WorldWideScience

Sample records for qos provisioning recurrent

  1. QoS mapping algorithm for ETE QoS provisioning

    Science.gov (United States)

    Wu, Jian J.; Foster, Gerry

    2002-08-01

    End-to-End (ETE) Quality of Service (QoS) is critical for next generation wireless multimedia communication systems. To meet the ETE QoS requirements, Universal Mobile Telecommunication System (UMTS) requires not only meeting the 3GPP QoS requirements [1-2] but also mapping external network QoS classes to UMTS QoS classes. There are four Quality of Services (QoS) classes in UMTS; they are Conversational, Streaming, Interactive and Background. There are eight QoS classes for LAN in IEEE 802.1 (one reserved). ATM has four QoS categories. They are Constant Bit Rate (CBR) - highest priority, short queue for strict Cell Delay Variation (CDV), Variable Bit Rate (VBR) - second highest priority, short queues for real time, longer queues for non-real time, Guaranteed Frame Rate (GFR)/ Unspecified Bit Rate (UBR) with Minimum Desired Cell Rate (MDCR) - intermediate priority, dependent on service provider UBR/ Available Bit Rate (ABR) - lowest priority, long queues, large delay variation. DiffServ (DS) has six-bit DS codepoint (DSCP) available to determine the datagram's priority relative to other datagrams and therefore, up to 64 QoS classes are available from the IPv4 and IPv6 DSCP. Different organisations have tried to solve the QoS issues from their own perspective. However, none of them has a full picture for end-to-end QoS classes and how to map them among all QoS classes. Therefore, a universal QoS needs to be created and a new set of QoS classes to enable end-to-end (ETE) QoS provisioning is required. In this paper, a new set of ETE QoS classes is proposed and a mappings algorithm for different QoS classes that are proposed by different organisations is given. With our proposal, ETE QoS mapping and control can be implemented.

  2. SDN-based QoS Aware Network Service Provisioning

    DEFF Research Database (Denmark)

    Caba, Cosmin Marius; Soler, José

    2015-01-01

    One of the applicability areas of SDN is for creating services for dynamic provisioning of network resources with strict QoS requirements. The research available in this field focuses mainly on the service logic implemented over the functionality of the SDN Controller (SDNC). However, there is much...... to be covered regarding the specific mechanisms used by the SDNC to enforce the QoS in the data plane devices. To this end, the current paper proposes a data plane QoS architecture, together with the invariants that have to be maintained by the SDNC in order to ensure predictable QoS for the network services....... More specifically, the paper will look into on demand provisioning of Virtual Circuits (VCs) with specific QoS, based on the SDN paradigm. The aim is to analyze and compare the strategies for network resources management for two cases: a coarse granular and a fine granular VC provisioning service...

  3. An agent-based QoS provisioning mechanism for WDM optical networks

    Science.gov (United States)

    Ouyang, Yong; Zeng, Qingji; Yue, Ling

    2004-04-01

    This paper addresses QoS provisioning mechanisms in the WDM optical networks. With the appearance of metropolitan optical network, a hierarchical metro and wide area optical network will be envisioned in the near future. This hierarchical optical transport network is often divided into optical domains by geography, administration and technology, which usually employ different QoS routing algorithms and policies. To provide end-to-end optical QoS is becoming a new challenge for the optical network design. In this paper, we first give an overview of issues on the QoS provisioning in data, control and management planes of the WDM optical network. And then three provisioning approaches are analyzed and compared. Finally, we propose an agent-based hybrid centralized/distributed QoS provisioning mechanism based on the concept of domain agent. This agent-based hybrid mechanism employs centralized approach in the domain and distributed approach between domains. It offers scalability and intra-domain optimal QoS routing. It also keeps independence and interoperability between domains.

  4. Towards Internet QoS provisioning based on generic distributed QoS adaptive routing engine.

    Science.gov (United States)

    Haikal, Amira Y; Badawy, M; Ali, Hesham A

    2014-01-01

    Increasing efficiency and quality demands of modern Internet technologies drive today's network engineers to seek to provide quality of service (QoS). Internet QoS provisioning gives rise to several challenging issues. This paper introduces a generic distributed QoS adaptive routing engine (DQARE) architecture based on OSPFxQoS. The innovation of the proposed work in this paper is its undependability on the used QoS architectures and, moreover, splitting of the control strategy from data forwarding mechanisms, so we guarantee a set of absolute stable mechanisms on top of which Internet QoS can be built. DQARE architecture is furnished with three relevant traffic control schemes, namely, service differentiation, QoS routing, and traffic engineering. The main objective of this paper is to (i) provide a general configuration guideline for service differentiation, (ii) formalize the theoretical properties of different QoS routing algorithms and then introduce a QoS routing algorithm (QOPRA) based on dynamic programming technique, and (iii) propose QoS multipath forwarding (QMPF) model for paths diversity exploitation. NS2-based simulations proved the DQARE superiority in terms of delay, packet delivery ratio, throughput, and control overhead. Moreover, extensive simulations are used to compare the proposed QOPRA algorithm and QMPF model with their counterparts in the literature.

  5. Towards Internet QoS Provisioning Based on Generic Distributed QoS Adaptive Routing Engine

    Directory of Open Access Journals (Sweden)

    Amira Y. Haikal

    2014-01-01

    Full Text Available Increasing efficiency and quality demands of modern Internet technologies drive today’s network engineers to seek to provide quality of service (QoS. Internet QoS provisioning gives rise to several challenging issues. This paper introduces a generic distributed QoS adaptive routing engine (DQARE architecture based on OSPFxQoS. The innovation of the proposed work in this paper is its undependability on the used QoS architectures and, moreover, splitting of the control strategy from data forwarding mechanisms, so we guarantee a set of absolute stable mechanisms on top of which Internet QoS can be built. DQARE architecture is furnished with three relevant traffic control schemes, namely, service differentiation, QoS routing, and traffic engineering. The main objective of this paper is to (i provide a general configuration guideline for service differentiation, (ii formalize the theoretical properties of different QoS routing algorithms and then introduce a QoS routing algorithm (QOPRA based on dynamic programming technique, and (iii propose QoS multipath forwarding (QMPF model for paths diversity exploitation. NS2-based simulations proved the DQARE superiority in terms of delay, packet delivery ratio, throughput, and control overhead. Moreover, extensive simulations are used to compare the proposed QOPRA algorithm and QMPF model with their counterparts in the literature.

  6. Integration of QoS provisioning in home and access networks

    DEFF Research Database (Denmark)

    Popov, Mikhail; Gavler, A.; Sköldström, P.

    2010-01-01

    Approaches for QoS provisioning using UPnP for home networks and GMPLS for access networks are described. A solution for interworking the UPnP and the GMPLS at the residential gateway is proposed.......Approaches for QoS provisioning using UPnP for home networks and GMPLS for access networks are described. A solution for interworking the UPnP and the GMPLS at the residential gateway is proposed....

  7. Cross Layer QoS Provisioning in Home Networks

    DEFF Research Database (Denmark)

    Wang, Jiayuan; Brewka, Lukasz Jerzy; Ruepp, Sarah Renée

    2011-01-01

    This paper introduces an innovative QoS provisioning scheme in home networks, by utilizing Optical Wireless (OW) MAC specification proposed by Home Gigabit Access Project (OMEGA) project. The specification is characterized by its resource reservation protocol and the use of Time Division Multiple...... Access (TDMA). By adopting OW MAC to the widely supported Universal Plug and Play – Quality of Service (UPnP-QoS) Architecture in the simulated home domain, algorithms for cross layer mapping QoS requirements are proposed. Compared to utilizing WLAN MAC, our scheme is able to provide guaranteed Qo......S levels to streams with different priorities, especially to delay-sensitive services. Efficiencies of the algorithms and network performance are validated by analyzing the results collected from OPNET simulation models....

  8. Performance Enhancements of UMTS networks using end-to-end QoS provisioning

    DEFF Research Database (Denmark)

    Wang, Haibo; Prasad, Devendra; Teyeb, Oumer

    2005-01-01

    This paper investigates the end-to-end(E2E) quality of service(QoS) provisioning approaches for UMTS networks together with DiffServ IP network. The effort was put on QoS classes mapping from DiffServ to UMTS, Access Control(AC), buffering and scheduling optimization. The DiffServ Code Point (DSCP......) was utilized in the whole UMTS QoS provisioning to differentiate different type of traffics. The overall algorithm was optimized to guarantee the E2E QoS parameters of each service class, especially for realtime applications, as well as to improve the bandwidth utilization. Simulation shows that the enhanced...

  9. McMAC: Towards a MAC Protocol with Multi-Constrained QoS Provisioning for Diverse Traffic in Wireless Body Area Networks

    OpenAIRE

    Monowar, Muhammad; Hassan, Mohammad; Bajaber, Fuad; Al-Hussein, Musaed; Alamri, Atif

    2012-01-01

    The emergence of heterogeneous applications with diverse requirements for resource-constrained Wireless Body Area Networks (WBANs) poses significant challenges for provisioning Quality of Service (QoS) with multi-constraints (delay and reliability) while preserving energy efficiency. To address such challenges, this paper proposes McMAC, a MAC protocol with multi-constrained QoS provisioning for diverse traffic classes in WBANs. McMAC classifies traffic based on their multi-constrained QoS de...

  10. QoS Provisioning Techniques for Future Fiber-Wireless (FiWi Access Networks

    Directory of Open Access Journals (Sweden)

    Martin Maier

    2010-04-01

    Full Text Available A plethora of enabling optical and wireless access-metro network technologies have been emerging that can be used to build future-proof bimodal fiber-wireless (FiWi networks. Hybrid FiWi networks aim at providing wired and wireless quad-play services over the same infrastructure simultaneously and hold great promise to mitigate the digital divide and change the way we live and work by replacing commuting with teleworking. After overviewing enabling optical and wireless network technologies and their QoS provisioning techniques, we elaborate on enabling radio-over-fiber (RoF and radio-and-fiber (R&F technologies. We describe and investigate new QoS provisioning techniques for future FiWi networks, ranging from traffic class mapping, scheduling, and resource management to advanced aggregation techniques, congestion control, and layer-2 path selection algorithms.

  11. Statistical Delay QoS Provisioning for Energy-Efficient Spectrum-Sharing Based Wireless Ad Hoc Sensor Networks

    Directory of Open Access Journals (Sweden)

    Yichen Wang

    2016-01-01

    Full Text Available In this paper, we develop the statistical delay quality-of-service (QoS provisioning framework for the energy-efficient spectrum-sharing based wireless ad hoc sensor network (WAHSN, which is characterized by the delay-bound violation probability. Based on the established delay QoS provisioning framework, we formulate the nonconvex optimization problem which aims at maximizing the average energy efficiency of the sensor node in the WAHSN while meeting PU’s statistical delay QoS requirement as well as satisfying sensor node’s average transmission rate, average transmitting power, and peak transmitting power constraints. By employing the theories of fractional programming, convex hull, and probabilistic transmission, we convert the original fractional-structured nonconvex problem to the additively structured parametric convex problem and obtain the optimal power allocation strategy under the given parameter via Lagrangian method. Finally, we derive the optimal average energy efficiency and corresponding optimal power allocation scheme by employing the Dinkelbach method. Simulation results show that our derived optimal power allocation strategy can be dynamically adjusted based on PU’s delay QoS requirement as well as the channel conditions. The impact of PU’s delay QoS requirement on sensor node’s energy efficiency is also illustrated.

  12. McMAC: towards a MAC protocol with multi-constrained QoS provisioning for diverse traffic in Wireless Body Area Networks.

    Science.gov (United States)

    Monowar, Muhammad Mostafa; Hassan, Mohammad Mehedi; Bajaber, Fuad; Al-Hussein, Musaed; Alamri, Atif

    2012-11-12

    The emergence of heterogeneous applications with diverse requirements for resource-constrained Wireless Body Area Networks (WBANs) poses significant challenges for provisioning Quality of Service (QoS) with multi-constraints (delay and reliability) while preserving energy efficiency. To address such challenges, this paper proposes McMAC,a MAC protocol with multi-constrained QoS provisioning for diverse traffic classes in WBANs. McMAC classifies traffic based on their multi-constrained QoS demands and introduces a novel superframe structure based on the "transmit-whenever-appropriate"principle, which allows diverse periods for diverse traffic classes according to their respective QoS requirements. Furthermore, a novel emergency packet handling mechanism is proposedto ensure packet delivery with the least possible delay and the highest reliability. McMAC is also modeled analytically, and extensive simulations were performed to evaluate its performance. The results reveal that McMAC achieves the desired delay and reliability guarantee according to the requirements of a particular traffic class while achieving energy efficiency.

  13. An adaptive distributed admission approach in Bluetooth network with QoS provisions

    DEFF Research Database (Denmark)

    Son, L.T.; Schiøler, Henrik; Madsen, Ole Brun

    2002-01-01

    In this paper, a method of adaptive distributed admission with end-to-end Quality of Service (QoS) provisions for real time and non real time tra°cs in Blue-tooth networks is highlighted, its mathematic background is analyzed and a simulation with bursty tra°c sources, Interrupted Bernoulli Process...... (IBP), is carried out. The simulation results show that the performance of Bluetooth network is improved when applying the distributed admission method...

  14. McMAC: Towards a MAC Protocol with Multi-Constrained QoS Provisioning for Diverse Traffic in Wireless Body Area Networks

    Directory of Open Access Journals (Sweden)

    Muhammad Mostafa Monowar

    2012-11-01

    Full Text Available The emergence of heterogeneous applications with diverse requirements forresource-constrained Wireless Body Area Networks (WBANs poses significant challengesfor provisioning Quality of Service (QoS with multi-constraints (delay and reliability whilepreserving energy efficiency. To address such challenges, this paper proposes McMAC,a MAC protocol with multi-constrained QoS provisioning for diverse traffic classes inWBANs. McMAC classifies traffic based on their multi-constrained QoS demands andintroduces a novel superframe structure based on the "transmit-whenever-appropriate"principle, which allows diverse periods for diverse traffic classes according to their respectiveQoS requirements. Furthermore, a novel emergency packet handling mechanism is proposedto ensure packet delivery with the least possible delay and the highest reliability. McMACis also modeled analytically, and extensive simulations were performed to evaluate itsperformance. The results reveal that McMAC achieves the desired delay and reliabilityguarantee according to the requirements of a particular traffic class while achieving energyefficiency.

  15. Adaptive QoS provision for IEEE 802.16e BWA networks based on cross-layer design

    Directory of Open Access Journals (Sweden)

    Kuo GS

    2011-01-01

    Full Text Available Abstract This article proposes an integrated framework for adaptive QoS provision in IEEE 802.16e broadband wireless access networks based on cross-layer design. On one hand, an efficient admission control (AC algorithm is proposed along with a semi-reservation scheme to guarantee the connection-level QoS. First, to guarantee the service continuity for handoff connections and resource efficiency, our semi-reservation scheme considers both users' handoff probability and average resource consumption together, which effectively avoids resource over-reservation and insufficient reservation. For AC, a new/handoff connection is accepted only when the target cell has enough resource to afford both instantaneous and average resource consumption to meet the average source rate request. On the other hand, a joint resource allocation and packet scheduling scheme is designed to provide packet-level QoS guarantee in term of "QoS rate", which can ensure fairness for the services with identical priority level in case of bandwidth shortage. Particularly, an enhanced bandwidth request scheme is designed to reduce unnecessary BR delay and redundant signaling overhead caused by the existing one in IEEE 802.16e, which further improves the packet-level QoS performance and resource efficiency for uplink transmission. Simulation results show that the proposed approach not only balances the tradeoff among connection blocking rate, connection dropping rate, and connection failure rate, but also achieves low mean packet dropping rate (PDR, small deviation of PDR, and low QoS outage rate. Moreover, high resource efficiency is ensured.

  16. QoS Self-Provisioning and Interference Management for Co-Channel Deployed 3G Femtocells

    DEFF Research Database (Denmark)

    Kolding, Troels; Ochal, Pawel; Jørgensen, Niels T.K.

    2013-01-01

    A highly efficient self-provisioning interference management scheme is derived for 3G Home Node-Bs (HNB). The proposed scheme comprises self-adjustment of the HNB transmission parameters to meet the targeted QoS (quality of service) requirements in terms of downlink and uplink guaranteed minimum ...... live 3G high-speed packet access (HSPA) HNB field-trials, confirming the validity of major simulation results and assumptions....

  17. Novel Adaptive QoS Framework for Integrated UMTS/WLAN Environment

    Directory of Open Access Journals (Sweden)

    T. Shuminoski

    2013-06-01

    Full Text Available Since Quality of Service (QoS provisioning for multimedia traffic in integrated Wireless and Mobile Networks is becoming an increasingly important objective, in this paper we introduce a novel concept of an adaptive QoS cross-layer framework. The Adaptive QoS framework is proven via novel simulation results in integrated environment with UMTS and IEEE 802.11 networks. The aim of our novel framework is presenting a new module that shall provide the best QoS and lower cost for a given service using one or more wireless technologies in a given time. The analysis of simulation results has shown superior performances with a high level of QoS provisioning in a variety of network conditions. The performance of Adaptive QoS algorithm is evaluated using ns-miracle augmented with our dual-mode Mobile Equipments (MEs and using statistical analysis.

  18. A New Resources Provisioning Method Based on QoS Differentiation and VM Resizing in IaaS

    Directory of Open Access Journals (Sweden)

    Rongdong Hu

    2015-01-01

    Full Text Available In order to improve the host energy efficiency in IaaS, we proposed an adaptive host resource provisioning method, CoST, which is based on QoS differentiation and VM resizing. The control model can adaptively adjust control parameters according to real time application performance, in order to cope with changes in load. CoST takes advantage of the fact that different types of applications have different sensitivity degrees to performance and cost. It places two different types of VMs on the same host and dynamically adjusts their sizes based on the load forecasting and QoS feedback. It not only guarantees the performance defined in SLA, but also keeps the host running in energy-efficient state. Real Google cluster trace and host power data are used to evaluate the proposed method. Experimental results show that CoST can provide performance-sensitive application with a steady QoS and simultaneously speed up the overall processing of performance-tolerant application by 20~66%. The host energy efficiency is significantly improved by 7~23%.

  19. QoS frameworks for Multimedia Traffic in Mobile Adhoc Networks: A Comparative Review

    Directory of Open Access Journals (Sweden)

    S. Soni

    2017-06-01

    Full Text Available MANETs (Mobile Adhoc Networks has gained an increased interest by the research community. Regular intelligent exchanges of multimedia will be typical in MANET, though the extended motivation on QoS (Quality of Service. However, various properties of the discussed QoS framework are provisioned for QoS as a challenging concern. Providing QoS provisioning is, to a great degree, challenging in MANETs in view of bouncing correspondences, center point movability and nonattendance of central coordination. Thus, most of the research has focused on giving QoS guarantees in MANETs coordinating traditions. Though huge numbers of QoS coordinating procedures have been proposed in composing, focusing on different QoS estimations yet none of the prescribed or discussed frameworks achieves a universal course of action. There exist several genuine necessary research areas of focus such as QoS metric assurance and cost limit layout, source level scheduling framework and QoS coordinating. In this paper, working and connecting of various QoS frameworks for MANETs is investigated throughout several veritable focus areas of research. After a comparative review, it is concluded that there is still a good scope of research for proposing a QoS framework for MANETs which could have cross-layer advantages, resource reservation, connection admission control, multi-constrained QoS parameters, hard QoS assurance, proactive routing advantages etc.

  20. A Toolkit For Storage Qos Provisioning For Data-Intensive Applications

    Directory of Open Access Journals (Sweden)

    Renata Słota

    2012-01-01

    Full Text Available This paper describes a programming toolkit developed in the PL-Grid project, named QStorMan, which supports storage QoS provisioning for data-intensive applications in distributed environments. QStorMan exploits knowledge-oriented methods for matching storage resources to non-functional requirements, which are defined for a data-intensive application. In order to support various usage scenarios, QStorMan provides two interfaces, such as programming libraries or a web portal. The interfaces allow to define the requirements either directly in an application source code or by using an intuitive graphical interface. The first way provides finer granularity, e.g., each portion of data processed by an application can define a different set of requirements. The second method is aimed at legacy applications support, which source code can not be modified. The toolkit has been evaluated using synthetic benchmarks and the production infrastructure of PL-Grid, in particular its storage infrastructure, which utilizes the Lustre file system.

  1. UPnP QoS and queuing in home networks

    DEFF Research Database (Denmark)

    Brewka, Lukasz Jerzy; Wessing, Henrik; Dittmann, Lars

    2010-01-01

    The QoS provisioning in home networks is being more often considered for future use cases, where mulitple high bandwidth flows are accomodated in the home environment. This paper investigates chosen characteristics of one of the home network control and management protocol suites, namely UPn......P. Using network modeling tools, we evaluate UPnP QoS architecture and its resource management influence on the end-to-end packet delay characteristics for different scheduling approaches....

  2. Adaptive Radio Resource Allocation in Hierarchical QoS Scheduling for IEEE 802.16 Systems

    DEFF Research Database (Denmark)

    Wang, Hua; Dittmann, Lars

    2007-01-01

    Future mobile communication systems such as IEEE 802.16 are expected to deliver a variety of multimedia services with diverse QoS requirements. To guarantee the QoS provision, appropriate scheduler architecture and scheduling algorithms have to be carefully designed. In this paper, we propose...

  3. SLA-aware differentiated QoS in elastic optical networks

    Science.gov (United States)

    Agrawal, Anuj; Vyas, Upama; Bhatia, Vimal; Prakash, Shashi

    2017-07-01

    The quality of service (QoS) offered by optical networks can be improved by accurate provisioning of service level specifications (SLSs) included in the service level agreement (SLA). A large number of users coexisting in the network require different services. Thus, a pragmatic network needs to offer a differentiated QoS to a variety of users according to the SLA contracted for different services at varying costs. In conventional wavelength division multiplexed (WDM) optical networks, service differentiation is feasible only for a limited number of users because of its fixed-grid structure. Newly introduced flex-grid based elastic optical networks (EONs) are more adaptive to traffic requirements as compared to the WDM networks because of the flexibility in their grid structure. Thus, we propose an efficient SLA provisioning algorithm with improved QoS for these flex-grid EONs empowered by optical orthogonal frequency division multiplexing (O-OFDM). The proposed algorithm, called SLA-aware differentiated QoS (SADQ), employs differentiation at the level of routing, spectrum allocation, and connection survivability. The proposed SADQ aims to accurately provision the SLA using such multilevel differentiation with an objective to improve the spectrum utilization from the network operator's perspective. SADQ is evaluated for three different CoSs under various traffic demand patterns and for different ratios of the number of requests belonging to the three considered CoSs. We propose two new SLA metrics for the improvement of functional QoS requirements, namely, security, confidentiality and survivability of high class of service (CoS) traffic. Since, to the best of our knowledge, the proposed SADQ is the first scheme in optical networks to employ exhaustive differentiation at the levels of routing, spectrum allocation, and survivability in a single algorithm, we first compare the performance of SADQ in EON and currently deployed WDM networks to assess the

  4. QoS Enabled Resource Allocation Over an UPnP-QoS - GMPLS Controlled Edge

    DEFF Research Database (Denmark)

    Brewka, Lukasz Jerzy; Sköldström, Pontus; Gavler, Anders

    2011-01-01

    This paper focuses on the problem of coherent resource allocation within home and access networks. The interdomain QoS signaling discussed here enables the initiation of the QoS provisioning in the home and access from the end device in users home. The home network considered in this paper is UPn......P-QoS enabled while the access network is GMPLS based. We propose and implement an interface between aforementioned network segments allowing for end-to-end QoS establishment. We present the QoS parameters and mechanisms in both UPnP-QoS and GMPLS and how they can be matched to create a coherent Qo...

  5. Automatic provisioning of end-to-end QoS into the home

    DEFF Research Database (Denmark)

    Brewka, Lukasz Jerzy; Skoldström, Pontus; Nelis, Jelle

    2011-01-01

    Due to a growing number of high bandwidth applications today (such as HDTV), and an increasing amount of network and cloud based applications, service providers need to pay attention to QoS in their networks. We believe there is a need for an end-to-end approach reaching into the home as well....... The Home Gateway (HG) as a key component of the home network is crucial for enabling the end-to-end solutions. UPnP-QoS has been proposed as an inhome solution for resource reservations. In this paper we assess a solution for automatic QoS reservations, on behalf of non-UPnP-QoS aware applications....... Additionally we focus on an integrated end-to-end solution, combining GMPLS-based reservations in e.g., access/metro and UPnP-QoS based reservation in the home network....

  6. Resource management framework for QoS scheduling in IEEE 802.16 WiMAX networks

    DEFF Research Database (Denmark)

    Wang, Hua; Dittmann, Lars

    2009-01-01

    IEEE 802.16, also known as WiMAX, has received much attention recently for its capability to support multiple types of applications with diverse Quality-of-Service (QoS) requirements. Beyond what the standard has defined, radio resource management (RRM) still remains an open issue, which plays...... an important role in QoS provisioning for different types of services. In this chapter, we propose a downlink resource management framework for QoS scheduling in OFDMA based WiMAX systems. Our framework consists of a dynamic resource allocation (DRA) module and a connection admission control (CAC) module...

  7. Downlink resource management for QoS scheduling in IEEE 802.16 WiMAX networks

    DEFF Research Database (Denmark)

    Wang, Hua; Dittmann, Lars

    2010-01-01

    IEEE 802.16, also known as WiMAX, has received much attention recently for its capability to support multiple types of applications with diverse Quality-of-Service (QoS) requirements. Beyond what the standard has defined, radio resource management (RRM) still remains an open issue, which plays...... an important role in QoS provisioning for different types of services. In this paper, we propose a downlink resource management framework for QoS scheduling in OFDMA based WiMAX systems. Our framework consists of a dynamic resource allocation (DRA) module and a connection admission control (CAC) module. A two...

  8. On Designing Thermal-Aware Localized QoS Routing Protocol for in-vivo Sensor Nodes in Wireless Body Area Networks

    OpenAIRE

    Monowar, Muhammad Mostafa; Bajaber, Fuad

    2015-01-01

    In this paper, we address the thermal rise and Quality-of-Service (QoS) provisioning issue for an intra-body Wireless Body Area Network (WBAN) having in-vivo sensor nodes. We propose a thermal-aware QoS routing protocol, called TLQoS, that facilitates the system in achieving desired QoS in terms of delay and reliability for diverse traffic types, as well as avoids the formation of highly heated nodes known as hotspot(s), and keeps the temperature rise along the network to an acceptable level....

  9. Quality of service provision assessment in the healthcare information and telecommunications infrastructures.

    Science.gov (United States)

    Babulak, Eduard

    2006-01-01

    The continuous increase in the complexity and the heterogeneity of corporate and healthcare telecommunications infrastructures will require new assessment methods of quality of service (QoS) provision that are capable of addressing all engineering and social issues with much faster speeds. Speed and accessibility to any information at any time from anywhere will create global communications infrastructures with great performance bottlenecks that may put in danger human lives, power supplies, national economy and security. Regardless of the technology supporting the information flows, the final verdict on the QoS is made by the end user. The users' perception of telecommunications' network infrastructure QoS provision is critical to the successful business management operation of any organization. As a result, it is essential to assess the QoS Provision in the light of user's perception. This article presents a cost effective methodology to assess the user's perception of quality of service provision utilizing the existing Staffordshire University Network (SUN) by adding a component of measurement to the existing model presented by Walker. This paper presents the real examples of CISCO Networking Solutions for Health Care givers and offers a cost effective approach to assess the QoS provision within the campus network, which could be easily adapted to any health care organization or campus network in the world.

  10. Context-aware QoS provisioning for an M-health service platform

    OpenAIRE

    Wac, K.E.; Delgado Kloos, C.; Larrabeiti, D.; van Halteren, Aart; Bults, Richard G.A.; Lopez, A.M.; Broens, T.H.F.

    2007-01-01

    Inevitably, healthcare goes mobile. Recently developed mobile healthcare (i.e., m-health) services allow healthcare professionals to monitor mobile patient’s vital signs and provide feedback to this patient anywhere at any time. Due to the nature of current supporting mobile service platforms, m-health services are delivered with a best-effort, i.e., there are no guarantees on the delivered Quality of Service (QoS). In this paper, we argue that the use of context information in an m-health se...

  11. Anticipation of Traffic Demands to Guarantee QoS in IP/Optical Networks

    Directory of Open Access Journals (Sweden)

    Carolina Pinart

    2010-09-01

    Full Text Available Traffic in the Internet backbone is expected to grow above a few Tbit/s in 2020. To cope with this, operators are moving to IP/optical network architectures, where IP is the convergence layer for all services. On the other hand, the quality of service (QoS requirements of future applications encompasses the individualization of services and the assurance of stricter quality parameters such as latency, jitter or capacity. In other words, future optical networks will not only transport more IP data, but they will also have to offer differentiated QoS requirements to services. Finally, some emerging applications, e.g., grid computing, need greater flexibility in the usage of network resources, which involves establishing and releasing connections as if they were virtualized resources controlled by other elements or layers. In this context, traffic-driven lightpath provisioning and service-plane approaches arise as very interesting candidate solutions to solve the main challenges described above. This work reviews the concepts of service-oriented and self-managed networks and relates them to propose an integrated approach to assure QoS by offering flow-aware networking in the sense that traffic demands will be anticipated in a suitable way, lightpaths will be established taking into account QoS information (i.e., impairments and complex services will be decomposed into optical connections so that the above techniques can be employed to assure QoS for any service.

  12. Differential private collaborative Web services QoS prediction

    KAUST Repository

    Liu, An

    2018-04-04

    Collaborative Web services QoS prediction has proved to be an important tool to estimate accurately personalized QoS experienced by individual users, which is beneficial for a variety of operations in the service ecosystem, such as service selection, composition and recommendation. While a number of achievements have been attained on the study of improving the accuracy of collaborative QoS prediction, little work has been done for protecting user privacy in this process. In this paper, we propose a privacy-preserving collaborative QoS prediction framework which can protect the private data of users while retaining the ability of generating accurate QoS prediction. We introduce differential privacy, a rigorous and provable privacy model, into the process of collaborative QoS prediction. We first present DPS, a method that disguises a user’s observed QoS values by applying differential privacy to the user’s QoS data directly. We show how to integrate DPS with two representative collaborative QoS prediction approaches. To improve the utility of the disguised QoS data, we present DPA, another QoS disguising method which first aggregates a user’s QoS data before adding noise to achieve differential privacy. We evaluate the proposed methods by conducting extensive experiments on a real world Web services QoS dataset. Experimental results show our approach is feasible in practice.

  13. Differential private collaborative Web services QoS prediction

    KAUST Repository

    Liu, An; Shen, Xindi; Li, Zhixu; Liu, Guanfeng; Xu, Jiajie; Zhao, Lei; Zheng, Kai; Shang, Shuo

    2018-01-01

    Collaborative Web services QoS prediction has proved to be an important tool to estimate accurately personalized QoS experienced by individual users, which is beneficial for a variety of operations in the service ecosystem, such as service selection, composition and recommendation. While a number of achievements have been attained on the study of improving the accuracy of collaborative QoS prediction, little work has been done for protecting user privacy in this process. In this paper, we propose a privacy-preserving collaborative QoS prediction framework which can protect the private data of users while retaining the ability of generating accurate QoS prediction. We introduce differential privacy, a rigorous and provable privacy model, into the process of collaborative QoS prediction. We first present DPS, a method that disguises a user’s observed QoS values by applying differential privacy to the user’s QoS data directly. We show how to integrate DPS with two representative collaborative QoS prediction approaches. To improve the utility of the disguised QoS data, we present DPA, another QoS disguising method which first aggregates a user’s QoS data before adding noise to achieve differential privacy. We evaluate the proposed methods by conducting extensive experiments on a real world Web services QoS dataset. Experimental results show our approach is feasible in practice.

  14. QoS management of web services

    CERN Document Server

    Zheng, Zibin

    2013-01-01

    Quality-of-Service (QoS) is normally used to describe the non-functional characteristics of Web services and as a criterion for evaluating different Web services. QoS Management of Web Services presents an innovative QoS evaluation framework for these services. Moreover, three QoS prediction methods and two methods for creating fault-tolerant Web services are also proposed in this book. It not only provides the latest research findings, but also presents an excellent overview of the QoS management of Web services, making it a valuable resource for researchers and graduate students in service computing.   Zibin Zheng is an associate research fellow at the Shenzhen Research Institute, the Chinese University of Hong Kong, China. Professor Michael R. Lyu also works at the same institute.

  15. OPTIMISATION OF BUFFER SIZE FOR ENHANCING QOS OF VIDEO TRAFFIC USING CROSS LAYERED HYBRID TRANSPORT LAYER PROTOCOL APPROACH

    Directory of Open Access Journals (Sweden)

    S. Matilda

    2011-03-01

    Full Text Available Video streaming is gaining importance, with the wide popularity of multimedia rich applications in the Internet. Video streams are delay sensitive and require seamless flow for continuous visualization. Properly designed buffers offer a solution to queuing delay. The diagonally opposite QoS metrics associated with video traffic poses an optimization problem, in the design of buffers. This paper is a continuation of our previous work [1] and deals with the design of buffers. It aims at finding the optimum buffer size for enhancing QoS offered to video traffic. Network-centric QoS provisioning approach, along with hybrid transport layer protocol approach is adopted, to arrive at an optimum size which is independent of RTT. In this combinational approach, buffers of routers and end devices are designed to satisfy the various QoS parameters at the transport layer. OPNET Modeler is used to simulate environments for testing the design. Based on the results of simulation it is evident that the hybrid transport layer protocol approach is best suited for transmitting video traffic as it supports the economical design.

  16. Thermal-Aware Multiconstrained Intrabody QoS Routing for Wireless Body Area Networks

    OpenAIRE

    Muhammad Mostafa Monowar; Mohammad Mehedi Hassan; Fuad Bajaber; Md. Abdul Hamid; Atif Alamri

    2014-01-01

    Wireless body area networks (WBANs) can be formed including implanted biosensors for health monitoring and diagnostic purposes. However, implanted biosensors could cause thermal damages on human tissue as it exhibits temperature rise due to wireless communication and processing tasks inside the human body. Again, Quality of Service (QoS) provisioning with multiconstraints (delay and reliability) is a striking requirement for diverse application types in WBANs to meet their objectives. This pa...

  17. A game theoretical approach for QoS provisioning in heterogeneous networks

    Directory of Open Access Journals (Sweden)

    A.S.M. Zadid Shifat

    2015-09-01

    Full Text Available With the proliferation of mobile phone users, interference management is a big concern in this neoteric years. To cope with this problem along with ensuring better Quality of Service (QoS, femtocell plays an imperious preamble in heterogeneous networks (HetNets for some of its noteworthy characteristics. In this paper, we propose a game theoretic algorithm along with dynamic channel allocation and hybrid access mechanism with self-organizing power control scheme. With a view to resolving prioritized access issue, the concept of primary and secondary users is applied. Existence of pure strategy Nash equilibrium (NE has been investigated and comes to a perfection that our proposed scheme can be adopted both increasing capacity and increasing revenue of operators considering optimal price for consumers.

  18. On Designing Thermal-Aware Localized QoS Routing Protocol for in-vivo Sensor Nodes in Wireless Body Area Networks.

    Science.gov (United States)

    Monowar, Muhammad Mostafa; Bajaber, Fuad

    2015-06-15

    In this paper, we address the thermal rise and Quality-of-Service (QoS) provisioning issue for an intra-body Wireless Body Area Network (WBAN) having in-vivo sensor nodes. We propose a thermal-aware QoS routing protocol, called TLQoS, that facilitates the system in achieving desired QoS in terms of delay and reliability for diverse traffic types, as well as avoids the formation of highly heated nodes known as hotspot(s), and keeps the temperature rise along the network to an acceptable level. TLQoS exploits modular architecture wherein different modules perform integrated operations in providing multiple QoS service with lower temperature rise. To address the challenges of highly dynamic wireless environment inside the human body. TLQoS implements potential-based localized routing that requires only local neighborhood information. TLQoS avoids routing loop formation as well as reduces the number of hop traversal exploiting hybrid potential, and tuning a configurable parameter. We perform extensive simulations of TLQoS, and the results show that TLQoS has significant performance improvements over state-of-the-art approaches.

  19. A Network-Attached Storage System Supporting Guaranteed QoS

    Institute of Scientific and Technical Information of China (English)

    KONG Hua-feng; YU Sheng-sheng; LU Hong-wei

    2005-01-01

    We propose a network-attached storage system that can support guaranteed Quality of Service (QoS), called POPNet Storage. The special policy of date access and disk scheduling is enable users to access files quickly and directly with guaranteed QoS in the POPNet Storage. The POPNet Storage implements a measurement-based admission control algorithm (PSMBAC) to determine whether to admit a new data access request stream and admit as many requests as possible while meeting the QoS guarantees to its clients. The data reconstruction algorithms in the POPNet Storage also put more emphasis on data availability and guaranteed QoS, thus it is designed to complete the data recovery as soon as possible and at the same time provide the guaranteed QoS for high-priority data access. The experiment results show that the POPNet Storage can provide more significant performance, reliability, and guaranteed QoS than conventional storage systems.

  20. On Designing Thermal-Aware Localized QoS Routing Protocol for in-vivo Sensor Nodes in Wireless Body Area Networks

    Directory of Open Access Journals (Sweden)

    Muhammad Mostafa Monowar

    2015-06-01

    Full Text Available In this paper, we address the thermal rise and Quality-of-Service (QoS provisioning issue for an intra-body Wireless Body Area Network (WBAN having in-vivo sensor nodes. We propose a thermal-aware QoS routing protocol, called TLQoS, that facilitates the system in achieving desired QoS in terms of delay and reliability for diverse traffic types, as well as avoids the formation of highly heated nodes known as hotspot(s, and keeps the temperature rise along the network to an acceptable level. TLQoS exploits modular architecture wherein different modules perform integrated operations in providing multiple QoS service with lower temperature rise. To address the challenges of highly dynamic wireless environment inside the human body. TLQoS implements potential-based localized routing that requires only local neighborhood information. TLQoS avoids routing loop formation as well as reduces the number of hop traversal exploiting hybrid potential, and tuning a configurable parameter. We perform extensive simulations of TLQoS, and the results show that TLQoS has significant performance improvements over state-of-the-art approaches.

  1. Providing QoS guarantee in 3G wireless networks

    Science.gov (United States)

    Chuah, MooiChoo; Huang, Min; Kumar, Suresh

    2001-07-01

    The third generation networks and services present opportunities to offer multimedia applications and services that meet end-to-end quality of service requirements. In this article, we present UMTS QoS architecture and its requirements. This includes the definition of QoS parameters, traffic classes, the end-to-end data delivery model, and the mapping of end-to-end services to the services provided by the network elements of the UMTS. End-to-end QoS of a user flow is achieved by the combination of the QoS control over UMTS Domain and the IP core Network. In the Third Generation Wireless network, UMTS bearer service manager is responsible to manage radio and transport resources to QoS-enabled applications. The UMTS bearer service consists of the Radio Access Bearer Service between Mobile Terminal and SGSN and Core Network bearer service between SGSN and GGSN. The Radio Access Bearer Service is further realized by the Radio Bearer Service (mostly air interface) and Iu bearer service. For the 3G air interface, one can provide differentiated QoS via intelligent burst allocation scheme, adaptive spreading factor control and weighted fair queueing scheduling algorithms. Next, we discuss the requirements for the transport technologies in the radio access network to provide differentiated QoS to multiple classes of traffic. We discuss both ATM based and IP based transport solutions. Last but not least, we discuss how QoS mechanism is provided in the core network to ensure e2e quality of service requirements. We discuss how mobile terminals that use RSVP as QoS signaling mechanisms can be are supported in the 3G network which may implement only IETF diffserv mechanism. . We discuss how one can map UMTS QoS classes with IETF diffserv code points. We also discuss 2G/3G handover scenarios and how the 2G/3G QoS parameters can be mapped.

  2. Evaluation of QoS supported in Network Mobility NEMO environments

    International Nuclear Information System (INIS)

    Hussien, L F; Abdalla, A H; Habaebi, M H; Khalifa, O O; Hassan, W H

    2013-01-01

    Network mobility basic support (NEMO BS) protocol is an entire network, roaming as a unit which changes its point of attachment to the Internet and consequently its reachability in the network topology. NEMO BS doesn't provide QoS guarantees to its users same as traditional Internet IP and Mobile IPv6 as well. Typically, all the users will have same level of services without considering about their application requirements. This poses a problem to real-time applications that required QoS guarantees. To gain more effective control of the network, incorporated QoS is needed. Within QoS-enabled network the traffic flow can be distributed to various priorities. Also, the network bandwidth and resources can be allocated to different applications and users. Internet Engineering Task Force (IETF) working group has proposed several QoS solutions for static network such as IntServ, DiffServ and MPLS. These QoS solutions are designed in the context of a static environment (i.e. fixed hosts and networks). However, they are not fully adapted to mobile environments. They essentially demands to be extended and adjusted to meet up various challenges involved in mobile environments. With existing QoS mechanisms many proposals have been developed to provide QoS for individual mobile nodes (i.e. host mobility). In contrary, research based on the movement of the whole mobile network in IPv6 is still undertaking by the IETF working groups (i.e. network mobility). Few researches have been done in the area of providing QoS for roaming networks. Therefore, this paper aims to review and investigate (previous /and current) related works that have been developed to provide QoS in mobile network. Consequently, a new proposed scheme will be introduced to enhance QoS within NEMO environment, achieving by which seamless mobility to users of mobile network node (MNN)

  3. QoS and QoE Aware N-Screen Multicast Service

    Directory of Open Access Journals (Sweden)

    Ghulam Sarwar

    2016-01-01

    Full Text Available The paper focuses on ensuring the quality-of-service (QoS and quality-of-experience (QoE requirements of users having heterogeneous devices in a multicast session. QoS parameters such as bit rate, delays, and packet losses are good indicators for optimizing network services but fall short in characterizing user perception (QoE. In N-Screen service, the users have different devices with heterogeneous attributes like screen size, resolution, and access network interface, and the users have different QoE on N-Screen devices with the same QoS parameters. We formulate the objective function of the N-Screen multicast grouping to ensure the minimum user’s QoE with smaller bandwidth requirement. We propose a dynamic user reassignment scheme to maintain and satisfy the QoE by adapting the user’s membership to the varying network conditions. The proposed schemes combine the available bandwidth and multimedia visual quality to ensure the QoS and QoE. In the network architecture, we introduce the functions of the QoS and QoE aware multicast group management and the estimation schemes for the QoS and QoE parameters. The simulation results show that the proposed multicast service ensures the network QoS and guarantees the QoE of users in the varying network conditions.

  4. A QoS aware services mashup model for cloud computing applications

    Directory of Open Access Journals (Sweden)

    Yee Ming Chen

    2012-12-01

    Full Text Available Purpose: With the popularity of cloud computing, cloud services have become to be application programming platform where users can create new applications mashup(composing the functionality offered byothers.By composing of distributed, cloud services dynamicallyto provide more complex tasks, services mashup provides an attractive way for building large-scale Internetapplications.Oneof the challenging issues of cloud services mashup is how to find service paths to route the service instances provider through whilemeeting the applications’ resource requirements so that the QoS constraints are satisfied. However, QoS aware service routing problem istypically NP-hard.The purpose of this paper is to propose a QoS Aware Services Mashup(QASM model to solve this problem more effectively.Design/methodology/approach: In this paper, we focus on the QoS aware services selection problem in cloud services mashup, for example, given the user service composition requirements and their QoS constraint descriptions, how to select the required serviceinstances and route the data flows through these instances so that the QoS requirements are satisfied. We design a heuristic algorithm to find service paths to route the data flows through whilemeeting the applications’ resource requirements and specific QoS constraints.Findings: This study propose a QoS Aware Services Mashup(QASM model to solve this problem more effectively. Simulations show that QASM can achieve desired QoS assurances as well as load balancing in cloud services environment.Originality/value: This paperpresent a QASM model for providing high performance distributedapplications in the cloud computing systems.

  5. TD-LTE Wireless Private Network QoS Transmission Protection

    Science.gov (United States)

    Zhang, Jianming; Cheng, Chao; Wu, Zanhong

    With the commencement of construction of the smart grid, the demand power business for reliability and security continues to improve, the reliability transmission of power TD-LTE Wireless Private Network are more and more attention. For TD-LTE power private network, it can provide different QoS services according to the user's business type, to protect the reliable transmission of business. This article describes in detail the AF module of PCC in the EPC network, specifically introduces set up AF module station and QoS mechanisms in the EPS load, fully considers the business characteristics of the special power network, establishing a suitable architecture for mapping QoS parameters, ensuring the implementation of each QoS business. Through using radio bearer management, we can achieve the reliable transmission of each business on physical channel.

  6. QoS Predictability of Internet Services

    Science.gov (United States)

    Bilski, Tomasz

    The paper presents problems of QoS (Quality of Service) predictability of network services (mainly in WAN environment). In the first part we present general remarks on QoS predictability problem, mentioning some research projects and available resources. The main part of the paper deals with QoS predictability in long-term as well as short-term viewpoints. We will try to answer a question: is it possible to predict network QoS/performance level with a use of statistical data from the past? The term quality of service has many meanings ranging from the user's qualitative perception of the service to a set of quantitative connection parameters (RTT (Round Trip Time), throughput, loss packet rate) necessary to achieve particular service quality. In the paper we will mostly use the second meaning of the term based on RFC 2386 [1]. Analyzed, statistical data on Internet performance are taken from the IEPM (Internet End-to-end Performance Measurement) database.

  7. Network based control point for UPnP QoS architecture

    DEFF Research Database (Denmark)

    Brewka, Lukasz Jerzy; Wessing, Henrik; Rossello Busquet, Ana

    2011-01-01

    Enabling coexistence of non-UPnP Devices in an UPnP QoS Architecture is an important issue that might have a major impact on the deployment and usability of UPnP in future home networks. The work presented here shows potential issues of placing non-UPnP Device in the network managed by UPnP QoS. We...... address this issue by extensions to the UPnP QoS Architecture that can prevent non-UPnP Devices from degrading the overall QoS level. The obtained results show that deploying Network Based Control Point service with efficient traffic classifier, improves significantly the end-to-end packet delay...

  8. QoS Negotiation and Renegotiation Based on Mobile Agents

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shi-bing; ZHANG Deng-yin

    2006-01-01

    The Quality of Service (QoS) has received more and more attention since QoS becomes increasingly important in the Internet development. Mobile software agents represent a valid alternative to the implementation of strategies for the negotiation. In this paper, a QoS negotiation and renegotiation system architecture based on mobile agents is proposed. The agents perform the task in the whole process. Therefore, such a system can reduce the network load, overcome latency, and avoid frequent exchange information between clients and server. The simulation results show that the proposed system could improve the network resource utility about 10%.

  9. An Intelligent QoS Identification for Untrustworthy Web Services Via Two-phase Neural Networks

    OpenAIRE

    Wang, Weidong; Wang, Liqiang; Lu, Wei

    2016-01-01

    QoS identification for untrustworthy Web services is critical in QoS management in the service computing since the performance of untrustworthy Web services may result in QoS downgrade. The key issue is to intelligently learn the characteristics of trustworthy Web services from different QoS levels, then to identify the untrustworthy ones according to the characteristics of QoS metrics. As one of the intelligent identification approaches, deep neural network has emerged as a powerful techniqu...

  10. IP access networks with QoS support

    Science.gov (United States)

    Sargento, Susana; Valadas, Rui J. M. T.; Goncalves, Jorge; Sousa, Henrique

    2001-07-01

    The increasing demand of new services and applications is pushing for drastic changes on the design of access networks targeted mainly for residential and SOHO users. Future access networks will provide full service integration (including multimedia), resource sharing at the packet level and QoS support. It is expected that using IP as the base technology, the ideal plug-and-play scenario, where the management actions of the access network operator are kept to a minimum, will be achieved easily. This paper proposes an architecture for access networks based on layer 2 or layer 3 multiplexers that allows a number of simplifications in the network elements and protocols (e.g. in the routing and addressing functions). We discuss two possible steps in the evolution of access networks towards a more efficient support of IP based services. The first one still provides no QoS support and was designed with the goal of reusing as much as possible current technologies; it is based on tunneling to transport PPP sessions. The second one introduces QoS support through the use of emerging technologies and protocols. We illustrate the different phases of a multimedia Internet access session, when using SIP for session initiation, COPS for the management of QoS policies including the AAA functions and RSVP for resource reservation.

  11. RACOON: a multiuser QoS design for mobile wireless body area networks.

    Science.gov (United States)

    Cheng, Shihheng; Huang, Chingyao; Tu, Chun Chen

    2011-10-01

    In this study, Random Contention-based Resource Allocation (RACOON) medium access control (MAC) protocol is proposed to support the quality of service (QoS) for multi-user mobile wireless body area networks (WBANs). Different from existing QoS designs that focus on a single WBAN, a multiuser WBAN QoS should further consider both inter-WBAN interference and inter-WBAN priorities. Similar problems have been studied in both overlapped wireless local area networks (WLANs) and Bluetooth piconets that need QoS supports. However, these solutions are designed for non-medical transmissions that do not consider any priority scheme for medical applications. Most importantly, these studies focus on only static or low mobility networks. Network mobility of WBANs will introduce unnecessary inter-network collisions and energy waste, which are not considered by these solutions. The proposed multiuser-QoS protocol, RACOON, simultaneously satisfies the inter WBAN QoS requirements and overcomes the performance degradation caused by WBAN mobility. Simulation results verify that RACOON provides better latency and energy control, as compared with WBAN QoS protocols without considering the inter-WBAN requirements.

