Seed Cell Wall Storage Polysaccharides: Models to Understand Cell Wall Biosynthesis and Degradation

Cell wall storage polysaccharides (CWSPs) are found as the principal storage compounds in seeds of many taxonomically important groups of plants. These groups developed extremely efficient biochemical mechanisms to disassemble cell walls and use the products of hydrolysis for growth. To accumulate these storage polymers, developing seeds also contain relatively high activities of noncellulosic polysaccharide synthases and thus are interesting models to seek the discovery of genes and enzymes related to polysaccharide biosynthesis. CWSP systems offer opportunities to understand phenomena ranging from polysaccharide deposition during seed maturation to the control of source-sink relationship in developing seedlings. By studying polysaccharide biosynthesis and degradation and the consequences for cell and physiological behavior, we can use these models to develop future biotechnological applications.

Pharmacological properties of purinergic receptors and their effects on proliferation and induction of neuronal differentiation of P19 embryonal carcinoma cells

We have used P19 embryonal carcinoma cells as in vitro model for early neurogenesis to study ionotropic P2X and metabotropic P2Y receptor-induced Ca2+ transients and their participation in induction of proliferation and differentiation. In embryonic P19 cells, P2Y(1), P2Y(2) and P2X(4) receptors or P2X-heteromultimers with similar P2X4 pharmacology were responsible for ATP and ATP analogue-induced Ca2+ transients. In neuronal-differentiated cells, P2Y(2), P2Y(6), P2X(2) and possibly P2X(2)/P2X(6) heteromeric receptors were the major mediators of the elevations in intracellular free calcium concentration [Ca2+](i). We have collected evidence for the involvement of metabotropic purinergic receptors in proliferation induction of undifferentiated and neural progenitor cells by using a BrdU-incorporation assay. ATP-, UTP-, ADP-, 2-MeS-ATP- and ADP-beta S-induced proliferation in P19 cells was mediated by P2Y, and P2Y2 receptors as judged from pharmacological profiles of receptor responses. ATP-provoked acceleration of neuronal differentiation, determined by analysis of nestin and neuron-specific enolase gene and protein expression, also resulted from P2Y, and P2Y2 receptor activation. Proliferation- and differentiation-induction involved the activation of inositol-trisphosphate sensitive intracellular Ca2+ stores. (C) 2008 ISDN. Published by Elsevier Ltd. All rights reserved.

Deadly Desire : A Psychoanalytical Reading of Desire and Death in the Poetry of Dylan Thomas

Dylan Thomas' work is often explored in light of the poet himself, and he has been referred to as modernism's l'enfant terrible or even described as a late romanticist. The aim in this essay is to explore the poetry without regard to his personal life as well as highlight previously ignored oedipal elements in said poetry. The main goal is to assert Thomas' place amongst the modernist literati, of which most were heavily influenced by Freud, as well as to be an acknowledgement of his work without considering his biography.

Development, capabilities and technology : an evaluative framework

In this paper we present a framework to be used for evaluation of Information and Communication Technology for Development (ICT4D) projects. The framework is based on Sen´s notion of development as freedom where human capabilities and functionings are seen as key aspects to development. Sen´s capability approach presents an alternative way of seeing and evaluating development (alternative to more traditional ways of measuring development). The approach is based on expanding freedoms, or eliminating unfreedoms, for people so that they can live a life that they have reason to value. Even though Sen is referenced a lot in ICT4D literature the analysis rarely goes further then stating that Sen presents an alternative to traditional ways of development. Reasons can be that the capability approach does not specifically mention technology, in addition to the lack of guidelines presented by Sen on how to use the framework. The aim of this paper is to operationalize the evaluation process and to include a clear role for technology in Sen´s capability framework. The framework is validated with a case on distance education from Bangladesh. 

Risk of recurrent stroke and death after first stroke in long-distance ski race participants

Background: Physical activity is of benefit for primary prevention of cardiovascular diseases, but it appears to increase the risk for atrial fibrillation. We aimed to study a cohort of patients following a first stroke in individuals with previous high physical activity, compare them to the general population with respect to recurrent stroke and death, and relate these to atrial fibrillation. Methods and results: From the participants of the Vasaloppet, the world's largest ski-race, and matched individuals from the general population (n=708 604), we identified 5964 patients hospitalized with a first-time stroke between 1994 and 2010. Individuals with severe diseases were excluded. One half percent of skiers and 1% of nonskiers were hospitalized due to stroke. The incidence rate was 8.3 per 100 person-years among skiers and 11.1 among nonskiers. The hazard ratio (HR) for recurrent stroke or death between the 2 groups was 0.76 (95% CI 0.67 to 0.86). The result was consistent in subgroups. The HR for death was 0.66 (95% CI 0.56 to 0.78) and for recurrent stroke 0.82 (95% CI 0.70 to 0.96). After adjustment for smoking and socioeconomic factors, the HR for death was consistent at 0.70 (95% CI 0.56 to 0.87) while the HR for recurrent stroke was not statistically significant. Outcomes for skiers with atrial fibrillation tended to show a lower risk than for nonskiers. Conclusions: This large cohort study supports the hypothesis that patients with a stroke and with prior regular physical activity have a lower risk of death, while their risk for recurrent stroke is similar to that of nonskiers. The skiers had a higher incidence of atrial fibrillation, but still no increased risk of recurring stroke.

Life and Death: The Religious, Philosophical and Moral Dilemmas in Medicine

Religious beliefs often play a major role in the decisions that are made in the home and the hospital concerning issues at the beginning and end of life. Only recently, however, due to rapidly advancing medical technology, have religious, moral, and philosophical beliefs taken such a controversial role. One of the major questions that has arisen from these various controversies is whether or not we have the right to posses control over the biological functions of our bodies. The answer is a difficult one, and it may be one that cannot be answered, but the attempt at an answer is what is at the heart of medical ethics.

Exchange rate policies, patterns of specialization and economic development: theory and evidence in developing countries

The objectives of this paper are twofold. First, it intends to provide theoretical elements to analyze the relation between real exchange rates and economic development. Our main hypothesis is very much in line with the Dutch disease literature, and states that competitive currencies contribute to the existence and maintenance of the anufacturing sector in the economy. This, in turn, brings about higher growth rates in the long run, given the existence of increasing returns in the industrial sector, and its importance in generating echnological change and increasing productivity in the overall economy. The second objective of this paper is empirical. It intends to analyze examples of successful exchange rate policies, such as Chile and Indonesia in the eighties, as a benchmark for comparison with countries where currency overvaluation has taken place, such as Brazil. In the latter case, the local currency is being inflated by large capital inflows, due to high domestic interest rates and to a boom in demand and prices of commodities in the international markets. It will be argued that the industrial sector bears most of the burden when the currency appreciates, and that Brazil risks at deindustrialization if there are no changes in the exchange rate regime

Development, progress and economic growth

Progress was an idea of the 18th century; development, a project of the 20th century that continues into the 21st century. Progress was associated with the advance of reason, development with the fulfillment of the five political objectives that modern societies set for themselves: security, freedom, economic well-being, social justice and protection of the environment. Today we can view progress and development as equivalent. Both were products of the capitalist revolution, and of the economic development that began with it. Economic development or growth, in its turn, is the process of capital accumulation with the incorporation of technical progress that, mainly through productive sophistication and the increase of the value of labor, increases wages and improves standards of living. The five objectives that define development, as well as the three social instances existing in society change in an interdependent way.