290 research outputs found
Staff and student perceptions of assessment value and workload
BACKGROUND AND AIM
As teachers, we aim to design valuable and authentic assessment which engages students purposefully enabling them to demonstrate learning outcomes appropriately. However, the style of assessment and extent of engagement required by the student may differ between subjects and is dependent upon factors such as year level and discipline. Engagement with and design of assessment is further impacted by workload of students and staff respectively. This project explored staff and student perceptions of assessment in the Faculty of Science, Engineering and Technology at the University of Adelaide, allowing the co-creation of guidelines for assessment design/practice.
DESIGN AND METHODS
Students completed surveys in-class (n=98) or online (n=51) with students also participating in 4 focus groups (n=25). Academics completed an online survey (n=34) with n=25 being interviewed.
RESULTS AND DISCUSSION
Regardless of discipline, students prefer to have multiple, and different types, of assessments with low weightings over a semester to enable formative feedback and to demonstrate their learning more easily. They acknowledged the impact on academic workload with most academics indicating that 4-5 assessments per subject were ideal over the semester. Students usually equated the weighting of tasks with the expected workload whereas many academics tended to weight assessment based on the importance of the learning outcomes. Most academics (56%) did not provide guidance to students about their expectations for required workload for individual assignments (at different grade levels).
Final exams were seen by students as the least valuable type of assessment to demonstrate their attainment of learning outcomes. Interestingly, students acknowledged the academics’ viewpoint that final invigilated exams are essential (‘to stop cheating or plagiarism’) and suggested that there should be a hurdle on the final exam but that it be weighted less than 50%. Group assignments were also ranked as less valuable by students and academics. Students did not always see the relevance of working in a group (‘other than to reduce the workload of the academic’) and were often stressed about equal distribution of workload and/or the impact of relying on others for their grade. Academics acknowledged the need to improve how we teach groupwork skills and manage peer assessment.
Students thought the most valuable assessments were low-weighting, online, open-book, weekly quizzes/tests with multiple choice questions (MCQs) because they were ‘for learning’, did not require as much time and were often designed by academics to require higher order learning (such as application and synthesis). Academics indicated that quizzes and mid-semester exams were valuable for reducing pressure of the final exam on students. However, the design and development of appropriate MCQs increased workloads because ‘you have to be clever’ and it ‘just takes too much time’. Practical reports and practical-based activities were also ranked as extremely valuable in the surveys by students and academics. However, focus group discussions with students suggested this was contingent on the relevance of the report or activity to a future role/career.
In conclusion, students are often most concerned about fairness and consistency in assessment but also had a limited understanding of the rationale for assessment design and required input. Therefore, the co-created guidelines include a suggestion that academics provide detailed expectations (especially relating to workload) and information about the purpose of the assessment and its design
Evaluation of Targeted Influenza Vaccination Strategies via Population Modeling
Background
Because they can generate comparable predictions, mathematical models are ideal tools for evaluating alternative drug or vaccine allocation strategies. To remain credible, however, results must be consistent. Authors of a recent assessment of possible influenza vaccination strategies conclude that older children, adolescents, and young adults are the optimal targets, no matter the objective, and argue for vaccinating them. Authors of two earlier studies concluded, respectively, that optimal targets depend on objectives and cautioned against changing policy. Which should we believe? Methods and Findings
In matrices whose elements are contacts between persons by age, the main diagonal always predominates, reflecting contacts between contemporaries. Indirect effects (e.g., impacts of vaccinating one group on morbidity or mortality in others) result from off-diagonal elements. Mixing matrices based on periods in proximity with others have greater sub- and super-diagonals, reflecting contacts between parents and children, and other off-diagonal elements (reflecting, e.g., age-independent contacts among co-workers), than those based on face-to-face conversations. To assess the impact of targeted vaccination, we used a time-usage study\u27s mixing matrix and allowed vaccine efficacy to vary with age. And we derived mortality rates either by dividing observed deaths attributed to pneumonia and influenza by average annual cases from a demographically-realistic SEIRS model or by multiplying those rates by ratios of (versus adding to them differences between) pandemic and pre-pandemic mortalities. Conclusions
In our simulations, vaccinating older children, adolescents, and young adults averts the most cases, but vaccinating either younger children and older adults or young adults averts the most deaths, depending on the age distribution of mortality. These results are consistent with those of the earlier studies
