89 research outputs found
Security, usability, and biometric authentication scheme for electronic voting using multiple keys
We propose electronic voting authentication scheme, which is a key management mechanism for electronic voting system intended to limit the number of attacks on a polling station and strengthen the security control. The motivation is to diversify security requirements of messages exchanged between polling stations. There are different types of messages exchanged between polling stations and each type of message has different security needs. A security mechanism developed on the basis of a single key is not enough to ensure the diverse security needs of voting network. In electronic voting authentication scheme, every polling station is responsible to support three different types of keys. These are global key, pairwise key, and individual key. The global keys are public keys shared with all polling stations in the voting network. The pairwise key can be used for communication with polling stations. Individual keys will be used for communication with the server. To ensure authentication of local broadcast, electronic voting authentication scheme uses one-way key chains in a well-organized way. The support of source authentication is a visible advantage of this scheme. We examine the authentication of electronic voting authentication scheme on numerous attack models. The measurement demonstrates that electronic voting authentication scheme is very operative in protecting against numerous elegant attacks such as wormhole attack, Sybil attack, and HELLO Flood attack. The proposed system is evaluated and the results demonstrate that the proposed system is practical and secure as compared to the direct recording electronic and manual systems
One-year efficacy and safety of routine prasugrel in patients with acute coronary syndromes treated with percutaneous coronary intervention
Objective: To investigate 1‑year outcomes with routine prasugrel treatment after acute coronary syndrome (ACS) in a large-scale registry. Methods: The Rijnmond Collective Cardiology Research registry is a prospective, observational study that enrolled 4,258 consecutive ACS patients treated with percutaneous coronary intervention (PCI) with 1‑year follow-up. Patients received prasugrel as first-choice antiplatelet agent, except for increased bleeding risk patients in which clopidogrel was recommended. Events were validated by an independent clinical endpoint committee. Results: A total number of 2,677 patients received prasugrel at discharge after the index event. Eighty-one percent of the target population was on prasugrel treatment at hospital discharge. At 1 year, the primary endpoint, a composite of all-cause mortality and myocardial infarction, occurred in 2.4% of patients receiving prasugrel. All-cause mortality occurred in 1.0%, myocardial infarction in 1.5%, target-vessel revascularisation in 3.1%, stent thrombosis in 0.6%, and stroke in 0.5% of the patients treated with prasugrel. Thrombolysis in Myocardial Infarction defined major bleeding episodes not related to coronary artery bypass grafting were observed in 1.4% of patients receiving prasugrel. Conclusions: In routine practice, a tailored approach of prasugrel prescription in ACS patients undergoing PCI, resulted in low ischaemic and low bleeding rates up to 1 year post PCI
Twin-Component Near-Pareto Routing Optimization for AANETs in the North-Atlantic Region Relying on Real Flight Statistics
Integrated ground-air-space (IGAS) networks intrinsically amalgamate terrestrial and non-terrestrial communication techniques in support of universal connectivity across the globe. Multi-hop routing over the IGAS networks has the potential to provide long-distance highly directional connections in the sky. For meeting the latency and reliability requirements of in-flight connectivity, we formulate a multi-objective multi-hop routing problem in aeronautical ad hoc networks (AANETs) for concurrently optimizing multiple end-to-end performance metrics
in terms of the total delay and the throughput. In contrast to single-objective optimization problems that may have a unique optimal solution, the problem formulated is a multi-objective combinatorial optimization problem (MOCOP), which generally has a set of trade-off solutions, called the Pareto optimal set. Due to the discrete structure of the MOCOP formulated, finding the Pareto optimal set becomes excessively complex for large-scale networks. Therefore, we employ a multi-objective evolutionary algorithm (MOEA), namely the classic NSGA-II for generating an approximation of the Pareto optimal set. Explicitly, with the intrinsic parallelism of MOEAs, the MOEA employed starts with a set of candidate solutions for creating and reproducing new solutions via genetic operators. Finally, we evaluate the MOCOP
