The effects of movement breaks in the classroom on reading

The purpose of this study is to investigate the effect of an increase in physical activity in the classroom on (a) the on-task behavior of special education students and (b) the reading comprehension scores in a READ 180 classroom. The aim of this study is to identify teaching strategies that impact the behavior and academic success of students with special needs. Five sixth graders, three males and two females, with learning disabilities participated in the study. A single-subject ABAB design was used. During the baseline phases, students did independent reading and a reading comprehension assignment without movements immediately beforehand. During the intervention, students participated in a two-to-three minute movement break that incorporated spelling, vocabulary, or grammar review. Words read per minute and percentage correct on the five question comprehension assignment were recorded throughout all phases. Results indicate that students did not increase their on-task behavior or reading comprehension scores after participating in movement breaks. The student satisfaction survey suggests that students enjoyed participating in movement breaks. Further research is suggested to investigate the effects of movement-based lesson activities on the on-task behavior and reading comprehension scores of those with learning disabilities

Climatic and eustatic controls on the development of a Late Triassic source rock in the Jameson Land Basin, East Greenland

This work was undertaken as part of the continuing work of CASP in East Greenland. The sponsoring companies are thanked for their continued support of this work. Help in the field by T. Kinnaird and useful discussions with A. Whitham are gratefully acknowledged. The reviews of L. Clemmensen and an anonymous reviewer, and the input from S. Jones led to improvements to the original paper.Peer reviewedPostprin

Capillary processes increase salt precipitation during CO2 injection in saline formations

An important attraction of saline formations for CO2 storage is that their high salinity renders their associated brine unlikely to be identified as a potential water resource in the future. However, high salinity can lead to dissolved salt precipitating around injection wells, resulting in loss of injectivity and well deterioration. Earlier numerical simulations have revealed that salt precipitation becomes more problematic at lower injection rates. This article presents a new similarity solution, which is used to study the relationship between capillary pressure and salt precipitation around CO2 injection wells in saline formations. Mathematical analysis reveals that the process is strongly controlled by a dimensionless capillary number, which represents the ratio of the CO2 injection rate to the product of the CO2 mobility and air-entry pressure of the porous medium. Low injection rates lead to low capillary numbers, which in turn are found to lead to large volume fractions of precipitated salt around the injection well. For one example studied, reducing the CO2 injection rate by 94 % led to a tenfold increase in the volume fraction of precipitated salt around the injection well

Using blubber explants to investigate adipose function in grey seals:glycolytic, lipolytic and gene expression responses to glucose and hydrocortisone

Adipose tissue is fundamental to energy balance, which underpins fitness and survival. Knowledge of adipose regulation in animals that undergo rapid fat deposition and mobilisation aids understanding of their energetic responses to rapid environmental change. Tissue explants can be used to investigate adipose regulation in wildlife species with large fat reserves, when opportunities for organismal experimental work are limited. We investigated glucose removal, lactate, glycerol and NEFA accumulation in media, and metabolic gene expression in blubber explants from wild grey seals. Glycolysis was higher in explants incubated in 25 mM glucose (HG) for 24 h compared to controls (C: 5.5 mM glucose). Adipose-derived lactate likely contributes to high endogenous glucose production in seals. Lipolysis was not stimulated by HG or high hydrocortisone (HC: 500 nM hydrocortisone) and was lower in heavier animals. HC caused NEFA accumulation in media to decrease by ~30% relative to C in females, indicative of increased lipogenesis. Lipolysis was higher in males than females in C and HG conditions. Lower relative abundance of 11-β-hydroxysteroid dehydrogenase 1 mRNA in HG explants suggests glucose involvement in blubber cortisol sensitivity. Our findings can help predict energy balance responses to stress and nutritional state in seals, and highlight the use of explants to study fat tissue function in wildlife

Theory of Electron-Phonon Dynamics in Insulating Nanoparticles

We discuss the rich vibrational dynamics of nanometer-scale semiconducting and insulating crystals as probed by localized electronic impurity states, with an emphasis on nanoparticles that are only weakly coupled to their environment. Two principal regimes of electron-phonon dynamics are distinguished, and a brief survey of vibrational-mode broadening mechanisms is presented. Recent work on the effects of mechanical interaction with the environment is discussed.Comment: Revte

Potential for natural and enhanced attenuation of sulphanilamide in a contaminated chalk aquifer

