perfis proteicos e desempenho fisiológico de sementes de café submetidas a diferentes métodos de processamento e secagem.

    Get PDF
    O objetivo deste trabalho foi avaliar os perfis proteicos e o desempenho fisiológico de sementes de café submetidas a diferentes métodos de processamento e secagem. Foram avaliados os processamentos por via seca e úmida, e as secagens natural, em terreiro, e artificial a 60ºC, ou a 60ºC até 30% de umidade e 40ºC até teor final de 11% (base úmida). Após serem processadas e secadas, as sementes foram avaliadas quanto ao desempenho fisiológico e submetidas a análises bioquímicas, por meio da eletroforese de proteínas resistentes ao calor LEA (?late embryogenesis abundant?) e das enzimas superóxido dismutase, catalase, peroxidase, esterase, polifenoloxidase, isocitrato desidrogenase, álcool desidrogenase e malato desidrogenase. O perfil proteico de sementes de café é afetado pelo método de processamento e de secagem. Os cafés processados por via úmida apresentam maior tolerância à secagem ? revelada pela maior atividade de enzimas antioxidativas e pelo melhor desempenho fisiológico ? do que os processados por via seca. A atividade de proteínas resistentes ao calor e de enzimas antioxidantes é variável promissora para diferenciar a qualidade dos cafés submetidos a diferentes manejos pós‑colheita

    Synonymous Substitution Rates Predict HIV Disease Progression as a Result of Underlying Replication Dynamics

    Get PDF
    Upon HIV transmission, some patients develop AIDS in only a few months, while others remain disease free for 20 or more years. This variation in the rate of disease progression is poorly understood and has been attributed to host genetics, host immune responses, co-infection, viral genetics, and adaptation. Here, we develop a new “relaxed-clock” phylogenetic method to estimate absolute rates of synonymous and nonsynonymous substitution through time. We identify an unexpected association between the synonymous substitution rate of HIV and disease progression parameters. Since immune activation is the major determinant of HIV disease progression, we propose that this process can also determine viral generation times, by creating favourable conditions for HIV replication. These conclusions may apply more generally to HIV evolution, since we also observed an overall low synonymous substitution rate for HIV-2, which is known to be less pathogenic than HIV-1 and capable of tempering the detrimental effects of immune activation. Humoral immune responses, on the other hand, are the major determinant of nonsynonymous rate changes through time in the envelope gene, and our relaxed-clock estimates support a decrease in selective pressure as a consequence of immune system collapse

    Career self: a longitudinal study with college students

    Get PDF
    O self de carreira constituí um subconjunto organizado do universo cognitivo de uma pessoa, responsável pelo carácter subjetivo que a mesma confere à carreira. Este estudo pretende avaliar mudanças no conteúdo do self de carreira de estudantes universitários, do início para o final do último ano de graduação. Para tal, recorreu-se a medidas repetidas dos índices da Grelha de Repertório da Carreira (Silva & Taveira, 2005; Silva, 2008). Na investigação, participaram 80 estudantes, dos quais 49 são mulheres (61,25%) e 31 são homens (38,75%), com idades entre os 21 e os 45 anos (M= 23,9, DP= 4,31). Os resultados indicam que, no final da licenciatura, os estudantes diminuem a distância como se constrõem em relação aos outros e mantêm uma construção positiva do self de carreira.Fundação para a Ciência e a Tecnologia (FCT

    Eco-efficiency of forestry companies around the world: a data envelopment analysis.

    Get PDF
    Objective: to evaluate and compare the economic, environmental, and eco-efficiency of companies operating in the forestry sector and fill the gap in relation to the lack of information about the theme. Theoretical framework: increased awareness of society around the traditional productive model and its impact on the environment demands that companies associate business competitiveness with environmental responsibility. Therefore, the disclosure of information and the analysis of it using methods such as the eco-efficiency approach are important to monitor the performance of companies. Methods: the Data Envelopment Analysis method was used with three proposed models: economic (desirable output); environmental with undesirable variables; and eco-efficiency model with desirable and undesirable variables. Results and conclusions: results show that the years 2009-2010 and 2016-2017 were more favorable to technical efficiency, while ecological efficiency was higher from 2010 to 2012. Meanwhile, the highest average eco-efficiency score was registered in 2013. In the 11 years analyzed, Portugal, Canada, United Kingdom, Australia, South Africa, and Spain stood out as the most eco-efficient countries. Research implications: the eco-efficiency approach demonstrated and discussed in this research can be used to monitor forestry companies' performance taking into account their productivity and environmental impact reduction. Originality/value: this study presents a comprehensive evaluation of silviculture companies worldwide using the technical, environmental, and eco-efficiency models. Analyses are based on financial and environmental data of 82 publicly listed companies from 23 countries, including developed and developing economies and cover the period of 11 years (2009 to 2019)

