Stamina of a non-gasketed flange joint under combined internal pressure and axial loading

The performance of a bolted flange joint is characterized mainly by its 'strength' and 'sealing capability'. A number of numerical and experimental studies have been conducted to study these characteristics under internal pressure loading conditions alone. However, limited work is found in the literature under conditions of combined internal pressure and axial loading. The effect of external, axial loading pressure being unknown, the optimal performance of the bolted flange joint cannot be achieved. Current design codes do not address the effects of axial loading on structural integrity and sealing ability. To study joint strength and sealing capability under combined loading conditions, an extensive experimental and numerical study of a non-gasketed flange joint was carried out. Actual joint load capacity was determined at both design and test stages with the maximum external axial loading that can be applied for safe joint performance. Experimental and numerical results have been compared and overall joint performance and behaviour is discussed in detail

Finite Element Analysis to model ischemia experienced in the development of device related pressure ulcers.

Pressure ulcers are a common occurrence of damage to skin. Severity ranges from slightly discoloured skin to full thickness tissue damage which can be fatal in some cases. Engineering effort, typically developing computational models had made significant progress in the understanding and demonstration of the formation mechanism of pressure ulcers with the aetiology of excessive stress however relatively limited attempts had been made to develop relevant models for pressure ulcers caused by ischemia. The aim of this paper is to present evidence of a computational model developed to simulate ischemic pressure ulcer formation and demonstrate the established relationship between the computational data and the acquired clinically relevant experimental data by utilising laser Doppler velocimetry. The application of the presented computational model and the established relationship allows the evaluation of the effect of a mechanical loading to the cutaneous blood flow velocity which is a step closing to understand and evaluate a mechanical load to the formation of pressure ulcers caused by ischemia

Pressure relieving support surfaces (PRESSURE) trial : cost effectiveness analysis

Objective To assess tire cost effectiveness of alternating pressure mattresses compared with alternating pressure overlays for the prevention of pressure ulcers in patients admitted to hospital. Design Cost effectiveness analysis carried out alongside the pressure relieving support surfaces (PRESSURE) trial; a multicentre UK based pragmatic randomised controlled trial. Setting 11 hospitals in six UK NHS trusts. Participants Intention to treat population comprising 1971 participants. Main outcome measures Kaplan Meier estimates of restricted mean time to development of pressure ulcers and total costs for treatment in hospital. Results Alternating pressure mattresses were associated with lower overall costs (283.6 pound per patient on average, 95% confidence interval -377.59 pound to. 976.79) pound mainly due to reduced length of stay in hospital, and greater benefits (a delay in time to ulceration of 10.64 days on average, - 24.40 to 3.09). The differences in health benefits and total costs for hospital stay between alternating pressure mattresses and alternating pressure overlays were not statistically significant; however, a cost effectiveness acceptability curve indicated that on average alternating pressure mattresses compared with alternating pressure overlays were associated with air 80% probability of being cost saving. Conclusion Alternating pressure mattresses for the prevention of pressure ulcers are more likely to be cost effective and are more acceptable to patients than alternating pressure overlays

EPUAP classification system for pressure ulcers: European reliability study

‘The definitive version is available at www3.interscience.wiley.com .' Copyright Blackwell PublishingPeer reviewe

Prediction of Primary vs Secondary Hypertension in Children

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91106/1/j.1751-7176.2012.00603.x.pd

The impact of hoist sling materials on interface pressure whilst sitting in healthy volunteers and wheelchair users : a comparative study

Aim of the study To evaluate the effect of three sling fabrics on gluteal interface pressure whilst sitting in a population of wheelchair users and to compare these to data previously collected in a pilot study with a healthy population. Materials and methods A repeated measures experimental design was used with 32 adult wheelchair users (15 women, 17 men). Healthy population pilot study consisted of 61 participants (51 women, 10 men) recruited from staff and students at The University of Salford. Methods Gluteal pressures at six pressure zones were recorded using the X-sensor PX100 pressure sensor at 30 second intervals for 10 minutes. Data were collected in 4 conditions with participants seated in a standardised chair, followed by the chair with slings made of three different fabrics. Results The spacer fabric reduced the mean gluteal pressure more effectively than slipfit and polyester (p=0.014 and p=0.01 respectively, 95%CI) and reduced peak pressure at the left ischial tuberosity and coccyx when compared to the slipfit (p=0.003 and p=0.005) with the wheelchair users. When comparing data with the pilot study, the mean gluteal pressure and peak pressures at the ischial tuberosities and coccyx were significantly higher in the wheelchair user group (p<0.005). Conclusion The fabric identified as the most effective in reducing mean and peak pressures in both groups was the spacer fabric, suggesting that a spacer fabric sling is more likely to reduce the risk of pressure ulcer development. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors

The triglyceride to high-density lipoprotein ratio identifies children who may be at risk of developing cardiometabolic disease