formulated for different networks generated both from simulated
data as well as from real historical flight data. Our simulation results demonstrate that the utilized MOEA has the potential of finding the Pareto optimal solutions for small-scale networks, while also finding a set of high-performance nondominated solutions for large-scale networks
Minimum-Delay Routing for Integrated Aeronautical Ad Hoc Networks Relying on Real Flight Data in the North-Atlantic Region
Relying on multi-hop communication techniques, aeronautical ad hoc networks (AANETs) seamlessly integrate ground base stations (BSs) and satellites into aircraft communications for enhancing the on-demand connectivity of planes in the air. The goal of the paper is to assess the performance of the classic shortest-path routing algorithm in the context of the real flight data collected in the North-Atlantic Region. Specifically, in this integrated AANET context we investigate the shortest-path routing problem with the objective of minimizing the total delay of the in-flight connection from the ground BS subject to certain minimum-rate constraints for all selected links in support of lowlatency and high-speed services. Inspired by the best-first search and priority queue concepts, we model the problem formulated
by a weighted digraph and find the optimal route based on the shortest-path algorithm. Our simulation results demonstrate that
aircraft-aided multi-hop communications are capable of reducing
the total delay of satellite communications, when relying on real
historical flight data
The benefits of statins in people without established cardiovascular disease but with cardiovascular risk factors: meta-analysis of randomised controlled trials
Objectives To investigate whether statins reduce all cause mortality and major coronary and cerebrovascular events in people without established cardiovascular disease but with cardiovascular risk factors, and whether these effects are similar in men and women, in young and older (>65 years) people, and in people with diabetes mellitus
Current discharge management of acute coronary syndromes: Data from the Rijnmond Collective Cardiology Research (CCR) study
Background Medical discharge management of acute coronary syndromes (ACS) remains suboptimal outside randomised trials and constitutes an essential quality benchmark for ACS. We sought to evaluate the rates of key guideline-recommended pharmacological agents after ACS and characteristics associated with optimal treatment at discharge. Methods The Rijnmond Collective Cardiology Research (CCR) registry is an ongoing prospective, observational study in the Netherlands that aims to enrol 4000 patients with ACS. We examined discharge and 1-month follow-up medication use among the first 1000 patients enrolled in the CCR registry. Logistic regression was performed to identify patient and hospital characteristics associated with collective guidelinerecommended pharmacotherapy at hospital discharge. Results At discharge, 94%of patients received aspirin, 100% thienopyridines, 80 % angiotensin-converting enzyme inhibitors/angiotensin-II receptor blockers, 87 % β-blockers, 96 % statins, and 65 % the combination of all 5 agents. STsegment elevation myocardial infarction, hypertension, hypercholesterolaemia, and enrolment in an interventional centre were positive independent predictors of 5-drug combination therapy at discharge. Negative independent predictors were unstable angina and advanced age. Conclusion Current data from the CCR registry reflect a high quality of care for ACS discharge management in the Rotterdam-Rijnmond region. However, potential still remains for further optimisation
Aortic distensibility and coronary artery bypass graft patency
<p>Abstract</p> <p>Background</p> <p>Aortic distensibility is an elasticity index of the aorta, and reflects aortic stiffness. Coronary artery disease has been found to be substantially associated with increased aortic stiffness. In this study we aimed to retrospectively analyze the association of angiographically determined aortic distensibility with the patency rates of coronary bypass grafts</p> <p>Methods</p> <p>The study was conducted in the Cardiology department of the Applied Research Centre for Health of Uludağ University. The coronary angiograms of 53 consecutive coronary bypass patients were analysed retrospectively. Aortic distensibility was calculated using the formula: 2 × (change in aortic diameter)/(diastolic aortic diameter) × (change in aortic pressure). The number of stenosed and patent bypass grafts and the patient characteristics like age, risk factors were noted.