Good practice in educational research : An outline using four paradigms

This article employs four different research papers (a case study, an action research project, an ethnography and a quantitative nomothetic study) to illustrate some of the basic concepts which make up sound educational research. Issues such as research design, sampling, data collection, data analysis and validity are all discussed. Particular emphasis is placed in the paper on the need for transparency on the part of researchers when presenting their findings

Failure in composite materials

The economic and efficient exploitation of composite materials in critical load bearing applications relies on the ability to predict safe operational lives without excessive conservatism. Developing life prediction and monitoring techniques in these complex, inhomogeneous materials requires an understanding of the various failure mechanisms which can take place. This article describes a range of damage mechanisms which are observed in polymer, metal and ceramic matrix composites

Ripple Effect Mapping of Youth & Adult Dyad Pairs Demonstrating Community Impact from iCook 4-H Intervention

Introduction: Creating effective dissemination and implementation tools within community based, obesity prevention research is needed to bridge the current science to practice gap. Ripple Effect Mapping (REM) using Community Capitals Framework (CCF) is a community impact evaluation tool that is hypothesized to positively capture activity during dissemination within community programs. Although REM is a proposed impact evaluation method, it has not been widely adopted within the research sector. In order to facilitate the translation of research into evidenced based practice, a stepwise process must be described and tested to determine efficacy and effectiveness, followed by a method to translate findings into useable and understandable information for the immediate users, the community, and larger public.;Purpose: The purpose of this study was to examine REM as an effective impact evaluation tool in determining participants\u27 (youth/adult dyads) perceptions of the ripple effect of a 24 month, iCook 4-H multistate intervention program on self, family and community for future dissemination.;Methods: Seventy dyad (A=adult, Y=youth) participants (35=A, 35=Y ages 9-10 years) participated across 5 states (10 groups; ME, NE, SD, TN, WV). Three core themes of iCook 4-H were assessed: cooking, eating and playing together. Group dyads responded to open ended questions by leader driven dialogue about ways in which the iCook program has affected the individual, family and community. Three main questions were asked: 1) what are people doing differently as a result of the iCook program; 2) who has benefited from the iCook program and how; 3) are there changes in the way community groups and institutions do things as a result of the iCook program? Questions and dialogue were recorded by trained note-takers using a template with set instructions. Directed data content analysis was used to determine individual, family and community impact.;Results: Participants reported adopting new behaviors such as an increase in physical activity, frequency of trying new foods were increased and improved communication skills as well as increased harmony within family units. Directed content analysis resulted in one theme, seven categories with eight subcategories, and 41 supporting subcategories. Participants reported positive family behavior change affecting all capitals within the CCF leading to an amplified awareness of the importance of togetherness.;Conclusions: Findings indicate that the REM evaluation tool was an effective approach in determining participant perceptions for future dissemination and implementation. Additionally, findings show youth obesity prevention programs such as the iCook 4-H program have the potential to positively affect self, families and communities. Applying a tool such as REM can be used by researchers, community members and participants as an effective evaluation tool to demonstrate through a visual mapping image, the positive effects of obesity prevention programs to further the dissemination and implementation mileage, replicability and sustainably

Psycho-markers of weight loss. The roles of TFEQ Disinhibition and Restraint in exercise-induced weight loss

yesEating behaviour traits, namely Disinhibition and Restraint, have the potential to exert an effect on food intake and energy balance. The effectiveness of exercise as a method of weight management could be influenced by these traits. Fifty eight overweight and obese participants completed 12-weeks of supervised exercise. Each participant was prescribed supervised exercise based on an expenditure of 500 kcal/session, 5 d/week for 12-weeks. Following 12-weeks of exercise there was a significant reduction in mean body weight ( 3.26 ± 3.63 kg), fat mass (FM: 3.26 ± 2.64 kg), BMI ( 1.16 ± 1.17 kg/m2) and waist circumference (WC: 5.0 ± 3.23 cm). Regression analyses revealed a higher baseline Disinhibition score was associated with a greater reduction in BMI and WC, while Internal Disinhibition was associated with a larger decrease in weight, %FM and WC. Neither baseline Restraint or Hunger were associated with any of the anthropometric markers at baseline or after 12-weeks. Furthermore, after 12-weeks of exercise, a decrease in Disinhibition and increase in Restraint were associated with a greater reduction in WC, whereas only Restraint was associated with a decrease in weight. Post-hoc analysis of the sub-factors revealed a decrease in External Disinhibition and increase in Flexible Restraint were associated with weight loss. However, an increase in Rigid Restraint was associated with a reduction in %FM and WC. These findings suggest that exercise-induced weight loss is more marked in individuals with a high level of Disinhibition. These data demonstrate the important roles that Disinhibition and Restraint play in the relationship between exercise and energy balance.BBSR

