171 resultados para gastrointestinal transit


Relevância:

10.00% 10.00%

Publicador:

Resumo:

Insulated rail joints (IRJs) possess lower bending stiffness across the gap containing insulating endpost and hence are subjected to wheel impact. IRJs are either square cut or inclined cut to the longitudinal axis of the rails in a vertical plane. It is generally claimed that the inclined cut IRJs outperformed the square cut IRJs; however, there is a paucity of literature with regard to the relative structural merits of these two designs. This article presents comparative studies of the structural response of these two IRJs to the passage of wheels based on continuously acquired field data from joints strain-gauged closer to the source of impact. Strain signatures are presented in time, frequency, and avelet domains and the peak vertical and shear strains are systematically employed to examine the relative structural merits of the two IRJs subjected to similar real-life loading. It is shown that the inclined IRJs resist the wheel load with higher peak shear strains and lower peak vertical strains than that of the square IRJs.

Relevância:

10.00% 10.00%

Publicador:

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Despite the evidence that Australia’s children are learning literacy, there is also significant evidence that the poorest and most disadvantaged children are being left behind. To date our understanding of the place of transitions in this has been limited, although there has been work on the fourth grade slump (Gee, 2000, 2008), the transition from primary years to secondary years (e.g. Bahr & Pendergast, 2007; Pendergast & Bahr, 2005, 2010), and transitions when changing schools (Henderson, 2008). In this chapter, we consider the notion of transitioning, as we unpack issues related to recognising and valuing student diversity and difference. We want to highlight ways of providing high quality and high equity literacy pedagogy and literacy outcomes for middle years students. We will also discuss the importance of recognising that students transit to schools and school learning from other significant contexts, each with their own combinations of literacy practices, rituals and values.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The Giant Long-Armed Prawn, Macrobrachium lar is a freshwater species native to the Indo-Pacific. M. lar has a long-lived, passive, pelagic marine larval stage where larvae need to colonise freshwater within three months to complete their development. Dispersal is likely to be influenced by the extensive distances larvae must transit between small oceanic islands to find suitable freshwater habitat, and by prevailing east to west wind and ocean currents in the southern Pacific Ocean. Thus, both intrinsic and extrinsic factors are likely to influence wild population structure in this species. The present study sought to define the contemporary broad and fine-scale population genetic structure of Macrobrachium lar in the south-western Pacific Ocean. Three polymorphic microsatellite loci were used to assess patterns of genetic variation within and among 19 wild adult sample sites. Statistical procedures that partition variation implied that at both spatial scales, essentially all variation was present within sample sites and differentiation among sites was low. Any differentiation observed also was not correlated with geographical distance. Statistical approaches that measure genetic distance, at the broad-scale, showed that all south-western Pacific Islands were essentially homogeneous, with the exception of a well supported divergent Cook Islands group. These findings are likely the result of some combination of factors that may include the potential for allelic homoplasy, through to the effects of sampling regime. Based on the findings, there is most likely a divergent M. lar Cook Islands clade in the south-western Pacific Ocean, resulting from prevailing ocean currents. Confirmation of this pattern will require a more detailed analysis of nDNA variation using a larger number of loci and, where possible, use of larger population sizes.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Sustainability concerns every citizen. Housing affordability and sustainable solutions are being highlighted in research and practice in many parts of the world. This paper discusses the development of a Commuter Energy and Building Utilities System (CEBUS) in sustainable housing projects as a means of bridging the gap between current median house pricing and target affordable house pricing for low income earners. Similar scales of sustainable housing development cannot be achieved through independent application of current best practice methods in ecologically sustainable development strategies or transit oriented development master plans. This paper presents the initial stage of research on first capital and ongoing utilities and transport cost savings available from these sustainable design methods. It also outlines further research and development of a CEBUS Dynamic Simulation Model and Conceptual Framework for the Australian property development and construction industry.