</p> <p>Results</p> <p>There were 44 male (83%) and 9 female (17%) cases. Eighteen cases had only one saphenous vein grafting. The number of cases with two, three and four saphenous grafting were 18, 11 and 1; respectively. In the control angiograms the number of cases with one, two, three and four saphenous vein graft obstruction were 15 (31.3%), 7 (14.6%), 1 (2.1%) and 1 (2.1%) respectively. The aortic distensibility did not differ in cases with and without saphenous graft occlusion (p > 0.05). Also left internal mammary artery (LIMA) graft patency was not related to the distensibility of the aorta (p > 0.05). We also evaluated the data for cut-off values of 50 and 70 mmHg of pulse pressure and did not see any significant difference between the groups in terms of saphenous or LIMA grafts.</p> <p>Conclusion</p> <p>In this study we failed to show association of angiographically determined aortic distensibility with coronary bypass graft patency in consecutive 53 patients with coronary artery bypass graft surgery (CABG).</p
Distinct cardioprotective mechanisms of immediate, early and delayed ischaemic postconditioning
Cardioprotection against ischaemia/reperfusion injury in mice can be achieved by delayed ischaemic postconditioning (IPost) applied as late as 30 min after the onset of reperfusion. We determined the efficacy of delayed IPost in a rat model of myocardial infarction (MI) and investigated potential underlying mechanisms of this phenomenon. Rats were subjected to 20, 30 or 45 min of coronary artery occlusion followed by 120 min of reperfusion (I/R). Immediate and early IPost included six cycles of I/R (10/10 s) applied 10 s or 10 min after reperfusion onset. In the second series of experiments, the rats were subjected to 30 min of coronary occlusion followed by IPost applied 10 s, 10, 30, 45 or 60 min after the onset of reperfusion. Immediate and early IPost (applied 10 s or 10 min of reperfusion) established cardioprotection only when applied after a period of myocardial ischaemia lasting 30 min. Delayed IPost applied after 30 or 45 min of reperfusion reduced infarct sizes by 36 and 41 %, respectively (both P < 0.01). IPost applied 60 min after reperfusion onset was ineffective. Inhibition of RISK pathway (administration of ERK1/2 inhibitor PD-98059 or PI3K inhibitor LY-294002) abolished cardioprotection established by immediate IPost but had no effect on cardioprotection conferred by early IPost. Blockade of SAFE pathway using JAK/STAT inhibitor AG490 had no effect on the immediate or early IPost cardioprotection. Blockade of mitochondrial KATP (mitoKATP) channels (with 5-Hydroxydecanoate) abolished cardioprotection achieved by immediate and early IPost, but had no effect on cardioprotection when IPost was applied 30 or 45 min into the reperfusion period. Immediate IPost increased phosphorylation of PI3K-AKT and ERK1/2. Early or delayed IPost had no effect on phosphorylation of PI3K-AKT, ERK1/2 or STAT3. These data show that in the rat model, delayed IPost confers significant cardioprotection even if applied 45 min after onset of reperfusion. Cardioprotection induced by immediate and early postconditioning involves recruitment of RISK pathway and/or mitoKATP channels, while delayed postconditioning appears to rely on a different mechanism
Fabrication Principles and Their Contribution to the Superior In Vivo Therapeutic Efficacy of Nano-Liposomes Remote Loaded with Glucocorticoids
We report here the design, development and performance of a novel formulation of liposome- encapsulated glucocorticoids (GCs). A highly efficient (>90%) and stable GC encapsulation was obtained based on a transmembrane calcium acetate gradient driving the active accumulation of an amphipathic weak acid GC pro-drug into the intraliposome aqueous compartment, where it forms a GC-calcium precipitate. We demonstrate fabrication principles that derive from the physicochemical properties of the GC and the liposomal lipids, which play a crucial role in GC release rate and kinetics. These principles allow fabrication of formulations that exhibit either a fast, second-order (t1/2 ∼1 h), or a slow, zero-order release rate (t1/2 ∼ 50 h) kinetics. A high therapeutic efficacy was found in murine models of experimental autoimmune encephalomyelitis (EAE) and hematological malignancies
Multi-analytical investigation into painting materials and techniques: the wall paintings of Abuna Yemata Guh church
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