99 research outputs found

    An investigation into the tourism and hospitality scholarly activity currently being undertaken in Irish higher education institutions

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    The purpose of this article is to describe the tourism and hospitality scholarly activity currently taking place in Irish higher education (HE) institutions. A number of approaches to tourism and hospitality research are identified in the literature. In order to understand the policy and practice within the Irish HE sector, qualitative research was conducted through a survey of tourism and hospitality academics and researchers within Irish HE institutions. The findings suggest that tourism and hospitality scholarly activity in Ireland is being carried out in many ways, including through joint research projects between Irish HE institutions and industry. This is a positive step towards achieving research and industry harmony. The development of stand-alone research centres within these institutions can also promote and attract funding for tourism and hospitality research activities

    Determinants of seasonal changes in availability of food patches for elephants (Loxodonta africana) in a semi-arid African savanna

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    Loss of biodiversity caused by impact of elephants (Loxodonta africana) on African woodlands may require a management response, but any action should be based on an understanding of why elephants choose to utilise trees destructively. Comprehension of elephant feeding behaviour requires consideration of the relative value of the plant groups they may potentially consume. Profitability of available food is partly determined by the time to locate a food patch and, therefore, as a foundation for understanding the influence of food availability on diet selection, key controls on the density of grass, forb, and browse patches were investigated across space and time in a semi-arid African savanna. Density of food patches changed seasonally because plant life-forms required different volumes of soil water to produce green forage; and woody plants and forbs responded to long-term changes in soil moisture, while grasses responded to short-term moisture pulses. Soil texture, structure of woody vegetation and fire added further complexity by altering the soil water thresholds required for production of green forage. Interpolating between regularly-timed, ground-based measurements of food density by using modelled soil water as the predictor in regression equations may be a feasible method of quantifying food available to elephants in complex savanna environments.EM201

    Systematic land-cover change in KwaZulu-Natal, South Africa: Implications for biodiversity.

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    Land-cover change and habitat loss are widely recognised as the major drivers of biodiversity loss in the world. Land-cover maps derived from satellite imagery provide useful tools for monitoring land-use and land-cover change. KwaZulu-Natal, a populous yet biodiversity-rich province in South Africa, is one of the first provinces to produce a set of three directly comparable land-cover maps (2005, 2008 and 2011). These maps were used to investigate systematic land-cover changes occurring in the province with a focus on biodiversity conservation. The Intensity Analysis framework was used for the analysis as this quantitative hierarchical method addresses shortcomings of other established land-cover change analyses. In only 6 years (2005-2011), a massive 7.6% of the natural habitat of the province was lost to anthropogenic transformation of the landscape. The major drivers of habitat loss were agriculture, timber plantations, the built environment, dams and mines. Categorical swapping formed a significant part of landscape change, including a return from anthropogenic categories to secondary vegetation, which we suggest should be tracked in analyses. Longer-term rates of habitat loss were determined using additional land-cover maps (1994, 2000). An average of 1.2% of the natural landscape has been transformed per annum since 1994. Apart from the direct loss of natural habitat, the anthropogenically transformed land covers all pose additional negative impacts for biodiversity remaining in these or surrounding areas. A target of no more than 50% of habitat loss should be adopted to adequately conserve biodiversity in the province. Our analysis provides the first provincial assessment of the rate of loss of natural habitat and may be used to fulfil incomplete criteria used in the identification of Threatened Terrestrial Ecosystems, and to report on the Convention on Biological Diversity targets on rates of natural habitat loss.SP201

    Topo-edaphic environment and forestry plantation disturbance affect the distribution of grassland forage and non-forage resources, Maputaland, South Africa

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    Grasslands are integral to rural livelihoods in southern Africa, because they provide hydrological regulation services and a variety of plant resources, including livestock fodder, medicines, and food products. To ensure ongoing provision of these resources in rapidly developing rural landscapes, an understanding of the relationships between grassland species composition and ecosystem services is required. This study examines the provision of grassland forage and non-forage resources across five grassland types in relation to environmental determinants of site topography, soil conditions, and plantation-forestry disturbance. Grasslands characteristic of low-lying and fertile landscape positions were dominated by nutritious lawn grasses and therefore tended to complement rangeland practices, whereas grasslands associated with elevated areas or infertile conditions were diverse in species composition and consequently provided the majority of plant medicines, spiritual resources, fruit-beverage resources, oils, and craft materials. Secondary grassland, resulting from forestry plantation abandonment, had moderate forage potential and limited non-forage resources. Our results provide a simple framework for approaching grassland resource classification, grassland conservation and land use management on the Maputaland coastal plain.The Water Research Commission (WRC) of South Africa and the Department of Economic Development, Tourism and Environmental Affairs (EDTEA).http://www.tandfonline.com/loi/tarf202021-12-08hj2021Plant Production and Soil Scienc