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The presence of High Speed Rail (HSR) systems influences market shares of road and air transport, and the development of cities and regions they serve. With the deployment of HSR infrastructure, changes in accessibility have occurred. These changes have lead researchers to investigate effects on the economic and spatial derived variables. Contention exists when managing the trade off between efficiency, and access points which are usually in the range of hundreds of kilometres apart. In short, it is argued that intermediate cities, bypassed by HSR services, suffer a decline in their accessibility and developmental opportunities. The present Chapter will analyse possible impacts derived from the presence of HSR infrastructure. In particular, it will consider small and medium agglomerations in the vicinity of HSR corridors, not always served by HSR stations. Thus, a methodology is developed to quantify accessibility benefits and their distribution. These benefits will be investigated in relation to different rail transit strategies integrating HSR infrastructure where a HSR station cannot be positioned. These strategies are selected principally for the type of service offered: (i) cadenced, (ii) express, (iii) frequent or (iv) non-stopping. Furthermore, to ground the theoretical approach linking accessibility and competitiveness, a case study in the North-Eastern Italian regions will be used for the application of the accessibility distributive patterns between the HSR infrastructure and the selected strategies. Results indicate that benefits derive from well informed decisions on HSR station positioning and the appropriate blend of complementary services in the whole region to interface HSR infrastructure. The results are significant for all countries in Europe and worldwide, not only for investing in HSR infrastructure, but mostly in terms of building territorial cohesion, while seeking international recognition for developing successful new technology and systems.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Notwithstanding the obvious potential advantages of information and communications technology (ICT) in the enhanced provision of healthcare services, there are some concerns associated with integration of and access to electronic health records. A security violation in health records, such as an unauthorised disclosure or unauthorised alteration of an individual's health information, can significantly undermine both healthcare providers' and consumers' confidence and trust in e-health systems. A crisis in confidence in any national level e-health system could seriously degrade the realisation of the system's potential benefits. In response to the privacy and security requirements for the protection of health information, this research project investigated national and international e-health development activities to identify the necessary requirements for the creation of a trusted health information system architecture consistent with legislative and regulatory requirements and relevant health informatics standards. The research examined the appropriateness and sustainability of the current approaches for the protection of health information. It then proposed an architecture to facilitate the viable and sustainable enforcement of privacy and security in health information systems under the project title "Open and Trusted Health Information Systems (OTHIS)". OTHIS addresses necessary security controls to protect sensitive health information when such data is at rest, during processing and in transit with three separate and achievable security function-based concepts and modules: a) Health Informatics Application Security (HIAS); b) Health Informatics Access Control (HIAC); and c) Health Informatics Network Security (HINS). The outcome of this research is a roadmap for a viable and sustainable architecture for providing robust protection and security of health information including elucidations of three achievable security control subsystem requirements within the proposed architecture. The successful completion of two proof-of-concept prototypes demonstrated the comprehensibility, feasibility and practicality of the HIAC and HIAS models for the development and assessment of trusted health systems. Meanwhile, the OTHIS architecture has provided guidance for technical and security design appropriate to the development and implementation of trusted health information systems whilst simultaneously offering guidance for ongoing research projects. The socio-economic implications of this research can be summarised in the fact that this research embraces the need for low cost security strategies against economic realities by using open-source technologies for overall test implementation. This allows the proposed architecture to be publicly accessible, providing a platform for interoperability to meet real-world application security demands. On the whole, the OTHIS architecture sets a high level of security standard for the establishment and maintenance of both current and future health information systems. This thereby increases healthcare providers‘ and consumers‘ trust in the adoption of electronic health records to realise the associated benefits.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

