391 research outputs found
Dynamic and tribological analysis of a toroidal CVT
The continuously variable transmission investigated in this paper works with contacts in the elastohydrodynamic regime of lubrication, thus the tangential forces are transmitted between elements through the shearing the lubricant film. The behavior of the lubricant film when subjected to shear depends of the nature of the lubricant and the relative motion between the contacting surfaces. In this paper a non-Newtonian behavior is assumed for the lubricant while the relative motion is determined for every point on the contact area by kinematic methods. The net tractive force in the sliding direction, and the spin torque are evaluated and from these the power losses in the contacts are calculated. The dynamic behavior of the device is evaluated taking into account the rheological behavior of the lubricant
Crossover in thermal transport mechanism in nanocrystalline silicon
Using vibrational mode analysis, we demonstrate that lattice vibrations in small grain (less than or similar to 3 nm) structurally inhomogeneous nanocrystalline silicon are almost identical to those in homogeneous amorphous structures with the majority of the vibrations delocalized and unpolarized. As a consequence the principal thermal conductivity mechanism in such a nanocrystalline material is the same as in the amorphous material. With increasing grain size the ability of vibrations to homogenize over the nanocrystalline structure is gradually lost and the phonon spectrum becomes progressively more like that of a crystalline material; this is reflected in a crossover in the mechanism of thermal transport
Performance of bias corrected MPEG rainfall estimate for rainfall-runoff simulation in the upper Blue Nile Basin, Ethiopia
In many developing countries and remote areas of important ecosystems, good quality precipitation data are neither available nor readily accessible. Satellite observations and processing algorithms are being extensively used to produce satellite rainfall products (SREs). Nevertheless, these products are prone to systematic errors and need extensive validation before to be usable for streamflow simulations. In this study, we investigated and corrected the bias of Multi-Sensor Precipitation EstimateâGeostationary (MPEG) data. The corrected MPEG dataset was used as input to a semi-distributed hydrological model Hydrologiska ByrĂ„ns Vattenbalansavdelning (HBV) for simulation of discharge of the Gilgel Abay and Gumara watersheds in the Upper Blue Nile basin, Ethiopia. The result indicated that the MPEG satellite rainfall captured 81% and 78% of the gauged rainfall variability with a consistent bias of underestimating the gauged rainfall by 60%. A linear bias correction applied significantly reduced the bias while maintaining the coefficient of correlation. The simulated flow using bias corrected MPEG SRE resulted in a simulated flow comparable to the gauge rainfall for both watersheds. The study indicated the potential of MPEG SRE in water budget studies after applying a linear bias correction
How PETE comes to matter in the performance of social justice education
Background: For over four decades there have been calls for physical education (PE) and physical education teacher education (PETE) to address social inequality and foster social justice. Yet, as numerous studies demonstrate, attempts to educate for social justice in PETE are infrequent and rarely comprehensive. This raises the question why it appears to be possible in some situations but not others, and for some students and not others. Â Â
Purpose: The purpose of this paper is to examine the multiple socio-political networks or assemblages in which PETE is embedded and explore how these shape the possibilities for students to engage with the concept of social justice and sociocultural issues when learning to teach PE. Two research questions guided this study: How does an orientation for social justice education within education policy affect the standards for enacting PETE programs? How is social justice education encouraged within PETE programs?
Methodology: Methodology: Drawing from a broader study of over 70 key personnel in more than 40 PETE programs, we examined how faculty in PETE understand their professional world, identify their subjective meanings of their experiences, and address sociocultural issues (SCI) and social justice education (SJE) within PETE. Data sources included an initial survey, a semi-structured interview, and program artifacts. We analyze the ways that SJE/SCI was represented in three national settings (England, the United States, and New Zealand) and identified common themes.
