931 resultados para Anthropology, Cultural|History, Black|Sociology, Social Structure and Development


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Two important challenges that teachers are currently facing are the sharing and the collaborative authoring of their learning design solutions, such as didactical units and learning materials. On the one hand, there are tools that can be used for the creation of design solutions and only some of them facilitate the co-edition. However, they do not incorporate mechanisms that support the sharing of the designs between teachers. On the other hand, there are tools that serve as repositories of educational resources but they do not enable the authoring of the designs. In this paper we present LdShake, a web tool whose novelty is focused on the combined support for the social sharing and co-edition of learning design solutions within communities of teachers. Teachers can create and share learning designs with other teachers using different access rights so that they can read, comment or co-edit the designs. Therefore, each design solution is associated to a group of teachers able to work on its definition, and another group that can only see the design. The tool is generic in that it allows the creation of designs based on any pedagogical approach. However, it can be particularized in instances providing pre-formatted designs structured according to a specific didactic method (such as Problem-Based Learning, PBL). A particularized LdShake instance has been used in the context of Human Biology studies where teams of teachers are required to work together in the design of PBL solutions. A controlled user study, that compares the use of a generic LdShake and a Moodle system, configured to enable the creation and sharing of designs, has been also carried out. The combined results of the real and controlled studies show that the social structure, and the commenting, co-edition and publishing features of LdShake provide a useful, effective and usable approach for facilitating teachers' teamwork.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

PHO1 has been recently identified as a protein involved in the loading of inorganic phosphate into the xylem of roots in Arabidopsis. The genome of Arabidopsis contains 11 members of the PHO1 gene family. The cDNAs of all PHO1 homologs have been cloned and sequenced. All proteins have the same topology and harbor a SPX tripartite domain in the N-terminal hydrophilic portion and an EXS domain in the C-terminal hydrophobic portion. The SPX and EXS domains have been identified in yeast (Saccharomyces cerevisiae) proteins involved in either phosphate transport or sensing or in sorting proteins to endomembranes. The Arabidopsis genome contains additional proteins of unknown function containing either a SPX or an EXS domain. Phylogenetic analysis indicated that the PHO1 family is subdivided into at least three clusters. Reverse transcription-PCR revealed a broad pattern of expression in leaves, roots, stems, and flowers for most genes, although two genes are expressed exclusively in flowers. Analysis of the activity of the promoter of all PHO1 homologs using promoter-beta-glucuronidase fusions revealed a predominant expression in the vascular tissues of roots, leaves, stems, or flowers. beta-Glucuronidase expression is also detected for several promoters in nonvascular tissue, including hydathodes, trichomes, root tip, root cortical/epidermal cells, and pollen grains. The expression pattern of PHO1 homologs indicates a likely role of the PHO1 proteins not only in the transfer of phosphate to the vascular cylinder of various tissues but also in the acquisition of phosphate into cells, such as pollen or root epidermal/cortical cells.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This article challenges the notion of economic rationality as a criterion for explaining ethnic boundary maintenance. It offers an ethnographic analysis of inter-ethnic relations in the context of games (cockfights and game-fishing contests) in the island of Raiatea (French Polynesia). Although all players engage in the same basic gambling practices, money is differentially scaled and mobilized by the Tahitian and Chinese participants. Building on recent pragmatic approaches to rationality, it is shown that the players' rationalities differ not from the point of view of economic maximization, but only in so far as they participate in social relations at different scales.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

