927 resultados para peer-to-peer (P2P) computing


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Global climate change is one of the most significant environmental impacts at the moment. One central issue for the building and construction industry to address global climate change is the development of credible carbon labelling schemes for building materials. Various carbon labelling schemes have been developed for concrete due to its high contribution to global greenhouse gas (GHG) emissions. However, as most carbon labelling schemes adopt cradle-to-gate as system boundary, the credibility of the eco-label information may not be satisfactory because recent studies show that the use and end-of-life phases can have a significant impact on the life cycle GHG emissions of concrete in terms of carbonation, maintenance and rehabilitation, other indirect emissions, and recycling activities. A comprehensive review on the life cycle assessment of concrete is presented to holistically examine the importance of use and end-of-life phases to the life cycle GHG quantification of concrete. The recent published ISO 14067: Carbon footprint of products – requirements and guidelines for quantification and communication also mandates the use of cradle-to-grave to provide publicly available eco-label information when the use and end-of-life phases of concrete can be appropriately simulated. With the support of Building Information Modelling (BIM) and other simulation technologies, the contribution of use and end-of-life phases to the life cycle GHG emissions of concrete should not be overlooked in future studies.

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Computational optimisation of clinically important electrocardiogram signal features, within a single heart beat, using a Markov-chain Monte Carlo (MCMC) method is undertaken. A detailed, efficient data-driven software implementation of an MCMC algorithm has been shown. Initially software parallelisation is explored and has been shown that despite the large amount of model parameter inter-dependency that parallelisation is possible. Also, an initial reconfigurable hardware approach is explored for future applicability to real-time computation on a portable ECG device, under continuous extended use.

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Railhead is perhaps the highest stressed civil infrastructure due to the passage of heavily loaded wheels through a very small contact patch. The stresses at the contact patch cause yielding of the railhead material and wear. Many theories exist for the prediction of these mechanisms of continuous rails; this process in the discontinuous rails is relatively sparingly researched. Discontinuous railhead edges fail due to accumulating excessive plastic strains. Significant safety concern is widely reported as these edges form part of Insulated Rail Joints (IRJs) in the signalling track circuitry. Since Hertzian contact is not valid at a discontinuous edge, 3D finite element (3DFE) models of wheel contact at a railhead edge have been used in this research. Elastic–plastic material properties of the head hardened rail steel have been experimentally determined through uniaxial monotonic tension tests and incorporated into a FE model of a cylindrical specimen subject to cyclic tension load- ing. The parameters required for the Chaboche kinematic hardening model have been determined from the stabilised hysteresis loops of the cyclic load simulation and imple- mented into the 3DFE model. The 3DFE predictions of the plastic strain accumulation in the vicinity of the wheel contact at discontinuous railhead edges are shown to be affected by the contact due to passage of wheels rather than the magnitude of the loads the wheels carry. Therefore to eliminate this failure mechanism, modification to the contact patch is essential; reduction in wheel load cannot solve this problem.

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Australia is undergoing a critical demographic transition: the population is ageing. By 2050, one in four Australians will be older than 65 years and by 2031, the number of older Australians requiring residential aged care will increase 63%, to 1.4 million (ABS, 2005). In anticipation of this global demographic transition, the World Health Organisation has advocated ‘active ageing’, identifying health, participation and security as the three key factors that enhance quality of life for people as they age (WHO, 2002). While there is considerable discussion and acceptance of active ageing principles, little is known about the experience of ‘active ageing’ for older Australians who live in Residential Aged Care Facilities (RACF). This research addresses this knowledge gap by exploring the key facilitators and barriers to quality of life and active ageing in aged care from the perspective of aged care residents (n=12). To do this, the project documented the initial expectations and daily life experience of new residents living in a RACF over a one-year period. Combined with in-depth interviews and surveys, the project utilised Photovoice methodology - where participants used photography to record their lived experiences. The initial findings suggest satisfaction with living in aged care centers around five key themes; resident’s mental attitude to living in aged care, forming positive peer and staff relationships, self-determination and maintaining independence, opportunities to participate in interesting activities, and living in a safe and comfortable physical environment. This paper reports on the last of these five key themes, focusing on the role of design in facilitating quality of life, specifically: “living within these walls” – safety, comfort and the physical environment.

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Time series classification has been extensively explored in many fields of study. Most methods are based on the historical or current information extracted from data. However, if interest is in a specific future time period, methods that directly relate to forecasts of time series are much more appropriate. An approach to time series classification is proposed based on a polarization measure of forecast densities of time series. By fitting autoregressive models, forecast replicates of each time series are obtained via the bias-corrected bootstrap, and a stationarity correction is considered when necessary. Kernel estimators are then employed to approximate forecast densities, and discrepancies of forecast densities of pairs of time series are estimated by a polarization measure, which evaluates the extent to which two densities overlap. Following the distributional properties of the polarization measure, a discriminant rule and a clustering method are proposed to conduct the supervised and unsupervised classification, respectively. The proposed methodology is applied to both simulated and real data sets, and the results show desirable properties.

