6,138 research outputs found
Handbook for Learning-centred evaluation of Computer-facilitated learning projects in higher education
This handbook supports a project funded by the Australian Government Committee for University Teaching and Staff Development (CUTSD). The amended project title is “Staff Development in Evaluation of Technology-based Teaching Development Projects: An Action Inquiry Approach”.
The project is hosted by Murdoch University on behalf of the Australasian Society for Computers in Learning in Tertiary Education (ASCILITE), as a consortium of 11 universities.
The rationale of the project is to guide a group of university staff through the evaluation of a Computer-facilitated Learning (CFL1) project by a process of action inquiry and mentoring, supported by the practical and theoretical material contained in this handbook
Cost effective flat plate photovoltaic modules using light trapping
Work in optical trapping in 'thick films' is described to form a design guide for photovoltaic engineers. A thick optical film can trap light by diffusive reflection and total internal reflection. Light can be propagated reasonably long distances compared with layer thicknesses by this technique. This makes it possible to conduct light from inter-cell and intra-cell areas now not used in photovoltaic modules onto active cell areas
The Occurrence of Autoimmune Diseases in Patients with Multiple Sclerosis and Their Families
The aims of this study were to determine whether the occurrence of autoimmune diseases is increased in patients with multiple sclerosis (MS) and their families and whether this is influenced by the type of MS. We conducted a case-control study using a questionnaire design to determine whether the prevalence of 11 autoimmune diseases is increased in patients with MS and their first-degree relatives compared to a random population control group and their first-degree relatives. We found that the total combined prevalence of the 11autoimmune diseases was higher in the MS patients than in the controls, with an odds ratio of 1.7 (95% confidence interval 0.9-3.2; P= 0.10) increasing to 1.9 (1.0-3.5; P= 0.05) after adjusting for age. For persons aged under 60 years, the odds ratio was 2.3 (1.1-4.6). We also found that there was a significant increase in the total combined prevalence of the autoimmune diseases in the first-degree relatives of MS patients compared to the first-degree relatives of the control group (P= 0.003, odds ratio 2.2, confidence interval 1.3-3.7). Patients with primary progressive MS did not differ from patients with relapsing-remitting or secondary progressive MS in the personal or familial occurrence of autoimmune disease. In conclusion, although there were sources of possible bias, this study suggests that individuals with MS have a genetic predisposition to autoimmunity in general
Experimental Evaluation of Several Key Factors Affecting Root Biomass Estimation by 1500 MHz Ground-Penetrating Radar
Accurate quantification of coarse roots without disturbance represents a gap in our understanding of belowground ecology. Ground penetrating radar (GPR) has shown significant promise for coarse root detection and measurement, however root orientation relative to scanning transect direction, the difficulty identifying dead root mass, and the effects of root shadowing are all key factors affecting biomass estimation that require additional research. Specifically, many aspects of GPR applicability for coarse root measurement have not been tested with a full range of antenna frequencies. We tested the effects of multiple scanning directions, root crossover, and root versus soil moisture content in a sand-hill mixed oak community using a 1500 MHz antenna, which provides higher resolution than the oft used 900 MHz antenna. Combining four scanning directions produced a significant relationship between GPR signal reflectance and coarse root biomass (R2 = 0.75) (p \u3c 0.01) and reduced variability encountered when fewer scanning directions were used. Additionally, significantly fewer roots were correctly identified when their moisture content was allowed to equalize with the surrounding soil (p \u3c 0.01), providing evidence to support assertions that GPR cannot reliably identify dead root mass. The 1500 MHz antenna was able to identify roots in close proximity of each other as well as roots shadowed beneath shallower roots, providing higher precision than a 900 MHz antenna. As expected, using a 1500 MHz antenna eliminates some of the deficiency in precision observed in studies that utilized lower frequency antennas
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Eyes on the bog. Long-term monitoring network for UK peatlands
Eyes on the Bog provides a scientifically robust, repeatable, low tech, long-term monitoring initiative.