  12. Optimal Network QoS over the Internet of Vehicles for E-Health Applications

    Directory of Open Access Journals (Sweden)

    Di Lin

    2016-01-01

    Full Text Available Wireless technologies are pervasive to support ubiquitous healthcare applications. However, a critical issue of using wireless communications under a healthcare scenario is the electromagnetic interference (EMI caused by RF transmission, and a high level of EMI may lead to a critical malfunction of medical sensors. In consideration of EMI on medical sensors, we study the optimization of quality of service (QoS within the whole Internet of vehicles for E-health and propose a novel model to optimize the QoS by allocating the transmit power of each user. Our results show that the optimal power control policy depends on the objective of optimization problems: a greedy policy is optimal to maximize the summation of QoS of each user, whereas a fair policy is optimal to maximize the product of QoS of each user. Algorithms are taken to derive the optimal policies, and numerical results of optimizing QoS are presented for both objectives and QoS constraints.

  13. Analyzing Comprehensive QoS with Security Constraints for Services Composition Applications in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Naixue Xiong

    2014-12-01

    Full Text Available Services composition is fundamental to software development in multi-service wireless sensor networks (WSNs. The quality of service (QoS of services composition applications (SCAs are confronted with severe challenges due to the open, dynamic, and complex natures of WSNs. Most previous research separated various QoS indices into different fields and studied them individually due to the computational complexity. This approach ignores the mutual influence between these QoS indices, and leads to a non-comprehensive and inaccurate analysis result. The universal generating function (UGF shows the speediness and precision in QoS analysis. However, only one QoS index at a time can be analyzed by the classic UGF. In order to efficiently analyze the comprehensive QoS of SCAs, this paper proposes an improved UGF technique—vector universal generating function (VUGF—which considers the relationship between multiple QoS indices, including security, and can simultaneously analyze multiple QoS indices. The numerical examples demonstrate that it can be used for the evaluation of the comprehensive QoS of SCAs subjected to the security constraint in WSNs. Therefore, it can be effectively applied to the optimal design of multi-service WSNs.

  14. Analyzing comprehensive QoS with security constraints for services composition applications in wireless sensor networks.

    Science.gov (United States)

    Xiong, Naixue; Wu, Zhao; Huang, Yannong; Xu, Degang

    2014-12-01

    Services composition is fundamental to software development in multi-service wireless sensor networks (WSNs). The quality of service (QoS) of services composition applications (SCAs) are confronted with severe challenges due to the open, dynamic, and complex natures of WSNs. Most previous research separated various QoS indices into different fields and studied them individually due to the computational complexity. This approach ignores the mutual influence between these QoS indices, and leads to a non-comprehensive and inaccurate analysis result. The universal generating function (UGF) shows the speediness and precision in QoS analysis. However, only one QoS index at a time can be analyzed by the classic UGF. In order to efficiently analyze the comprehensive QoS of SCAs, this paper proposes an improved UGF technique-vector universal generating function (VUGF)-which considers the relationship between multiple QoS indices, including security, and can simultaneously analyze multiple QoS indices. The numerical examples demonstrate that it can be used for the evaluation of the comprehensive QoS of SCAs subjected to the security constraint in WSNs. Therefore, it can be effectively applied to the optimal design of multi-service WSNs.

  15. APIs for QoS configuration in Software Defined Networks

    DEFF Research Database (Denmark)

    Caba, Cosmin Marius; Soler, José

    2015-01-01

    The OpenFlow (OF) protocol is widely used in Software Defined Networking (SDN) to realize the communication between the controller and forwarding devices. OF allows great flexibility in managing traffic flows. However, OF alone is not enough to build more complex SDN services that require complete...... such as configuration of devices, ports, queues, etc. An Application Programming Interface (API) for dynamic configuration of QoS resources in the network devices is implemented herein, by using the capabilities of OVSDB. Further, the paper demonstrates the possibility to create network services with coarse granularity...... on top of the fine granular services exposed by the QoS configuration API at the SDNC. A series of tests emphasize the capabilities and the performance of the implemented QoS configuration API....

  16. Device Centric Throughput and QoS Optimization for IoTsin a Smart Building Using CRN-Techniques

    Directory of Open Access Journals (Sweden)

    Saleem Aslam

    2016-10-01

    Full Text Available The Internet of Things (IoT has gained an incredible importance in the communication and networking industry due to its innovative solutions and advantages in diverse domains. The IoT’ network is a network of smart physical objects: devices, vehicles, buildings, etc. The IoT has a number of applications ranging from smart home, smart surveillance to smart healthcare systems. Since IoT consists of various heterogeneous devices that exhibit different traffic patterns and expect different quality of service (QoS in terms of data rate, bit error rate and the stability index of the channel, therefore, in this paper, we formulated an optimization problem to assign channels to heterogeneous IoT devices within a smart building for the provisioning of their desired QoS. To solve this problem, a novel particle swarm optimization-based algorithm is proposed. Then, exhaustive simulations are carried out to evaluate the performance of the proposed algorithm. Simulation results demonstrate the supremacy of our proposed algorithm over the existing ones in terms of throughput, bit error rate and the stability index of the channel.

  17. A QoS Scheme for a Congestion Core Network Based on Dissimilar QoS Structures in Smart-Phone Environments

    Science.gov (United States)

    Hong, Sung-Ryong; Na, Wonshik; Kang, Jang-Mook

    2010-01-01

    This study suggests an approach to effective transmission of multimedia content in a rapidly changing Internet environment including smart-phones. Guaranteeing QoS in networks is currently an important research topic. When transmitting Assured Forwarding (AF) packets in a Multi-DiffServ network environment, network A may assign priority in an order AF1, AF2, AF3 and AF4; on the other hand, network B may reverse the order to a priority AF4, AF3, AF2 and AF1. In this case, the AF1 packets that received the best quality of service in network A will receive the lowest in network B, which may result in dropping of packets in network B and vice versa. This study suggests a way to guarantee QoS between hosts by minimizing the loss of AF packet class when one network transmits AF class packets to another network with differing principles. It is expected that QoS guarantees and their experimental value may be utilized as principles which can be applied to various mobile-web environments based on smart-phones. PMID:22163453

  18. CCSDS Advanced Orbiting Systems Virtual Channel Access Service for QoS MACHETE Model

    Science.gov (United States)

    Jennings, Esther H.; Segui, John S.

    2011-01-01

    To support various communications requirements imposed by different missions, interplanetary communication protocols need to be designed, validated, and evaluated carefully. Multimission Advanced Communications Hybrid Environment for Test and Evaluation (MACHETE), described in "Simulator of Space Communication Networks" (NPO-41373), NASA Tech Briefs, Vol. 29, No. 8 (August 2005), p. 44, combines various tools for simulation and performance analysis of space networks. The MACHETE environment supports orbital analysis, link budget analysis, communications network simulations, and hardware-in-the-loop testing. By building abstract behavioral models of network protocols, one can validate performance after identifying the appropriate metrics of interest. The innovators have extended the MACHETE model library to include a generic link-layer Virtual Channel (VC) model supporting quality-of-service (QoS) controls based on IP streams. The main purpose of this generic Virtual Channel model addition was to interface fine-grain flow-based QoS (quality of service) between the network and MAC layers of the QualNet simulator, a commercial component of MACHETE. This software model adds the capability of mapping IP streams, based on header fields, to virtual channel numbers, allowing extended QoS handling at link layer. This feature further refines the QoS v existing at the network layer. QoS at the network layer (e.g. diffserv) supports few QoS classes, so data from one class will be aggregated together; differentiating between flows internal to a class/priority is not supported. By adding QoS classification capability between network and MAC layers through VC, one maps multiple VCs onto the same physical link. Users then specify different VC weights, and different queuing and scheduling policies at the link layer. This VC model supports system performance analysis of various virtual channel link-layer QoS queuing schemes independent of the network-layer QoS systems.

  19. Uplink Cross-Layer Scheduling with Differential QoS Requirements in OFDMA Systems

    Directory of Open Access Journals (Sweden)

    Chen Wei

    2010-01-01

    Full Text Available Fair and efficient scheduling is a key issue in cross-layer design for wireless communication systems, such as 3GPP LTE and WiMAX. However, few works have considered the multiaccess of the traffic with differential QoS requirements in wireless systems. In this paper, we will consider an OFDMA-based wireless system with four types of traffic associated with differential QoS requirements, namely, minimum reserved rate, maximum sustainable rate, maximum latency, and tolerant jitter. Given these QoS requirements, the traffic scheduling will be formulated into a cross-layer optimization problem, which is convex fortunately. By separating the power allocation through the waterfilling algorithm in each user, this problem will further reduce to a kind of continuous quadratic knapsack problem in the base station which yields low complexity. It is then demonstrated that the proposed cross-layer method cannot only guarantee the application layer QoS requirements, but also minimizes the integrated residual workload in the MAC layer. To further enhance the ability of QoS assurance in heavily loaded scenario, a call admission control scheme will also be proposed. The simulation results show that the QoS requirements for the four types of traffic are guaranteed effectively by the proposed algorithms.

  20. Autonomous QoS Management and Policing in Unmanaged Local Area Networks

    Directory of Open Access Journals (Sweden)

    Christopher Köhnen

    2015-01-01

    Full Text Available The high increase of bandwidth-intensive applications like high definition video streaming in home and small office environments leads to QoS challenges in hybrid wired/wireless local area networks. These networks are often not QoS aware and may contain bottlenecks in their topology. In addition, they often have a hybrid nature due to the used access technology consisting of, for example, Ethernet, wireless, and PowerLAN links. In this paper, we present the research work on a novel autonomous system for hybrid QoS in local area networks, called QoSiLAN, which does not rely on network infrastructure support but on host cooperation and works independently of the access technology. We present a new QoS Signalling Protocol, policing and admission control algorithms, and a new lightweight statistical bandwidth prediction algorithm for autonomous resource management in LANs. This new QoS framework enables link based, access-medium independent bandwidth management without network support. We provide evaluation results for the novel bandwidth prediction algorithm as well as for the QoSiLAN framework and its protocol, which highlight the features, robustness, and the effectiveness of the proposed system.

  1. Using Kalman Filter to Guarantee QoS Robustness of Web Server

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The exponential growth of the Internet coupled with the increasing popularity of dynamically generated content on the World Wide Web, has created the need for more and faster Web servers capable of serving the over 100 million Internet users. To converge the control method has emerged as a promising technique to solve the Web QoS problem. In this paper, a model of adaptive session is presented and a session flow self-regulating algorism based on Kalman Filter are proposed towards Web Server. And a Web QoS self-regulating scheme is advanced. To attain the goal of on-line system identification, the optimized estimation of QoS parameters is fulfilled by utilizing Kalman Filter in full domain. The simulation results shows that the proposed scheme can guarantee the QoS with both robustness and stability .

  2. BP Network Control for Resource Allocation and QoS Ensurance in UAV Cloud

    Directory of Open Access Journals (Sweden)

    Ang Gao

    2018-01-01

    Full Text Available Unmanned aerial vehicle (UAV cloud can greatly enhance the intelligence of unmanned systems by dynamically unloading the compute-intensive applications to cloud. For the uncertain nature of UAV missions and fast-changing environment, different UAV applications may have different quality of service (QoS requirements. This paper proposes a mixed QoS ensurance and energy-balanced (MQEB architecture for UAV cloud from a view of control theory, which can support both hard and soft QoS ensurance with the consideration of energy saving. The hard and soft QoS requirements are decoupled by being normalized into a two-level cascaded feedback loop. The former is time slot loop (TS-Loop to enforce the absolute QoS ensurance for real-time applications, and the latter is contention window loop (CW-Loop to enforce the plastic QoS ensurance for non-real-time applications. Finally, the back propagating (BP neuron network is used for parameters’ self-tuning and controller design. The hardware experiments demonstrate the feasibility of MQEB. In heavy load, MQEB has greater throughput and better energy efficiency, and in light load, MQBE has lower total power consumption.

  3. A QoS Framework with Traffic Request in Wireless Mesh Network

    Science.gov (United States)

    Fu, Bo; Huang, Hejiao

    In this paper, we consider major issues in ensuring greater Quality-of-Service (QoS) in Wireless Mesh Networks (WMNs), specifically with regard to reliability and delay. To this end, we use traffic request to record QoS requirements of data flows. In order to achieve required QoS for all data flows efficiently and with high portability, we develop Network State Update Algorithm. All assumptions, definitions, and algorithms are made exclusively with WMNs in mind, guaranteeing the portability of our framework to various environments in WMNs. The simulation results in proof that our framework is correct.

  4. PERFORMANCE ANALYSIS OF AI BASED QOS SCHEDULER FOR MOBILE WIMAX

    Directory of Open Access Journals (Sweden)

    D. David Neels Pon Kumar

    2012-09-01

    Full Text Available Interest in broadband wireless access (BWA has been growing due to increased user mobility and the need for data access at all times. IEEE 802.16e based WiMAX networks promise the best available quality of experience for mobile data service users. WiMAX networks incorporate several Quality of Service (QoS mechanisms at the Media Access Control (MAC level for guaranteed services for multimedia viz. data, voice and video. The problem of assuring QoS is how to allocate available resources among users to meet the QoS criteria such as delay, delay jitter, fairness and throughput requirements. IEEE standard does not include a standard scheduling mechanism and leaves it for various implementer differentiations. Although a lot of the real-time and non real-time packet scheduling schemes has been proposed, it needs to be modified to apply to Mobile WiMAX system that supports five kinds of service classes. In this paper, we propose a novel Priority based Scheduling scheme that uses Artificial Intelligence to support various services by considering the QoS constraints of each class. The simulation results show that slow mobility does not affect the performances and faster mobility and the increment in users beyond a particular load have their say in defining average throughput, average per user throughput, fairness index, average end to end delay and average delay jitter. Nevertheless the results are encouraging that the proposed scheme provides QoS support for each class efficiently.

  5. QOS-aware error recovery in wireless body sensor networks using adaptive network coding.

    Science.gov (United States)

    Razzaque, Mohammad Abdur; Javadi, Saeideh S; Coulibaly, Yahaya; Hira, Muta Tah

    2014-12-29

    Wireless body sensor networks (WBSNs) for healthcare and medical applications are real-time and life-critical infrastructures, which require a strict guarantee of quality of service (QoS), in terms of latency, error rate and reliability. Considering the criticality of healthcare and medical applications, WBSNs need to fulfill users/applications and the corresponding network's QoS requirements. For instance, for a real-time application to support on-time data delivery, a WBSN needs to guarantee a constrained delay at the network level. A network coding-based error recovery mechanism is an emerging mechanism that can be used in these systems to support QoS at very low energy, memory and hardware cost. However, in dynamic network environments and user requirements, the original non-adaptive version of network coding fails to support some of the network and user QoS requirements. This work explores the QoS requirements of WBSNs in both perspectives of QoS. Based on these requirements, this paper proposes an adaptive network coding-based, QoS-aware error recovery mechanism for WBSNs. It utilizes network-level and user-/application-level information to make it adaptive in both contexts. Thus, it provides improved QoS support adaptively in terms of reliability, energy efficiency and delay. Simulation results show the potential of the proposed mechanism in terms of adaptability, reliability, real-time data delivery and network lifetime compared to its counterparts.

  6. An Application-Level QoS Control Method Based on Local Bandwidth Scheduling

    Directory of Open Access Journals (Sweden)

    Yong Wang

    2018-01-01

    Full Text Available Quality of service (QoS is an important performance indicator for Web applications and bandwidth is a key factor affecting QoS. Current methods use network protocols or ports to schedule bandwidth, which require tedious manual configurations or modifications of the underlying network. Some applications use dynamic ports and the traditional port-based bandwidth control methods cannot deal with them. A new QoS control method based on local bandwidth scheduling is proposed, which can schedule bandwidth at application level in a user-transparent way and it does not require tedious manual configurations. Experimental results indicate that the new method can effectively improve the QoS for applications, and it can be easily integrated into current Web applications without the need to modify the underlying network.

  7. Real-Time QoS Routing Protocols in Wireless Multimedia Sensor Networks: Study and Analysis.

    Science.gov (United States)

    Alanazi, Adwan; Elleithy, Khaled

    2015-09-02

    Many routing protocols have been proposed for wireless sensor networks. These routing protocols are almost always based on energy efficiency. However, recent advances in complementary metal-oxide semiconductor (CMOS) cameras and small microphones have led to the development of Wireless Multimedia Sensor Networks (WMSN) as a class of wireless sensor networks which pose additional challenges. The transmission of imaging and video data needs routing protocols with both energy efficiency and Quality of Service (QoS) characteristics in order to guarantee the efficient use of the sensor nodes and effective access to the collected data. Also, with integration of real time applications in Wireless Senor Networks (WSNs), the use of QoS routing protocols is not only becoming a significant topic, but is also gaining the attention of researchers. In designing an efficient QoS routing protocol, the reliability and guarantee of end-to-end delay are critical events while conserving energy. Thus, considerable research has been focused on designing energy efficient and robust QoS routing protocols. In this paper, we present a state of the art research work based on real-time QoS routing protocols for WMSNs that have already been proposed. This paper categorizes the real-time QoS routing protocols into probabilistic and deterministic protocols. In addition, both categories are classified into soft and hard real time protocols by highlighting the QoS issues including the limitations and features of each protocol. Furthermore, we have compared the performance of mobility-aware query based real-time QoS routing protocols from each category using Network Simulator-2 (NS2). This paper also focuses on the design challenges and future research directions as well as highlights the characteristics of each QoS routing protocol.

  8. Providing QoS through machine-learning-driven adaptive multimedia applications.

    Science.gov (United States)

    Ruiz, Pedro M; Botía, Juan A; Gómez-Skarmeta, Antonio

    2004-06-01

    We investigate the optimization of the quality of service (QoS) offered by real-time multimedia adaptive applications through machine learning algorithms. These applications are able to adapt in real time their internal settings (i.e., video sizes, audio and video codecs, among others) to the unpredictably changing capacity of the network. Traditional adaptive applications just select a set of settings to consume less than the available bandwidth. We propose a novel approach in which the selected set of settings is the one which offers a better user-perceived QoS among all those combinations which satisfy the bandwidth restrictions. We use a genetic algorithm to decide when to trigger the adaptation process depending on the network conditions (i.e., loss-rate, jitter, etc.). Additionally, the selection of the new set of settings is done according to a set of rules which model the user-perceived QoS. These rules are learned using the SLIPPER rule induction algorithm over a set of examples extracted from scores provided by real users. We will demonstrate that the proposed approach guarantees a good user-perceived QoS even when the network conditions are constantly changing.

  9. Modelling the guaranteed QoS for wireless sensor networks: a network calculus approach

    Directory of Open Access Journals (Sweden)

    Yu Jianping

    2011-01-01

    Full Text Available Abstract Wireless sensor networks (WSNs became one of the high technology domains during the last 10 years. Real-time applications for them make it necessary to provide the guaranteed quality of service (QoS. The main contributions of this article are a system skeleton and a guaranteed QoS model that are suitable for the WSNs. To do it, we develop a sensor node model based on virtual buffer sharing and present a two-layer scheduling model using the network calculus. With the system skeleton, we develop a guaranteed QoS model, such as the upper bounds on buffer queue length/delay/effective bandwidth, and single-hop/multi-hops delay/jitter/effective bandwidth. Numerical results show the system skeleton and the guaranteed QoS model are scalable for different types of flows, including the self-similar traffic flows, and the parameters of flow regulators and service curves of sensor nodes affect them. Our proposal leads to buffer dimensioning, guaranteed QoS support and control in the WSNs.

  10. Integrating QoS and security functions in an IP-VPN gateway

    Science.gov (United States)

    Fan, Kuo-Pao; Chang, Shu-Hsin; Lin, Kuan-Ming; Pen, Mau-Jy

    2001-10-01

    IP-based Virtual Private Network becomes more and more popular. It can not only reduce the enterprise communication cost but also increase the revenue of the service provider. The common IP-VPN application types include Intranet VPN, Extranet VPN, and remote access VPN. For the large IP-VPN market, some vendors develop dedicated IP-VPN devices; while some vendors add the VPN functions into their existing network equipment such as router, access gateway, etc. The functions in the IP-VPN device include security, QoS, and management. The common security functions supported are IPSec (IP Security), IKE (Internet Key Exchange), and Firewall. The QoS functions include bandwidth control and packet scheduling. In the management component, policy-based network management is under standardization in IETF. In this paper, we discuss issues on how to integrate the QoS and security functions in an IP-VPN Gateway. We propose three approaches to do this. They are (1) perform Qos first (2) perform IPSec first and (3) reserve fixed bandwidth for IPSec. We also compare the advantages and disadvantages of the three proposed approaches.

  11. M ULTIPATH QOS A WARE R OUTING P ROTOCOL FOR ADHOC N ETWORK

    OpenAIRE

    Anupam Baliyan; Dr.Vikas Pareek

    2014-01-01

    Packet delivery ratio, delay, throughput, routing o verhead etc are the strict quality of service requi rements for applications in Ad hoc networks. So, the routin g protocol not only finds a suitable path but also the path should satisfy the QoS constraints also. Quality of services (QoS) aware routing is performed on the b asis of resource availability in the network and the flo w of QoS requirement. In this paper we developed a source routing protocol which...

  12. A Robust Service Selection Method Based on Uncertain QoS

    Directory of Open Access Journals (Sweden)

    Yanping Chen

    2016-01-01

    Full Text Available Nowadays, the number of Web services on the Internet is quickly increasing. Meanwhile, different service providers offer numerous services with the similar functions. Quality of Service (QoS has become an important factor used to select the most appropriate service for users. The most prominent QoS-based service selection models only take the certain attributes into account, which is an ideal assumption. In the real world, there are a large number of uncertain factors. In particular, at the runtime, QoS may become very poor or unacceptable. In order to solve the problem, a global service selection model based on uncertain QoS was proposed, including the corresponding normalization and aggregation functions, and then a robust optimization model adopted to transform the model. Experiment results show that the proposed method can effectively select services with high robustness and optimality.

  13. Assessing Measurements of QoS for global Cloud Computing Services

    DEFF Research Database (Denmark)

    Pedersen, Jens Myrup; Riaz, M. Tahir; Júnior, Joaquim Celestino

    2011-01-01

    Many global distributed cloud computing applications and services running over the Internet, between globally dispersed clients and servers, will require certain levels of Quality of Service (QoS) in order to deliver and give a sufficiently smooth user experience. This would be essential for real......-time streaming multimedia applications like online gaming and watching movies on a pay as you use basis hosted in a cloud computing environment. However, guaranteeing or even predicting QoS in global and diverse networks supporting complex hosting of application services is a very challenging issue that needs...... a stepwise refinement approach to be solved as the technology of cloud computing matures. In this paper, we investigate if latency in terms of simple Ping measurements can be used as an indicator for other QoS parameters such as jitter and throughput. The experiments were carried out on a global scale...

  14. Design and Analysis of QoS Routing Framework integrated with OLSR protocol for Multimedia Traffic in Mobile Adhoc Networks

    Directory of Open Access Journals (Sweden)

    S. Soni

    2017-06-01

    Full Text Available MANETs (Mobile Ad-hoc Networks is the self organizing wireless structure of mobile hosts. Wireless media is used for communication in MANETs. Considering the developing requirements for multimedia and real-time traffic applications in real world, QoS (Quality-of-Service support is essential in MANETs. But most of the characteristics of MANETs make QoS support a difficult problem. It is challenging to support QoS routing in MANET due to dynamic behavior and mobility of the hosts. The OLSR (Optimized Link State Routing protocol can be efficiently used in MANETs to provide QoS routing because of its dynamic MPR (Multi Point Relay selection criteria and proactive nature. In this paper, a design of QoS routing framework integrated with OLSR protocol is proposed and also analyzed using network simulator. Proposed QoS framework combines a bandwidth estimation algorithm with explicit resource reservation, QoS routing and connection admission control (CAC. OLSR protocol is extended for QoS framework to solve performance issues related to node mobility using cross layer approach. Results after simulation conclude about efficiency of the proposed QoS routing framework.

  15. Bio-Inspired Distributed Transmission Power Control Considering QoS Fairness in Wireless Body Area Sensor Networks.

    Science.gov (United States)

    Lee, Chan-Jae; Jung, Ji-Young; Lee, Jung-Ryun

    2017-10-14

    Recently, the development of wireless body area sensor network (WBASN) has accelerated due to the rapid development of wireless technology. In the WBASN environment, many WBASNs coexist where communication ranges overlap with each other, resulting in the possibility of interference. Although nodes in a WBASN typically operate at a low power level, to avoid adversely affecting the human body, high transmission rates may be required to support some applications. In addition to this, since many varieties of applications exist in the WBASN environment, each prospective user may have different quality of service (QoS) requirements. Hence, the following issues should be considered in the WBASN environment: (1) interference between adjacent WBASNs, which influences the performance of a specific system, and (2) the degree of satisfaction on the QoS of each user, i.e., the required QoS such as user throughput should be considered to ensure that all users in the network are provided with a fair QoS satisfaction. Thus, in this paper, we propose a transmission power adjustment algorithm that addresses interference problems and guarantees QoS fairness between users. First, we use a new utility function to measure the degree of the satisfaction on the QoS for each user. Then, the transmission power of each sensor node is calculated using the Cucker-Smale model, and the QoS satisfaction of each user is synchronized dispersively. The results of simulations show that the proposed algorithm performs better than existing algorithms, with respect to QoS fairness and energy efficiency.

  16. Priority Queues with Fractional Service for Tiered Delay QoS

    Directory of Open Access Journals (Sweden)

    Gary Chang

    2015-12-01

    Full Text Available Packet scheduling is key to quality of service (QoS capabilities of broadband wired and wireless networks. In a heterogeneous traffic environment, a comprehensive QoS packet scheduler must strike a balance between flow fairness and access delay. Many advanced packet scheduling solutions have targeted fair bandwidth allocation while protecting delay-constrained traffic by adding priority queue(s on top of a fair bandwidth scheduler. Priority queues are known to cause performance uncertainties and, thus, various modifications have been proposed. In this paper, we present a packet queueing engine dubbed Fractional Service Buffer (FSB, which, when coupled with a configurable flow scheduler, can achieve desired QoS objectives, such as fair throughputs and differentiated delay guarantees. Key performance metrics, such as delay limit and probability of delay limit violation, are derived as a function of key FSB parameters for each delay class in the packet queueing engine using diffusion approximations. OPNET simulations verify these analytical results.

  17. Middleware Support for Media Streaming Establishment Driven by User-oriented QoS Requirements

    NARCIS (Netherlands)

    Hesselman, C.E.W.; Widya, I.A.; van Halteren, Aart; Nieuwenhuis, Lambertus Johannes Maria; Scholten, Johan; van Sinderen, Marten J.

    2000-01-01

    The requirements for the QoS of distributed applications are traditionally expressed in terms of network oriented or systems oriented parameters. In general, the users of these services are not interested or capable of specifying the QoS of their services in such technical terms. In this paper, we

  18. Transmission Algorithm with QoS Considerations for a Sustainable MPEG Streaming Service

    Directory of Open Access Journals (Sweden)

    Sang-Hyong Kim

    2017-03-01

    Full Text Available With the proliferation of heterogeneous networks, there is a need to provide multimedia stream services in a sustainable manner. It is especially critical to maintain the Quality of Service (QoS standards. Existing multimedia streaming services have been studied to guarantee QoS on the receiving side. QoS has not been ensured due to the fact that the loss of streaming data to be transmitted has not been considered in network conditions. With an algorithm that considers the QoS and can reduce the overhead of the network, it will be possible to reduce the transmission error and wastage of communication network resources. In this paper, we propose a scheme that improves the reliability of multimedia transmissions by using an adaptive algorithm that switches between UDP (User Datagram Protocol and TCP (Transmission Control Protocol based on the size of the data. In addition, we present a method that retransmits essential portions of the multimedia data, thus improving transmission efficiency. We simulate an MPEG (Moving Picture Experts Group stream service and evaluate the performance of the proposed adaptive MPEG stream service.

  19. Providing end-to-end QoS for multimedia applications in 3G wireless networks

    Science.gov (United States)

    Guo, Katherine; Rangarajan, Samapth; Siddiqui, M. A.; Paul, Sanjoy

    2003-11-01

    As the usage of wireless packet data services increases, wireless carriers today are faced with the challenge of offering multimedia applications with QoS requirements within current 3G data networks. End-to-end QoS requires support at the application, network, link and medium access control (MAC) layers. We discuss existing CDMA2000 network architecture and show its shortcomings that prevent supporting multiple classes of traffic at the Radio Access Network (RAN). We then propose changes in RAN within the standards framework that enable support for multiple traffic classes. In addition, we discuss how Session Initiation Protocol (SIP) can be augmented with QoS signaling for supporting end-to-end QoS. We also review state of the art scheduling algorithms at the base station and provide possible extensions to these algorithms to support different classes of traffic as well as different classes of users.

  20. The extended TRIP supporting VoIP routing reservation with distributed QoS

    Science.gov (United States)

    Wang, Furong; Wu, Ye

    2004-04-01

    In this paper, an existing protocol, i.e. TRIP (Telephony Routing over IP) is developed to provide distributed QoS when making resource reservations for VoIP services such as H.323, SIP. Enhanced LSs (location servers) are deployed in ITADs (IP Telephony Administrative Domains) to take in charge of intra-domain routing policy because of small propagation price. It is an easy way to find an IP telephone route for intra-domain VoIP media association and simultaneously possess intra-domain load balancing features. For those routing reservations bridging domains, inter-domain routing policy is responsible for finding the shortest inter-domain route with enough resources. I propose the routing preference policy based on QoS price when the session traffic is shaped by a token bucket, related QoS messages, and message cooperation.

  1. Bidirectional QoS support for novelty detection applications based on hierarchical wireless sensor network model

    Science.gov (United States)

    Edwards, Mark; Hu, Fei; Kumar, Sunil

    2004-10-01

    The research on the Novelty Detection System (NDS) (called as VENUS) at the authors' universities has generated exciting results. For example, we can detect an abnormal behavior (such as cars thefts from the parking lot) from a series of video frames based on the cognitively motivated theory of habituation. In this paper, we would like to describe the implementation strategies of lower layer protocols for using large-scale Wireless Sensor Networks (WSN) to NDS with Quality-of-Service (QoS) support. Wireless data collection framework, consisting of small and low-power sensor nodes, provides an alternative mechanism to observe the physical world, by using various types of sensing capabilities that include images (and even videos using Panoptos), sound and basic physical measurements such as temperature. We do not want to lose any 'data query command' packets (in the downstream direction: sink-to-sensors) or have any bit-errors in them since they are so important to the whole sensor network. In the upstream direction (sensors-to-sink), we may tolerate the loss of some sensing data packets. But the 'interested' sensing flow should be assigned a higher priority in terms of multi-hop path choice, network bandwidth allocation, and sensing data packet generation frequency (we hope to generate more sensing data packet for that novel event in the specified network area). The focus of this paper is to investigate MAC-level Quality of Service (QoS) issue in Wireless Sensor Networks (WSN) for Novelty Detection applications. Although QoS has been widely studied in other types of networks including wired Internet, general ad hoc networks and mobile cellular networks, we argue that QoS in WSN has its own characteristics. In wired Internet, the main QoS parameters include delay, jitter and bandwidth. In mobile cellular networks, two most common QoS metrics are: handoff call dropping probability and new call blocking probability. Since the main task of WSN is to detect and report

  2. Desempeño de la calidad del servicio (QoS sobre IPv6

    Directory of Open Access Journals (Sweden)

    Octavio José Salcedo Parra

    2011-06-01

    Full Text Available New applications such as VoIP, e-commerce and video conferencing are sensitive to network performance, making the network capacity to provide quality of service is increasingly important. IPv6 was developed to solve some of the problems of IPv4, such as QoS, security and IP address exhaustion. Current IP networks provide better trafficdelivery effort, therefore, offer no guarantee of quality service. However, there are services, including voice, with stringent requirements for delay and delay variation (jitter, which makes it necessary to add functionality to IP networks based on this protocol are capable of supporting such services. For its part, IPv6 uses 2 fields that can be used to implement QoS, which are: Flow Label and Traffic Class. This article describes the mechanisms and architectures that are used to provide QoS on a network. Later, you specify the features that use both IPv4 and IPv6 to implement QoS. In the last sections present the results of the comparison of 2 scenarios, which are evaluated.

  3. QoS Routing in Ad-Hoc Networks Using GA and Multi-Objective Optimization

    Directory of Open Access Journals (Sweden)

    Admir Barolli

    2011-01-01

    Full Text Available Much work has been done on routing in Ad-hoc networks, but the proposed routing solutions only deal with the best effort data traffic. Connections with Quality of Service (QoS requirements, such as voice channels with delay and bandwidth constraints, are not supported. The QoS routing has been receiving increasingly intensive attention, but searching for the shortest path with many metrics is an NP-complete problem. For this reason, approximated solutions and heuristic algorithms should be developed for multi-path constraints QoS routing. Also, the routing methods should be adaptive, flexible, and intelligent. In this paper, we use Genetic Algorithms (GAs and multi-objective optimization for QoS routing in Ad-hoc Networks. In order to reduce the search space of GA, we implemented a search space reduction algorithm, which reduces the search space for GAMAN (GA-based routing algorithm for Mobile Ad-hoc Networks to find a new route. We evaluate the performance of GAMAN by computer simulations and show that GAMAN has better behaviour than GLBR (Genetic Load Balancing Routing.

  4. Research on distributed QOS routing algorithm based on TCP/IP

    Science.gov (United States)

    Liu, Xiaoyue; Chen, Yongqiang

    2011-10-01

    At present, network environment follow protocol standard of IPV4 is intended to do the best effort of network to provide network applied service for users, however, not caring about service quality.Thus the packet loss rate is high, it cannot reach an ideal applied results. This article through the establishment of mathematical model, put forward a new distributed multi QOS routing algorithm, given the realization process of this distributed QOS routing algorithm, and simulation was carried out by simulation software. The results show the proposed algorithm can improve the utilization rate of network resources and the service quality of network application.

  5. Buffer Management of Multi-Queue QoS Switches with Class Segregation

    OpenAIRE

    Itoh, Toshiya; Yoshimoto, Seiji

    2013-01-01

    In this paper, we focus on buffer management of multi-queue QoS switches in which packets of different values are segregated in different queues. Our model consists of $m$ queues and $m$ packet values $0 < v_{1} < v_{2} < ... < v_{m}$. Recently, Al-Bawani and Souza [IPL 113(4), pp.145-150, 2013] presented an online algorithm GREEDY for buffer management of multi-queue QoS switches with class segregation and showed thatif $m$ queues have the same size, then the competitive ratio of GREEDY is $...

  6. QoS INVESTIGATION ON MOODLE’S VIDEO CONFERENCE

    Directory of Open Access Journals (Sweden)

    LINAWATI LINAWATI

    2011-06-01

    Full Text Available Learning Management System (LMS supports e-learning as a distant learning. Moodle is one of open source LMS applications that allow embedding multimedia into learning activity in a course, such as video conference session. The paper investigates quality of service (QoS of video conference session embedded in Moodle, i.e. end-to-end delay, jitter, throughput, packet loss and PSNR. Three scenarios were implemented in the experiment. The scenarios were applied on both wire and wireless transmission, and p2p and p2m connections. The investigation results show that the QoS of video conference session meets the standards issued by ITU-T G.1010 and G.114, for minimum bandwidth of 128 kbps. Thus the application of video conferencing that is integrated in Moodle can run well with minimum bandwidth of 128 Kbps. 

  7. Communication Framework for Tele-rehabilitation Systems with QoS Guarantee

    Directory of Open Access Journals (Sweden)

    Dandanov Nikolay

    2017-01-01

    Full Text Available Nowadays, there is great interest in developing telemedicine technologies. These technologies will provide health care from distance swiftly and lightly, as well as reduce the expenses for activities, such as rehabilitation. Telemedicine applications are possible due to the advances in information technologies and the ever-expanding communication network infrastructure. The network characteristics bandwidth, packet loss, latency, jitter and policies are crucial for the performance of tele-rehabilitation systems. Because in tele-rehabilitation human lives are at stake, guaranteeing the Quality of Service (QoS is important. In this paper, an approach for assuring the QoS for information transmission in tele-rehabilitation systems is proposed.

  8. A Personalized QoS Prediction Approach for CPS Service Recommendation Based on Reputation and Location-Aware Collaborative Filtering.

    Science.gov (United States)

    Kuang, Li; Yu, Long; Huang, Lan; Wang, Yin; Ma, Pengju; Li, Chuanbin; Zhu, Yujia

    2018-05-14

    With the rapid development of cyber-physical systems (CPS), building cyber-physical systems with high quality of service (QoS) has become an urgent requirement in both academia and industry. During the procedure of building Cyber-physical systems, it has been found that a large number of functionally equivalent services exist, so it becomes an urgent task to recommend suitable services from the large number of services available in CPS. However, since it is time-consuming, and even impractical, for a single user to invoke all of the services in CPS to experience their QoS, a robust QoS prediction method is needed to predict unknown QoS values. A commonly used method in QoS prediction is collaborative filtering, however, it is hard to deal with the data sparsity and cold start problem, and meanwhile most of the existing methods ignore the data credibility issue. Thence, in order to solve both of these challenging problems, in this paper, we design a framework of QoS prediction for CPS services, and propose a personalized QoS prediction approach based on reputation and location-aware collaborative filtering. Our approach first calculates the reputation of users by using the Dirichlet probability distribution, so as to identify untrusted users and process their unreliable data, and then it digs out the geographic neighborhood in three levels to improve the similarity calculation of users and services. Finally, the data from geographical neighbors of users and services are fused to predict the unknown QoS values. The experiments using real datasets show that our proposed approach outperforms other existing methods in terms of accuracy, efficiency, and robustness.

  9. Research on the business QoS and trustworthy and controllable strategies mechanism for energy internet

    Science.gov (United States)

    Zhang, Geng; Lu, Meiling; Zhang, Dahua; Zhou, Liang; Li, Likang

    2017-01-01

    Energy internet is a kind of power sharing network, which can realize the bidirectional flow of energy information on the basis of the existing power grid. It puts forward higher requirements for reliability and controllability of information communication, and all kinds of business QoS of the backbone network. So the research of business QoS and trustworthy and controllable strategies mechanism have an important significance for the development of energy internet. This paper mainly studies how to use the software defined network (SDN) to achieve business QoS, and provide QoS support for all kinds of business of the energy internet. Combined with the current development situation of the energy internet in our country, this paper researches the trustworthy and controllable strategies mechanism for energy internet, and proposes the transition scheme of the IPv6 credible network architecture based on SDN. This coordinates the contradiction between the growing demand for energy internet applications and the limitations of the energy internet technology itself.

  10. QoS Support Polling Scheme for Multimedia Traffic in Wireless LAN MAC Protocol

    Institute of Scientific and Technical Information of China (English)

    YANG Zhijun; ZHAO Dongfeng

    2008-01-01

    Quality of service (QoS) support is a key attribute for multimedia traffic including video, voice, and data in wireless local area networks (LANs) but is limited in 802.11-based wireless LANs. A polling-based scheme called the point coordination function (PCF) was developed for 802.11 LANs to support the trans-mission of multimedia traffic. However, the PCF is not able to meet the desired practical traffic differentiation requirements for real-time data. This paper describes a QoS support polling scheme based on the IEEE 802.11 medium access control (MAC) protocol. The scheme uses a two-level polling mechanism with the QoS classes differentiated by two different access policies. Stations with higher priority traffic such as key or real-time data form the first level and can access the common channel through an exhaustive access policy. Other stations with lower priority traffic form the second level and can access the channel through a gated access policy. A system model based on imbedded Markov chain theory and a generation function were setup to explicitly analyze the mean information packet waiting time of the two-level polling scheme. Theo-retical and simulation results show that the new scheme efficiently differentiates services to guarantee better QoS and system stability.

  11. ALPHA: Proposal of Mapping QoS Parameters between UPnP Home Network and GMPLS Access

    DEFF Research Database (Denmark)

    Brewka, Lukasz Jerzy; Sköldström, Pontus; Gavler, Anders

    2011-01-01

    This paper is treating the interdomain QoS signaling between the home and access domains with a focus on applying it for providing QoS between a UPnP-QoS based home network and GMPLS based access network. The work presented here is defining a possible approach for an interface between UPn...

  12. Optimal capacity and buffer size estimation under Generalized Markov Fluids Models and QoS parameters

    International Nuclear Information System (INIS)

    Bavio, José; Marrón, Beatriz

    2014-01-01

    Quality of service (QoS) for internet traffic management requires good traffic models and good estimation of sharing network resource. A link of a network processes all traffic and it is designed with certain capacity C and buffer size B. A Generalized Markov Fluid model (GMFM), introduced by Marrón (2011), is assumed for the sources because describes in a versatile way the traffic, allows estimation based on traffic traces, and also consistent effective bandwidth estimation can be done. QoS, interpreted as buffer overflow probability, can be estimated for GMFM through the effective bandwidth estimation and solving the optimization problem presented in Courcoubetis (2002), the so call inf-sup formulas. In this work we implement a code to solve the inf-sup problem and other optimization related with it, that allow us to do traffic engineering in links of data networks to calculate both, minimum capacity required when QoS and buffer size are given or minimum buffer size required when QoS and capacity are given

  13. Cross-layer protocol design for QoS optimization in real-time wireless sensor networks

    Science.gov (United States)

    Hortos, William S.

    2010-04-01

    The metrics of quality of service (QoS) for each sensor type in a wireless sensor network can be associated with metrics for multimedia that describe the quality of fused information, e.g., throughput, delay, jitter, packet error rate, information correlation, etc. These QoS metrics are typically set at the highest, or application, layer of the protocol stack to ensure that performance requirements for each type of sensor data are satisfied. Application-layer metrics, in turn, depend on the support of the lower protocol layers: session, transport, network, data link (MAC), and physical. The dependencies of the QoS metrics on the performance of the higher layers of the Open System Interconnection (OSI) reference model of the WSN protocol, together with that of the lower three layers, are the basis for a comprehensive approach to QoS optimization for multiple sensor types in a general WSN model. The cross-layer design accounts for the distributed power consumption along energy-constrained routes and their constituent nodes. Following the author's previous work, the cross-layer interactions in the WSN protocol are represented by a set of concatenated protocol parameters and enabling resource levels. The "best" cross-layer designs to achieve optimal QoS are established by applying the general theory of martingale representations to the parameterized multivariate point processes (MVPPs) for discrete random events occurring in the WSN. Adaptive control of network behavior through the cross-layer design is realized through the parametric factorization of the stochastic conditional rates of the MVPPs. The cross-layer protocol parameters for optimal QoS are determined in terms of solutions to stochastic dynamic programming conditions derived from models of transient flows for heterogeneous sensor data and aggregate information over a finite time horizon. Markov state processes, embedded within the complex combinatorial history of WSN events, are more computationally

  14. Analisa Horizontal Handover Terhadap Qos Layanan Streaming Multimedia E-Learning Pada Jaringan WLAN 802.11

    Directory of Open Access Journals (Sweden)

    I M.O. Widyantara

    2015-06-01

    Full Text Available In this globalization era, the state of the user who no longer occupies in a single place, but always moving, it is necessary to continuity of communication that will cause a handover. This paper intends to analyze the effect of 802.11 WLAN horizontal handover to the QoS of streaming e-learning. Methods of data collection process using the Cisco 3500 series access point that supports handover with existing network systems, ad-hoc network and type of hard handover. The results of the data analysis showed that the handover process is able to improve the QoS by gradually restored gradually, to get back to normal QoS

  15. Mixed integer nonlinear programming model of wireless pricing scheme with QoS attribute of bandwidth and end-to-end delay

    Science.gov (United States)

    Irmeilyana, Puspita, Fitri Maya; Indrawati

    2016-02-01

    The pricing for wireless networks is developed by considering linearity factors, elasticity price and price factors. Mixed Integer Nonlinear Programming of wireless pricing model is proposed as the nonlinear programming problem that can be solved optimally using LINGO 13.0. The solutions are expected to give some information about the connections between the acceptance factor and the price. Previous model worked on the model that focuses on bandwidth as the QoS attribute. The models attempt to maximize the total price for a connection based on QoS parameter. The QoS attributes used will be the bandwidth and the end to end delay that affect the traffic. The maximum goal to maximum price is achieved when the provider determine the requirement for the increment or decrement of price change due to QoS change and amount of QoS value.

  16. GEMSS: grid-infrastructure for medical service provision.

    Science.gov (United States)

    Benkner, S; Berti, G; Engelbrecht, G; Fingberg, J; Kohring, G; Middleton, S E; Schmidt, R

    2005-01-01

    The European GEMSS Project is concerned with the creation of medical Grid service prototypes and their evaluation in a secure service-oriented infrastructure for distributed on demand/supercomputing. Key aspects of the GEMSS Grid middleware include negotiable QoS support for time-critical service provision, flexible support for business models, and security at all levels in order to ensure privacy of patient data as well as compliance to EU law. The GEMSS Grid infrastructure is based on a service-oriented architecture and is being built on top of existing standard Grid and Web technologies. The GEMSS infrastructure offers a generic Grid service provision framework that hides the complexity of transforming existing applications into Grid services. For the development of client-side applications or portals, a pluggable component framework has been developed, providing developers with full control over business processes, service discovery, QoS negotiation, and workflow, while keeping their underlying implementation hidden from view. A first version of the GEMSS Grid infrastructure is operational and has been used for the set-up of a Grid test-bed deploying six medical Grid service prototypes including maxillo-facial surgery simulation, neuro-surgery support, radio-surgery planning, inhaled drug-delivery simulation, cardiovascular simulation and advanced image reconstruction. The GEMSS Grid infrastructure is based on standard Web Services technology with an anticipated future transition path towards the OGSA standard proposed by the Global Grid Forum. GEMSS demonstrates that the Grid can be used to provide medical practitioners and researchers with access to advanced simulation and image processing services for improved preoperative planning and near real-time surgical support.

  17. An Analysis of QoS in ZigBee Network Based on Deviated Node Priority

    Directory of Open Access Journals (Sweden)

    Md. Jaminul Haque Biddut

    2016-01-01

    Full Text Available ZigBee is an IEEE 802.15.4 standardized communication protocol. It forms a flawless Wireless Sensor Network (WSN standard for interoperability at all levels of the network, particularly the application level which most closely touches the user. A large number of devices from different vendors can work seamlessly. These devices act as a network and send huge data traffic to the Coordinator. End devices at different zones have different roles in communication with each other. There has been a lack in executing their requests in a synchronized way based on task priority. This lack leads to massive data traffic loss and degrades the Quality of Service (QoS. One of the challenges is to analyze the QoS parameters in ZigBee network that help to detect the overall network performance. The contribution of this paper is twofold; first, a ZigBee Network is implemented based on node priority. It demonstrates a method to generate a new priority of devices with respect to their existing priority and zones’ priority as well. Second, the QoS is analyzed based on the new priority status for tasks preference purposes. The outcome of this paper shows that the QoS of the network is more conspicuous than non-priority based network.

  18. A Novel Prioritization Scheme to Improve QoS in IEEE 802.11e Networks

    Directory of Open Access Journals (Sweden)

    Navid Tadayon

    2010-01-01

    Full Text Available IEEE 802.11 WLAN utilizes a distributed function at its MAC layer, namely, DCF to access the wireless medium. Due to its distributed nature, DCF is able to guarantee working stability in a wireless medium while maintaining the assembling and maintenance cost in a low level. However, DCF is inefficient in dealing with real-time traffics due to its incapability on providing QoS. IEEE 802.11e was introduced as a supplementary standard to cope with this problem. This standard introduces an Enhanced Distributed Coordination Function (EDCF that works based on diff-Serve model and can serve multiple classes of traffics (by using different prioritizations schemes. With the emergence of new time-sensitive applications, EDCF has proved to be yet inefficient in dealing with these kinds of traffics because it could not provide network with well-differentiated QoS. In this study, we propose a novel prioritization scheme to improve QoS level in IEEE 802.11e network. In this scheme, we replace Uniform PDF with Gamma PDF, which has salient differentiating properties. We investigate the suitability and superiority of this scheme on furnishing network with well-differentiated QoS using probabilistic analysis. We strengthen our claims by extensive simulation runs.

  19. OPNET Modeler Simulation Testing of the New Model Used to Cooperation Between QoS and Security Mechanisms

    Directory of Open Access Journals (Sweden)

    Jan Papaj

    2012-01-01

    Full Text Available In this article the performance analysis of the new model, used to integration between QoS and Security, is introduced. OPNET modeler simulation testing of the new model with comparation with the standard model is presented. This new model enables the process of cooperation between QoS and Security in MANET. The introduction how the model is implemented to the simulation OPNET modeler is also showed. Model provides possibilities to integration and cooperation of QoS and security by the cross layer design (CLD with modified security service vector (SSV. An overview of the simulation tested of the new model, comparative study in mobile ad-hoc networks, describe requirements and directions for adapted solutions are presented. Main idea of the testing is to show how QoS and Security related services could be provided simultaneously with using minimal interfering with each service.

