347 resultados para PRIMARY AFFERENT NEURONS
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Bounds on the expectation and variance of errors at the output of a multilayer feedforward neural network with perturbed weights and inputs are derived. It is assumed that errors in weights and inputs to the network are statistically independent and small. The bounds obtained are applicable to both digital and analogue network implementations and are shown to be of practical value.
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Background: Adults with primary brain tumors and their caregivers have significant information needs. This review assessed the effect of interventions to improve information provision for adult primary brain tumor patients and/or their caregivers. Methods: We included randomized or nonrandomized trials testing educational interventions that had outcomes of information provision, knowledge, understanding, recall, or satisfaction with the intervention, for adults diagnosed with primary brain tumors and/or their family or caregivers. PubMed, MEDLINE, EMBASE and Cochrane Reviews databases were searched for studies published between 1980 and June 2014. Results: Two randomized controlled, one non-randomized controlled, and 10 single group pre-post trials enrolled more than 411 participants. Five group, four practice/process change and four individual interventions assessed satisfaction (12 studies), knowledge (four studies) or information provision (2 studies). Nine studies reported high rates of satisfaction. Three studies showed statistically significant improvements over time in knowledge and two showed greater information was provided to intervention than control group participants, although statistical testing was not performed. Discussion: The trials assessed intermediate outcomes such as satisfaction, and only 4/13 reported on knowledge improvements. Few trials had a randomized controlled design and risk of bias was either evident or could not be assessed in most domains.
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Preservice teachers articulate the need for more teaching experiences for developing their practices, however, extending beyond existing school arrangements may present difficulties. Thus, it is important to understand preservice teachers’ development of pedagogical knowledge practices when in the university setting. This mixed-method study investigated 48 second-year preservice teachers’ development of pedagogical knowledge practices as a result of co-teaching primary science to peers. Data were collected through a survey, video-recorded lessons, extended written responses and researcher observations. The study showed how these preservice teachers demonstrated 9 of 11 pedagogical knowledge practices within the co-teaching arrangement. However, research is needed to determine the level of development on each pedagogical knowledge practice and how these practices can be transferred into authentic primary classroom settings.
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STEM education is a new frontier in Australia, particularly for primary schools. However, the E in STEM needs to have a stronger focus with science and mathematics concepts aligned to the presiding curricula. In addition, pedagogical knowledge practices such as planning, preparation, teaching strategies, assessment and so forth need to be connected to key concepts for developing a STEM education. One of the aims of this study was to understand how a pedagogical knowledge practice framework could be linked to student outcomes in STEM education. Specifically, this qualitative research investigated Year 4 students’ involvement in an integrated STEM education program that focused on science concepts (e.g., states of matter, testing properties of materials) and mathematics concepts (such as 3D shapes and metric measurements: millilitres, temperature, grams, centimetres) for designing, making and testing a strong and safe medical kit to insulate medicines at desirable temperatures. Eleven pedagogical knowledge practices (e.g., planning, preparation, teaching strategies, classroom management, and assessment) were used as a framework for understanding how teaching may be linked to student outcomes in STEM education. For instance, “planning” involved devising a student booklet as a resource for students to understand the tasks required of them, which also provided space for them to record ideas, results and information. Planning involved linking national and state curriculum documents to the STEM education activities. More studies are required around pedagogical knowledge frameworks to understand what students learn when involved in STEM education, particularly with the inclusion of engineering education.
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Feedforward inhibition deficits have been consistently demonstrated in a range of neuropsychiatric conditions using prepulse inhibition (PPI) of the acoustic startle eye-blink reflex when assessing sensorimotor gating. While PPI can be recorded in acutely decerebrated rats, behavioural, pharmacological and psychophysiological studies suggest the involvement of a complex neural network extending from brainstem nuclei to higher order cortical areas. The current functional magnetic resonance imaging study investigated the neural network underlying PPI and its association with electromyographically (EMG) recorded PPI of the acoustic startle eye-blink reflex in 16 healthy volunteers. A sparse imaging design was employed to model signal changes in blood oxygenation level-dependent (BOLD) responses to acoustic startle probes that were preceded by a prepulse at 120 ms or 480 ms stimulus onset asynchrony or without prepulse. Sensorimotor gating was EMG confirmed for the 120-ms prepulse condition, while startle responses in the 480-ms prepulse condition did not differ from startle alone. Multiple regression analysis of BOLD contrasts identified activation in pons, thalamus, caudate nuclei, left angular gyrus and bilaterally in anterior cingulate, associated with EMGrecorded sensorimotor gating. Planned contrasts confirmed increased pons activation for startle alone vs 120-ms prepulse condition, while increased anterior superior frontal gyrus activation was confirmed for the reverse contrast. Our findings are consistent with a primary pontine circuitry of sensorimotor gating that interconnects with inferior parietal, superior temporal, frontal and prefrontal cortices via thalamus and striatum. PPI processes in the prefrontal, frontal and superior temporal cortex were functionally distinct from sensorimotor gating.
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This research project examined the potential for circumventing drawing in the ideation process by adopting digital sculpture as the primary conceptual development and design tool for the digital sculpting of creature designs. Through a series of experimental research cycles, multiple frameworks were explored with the aim of identifying a methodology for creating '3D sculpted sketches' for the initial phases of the ideation process. This research project acknowledges that drawing still remains the predominant method of visualising design ideas for characters and creatures for many artists. However, alongside other ideation techniques digital sculpting can function as a rapid and responsive tool to visualize and explore forms in a digital sculpting environment for the conceptualisation of multiple creature design variations. The results of this study are significant for emerging digital sculptors who may not necessarily have a well-defined creative brief or initial concept.