Warp propagation in astrophysical discs

Astrophysical discs are often warped, that is, their orbital planes change with radius. This occurs whenever there is a non-axisymmetric force acting on the disc, for example the Lense-Thirring precession induced by a misaligned spinning black hole, or the gravitational pull of a misaligned companion. Such misalignments appear to be generic in astrophysics. The wide range of systems that can harbour warped discs - protostars, X-ray binaries, tidal disruption events, quasars and others - allows for a rich variety in the disc's response. Here we review the basic physics of warped discs and its implications.Comment: To be published in Astrophysical Black Holes by Haardt et al., Lecture Notes in Physics, Springer 2015. 19 pages, 2 figure

Vertices and the CJT Effective Potential

The Cornwall-Jackiw-Tomboulis effective potential is modified to include a functional dependence on the fermion-gauge particle vertex, and applied to a quark confining model of chiral symmetry breaking.Comment: 10 pages (latex), PURD-TH-93-1

Relationships among tonic and episodic aspects of motivation to eat, gut peptides, and weight before and after bariatric surgery.

yesBackground The interaction between motivation to eat, eating behaviour traits and gut peptides following gastric bypass (GBP) surgery are not fully understood. Setting Danderyd Hospital, Karolinska Institutet, Stockholm, Sweden. Method Appetite and hormone responses to a fixed liquid pre-load were assessed in 12 obese (BMI 45 ± 1.9 kg/m2) participants immediately before, 3 days, 2 months, and 1 year following gastric by-pass (GBP) surgery. Subjective appetite and plasma levels of ghrelin, leptin, insulin and GLP-1 were measured for a 3-hour postprandial period. Eating behaviour traits were also measured using the TFEQR18. Results There was a decrease in TFEQ Emotional Eating (EE) and Uncontrolled Eating (UE) from pre to 1-year post-surgery, but no significant change in Restraint. In addition, there was a reduction in subjective appetite ratings, and alterations in appetite peptides favouring an anorectic response. Pre-surgery EE was significantly related to fasting and AUC ghrelin; UE was associated with AUC desire to eat while there was a significant association between fasting desire to eat and ghrelin (fasting and AUC). 1 year post-surgery, UE was positively related to fasting insulin and Restraint was negatively associated with GLP-1. UE and subjective hunger were positively correlated, while the relationship between desire to eat and ghrelin remained. Conclusion The relationships amongst subjective appetite ratings, eating behaviour traits and appetite peptides in obese patients both before and at one-year post GBP surgery contribute to the reduction in a propensity to over-eat and weight loss

Collider signals from slow decays in supersymmetric models with an intermediate-scale solution to the mu problem

The problem of the origin of the mu parameter in the Minimal Supersymmetric Standard Model can be solved by introducing singlet supermultiplets with non-renormalizable couplings to the ordinary Higgs supermultiplets. The Peccei-Quinn symmetry is broken at a scale which is the geometric mean between the weak scale and the Planck scale, yielding a mu term of the right order of magnitude and an invisible axion. These models also predict one or more singlet fermions which have electroweak-scale masses and suppressed couplings to MSSM states. I consider the case that such a singlet fermion, containing the axino as an admixture, is the lightest supersymmetric particle. I work out the relevant couplings in several of the simplest models of this type, and compute the partial decay widths of the next-to-lightest supersymmetric particle involving leptons or jets. Although these decays will have an average proper decay length which is most likely much larger than a typical collider detector, they can occasionally occur within the detector, providing a striking signal. With a large sample of supersymmetric events, there will be an opportunity to observe these decays, and so gain direct information about physics at very high energy scales.Comment: 24 pages, LaTeX, 4 figure

The mass-to-light ratio of rich star clusters

We point out a strong time-evolution of the mass-to-light conversion factor eta commonly used to estimate masses of unresolved star clusters from observed cluster spectro-photometric measures. We present a series of gas-dynamical models coupled with the Cambridge stellar evolution tracks to compute line-of-sight velocity dispersions and half-light radii weighted by the luminosity. We explore a range of initial conditions, varying in turn the cluster mass and/or density, and the stellar population's IMF. We find that eta, and hence the estimated cluster mass, may increase by factors as large as 3 over time-scales of 50 million years. We apply these results to an hypothetic cluster mass distribution function (d.f.) and show that the d.f. shape may be strongly affected at the low-mass end by this effect. Fitting truncated isothermal (Michie-King) models to the projected light profile leads to over-estimates of the concentration parameter c of delta c ~ 0.3 compared to the same functional fit applied to the projected mass density.Comment: 6 pages, 2 figures, to appear in the proceedings of the "Young massive star clusters", Granada, Spain, September 200