1,559 research outputs found

    Impact of content storage and retrieval mechanisms on the performance of vehicular delay-tolerant networks

    Get PDF
    “Copyright © [2010] IEEE. Reprinted from 18th International Conference on Software, Telecommunications and Computer Networks (SoftCOM 2010). ISBN: 978-1-4244-8663-2 . This material is posted here with permission of the IEEE. Internal or personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution must be obtained from the IEEE by writing to [email protected]. By choosing to view this document, you agree to all provisions of the copyright laws protecting it.”Vehicular Delay-Tolerant Networking (VDTN) is a new disruptive network architecture based on the concept of delay tolerant networks (DTNs). VDTNs handle non-real time applications using vehicles to carry messages on their buffers, relaying them only when a proper contact opportunity occurs. Therefore, the network performance is directly affected by the storage capacity and message retrieving of intermediate nodes. This paper proposes a suitable content storage and retrieval (CSR) mechanism for VDTN networks. This CSR solution adds additional information on control labels of the setup message associated to the corresponding data bundle (aggregated traffic) that defines and applies caching and forwarding restrictions on network traffic (data bundles). Furthermore, this work presents a performance analysis and evaluation of CSR mechanisms over a VDTN application scenario, using a VDTN testbed. This work presents the comparison of the network behavior and performance using two DTN routing protocols, Epidemic and Spray and Wait, with and without CSR mechanisms. The results show that CSR mechanisms improve the performance of VDTN networks significantly.Part of this work has been supported by the Instituto de Telecomunicações, Next Generation Networks and Applications Group (NetGNA), Portugal in the framework of the Project VDTN@Lab, and by the Euro-NF Network of Excellence from the Seventh Framework Programme of EU, in the framework of the Specific Joint Research Project VDTN

    Residential indoor exposure to fine and ultrafine particulate air pollution in association with blood pressure and subclinical central haemodynamic markers of cardiovascular risk among healthy adults living in Perth, Western Australia

    Get PDF
    Despite that large percentages of individual daily time is spent in the home, few studies have examined the relationship between indoor particulate matter (PM) exposure in residential settings with subclinical indicators of cardiovascular risk. This cross-sectional study investigated associations between exposure to fine (PM2.5) and ultrafine (UFP) PM in domestic indoor environments, with central blood pressure (BP) and component BP measures (pulse pressure, augmented pressure [AP], augmentation index [AIx], mean arterial pressure, pulse wave velocity [PWV]) in 40 non-smoking, otherwise healthy adults (58% women) living in Perth, Western Australia. Overall, in adjusted models, an interquartile range (IQR) increase in PM2.5 was associated with a 3.2 mmHg (95% confidence interval [CI]: 0.99, 5.45) higher diastolic BP, and a 1.8 mmHg lower AP (95%CI: − 3.63, − 0.01) and 0.4 m/s PWV (95%CI: − 0.80, − 0.08), respectively. For the UFP fraction, an IQR increase was associated with a 5.2% higher AIx (95%CI: 0.51, 9.97) and a 0.6 m/s lower PWV (95%CI: − 1.00, − 0.11). When stratified by sex, higher UFP concentrations were associated with higher DBP and lower PWV among women. Among men, higher UFP concentrations were associated with lower AP. Exposure to domestic indoor fine and ultrafine PM was associated with preclinical indicators of cardiovascular risk and some of these relationships were affected by sex. These findings contribute important evidence linking low-level residential indoor PM exposure with measurable impacts on cardiovascular physiology and may inform preventative recommendations as part of risk profiles for susceptible individuals

    Food consumption of Sri Lankan adults: an appraisal of serving characteristics

    Get PDF
    Objective: The main aim of the present study was to identify food consumption in Sri Lankan adults based on serving characteristics. Design: Cross-sectional study. Fruits, vegetables, starch, meat, pulses, dairy products and added sugars in the diet were assessed with portion sizes estimated using standard methods. Setting: Twelve randomly selected clusters from the Sri Lanka Diabetes and Cardiovascular Study. Subjects: Six hundred non-institutionalized adults. Results: The daily intake of fruit (0.43), vegetable (1.73) and dairy (0.39) portions were well below national recommendations. Only 3.5 % of adults consumed the recommended 5 portions of fruits and vegetables/d; over a third of the population consumed no dairy products and fewer than 1 % of adults consumed 2 portions/d. In contrast, Sri Lankan adults consumed over 14 portions of starch and 3.5 portions of added sugars daily. Almost 70 % of those studied exceeded the upper limit of the recommendations for starch intake. The total daily number of meat and pulse portions was 2.78. Conclusions: Dietary guidelines emphasize the importance of a balanced and varied diet; however, a substantial proportion of the Sri Lankan population studied failed to achieve such a recommendation. Nutrition-related diseases in the country may be closely correlated with unhealthy eating habits

