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A total of 592 people reported gastrointestinal illness following attendance at Street Spice, a food festival held in Newcastle-upon-Tyne, North East England in February/March 2013. Epidemiological, microbiological and environmental investigations were undertaken to identify the source and prevent further cases. Several epidemiological analyses were conducted; a cohort study; a follow-up survey of cases and capture re-capture to estimate the true burden of cases. Indistinguishable isolates of Salmonella Agona phage type 40 were identified in cases and on fresh curry leaves used in one of the accompaniments served at the event. Molecular testing indicated entero-aggregative Escherichia coli and Shigella also contributed to the burden of illness. Analytical studies found strong associations between illness and eating food from a particular stall and with food items including coconut chutney which contained fresh curry leaves. Further investigation of the food supply chain and food preparation techniques identified a lack of clear instruction on the use of fresh uncooked curry leaves in finished dishes and uncertainty about their status as a ready-to-eat product. We describe the investigation of one of the largest outbreaks of food poisoning in England, involving several gastrointestinal pathogens including a strain of Salmonella Agona not previously seen in the UK.
Monolithic integrated thin film tandem solar cells consisting of a high bandgap perovskite top cell and a low bandgap thin film bottom cell are expected to reach higher power conversion efficiencies (PCEs) with lower manufacturing cost and environmental impacts than the market-dominant crystalline silicon photovoltaics. There have been several demonstrations of 4-terminal and 2-terminal perovskite tandem devices with CuInGaSe2 (CIGS) or CuInSe2 (CIS) and, similar to the other tandem structures, the optimization of this device relies on optimal choice for the perovskite bandgap and thickness. Therefore, further advancement will be enabled by tuning the perovskite absorber to maximize the photocurrent limited by the current match condition. Here, we systematically study the optical absorption and transmission of perovskite thin films with varying absorber band gap. Based on these results, we model the photocurrent generations in both perovskite and CIS subcells and estimate the performances of projected tandem devices by considering the ideally functioning perovskite and CIS device. Our results show that for perovskite layers with 500 nm thickness the optimal bandgap is around 1.6 eV. With these configurations, PCEs above 20% could be achieved by monolithically integrated perovskite/CIS tandem solar cells. Also by modelling the absorption at every layer we calculate the quantum efficiency at each subcell in addition to tracking optical losses.
Strategies for the involvement of primary care in the management of patients with presumed or diagnosed dementia are heterogeneous across Europe. We wanted to explore attitudes of primary care physicians (PCPs) when managing dementia: (i) the most popular cognitive tests, (ii) who had the right to initiate or continue cholinesterase inhibitor or memantine treatment, and (iii) the relationship between the permissiveness of these rules/guidelines and PCP's approach in the dementia investigations and assessment.
Key informant survey. Setting: Primary care practices across 25 European countries. Subjects: Four hundred forty-five PCPs responded to a self-administered questionnaire. Two-step cluster analysis was performed using characteristics of the informants and the responses to the survey. Main outcome measures: Two by two contingency tables with odds ratios and 95% confidence intervals were used to assess the association between categorical variables. A multinomial logistic regression model was used to assess the association of multiple variables (age class, gender, and perceived prescription rules) with the PCPs’ attitude of “trying to establish a diagnosis of dementia on their own.”
Discrepancies between rules/guidelines and attitudes to dementia management was found in many countries. There was a strong association between the authorization to prescribe dementia drugs and pursuing dementia diagnostic work-up (odds ratio, 3.45; 95% CI 2.28–5.23).
Differing regulations about who does what in dementia management seemed to affect PCP's engagement in dementia investigations and assessment. PCPs who were allowed to prescribe dementia drugs also claimed higher engagement in dementia work-up than PCPs who were not allowed to prescribe.
As part of a program to study surge-type glaciers, a radar-depth survey, using a frequency of 620 MHz, has been made of Trapridge Glacier, Yukon Territory. Soundings were taken at 26 locations on the glacier surface and a maximum ice thickness of 143 m was measured. A rapid change in surface slope in the lower ablation region marks the boundary between active and stagnant ice and is suggestive of an “ice dam” or the water “collection zone” postulated by Robin and Weertman for surging glaciers.