    Independent validation of CT radiomics models in colorectal liver metastases:predicting local tumour progression after ablation

    Get PDF
    Objectives:Independent internal and external validation of three previously published CT-based radiomics models to predict local tumor progression (LTP) after thermal ablation of colorectal liver metastases (CRLM). Materials and methods: Patients with CRLM treated with thermal ablation were collected from two institutions to collect a new independent internal and external validation cohort. Ablation zones (AZ) were delineated on portal venous phase CT 2–8 weeks post-ablation. Radiomics features were extracted from the AZ and a 10 mm peri-ablational rim (PAR) of liver parenchyma around the AZ. Three previously published prediction models (clinical, radiomics, combined) were tested without retraining. LTP was defined as new tumor foci appearing next to the AZ up to 24 months post-ablation. Results: The internal cohort included 39 patients with 68 CRLM and the external cohort 52 patients with 78 CRLM. 34/146 CRLM developed LTP after a median follow-up of 24 months (range 5–139). The median time to LTP was 8 months (range 2–22). The combined clinical-radiomics model yielded a c-statistic of 0.47 (95%CI 0.30–0.64) in the internal cohort and 0.50 (95%CI 0.38–0.62) in the external cohort, compared to 0.78 (95%CI 0.65–0.87) in the previously published original cohort. The radiomics model yielded c-statistics of 0.46 (95%CI 0.29–0.63) and 0.39 (95%CI 0.28–0.52), and the clinical model 0.51 (95%CI 0.34–0.68) and 0.51 (95%CI 0.39–0.63) in the internal and external cohort, respectively. Conclusion: The previously published results for prediction of LTP after thermal ablation of CRLM using clinical and radiomics models were not reproducible in independent internal and external validation. Clinical relevance statement: Local tumour progression after thermal ablation of CRLM cannot yet be predicted with the use of CT radiomics of the ablation zone and peri-ablational rim. These results underline the importance of validation of radiomics results to test for reproducibility in independent cohorts. </p

    Óleos essenciais de plantas brasileiras

    Get PDF
    As part of a chemical survey of brazilian plants, we report the presence of essential oils in the wood of Dicypellium caryophyllatum Nees (Lauraceae), composition: eugenol 95,5%, O-methyleugenol 1,6%; the leaves of Myrcia polyantha D.C., var. coriacea Bg. (Myrtaceae), yield: 2%, composition: limonene 4,5%, neral 28,0%, geranial 50,2%, sesquiterpenes 14,6%; the bark of Parkia oppositifolia Spr. ex Benth. (Leguminosae-Mimosoideae). composition: methyl salicylate 98,2%; the trunk wood of Dalbergia decipularis Rizz. et Mattos (Leguminosae-Papilionatae), composition: nerolidol 97,2%; the trunk wood of Poecilanthe parviflora Benth. (Leguminosae-Papilionatae), composition: nerolidol 26,0%; the leaves of Piper cavalcautei Yuncker (Piperaceae), yield: 1.9%, composition: safrol 69,0% methyleugenol 8,0% terpenes 23,0%.Como parte de um estudo químico de plantas brasileiras, comunica-se a presença de óleos essenciais na madeira de Dicypellium caryophyllatum Nees (Lauraceae), de composiçãoeugenol 95,5% O-metileugenol 1,6%; as fôlhas de Myrcia polyantha D.C., var. coriácea Bg. (Myrtaceae), com um rendimento de 2%, de composiçãolimoneno 4,5%, nera 128,0%, geranial 40,2%, sesquiterpenos 14,6%; a casca de Parkia oppositifolia Spr. ex Benth. (Leguminose-mimoeoidaeae), de composiçãosalicilato de metila 98,2%; a madeira do tronco de Dalbergia decipuiaris Rizz. et Mattos (Leguminosae-Papilionatae), de composiçãonerolidol 97,2%; a madeira do tronco de Poecilanthe parviflora Benth. (Leguminosae-Papilionatae)nerolidol 26,0%; as fôlhas de Piper cavalcantei Yuncker (Piperaceae), rendimento 1,9% de composiçãosafrol 69,0%, metileugenol 8,0%, terpenos 23,0%

