Dynamic Power Management for Reactive Stream Processing on the SCC Tiled Architecture

This article is distributed under the terms of the Creative Commons Attribution 4.0 International License(http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.Dynamic voltage and frequency scaling} (DVFS) is a means to adjust the computing capacity and power consumption of computing systems to the application demands. DVFS is generally useful to provide a compromise between computing demands and power consumption, especially in the areas of resource-constrained computing systems. Many modern processors support some form of DVFS. In this article we focus on the development of an execution framework that provides light-weight DVFS support for reactive stream-processing systems (RSPS). RSPS are a common form of embedded control systems, operating in direct response to inputs from their environment. At the execution framework we focus on support for many-core scheduling for parallel execution of concurrent programs. We provide a DVFS strategy for RSPS that is simple and lightweight, to be used for dynamic adaptation of the power consumption at runtime. The simplicity of the DVFS strategy became possible by sole focus on the application domain of RSPS. The presented DVFS strategy does not require specific assumptions about the message arrival rate or the underlying scheduling method. While DVFS is a very active field, in contrast to most existing research, our approach works also for platforms like many-core processors, where the power settings typically cannot be controlled individually for each computational unit. We also support dynamic scheduling with variable workload. While many research results are provided with simulators, in our approach we present a parallel execution framework with experiments conducted on real hardware, using the SCC many-core processor. The results of our experimental evaluation confirm that our simple DVFS strategy provides potential for significant energy saving on RSPS.Peer reviewe

Arterial remodeling and hemodynamics in carotid stents: a prospective duplex ultrasound study over 2 years

AbstractObjectiveThis study was undertaken to study negative and positive arterial remodeling processes within self-expanding carotid stents, their interaction, and the resulting changes in hemodynamics over 2 years, with duplex ultrasound scanning.Subjects and methodsOne hundred twelve consecutive patients with 121 successfully stented carotid arteries were examined with color-coded duplex ultrasound scanning the day after the stent procedure and at 3, 6, 12, and 24 months of follow-up. The stent diameters at the proximal, middle, and distal regions, and the maximal neointimal thickness (B-mode) and hemodynamic parameters were recorded. Pre-interventional plaques were assigned to three types: soft, fibrous, and largely calcified.ResultsThe diameters of the self-expanding stents steadily increased over 2 years (positive arterial remodeling), from (mean ± SD) 5.80 ± 0.89 mm to 6.77 ± 0.98 mm in the proximal stent area, from 3.51 ± 0.76 mm to 4.92 ± 0.89 mm in the middle stent area, and from 3.7 ± 0.5 mm to 4.68 ± 0.61 mm in the distal stent area (P < .001). Stent expansion was most marked in the middle stent area, depending on the type of pre-interventional plaque. The extent in stent expansion was more in soft than in fibrous and calcified plaques (P < .001). Neointimal thickness increased up to 12 months, and stabilized thereafter. The mean (± SD) neointimal thickness at 3, 6, 12, and 24 months was 0.61 ± 0.28 mm, 0.97 ± 0.39 mm, 1.06 ± 0.36 mm, and 1.12 ± 0.38 mm, respectively. These complex interactions resulted in the dominance of negative remodeling secondary to neointimal proliferation, with an increased flow ratio during the first year, from 1.16 ± 0.37 at day 1 to 1.23 ± 0.46 at 3 months, 1.67 ± 1.37 at 6 months, and 1.57 ± 0.70 at 12 months (P < .001), followed by a tendency to decrease as a result of stent expansion thereafter (flow ratio at 24 months, 1.49 ± 0.70). Two of 121 stents (1.6%) had recurrent stenosis that required a secondary procedure.ConclusionsNeointimal proliferation or negative arterial remodeling prevails up to 12 months, and may give rise to rare stent recurrent stenosis. Stent expansion reduces this effect in the first year, and dominates in the second year. This might contribute to the good mid-term outcome of carotid stenting. Poor stent expansion in heavily calcified plaques calls for primary surgical management

Associations between nailfold capillary aberrations and autoantibodies in children and adults with Raynaud’s phenomenon

Objective To characterise associations between individual nailfold capillary aberrations with autoantibodies in a cross-sectional study on children and adults with Raynaud’s phenomenon (RP).Methods Consecutive children and adults with RP and without previously known connective tissue disease (CTD) systemically underwent nailfold capillaroscopy and laboratory tests for the presence of antinuclear antibodies (ANA). The prevalence of individual nailfold capillary aberrations and ANA was assessed, and the associations between individual nailfold capillary aberrations and ANA were analysed separately in children and adolescents.Results In total, 113 children (median age 15 years) and 2858 adults (median age 48 years) with RP and without previously known CTD were assessed. At least one nailfold capillary aberration was detected in 72 (64%) of included children and in 2154 (75%) of included adults with RP (children vs adults p&lt;0.05). An ANA titre ≥1:80, ≥1:160 or≥1:320 was observed in 29%, 21% or 16% of included children, and in 37%, 27% or 24% of screened adults, respectively. While the occurrence of individual nailfold capillary aberrations was related to the presence of an ANA titre of ≥1:80 in adults (reduced capillary density, avascular fields, haemorrhages, oedema, ramifications, dilations and giant capillaries: each p&lt;0.001), no comparable association between nailfold capillary aberrations and ANA was observed in children with RP without previously known CTD.Conclusion In contrast to adults, the association between nailfold capillary aberrations and ANA might be less pronounced in children. Further studies are warranted to validate these observations in children with RP

Guidance for the Management of Patients with Vascular Disease or Cardiovascular Risk Factors and COVID-19: Position Paper from VAS-European Independent Foundation in Angiology/Vascular Medicine.

COVID-19 is also manifested with hypercoagulability, pulmonary intravascular coagulation, microangiopathy, and venous thromboembolism (VTE) or arterial thrombosis. Predisposing risk factors to severe COVID-19 are male sex, underlying cardiovascular disease, or cardiovascular risk factors including noncontrolled diabetes mellitus or arterial hypertension, obesity, and advanced age. The VAS-European Independent Foundation in Angiology/Vascular Medicine draws attention to patients with vascular disease (VD) and presents an integral strategy for the management of patients with VD or cardiovascular risk factors (VD-CVR) and COVID-19. VAS recommends (1) a COVID-19-oriented primary health care network for patients with VD-CVR for identification of patients with VD-CVR in the community and patients' education for disease symptoms, use of eHealth technology, adherence to the antithrombotic and vascular regulating treatments, and (2) close medical follow-up for efficacious control of VD progression and prompt application of physical and social distancing measures in case of new epidemic waves. For patients with VD-CVR who receive home treatment for COVID-19, VAS recommends assessment for (1) disease worsening risk and prioritized hospitalization of those at high risk and (2) VTE risk assessment and thromboprophylaxis with rivaroxaban, betrixaban, or low-molecular-weight heparin (LMWH) for those at high risk. For hospitalized patients with VD-CVR and COVID-19, VAS recommends (1) routine thromboprophylaxis with weight-adjusted intermediate doses of LMWH (unless contraindication); (2) LMWH as the drug of choice over unfractionated heparin or direct oral anticoagulants for the treatment of VTE or hypercoagulability; (3) careful evaluation of the risk for disease worsening and prompt application of targeted antiviral or convalescence treatments; (4) monitoring of D-dimer for optimization of the antithrombotic treatment; and (5) evaluation of the risk of VTE before hospital discharge using the IMPROVE-D-dimer score and prolonged post-discharge thromboprophylaxis with rivaroxaban, betrixaban, or LMWH