    Associations between sub-clinical markers of cardiometabolic risk and exposure to residential indoor air pollutants in healthy adults in Perth, Western Australia: A study protocol

    Get PDF
    © 2019 by the authors. Licensee MDPI, Basel, Switzerland. Background: A growing body of epidemiological and clinical evidence has implicated air pollution as an emerging risk factor for cardiometabolic disease. Whilst individuals spend up to two-thirds of daily time in their domestic residential environment, very few studies have been designed to objectively measure the sub-clinical markers of cardiometabolic risk with exposure to domestic indoor air pollutants. This cross-sectional study aims to investigate associations between the components of domestic indoor air quality and selected sub-clinical cardiometabolic risk factors in a cohort of healthy adults living in Perth,Western Australia. Methods: One hundred and eleven non-smoking adults (65% female) living in non-smoking households who were aged between 35-69 years were recruited for the project. Study subjects were invited to participate in all sections of the study, which included: Domestic indoor air monitoring along with the concurrent 24 h ambulatory monitoring of peripheral and central blood pressure and measures of central hemodynamic indices, standardized questionnaires on aspects relating to current health status and the domestic environment, a 24 h time-activity diary during the monitoring period, and clinic-based health assessment involving collection of blood and urine biomarkers for lipid and glucose profiles, as well as measures of renal function and an analysis of central pulse wave and pulse wave velocity. Results: This study provides a standardized approach to the study of sub-clinical cardiometabolic health effects that are related to the exposure to indoor air pollution. Conclusion: The findings of this study may provide direction for future research that will further contribute to our understanding of the relationship that exists between indoor air pollution and sub-clinical markers of cardiometabolic risk

    Postprandial Energy Metabolism in the Regulation of Body Weight: Is there a Mechanistic Role for Dietary Calcium?

    Get PDF
    There has been much interest in the mechanisms by which calcium may attenuate weight gain or accelerate body fat loss. This review focuses on postprandial energy metabolism and indicates that dietary calcium increases whole body fat oxidation after single and multiple meals. There is, as yet, no conclusive evidence for a greater diet induced thermogenesis, an increased lipolysis or suppression of key lipogenic enzyme systems. There is however convincing evidence that higher calcium intakes promote a modest energy loss through increased fecal fat excretion. Overall, there is a role for dietary calcium in human energy metabolism. Future studies need to define threshold intakes for metabolic and gastrointestinal outcomes

    Diagnosis and management of Guillain-Barré syndrome in ten steps

    Get PDF
    Guillain-Barré syndrome (GBS) is a rare, but potentially fatal, immune-mediated disease of the peripheral nerves and nerve roots that is usually triggered by infections. The incidence of GBS can therefore increase during outbreaks of infectious diseases, as was seen during the Zika virus epidemics in 2013 in French Polynesia and 2015 in Latin America. Diagnosis and management of GBS can be complicated as its clinical presentation and disease course are heterogeneous, and no international clinical guidelines are currently available. To support clinicians, especially in the context of an outbreak, we have developed a globally applicable guideline for the diagnosis and management of GBS. The guideline is based on current literature and expert consensus, and has a ten-step structure to facilitate its use in clinical practice. We first provide an introduction to the diagnostic criteria, clinical variants and differential diagnoses of GBS. The ten steps then cover early recognition and diagnosis of GBS, admission to the intensive care unit, treatment indication and selection, monitoring and treatment of disease progression, prediction of clinical course and outcome, and management of complications and sequelae

    QUALITY OF LIFE OF PATIENTS WITH METABOLIC SYNDROME IS IMPROVED AFTER WHOLE BODY VIBRATION EXERCISES

    Get PDF
    Background: Whole body vibration exercises (WBVE) improve the quality of life (QoL) of different populations. Metabolic syndrome patients (MetS) may be favored by physical activity. Questionnaires are used to assess the QoL. The aim was to evaluate the QoL of patients with MetS that have undergone WBVE with a brief WHOQOL (WHOQOL-BREF). Material and Methods: MetS patients were randomly divided into three groups: (i) control group (CG), (ii) treated with WBVE once per week (WBVE1) and (iii) treated with WBVE twice per week (WBVE2). In the first session, the patient was sat in a chair in front of the platform with the feet on its base in 3 peak to peak displacements (2.5, 5.0 and 7.5 mm) and frequency of 5 Hz was used. From the second to the last session, patients were subjected to the same protocol, however they were standing on the base of the platform and the frequency was increased up to 14 Hz. The patients fulfilled the WHOQOL-BREF before the first and after the last sessions. Cronbach coefficients were determined to each domain of the WHOQOL-BREF and test Wilcoxon (
    corecore