554 research outputs found
Development of the Next Generation of Meteoroid and Orbital Debris Shields
The novel structure of metallic foams is of interest in the design of next-generation debris shields as it introduces physical mechanisms that are advantageous to hypervelocity impact shielding (e.g. increased fragmentation/melt/vaporization, energy dissipation, etc.). Preliminary investigations have shown improved shielding capability over traditional spacecraft primary structures. In this paper, the results of a current hypervelocity impact test program on metallic open-cell foam core sandwich panels are reported. A preliminary ballistic limit equation has been derived from the experimental results, and is presented in a form suitable for implementation in risk assessment software codes
The effects of an experimental programme to support students’ autonomy on the overt behaviours of physical education teachers
Although the benefits of autonomy supportive behaviours are now well established in the literature, very few studies have attempted to train teachers to offer a greater autonomy support to their students. In fact, none of these studies has been carried out in physical education (PE). The purpose of this study is to test the effects of an autonomy-supportive training on overt behaviours of teaching among PE teachers. The experimental group included two PE teachers who were first educated on the benefits of an autonomy supportive style and then followed an individualised guidance programme during the 8 lessons of a teaching cycle. Their behaviours were observed and rated along 3 categories (i.e., autonomy supportive, neutral and controlling) and were subsequently compared to those of three teachers who formed the control condition. The results showed that teachers in the experimental group used more autonomy supportive and neutral behaviours than those in the control group, but no difference emerged in relation to controlling behaviours. We discuss the implications for schools of our findings
Time to Intervene: A Continuous-Time Approach to Network Analysis and Centrality
Network analysis of ESM data has become popular in clinical psychology. In this approach, discrete-time (DT) vector autoregressive (VAR) models define the network structure with centrality measures used to identify intervention targets. However, VAR models suffer from time-interval dependency. Continuous Time (CT) models have been suggested as an alternative but require a conceptual shift, implying that DT-VAR parameters reflect total rather than direct effects. In this paper we propose and illustrate a CT network approach using CT-VAR models. We define a new network representation and develop centrality measures which inform intervention targeting. This methodology is illustrated with an ESM dataset
B2: Presence of Immunosuppressive Drugs affect Innate Immune Response and Monocyte Differentiation in Lung Transplant Patients
Lung transplant patients are administered Immunosuppressive Drugs (ISDs) to prevent transplant rejection, but this also puts them at constant risk of infection due to the decreased ability of the immune system to respond to subsequent infections by viruses, bacteria etc.
Purpose
This paper focuses on the effect of ISDs on the innate immune response. We are using different parts of viruses and bacteria and allowing them to represent the organism as a whole.
Methods
As representatives of the innate immune system, we are going to be testing monocyte, macrophage, and dendritic cell lineages. We are hypothesizing that the presence of ISDs dampens the immune system response to viruses/bacteria as well as that in the presence of ISDs, there is decreased differentiation of the monocytes into macrophages. We used PCR and Flow cytometry to help interpret the data. PCR allowed us to recognize innate immune transcriptional changes of the cells that were treated with ISDs in comparison to the control. We used the Flow Cytometer to test monocyte differentiation into macrophages.
Results
The results showed that there were certain innate immune genes that showed increase in expression, some showed decrease, while others showed no change in the presence of ISDs. It was also concluded that the presence of ISDs actually induced differentiation of Monocytes into Macrophages.
