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With many Tidal Energy Conversion (TEC) devices at full scale prototype stage there are two distinct design groups for Horizontal Axis Tidal Turbines (HATTs). Devices with a yaw mechanism allowing the turbine to always face into the flow, and devices with blades that can rotate through 180° to harness a strongly bi-directional flow. As marine turbine technology verges on the realm of economic viability this paper reveals the performance of Cardiff University's concept tidal turbine with its support structure either upstream or downstream and with various proximities between the rotating plane of the turbine and its support stanchion. Through the use of validated Computational Fluid Dynamics (CFD) modelling this work shows the optimal proximity between rotor plane and stanchion as well as establishing, in the given context, the use of a yaw mechanism to be superior to a bi-directional system from a performance perspective. [ABSTRACT FROM AUTHOR]

Flexible perovskite solar cells feature high power-per-weight ratio and low cost manufacturing, which make them very attractive for space and avionic applications. It is thus paramount to assess their response to the harsh space environment. Although an increasing number of studies have been investigating the effect of electron and proton radiation on perovskite solar cells, very few have dealt with neutron irradiation and even less with flexible devices. In this paper, the stability of unencapsulated flexible perovskite solar cells against fast neutron irradiation at two different fluence levels is evaluated, comparing commercially available spiro-OMeTAD and an in-house modified P3HT as the hole transport materials. We observed degradation for both materials and at both fluences. Modified-P3HT cells experienced remarkable smaller voltage and current losses compared to spiro-OMeTAD; still, their overall performance degraded similarly to spiro-OMeTAD devices at higher fluence, whilst it suffered a much higher drop than spiro-OMeTAD at lower fluence, as a consequence of a larger decrease in fill factor, ascribable to a sub-optimal perovskite/polymer interface. Spectral response and behavior at different light intensities of modified-P3HT cells suggest the polymer to be potentially more resilient than spiro-OMeTAD under fast neutron irradiation, once the perovskite/polymer is improved, although further investigations are needed to gain more insights and push the development and adoption of flexible PSCs for space and avionic applications. [Display omitted] • Unencapsulated flexible perovskite solar cells were irradiated with fast neutrons. • Effect of the irradiation was evaluated on both spiro-OMeTAD and modified-P3HT cells. • All flexible perovskite solar cells experienced irradiation-induced degradation. • Modified P3HT is potentially more resilient to fast neutrons than spiro-OMeTAD, although further investigation is needed. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effect of an organic cannabis extract on β-cell secretory function in an in vivo diet-induced obese rat model and determine the associated molecular changes within pancreatic tissue. Diet-induced obese Wistar rats and rats fed on standard pellets were subcutaneously injected with an organic cannabis extract or the vehicle over a 28-day period. The effect of diet and treatment was evaluated using the intraperitoneal glucose tolerance tests (IPGTTs) and qPCR analysis on rat pancreata harvested upon termination of the experiment. The cafeteria diet induced an average weight difference of 32g and an overall increase in body weight in the experimental groups occurred at a significantly slower rate than the control groups, irrespective of diet. Area under the curve for glucose (AUC(g)) in the obese group was significantly lower compared to the lean group (p<0.001), with cannabis treatment significantly reducing the AUC(g) in the lean group (p<0.05), and remained unchanged in the obese group, relative to the obese control group. qPCR analysis showed that the cafeteria diet induced down-regulation of the following genes in the obese control group, relative to lean controls: UCP2, c-MYC and FLIP. Cannabis treatment in the obese group resulted in up-regulation of CB1, GLUT2, UCP2 and PKB, relative to the obese control group, while c-MYC levels were down-regulated, relative to the lean control group. Treatment did not significantly change gene expression in the lean group. These results suggest that the cannabis extract protects pancreatic islets against the negative effects of obesity. [ABSTRACT FROM AUTHOR]