Results: Â Examination of each national setting reveals ways that SJE and SCI were enabled and constrained across the national, programmatic, and individual level in each of the countries. The coherence of explicit National policy and curricula, PETE program philosophies, and the presence of multiple individual interests in social justice served to reify a sociocultural agenda. Conversely possibilities were nullified by narrow or general National Standards, programs that failed to acknowledge sociocultural interests, and the absence of a critical mass of actors with a socio-critical orientation. These differences in assemblage culminated in variations in curriculum time that served to restrict or enable the breadth, frequency, and consistency of the messages surrounding SCI in PETE
Conclusion: These findings highlight the importance of acknowledging socio-political networks where PETE operates. The agency of PETEs to enact pedagogies that foreground sociocultural interests is contingent on congruity of the networks. The authors caution that although the âperfect stormâ of conditions have a profound influence of the possibility of transformational learning of SCI in PETE, this arrangement is always temporary, fluid, and subject to changes in any of the three network levels. Additionally, the success of PETE in enabling graduating PE teachers to recognize the inequities that may be reinforced through the âhidden curriculumâ and to problematize the subject area is contingent on the expectations of the schools in which they teach. Â
Intervention or Involvement : A Video Observational Analysis of Bouncers in Aggressive Encounters
Little is known about how bouncerâpatron interactions may influence a bouncerâs use of physical aggression. To address this gap, we offer a micro-interactional analysis examining real-life aggressive bouncer behavior captured by venue surveillance cameras. Quantitative results show that bouncer physical aggression is associated with interactions in which bouncers are directly involved as a conflict party, but not with interactions where they solely intervene as a third-party. Further, a qualitative analysis of emotional cues identifies anger as a plausible mechanism underpinning bouncer aggression. We consider the implications of these findings for night-time economy violence prevention strategies and discuss the relevance of video data for barroom research
Implicit and explicit pedagogical practices related to sociocultural issues and social justice in physical education teacher education programs
Background: For many years, scholars in PETE have argued for the importance of educating pre-service teachers (PSTs) about equality (e.g., Evans 1990), sociocultural perspectives and issues (e.g., Cliff, Wright and Clarke, 2009; Author 2014) and critical pedagogy (e.g., Fernandez-Balboa 1997; Philpot 2015). Despite this advocacy, we would argue that there are significant differences in how faculty teach about sociocultural issues, and for, social justice. The pedagogical actions through which Physical Education Teacher Educators (PETEs) do this work is the focus of this paper.
Purpose: We investigated the pedagogical approaches and strategies used by PETE faculty to address and educate PSTs about social justice and sociocultural issues related to gender, race, sexuality, (dis)ability, socioeconomic status and religion in their individual PETE programs. In this study, we draw on transformational pedagogy (Ukpokodu 2009; Ovens 2017) as a framework for theorizing the data. Through this study, we highlight the pedagogical practices espoused as those that engender transformative learning.
Data collection and analysis: Data for this interpretive qualitative research study was collected primarily through in-depth semi-structured interviews with over 70 PETEs who work in 48 PETE programs across Australia, Canada, England, Ireland New Zealand, Sweden, and the United States. Furthermore, an informational survey was used to gather demographic data of the participants. The participants, all current PETEs, had a wide range of professional experiences, which included the length of time in the profession, the type of institution employed, educational backgrounds and courses taught. Data analysis was completed using the processes of content analysis and the constant comparative method (Corbin and Strauss 2008).
Findings: Three major themes represent the findings. In the first theme, âIntentional and Explicit Pedagogiesâ we provide descriptions of the approaches and strategies used by PETEs in this study that were planned in advance of the learning experiences. In the second theme, âTeachable Momentsâ we provide examples of how PETEs utilized âteachable momentsâ in implicit and explicit ways to educate PSTs about sociocultural issues. The third theme, âResistance and Constraintsâ captures the individual challenges PETE faculty faced within their courses if, and when, they teach for equity and social justice. The findings suggest that social justice struggles to find an explicit presence within many PETE programs and that educating PSTs about sociocultural issues and social justice is lacking in many PETE programs
Angelman syndrome: advancing the research frontier of neurodevelopmental disorders
This report is a meeting summary of the 2010 Angelman Syndrome Foundation's scientific symposium on the neuroscience of UBE3A. Angelman syndrome is characterized by loss of speech, severe developmental delay, seizures, and ataxia. These core symptoms are caused by maternal allele disruptions of a single geneâUBE3A. UBE3A encodes an E3 ubiquitin ligase that targets certain proteins for proteasomal degradation. This biology has led to the expectation that the identification of Ube3a protein targets will lead to therapies for Angelman syndrome. The recent discovery of Ube3a substrates such as Arc (activity-regulated cytoskeletal protein) provides new insight into the mechanisms underlying the synaptic function and plasticity deficits caused by the loss of Ube3a. In addition to identifying Ube3a substrates, there have also been recent advances in understanding UBE3A's integrated role in the neuronal repertoire of genes and protein interactions. A developmental picture is now emerging whereby UBE3A gene dosage on chromosome 15 alters synaptic function, with deficiencies leading to Angelman syndrome and overexpression associated with classic autism symptomatology
Understanding Cancer Survivorsâ Reasons to Medicate With Cannabis: A Qualitative Study Based on the Theory of Planned Behavior
Background
Prior to nonmedical cannabis legalization in Canada, individuals were only able to access cannabis legally through licensed producers with medical authorization. Now with an additional legal access system designed for nonmedical purposes, it is unclear what factors influence cancer survivorsâ decisions to medicate or not medicate cannabis as a complementary therapy to alleviate their cancer symptoms.
