Microwaves enable activated plasma figuring for ultra-precision fabrication of optics

Activated plasma figuring using microwaves aims at providing highly efficient activated energy beams for rapid fabrication of optics. The chemical nature of this type of energy beam leads to targeting silicon-based materials. Furthermore this technology is proposed to address the needs of ultra-precision optical components. In this paper, we present a novel ADTEC microwavegenerated plasma torch design which is operated at atmospheric pressure. In this study, the plasma torch is fed with either argon or helium carrier gas. However this novel design for Plasma Figuring is targeted at local surface correction of crystal quartz which is a material of great interest for optical systems, such as acousto-optic devices. Also this novel design is targeted at reducing midspatial frequency errors such as waviness, ripple errors and residual sub-aperture tool footprints. These are responsible for the scattering of light at small angles, resulting in optical hazing effects, photonic energy loss and pixel cross-talk. Also the results of a preliminary investigation using Optical Emission Spectroscopy (OES) are reported and discussed. These results show the operat ing range when the main processing parameters are changed: microwave forward power values, gas flow rates and the types of gasses

Walkability around primary schools and area deprivation across Scotland

Background: A number of studies based in the US, Canada, and Australia, have found evidence of associations between the built environment (BE) and mode of transport to school, and links between active travel and deprivation. Limited research in the UK compares potential BE supports for walking to school by area deprivation. Within this study, we gathered data on BE attributes previously linked to active travel, i.e., street/path connectivity, and dwelling density, created a composite ‘walkability score’ (WS) for areas around primary schools across urban Scotland, and explored whether poorer areas exhibit lower scores than more affluent areas, or vice versa. We consider this to be a novel approach as few studies have compared BE features by deprivation across a whole country. Methods: Address and road/path maps were obtained and primary schools (N = 937) across mainland Scotland were mapped. Schools were attributed income deprivation scores (scores divided into quintiles (Q1: least deprived, Q5: most deprived)). Catchment area (CA) boundaries, i.e., the geographic area representing eligibility for local school attendance, were drawn around schools, and WS calculated for each CA. We compared mean WS by income quintile (ANOVA), for all local authorities (LAs) combined (N = 29), and separately for the four LAs with the greatest number of schools included in the analysis. Results: For all LAs combined, the least deprived quintile (Q1) showed a significantly lower WS (−0.61), than quintiles 3, 4 and 5 (Q2: −0.04 (non-sig), Q3: 0.38, Q4: 0.09, Q5: 0.18); while for Glasgow the second least deprived quintile (Q2) showed significantly higher WS (Q1: 1.35, Q2: 1.73), than middling (Q3: 0.18) and most deprived quintiles (Q4: 0.06, Q5: −0.10). Conclusion: WS differ by deprivation with patterns varying depending on the spatial scale of the analysis. It is essential that less walkable areas are provided with the resources to improve opportunities to engage in active travel

Out of the pot and into the money: Managing the Western Rock Lobster Fishery by ITE's or ITQ's?

The West Coast Rock Lobster fishery is Australia's most valuable commercial fishery. Around 550 vessels harvest an average of 10,500 tonnes of lobster per annum. The industry has an enviable track record of biological management based on a variety of input controls, although three significant pot reduction interventions have been necessary in recent years. An evaluation of a range of possible future management regimes is reported in this paper. The results were derived from a purpose built bio-economic model three separate biological zones in the fishery using non linear optimization to produce ten year steady state solutions for alternative management options. Management options included the current pot control system, and versions of variable transferable catch quota. Key outputs for each scenario include: net economic benefits, breeder biomass index, annual catch, annual pot lifts, number of pots and vessel numbers. The results indicate significant potential net economic gains from moving away from the current input control regime. The range of scenarios modelled illustrated some of the tradeoffs between maximising net economic returns and minimizing biological risks, as well as quantifying the impact of changes such as improved pot design and extended fishing seasons. The results will inform consideration by the industry about a possible new management system.rock lobster, quotas, ITQs, Western Australia, bioeconomic, economic benefits, Resource /Energy Economics and Policy,

