Evolución de la cubierta vegetal después de una perturbación por deslizamientos

La perturbación produce alteraciones en los ecosistemas afectando la evolución por sucesión ecológica y, consecuentemente, es considerada como uno de los principales factores que afectan al desarrollo de la vegetación. Por ello, ejerce un papel crucial en el mantenimiento de la biodiversidad, teniendo un papel ecológico muy importante a través de la creación de hábitats complejos y únicos. Así, para la determinación del nivel de diferenciación entre sectores internos de los deslizamientos en función de la vegetación, conjuntamente con una evaluación de las alteraciones entre comunidades afectadas y adyacentes, se han analizado mediante un muestreo estratiicado, tres sectores del deslizamiento (cicatriz, cuerpo y pie), culminando en la identiicación de 115 taxones. Las laderas inestables permiten el surgimiento de especies endémicas donde el valor de conservación y la riqueza lorística es máxima en la fase intermedia del proceso de recuperación iniciado con la perturbación. La ocurrencia periódica de deslizamientos y consecuente regresión sucesional se interpreta como positiva y necesaria.info:eu-repo/semantics/publishedVersio

Características dos perfis de participação no bullying em Portugal e no Brasil: um estudo transcultural

O objetivo do presente estudo foi verificar as associações dos papéis de participação no bullying escolar com aspectos apontados pela literatura como características dos perfis desses participantes, separados pelo país de origem (Portugal e Brasil). Participaram deste estudo 789 crianças e adolescentes, com idades entre 7 e 14 anos de escolas públicas e privadas de ambos os países. Os instrumentos utilizados foram: Escala Sócio Métrica, para verificação do bullying pela indicação dos pares; KTK, para análise do desempenho motor; média final de quatro disciplinas escolares, para o desempenho escolar; Escala Subjetiva de Status Social em Sala de Aula, para o status sócio métrico; massa corporal e estatura, para o cálculo do IMC; e Escala de Silhuetas Corporais, para a satisfação corporal. Dentre os principais achados deste estudo destacase que a única variável associada aos papéis de participação no bullying em todas as análises realizadas foi o status sócio métrico. Entretanto, desempenho motor e desempenho escolar também deram indícios de serem variáveis importantes para compreensão desses papéis em algumas análises. Sexo, país de origem, idade, IMC e satisfação corporal não apresentaram nenhuma associação em todas as análises. Recomenda-se que mais estudos transculturais sejam realizados analisando as relações entre bullying e as variáveis citadas na literatura, para verificar se estes achados se confirmam e podem ser estendidos aos envolvidos no bullying nestes países como um todo.Fundos nacionais através da FCT (Fundação para a Ciência e a Tecnologia) no âmbito do projeto do CIEC (Centro de Investigação em Estudos da Criança) da Universidade do Minho, com a referência UIDB/00317/202

Hybrid CABG: an alternative for perfusion time decrease

OBJETIVO: Avaliar a possibilidade da redução do tempo de circulação extracorpórea (CEC) e das complicações relacionadas a esta variável na revascularização do miocárdio (RM), utilizando o método híbrido como alternativa. MÉTODOS: Noventa pacientes foram analisados, retrospectivamente, entre março/2000 e agosto/2006. Todos foram revascularizados com três ou mais enxertos e divididos em doisgrupos: híbrido - 45 pacientes que foram operados pela técnica híbrida; total - 45 pacientes operados com CEC. RESULTADOS: No grupo híbrido, o tempo de CEC variou de 20 a 81 minutos e, no grupo total, de 60 a 210 minutos (p<0,001). O tempo de pinçamento aórtico variou de 7 a 70 minutos no primeiro grupo e de 34 a 100 minutos (p<0,001) no segundo grupo. Foi encontrada diferença estatisticamente significativa entre os grupos em relação à incidência de fibrilação atrial e à disfunção renal. CONCLUSÃO: Utilizando-se a técnica híbrida é possível reduzir o tempo de CEC e a incidência de algumas complicações pós-operatórias. Provavelmente, esta redução nas incidências de fibrilação atrial e disfunção renal podem ser explicadas por uma redução na resposta da inflamatória conseqüente a um tempo de CEC menor.OBJECTIVE: To evaluate the decrease of CPB time and its related complications in CABG using a hybrid alternative method. METHODS: Ninety patients were retrospectively analyzed between March 2000 and August 2006. All were treated with three or more grafts and divided into two groups: Group 1 was the hybrid group - 45 patients who had been operated by the hybrid technique; Group 2 was the total group - 45 patients operated in on-pump. RESULTS: In the hybrid group, the CPB time varied from 20 min. to 81 min. In the total group, the CPB time varied from 60 min. to 210 min. (p<0.001). The aorta cross-clamping time varied in the first group from 7 min. to 70 min. In Group 2, from 34 to 100 min. (p<0.001). A statistically significant difference was found between these two groups in relation to the occurrence of postoperative atrium fibrillation and renal dysfunction. CONCLUSION: Using the hybrid technique it is possible to reduce the CPB time, as well as the occurrence of some postoperative complications. Probably, this decreasing in atrial fibrillation and renal dysfunction incidences could be explained due to a less significant inflammatory activation, which is a consequence of a shorter CPB time

