Naresuan University Journal
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Observations of cloud microphysics and ice formation during COPE
We present microphysical observations of cumulus clouds measured over the southwest peninsula of the UK during the COnvective Precipitation Experiment (COPE) in August 2013, which are framed into a wider context using ground-based and airborne radar measurements. Two lines of cumulus clouds formed in the early afternoon along convergence lines aligned with the peninsula. The lines became longer and broader during the afternoon due to new cell formation and stratiform regions forming downwind of the convective cells. Ice concentrations up to 350gLg'1, well in excess of the expected ice nuclei (IN) concentrations, were measured in the mature stratiform regions, suggesting that secondary ice production was active. Detailed sampling focused on an isolated liquid cloud that glaciated as it matured to merge with a band of cloud downwind. In the initial cell, drizzle concentrations increased from g1/4 0.5 to g1/4 20gLg'1 in around 20 min. Ice concentrations developed up to a few per litre, which is around the level expected of primary IN. The ice images were most consistent with freezing drizzle, rather than smaller cloud drops or interstitial IN forming the first ice. As new cells emerged in and around the cloud, ice concentrations up to 2 orders of magnitude higher than the predicted IN concentrations developed, and the cloud glaciated over a period of 12&ndash;15 min. Almost all of the first ice particles to be observed were frozen drops, while vapour-grown ice crystals were dominant in the latter stages. Our observations are consistent with the production of large numbers of small secondary ice crystals/fragments, by a mechanism such as Hallett&ndash;Mossop or droplets shattering upon freezing. Some of the small ice froze drizzle drops on contact, while others grew more slowly by vapour deposition. Graupel and columns were seen in cloud penetrations up to the &minus;12g°C level, though many ice particles were mixed habit due to riming and growth by vapour deposition at multiple temperatures. Our observations demonstrate that the freezing of drizzle/raindrops is an important process that dominates the formation of large ice in the intermediate stages of cloud development. As these frozen drops were the first precipitation observed, interactions between the warm-rain and secondary ice production processes appear to be key to determining the timing and location of precipitation.</p
Short-Term Outcomes for Opiate and Crack Users Accessing Treatment:The Effects of Criminal Justice Referral and Crack Use
Background/aims: The English drug treatment population doubled in size between 1998 and 2008, increasingly characterised by crack cocaine use and criminal justice system (CJS) referral. We assessed short-term (median 3.5 month) behaviour changes following participation in drug treatment and the moderating effect of CJS referral/crack use.Methods: Opiate and/or crack cocaine users (n = 1,267) were recruited from 342 agencies. Outcome effects were assessed via interaction term regression, clustered at participant level, controlling for client characteristics. Treatment retention effects were tested via Cox proportional hazard models.Results: Statistically significant improvements in health, drug use and offensive behaviour were observed (e.g. heroin use from 87 to 51%, acquisitive offending from 47 to 23%). Referral route was not associated with variation in outcomes. Crack use at baseline was associated with a greater chance of non-fatal overdose at follow-up (p = 0.035, 95% CI 1.08-8.20) but a greater reduction in offending income (p = 0.002, 95% CI £104-£419).Conclusion: Despite changes in the English drug treatment population, equivalent short-term improvements in client behaviour were observed a decade earlier. Outcomes for CJS-referred clients were comparable to non-CJS. Crack use at treatment entry offered some scope for greater improvements in offending but may be a barrier to cessation of mortality-associated risky behaviour.</p
Assessing the reliability of the Five Minute Speech Sample against the Camberwell Family Interview in a Chronic Fatigue Syndrome sample
UK Experience of Consortia Engineering for Nuclear Power Stations
These notes review the experience of individuals employed in the engineering and project management of the UK’s programmes of gas-cooled projects, as lessons from that formative period may be relevant to re-establishing a nuclear power programme in this country. The dominant lesson is that to be economic and safe to operate each new project should be planned and controlled by an organization which has the engineering and managerial capacity and authority to integrate and control the design and supply of the whole project
A critical narrative analysis of shared decision-making in acute inpatient mental health care
Shared decision-making (SDM) is a high priority in healthcare policy and is complementary to the recovery philosophy in mental health care. This agenda has been operationalised within the Values- Based Practice (VBP) framework, which offers a theoretical and practical model to promote democratic interprofessional approaches to decision-making. However, these are limited by a lack of recognition of the implications of power implicit within the mental health system. This study considers issues of power within the context of decision-making and examines to what extent decisions about patients’ care on acute in-patient wards are perceived to be shared. Focus groups were conducted with 46 mental health professionals, service users, and carers. The data were analysed using the framework of critical narrative analysis (CNA). The findings of the study suggested each group constructed different identity positions, which placed them as inside or outside of the decision-making process. This reflected their view of themselves as best placed to influence a decision on behalf of the service user. In conclusion, the discourse of VBP and SDM needs to take account of how differentials of power and the positioning of speakers affect the context in which decisions take place
Parental Migration, Intergenerational Obligations and the Paradox for Left-Behind Boys in Rural China
Drawing on in-depth interviews with caregivers of left-behind children (LBC) in rural China, this article seeks to explore their understanding of migration motives and the social process of taking on care-giving roles for LBC. The authors argue that there are underlying socio-cultural explanations pertaining to economic motives for migration; such as, making contributions to social events (weddings and funerals) in village life, and fulfilling social obligations for left-behind sons’ futures. Parents migrate to save for sons’, but not daughters’, adult lives. Grandparents, particularly on the paternal side, are expected to fulfil social obligations to care for left-behind grandchildren, even without immediate financial returns. These suggest that left-behind boys, and in particular boys cared for by paternal grandparents, may be at greater risk than other LBC, as they may receive even fewer resources in the form of remittances from migrant parents in their early childhood