Aim: To evaluate major/minor discrepancy rates for provisional (initial) and addendum (supplementary senior review) emergency computed tomography (CT) reports in patients presenting with non-traumatic abdominal pain.Materials and Methods: Ethical approval for this type of study is not required in the UK. All radiology departments with an approved lead for audit registered with the Royal College of Radiologists were invited to participate in this retrospective audit. The first 50 consecutive patients (25 surgical, 25 non-surgical) who underwent emergency abdominal CT for non-traumatic abdominal pain in 2013 were included. Statistical analyses were performed to identify organisational and report/patient-related variables that might be associated with major discrepancy.Results: One hundred and nine (58%) of 188 departments supplied data to the study with a total of 4,931 patients (2,568 surgical, 2,363 non-surgical). The audit standard for provisional report major discrepancy was achieved for registrars (target <10%, achieved 4.6%), for on-site consultants (target <5%, achieved 3.1%) and consultant addendum (target <5%, achieved 2.9%). Off-site reporters failed to meet the standard target (<5%, achieved 8.7% overall and 12.7% in surgical patients). The standard for patients coming to harm was not met in the surgical group (target <1%, achieved 1.5%) and was narrowly missed overall (target <1%, achieved 1%).Conclusion: This study should be used to provide impetus to improve aspects of out-of-hours CT reporting. Clear benefits of CT interpretation/review by on-site and more senior (consultant) radiologists have been demonstrated. [ABSTRACT FROM AUTHOR]

Aim: To report the results of a nationwide audit of the accuracy of magnetic resonance imaging (MRI) staging in uterine body cancer when staging myometrial invasion, cervical extension, and lymph node spread. Materials and methods: All UK radiology departments were invited to participate using a web-based tool for submitting anonymized data for a 12 month period. MRI staging was compared with histopathological staging using target accuracies of 85, 86, and 70% respectively. Results: Of the departments performing MRI staging of endometrial cancer, 37/87 departments contributed. Targets for MRI staging were achieved for two of the three standards nationally with diagnostic accuracy for depth of myometrial invasion, 82%; for cervical extension, 90%; and for pelvic nodal involvement, 94%; the latter two being well above the targets. However, only 13/37 (35%) of individual centres met the target for assessing depth of myometrial invasion, 31/36 (86%) for cervical extension and 31/34 (91%) for pelvic nodal involvement. Statistical analysis demonstrated no significant difference for the use of intravenous contrast medium, but did show some evidence of increasing accuracy in assessment of depth of myometrial invasion with increasing caseload. Conclusion: Overall performance in the UK was good, with only the target for assessment of depth of myometrial invasion not being met. Inter-departmental variation was seen. One factor that may improve performance in assessment of myometrial invasion is a higher caseload. No other clear factor to improve performance were identified. [Copyright &y& Elsevier]

Abstract: We measured hippocampi on baseline-, 6- and 12-month scans in a group of AD (n =36) and control subjects (n =20). We found that mean annualised atrophy rates using 6-month intervals were comparable at a group level to those generated from a 12-month interval. Higher variance was seen using shorter intervals, although this was only significant in the control group. This has implications where shorter inter-scan intervals may be advantageous, such as rapid diagnosis, and tracking of disease progression including in a clinical trial. [Copyright &y& Elsevier]

Abstract: Alzheimer''s disease (AD) is associated with excess whole brain volume loss, and progressive cognitive impairment. We aimed to study the extent to which these two potential biomarkers of AD progression are correlated. Forty-six patients with sporadic AD were tested with a neuropsychometric battery including test of verbal and visual memory, vocabulary, arithmetic, naming, visuoperceptual skills and reasoning at two time-points, approximately 1 year apart; annualised rates of change for each test were calculated. Each subject also attended for up to twelve T1-weighted volumetric MRI scans at fixed intervals over a 2-year period. For each individual all possible scan-pairs were positionally registered, and whole brain atrophy rates were calculated using the brain boundary shift integral. Linear mixed models were used to investigate associations between atrophy rate and coincident change in each neuropsychometric score. Each model estimated the effect of a unit change in score, plus the additional effect of a fall to floor, after adjusting for baseline levels. 467 MRI scans were performed, permitting 2199 individual measures of change to be made. The model-derived mean atrophy rate was 2.23% per year with a between-subject SD of 0.99% per year. Increasing atrophy rate was significantly associated with rate of change in a number of non-memory based neuropsychological scores, with the strongest association seen with longitudinal change in matrix reasoning (p =0.004). These results provide further evidence that cerebral atrophy is a clinically relevant marker of AD progression. This methodology whereby data from patients falling to floor on a given test may be included and accounted for, rather than discarded, may find broader application in clinical studies incorporating neuropsychometric outcomes. [Copyright &y& Elsevier]