Methods
We recruited cancer survivors via social media. Interested individuals were purposively sampled to ensure maximization in terms of age, sex, and province of residence. Constructs of the Theory of Planned Behavior were explored during the telephone interviews as participants described what influenced their decisions to medicate or not medicate cannabis to manage their symptoms.
Results
Interviews were conducted with 33 cancer survivors. All individuals believed that cannabis would manage their cancer symptoms. Those that chose to medicate with cannabis provided a variety of reasons, including that cannabis was a more natural alternative; that it reduced their overall number of prescription drugs; and that safer products had become available with the legalization of nonmedical cannabis. Some individuals also indicated that support from physicians and validation from family and friends were important in their decision to medicate with cannabis. Individuals who opted not to medicate with cannabis raised concerns about the lack of scientific evidence and/or possible dependency issues. Some also felt their physician\u27s disapproval was a barrier to considering cannabis use.
Conclusions
The findings revealed that recreational legalization made using cannabis appear safer and easier to access for some cancer survivors. However, physiciansâ censure of cannabis use for symptom management was a barrier for survivors considering its use
Conceptualising social justice and sociocultural issues within physical education teacher education: international perspectives
Background: Physical education (PE) and physical education teacher education (PETE) have a substantial literature base that advocates for students to develop a critical consciousness, appreciate multiple perspectives, and engage in actions to enhance social justice (Tinning 2016). Analysing sociocultural issues, critically reflecting on beliefs, knowledge, biography and values, and developing a sense of agency to enact change, have been recognised as an integral part of the PETE knowledge base for some time (FernĂĄndez-Balboa 1997). However, there remain differences in how social justice itself is conceptualised and enacted. Social justice is aligned heavily with critical and âpostâ theories where taking action for justice, democracy and power are central; but social justice is also found in humanist beliefs in student-centredness and equality and has been co-opted by neoliberal forces that promote individual responsibility. While a lack of consensus is not in itself a problem (Bialystok 2014), diverse definitions might contribute to confusion (Randall and Robinson 2016) and lead to uncertainty over what and how to teach for social justice.
Purpose: In order to work towards greater certainty around concepts of social justice in the PETE community, this project sought to map variations in definition and conceptualisation of social justice and sociocultural issues among physical education teacher educators (PETEs) and physical education and sport pedagogy (PESP) educators, as part of a wider project on social justice and sociocultural perspectives and practices in PETE.
Methods: PETE and PESP faculty (n=72) in North America, Europe, and Australasia engaged in an in-depth interview, during which they were asked how they define social justice and sociocultural issues. Additional information about participantsâ social identity was collected. A constant comparative method of analysing participantsâ definitions mapped a range of concepts building on the theoretical framework of neoliberal, humanist, critical and âpostâ approaches to social justice.
Findings: The data demonstrate that there are a range of understandings about sociocultural issues and social justice. Most commonly, some participants articulated a humanist approach to social justice by encouraging their pre-service teachers (PSTs) to have awareness of equality of opportunity in relation to gender, sexuality and/or racism. Less prevalent, but strongly stated by those who conceptualised social justice in these terms, was the importance to take action for democracy, empowerment or critical reflection. The terms diversity and equality, framed in neoliberal and humanist discourses, were most commonly used within the United States (US), while critical pedagogy and alignment with critical and âpostâ theories were more prevalent in Australia and New Zealand.
Conclusion: Differences exist in the ways social justice is conceptualised in PETE. While this can be attributed to the influence of local issues, it is also reflective of what intellectual tools, such as humanism or critical theory, are available for problematising social issues. The range of non-critical concepts found raises concern that PSTs are not getting the tools to enact social justice or tackle sociocultural issues.
- âŠ