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Nonintrusive Estimation of Anisotropic Stiffness Maps of Heterogeneous Steel Welds for the Improvement of Ultrasonic Array Inspection
No full textIt is challenging to inspect austenitic welds non-destructively using ultrasonic waves because the spatially varying elastic anisotropy of weld microstructures can lead to the deviation of ultrasound. Models have been developed to predict the propagation of ultrasound in such welds once the weld stiffness heterogeneity is known. Consequently, it is desirable to have a means of measuring the variation in elastic anisotropy experimentally so as to be able to correct for deviations in ultrasonic pathways for the improvement of weld inspection. This paper investigates the use of external nonintrusive ultrasonic array measurements to construct such weld stiffness maps, representing the orientation of the stiffness tensor according to location in the weld cross section. An inverse model based on a genetic algorithm has been developed to recover a small number of key parameters in an approximate model of the weld map, making use of ultrasonic array measurements. The approximate model of the weld map uses the Modeling of anIsotropy based on Notebook of Arcwelding (MINA) formulation, which is one of the representations that has been proposed by other researchers to provide a simple, yet physically based, description of the overall variations of orientations of the stiffness tensors over the weld cross section. The choice of sensitive ultrasonic modes as well as the best monitoring positions have been discussed to achieve a robust inversion. Experiments have been carried out on a 60-mm-thick multipass tungsten inert gas (TIG) weld to validate the findings of the modeling, showing very good agreement. This work shows that ultrasonic array measurements can be used on a single side of a butt-welded plate, such that there is no need to access the remote side, to construct an approximate but useful weld map of the spatial variations in anisotropic stiffness orientation that occur within the weld
Examining variations in prescribing safety in UK general practice: cross sectional study using the Clinical Practice Research Datalink.
No full textSTUDY QUESTION: What is the prevalence of different types of potentially hazardous prescribing in general practice in the United Kingdom, and what is the variation between practices? METHODS: A cross sectional study included all adult patients potentially at risk of a prescribing or monitoring error defined by a combination of diagnoses and prescriptions in 526 general practices contributing to the Clinical Practice Research Datalink (CPRD) up to 1 April 2013. Primary outcomes were the prevalence of potentially hazardous prescriptions of anticoagulants, anti-platelets, NSAIDs, β blockers, glitazones, metformin, digoxin, antipsychotics, combined hormonal contraceptives, and oestrogens and monitoring by blood test less frequently than recommended for patients with repeated prescriptions of angiotensin converting enzyme inhibitors and loop diuretics, amiodarone, methotrexate, lithium, or warfarin. STUDY ANSWER AND LIMITATIONS: 49 927 of 949 552 patients at risk triggered at least one prescribing indicator (5.26%, 95% confidence interval 5.21% to 5.30%) and 21 501 of 182 721 (11.8%, 11.6% to 11.9%) triggered at least one monitoring indicator. The prevalence of different types of potentially hazardous prescribing ranged from almost zero to 10.2%, and for inadequate monitoring ranged from 10.4% to 41.9%. Older patients and those prescribed multiple repeat medications had significantly higher risks of triggering a prescribing indicator whereas younger patients with fewer repeat prescriptions had significantly higher risk of triggering a monitoring indicator. There was high variation between practices for some indicators. Though prescribing safety indicators describe prescribing patterns that can increase the risk of harm to the patient and should generally be avoided, there will always be exceptions where the indicator is clinically justified. Furthermore there is the possibility that some information is not captured by CPRD for some practices-for example, INR results in patients receiving warfarin. WHAT THIS STUDY ADDS: The high prevalence for certain indicators emphasises existing prescribing risks and the need for their appropriate consideration within primary care, particularly for older patients and those taking multiple medications. The high variation between practices indicates potential for improvement through targeted practice level intervention. FUNDING, COMPETING INTERESTS, DATA SHARING: National Institute for Health Research through the Greater Manchester Primary Care Patient Safety Translational Research Centre (grant No GMPSTRC-2012-1). Data from CPRD cannot be shared because of licensing restrictions
Human hair follicle epithelial stem cells undergo epithelial-mesenchymal transition (EMT) in primary cicatricial alopecia: Lessons from lichen planopilaris
No full textDevelopment and Evaluation of an Intervention to Support Family Caregivers of People with Cancer to Provide Home-based Care at the End of Life: a Feasibility Study
No full textPurpose To design and evaluate an intervention to address carers’ needs for practical information and support skills when caring for a person with cancer at end of life. Method Phase I 29 carers were interviewed about need for practical information, support skills and their preferences for information delivery. The preferred format was a booklet. Phase 2 evaluated the booklet. 31 carers and 14 district nurses participated. Validated questionnaires: on perceptions of caregiving and carer health before and after the booklet was used and interviews with both carers and nurses were untertaken.24 carers completed both interviews. Quantitative data were coded using scale manuals and analysed using SPSSv20 and interview data was analysed thematically. Results: Carers were aged 31-82 and cared for people aged 50-92; 8 carers were male and 23 female; 20 cared for a partner, 8 for a parent and 1 for a sibling (2 undisclosed). Carers were positive about the booklet, however many carers would have liked the booklet earlier. Carers reported feeling more positive about caregiving, and more reassured and competent in their role. District nurses found the booklet useful and reported receiving fewer phone calls from study carers than others in similar situations. Conclusions: The booklet intervention was a source of reassurance to carers and it has the potential to be incorporated into everyday practice. The challenge is in when and how to distribute the booklet and more work is required on the timing of delivery in order to maximise the usefulness of booklet to carers