Purpose: To examine the relation between green tea consumption and serum lipids and lipoproteins.Methods: The subjects were 13,916 workers (8476 men and 5440 women) aged 40-69 years at over 1000 workplaces in Nagano prefecture, central Japan. They underwent health screening offered by a single medical institute between April 1995 and March 1996 and did not have morbid conditions affecting serum cholesterol levels. Serum concentrations of total cholesterol, high-density lipoprotein (HDL) cholesterol and triglycerides were measured at the screening. The consumption of green tea and other life-style characteristics were ascertained by a questionnaire. The data were analyzed with multivariate linear model.Results: Daily consumption of green tea was reported by 86.7% of subjects. Green tea consumption was, statistically, significantly associated with lower levels of serum total cholesterol in both men and women while its associations with serum triglycerides and HDL cholesterol were not statistically significant. The inverse association of serum total cholesterol with green tea consumption appeared to level off at the consumption of more than 10 cups/day. Excluding the outlying subjects drinking more than 10 cups/day (0.4%), the regression analysis adjusting for age, body mass index, ethanol intake, smoking habit, coffee intake, and type of work showed that daily consumption of one cup of green tea was associated with a reduction in serum total cholesterol by 0.015 mmol/L (95% confidence interval 0.006 to 0.024, p < 0.001) in men and 0.015 mmol/L (0.004 to 0.025, p < 0.01) in women. After additional adjustment for selected dietary factors, the inverse association remained statistically significant; one cup of green tea per day was associated with a reduction in serum total cholesterol by 0.010 mmol/L (0.001 to 0.019, p = 0.03) in men and 0.012 mmol/L (0.001 to 0.022, p = 0.03) in women.Conclusion: Consumption of green tea was associated with lower serum concentration of total cholesterol in Japanese healthy workers age 40-69 years; however, green tea consumption was unrelated to serum HDL-cholesterol and triglycerides. [ABSTRACT FROM AUTHOR]

Lunar regolith simulant is exposed to a fast neutron flux of a spallation source. The samples consisted of a set of as-received, traditionally sintered, and solar sintered JSC-2A lunar regolith simulant. Aluminium samples were also irradiated for comparison. The ChipIr beamline of the ISIS neutron and muon source was used to provide a flux of atmospheric-like neutrons. The shielding properties of the different samples were measured for transmission, by counting neutrons before and after the samples using fast neutron detectors. Monte-Carlo simulations were carried out concurrently. The simulations are in good agreement with measurements. Aluminium simulations have shown to be in better accordance with the experimental results, probably because less affected by systematic errors. As for regolith shielding, a sensitivity analysis showed the low impact of the variations in regolith composition on the shielding properties. The benchmark of the simulations has allowed an independent estimate of the required level of regolith shielding needed to cope with primary and secondary radiation emissions. For galactic cosmic rays a value > 200 g/cm2 is estimated to give >50% reduction in transmission. For solar particle events a few 10s of g/cm2 can reduce the dose by more than an order of magnitude. • Lunar regolith simulants were exposed to a fast neutron flux. • Monte-Carlo simulations were carried out concurrently. • Shielding capability of lunar regolith were measured and discussed. • For GCRs a value > 200 g/cm2 is estimated to give >50% reduction in transmission. • For SPE a few 10s of g/cm2 can reduce the dose by more than an order of magnitude. [ABSTRACT FROM AUTHOR]

This work investigates the effects of aging and voltage scaling in neutron-induced bit-flip in SRAM-based Field Programmable Gate Array (FPGA). Experimental results show that aging and voltage scaling can increase in at least two times the susceptibility of SRAM-based FPGAs to Soft Error Rate (SER). These results are innovative, because they combine three real effects that occur in programmable circuits operating at ground-level applications. In addition, a model at electrical level for aging, soft error and different voltages in SRAM memory cells was described to investigate by simulation in more details the effects observed at the practical neutron irradiation experiment. Results can guide designers to predict soft error effects during the lifetime of devices operating in different power supply mode. [ABSTRACT FROM AUTHOR]

An abstract of the article "Making the New Sodium School Meal Standards Work in Your Community: Lessons Learned from the Field" by Andrea Anater is presented.