  20. QoS Negotiation in Real-Time Systems and its Application to Automated Flight Control

    Science.gov (United States)

    2000-11-01

    QoS Negotiation in Real - Time Systems and Its Application to Automated Flight Control Tarek F. Abdelzaher, Member, IEEE, Ella M. Atkins, Member, IEEE...been committed to those that arrived earlier. In hard- real - time systems , a static analysis may be performed to guarantee a priori that all requests be...DATE 2000 2. REPORT TYPE 3. DATES COVERED 00-00-2000 to 00-00-2000 4. TITLE AND SUBTITLE QoS Negotiation in Real - Time Systems and its

  1. QoS testing of service-based applications

    OpenAIRE

    Driss , Maha; Jamoussi , Yassine; Ben Ghézala , Henda Hajjami

    2008-01-01

    International audience; Web services (WSs) are becoming increasingly popular because of their potential in several application domains including e-Enterprise, e-Business, e-Government, and e-Science. Based on open XML standards, WS technology allows the construction of massively distributed and loosely coupled applications. A service composition mechanism should satisfy not only functional properties but also non-functional Quality of Service (QoS) ones. In this paper, we introduce a discrete...

  2. Further improvements in competitive guarantees for QoS buffering

    NARCIS (Netherlands)

    Bansal, N.; Fleischer, L.K.; Kimbrel, T.; Mahdian, M.; Schieber, B.; Sviridenko, M.; Diaz, J.; Karhumäki, J.; Lepistö, A.; Sannella, D.

    2004-01-01

    We study the behavior of algorithms for buffering packets weighted by different levels of Quality of Service (QoS) guarantees in a single queue. Buffer space is limited, and packet loss occurs when the buffer overflows. We describe a modification of the previously proposed ``preemptive greedy{''}

  3. On capacity tradeoffs in secure DS-CDMA packet communications with QOS constraints

    International Nuclear Information System (INIS)

    Sattar, F.; Mufti, M.

    2012-01-01

    This paper presents a mathematical framework for analysis of effect of counter mode (CTR) encryption on the traffic capacity of packet communication systems based on direct-sequence, code-division, multiple-access (DS-CDMA). We specify QoS constraints in terms of minimum acceptable mean opinion score (MOS) of voice payload, maximum permissible resource utilization for CTR-mode re-keying and DS-CDMA processing gain. We quantify the trade-offs in system capacity as a function of these constraints. Results show that application of CTR encryption causes error expansion and respecting the QoS constraints while satisfying the desired encryption parameters results in reduction of traffic capacity. (author)

  4. Survey on Monitoring and Quality Controlling of the Mobile Biosignal Delivery.

    Science.gov (United States)

    Pawar, Pravin A; Edla, Damodar R; Edoh, Thierry; Shinde, Vijay; van Beijnum, Bert-Jan

    2017-10-31

    A Mobile Patient Monitoring System (MPMS) acquires patient's biosignals and transmits them using wireless network connection to the decision-making module or healthcare professional for the assessment of patient's condition. A variety of wireless network technologies such as wireless personal area networks (e.g., Bluetooth), mobile ad-hoc networks (MANET), and infrastructure-based networks (e.g., WLAN and cellular networks) are in practice for biosignals delivery. The wireless network quality-of-service (QoS) requirements of biosignals delivery are mainly specified in terms of required bandwidth, acceptable delay, and tolerable error rate. An important research challenge in the MPMS is how to satisfy QoS requirements of biosignals delivery in the environment characterized by patient mobility, deployment of multiple wireless network technologies, and variable QoS characteristics of the wireless networks. QoS requirements are mainly application specific, while available QoS is largely dependent on QoS provided by wireless network in use. QoS provisioning refers to providing support for improving QoS experience of networked applications. In resource poor conditions, application adaptation may also be required to make maximum use of available wireless network QoS. This survey paper presents a survey of recent developments in the area of QoS provisioning for MPMS. In particular, our contributions are as follows: (1) overview of wireless networks and network QoS requirements of biosignals delivery; (2) survey of wireless networks' QoS performance evaluation for the transmission of biosignals; and (3) survey of QoS provisioning mechanisms for biosignals delivery in MPMS. We also propose integrating end-to-end QoS monitoring and QoS provisioning strategies in a mobile patient monitoring system infrastructure to support optimal delivery of biosignals to the healthcare professionals.

  5. ANCS: Achieving QoS through Dynamic Allocation of Network Resources in Virtualized Clouds

    Directory of Open Access Journals (Sweden)

    Cheol-Ho Hong

    2016-01-01

    Full Text Available To meet the various requirements of cloud computing users, research on guaranteeing Quality of Service (QoS is gaining widespread attention in the field of cloud computing. However, as cloud computing platforms adopt virtualization as an enabling technology, it becomes challenging to distribute system resources to each user according to the diverse requirements. Although ample research has been conducted in order to meet QoS requirements, the proposed solutions lack simultaneous support for multiple policies, degrade the aggregated throughput of network resources, and incur CPU overhead. In this paper, we propose a new mechanism, called ANCS (Advanced Network Credit Scheduler, to guarantee QoS through dynamic allocation of network resources in virtualization. To meet the various network demands of cloud users, ANCS aims to concurrently provide multiple performance policies; these include weight-based proportional sharing, minimum bandwidth reservation, and maximum bandwidth limitation. In addition, ANCS develops an efficient work-conserving scheduling method for maximizing network resource utilization. Finally, ANCS can achieve low CPU overhead via its lightweight design, which is important for practical deployment.

  6. GRIDCC: A Real-Time Grid Workflow System with QoS

    Directory of Open Access Journals (Sweden)

    A. Stephen McGough

    2007-01-01

    Full Text Available The over-arching aim of Grid computing is to move computational resources from individual institutions where they can only be used for in-house work, to a more open vision of vast online ubiquitous `virtual computational' resources which support individuals and collaborative projects. A major step towards realizing this vision is the provision of instrumentation – such as telescopes, accelerators or electrical power stations – as Grid resources, and the tools to manage these resources online. The GRIDCC project attempts to satisfy these requirements by providing the following four co-dependent components; a flexible wrapper for publishing instruments as Grid resources; workflow support for the orchestration of multiple Grid resources in a timely manner; the machinery to make reservation agreements on Grid resources; and the facility to satisfy quality of service (QoS requirements on elements within workflows. In this paper we detail the set of services developed as part of the GRIDCC project to provide the last three of these components. We provide a detailed architecture for these services along with experimental results from load testing experiments. These services are currently deployed as a test-bed at a number of institutions across Europe, and are poised to provide a 'virtual lab' to production level applications.

  7. Dynamic QoS Evaluation of Multimedia Contents in Wireless Networks by “Double-Boomerang” Watermarking

    Directory of Open Access Journals (Sweden)

    Gaetano Giunta

    2010-03-01

    Full Text Available This work presents a cooperative network-aware processing of multimedia content for dynamic quality of service management in wireless IP networks. Our technique can be also used for quality control in UMTS environments, exploiting the tracing watermarking recently introduced in literature. In this work, we use the transmitted video-sequences to monitor the QoS in a videoconference call. The video-sequence of every active user travels on the communication link, one time as video (transparent mode, one time as watermark (hidden mode describing a boomerang trajectory. The results obtained through our simulation trials confirm the validity of such approach. In fact, the advantages of distributing the management process are (i an easier and more precise localization of the cause of QoS problems, (ii a better knowledge of local situations, (iii a lower complexity for a single QoS agent and (iv an increase in possible actions.

  8. Impact of VoIP and QoS on Open and Distance Learning

    Directory of Open Access Journals (Sweden)

    Sanjay JASOLA

    2006-07-01

    Full Text Available Voice over Internet Protocol (VoIP is becoming a reality in many organizations. The potential for mobility in voice over wi-fi networks will derive demand for the technology. Wireless VoIP is poised to rival VoIP as an alternative telephony tool. Internet has been used to transport data in the form of packet. In the past, Internet did not support any kind of sophisticated quality of service (QoS mechanism. Although the type of service (TOS field in the Internet protocol (IP header has been existing and has been allowing the differentiated treatment of packets, it was never really used on a large scale. The voice is sensitive to delay and jitter so bandwidth must be guaranteed while transporting it. With the extensive use of Internet for carrying voice, there is a need to add QoS functionality in it. QoS with reference to VoIP has been discussed in the paper. Limited bandwidth and network latency are the issues which need to be considered while using wireless LAN for packetized voice data. Efforts of standards like 802.11e which will take care of these issues, have also been explored. The impact of these technologies on distance education has also been explored in the paper.

  9. An Efficient and QoS Supported Multichannel MAC Protocol for Vehicular Ad Hoc Networks.

    Science.gov (United States)

    Song, Caixia; Tan, Guozhen; Yu, Chao

    2017-10-09

    Vehicular Ad Hoc Networks (VANETs) employ multichannel to provide a variety of safety and non-safety (transport efficiency and infotainment) applications, based on the IEEE 802.11p and IEEE 1609.4 protocols. Different types of applications require different levels Quality-of-Service (QoS) support. Recently, transport efficiency and infotainment applications (e.g., electronic map download and Internet access) have received more and more attention, and this kind of applications is expected to become a big market driver in a near future. In this paper, we propose an Efficient and QoS supported Multichannel Medium Access Control (EQM-MAC) protocol for VANETs in a highway environment. The EQM-MAC protocol utilizes the service channel resources for non-safety message transmissions during the whole synchronization interval, and it dynamically adjusts minimum contention window size for different non-safety services according to the traffic conditions. Theoretical model analysis and extensive simulation results show that the EQM-MAC protocol can support QoS services, while ensuring the high saturation throughput and low transmission delay for non-safety applications.

  10. An Efficient and QoS Supported Multichannel MAC Protocol for Vehicular Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Caixia Song

    2017-10-01

    Full Text Available Vehicular Ad Hoc Networks (VANETs employ multichannel to provide a variety of safety and non-safety (transport efficiency and infotainment applications, based on the IEEE 802.11p and IEEE 1609.4 protocols. Different types of applications require different levels Quality-of-Service (QoS support. Recently, transport efficiency and infotainment applications (e.g., electronic map download and Internet access have received more and more attention, and this kind of applications is expected to become a big market driver in a near future. In this paper, we propose an Efficient and QoS supported Multichannel Medium Access Control (EQM-MAC protocol for VANETs in a highway environment. The EQM-MAC protocol utilizes the service channel resources for non-safety message transmissions during the whole synchronization interval, and it dynamically adjusts minimum contention window size for different non-safety services according to the traffic conditions. Theoretical model analysis and extensive simulation results show that the EQM-MAC protocol can support QoS services, while ensuring the high saturation throughput and low transmission delay for non-safety applications.

  11. Cooperative Optimization QoS Cloud Routing Protocol Based on Bacterial Opportunistic Foraging and Chemotaxis Perception for Mobile Internet

    Directory of Open Access Journals (Sweden)

    Shujuan Wang

    2015-01-01

    Full Text Available In order to strengthen the mobile Internet mobility management and cloud platform resources utilization, optimizing the cloud routing efficiency is established, based on opportunistic bacterial foraging bionics, and puts forward a chemotaxis perception of collaborative optimization QoS (Quality of Services cloud routing mechanism. The cloud routing mechanism is based on bacterial opportunity to feed and bacterial motility and to establish the data transmission and forwarding of the bacterial population behavior characteristics. This mechanism is based on the characteristics of drug resistance of bacteria and the structure of the field, and through many iterations of the individual behavior and population behavior the bacteria can be spread to the food gathering area with a certain probability. Finally, QoS cloud routing path would be selected and optimized based on bacterial bionic optimization and hedge mapping relationship between mobile Internet node and bacterial population evolution iterations. Experimental results show that, compared with the standard dynamic routing schemes, the proposed scheme has shorter transmission delay, lower packet error ratio, QoS cloud routing loading, and QoS cloud route request overhead.

  12. Multi-Class load balancing scheme for QoS and energy ...

    African Journals Online (AJOL)

    Multi-Class load balancing scheme for QoS and energy conservation in cloud computing. ... If you would like more information about how to print, save, and work with PDFs, Highwire Press provides a helpful Frequently Asked Questions about PDFs. Alternatively, you can download the PDF file directly to your computer, from ...

  13. A framework for QoS & mobility in the Internet next generation

    NARCIS (Netherlands)

    Rexhepi, Vlora; Karagiannis, Georgios; Heijenk, Geert; Pras, Aiko

    2000-01-01

    It is expected that the Internet next generation architecture will support applications with different quality of service requirements, independently of whether their location is fixed or mobile. However, enabling QoS in Internet is a tough challenge, and it gets even tougher when the mobile

  14. A framework for QoS & mobility in the Internet next generation

    NARCIS (Netherlands)

    Karagiannis, Georgios; Rexhepi, Vlora; Heijenk, Geert

    It is expected that the next generation Internet architecture will support applications with different quality of service requirements, independently of whether their location is fixed or movable. However, enabling QoS in Internet is a tough challenge, and it gets even tougher when the mobile

  15. Dynamic Resource Allocation and QoS Control Capabilities of the Japanese Academic Backbone Network

    Directory of Open Access Journals (Sweden)

    Michihiro Aoki

    2010-08-01

    Full Text Available Dynamic resource control capabilities have become increasingly important for academic networks that must support big scientific research projects at the same time as less data intensive research and educational activities. This paper describes the dynamic resource allocation and QoS control capabilities of the Japanese academic backbone network, called SINET3, which supports a variety of academic applications with a wide range of network services. The article describes the network architecture, networking technologies, resource allocation, QoS control, and layer-1 bandwidth on-demand services. It also details typical services developed for scientific research, including the user interface, resource control, and management functions, and includes performance evaluations.

  16. QoS Differential Scheduling in Cognitive-Radio-Based Smart Grid Networks: An Adaptive Dynamic Programming Approach.

    Science.gov (United States)

    Yu, Rong; Zhong, Weifeng; Xie, Shengli; Zhang, Yan; Zhang, Yun

    2016-02-01

    As the next-generation power grid, smart grid will be integrated with a variety of novel communication technologies to support the explosive data traffic and the diverse requirements of quality of service (QoS). Cognitive radio (CR), which has the favorable ability to improve the spectrum utilization, provides an efficient and reliable solution for smart grid communications networks. In this paper, we study the QoS differential scheduling problem in the CR-based smart grid communications networks. The scheduler is responsible for managing the spectrum resources and arranging the data transmissions of smart grid users (SGUs). To guarantee the differential QoS, the SGUs are assigned to have different priorities according to their roles and their current situations in the smart grid. Based on the QoS-aware priority policy, the scheduler adjusts the channels allocation to minimize the transmission delay of SGUs. The entire transmission scheduling problem is formulated as a semi-Markov decision process and solved by the methodology of adaptive dynamic programming. A heuristic dynamic programming (HDP) architecture is established for the scheduling problem. By the online network training, the HDP can learn from the activities of primary users and SGUs, and adjust the scheduling decision to achieve the purpose of transmission delay minimization. Simulation results illustrate that the proposed priority policy ensures the low transmission delay of high priority SGUs. In addition, the emergency data transmission delay is also reduced to a significantly low level, guaranteeing the differential QoS in smart grid.

  17. Fairness as a QoS Measure for Web Services

    Directory of Open Access Journals (Sweden)

    Stefano Bistarelli

    2009-06-01

    Full Text Available Service Oriented Architectures (SOAs are component-based architectures, characterized by reusability, modularization and composition, usually offered by HTTP (web services and often equipped with a Quality of Services (QoS measure. In order to guarantee the fairness property to each client requesting a service, we propose a fair version of the (Soft Concurrent Constraint language to deal with the negotiation phases of the Service Level Agreement (SLA protocol.

  18. Collaborative QoS Prediction for Mobile Service with Data Filtering and SlopeOne Model

    Directory of Open Access Journals (Sweden)

    Yuyu Yin

    2017-01-01

    Full Text Available The mobile service is a widely used carrier for mobile applications. With the increase of the number of mobile services, for service recommendation and selection, the nonfunctional properties (also known as quality of service, QoS become increasingly important. However, in many cases, the number of mobile services invoked by a user is quite limited, which leads to the large number of missing QoS values. In recent years, many prediction algorithms, such as algorithms extended from collaborative filtering (CF, are proposed to predict QoS values. However, the ideas of most existing algorithms are borrowed from the recommender system community, not specific for mobile service. In this paper, we first propose a data filtering-extended SlopeOne model (filtering-based CF, which is based on the characteristics of a mobile service and considers the relation with location. Also, using the data filtering technique in FB-CF and matrix factorization (MF, this paper proposes another model FB-MF (filtering-based MF. We also build an ensemble model, which combines the prediction results of FB-CF model and FB-MF model. We conduct sufficient experiments, and the experimental results demonstrate that our models outperform all compared methods and achieve good results in high data sparsity scenario.

  19. Traffic Agents for Improving QoS in Mixed Infrastructure and Ad Hoc Modes Wireless LAN

    Directory of Open Access Journals (Sweden)

    Yuan Hai-Feng

    2006-01-01

    Full Text Available As an important complement to infrastructured wireless networks, mobile ad hoc networks (MANET are more flexible in providing wireless access services, but more difficult in meeting different quality of service (QoS requirements for mobile customers. Both infrastructure and ad hoc network structures are supported in wireless local area networks (WLAN, which can offer high data-rate wireless multimedia services to the mobile stations (MSs in a limited geographical area. For those out-of-coverage MSs, how to effectively connect them to the access point (AP and provide QoS support is a challenging issue. By mixing the infrastructure and the ad hoc modes in WLAN, we propose in this paper a new coverage improvement scheme that can identify suitable idle MSs in good service zones as traffic agents (TAs to relay traffic from those out-of-coverage MSs to the AP. The service coverage area of WLAN is then expanded. The QoS requirements (e.g., bandwidth of those MSs are considered in the selection process of corresponding TAs. Mathematical analysis, verified by computer simulations, shows that the proposed TA scheme can effectively reduce blocking probability when traffic load is light.

  20. Using latency as a QoS indicator for global cloud computing services

    DEFF Research Database (Denmark)

    Pedersen, Jens Myrup; Riaz, Tahir; Dubalski, Bozydar

    2013-01-01

    Many globally distributed cloud computing (CC) applications and services running over the Internet, between globally dispersed clients and servers, will require certain levels of QoS in order to deliver and give a sufficiently smooth user experience. This would be essential for real-time streaming...

  1. Learning-Based QoS Control Algorithms for Next Generation Internet of Things

    Directory of Open Access Journals (Sweden)

    Sungwook Kim

    2015-01-01

    Full Text Available The Internet has become an evolving entity, growing in importance and creating new value through its expansion and added utilization. The Internet of Things (IoT is a new concept associated with the future Internet and has recently become popular in a dynamic and global network infrastructure. However, in an IoT implementation, it is difficult to satisfy different Quality of Service (QoS requirements and achieve rapid service composition and deployment. In this paper, we propose a new QoS control scheme for IoT systems. Based on the Markov game model, the proposed scheme can effectively allocate IoT resources while maximizing system performance. In multiagent environments, a game theory approach can provide an effective decision-making framework for resource allocation problems. To verify the results of our study, we perform a simulation and confirm that the proposed scheme can achieve considerably improved system performance compared to existing schemes.

  2. AN AUTOMATED END-TO-END MULTI-AGENT QOS BASED ARCHITECTURE FOR SELECTION OF GEOSPATIAL WEB SERVICES

    Directory of Open Access Journals (Sweden)

    M. Shah

    2012-07-01

    With the proliferation of web services published over the internet, multiple web services may provide similar functionality, but with different non-functional properties. Thus, Quality of Service (QoS offers a metric to differentiate the services and their service providers. In a quality-driven selection of web services, it is important to consider non-functional properties of the web service so as to satisfy the constraints or requirements of the end users. The main intent of this paper is to build an automated end-to-end multi-agent based solution to provide the best-fit web service to service requester based on QoS.

  3. Fuzzy Logic-based Intelligent Scheme for Enhancing QoS of Vertical Handover Decision in Vehicular Ad-hoc Networks

    Science.gov (United States)

    Azzali, F.; Ghazali, O.; Omar, M. H.

    2017-08-01

    The design of next generation networks in various technologies under the “Anywhere, Anytime” paradigm offers seamless connectivity across different coverage. A conventional algorithm such as RSSThreshold algorithm, that only uses the received strength signal (RSS) as a metric, will decrease handover performance regarding handover latency, delay, packet loss, and handover failure probability. Moreover, the RSS-based algorithm is only suitable for horizontal handover decision to examine the quality of service (QoS) compared to the vertical handover decision in advanced technologies. In the next generation network, vertical handover can be started based on the user’s convenience or choice rather than connectivity reasons. This study proposes a vertical handover decision algorithm that uses a Fuzzy Logic (FL) algorithm, to increase QoS performance in heterogeneous vehicular ad-hoc networks (VANET). The study uses network simulator 2.29 (NS 2.29) along with the mobility traffic network and generator to implement simulation scenarios and topologies. This helps the simulation to achieve a realistic VANET mobility scenario. The required analysis on the performance of QoS in the vertical handover can thus be conducted. The proposed Fuzzy Logic algorithm shows improvement over the conventional algorithm (RSSThreshold) in the average percentage of handover QoS whereby it achieves 20%, 21% and 13% improvement on handover latency, delay, and packet loss respectively. This is achieved through triggering a process in layer two and three that enhances the handover performance.

  4. Soporte de QoS con 802.11e para tráfico heterogéneo en ambientes MANET

    OpenAIRE

    Murazzo, María Antonia; Rodríguez, Nelson R.; Guevara, Miguel José; Scheffer, María

    2014-01-01

    Hoy en día existe una gran necesidad de mejorar la calidad de servicio (QoS) ofrecida en redes móviles Ad Hoc (Mobile Ad-Hoc Networks -MANET-) que actualmente sólo ofrecen servicio best effort. Esto posee gran impacto en las aplicaciones que se corren, las cuales generan tráficos con diferentes requerimientos de recursos de la red. El presente trabajo tiene como objetivo fundamental analizar el comportamiento de la implementación de QoS en la sub capa MAC mediante 802.11e en ambientes con trá...

  5. Impact of the codec and various QoS methods on the final quality of the transferred voice in an IP network

    International Nuclear Information System (INIS)

    Slavata, Oldřich; Holub, Jan

    2015-01-01

    This paper deals with an analysis of the relation between the codec that is used, the QoS method, and the final voice transmission quality. The Cisco 2811 router is used for adjusting QoS. VoIP client Linphone is used for adjusting the codec. The criterion for transmission quality is the MOS parameter investigated with the ITU-T P.862 PESQ and P.863 POLQA algorithms

  6. Fault-tolerant and QoS based Network Layer for Security Management

    Directory of Open Access Journals (Sweden)

    Mohamed Naceur Abdelkrim

    2013-07-01

    Full Text Available Wireless sensor networks have profound effects on many application fields like security management which need an immediate, fast and energy efficient route. In this paper, we define a fault-tolerant and QoS based network layer for security management of chemical products warehouse which can be classified as real-time and mission critical application. This application generate routine data packets and alert packets caused by unusual events which need a high reliability, short end to end delay and low packet loss rate constraints. After each node compute his hop count and build his neighbors table in the initialization phase, packets can be routed to the sink. We use FELGossiping protocol for routine data packets and node-disjoint multipath routing protocol for alert packets. Furthermore, we utilize the information gathering phase of FELGossiping to update the neighbors table and detect the failed nodes, and we adapt the network topology changes by rerun the initialization phase when chemical units were added or removed from the warehouse. Analysis shows that the network layer is energy efficient and can meet the QoS constraints of unusual events packets.

  7. A QoS Optimization Approach in Cognitive Body Area Networks for Healthcare Applications.

    Science.gov (United States)

    Ahmed, Tauseef; Le Moullec, Yannick

    2017-04-06

    Wireless body area networks are increasingly featuring cognitive capabilities. This work deals with the emerging concept of cognitive body area networks. In particular, the paper addresses two important issues, namely spectrum sharing and interferences. We propose methods for channel and power allocation. The former builds upon a reinforcement learning mechanism, whereas the latter is based on convex optimization. Furthermore, we also propose a mathematical channel model for off-body communication links in line with the IEEE 802.15.6 standard. Simulation results for a nursing home scenario show that the proposed approach yields the best performance in terms of throughput and QoS for dynamic environments. For example, in a highly demanding scenario our approach can provide throughput up to 7 Mbps, while giving an average of 97.2% of time QoS satisfaction in terms of throughput. Simulation results also show that the power optimization algorithm enables reducing transmission power by approximately 4.5 dBm, thereby sensibly and significantly reducing interference.

  8. A CONTEXT AWARE BASED PRE-HANDOFF SUPPORT APPROACH TO PROVIDE OPTIMAL QOS FOR STREAMING APPLICATIONS OVER VEHICULAR AD HOC NETWORKS – HOSA

    Directory of Open Access Journals (Sweden)

    K. RAMESH BABU

    2015-06-01

    Full Text Available Large variations in network Quality of Service (QoS such as bandwidth, latency, jitter, and reliability may occur during media transfer over vehicular ad hoc networks (VANET. Usage of VANET over mobile and wireless computing applications experience “bursty” QoS behavior during the execution over distributed network scenarios. Applications such as streaming media services need to adapt their functionalities to any change in network status. Moreover, an enhanced software platform is necessary to provide adaptive network management services to upper software components. HOSA, a handoff service broker based architecture for QoS adaptation over VANET supports in providing awareness. HOSA is structured as a middleware platform both to provide QoS awareness to streaming applications as well to manage dynamic ad hoc network resources with support over handoff in an adaptive fashion. HOSA is well analyzed over routing schemes such as TIBSCRPH, SIP and ABSRP where performance of HOSA was measured using throughput, traffic intensity and end to end delay. HOSA has been analyzed using JXTA development toolkit over C++ implemented classes to demonstrate its performance over varying node mobility established using vehicular mobility based conference application.

  9. ATM QoS Experiments Using TCP Applications: Performance of TCP/IP Over ATM in a Variety of Errored Links

    Science.gov (United States)

    Frantz, Brian D.; Ivancic, William D.

    2001-01-01

    Asynchronous Transfer Mode (ATM) Quality of Service (QoS) experiments using the Transmission Control Protocol/Internet Protocol (TCP/IP) were performed for various link delays. The link delay was set to emulate a Wide Area Network (WAN) and a Satellite Link. The purpose of these experiments was to evaluate the ATM QoS requirements for applications that utilize advance TCP/IP protocols implemented with large windows and Selective ACKnowledgements (SACK). The effects of cell error, cell loss, and random bit errors on throughput were reported. The detailed test plan and test results are presented herein.

  10. Calidad de servicio (QoS en procesos: Escenarios de procesamiento con aspectos

    Directory of Open Access Journals (Sweden)

    Hector Manuel Soto Pérez

    2016-12-01

    En resumen el presente trabajo estudia conceptos básicos de calidad de servicio y algunos de sus marcos de aplicación siguiendo un enfoque aspectual. Planteando posibles casos de uso genéricos para aplicar mejoras en la prestación de la QoS mediante aspectos en la planificación y gestión de recursos de aplicaciones tradicionales.

  11. ANALISIS QOS PADA PEMBAGIAN BANDWIDTH DENGAN METODE LAYER 7 PROTOCOL, PCQ, HTB DAN HOTSPOT DI SMK SWASTA AL-WASHLIYAH PASAR SENEN

    Directory of Open Access Journals (Sweden)

    Dian Kurnia

    2017-07-01

    Full Text Available Pada penelitian ini akan dilakukan analisis QoS Pada Pembagian Bandwidth menggunakan metode HTB (Hierarchical Tocken Bucket, PCQ(Per Connection Queue  dengan Layer 7 protocol sebagai limit file berekstensi, PCQ dan Hotspot. Pada HTB menggunakan teknik antrian queue tree, PCQ dengan Layer 7 protocol, PCQ menggunakan teknik antrian simple queue, hotspot menggunakan teknik antrian simple queue. Sehingga didapat perbandingan dari metode HTB (Hierarchical Tocken Bucket, PCQ dengan Layer 7 protocol, PCQ dan hotspot akan diterapkan pada mikrotik RB750GL. Hasil akhir penelitian ini diukur dengan parameter-parameter QoS throughput, delay (latency, jitter (variasi kedatangan paket, Packet loss. Adapun hasil pengujian dalam penelitian ini dilakukan pada trafik jam sibuk untuk mengetahui sejauh mana kinerja performansi management bandwidth dengan metode-metode tersebut. Dari hasil penelitian untuk performance QoS yang lebih baik untuk memanagement bandwidth di dapat nilai throughput, jitter dan delay terbaik yaitu menggunakan metode HTB.

  12. End to End Inter-domain Quality of Service Provisioning

    DEFF Research Database (Denmark)

    Brewka, Lukasz Jerzy

    This thesis addresses selected topics of Quality of Service (QoS) provisioning in heterogeneous data networks that construct the communication environment of today's Internet. In the vast range of protocols available in different domains of network infrastructures, a few chosen ones are discussed......, the general UPnPQoS performance was assessed analytically and confirmed by simulations results. The results validate the usability of UPnP-QoS, but some open issues in the specication were identified. As a result of addressing mentioned shortcomings of UPnP-QoS, a few pre-emption algorithms for home gateway...... and discuss also access Passive Optical Network (PON) technologies, a GMPLS controlled Ten Gigabit Passive Optical Network (XGPON) was proposed. This part of the thesis introduces the possibility of managing the XG-PON by the GMPLS suite, showing again that this protocol suite is a good candidate...

  13. Seamless interworking architecture for WBAN in heterogeneous wireless networks with QoS guarantees.

    Science.gov (United States)

    Khan, Pervez; Ullah, Niamat; Ullah, Sana; Kwak, Kyung Sup

    2011-10-01

    The IEEE 802.15.6 standard is a communication standard optimized for low-power and short-range in-body/on-body nodes to serve a variety of medical, consumer electronics and entertainment applications. Providing high mobility with guaranteed Quality of Service (QoS) to a WBAN user in heterogeneous wireless networks is a challenging task. A WBAN uses a Personal Digital Assistant (PDA) to gather data from body sensors and forwards it to a remote server through wide range wireless networks. In this paper, we present a coexistence study of WBAN with Wireless Local Area Networks (WLAN) and Wireless Wide Area Networks (WWANs). The main issue is interworking of WBAN in heterogenous wireless networks including seamless handover, QoS, emergency services, cooperation and security. We propose a Seamless Interworking Architecture (SIA) for WBAN in heterogenous wireless networks based on a cost function. The cost function is based on power consumption and data throughput costs. Our simulation results show that the proposed scheme outperforms typical approaches in terms of throughput, delay and packet loss rate.

  14. Trust-Enhanced Cloud Service Selection Model Based on QoS Analysis.

    Science.gov (United States)

    Pan, Yuchen; Ding, Shuai; Fan, Wenjuan; Li, Jing; Yang, Shanlin

    2015-01-01

    Cloud computing technology plays a very important role in many areas, such as in the construction and development of the smart city. Meanwhile, numerous cloud services appear on the cloud-based platform. Therefore how to how to select trustworthy cloud services remains a significant problem in such platforms, and extensively investigated owing to the ever-growing needs of users. However, trust relationship in social network has not been taken into account in existing methods of cloud service selection and recommendation. In this paper, we propose a cloud service selection model based on the trust-enhanced similarity. Firstly, the direct, indirect, and hybrid trust degrees are measured based on the interaction frequencies among users. Secondly, we estimate the overall similarity by combining the experience usability measured based on Jaccard's Coefficient and the numerical distance computed by Pearson Correlation Coefficient. Then through using the trust degree to modify the basic similarity, we obtain a trust-enhanced similarity. Finally, we utilize the trust-enhanced similarity to find similar trusted neighbors and predict the missing QoS values as the basis of cloud service selection and recommendation. The experimental results show that our approach is able to obtain optimal results via adjusting parameters and exhibits high effectiveness. The cloud services ranking by our model also have better QoS properties than other methods in the comparison experiments.

  15. Efficient Resources Provisioning Based on Load Forecasting in Cloud

    Directory of Open Access Journals (Sweden)

    Rongdong Hu

    2014-01-01

    Full Text Available Cloud providers should ensure QoS while maximizing resources utilization. One optimal strategy is to timely allocate resources in a fine-grained mode according to application’s actual resources demand. The necessary precondition of this strategy is obtaining future load information in advance. We propose a multi-step-ahead load forecasting method, KSwSVR, based on statistical learning theory which is suitable for the complex and dynamic characteristics of the cloud computing environment. It integrates an improved support vector regression algorithm and Kalman smoother. Public trace data taken from multitypes of resources were used to verify its prediction accuracy, stability, and adaptability, comparing with AR, BPNN, and standard SVR. Subsequently, based on the predicted results, a simple and efficient strategy is proposed for resource provisioning. CPU allocation experiment indicated it can effectively reduce resources consumption while meeting service level agreements requirements.

  16. An Improved MOEA/D for QoS Oriented Multimedia Multicasting with Network Coding

    Directory of Open Access Journals (Sweden)

    Zhaoyuan Wang

    2015-08-01

    Full Text Available Recent years witness a significant growth in multimedia applications. Among them, a stream of applications is real-time and requires one-to-many fast data transmission with stringent quality-of-service (QoS requirements, where multicast is an important supporting technology. In particular, with more and more mobile end users requesting real-time broadband multimedia applications, it is of vital importance to provide them with satisfied quality of experience. As network coding can offer higher bandwidth to users and accommodate more flows for networks than traditional routing, this paper studies the multicast routing problem with network coding and formulates it as a multi-objective optimization problem. As delay and packet loss ratio (PLR are two important performance indicators for QoS, we consider them as the two objectives for minimization. To address the problem above, we present a multi-objective evolutionary algorithm based on decomposition (MOEA/D, where an all population updating rule is devised to address the problem of lacking feasible solutions in the search space. Experimental results demonstrate the effectiveness of the proposed algorithm and it outperforms a number of state-of-the-art algorithms.

  17. QoS Modeling for End-to-End Performance Evaluation over Networks with Wireless Access

    Directory of Open Access Journals (Sweden)

    Gómez Gerardo

    2010-01-01

    Full Text Available This paper presents an end-to-end Quality of Service (QoS model for assessing the performance of data services over networks with wireless access. The proposed model deals with performance degradation across protocol layers using a bottom-up strategy, starting with the physical layer and moving on up to the application layer. This approach makes it possible to analytically assess performance at different layers, thereby facilitating a possible end-to-end optimization process. As a representative case, a scenario where a set of mobile terminals connected to a streaming server through an IP access node has been studied. UDP, TCP, and the new TCP-Friendly Rate Control (TFRC protocols were analyzed at the transport layer. The radio interface consisted of a variable-rate multiuser and multichannel subsystem, including retransmissions and adaptive modulation and coding. The proposed analytical QoS model was validated on a real-time emulator of an end-to-end network with wireless access and proved to be very useful for the purposes of service performance estimation and optimization.

  18. QoS modelling and analysis with UML-statecharts: the StoCharts approach

    OpenAIRE

    Jansen, D.N.; Haverkort, Boudewijn R.H.M.; Hermanns, H.; Katoen, Joost P.

    2005-01-01

    The UML is an influential and widespread notation for high-level modelling of information processing systems. UML statechart diagrams are a graphical language to describe system behaviour. They consitute one of the most intensively-used formalisms comprised by the UML. However, statechart diagrams are lacking concepts for describing real-time, performance, dependability and quality of service (QoS) characteristics at a behavioural level.This note describes a QoS-oriented extension of UML stat...

  19. QoS Management and Control for an All-IP WiMAX Network Architecture: Design, Implementation and Evaluation

    Directory of Open Access Journals (Sweden)

    Thomas Michael Bohnert

    2008-01-01

    Full Text Available The IEEE 802.16 standard provides a specification for a fixed and mobile broadband wireless access system, offering high data rate transmission of multimedia services with different Quality-of-Service (QoS requirements through the air interface. The WiMAX Forum, going beyond the air interface, defined an end-to-end WiMAX network architecture, based on an all-IP platform in order to complete the standards required for a commercial rollout of WiMAX as broadband wireless access solution. As the WiMAX network architecture is only a functional specification, this paper focuses on an innovative solution for an end-to-end WiMAX network architecture offering in compliance with the WiMAX Forum specification. To our best knowledge, this is the first WiMAX architecture built by a research consortium globally and was performed within the framework of the European IST project WEIRD (WiMAX Extension to Isolated Research Data networks. One of the principal features of our architecture is support for end-to-end QoS achieved by the integration of resource control in the WiMAX wireless link and the resource management in the wired domains in the network core. In this paper we present the architectural design of these QoS features in the overall WiMAX all-IP framework and their functional as well as performance evaluation. The presented results can safely be considered as unique and timely for any WiMAX system integrator.

  20. Dynamic QoS management in Differentiated Services using bandwidth brokers, RSVP aggregation and load control protocols

    NARCIS (Netherlands)

    Westberg, Lars; Eriksson, Anders; Karagiannis, Georgios; Heijenk, Geert; Rexhepi, Vlora; Partain, David

    2001-01-01

    A method and network subsystem for providing on demand end to end Quality of Service (Qos) in a dynamic manner, use a combination of Resource Reservation Protocol (RSVP), load control protocol (and its successors) and Bandwidth Brokers (BBs)(1106) which communicate using a predetermined protocol.

  1. Dynamic QoS management in Differentiated Services using bandwidth brokers, RSVP aggregation and load control protocols

    NARCIS (Netherlands)

    Westberg, Lars; Eriksson, Anders; Karagiannis, Georgios; Heijenk, Geert; Rexhepi, Vlora; Partain, David

    2009-01-01

    A method and network subsystem for providing on demand end to end Quality of Service (Qos) in a dynamic manner, use a combination of Resource Reservation Protocol (RSVP), load control protocol (and its successors) and Bandwidth Brokers (BBs)(1106) which communicate using a predetermined protocol.

  2. Model checking and evaluating QoS of batteries in MPSoC dataflow applications via hybrid automata

    NARCIS (Netherlands)

    Ahmad, W.; Jongerden, M.R.; Stoelinga, Mariëlle Ida Antoinette; van de Pol, Jan Cornelis

    2016-01-01

    System lifetime is a major design constraint for battery-powered mobile embedded systems. The increasing gap between the energy demand of portable devices and their battery capacities is further limiting durability of mobile devices. Thus, the guarantees over Quality of Service (QoS) of

  3. An Approach for Quality of Service Management

    National Research Council Canada - National Science Library

    Lee, Chen

    1998-01-01

    ... (in terms of customizable and expressiveness) QoS specification interface for multi-dimensional QoS provisioning, a quality-of service index model to help the user make the quality trade-off decision, and a unified QoS-based admission control...

  4. Evaluasi Kinerja IEEE 802.11e HCCA untuk Dukungan QoS pada WLAN Menggunakan NS-2

    Directory of Open Access Journals (Sweden)

    Amry Daulat Gultom

    2014-06-01

    Full Text Available Wireless Local Area Network (WLAN digunakan oleh trafik multimedia yang seharusnya memerlukan persyaratan jaringan yang lebih baik terhadap delay, jitter dan packet losses. IEEE 802.11 Task Group E memperkenalkan perbaikan protokol MAC 802.11, yaitu Hybrid Coordination Function (HCF, yang terdiri dari dua mekanisme akses: Enhanced Distributed Channel Access (EDCA dan HCF Controlled Channel Access (HCCA yang memberikan dukungan Kualitas Layanan/Quality of Service (QoS bagi trafik multimedia. Tujuan dari penelitian ini adalah untuk memahami algoritma protokol MAC IEEE 802.11e HCCA pada jaringan WLAN, dan menganalisis kinerja protokol MAC 802.11e HCCA pada aplikasi multimedia dengan menggunakan metode simulasi pada NS-2. Metrik kinerja yang diukur adalah jitter dan throughput-nya. Hasil penelitian ini menunjukkan bahwa protokol MAC HCCA dapat memberikan jaminan QoS dibanding protokol MAC DCF, dimana jitter HCCA lebih stabil dari pada jitter DCF. Begitupula dengan throughput HCCA yang tidak berubah selama trafik berlangsung, tidak seperti pada DCF yang masih mengalami fluktuasi yang besar.

  5. Designing area optimized application-specific network-on-chip architectures while providing hard QoS guarantees.

    Directory of Open Access Journals (Sweden)

    Sajid Gul Khawaja

    Full Text Available With the increase of transistors' density, popularity of System on Chip (SoC has increased exponentially. As a communication module for SoC, Network on Chip (NoC framework has been adapted as its backbone. In this paper, we propose a methodology for designing area-optimized application specific NoC while providing hard Quality of Service (QoS guarantees for real time flows. The novelty of the proposed system lies in derivation of a Mixed Integer Linear Programming model which is then used to generate a resource optimal Network on Chip (NoC topology and architecture while considering traffic and QoS requirements. We also present the micro-architectural design features used for enabling traffic and latency guarantees and discuss how the solution adapts for dynamic variations in the application traffic. The paper highlights the effectiveness of proposed method by generating resource efficient NoC solutions for both industrial and benchmark applications. The area-optimized results are generated in few seconds by proposed technique, without resorting to heuristics, even for an application with 48 traffic flows.

  6. Study of QoS control and reliable routing method for utility communication network. Application of differentiated service to the network and alternative route establishment by the IP routing protocol; Denryokuyo IP network no QoS seigyo to shinraisei kakuho no hoho. DiffServ ni yoru QoS seigyo no koka to IP ni yoru fuku root ka no kento

    Energy Technology Data Exchange (ETDEWEB)

    Oba, E.

    2000-05-01

    QoS control method which satisfies utilities communication network requirement and alternative route establishment method which is for sustaining communication during a failure are studied. Applicability of DiffServ (Differentiated Service), one of the most promising QoS control method on IP network and studying energetically in IETF WG, is studied and it is found most application used in the utility communication network except for relaying system information could he accommodated to the DiffServ network. An example of the napping of the utility communication applications to the DiffServ PHB (Per Hop Behavior) is shown in this paper. Regarding to the alternative route, usual IP routing protocol cannot establish alternative route which doesn't have common links and nodes in their paths for a destination. IP address duplication with some modification of routing protocol enables such alternative route establishment. MPLS, distance vector algorithm and link state algorithm are evaluated qualitatively, and as a result, we found MPLS is promising way to establish the route. Quantitative evaluation will be future work. (author)

  7. Joint terminals and relay optimization for two-way power line information exchange systems with QoS constraints

    Science.gov (United States)

    Wu, Xiaolin; Rong, Yue

    2015-12-01

    The quality-of-service (QoS) criteria (measured in terms of the minimum capacity requirement in this paper) are very important to practical indoor power line communication (PLC) applications as they greatly affect the user experience. With a two-way multicarrier relay configuration, in this paper we investigate the joint terminals and relay power optimization for the indoor broadband PLC environment, where the relay node works in the amplify-and-forward (AF) mode. As the QoS-constrained power allocation problem is highly non-convex, the globally optimal solution is computationally intractable to obtain. To overcome this challenge, we propose an alternating optimization (AO) method to decompose this problem into three convex/quasi-convex sub-problems. Simulation results demonstrate the fast convergence of the proposed algorithm under practical PLC channel conditions. Compared with the conventional bidirectional direct transmission (BDT) system, the relay-assisted two-way information exchange (R2WX) scheme can meet the same QoS requirement with less total power consumption.

  8. Semantic Network Adaptation Based on QoS Pattern Recognition for Multimedia Streams

    Science.gov (United States)

    Exposito, Ernesto; Gineste, Mathieu; Lamolle, Myriam; Gomez, Jorge

    This article proposes an ontology based pattern recognition methodology to compute and represent common QoS properties of the Application Data Units (ADU) of multimedia streams. The use of this ontology by mechanisms located at different layers of the communication architecture will allow implementing fine per-packet self-optimization of communication services regarding the actual application requirements. A case study showing how this methodology is used by error control mechanisms in the context of wireless networks is presented in order to demonstrate the feasibility and advantages of this approach.

  9. Software Defined Networking

    DEFF Research Database (Denmark)

    Caba, Cosmin Marius

    Network Service Providers (NSP) often choose to overprovision their networks instead of deploying proper Quality of Services (QoS) mechanisms that allow for traffic differentiation and predictable quality. This tendency of overprovisioning is not sustainable for the simple reason that network...... resources are limited. Hence, to counteract this trend, current QoS mechanisms must become simpler to deploy and operate, in order to motivate NSPs to employ QoS techniques instead of overprovisioning. Software Defined Networking (SDN) represents a paradigm shift in the way telecommunication and data...... generic perspective (e.g. service provisioning speed, resources availability). As a result, new mechanisms for providing QoS are proposed, solutions for SDN-specific QoS challenges are designed and tested, and new network management concepts are prototyped, all aiming to improve QoS for network services...

  10. QoS Supported IPTV Service Architecture over Hybrid-Tree-Based Explicit Routed Multicast Network

    Directory of Open Access Journals (Sweden)

    Chih-Chao Wen

    2012-01-01

    Full Text Available With the rapid advance in multimedia streaming and multicast transport technology, current IP multicast protocols, especially PIM-SM, become the major channel delivery mechanism for IPTV system over Internet. The goals for IPTV service are to provide two-way interactive services for viewers to select popular program channel with high quality for watching during fast channel surfing period. However, existing IP multicast protocol cannot meet above QoS requirements for IPTV applications between media server and subscribers. Therefore, we propose a cooperative scheme of hybrid-tree based on explicit routed multicast, called as HT-ERM to combine the advantages of shared tree and source tree for QoS-supported IPTV service. To increase network utilization, the constrained shortest path first (CSPF routing algorithm is designed for construction of hybrid tree to deliver the high-quality video stream over watching channel and standard quality over surfing channel. Furthermore, the Resource Reservation Protocol- Traffic Engineering (RSVP-TE is used as signaling mechanism to set up QoS path for multicast channel admission control. Our simulation results demonstrated that the proposed HT-ERM scheme outperforms other multicast QoS-based delivery scheme in terms of channel switching delay, resource utilization, and blocking ratio for IPTV service.

  11. Leveraging 802.11n frame aggregation to enhance QoS and power consumption in Wi-Fi networks

    NARCIS (Netherlands)

    Camps-Mur, D.; Gomony, M.D.; Perez-Costa, X.; Sallent-Ribes, S.

    2012-01-01

    The Wi-Fi technology, driven by its tremendous success, is expanding into a wide variety of devices and applications. However, many of these new devices, like handheld devices, pose new challenges in terms of QoS and energy efficiency. In order to address these challenges, in this paper we study how

  12. Upper Bound for Queue length in Regulated Burst Service Scheduling

    Directory of Open Access Journals (Sweden)

    Mahmood Daneshvar Farzanegan

    2016-01-01

    Full Text Available Quality of Service (QoS provisioning is very important in next computer/communication networks because of increasing multimedia services. Hence, very investigations are performed in this area. Scheduling algorithms effect QoS provisioning. Lately, a scheduling algorithm called Regulated Burst Service Scheduling (RBSS suggested by author in [1] to provide a better service to bursty and delay sensitive services such as video. One of the most significant feature in RBSS is considering burstiness of arrival traffic in scheduling algorithm. In this paper, an upper bound of queue length or buffer size and service curve are calculated by Network Calculus analysis for RBSS. Because in RBSS queue length is a parameter that is considered in scheduling arbitrator, analysis results a differential inequality to obtain service curve. To simplify, arrival traffic is assumed to be linear that is defined in the paper clearly. This paper help to analysis delay in RBSS for different traffic with different specifications. Therefore, QoS provisioning will be evaluated.

  13. Cost of provision of opioid substitution therapy provision in Tijuana, Mexico.

    Science.gov (United States)

    Burgos, Jose Luis; Cepeda, Javier A; Kahn, James G; Mittal, Maria Luisa; Meza, Emilio; Lazos, Raúl Rafael Palacios; Vargas, Psyché Calderón; Vickerman, Peter; Strathdee, Steffanie A; Martin, Natasha K

    2018-05-23

    Mexico recently enacted drug policy reform to decriminalize possession of small amounts of illicit drugs and mandated that police refer identified substance users to drug treatment. However, the economic implications of drug treatment expansion are uncertain. We estimated the costs of opioid substitution therapy (OST) provision in Tijuana, Mexico, where opioid use and HIV are major public health concerns. We adopted an economic health care provider perspective and applied an ingredients-based micro-costing approach to quantify the average monthly cost of OST (methadone maintenance) provision at two providers (one private and one public) in Tijuana, Mexico. Costs were divided by type of input (capital, recurrent personnel and non-personnel). We defined "delivery cost" as all costs except for the methadone and compared total cost by type of methadone (powdered form or capsule). Cost data were obtained from interviews with senior staff and review of expenditure reports. Service provision data were obtained from activity logs and senior staff interviews. Outcomes were cost per OST contact and cost per person month of OST. We additionally collected information on patient charges for OST provision from published rates. The total cost per OST contact at the private and public sites was $3.12 and $5.90, respectively, corresponding to $95 and $179 per person month of OST. The costs of methadone delivery per OST contact were similar at both sites ($2.78 private and $3.46 public). However, cost of the methadone itself varied substantially ($0.34 per 80 mg dose [powder] at the private site and $2.44 per dose [capsule] at the public site). Patients were charged $1.93-$2.66 per methadone dose. The cost of OST provision in Mexico is consistent with other upper-middle income settings. However, evidenced-based (OST) drug treatment facilities in Mexico are still unaffordable to most people who inject drugs.