    The HERMES Dual-Radiator Ring Imaging Cerenkov Detector

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    The construction and use of a dual radiator Ring Imaging Cerenkov(RICH) detector is described. This instrument was developed for the HERMES experiment at DESY which emphasizes measurements of semi-inclusive deep-inelastic scattering. It provides particle identification for pions, kaons, and protons in the momentum range from 2 to 15 GeV, which is essential to these studies. The instrument uses two radiators, C4F10, a heavy fluorocarbon gas, and a wall of silica aerogel tiles. The use of aerogel in a RICH detector has only recently become possible with the development of clear, large homogeneous and hydrophobic aerogel. A lightweight mirror was constructed using a newly perfected technique to make resin-coated carbon-fiber surfaces of optical quality. The photon detector consists of 1934 photomultiplier tubes for each detector half, held in a soft steel matrix to provide shielding against the residual field of the main spectrometer magnet.Comment: 25 pages, 23 figure

    Prenatal metal(loid) mixtures and birth weight for gestational age: A pooled analysis of three cohorts participating in the ECHO program

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    Background: A growing number of studies have identified both toxic and essential metals which influence fetal growth. However, most studies have conducted single-cohort analyses, which are often limited by narrow exposure ranges, and evaluated metals individually. The objective of the current study was to conduct an environmental mixture analysis of metal impacts on fetal growth, pooling data from three geographically and demographically diverse cohorts in the United States participating in the Environmental Influences on Child Health Outcomes program. Methods: The pooled sample (N = 1,002) included participants from the MADRES, NHBCS, and PROTECT cohorts. Associations between seven metals (antimony, cadmium, cobalt, mercury, molybdenum, nickel, tin) measured in maternal urine samples collected during pregnancy (median: 16.0 weeks gestation) and birth weight for gestational age z-scores (BW for GA) were investigated using Bayesian Kernel Machine Regression (BKMR). Models were also stratified by cohort and infant sex to investigate possible heterogeneity. Chromium and uranium concentrations fell below the limits of detection for most participants and were evaluated separately as binary variables using pooled linear regression models. Results: In the pooled BKMR analysis, antimony, mercury, and tin were inversely and linearly associated with BW for GA, while a positive linear association was identified for nickel. The inverse association between antimony and BW for GA was observed in both males and females and for all three cohorts but was strongest for MADRES, a predominantly low-income Hispanic cohort in Los Angeles. A reverse j-shaped association was identified between cobalt and BW for GA, which was driven by female infants. Pooled associations were null for cadmium, chromium, molybdenum, and uranium, and BKMR did not identify potential interactions between metal pairs. Conclusions: Findings suggest that antimony, an understudied metalloid, may adversely impact fetal growth. Cohort- and/or sex-dependent associations were identified for many of the metals, which merit additional investigation

    Birth Outcomes in Relation to Prenatal Exposure to Per- and Polyfluoroalkyl Substances and Stress in the Environmental Influences on Child Health Outcomes (ECHO) Program

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    BACKGROUND: Per- and polyfluoroalkyl substances (PFAS) are persistent and ubiquitous chemicals associated with risk of adverse birth outcomes. Results of previous studies have been inconsistent. Associations between PFAS and birth outcomes may be affected by psychosocial stress. OBJECTIVES: We estimated risk of adverse birth outcomes in relation to prenatal PFAS concentrations and evaluate whether maternal stress modifies those relationships. METHODS: We included 3,339 participants from 11 prospective prenatal cohorts in the Environmental influences on the Child Health Outcomes (ECHO) program to estimate the associations of five PFAS and birth outcomes. We stratified by perceived stress scale scores to examine effect modification and used Bayesian Weighted Sums to estimate mixtures of PFAS. RESULTS: We observed reduced birth size with increased concentrations of all PFAS. For a 1-unit higher log-normalized exposure to perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), perfluorononanoic acid (PFNA), and perfluorohexane sulfonic acid (PFHxS), we observed lower birthweight-for-gestational-age z-scores of formula presented [95% confidence interval (CI): formula presented ], formula presented (95% CI: formula presented ), formula presented (95% CI: formula presented ), formula presented (95% CI: formula presented , 0.06), and formula presented (95% CI: formula presented ), respectively. We observed a lower odds ratio (OR) for large-for-gestational-age: formula presented (95% CI: 0.38, 0.83), formula presented (95% CI: 0.35, 0.77). For a 1-unit increase in log-normalized concentration of summed PFAS, we observed a lower birthweight-for-gestational-age z-score [formula presented ; 95% highest posterior density (HPD): formula presented ] and decreased odds of large-for-gestational-age (formula presented ; 95% HPD: 0.29, 0.82). Perfluorodecanoic acid (PFDA) explained the highest percentage (40%) of the summed effect in both models. Associations were not modified by maternal perceived stress. DISCUSSION: Our large, multi-cohort study of PFAS and adverse birth outcomes found a negative association between prenatal PFAS and birthweight-for-gestational-age, and the associations were not different in groups with high vs. low perceived stress. This study can help inform policy to reduce exposures in the environment and humans. https://doi.org/10.1289/EHP10723