The Lotka Hypothesis And Bibliometric Methodology

This study is an empirical examination of Lotka\u27s law and the bibliometric methodology associated with it. A number of previous investigators have contributed to the empirical validation and generalization of Lotka\u27s hypothesis; however, these studies are largely incomparable and inconclusive, owing to substantial differences in sampling, measurement, parameter estimation, testing, and even basic interpretation of the model. These data are subjected to a consistent secondary analysis here; newly collected data are also analysed, to expand the database of previous results. There are two main objectives in this study: First, to thoroughly and critically review the literature bearing on the statistical modelling of author productivity; and second, to assess these hypotheses, methods, and results against empirical data. The resulting identification and application of efficient parameter estimation procedures within a consistent testing methodology make the implications of earlier validity studies explicit; Lotka\u27s model is found to be surprisingly well-fitting, general and stable, much more so than previously supposed

Physical Activity in Secondary School Pupils: Headline Indicators 2014

In 2013, GoWell East commenced a cohort study of physical activity among secondary school pupils in Glasgow. The study will run from 2013 to 2017, following a group of pupils in six Glasgow secondary schools throughout their school careers from S1 to S5. The study tracks pupils’ participation in physical activity, including sports, as well as other types of activity (including travel to and from school), during their school time and leisure time, during the week and at the weekend. The research is done by asking pupils to complete the Youth Physical Activity Questionnaire (YPAQ)1 .   A group of S5 pupils were also asked to complete the survey in 2013 in order to provide a benchmark with which to compare the S1 study cohort when they reach S5 in 2017

Archaeological field evaluations in Vieux-Aregenua: the benefits of combining geophysical surveys and trial trenches

The Roman city Vieux-Aregenua was already the subject of a pilot test. Magnetometer and electromagnetic induction (EMI) surveys were carried out. The trial trenches of the archaeological field evaluation were strategically placed as to take into account the results of the survey. The surveys allowed definition of the general layout, to characterise the areas and surfaces, and the identification of the buildings. The combined analysis of geophysics and trial trenches permitted the re-examination of the interpretation of geophysical anomalies

The Aversive Effect of Electromagnetic Radiation on Foraging Bats—A Possible Means of Discouraging Bats from Approaching Wind Turbines

Large numbers of bats are killed by collisions with wind turbines and there is at present no accepted method of reducing or preventing this mortality. Following our demonstration that bat activity is reduced in the vicinity of large air traffic control and weather radars, we tested the hypothesis that an electromagnetic signal from a small portable radar can act as a deterrent to foraging bats. From June to September 2007 bat activity was compared at 20 foraging sites in northeast Scotland during experimental trials (radar switched on) and control trials (no radar signal). Starting 45 minutes after sunset, bat activity was recorded for a period of 30 minutes during each trial and the order of trials were alternated between nights. From July to September 2008 aerial insects at 16 of these sites were sampled using two miniature light-suction traps. At each site one of the traps was exposed to a radar signal and the other functioned as a control. Bat activity and foraging effort per unit time were significantly reduced during experimental trials when the radar antenna was fixed to produce a unidirectional signal therefore maximising exposure of foraging bats to the radar beam. However, although bat activity was significantly reduced during such trials, the radar had no significant effect on the abundance of insects captured by the traps

A seven-year retrospective review of colonoscopy records from a single centre in Zambia

IntroductionColorectal disease is common throughout the world, but the spectrum of diagnoses across Africa remains largely unexplored. There is anecdotal evidence of changing colorectal disease but this has not been systematically investigated. The aim of this study was to enhance our insight into the spectrum of colonoscopic diagnoses in Zambia.MethodsWe retrieved written colonoscopy reports from January 2008 to December 2015. Collected data were coded by experienced endoscopists and analysed by age, sex, referral source, indication and diagnosis. ResultsIncluded in this analysis were 573 colonoscopy reports. The most common diagnosis was haemorrhoids (n=151, 26%), followed by tumours (n=96,17%). Over this time period, the proportion of normal colonoscopies decreased by 32% (P<0.001), presumably due to introduction of screening of all requests, while the rate of polyp detection increased from 5% to 10% (P=0.006). The detection of polyps was highest in patients less than 16 years (OR 8.4; 95% CI 2.4-26.2, P<0.001). Of those with colorectal tumours, 33/96 (35%) were less than 45 years although the occurrence was higher with advancing age (P=0.02). Diverticular disease was more common in older age groups (median (IQR) age 70 (60-75) years, versus 47 (34-62) years for those without the disease; P=0.0001).ConclusionThis audit has shown that more than a third of colorectal tumours seen during colonoscopy are in patients below the age of 45 years, with the occurrence of polyps being highest in those below 16 years. Diverticular disease is most common in older age groups