  14. QoS Parameters Evaluation in a VPN-MPLS Diffserv Network under a Complete Free Software Emulation Environment

    Directory of Open Access Journals (Sweden)

    Miroslava Aracely Zapata Rodríguez

    2017-12-01

    Full Text Available The use of Virtual Private Network – Multi Protocol Label Switching (VPN-MPLS networks has become very common inside enterprises thanks to their multiple advantages; such as, the private communication across a public network infrastructure between geographically diverse sites. This leads to a need for an efficient network in terms of Quality of Service (QoS to guarantee reliability and security of information. However, the implementation of a VPN-MPLS network is neither easy nor cheap for small and medium companies; hence, in most cases, it is required the use of emulators that are not free either. In this paper, we analyze a VPN-MPLS network in terms of QoS metrics: delay, jitter and packet loss. This evaluation was performed in a virtual environment using only free software tools under two test scenarios, with and without Differentiated Services (DiffServ. The results showed that a VPN-MPLS DiffServ network reduces the delay by approximately 96.78% in VoIP, 39.21% in Data and 66.83% in Streaming; furthermore, the jitter was reduced by approximately 27.88% in VoIP and 41.09% in Data.

  15. iQOS: evidence of pyrolysis and release of a toxicant from plastic.

    Science.gov (United States)

    Davis, Barbara; Williams, Monique; Talbot, Prue

    2018-03-13

    To evaluate performance of the I quit original smoking (iQOS) heat-not-burn system as a function of cleaning and puffing topography, investigate the validity of manufacturer's claims that this device does not burn tobacco and determine if the polymer-film filter is potentially harmful. iQOS performance was evaluated using five running conditions incorporating two different cleaning protocols. Heatsticks were visually and stereomicroscopically inspected preuse and postuse to determine the extent of tobacco plug charring (from pyrolysis) and polymer-film filter melting, and to elucidate the effects of cleaning on charring. Gas chromatography-mass spectrometry headspace analysis was conducted on unused polymer-film filters to determine if potentially toxic chemicals are emitted from the filter during heating. For all testing protocols, pressure drop decreased as puff number increased. Changes in testing protocols did not affect aerosol density. Charring due to pyrolysis (a form of organic matter thermochemical decomposition) was observed in the tobacco plug after use. When the manufacturer's cleaning instructions were followed, both charring of the tobacco plug and melting of the polymer-film filter increased. Headspace analysis of the polymer-film filter revealed the release of formaldehyde cyanohydrin at 90°C, which is well below the maximum temperature reached during normal usage. Device usage limitations may contribute to decreases in interpuff intervals, potentially increasing user's intake of nicotine and other harmful chemicals. This study found that the tobacco plug does char and that charring increases when the device is not cleaned between heatsticks. Release of formaldehyde cyanohydrin is a concern as it is highly toxic at very low concentrations. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  16. Performance Analysis of Quality-of-Service Controls in a Cell-Cluster-Based Wireless ATM Network

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Young Jong [Ajou University, Suwon (Korea, Republic of)

    1997-04-01

    In this paper, an efficient cell-cluster-based call control scheme with guaranteed quality-of-service(QoS) provision ing is presented for next generation wireless ATM networks and its performance is mathematically analyzed using the open queuing network. With the cell-cluster-based call control, at the time a mobile connection is admitted to the network, a virtual cell is constructed by choosing a group of neighboring base stations to which the call may probabilistic ally hand over and by assigning to the call a collection of virtual paths between the base stations. Within a micro cell/pico cell environment, it is seen that the cell-cluster-based call control can support effectively a very high rate of handovers, provides very high system capacity, and guarantees a high degree of frequency reuse over the same geographical region without requiring the intervention of the network call control processor each time a handover occurs. But since mobiles, once admitted, are free to roam within the virtual cell, congestion condition occurs in which the number of calls to be handled by one base station exceeds the cell sites` capacity of radio channel and consequently a predefined QoS provision cannot be guaranteed. So, there must be a call admission control function to limit the number of calls existing in a cell-cluster such that required QoS objectives are met. As call acceptance criteria for constant-bit-rate or realtime variable-bit-rate ATM connections, we define four mobile QoS metrics: new-call blocking probability, wireless channel utilization efficiency, congestion probability and normalized average congestion duration. In addition, for QoS provision ing to available-bit-rate, unspecified-bit-rate or non-realtime variable-bit-rate connections, we further define another QoS metric, the minimum threshold breaking probability. By using the open network queuing model, we derive closed form expressions for the five QoS metrics defined above and show that they can be

  17. Narrowing the Gap Between QoS Metrics and Web QoE Using Above-the-fold Metrics

    OpenAIRE

    da Hora, Diego Neves; Asrese, Alemnew; Christophides, Vassilis; Teixeira, Renata; Rossi, Dario

    2018-01-01

    International audience; Page load time (PLT) is still the most common application Quality of Service (QoS) metric to estimate the Quality of Experience (QoE) of Web users. Yet, recent literature abounds with proposals for alternative metrics (e.g., Above The Fold, SpeedIndex and variants) that aim at better estimating user QoE. The main purpose of this work is thus to thoroughly investigate a mapping between established and recently proposed objective metrics and user QoE. We obtain ground tr...

  18. An Automated End-To Multi-Agent Qos Based Architecture for Selection of Geospatial Web Services

    Science.gov (United States)

    Shah, M.; Verma, Y.; Nandakumar, R.

    2012-07-01

    Over the past decade, Service-Oriented Architecture (SOA) and Web services have gained wide popularity and acceptance from researchers and industries all over the world. SOA makes it easy to build business applications with common services, and it provides like: reduced integration expense, better asset reuse, higher business agility, and reduction of business risk. Building of framework for acquiring useful geospatial information for potential users is a crucial problem faced by the GIS domain. Geospatial Web services solve this problem. With the help of web service technology, geospatial web services can provide useful geospatial information to potential users in a better way than traditional geographic information system (GIS). A geospatial Web service is a modular application designed to enable the discovery, access, and chaining of geospatial information and services across the web that are often both computation and data-intensive that involve diverse sources of data and complex processing functions. With the proliferation of web services published over the internet, multiple web services may provide similar functionality, but with different non-functional properties. Thus, Quality of Service (QoS) offers a metric to differentiate the services and their service providers. In a quality-driven selection of web services, it is important to consider non-functional properties of the web service so as to satisfy the constraints or requirements of the end users. The main intent of this paper is to build an automated end-to-end multi-agent based solution to provide the best-fit web service to service requester based on QoS.

  19. OPTIMISATION OF BUFFER SIZE FOR ENHANCING QOS OF VIDEO TRAFFIC USING CROSS LAYERED HYBRID TRANSPORT LAYER PROTOCOL APPROACH

    OpenAIRE

    S. Matilda; B. Palaniappan

    2011-01-01

    Video streaming is gaining importance, with the wide popularity of multimedia rich applications in the Internet. Video streams are delay sensitive and require seamless flow for continuous visualization. Properly designed buffers offer a solution to queuing delay. The diagonally opposite QoS metrics associated with video traffic poses an optimization problem, in the design of buffers. This paper is a continuation of our previous work [1] and deals with the design of buffers. It aims at finding...

  20. Two-dimensional priority-based dynamic resource allocation algorithm for QoS in WDM/TDM PON networks

    Science.gov (United States)

    Sun, Yixin; Liu, Bo; Zhang, Lijia; Xin, Xiangjun; Zhang, Qi; Rao, Lan

    2018-01-01

    Wavelength division multiplexing/time division multiplexing (WDM/TDM) passive optical networks (PON) is being viewed as a promising solution for delivering multiple services and applications. The hybrid WDM / TDM PON uses the wavelength and bandwidth allocation strategy to control the distribution of the wavelength channels in the uplink direction, so that it can ensure the high bandwidth requirements of multiple Optical Network Units (ONUs) while improving the wavelength resource utilization. Through the investigation of the presented dynamic bandwidth allocation algorithms, these algorithms can't satisfy the requirements of different levels of service very well while adapting to the structural characteristics of mixed WDM / TDM PON system. This paper introduces a novel wavelength and bandwidth allocation algorithm to efficiently utilize the bandwidth and support QoS (Quality of Service) guarantees in WDM/TDM PON. Two priority based polling subcycles are introduced in order to increase system efficiency and improve system performance. The fixed priority polling subcycle and dynamic priority polling subcycle follow different principles to implement wavelength and bandwidth allocation according to the priority of different levels of service. A simulation was conducted to study the performance of the priority based polling in dynamic resource allocation algorithm in WDM/TDM PON. The results show that the performance of delay-sensitive services is greatly improved without degrading QoS guarantees for other services. Compared with the traditional dynamic bandwidth allocation algorithms, this algorithm can meet bandwidth needs of different priority traffic class, achieve low loss rate performance, and ensure real-time of high priority traffic class in terms of overall traffic on the network.

  1. 5G Terminals with Multi-Streaming Features for Real-Time Mobile Broadband Applications

    Directory of Open Access Journals (Sweden)

    T. Shuminoski

    2017-06-01

    Full Text Available In this paper we present a novel QoS framework on the network layer for 5G terminals with vertical multi-homing and multi-streaming capabilities by using radio networks aggregation. The proposed framework is leading to high performance utility networks with QoS provisioning for real-time multimedia services by achieving low packet delays, stochastic queuing network stability and highest mobile broadband capabilities i.e. bitrates. The proposed QoS algorithm is implemented within the mobile terminals on one side, and in dedicated proxy servers on mobile core network side. It is based on Lyapunov optimization techniques and it is targeted to handle simultaneously multiple multimedia service flows via multiple radio network interfaces in parallel.

  2. Optimization of Task Scheduling Algorithm through QoS Parameters for Cloud Computing

    Directory of Open Access Journals (Sweden)

    Monika

    2016-01-01

    Full Text Available Cloud computing is an incipient innovation which broadly spreads among analysts. It furnishes clients with foundation, stage and programming as enhancement which is easily available by means of web. A cloud is a sort of parallel and conveyed framework comprising of a gathering of virtualized PCs that are utilized to execute various tasks to accomplish good execution time, accomplish due date and usage of its assets. The scheduling issue can be seen as the finding an ideal task of assignments over the accessible arrangement of assets with the goal that we can accomplish the wanted objectives for tasks. This paper presents an optimal algorithm for scheduling tasks to get their waiting time as a QoS parameter. The algorithm is simulated using Cloudsim simulator and experiments are carried out to help clients to make sense of the bottleneck of utilizing no. of virtual machine parallely.

  3. Efficient Job Provisioning for a Cloud Service Provider

    Directory of Open Access Journals (Sweden)

    Sharma Dharmvir

    2016-01-01

    Full Text Available Cloud Computing is a very fast emerging technology as every enterprise is moving fast towards this system. Cloud Computing is known as a provider of dynamic services. It optimizes a very large, scalable and virtualized resource. So lots of industries have joined this bandwagon nowadays. One of the major research issues is to maintain good Quality of Service (QoS of a Cloud Service Provider (CSP. The QoS encompasses different parameters, like, smart job allocation strategy, efficient load balancing, response time optimization, reduction in wastage of bandwidth, accountability of the overall system, etc. The efficient allocation strategy of the independent computational jobs among different Virtual Machines (VM in a Data center (DC is a distinguishable challenge in the Cloud Computing domain and finding out an optimal job allocation strategy guided by a good scheduling heuristic for such an environment is a mape-k loop problem. So different heuristic approaches may be used for better result and in this result we paper we implement worst fit in mape-k and evaluated the results.

  4. Risk factors for child maltreatment recurrence: An updated systematic review.

    Science.gov (United States)

    White, Oliver G; Hindley, Nick; Jones, David P H

    2015-10-01

    Children who have been maltreated are at increased risk of further maltreatment. Identification of those at highest risk of further maltreatment is a priority for professionals working in child protection services. The current study is intended to consolidate and expand on previous work on recurrence of child maltreatment. It has sought to identify risk factors for maltreatment recurrence in the recent literature in the expectation that this may help in the practical identification of children at risk. We conducted a systematic review of cohort studies published between 2003 and 2009, identifying factors associated with maltreatment recurrence in children. Studies included demonstrated differing levels of substantiation of maltreatment. Fifteen studies met inclusion criteria but showed significant heterogeneity, varying in setting, recruitment of subjects, types of maltreatment considered and length of follow-up. Previous findings were replicated and expanded in the current study in relation to a range of factors, including rates of maltreatment recurrence, maltreatment types, frequency of previous episodes of maltreatment, child and family considerations, home environment and service provision. Factors were identified irrespective of level of maltreatment substantiation. This study provides further systematic evidence of the existence of a number of factors associated with child maltreatment recurrence. It points to the possibility of practical application of its findings within the wider context of decision making in child protection services, with the ultimate aim of reducing recurrence of maltreatment in individual cases. © The Author(s) 2014.

  5. Quality of service and service provisioning on a competitive market

    NARCIS (Netherlands)

    Nieuwenhuis, Lambert J.M.; Widya, I.A.

    2000-01-01

    The objective of this paper is to provide an economic and commercial context for QoS research in open distributed environments. The analyses are based on a telecommunications value chain model. The model is used to define possible roles for telecommunications companies, migrating from traditional

  6. Quality of Service and Service Provisioning on a Competative Market

    NARCIS (Netherlands)

    Nieuwenhuis, Lambertus Johannes Maria; Linnhoff-Popien, C.; Widya, I.A.; Hegering, H.G.

    2000-01-01

    The objective of this paper is to provide an economic and commercial context for QoS research in open distributed environments. The analyses are based on a telecommunications value chain model. The model is used to define possible roles for telecommunications companies, migrating from traditional

  7. A novel PON based UMTS broadband wireless access network architecture with an algorithm to guarantee end to end QoS

    Science.gov (United States)

    Sana, Ajaz; Hussain, Shahab; Ali, Mohammed A.; Ahmed, Samir

    2007-09-01

    In this paper we proposes a novel Passive Optical Network (PON) based broadband wireless access network architecture to provide multimedia services (video telephony, video streaming, mobile TV, mobile emails etc) to mobile users. In the conventional wireless access networks, the base stations (Node B) and Radio Network Controllers (RNC) are connected by point to point T1/E1 lines (Iub interface). The T1/E1 lines are expensive and add up to operating costs. Also the resources (transceivers and T1/E1) are designed for peak hours traffic, so most of the time the dedicated resources are idle and wasted. Further more the T1/E1 lines are not capable of supporting bandwidth (BW) required by next generation wireless multimedia services proposed by High Speed Packet Access (HSPA, Rel.5) for Universal Mobile Telecommunications System (UMTS) and Evolution Data only (EV-DO) for Code Division Multiple Access 2000 (CDMA2000). The proposed PON based back haul can provide Giga bit data rates and Iub interface can be dynamically shared by Node Bs. The BW is dynamically allocated and the unused BW from lightly loaded Node Bs is assigned to heavily loaded Node Bs. We also propose a novel algorithm to provide end to end Quality of Service (QoS) (between RNC and user equipment).The algorithm provides QoS bounds in the wired domain as well as in wireless domain with compensation for wireless link errors. Because of the air interface there can be certain times when the user equipment (UE) is unable to communicate with Node B (usually referred to as link error). Since the link errors are bursty and location dependent. For a proposed approach, the scheduler at the Node B maps priorities and weights for QoS into wireless MAC. The compensations for errored links is provided by the swapping of services between the active users and the user data is divided into flows, with flows allowed to lag or lead. The algorithm guarantees (1)delay and throughput for error-free flows,(2)short term fairness

  8. Maximization of the Supportable Number of Sensors in QoS-Aware Cluster-Based Underwater Acoustic Sensor Networks

    Directory of Open Access Journals (Sweden)

    Thi-Tham Nguyen

    2014-03-01

    Full Text Available This paper proposes a practical low-complexity MAC (medium access control scheme for quality of service (QoS-aware and cluster-based underwater acoustic sensor networks (UASN, in which the provision of differentiated QoS is required. In such a network, underwater sensors (U-sensor in a cluster are divided into several classes, each of which has a different QoS requirement. The major problem considered in this paper is the maximization of the number of nodes that a cluster can accommodate while still providing the required QoS for each class in terms of the PDR (packet delivery ratio. In order to address the problem, we first estimate the packet delivery probability (PDP and use it to formulate an optimization problem to determine the optimal value of the maximum packet retransmissions for each QoS class. The custom greedy and interior-point algorithms are used to find the optimal solutions, which are verified by extensive simulations. The simulation results show that, by solving the proposed optimization problem, the supportable number of underwater sensor nodes can be maximized while satisfying the QoS requirements for each class.

  9. Recurrent varicocele

    Directory of Open Access Journals (Sweden)

    Katherine Rotker

    2016-01-01

    Full Text Available Varicocele recurrence is one of the most common complications associated with varicocele repair. A systematic review was performed to evaluate varicocele recurrence rates, anatomic causes of recurrence, and methods of management of recurrent varicoceles. The PubMed database was evaluated using keywords "recurrent" and "varicocele" as well as MESH criteria "recurrent" and "varicocele." Articles were not included that were not in English, represented single case reports, focused solely on subclinical varicocele, or focused solely on a pediatric population (age <18. Rates of recurrence vary with the technique of varicocele repair from 0% to 35%. Anatomy of recurrence can be defined by venography. Management of varicocele recurrence can be surgical or via embolization.

  10. GUEST EDITORS' INTRODUCTION: Guest Editors' introduction

    Science.gov (United States)

    Coulson, Geoff; de Meer, Jan B.

    1997-03-01

    independence, and also more recognition of QoS as an independent research area, was achieved in the above mentioned Paris workshop. This workshop was aligned with the IFIP conference on Formal Methods for Open Object-based Distributed Systems (FMOODS96), but was also independently recognised by IFIP. A fifth workshop is due to take place in May 1997 in New York. This event will be the first not to be organized under the umbrella of another big event. This is indicative of the fact that the community interested in QoS issues has now become large enough to maintain its own independent forum of discussion and exchange of expertise. The five papers in this special issue cover a wide range of QoS research issues and fall broadly into three categories. First we have a paper that addresses a very specific but nevertheless crucial aspect of QoS provision: supporting the QoS of variable bit rate (VBR) traffic in networks with deterministic guarantees. `On the effects of smoothing for deterministic QoS' by Edward Knightly and Paola Rossaro examines the impact of rate smoothing of VBR sources such as MPEG video. The impact of such smoothing on both the QoS as perceived by the user and on resource utilization in the network are considered. Experimental evidence is presented which shows quantitatively how reducing burstiness through source smoothing techniques can significantly reduce the resource utilization of VBR streams while maintaining deterministic QoS for the user (at the cost of some increase in the end-to-end delay bound). It is also shown that a richer traffic characterisation model (D-BIND) can produce better network utilization and user QoS than the usual models based only on peak rate, average rate and burst length. Next we have two papers concerned with broader issues of QoS management. These papers explore approaches to QoS monitoring and adaptation which are intended to be generic and applicable in a range of implementation environments. `Some principles for quality of

  11. Retrospective evaluation of recurrent secondary septic peritonitis in dogs (2000-2011): 41 cases.

    Science.gov (United States)

    Barfield, Dominic M; Tivers, Michael S; Holahan, Matthew; Welch, Kristin; House, Arthur; Adamantos, Sophie E

    2016-01-01

    To describe the clinical characteristics of recurrent septic peritonitis in dogs. Multicenter retrospective observational study. Client-owned dogs with recurrent septic peritonitis. Three university emergency and referral hospitals. None. Medical records from 3 veterinary university teaching hospitals were reviewed and data were collected using a standardized data collection sheet for all cases of septic peritonitis during the study period (2000-2011). Forty one dogs met the inclusion criteria for recurrent peritonitis. All dogs underwent relaparotomy. The original cause of septic peritonitis in these cases included previous surgery for gastrointestinal foreign body removal (n = 26), gastrointestinal neoplasia (n = 3), gastric or duodenal ulceration (n = 3), biliary tract leakage (n = 2), and single instance for each of the following: penetrating foreign body, hernia strangulation, intussusception, mesenteric volvulus, infection of the laparotomy incision, prostatic abscess, and trauma. Eighteen animals survived to discharge. There was no difference detected between survivors and nonsurvivors with recurrent peritonitis in terms of inciting cause, serum albumin concentration, surgical management, or provision of appropriate initial antimicrobials. The survival rate for dogs having recurrent peritonitis was 43.9% (18/41 dogs). This retrospective study did not identify any significant prognostic indicators for dogs with recurrent peritonitis and that the mortality rate for dogs having more than one surgery for septic peritonitis is similar to that reported for a single surgery for septic peritonitis. ©Veterinary Emergency and Critical Care Society 2015.

  12. Distributed medium access control in wireless networks

    CERN Document Server

    Wang, Ping

    2013-01-01

    This brief investigates distributed medium access control (MAC) with QoS provisioning for both single- and multi-hop wireless networks including wireless local area networks (WLANs), wireless ad hoc networks, and wireless mesh networks. For WLANs, an efficient MAC scheme and a call admission control algorithm are presented to provide guaranteed QoS for voice traffic and, at the same time, increase the voice capacity significantly compared with the current WLAN standard. In addition, a novel token-based scheduling scheme is proposed to provide great flexibility and facility to the network servi

  13. Service-Oriented Architecture Afloat: A Capabilities-Based Prioritization Scheme

    Science.gov (United States)

    2013-04-01

    to “information superiority,” ultimately enhancing warfighting capability. Introduction The Program Executive Office for Command, Control...gateway architecture for IP satellite networks with dynamic resource mangement and DiffServ QoS provision. International Journal of Satellite

  14. Enabling Broadband as Commodity within Access Networks: A QoS Recipe

    Science.gov (United States)

    Areizaga, Enrique; Foglar, Andreas; Elizondo, Antonio J.; Geilhardt, Frank

    This paper describes the QoS features that will transform the access networks landscape in order to bring “Broadband” as a commodity while setting up the pillars of the “Future Media Internet”. Quality of Experience is obviously key for emerging and future services. Broadcasting services will first need to equal the QoE of their counterparts in the Open-air market (for IP-TV examples would be artifact-free, no picture freezing, fast zapping times) and offer new features often using interactivity (Time-shifted TV, access to more content, 3DTV with feeling of presence). The huge variety of communications alternatives will lead to different requirements per customer, whose needs will also be dependent on parameters like where the connection is made, the time of the day/day of the week/period of the year or even his/her mood. Today’s networks, designed for providing just Broadband connectivity, will not be enough to satisfy customer’s needs and will necessarily support the introduction of new and innovative services. The Networks of the future should learn from the way the users are communicating, what services they are using, where, when, and how, and adapt accordingly.

  15. Dynamic allocation and admission policies for QoS-aware provisioning systems

    DEFF Research Database (Denmark)

    Mazzucco, M.; Mazzara, M.; Dragoni, Nicola

    2013-01-01

    We present an architecture of a hosting system consisting of a set of hosted web services subject to QoS constraints, and a certain number of servers used to run user's demand. The traffic is session–based, while provider and users agree on SLAs specifying the expected level of service performance...

  16. A Demonstration of Mobility Prediction as a Service in Cloudified LTE Networks

    NARCIS (Netherlands)

    Zhao, Zhongliang; Karimzadeh Motallebi Azar, Morteza; Braun, Torsten; Pras, Aiko; van den Berg, Hans Leo

    2015-01-01

    Location prediction has attracted a significant amount of research effort. Being able to predict users’ movement benefits a wide range of communication systems, including location-based service/applications, mobile access control, mobile QoS provision, and resource management for mobile computation

  17. On QoS guarantee in MPLS network with software deadline awareness

    Science.gov (United States)

    Gao, Yu; Jin, Yaohui; Cheng, Hong; Yu, Yingdi; Sun, Weiqiang; Guo, Wei; Hu, Weisheng

    2007-11-01

    With the increasing number of internet users, more and more real-time services are added into the network, such as IPTV, online-video, Voice over IP, etc. As we know, throughput is a highly important performance criterion for scheduling algorithms of networks. Besides throughput, these growing real-time services are very sensitive to delay variance termed as jitter. Therefore, high performance scheduling algorithm should achieve good performance in terms of throughput, delay, jitter and fairness together. Scheduling algorithm with deadline-awareness employed in packet switching plays a key role in QoS guarantees. Although traditional hard-deadline can provide guarantee on in-node delay-deadline criteria, the end-to-end delay-deadline criteria cannot be guaranteed due to the characteristic of hard-deadline, while the delay-deadline guaranteed throughput is low. Thus, soft-deadline scheduling algorithm has been proposed. In this paper, we investigate and compare the classical hard-deadline and soft-deadline switching algorithm. A new scheme "Bonus System" is proposed in order to realize the idea of soft-deadline switching algorithm. Bonus System based on soft-deadline is compared with classical Early-Deadline First scheme based on hard-deadline, which shows that Bonus System has better performance in End-to-End deadline guarantee.

  18. An Adaptive QoS Routing Solution for MANET Based Multimedia Communications in Emergency Cases

    Science.gov (United States)

    Ramrekha, Tipu Arvind; Politis, Christos

    The Mobile Ad hoc Networks (MANET) is a wireless network deprived of any fixed central authoritative routing entity. It relies entirely on collaborating nodes forwarding packets from source to destination. This paper describes the design, implementation and performance evaluation of CHAMELEON, an adaptive Quality of Service (QoS) routing solution, with improved delay and jitter performances, enabling multimedia communication for MANETs in extreme emergency situations such as forest fire and terrorist attacks as defined in the PEACE project. CHAMELEON is designed to adapt its routing behaviour according to the size of a MANET. The reactive Ad Hoc on-Demand Distance Vector Routing (AODV) and proactive Optimized Link State Routing (OLSR) protocols are deemed appropriate for CHAMELEON through their performance evaluation in terms of delay and jitter for different MANET sizes in a building fire emergency scenario. CHAMELEON is then implemented in NS-2 and evaluated similarly. The paper concludes with a summary of findings so far and intended future work.

  19. QoS Differentiated and Fair Packet Scheduling in Broadband Wireless Access Networks

    Directory of Open Access Journals (Sweden)

    Zhang Yan

    2009-01-01

    Full Text Available This paper studies the packet scheduling problem in Broadband Wireless Access (BWA networks. The key difficulties of the BWA scheduling problem lie in the high variability of wireless channel capacity and the unknown model of packet arrival process. It is difficult for traditional heuristic scheduling algorithms to handle the situation and guarantee satisfying performance in BWA networks. In this paper, we introduce learning-based approach for a better solution. Specifically, we formulate the packet scheduling problem as an average cost Semi-Markov Decision Process (SMDP. Then, we solve the SMDP by using reinforcement learning. A feature-based linear approximation and the Temporal-Difference learning technique are employed to produce a near optimal solution of the corresponding SMDP problem. The proposed algorithm, called Reinforcement Learning Scheduling (RLS, has in-built capability of self-training. It is able to adaptively and timely regulate its scheduling policy according to the instantaneous network conditions. Simulation results indicate that RLS outperforms two classical scheduling algorithms and simultaneously considers: (i effective QoS differentiation, (ii high bandwidth utilization, and (iii both short-term and long-term fairness.

  20. QoS prediction for web services based on user-trust propagation model

    Science.gov (United States)

    Thinh, Le-Van; Tu, Truong-Dinh

    2017-10-01

    There is an important online role for Web service providers and users; however, the rapidly growing number of service providers and users, it can create some similar functions among web services. This is an exciting area for research, and researchers seek to to propose solutions for the best service to users. Collaborative filtering (CF) algorithms are widely used in recommendation systems, although these are less effective for cold-start users. Recently, some recommender systems have been developed based on social network models, and the results show that social network models have better performance in terms of CF, especially for cold-start users. However, most social network-based recommendations do not consider the user's mood. This is a hidden source of information, and is very useful in improving prediction efficiency. In this paper, we introduce a new model called User-Trust Propagation (UTP). The model uses a combination of trust and the mood of users to predict the QoS value and matrix factorisation (MF), which is used to train the model. The experimental results show that the proposed model gives better accuracy than other models, especially for the cold-start problem.

  1. Recurrent Meningitis.

    Science.gov (United States)

    Rosenberg, Jon; Galen, Benjamin T

    2017-07-01

    Recurrent meningitis is a rare clinical scenario that can be self-limiting or life threatening depending on the underlying etiology. This review describes the causes, risk factors, treatment, and prognosis for recurrent meningitis. As a general overview of a broad topic, the aim of this review is to provide clinicians with a comprehensive differential diagnosis to aide in the evaluation and management of a patient with recurrent meningitis. New developments related to understanding the pathophysiology of recurrent meningitis are as scarce as studies evaluating the treatment and prevention of this rare disorder. A trial evaluating oral valacyclovir suppression after HSV-2 meningitis did not demonstrate a benefit in preventing recurrences. The data on prophylactic antibiotics after basilar skull fractures do not support their use. Intrathecal trastuzumab has shown promise in treating leptomeningeal carcinomatosis from HER-2 positive breast cancer. Monoclonal antibodies used to treat cancer and autoimmune diseases are new potential causes of drug-induced aseptic meningitis. Despite their potential for causing recurrent meningitis, the clinical entities reviewed herein are not frequently discussed together given that they are a heterogeneous collection of unrelated, rare diseases. Epidemiologic data on recurrent meningitis are lacking. The syndrome of recurrent benign lymphocytic meningitis described by Mollaret in 1944 was later found to be closely related to HSV-2 reactivation, but HSV-2 is by no means the only etiology of recurrent aseptic meningitis. While the mainstay of treatment for recurrent meningitis is supportive care, it is paramount to ensure that reversible and treatable causes have been addressed for further prevention.

  2. Advance Network Reservation and Provisioning for Science

    Energy Technology Data Exchange (ETDEWEB)

    Balman, Mehmet; Chaniotakis, Evangelos; Shoshani, Arie; Sim, Alex

    2009-07-10

    guaranteed bandwidth of secure virtual circuits at a certain time, for a certain bandwidth and length of time. Though OSCARS operates within the ESnet, it also supplies end-to-end provisioning between multiple autonomous network domains. OSCARS gets reservation requests through a standard web service interface, and conducts a Quality-of-service (QoS) path for bandwidth guarantees. Multi-protocol Label Switching (MPLS) and the Resource Reservation Protocol (RSVP) enable to create a virtual circuit using Label Switched Paths (LSP's). It contains three main components: a reservation manager, a bandwidth scheduler, and a path setup subsystem. The bandwidth scheduler needs to have information about the current and future states of the network topology in order to accomplish end-to-end bandwidth guaranteed paths.

  3. Modelo de asignación predictivo de longitudes de ondas en redes WDM teniendo en cuenta dispersión residual y tráficos unicast/multicast con QoS

    Directory of Open Access Journals (Sweden)

    Javier Sierra

    2009-01-01

    Full Text Available El tráfico de Internet está en constante crecimiento y con él las aplicaciones del tipo unicast/multicast con diferentes requerimientos de Calidad de Servicio (QoS. Esto es motivo para que las Redes de Transporte Ópticas (OTN deban continuar su evolución hacia redes completamente ópticas (sin conversiones Óptico-Electrónico-Óptico: OEO. S/G Light-tree es una arquitectura de los nodos de las redes all-OTN que permite el optimo enrutamiento y/o manejo de tráficos unicast/multicast empleando el concepto de Traffic Grooming (TG, granularidad de tráfico en un ambiente óptico. Las técnicas de grooming así como los algoritmos de asignación y enrutamiento propuestos hasta el momento no tienen en cuenta los fenómenos que se pueden prestar en la fibra óptica, los cuales atenúan o alteran las diferentes longitudes de onda en las redes WDM (Wavelength Division Multiplexing. La dispersión cromática es un fenómeno que deforma los pulsos transmitidos en una fibra óptica y el efecto depende de la longitud de onda empleada en la transmisión. En este artículo, se propone un modelo predictivo de asignación de longitudes de ondas basado en cadenas de Markov que tiene en cuenta la dispersión residual en redes WDM que soportan traffic grooming y tráficos unicast/multicast con requerimientos de QoS. Los resultados de las simulaciones realizadas muestran que el modelo propuesto mejora la probabilidad de bloqueo de tráficos con requerimientos de QoS.

  4. Impacto de Parámetros de QoS en Aspectos de QoE: Análisis desde el Punto de Vista de la Sincronización Multimedia

    NARCIS (Netherlands)

    M.A. Montagud Climent (Mario); F. Boronat (Fernando); M. Martinez; J. Belda (Jordi); P.S. Cesar Garcia (Pablo Santiago)

    2015-01-01

    htmlabstractLa sincronización multimedia ha sido un área de investigación clave desde los inicios de los sistemas multimedia. En este artículo se ofrecen una visión general y un análisis sobre el impacto de varios parámetros de QoS en diferentes aspectos de la QoE, desde el punto de vista de la

  5. Predicting quality of experience in multimedia streaming

    NARCIS (Netherlands)

    Menkovski, V.; Oredope, A.; Liotta, A.; Cuadra Sánchez, A.

    2009-01-01

    Measuring and predicting the user’s Quality of Experience (QoE) of a multimedia stream is the first step towards improving and optimizing the provision of mobile streaming services. This enables us to better understand how Quality of Service (QoS) parameters affect service quality, as it is actually

  6. An evaluation of factors predicting breast recurrence and prognosis after recurrence, on distinguishing intramammary and extramammary recurrence, in breast-conserving surgery

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Reiki; Nagao, Kazuharu; Miyayama, Haruhiko [Kumamoto City Hospital (Japan)] (and others)

    2001-06-01

    Recurrence of cancer in the breast is an important problem in breast-conserving therapy. We evaluated risk factors for recurrence from the viewpoint of recurrence type and outcome after recurrence. Of 533 cases of breast cancer treated with breast-conserving surgery from April 1989 through July 2000, disease in 66 recurred (12.4%) and were classified as 23 cases of breast recurrence only, 16 cases of both breast recurrence and distant metastasis, and 27 cases of distant metastasis only. The clinical factors examined included age, lymphatic invasion, nodal status, extensive intraductal component (EIC), proliferative activity, and estrogen receptor (ER) status. Of the 39 cases of breast recurrence, 19 had intramammary tumors and 20 had extramammary tumors of the skin, subcutaneous tissue, or muscle, including 8 cases with inflammatory breast recurrence. Multivariate analysis showed that factors correlated with breast recurrence were age, ER status, proliferative activity, and surgical margin. EIC-comedo was related to intramammary recurrence, whereas lymphatic invasion and nodal status were related to extramammary recurrence. Postoperative irradiation was an effective treatment for tumors in young women and tumors with positive margins or a comedo component. Outcome after breast recurrence depended on nodal status at primary operation, and survival rates were worst in patients with inflammatory breast recurrence. In conclusion, age, EIC-comedo status, the surgical margin, and negative ER status were correlated with breast recurrence. Countermeasures against these factors should be investigated. (author)

  7. An evaluation of factors predicting breast recurrence and prognosis after recurrence, on distinguishing intramammary and extramammary recurrence, in breast-conserving surgery

    International Nuclear Information System (INIS)

    Nishimura, Reiki; Nagao, Kazuharu; Miyayama, Haruhiko

    2001-01-01

    Recurrence of cancer in the breast is an important problem in breast-conserving therapy. We evaluated risk factors for recurrence from the viewpoint of recurrence type and outcome after recurrence. Of 533 cases of breast cancer treated with breast-conserving surgery from April 1989 through July 2000, disease in 66 recurred (12.4%) and were classified as 23 cases of breast recurrence only, 16 cases of both breast recurrence and distant metastasis, and 27 cases of distant metastasis only. The clinical factors examined included age, lymphatic invasion, nodal status, extensive intraductal component (EIC), proliferative activity, and estrogen receptor (ER) status. Of the 39 cases of breast recurrence, 19 had intramammary tumors and 20 had extramammary tumors of the skin, subcutaneous tissue, or muscle, including 8 cases with inflammatory breast recurrence. Multivariate analysis showed that factors correlated with breast recurrence were age, ER status, proliferative activity, and surgical margin. EIC-comedo was related to intramammary recurrence, whereas lymphatic invasion and nodal status were related to extramammary recurrence. Postoperative irradiation was an effective treatment for tumors in young women and tumors with positive margins or a comedo component. Outcome after breast recurrence depended on nodal status at primary operation, and survival rates were worst in patients with inflammatory breast recurrence. In conclusion, age, EIC-comedo status, the surgical margin, and negative ER status were correlated with breast recurrence. Countermeasures against these factors should be investigated. (author)

  8. Aneurysm Recurrence Volumetry Is More Sensitive than Visual Evaluation of Aneurysm Recurrences.

    Science.gov (United States)

    Schönfeld, M H; Schlotfeldt, V; Forkert, N D; Goebell, E; Groth, M; Vettorazzi, E; Cho, Y D; Han, M H; Kang, H-S; Fiehler, J

    2016-03-01

    Considerable inter-observer variability in the visual assessment of aneurysm recurrences limits its use as an outcome parameter evaluating new coil generations. The purpose of this study was to compare visual assessment of aneurysm recurrences and aneurysm recurrence volumetry with an example dataset of HydroSoft coils (HSC) versus bare platinum coils (BPC). For this retrospective study, 3-dimensional time-of-flight magnetic resonance angiography datasets acquired 6 and 12 months after endovascular therapy using BPC only or mainly HSC were analyzed. Aneurysm recurrence volumes were visually rated by two observersas well as quantified by subtraction of the datasets after intensity-based rigid registration. A total of 297 aneurysms were analyzed (BPC: 169, HSC: 128). Recurrences were detected by aneurysm recurrence volumetry in 9 of 128 (7.0 %) treated with HSC and in 24 of 169 (14.2 %) treated with BPC (odds ratio: 2.39, 95 % confidence interval: 1.05-5.48; P = 0.039). Aneurysm recurrence volumetry revealed an excellent correlation between observers (Cronbach's alpha = 0.93). In contrast, no significant difference in aneurysm recurrence was found for visual assessment (3.9 % in HSC cases and 4.7 % in BPC cases). Recurrences were observed in aneurysms smaller than the sample median in 10 of 33 (30.3 %) by aneurysm recurrence volumetry and in 1 of 13 (7.7 %) by visual assessment. Aneurysm recurrences were detected more frequently by aneurysm recurrence volumetry when compared with visual assessment. By using aneurysm recurrence volumetry, differences between treatment groups were detected with higher sensitivity and inter-observer validity probably because of the higher detection rate of recurrences in small aneurysms.

  9. Local Recurrence After Uveal Melanoma Proton Beam Therapy: Recurrence Types and Prognostic Consequences

    International Nuclear Information System (INIS)

    Caujolle, Jean-Pierre; Paoli, Vincent; Chamorey, Emmanuel; Maschi, Celia; Baillif, Stéphanie; Herault, Joël; Gastaud, Pierre; Hannoun-Levi, Jean Michel

    2013-01-01

    Purpose: To study the prognosis of the different types of uveal melanoma recurrences treated by proton beam therapy (PBT). Methods and Materials: This retrospective study analyzed 61 cases of uveal melanoma local recurrences on a total of 1102 patients treated by PBT between June 1991 and December 2010. Survival rates have been determined by using Kaplan-Meier curves. Prognostic factors have been evaluated by using log-rank test or Cox model. Results: Our local recurrence rate was 6.1% at 5 years. These recurrences were divided into 25 patients with marginal recurrences, 18 global recurrences, 12 distant recurrences, and 6 extrascleral extensions. Five factors have been identified as statistically significant risk factors of local recurrence in the univariate analysis: large tumoral diameter, small tumoral volume, low ratio of tumoral volume over eyeball volume, iris root involvement, and safety margin inferior to 1 mm. In the local recurrence-free population, the overall survival rate was 68.7% at 10 years and the specific survival rate was 83.6% at 10 years. In the local recurrence population, the overall survival rate was 43.1% at 10 years and the specific survival rate was 55% at 10 years. The multivariate analysis of death risk factors has shown a better prognosis for marginal recurrences. Conclusion: Survival rate of marginal recurrences is superior to that of the other recurrences. The type of recurrence is a clinical prognostic value to take into account. The influence of local recurrence retreatment by proton beam therapy should be evaluated by novel studies

  10. Local Recurrence After Uveal Melanoma Proton Beam Therapy: Recurrence Types and Prognostic Consequences

    Energy Technology Data Exchange (ETDEWEB)

    Caujolle, Jean-Pierre, E-mail: ncaujolle@aol.com [Department of Ophthalmology, Saint Roch Hospital, Nice Teaching Hospital, Nice (France); Paoli, Vincent [Department of Ophthalmology, Saint Roch Hospital, Nice Teaching Hospital, Nice (France); Chamorey, Emmanuel [Department of Radiation Oncology, Protontherapy Center, Centre Antoine Lacassagne, Nice (France); Department of Biostatistics and Epidemiology, Centre Antoine Lacassagne, Nice (France); Maschi, Celia; Baillif, Stéphanie [Department of Ophthalmology, Saint Roch Hospital, Nice Teaching Hospital, Nice (France); Herault, Joël [Department of Radiation Oncology, Protontherapy Center, Centre Antoine Lacassagne, Nice (France); Gastaud, Pierre [Department of Ophthalmology, Saint Roch Hospital, Nice Teaching Hospital, Nice (France); Hannoun-Levi, Jean Michel [Department of Radiation Oncology, Protontherapy Center, Centre Antoine Lacassagne, Nice (France)

    2013-04-01

    Purpose: To study the prognosis of the different types of uveal melanoma recurrences treated by proton beam therapy (PBT). Methods and Materials: This retrospective study analyzed 61 cases of uveal melanoma local recurrences on a total of 1102 patients treated by PBT between June 1991 and December 2010. Survival rates have been determined by using Kaplan-Meier curves. Prognostic factors have been evaluated by using log-rank test or Cox model. Results: Our local recurrence rate was 6.1% at 5 years. These recurrences were divided into 25 patients with marginal recurrences, 18 global recurrences, 12 distant recurrences, and 6 extrascleral extensions. Five factors have been identified as statistically significant risk factors of local recurrence in the univariate analysis: large tumoral diameter, small tumoral volume, low ratio of tumoral volume over eyeball volume, iris root involvement, and safety margin inferior to 1 mm. In the local recurrence-free population, the overall survival rate was 68.7% at 10 years and the specific survival rate was 83.6% at 10 years. In the local recurrence population, the overall survival rate was 43.1% at 10 years and the specific survival rate was 55% at 10 years. The multivariate analysis of death risk factors has shown a better prognosis for marginal recurrences. Conclusion: Survival rate of marginal recurrences is superior to that of the other recurrences. The type of recurrence is a clinical prognostic value to take into account. The influence of local recurrence retreatment by proton beam therapy should be evaluated by novel studies.

  11. Recurrent Intracerebral Hemorrhage

    DEFF Research Database (Denmark)

    Schmidt, Linnea Boegeskov; Goertz, Sanne; Wohlfahrt, Jan

    2016-01-01

    BACKGROUND: Intracerebral hemorrhage (ICH) is a disease with high mortality and a substantial risk of recurrence. However, the recurrence risk is poorly documented and the knowledge of potential predictors for recurrence among co-morbidities and medicine with antithrombotic effect is limited....... OBJECTIVES: 1) To estimate the short- and long-term cumulative risks of recurrent intracerebral hemorrhage (ICH). 2) To investigate associations between typical comorbid diseases, surgical treatment, use of medicine with antithrombotic effects, including antithrombotic treatment (ATT), selective serotonin...

  12. Intelligent QoS routing algorithm based on improved AODV protocol for Ad Hoc networks

    Science.gov (United States)

    Huibin, Liu; Jun, Zhang

    2016-04-01

    Mobile Ad Hoc Networks were playing an increasingly important part in disaster reliefs, military battlefields and scientific explorations. However, networks routing difficulties are more and more outstanding due to inherent structures. This paper proposed an improved cuckoo searching-based Ad hoc On-Demand Distance Vector Routing protocol (CSAODV). It elaborately designs the calculation methods of optimal routing algorithm used by protocol and transmission mechanism of communication-package. In calculation of optimal routing algorithm by CS Algorithm, by increasing QoS constraint, the found optimal routing algorithm can conform to the requirements of specified bandwidth and time delay, and a certain balance can be obtained among computation spending, bandwidth and time delay. Take advantage of NS2 simulation software to take performance test on protocol in three circumstances and validate the feasibility and validity of CSAODV protocol. In results, CSAODV routing protocol is more adapt to the change of network topological structure than AODV protocol, which improves package delivery fraction of protocol effectively, reduce the transmission time delay of network, reduce the extra burden to network brought by controlling information, and improve the routing efficiency of network.

  13. Recurrent Childhood Animal Cruelty and Its Link to Recurrent Adult Interpersonal Violence.

    Science.gov (United States)

    Trentham, Caleb E; Hensley, Christopher; Policastro, Christina

    2018-06-01

    In the early 1960s, researchers began to examine the potential link between childhood animal cruelty and future interpersonal violence. Findings since then have been inconsistent in establishing a relationship between the two. This may be due to researchers failing to measure the recurrency of childhood animal abuse and the recurrency of later violent acts committed in adulthood. The current study, using data from 257 inmates at a medium-security prison in a Southern state, is a replication of research conducted by Tallichet and Hensley, and Hensley, Tallichet, and Dutkiewicz, which examined this recurrency issue. The only statistically significant predictor of recurrent adult interpersonal violence in this study was recurrent childhood animal cruelty. Inmates who engaged in recurrent childhood animal cruelty were more likely to commit recurrent adult interpersonal violence. Respondents' race, education, and childhood residence were not significant predictors of the outcome variable.

  14. A Practical Perspective on the Design and Implementation of Enterprise Integration Solution to improve QoS using SAP NetWeaver Platform

    Directory of Open Access Journals (Sweden)

    K.Krishna Mohan

    2010-06-01

    Full Text Available Most of the enterprise operations require information from several systems within and outside the enterprise(s. The past few years have seen explosive growth in direct program to program interaction for application integration, removing manual steps yielding tremendous improvements in reliability and efficiency. This paper addresses the practical approach for the design and implementation of Enterprise Application Integration in a heterogeneous environment with SAP NetWeaver Platform (i.e. Exchange Infrastructure (XI/Process Integration (PI using a Customizable Tool named TEmplate based Functional Requirements for Integration Design (TEFRID developed by the author(s to improve the Quality of Service (QoS and reduce the development time and cost with the end-to-end scenario development.

  15. On the end-user QoS-awareness of a distributed service environment

    NARCIS (Netherlands)

    Widya, I.; Stap, R.E.; Teunissen, L.J.; Hopman, B.F.

    2001-01-01

    A lot of attention has been given to network quality of service and efforts to make layers on top of the network also QoS-aware increase noticeably. This paper explores QoS-aware service provisioning at a level close to end-user's perception. It shows how end-user oriented QoS requirements have been

  16. Recurrent Takotsubo Cardiomyopathy Related to Recurrent Thyrotoxicosis.

    Science.gov (United States)

    Patel, Keval; Griffing, George T; Hauptman, Paul J; Stolker, Joshua M

    2016-04-01

    Takotsubo cardiomyopathy, or transient left ventricular apical ballooning syndrome, is characterized by acute left ventricular dysfunction caused by transient wall-motion abnormalities of the left ventricular apex and mid ventricle in the absence of obstructive coronary artery disease. Recurrent episodes are rare but have been reported, and several cases of takotsubo cardiomyopathy have been described in the presence of hyperthyroidism. We report the case of a 55-year-old woman who had recurrent takotsubo cardiomyopathy, documented by repeat coronary angiography and evaluations of left ventricular function, in the presence of recurrent hyperthyroidism related to Graves disease. After both episodes, the patient's left ventricular function returned to normal when her thyroid function normalized. These findings suggest a possible role of thyroid-hormone excess in the pathophysiology of some patients who have takotsubo cardiomyopathy.

  17. Recurrent hamburger thyrotoxicosis

    Science.gov (United States)

    Parmar, Malvinder S.; Sturge, Cecil

    2003-01-01

    RECURRENT EPISODES OF SPONTANEOUSLY RESOLVING HYPERTHYROIDISM may be caused by release of preformed hormone from the thyroid gland after it has been damaged by inflammation (recurrent silent thyroiditis) or by exogenous administration of thyroid hormone, which might be intentional or surreptitious (thyrotoxicosis factitia). Community-wide outbreaks of “hamburger thyrotoxicosis” resulting from inadvertent consumption of beef contaminated with bovine thyroid gland have been previously reported. Here we describe a single patient who experienced recurrent episodes of this phenomenon over an 11-year period and present an approach to systematically evaluating patients with recurrent hyperthyroidism. PMID:12952802

  18. 75 FR 15777 - Common Crop Insurance Regulations, Basic Provisions; and Various Crop Insurance Provisions

    Science.gov (United States)

    2010-03-30

    ... (protection for production losses only) within one Basic Provisions and the applicable Crop Provisions to..., Macadamia Nut Crop Insurance Provisions, Onion Crop Insurance Provisions, Dry Pea Crop Insurance Provisions... (protection for production losses only) and revenue protection (protection against loss of revenue caused by...