Routine measurement of plasma chromogranin B has limited clinical utility in the management of patients with neuroendocrine tumours
OBJECTIVE: Chromogranin A (CgA) and B (CgB) are markers for monitoring disease status in patients with gastroenteropancreatic neuroendocrine tumours (NETs). These are specialized diagnostic tests often necessitating referral of specimens to a supraregional assay service (SAS) laboratory for analysis. The aim of this audit was to assess whether measurement of either plasma CgA or CgB alone provides sufficient clinical information in comparison with the current practice of measuring both markers together.DESIGN: A retrospective analysis was undertaken for all chromogranin tests requested for patients with a known NET diagnosis. Results were categorized based on whether plasma concentrations were elevated for one or both CgA and CgB.RESULTS: A total of 325 sequential patients with a NET diagnosis had plasma chromogranin levels measured during the period of review. Baseline CgA was elevated in 60·9% of patients. Isolated elevations in CgA (with normal CgB) were found in 44·9% of patients, whilst combined elevations in both CgA and CgB were found in 16% of patients. Combined CgA and CgB concentrations within the normal range were observed for 38·5% of patients. Only two patients (0·6%) had an isolated elevation in CgB at baseline. Both patients had a diagnosis of pancreatic NET and were radiologically stable. Plasma CgA and CgB corresponded with disease stage (localized vs metastatic). CgB in addition to CgA did not provide any significant improvement in diagnostic performance for identification of metastatic disease compared to CgA alone.CONCLUSIONS: Based on this NET population and specific assay performance characteristics, CgA alone provides sufficient information for the management of NET patients; the routine estimation of CgB in all patients is not informative in clinical practice.</p
Pes shape variation in an ornithopod dinosaur trackway (Lower Cretaceous, NW Spain): New evidence of an antalgic gait in the fossil track record.
Trackways can provide unique insight to animals locomotion through quantitative analysis of variation in track morphology. Long trackways additionally permit the study of trackmaker foot anatomy, providing more insight on limb kinematics. In this paper we have restudied the extensive tracksite at Barranco de La Canal-1 (Lower Cretaceous, La Rioja, NW Spain) focussing on a 25-m-long dinosaur (ornithopod) trackway that was noted by an earlier study (Casanovas et al., 1995; Pérez-Lorente, 2003) to display an irregular pace pattern. This asymmetric gait has been quantified and photogrammetric models undertaken for each track, thus revealing distinct differences between the right and the left tracks, particularly in the relative position of the lateral digits II–IV with respect to the central digit III. Given that the substrate at this site is homogenous, the consistent repetition of the collected morphological data suggests that differences recorded between the right and the left tracks can be linked to the foot anatomy, but more interestingly, to an injury or pathology on left digit II. We suggest that the abnormal condition registered in digit II impression of the left pes can be linked to the statistically significant limping behaviour of the trackmaker. Furthermore, the abnormal condition registered did not affect the dinosaur's speed
Sensitivity of Saffman-Taylor fingers to channel-depth perturbations
We examine the sensitivity of Saffman–Taylor fingers to controlled variations in channel depth by investigating the effects of centred, rectangular occlusions in Hele-Shaw channels. For large occlusions, the geometry is known to support symmetric, asymmetric and oscillatory propagation states when air displaces a more viscous fluid from within the channel. A previously developed depth-averaged model is found to be in quantitative agreement with laboratory experiments once the aspect ratio (width/height) of the tube’s cross-section reaches a value of 40. We find that the multiplicity of solutions at finite occlusion heights arises through interactions of the single stable and multiple unstable solutions already present in the absence of the occlusion: the classic Saffman–Taylor viscous fingering problem. The sequence of interactions that occurs with increasing occlusion height is the same for all aspect ratios investigated, but the occlusion height required for each interaction decreases with increasing aspect ratio. Thus, the system becomes more sensitive as the aspect ratio increases in the sense that multiple solutions are provoked for smaller relative depth changes. We estimate that the required depth changes become of the same order as the typical roughnesses of the experimental system ( 1 μm ) for aspect ratios beyond 155, which we conjecture underlies the extreme sensitivity of experiments conducted in such Hele-Shaw channels.<br/
Synovitis and the risk of knee osteoarthritis: the MOST Study.
OBJECTIVE: To identify the independent relation of synovitis with incident radiographic knee osteoarthritis (OA) after adjusting for other structural factors known to cause synovitis. DESIGN: We examined MRIs from knees that developed incident radiographic OA from the Multicenter Osteoarthritis Study (MOST) and compared these case knees with controls that did not develop OA. We examined baseline MRIs for knees developing OA at any time up to 84 months follow-up. We scored lesions in cartilage, meniscus, bone marrow and synovitis. Synovitis scores were summed (0-9) across three regions, suprapatellar, infrapatellar and intercondylar region, each of which was scored 0-3. After bivariate analyses examining each factor's association with incidence, we carried out multivariable regression analyses adjusting for age, sex, BMI, alignment and cartilage and meniscal damage. RESULTS: We studied 239 case and 731 control knees. In bivariate analyses, cartilage lesions, meniscal damage, synovitis and bone marrow lesions were all risk factors for OA. After multivariable analyses, synovitis was associated with incident OA. A higher synovitis score increased the risk of incident OA (adjusted OR per unit increase 1.1; (95% CI 1.0, 1.2, P = .02)), but increased risk was associated only with synovitis scores of ≥3 (adjusted OR 1.6; 95% CI 1.2, 2.1, P = .003). CONCLUSIONS: Synovitis, especially when there is a substantial volume within the knee, is an independent cause of OA