Conclusion
This information can be used to manipulate the immune systems of lung transplant patients to better respond to specific subsequent infections even in the presence of Immunosuppressive Drugs while still maintaining the integrity of the transplant
Landfast Sea Ice Conditions in the Canadian Arctic: 1983 – 2009
We used Canadian Ice Service (CIS) digital charts from 1983 to 2009 to create a climatology of landfast sea ice in the Canadian Arctic. The climatology characterized the spatial distribution and variability of landfast ice through an average annual cycle and identified the mean onset date, breakup date, and duration of landfast ice. Trends in date and duration of onset and breakup were calculated over the 26-year period on the basis of CIS regions and sub-regions. In several sub-regions— particularly in the Canadian Arctic Archipelago—we calculated significant trends towards later landfast ice onset or earlier breakup, or both. These later onset and earlier breakup dates translated into significant decreases in landfast ice duration for many areas of the Canadian Arctic. For communities located in the most affected areas, including Tuktoyaktuk, Kugluktuk, Cambridge Bay, Gjoa Haven, Arctic Bay, and Pond Inlet, this shorter landfast ice season is of significant social, cultural, and economic importance. Landfast sea-ice duration in the interior of the Northwest Passage has not undergone any statistically significant decrease over the time series.Nous nous sommes appuyés sur les cartes numériques du Service canadien des glaces (SCG) pour les années 1983 à 2009 afin de produire la climatologie de la glace de mer de l’Arctique canadien. La climatologie permet de caractériser la distribution spatiale et la variabilité de la glace de mer au moyen d’un cycle annuel moyen, et de déterminer la date moyenne du commencement, la date de la débâcle et la durée de la glace de mer. Les tendances en matière de dates et de durées relativement au commencement et à la débâcle ont été calculées sur la période de 26 ans en fonction des régions visées par le SCG et des sous-régions. Dans plusieurs sous-régions — plus particulièrement dans l’archipel Arctique canadien — nous avons calculé d’importantes tendances indiquant des dates de commencement plus tardives de la glace de mer ou des dates de débâcle plus hâtives, ou les deux. Ces dates plus hâtives et plus tardives se traduisent par la réduction considérable de la durée de la glace de mer en maints endroits de l’Arctique canadien. Pour les localités situées dans la plupart des régions touchées, dont Tuktoyaktuk, Kugluktuk, Cambridge Bay, Gjoa Haven, Arctic Bay et Pond Inlet, cette saison de glace de mer plus courte revêt une grande importance sur les plans social, culturel et économique. Du point de vue statistique, la durée de la glace de mer à l’intérieur du passage du Nord-Ouest n’a pas connu de réduction importante au cours de cette période
Uncertainty in below-ground carbon biomass for major land covers in Southeast Asia
10.1016/j.foreco.2013.09.042Forest Ecology and Management310915-926FECM
A Review of Controlling Motivational Strategies from a Self-Determination Theory Perspective: Implications for Sports Coaches
The aim of this paper is to present a preliminary taxonomy of six controlling strategies, primarily based on the parental and educational literatures, which we believe are employed by coaches in sport contexts. Research in the sport and physical education literature has primarily focused on coaches’ autonomysupportive behaviours. Surprisingly, there has been very little research on the use of controlling strategies. A brief overview of the research which delineates each proposed strategy is presented, as are examples of the potential manifestation of the behaviours associated with each strategy in the context of sports coaching. In line with self-determination theory (Deci & Ryan, 1985; Ryan & Deci, 2002), we propose that coach behaviours employed to pressure or control athletes have the potential to thwart athletes’ feelings of autonomy, competence,and relatedness, which, in turn, undermine athletes’ self-determined motivation and contribute to the development of controlled motives. When athletes feel pressured to behave in a certain way, a variety of negative consequences are expected to ensue which are to the detriment of the athletes’ well-being. The purpose of this paper is to raise awareness and interest in the darker side of sport participation and to offer suggestions for future research in this area
Are Wikis and Weblogs an Appropriate Approach to Foster Collaboration, Reflection and Students’ Motivation?
Measuring student teachers' basic psychological needs
In the Self-Determination Theory (SDT) basic psychological needs for relatedness, autonomy and competence are distinguished. Basic psychological need fulfilment is considered to be critical for human development and intrinsic motivation. In the Netherlands, the concept of basic psychological need fulfilment is introduced in the curricula of many teacher education institutes. In five teacher education institutes for primary school teachers, study coaches use a Dutch version of the Basic Psychological Needs Scale (BPNS), to collect data to be used in a discussion with student teachers about their intrinsic motivation for a specific part of the teacher education course. On the basis of the outcomes of this discussion, study coaches and student teachers derive consequences for day to day practice in their classrooms. The data were also used to establish whether the theoretical distinction between three basic psychological needs is found in this sample of student teachers in the Netherlands.
The results show that the constructs of relatedness, autonomy and competence are found and can be measured by using a 14-item five-point scale, partly based on the original BPNS, and partly on new items that focus on different sources of perceived need fulfilment, namely teacher education in general, the study coach and fellow students
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