    Integrated motor drives: state of the art and future trends

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    With increased need for high power density, high efficiency and high temperature capabilities in Aerospace and Automotive applications, Integrated Motor Drives (IMD) offers a potential solution. However, close physical integration of the converter and the machine may also lead to an increase in components temperature. This requires careful mechanical, structural and thermal analysis; and design of the IMD system. This paper reviews existing IMD technologies and their thermal effects on the IMD system. The effects of the power electronics (PE) position on the IMD system and its respective thermal management concepts are also investigated. The challenges faced in designing and manufacturing of an IMD along with the mechanical and structural impacts of close physical integration is also discussed and potential solutions are provided. Potential converter topologies for an IMD like the Matrix converter, 2-level Bridge, 3-level NPC and Multiphase full bridge converters are also reviewed. Wide band gap devices like SiC and GaN and their packaging in power modules for IMDs are also discussed. Power modules components and packaging technologies are also presented

    Health Care Utilization During the COVID-19 Pandemic Among Individuals Born Preterm

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    Importance: Limited data exist on pediatric health care utilization during the COVID-19 pandemic among children and young adults born preterm. Objective: To investigate differences in health care use related to COVID-19 concerns during the pandemic among children and young adults born preterm vs those born at term. Design, Setting, and Participants: In this cohort study, questionnaires regarding COVID-19 and health care utilization were completed by 1691 mother-offspring pairs from 42 pediatric cohorts in the National Institutes of Health Environmental Influences on Child Health Outcomes Program. Children and young adults (ages 1-18 years) in these analyses were born between 2003 and 2021. Data were recorded by the August 31, 2021, data-lock date and were analyzed between October 2021 and October 2022. Exposures: Premature birth (<37 weeks' gestation). Main Outcomes and Measures: The main outcome was health care utilization related to COVID-19 concerns (hospitalization, in-person clinic or emergency department visit, phone or telehealth evaluations). Individuals born preterm vs term (≥37 weeks' gestation) and differences among preterm subgroups of individuals (<28 weeks', 28-36 weeks' vs ≥37 weeks' gestation) were assessed. Generalized estimating equations assessed population odds for health care used and related symptoms, controlling for maternal age, education, and psychiatric disorder; offspring history of bronchopulmonary dysplasia (BPD) or asthma; and timing and age at COVID-19 questionnaire completion. Results: Data from 1691 children and young adults were analyzed; among 270 individuals born preterm, the mean (SD) age at survey completion was 8.8 (4.4) years, 151 (55.9%) were male, and 193 (71.5%) had a history of BPD or asthma diagnosis. Among 1421 comparison individuals with term birth, the mean (SD) age at survey completion was 8.4 (2.4) years, 749 (52.7%) were male, and 233 (16.4%) had a history of BPD or asthma. Preterm subgroups included 159 individuals (58.5%) born at less than 28 weeks' gestation. In adjusted analyses, individuals born preterm had a significantly higher odds of health care utilization related to COVID-19 concerns (adjusted odds ratio [aOR], 1.70; 95% CI, 1.21-2.38) compared with term-born individuals; similar differences were also seen for the subgroup of individuals born at less than 28 weeks' gestation (aOR, 2.15; 95% CI, 1.40-3.29). Maternal history of a psychiatric disorder was a significant covariate associated with health care utilization for all individuals (aOR, 1.44; 95% CI, 1.17-1.78). Conclusions and Relevance: These findings suggest that during the COVID-19 pandemic, children and young adults born preterm were more likely to have used health care related to COVID-19 concerns compared with their term-born peers, independent of a history of BPD or asthma. Further exploration of factors associated with COVID-19-related health care use may facilitate refinement of care models
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