Single-Rate and Multi-Rate Multi-Service Systems for Next Generation and Beyond Communications

To flexibly support diverse communication requirements (e.g., throughput, latency, massive connection, etc.) for the next generation wireless communications, one viable solution is to divide the system bandwidth into several service subbands, each for a different type of service. In such a multi-service (MS) system, each service has its optimal frame structure while the services are isolated by subband filtering. In this paper, a framework for multi-service (MS) system is established based on subband filtered multi-carrier (SFMC) modulation. We consider both single-rate (SR) and multi-rate (MR) signal processing as two different MS-SFMC implementations, each having different performance and computational complexity. By comparison, the SR system outperforms the MR system in terms of performance while the MR system has a significantly reduced computational complexity than the SR system. Numerical results show the effectiveness of our analysis and the proposed systems. These proposed SR and MR MS-SFMC systems provide guidelines for next generation wireless system frame structure optimization and algorithm design

Effects of Dietary Sodium Intake on Blood Flow Regulation During Exercise in Salt Resistant Individuals

PURPOSE: Dietary sodium intake guidelines is ≤2,300 mg/day, yet is exceeded by 90% of Americans. This study examined the impact of a high sodium diet on blood flow regulation during exercise. METHODS: Six males (25 ± 2 years) consumed dietary sodium intake guidelines for two weeks, with one week salt-capsule supplemented (HS: 6,900 mg/day of sodium) and the other week placebo-capsule supplemented (LS: 2,300 mg/day of sodium). At the end of each week, peripheral hemodynamic measurements [blood flow (BF), shear rate (SR), and flow mediated dilation (FMD)/SR)] of the brachial and superficial femoral artery were taken during handgrip (HG) and plantar flexion (PF) exercise, respectively. Each exercise workload was 3 minutes and progressed by 8 kilograms until exhaustion. RESULTS: There were no differences between LS and HS in blood pressure (82 ± 4 v 80 ± 5 mmHg; p = 0.3) or heart rate (56 ± 6 v 59 ± 10 bpm; p = 0.4). HG and PF exercise increased BF, SR, and FMD/SR across workload (p \u3c 0.03 for all), but no difference between diets (p \u3e 0.05 for all). CONCLUSION: Despite previous reports that HS impairs resting vascular function, this study revealed that peripheral vascular function and blood flow regulation during exercise is not impacted by a HS diet.https://scholarscompass.vcu.edu/gradposters/1082/thumbnail.jp

Sustainability management : insights from the viable system model

A review of current literature on sustainability standards reveals a significant gap between their adoption and the implementation of sustainability into every level of the organisation. In this paper, it is argued that in order to overcome this challenge, an appropriate model of an organisation is needed. The Viable System Model (VSM) is proposed as such a model and, in order to illustrate this argument, it is used to interpret the ISO 26000 standard on Social Responsibility (SR). First, the VSM theory is introduced and presented by modelling the hypothetical company Widget Co. Then, the clauses of ISO 26000 are mapped on the Widget Co. model, together with detailed descriptions and examples on the organisational and managerial implications of its adopting the standard's guidelines. The result is the identification of generic SR functions that need to be performed by the various organisational governance systems, as well as their dynamic interrelations, thus clarifying implementation issues. Moreover, by identifying different SR management layers, VSM is suggested as a way forward to develop an integration model for SR issues and respective sustainability tools. Finally, a discussion is given on the implications of using this approach to integrate sustainability standards and the way this research contributes to recent developments in sustainability research

How do systematic reviews incorporate risk of bias assessments into the synthesis of evidence? A methodological study

Background: Systematic reviews (SRs) are expected to critically appraise included studies and privilege those at lowest risk of bias (RoB) in the synthesis. This study examines if and how critical appraisals inform the synthesis and interpretation of evidence in SRs.<p></p> Methods: All SRs published in March–May 2012 in 14 high-ranked medical journals and a sample from the Cochrane library were systematically assessed by two reviewers to determine if and how: critical appraisal was conducted; RoB was summarised at study, domain and review levels; and RoB appraisals informed the synthesis process.<p></p> Results: Of the 59 SRs studied, all except six (90%) conducted a critical appraisal of the included studies, with most using or adapting existing tools. Almost half of the SRs reported critical appraisal in a manner that did not allow readers to determine which studies included in a review were most robust. RoB assessments were not incorporated into synthesis in one-third (20) of the SRs, with their consideration more likely when reviews focused on randomised controlled trials. Common methods for incorporating critical appraisals into the synthesis process were sensitivity analysis, narrative discussion and exclusion of studies at high RoB. Nearly half of the reviews which investigated multiple outcomes and carried out study-level RoB summaries did not consider the potential for RoB to vary across outcomes.<p></p> Conclusions: The conclusions of the SRs, published in major journals, are frequently uninformed by the critical appraisal process, even when conducted. This may be particularly problematic for SRs of public health topics that often draw on diverse study designs

A description of the methodology used in an overview of reviews to evaluate evidence on the treatment, harms, diagnosis/ classification, prognosis and outcomes used in the management of neck pain

Background: Neck Pain (NP) is a common musculoskeletal disorder and the literature provides conflicting evidence about its management. Objective: To describe the methodology used to conduct an overview of reviews (OvR) and to characterize the distribution and risk of bias profiles across the evidence for all areas of NP management. Methods: Standard systematic review (SR) methodology was employed. MEDLINE, CINAHL, EMBASE, ILC, Cochrane CENTRAL, and LILACS were searched from 2000 to March 2012; Narrative and SR and clinical practice guidelines (CPG) evaluating the efficacy of treatment (benefits and harms), diagnosis/classification, prognosis, and outcomes were eligible. For treatment, articles were limited to SRs from 2005 forward. Risk of bias of SR was assessed with the AMSTAR; the AGREE II was used to critically appraise the CPGs. Results: From 2476 articles, 508 were eligible for full text screening. A total of 341 articles were included. Treatment (n=117) had the greatest yield. Other clinical areas had less literature (diagnosis=54, prognosis=16, outcomes=27, harms=16). There were no SR for classification and narrative reviews were problematic for this topic. There was great overlap across different databases within each clinical area except for those for outcome measures. Risk of bias assessment using the AMSTAR of eligible SRs showed a similar trend across different clinical areas. Conclusion: A summary of methods used to review the literature in five clinical areas of NP management have been described. The challenges of selecting and synthesizing eligible articles in an OvR required customized solutions across different areas of clinical focus

CEUS LI-RADS: a pictorial review

Contrast-enhanced ultrasound (CEUS) greatly improved the diagnostic accuracy of US in the detection and characterization of focal liver lesions (FLLs), and it is suggested and often included in many international guidelines as an important diagnostic tool in the imaging work-up of cirrhotic patients at risk for developing hepatocellular carcinoma (HCC). In particular, CEUS Liver Imaging Reporting and Data System (LI-RADS) provides standardized terminology, interpretation, and reporting for the diagnosis of HCC. The aim of this pictorial essay is to illustrate CEUS features of nodules discovered at US in cirrhotic liver according to LI-RADS categorization