Reimagining the General Health Questionnaire as a measure of emotional wellbeing: A study of postpartum women in Malta

Background: Postpartum health has been subject to a focus on psychological morbidity, despite positive associations between postpartum recovery and maternal emotional wellbeing. There are currently many validated tools to measure wellbeing and related concepts, including non-psychiatric morbidity. The General Health Questionnaire, 12 items (GHQ-12) is one such instrument, widely used and validated in several languages. Its use in postpartum settings has been documented with disagreement about the instrument's utility in this population, particularly in relation to scoring method and threshold. The GHQ-12 has never been translated into Maltese. This study explored the psychometric properties of the GHQ-12 in a Maltese postpartum population to consider if the use of a different scoring method (visual analogue scale) in the GHQ-12 can determine postpartum wellbeing. Methods: One hundred and twenty-four postpartum women recruited from one hospital in Malta completed the translated and adapted GHQ-12 as a wellbeing measure (GHQ-12(WB)) at four postpartum time points. The psychometric properties of the GHQ-12(WB) were explored using confirmatory factor analysis, discriminant and divergent validity and reliability analysis. Results: The GHQ-12(WB) demonstrated good divergent and known-groups validity and internal consistency. No models offered a good fit to the data. The overall consistent best-fit to the data was an eight item, two factor model (GHQ-8). Model fit improved across all models in terms of CFI at 13 weeks. Conclusion: Findings generally support the reliability and validity of the Maltese version of the GHQ-12(WB). Model fit changes over time reflect the dynamic nature of postpartum recovery. Further evaluation of the GHQ-8(WB) is recommended. © 2013 Australian College of Midwives

Combined high vacuum/high frequency fatigue tester

Apparatus permits application of significantly greater number of cycles or equivalent number of cycles in shorter time than conventional fatigue test machines. Environment eliminates problems associated with high temperature oxidation and with sensitivity of refractory alloy behavior to atmospheric contamination

Amplitudes and Resonances from an Energy-Dependent Analysis of pbar+p -> pi+pi

The amplitudes at a series of discrete energies obtained from a previuos analysis of pbar+p -> pi+pi have been used as input to a global energy- dependent analysis of data in the momentum range 360 - 1550 MeV/c. The results confirm the previous analysis and yield refined values for meson resonance parameters in this energy region.Comment: 8 pages, LaTex, 2 postscript figures, a reference is correcte

Experiences with Problem-Based Learning: Virginia Initiative for Science Teaching and Achievement

The Virginia Initiative for Science Teaching and Achievement (VISTA) provides high-quality professional development for teachers and administrators to enhance the quality of their science instructional programs. One emphasis of this program is helping teachers learn to implement Problem-Based Learning in the elementary science classroom. Problem-Based Learning (PBL) has the potential to produce significant positive outcomes for students, such as increased student engagement, and opportunities for in-depth critical thinking [1]. Teachers find PBL challenging because it does take additional time for planning and material acquisition, but experience has shown that the benefits outweigh these challenges. Setting clear goals, identifying specific learning objectives, and developing big questions that tie these together help increase the success of the unit. Additionally, administrators can help teachers succeed in implementing a Problem-Based Learning unit by understanding the dynamic nature of the PBL environment, providing flexibility with unit pacing, and setting aside time for refining, reflection, and revision of the unit

Cut Size Statistics of Graph Bisection Heuristics

We investigate the statistical properties of cut sizes generated by heuristic algorithms which solve approximately the graph bisection problem. On an ensemble of sparse random graphs, we find empirically that the distribution of the cut sizes found by ``local'' algorithms becomes peaked as the number of vertices in the graphs becomes large. Evidence is given that this distribution tends towards a Gaussian whose mean and variance scales linearly with the number of vertices of the graphs. Given the distribution of cut sizes associated with each heuristic, we provide a ranking procedure which takes into account both the quality of the solutions and the speed of the algorithms. This procedure is demonstrated for a selection of local graph bisection heuristics.Comment: 17 pages, 5 figures, submitted to SIAM Journal on Optimization also available at http://ipnweb.in2p3.fr/~martin

Seasat altimeter height calibration

The Seasat altimeter was calibrated for height bias using four overflight passes of Bermuda which were supported by the Bermuda laser. The altimeter data was corrected for: tides, using recorded tide gauge data; propagation effects, using meteorological data taken around the time of each pass; acceleration lag; and sea state bias, including both surface effects and instrumental effects. Altimeter data for each of the four passes was smoothed and extrapolated across the island. Interpolation between passes then produced an equivalent altimeter measurement to the geoid at the laser site, so that the altimeter bias could be estimated without the use of a geoid model. The estimated height bias was 0.0 + or - 0.07

Calibration validation for the GEOS-3 altimeter

The absolute bias calibration for the GEOS-3 intensive mode altimeter was measured using two satellite passes whose groundtracks were within 1 km of the Bermuda laser station. The Bermuda laser tracked on the two passes, and was supported by two other NASA lasers on one pass and by the NASA Spacecraft Tracking and Data Network on the other pass. For each pass, the altimeter data around Bermuda was smoothed and extrapolated to the point closest to overhead at the laser site. After correcting for tide heights and sea state effects, the two passes give calibration biases which are in agreement to within 26 cm and have a weighted mean of -5.69 + or - 0.16m for correcting altimeter measurements to the center-of-mass of the spacecraft (i.e., including the antenna tracking point correction). It was found impossible to reconcile the two calibration passes, as well as a set of altimeter crossovers in the middle of the GEOS-3 calibration area, without allowing for a data time tag error. On the bias of a selected set of four crossovers, and an assessment of probable sources of timing error, it was concluded that one interpulse period (10.24 msec) should be added to the data time tags