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Purpose: To determine the extent to which the accuracy of magnetic resonance imaging (MRI) based virtual 3-dimensional (3D) models of the intact orbit can approach that of the gold standard, computed tomography (CT) based models. The goal was to determine whether MRI is a viable alternative to CT scans in patients with isolated orbital fractures and penetrating eye injuries, pediatric patients, and patients requiring multiple scans in whom radiation exposure is ideally limited. Materials and Methods: Patients who presented with unilateral orbital fractures to the Royal Brisbane and Women’s Hospital from March 2011 to March 2012 were recruited to participate in this cross-sectional study. The primary predictor variable was the imaging technique (MRI vs CT). The outcome measurements were orbital volume (primary outcome) and geometric intraorbital surface deviations (secondary outcome)between the MRI- and CT-based 3D models. Results: Eleven subjects (9 male) were enrolled. The patients’ mean age was 30 years. On average, the MRI models underestimated the orbital volume of the CT models by 0.50 0.19 cm3 . The average intraorbital surface deviation between the MRI and CT models was 0.34 0.32 mm, with 78 2.7% of the surface within a tolerance of 0.5 mm. Conclusions: The volumetric differences of the MRI models are comparable to reported results from CT models. The intraorbital MRI surface deviations are smaller than the accepted tolerance for orbital surgical reconstructions. Therefore, the authors believe that MRI is an accurate radiation-free alternative to CT for the primary imaging and 3D reconstruction of the bony orbit. �
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This paper explores in-service primary teachers' views and beliefs about culture, learning, teaching and knowledge. Fifty Bachelor of Education in-service primary teachers at a university in Fiji participated in the study. The analysis reveals a mix of old and new beliefs about culture, learning teaching and knowledge. The influence of globalization of technology is a contributing factor towards changing views. To keep the indigenous epistemologies alive and valued like the Western epistemologies, more effort is needed to integrate these in formal education. This has implications for the future professional preparation of pre-service and in-service teachers.
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Post traumatic stress disorder (PTSD) is a serious medical condition effecting both military and civilian populations. While its etiology remains poorly understood it is characterized by high and prolonged levels of fear responding. One biological unknown is whether individuals expressing high or low conditioned fear memory encode the memory differently and if that difference underlies fear response. In this study we examined cellular mechanisms that underlie high and low conditioned fear behavior by using an advanced intercrossed mouse line (B6D2F1) selected for high and low Pavlovian fear response. A known requirement for consolidation of fear memory, phosphorylated mitogen activated protein kinase (p44/42 (ERK) MAPK (pMAPK)) in the lateral amygdala (LA) is a reliable marker of fear learning-related plasticity. In this study, we asked whether high and low conditioned fear behavior is associated with differential pMAPK expression in the LA and if so, is it due to an increase in neurons expressing pMAPK or increased pMAPK per neuron. To examine this, we quantified pMAPK-expressing neurons in the LA at baseline and following Pavlovian fear conditioning. Results indicate that high fear phenotype mice have more pMAPK-expressing neurons in the LA. This finding suggests that increased endogenous plasticity in the LA may be a component of higher conditioned fear responses and begins to explain at the cellular level how different fear responders encode fear memories. Understanding how high and low fear responders encode fear memory will help identify novel ways in which fear-related illness risk can be better predicted and treated.
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Children are particularly susceptible to air pollution and schools are examples of urban microenvironments that can account for a large portion of children’s exposure to airborne particles. Thus this paper aimed to determine the sources of primary airborne particles that children are exposed to at school by analyzing selected organic molecular markers at 11 urban schools in Brisbane, Australia. Positive matrix factorization analysis identified four sources at the schools: vehicle emissions, biomass burning, meat cooking and plant wax emissions accounting for 45%, 29%, 16% and 7%, of the organic carbon respectively. Biomass burning peaked in winter due to prescribed burning of bushland around Brisbane. Overall, the results indicated that both local (traffic) and regional (biomass burning) sources of primary organic aerosols influence the levels of ambient particles that children are exposed at the schools. These results have implications for potential control strategies for mitigating exposure at schools.
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This article reports the findings of an empirical study of outcomes experienced by abducting primary-carer mothers and their children post-return to Australia under the Hague Child Abduction Convention. The study specifically focused on legal and factual outcomes post-return to Australia as the child's habitual residence. The study contributes an original critique of the Convention's operation by examining the collective operation of Convention return proceedings and Pt VII proceedings under the Family Law Act 1975 (Cth) post-return. Convention return proceedings, and the resolution of the substantive parenting dispute post-return to Australia, are not distinct stages operating in isolation. Viewing them as such is a purely theoretical exercise divorced from the reality of the lives of transnational families. Arguably, a better measure of the Convention's success is the outcomes it produces as part of the entire system designed to address the contemporary problem of international parental child abduction. When a child is returned to Australia this system includes the operation of Australian family law.
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This paper investigates the effects of primary school choices on cognitive and non-cognitive development in children using data from the Longitudinal Study of Australian Children (LSAC). We militate against the measurement problems that are associated with individual unobserved heterogeneity by exploiting the richness of LSAC data and applying contemporary econometric approaches. We find that sending children to Catholic or other independent primary schools has no significant effect on their cognitive and non-cognitive outcomes. The literature now has evidence from three different continents that the returns to attending Catholic primary schools are no different than public schools.