We review the different meanings that researchers have given to theconcept of social capital, differentiate four types – bridging, bonding,linking, and overheads –, and discuss their different functions as public,club, and common goods.For each form of social capital we distinguish its productivity (acollective characteristic) from the factors that account for individual’sdifferential access to its returns, and propose alternative ways formeasuring each.We show the utility of our theoretical and measuring approach byanalyzing the impact of the each form of social capital on 15 year-oldstudents’ cognitive attainment across OECD countries, using 2006 PISAdata.The results show that students’ cognitive attainments are a direct functionof the richness or productivity of each form of social capital and ofstudents’ degree of access to each.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The demographic shift underway in Southern Europe requires a revision of some of the fundamental principles of the traditional welfare state. We analyze the evolution of several aspects of welfare and social expenditure over the last two decades. We find that in the context of the present demographic changes and real estate boom current social and pension policy leads to a new distribution of benefits and burdens which is highly intergenerationally unequal. We argue for a revised definition of public policy based on Musgrave's proposition as a possible rule for an intergenerationally fair distribution.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Indirect evidence from trapping suggests that Crocidura russula is less solitary and territorial than other shrews. To study the social organization and mating system, free-ranging adult and juvenile C. russula were tracked simultaneously throughout the year using a radioactive tracking technique. Coincident rest, coincident activity and home range overlap were measured. During winter, all individuals used the same communal nest and spent on average 84% of their total rest in coincident rest. This led to a large home range overlap (52% on average). Coincident activity was low (2% on average). At the onset of the reproductive season the females became, territorial and shared their nest with only one male. During pair formation, coincident activity and home range overlap were significantly greater between than within sexes. The social organization of C. russula appeared to be strongly influenced by season and differed in this respect from the other species in the genus Sorex which are territorial throughout the year.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The objective of this study was to find out the relationship between students’ perception of Social Studies and their academic performance in the subject in Colleges of Education in Kaduna State. The respondents of the study comprised NCE 2 and NCE 3 students of Social Studies at the Federal College of Education in Zaria and the Kaduna State College of Education in Gidan Waya. The data for the study was collected using a questionnaire with reliability coefficient of 0.87. The Pearson’s Product Moment Correlation Coefficient was used to test the hypotheses formulated for the study. The hypotheses were tested at 0.05 level of significance with df = 232. The findings were as follows: 1. The Social Studies students in colleges of education in Kaduna State do not record high academic performance in the subject. 2. Students’ perception of the Social Studies curriculum does affect their academic performance in the subject 3. Students’ perception of relevance of Social Studies education has no bearing on their academic performance in the subject. 4. Students’ perception of public attitude towards Social Studies has no impact on their academic performance in the subject. 5. Students’ general perception of Social Studies does not affect their academic performance in the subject. Based on these findings the following recommendations were proffered for Social Studies researchers and policy makers. a. There is need for further research in order to determine the actual cause of students’ failure to display high performance in Social Studies. b. The NCE Social Studies curriculum should be reviewed in terms of volume and difficulty.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

AIMS: The aim of this study was to investigate the heritability as well as genetic and environmental correlations of left ventricular (LV) structural and functional traits in complex pedigrees of a Caucasian population. METHODS AND RESULTS: We randomly recruited 459 white European subjects from 52 families (50% women; mean age 45 years). LV structure was measured by M-mode and 2D echocardiography and LV function was measured by conventional Doppler and tissue Doppler imaging (TDI). Other measurements included blood pressure, anthropometric, and biochemical measurements. We estimated the heritability of LV traits while adjusting for covariables, including sex, age, body height and weight, systolic and diastolic blood pressures, and heart rate. With full adjustment, heritability of LV mass was 0.23 (P= 0.025). The TDI-derived mitral annular velocities Ea and Aa showed moderate heritability (h(2)= 0.36 and 0.53, respectively), whereas the mitral inflow A peak had weak heritability (h(2) = 0.25) and the E peak was not heritable (h(2) = 0.11). We partitioned the total phenotypic correlation when it reached significance, into a genetic and an environmental component. The genetic correlations were 0.61 between the E and Ea peaks and 0.90 between the A and Aa peaks. CONCLUSION: Our study demonstrated moderate heritability for LV mass as well as the mitral annular Ea and Aa peaks. We also found significant genetic correlations between the E and Ea peaks and between the A and Aa peaks. Our current findings support the ongoing research to map and detect genetic variants that contribute to the variation in LV mass and other LV structural and functional phenotypes.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Many political economic theories use and emphasize the process of votingin their explanation of the growth of Social Security, governmentspending, and other public policies. But is there an empirical connectionbetween democracy and Social Security program size or design? Using somenew international data sets to produce both country-panel econometricestimates as well as case studies of South American and southern Europeancountries, we find that Social Security policy varies according toeconomic and demographic factors, but that very different politicalhistories can result in the same Social Security policy. We find littlepartial effect of democracy on the size of Social Security budgets, onhow those budgets are allocated, or how economic and demographic factorsaffect Social Security. If there is any observed difference, democraciesspend a little less of their GDP on Social Security, grow their budgetsa bit more slowly, and cap their payroll tax more often, than doeconomically and demographically similar nondemocracies. Democracies andnondemocracies are equally likely to have benefit formulas inducingretirement and, conditional on GDP per capita, equally likely to induceretirement with a retirement test vs. an earnings test.