BACKGROUND: Enterococcus faecalis and Enterococcus faecium are associated with faecal pollution of water, linked to swimmer-associated gastroenteritis and demonstrate a wide range of antibiotic resistance. The Coomera River is a main water source for the Pimpama-Coomera watershed and is located in South East Queensland, Australia, which is used intensively for agriculture and recreational purposes. This study investigated the diversity of E. faecalis and E. faecium using Single Nucleotide Polymorphisms (SNPs) and associated antibiotic resistance profiles. RESULTS: Total enterococcal counts (cfu/ml) for three/six sampling sites were above the United States Environmental Protection Agency (USEPA) recommended level during rainfall periods and fall into categories B and C of the Australian National Health and Medical Research Council (NHMRC) guidelines (with a 1-10% gastrointestinal illness risk). E. faecalis and E. faecium isolates were grouped into 29 and 23 SNP profiles (validated by MLST analysis) respectively. This study showed the high diversity of E. faecalis and E. faecium over a period of two years and both human-related and human-specific SNP profiles were identified. 81.8% of E. faecalis and 70.21% of E. faecium SNP profiles were associated with genotypic and phenotypic antibiotic resistance. Gentamicin resistance was higher in E. faecalis (47% resistant) and harboured the aac(6')-aph(2') gene. Ciprofloxacin resistance was more common in E. faecium (12.7% resistant) and gyrA gene mutations were detected in these isolates. Tetracycline resistance was less common in both species while tet(L) and tet(M) genes were more prevalent. Ampicillin resistance was only found in E. faecium isolates with mutations in the pbp5 gene. Vancomycin resistance was not detected in any of the isolates. We found that antibiotic resistance profiles further sub-divided the SNP profiles of both E. faecalis and E. faecium. CONCLUSIONS: The distribution of E. faecalis and E. faecium genotypes is highly diverse in the Coomera River. The SNP genotyping method is rapid and robust and can be applied to study the diversity of E. faecalis and E. faecium in waterways. It can also be used to test for human-related and human-specific enterococci in water. The resolving power can be increased by including antibiotic-resistant profiles which can be used as a possible source tracking tool. This warrants further investigation.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This paper is the third in a series of reviews of cross-cultural studies of symptoms at midlife. The goal of this review is to examine methods used previously in cross-cultural studies of menopause and women's health at midlife to (1) identify challenges in the measurement of somatic symptoms across cultures and (2) recommend questions and tools that can be used in future research. This review also aims to examine the determinants of somatic symptoms. The review concludes that methods used for assessing somatic symptoms differ across studies. Somatic symptoms, particularly, aches, pain, and fatigue have a high prevalence. Statistically significant differences were seen in the prevalence of somatic symptoms across cultures. Based on the number of studies that demonstrated cross-cultural differences in symptom prevalence, we recommend that the following symptoms be included in future studies of symptoms at midlife: headaches, aches/pain, palpitations, dizziness, fatigue, breathing difficulties, numbness or tingling, and gastrointestinal difficulties. We also recommend that objective measures of physical function be administered when possible to supplement subjective self-evaluation.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Ultrafine particles (UFPs, <100 nm) are produced in large quantities by vehicular combustion and are implicated in causing several adverse human health effects. Recent work has suggested that a large proportion of daily UFP exposure may occur during commuting. However, the determinants, variability and transport mode-dependence of such exposure are not well-understood. The aim of this review was to address these knowledge gaps by distilling the results of ‘in-transit’ UFP exposure studies performed to-date, including studies of health effects. We identified 47 exposure studies performed across 6 transport modes: automobile, bicycle, bus, ferry, rail and walking. These encompassed approximately 3000 individual trips where UFP concentrations were measured. After weighting mean UFP concentrations by the number of trips in which they were collected, we found overall mean UFP concentrations of 3.4, 4.2, 4.5, 4.7, 4.9 and 5.7 × 10^4 particles cm^-3 for the bicycle, bus, automobile, rail, walking and ferry modes, respectively. The mean concentration inside automobiles travelling through tunnels was 3.0 × 10^5 particles cm^-3. While the mean concentrations were indicative of general trends, we found that the determinants of exposure (meteorology, traffic parameters, route, fuel type, exhaust treatment technologies, cabin ventilation, filtration, deposition, UFP penetration) exhibited marked variability and mode-dependence, such that it is not necessarily appropriate to rank modes in order of exposure without detailed consideration of these factors. Ten in-transit health effects studies have been conducted and their results indicate that UFP exposure during commuting can elicit acute effects in both healthy and health-compromised individuals. We suggest that future work should focus on further defining the contribution of in-transit UFP exposure to total UFP exposure, exploring its specific health effects and investigating exposures in the developing world. Keywords: air pollution; transport modes; acute health effects; travel; public transport

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Public transportation is an environment with great potential for applying innovative ubiquitous computing services to enhance user experiences. This paper provides the underpinning rationale for research that will be looking at how real-time passenger information system deployed by transit authorities can provide a core platform to improve commuters’ user experiences during all stages of their journey. The proposal builds on this platform to inform the design and development of innovative social media, mobile computing and geospatial information applications, with the hope to create fun and meaningful experiences for passengers during their everyday travel. Furthermore, we present the findings of our pilot study that aims to offer a better understanding of passengers’ activities and social interactions during their daily commute.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

High Speed Rail (HSR) is rapidly gaining popularity worldwide as a safe and efficient transport option for long-distance travel. Designed to win market shares from air transport, HSR systems optimise their productivity between increasing speeds and station spacing to offer high quality service and gain ridership. Recent studies have investigated the effects that the deployment of HSR infrastructure has on spatial distribution and the economic development of cities and regions. Findings appear mostly positive at higher geographical scales, where HSR links connect major urban centres several hundred kilometres apart and already well positioned within a national or international context. Also, at the urban level, studies have shown regeneration and concentration effects around HSR station areas with positive returns on city’s image and economy. However, doubts persist on the effects of HSR at an intermediate scale, where the accessibility trade off on station spacing limits access to many small and medium agglomerations. Thereby, their ability to participate in the development opportunities facilitated by HSR infrastructure is significantly reduced. The locational advantages deriving from transport improvements appear contrasting especially in regions that tend to have a polycentric structure, where cities may present greater accessibility disparities between those served by HSR and those left behind. This thesis fits in this context where intermediate and regional cities do not directly enjoy the presence of an HSR station while having an existing or planned proximate HSR corridor. With the aim of understanding whether there might be a solution to this apparent incongruity, the research investigates strategies to integrate HSR accessibility at the regional level. While current literature recommends to commit with ancillary investments to the uplift of station areas and the renewal of feeder systems, I hypothesised the interoperability between the HSR and the conventional networks to explore the possibilities offered by mixed traffic and infrastructure sharing. Thus, I developed a methodology to quantify the exchange of benefits deriving from this synergistic interaction. In this way, it was possible to understand which level of service quality offered by alternative transit strategies best facilitates the distribution of accessibility benefits for areas far from actual HSR stations. Therefore, strategies were selected for their type of service capable of regional extensions and urban penetrations, while incorporating a combination of specific advantages (e.g. speed, sub-urbanity, capacity, frequency and automation) in order to emulate HSR quality with increasingly efficient services. The North-eastern Italian macro region was selected as case study to ground the research offering concurrently a peripheral polycentric metropolitan form, the presence of a planned HSR corridor with some portions of HSR infrastructure implementation, and the project to develop a suburban rail service extended regionally. Results show significant distributive potential, in terms of network effects produced in relation with HSR, in increasing proportions for all the strategies considered: a regional metro rail strategy (abbreviated RMR), a regional high speed rail strategy (abbreviated RHSR), a regional light rail transit (abbreviated LRT) strategy, and a non-stopping continuous railway system (abbreviated CRS) strategy. The provision of additional tools to value HSR infrastructure against its accessibility benefits and their regional distribution through alternative strategies beyond the actual HSR stations, would have great implications, both politically and technically, in moving towards new dimensions of HSR evaluation and development.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Floods are the most common type of disaster globally, responsible for almost 53,000 deaths in the last decade alone (23:1 low- versus high-income countries). This review assessed recent epidemiological evidence on the impacts of floods on human health. Published articles (2004–2011) on the quantitative relationship between floods and health were systematically reviewed. 35 relevant epidemiological studies were identified. Health outcomes were categorized into short- and long-term and were found to depend on the flood characteristics and people's vulnerability. It was found that long-term health effects are currently not well understood. Mortality rates were found to increase by up to 50% in the first year post-flood. After floods, it was found there is an increased risk of disease outbreaks such as hepatitis E, gastrointestinal disease and leptospirosis, particularly in areas with poor hygiene and displaced populations. Psychological distress in survivors (prevalence 8.6% to 53% two years post-flood) can also exacerbate their physical illness. There is a need for effective policies to reduce and prevent flood-related morbidity and mortality. Such steps are contingent upon the improved understanding of potential health impacts of floods. Global trends in urbanization, burden of disease, malnutrition and maternal and child health must be better reflected in flood preparedness and mitigation programs.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Enterococci are versatile Gram-positive bacteria that can survive under extreme conditions. Most enterococci are non-virulent and found in the gastrointestinal tract of humans and animals. Other strains are opportunistic pathogens that contribute to a large number of nosocomial infections globally. Epidemiological studies demonstrated a direct relationship between the density of enterococci in surface waters and the risk of swimmer-associated gastroenteritis. The distribution of infectious enterococcal strains from the hospital environment or other sources to environmental water bodies through sewage discharge or other means, could increase the prevalence of these strains in the human population. Environmental water quality studies may benefit from focusing on a subset of Enterococcus spp. that are consistently associated with sources of faecal pollution such as domestic sewage, rather than testing for the entire genus. E. faecalis and E. faecium are potentially good focal species for such studies, as they have been consistently identified as the dominant Enterococcus spp. in human faeces and sewage. On the other hand enterococcal infections are predominantly caused by E. faecalis and E. faecium. The characterisation of E. faecalis and E. faecium is important in studying their population structures, particularly in environmental samples. In developing and implementing rapid, robust molecular genotyping techniques, it is possible to more accurately establish the relationship between human and environmental enterococci. Of particular importance, is to determine the distribution of high risk enterococcal clonal complexes, such as E. faecium clonal complex 17 and E. faecalis clonal complexes 2 and 9 in recreational waters. These clonal complexes are recognized as particularly pathogenic enterococcal genotypes that cause severe disease in humans globally. The Pimpama-Coomera watershed is located in South East Queensland, Australia and was investigated in this study mainly because it is used intensively for agriculture and recreational purposes and has a strong anthropogenic impact. The primary aim of this study was to develop novel, universally applicable, robust, rapid and cost effective genotyping methods which are likely to yield more definitive results for the routine monitoring of E. faecalis and E. faecium, particularly in environmental water sources. To fullfill this aim, new genotyping methods were developed based on the interrogation of highly informative single nucleotide polymorphisms (SNPs) located in housekeeping genes of both E. faecalis and E. faecium. SNP genotyping was successfully applied in field investigations of the Coomera watershed, South-East Queensland, Australia. E. faecalis and E. faecium isolates were grouped into 29 and 23 SNP profiles respectively. This study showed the high longitudinal diversity of E. faecalis and E. faecium over a period of two years, and both human-related and human-specific SNP profiles were identified. Furthermore, 4.25% of E. faecium strains isolated from water was found to correspond to the important clonal complex-17 (CC17). Strains that belong to CC17 cause the majority of hospital outbreaks and clinical infections globally. Of the six sampling sites of the Coomera River, Paradise Point had the highest number of human-related and human-specific E. faecalis and E. faecium SNP profiles. The secondary aim of this study was to determine the antibiotic-resistance profiles and virulence traits associated with environmental E. faecalis and E. faecium isolates compared to human pathogenic E. faecalis and E. faecium isolates. This was performed to predict the potential health risks associated with coming into contact with these strains in the Coomera watershed. In general, clinical isolates were found to be more resistant to all the antibiotics tested compared to water isolates and they harbored more virulence traits. Multi-drug resistance was more prevalent in clinical isolates (71.18% of E. faecalis and 70.3 % of E. faecium) compared to water isolates (only 5.66 % E. faecium). However, tetracycline, gentamicin, ciprofloxacin and ampicillin resistance was observed in water isolates. The virulence gene esp was the most prevalent virulence determinant observed in clinical isolates (67.79% of E. faecalis and 70.37 % of E. faecium), and this gene has been described as a human-specific marker used for microbial source tracking (MST). The presence of esp in water isolates (16.36% of E. faecalis and 19.14% of E. faecium) could be indicative of human faecal contamination in these waterways. Finally, in order to compare overall gene expression between environmental and clinical strains of E. faecalis, a comparative gene hybridization study was performed. The results of this investigation clearly demonstrated the up-regulation of genes associated with pathogenicity in E. faecalis isolated from water. The expression study was performed at physiological temperatures relative to ambient temperatures. The up-regulation of virulence genes demonstrates that environmental strains of E. faecalis can pose an increased health risk which can lead to serious disease, particularly if these strains belong to the virulent CC17 group. The genotyping techniques developed in this study not only provide a rapid, robust and highly discriminatory tool to characterize E. faecalis and E. faecium, but also enables the efficient identification of virulent enterococci that are distributed in environmental water sources.