In Cognitive Radio Networks (CRNs), Primary Users (PUs) can share their idle spectra with Secondary Users (SUs) under certain mechanisms. In this paper, we propose a distributed-centralized and incentive-aware spectrum sharing scheme for the multiple-PU scenario, which introduces a Random Leader who is elected randomly from SUs or PUs. The distributed aspect of our scheme lies in that it requir...

Cognitive radio is an efficient technique for realization of dynamic spectrum access. Since in the cognitive radio network (CRN) environment, the secondary users (SUs) are susceptible to the random jammers, the security issue of the SU’s channel access becomes crucial for the CRN framework. The rapidly varying spectrum dynamics of CRN along with the jammer’s actions leads to challenging scenari...

Cognitive radio technology enables unlicensed users (secondary users, SUs) to access the unused licensed spectrum which is allocated to primary users (PUs). In the literature, there are three traditional spectrum sharing paradigms that enable SUs to access the licensed spectrum. These access techniques include underlay, overlay and spectrum trading, and have their own drawbacks. To combat these...

The effect of endurance run training on outward K+ currents with rapidly inactivating (I(to)) and sustained or slowly inactivating (I(sus)) characteristics was examined in left ventricular (LV) cardiocytes isolated from sedentary (Sed) and treadmill-trained (Tr) female Sprague-Dawley rats. Isolated LV cardiocytes were used in whole cell patch-clamp studies to characterize whole cell I(to) and I...

BACKGROUND AND PURPOSE Approximately 23% of Australian hospitals provide Stroke Units (SUs). Evidence suggests that clinical outcomes are better in SUs than with conventional care. Reasons may include greater adherence to processes of care (PoC). The primary hypothesis was that adherence to selected PoC is greater in SUs than in other acute care models. METHODS Prospective, multicenter, singl...

In cognitive radio networks (CRNs), secondary users (SUs) may employ network coding to pursue higher throughput. However, as SUs must vacate the spectrum when it is accessed by primary users (PUs), the available transmission time of SUs is usually uncertain, i.e., SUs do not know how long the idle state can last. Meanwhile, existing network coding strategies generally adopt a block-based transm...

Cognitive radio (CR) is a promising technology that brings about remarkable improvement in spectrum utilization. To tackle the hidden terminal problem, cooperative spectrum sensing (CSS) which benefits from the spatial diversity has been studied extensively. Since CSS is vulnerable to the attacks initiated by malicious secondary users (SUs), several secure CSS schemes based on Dempster-Shafer t...

OBJECTIVE To investigate the learning on the management of resources of the Unified Health System (Sistema Único de Saúde - SUS) and its interfaces with private institutions in the radiology residency program of Escola Paulista de Medicina - Universidade Federal de São Paulo, in order to improve radiologists' training. MATERIALS AND METHODS Exploratory research with quantitative and qualitati...

Brazil is a country of continental dimensions, with many social inequalities. The latter are reflected on its health system, which comprises a large public component called SUS, a small paid health insurance component and a third very small private component, in which patients pay personally for medical services. Seventy five percent of the population depends on SUS, which thus far does not pro...

OBJECTIVE To analyze judicial requests for medications that are covered by the pharmaceutical assistance components of the Sistema Único de Saúde (SUS - Brazilian Unified Health System). METHODS We analyzed 81 judicial requests for medications in the State of São Paulo between 2005 and 2009. The details of these cases were obtained electronically from the Court of Justice of the State of São ...