999 resultados para Tieck, Ludwig, 1773-1853,


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: Immunity plays an important role in controlling human papillomavirus (HPV) infection and associated lesions. Unlike infections caused by other viruses, natural HPV infection does not always result in a protective antibody response. Therefore, HPV antibodies are also considered markers of cumulative exposure. The aim of this study was to identify determinants of HPV16 seroreactivity at enrollment among women from the Ludwig-McGill cohort, a natural history study of HPV infection and risk of cervical neoplasia.Methods: HPV16 serology was assessed by ELISA for L1 and L2 capsid antigens, while HPV typing and viral load measurements were performed by PCR-based methods. The associations were analyzed by unconditional logistic regression.Results: Of 2049 subjects, 425 (20.7%) were strongly seropositive for HPV16. In multivariate analysis, seroreactivity was positively correlated with age, lifetime number of sexual partners, frequency of sex, and HPV16 viral load, and negatively associated with duration of smoking.Conclusions: HPV16 seroreactivity is determined by factors that reflect viral exposure.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Cientifico e Tecnológico (CNPq)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper is part of a broader investigation on Epistemology of Biology carried out by a group of researchers from Cascavel/PR. It involves studies and research about biological thought on subjects such as the growing of the concepts of gene, genotype and phenotype. The aim of this research was to gather the undergraduate students of Biological Sciences’ views about the role played by the inclusion of a historical episode in the study group as a trigger for epistemological discussions and didactic reflections. Firstly, the students received Johannsen’s article “The genotype conception of heredity”, published in 1911 in the journal The American Naturalist, in which he proposed the concepts of genotype and phenotype, among other ones. After, there was a discussion held by group about the concepts proposed in the article taking into account the epistemological, historical and didactic aspects. Data collection occurred through the recording of the group discussions and individual interviews. The results suggest that the inclusion of this historical episode, enabled the participants to develop critical thinking through collective reflection on the meaning of biological knowledge in different contexts.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper aims an epistemologically analysis of the attempt of James Prescott Joule to replace the steam engine by the electric one. In this historical analysis, we use the epistemological categories: style of thinking, collective thinking, intercollective circulation of ideas and practices,Joule and other technicians in Machester received in that time financial incentives from governments and industry to replace the steam engine by the electric one, since it was in Manchester a culture of the technique of the accuracy and precision in which Joule was immersed, which allowed us to initially identify the styles of techniques thinking and experimental efficiency. However, Joule could not replace the steam engine by the electric; and the awareness of the problems faced by him, in the attempt to make such a substitution, led him to seek, through an intercollective circulation of ideas and practices, such as the studies of Faraday and Jacobi, a change of direction in his researches. According to our analysis, what happened was a change of style from a technical to a scientific thinking. In this sense, Joule began to investigate issues of a scientific nature, as the Joule’s effect and the mechanical equivalent of heat, which contributed significantly to the establishment of the principle of conservation of energy. We present here the contributions of this epistemological analysis to the discussion of questions of the nature of science in the basic education and for the training of physics teachers.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The sugar cane plantation expands its borders each year, throughout the national territory. Thus, increases the amount of biomass that will to be exploited by man in sugar and alcohol produce and also by other organisms, which will have food in abundance. The growth of mechanized harvesting, with the consequent decrease in burning of straw and the expansion of the sucroalcooleiro sector are causing changes into entomofauna in certain areas or regions of sugar cane plantation. One of the new threats to the sugar cane plantations in southcentral region, causing uncertainty and concern to farmers, is the giant worm, Telchin licus, known in Brazil since 1927, in the Northeast of Brazil, is considered a major pest of cane sugar. In 2007 it was first recorded in the state of São Paulo, which accounts for 60% of the country's crops. Whereas until then there is not much information about their management and control, the aim of this review is to gather information on the basis for its control within the context of Integrated Pest Management of cane sugar.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The reproductive biology and population dynamics of the cirolanid isopod Excirolana armata (Dana, 1853) were analysed through monthly samples from December 2003 to November 2005 on Una beach, Sao Paulo state (24 degrees S), in Southeastern Brazil. Sampling was performed along three transects established from the base of foredunes to the waterline. On Una beach, E. armata showed continuous reproduction with higher abundances of ovigerous females in winter and spring (July-November) with a higher peak of juveniles in spring (November 2004). The fecundity ranged from 2 to 18 eggs/embryos per female, depending on the female length. The incubation period was estimated as 2 months. The life span of males and females was nearly 1 year. The short life span and the high energetic expenditure inherent to reproduction with maternal care, probably kept females from producing more than one brood in their lifetime. When comparing the population of E. armata on Una beach (24 degrees S) with populations in Southern Brazil (32 degrees S), Uruguay (34 degrees S) and Argentina (36 degrees S), it was verified that several biological population traits (length of the smallest juvenile, length of the largest individual, length of the smallest and largest ovigerous females, range of fecundity and life span) tended to increase at higher latitudes, whereas other traits (instantaneous rate of mortality and the curvature parameter of von Bertalanffy growth function) tended to decrease. However, comparing E. armata on Una beach (24 degrees S) with a population situated at a close latitude (25 degrees S), unexpected differences in relation to population structure and to growth demonstrated and reinforced the importance of density-dependent factors over life history traits of E. armata on dissipative beaches.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The somatic and gonad productions of the cirolanid isopod Excirolana armata were analyzed by taking monthly samples from December 2003 to November 2005 on Una beach, So Paulo state (24A degrees S), southeastern Brazil. Sampling was performed along three fixed transects established from the base of the foredunes to the waterline. Weight-specific growth rate was used to estimate the E. armata somatic production for 2004 and 2005, separately. The gonad production was estimated based on the monthly reproductive potential (mean number of eggs/embryos per female x monthly abundance of ovigerous females with near-release broods) for 2004. The annual somatic production of E. armata population varied from 15.57 to 17.25 g AFDW m(-1) year(-1) and the somatic production/biomass ratio (P (s)/B) from 3.55 to 3.14 year(-1) for 2004 and 2005, respectively. The P (s)/B ratios were higher for males (4.02 and 3.19 year(-1) for 2004 and 2005) than for females (3.10 year(-1) for both years). The annual gonad production (P (g) = 1.07 g AFDW m(-1) year(-1)) contributed about 15 and 6% to the total production (P (s) + P (g)) of females and the population, respectively. The proportion of gonad to somatic production of females (P (g)/P (s)) increased with individual size (ca 90% in the 7.5 mm size class), and the annual weight-specific gonad production (P (g)/B ratio) was estimated to 0.24 year(-1). The high P (s)/B ratios estimated for E. armata derive from the fast growth of individuals and show the importance of this population to the energy flow on Una beach ecosystem. However, the low percentage of juveniles verified in this population and in other studies of populations of the genus Excirolana is discussed as an important source of underestimation of P (s)/B ratio.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The final instar larva of Mnesarete pudica is described and illustrated based on reared specimens collected in Brazil. This species can be distinguished from others by presenting: a) five palpal and three premental setae; b) no posterodorsal hooks on abdominal segments; c) lateral spines only in S9-10. M. pudica is compared to other South American calopterygids and biological notes are presented.

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador: