774 research outputs found

    Effect of air pollution controls on black smoke and sulfur dioxide concentrations across Ireland

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    During the 1980s Ireland experienced severe pollution episodes, principally because of domestic coal burning. In 1990, the Irish government introduced a ban on the marketing, sale, and distribution of coal in Dublin. They extended the ban to Cork in 1995 and to ten other communities in 1998 and 2000. We previously reported declines in particulate (black smoke [BS]) and sulfur dioxide (SO2) concentrations in Dublin following the 1990 coal ban. We now explore and compare the effectiveness of these sequential bans in 1990, 1995, 1998, and 2000. Daily BS and total gaseous acidity (502) measurements were compiled between 1980 and 2004. We calculated descriptive statistics for the pre-ban (5 yr before ban) and post-ban (5 yr after ban) periods for BS and SO2 concentrations and for season-specific periods. Mean BS levels fell in all centers post-ban compared with the pre-ban period, with decreases ranging; from 4 to 35 mu g.m(-3) (-45 to -70%). These reductions were smallest in the summer and largest in the winter. These BS, reductions were sustained in all centers until the end of the study period. We observed no clear pattern in SO2 changes associated with the coal bans. The 1990, 1995, 1998, and 2000 Irish coal sale bans resulted in immediate and sustained decreases in particulate levels in centers, with the largest declines in the winter. In contrast, we did not observe consistent declines in total acidity as a measure of SO2. It may be that coal was not the major source. of SO2. Simple legislation was very effective at improving ambient air quality in Irish cities with varying populations, geography/topography, and meteorological conditions

    Fuel poverty, older people and cold weather: An all-island analysis

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    Executive Summary This report covers a number of different aspects of fuel poverty and older people. 1. An exploration of existing government survey data from Northern Ireland and the Republic of Ireland with a particular focus on older people and conducting additional targeted analyses where required. 2. An original survey in the Republic of Ireland exploring the lived experience of older people in cold weather. 3. A feasibility study of data logging thermometers placed in the homes of older tenants in local authority accommodation. 4. Analysis of excess winter mortality among older people including a consideration of differences between the two jurisdictions. Older people on the island of Ireland, as in many other countries, experience a ‘dual burden’ in terms of fuel poverty. They are more likely to experience fuel poverty and are also particularly vulnerable to health and social harm as a result of this experience. The numbers of older people vulnerable to ill-effects from cold homes will rise as numbers of people aged 80 and over, and those living with chronic illness or disability, increase. There were significant differences observed between expenditure-based, and subjective (EU-SILC) based fuel poverty indicators, for older people, and between Northern Ireland and Republic of Ireland data. This data required careful interpretation. The higher levels of fuel poverty recorded for older people on the island of Ireland appeared to be driven by all aspects of the fuel poverty model - poor housing condition, energy inefficient housing, rising fuel prices and low income. The majority of older people live in their own home and these homes tend to be older properties which are detached or semi-detached. Older people on the island are over-represented among houses which are in poor condition and which lack central heating in both jurisdictions. Lacking central heating was a more common experience for older people in the Republic of Ireland than in Northern Ireland. Data on energy efficiency measures were not comparable North/South but similar patterns were observed. Older people were less likely than the general population to have attic/loft or wall insulation or double glazing. Older people were also vulnerable from an income point of view. This would seem to be a particular issue in Northern Ireland where rates of income poverty are significantly increasing. In both jurisdictions older people were heavily reliant on social transfers to keep them out of poverty. Coupled with this, there is evidence that many older people are not claiming their full entitlements. Oil dependency was a particular issue in Northern Ireland. Very significant increases were observed in the price of heating oil, as well as electricity and gas in recent years. There was little available research evidence on the relationship between the older consumer and heating oil suppliers

    {\phi}^4 Solitary Waves in a Parabolic Potential: Existence, Stability, and Collisional Dynamics

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    We explore a {\phi}^4 model with an added external parabolic potential term. This term dramatically alters the spectral properties of the system. We identify single and multiple kink solutions and examine their stability features; importantly, all of the stationary structures turn out to be unstable. We complement these with a dynamical study of the evolution of a single kink in the trap, as well as of the scattering of kink and anti-kink solutions of the model. We see that some of the key characteristics of kink-antikink collisions, such as the critical velocity and the multi-bounce windows, are sensitively dependent on the trap strength parameter, as well as the initial displacement of the kink and antikink

    The association of cold weather and all-cause and cause-specific mortality in the island of Ireland between 1984 and 2007

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    This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.This article has been made available through the Brunel Open Access Publishing Fund.Background This study aimed to assess the relationship between cold temperature and daily mortality in the Republic of Ireland (ROI) and Northern Ireland (NI), and to explore any differences in the population responses between the two jurisdictions. Methods A time-stratified case-crossover approach was used to examine this relationship in two adult national populations, between 1984 and 2007. Daily mortality risk was examined in association with exposure to daily maximum temperatures on the same day and up to 6 weeks preceding death, during the winter (December-February) and cold period (October-March), using distributed lag models. Model stratification by age and gender assessed for modification of the cold weather-mortality relationship. Results In the ROI, the impact of cold weather in winter persisted up to 35 days, with a cumulative mortality increase for all-causes of 6.4% (95%CI=4.8%-7.9%) in relation to every 1oC drop in daily maximum temperature, similar increases for cardiovascular disease (CVD) and stroke, and twice as much for respiratory causes. In NI, these associations were less pronounced for CVD causes, and overall extended up to 28 days. Effects of cold weather on mortality increased with age in both jurisdictions, and some suggestive gender differences were observed. Conclusions The study findings indicated strong cold weather-mortality associations in the island of Ireland; these effects were less persistent, and for CVD mortality, smaller in NI than in the ROI. Together with suggestive differences in associations by age and gender between the two Irish jurisdictions, the findings suggest potential contribution of underlying societal differences, and require further exploration. The evidence provided here will hope to contribute to the current efforts to modify fuel policy and reduce winter mortality in Ireland

    On The Power of Tree Projections: Structural Tractability of Enumerating CSP Solutions

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    The problem of deciding whether CSP instances admit solutions has been deeply studied in the literature, and several structural tractability results have been derived so far. However, constraint satisfaction comes in practice as a computation problem where the focus is either on finding one solution, or on enumerating all solutions, possibly projected to some given set of output variables. The paper investigates the structural tractability of the problem of enumerating (possibly projected) solutions, where tractability means here computable with polynomial delay (WPD), since in general exponentially many solutions may be computed. A general framework based on the notion of tree projection of hypergraphs is considered, which generalizes all known decomposition methods. Tractability results have been obtained both for classes of structures where output variables are part of their specification, and for classes of structures where computability WPD must be ensured for any possible set of output variables. These results are shown to be tight, by exhibiting dichotomies for classes of structures having bounded arity and where the tree decomposition method is considered

    Contaminations contaminate common databases

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    The polymerase chain reaction (PCR) is a very powerful method to detect and identify pathogens. The high sensitivity of the method, however, comes with a cost; any of the millions of artificial DNA copies generated by PCR can serve as a template in a following experiment. If not identified as contaminations, these may result in erroneous conclusions on the occurrence of the pathogen, thereby inflating estimates of host range and geographic distribution. In the present paper, we evaluate whether several published records of avian haemosporidian parasites, in either unusual host species or geographical regions, might stem from PCR contaminations rather than novel biological findings. The detailed descriptions of these cases are shedding light upon the steps in the work process that might lead to PCR contaminations. By increasing the awareness of this problem, it will aid in developing procedures that keep these to a minimum. The examples in the present paper are from haemosporidians of birds, however the problem of contaminations and suggested actions should apply generally to all kinds of PCR‐based identifications, not just of parasites and pathogens

    Voltage-programmable liquid optical interface

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    Recently, there has been intense interest in photonic devices based on microfluidics, including displays and refractive tunable microlenses and optical beamsteerers, that work using the principle of electrowetting. Here, we report a novel approach to optical devices in which static wrinkles are produced at the surface of a thin film of oil as a result of dielectrophoretic forces. We have demonstrated this voltage-programmable surface wrinkling effect in periodic devices with pitch lengths of between 20 and 240 µm and with response times of less than 40 µs. By a careful choice of oils, it is possible to optimize either for high-amplitude sinusoidal wrinkles at micrometre-scale pitches or more complex non-sinusoidal profiles with higher Fourier components at longer pitches. This opens up the possibility of developing rapidly responsive voltage-programmable, polarization-insensitive transmission and reflection diffraction devices and arbitrary surface profile optical devices

    Primary peritoneal and ovarian cancers: an epidemiological comparative analysis

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    We performed case–control analyses using data from the North Carolina Ovarian Cancer Study to determine risk factors that distinguish primary peritoneal cancer (PPC) from epithelial ovarian cancer (EOC). Our risk factor analyses were restricted to invasive serous cancers including 495 EOC cases, 62 PPC cases and 1,086 control women. Logistic regression analyses were used to calculate adjusted odds ratios and 95% confidence intervals for risk factor associations. Although many case–control associations for the invasive serous PPC cases were similar to those of the invasive serous EOC cases, some differences were observed including a twofold increase in risk of invasive serous PPC in women who were ≥35 years at last pregnancy, whereas a decreased risk was observed for invasive serous EOC risk. We could not confirm a previous report of an association between tubal ligation and PPC, a factor consistently associated with a decreased risk of EOC. The difference in the risk factor associations between invasive serous PPC and EOC cancers suggests divergent molecular development of peritoneal and ovarian cancers. A larger study to determine risk factors for invasive serous PPC is warranted

    Transiently achieved very low low-density lipoprotein cholesterol levels by statin and alirocumab after acute coronary syndrome are associated with cardiovascular risk reduction: the ODYSSEY OUTCOMES trial

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    Aims Long-term, placebo-controlled cholesterol-lowering trials have demonstrated legacy effects (clinical benefits that persist or emerge after trial end). It is unknown whether legacy effects follow a short period of very low low-density lipoprotein cholesterol (LDL-C) levels achieved with statin plus proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor. Methods and results In 18 924 patients with recent acute coronary syndrome, the ODYSSEY OUTCOMES trial compared the PCSK9 inhibitor alirocumab with placebo, each added to high-intensity or maximum-tolerated statin therapy. Patients with two consecutive LDL-C levels <0.39 mmol/L (15 mg/dL) on alirocumab had blinded placebo substitution for the remainder of the trial with continued statin treatment. In post hoc analyses, major adverse cardiovascular events (MACE) in these patients were compared to MACE in propensity score–matched patients from the placebo group with similar baseline characteristics and study medication adherence. In the alirocumab group, 730 patients had blinded placebo substitution at a median of 8.3 months from randomization, after a median of 6.0 months with LDL-C <0.39 mmol/L. They were matched to 1460 placebo patients. Both groups had lower baseline LDL-C and lipoprotein(a) and better study medication adherence than those of the overall cohort. Over a median follow-up of 2.8 years, MACE occurred in 47 (6.4%) alirocumab patients with limited-duration, very low achieved LDL-C vs. 122 (8.4%) matched placebo patients (treatment hazard ratio 0.72; 95% confidence interval 0.51, 0.997; P = 0.047). Conclusion A short period of LDL-C levels <0.39 mmol/L achieved with statin and alirocumab, followed by statin monotherapy, was associated with a lower risk of MACE than statin monotherapy throughout the observation period. Clinical benefit persisted for several years

    A new concept for the combination of optical interferometers and high-resolution spectrographs

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    The combination of high spatial and spectral resolution in optical astronomy enables new observational approaches to many open problems in stellar and circumstellar astrophysics. However, constructing a high-resolution spectrograph for an interferometer is a costly and time-intensive undertaking. Our aim is to show that, by coupling existing high-resolution spectrographs to existing interferometers, one could observe in the domain of high spectral and spatial resolution, and avoid the construction of a new complex and expensive instrument. We investigate in this article the different challenges which arise from combining an interferometer with a high-resolution spectrograph. The requirements for the different sub-systems are determined, with special attention given to the problems of fringe tracking and dispersion. A concept study for the combination of the VLTI (Very Large Telescope Interferometer) with UVES (UV-Visual Echelle Spectrograph) is carried out, and several other specific instrument pairings are discussed. We show that the proposed combination of an interferometer with a high-resolution spectrograph is indeed feasible with current technology, for a fraction of the cost of building a whole new spectrograph. The impact on the existing instruments and their ongoing programs would be minimal.Comment: 27 pages, 9 figures, Experimental Astronomy; v2: accepted versio
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