The standardised methodology enables individual peatland sites to be consistently monitored across the UK, creating a network of comparable sites. The initiative employs cheap, simple techniques and modern technology to enable useful monitoring information to be collected by peatland community employees or volunteers on:
Peat subsidence and carbon loss
Carbon capture
Water table behaviour
Peat soil condition
Vegetation status, structure and composition
Historical context of change and current trajectorie
Effect of magnetic state on the transition in iron: First-principle calculations of the Bain transformation path
Energetics of the fcc () - bcc () lattice transformation by
the Bain tetragonal deformation is calculated for both magnetically ordered and
paramagnetic (disordered local moment) states of iron. The first-principle
computational results manifest a relevance of the magnetic order in a scenario
of the - transition and reveal a special role of the Curie
temperature of -Fe, , where a character of the transformation is
changed. At a cooling down to the temperatures one can expect that
the transformation is developed as a lattice instability whereas for
it follows a standard mechanism of creation and growth of an embryo of the new
phase. It explains a closeness of to the temperature of start of the
martensitic transformation, .Comment: 4 pages, 3 figures, submitted in Phys. Rev. Letter
Disrupted Maturation of the Microbiota and Metabolome among Extremely Preterm Infants with Postnatal Growth Failure
Growth failure during infancy is a major global problem that has adverse effects on long-term health and neurodevelopment. Preterm infants are disproportionately affected by growth failure and its effects. Herein we found that extremely preterm infants with postnatal growth failure have disrupted maturation of the intestinal microbiota, characterized by persistently low diversity, dominance of pathogenic bacteria within the Enterobacteriaceae family, and a paucity of strictly anaerobic taxa including Veillonella relative to infants with appropriate postnatal growth. Metabolomic profiling of infants with growth failure demonstrated elevated serum acylcarnitines, fatty acids, and other byproducts of lipolysis and fatty acid oxidation. Machine learning algorithms for normal maturation of the microbiota and metabolome among infants with appropriate growth revealed a pattern of delayed maturation of the microbiota and metabolome among infants with growth failure. Collectively, we identified novel microbial and metabolic features of growth failure in preterm infants and potentially modifiable targets for intervention
Changes in union membership over time : a panel analysis for West Germany
Despite the apparent stability of the wage bargaining institutions in West Germany, aggregate union membership has been declining dramatically since the early 90's. However, aggregate gross membership numbers do not distinguish by employment status and it is impossible to disaggregate these sufficiently. This paper uses four waves of the German Socioeconomic Panel in 1985, 1989, 1993, and 1998 to perform a panel analysis of net union membership among employees. We estimate a correlated random effects probit model suggested in Chamberlain (1984) to take proper account of individual specfic effects. Our results suggest that at the individual level the propensity to be a union member has not changed considerably over time. Thus, the aggregate decline in membership is due to composition effects. We also use the estimates to predict net union density at the industry level based on the IAB employment subsample for the time period 1985 to 1997. JEL - Klassifikation: J
Determinants of Bacterial Contamination in Pools, Spas, and Wading Pools: Should Chlorine Standards Be Revised?
Using a retrospective case-control study, we compared poolside tests with bacteriological samples during three consecutive summers. A total of 844 matched samples were obtained. Increased chlorine levels were associated with lower rates of contamination. Alkalinity, pH, and TDS were not statistically associated with bacteriological failures. In swimming pools with \u3e 1 ppm of chlorine, 27/30 (90.0%) passed bacteriologic evaluation. In spas with \u3c 1.0 ppm of chlorine, only 12/28 (42.9%) passed. Of the spas with \u3e 3.0 ppm of chlorine, 170/176 (96.6%) passed. Of the wading pools with \u3c 1ppm of chlorine, only 12/25 (48.0%) passed. Of the wading pools with \u3e 2 ppm, 263/290 (90.7%) passed. Of available poolside tests, only chlorine levels are predictive of positive testing for fecal contamination. Higher levels of chlorine were associated with higher passing rates. Current standards for disinfection in spas and wading pools may need to be increased to help prevent contamination
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