Aim: It is important to develop simple, reliable methods to identify high-risk individuals who may benefit from intervention. This study investigated the association between the triglyceride to high-density lipoprotein cholesterol (TG/HDL) ratio and cardiometabolic risk, cardiorespiratory fitness and physical activity in children. Methods: Anthropometric, biochemical parameters, cardiorespiratory fitness and accelerometry determined physical activity were assessed in 155 children (80 girls) from 10 to 14 years of age from Bedfordshire, UK. Participants were grouped into high and low TG/HDL ratio groups, according to published thresholds. MANCOVA and logistic regression were used in the analysis. Results: Cardiometabolic risk factor levels were significantly higher in participants with a high TG/HDL ratio (p < 0.05). The odds of having high waist circumference (OR = 13.99; 95% CI 2.93, 69.25), elevated systolic blood pressure (5.27; 1.39, 20.01), high non-HDL cholesterol (19.47; 4.42, 85.81) and ≥2 cardiometabolic risk factors (15.32; 3.10, 75.79) were higher in participants with a high TG/HDL ratio. The TG/HDL ratio values were significantly lower in those with high cardiorespiratory fitness (p = 0.01), but there was no association with physical activity. Conclusion: These findings support the use of the TG/HDL ratio to identify children with cardiometabolic risk factors who may be at risk of developing cardiometabolic disease

Occupational and leisure time physical activity in contrasting relation to ambulatory blood pressure

Background: While moderate and vigorous leisure time physical activities are well documented to decrease the risk for cardiovascular disease, several studies have demonstrated an increased risk for cardiovascular disease in workers with high occupational activity. Research on the underlying causes to the contrasting effects of occupational and leisure time physical activity on cardiovascular health is lacking. The aim of this study was to examine the relation of objective and self-report measures of occupational and leisure time physical activity with 24-h ambulatory systolic blood pressure (BP). Methods: Results for self-reported physical activity are based on observations in 182 workers (60% male, mean age 51 years), while valid objective physical activity data were available in 151 participants. The usual level of physical activity was assessed by 5 items from the Job Content Questionnaire (high physical effort, lifting heavy loads, rapid physical activity, awkward body positions and awkward positions of head or arms at work) and one item asking about the general level of physical activity during non-working time. On a regular working day, participants wore an ambulatory BP monitor and an accelerometer physical activity monitor during 24 h. Associations were examined by means of Analysis of Covariance. Results: Workers with an overall high level of self-reported occupational physical activity as well as those who reported to often lift heavy loads at work had a higher mean systolic BP at work, at home and during sleep. However, no associations were observed between objectively measured occupational physical activity and BP. In contrast, those with objectively measured high proportion of moderate and vigorous leisure time physical activity had a significantly lower mean systolic BP during daytime, while no differences were observed according to self-reported level of leisure time physical activity. Conclusions: These findings suggest that workers reporting static occupational physical activities, unlike general physically demanding tasks characterized by dynamic movements of large muscle groups, are related to a higher daily systolic BP, while high objective levels of moderate and vigorous leisure time physical activity are related to lower daytime systolic BP. Ambulatory systolic BP may be a physiological explanatory factor for the contrasting effects of occupational and leisure time physical activity

Apolipoprotein L1 gene variants associate with prevalent kidney but not prevalent cardiovascular disease in the Systolic Blood Pressure Intervention Trial.

Apolipoprotein L1 gene (APOL1) G1 and G2 coding variants are strongly associated with chronic kidney disease (CKD) in African Americans (AAs). Here APOL1 association was tested with baseline estimated glomerular filtration rate (eGFR), urine albumin:creatinine ratio (UACR), and prevalent cardiovascular disease (CVD) in 2571 AAs from the Systolic Blood Pressure Intervention Trial (SPRINT), a trial assessing effects of systolic blood pressure reduction on renal and CVD outcomes. Logistic regression models that adjusted for potentially important confounders tested for association between APOL1 risk variants and baseline clinical CVD (myocardial infarction, coronary, or carotid artery revascularization) and CKD (eGFR under 60 ml/min per 1.73 m(2) and/or UACR over 30 mg/g). AA SPRINT participants were 45.3% female with a mean (median) age of 64.3 (63) years, mean arterial pressure 100.7 (100) mm Hg, eGFR 76.3 (77.1) ml/min per 1.73 m(2), and UACR 49.9 (9.2) mg/g, and 8.2% had clinical CVD. APOL1 (recessive inheritance) was positively associated with CKD (odds ratio 1.37, 95% confidence interval 1.08-1.73) and log UACR estimated slope (β) 0.33) and negatively associated with eGFR (β -3.58), all significant. APOL1 risk variants were not significantly associated with prevalent CVD (1.02, 0.82-1.27). Thus, SPRINT data show that APOL1 risk variants are associated with mild CKD but not with prevalent CVD in AAs with a UACR under 1000 mg/g