MOOCs Meet Measurement Theory: A Topic-Modelling Approach

This paper adapts topic models to the psychometric testing of MOOC students based on their online forum postings. Measurement theory from education and psychology provides statistical models for quantifying a person's attainment of intangible attributes such as attitudes, abilities or intelligence. Such models infer latent skill levels by relating them to individuals' observed responses on a series of items such as quiz questions. The set of items can be used to measure a latent skill if individuals' responses on them conform to a Guttman scale. Such well-scaled items differentiate between individuals and inferred levels span the entire range from most basic to the advanced. In practice, education researchers manually devise items (quiz questions) while optimising well-scaled conformance. Due to the costly nature and expert requirements of this process, psychometric testing has found limited use in everyday teaching. We aim to develop usable measurement models for highly-instrumented MOOC delivery platforms, by using participation in automatically-extracted online forum topics as items. The challenge is to formalise the Guttman scale educational constraint and incorporate it into topic models. To favour topics that automatically conform to a Guttman scale, we introduce a novel regularisation into non-negative matrix factorisation-based topic modelling. We demonstrate the suitability of our approach with both quantitative experiments on three Coursera MOOCs, and with a qualitative survey of topic interpretability on two MOOCs by domain expert interviews.Comment: 12 pages, 9 figures; accepted into AAAI'201

A case study of student evaluation of teaching in university.

This study aims to determine the factors (course characteristics, lecturer characteristics, and tutorial ratings) that affect student evaluation of teaching in university. A total of 88 undergraduates were selected and self-administered questionnaire was used as a tool for data collection. The study found that most of the respondents have high agreement level towards the evaluation of course characteristics, lecturer’s characteristics, and tutorial ratings. Lecturer overall teaching performance ratings were correlated with course characteristics, lecturer characteristics and tutorial rating. Multiple hierarchical analyses found that course’s overall performance ratings was mostly explained by course, followed by lecturer’s characteristics but not from tutorial ratings. From the point of a student, the improved of the teaching effectiveness based on the evaluation process may ultimately enhance knowledge acquisition and, for the educators, the evaluation did provide information for an individual improvement. Faculty would be benefited where the evaluation might lead to fairer promoting, tenure and pay increase decisions for academic staffs

Analysis of the flavonoid component of bioactive New Zealand mānuka (Leptospermum scoparium) honey and the isolation, characterisation and synthesis of an unusual pyrrole

The flavonoid components of New Zealand mānuka (Leptospermum scoparium) honey have been quantified in a series of 31 honeys of varying non-peroxide antibacterial activity to clarify discrepancies between previous studies reported in the literature. Total flavonoid content was 1.16 mg/100 g honey. The principal flavonoids present were pinobanksin, pinocembrin, luteolin and chrysin and together these represented 61% of the total flavonoid content. 1, 2-formyl-5-(2-methoxyphenyl)-pyrrole, which was weakly correlated with the non-peroxide antibacterial activity, was isolated from the flavonoid fraction and separately synthesised. 1 did not display inhibitory activity against Staphylococcus aureus in vitro and thus the origin of the correlation, which is still unknown, is not a direct contribution

Erratum to: The effects of dynamic loading on the intervertebral disc

Loading is important to maintain the balance of matrix turnover in the intervertebral disc (IVD). Daily cyclic diurnal assists in the transport of large soluble factors across the IVD and its surrounding circulation and applies direct and indirect stimulus to disc cells. Acute mechanical injury and accumulated overloading, however, could induce disc degeneration. Recently, there is more information available on how cyclic loading, especially axial compression and hydrostatic pressure, affects IVD cell biology. This review summarises recent studies on the response of the IVD and stem cells to applied cyclic compression and hydrostatic pressure. These studies investigate the possible role of loading in the initiation and progression of disc degeneration as well as quantifying a physiological loading condition for the study of disc degeneration biological therapy. Subsequently, a possible physiological/beneficial loading range is proposed. This physiological/beneficial loading could provide insight into how to design loading regimes in specific system for the testing of various biological therapies such as cell therapy, chemical therapy or tissue engineering constructs to achieve a better final outcome. In addition, the parameter space of ‘physiological' loading may also be an important factor for the differentiation of stem cells towards most ideally ‘discogenic' cells for tissue engineering purpos

