The regime of climate-related disturbance and nutrient enrichment modulate macroalgal invasions in rockpools

Patterns of invasion by the seaweeds Grateloupia turuturu Yamada and Sargassum muticum (Yendo) Fensholt under crossed combinations of the regime (mean intensity and temporal variability) of climate-related mechanical disturbance and constant nutrient enrichment were experimentally examined in rockpools in north Portugal. The cover of both species was larger under high compared to low intensity of disturbance, but this effect was enhanced by events more heterogeneously distributed over a period of 19 months. The invasion by G. turuturu was also larger in enriched pools, but only when disturbance was applied at high intensity. The richness of native taxa was increased by high intensity events of disturbance evenly distributed over time and by low intensity events heterogeneously distributed, while no differences were documented for other treatments. Temporal variability of disturbance and nutrients interactively affected the total cover of native taxa and the availability of bare rock in different directions. Enriched conditions increased the space occupancy by natives and reduced substratum availability only when associated to heterogeneous events of disturbance. At the same time, relatively more variable disturbances caused a reduced cover by native taxa and an increased availability of free space, but only under natural nutrient levels. Present findings contribute to understand the conditions that would be more likely to facilitate the spread of G. turuturu and S. muticum under current and predicted scenarios of compounded environmental changes and in relation to traits of recipient systems that are considered relevant for the success of invasions, including the native richness and the degree of usage of resources, i.e. primarily space

O IMPACTO DOS FATORES INTRA E EXTRAESCOLARES PARA O FRACASSO ESCOLAR: DESMISTIFICANDO AS VISÕES PSICOLOGIZANTES

Existem muitas discussões sobre fatores relacionados ao fracasso escolar, inúmeras vezes relaciona-se aspectos sociais erroneamente como elementos determinantes do processo de aprendizagem. O presente artigo objetiva elencar os fatores extraescolares e intraescolares que interferem diretamente no fracasso escolar, bem como analisar historicamente a perpetuação desses fatores relevantes que associam a esta ideia como algo que impossibilita a capacidade do indivíduo de aprender, contribuindo para o sofrimento psicossocial do sujeito. O processo escolar é algo que não pode ser engessado, nesse cenário de diversidades, a instituição pode e deve criar situações que promovam mudanças. A Psicologia surge então, não para estruturar e construir novos conceitos sobre o fracasso escolar, mas com desafio de intervir nesta situação, sendo ela um dos instrumentos que apresenta novas possibilidades de atuação, a fim de reverter esse quadro e favorecer essa reestruturação. Para se obter as informações, foi realizada uma revisão bibliográfica em diversas plataformas como, Scielo, Pepsic, dados do INEP, teses de mestrado, bem como também a biblioteca do campus do Centro Universitário Tiradentes – UNIT, com intuito da disseminação de conhecimentos, para que se retire a concepção de fracasso escolar como problema individual, bem como a importância de intervenções preventivas

Impacts of climate change on plant diseases – opinions and trends

There has been a remarkable scientific output on the topic of how climate change is likely to affect plant diseases in the coming decades. This review addresses the need for review of this burgeoning literature by summarizing opinions of previous reviews and trends in recent studies on the impacts of climate change on plant health. Sudden Oak Death is used as an introductory case study: Californian forests could become even more susceptible to this emerging plant disease, if spring precipitations will be accompanied by warmer temperatures, although climate shifts may also affect the current synchronicity between host cambium activity and pathogen colonization rate. A summary of observed and predicted climate changes, as well as of direct effects of climate change on pathosystems, is provided. Prediction and management of climate change effects on plant health are complicated by indirect effects and the interactions with global change drivers. Uncertainty in models of plant disease development under climate change calls for a diversity of management strategies, from more participatory approaches to interdisciplinary science. Involvement of stakeholders and scientists from outside plant pathology shows the importance of trade-offs, for example in the land-sharing vs. sparing debate. Further research is needed on climate change and plant health in mountain, boreal, Mediterranean and tropical regions, with multiple climate change factors and scenarios (including our responses to it, e.g. the assisted migration of plants), in relation to endophytes, viruses and mycorrhiza, using long-term and large-scale datasets and considering various plant disease control methods

Muscle protein metabolism in neonatal alloxan-administered rats: effects of continuous and intermittent swimming training

<p>Abstract</p> <p>Background</p> <p>This study aimed to examine the effects of intermittent and continuous swimming training on muscle protein metabolism in neonatal alloxan-administered rats.</p> <p>Methods</p> <p>Wistar rats were used and divided into six groups: sedentary alloxan (SA), sedentary control (SC), continuous trained alloxan (CA), intermittent trained alloxan (IA), continuous trained control (CC) and intermittent trained control (IC). Alloxan (250 mg/kg body weight) was injected into newborn rats at 6 days of age. The continuous training protocol consisted of 12 weeks of swimming training in individual cylinder tanks while supporting a load that was 5% of body weight; uninterrupted swimming for 1 h/day, five days a week. The intermittent training protocol consisted of 12 weeks of swimming training in individual cylinder tanks while supporting a load that was 15% of body weight; 30 s of activity interrupted by 30 s of rest for a total of 20 min/day, five days a week.</p> <p>Results</p> <p>At 28 days, the alloxan animals displayed higher glycemia after glucose overload than the control animals. No differences in insulinemia among the groups were detected. At 120 days, no differences in serum albumin and total protein among the groups were observed. Compared to the other groups, DNA concentrations were higher in the alloxan animals that were subjected to continuous training, whereas the DNA/protein ratio was higher in the alloxan animals that were subjected to intermittent training.</p> <p>Conclusion</p> <p>It was concluded that continuous and intermittent training sessions were effective in altering muscle growth by hyperplasia and hypertrophy, respectively, in alloxan-administered animals.</p

Climate Change and the Future of California's Endemic Flora

The flora of California, a global biodiversity hotspot, includes 2387 endemic plant taxa. With anticipated climate change, we project that up to 66% will experience >80% reductions in range size within a century. These results are comparable with other studies of fewer species or just samples of a region's endemics. Projected reductions depend on the magnitude of future emissions and on the ability of species to disperse from their current locations. California's varied terrain could cause species to move in very different directions, breaking up present-day floras. However, our projections also identify regions where species undergoing severe range reductions may persist. Protecting these potential future refugia and facilitating species dispersal will be essential to maintain biodiversity in the face of climate change