Sleep, anxiety and challenging behaviour in children with intellectual disability and/or autism spectrum disorder

Children with an intellectual disability (ID) and/or autism spectrum disorder (ASD) are known to suffer from significantly more sleep problems, anxiety and challenging behaviour (CB) than typically developing children (TD), yet little is known about the relationship between these factors in the child ID/ASD population. The study aim was to examine these relationships. We hypothesised that there would be significant positive correlations between the three factors and that sleep problems and anxiety would predict a significant amount of the variance in levels of CB. Parental measures of sleep problems, anxiety and CB were completed by 187 parents of children with ID and/or ASD. Significant positive associations were found between the three factors. A hierarchical multiple regression showed that medication, sleep problems and anxiety accounted for 42% of the variance in CB, with a large effect size. These findings suggest that these relationships should be considered during clinical practice, particularly in the case of CB interventions where sleep problems and/or anxiety are also present

The evolution of layered, basic plutons - evidence from small-scale structures

Many basic and ultrabasic plutons are commonly lithologically, texturally and compositionally layered on several scales. Associated with and defined by, the layering are a variety of small-scale structures, considered analogous to structures found in sedimentary rocks, and capable of interpretation using similar techniques. Observations on these small-scale structures are vised to infer the "depositional" and "diagenetic" processes that operated during the solidification of a number of' plutons. Erosion structures and structures associated with lithic fragments indicate that physical redistribution of solids, crystals and rock fragments, was an important process in the evolution of these bodies and that plagioclase was deposited at the floor even where it was less dense than the contemporary magma. From their relationships with lithic fragments normally graded layers are demonstrated to be the solidified remnants of crystal-laden density currents flowing across the transient floor of the magma chamber and are inferred to be the best approximation to truly chronostratigraphic horizons in layered plutons identified to date. The proposition that crystal- and rock-laden density currents can transport material vertically through the magma body is investigated experimentally by examining the nature of such flows in a small tank, Experiments and calculations indicate that such density currents straddle the range of conditions from laminar to fully turbulent. Laminar flows do not mix with the contemporary magma and will transport crystals to the transient chamber floor. It is suggested that such a process may have given rise to lensoid mafic layers of limited areal extent in the Kiglapait intrusion. Structures inferred to have formed during the "diagenetic" stage of the formation of the layered rocks include deformation structures, layers and replacement bodies. Examples of the latter two sets of structures are shown to have textures identical to those in rocks interpreted as cumulates and it is concluded that those textures alone are not sufficient basis on which to infer crystal growth from the contemporary magma. Many of the structures testify to the former presence of mobile pore liquids and the contemporaneity of pore liquids of different compositions. Movement of pore liquid is considered to have been driven by density differences due to variations in pore magma composition and thus the structures can be considered as evidence for interstitial compositional convection. Under certain circumstances pore liquids may be expelled from the crystal mush and mix with the contemporary magma. The chemical consequences of such mixing events are discussed and it is proposed that chromitite layers in the Eastern Layered Series of the Rum intrusion record the operation of the process. Several features of the Rum intrusion suggest that the magma chamber was thermally and compositionally zoned at times during its active history and this leads to the formulation of a new scheme for the formation of cyclic stratigraphy in the Rum layered intrusion, based on the progradation and regression of a liquid/liquid interface and two environments of accumulation

Characterization of free radicals in clathrate hydrates of pyrrole, thiophene and isoxazole by muon spin spectroscopy

Gas hydrates have long been of interest to the petrochemical industry but there has been growing interest in potential applications for carbon dioxide sequestration and hydrogen storage. This has prompted many fundamental studies of structure and host-guest interactions, but there has been relatively little investigation of chemical reactions of the guest molecules. In previous work we have shown that it is possible to use muon spin spectroscopy to characterize H-atom-like muonium and muoniated free radicals formed in clathrate hydrates. Muonium forms in clathrate hydrates of cyclopentane and tetrahydrofuran, whereas furan and its dihydro- derivatives form radicals. The current work extends studies to clathrates hydrates of other 5-membered heterocycles: thiophene, pyrrole and isoxazole. All form structure II hydrates. In addition to the clathrates, pure liquid samples of the heterocycles were studied to aid in the assignment of radical signals and for comparison with the enclathrated radicals. Similar to furan, two distinct radicals are formed when muonium reacts with thiophene and pyrrole. However, only one muoniated radical was detected from isoxazole. Muon, proton and nitrogen hyperfine constants were determined and compared with values predicted by DFT calculations to aid the structure assignments. The results show that Mu adds preferentially to the carbon adjacent to the heteroatom in thiophene and pyrrole, and to the carbon adjacent to O in isoxazole. The same radicals are formed in clathrates, but the spectra have broader signals, suggesting slower tumbling. Furthermore, additional signals in the avoided level-crossing spectra indicate anisotropy consistent with restricted motion of the radicals in the clathrate cages