  19. Downlink Radio Resource Management for QoS Provisioning in OFDMA Systems

    DEFF Research Database (Denmark)

    Monghal, Guillaume Damien

    Admission Control solution for a realistic OFDMA based system in downlink where LTE is taken as a case study. In the frame of the thesis work, a detailed system model of LTE dedicated to Radio Resource Management study has been developed and implemented in a semi-static system level simulator. In a first...... phase, the study focuses on the dual time / frequency domain packet scheduling concept which allows a linear complexity. Fundamental design principles for throughput control are highlighted. Using those principles, the design of a complete Quality of Service aware packet scheduling algorithm based...

  20. Context-aware QoS provisioning for an M-health service platform

    NARCIS (Netherlands)

    Wac, K.E.; Delgado Kloos, C.; Larrabeiti, D.; van Halteren, Aart; Bults, Richard G.A.; Lopez, A.M.; Broens, T.H.F.

    Inevitably, healthcare goes mobile. Recently developed mobile healthcare (i.e., m-health) services allow healthcare professionals to monitor mobile patient’s vital signs and provide feedback to this patient anywhere at any time. Due to the nature of current supporting mobile service platforms,

  1. Women's Management of Recurrent Bacterial Vaginosis and Experiences of Clinical Care: A Qualitative Study.

    Directory of Open Access Journals (Sweden)

    Jade Bilardi

    Full Text Available Few data are available on how women manage recurring bacterial vaginosis (BV and their experiences of the clinical care of this condition. This study aimed to explore women's recurrent BV management approaches and clinical care experiences, with a view to informing and improving the clinical management of BV.A descriptive, social constructionist approach was chosen as the framework for the study. Thirty-five women of varying sexual orientation who had experienced recurrent BV in the past 5 years took part in semi-structured interviews.The majority of women reported frustration and dissatisfaction with current treatment regimens and low levels of satisfaction with the clinical management of BV. Overall, women disliked taking antibiotics regularly, commonly experienced adverse side effects from treatment and felt frustrated at having symptoms recur quite quickly after treatment. Issues in clinical care included inconsistency in advice, misdiagnosis and inappropriate diagnostic approaches and insensitive or dismissive attitudes. Women were more inclined to report positive clinical experiences with sexual health physicians than primary care providers. Women's frustrations led most to try their own self-help remedies and lifestyle modifications in an attempt to treat symptoms and prevent recurrences, including well-known risk practices such as douching.In the face of considerable uncertainty about the cause of BV, high rates of recurrence, unacceptable treatment options and often insensitive and inconsistent clinical management, women are trying their own self-help remedies and lifestyle modifications to prevent recurrences, often with little effect. Clinical management of BV could be improved through the use of standardised diagnostic approaches, increased sensitivity and understanding of the impact of BV, and the provision of evidence based advice about known BV related risk factors.

  2. Service differentiated and adaptive CSMA/CA over IEEE 802.15.4 for Cyber-Physical Systems.

    Science.gov (United States)

    Xia, Feng; Li, Jie; Hao, Ruonan; Kong, Xiangjie; Gao, Ruixia

    2013-01-01

    Cyber-Physical Systems (CPS) that collect, exchange, manage information, and coordinate actions are an integral part of the Smart Grid. In addition, Quality of Service (QoS) provisioning in CPS, especially in the wireless sensor/actuator networks, plays an essential role in Smart Grid applications. IEEE 802.15.4, which is one of the most widely used communication protocols in this area, still needs to be improved to meet multiple QoS requirements. This is because IEEE 802.15.4 slotted Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA) employs static parameter configuration without supporting differentiated services and network self-adaptivity. To address this issue, this paper proposes a priority-based Service Differentiated and Adaptive CSMA/CA (SDA-CSMA/CA) algorithm to provide differentiated QoS for various Smart Grid applications as well as dynamically initialize backoff exponent according to traffic conditions. Simulation results demonstrate that the proposed SDA-CSMA/CA scheme significantly outperforms the IEEE 802.15.4 slotted CSMA/CA in terms of effective data rate, packet loss rate, and average delay.

  3. Quality of Services in Integrated UMTS/IP Networks

    Directory of Open Access Journals (Sweden)

    Ivan Bošnjak

    2006-01-01

    Full Text Available Fast development and implementation of new telecommunicationservices and Intelligent Transp01t Systems (ITS havecreated new environment for the network telecom operatorsand service providers and logistic and transport enterprises. Thecmcial issue for successful business and other professional applicationsis the provision of the end-to-end quality of service inthe inter-network operation of mobile and fixed networks. Theproblem was less expressed in the traditional networks orientedto telephony, but the issue of different QoS algorithms growswith the spreading of data transmission services and multimediaapplications. The existence of different QoS algorithms andprocedures in the !?-based networks (JP- Internet Protocolalso makes difficult the finding of a single solution for the implementationofQoS in the !?-based networks. In the indicatedcontext this work systemically defines the problem of providinga single end-to-end QoS protocol in the connected UMTS/IPnetworks. The possibilities of its realization are presented on theexample of two protocols. The work gives the basic characteristicsof the two protocols that fulfil the criteria set in the realizationof the new generation of mobile networks.

  4. Predictors of recurrence in pheochromocytoma.

    Science.gov (United States)

    Press, Danielle; Akyuz, Muhammet; Dural, Cem; Aliyev, Shamil; Monteiro, Rosebel; Mino, Jeff; Mitchell, Jamie; Hamrahian, Amir; Siperstein, Allan; Berber, Eren

    2014-12-01

    The recurrence rate of pheochromocytoma after adrenalectomy is 6.5-16.5%. This study aims to identify predictors of recurrence and optimal biochemical testing and imaging for detecting the recurrence of pheochromocytoma. In this retrospective study we reviewed all patients who underwent adrenalectomy for pheochromocytoma during a 14-year period at a single institution. One hundred thirty-five patients had adrenalectomy for pheochromocytoma. Eight patients (6%) developed recurrent disease. The median time from initial operation to diagnosis of recurrence was 35 months. On multivariate analysis, tumor size >5 cm was an independent predictor of recurrence. One patient with recurrence died, 4 had stable disease, 2 had progression of disease, and 1 was cured. Recurrence was diagnosed by increases in plasma and/or urinary metanephrines and positive imaging in 6 patients (75%), and by positive imaging and normal biochemical levels in 2 patients (25%). Patients with large tumors (>5 cm) should be followed vigilantly for recurrence. Because 25% of patients with recurrence had normal biochemical levels, we recommend routine imaging and testing of plasma or urinary metanephrines for prompt diagnosis of recurrence. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Recurrence in affective disorder

    DEFF Research Database (Denmark)

    Kessing, L V; Olsen, E W; Andersen, P K

    1999-01-01

    The risk of recurrence in affective disorder is influenced by the number of prior episodes and by a person's tendency toward recurrence. Newly developed frailty models were used to estimate the effect of the number of episodes on the rate of recurrence, taking into account individual frailty toward...... recurrence. The study base was the Danish psychiatric case register of all hospital admissions for primary affective disorder in Denmark during 1971-1993. A total of 20,350 first-admission patients were discharged with a diagnosis of major affective disorder. For women with unipolar disorder and for all...... kinds of patients with bipolar disorder, the rate of recurrence was affected by the number of prior episodes even when the effect was adjusted for individual frailty toward recurrence. No effect of episodes but a large effect of the frailty parameter was found for unipolar men. The authors concluded...

  6. Persistent and recurrent hyperparathyroidism.

    Science.gov (United States)

    Guerin, Carole; Paladino, Nunzia Cinzia; Lowery, Aoife; Castinetti, Fréderic; Taieb, David; Sebag, Fréderic

    2017-06-01

    Despite remarkable progress in imaging modalities and surgical management, persistence or recurrence of primary hyperparathyroidism (PHPT) still occurs in 2.5-5% of cases of PHPT. The aim of this review is to expose the management of persistent and recurrent hyperparathyroidism. A literature search was performed on MEDLINE using the search terms "recurrent" or "persistent" and "hyperparathyroidism" within the past 10 years. We also searched the reference lists of articles identified by this search strategy and selected those we judged relevant. Before considering reoperation, the surgeon must confirm the diagnosis of PHPT. Then, the patient must be evaluated with new imaging modalities. A single adenoma is found in 68% of cases, multiglandular disease in 28%, and parathyroid carcinoma in 3%. Others causes (<1%) include parathyromatosis and graft recurrence. The surgeon must balance the benefits against the risks of a reoperation (permanent hypocalcemia and recurrent laryngeal nerve palsy). If surgery is necessary, a focused approach can be considered in cases of significant imaging foci, but in the case of multiglandular disease, a bilateral neck exploration could be necessary. Patients with multiple endocrine neoplasia syndromes are at high risk of recurrence and should be managed regarding their hereditary pathology. The cure rate of persistent-PHPT or recurrent-PHPT in expert centers is estimated from 93 to 97%. After confirming the diagnosis of PHPT, patients with persistent-PHPT and recurrent-PHPT should be managed in an expert center with all dedicated competencies.

  7. Ethanol ablation of predominantly cystic thyroid nodules: Evaluation of recurrence rate and factors related to recurrence

    International Nuclear Information System (INIS)

    Suh, C.H.; Baek, J.H.; Ha, E.J.; Choi, Y.J.; Lee, J.H.; Kim, J.K.; Chung, K.-W.; Kim, T.Y.; Kim, W.B.; Shong, Y.K.

    2015-01-01

    Aim: To evaluate recurrence rate and associated risk factors for recurrence after ethanol ablation (EA) in patients with predominantly cystic thyroid nodules. Materials and methods: This observational study was approved by the Ethics Committee of the Institutional Review Board and informed consent for procedures was obtained. From April 2009 to April 2013, 107 consecutive patients with predominantly cystic nodules were treated using EA. Recurrence was defined as nodules showing a residual solid portion with internal vascularity, cosmetic problems remaining, or persistent symptoms, and patients who requested additional therapy to resolve their symptomatic or cosmetic problems. Delayed recurrence was defined as treated nodules that showed no recurrent features at 1 month, but showed newly developed recurrent features during the longer follow-up period. Multivariate analysis was used for variables to demonstrate the independent factors related to volume reduction. Results: One month after EA, 18.7% of patients (20/107) showed recurrence. Among 87 patients with non-recurrence, 24.1% (21/87) showed delayed recurrence. The total recurrence rate was 38.3% (41/107). Patients with recurrence (n = 41) were treated using radiofrequency ablation (n = 28), second EA (n = 4), and refused further treatment (n = 9). These patients responded well to repeat EA and radiofrequency ablation. Multivariate analysis demonstrated that the initial nodule volume (>20 ml; p < 0.036) and vascularity (grade >1; p < 0.049) were independent predictors of volume reduction at last follow-up. Conclusions: The results revealed that although EA seemed to be effective during the initial period, delayed recurrence should be considered during longer-term follow-up. The independent predictors of recurrence were initial volume (>20 ml) and vascularity. - Highlights: • Ethanol ablation showed unsatisfactory results in 18.7% of patient at one month. • Delayed recurrence was observed in 24

  8. Link Power Budget and Traffict QoS Performance Analysis of Gygabit Passive Optical Network

    Science.gov (United States)

    Ubaidillah, A.; Alfita, R.; Toyyibah

    2018-01-01

    Data service of telecommunication network is needed widely in the world; therefore extra wide bandwidth must be provided. For this case, PT. Telekomunikasi Tbk. applies GPON (Gigabit Passive Optical Network) as optical fibre based on telecommunication network system. GPON is a point to a multipoint technology of FTTx (Fiber to The x) that transmits information signals to the subscriber over optical fibre. In GPON trunking system, from OLT (Optical Line Terminal), the network is split to many ONT (Optical Network Terminal) of the subscribers, so it causes path loss and attenuation. In this research, the GPON performance is measured from the link power budget system and the Quality of Service (QoS) of the traffic. And the observation result shows that the link power budget system of this GPON is in good condition. The link power budget values from the mathematical calculation and direct measurement are satisfy the ITU-T G984 Class B standard, that the power level must be between -8 dBm to -27 dBm. While from the traffic performance, the observation result shows that the network resource utility of the subscribers of the observed area is not optimum. The mean of subscriber utility rate is 27.985 bps for upstream and 79.687 bps for downstream. While maximally, It should be 60.800 bps for upstream and 486.400 bps for downstream.

  9. Recurrent intussusception in children and infants

    Directory of Open Access Journals (Sweden)

    Amine Ksia

    2013-01-01

    Full Text Available Background: Recurrent intussusceptions in child and infants are problematic and there are controversies about its management. The aim of this study is to determine the details of the clinical diagnosis of recurrent intussusception and to determine the aetiology of recurrent intussusceptions. Patients and Methods: It′s a retrospective study of 28 cases of recurrent intussusception treated in the paediatric surgery department of Monastir (Tunisia between January 1998 and December 2011. Results: During the study period, 505 patients were treated for 544 episodes of intussusception; there were 39 episodes of recurrent intussusceptions in 28 patients; the rate of patients with recurrence was 5.5%. With comparison to the initial episode, clinical features were similar to the recurrent episode, except bloody stool that was absent in the recurrent group (P = 0,016. Only one patient had a pathologic local point. Conclusion: In recurrent intussusception, patients are less symptomatic and consult quickly. Systematic surgical exploration is not needed as recurrent intussusceptions are easily reduced by air or hydrostatic enema and are not associated with a high rate of pathologic leading points.

  10. АДАПТИВНЕ ЗАБЕЗПЕЧЕННЯ QOS НА ОСНОВІ МОДИФІКОВАНОГО АЛГОРИТМУ АКТИВНОГО КЕРУВАННЯ ЧЕРГАМИ

    Directory of Open Access Journals (Sweden)

    СЛАВКО Олена Геннадіївна

    2012-12-01

    Full Text Available Functions of data transferring control in NGN networks, that related to Quality of Service (QoS providing for network data, are examined. The scheme of decision for network packets admission to service in general scheme of QoS providing is offered. This scheme is based on queues management of network routers buffers using the modified algorithm ARED (Adaptive Random Early Detection.

  11. Recurrent Kawasaki disease: USA and Japan.

    Science.gov (United States)

    Maddox, Ryan A; Holman, Robert C; Uehara, Ritei; Callinan, Laura S; Guest, Jodie L; Schonberger, Lawrence B; Nakamura, Yosikazu; Yashiro, Mayumi; Belay, Ermias D

    2015-12-01

    Descriptive epidemiologic studies of recurrent and non-recurrent Kawasaki disease (KD) may identify other potentially important differences between these illnesses. Data from the USA and Japan, the Centers for Disease Control and Prevention (CDC) national KD surveillance(1984-2008) and the 17th Japanese nationwide survey (2001-2002), respectively, were analyzed to examine recurrent KD patients <18 years of age meeting the CDC KD case or atypical KD case definition. These patients were compared with non-recurrent KD patients. Of the 5557 US KD patients <18 years of age during 1984-2008, 97 (1.7%) were identified as having had recurrent KD. Among the US Asian/Pacific Islander KD patients, 3.5% had recurrent KD, which was similar to the percentage identified among KD patients (3.5%) in the Japanese survey. Compared with non-recurrent KD patients, KD patients [with recurrent KD] were more likely to be older, fulfill the atypical KD case definition, and have coronary artery abnormalities (CAA) despite i.v. immunoglobulin (IVIG) treatment. Differences in the age, race, and frequency of CAA exist between recurrent and non-recurrent KD patients. The increased association of CAA with recurrent KD suggests that more aggressive treatment strategies in conjunction with IVIG may be indicated for the second episode of KD. © 2015 Japan Pediatric Society.

  12. To what extent does recurrent government health expenditure in Uganda reflect its policy priorities?

    Directory of Open Access Journals (Sweden)

    Nabyonga-Orem Juliet

    2010-10-01

    Full Text Available Abstract Background The National Health Policy 2000 - 2009 and Health sector strategic plans I & II emphasized that Primary Health Care (PHC would be the main strategy for national development and would be operationalized through provision of the minimum health care package. Commitment was to spend an increasing proportion of the health budget for the provision of the basic minimum package of health services which was interpreted to mean increasing spending at health centre level. This analysis was undertaken to gain a better understanding of changes in the way recurrent funding is allocated in the health sector in Uganda and to what extent it has been in line with agreed policy priorities. Methods Government recurrent wage and non-wage expenditures - based on annual releases by the Uganda Ministry of Finance, Planning and Economic Development were compiled for the period 1997/1998 to financial year 2007/2008. Additional data was obtained from a series of Ministry of Health annual health sector reports as well as other reports. Data was verified by key government officials in Ministry of Finance, Planning and Economic Development and Ministry of Health. Analysis of expenditures was done at sector level, by the different levels in the health care system and the different levels of care. Results There was a pronounced increase in the amount of funds released for recurrent expenditure over the review period fueled mainly by increases in the wage component. PHC services showed the greatest increase, increasing more than 70 times in ten years. At hospital level, expenditures remained fairly constant for the last 10 years with a slight reduction in the wage component. Conclusion The policy aspiration of increasing spending on PHC was attained but key aspects that would facilitate its realization were not addressed. At any given level of funding for the health sector, there is need to work out an optimal balance in investment in the different inputs to

  13. Fifth International Symposium on Recurrence Plot

    CERN Document Server

    Riley, Michael; Giuliani, Alessandro; Webber, Charles; Jr, Jr; Translational Recurrences : From Mathematical Theory to Real-World Applications

    2014-01-01

    This book features 13 papers presented at the Fifth International Symposium on Recurrence Plots, held August 2013 in Chicago, IL. It examines recent applications and developments in recurrence plots and recurrence quantifi cation analysis (RQA) with special emphasis on biological and cognitive systems and the analysis of coupled systems using cross-recurrence methods. Readers will discover new applications and insights into a range of systems provided by recurrence plot analysis and new theoretical and mathematical developments in recurrence plots. Recurrence plot based analysis is a powerful tool that operates on real-world complex systems that are nonlinear, non-stationary, noisy, of any statistical distribution, free of any particular model type, and not particularly long. Quantitative analyses promote the detection of system state changes, synchronized dynamical regimes, or classifi cation of system states. Th e book will be of interest to an interdisciplinary audience of recurrence plot users and researc...

  14. Immunomodulators to treat recurrent miscarriage

    NARCIS (Netherlands)

    Prins, Jelmer R.; Kieffer, Tom E.C.; Scherjon, Sicco A.

    2014-01-01

    Recurrent miscarriage is a reproductive disorder affecting many couples. Although several factors are associated with recurrent miscarriage, in more than 50% of the cases the cause is unknown. Maladaptation of the maternal immune system is associated with recurrent miscarriage and could explain part

  15. Chaotic diagonal recurrent neural network

    International Nuclear Information System (INIS)

    Wang Xing-Yuan; Zhang Yi

    2012-01-01

    We propose a novel neural network based on a diagonal recurrent neural network and chaos, and its structure and learning algorithm are designed. The multilayer feedforward neural network, diagonal recurrent neural network, and chaotic diagonal recurrent neural network are used to approach the cubic symmetry map. The simulation results show that the approximation capability of the chaotic diagonal recurrent neural network is better than the other two neural networks. (interdisciplinary physics and related areas of science and technology)

  16. Agent-Based Framework for Personalized Service Provisioning in Converged IP Networks

    Science.gov (United States)

    Podobnik, Vedran; Matijasevic, Maja; Lovrek, Ignac; Skorin-Kapov, Lea; Desic, Sasa

    In a global multi-service and multi-provider market, the Internet Service Providers will increasingly need to differentiate in the service quality they offer and base their operation on new, consumer-centric business models. In this paper, we propose an agent-based framework for the Business-to-Consumer (B2C) electronic market, comprising the Consumer Agents, Broker Agents and Content Agents, which enable Internet consumers to select a content provider in an automated manner. We also discuss how to dynamically allocate network resources to provide end-to-end Quality of Service (QoS) for a given consumer and content provider.

  17. Recurrences of Bell's palsy.

    Science.gov (United States)

    Cirpaciu, D; Goanta, C M; Cirpaciu, M D

    2014-01-01

    Bell's palsy in known as the most common cause of facial paralysis, determined by the acute onset of lower motor neuron weakness of the facial nerve with no detectable cause. With a lifetime risk of 1 in 60 and an annual incidence of 11-40/100,000 population, the condition resolves completely in around 71% of the untreated cases. Clinical trials performed for Bell's palsy have reported some recurrences, ipsilateral or contralateral to the side affected in the primary episode of facial palsy. Only few data are found in the literature. Melkersson-Rosenthal is a rare neuromucocutaneous syndrome characterized by recurrent facial paralysis, fissured tongue (lingua plicata), orofacial edema. We attempted to analyze some clinical and epidemiologic aspects of recurrent idiopathic palsy, and to develop relevant correlations between the existing data in literature and those obtained in this study. This is a retrospective study carried out on a 10-years period for adults and a five-year period for children. A number of 185 patients aged between 4 and 70 years old were analyzed. 136 of them were adults and 49 were children. 22 of 185 patients with Bell's palsy (12%) had a recurrent partial or complete facial paralysis with one to six episodes of palsy. From this group of 22 cases, 5 patients were diagnosed with Melkersson-Rosenthal syndrome. The patients' age was between 4 and 70 years old, with a medium age of 27,6 years. In the group studied, fifteen patients, meaning 68%, were women and seven were men. The majority of patients in our group with more than two facial palsy episodes had at least one episode on the contralateral side. Our study found a significant incidence of recurrences of idiopathic facial palsy. Recurrent idiopathic facial palsy and Melkersson-Rosenthal syndrome is diagnosed more often in young females. Recurrence is more likely to occur in the first two years from the onset, which leads to the conclusion that we should have a follow up of patients

  18. Radiotherapy of Recurrent Uterine Cervical Cancer

    International Nuclear Information System (INIS)

    Ha, Sung Whan; Park, Charn Il; Chai, Kyu Young; Kang, Soon Beom; Lee, Hyo Pyo; Shin, Myon Woo

    1987-01-01

    Forty seven patients with locally recurrent uterine cerival cancer after surgery were treated with radiation during the 6 year period from 1979 through 1984 at the Department of Therapeutic Radiology of Seoul National University Hospital. In 30 out of the 47 patients, recurrence was diagnosed within 2 years after surgery. Site of recurrence was vagina in 19 patients, vagina and parametrium in 21 patients and parametrium only in 7 patients. Complete tumor control was achieved in 35 patients (74.5%) ; the complete response rates were 94.7% (18/19( in vaginal recurrences, 57.1% (12/21) in combined vaginal and parametrial recurrences and 71.4% (5/7) in parametrial recurrences. Overall and disease free survival rates at 4 years were 55.2 and 50.1 percent, respectively, for entire group. Overall 4 year survival rates were 77.0% for vaginal recurrences, 44.1% for vaginal and parametrial recurrences and 42.9% for parametrial recurrences. When the disease extent was classified in the same way as the staging system of FIGO, the 4 year survival was 80.4, 73.0, 25.0 and 0 percent for stage IIa, IIb and IVa, respectively

  19. Recurrence quantification analysis of chimera states

    International Nuclear Information System (INIS)

    Santos, M.S.; Szezech, J.D.; Batista, A.M.; Caldas, I.L.; Viana, R.L.; Lopes, S.R.

    2015-01-01

    Chimera states, characterised by coexistence of coherence and incoherence in coupled dynamical systems, have been found in various physical systems, such as mechanical oscillator networks and Josephson-junction arrays. We used recurrence plots to provide graphical representations of recurrent patterns and identify chimera states. Moreover, we show that recurrence plots can be used as a diagnostic of chimera states and also to identify the chimera collapse. - Highlights: • Chimera states have been found in various physical systems. • Recurrence plots is a graphical method useful to locate recurring patterns. • We used recurrence plots to identify the chimera states. • We show also the recurrence plots can identify the chimera collapse

  20. Recurrence quantification analysis of chimera states

    Energy Technology Data Exchange (ETDEWEB)

    Santos, M.S. [Pós-Graduação em Ciências/Física, Universidade Estadual de Ponta Grossa, 84030-900, Ponta Grossa, PR (Brazil); Szezech, J.D., E-mail: jdanilo@gmail.com [Departamento de Matemática e Estatística, Universidade Estadual de Ponta Grossa, 84030-900, Ponta Grossa, PR (Brazil); Batista, A.M., E-mail: antoniomarcosbatista@gmail.com [Departamento de Matemática e Estatística, Universidade Estadual de Ponta Grossa, 84030-900, Ponta Grossa, PR (Brazil); Caldas, I.L. [Instituto de Física, Universidade de São Paulo, 05315-970, São Paulo, SP (Brazil); Viana, R.L.; Lopes, S.R. [Departamento de Física, Universidade Federal do Paraná, 81531-990, Curitiba, PR (Brazil)

    2015-10-02

    Chimera states, characterised by coexistence of coherence and incoherence in coupled dynamical systems, have been found in various physical systems, such as mechanical oscillator networks and Josephson-junction arrays. We used recurrence plots to provide graphical representations of recurrent patterns and identify chimera states. Moreover, we show that recurrence plots can be used as a diagnostic of chimera states and also to identify the chimera collapse. - Highlights: • Chimera states have been found in various physical systems. • Recurrence plots is a graphical method useful to locate recurring patterns. • We used recurrence plots to identify the chimera states. • We show also the recurrence plots can identify the chimera collapse.

  1. Recurrent vulvovaginitis.

    Science.gov (United States)

    Powell, Anna M; Nyirjesy, Paul

    2014-10-01

    Vulvovaginitis (VV) is one of the most commonly encountered problems by a gynecologist. Many women frequently self-treat with over-the-counter medications, and may present to their health-care provider after a treatment failure. Vulvovaginal candidiasis, bacterial vaginosis, and trichomoniasis may occur as discreet or recurrent episodes, and have been associated with significant treatment cost and morbidity. We present an update on diagnostic capabilities and treatment modalities that address recurrent and refractory episodes of VV. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Chemoradiotherapy response in recurrent rectal cancer

    International Nuclear Information System (INIS)

    Yu, Stanley K T; Bhangu, Aneel; Tait, Diana M; Tekkis, Paris; Wotherspoon, Andrew; Brown, Gina

    2014-01-01

    The efficacy of response to preoperative chemoradiotherapy (CRT) in recurrent versus primary rectal cancer has not been investigated. We compared radiological downsizing between primary and recurrent rectal cancers following CRT and determined the optimal size reduction threshold for response validated by survival outcomes. The proportional change in tumor length for primary and recurrent rectal cancers following CRT was compared using the independent sample t-test. Overall survival (OS) was calculated using the Kaplan–Meier product limit method and differences between survival for tumor size reduction thresholds of 30% (response evaluation criteria in solid tumors [RECIST]), 40%, and 50% after CRT in primary and recurrent rectal cancer groups. A total of 385 patients undergoing CRT were analyzed, 99 with recurrent rectal cancer and 286 with primary rectal cancer. The mean proportional reduction in maximum craniocaudal length was significantly higher for primary rectal tumors (33%) compared with recurrent rectal cancer (11%) (P < 0.01). There was no difference in OS for either primary or recurrent rectal cancer when ≤30% or ≤40% definitions were used. However, for both primary and recurrent tumors, significant differences in median 3-year OS were observed when a RECIST cut-off of 50% was used. OS was 99% versus 77% in primary and 100% versus 42% in recurrent rectal cancer (P = 0.002 and P = 0.03, respectively). Only patients that demonstrated >50% size reduction showed a survival benefit. Recurrent rectal cancer appears radioresistant compared with primary tumors for tumor size after CRT. Further investigation into improving/intensifying chemotherapy and radiotherapy for locally recurrent rectal cancer is justified

  3. Hyperhomocysteinemia in Recurrent Miscarriage

    International Nuclear Information System (INIS)

    Gaber, Kh.R.; Farag, M.K.; Soliman, S.Et.; Abd Al-Kaderm, M.A.

    2008-01-01

    Objective: An elevated total plasma homocysteine level has been suggested as a possible risk factor in women suffering from recurrent pregnancy loss. The current study was undertaken to assess the association between homocysteine, folate, cobalamin (vitamin B12) and the risk of recurrent pregnancy loss. Design: Case . control study Materials and Methods: The study included 57 non-pregnant Egyptian women. They were classified according to their obstetric history into 2 groups: 32 cases with at least two consecutive miscarriages (Study group), and 25 cases with normal obstetric history (Control group). All cases were tested for plasma total homocysteine, serum folate and cobalamin (vitamin B12). Results: The fasting total homocysteine was significantly higher in the study group as compared to the control group. While the median concentrations for the vitamins studied were significantly lower in women of the study group as compared to the controls. Elevated homocysteine and reduced vitamin B12 can be considered risk factors for recurrent miscarriage with odds ratio (OR) and 95% confidence intervals (95% CI) of 1.839 (1.286, 2.63) and 1.993 (1.346, 2.951) respectively in the group of recurrent miscarriages. The OR (95% CI) in the study population for low serum folate concentrations was 1.23 (0.776, 2.256). Conclusion: Elevated homocysteine and reduced serum vitamin B12 are risk factors for recurrent miscarriage. Low serum folate did not seem a risk factor for recurrent miscarriage. Testing for homocysteine levels in women suffering from unexplained recurrent miscarriage and pre-conceptional supplementation with vitamin B12 might be beneficial to improve pregnancy outcome

  4. Hyperhomocysteinemia in Recurrent Miscarriage

    Energy Technology Data Exchange (ETDEWEB)

    Gaber, Kh R; Farag, M K [Prenatal Diagnosis and Fetal Medicine Department, National Research Centre, Dokki, Giza (Egypt); Soliman, S Et [Radioisotope Department, Nuclear Research Centre, Atomic Energy Authority, Cairo (Egypt); Abd Al-Kaderm, M A [Obstetrics and Gynecology Department, Faculty of Medicine, Cairo University, Cairo (Egypt)

    2008-07-01

    Objective: An elevated total plasma homocysteine level has been suggested as a possible risk factor in women suffering from recurrent pregnancy loss. The current study was undertaken to assess the association between homocysteine, folate, cobalamin (vitamin B12) and the risk of recurrent pregnancy loss. Design: Case . control study Materials and Methods: The study included 57 non-pregnant Egyptian women. They were classified according to their obstetric history into 2 groups: 32 cases with at least two consecutive miscarriages (Study group), and 25 cases with normal obstetric history (Control group). All cases were tested for plasma total homocysteine, serum folate and cobalamin (vitamin B12). Results: The fasting total homocysteine was significantly higher in the study group as compared to the control group. While the median concentrations for the vitamins studied were significantly lower in women of the study group as compared to the controls. Elevated homocysteine and reduced vitamin B12 can be considered risk factors for recurrent miscarriage with odds ratio (OR) and 95% confidence intervals (95% CI) of 1.839 (1.286, 2.63) and 1.993 (1.346, 2.951) respectively in the group of recurrent miscarriages. The OR (95% CI) in the study population for low serum folate concentrations was 1.23 (0.776, 2.256). Conclusion: Elevated homocysteine and reduced serum vitamin B12 are risk factors for recurrent miscarriage. Low serum folate did not seem a risk factor for recurrent miscarriage. Testing for homocysteine levels in women suffering from unexplained recurrent miscarriage and pre-conceptional supplementation with vitamin B12 might be beneficial to improve pregnancy outcome.

  5. Exploring a QoS Driven Scheduling Approach for Peer-to-Peer Live Streaming Systems with Network Coding

    Science.gov (United States)

    Cui, Laizhong; Lu, Nan; Chen, Fu

    2014-01-01

    Most large-scale peer-to-peer (P2P) live streaming systems use mesh to organize peers and leverage pull scheduling to transmit packets for providing robustness in dynamic environment. The pull scheduling brings large packet delay. Network coding makes the push scheduling feasible in mesh P2P live streaming and improves the efficiency. However, it may also introduce some extra delays and coding computational overhead. To improve the packet delay, streaming quality, and coding overhead, in this paper are as follows. we propose a QoS driven push scheduling approach. The main contributions of this paper are: (i) We introduce a new network coding method to increase the content diversity and reduce the complexity of scheduling; (ii) we formulate the push scheduling as an optimization problem and transform it to a min-cost flow problem for solving it in polynomial time; (iii) we propose a push scheduling algorithm to reduce the coding overhead and do extensive experiments to validate the effectiveness of our approach. Compared with previous approaches, the simulation results demonstrate that packet delay, continuity index, and coding ratio of our system can be significantly improved, especially in dynamic environments. PMID:25114968

  6. Multi-Objective Resource Allocation Scheme for D2D Multicast with QoS Guarantees in Cellular Networks

    Directory of Open Access Journals (Sweden)

    Fangmin Li

    2016-09-01

    Full Text Available Device-to-device (D2D multicast communication can greatly improve the spectrum utilization in a content delivery scenario. However, the co-channel interference and power consumption brought by D2D bring new challenges. All the D2D multicast groups expect to achieve a higher system capacity with less extra energy cost. In this paper, we investigate the uplink resource allocation issue when D2D multicast groups share the resources with other cellular uses (CUs, while guaranteeing a certain level of quality of service (QoS to CUs and D2D users. Firstly we address a flexible tradeoff framework in which the system power consumption and the system capacity (i.e., the number of admitted D2D links are assigned with different weight factors so that these two objectives are jointly considered. Then we propose an efficient resource optimization scheme, which comprises sub-channel allocation and signal-to-interference- plus-noise ratio (SINR assignment. Numerical results validate the effectiveness of the proposed framework, and demonstrate the advantages in dealing with the proposed multi-objective optimization problem.

  7. RECURRENT CROUP IN CHILDREN

    Directory of Open Access Journals (Sweden)

    S. L. Piskunova

    2014-01-01

    Full Text Available The article presents the results of examination of 1849 children, entering children's infectioushospitalofVladivostokwith the clinical picture of croup of viral etiology. The clinical features of primary and recurrent croup are described. Frequency of recurrent croup inVladivostokis 8%. Children with a recurrent croup had the burdened premorbid background, and also persistent herpetic infections (cytomegalic infection in 42,9% cases, cytomegalic infection in combination with the herpes simplex virus -1. Frequency of croups substantially rose in the period of epidemic of influenza.

  8. Accurately Identifying New QoS Violation Driven by High-Distributed Low-Rate Denial of Service Attacks Based on Multiple Observed Features

    Directory of Open Access Journals (Sweden)

    Jian Kang

    2015-01-01

    Full Text Available We propose using multiple observed features of network traffic to identify new high-distributed low-rate quality of services (QoS violation so that detection accuracy may be further improved. For the multiple observed features, we choose F feature in TCP packet header as a microscopic feature and, P feature and D feature of network traffic as macroscopic features. Based on these features, we establish multistream fused hidden Markov model (MF-HMM to detect stealthy low-rate denial of service (LDoS attacks hidden in legitimate network background traffic. In addition, the threshold value is dynamically adjusted by using Kaufman algorithm. Our experiments show that the additive effect of combining multiple features effectively reduces the false-positive rate. The average detection rate of MF-HMM results in a significant 23.39% and 44.64% improvement over typical power spectrum density (PSD algorithm and nonparametric cumulative sum (CUSUM algorithm.

  9. Hybrid resource provisioning for clouds

    International Nuclear Information System (INIS)

    Rahman, Mahfuzur; Graham, Peter

    2012-01-01

    Flexible resource provisioning, the assignment of virtual machines (VMs) to physical machine, is a key requirement for cloud computing. To achieve 'provisioning elasticity', the cloud needs to manage its available resources on demand. A-priori, static, VM provisioning introduces no runtime overhead but fails to deal with unanticipated changes in resource demands. Dynamic provisioning addresses this problem but introduces runtime overhead. To reduce VM management overhead so more useful work can be done and to also avoid sub-optimal provisioning we propose a hybrid approach that combines static and dynamic provisioning. The idea is to adapt a good initial static placement of VMs in response to evolving load characteristics, using live migration, as long as the overhead of doing so is low and the effectiveness is high. When this is no longer so, we trigger a revised static placement. (Thus, we are essentially applying local multi-objective optimization to tune a global optimization with reduced overhead.) This approach requires a complicated migration decision algorithm based on current and predicted:future workloads, power consumptions and memory usage in the host machines as well as network burst characteristics for the various possible VM multiplexings (combinations of VMs on a host). A further challenge is to identify those characteristics of the dynamic provisioning that should trigger static re-provisioning.

  10. Inguinal hernia recurrence: Classification and approach

    Directory of Open Access Journals (Sweden)

    Campanelli Giampiero

    2006-01-01

    Full Text Available The authors reviewed the records of 2,468 operations of groin hernia in 2,350 patients, including 277 recurrent hernias updated to January 2005. The data obtained - evaluating technique, results and complications - were used to propose a simple anatomo-clinical classification into three types which could be used to plan the surgical strategy:Type R1: first recurrence ′high,′ oblique external, reducible hernia with small (< 2 cm defect in non-obese patients, after pure tissue or mesh repairType R2: first recurrence ′low,′ direct, reducible hernia with small (< 2 cm defect in non-obese patients, after pure tissue or mesh repairType R3: all the other recurrences - including femoral recurrences; recurrent groin hernia with big defect (inguinal eventration; multirecurrent hernias; nonreducible, linked with a controlateral primitive or recurrent hernia; and situations compromised from aggravating factors (for example obesity or anyway not easily included in R1 or R2, after pure tissue or mesh repair.

  11. Chemoradiotherapy response in recurrent rectal cancer.

    Science.gov (United States)

    Yu, Stanley K T; Bhangu, Aneel; Tait, Diana M; Tekkis, Paris; Wotherspoon, Andrew; Brown, Gina

    2014-02-01

    The efficacy of response to preoperative chemoradiotherapy (CRT) in recurrent versus primary rectal cancer has not been investigated. We compared radiological downsizing between primary and recurrent rectal cancers following CRT and determined the optimal size reduction threshold for response validated by survival outcomes. The proportional change in tumor length for primary and recurrent rectal cancers following CRT was compared using the independent sample t-test. Overall survival (OS) was calculated using the Kaplan-Meier product limit method and differences between survival for tumor size reduction thresholds of 30% (response evaluation criteria in solid tumors [RECIST]), 40%, and 50% after CRT in primary and recurrent rectal cancer groups. A total of 385 patients undergoing CRT were analyzed, 99 with recurrent rectal cancer and 286 with primary rectal cancer. The mean proportional reduction in maximum craniocaudal length was significantly higher for primary rectal tumors (33%) compared with recurrent rectal cancer (11%) (P rectal cancer when ≤30% or ≤40% definitions were used. However, for both primary and recurrent tumors, significant differences in median 3-year OS were observed when a RECIST cut-off of 50% was used. OS was 99% versus 77% in primary and 100% versus 42% in recurrent rectal cancer (P = 0.002 and P = 0.03, respectively). Only patients that demonstrated >50% size reduction showed a survival benefit. Recurrent rectal cancer appears radioresistant compared with primary tumors for tumor size after CRT. Further investigation into improving/intensifying chemotherapy and radiotherapy for locally recurrent rectal cancer is justified. © 2013 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

  12. Radiotherapy in Locoregional Recurrent Breast Carcinoma

    International Nuclear Information System (INIS)

    Ha, Sung Whan; Yang, Mi Gyoung; Chung, Woong Ki; Park, Charn Il; Bang, Yung Jue; Kim, Noe Kyung; Choe, Kuk Jin

    1988-01-01

    Thirty eight women with recurrent breast carcinoma involving chest wall and/or regional lymph nodes after surgery with or without systemic therapy were treated with radiation between 1979 and 1986. Among them, 5 patients were excluded from analysis because of incomplete treatment. The median follow up of survivors was 30 months (ranged 1-79 months). Fifteen (45%) patients had their disease confined to the chest wall and eighteen patients had lymph node involvement as some of their locoregional recurrent disease. Within 36 months after the initial treatment, 87% of recurrences manifested themselves. All patients had radiotherapy to at least the site of involvement. In 8 patients, recurrent tumors were treated with complete excision followed by radiation. Of the remaining 25 patients, 18(72%) had complete response (CR) following radiotherapy. The actuarial 3-year survival of all patients following locoregional recurrence was 50%. Three year survival was 24% in those 25 patients who had recurrences within 24 months of the initial treatment. For those 8 patients whose recurrences occurred after more than 24 month disease free interval, the 3-year survival was 100%. For those patients with recurrences confined to chest wall alone, 3-year survival was 57%. The patients who had lymph node involvement as part of their locoregional recurrences had a 43% 3-year survival. The majority of them developed distant metastases. Those patients who had a CR showed 63% 3-year survival. On the other hand, 1 year survival was only 33% for those patients who had a less than CR. Three patients developed carcinoma of the contralateral breast following radiotherapy. Three year survival following locoregional recurrence was 40% for patients whose initial treatment for their primary breast carcinoma was surgery and adjuvant systemic therapy. For those patients whose primary breast carcinoma was treated by surgery alone, the 3-year survival following locoregional recurrence was 71%. In

  13. Treatment of locally recurrent rectal cancer

    International Nuclear Information System (INIS)

    Kococik, Z.; Kococik, M.

    2007-01-01

    The suggested classifications of locally recurrent rectal cancer are based on the presence of symptoms and the degree of tumour fixation to the pelvic wall, or, otherwise, account for factor T in the TMN system. Although the results of rectal cancer treatment have improved, which may be attributed to total meso rectal excision and application of perioperative radiotherapy and radiochemotherapy, the ratio of cases of locally recurrent rectal cancer still amount from several to over a dozen percent. Among the available diagnostic methods for detecting locally recurrent rectal cancer after anterior rectal resection, endorectal sonography is of special importance. In the estimation of prognostic factors the lack of vascular invasion in recurrent cancer and the long period between the treatment of primary rectal cancer and the development of recurrence are a sign of good prognosis, while pain prior to recurrence treatment and male sex diminish the chances for cure. Locally recurrent rectal cancer impairs the patient's quality of life in all measurable aspects, but even after complete recovery we observe severe disturbances of sexual activity in most patients, and a number of patients require hygiene pads or suffer from chronic pain. Local recurrence of rectal cancer is more commonly qualified for excision after surgical treatment only, than after preoperative radiotherapy. The probability of total recurrent rectal cancer excision increases when the patient is younger, the primary tumours was less advanced and the first operation was sphincter-sparing surgery. Progress in the surgical treatment of recurrent rectal cancer was brought on by the introduction of the composite musculocutaneous flap to compensate the loss of perineal tissue. The application of intraoperative radiotherapy improves treatment results of recurrent rectal cancer, however at the cost of more frequent, serious postoperative complications and intense pain. In inoperable cases high dose regional

  14. Recurrent Respiratory Papillomatosis or Laryngeal Papillomatosis

    Science.gov (United States)

    ... Home » Health Info » Voice, Speech, and Language Recurrent Respiratory Papillomatosis or Laryngeal Papillomatosis On this page: What ... find additional information about RRP? What is recurrent respiratory papillomatosis? Recurrent respiratory papillomatosis (RRP) is a disease ...

  15. 12 CFR 714.8 - Are the early payment provisions, or interest rate provisions, applicable in leasing arrangements?

    Science.gov (United States)

    2010-01-01

    ... provisions, or interest rate provisions, applicable in leasing arrangements? You are not subject to the early... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Are the early payment provisions, or interest rate provisions, applicable in leasing arrangements? 714.8 Section 714.8 Banks and Banking NATIONAL...

  16. Recurrent Kawasaki disease, United States and Japan

    Science.gov (United States)

    Maddox, Ryan A.; Holman, Robert C.; Uehara, Ritei; Callinan, Laura S.; Guest, Jodie L.; Schonberger, Lawrence B.; Nakamura, Yosikazu; Yashiro, Mayumi; Belay, Ermias D.

    2015-01-01

    Background Descriptive epidemiologic studies of recurrent and non-recurrent Kawasaki disease (KD) may identify other potentially important differences between these illnesses. Methods Data from the United States and Japan, the Centers for Disease Control and Prevention (CDC) national KD surveillance (1984–2008) and the 17th Japanese nationwide survey (2001–2002), respectively, were analyzed to examine recurrent KD patients <18 years of age meeting the CDC KD case or atypical KD case definition. These patients were compared to non-recurrent KD patients. Results Of the 5557 US KD patients <18 years of age during 1984–2008, 97 (1.7%) were identified as having had recurrent KD. Among the US Asian/Pacific Islander KD patients, 3.5% had recurrent KD, which was similar to the percentage identified among KD patients (3.5%) in the Japanese survey. Compared to non-recurrent KD patients, KD patients experiencing a recurrent KD episode were more likely to be older, fulfill the atypical KD case definition, and have coronary artery abnormalities (CAA) despite IVIG treatment. Conclusions Differences in the age, race, and frequency of CAA exist between recurrent and non-recurrent KD patients. The increased association of CAA with recurrent KD suggests that more aggressive treatment strategies in conjunction with IVIG may be indicated for the second episode of KD. PMID:26096590

  17. Recurrent rates and risk factors associated with recurrent painful bullous keratopathy after primary phototherapeutic keratectomy

    Directory of Open Access Journals (Sweden)

    Kasetsuwan N

    2015-09-01

    Full Text Available Ngamjit Kasetsuwan, Kanokorn Sakpisuttivanit, Usanee Reinprayoon, Vilavun Puangsricharern Department of Ophthalmology, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Bangkok, Thailand Objective: To assess the recurrent rate, mean survival time, and risk factors associated with recurrent painful bullous keratopathy (BK after primary treatment with phototherapeutic keratectomy.Methods: Medical records from 72 patients (72 eyes who had phototherapeutic keratectomy for painful BK were evaluated. Data for sex, age, duration of BK, associated ocular and systemic diseases (hypertension, diabetes mellitus, ischemic heart disease, asthma, dyslipidemia, and rheumatoid arthritis, frequency and degree of pain (grade 1–3, visual acuity, corneal thickness, intraocular pressure, and laser setting were extracted and analyzed.Results: The mean age of the patients was 64.2±11.4 years. The mean preoperative duration of BK was 15.0±11.0 months. Most patients had pseudophakic BK (69.40%. Majority of the cases had grade 3 degree of pain (48.60%. Glaucoma and hypertension were markedly found among these patients (51.40% and 19.40%, respectively. Preoperative mean intraocular pressure and corneal thickness were 13.70±4.95 mmHg and 734.1±83.80 µm, respectively. The mean laser diameter and depth were 8.36±1.22 mm and 38.89±8.81 µm, respectively. Systemic disease was significantly associated with the risk for developing recurrent painful BK (P=0.022, hazard ratio [HR] 1.673, 95% confidence interval [CI] 1.08–2.58. The overall recurrent rate was 51%. The average duration time of recurrent painful BK was 17.3±12.9 months (range 1–50 months. The median survival time before recurrence was 29.0±6.6 months.Conclusion: Systemic disease was found to be the only risk factor significantly associated with the development of recurrent painful BK. Low recurrent rate and long mean survival time showed that phototherapeutic

  18. Recurrence of anxiety disorders and its predictors

    NARCIS (Netherlands)

    Scholten, Willemijn D.; Batelaan, Neeltje M.; van Balkom, Anton J. L. M.; Penninx, Brenda; Smit, Johannes H.; van Oppen, Patricia

    Background: The chronic course of anxiety disorders and its high burden of disease are partly due to the recurrence of anxiety disorders after remission. However, knowledge about recurrence rates and predictors of recurrence is scarce. This article reports on recurrence rates of anxiety disorders

  19. Recurrence of anxiety disorders and its predictors

    NARCIS (Netherlands)

    Scholten, W.D.; Batelaan, N.M.; van Balkom, A.J.L.M.; Penninx, B.W.J.H.; Smit, J.H.; van Oppen, P.

    2013-01-01

    Background: The chronic course of anxiety disorders and its high burden of disease are partly due to the recurrence of anxiety disorders after remission. However, knowledge about recurrence rates and predictors of recurrence is scarce. This article reports on recurrence rates of anxiety disorders

  20. Recurrence of non-Hodgkin's lymphoma

    International Nuclear Information System (INIS)

    Watanabe, Toshikazu; Kiyono, Kunihiro; Niibe, Hideo; Horiuchi, Junichi; Kaneta, Koichi; Morita, Kozo; Masaki, Norie; Hayabuchi, Naofumi.

    1988-01-01

    563 patients with Stage I and II non-Hodgkin's lymphoma were treated by radiotherapy. 34 recurrences that occured after 3 years from initial treatment were seen in those patients. 15 (44 %) of 34 recurrences occured after 5 years. 20 patients (59 %) had remission by re-treatment, and 13 (38 %) survived more than 2 years. 20 (59 %) of recurrences were seen on head and neck lesions and superficial lymph nodes. (author)

  1. 50 CFR 71.12 - General provisions.

    Science.gov (United States)

    2010-10-01

    ....12 General provisions. The following provisions shall apply to public sport fishing on a national... fish hatchery area. (e) Each person shall comply with the provisions of any special notices governing...

