1,359 research outputs found

    Availability Evaluation of Service Function Chains Under Different Protection Schemes

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    Network Function Virtualization (NFV) calls for a new resource management approach where virtualized network functions (VNFs) replace traditional network hardware appliances. Thanks to NFV, operators are given a much greater flexibility, as these VNFs can be deployed as virtual nodes and chained together to form Service Function Chains (SFCs). An SFC represents a set of dedicated virtualized resources deployed to provide a certain service to the consumer. One of its most important performance requirements is availability. In this paper, the availability achieved by SFCs is evaluated analytically, by modelling several protection schemes and given different availability values for the network components. The cost of each protection scheme, based on its network resource consumption, is also taken into account. Extensive numerical results are reported, considering various SFC characteristics, such as availability requirements, number of NFV nodes and availability values of network components. The lowest-cost protection strategy, in terms of number of occupied network components, which meets availability requirement, is identified. Our analysis demonstrates that, in most cases, resource-greedy protection schemes, such as end-to-end protection, can be replaced by less aggressive schemes, even when availability requirements are in the order of five or six nines, depending on the number of elements in the service function chain

    Implementation of sample pooling procedure using a rapid sars-cov-2 diagnostic real-time pcr test performed prior to hospital admission of people with intellectual disabilities

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    Reliability, accuracy, and timeliness of diagnostic testing for SARS-CoV-2 infection have allowed adequate public health management of the disease, thus notably helping the timely mapping of viral spread within the community. Furthermore, the most vulnerable populations, such as people with intellectual disability and dementia, represent a high-risk group across multiple dimensions, including a higher prevalence of pre-existing conditions, lower health maintenance, and a propensity for rapid community spread. This led to an urgent need for reliable in-house rapid testing to be performed prior to hospital admission. In the present study, we describe a pooling procedure in which oropharyngeal and nasopharyngeal swabs for SARS-CoV-2 detection (performed prior to hospital admission using rapid RT-PCR assay) are pooled together at the time of sample collection. Sample pooling (groups of 2–4 samples per tube) allowed us to significantly reduce response times, consumables, and personnel costs while maintaining the same test sensitivity

    Experimental Testing of Dynamically Optimized Photoelectron Beams

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    We discuss the design of and initial results from an experiment in space-charge dominated beam dynamics which explores a new regime of high-brightness electron beam generation at the SPARC (located at INFN-LNF, Frascati) photoinjector. The scheme under study employs the natural tendency in intense electron beams to configure themselves to produce a uniform density, giving a nearly ideal beam from the viewpoint of space charge-induced emittance. The experiments are aimed at testing the marriage of this idea with a related concept, emittance compensation, We show that the existing infrastructure at SPARC is nearly ideal for the proposed tests, and that this new regime of operating photoinjector may be the preferred method of obtaining highest brightness beams with lower energy spread. We discuss the design of the experiment, including developing of a novel time-dependent, aerogel-based imaging system. This system has been installed at SPARC, and first evidence for nearly uniformly filled ellipsoidal charge distributions recorded

    Safety of aortic aneurysm repair 8 weeks after percutaneous coronary intervention for coronary artery disease: a cohort study

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    Guidelines advice against dual antiplatelet therapy (DAPT) discontinuation less than 12 months after percutaneous coronary intervention with drug-eluting stents (DES-PCI). However, any delay of necessary surgery in patients with descending thoracic (DTA) or abdominal aortic aneurysm (AAA), treated by DES-PCI, increases the risk of aneurysm rupture/dissection. We evaluated the safety of 8-week waiting time between DES-PCI and endovascular aortic repair (EVAR). 1152 consecutive patients with coronary artery disease (CAD) needing elective DTA or AAA repair were enrolled and divided into two groups. Group A included 830 patients treated by DES-PCI for significant CAD who underwent surgery 8 weeks after implantation. Group B included 322 patients treated by DES-PCI at least 6 months before with no residual significant CAD and treated by elective EVAR. Groups were compared according to a composite of death, myocardial infarction, stent thrombosis, cerebrovascular events and bleeding. No aneurysm rupture/dissection occurred while waiting for surgery. Hospital averse events occurred in 6.2% (52/830) group A patients versus 6.5% (21/322) group B patients (p = 0.8). Mortality was 0.7% (6/830) in group A and 0.9% (3/322) in group B (p = 0.7). Multivariate predictors of events were triple vessel DES-PCI (p 3 stents implanted (p 30 mm (p = 0.02). Eight weeks of waiting after DES-PCI in addition to an adequate management of DAPT were safe in terms of cardiac morbidity and bleeding complications. No aneurysm rupture occurred in the interval before surgery

    ANMCO/SIC/SICI-GISE/SICCH Executive Summary of Consensus Document on Risk Stratification in elderly patients with aortic stenosis before surgery or transcatheter aortic valve replacement

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    Aortic stenosis is one of the most frequent valvular diseases in developed countries, and its impact on public health resources and assistance is increasing. A substantial proportion of elderly people with severe aortic stenosis is not eligible to surgery because of the advanced age, frailty, and multiple co-morbidities. Transcatheter aortic valve implantation (TAVI) enables the treatment of very elderly patients at high or prohibitive surgical risk considered ineligible for surgery and with an acceptable life expectancy. However, a significant percentage of patients die or show no improvement in quality of life (QOL) in the follow-up. In the decision-making process, it is important to determine: (i) whether and how much frailty of the patient influences the risk of procedures; (ii) how the QOL and the individual patient's survival are influenced by aortic valve disease or from other associated conditions; and (iii) whether a geriatric specialist intervention to evaluate and correct frailty or other diseases with their potential or already manifest disabilities can improve the outcome of surgery or TAVI. Consequently, in addition to risk stratification with conventional tools, a number of factors including multi-morbidity, disability, frailty, and cognitive function should be considered, in order to assess the expected benefit of both surgery and TAVI. The pre-operative optimization through a multidisciplinary approach with a Heart Team can counteract the multiple damage (cardiac, neurological, muscular, respiratory, and kidney) that can potentially aggravate the reduced physiological reserves characteristic of frailty. The systematic application in clinical practice of multidimensional assessment instruments of frailty and cognitive function in the screening and the adoption of specific care pathways should facilitate this task
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