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During the early design stages of construction projects, accurate and timely cost feedback is critical to design decision making. This is particularly challenging for cost estimators, as they must quickly and accurately estimate the cost of the building when the design is still incomplete and evolving. State-of-the-art software tools typically use a rule-based approach to generate detailed quantities from the design details present in a building model and relate them to the cost items in a cost estimating database. In this paper, we propose a generic approach for creating and maintaining a cost estimate using flexible mappings between a building model and a cost estimate. The approach uses queries on the building design that are used to populate views, and each view is then associated with one or more cost items. The benefit of this approach is that the flexibility of modern query languages allows the estimator to encode a broad variety of relationships between the design and estimate. It also avoids the use of a common standard to which both designers and estimators must conform, allowing the estimator added flexibility and functionality to their work.

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Early full-term pregnancy is one of the most effective natural protections against breast cancer. To investigate this effect, we have characterized the global gene expression and epigenetic profiles of multiple cell types from normal breast tissue of nulliparous and parous women and carriers of BRCA1 or BRCA2 mutations. We found significant differences in CD44+ progenitor cells, where the levels of many stem cell-related genes and pathways, including the cell-cycle regulator p27, are lower in parous women without BRCA1/BRCA2 mutations. We also noted a significant reduction in the frequency of CD44+p27+ cells in parous women and showed, using explant cultures, that parity-related signaling pathways play a role in regulating the number of p27+ cells and their proliferation. Our results suggest that pathways controlling p27+ mammary epithelial cells and the numbers of these cells relate to breast cancer risk and can be explored for cancer risk assessment and prevention.

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This study demonstrates a novel method for testing the hypothesis that variations in primary and secondary particle number concentration (PNC) in urban air are related to residual fuel oil combustion at a coastal port lying 30 km upwind, by examining the correlation between PNC and airborne particle composition signatures chosen for their sensitivity to the elemental contaminants present in residual fuel oil. Residual fuel oil combustion indicators were chosen by comparing the sensitivity of a range of concentration ratios to airborne emissions originating from the port. The most responsive were combinations of vanadium and sulfur concentration ([S], [V]) expressed as ratios with respect to black carbon concentration ([BC]). These correlated significantly with ship activity at the port and with the fraction of time during which the wind blew from the port. The average [V] when the wind was predominantly from the port was 0.52 ng.m-3 (87%) higher than the average for all wind directions and 0.83 ng.m-3 (280%) higher than that for the lowest vanadium yielding wind direction considered to approximate the natural background. Shipping was found to be the main source of V impacting urban air quality in Brisbane. However, contrary to the stated hypothesis, increases in PNC related measures did not correlate with ship emission indicators or ship traffic. Hence at this site ship emissions were not found to be a major contributor to PNC compared to other fossil fuel combustion sources such as road traffic, airport and refinery emissions.

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Objectives To evaluate quality of care delivered to patients presenting to the emergency department (ED) with pain and managed by emergency nurse practitioners by measuring: 1) Evaluate time to analgesia from initial presentation 2) Evaluate time from being seen to next analgesia 3) Pain score documentation Background The delivery of quality care in the emergency department (ED) is emerging as one of the most important service indicators being measured by health services. Emergency nurse practitioner services are designed to improve timely, quality care for patients. One of the goals of quality emergency care is the timely and effective delivery of analgesia for patients. Timely analgesia is an important indicator of ED service performance. Methods A retrospective explicit chart review of 128 consecutive patients with pain and managed by emergency nurse practitioners was conducted. Data collected included demographics, presenting complaint, pain scores, and time to first dose of analgesia. Patients were identified from the ED Patient Information System (Cerner log) and data were extracted from electronic medical records Results Pain scores were documented in 67 (52.3%; 95% CI: 43.3-61.2) patients. The median time to analgesia from presentation was 60.5 (IQR 30-87) minutes, with 34 (26.6%; 95% CI: 19.1-35.1) patients receiving analgesia within 30 minutes of presentation to hospital. There were 22 (17.2%; 95% CI: 11.1-24.9) patients who received analgesia prior to assessment by a nurse practitioner. Among patients that received analgesia after assessment by a nurse practitioner, the median time to analgesia after assessment was 25 (IQR 12-50) minutes, with 65 (61.3%; 95% CI: 51.4-70.6) patients receiving analgesia within 30 minutes of assessment. Conclusions The majority of patients assessed by nurse practitioners received analgesia within 30 minutes after assessment. However, opportunities for substantial improvement in such times along with documentation of pain scores were identified and will be targeted in future research.

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Mutation of the BRAF gene is common in thyroid cancer. Follicular variant of papillary thyroid carcinoma is a variant of papillary thyroid carcinoma that has created continuous diagnostic controversies among pathologists. The aims of this study are to (1) investigate whether follicular variant of papillary thyroid carcinoma has a different pattern of BRAF mutation than conventional papillary thyroid carcinoma in a large cohort of patients with typical features of follicular variant of papillary thyroid carcinoma and (2) to study the relationship of clinicopathological features of papillary thyroid carcinomas with BRAF mutation. Tissue blocks from 76 patients with diagnostic features of papillary thyroid carcinomas (40 with conventional type and 36 with follicular variant) were included in the study. From these, DNA was extracted and BRAF V600E mutations were detected by polymerase chain reaction followed by restriction enzyme digestion and sequencing of exon 15. Analysis of the data indicated that BRAF V600E mutation is significantly more common in conventional papillary thyroid carcinoma (58% versus 31%, P = .022). Furthermore, the mutation was often noted in female patients (P = .017), in high-stage cancers (P = .034), and in tumors with mild lymphocytic thyroiditis (P = .006). We concluded that follicular variant of papillary thyroid carcinoma differs from conventional papillary thyroid carcinoma in the rate of BRAF mutation. The results of this study add further information indicating that mutations in BRAF play a role in thyroid cancer development and progression.