Effect of Oatmeal on Postprandial Vascular Compliance Following a High Fat Meal

Background and aim: Postprandial hyperlipidaemia has been associated with acute cardiovascular effects e.g. endothelial dysfunction and peripheral vasodilatation. Oats have known health benefits, and may reduce the transient, post-prandial endothelial dysfunction. The aim of this short study was to investigate if markers of endothelial function pulse wave velocity (PWV) and augmentation index corrected for heart rate (AIx@75) are affected by a meal with varying levels of saturated fat, with or without oatmeal. Methods and results: Fourteen subjects (aged between 22 and 51 years) were recruited. On their first visit, following baseline measurements of anthropometry, blood pressure (BP), heart rate (HR), PWV and AIx@75, they were given one of three meals (low fat, high fat, and high fat with 60g oatmeal) in a randomised order. Subjects returned three hours later for re-assessment of BP, PWV and AIx@75. Visits two and three followed the same protocol, but only BP, HR, PWV and AIx@75 were measured. There was a significant correlation between baseline PWV and systolic pressure (p<0.02), and AIx@75 and diastolic pressure (p<0.005). AIx@75 was positively related to BMI and waist circumference (p<0.01 and p<0.005 respectively). AIx@75 fell following the high fat meal (p<0.05), but not when oats were taken. Heart rate increased following the high fat meal with oats (p<0.05), but no differences were found between fasting and postprandial PWV after any of the meals. Conclusion: AIx@75 was correlated with BMI and waist circumference. The decrease in AIx@75 following the high fat meal requires further investigation, and AIx@75 is possibly a more sensitive marker of arterial compliance than PWV in a young healthy population.sch_die2pub4327pub

Free Radical Reactivity of a Phosphaalkene Explored Through Studies of Radical Isotopologues

Muonium (Mu), an H atom analogue, is employed to probe the addition of free radicals to the P=C bond of a phosphaalkene. Specifically, two unprecedented muoniated free radicals, MesP•-CMu(Me)2 (1a, minor product) and MesPMu-C•Me2 (1b, major product), were detected by muon spin spectroscopy (µSR) when a solution of MesP=CMe2 (1: Mes = 2,4,6-trimethylphenyl) was exposed to a beam of positive muons (µ+). The µ+ serves as a source of Mu (i.e. Mu = µ+ + e–). To confirm the identity of the major product 1b, its spectral features were compared to its isotopologue, MesPH-C•(Me)CH2Mu (2a). Conveniently, 2a is the sole product of the reaction of MesPH(CMe=CH2) (2) with Mu. For all observed radicals, muon, proton and phosphorus hyperfine coupling constants were determined by µSR and compared to DFT-calculated values

An investigation of the post-prandial effects of a meal rich in long-chain omega-3 fatty acids

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Investigation of H atom and free radical behaviour in clathrate hydrates of organic molecules

Clathrate hydrates are icy materials composed of a lattice of water molecules containing well-defined cavities which can accommodate small guest molecules. Their large storage capacity makes clathrates attractive media for a variety of gas storage and separation applications, but there is relatively little information on the chemical stability and diffusion of guest molecules. At the fundamental level inter-cage transition energies have been calculated, but the results need to be tested with experimental data. Ideally this should involve single-atom transport, using an isotopic tracer or spin label. Muonium (Mu = µ+e–) qualifies on both counts. As a single-electron atom with the muon as nucleus it may be considered a light isotope of hydrogen. Furthermore muonium and its reaction products may be monitored by muon spin spectroscopy. In recent years we have used this method to probe H-atom and free radical behaviour in clathrate hydrates. The current work extends studies to benzene and acetone clathrate hydrates. Of note is the simultaneous detection of muonium and muoniated radicals in the same sample. This can happen when Mu is trapped in an empty cavity, remote from its reaction partner. Increase in temperature leads to transport of Mu between cages and results in encounters with reactive guest molecules. By studying the temperature dependence of Mu and radical signals, we have been able to determine the activation energy for transport of Mu between cavities

Analysis of musculoskeletal and breast tumours by fast field-cycling MRI

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