Abstract: Background: MRI in presymptomatic autosomal dominant Alzheimer''s disease mutation carriers (MC) provides an opportunity to detect changes that pre-date symptoms or clinical diagnosis. We used automated cortical thickness (CTh) measurement to compare the grey matter of such a group with cognitively normal controls. Methods: 9 presymptomatic mutation carriers (4 PSEN1, 5 APP) and 25 healthy, age and sex-matched controls underwent longitudinal volumetric MRI brain imaging. CTh measurement was performed across the whole brain using a validated, automated technique. Four regions of interest (ROI) (entorhinal cortex (ERC), parahippocampal gyrus (PHG), posterior cingulate cortex and precuneus) and two control regions (paracentral and pericalcarine) were selected on the basis of imaging data in existing Alzheimer''s disease (AD) literature. Linear mixed models were used to describe normal ageing in controls and the extent to which mean CTh in cases differed from controls according to time since clinical diagnosis, adjusting for normal ageing. Results: An accelerating decline in CTh was observed across all ROI in the MC group. No such decline was demonstrated in the control regions for the MC group. Relative to controls, and adjusting for normal ageing, there was evidence (p =0.05, one-sided test) of lower CTh in the posterior cingulate up to 1.8 years prior to diagnosis and in the precuneus up to 4.1 years prior to diagnosis in the MC group. Discussion: Automated CTh analysis is a relatively practical, rapid and effective technique for assessing subtle structural change in AD. There is evidence that cortical thickness is reduced in mutation carriers a number of years prior to clinical diagnosis. [Copyright &y& Elsevier]

Abstract: Six selected diketopiperazines, cyclo(Gly-Val), cyclo(Gly-D-Val), cyclo(Gly-Leu), cyclo(Gly-Ile), cyclo(Phe-Cys) and cyclo(Tyr-Cys), were synthesized via various synthetic routes. Their potential to inhibit cancer cell growth in HT-29, HeLa and MCF-7 cells was determined. Cyclo(Tyr-Cys) caused the greatest inhibition in cervical carcinoma cells with near equivalent activity against HT-29 and MCF-7 cells. The other cyclic dipeptides tested were effective in the inhibition of colon, cervical and breast carcinoma cells, respectively, but the percentage inhibition was lower than for cyclo(Tyr-Cys). [Copyright &y& Elsevier]

Abstract: We describe a method of automatically calculating hippocampal atrophy rates on T1-weighted MR images without manual delineation of hippocampi. This method was applied to a group of Alzheimer''s disease (AD) (n =36) and control (n =19) subjects and compared with manual methods (manual segmentation of baseline and repeat-image hippocampi) and semi-automated methods (manual segmentation of baseline hippocampi only). In controls, mean (S.D.) atrophy rates for manual, semi-automated, and automated methods were 18.1 (53.5), 15.3 (50.2) and 11.3 (50.4)mm3 loss per year, respectively. In AD patients these rates were 174.6 (106.5) 159.4 (101.2) and 172.1 (123.1)mm3 loss per year, respectively. The automated method was a significant predictor of disease (p =0.001) and gave similar group discrimination compared with both semi-automated and manual methods. The automated hippocampal analysis in this small study took approximately 20min per hippocampal pair on a 3.4GHz Intel Xeon server, whereas manual delineation of each hippocampal pair took approximately 90min of operator-intensive labour. This method may be useful diagnostically or in studies where analysis of many scans may be required. [Copyright &y& Elsevier]

An abstract of the presentation "Lessons Learned from Planning and Implementing Sodium Reduction Strategies with Independent Restaurants" by Karen Strazza and colleagues is presented.