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Geminin was identified in Xenopus as a dual function protein involved in the regulation of DNA replication and neural differentiation. In Xenopus, Geminin acts to antagonize the Brahma (Brm) chromatin-remodeling protein, Brg1, during neural differentiation. Here, we investigate the interaction of Geminin with the Brm complex during Drosophila development. We demonstrate that Drosophila Geminin (Gem) interacts antagonistically with the Brm–BAP complex during wing development. Moreover, we show in vivo during wing development and biochemically that Brm acts to promote EGFR–Ras–MAPK signaling, as indicated by its effects on pERK levels, while Gem opposes this. Furthermore, gem and brm alleles modulate the wing phenotype of a Raf gain-of-function mutant and the eye phenotype of a EGFR gain-of-function mutant. Western analysis revealed that Gem over-expression in a background compromised for Brm function reduces Mek (MAPKK/Sor) protein levels, consistent with the decrease in ERK activation observed. Taken together, our results show that Gem and Brm act antagonistically to modulate the EGFR–Ras–MAPK signaling pathway, by affecting Mek levels during Drosophila development.

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Editorial: is it the time for railway industry to reinvent itself? Railway infrastructure plays a critical role in urban development, mobility, and economic growth of society. This focus issue of the Electronic Journal of Structural Engineering is devoted to a special theme, “Advances in Rail Track Infrastructure and Practice - ARTRP”. It contains articles, which were rigorously peer reviewed and accepted from a list of invited manuscripts that demonstrate significant innovation in the area of the structural engineering aspects of the rail track infrastructure...

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Despite the acknowledged importance of assessment in education, there has been minimal research into the preparation of preservice teachers for the important role of involving preservice teachers in marking, grading, moderating and providing feedback on student work. This article reports on a pilot project in which preservice teachers participated in an ongoing peer assessment and social moderation process in a dedicated course on assessment. The purpose of the project was to investigate specific ways in which key assessment processes can be effectively taught to preservice teachers. The research involved 96 preservice teachers who completed a Likert scale survey and free text responses to set questions. The results indicated that while preservice teachers valued the process, continual opportunities to learn the nature and purpose of essential assessment practices related to marking, grading, moderating and providing feedback are necessary to graduate competent and work-ready assessors.

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S. japonicum infection is believed to be endemic in 28 of the 80 provinces of the Philippines and the most recent data on schistosomiasis prevalence have shown considerable variability between provinces. In order to increase the efficient allocation of parasitic disease control resources in the country, we aimed to describe the small scale spatial variation in S. japonicum prevalence across the Philippines, quantify the role of the physical environment in driving the spatial variation of S. japonicum, and develop a predictive risk map of S. japonicum infection. Data on S. japonicum infection from 35,754 individuals across the country were geo-located at the barangay level and included in the analysis. The analysis was then stratified geographically for Luzon, the Visayas and Mindanao. Zero-inflated binomial Bayesian geostatistical models of S. japonicum prevalence were developed and diagnostic uncertainty was incorporated. Results of the analysis show that in the three regions, males and individuals aged ≥ 20 years had significantly higher prevalence of S. japonicum compared with females and children <5 years. The role of the environmental variables differed between regions of the Philippines. S. japonicum infection was widespread in the Visayas whereas it was much more focal in Luzon and Mindanao. This analysis revealed significant spatial variation in prevalence of S. japonicum infection in the Philippines. This suggests that a spatially targeted approach to schistosomiasis interventions, including mass drug administration, is warranted. When financially possible, additional schistosomiasis surveys should be prioritized to areas identified to be at high risk, but which were underrepresented in our dataset.

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This article assesses the extent to which the recently formulated Chinese concept of “Responsible Protection” (RP) offers a valuable contribution to the normative debate over R2P’s third pillar following the controversy over military intervention in Libya. While RP draws heavily on previous proposals such as the original 2001 ICISS report and Brazil’s “Responsibility while Protecting” (RwP), by amalgamating and re-packaging these earlier ideas in a more restrictive form the initiative represents a new and distinctive interpretation of R2P. However, some aspects of RP are framed too narrowly to provide workable guidelines for determining the permissibility of military intervention for civilian protection purposes, and should therefore be clarified and refined. Nevertheless, the Chinese proposal remains significant because it offers important insights into Beijing’s current stance on R2P. More broadly, China’s RP and Brazil’s RwP initiatives illustrate the growing willingness of rising, non-Western powers to assert their own normative preferences on sovereignty, intervention and global governance.