3 resultados para To-face Consultations

em Repositório Institucional da Universidade de Aveiro - Portugal


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Extreme abiotic factors, such drought combined with heat waves and/or high UVB radiation are predicted to become more frequent in the future. The impact on plant production of these challenges on multipurpose Moringa oleifera L. remains unclear. A susceptibility of this species may lead to increase poverty in endangered regions. M. oleifera is a woody species native from sub-Himalaya regions under high climate stress pressure. The interest on this species is emerging due to its several medicinal properties and its nutritional value. Agropharmaceutical industry is interest in this species too. To understand the impact of increased climate factors, young (2 months old) plants of this species were exposed to water deficit (WD) and UVB (alone or combined). WD and WD+UVB imposition consists of unwater for 4 days. After 1 day withholding water, UVB and WD+UVB were irradiated with 26.3 kJ m-2 distributed per 3 days. Immediately after treatment exposition (1 day) and after 10 days, plant water status, growth, carbon metabolism and oxidative stress were measured. Overall no significant differences were observed in WD, regarding the parameters analysed, except on gas exchanges, MDA and phenols. The plants exposed to UVB showed, in general, more severe effects, as higher pigment content, MDA and membrane permeability, while no changes were observed in the total antioxidant activity. Plants exposed to UVB+WD, despite changes observed, the impact was lower than the one observed in UVB exposed plants, meaning that a protective/adaptive mechanism was developed in the plants under combined stressors. On the other hand, in all treatments the net CO2 assimilation rate decreased. Results suggest that M. oleifera has some tolerance to WD and UVB, and that develops mechanism of adaptation to these two types of stress that often arise in combination under a climate change scenario.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

Estuaries are highly dynamic systems which may be modified in a climate change context. These changes can affect the biogeochemical cycles. Among the major impacts of climate change, the increasing rainfall events and sea level rise can be considered. This study aims to research the impact of those events in biogeochemical dynamics in the Tagus Estuary, which is the largest and most important estuary along the Portuguese coast. In this context a 2D biophysical model (MOHID) was implemented, validated and explored, through comparison with in-situ data. In order to study the impact of extreme rainfall events, which can be characterized by an high increase in freshwater inflow, three scenarios were set by changing the inputs from the main tributaries, Tagus and Sorraia Rivers. A realistic scenario considering one day of Tagus and Sorraia River extreme discharge, a scenario considering one day of single extreme discharge of the Tagus River and finally one considering the extreme runoff just from Sorraia River. For the mean sea level rise, two scenarios were also established. The first with the actual mean sea level value and the second considering an increase of 0.42 m. For the extreme rainfall events simulations, the results suggest that the biogeochemical characteristics of the Tagus Estuary are mainly influenced by Tagus River discharge. For sea level rise scenario, the results suggest a dilution in nutrient concentrations and an increase in Chl-a in specific areas.For both scenarios, the suggested increase in Chl-a concentration for specific estuarine areas, under the tested scenarios, can lead to events that promote an abnormal growth of phytoplankton (blooms) causing the water quality to drop and the estuary to face severe quality issues risking all the activities that depend on it.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

Within the business context, communication and interaction tends to be considerably rooted in the use of English (as lingua franca), as well as in ICT use. Thus, professionals have to be able to speak the English language, resorting to specific, internationally recognised terminology and be proficient in the use of manifold ICT tools. In fact, the tendency is for the great majority of higher education (HE) students to own mobile devices (laptops, smartphones and/or tablets) and use them to access information and communicate/interact with content and other people. Bearing this in mind, a teaching and learning strategy was designed, in which m-learning (i.e. learning in which the delivery platform is a mobile device) was used to approach Business English Terminology (BET). The strategy was labelled as ‘BET on Top Hat’, once the selected application was Top Hat (https://tophat.com/) and the idea was for students to face it as if it were a game/challenge. In this scenario, the main goals of this exploratory study were to find evidence as to: i) the utility of m-learning activities for learning BET and ii) if and how m-learning activities can generate intrinsic motivation in students to learn BET. Participants (n=23) were enrolled in English II, a curricular unit of the 1st cycle degree in Retail Management offered at Águeda School of Technology and Management – University of Aveiro (2014/15 edition). The data gathered included the students’ results in quizzes and their answers to a short final evaluation questionnaire regarding their experience with BET on Top Hat. Consequently, data were treated and analysed resorting to descriptive statistical analysis, and, when considered pertinent, the teacher’s observation notes were also considered. The results unveil that, on the one hand, the strategy had a clear positive impact on the students’ intrinsic motivation and, on the other hand, the students’ performance as to BET use tended to improve over time.