  2. Vocal fold hemorrhage: factors predicting recurrence.

    Science.gov (United States)

    Lennon, Christen J; Murry, Thomas; Sulica, Lucian

    2014-01-01

    Vocal fold hemorrhage is an acute phonotraumatic injury treated with voice rest; recurrence is a generally accepted indication for surgical intervention. This study aims to identify factors predictive of recurrence based on outcomes of a large clinical series. Retrospective cohort. Retrospective review of cases of vocal fold hemorrhage presenting to a university laryngology service. Demographic information was compiled. Videostroboscopic exams were evaluated for hemorrhage extent, presence of varix, mucosal lesion, and/or vocal fold paresis. Vocal fold hemorrhage recurrence was the main outcome measure. Follow-up telephone survey was used to complement clinical data. Forty-seven instances of vocal fold hemorrhage were evaluated (25M:22F; 32 professional voice users). Twelve of the 47 (26%) patients experienced recurrence. Only the presence of varix demonstrated significant association with recurrence (P = 0.0089) on multivariate logistic regression. Vocal fold hemorrhage recurred in approximately 26% of patients. Varix was a predictor of recurrence, with 48% of those with varix experiencing recurrence. Monitoring, behavioral management and/or surgical intervention may be indicated to treat patients with such characteristics. © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

  3. Recurrent endometrial cancer: patterns of recurrent disease and assessment of prognosis

    Energy Technology Data Exchange (ETDEWEB)

    Sohaib, S.A. [Department of Radiology, Royal Marsden Hospital, London (United Kingdom); Houghton, S.L. [Department of Radiology, Royal Marsden Hospital, London (United Kingdom); Meroni, R. [Department of Academic Radiology, St Bartholomew' s Hospital, London (United Kingdom); Rockall, A.G. [Department of Academic Radiology, St Bartholomew' s Hospital, London (United Kingdom); Blake, P. [Department of Gynaecological Oncology, Royal Marsden Hospital, London (United Kingdom); Reznek, R.H. [Department of Academic Radiology, St Bartholomew' s Hospital, London (United Kingdom)

    2007-01-15

    Aim: To evaluate patterns of disease and identify factors predicting outcome in patients presenting with recurrent endometrial adenocarcinoma following primary surgery. Materials and methods: A retrospective review was performed of the imaging and clinical data in 86 patients (median age 66 years, range 42-88 years) presenting with recurrent endometrial adenocarcinoma following primary surgery. Results: Following primary surgery recurrent disease occurred within 2 years in 64% and within 3 years in 87%. Relapse was seen within lymph nodes in 41 (46%), the vagina in 36 (42%) the peritoneum in 24 (28%) and the lung in 21 (24%). Unusual sites of disease included spleen, pancreas, rectum, muscle and brain. Univariate survival analysis showed the factors significant for poor outcome were: multiple sites of disease, liver and splenic disease, haematogenous, peritoneal and nodal spread, poorly differentiated tumour, and early relapse. The presence of disease within the vagina, bladder or lung was not associated with poor prognosis. Multivariate analysis identified multiple sites of disease, liver and splenic metastases to be independent predictors of poor outcome. Conclusion: The most frequently observed sites of relapse are: lymph nodes, vagina, peritoneum and lung. Significant predictors of poor outcome in recurrent disease are multiple sites of disease and liver and splenic metastases.

  4. Survey on Wireless Sensor Network Technologies for Industrial Automation: The Security and Quality of Service Perspectives

    Directory of Open Access Journals (Sweden)

    Delphine Christin

    2010-04-01

    Full Text Available Wireless Sensor Networks (WSNs are gradually adopted in the industrial world due to their advantages over wired networks. In addition to saving cabling costs, WSNs widen the realm of environments feasible for monitoring. They thus add sensing and acting capabilities to objects in the physical world and allow for communication among these objects or with services in the future Internet. However, the acceptance of WSNs by the industrial automation community is impeded by open issues, such as security guarantees and provision of Quality of Service (QoS. To examine both of these perspectives, we select and survey relevant WSN technologies dedicated to industrial automation. We determine QoS requirements and carry out a threat analysis, which act as basis of our evaluation of the current state-of-the-art. According to the results of this evaluation, we identify and discuss open research issues.

  5. 14 CFR 121.427 - Recurrent training.

    Science.gov (United States)

    2010-01-01

    ... procedures set forth in the certificate holder's approved low-altitude windshear flight training program and... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Recurrent training. 121.427 Section 121.427..., FLAG, AND SUPPLEMENTAL OPERATIONS Training Program § 121.427 Recurrent training. (a) Recurrent training...

  6. Coordinated Multi-layer Multi-domain Optical Network (COMMON) for Large-Scale Science Applications (COMMON)

    Energy Technology Data Exchange (ETDEWEB)

    Vokkarane, Vinod [University of Massachusetts

    2013-09-01

    We intend to implement a Coordinated Multi-layer Multi-domain Optical Network (COMMON) Framework for Large-scale Science Applications. In the COMMON project, specific problems to be addressed include 1) anycast/multicast/manycast request provisioning, 2) deployable OSCARS enhancements, 3) multi-layer, multi-domain quality of service (QoS), and 4) multi-layer, multidomain path survivability. In what follows, we outline the progress in the above categories (Year 1, 2, and 3 deliverables).

  7. Networking Technologies for Future Home Networks Using 60 GHz Radio

    OpenAIRE

    Wang, J.

    2010-01-01

    Networking technologies have been changing the life of people in their private residential space. With the arrival of high definition (HD) multimedia services and broadband communications into the living space, future home networks are expected to support high speed device-to-device connectivity with Quality-of-Service (QoS) provisioning. There is no prize for guessing that it has to be wireless communication which creates maximal freedom. Nevertheless, it is doubtful that today's home networ...

  8. Opioids and breast cancer recurrence

    DEFF Research Database (Denmark)

    Cronin-Fenton, Deirdre P; Heide-Jørgensen, Uffe; Ahern, Thomas P

    2015-01-01

    BACKGROUND: Opioids may alter immune function, thereby potentially affecting cancer recurrence. The authors investigated the association between postdiagnosis opioid use and breast cancer recurrence. METHODS: Patients with incident, early stage breast cancer who were diagnosed during 1996 through...... 2008 in Denmark were identified from the Danish Breast Cancer Cooperative Group Registry. Opioid prescriptions were ascertained from the Danish National Prescription Registry. Follow-up began on the date of primary surgery for breast cancer and continued until breast cancer recurrence, death......, emigration, 10 years, or July 31, 2013, whichever occurred first. Cox regression models were used to compute hazard ratios and 95% confidence intervals associating breast cancer recurrence with opioid prescription use overall and by opioid type and strength, immunosuppressive effect, chronic use (≥6 months...

  9. Risk factors for recurrent spontaneous epistaxis.

    Science.gov (United States)

    Abrich, Victor; Brozek, Annabelle; Boyle, Timothy R; Chyou, Po-Huang; Yale, Steven H

    2014-12-01

    To identify risk factors associated with spontaneous recurrent epistaxis. This was a retrospective cohort study assessing patients in the Marshfield Clinic system diagnosed as having epistaxis between January 1, 1991, and January 1, 2011. There were 461 cases with at least 2 episodes of spontaneous epistaxis within 3 years and 912 controls with only 1 episode in the same time frame. More than 50 potential risk factors were investigated, including demographic features, substance use, nasal anatomical abnormalities, nasal infectious and inflammatory processes, medical comorbidities, medications, and laboratory values. A Cox proportional hazards regression modeling approach was used to calculate hazard ratios of epistaxis recurrence. Traditional risk factors for epistaxis, including nasal perforation, nasal septum deviation, rhinitis, sinusitis, and upper respiratory tract infection, did not increase the risk of recurrence. Significant risk factors for recurrent epistaxis included congestive heart failure, diabetes mellitus, hypertension, and a history of anemia. Warfarin use increased the risk of recurrence, independent of international normalized ratio. Aspirin and clopidogrel were not found to increase the risk of recurrence. Few major adverse cardiovascular events were observed within 30 days of the first epistaxis event. Congestive heart failure is an underappreciated risk factor for recurrent epistaxis. Hypertension and diabetes mellitus may induce atherosclerotic changes in the nasal vessels, making them friable and more at risk for bleeding. Patients with recurrent epistaxis may also be more susceptible to developing anemia. Physicians should promote antiplatelet and antithrombotic medication adherence despite an increased propensity for recurrent epistaxis to prevent major adverse cardiovascular events. Copyright © 2014 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  10. 24 CFR 201.16 - Default provision.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Default provision. 201.16 Section... PROPERTY IMPROVEMENT AND MANUFACTURED HOME LOANS Loan and Note Provisions § 201.16 Default provision. The... default by the borrower. ...

  11. Use of recurrence plot and recurrence quantification analysis in Taiwan unemployment rate time series

    Science.gov (United States)

    Chen, Wei-Shing

    2011-04-01

    The aim of the article is to answer the question if the Taiwan unemployment rate dynamics is generated by a non-linear deterministic dynamic process. This paper applies a recurrence plot and recurrence quantification approach based on the analysis of non-stationary hidden transition patterns of the unemployment rate of Taiwan. The case study uses the time series data of the Taiwan’s unemployment rate during the period from 1978/01 to 2010/06. The results show that recurrence techniques are able to identify various phases in the evolution of unemployment transition in Taiwan.

  12. Convergence

    DEFF Research Database (Denmark)

    Madsen, Ole Brun; Nielsen, Jens Frederik Dalsgaard; Schiøler, Henrik

    2002-01-01

    Convergence trends between the WAN Internet area, characterized by best effort service provision, and the real time LAN domain, with requirements for guaranteed services, are identified and discussed. A bilateral evolution is identified, where typical bulk service applications from WAN, such as m......Convergence trends between the WAN Internet area, characterized by best effort service provision, and the real time LAN domain, with requirements for guaranteed services, are identified and discussed. A bilateral evolution is identified, where typical bulk service applications from WAN...... with the emergence of remote service provision, such as supervision and control of decentralized heating facilities and wind based electrical power production. The reliability issue is addressed from a structural viewpoint, where the concept of Structural QoS (SQoS) is defined to support reliability modelling...

  13. Risk factors of recurrent anal sphincter ruptures

    DEFF Research Database (Denmark)

    Jangö, Hanna; Langhoff-Roos, J; Rosthøj, Steen

    2012-01-01

    Please cite this paper as: Jangö H, Langhoff-Roos J, Rosthøj S, Sakse A. Risk factors of recurrent anal sphincter ruptures: a population-based cohort study. BJOG 2012;00:000-000 DOI: 10.1111/j.1471-0528.2012.03486.x. Objective  To determine the incidence and risk factors of recurrent anal sphincter...... were used to determine risk factors of recurrent ASR. Main outcome measures  The incidence of recurrent ASR and odds ratios for possible risk factors of recurrent ASR: age, body mass index, grade of ASR, birthweight, head circumference, gestational age, presentation, induction of labour, oxytocin...... augmentation, epidural, episiotomy, vacuum extraction, forceps, shoulder dystocia, delivery interval and year of second delivery. Results  Out of 159 446 women, 7336 (4.6%) experienced an ASR at first delivery, and 521 (7.1%) had a recurrent ASR (OR 5.91). The risk factors of recurrent ASR in the multivariate...

  14. Heterogeneous recurrence monitoring and control of nonlinear stochastic processes

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Hui, E-mail: huiyang@usf.edu; Chen, Yun [Complex Systems Monitoring, Modeling and Analysis Laboratory, University of South Florida, Tampa, Florida 33620 (United States)

    2014-03-15

    Recurrence is one of the most common phenomena in natural and engineering systems. Process monitoring of dynamic transitions in nonlinear and nonstationary systems is more concerned with aperiodic recurrences and recurrence variations. However, little has been done to investigate the heterogeneous recurrence variations and link with the objectives of process monitoring and anomaly detection. Notably, nonlinear recurrence methodologies are based on homogeneous recurrences, which treat all recurrence states in the same way as black dots, and non-recurrence is white in recurrence plots. Heterogeneous recurrences are more concerned about the variations of recurrence states in terms of state properties (e.g., values and relative locations) and the evolving dynamics (e.g., sequential state transitions). This paper presents a novel approach of heterogeneous recurrence analysis that utilizes a new fractal representation to delineate heterogeneous recurrence states in multiple scales, including the recurrences of both single states and multi-state sequences. Further, we developed a new set of heterogeneous recurrence quantifiers that are extracted from fractal representation in the transformed space. To that end, we integrated multivariate statistical control charts with heterogeneous recurrence analysis to simultaneously monitor two or more related quantifiers. Experimental results on nonlinear stochastic processes show that the proposed approach not only captures heterogeneous recurrence patterns in the fractal representation but also effectively monitors the changes in the dynamics of a complex system.

  15. Differential diagnosis of recurrent bronchitis in children

    Directory of Open Access Journals (Sweden)

    I. I. Zakirov

    2016-01-01

    Full Text Available The interest of the doctors — pediatricians to recurrent bronchitis is caused by its high specific weight in the structure of bronchopulmonary pathology in children, the complexity and the need to search the differential selection of an individual regimen and prevention. Recurrent bronchitis with bronchoobstructive syndromes patient is regarded as a predictor of asthma, however, erroneously consider these nosological forms as the stages of a single pathophysiological chain as congenital and acquired diseases of respiratory system, pathology of gastro-intestinal tract, cardio-vascular system can masquerade as recurrent bronchitis. The aim of this work — to analyze the current medical literature on the problem of differential search causes leading recurrent respiratory syndrome in children. Materials and methods. The review publications domestic and foreign authors studied data from clinical and epidemiological studies. Results and its discussion. Anatomical physiological characteristics of the respiratory tract, complicated premorbid background, the re-infection of the child respiratory infection contribute to the recurrent course of bronchitis. The most common recurrent bronchitis is transient, recurrent bronchitis episodes completely stoped with the age of the child. Recurrent respiratory infections can fix bronchial hyperreactivity and with the presence of aggravated allergic history lead to the development of asthma. Severe bronchitis, resistance to standard scheme of therapy, the frequent recurrence of respiratory syndrome dictate the need to expand the diagnostic research to clarify the leading cause of recurrent bronchitis. Conclusion. Recurrent bronchitis is considered as a separate nosological form. At the same time, by repeated episodes of respiratory infection may be masked by malformations, hereditary diseases of respiratory system, bronchus foreign body microaspiration syndrome, pathology of the cardio-vascular system. 

  16. Evaluation of Drought Implications on Ecosystem Services: Freshwater Provisioning and Food Provisioning in the Upper Mississippi River Basin.

    Science.gov (United States)

    Li, Ping; Omani, Nina; Chaubey, Indrajeet; Wei, Xiaomei

    2017-05-08

    Drought is one of the most widespread extreme climate events with a potential to alter freshwater availability and related ecosystem services. Given the interconnectedness between freshwater availability and many ecosystem services, including food provisioning, it is important to evaluate the drought implications on freshwater provisioning and food provisioning services. Studies about drought implications on streamflow, nutrient loads, and crop yields have been increased and these variables are all process-based model outputs that could represent ecosystem functions that contribute to the ecosystem services. However, few studies evaluate drought effects on ecosystem services such as freshwater and food provisioning and quantify these services using an index-based ecosystem service approach. In this study, the drought implications on freshwater and food provisioning services were evaluated for 14 four-digit HUC (Hydrological Unit Codes) subbasins in the Upper Mississippi River Basin (UMRB), using three drought indices: standardized precipitation index ( SPI ), standardized soil water content index ( SSWI ), and standardized streamflow index ( SSI ). The results showed that the seasonal freshwater provisioning was highly affected by the precipitation deficits and/or surpluses in summer and autumn. A greater importance of hydrological drought than meteorological drought implications on freshwater provisioning was evident for the majority of the subbasins, as evidenced by higher correlations between freshwater provisioning and SSI 12 than SPI 12. Food provisioning was substantially affected by the precipitation and soil water deficits during summer and early autumn, with relatively less effect observed in winter. A greater importance of agricultural drought effects on food provisioning was evident for most of the subbasins during crop reproductive stages. Results from this study may provide insights to help make effective land management decisions in responding to

  17. Coping with Fear of Recurrence

    Science.gov (United States)

    ... What Comes Next After Finishing Treatment Coping With Fear of Recurrence Having a Baby After Cancer: Pregnancy ... treatment and preparing for the future. Coping With Fear of Recurrence Learn ways to manage the fear ...

  18. Recurrence relations for spin foam vertices

    International Nuclear Information System (INIS)

    Bonzom, Valentin; Livine, Etera R; Speziale, Simone

    2010-01-01

    We study recurrence relations for various Wigner 3nj-symbols and the non-topological 10j-symbol. For the 6j- and the 15j-symbols which correspond to basic amplitudes of 3d and 4d topological spin foam models, recurrence relations are obtained from the invariance under Pachner moves and can be interpreted as quantizations of the constraints of the underlying classical field theories. We also derive recurrences from the action of holonomy operators on spin network functionals, making a more precise link between the topological Pachner moves and the classical constraints. Interestingly, our recurrence relations apply to any SU(2) invariant symbol, depending on the cycles of the corresponding spin network graph. Another method is used for non-topological objects such as the 10j-symbol and pseudo-isosceles 6j-symbols. The recurrence relations are also interpreted in terms of elementary geometric properties. Finally, we discuss the extension of the recurrences to take into account boundary states which leads to equations similar to Ward identities for correlation functions in the Barrett-Crane model.

  19. Mondini dysplasia with recurrent meningitis.

    Science.gov (United States)

    Lu, M Y; Lee, P I; Lee, C Y; Hsu, C J

    1996-01-01

    Mondini dysplasia is a congenital malformation of the inner ear, commonly associated with hearing impairment, cerebrospinal fluid otorrhea/rhinorrhea and recurrent meningitis. Two such cases are described, with hearing impairment, cerebrospinal fluid rhinorrhea, and several episodes of meningitis. Diagnosis was confirmed by high-resolution computed tomography. After surgical correction of the malformation, there was no recurrent episode of meningitis at subsequent follow-up. To avoid the suffering and the sequelae of recurrent meningitis, an early diagnosis and prompt surgical intervention are crucial for such patients.

  20. 78 FR 18960 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; General Provisions for Domestic...

    Science.gov (United States)

    2013-03-28

    ... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration RIN 0648-XC586 Atlantic Coastal Fisheries Cooperative Management Act Provisions; General Provisions for Domestic Fisheries; Application for Exempted Fishing Permits AGENCY: National Marine Fisheries Service (NMFS), National Oceanic...

  1. Recurrent atrial myxoma.

    Science.gov (United States)

    Macarie, C; Stoica, E; Chioncel, O; Carp, A; Gherghiceanu, D; Stiru, O; Zarma, L; Herlea, V

    2004-01-01

    We have chosen this case of sporadic atrial myxoma for our presentation because it had a particular evolution, with recurrence at 8 years after surgical excision (echocardiography was performed every year) and a particular diagnostic means - at echocardiographic follow-up, the patient being asymptomatic. This presentation, together with a review of literature included in the article, emphasizes the importance of a careful postoperative follow-up of the patients and the existence of some particular aspects of the evolution and symptomatology of recurrent atrial myxoma.

  2. Can recurrence networks show small-world property?

    International Nuclear Information System (INIS)

    Jacob, Rinku; Harikrishnan, K.P.; Misra, R.; Ambika, G.

    2016-01-01

    Recurrence networks are complex networks, constructed from time series data, having several practical applications. Though their properties when constructed with the threshold value ϵ chosen at or just above the percolation threshold of the network are quite well understood, what happens as the threshold increases beyond the usual operational window is still not clear from a complex network perspective. The present Letter is focused mainly on the network properties at intermediate-to-large values of the recurrence threshold, for which no systematic study has been performed so far. We argue, with numerical support, that recurrence networks constructed from chaotic attractors with ϵ equal to the usual recurrence threshold or slightly above cannot, in general, show small-world property. However, if the threshold is further increased, the recurrence network topology initially changes to a small-world structure and finally to that of a classical random graph as the threshold approaches the size of the strange attractor. - Highlights: • Properties of recurrence networks at intermediate-to-large values of recurrence threshold are analyzed from a complex network perspective. • Using a combined plot of characteristic path length and clustering coefficient, it is shown that the recurrence network constructed with recurrence threshold equal to or just above the percolation threshold cannot, in general, display small-world property. • As the recurrence threshold is increased from its usual operational window, the resulting network makes a smooth transition initially to a small-world network for an intermediate range of thresholds and finally to the classical random graph as the threshold becomes comparable to the size of the attractor.

  3. Can recurrence networks show small-world property?

    Energy Technology Data Exchange (ETDEWEB)

    Jacob, Rinku, E-mail: rinku.jacob.vallanat@gmail.com [Department of Physics, The Cochin College, Cochin, 682002 (India); Harikrishnan, K.P., E-mail: kp_hk2002@yahoo.co.in [Department of Physics, The Cochin College, Cochin, 682002 (India); Misra, R., E-mail: rmisra@iucaa.in [Inter University Centre for Astronomy and Astrophysics, Pune, 411007 (India); Ambika, G., E-mail: g.ambika@iiserpune.ac.in [Indian Institute of Science Education and Research, Pune, 411008 (India)

    2016-08-12

    Recurrence networks are complex networks, constructed from time series data, having several practical applications. Though their properties when constructed with the threshold value ϵ chosen at or just above the percolation threshold of the network are quite well understood, what happens as the threshold increases beyond the usual operational window is still not clear from a complex network perspective. The present Letter is focused mainly on the network properties at intermediate-to-large values of the recurrence threshold, for which no systematic study has been performed so far. We argue, with numerical support, that recurrence networks constructed from chaotic attractors with ϵ equal to the usual recurrence threshold or slightly above cannot, in general, show small-world property. However, if the threshold is further increased, the recurrence network topology initially changes to a small-world structure and finally to that of a classical random graph as the threshold approaches the size of the strange attractor. - Highlights: • Properties of recurrence networks at intermediate-to-large values of recurrence threshold are analyzed from a complex network perspective. • Using a combined plot of characteristic path length and clustering coefficient, it is shown that the recurrence network constructed with recurrence threshold equal to or just above the percolation threshold cannot, in general, display small-world property. • As the recurrence threshold is increased from its usual operational window, the resulting network makes a smooth transition initially to a small-world network for an intermediate range of thresholds and finally to the classical random graph as the threshold becomes comparable to the size of the attractor.

  4. Patients at high risk of tuberculosis recurrence.

    Science.gov (United States)

    Mirsaeidi, Mehdi; Sadikot, Ruxana T

    2018-01-01

    Recurrent tuberculosis (TB) continues to be a significant problem and is an important indicator of the effectiveness of TB control. Recurrence can occur by relapse or exogenous reinfection. Recurrence of TB is still a major problem in high-burden countries, where there is lack of resources and no special attention is being given to this issue. The rate of recurrence is highly variable and has been estimated to range from 4.9% to 47%. This variability is related to differences in regional epidemiology of recurrence and differences in the definitions used by the TB control programs. In addition to treatment failure from noncompliance, there are several key host factors that are associated with high rates of recurrence. The widely recognized host factors independent of treatment program that predispose to TB recurrence include gender differences, malnutrition; comorbidities such as diabetes, renal failure, and systemic diseases, especially immunosuppressive states such as human immunodeficiency virus; substance abuse; and environmental exposures such as silicosis. With improved understanding of the human genome, proteome, and metabolome, additional host-specific factors that predispose to recurrence are being identified. Information on temporal and geographical trends of TB cases as well as studies with whole-genome sequencing might provide further information to enable us to fully understand TB recurrence and discriminate between reactivation and new infection. The recently launched World Health Organization End TB Strategy emphasizes the importance of integrated, patient-centered TB care. Continued improvement in diagnosis, treatment approaches, and an understanding of host-specific factors are needed to fully understand the clinical epidemiological and social determinants of TB recurrence.

  5. Recurrent pregnancy loss: current perspectives

    Directory of Open Access Journals (Sweden)

    El Hachem H

    2017-05-01

    Full Text Available Hady El Hachem,1,2 Vincent Crepaux,3 Pascale May-Panloup,4 Philippe Descamps,3 Guillaume Legendre,3 Pierre-Emmanuel Bouet3 1Department of Reproductive Medicine, Ovo Clinic, Montréal, QC, Canada; 2Department of Obstetrics and Gynecology, University of Montreal, Montréal, QC, Canada; 3Department of Obstetrics and Gynecology, Angers University Hopsital, Angers, France; 4Department of Reproductive Biology, Angers University Hospital, Angers, France Abstract: Recurrent pregnancy loss is an important reproductive health issue, affecting 2%–5% of couples. Common established causes include uterine anomalies, antiphospholipid syndrome, hormonal and metabolic disorders, and cytogenetic abnormalities. Other etiologies have been proposed but are still considered controversial, such as chronic endometritis, inherited thrombophilias, luteal phase deficiency, and high sperm DNA fragmentation levels. Over the years, evidence-based treatments such as surgical correction of uterine anomalies or aspirin and heparin for antiphospholipid syndrome have improved the outcomes for couples with recurrent pregnancy loss. However, almost half of the cases remain unexplained and are empirically treated using progesterone supplementation, anticoagulation, and/or immunomodulatory treatments. Regardless of the cause, the long-term prognosis of couples with recurrent pregnancy loss is good, and most eventually achieve a healthy live birth. However, multiple pregnancy losses can have a significant psychological toll on affected couples, and many efforts are being made to improve treatments and decrease the time needed to achieve a successful pregnancy. This article reviews the established and controversial etiologies, and the recommended therapeutic strategies, with a special focus on unexplained recurrent pregnancy losses and the empiric treatments used nowadays. It also discusses the current role of preimplantation genetic testing in the management of recurrent pregnancy

  6. Enhancing end-to-end QoS for multimedia streaming in IMS-based networks

    NARCIS (Netherlands)

    Ozcelebi, T.; Radovanovic, I.; Chaudron, M.R.V.

    2007-01-01

    Convergence of the emerging IP Multimedia Subsystem(IMS) includes unlicensed, nondedicated and nondeterministic hence uncontrollable. computer access, networks for IP multimedia services. It enables provision of resource demanding real-time services and multimedia communication raising new

  7. Patients at high risk of tuberculosis recurrence

    Directory of Open Access Journals (Sweden)

    Mehdi Mirsaeidi

    2018-01-01

    Full Text Available Recurrent tuberculosis (TB continues to be a significant problem and is an important indicator of the effectiveness of TB control. Recurrence can occur by relapse or exogenous reinfection. Recurrence of TB is still a major problem in high-burden countries, where there is lack of resources and no special attention is being given to this issue. The rate of recurrence is highly variable and has been estimated to range from 4.9% to 47%. This variability is related to differences in regional epidemiology of recurrence and differences in the definitions used by the TB control programs. In addition to treatment failure from noncompliance, there are several key host factors that are associated with high rates of recurrence. The widely recognized host factors independent of treatment program that predispose to TB recurrence include gender differences, malnutrition; comorbidities such as diabetes, renal failure, and systemic diseases, especially immunosuppressive states such as human immunodeficiency virus; substance abuse; and environmental exposures such as silicosis. With improved understanding of the human genome, proteome, and metabolome, additional host-specific factors that predispose to recurrence are being identified. Information on temporal and geographical trends of TB cases as well as studies with whole-genome sequencing might provide further information to enable us to fully understand TB recurrence and discriminate between reactivation and new infection. The recently launched World Health Organization End TB Strategy emphasizes the importance of integrated, patient-centered TB care. Continued improvement in diagnosis, treatment approaches, and an understanding of host-specific factors are needed to fully understand the clinical epidemiological and social determinants of TB recurrence.

  8. Young patient's age determines pterygium recurrence after surgery.

    African Journals Online (AJOL)

    2014-03-01

    Mar 1, 2014 ... and degree of fleshiness, and laterality were compared between recurrent and no recurrent pterygia. ... was performed to determine the predictors of pterygium recurrence. Recurrence rates after surgery were compared between. CAT and LCAT. Results. ... obstruction of vision, disfigurement, or frequent.

  9. Recurrence and Relapse in Bipolar Mood Disorder

    Directory of Open Access Journals (Sweden)

    S Gh Mousavi

    2004-06-01

    Full Text Available Background: Despite the effectiveness of pharmacotherapy in acute phase of bipolar mood disorder, patients often experience relapses or recurrent episodes. Hospitalization of patients need a great deal of financial and humanistic resources which can be saved through understanding more about the rate of relapse and factors affecting this rate. Methods: In a descriptive analytical study, 380 patients with bipolar disorder who were hospitalized in psychiatric emergency ward of Noor hospital, Isfahan, Iran, were followed. Each patient was considered for; the frequency of relapse and recurrence, kind of pharmachotherapy, presence of psychotherapeutic treatments, frequency of visits by psychiatrist and the rank of present episode. Results: The overall prevalence of recurrence was 42.2%. Recurrence was lower in patients using lithium carbonate or sodium valproate or combined therapy (about 40%, compared to those using carbamazepine (80%. Recurrence was higher in patients treated with only pharmacotherapy (44.5% compared to those treated with both pharmacotherapy and psychotherapy (22.2%. Patients who were visited monthy by psychiatrist had lower rate of recurrence compared to those who had irregular visits. Conclusion: The higher rate of recurrence observed in carbamazepine therapy may be due to its adverse reactions and consequently poor compliance to this drug. Lower rates of recurrence with psychotherapy and regular visits may be related to the preventive effects of these procedures and especially to the effective management of stress. Keywords: Bipolar Mood Disorder, Recurrence, Relapse.

  10. Recurrence interval analysis of trading volumes.

    Science.gov (United States)

    Ren, Fei; Zhou, Wei-Xing

    2010-06-01

    We study the statistical properties of the recurrence intervals τ between successive trading volumes exceeding a certain threshold q. The recurrence interval analysis is carried out for the 20 liquid Chinese stocks covering a period from January 2000 to May 2009, and two Chinese indices from January 2003 to April 2009. Similar to the recurrence interval distribution of the price returns, the tail of the recurrence interval distribution of the trading volumes follows a power-law scaling, and the results are verified by the goodness-of-fit tests using the Kolmogorov-Smirnov (KS) statistic, the weighted KS statistic and the Cramér-von Mises criterion. The measurements of the conditional probability distribution and the detrended fluctuation function show that both short-term and long-term memory effects exist in the recurrence intervals between trading volumes. We further study the relationship between trading volumes and price returns based on the recurrence interval analysis method. It is found that large trading volumes are more likely to occur following large price returns, and the comovement between trading volumes and price returns is more pronounced for large trading volumes.

  11. Personality predicts recurrence of late-life depression.

    Science.gov (United States)

    Steunenberg, Bas; Beekman, Aartjan T F; Deeg, Dorly J H; Kerkhof, Ad J F M

    2010-06-01

    To examine the association of personality with recurrence of depression in later life. A subsample of 91 subjects from the Longitudinal Aging Study Amsterdam (LASA; baseline sample size n=3107; aged > or = 55 years) depressed at baseline, who had recovered in the course of three years (first follow-up cycle) was identified. 41 (45%) respondents experienced a recurrence during the subsequent six years. The influences of personality and late life stress (demographic factors, health and social factors) on recurrence were investigated prospectively. Recurrence of depression was associated with a high level of neuroticism and low level of mastery, residual depressive symptoms at time of recovery, female gender, pain complaints and feelings of loneliness. In multivariable analysis entering all predictors significant in single variable analysis, residual depressive symptoms and lack of mastery remained significantly associated with recurrence. In predicting the recurrence of depression in later life, the direct effects of personality remain important and comparable in strength with other late life stressors related to recurrence. Copyright 2009 Elsevier B.V. All rights reserved.

  12. MDX-010 in Treating Patients With Recurrent or Refractory Lymphoma

    Science.gov (United States)

    2014-05-22

    Adult Grade III Lymphomatoid Granulomatosis; B-cell Chronic Lymphocytic Leukemia; Cutaneous B-cell Non-Hodgkin Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Intraocular Lymphoma; Nodal Marginal Zone B-cell Lymphoma; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Refractory Hairy Cell Leukemia; Small Intestine Lymphoma; Splenic Marginal Zone Lymphoma; Testicular Lymphoma; Waldenström Macroglobulinemia

  13. A Client-Server System for Ubiquitous Video Service

    Directory of Open Access Journals (Sweden)

    Ronit Nossenson

    2012-12-01

    Full Text Available In this work we introduce a simple client-server system architecture and algorithms for ubiquitous live video and VOD service support. The main features of the system are: efficient usage of network resources, emphasis on user personalization, and ease of implementation. The system supports many continuous service requirements such as QoS provision, user mobility between networks and between different communication devices, and simultaneous usage of a device by a number of users.

  14. Investigation on feasibility of recurrence quantification analysis for ...

    African Journals Online (AJOL)

    The RQA parameters such as percent recurrence (REC), trapping time (TT), percent laminarity (LAM) and entropy (ENT), and also the recurrence plots color patterns for different flank wear, can be used in detecting insert wear in face milling. Keywords: milling, flank wear, recurrence plot, recurrence quantification analysis.

  15. Recurrent IVF failure and hereditary thrombophilia.

    Science.gov (United States)

    Safdarian, Leila; Najmi, Zahra; Aleyasin, Ashraf; Aghahosseini, Marzieh; Rashidi, Mandana; Asadollah, Sara

    2014-07-01

    The largest percentage of failed invitro fertilization (IVF (cycles, are due to lack of implantation. As hereditary thrombophilia can cause in placentation failure, it may have a role in recurrent IVF failure. Aim of this case-control study was to determine whether hereditary thrombophilia is more prevalent in women with recurrent IVF failures. Case group comprised 96 infertile women, with a history of recurrent IVF failure. Control group was comprised of 95 healthy women with proven fertility who had conceived spontaneously. All participants were assessed for the presence of inherited thrombophilias including: factor V Leiden, methilen tetrahydrofolate reductase (MTHFR) mutation, prothrombin mutation, homocystein level, protein S and C deficiency, antithrombin III (AT-III) deficiency and plasminogen activator inhibitor-1 (PAI-1) mutation. Presence of thrombophilia was compared between groups. Having at least one thrombophilia known as a risk factor for recurrent IVF failure (95% CI=1.74-5.70, OR=3.15, p=0.00). Mutation of factor V Leiden (95% CI=1.26-10.27, OR=3.06, P=0.01) and homozygote form of MTHFR mutation (95% CI=1.55-97.86, OR=12.33, p=0.05) were also risk factors for recurrent IVF failure. However, we could not find significant difference in other inherited thrombophilia's. Inherited thrombophilia is more prevalent in women with recurrent IVF failure compared with healthy women. Having at least one thrombophilia, mutation of factor V Leiden and homozygote form of MTHFR mutation were risk factors for recurrent IVF failure.

  16. Decidability of uniform recurrence of morphic sequences

    OpenAIRE

    Durand , Fabien

    2012-01-01

    We prove that the uniform recurrence of morphic sequences is decidable. For this we show that the number of derived sequences of uniformly recurrent morphic sequences is bounded. As a corollary we obtain that uniformly recurrent morphic sequences are primitive substitutive sequences.

  17. Recurrence of amblyopia after occlusion therapy.

    Science.gov (United States)

    Bhola, Rahul; Keech, Ronald V; Kutschke, Pamela; Pfeifer, Wanda; Scott, William E

    2006-11-01

    To determine the stability of visual acuity (VA) after a standardized occlusion regimen in children with strabismic and/or anisometropic amblyopia. Retrospective, population-based, consecutive observational case series. Four hundred forty-nine patients younger than 10 years who underwent an occlusion trial for amblyopia and were observed until there was a recurrence of amblyopia or for a maximum of 1 year after decrease or cessation of occlusion therapy. We performed a retrospective chart review of all patients treated by occlusion therapy for strabismic and/or anisometropic amblyopia at our institution over a 34-year period. Of the 1621 patients identified in our database, 449 met the eligibility criteria and were included in this study. Patients having at least a 2 logarithm of the minimum angle of resolution (logMAR)-level improvement in VA by optotypes or a change from unmaintained to maintained fixation preference during the course of occlusion therapy were included. A recurrence of amblyopia was defined as > or =2 logMAR levels of VA reduction or reversal of fixation preference within 1 year after a decrease or cessation of occlusion therapy. Recurrence of amblyopia after a decrease or cessation of occlusion therapy and its relationship with patient age and VA of the amblyopic eye at the time of decrease or cessation of occlusion therapy. Of 653 occlusion trials, 179 (27%) resulted in recurrence of amblyopia. The recurrence was found to be inversely correlated with patient age. There was no statistically significant association between the recurrence of amblyopia and VA of the amblyopic eye at the end of maximal occlusion therapy. There is a clinically important risk of amblyopia recurrence when occlusion therapy is decreased before the age of 10 years. The risk of recurrence is inversely correlated with age (P<0.0001).

  18. Stereological analysis of nuclear volume in recurrent meningiomas

    DEFF Research Database (Denmark)

    Madsen, C; Schrøder, H D

    1994-01-01

    A stereological estimation of nuclear volume in recurrent and non-recurrent meningiomas was made. The aim was to investigate whether this method could discriminate between these two groups. We found that the mean nuclear volumes in recurrent meningiomas were all larger at debut than in any...... of the control tumors. The mean nuclear volume of the individual recurrent tumors appeared to change with time, showing a tendency to diminish. A relationship between large nuclear volume at presentation and number of or time interval between recurrences was not found. We conclude that measurement of mean...... nuclear volume in meningiomas might help identify a group at risk of recurrence....

  19. Recurrence determinism and Li-Yorke chaos for interval maps

    OpenAIRE

    Špitalský, Vladimír

    2017-01-01

    Recurrence determinism, one of the fundamental characteristics of recurrence quantification analysis, measures predictability of a trajectory of a dynamical system. It is tightly connected with the conditional probability that, given a recurrence, following states of the trajectory will be recurrences. In this paper we study recurrence determinism of interval dynamical systems. We show that recurrence determinism distinguishes three main types of $\\omega$-limit sets of zero entropy maps: fini...

  20. An Analysis of Quality of Service (QoS In Live Video Streaming Using Evolved HSPA Network Media

    Directory of Open Access Journals (Sweden)

    Achmad Zakaria Azhar

    2016-10-01

    Full Text Available Evolved High Speed Packet Access (HSPA+ is a mobile telecommunication system technology and the evolution of HSPA technology. This technology has a packet data based service with downlink speeds up to 21.1 Mbps and uplink speed up to 11.5 Mbps on the bandwidth 5MHz. This technology is expected to fulfill and support the needs for information that involves all aspects of multimedia such as video and audio, especially live video streaming. By utilizing this technology it will facilitate communicating the information, for example to monitoring the situation of the house, the news coverage at some certain area, and other events in real time. This thesis aims to identify and test the Quality of Service (QoS performance on the network that is used for live video streaming with the parameters of throughput, delay, jitter and packet loss. The software used for monitoring the data traffic of the live video streaming network is wireshark network analyzer. From the test results it is obtained that the average throughput of provider B is 5,295 Kbps bigger than the provider A, the average delay of provider B is 0.618 ms smaller than the provider A, the average jitter of provider B is 0.420 ms smaller than the provider A and the average packet loss of provider B is 0.451% smaller than the provider A.

  1. Factors associated with recurrent bacterial empyema thoracis

    Directory of Open Access Journals (Sweden)

    Apichat Tantraworasin

    2018-07-01

    Full Text Available Summary: Background: Empyema thoracis (ET is one of the common thoracic diseases frequently found in developing countries. In the past, only a few studies have analyzed recurrent ET, and none had clearly identified the prognostic factors for recurrence. The aim of this study is to identify the prognostic factors of recurrent ET in Northern Thailand. Methods: A retrospective cohort study was conducted. All patients diagnosed with Stage II and III ET at Maharaj Nakorn Chiang Mai Hospital (a tertiary-care hospital in northern Thailand between January 1, 2007 and November 31, 2012 were enrolled in this study. All clinical data were extracted from the medical recording system. The primary outcome was recurrent disease. Multivariable Cox’s proportion hazard model was used to identify the independent prognostic factors for recurrence. Results: There were 382 patients enrolled in this study, and 34 patients (8.9% had recurrent disease. The most common gram-positive and gram-negative pathogens found were Staphylococcus aureus and Acinetobacter baumannii, respectively. Three independent prognostic factors for recurrent disease were nonsepsis status prior to the surgery [hazard ratio (HR = 12.3; 95% confidence interval (CI, 4.25–35.43], nonperforming decortication (HR = 5.4; 95% CI, 1.82–15.92, and persistent pleural spaces (HR = 4.1; 95% CI, 1.93–8.68. Conclusions: Clinical characteristics, surgical procedure, and persistent pleural spaces were independent prognostic factors for ET recurrence in this study. Decortication and early thoracoplasty in patients who had persistent pleural space should be considered. Large cohort studies are warranted to support these findings. Keywords: empyema thoracis, incidence, prognostic factor, pyothorax, recurrence

  2. Predictors for Recurrence of Chronic Subdural Hematoma.

    Science.gov (United States)

    Hammer, Alexander; Tregubow, Alexander; Kerry, Ghassan; Schrey, Michael; Hammer, Christian; Steiner, Hans-Herbert

    2017-01-01

    This prospective study was designed to analyze the dependence of different factors on the recurrence rate of chronic subdural hematoma (cSDH) after surgical treatment. Seventy-three consecutive patients, who were surgically treated at our department due to cSDH between 2009 and 2012, were included. The following parameters were analyzed: patient age and gender, occurrence of trauma, time between trauma and admission, neurological symptoms, presence of minor diseases, intake of anticoagulation medication. We classified the results of diagnostic imaging and determined the space-consuming effect via the cerebral midline shift. In addition, we scrutinized intraoperative findings and the dependence of the position of subdural drainage on the recurrence rate of cSDH. In our patient group, cSDH recurrence was significantly associated with aphasia (p=0.008). Moreover an increased cSDH recurrence rate was observed in the patient group that had a separated manifestation of the cSDH in the preoperative diagnostic imaging (p=0.048) and received no drainage implant (p=0.016). Homogeneous isodense cSDH was associated with no apparent recurrence (p=0.037). Within the scope of this study, we detected aphasia and separated cSDH as predictors of cSDH recurrence. Homogeneous isodense cSDH seems to be a good prognostic sign regarding the risk of recurrence development. Furthermore, our data clearly emphasize the importance of surgically applied drainage implants to prevent a recurrence of cSDH.

  3. Generalised recurrence plot analysis for spatial data

    International Nuclear Information System (INIS)

    Marwan, Norbert; Kurths, Juergen; Saparin, Peter

    2007-01-01

    Recurrence plot based methods are highly efficient and widely accepted tools for the investigation of time series or one-dimensional data. We present an extension of the recurrence plots and their quantifications in order to study recurrent structures in higher-dimensional spatial data. The capability of this extension is illustrated on prototypical 2D models. Next, the tested and proved approach is applied to assess the bone structure from CT images of human proximal tibia. We find that the spatial structures in trabecular bone become more recurrent during the bone loss in osteoporosis

  4. CT findings in recurrent pyogenic cholangitis

    International Nuclear Information System (INIS)

    Jung, Seung Hye; Lim, Jae Hoon; Ko, Young Tae; Lee, Dong Ho

    1991-01-01

    Recurrent pyogenic cholangitis is characterized clinically by recurrent attacks of right upper abdominal pain, fever and jaundice, and pathologically by chronic inflammation of the bile ducts with or without pigment bile duct stones. We analyzed the CT findings of 33 cases with recurrent pyogenic cholangitis. Twenty-four cases were confirmed by operation, and 9 cases were diagnosed clinically and cholangiographically. The CT findings of recurrent pyogenic cholangitis were dilatation of the intrahepatic ducts (n = 30), dilatation of the extrahepatic ducts (n = 24) intrahepatic stones (n = 16), extrahepatic stones (n = 12), stricture of the bile ducts (n = 10), wall enhancement of the bile ducts (n = 8), gallstones (n = 8), segmental atrophy of the liver (n = 7), pneumobilia (n = 4), abscess (n = 3), and segmental enhancement (n = 1) of the liver. A CT is considered helpful when sectional imaging is needed, but sonographic findings are equivocal or not confirmative; space-occupying lesions complicated with recurrent pyogenic cholangitis: hepatic resection is planned; and imaging guidance is needed for complex drainage procedures

  5. Meningeal infiltration in recurrent nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Chong, V.F.H.; Fan, Y.-F.

    2000-01-01

    Permeative infiltration of the meninges appears to be a distinct form of recurrent nasopharyngeal carcinoma (NPC). The present report of eight patients with recurrent NPC illustrates meningeal infiltration following basal foramina extension. Seven of the eight patients (88%) showed jugular foramen involvement. Three patients had concomitant infiltration of the foramen magnum. There was one patient showing spread through the foramen lacerum. Only four (50%) of these patients had clinically detectable tumour in the nasopharynx, while the other half showed deep submucosal recurrence with endoscopically unremarkable findings. Permeative meningeal infiltration appears to be a distinct form of NPC recurrence. It is important to recognize this phenomenon so as to optimize the treatment options. The imaging studies were reviewed and the following features were recorded: local nasopharyngeal recurrence, the manner of intracranial spread and site of meningeal infiltration. Four patients had only MRI, two had only CT and two patients had both CT and MRI. The presence or absence of intracranial tumour before treatment was also recorded. Two observers reviewed the images and results were arrived at by consensus. Copyright (1999) Blackwell Science Pty Ltd

  6. Local recurrence of metastatic brain tumor after surgery

    International Nuclear Information System (INIS)

    Shinoura, Nobusada; Yamada, Ryoji; Okamoto, Koichiro; Nakamura, Osamu; Shitara, Nobuyuki; Karasawa, Katsuyuki

    2006-01-01

    We analyzed factors associated with the local recurrence of brain metastases after surgery. Forty-seven patients with 67 metastatic brain tumors underwent surgery between 1994 and 2001. The survival time in the ''no recurrence'' group (34.7 months) was significantly longer than that in the recurrence group (21.9 months) (p=0.0008; log rank test). The factors affecting the local recurrence of brain metastases after surgery were as follows: cyst (p=0.0156), dural invasion (p=0.0029) of tumors, failure to totally remove tumors (p=0.0040), and lack of post-surgical irradiation (p<0.0001). Sex, age, tumor histology, tumor size, pre-surgical radiation, dose (≥45 vs <45, ≥50 vs <50 Gy) and the method (local vs whole brain) of post-surgical radiation did not affect the local recurrence rate of brain metastases after surgery. To avoid early recurrences of metastatic brain tumors, the factors associated with local recurrence should be considered in providing optimal treatment of tumors by surgery. (author)

  7. Salvage photodynamic therapy for recurrent nasopharyngeal carcinoma.

    Science.gov (United States)

    Succo, Giovanni; Rosso, S; Fadda, G L; Fantini, M; Crosetti, Erika

    2014-06-01

    To evaluate the feasibility of photodynamic therapy (NP-PDT) in the palliative management of recurrent/persistent nasopharyngeal cancer (NFC). Six patients with persistent/recurrent NPC underwent PDT with palliative intent. NP-PDT was delivered by three different methods depending on the localization, size and depth of the lesion: type I NP-PDT: transnasal direct illumination of postero-superior recurrence; type II NP-PDT: transnasal direct illumination of the whole nasopharynx; type III NP-PDT: transoral direct or interstitial illumination of lateral recurrence. In this case, the ENT-magnetic navigation system (MNS) was extremely useful in identifying the tumor and its distance from the ICA. Both patients treated with NP-PDT type I are free from disease at 38 and 71 months after treatment; both patients treated with NP-PDT type II experienced further local and loco-regional recurrence of disease within 16 months; one died of the disease while the second underwent a second palliative treatment, NP-PDT type I, and is currently living with the disease; of the two patients who underwent NP-PDT type III, one died as a result of regional and systemic recurrence without local recurrence while the second experienced a superficial recurrence. He underwent a second NP-PDT type III treatment and is currently free from disease at 21 months. NP-PDT is a non-invasive and simple treatment modality that may have an important role in the treatment of selected cases of persistent/recurrent NPC in its early stage, not suitable for a conventional therapeutic protocol. Coupling NP-PDT with the ENT-MNS can be an effective strategy to obtain more precise light delivery within the tumor, particularly in lateral and parapharyngeal localization. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  8. Prolapse Recurrence after Transvaginal Mesh Removal.