Distribution of Bioactive Lipid Mediators in Human Skin
No full textThe skin produces bioactive lipids that participate in physiological and pathological states, including homeostasis, induction, propagation, and resolution of inflammation. However, comprehension of the cutaneous lipid complement, and contribution to differing roles of the epidermal and dermal compartments, remains incomplete. We assessed the profiles of eicosanoids, endocannabinoids, N-acyl ethanolamides, and sphingolipids, in human dermis, epidermis, and suction blister fluid. We identified 18 prostanoids, 12 hydroxy-fatty acids, 9 endocannabinoids and N-acyl ethanolamides, and 21 non-hydroxylated ceramides and sphingoid bases, several demonstrating significantly different expression in the tissues assayed. The array of dermal and epidermal fatty acids was reflected in the lipid mediators produced, whereas similarities between lipid profiles in blister fluid and epidermis indicated a primarily epidermal origin of suction blister fluid. Supplementation with omega-3 fatty acids ex vivo showed that their action is mediated through perturbation of existing species and formation of other anti-inflammatory lipids. These findings demonstrate the diversity of lipid mediators involved in maintaining tissue homeostasis in resting skin and hint at their contribution to signaling, cross-support, and functions of different skin compartments. Profiling lipid mediators in biopsies and suction blister fluid can support studies investigating cutaneous inflammatory responses, dietary manipulation, and skin diseases lacking biomarkers and therapeutic targets
Corrosion behaviour of stainless steel–titanium alloy linear friction welded joints:Galvanic coupling
No full textLongitudinal predictors of subjective recovery in psychosis
No full textBackground: Research has highlighted the importance of recovery as defined by the service user, and suggests a link to negative emotion, although little is known about the role of negative emotion in predicting subjective recovery. Aims: To investigate longitudinal predictors of variability in recovery scores with a focus on the role of negative emotion. Method: Participants (n=110) with experience of psychosis completed measures of psychiatric symptoms, social functioning, subjective recovery, depression, hopelessness and selfesteem at baseline and 6 months later. Path analysis was used to examine predictive factors for recovery and negative emotion. Results: Subjective recovery scores were predicted by negative emotion, positive self-esteem and hopelessness, and to a lesser extent by symptoms and functioning. Current recovery score was not predicted by past recovery score after accounting for past symptoms, current hopelessness and current positive self-esteem. Conclusions: Psychosocial factors and negative emotion appear to be the strongest longitudinal predictors of variation in subjective recovery, rather than psychiatric symptoms
Colonization of the Mediterranean Basin by the vector biting midge species Culicoides imicola: an old story.
No full textUnderstanding the demographic history and genetic make-up of colonizing species is critical for inferring population sources and colonization routes. This is of main interest for designing accurate control measures in areas newly colonized by vector species of economically important pathogens. The biting midge Culicoides imicola is a major vector of Orbiviruses to livestock. Historically, the distribution of this species was limited to the Afrotropical region. Entomological surveys first revealed the presence of C. imicola in the south of the Mediterranean basin by the 1970's. Following recurrent reports of massive bluetongue outbreaks since the 1990s, the presence of the species was confirmed in northern areas. In this study, we addressed the chronology and processes of C. imicola colonization in the Mediterranean basin. We characterized the genetic structure of its populations across Mediterranean and African regions using both mitochondrial and nuclear markers, and combined phylogeographical analyses with population genetics and approximate Bayesian computation. We found a west/east genetic differentiation between populations, occurring both within Africa and within the Mediterranean basin. We demonstrated that three of these groups had experienced demographic expansions in the Pleistocene, probably because of climate changes during this period. Finally, we showed that C. imicola could have colonized the Mediterranean basin in the late Pleistocene or early Holocene through a single event of introduction; however we cannot exclude the hypothesis involving two routes of colonization. Thus, the recent bluetongue outbreaks are not linked to C. imicola colonization event, but rather to biological changes in the vector or the virus. This article is protected by copyright. All rights reserved
Bangladeshi women's experiences of infant feeding in the London Borough of Tower Hamlets
No full textThis study examined the main factors that influence Bangladeshi women living in London's decisions to partially breastfeed their children, including the influence of older women within the community. Fifty-seven women of Bangladeshi origin living in the London Borough of Tower Hamlets took part in seven discussion groups between April and June 2013. Five groups were held with women of child-bearing age and two groups with older women in the community. A further eight younger women and three older women took part in one-on-one interviews. Interviews were also carried out with eight local health care workers, including public health specialists, peer support workers, breastfeeding coordinators and a health visitor. The influences on women's infant feeding choices can be understood through a ˜socio-ecological model", including public health policy; diverse cultural influences from Bangladesh, London and the Bangladeshi community in London; and the impacts of migration and religious and family beliefs. The women's commitment to breastfeeding was mediated through the complexity of their everyday lives. The tension between what was ˜best" and what was ˜possible" leads them not only to partially breastfeed but also to sustain partial breastfeeding in a way not seen in other socio-cultural groups in the United Kingdom