MR spectroscopy-based brain metabolite profiling in propionic acidaemia: metabolic changes in the basal ganglia during acute decompensation and effect of liver transplantation
Background: Propionic acidaemia (PA) results from deficiency of Propionyl CoA carboxylase, the commonest form presenting in the neonatal period. Despite best current management, PA is associated with severe neurological sequelae, in particular movement disorders resulting from basal ganglia infarction, although the pathogenesis remains poorly understood. The role of liver transplantation remains controversial but may confer some neuro-protection. The present study utilises quantitative magnetic resonance spectroscopy (MRS) to investigate brain metabolite alterations in propionic acidaemia during metabolic stability and acute encephalopathic episodes.Methods: Quantitative MRS was used to evaluate brain metabolites in eight children with neonatal onset propionic acidaemia, with six elective studies acquired during metabolic stability and five studies during acute encephalopathic episodes. MRS studies were acquired concurrently with clinically indicated MR imaging studies at 1.5 Tesla. LCModel software was used to provide metabolite quantification. Comparison was made with a dataset of MRS metabolite concentrations from a cohort of children with normal appearing MR imaging.Results: MRI findings confirm the vulnerability of basal ganglia to infarction during acute encephalopathy. We identified statistically significant decreases in basal ganglia glutamate+glutamine and N-Acetylaspartate, and increase in lactate, during encephalopathic episodes. In white matter lactate was significantly elevated but other metabolites not significantly altered. Metabolite data from two children who had received liver transplantation were not significantly different from the comparator group.Conclusions: The metabolite alterations seen in propionic acidaemia in the basal ganglia during acute encephalopathy reflect loss of viable neurons, and a switch to anaerobic respiration. The decrease in glutamine + glutamate supports the hypothesis that they are consumed to replenish a compromised Krebs cycle and that this is a marker of compromised aerobic respiration within brain tissue. Thus there is a need for improved brain protective strategies during acute metabolic decompensations. MRS provides a non-invasive tool for which could be employed to evaluate novel treatments aimed at restoring basal ganglia homeostasis. The results from the liver transplantation sub-group supports the hypothesis that liver transplantation provides systemic metabolic stability by providing a hepatic pool of functional propionyl CoA carboxylase, thus preventing further acute decompensations which are associated with the risk of brain infarction
The Plant Diversity Sampling Design for The National Ecological Observatory Network
The National Ecological Observatory Network (NEON) is designed to facilitate an understanding of the impact of environmental change on ecological systems. Observations of plant diversity—responsive to changes in climate, disturbance, and land use, and ecologically linked to soil, biogeochemistry, and organisms—result in NEON data products that cross a range of organizational levels. Collections include samples of plant tissue to enable investigations of genetics, plot-based observations of incidence and cover of native and non-native species, observations of plant functional traits, archived vouchers of plants, and remote sensing airborne observations. Spatially integrating many ecological observations allows a description of the relationship of plant diversity to climate, land use, organisms, and substrates. Repeating the observations over decades and across the United States will iteratively improve our understanding of those relationships and allow for the testing of system-level hypotheses as well as the development of predictions of future conditions
Hydrogen Susceptibility of Nanostructured Bainitic Steels
Abstract
Nanostructured steels with an ultimate tensile strength of 1.6 GPa were produced with austenite content varying from 0 to 35 vol pct. The effect on the mechanical properties was assessed after saturating the steel with hydrogen. Elongation was reduced to 2 to 5 pct and UTS to 65 to 70 pct of prior value. Thermal desorption measurements confirmed the higher solubility of hydrogen in the steel with higher austenite content. The level of hydrogen saturation was found to correlate to the total area of grain boundaries rather than to the volume fraction of retained austenite.This is the final version of the article. It was first available from Springer via http://dx.doi.org/10.1007/s11661-015-3221-
GCT-03. MonoGerm, a novel proof-of-principle Bayesian phase II trial design of carboplatin or vinblastine monotherapy induction prior to radiotherapy for intracranial germinoma [Abstract]
BACKGROUND
Current European standard-of-care for localised intracranial germinoma is multi-agent chemotherapy (carboPEI: carboplatin/etoposide/ifosfamide) followed by definitive radiotherapy, with excellent survival. MonoGerm is a de-escalation, non-inferiority trial aiming to reduce toxicity. Twelve-week carboplatin (PMID:8039122) AUC10 or vinblastine (PMIDs:32642701/34520101) induction will be evaluated to test if as effective as carboPEI from SIOP-CNS-GCT-II. A novel trial design was required to answer this question pragmatically/safely.