    Science.gov (United States)

    Rawlings, Tanner; Lavelle, Rebecca S; Coskun, Burhan; Alhalabi, Feras; Zimmern, Philippe E

    2015-11-01

    We determined the rate of pelvic organ prolapse recurrence after transvaginal mesh removal. Following institutional review board approval a longitudinally collected database of women undergoing transvaginal mesh removal for complications after transvaginal mesh placement with at least 1 year minimum followup was queried for pelvic organ prolapse recurrence. Recurrent prolapse was defined as greater than stage 1 on examination or the need for reoperation at the site of transvaginal mesh removal. Outcome measures were based on POP-Q (Pelvic Organ Prolapse Quantification System) at the last visit. Patients were grouped into 3 groups, including group 1--recurrent prolapse in the same compartment as transvaginal mesh removal, 2--persistent prolapse and 3--prolapse in a compartment different than transvaginal mesh removal. Of 73 women 52 met study inclusion criteria from 2007 to 2013, including 73% who presented with multiple indications for transvaginal mesh removal. The mean interval between insertion and removal was 45 months (range 10 to 165). Overall mean followup after transvaginal mesh removal was 30 months (range 12 to 84). In group 1 (recurrent prolapse) the rate was 15% (6 of 40 patients). Four women underwent surgery for recurrent prolapse at a mean 7 of months (range 5 to 10). Two patients elected observation. The rate of persistent prolapse (group 2) was 23% (12 of 52 patients). Three women underwent prolapse reoperation at a mean of 10 months (range 8 to 12). In group 3 (de novo/different compartment prolapse) the rate was 6% (3 of 52 patients). One woman underwent surgical repair at 52 months. At a mean 2.5-year followup 62% of patients (32 of 52) did not have recurrent or persistent prolapse after transvaginal mesh removal and 85% (44 of 52) did not undergo any further procedure for prolapse. Specifically for pelvic organ prolapse in the same compartment as transvaginal mesh removal 12% of patients had recurrence, of whom 8% underwent prolapse repair

  9. Identifying patients at high risk of tuberculosis recurrence

    Directory of Open Access Journals (Sweden)

    Ruxana T Sadikot

    2016-01-01

    Full Text Available Several studies have been done in relation to recurrence of tuberculosis (TB following completion of treatment. However, recurrence of TB is still a major problem from a public health perspective in high-burden countries, where no special attention is being given to this issue. Disease recurrence is an important indicator of the efficacy of antituberculosis treatment. The rate of recurrence is highly variable and has been estimated to range from 4.9% to 25%. This variability is not only a reflection of regional epidemiology of recurrence but differences in the definitions used by the TB control programs. In addition to treatment failure related to medication adherence, there are several key host factors that are associated with high rates of recurrence. The widely recognized host factors independent of treatment program that predispose to TB recurrence include: malnutrition; human immunodeficiency virus; substance abuse including tobacco use; comorbidity such as diabetes, renal failure and systemic diseases, especially immunosuppressive states; and environmental exposure such as silicosis. With improved understanding of the human genome, proteome, and metabolome, additional host-specific factors that predispose to recurrence are being discovered. Information on temporal and geographical trends of TB cases as well as genotyping might provide further information to enable us to fully understand TB recurrence and discriminate between reactivation and new infection. The recently launched World Health Organization End TB Strategy emphasizes the importance of integrated, patient-centered TB care. Continued improvement in diagnosis, treatment approaches, and defining host-specific factors are needed to fully understand the clinical epidemiological and social determinants of TB recurrence.

  10. Identifying patients at high risk of tuberculosis recurrence.

    Science.gov (United States)

    Sadikot, Ruxana T

    2016-12-01

    Several studies have been done in relation to recurrence of tuberculosis (TB) following completion of treatment. However, recurrence of TB is still a major problem from a public health perspective in high-burden countries, where no special attention is being given to this issue. Disease recurrence is an important indicator of the efficacy of antituberculosis treatment. The rate of recurrence is highly variable and has been estimated to range from 4.9% to 25%. This variability is not only a reflection of regional epidemiology of recurrence but differences in the definitions used by the TB control programs. In addition to treatment failure related to medication adherence, there are several key host factors that are associated with high rates of recurrence. The widely recognized host factors independent of treatment program that predispose to TB recurrence include: malnutrition; human immunodeficiency virus; substance abuse including tobacco use; comorbidity such as diabetes, renal failure and systemic diseases, especially immunosuppressive states; and environmental exposure such as silicosis. With improved understanding of the human genome, proteome, and metabolome, additional host-specific factors that predispose to recurrence are being discovered. Information on temporal and geographical trends of TB cases as well as genotyping might provide further information to enable us to fully understand TB recurrence and discriminate between reactivation and new infection. The recently launched World Health Organization End TB Strategy emphasizes the importance of integrated, patient-centered TB care. Continued improvement in diagnosis, treatment approaches, and defining host-specific factors are needed to fully understand the clinical epidemiological and social determinants of TB recurrence. Copyright © 2016.

  11. Radiotherapy for Locoregional Recurrent Cervix Cancer after Surgery

    International Nuclear Information System (INIS)

    Yang, Mi Gyoung

    1994-01-01

    Purpose: The role of radiotherapy in the management of patients with locoregional recurrent cervix cancer after radical surgery were retrospectively analyzed. Methods and materials: Twenty-eight patients treated with radiotherapy for locoregional recurrence after primary surgery for carcinoma of the cervix between 1989 and 1993 were analyzed. The median follow-up of survivors was 15 months (ranged 7-43 months). Eight patients had their disease confined to the vagina and 19 patients(68%) had pelvic mass as part of their locoregional recurrent disease. Within 24 months after the initial surgery, 82% of recurrences manifested themselves. All patients had whole pelvic irradiation with or without intracavitary radiotherapy(ICR). Results: Complete response(CR) was achieved in 18 patients(64%). Five of eighteen patients(28%) with initial CR developed second locoregional recurrence. Response to radiotherapy correlated strongly with tumor volume, site of recurrence and total radiation dose. The overall 2 year survival rate was 43% and the disease free survival was 31%. Survival rate was significantly influenced by the factors of interval from operation to recurrence, size and site of recurrent tumor, radiation dose, response of radiotherapy, lymph node status as initial presentation. The principal cause of death was lung metastasis(36%). Conclusion: Radiotherapy is an excellent modality for control of locoregional recurrent cervix cancer. To improve local control and survival rate, whole pelvic external radiotherapy in addition to ICR with more than 75.0Gy at the depth of 1.0cm from vaginal mucosa is needed and frequent follow up and early detection of recurrence is suggested as well

  12. On Rhythms in Neuronal Networks with Recurrent Excitation.

    Science.gov (United States)

    Börgers, Christoph; Takeuchi, R Melody; Rosebrock, Daniel T

    2018-02-01

    We investigate rhythms in networks of neurons with recurrent excitation, that is, with excitatory cells exciting each other. Recurrent excitation can sustain activity even when the cells in the network are driven below threshold, too weak to fire on their own. This sort of "reverberating" activity is often thought to be the basis of working memory. Recurrent excitation can also lead to "runaway" transitions, sudden transitions to high-frequency firing; this may be related to epileptic seizures. Not all fundamental questions about these phenomena have been answered with clarity in the literature. We focus on three questions here: (1) How much recurrent excitation is needed to sustain reverberating activity? How does the answer depend on parameters? (2) Is there a positive minimum frequency of reverberating activity, a positive "onset frequency"? How does it depend on parameters? (3) When do runaway transitions occur? For reduced models, we give mathematical answers to these questions. We also examine computationally to which extent our findings are reflected in the behavior of biophysically more realistic model networks. Our main results can be summarized as follows. (1) Reverberating activity can be fueled by extremely weak slow recurrent excitation, but only by sufficiently strong fast recurrent excitation. (2) The onset of reverberating activity, as recurrent excitation is strengthened or external drive is raised, occurs at a positive frequency. It is faster when the external drive is weaker (and the recurrent excitation stronger). It is slower when the recurrent excitation has a longer decay time constant. (3) Runaway transitions occur only with fast, not with slow, recurrent excitation. We also demonstrate that the relation between reverberating activity fueled by recurrent excitation and runaway transitions can be visualized in an instructive way by a (generalized) cusp catastrophe surface.

  13. Poincaré recurrences of DNA sequences

    Science.gov (United States)

    Frahm, K. M.; Shepelyansky, D. L.

    2012-01-01

    We analyze the statistical properties of Poincaré recurrences of Homo sapiens, mammalian, and other DNA sequences taken from the Ensembl Genome data base with up to 15 billion base pairs. We show that the probability of Poincaré recurrences decays in an algebraic way with the Poincaré exponent β≈4 even if the oscillatory dependence is well pronounced. The correlations between recurrences decay with an exponent ν≈0.6 that leads to an anomalous superdiffusive walk. However, for Homo sapiens sequences, with the largest available statistics, the diffusion coefficient converges to a finite value on distances larger than one million base pairs. We argue that the approach based on Poncaré recurrences determines new proximity features between different species and sheds a new light on their evolution history.

  14. Arthroscopic Bankart repair and capsular shift for recurrent anterior shoulder instability: functional outcomes and identification of risk factors for recurrence.

    Science.gov (United States)

    Ahmed, Issaq; Ashton, Fiona; Robinson, Christopher Michael

    2012-07-18

    Arthroscopic Bankart repair and capsular shift is a well-established technique for the treatment of anterior shoulder instability. The purpose of this study was to evaluate the outcomes following arthroscopic Bankart repair and capsular shift and to identify risk factors that are predictive of recurrence of glenohumeral instability. We performed a retrospective review of a prospectively collected database consisting of 302 patients who had undergone arthroscopic Bankart repair and capsular shift for the treatment of recurrent anterior glenohumeral instability. The prevalence of patient and injury-related risk factors for recurrence was assessed. Cox proportional hazards models were used to estimate the predicted probability of recurrence within two years. The chief outcome measures were the risk of recurrence and the two-year functional outcomes assessed with the Western Ontario shoulder instability index (WOSI) and disabilities of the arm, shoulder and hand (DASH) scores. The rate of recurrent glenohumeral instability after arthroscopic Bankart repair and capsular shift was 13.2%. The median time to recurrence was twelve months, and this complication developed within one year in 55% of these patients. The risk of recurrence was independently predicted by the patient's age at surgery, the severity of glenoid bone loss, and the presence of an engaging Hill-Sachs lesion (all p surgery. Varying the cutoff level for the predicted probability of recurrence in the model from 50% to lower values increased the sensitivity of the model to detect recurrences but decreased the positive predictive value of the model to correctly predict failed repairs. There was a significant improvement in the mean WOSI and DASH scores at two years postoperatively (both p instability and individualizing treatment options for particular groups of patients. Prognostic level I. See Instructions for authors for a complete description of levels of evidence.

  15. Stakeholders' views of recurrent sore throat, tonsillitis and their management: a qualitative interview study for the NAtional Trial of Tonsillectomy IN Adults (NATTINA Part 1).

    Science.gov (United States)

    McSweeney, L A; Rousseau, N S; Wilson, J A; Wilkes, S; Haighton, C A

    2017-04-01

    To determine the impact of recurrent sore throats and tonsillitis in adults and stakeholder views of treatment pathways. Qualitative semistructured interview design reporting novel data from a feasibility study for a UK national trial of tonsillectomy in adults. Nine study sites linked to ear, nose and throat departments in National Health Service hospitals located across the United Kingdom. Fifteen patients, 11 general practitioners and 22 ear, nose and throat staff consented to in-depth interviews, which were analysed using a framework analysis approach. Views of stakeholder groups. Recurrent sore throats were reported to severely impact patients' family, work and social life. Ear, nose and throat staff stated that patients faced increasing barriers to secondary care service access. General practitioners were under pressure to reduce 'limited clinical value' surgical procedures. The findings from this study suggest that there is a disconnect between the attitudes of the stakeholders and the reality of recurrent sore throat, tonsillectomy procedures and service provision. More evidence for the role of tonsillectomy is needed from randomised controlled trials to determine whether it should continue to be ranked as a procedure of limited clinical effectiveness. © 2016 John Wiley & Sons Ltd.

  16. 10 CFR 625.3 - Standard sales provisions.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Standard sales provisions. 625.3 Section 625.3 Energy DEPARTMENT OF ENERGY (CONTINUED) SALES REGULATION PRICE COMPETITIVE SALE OF STRATEGIC PETROLEUM RESERVE PETROLEUM § 625.3 Standard sales provisions. (a) Contents. The Standards Sales Provisions shall contain...

  17. 6th International Symposium on Recurrence Plots

    CERN Document Server

    Jr, Jr; Ioana, Cornel; Marwan, Norbert

    2016-01-01

    The chapters in this book originate from the research work and contributions presented at the Sixth International Symposium on Recurrence Plots held in Grenoble, France in June 2015. Scientists from numerous disciplines gathered to exchange knowledge on recent applications and developments in recurrence plots and recurrence quantification analysis. This meeting was remarkable because of the obvious expansion of recurrence strategies (theory) and applications (practice) into ever-broadening fields of science. It discusses real-world systems from various fields, including mathematics, strange attractors, applied physics, physiology, medicine, environmental and earth sciences, as well as psychology and linguistics. Even readers not actively researching any of these particular systems will benefit from discovering how other scientists are finding practical non-linear solutions to specific problems. The book is of interest to an interdisciplinary audience of recurrence plot users and researchers interested in time...

  18. Re-recurrence after operation for recurrent inguinal hernia. A nationwide 8-year follow-up study on the role of type of repair

    DEFF Research Database (Denmark)

    Bisgaard, Thue; Bay-Nielsen, M.; Kehlet, H.

    2008-01-01

    the surgical strategy and results after recurrent inguinal hernia repairs. METHODS: Prospective recording of all primary and subsequent recurrent inguinal hernia repairs from January 1, 1998 to December 31, 2005, in the national Danish Hernia Database, using the reoperation rate as a proxy for recurrence...... = 1124) was significantly reduced after laparoscopic operation for recurrence (1.3% (95% CI: 0.4-3.0)) compared with open repairs for recurrence (Lichtenstein 11.3% (8.2-15.2), nonmesh 19.2% (14.0-25.4), mesh (non-Lichtenstein) 7.2% (4.0 - 11.8)). After primary nonmesh (n = 616), non-Lichtenstein mesh (n...... = 277), and laparoscopic repair (n = 100) there was no significant difference in re-reoperation rates between a laparoscopic repair and all open techniques of repair for recurrence. CONCLUSION: Laparoscopic repair is recommended for reoperation of a recurrence after primary open Lichtenstein repair...

  19. Analisis Quality of Service (QoS Jaringan Telekomunikasi High-Speed Downlink Packet Access (HSDPA pada Teknologi 3.5G

    Directory of Open Access Journals (Sweden)

    Mey Fenny Wati Simanjuntak

    2016-01-01

    Full Text Available Sejak layanan teknologi 3G pertama kali diperkenalkan, permintaan akan layanan berbasis paket data dari tahun ke tahun mengalami peningkatan yang pesat. Menanggapi hal tersebut, para penyedian jaringan telekomunikasi terus berusaha untuk meningkatkan kemampuan jaringannya. Salah satu solusinya menerapkan teknologi High-Speed Downlink Packet Access yang direkomendasikan oleh 3GPP Release 5. Penelitian ini dikhususkan untuk menganalisis Quality of Service jaringan telekomunikasi High-Speed Downlink Packet Access di Kecamatan Tembalang Kota Semarang. Analisis Quality of Service jaringan telekomunikasi High-Speed Downlink Packet Access pada penelitian ini bertujuan untuk memberikan gambaran kualitas jaringan telekomunikasi High-Speed Downlink Packet Access dari sisi bandwidth, throughput, packet loss dan delay. Metode penelitian yang dibahas dalam penelitian ini yaitu penelitian kualitatif observatif, dimana akan dilakukan pengamatan tentang bagaimana QoS jaringan telekomunikasi High-Speed Downlink Packet Access pada teknologi 3.5G di Kecamatan Tembalang Kota Semarang. Proses pengamatan dalam menganalisis Quality of Service jaringan telekomunikasi High-Speed Downlink Packet Access di Kecamatan Tembalang Kota Semarang berdasarkan 4 parameter diantaranya bandwidth, throughput, packet loss dan delay. Aplikasi yang digunakan yaitu monitoring application Elnus Bandwidth Meter dan Axence NetTools Professional 4.0. Selain itu, Quality of Service jaringan telekomunikasi High- Speed Downlink Packet Access di Kecamatan Tembalang Kota Semarang diamati berdasarkan waktu yaitu harian, mingguan dan bulanan.

  20. Recurrence risk of ictal asystole in epilepsy.

    Science.gov (United States)

    Hampel, Kevin G; Thijs, Roland D; Elger, Christian E; Surges, Rainer

    2017-08-22

    To determine the recurrence risk of ictal asystole (IA) and its determining factors in people with epilepsy. We performed a systematic review of published cases with IA in 3 databases and additionally searched our local database for patients with multiple seizures simultaneously recorded with ECG and EEG and at least one IA. IA recurrence risk was estimated by including all seizures without knowledge of the chronological order. Various clinical features were assessed by an individual patient data meta-analysis. A random mixed effect logistic regression model was applied to estimate the average recurrence risk of IA. Plausibility of the calculated IA recurrence risk was checked by analyzing the local dataset with available information in chronological order. Eighty patients with 182 IA in 537 seizures were included. Recurrence risk of IA amounted to 40% (95% confidence interval [CI] 32%-50%). None of the clinical factors (age, sex, type and duration of epilepsy, hemispheric lateralization, duration of IA per patient) appeared to have a significant effect on the short-term recurrence risk of IA. When considering the local dataset only, IA recurrence risk was estimated to 30% (95% CI 14%-53%). Information whether IA coincided with symptoms (i.e., syncope) or not was given in 60 patients: 100 out of 142 IAs were symptomatic. Our data suggest that in case of clinically suspected IA, the recording of 1 or 2 seizures is not sufficient to rule out IA. Furthermore, the high short-term recurrence risk favors aggressive treatment, including pacemaker implantation if seizure freedom cannot be achieved. Copyright © 2017 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology.

  1. Recurrence of hypertensive disorders of pregnancy

    DEFF Research Database (Denmark)

    van Oostwaard, Miriam F; Langenveld, Josje; Schuit, Ewoud

    2015-01-01

    OBJECTIVE: We performed an individual participant data (IPD) metaanalysis to calculate the recurrence risk of hypertensive disorders of pregnancy (HDP) and recurrence of individual hypertensive syndromes. STUDY DESIGN: We performed an electronic literature search for cohort studies that reported ...

  2. Modeling the recurrent failure to thrive in less than two-year children: recurrent events survival analysis.

    Science.gov (United States)

    Saki Malehi, Amal; Hajizadeh, Ebrahim; Ahmadi, Kambiz; Kholdi, Nahid

    2014-01-01

    This study aimes to evaluate the failure to thrive (FTT) recurrent event over time. This longitudinal study was conducted during February 2007 to July 2009. The primary outcome was growth failure. The analysis was done using 1283 children who had experienced FTT several times, based on recurrent events analysis. Fifty-nine percent of the children had experienced the FTT at least one time and 5.3% of them had experienced it up to four times. The Prentice-Williams-Peterson (PWP) model revealed significant relationship between diarrhea (HR=1.26), respiratory infections (HR=1.25), urinary tract infections (HR=1.51), discontinuation of breast-feeding (HR=1.96), teething (HR=1.18), initiation age of complementary feeding (HR=1.11) and hazard rate of the first FTT event. Recurrence nature of the FTT is a main problem, which taking it into account increases the accuracy in analysis of FTT event process and can lead to identify different risk factors for each FTT recurrences.

  3. Recurrent odontogenic keratocyst within the masticatory space

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Su Yeon; Huh, Kyung Hoe; Yi, Won Jin; Choi, Hyun Bae; Choi, Soon Chul [School of Dentistry, Seoul National University, Seoul (Korea, Republic of)

    2008-06-15

    The odontogenic keratocyst (OKC) is a developmental odontogenic cyst typically occurring in the jaws. Since the first description of OKC was published in 1956, the lesion has been of particular interest because of its specific histopathologic features, high recurrence rate, and aggressive behavior. Recurrences most commonly arise within bone at the site of the original cyst. However, as lining cells may find their way into surrounding tissues either from implantation during surgery or from cortical perforation recurrences may arise at a distance from the original cyst. Here, we report a rare case of recurrent OKC which was first developed in mandible and recurred within the masticatory space.

  4. Recurrent odontogenic keratocyst within the masticatory space

    International Nuclear Information System (INIS)

    Lim, Su Yeon; Huh, Kyung Hoe; Yi, Won Jin; Choi, Hyun Bae; Choi, Soon Chul

    2008-01-01

    The odontogenic keratocyst (OKC) is a developmental odontogenic cyst typically occurring in the jaws. Since the first description of OKC was published in 1956, the lesion has been of particular interest because of its specific histopathologic features, high recurrence rate, and aggressive behavior. Recurrences most commonly arise within bone at the site of the original cyst. However, as lining cells may find their way into surrounding tissues either from implantation during surgery or from cortical perforation recurrences may arise at a distance from the original cyst. Here, we report a rare case of recurrent OKC which was first developed in mandible and recurred within the masticatory space.

  5. Provisions distributed

    NARCIS (Netherlands)

    Martin Olsthoorn; Evert Pommer; Michiel Ras; Ab van der Torre; Jean Marie Wildeboer Schut

    2017-01-01

    Original title: Voorzieningen verdeeld Citizens ‘profit’ from the government when they receive income support because they are unable to generate an income themselves. They also profit when they make use of provisions such as care, support, education, public transport, sport, culture

  6. Validation of the 12-gene colon cancer recurrence score as a predictor of recurrence risk in stage II and III rectal cancer patients.

    Science.gov (United States)

    Reimers, Marlies S; Kuppen, Peter J K; Lee, Mark; Lopatin, Margarita; Tezcan, Haluk; Putter, Hein; Clark-Langone, Kim; Liefers, Gerrit Jan; Shak, Steve; van de Velde, Cornelis J H

    2014-11-01

    The 12-gene Recurrence Score assay is a validated predictor of recurrence risk in stage II and III colon cancer patients. We conducted a prospectively designed study to validate this assay for prediction of recurrence risk in stage II and III rectal cancer patients from the Dutch Total Mesorectal Excision (TME) trial. RNA was extracted from fixed paraffin-embedded primary rectal tumor tissue from stage II and III patients randomized to TME surgery alone, without (neo)adjuvant treatment. Recurrence Score was assessed by quantitative real time-polymerase chain reaction using previously validated colon cancer genes and algorithm. Data were analysed by Cox proportional hazards regression, adjusting for stage and resection margin status. All statistical tests were two-sided. Recurrence Score predicted risk of recurrence (hazard ratio [HR] = 1.57, 95% confidence interval [CI] = 1.11 to 2.21, P = .01), risk of distant recurrence (HR = 1.50, 95% CI = 1.04 to 2.17, P = .03), and rectal cancer-specific survival (HR = 1.64, 95% CI = 1.15 to 2.34, P = .007). The effect of Recurrence Score was most prominent in stage II patients and attenuated with more advanced stage (P(interaction) ≤ .007 for each endpoint). In stage II, five-year cumulative incidence of recurrence ranged from 11.1% in the predefined low Recurrence Score group (48.5% of patients) to 43.3% in the high Recurrence Score group (23.1% of patients). The 12-gene Recurrence Score is a predictor of recurrence risk and cancer-specific survival in rectal cancer patients treated with surgery alone, suggesting a similar underlying biology in colon and rectal cancers. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  7. Recurrent Tricuspid Insufficiency

    Science.gov (United States)

    Kara, Ibrahim; Koksal, Cengiz; Cakalagaoglu, Canturk; Sahin, Muslum; Yanartas, Mehmet; Ay, Yasin; Demir, Serdar

    2013-01-01

    This study compares the medium-term results of De Vega, modified De Vega, and ring annuloplasty techniques for the correction of tricuspid insufficiency and investigates the risk factors for recurrent grades 3 and 4 tricuspid insufficiency after repair. In our clinic, 93 patients with functional tricuspid insufficiency underwent surgical tricuspid repair from May 2007 through October 2010. The study was retrospective, and all the data pertaining to the patients were retrieved from hospital records. Functional capacity, recurrent tricuspid insufficiency, and risk factors aggravating the insufficiency were analyzed for each patient. In the medium term (25.4 ± 10.3 mo), the rates of grades 3 and 4 tricuspid insufficiency in the De Vega, modified De Vega, and ring annuloplasty groups were 31%, 23.1%, and 6.1%, respectively. Logistic regression analysis revealed that chronic obstructive pulmonary disease, left ventricular dysfunction (ejection fraction, tricuspid insufficiency. Medium-term survival was 90.6% for the De Vega group, 96.3% for the modified De Vega group, and 97.1% for the ring annuloplasty group. Ring annuloplasty provided the best relief from recurrent tricuspid insufficiency when compared with DeVega annuloplasty. Modified De Vega annuloplasty might be a suitable alternative to ring annuloplasty when rings are not available. PMID:23466680

  8. Obligatory provisions for nuclear power plants

    International Nuclear Information System (INIS)

    Cloosters, W.

    2008-01-01

    To cover the expenses associated with decommissioning and disposal of their nuclear power plants, German nuclear power plant operators set aside a total of more than EUR 30 billion and entered the respective provisions into their balance sheets. One point of eminent importance in this regard is the question whether these provisions are adequate in amount and permitted under accounting and tax laws. The other point to be considered is whether the funds will be available reliably if and when needed. Against the backdrop of these issues, the practice and importance of making these provisions are described. This is followed by an outline of the basic accounting and taxation aspects. It is seen that obligations under public law can be the basis of financial provisions only if there is a obligation sufficiently concrete in terms of time and object. The following examination of applicable obligations under the Atomic Energy Act incumbent upon nuclear power plant operators with regard to decommissioning and disposal results in the finding that such obligations are only partly regulated in the Atomic Energy Act, and that specifications in terms of time and purpose are insufficient. If the national practice of making financial provisions is to be put on a reliable basis, it is recommended to express the law on decommissioning and its mode of financing in more concrete terms in the Atomic Energy Act. In addition to unequivocal decommissioning and disposal obligations, the Atomic Energy Act should also incorporate regulations about financial provisions for decomissioning which are in need of more precise language. The present practice of making provisions is characterized by the risk that the funds necessary for planned decommissioning and disposal may not be available when needed. It is against this background that possible solutions reducing that risk are discussed. A recommendation is expressed to establish a public fund for decommissioning and disposal to which the

  9. Second-order analysis of semiparametric recurrent event processes.

    Science.gov (United States)

    Guan, Yongtao

    2011-09-01

    A typical recurrent event dataset consists of an often large number of recurrent event processes, each of which contains multiple event times observed from an individual during a follow-up period. Such data have become increasingly available in medical and epidemiological studies. In this article, we introduce novel procedures to conduct second-order analysis for a flexible class of semiparametric recurrent event processes. Such an analysis can provide useful information regarding the dependence structure within each recurrent event process. Specifically, we will use the proposed procedures to test whether the individual recurrent event processes are all Poisson processes and to suggest sensible alternative models for them if they are not. We apply these procedures to a well-known recurrent event dataset on chronic granulomatous disease and an epidemiological dataset on meningococcal disease cases in Merseyside, United Kingdom to illustrate their practical value. © 2011, The International Biometric Society.

  10. Recurrence of Dupuytren's contracture: A consensus-based definition.

    Directory of Open Access Journals (Sweden)

    Hester J Kan

    Full Text Available One of the major determinants of Dupyutren disease (DD treatment efficacy is recurrence of the contracture. Unfortunately, lack of agreement in the literature on what constitutes recurrence makes it nearly impossible to compare the multiple treatments alternatives available today. The aim of this study is to bring an unbiased pool of experts to agree upon what would be considered a recurrence of DD after treatment; and from that consensus establish a much-needed definition for DD recurrence.To reach an expert consensus on the definition of recurrence we used the Delphi method and invited 43 Dupuytren's research and treatment experts from 10 countries to participate by answering a series of questionnaire rounds. After each round the answers were analyzed and the experts received a feedback report with another questionnaire round to further hone in of the definition. We defined consensus when at least 70% of the experts agreed on a topic.Twenty-one experts agreed to participate in this study. After four consensus rounds, we agreed that DD recurrence should be defined as "more than 20 degrees of contracture recurrence in any treated joint at one year post-treatment compared to six weeks post-treatment". In addition, "recurrence should be reported individually for every treated joint" and afterwards measurements should be repeated and reported yearly.This study provides the most comprehensive to date definition of what should be considered recurrence of DD. These standardized criteria should allow us to better evaluate the many treatment alternatives.

  11. CT diagnosis of recurrence following resection for gastric carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Cho, On Koo; Cho, Hye Young; Kim, Soon Yong [Hanyag University College of Medicine, Seoul (Korea, Republic of)

    1988-10-15

    There is almost complete lack of specific reference to the findings of recurrent gastric carcinoma except a few data which have been based on autopsy findings. The purpose of this study is to demonstrate the usefulness of CT for defining the pattern of recurrence and to compare the results of convectional barium studies to identify the lesion. 1. There were 64 cases of postgastrectomy CT scan of gastric carcinoma during recent 3 years and recurrence evidence was identified in 53 cases. 2. Time lapse between operation and detection of recurrence was variable from 3 months to 6 years. Evidence of recurrence less than 1 year were stage III and IV patients and long survivors more than 5 years were stage I and III patients. 3. Local recurrence of gastric remnant or anastomosis area was identified in 10 cases. Regional recurrence was noted in 28 cases including 13 gastric bed and 26 lymph node enlargement. Most frequently enlarged nodes were peripancreatic and paraaortic nodes. 4. Peritoneal spread was the most frequent pattern of recurrence occurring in 34 cases. Mesenteric mass and ascites were most frequent findings. 5. Distant metastasis was noted in 12 cases and the liver was the most frequent site. 6. Local recurrence was detected in barium study in half of the cases. Peritoneal seeding was relatively well identified but regional recurrence was very poorly identified.

  12. Economic Loan Loss Provision and Expected Loss

    Directory of Open Access Journals (Sweden)

    Stefan Hlawatsch

    2010-10-01

    Full Text Available The intention of a loan loss provision is the anticipation of the loan's expected losses by adjusting the book value of the loan. Furthermore, this loan loss provision has to be compared to the expected loss according to Basel II and, in the case of a difference, liable equity has to be adjusted. This however assumes that the loan loss provision and the expected loss are based on a similar economic rationale, which is only valid conditionally in current loan loss provisioning methods according to IFRS. Therefore, differences between loan loss provisions and expected losses should only result from different approaches regarding the parameter estimation within each model and not due to different assumptions regarding the outcome of the model. The provisioning and accounting model developed in this paper overcomes the before-mentioned shortcomings and is consistent with an economic rationale of expected losses. Additionally, this model is based on a close-to-market valuation of the loan that is in favor of the basic idea of IFRS. Suggestions for changes in current accounting and capital requirement rules are provided.

  13. Studies on recurrence of colorectal carcinoma

    International Nuclear Information System (INIS)

    Kobayashi, Masayuki; Nosaki, Tadaharu; Murai, Tomoya; Ooshita, Ikuo; Kobayashi, Suzuo

    1989-01-01

    Recurrence patterns of colorectal carcinoma were studied in 402 patients followed up for 5 years or more after surgery. Recurrence was observed in 23% for colon cancer and 38% for rectal canccer. The most frequent site of recurrence or relapse in cases of colon cancer was the liver, followed by multiple organs and a local region; and in the case of rectal cancer, it was multiple organs, followed by a local region, the liver, lung, and bone. The rate of recurrence or relapse tended to be higher in patients with lymph node metastases or more advanced clinical stage. Liver relapse was seen in 13% for colon cancer and 12% for rectal cancer, occurring within 48 months after surgery. Since CT can detect liver relapse within 24 months, abdominal CT and chest plain roentgenography should be performed in the first 6 months, 12 months, and 24 months after surgery. (Namekawa, K)

  14. Dynamic SLA Negotiation in Autonomic Federated Environments

    Science.gov (United States)

    Rubach, Pawel; Sobolewski, Michael

    Federated computing environments offer requestors the ability to dynamically invoke services offered by collaborating providers in the virtual service network. Without an efficient resource management that includes Dynamic SLA Negotiation, however, the assignment of providers to customer's requests cannot be optimized and cannot offer high reliability without relevant SLA guarantees. We propose a new SLA-based SERViceable Metacomputing Environment (SERVME) capable of matching providers based on QoS requirements and performing autonomic provisioning and deprovisioning of services according to dynamic requestor needs. This paper presents the SLA negotiation process that includes on-demand provisioning and uses an object-oriented SLA model for large-scale service-oriented systems supported by SERVME. An initial reference implementation in the SORCER environment is also described.

  15. RECURRENT NOVAE IN M31

    Energy Technology Data Exchange (ETDEWEB)

    Shafter, A. W. [Department of Astronomy, San Diego State University, San Diego, CA 92182 (United States); Henze, M. [European Space Astronomy Centre, P.O. Box 78, E-28692 Villanueva de la Cañada, Madrid (Spain); Rector, T. A. [Department of Physics and Astronomy, University of Alaska Anchorage, 3211 Providence Dr., Anchorage, AK 99508 (United States); Schweizer, F. [Carnegie Observatories, 813 Santa Barbara St., Pasadena, CA 91101 (United States); Hornoch, K. [Astronomical Institute, Academy of Sciences, CZ-251 65 Ondřejov (Czech Republic); Orio, M. [Astronomical Observatory of Padova (INAF), I-35122 Padova (Italy); Pietsch, W. [Max Planck Institute for Extraterrestrial Physics, P.O. Box 1312, Giessenbachstr., D-85741, Garching (Germany); Darnley, M. J.; Williams, S. C.; Bode, M. F. [Astrophysics Research Institute, Liverpool John Moores University, Liverpool L3 5RF (United Kingdom); Bryan, J., E-mail: aws@nova.sdsu.edu [McDonald Observatory, Austin, TX 78712 (United States)

    2015-02-01

    The reported positions of 964 suspected nova eruptions in M31 recorded through the end of calendar year 2013 have been compared in order to identify recurrent nova (RN) candidates. To pass the initial screen and qualify as a RN candidate, two or more eruptions were required to be coincident within 0.′1, although this criterion was relaxed to 0.′15 for novae discovered on early photographic patrols. A total of 118 eruptions from 51 potential RN systems satisfied the screening criterion. To determine what fraction of these novae are indeed recurrent, the original plates and published images of the relevant eruptions have been carefully compared. This procedure has resulted in the elimination of 27 of the 51 progenitor candidates (61 eruptions) from further consideration as RNe, with another 8 systems (17 eruptions) deemed unlikely to be recurrent. Of the remaining 16 systems, 12 candidates (32 eruptions) were judged to be RNe, with an additional 4 systems (8 eruptions) being possibly recurrent. It is estimated that ∼4% of the nova eruptions seen in M31 over the past century are associated with RNe. A Monte Carlo analysis shows that the discovery efficiency for RNe may be as low as 10% that for novae in general, suggesting that as many as one in three nova eruptions observed in M31 arise from progenitor systems having recurrence times ≲100 yr. For plausible system parameters, it appears unlikely that RNe can provide a significant channel for the production of Type Ia supernovae.

  16. Transnasal endoscopic medial maxillectomy in recurrent maxillary sinus inverted papilloma.

    Science.gov (United States)

    Kamel, Reda H; Abdel Fattah, Ahmed F; Awad, Ayman G

    2014-12-01

    Maxillary sinus inverted papilloma entails medial maxillectomy and is associated with high incidence of recurrence. To study the impact of prior surgery on recurrence rate after transnasal endoscopic medial maxillectomy. Eighteen patients with primary and 33 with recurrent maxillary sinus inverted papilloma underwent transnasal endoscopic medial maxillectomy. Caldwell-Luc operation was the primary surgery in 12 patients, transnasal endoscopic resection in 20, and midfacial degloving technique in one. The follow-up period ranged between 2 to 19.5 years with an average of 8.8 years. Recurrence was detected in 8/51 maxillary sinus inverted papilloma patients (15.7 %), 1/18 of primary cases (5.5 %), 7/33 of recurrent cases (21.2 %); 3/20 of the transnasal endoscopic resection group (15%) and 4/12 of the Caldwell-Luc group (33.3%). Redo transnasal endoscopic medial maxillectomy was followed by a single recurrence in the Caldwell-Luc group (25%), and no recurrence in the other groups. Recurrence is more common in recurrent maxillary sinus inverted papilloma than primary lesions. Recurrent maxillary sinus inverted papilloma after Caldwell-Luc operation has higher incidence of recurrence than after transnasal endoscopic resection.

  17. Equivalence of Equilibrium Propagation and Recurrent Backpropagation

    OpenAIRE

    Scellier, Benjamin; Bengio, Yoshua

    2017-01-01

    Recurrent Backpropagation and Equilibrium Propagation are algorithms for fixed point recurrent neural networks which differ in their second phase. In the first phase, both algorithms converge to a fixed point which corresponds to the configuration where the prediction is made. In the second phase, Recurrent Backpropagation computes error derivatives whereas Equilibrium Propagation relaxes to another nearby fixed point. In this work we establish a close connection between these two algorithms....

  18. Surgical treatment for residual or recurrent strabismus

    Directory of Open Access Journals (Sweden)

    Tao Wang

    2014-12-01

    Full Text Available Although the surgical treatment is a relatively effective and predictable method for correcting residual or recurrent strabismus, such as posterior fixation sutures, medial rectus marginal myotomy, unilateral or bilateral rectus re-recession and resection, unilateral lateral rectus recession and adjustable suture, no standard protocol is established for the surgical style. Different surgical approaches have been recommended for correcting residual or recurrent strabismus. The choice of the surgical procedure depends on the former operation pattern and the surgical dosages applied on the patients, residual or recurrent angle of deviation and the operator''s preference and experience. This review attempts to outline recent publications and current opinion in the management of residual or recurrent esotropia and exotropia.

  19. Differential proteomic profiling of primary and recurrent chordomas.

    Science.gov (United States)

    Chen, Su; Xu, Wei; Jiao, Jian; Jiang, Dongjie; Liu, Jian; Chen, Tenghui; Wan, Zongmiao; Xu, Leqin; Zhou, Zhenhua; Xiao, Jianru

    2015-05-01

    Chordomas are locally destructive tumors with high rates of recurrence and a poor prognosis. The mechanisms involved in chordoma recurrence remain largely unknown. In the present study, we examined the proteomic profile of a chordoma primary tumor (CSO) and a recurrent tumor (CSR) through mass spectrum in a chordoma patient who underwent surgery. Bioinformatic analysis of the profile showed that 359 proteins had a significant expression difference and 21 pathways had a striking alteration between the CSO and the CSR. The CSR showed a significant increase in carbohydrate metabolism. Immunohistochemistry (IHC) confirmed that the cancer stem cell marker activated leukocyte cell adhesion molecule (ALCAM or CD166) expression level was higher in the recurrent than that in the primary tumor. The present study analyzed the proteomic profile change between CSO and CSR and identified a new biomarker ALCAM in recurrent chordomas. This finding sheds light on unraveling the pathophysiology of chordoma recurrence and on exploring more effective prognostic biomarkers and targeted therapies against this devastating disease.

  20. Recurrence quantity analysis based on matrix eigenvalues

    Science.gov (United States)

    Yang, Pengbo; Shang, Pengjian

    2018-06-01

    Recurrence plots is a powerful tool for visualization and analysis of dynamical systems. Recurrence quantification analysis (RQA), based on point density and diagonal and vertical line structures in the recurrence plots, is considered to be alternative measures to quantify the complexity of dynamical systems. In this paper, we present a new measure based on recurrence matrix to quantify the dynamical properties of a given system. Matrix eigenvalues can reflect the basic characteristics of the complex systems, so we show the properties of the system by exploring the eigenvalues of the recurrence matrix. Considering that Shannon entropy has been defined as a complexity measure, we propose the definition of entropy of matrix eigenvalues (EOME) as a new RQA measure. We confirm that EOME can be used as a metric to quantify the behavior changes of the system. As a given dynamical system changes from a non-chaotic to a chaotic regime, the EOME will increase as well. The bigger EOME values imply higher complexity and lower predictability. We also study the effect of some factors on EOME,including data length, recurrence threshold, the embedding dimension, and additional noise. Finally, we demonstrate an application in physiology. The advantage of this measure lies in a high sensitivity and simple computation.

  1. Association Between BMI and Recurrence of Primary Spontaneous Pneumothorax.

    Science.gov (United States)

    Tan, Juntao; Yang, Yang; Zhong, Jianhong; Zuo, Chuantian; Tang, Huamin; Zhao, Huimin; Zeng, Guang; Zhang, Jianfeng; Guo, Jianji; Yang, Nuo

    2017-05-01

    Whether body mass index (BMI) is a significant risk factor for recurrence of primary spontaneous pneumothorax (PSP) remains controversial. The purpose of this study was to examine whether BMI and other factors are linked to risk of PSP recurrence. A consecutive cohort of 273 patients was retrospectively evaluated. Patients were divided into those who experienced recurrence (n = 81) and those who did not (n = 192), as well as into those who had low BMI (n = 75) and those who had normal or elevated BMI (n = 198). The two pairs of groups were compared in terms of baseline data, and Cox proportional hazards modeling was used to identify predictors of PSP recurrence. Rates of recurrence among all 273 patients were 20.9% at 1 year, 23.8% at 2 years, and 28.7% at 5 years. Univariate analysis identified the following significant predictors of PSP recurrence: height, weight, BMI, size of pneumothorax, and treatment modality. Multivariate analyses identified several risk factors for PSP recurrence: low BMI, pneumothorax size ≥50%, and non-surgical treatment. Kaplan-Meier survival analysis indicated that patients with low BMI showed significantly lower recurrence-free survival than patients with normal or elevated BMI (P pneumothorax size ≥50%, and non-surgical treatment were risk factors for PSP recurrence in our cohort. Low BMI may be a clinically useful predictor of PSP recurrence.

  2. Models of Public Service Provision

    DEFF Research Database (Denmark)

    Andersen, Lotte Bøgh; Kristensen, Nicolai; Pedersen, Lene Holm

    2013-01-01

    This article extends the framework of Le Grand (2003, 2010) to encompass responsiveness, and the main argument is that the combination of employee motivation, user capacity, and models of public service provision potentially has serious implications for responsiveness across service areas. Although...... research on employee motivation thrives, especially in the public service motivation (PSM) literature, few studies have investigated user capacity empirically, and we know little about the combination of PSM, user capacity and models of service provision. Analyzing four central service areas (day care......, schools, hospitals, and universities), we find variations in both user capacity and PSM. Taking this variation as a point of departure we discuss what implications different combinations of employee motivation, user capacity, and models of public service provision may have for responsiveness....

  3. EARLY RECURRENCE OF WELL-DIFFERENTIATED ENDOMETRIAL CANCER (A CASE REPORT

    Directory of Open Access Journals (Sweden)

    N. E. Levchrnko

    2017-01-01

    Full Text Available Endometrial cancer is the 6-th most common malignancy in women worldwide, accounting for about 4.8 % of all female cancers. The treatment of recurrent endometrial cancer remains a major challenge. Some endometrial cancer recurrences, for example vaginal stump recurrence, are reported to be effectively treated with surgical resection and radiation therapy. Early recurrence of early-stage well-differentiated endometrial cancer is uncommon. Case report. Herein we report a rare case of recurrent well-differentiated endometrial cancer in a 65-year-old woman. The patient had recurrence 10 months after laparoscopic hysterectomy with bilateral salpingo-oophorectomy. Recurrent endometrial tumor with extension into the rectosigmoid colon, urinary bladder and the right ureter manifested itself clinically with severe pain requiring the use of opioids. The recurrent tumor was removed. Resection of the bladder, left ureter and upper ampular rectum was followed by anastomosis. The patient received multiple cycles of chemotherapy. Conclusion. Compliance with the principles of ablastics during the laparoscopic or laparotomic surgery helps to avoid recurrence in patients with prognostically favorable cancer. In case of recurrence, combined operations are the only possible chance of improving survival of patients with locally advanced or recurrent tumors, which are insensitive to chemoradiotherapy.

  4. Assessment of sleep quality in benign paroxysmal positional vertigo recurrence.

    Science.gov (United States)

    Wang, Yun; Fei Xia, Fei; Wang, Wei; Hu, Wenli

    2018-06-08

    Despite the availability of highly effective treatments, there is a significant recurrence rate of benign paroxysmal positional vertigo (BPPV). This study is aimed to quantitatively measure sleep quality in BPPV patients and correlate it with the recurrence of BPPV. In this longitudinal cohort study, the clinical records of 67 elderly or middle-aged adult patients who were diagnosed with BPPV at Neurology Clinic, Beijing Chaoyang Hospital affiliated to Capital Medical University between 2013 and 2014. The "Recurrent" and "Non-recurrent" BPPV were respectively defined. Primary data collection included the medical history, blood test and Pittsburgh sleep quality index measurement. Among the total 67 patients after successful treatment, recurrent BPPV is observed in 37.31% patients (n = 25) within 2 years. Among all 11 variables analyzed between recurrent and non-recurrent groups, only the Pittsburgh Sleep Quality Index (PSQI) scores showed significant difference (P quality, sleep latency, sleep duration, the use of sleep-aid medication and daytime dysfunctions (all P quality) had higher risk of BPPV recurrence (OR = 1.17, 95% CI: 1.04-1.32, P= 0.0082). The sleep quality in patients with BPPV recurrence is significantly poorer compared to non-recurrent patients. Our result suggested sleep quality as measured by PSQI is an independent risk factor of BPPV recurrence.

  5. Recurrence of non-Hodgkin's lymphoma

    International Nuclear Information System (INIS)

    Watanabe, Toshikazu; Oguchi, Masahiko; Niibe, Hideo; Horiuchi, Junichi; Kaneta, Koichi; Morita, Kozo; Masaki, Norie; Hayabuchi, Naofumi.

    1988-01-01

    From 1972 to 1982, 563 patients with Stage I and II non-Hodgkin's lymphoma received radiation therapy in the department of radiology which belongs to the JLRTS group. Local control failures were seen in only 5 cases (0.9 %). The regional recurrences were found in 30 cases (5 %). 17 of recurrences occured during the first 5 years. 17 cases had remissions again, and 5 cases had 5 year survivals. (author)

  6. 14 CFR 91.1107 - Recurrent training.

    Science.gov (United States)

    2010-01-01

    ..., as appropriate, including low-altitude windshear training and training on operating during ground... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Recurrent training. 91.1107 Section 91.1107... Management § 91.1107 Recurrent training. (a) Each program manager must ensure that each crewmember receives...

  7. Therapeutic resistance and cancer recurrence mechanisms

    Indian Academy of Sciences (India)

    Cancer recurrence is believed to be one of the major reasons for the failure of cancer treatment strategies. Thisbiological phenomenon could arise from the incomplete eradication of tumour cells after chemo- and radiotherapy.Recent developments in the design of models reflecting cancer recurrence and in vivo imaging ...

  8. 40 CFR 1042.640 - Special provisions for branded engines.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Special provisions for branded engines. 1042.640 Section 1042.640 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Special Compliance Provisions § 1042.640 Special provisions for branded engines. The following provisions...

  9. Recurrent, giant subcutaneous leiomyosarcoma of the thigh

    Directory of Open Access Journals (Sweden)

    Gao Chuanping, MD

    2015-10-01

    Full Text Available We present a case of recurrent, massive subcutaneous leiomyosarcoma involving the left thigh in a 29-year-old male from Madagascar. The patient had earlier undergone local resection of subcutaneous leiomyosarcoma a half year before. After surgical intervention, local recurrence developed at this site and was rapidly growing. The patient was surgically treated with a 2-cm-wide margin local excision in our hospital. The patient has remained recurrence free at 1-year follow-up.

  10. Factors associated with lumbar disc hernia recurrence after microdiscectomy.

    Science.gov (United States)

    Camino Willhuber, G; Kido, G; Mereles, M; Bassani, J; Petracchi, M; Elizondo, C; Gruenberg, M; Sola, C

    Lumbar disc hernias are a common cause of spinal surgery. Hernia recurrence is a prevalent complication. To analyse the risk factors associated with hernia recurrence in patients undergoing surgery in our institution. Lumbar microdiscectomies between 2010 and 2014 were analysed, patients with previous surgeries, extraforaminales and foraminal hernias were excluded. Patients with recurrent hernia were the case group and those who showed no recurrence were the control group. 177 patients with lumbar microdiscectomy, of whom 30 experienced recurrence (16%), and of these 27 were reoperated. Among the risk factors associated with recurrence, we observed a higher rate of disc height, higher percentage of spinal canal occupied by the hernia and presence of degenerative facet joint changes; we observed no differences in sex, body mass index or age. Previous studies show increased disc height and young patients as possible factors associated with recurrence. In our series we found that the higher rate of disc height, the percentage of spinal canal occupied by the hernia and degenerative facet joint changes were associated with hernia recurrence. Copyright © 2017 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.

  11. Recurrent processing during object recognition

    Directory of Open Access Journals (Sweden)

    Randall C. O'Reilly

    2013-04-01

    Full Text Available How does the brain learn to recognize objects visually, and perform this difficult feat robustly in the face of many sources of ambiguity and variability? We present a computational model based on the biology of the relevant visual pathways that learns to reliably recognize 100 different object categories in the face of of naturally-occurring variability in location, rotation, size, and lighting. The model exhibits robustness to highly ambiguous, partially occluded inputs. Both the unified, biologically plausible learning mechanism and the robustness to occlusion derive from the role that recurrent connectivity and recurrent processing mechanisms play in the model. Furthermore, this interaction of recurrent connectivity and learning predicts that high-level visual representations should be shaped by error signals from nearby, associated brain areas over the course of visual learning. Consistent with this prediction, we show how semantic knowledge about object categories changes the nature of their learned visual representations, as well as how this representational shift supports the mapping between perceptual and conceptual knowledge. Altogether, these findings support the potential importance of ongoing recurrent processing throughout the brain's visual system and suggest ways in which object recognition can be understood in terms of interactions within and between processes over time.

  12. Gallium scan in recurrent Hodgkin's disease in children

    International Nuclear Information System (INIS)

    Yeh, S.D.; Benua, R.S.; Tan, C.T.