Objectives: The aim of this study was to describe cognitive, academic, and psychosocial outcomes after an incident demyelinating event (acquired demyelinating syndromes, ADS) in childhood and to investigate the contribution of brain lesions and confirmed MS diagnosis on outcome. Methods: Thirty-six patients with ADS (mean age=12.2 years, SD=2.7, range: 7–16 years) underwent brain MRI scans at presentation and at 6-months follow-up. T2-weighted lesions on MRI were assessed using a binary classification. At 6-months follow-up, patients underwent neuropsychological evaluation and were compared with 42 healthy controls. Results: Cognitive, academic, and behavioral outcomes did not differ between the patients with ADS and controls. Three of 36 patients (8.3%) were identified with cognitive impairment, as determined by performance falling ≤1.5 SD below normative values on more than four independent tests in the battery. Poor performance on a visuomotor integration task was most common, observed among 6/32 patients, but this did not differ significantly from controls. Twelve of 36 patients received a diagnosis of MS within 3 years post-ADS. Patients with MS did not differ from children with monophasic ADS in terms of cognitive performance at the 6-months follow-up. Fatigue symptoms were reported in 50% of patients, irrespective of MS diagnosis. Presence of brain lesions at onset and 6 months post-incident demyelinating event did not associate with cognitive outcome. Conclusions: Children with ADS experience a favorable short-term neurocognitive outcome, even those confirmed to have MS. Longitudinal evaluations of children with monophasic ADS and MS are required to determine the possibility of late-emerging sequelae and their time course. (JINS, 2016, 22, 1050–1060)
We present preliminary results of a galaxy redshift survey we are accomplishing as an ESO Key Project over about 40 square degrees in a region near the South Galactic Pole, to a limiting magnitude bJ = 19.4. Up to now ∼ 50% of the survey has been completed, providing about 2000 galaxy redshifts.
The ESO Slice Project (ESP) is a galaxy redshift survey we have recently completed as an ESO Key-Project over about 30 square degrees, in a region near the South Galactic Pole (Vettolani et al., submitted to A&A). The survey is nearly complete to the limiting magnitude bJ = 19.4 and consists of more than three thousands galaxies with reliable redshift determination.
The evidence underpinning the developmental origins of health and disease (DOHaD) is overwhelming. As the emphasis shifts more towards interventions and the translational strategies for disease prevention, it is important to capitalize on collaboration and knowledge sharing to maximize opportunities for discovery and replication. DOHaD meetings are facilitating this interaction. However, strategies to perpetuate focussed discussions and collaborations around and between conferences are more likely to facilitate the development of DOHaD research. For this reason, the DOHaD Society of Australia and New Zealand (DOHaD ANZ) has initiated themed Working Groups, which convened at the 2014–2015 conferences. This report introduces the DOHaD ANZ Working Groups and summarizes their plans and activities. One of the first Working Groups to form was the ActEarly birth cohort group, which is moving towards more translational goals. Reflecting growing emphasis on the impact of early life biodiversity – even before birth – we also have a Working Group titled Infection, inflammation and the microbiome. We have several Working Groups exploring other major non-cancerous disease outcomes over the lifespan, including Brain, behaviour and development and Obesity, cardiovascular and metabolic health. The Epigenetics and Animal Models Working Groups cut across all these areas and seeks to ensure interaction between researchers. Finally, we have a group focussed on ‘Translation, policy and communication’ which focusses on how we can best take the evidence we produce into the community to effect change. By coordinating and perpetuating DOHaD discussions in this way we aim to enhance DOHaD research in our region.
On May 22, 1989 the Japanese Ginga Team discovered a new X-ray source that was cataloged as GS 2023+338. This source was subsequently identified as coincident in position with a previously known nova cataloged as V404 Cygni. Its last recorded outburst was in 1938 when it rose to about 12th mag. Spectroscopic data were obtained and confirmed the nature of the outburst. Additional ground based data were obtained by us at CTIO and the VLA. The X-ray behavior of this object has been reported to be very unusual and it reached a peak of about 17 crab about one week after discovery. Since then it has varied widely in magnitude at all wavelengths at which it has been studied. We present a brief summary of the observations that have been obtained up to the time of the meeting and shortly thereafter.
Andromeda XXVII is a dwarf spheroidal galaxy in the outskirts of the Andromeda galaxy (M31). It appears to be dissolving in to the Northern arc of M31, and could be the remnant of a strong tidal disruption. In the upcoming months, our spectroscopic program, which has measured velocities for multiple stars within both the dwarf galaxy progenitor and its stream (using the Keck II DEIMOS telescope, as part of the PAndAS survey), will determine velocity dispersions, scale radii and metallicities of both the dwarf and the stream. This in turn may enable us to ascertain the progenitor mass profile and determine whether it is cusped or cored.
As part of the Z-PAndAS Keck II DEIMOS survey of resolved stars in our neighboring galaxy, Andromeda (M31), we have built up a unique data set of measured velocities and chemistries for thousands of stars in the Andromeda stellar halo, particularly probing its rich and complex substructure. In this contribution, we will discuss the structural, dynamical and chemical properties of Andromeda's dwarf spheroidal galaxies, and how there is no observational evidence for a difference in the evolutionary histories of those found on and off M31's vast plane of satellites. We will also discuss a possible extension to the most significant merger event in M31 - the Giant Southern Stream - and how we can use this feature to refine our understanding of M31's mass profile, and its complex evolution.
