8Since the first commercial availability of gas chromatographs coupled with a 9 combustion furnace and an isotope ratio mass spectrometer in 1990, compound 10 specific stable isotope analysis of organic molecules has been at the origin of 11 scientific breakthroughs in a wide range of research fields. The presence of non-12 reacting atoms, however, can mask changes in molecular stable isotopic signatures; 13 position specific isotope analysis (PSIA) is the study of intramolecular isotopic 14 variations. After considering briefly the potential and prospect of this new level in 15 isotopic studies, we review here the handful of existing custom-built systems for on-16 line PSIA using continuous flow isotope ratio mass spectrometry instrumentation and 17 how researchers have addressed issues specific to the technique. We also discuss the 18 various molecular fragmentation processes observed and optimised for various 19 molecules for on-line PSIA as it should help to inform application to new compounds. 20
Reactive attachment disorder (RAD) is one of the least researched and most poorly understood psychiatric disorders. Very little is known about the prevalence and stability of RAD symptoms over time. Until recently it has been difficult to investigate RAD due to limited tools for informing a diagnosis. Utilising a newly developed observational tool along with the Disturbances of Attachment Interview. this short-term prospective longitudinal study explored RAD symptoms in maltreated young children in Scotland (n=100, age range =12-62 months) over 12 months. Children were recruited as part of The Best Services Trial (BeST), in which all infants who came in to the care of the local authority in Glasgow due to child protection concerns were invited to participate. Prevalence of RAD was found to be 5.0% (n=5, 95% CI [0.7-9.3]) when children were first placed in to foster care. Following at least 1 year of improved care conditions, prevalence in the 76 children remaining in the study was 2.1% (n=2, 95% CI [below 0-4.7]). RAD was associated with some mental health and cognitive difficulties. While levels of carer-reported RAD symptoms decreased significantly over time, observed symptoms did not. Findings suggest that RAD resolved in a small majority of cases but further exploration in larger samples would be invaluable.
A six month study was conducted to outline the overall contamination present in Rough Brook stream, Bloxwich, Walsall. Previous studies in the area outlined that the pH of the stream water was far more acidic than expected therefore acid mine drainage as a cause was investigated. Water and soil samples were collected from Rough Brook and compared to selected control sites in the same area. The samples were collected over three sampling periods in order to determine whether seasonal variation occurred in relation to the leaching of contaminants. The samples underwent elemental analysis via ICP and XRF to specify the concentration of suspected contaminants in the stream. Field testing also outlined the pH, conductivity and dissolved oxygen concentrations in the samples collected directly from Rough Brook. The results of the investigation outlined that conductivity and pH values for the water samples collected were similar to the results obtained for the control sites. In contrast the dissolved oxygen concentrations in Rough Brook were affected by the presence of the sewage works downstream of Rough Brook. The ICP analysis outlined seasonal variation for the concentration of elements in Rough Brook. Seasonal variation was portrayed in the concentration of nickel, manganese, iron and magnesium. Therefore there was evidence that Rough Brook was affected by leachates from the historical iron/brass foundries and coal seams close to the stream. Overall, contamination in Rough Brook was found to be a results of acid mine drainage and the sewage outlet. However, the significance of the contamination was minimal.
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