Financial Wellbeing of Older Persons in Peninsular Malaysia

The purpose of the study was to investigate the financial wellbeing of older Malaysians and its association with fmancial status, financial literacy, money attitude, financial practices and financial problems. Data for h s cross-sectional study was obtained through interview with 1,841 older persons (55 years and above) in Peninsular Malaysia. Systematically, Seventy-five out of the national total 1,173 sub-&vision/muh (provided by Department of Statistic) was chosen and four Enumeraaon Blocks (EBs) with hghest number of older persons age 55-75 were selected from each sub-&vision. The findmgs of the study revealed that majority of older Malaysians have negative net worth, low in financial literacy, money attitude and moderate financial practices. One thud of the respondents have at least one financial problem over the last year. Respondents who are financially literate have less financial problems. A sipficant relationshp was found between money attitude and financial practices, and also between financial practices and financial satisfaction. Determinants that sipficantly contributed to financial satisfaction were health, income adequacy, financial literacy, money attitude, fmancial practices, financial problems, net worth, home ownership, and ethnicity. However, through an open-ended question, some new factors such as comfortable life, able to cover expenses, pilgnrnage to Mecca, hardworking, phdanthropy are also contributed to the feelmg of financial wellbeing. It is important to educate the population about personal finance, inculcate a positive money attitude and financial practices to public as these d eventually lead to financial wellbeing of an individual

Cost-effectiveness analysis of the management of distal ureteral stones in children

Objective To determine the most cost-effective approach to the management of distal ureteral stones in children given the potential for recurrent renal colic during a trial of passage versus potential stent discomfort and complications of ureteroscopy. Methods We developed a decision tree to project costs and clinical outcomes associated with observation, medical explusive therapy (MET), and ureteroscopy for the management of an index patient with a 4mm distal ureteral stone. We determined which strategy would be least costly and offer the most pain-free days within 30 days of diagnosis. We performed a one-way sensitivity analysis on the probability of successful stone passage with MET. We obtained probabilities from the literature and costs from the 2016 Pediatric Health Information System Database. Results Ureteroscopywas the costliest strategy but maximized the number of pain-free days within 30 days of diagnosis ($5,282/29 pain-free days). MET was less costly than ureteroscopybut also less effective ($615/21.8 pain-free days). Observation cost more than MET and was also less effective ($2,139/15.5 pain-free days). The one-way sensitivity analysis on the probability of successful stone passage with MET demonstrated that ureteroscopyalways has the highest net monetary benefits value and is therefore the recommended strategy given a fixed WTP. Discussion Using a rigorous decision-science approach, we found that ureteroscopy is the recommended strategy in children with small distal ureteral stones. Although it cost more than MET, it resulted in more pain-free days in the first 30 days following diagnosis given the faster resolution of the stone episode

The evolutionary importance of cell ratio between notochordal and nucleus pulposus cells: an experimental 3-D co-culture study

Introduction: Notochordal cells and nucleus pulposus cells are co-existing in the intervertebral disc at various ratios among different mammalians. This fact rises the question about the interactions and the evolutionary relevance of this phenomenon. It has been described that these relatively large notochordal cells are mainly dominant in early lifetime of all vertebrates and then differences occur with ageing. Human, cattle, sheep, and goat lose the cells with age, whereas rodents and lagomorphs maintain these throughout their lifetime. Materials and methods: Here, we addressed the importance of cell ratio using alginate bead 3-D co-culture of bovine nucleus pulposus cells (bNPC) and porcine notochordal cells (pNCs) for 14days using culture inserts. Result: We found a significant stimulation of bNPC in the presence of pNC in terms of cell activity and glycosaminoglycan production, but not for proliferation (DNA content). Relative gene expression was significantly stimulated for collagen type 2 and aggrecan. Conclusion: The stimulating effect of NC was confirmed and the ideal ratio of NPC: NC was found to be ~50:50. This has direct implications for tissue-engineering approaches, which aim to repopulate discs with NP-like precursor cell