    Psychologists’ dilemmas in career counselling practice

    Get PDF
    In this study, we explored main dilemmas psychologists face in career counselling in two main professional settings: employment and education. Participants included 24 experienced Portuguese psychologists, working in employment (n = 14) and educational (n = 10) settings. We used consensual qualitative research to conduct and analyse semi-structured interviews. Results revealed dilemmas’ in five domains: neutrality, assessment, dual loyalty, role boundaries, and confidentiality, with the typical dilemma in the domain of neutrality. Differences between groups were found in the domains of dual loyalty and role boundaries.Dans cette étude, nous avons exploré les principaux dilemmes rencontrés par les psychologues dans le conseil en orientation dans deux milieux professionnels centraux: le placement et l’éducation. Parmi les participants figuraient 24 psychologues portugais expérimentés travaillant dans des contextes de placement (n = 14) et d’éducation (n = 10). Nous avons utilisé la recherche qualitative consensuelle pour mener et analyser les entretiens semi-structurés. Les re´sultats ont révé lé des dilemmes dans cinq domaines: la neutralité, l’évaluation, la double loyauté, les limites du rôle, et la confidentialité, avec le dilemme typique dans le domaine de la neutralité. Les différences entre les groupes ont été identifiees dans les domaines de la double loyauté et les limites du rôle.In dieser Studie untersuchten wir die hauptsä chlichen Dilemmata, mit denen Psychologen in der Berufsberatung in zwei wesentlichen professionellen Einrichtungen konfrontiert sind: Beruf und Bildung. Zu den Teilnehmern geho ¨rten 24 erfahrene portugiesische Psychologen, die in Einrichtungen von Beruf (n = 14) und Bildung (n = 10) arbeiteten. Wir verwendeten einvernehmliche qualitative Forschung um semi-strukturierte Interviews durchzufu¨hren und zu analysieren. Die Ergebnisse zeigten Dilemmata in fünf Bereichen: Neutralität, Beurteilung, doppelte Loyalität, Rollengrenzen und Vertraulichkeit, mit dem typischen Dilemma in der Domäne der Neutralität. Unterschiede zwischen den Gruppen wurden in den Bereichen der doppelten Loyalität und Rollengrenzen gefunden

    Spread of yellow fever virus outbreak in Angola and the Democratic Republic of the Congo 2015-16: a modelling study.

    Get PDF
    BACKGROUND: Since late 2015, an epidemic of yellow fever has caused more than 7334 suspected cases in Angola and the Democratic Republic of the Congo, including 393 deaths. We sought to understand the spatial spread of this outbreak to optimise the use of the limited available vaccine stock. METHODS: We jointly analysed datasets describing the epidemic of yellow fever, vector suitability, human demography, and mobility in central Africa to understand and predict the spread of yellow fever virus. We used a standard logistic model to infer the district-specific yellow fever virus infection risk during the course of the epidemic in the region. FINDINGS: The early spread of yellow fever virus was characterised by fast exponential growth (doubling time of 5-7 days) and fast spatial expansion (49 districts reported cases after only 3 months) from Luanda, the capital of Angola. Early invasion was positively correlated with high population density (Pearson's r 0·52, 95% CI 0·34-0·66). The further away locations were from Luanda, the later the date of invasion (Pearson's r 0·60, 95% CI 0·52-0·66). In a Cox model, we noted that districts with higher population densities also had higher risks of sustained transmission (the hazard ratio for cases ceasing was 0·74, 95% CI 0·13-0·92 per log-unit increase in the population size of a district). A model that captured human mobility and vector suitability successfully discriminated districts with high risk of invasion from others with a lower risk (area under the curve 0·94, 95% CI 0·92-0·97). If at the start of the epidemic, sufficient vaccines had been available to target 50 out of 313 districts in the area, our model would have correctly identified 27 (84%) of the 32 districts that were eventually affected. INTERPRETATION: Our findings show the contributions of ecological and demographic factors to the ongoing spread of the yellow fever outbreak and provide estimates of the areas that could be prioritised for vaccination, although other constraints such as vaccine supply and delivery need to be accounted for before such insights can be translated into policy. FUNDING: Wellcome Trust
    corecore