METHODS
Clinical trials in rare diseases recruit slowly, allowing continuous monitoring of efficacy outcomes. Efficacy-transition-pathways (ETP) are innovative visual tools to aid determination of trial design parameters, and an extension of the dose-transition-pathways concept introduced for dose-finding trials (PMID:28733440).
RESULTS
MonoGerm includes two monotherapies, with each single arm recruiting six cohorts of three patients, with interim assessment after each recruited cohort and final analysis at 18 patients (total n=36). Insufficient tumour volume response (<30%) at 6-week safety MRI results in 12-weeks carboPEI. Primary outcome is radiological complete response (CR) by 12-weeks of induction monotherapy. A beta-binomial conjugate analysis will generate posterior probability distributions, combining observed trial data as realisations from a binomial distribution with a minimally informative Beta (1,1) prior. Decision criteria to allow early stopping at interim analyses and go/no-go decisions at final analysis are based on probabilities from these posterior distributions. ETP visually maps out parameters used to assert decisions after each interim assessment as a pyramid decision tree. For each recruited cohort and every CR outcome, estimates of the true CR rate and probabilities with associated decisions are mapped out. ETP allows clear communication between statisticians, clinicians, and patient-public-involvement (PPI) teams, facilitating informed decisions in an efficient/realistic trial design.
CONCLUSION
MonoGerm, a novel Bayesian de-escalation trial, funded by Little Princess Trust (https://www.littleprincesses.org.uk/), uses ETP and continuous monitoring with built-in stopping rules to ensure patient safety in this treatment de-escalation trial
ω-3 Fatty acids for major depressive disorder in adults: an abridged Cochrane review.
OBJECTIVE: To assess the effects of n-3 polyunsaturated fatty acids (n-3PUFAs; also known as ω-3 fatty acids) compared with comparator for major depressive disorder (MDD) in adults. DESIGN: Systematic review and meta-analyses. DATA SOURCES: The Cochrane Depression, Anxiety and Neurosis Review Group's Specialised Registers (CCDANCTR) and International Trial Registries searched to May 2015. CINAHL searched to September 2013. TRIAL SELECTION: INCLUSION CRITERIA: a randomised controlled trial (RCT); that provided n-3PUFAs as an intervention; used a comparator; measured depressive symptomology as an outcome; and was conducted in adults with MDD. OUTCOMES: Primary outcomes were depressive symptomology and adverse events. RESULTS: 20 trials encompassing 26 relevant studies were found. For n-3PUFAs versus placebo, n-3PUFA supplementation resulted in a small-to-modest benefit for depressive symptomology: SMD=-0.32 (95% CI -0.52 to -0.12; 25 studies, 1373 participants, very low-quality evidence), but this effect is unlikely to be clinically meaningful, is very imprecise and, based on funnel plot inspection, sensitivity analyses and comparison with large well-conducted trials, is likely to be biased. Considerable evidence of heterogeneity between studies was also found, and was not explained by subgroup or sensitivity analyses. Numbers of individuals experiencing adverse events were similar in intervention and placebo groups (OR=1.24, 95% CI 0.95 to 1.62; 19 studies, 1207 participants; very low-quality evidence). For n-3PUFAs versus antidepressants, no differences were found between treatments in depressive symptomology (MD=-0.70 (95% CI -5.88 to 4.48); 1 study, 40 participants, very low-quality evidence). CONCLUSIONS: At present, we do not have sufficient evidence to determine the effects of n-3PUFAs as a treatment for MDD. Further research in the form of adequately powered RCTs is needed
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