Adherence to Southern European Atlantic Diet and physical fitness on the atherogenic index of plasma in adolescents

We sought (i) to evaluate the associations of cardiorespiratory fitness (CRF), muscular fitness (MF) and Southern European Atlantic Diet (SEADiet) with atherogenic index of plasma (AIP) and (ii) to investigate de combined association of MF, CRF and SEADiet on AIP in adolescents. A cross-sectional school-based study was conducted on 493 adolescents (285 girls and 208 boys) aged 15-18 years, from the Portuguese Azorean Archipelago. CRF was measured by shuttle run test and MF by curl up and push up tests. Adherence to SEADiet was assessed with a semi-quantitative food frequency questionnaire (FFQ). The AIP was estimated as log (TG/HDL-C). Measures of pubertal stage and socioeconomic status were assessed. Linear regression showed a significant inverse association between MF (standardized β = -0.165; p \u3c 0.001), CRF (standardized β = -0.081; p \u3c 0.030) and SEADiet (standardized β = -0.081; p \u3c 0.045) with AIP, after adjustments for age, sex, pubertal stage and parental education. Furthermore, participants classified with an optimal as well as those with low adherence to a SEADiet but with LowMF/LowCRF had on average the highest AIP (F(7.482) = 3.270; p = 0.002). Moreover, optimal SEADiet with HighMF/HighCRF group showed the lowest AIP when compared with those with low adherence to a SEADiet with HighMF/HighCRF group (p = 0.03). AIP is inversely associated with MF, CRF and SEADiet. The low MF combined with a low CRF levels seems to overcome the potential healthy effect of having an optimal adherence to the SEADiet on AIP. However, an optimal adherence to SEADiet seems to improve the AIP in those adolescents with high fitness levels

In vivo and in vitro effects of RAD001 on bladder cancer

Objective: To evaluate the influence of Everolimus (RAD001) on chemically induced urothelial lesions in mice and its influence on in vitro human bladder cancer cell lines. Methods: ICR male mice were given N-butyl-N-(4-hydroxybutyl) nitrosamine in drinking water for a period of 12 weeks. Subsequently, RAD001 was administered via oral gavage, for 6 weeks. At the end of the experiment, all the animals were sacrificed and tumor development was determined by means of histopathologic evaluation; mammalian target of rapamycin (mTOR) expressivity was evaluated by immunohistochemistry. Three human bladder cancer cell lines (T24, HT1376, and 5637) were treated using a range of RAD001 concentrations. MTT assay, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), and flow cytometry were used to assess cell proliferation, apoptosis index, and cell cycle analysis, respectively. Immunoblotting analysis of 3 cell line extracts using mTOR and Akt antibodies was performed in order to study the expression of Akt and mTOR proteins and their phosphorylated forms. Results: The incidence of urothelial lesions in animals treated with RAD001 was similar to those animals not treated. RAD001 did not block T24 and HT1376 cell proliferation or induce apoptosis. A reduction in cell proliferation rate and therefore G0/G1 phase arrest, as well as a statistically significant induction of apoptosis (P 0.001), was only observed in the 5637 cell line. Conclusion: RAD001 seems not to have a significant effect on chemically induced murine bladder tumors. The effect of RAD001 on tumor proliferation and apoptosis was achieved only in superficial derived bladder cancer cell line, no effect was observed in invasive cell lines

Characterization of demolished concretes with three different strengths for recycling as coarse aggregate

