Stereospecific four-bond phosphorus-phosphorus spin couplings in phosphazenyl-phosphazenes

Four-bond phosphorus-phosphorus coupling constants have been measured from the 31P NMR spectra of phosphazenylcyclophosphazenes. Their magnitude appears to be related to the conformation adopted by the phosphazenyl-group relative to the phosphazene ring

High resolution mapping of sediment organic matter from acoustic reflectance data

Spatial mapping of the marine environment is challenging when the properties concerned are difficult to measure except by shore-based analysis of discrete samples of material, usually from sparsely distributed sites. This is the case for many seabed sediment properties. We developed an indirect approach to mapping the organic content of coastal sediments from hydro-acoustic reflectance data. The basis was that both organic matter and acoustic reflectance are related to sediment type and grain size composition. Hence there is a collateral relationship between organic matter content and reflectance properties which can be exploited to enable high resolution mapping. We surveyed an area of seabed off the east coast of Scotland using a vessel mounted single beam echosounder with RoxAnn signal processing. Organic carbon, nitrogen and phytoplankton pigment contents were then measured in material from grab and core samples collected at intervals over a year. Relationships between the organic components and hydroacoustic characteristics were derived by general additive models, and used to construct high resolution maps from the acoustic survey data. Our method is an advance on traditional interpolation techniques sparse spatial data, and represents a generic approach that could be applied to other properties

A GNSS-based method to define athlete manoeuvrability in field-based team sports

This study presented a method of quantifying the manoeuvrability of two field-based team sport athletes and investigated its relationship with running velocity during competition. Across a season, 10 Hz Global navigation satellite system (GNSS) devices were worn during matches by 62 athletes (Australian Football League [AFL]; n = 36, 17 matches, National Rugby League [NRL]; n = 26, 21 matches). To quantify manoeuvrability, tortuosity was calculated from the X and Y coordinates from match GNSS files (converted from latitude and longitude). Tortuosity was calculated as 100 x natural logarithm of the chord distance (distance travelled between X and Y coordinates), divided by the straight-line distance. The maximal tortuosity was then quantified for each 0.5 m∙s-1 speed increment, ranging from 0 to the highest value for each game file. A quadratic model was fitted for each match file, controlling for the curvilinear relationship between tortuosity and velocity. A comparison of the quadratic coefficients between sports, and within sport between positions was investigated using linear mixed models. Resulting standard deviations (SDs) and mean differences were then assessed to establish standardized effect sizes (ES) and 90% confidence intervals (CI). A curvilinear relationship exists between maximal tortuosity and running speed, reflecting that as speed increases, athletes’ ability to deviate from a linear path is compromised (i.e., run in a more linear path). Compared to AFL, NRL had a greater negative quadratic coefficient (a) (ES = 0.70; 0.47 to 0.93) for the 5 second analysis, meaning that as speed increased, NRL athletes’ manoeuvrability reduced at a faster rate than when compared to AFL. There were no positional differences within each sport. GNSS derived information can be used to provide a measure of manoeuvrability tortuosity during NRL and AFL matches. The curvilinear relationship between tortuosity and speed demonstrated that as speed increased, manoeuvrability was compromised

Solid-state metathesis reactions under pressure: A rapid route to crystalline gallium nitride

High pressure chemistry has traditionally involved applying pressure and increasing temperature until conditions become thermodynamically favorable for phase transitions or reactions to occur. Here, high pressure alone is used as a starting point for carrying out rapid, self-propagating metathesis reactions. By initiating chemical reactions under pressure, crystalline phases, such as gallium nitride, can be synthesized which are inaccessible when initiated from ambient conditions. The single-phase gallium nitride made by metathesis reactions under pressure displays significant photoluminescence intensity in the blue/ultraviolet region. The absence of size or surface-state effects in the photoluminescence spectra show that the crystallites are of micron dimensions. The narrow lines of the x-ray diffraction patterns and scanning electron microscopy confirm this conclusion. Brightly luminescent thin films can be readily grown using pulsed laser deposition

Developing professional learning for staff working with children with speech, language and communication needs combined with moderate-to-severe learning difficulties

Children with speech, language and communication needs (SLCN) often present challenges in interaction where teachers may need specialist knowledge. In this article, Carolyn Anderson of the University of Strathclyde examines how teachers and classroom assistants (N=49) developed their professional learning for working with these pupils. A questionnaire revealed limited evidence of pre or post-qualification training in topics or number of hours teaching relating to SLCN. In the absence of formal learning opportunities, most teachers reported learning from others with experience or from reflecting on their own practice. They valued feedback from peers on their teaching practice. The results suggest that school teams should agree on definitions for reflective practice and feedback and how these contribute to professional learning. Lack of access to or availability of formal learning opportunities may be an important factor in shaping teachers' perceptions of their competence and confidence in working with children who have speech, language and communication needs

Land-Use Experiments in the Loch Laidon Catchment

This report presents the results from the Stream Water Quality component of the Loch Laidon catchment land-use experiment which commenced in 1992. The experiment was established with the aim of examining the effects of cattle grazing on the aquatic and terrestrial habitats and biota of a moorland area of upland Scotland

Effects of Diotic Intensity Variations on Auditory Processing in Aphasia

TB

Effects of Selective Binaural Intensity Variations on Auditory Processing in Aphasia

TB