We have used dedicated 0.7m telescopes in California and Israel to image the halos of ~ 200 galaxies in the Local Volume to 29 mag/sq arcsec, the sample mainly drawn from the 2MASS Large Galaxy Atlas (LGA). We supplement the LGA sample with dwarf galaxies and more distant giant ellipticals. Low surface brightness halos exceeding 50 kpc in diameter are found only in galaxies more luminous than L*, and classic interaction signatures are relatively infrequent. Halo diameter is correlated with total galaxy luminosity. Extended low surface brightness halos are present even in galaxies as faint as MV = - 18. Edge-on galaxies with boxy bulges tend to lack extended spheroidal halos, while those with large classical bulges exhibit extended round halos, supporting the notions that boxy or barlike bulges originate from disks. Most face-on spiral galaxies present features that appear to be irregular extensions of spiral arms, although rare cases show smooth boundaries with no sign of star formation. Although we serendipitously discovered a dwarf galaxy undergoing tidal disruption in the halo of NGC 4449, we found no comparable examples in our general survey. A search for similar examples in the Local Volume identified hcc087, a tidally disrupting dwarf galaxy in the Hercules Cluster, but we do not confirm an anomalously large half-light radius reported for the dwarf VCC 1661.
The recording and analysis of a burnt mound and adjacent palaeochannel deposits on the floodplain of the River Soar in Leicestershire revealed that the burnt mound was in use, possibly for a number of different purposes, at the transition from the Neolithic to the Bronze Age. An extensive radiocarbon dating programme indicated that the site was revisited. Human remains from the palaeochannel comprised the remains of three individuals, two of whom pre-dated the burnt mound by several centuries while the partial remains of a third, dating from the Late Bronze Age, provided evidence that this individual had met a violent death. These finds, along with animal bones dating to the Iron Age, and the remains of a bridge from the early medieval period, suggest that people were drawn to this location over a long period of time.
The present work shows results on elemental distribution analyses in Cu(In,Ga)Se2 thin films for solar cells performed by use of wavelength-dispersive and energy-dispersive X-ray spectrometry (EDX) in a scanning electron microscope, EDX in a transmission electron microscope, X-ray photoelectron, angle-dependent soft X-ray emission, secondary ion-mass (SIMS), time-of-flight SIMS, sputtered neutral mass, glow-discharge optical emission and glow-discharge mass, Auger electron, and Rutherford backscattering spectrometry, by use of scanning Auger electron microscopy, Raman depth profiling, and Raman mapping, as well as by use of elastic recoil detection analysis, grazing-incidence X-ray and electron backscatter diffraction, and grazing-incidence X-ray fluorescence analysis. The Cu(In,Ga)Se2 thin films used for the present comparison were produced during the same identical deposition run and exhibit thicknesses of about 2 μm. The analysis techniques were compared with respect to their spatial and depth resolutions, measuring speeds, availabilities, and detection limits.
Real time optical studies have provided insights into the growth of hydrogenated amorphous silicon (a-Si:H) and microcrystalline silicon (μc-Si:H) thin films by plasma-enhanced chemical vapor deposition as a function of the H2-dilution gas flow ratio Research-article=[H2]/[SiH4], the accumulated film thickness db, and the substrate material. Results pertinent to the optimization of a-Si:H-based solar cells have been obtained in studies of Si film growth at moderate to high R on dense amorphous semiconductor film surfaces. For depositions with 15≤Research-article≤80 on freshly-deposited a-Si:H, initial film growth occurs in the amorphous phase. Upon continued growth, however, a transition is observed as crystallites begin to nucleate from the amorphous film. The thickness at which this amorphous-to-microcrystalline (a→μc) transition occurs is found to decrease with increasing R.Based on these results, a deposition phase diagram has been proposed that describes the a–gc transition as a continuous function of R and db. We find that the optimum stabilized a-Si:H p-i-n solar cell performance is obtained in an i-layer growth process that is maintained as close as possible to the phase boundary (but on the amorphous side) versus film thickness.
A prototype expanded-beam spectroscopic ellipsometer has been developed that uses uncollimated (non-parallel, diffuse) illumination with a detection system consisting of an angle-of-incidence-sensitive pinhole camera for high-speed, large-area imaging/mapping applications. The performance of this novel instrument is being tested for imaging/mapping of mixed-phase hydrogenated silicon films having graded amorphous (a-Si:H) and nanocrystalline (nc-Si:H) components throughout the film depth. The speed of the measurement system makes the instrument suitable for use on production lines. The precision enables detection of subnanometer thicknesses, and refractive index and extinction coefficient changes of 0.01. Angle-of-incidence and mirror calibrations are made via well-known sample structures. Alternative commercial instrumentation for mapping by spectroscopic ellipsometry must translate the sample or ellipsometer in two dimensions. For this instrumentation, even a 15 × 15 cm2 sample with cm2 resolution requires > 200 measurements and at least 15 min. By imaging along one dimension in parallel, the expanded-beam system can measure with similar resolution in < 2 min. The focus of recent instrumentation efforts is on improving the overall system spectral range and its performance.