This paper presents a physical characterization for the recycling into new concretes of three comminuted concretes: C16/20 (“ordinary concrete”), C50/60 (“high strength concrete”), and C70/85 (“very high strength concrete”). The top size of the crushed concretes was 19.1 mm and the size range was 4.75 to 19.1 mm. The characterization was carried out with coarse aggregate liberation, to be prepared and concentrated in a gravity concentration process. The density distribution of the coarse aggregate, cement paste, and sand was carried out in different size ranges (4.75/19.1 mm; 4.75/8.0 mm; 8.0/12.5 mm; and 12.5/19.1 mm) for the three concretes studied. The form factor of the samples, as well as the porosity determination of particles in different density ranges, are presented. The obtained results indicate that the coarse aggregate liberation was more intensive for the low resistance concrete (C16/20), but a reasonable coarse aggregate recovery is possible for all concretes

Seroprevalence of IgG and IgM anti-SARS-CoV-2 among voluntary blood donors in Rio de Janeiro, Brazil

Background: In Brazil, mathematical models for deriving estimates and projections of COVID-19 cases have been developed without data on asymptomatic SARS-CoV-2 infection. We estimated the seroprevalence of antibodies to SARS-CoV-2 among blood donors in the State of Rio de Janeiro. Methods: Data were collected on 2,857 blood donors from April 14 to 27, 2020. We report the crude prevalence of antibodies to SARS-CoV-2, the weighted prevalence by the total state population, and adjusted prevalence estimates for test sensitivity and specificity. To establish the correlates of SARS-CoV-2 prevalence, we used logistic regression models. The analysis included period and site of blood collection, sociodemographic characteristics, and place of residence. Results: The proportion of SARS-Cov-2 positive tests without any adjustment was 4.0% (95% CI 3.3-4.7%), and the weighted prevalence was 3.8% (95% CI 3.1-4.5%). Further adjustment by test sensitivity and specificity produced lower estimates, 3.6% (95% CI 2.7-4.4%) and 3.3% (95% CI 2.6-4.1%), respectively. The variable most significantly associated with the crude prevalence was the period of blood collection: the later the period, the higher the prevalence. Regarding socio-demographic characteristics, the younger the blood donors, the higher the prevalence, and the lower the educational level, the higher the odds of a positive SARS-Cov-2 antibody. Similar results were found for the weighted prevalence. Discussion: Although our findings resulted from a convenience sample, they match some basic premises: the increasing trend over time, since the epidemic curve in the state is still on the rise; the higher prevalence among the youngest who are more likely to circulate; and the higher prevalence among the less educated as they have more difficulties in following the social distancing recommendations. Despite the study limitations, it is possible to infer that protective levels of natural herd immunity to SARS-CoV-2 are far from being reached in Rio de Janeiro

Desenvolvimento vegetativo de cultivares de palma de óleo dos 14 aos 34 meses de idade em ecossistemas de Roraima.

Objetivou-se com este trabalho avaliar o desenvolvimento vegetativo de cultivares de palma de óleo Elaeis guineensis Jacq dos 14 aos 34 meses de idade no campo, em dois ecossistemas de Roraima. Foram conduzidos dois experimentos, sendo um em área de savana e outro em área de floresta alterada com a avaliação das cultivares BRS C-2528, BRS C-3701 e BRS C-2301, em deline amento experimental de blocos ao acaso com seis repetições. Foram realizadas 18 avaliações mensais, no período de agosto de 2008 a abril de 2010, quanto ao número de folhas emitidas, comprimento da folha 4 (cm) e circunferência do coleto (cm). Foram realizadas análises de variância individuais e conjuntas. Para a comparação das médias das características avaliadas foi utilizado o teste de Scott-Knott em nível de 5% de probabilidade. Pela comparação das médias das características avaliadas, nos dois ambientes, foi possível verificar que, aos 34 meses de idade, no ecossistema de floresta as plantas apresentaram maior número de folhas, maior comprimento da folha 4 e maior circunferência do coleto, diferindo significativamente, dos resultados obtidos em ecossistema de savana. Na área de floresta alterada, independente da cultivar avaliada, as plantas apresentaram mensalmente, 3,0 folhas emitidas, crescimento da folha 4 de 8,9 cm e circunferência do coleto de 9,6 cm, enquanto que, em savana, 2,5 folhas emitidas, comprimento da folha 4 de 7,5 cm e circunferência do coleto de 6,1cm. Conclui-se que no ambiente de floresta alterada, as cultivares apresentam desenvolvimento vegetativo superior ao obtido no ambiente de savana