Understanding antibiotic biodegradation is important to the appreciation of their fate and removal from the environment. In this research an Isotope Ratio Mass Spectrometry (IRMS) method was developed to evaluate the extent of biodegradation of the antibiotic, sulphanilamide, in contaminated groundwater. Results indicted an enrichment in δ13C of 8.44‰ from − 26.56 (at the contaminant source) to − 18.12‰ (300 m downfield of the source). These results confirm reductions in sulphanilamide concentrations (from 650 to 10 mg/L) across the contaminant plume to be attributable to biodegradation (56%) vs. other natural attenuation processes, such as dilution or dispersion (42%). To understand the controls on sulphanilamide degradation ex-situ microcosms assessed the influence of sulphanilamide concentration, redox conditions and an alternative carbon source. Results indicated, high levels of anaerobic capacity (~ 50% mineralisation) to degrade sulphanilamide under high (263 mg/L), moderate (10 mg/L) and low (0.02 mg/L) substrate concentrations. The addition of electron acceptors; nitrate and sulphate, did not significantly enhance the capacity of the groundwater to anaerobically biodegrade sulphanilamide. Interestingly, where alternative carbon sources were present, the addition of nitrate and sulphate inhibited sulphanilamide biodegradation. These results suggest, under in-situ conditions, when a preferential carbon source was available for biodegradation, sulphanilamide could be acting as a nitrogen and/or sulphur source. These findings are important as they highlight sulphanilamide being used as a carbon and a putative nitrogen and sulphur source, under prevailing iron reducing conditions

The role of matrix cracks and fibre/matrix debonding on the stress transfer between fibre and matrix in a single fibre fragmentation test

The single fibre fragmentation test is commonly used to characterise the fibre/matrix interface. During fragmentation, the stored energy is released resulting in matrix cracking and/or fibre/matrix debonding. Axisymmetric finite element models were formulated to study the impact of matrix cracks and fibre/matrix debonding on the effective stress transfer efficiency (EST) and stress transfer length (STL). At high strains, plastic deformation in the matrix dominated the stress transfer mechanism. The combination of matrix cracking and plasticity reduced the EST and increased STL. For experimental validation, three resins were formulated and the fragmentation of an unsized and uncoupled E-glass fibre examined as a function of matrix properties. Fibre failure was always accompanied by matrix cracking and debonding. With the stiff resin, debonding, transverse matrix cracking and conical crack initiation were observed. With a lower modulus and lower yield strength resin the transverse matrix crack length decreased while that of the conical crack increased. (C) 2011 Elsevier Ltd. All rights reserved

Brittleness index of machinable dental materials and its relation to the marginal chipping factor

OBJECTIVES: The machinability of a material can be measured with the calculation of its brittleness index (BI). It is possible that different materials with different BI could produce restorations with varied marginal integrity. The degree of marginal chipping of a milled restoration can be estimated by the calculation of the marginal chipping factor (CF). The aim of this study is to investigate any possible correlation between the BI of machinable dental materials and the CF of the final restorations. METHODS: The CERECTM system was used to mill a wide range of materials used with that system; namely the Paradigm MZ100TM (3M/ESPE), Vita Mark II (VITA), ProCAD (Ivoclar-Vivadent) and IPS e.max CAD (Ivoclar-Vivadent). A Vickers hardness Tester was used for the calculation of BI, while for the calculation of CF the percentage of marginal chipping of crowns prepared with bevelled marginal angulations was estimated. RESULTS: The results of this study showed that Paradigm MZ100 had the lowest BI and CF, while IPS e.max CAD demonstrated the highest BI and CF. Vita Mark II and ProCAD had similar BI and CF and were lying between the above materials. Statistical analysis of the results showed that there is a perfect positive correlation between BI and CF for all the materials. CONCLUSIONS: The BI and CF could be both regarded as indicators of a material’s machinability. Within the limitations of this study it was shown that as the BI increases so does the potential for marginal chipping, indicating that the BI of a material can be used as a predictor of the CF

IMPACT TESTING OF 18 ADULT MOUTHGUARDS

Mouthguards are used by sports participants to reduce dental injuries, but there is limited evidence of effectiveness of mouthguards. This research compared biomechanical impact performance data from 18 adult mouthguards available in New Zealand. Repeated impact testing was conducted on the centre of each mouthguard mounted on a dental model. The best mouthguards when impact absorption scores were considered were Avaro International, Shock Doctor Power Hilo v4.5 (upper/lower), and Signature Proplus Gel Type 3; The worst mouthguards were Shock Tec Classic and Professional moulded 1 senior custom laminated. Our impact results seem in contrast to other studies which support the belief that custom mouthguards provide superior protection against injury than boil-and-bite mouthguards (which are all usually EVA low stiffness)