    1979-01-01

    In 18 of 88 children with biopsy proven and previously untreated Hodgkin's disease, recurrence developed during a period from four to 53 months after therapy (median period, 22 months). In 16 patients in whom gallium scans were performed, 21 positive gallium scans were obtained during 26 episodes of recurrence. Abnormalities were noted in half of them during a period from one to 10 months prior to physical, laboratory, radiographic or histologic confirmation of recurrence (median period about 5 months). We have concluded that the gallium scan is very useful in initial workup and is sensitive in detecting early recurrence in children with Hodgkin's disease. Such scans are indicated when there is clinical suspicion of recurrence, when other modalities are unavailable or when the results of other studies are equivocal

  13. Local recurrence risk after previous salvage mastectomy.

    Science.gov (United States)

    Tanabe, M; Iwase, T; Okumura, Y; Yoshida, A; Masuda, N; Nakatsukasa, K; Shien, T; Tanaka, S; Komoike, Y; Taguchi, T; Arima, N; Nishimura, R; Inaji, H; Ishitobi, M

    2016-07-01

    Breast-conserving surgery is a standard treatment for early breast cancer. For ipsilateral breast tumor recurrence (IBTR) after breast-conserving surgery, salvage mastectomy is the current standard surgical procedure. However, it is not rare for patients with IBTR who have received salvage mastectomy to develop local recurrence. In this study, we examined the risk factors of local recurrence after salvage mastectomy for IBTR. A total of 118 consecutive patients who had histologically confirmed IBTR without distant metastases and underwent salvage mastectomy without irradiation for IBTR between 1989 and 2008 were included from eight institutions in Japan. The risk factors of local recurrence were assessed. The median follow-up period from salvage mastectomy for IBTR was 4.6 years. Patients with pN2 or higher on diagnosis of the primary tumor showed significantly poorer local recurrence-free survival than those with pN0 or pN1 at primary tumor (p mastectomy for IBTR. Further research and validation studies are needed. (UMIN-CTR number UMIN000008136). Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Independent predictors for recurrence of chronic subdural hematoma.

    Science.gov (United States)

    Chon, Kyu-Hyon; Lee, Jong-Myong; Koh, Eun-Jeong; Choi, Ha-Young

    2012-09-01

    Chronic subdural hematoma is characterized by blood in the subdural space that evokes an inflammatory reaction. Numerous factors potentially associated with recurrence of chronic subdural hematoma have been reported, but these factors have not been sufficiently investigated. In this study, we evaluated the independent risk factors of recurrence. We analyzed data for 420 patients with chronic subdural hematoma treated by the standard surgical procedure for hematoma evacuation at our institution. Ninety-two (21.9 %) patients experienced at least one recurrence of chronic subdural hematoma during the study period. We did not identify any significant differences between chronic subdural hematoma recurrence and current antiplatelet therapy. The recurrence rate was 7 % for the homogeneous type, 21 % for the laminar type, 38 % for the separated type, and 0 % for the trabecular type. The rate of recurrence was significantly lower in the homogeneous and trabecular type than in the laminar and separated type. We performed a multivariate logistic regression analysis and found that postoperative midline shifting (OR, 3.6; 95 % CI, 1.618-7.885; p = 0.001), diabetes mellitus (OR, 2.2; 95 % CI, 1.196-3.856; p = 0.010), history of seizure (OR, 2.6; 95 % CI, 1.210-5.430; p = 0.014), width of hematoma (OR, 2.1; 95 % CI, 1.287-3.538; p = 0.003), and anticoagulant therapy (OR, 2.7; 95 % CI, 1.424-6.960; p = 0.005) were independent risk factors for the recurrence of chronic subdural hematoma. We have shown that postoperative midline shifting (≥5 mm), diabetes mellitus, preoperative seizure, preoperative width of hematoma (≥20 mm), and anticoagulant therapy were independent predictors of the recurrence of chronic subdural hematoma. According to internal architecture of hematoma, the rate of recurrence was significantly lower in the homogeneous and the trabecular type than the laminar and separated type.

  15. Recurrent parotitis in children

    Directory of Open Access Journals (Sweden)

    Bhattarai M

    2006-01-01

    Full Text Available Recurrent parotitis is an uncommon condition in children. Its etiological factors have not been proved till date although causes due to genetic inheritance, local autoimmune manifestation, allergy, viral infection and immunodeficiency have been suggested. The exact management of this disorder is not yet standardized, but a conservative approach is preferred and all affected children should be screened for Sjogren′s syndrome and immune deficiency including human immunodeficiency virus. We report a 12 years female child who presented with 12 episodes of non-painful recurrent swellings of the bilateral parotid gland in the past 3 years.

  16. Recurrence in Benign Paroxysmal Positional Vertigo: A Large, Single-Institution Study.

    Science.gov (United States)

    Luryi, Alexander L; Lawrence, Juliana; Bojrab, Dennis I; LaRouere, Michael; Babu, Seilesh; Zappia, John; Sargent, Eric W; Chan, Eleanor; Naumann, Ilka; Hong, Robert S; Schutt, Christopher A

    2018-04-11

    To report rates of recurrence in benign paroxysmal positional vertigo (BPPV) and associated patient and disease factors. Retrospective chart review. Single high-volume otology practice. Patients diagnosed with BPPV from 2007 to 2016 with documented resolution of symptoms. Diagnostic and particle repositioning maneuvers for BPPV. BPPV recurrence, time to recurrence, and ear(s) affected at recurrence. A total of 1,105 patients meeting criteria were identified. Of this population, 37% had recurrence of BPPV in either ear or both ears. Overall same-ear recurrence rate was 28%; 76% of recurrences involved the same ear(s) as initial presentation. Recurrences that occurred after longer disease-free intervals were more likely to involve the opposite ear than early recurrences (p = 0.02). Female sex (40.4% versus 32.7%, p = 0.01) and history of previous BPPV (57.5% versus 32.4%, p diabetes mellitus, and traumatic etiology were not. Approximately, half (56%) of recurrences occurred within 1 year of resolution. A large single-institution study of recurrence in BPPV is presented along with Kaplan-Meier disease-free survival curves. Female sex and history of previous BPPV were associated with increased recurrence, while previously suspected risk factors for recurrence including history of Menière's disease, diabetes, and trauma were not. Remote recurrence is more likely to involve the contralateral ear than early recurrence. These data solidify the expected course of treated BPPV allowing for improved clinical care and patient counseling.

  17. [Selective neck dissection for treating recurrent branchial anomalies].

    Science.gov (United States)

    Chen, Liangsi; Song, Xinhan; Zhang, Siyi; Han, Zhijuan; Luo, Xiaoning; Chen, Shaohua; Zhan, Jiandong

    2011-01-01

    To evaluate the role of selective neck dissection in the treatment of recurrent branchial anomalies. The clinical data of 18 patients with recurrent branchial anomalies were retrospectively analyzed. In accordance with the embryologic and anatomic features of branchial anomalies, different types of selective neck dissection were applied. With dissection and protection of important vessels, nerves and other structures, enbloc resection principles were applied to extirpate branchial lesions, scarrings and inflammatory granuloma during the operation. Of all 18 patients, 16 cases were healed with primary healing, 2 cases with local incision infection were healed after dressing changes. A temporary facial nerve paralysis occurred in 1 case with recurrent first branchial cleft fistula postoperatively, and completely recovered 2 months after operation. A postoperative temporary vocal cord paralysis occurred in 1 case with recurrent fourth branchial cleft fistula, and totally recuperated 1 month after operation. No recurrences were found in all 18 cases with a follow-up period of 12-78 months (average 35 months). Selective neck dissection is a safe and effective surgical procedure for the radical treatment of recurrent branchial anomalies.

  18. An Approach to Measuring Provisions for Collateralised Lending

    OpenAIRE

    Cho-hoi Hui; Tom Fong

    2006-01-01

    Under the framework of Basel II, banks which adopt the internal ratings-based approach will be required to compare their actual provisions with expected losses. Any shortfall (i.e., the expected loss exceeds the provision) should be deducted from capital of the bank. It is therefore important to ensure banks make adequate provisions against expected losses. In addition, both sound policy and the Banking Ordinance require banks to take a forward-looking view of provisions. These requirements r...

  19. To the non-recurrence nature

    International Nuclear Information System (INIS)

    Somsikov, V.

    1999-01-01

    On the example of a hard-disk system the non-recurrence problem have been investigated. Some of the properties of differential equation for the motion of hard-disk system have been analyzed. Using the suggestions of all disk pairs occur simultaneously within a rather small period τ, asymptotic properties of the non-equilibrium hard-disk system when t→∞ have been studied. The explanation of non-recurrence nature have been submitted. (author)

  20. Methods of Services Provision in Slovak Towns

    Directory of Open Access Journals (Sweden)

    Emília Sičáková-Beblavá

    2009-07-01

    Full Text Available This article deals with the methods of services provision in Slovak towns.  It addresses decision-making concerning selected services provision, based on a transaction cost economic model. The article looks at five types of services from that point of view. These are core services, i.e., services that are provided in most Slovak towns, thereby allowing outcomes of decision-making to be compared, and services which can be outsourced according to transaction cost theory. Findings partially confirm the hypothesis: Slovak towns do outsource, though “insourcing” moderately prevails. However, a comparison of several research studies in the area indicates a trend towards higher outsourcing of such local services provision.  The findings show that public bodies do not always select the most suitable methods of services provision, as suggested by the transaction costs theory (the Brown-Potoski model. This indicates that it is not only economic models that influence decision-making concerning the organization of services provision in the Slovak towns.

  1. Implementing the optimal provision of ecosystem services.

    Science.gov (United States)

    Polasky, Stephen; Lewis, David J; Plantinga, Andrew J; Nelson, Erik

    2014-04-29

    Many ecosystem services are public goods whose provision depends on the spatial pattern of land use. The pattern of land use is often determined by the decisions of multiple private landowners. Increasing the provision of ecosystem services, though beneficial for society as a whole, may be costly to private landowners. A regulator interested in providing incentives to landowners for increased provision of ecosystem services often lacks complete information on landowners' costs. The combination of spatially dependent benefits and asymmetric cost information means that the optimal provision of ecosystem services cannot be achieved using standard regulatory or payment for ecosystem services approaches. Here we show that an auction that sets payments between landowners and the regulator for the increased value of ecosystem services with conservation provides incentives for landowners to truthfully reveal cost information, and allows the regulator to implement the optimal provision of ecosystem services, even in the case with spatially dependent benefits and asymmetric information.

  2. 22 CFR 226.48 - Contract provisions.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Contract provisions. 226.48 Section 226.48 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Procurement Standards § 226.48 Contract provisions. The...

  3. 48 CFR 11.107 - Solicitation provision.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Solicitation provision. 11... transaction-based reporting method to report its use of voluntary consensus standards to the National... Use of Voluntary Consensus Standards and in Conformity Assessment Activities”). Use of the provision...

  4. Recurrent loss of specific introns during angiosperm evolution.

    Directory of Open Access Journals (Sweden)

    Hao Wang

    2014-12-01

    Full Text Available Numerous instances of presence/absence variations for introns have been documented in eukaryotes, and some cases of recurrent loss of the same intron have been suggested. However, there has been no comprehensive or phylogenetically deep analysis of recurrent intron loss. Of 883 cases of intron presence/absence variation that we detected in five sequenced grass genomes, 93 were confirmed as recurrent losses and the rest could be explained by single losses (652 or single gains (118. No case of recurrent intron gain was observed. Deep phylogenetic analysis often indicated that apparent intron gains were actually numerous independent losses of the same intron. Recurrent loss exhibited extreme non-randomness, in that some introns were removed independently in many lineages. The two larger genomes, maize and sorghum, were found to have a higher rate of both recurrent loss and overall loss and/or gain than foxtail millet, rice or Brachypodium. Adjacent introns and small introns were found to be preferentially lost. Intron loss genes exhibited a high frequency of germ line or early embryogenesis expression. In addition, flanking exon A+T-richness and intron TG/CG ratios were higher in retained introns. This last result suggests that epigenetic status, as evidenced by a loss of methylated CG dinucleotides, may play a role in the process of intron loss. This study provides the first comprehensive analysis of recurrent intron loss, makes a series of novel findings on the patterns of recurrent intron loss during the evolution of the grass family, and provides insight into the molecular mechanism(s underlying intron loss.

  5. Recurrent hepatoblastoma with localization by PET-CT

    Energy Technology Data Exchange (ETDEWEB)

    Figarola, Maria S.; McQuiston, Samuel A. [University of South Alabama, Department of Radiology, Mobile, AL (United States); Wilson, Felicia [University of South Alabama, Pediatric Hematology-Oncology, Mobile, AL (United States); Powell, Randall [University of South Alabama, Surgery Department, Mobile, AL (United States)

    2005-12-01

    Hepatoblastoma is the most common primary liver tumor in children, accounting for 79% of pediatric liver malignancies in children younger than 15 years, with most cases reported before the age of 5 years. Localization of primary and recurrent disease is necessary for appropriate clinical decision-making and treatment. We present a case of recurrent hepatoblastoma heralded by rising alpha-fetoprotein levels. After unsuccessful localization by conventional CT and MRI, positron emission tomography CT imaging localized the sites of recurrence. (orig.)

  6. Recurrence plots of exchange rates of currencies

    OpenAIRE

    Sparavigna, Amelia Carolina

    2014-01-01

    Used to investigate the presence of distinctive recurrent behaviours in natural processes, the recurrence plots can be applied to the analysis of economic data, and, in particular, to the characterization of exchange rates of currencies too. In this paper, we will show that these plots are able to characterize the periods of oscillation and random walk of currencies and enhance their reply to news and events, by means of texture transitions. The examples of recurrence plots given here are obt...

  7. Recurrent symptoms after fundoplication with a negative pH study--recurrent reflux or functional heartburn?

    Science.gov (United States)

    Thompson, Sarah K; Cai, Wang; Jamieson, Glyn G; Zhang, Alison Y; Myers, Jennifer C; Parr, Zoe E; Watson, David I; Persson, Jenny; Holtmann, Gerald; Devitt, Peter G

    2009-01-01

    A small cohort of patients present after antireflux surgery complaining of recurrent heartburn. Over two thirds of these patients will have a negative 24-h pH study. The aim of our study is to determine whether these patients have an associated functional disorder or abnormal cytokine activity and to examine the reproducibility of pH testing. A prospective analysis was carried out on a cohort of patients who had undergone a fundoplication and postoperative pH testing for recurrent heartburn: group A--patients with recurrent heartburn and a negative 24-h pH study and group B (control group)--patients with recurrent heartburn and a positive pH study. Questionnaires, a blood sample, and repeat pH testing were completed. Sixty-nine patients were identified. Group A's depression score (8.6 +/- 4.1) was significantly higher than group B's (5.9 +/- 4.2; P = 0.03). Cytokine levels were similar in both groups. Forty-seven of 49 (96%) patients who underwent repeat pH testing had a negative study. Symptom-reflux correlation was highly significant (P heartburn and a negative pH study have associated functional or psychiatric comorbidities such as depression. Reproducibility of 24-h pH testing in these patients is excellent.

  8. A Case of Recurrent Respiratory Papillomatosis Successfully Removed Via Endoscopic Argon Plasma Coagulation (APC) With No Evidence of Recurrence.

    Science.gov (United States)

    Wong, J L; Tie, S T; Lee, J; Kannan, S K; Rashid Ali, M R; Ibrahim, A; Abdul Rahman, J A

    2014-08-01

    Recurrent respiratory papillomatosis (RRP) is a benign disease caused by the human papilloma virus (HPV), characterized by the formation of recurrent, epithelial neoplastic lesions in the airways. While benign, they can cause significant airway obstruction in some cases. Difficulties in treatment arise from the recurrent nature of the lesions despite repeated procedures. Other known procedures that result in deep tissue damage also cause unacceptable collateral damage to the underlying airway mucosa. We describe a case of recurrent papillomatosis that was successfully treated with argon plasma coagulation ( APC) when laser and electrocautery ablation had failed in the past. After the papillomatasis was treated with APC, there is no recurrence on repeat scope at 4 months and 9 months after the initial procedure. The procedure was done as a day case and there is no complication from the procedure. The property of the APC that allows it to cause only superficial thermal damage to the tissue makes it a suitable adjunct therapy to the treatment of papillomas, which are usually superficial lesions.

  9. 7 CFR 457.148 - Fresh market pepper crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Fresh market pepper crop insurance provisions. 457.148... pepper crop insurance provisions. The fresh market pepper crop insurance provisions for the 1999 and... Fresh Market Pepper Crop Provisions If a conflict exists among the policy provisions, the order of...

  10. Postoperative recurrence after VATS for spontaneous pneumothorax

    International Nuclear Information System (INIS)

    Katsuno, Gotaro; Tsumura, Makoto; Kokudo, Yasutaka; Muraoka, Atsushi; Tsuruno, Masaki

    2003-01-01

    A total of 88 cases of 81 patients with spontaneous pneumothorax treated at the hospital from March 1992 to August 2001 were subjected to a study of examining preoperative chest CT and thoracographic findings from the standpoint of postoperative recurrence. Preoperative chest CT and thoracography were conducted in 82 cases and 41 cases (including 25 cases with continuous air leakage), respectively. Eight (9.1%) patients developed recurrence of pneumothorax, and three patients of them underwent reoperation. Considering the intraoperative findings, newly formed bullae appeared to be a cause of recurrence. Resulting from these examinations, we conclude that it is difficult to predict the risk factor for postoperative recurrence at this time, in addition, it is important that the area of air leakage can be confirmed by thoracoscopic findings. (author)

  11. 7 CFR 457.166 - Blueberry crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Blueberry crop insurance provisions. 457.166 Section... CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.166 Blueberry crop insurance provisions. The Blueberry Crop Insurance Provisions for the 2005 and succeeding crop years are as follows...

  12. 40 CFR 141.76 - Recycle provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Recycle provisions. 141.76 Section 141...) NATIONAL PRIMARY DRINKING WATER REGULATIONS Filtration and Disinfection § 141.76 Recycle provisions. (a... recycle spent filter backwash water, thickener supernatant, or liquids from dewatering processes must meet...

  13. Risk factors for recurrent otitis media with effusion

    Directory of Open Access Journals (Sweden)

    Baljošević Ivan

    2017-01-01

    Full Text Available Background/Aim. Otitis media with effusion (OME is a common disease among the children aged from 6 months to 4 years, but recurrences are common after the extraction of ventilation tubes. The aim of the study was to determine the risk factors for recurrent OME after extraction of ventilation tubes. Methods. The research was a prospective study with 305 children aged 0 to 10 years with OME. Forty three (14% of them had recurrent OME. We analyzed the factors that could lead to the redevelopment of the disease after extrusion of the tubes. Results. It was found that the majority of children with recurrent disease was between the ages of 5 to 7 years (56% and had allergy in significantly higher rate than children without recurrence. In most cases (37.7%, the retention time of ventilating tube was above 10 months and the recurrent disease was diagnosed in 46.5% cases within a period of 10 to 12 months after extrusion of tubes. Conclusion. Children with OME and after ventilation tube extrusion need to be followed up for 1 year after the removal of tubes. It is necessary to inform the parents that the disease can recur. Children in the kindergarten, in preschool age and with a respiratory allergy had higher possibility for recurrent OME.

  14. Bezlotoxumab: A Review in Preventing Clostridium difficile Infection Recurrence.

    Science.gov (United States)

    Deeks, Emma D

    2017-10-01

    Bezlotoxumab (Zinplava™) is a fully human monoclonal antibody against Clostridium difficile toxin B indicated for the prevention of C. difficile infection (CDI) recurrence in patients with a high recurrence risk. It is the first agent approved for recurrence prevention and is administered as a single intravenous infusion in conjunction with standard-of-care (SoC) antibacterial treatment for CDI. In well-designed, placebo-controlled, phase 3 trials (MODIFY 1 and 2), a single infusion of bezlotoxumab, given in combination with SoC antibacterial therapy for CDI in adults, was effective in reducing CDI recurrence in the 12 weeks post-treatment, with this benefit being seen mainly in the patients at high recurrence risk. Bezlotoxumab did not impact the efficacy of the antibacterials being used to treat the CDI and, consistent with its benefits on CDI recurrence, appeared to reduce the need for subsequent antibacterials, thus minimizing further gut microbiota disruption. Longer term, there were no further CDI recurrences over 12 months' follow-up among patients who had received bezlotoxumab in MODIFY 2 and entered an extension substudy. Bezlotoxumab has low immunogenicity and is generally well tolerated, although the potential for heart failure in some patients requires consideration; cost-effectiveness data for bezlotoxumab are awaited with interest. Thus, a single intravenous infusion of bezlotoxumab during SoC antibacterial treatment for CDI is an emerging option for reducing CDI recurrence in adults at high risk of recurrence.

  15. Recurrent shoulder dystocia: is it predictable?

    Science.gov (United States)

    Kleitman, Vered; Feldman, Roi; Walfisch, Asnat; Toledano, Ronen; Sheiner, Eyal

    2016-11-01

    To examine the course and outcome of deliveries occurring in women who previously experienced shoulder dystocia. In addition, recurrent shoulder dystocia risk factors were assessed. A retrospective cohort analysis comparing all singleton deliveries with and without shoulder dystocia in their preceding delivery was conducted. Independent predictors of recurrent shoulder dystocia were investigated using a multiple logistic regression model. Of the 201,422 deliveries included in the analysis, 307 occurred in women with a previous shoulder dystocia (0.015 %). Women with a history of shoulder dystocia were more likely to be older, experienced higher rates of gestational diabetes mellitus, polyhydramnios, prolonged second stage, operative delivery and macrosomia (>4000 g) in the following delivery. Previous shoulder dystocia was found to be an independent risk factor for recurrent shoulder dystocia (OR = 6.1, 95 % CI 3.2-11.8, p value dystocia is an independent risk factor for recurrent shoulder dystocia. Deliveries in women with a history of shoulder dystocia are characterized by higher rates of operative delivery, prolonged second stage of labor and macrosomia.

  16. Recurrent Novae — A Review

    Directory of Open Access Journals (Sweden)

    K. Mukai

    2015-02-01

    Full Text Available In recent years, recurrent nova eruptions are often observed very intensely in wide range of wavelengths from radio to optical to X-rays. Here I present selected highlights from recent multi-wavelength observations. The enigma of T Pyx is at the heart of this paper. While our current understanding of CV and symbiotic star evolution can explain why certain subset of recurrent novae have high accretion rate, that of T Pyx must be greatly elevated compared to the evolutionary mean. At the same time, we have extensive data to be able to estimate how the nova envelope was ejected in T Pyx, and it turns to be a rather complex tale. One suspects that envelope ejection in recurrent and classical novae in general is more complicated than the textbook descriptions. At the end of the review, I will speculate that these two may be connected.

  17. 7 CFR 457.162 - Nursery crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Nursery crop insurance provisions. 457.162 Section 457... CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.162 Nursery crop insurance provisions. The Nursery Crop Insurance Provisions for the 2006 and succeeding crop years are as follows: FCIC...

  18. 7 CFR 457.123 - Almond crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Almond crop insurance provisions. 457.123 Section 457... CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.123 Almond crop insurance provisions. The Almond Crop Insurance Provisions for the 2008 and succeeding crop years are as follows: FCIC...

  19. Recurrent Admissions for Diabetic Foot Complications

    Directory of Open Access Journals (Sweden)

    Ang CL

    2013-07-01

    Full Text Available Diabetic foot complications are a significant source of morbidity and mortality. Patients who undergo recurrent admissions for the same diabetic foot problems represent a difficult subgroup to treat. From July 2007 to June 2008, there were 38 such patients who were admitted recurrently. Eighteen patients (47% were re-admitted because of previous refusal of surgical treatment. Eighteen patients (47% received treatment as necessary but were still readmitted for recurrent infection at the same wound site. Assessment of patients’ compliance to outpatient treatment was found to be generally lacking. As a significant proportion were re-admitted because of previous refusal of surgery, a trained counselor may be suitable in counselling patients for debridement or amputation surgery.

  20. Prevention of Recurrent Staphylococcal Skin Infections

    Science.gov (United States)

    Creech, C. Buddy; Al-Zubeidi, Duha N.; Fritz, Stephanie A.

    2015-01-01

    Synopsis Staphylococcus aureus infections pose a significant health burden. The emergence of community-associated methicillin-resistant S. aureus has resulted in an epidemic of skin and soft tissue infections (SSTI), and many patients experience recurrent SSTI. As S. aureus colonization is associated with subsequent infection, decolonization is recommended for patients with recurrent SSTI or in settings of ongoing transmission. S. aureus infections often cluster within households and asymptomatic carriers serve as reservoirs for transmission; therefore, a household approach to decolonization is more effective than measures performed by individuals alone. Other factors, such as environmental surface contamination, may also be considered. Novel strategies for the prevention of recurrent SSTI are needed. PMID:26311356

  1. 22 CFR 63.9 - General provisions.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false General provisions. 63.9 Section 63.9 Foreign Relations DEPARTMENT OF STATE PUBLIC DIPLOMACY AND EXCHANGES PAYMENTS TO AND ON BEHALF OF PARTICIPANTS IN THE INTERNATIONAL EDUCATIONAL AND CULTURAL EXCHANGE PROGRAM § 63.9 General provisions. The following...

  2. 30 CFR 847.2 - General provisions.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false General provisions. 847.2 Section 847.2 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PERMANENT PROGRAM... court of competent jurisdiction enters a judgment against or convicts a person under these provisions...

  3. Surgical Management of Recurrent Odontogenic Keratocyst

    OpenAIRE

    Semi, Ravinder Singh; Thapliyal, G. K.; Menon, Suresh

    2010-01-01

    The odontogenic keratocyst is a distinct entity arising from odontogenic epithelium. The unique histopathological appearance and the propensity for recurrence has made it management controversial in terms of the conservatism to be followed. This article describes the management of a case of recurrent odontogenic keratocyst with an aggressive therapy being adopted due to the nature of the pathology.

  4. Aggressive Regimens for Multidrug-Resistant Tuberculosis Reduce Recurrence

    Science.gov (United States)

    Franke, Molly F.; Appleton, Sasha C.; Mitnick, Carole D.; Furin, Jennifer J.; Bayona, Jaime; Chalco, Katiuska; Shin, Sonya; Murray, Megan; Becerra, Mercedes C.

    2013-01-01

    Background. Recurrent tuberculosis disease occurs within 2 years in as few as 1% and as many as 29% of individuals successfully treated for multidrug-resistant (MDR) tuberculosis. A better understanding of treatment-related factors associated with an elevated risk of recurrent tuberculosis after cure is urgently needed to optimize MDR tuberculosis therapy. Methods. We conducted a retrospective cohort study among adults successfully treated for MDR tuberculosis in Peru. We used multivariable Cox proportional hazards regression analysis to examine whether receipt of an aggressive MDR tuberculosis regimen for ≥18 months following sputum conversion from positive to negative was associated with a reduced rate of recurrent tuberculosis. Results. Among 402 patients, the median duration of follow-up was 40.5 months (interquartile range, 21.2–53.4). Receipt of an aggressive MDR tuberculosis regimen for ≥18 months following sputum conversion was associated with a lower risk of recurrent tuberculosis (hazard ratio, 0.40 [95% confidence interval, 0.17–0.96]; P = .04). A baseline diagnosis of diabetes mellitus also predicted recurrent tuberculosis (hazard ratio, 10.47 [95% confidence interval, 2.17–50.60]; P = .004). Conclusions. Individuals who received an aggressive MDR tuberculosis regimen for ≥18 months following sputum conversion experienced a lower rate of recurrence after cure. Efforts to ensure that an aggressive regimen is accessible to all patients with MDR tuberculosis, such as minimization of sequential ineffective regimens, expanded drug access, and development of new MDR tuberculosis compounds, are critical to reducing tuberculosis recurrence in this population. Patients with diabetes mellitus should be carefully managed during initial treatment and followed closely for recurrent disease. PMID:23223591

  5. Locoregional recurrence following maxillectomy: implications for microvascular reconstruction.

    Science.gov (United States)

    Likhterov, Ilya; Fritz, Michael A; El-Sayed, Ivan H; Rahul Seth; Rayess, Hani M; Knott, P Daniel

    2017-11-01

    Reconstruction of maxillectomy defects offers potential quality-of-life improvement, although cavity coverage may impact surveillance of recurrent malignancy. We describe the pattern of postmaxillectomy locoregional recurrence. Retrospective review. Patients from 2001 to 2011 at the University of California, San Francisco and the Cleveland Clinic. Among 75 patients with malignancy resulting in partial or total maxillectomy, 57 were treated with obturators and 18 underwent reconstructive surgery. Disease recurrence occurred primarily locally (19 of 22 cases of recurrence, 25% of the cohort) at a mean of 17 months postoperatively. Recurrence was associated with T4 disease, positive margins, and surveillance imaging. Four (5.3%) patients required flap mobilization/obturator removal to obtain biopsy. Salvage surgery was attempted in 13 of the 19 cases with recurrent disease (68%) and was successful in six (46%) patients. Of these, five patients initially had Brown type 1 or type 2 defects. The free flap had to be revised in one (1.3%) patient to achieve successful salvage. Maxillectomy provides good long-term locoregional oncologic control, with cure being correlated to disease stage at presentation and negative margins after initial surgery. Patients with recurrent disease whose initial resection resulted in a Brown class 3 defect or greater were rarely successfully salvaged. Surveillance is best performed with a combination of physical exam and imaging. Obturator removal/flap mobilization rarely impedes the diagnosis of recurrent disease, and either modality should be offered to appropriate patients in the primary setting if significant quality-of-life improvement is likely. 4. Laryngoscope, 127:2534-2538, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

  6. Social Housing Provision in Copenhagen

    DEFF Research Database (Denmark)

    Tsenkova, Sasha; Vestergaard, Hedvig

    -profit housing providers, and a wide range of fiscal and regulatory instruments enhancing the competitive performance of the social housing sector. The research analyses recent housing policy measures and their impact on new social housing provision in Copenhagen. The emphasis is on the mix of housing policy......The paper provides an overview of trends and processes of change affecting new social housing provision in Denmark with a focus on Copenhagen. The local responses are reviewed within the context of changes to the unitary national housing system that functions with a robust range of private and non...... instruments implemented in three major policy domains-fiscal, financial and regulatory-to promote the production of new social housing. The system of new social housing provision is examined as a dynamic process of interaction between public and private institutions defining housing policy outcomes...

  7. Temperature, age, and recurrence of febrile seizure

    NARCIS (Netherlands)

    M. van Stuijvenberg (Margriet); E.W. Steyerberg (Ewout); G. Derksen-Lubsen (Gerarda); H.A. Moll (Henriëtte)

    1998-01-01

    textabstractOBJECTIVE: Prediction of a recurrent febrile seizure during subsequent episodes of fever. DESIGN: Study of the data of the temperatures, seizure recurrences, and baseline patient characteristics that were collected at a randomized placebo controlled trial of ibuprofen

  8. The content of recurrent dreams in young adolescents.

    Science.gov (United States)

    Gauchat, Aline; Séguin, Jean R; McSween-Cadieux, Esther; Zadra, Antonio

    2015-12-01

    Studies on children's recurrent dreams have been largely anecdotal and based on adults' recollections of dreams experienced during childhood. We collected 102 reports of recurrent dreams from a sample of young adolescents aged between 11 and 15years and scored the narratives using a range of content measures, including in relation to the threat simulation theory (TST) of dreaming. The most frequently reported themes involved confrontations with monsters or animals, followed by physical aggressions, falling and being chased. Recurrent dreams were more likely to include negative content elements than positive elements. Only half of the recurrent dreams contained threatening elements and their analysis provided mixed support for the TST. Differences between the content of recurrent dreams reported by young adolescent versus adults are discussed as are possible sex effects and key issues that remain to be addressed by future research. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Multiplex Recurrence Networks

    Science.gov (United States)

    Eroglu, Deniz; Marwan, Norbert

    2017-04-01

    The complex nature of a variety of phenomena in physical, biological, or earth sciences is driven by a large number of degrees of freedom which are strongly interconnected. Although the evolution of such systems is described by multivariate time series (MTS), so far research mostly focuses on analyzing these components one by one. Recurrence based analyses are powerful methods to understand the underlying dynamics of a dynamical system and have been used for many successful applications including examples from earth science, economics, or chemical reactions. The backbone of these techniques is creating the phase space of the system. However, increasing the dimension of a system requires increasing the length of the time series in order get significant and reliable results. This requirement is one of the challenges in many disciplines, in particular in palaeoclimate, thus, it is not easy to create a phase space from measured MTS due to the limited number of available obervations (samples). To overcome this problem, we suggest to create recurrence networks from each component of the system and combine them into a multiplex network structure, the multiplex recurrence network (MRN). We test the MRN by using prototypical mathematical models and demonstrate its use by studying high-dimensional palaeoclimate dynamics derived from pollen data from the Bear Lake (Utah, US). By using the MRN, we can distinguish typical climate transition events, e.g., such between Marine Isotope Stages.

  10. Recurrence quantification analysis theory and best practices

    CERN Document Server

    Jr, Jr; Marwan, Norbert

    2015-01-01

    The analysis of recurrences in dynamical systems by using recurrence plots and their quantification is still an emerging field.  Over the past decades recurrence plots have proven to be valuable data visualization and analysis tools in the theoretical study of complex, time-varying dynamical systems as well as in various applications in biology, neuroscience, kinesiology, psychology, physiology, engineering, physics, geosciences, linguistics, finance, economics, and other disciplines.   This multi-authored book intends to comprehensively introduce and showcase recent advances as well as established best practices concerning both theoretical and practical aspects of recurrence plot based analysis.  Edited and authored by leading researcher in the field, the various chapters address an interdisciplinary readership, ranging from theoretical physicists to application-oriented scientists in all data-providing disciplines.

  11. Recurrent urinary tract infections in women.

    Science.gov (United States)

    Aydin, Abdullatif; Ahmed, Kamran; Zaman, Iftikhar; Khan, Muhammad Shamim; Dasgupta, Prokar

    2015-06-01

    Recurrent urinary tract infections (UTIs) are more common in women and are frequently defined as ≥2 episodes in the last 6 months or ≥3 episodes in the last 12 months. In a primary care setting, 53 % of women above the age of 55 years and 36 % of younger women report a recurrence within 1 year. Thus, management and prevention of recurrent UTI is of utmost significance. This review aims to highlight the latest research in prevention strategies and suggest a management pathway. A search was conducted on MEDLINE, Embase and the Cochrane Database of Systematic Reviews databases for the latest systematic reviews and high-quality randomized controlled trials. Special emphasis was placed on the remit "recurrent" and strongly adhered to. Furthermore, a Google search was conducted for current guidelines on the management of UTIs. Current prevention strategies include eliminating risk factors that increase the risk of acquiring recurrent UTI and continuous, post-coital and self-initiated antimicrobial prophylaxis. Other prospective preventative strategies, currently under trial, include use of vaccinations, D-mannose and lactobacillus (probiotics). Although risk factors should be identified and addressed accordingly, individualized antibiotic prophylaxis remains the most effective method of management. Non-antibiotic prevention strategies such as cranberry, vitamin C and methenamine salts lack strong evidence to be introduced as routine management options and as alternatives to antibiotics. Based on current evidence and guidelines, a management pathway is recommended. Emerging therapies require further evaluation before they can be recommended.

  12. A fuzzy multi-objective model for capacity allocation and pricing policy of provider in data communication service with different QoS levels

    Science.gov (United States)

    Pan, Wei; Wang, Xianjia; Zhong, Yong-guang; Yu, Lean; Jie, Cao; Ran, Lun; Qiao, Han; Wang, Shouyang; Xu, Xianhao

    2012-06-01

    Data communication service has an important influence on e-commerce. The key challenge for the users is, ultimately, to select a suitable provider. However, in this article, we do not focus on this aspect but the viewpoint and decision-making of providers for order allocation and pricing policy when orders exceed service capacity. It is a multiple criteria decision-making problem such as profit and cancellation ratio. Meanwhile, we know realistic situations in which much of the input information is uncertain. Thus, it becomes very complex in a real-life environment. In this situation, fuzzy sets theory is the best tool for solving this problem. Our fuzzy model is formulated in such a way as to simultaneously consider the imprecision of information, price sensitive demand, stochastic variables, cancellation fee and the general membership function. For solving the problem, a new fuzzy programming is developed. Finally, a numerical example is presented to illustrate the proposed method. The results show that it is effective for determining the suitable order set and pricing policy of provider in data communication service with different quality of service (QoS) levels.

  13. 9 CFR 93.916 - Special provisions.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Special provisions. 93.916 Section 93... § 93.916 Special provisions. (a) Slaughter. Live VHS-regulated fish from VHS-regulated regions may be... establishment discharges its waste water to a municipal sewage system that includes waste water disinfection...

  14. 12 CFR 1261.2 - General provisions.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false General provisions. 1261.2 Section 1261.2 Banks and Banking FEDERAL HOUSING FINANCE AGENCY FEDERAL HOME LOAN BANKS FEDERAL HOME LOAN BANK DIRECTORS Federal Home Loan Bank Boards of Directors: Eligibility and Elections § 1261.2 General provisions. (a...

  15. Recurrent meningitis--a review of current literature.

    Science.gov (United States)

    Janocha-Litwin, Justyna; Simon, Krzysztof

    2013-01-01

    The paper discusses epidemiology, aetiology and the most important predisposing factors associated with recurrent meningitis, as well as the possibilities to prevent this particularly challenging clinical problem. The frequency of recurrent meningitis is estimated to be 2-9%. However, the case fatality is lower compared to a single episode of meningitis. The main causes of recurrent meningitis are considered to be: head injury, congenital or acquired (post-traumatic or post-surgical) cranial or spinal defects, chronic intracranial inflammation, complement system dysfunction, as well as congenital and acquired humoral or cellular immunodeficiency.

  16. Recurrent Guillain-Barre Syndrome- A Case Report

    Directory of Open Access Journals (Sweden)

    Dilesha WL

    2015-05-01

    Full Text Available Guillain-Barre syndrome (GBS manifests as acute flaccid weakness of limbs, and is considered a monophasic illness. But recurrences have been reported. Published case studies suggest that 1- 5% of patients who had GBS will have recurrent attacks. We describe a 66-year-old lady who presented with acute onset descending, symmetrical, areflexic, flaccid quadriparesis that progressed to respiratory failure. She had a history of GBS five years back of which she had made a complete recovery with no residual weakness. The diagnosis of recurrent GBS was made.

  17. Children's Rights, School Exclusion and Alternative Educational Provision

    Science.gov (United States)

    McCluskey, Gillean; Riddell, Sheila; Weedon, Elisabet

    2015-01-01

    This paper examines findings from a recent study in Wales of school exclusion and alternative educational provision. Many, but not all, children in alternative provision have been excluded from school. The most recent statistics reveal that nearly 90% of pupils in alternative provision have special educational needs, nearly 70% are entitled to…

  18. Green Network Planning Model for Optical Backbones

    DEFF Research Database (Denmark)

    Gutierrez Lopez, Jose Manuel; Riaz, M. Tahir; Jensen, Michael

    2010-01-01

    on the environment in general. In network planning there are existing planning models focused on QoS provisioning, investment minimization or combinations of both and other parameters. But there is a lack of a model for designing green optical backbones. This paper presents novel ideas to be able to define......Communication networks are becoming more essential for our daily lives and critically important for industry and governments. The intense growth in the backbone traffic implies an increment of the power demands of the transmission systems. This power usage might have a significant negative effect...

  19. Bladder versus renal bacteriuria during pregnancy: recurrence after treatment.

    Science.gov (United States)

    Leveno, K J; Harris, R E; Gilstrap, L C; Whalley, P J; Cunningham, F G

    1981-02-15

    Localization of bacteriuria has been shown to correlate with the pattern of recurrence after treatment. The immunofluorescent technique was used to localize infection in 233 pregnant women with asymptomatic bacteriuria to determine whether this would identify those who were at greater risk for recurrence. In both an indigent and a military population, the incidence of renal bacteriuria was 42%. Regardless of the site of infection, after one course of short-term (10-day) or long-term (21-day) antimicrobial therapy, almost two thirds of these women were abacteriuric for the remainder of gestation. Women given short-term treatment were more likely to have a recurrence within 2 weeks of completion of therapy than were women given long-term therapy (P less than 0.001). Moreover, these early recurrences were more frequent in women given short-term treatment for renal bacteriuria (P less than 0.05). Conversely, recurrences 6 or more weeks after completion of therapy, and regardless of site of infection, were more common in women given long-term treatment (P less than 0.01). Although the timing of recurrence varied significantly in relation to duration of treatment and site of infection, the ultimate risk of recurrence was not related to either. The conclusion is that localization of asymptomatic bacteriuria does not contribute to the management of pregnant women, since overall recurrence rates are independent of the site of infection.

  20. The Impacts of Peptic Ulcer on Stroke Recurrence.

    Science.gov (United States)

    Xu, Zongliang; Wang, Ling; Lin, Ying; Wang, Zhaojun; Zhang, Yun; Li, Junrong; Li, Shenghua; Ye, Zusen; Yuan, Kunxiong; Shan, Wanying; Liu, Xinfeng; Fan, Xinying; Xu, Gelin

    2018-04-10

    Peptic ulcer has been associated with an increased risk of stroke. This study aimed to evaluate the impacts of peptic ulcer on stroke recurrence and mortality. Patients with first-ever ischemic stroke were retrospectively confirmed with or without a history of peptic ulcer. The primary end point was defined as fatal and nonfatal stroke recurrence. Risks of 1-year fatal and nonfatal stroke recurrence were analyzed with the Kaplan-Meier method. Predictors of fatal and nonfatal stroke recurrence were evaluated with the Cox proportional hazards model. Among the 2577 enrolled patients with ischemic stroke, 129 (5.0%) had a history of peptic ulcer. The fatal and nonfatal stroke recurrence within 1 year of the index stroke was higher in patients with peptic ulcer than in patients without peptic ulcer (12.4% versus 7.2%, P = .030). Cox proportional hazards model detected that age (hazard ratio [HR] = 1.018, 95% confidence interval [CI] 1.005-1.031, P = .008), hypertension (HR = 1.397, 95% CI 1.017-1.918, P = .039), and history of peptic ulcer (HR = 1.853, 95% CI 1.111-3.091, P = .018) were associated with stroke recurrence. Ischemic stroke patients with peptic ulcer may have an increased risk of stroke recurrence. The results emphasize the importance of appropriate prevention and management of peptic ulcer for secondary stroke prevention. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  1. 12 CFR 931.9 - Transition provision.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Transition provision. 931.9 Section 931.9 Banks and Banking FEDERAL HOUSING FINANCE BOARD FEDERAL HOME LOAN BANK RISK MANAGEMENT AND CAPITAL STANDARDS FEDERAL HOME LOAN BANK CAPITAL STOCK § 931.9 Transition provision. (a) In general. Each Bank shall comply...

  2. Recurrent gastric lactobezoar in an infant

    OpenAIRE

    Castro, Leonor; Berenguer, Alberto; Pilar, Carla; Gon?alves, Rute; Nunes, Jos? L.

    2014-01-01

    Lactobezoars are a type of bezoar composed of undigested milk and mucus. The aetiology is likely multifactorial, being classically described in association with pre-term, low-birth weight infants fed with hyperconcentrated formula. The authors present a case of lactobezoar recurrence in a pre-term infant with oesophageal atresia. To our knowledge, this is the first report of recurrence of lactobezoar.

  3. Frequency of Herpes Zoster Recurrence in Central District of Korea.

    Science.gov (United States)

    Ha, Jae Won; Lee, Jin Yong; Her, Young; Kim, Chul Woo; Kim, Sang Seok

    2017-10-01

    Herpes zoster is characterized by unilateral grouped vesicles along the distribution of a dermatome. A global recurrence rate as low as 0.5%∼6.2% has been reported for herpes zoster. The recurrence of herpes zoster is higher in immunocompromised patients and older patients. The purpose of this study is to assess the frequency of herpes zoster recurrence and factors that can influence its recurrence. From January 2005 to December 2015, 14,343 patients with herpes zoster were enrolled in this study. The patients were diagnosed at Hallym University Medical Centers and Kangwon National University Hospital in Seoul, Gyeonggi, and Gangwon. Herpes zoster recurrence and patient characteristics were surveyed by medical record review and a telephonic survey. The overall frequency of herpes zoster recurrence was 1.18%. The frequency of recurrence was higher in women than in men. It was also higher in patients aged 50∼70 years than in patients who were younger or older than this. Additionally, we assessed that the frequency of recurrence was statistically higher in patients with a compromised immune system and in patients who experienced longer lasting pain during their first episode. The frequency of herpes zoster recurrence is more common in women, older age, patient with longer pain duration and immunocompromised patients.

  4. The CT features of recurrent laryngeal nerve paralysis

    International Nuclear Information System (INIS)

    Wu Bin; Peng Weijun; Gu Yajia; Yang Tianxi; Wang Hongshi

    2006-01-01

    Objective: To describe the CT appearance of recurrent laryngeal nerve paralysis, discuss the anatomic and pathologic basis of this paralysis, and evaluate CT diagnosis. Methods: 32 cases of recurrent laryngeal nerve paralysis clinical confirmed were analyzed retrospectively. All of these patients had the CT scans from the level of hyoid bone to the upper thorax, the slice and interval are 5 mm. Results: CT findings of recurrent laryngeal nerve paralysis included: oblique of aryepiglottic fold, dislocation of arytenoid cartilage and cricoarytenoid joint, dilation and relaxation of piriform sinus for 27 cases (84.4%); wide and asymmetrical ventricle of larynx for 16 cases (50.0%); asymmetrical and fix of vocal fold for 11 cases (34.4%) et al. Conclusion: The recurrent laryngeal nerve innervate all the intrinsic muscles of the larynx except cricothyroid muscle, paralysis of the nerve leads to atrophy of related muscles. CT scan demonstrate the larynx morphologic changes of recurrent nerve paralysis and is helpful to identify the etiology. (authors)

  5. The computed tomography appearance of recurrent and chronic appendicitis.

    Science.gov (United States)

    Rao, P M; Rhea, J T; Novelline, R A; McCabe, C J

    1998-01-01

    The objective of this study was to determine computed tomography (CT) appearance of recurrent and chronic appendicitis. In 100 consecutive appendiceal CT examinations of proven appendicitis, 18 patients met criteria for recurrent (multiple discrete episodes) or chronic (continuous symptoms > 3 weeks, pathological findings) appendicitis. CT findings were reviewed. Ten patients had recurrent appendicitis, 3 had chronic appendicitis, 3 had both, and 2 had pathological chronic appendicitis. CT findings in 18 recurrent/chronic cases were identical to 82 acute appendicitis cases, including pericecal stranding (both 100%), dilated (> 6 mm) appendix (88.9% versus 93.9%), apical thickening (66.7% versus 69.5%), adenopathy (66.7% versus 61.0%), appendolith(s) (50% versus 42.7%), arrowhead (27.8% versus 22.0%), abscess (11.1% versus 11.0%), phlegmon (11.1% versus 6.1%), and fluid (5.6% versus 19.5%). CT findings in recurrent and chronic appendicitis are the same as those in acute appendicitis. Appendiceal CT can be beneficial for evaluating patients with suspected recurrent or chronic appendicitis.

  6. Contraceptive Provision to Adolescent Females Prescribed Teratogenic Medications.

    Science.gov (United States)

    Stancil, Stephani L; Miller, Melissa; Briggs, Holley; Lynch, Daryl; Goggin, Kathy; Kearns, Gregory

    2016-01-01

    Rates of adult women receiving contraceptive provision when simultaneously prescribed a known teratogen are alarmingly low. The prevalence of this behavior among pediatric providers and their adolescent patients is unknown. The objective of this study was to describe pediatric provider behaviors for prescribing teratogens concurrently with counseling, referral, and/or prescribing of contraception (collectively called contraceptive provision) in the adolescent population. A retrospective review was conducted examining visits in 2008-2012 by adolescents aged 14 to 25 years in which a known teratogen (US Food and Drug Administration pregnancy risk category D or X) was prescribed. The electronic medical records were queried for demographic information, evidence of contraceptive provision, and menstrual and sexual histories. The data were analyzed using standard statistical methods. Within 4172 clinic visits, 1694 females received 4506 prescriptions for teratogenic medications. The most commonly prescribed teratogens were topiramate, methotrexate, diazepam, isotretinoin, and enalapril. The subspecialties prescribing teratogens most frequently were neurology, hematology-oncology, and dermatology. Overall, contraceptive provision was documented in 28.6% of the visits. Whites versus nonwhites and older versus younger girls were more likely to receive contraceptive provision. The presence of a federal risk mitigation system for the teratogen also increased the likelihood of contraceptive provision. Our data demonstrate female adolescents prescribed teratogens receive inadequate contraception provision, which could increase their risk for negative pregnancy outcomes. Although the presence of a federal risk mitigation system appears to improve contraceptive provision, these systems are costly and, in some instances, difficult to implement. Efforts to improve provider practices are needed. Copyright © 2016 by the American Academy of Pediatrics.

  7. Changing clinical profile of acute rheumatic fever and rheumatic recurrence

    International Nuclear Information System (INIS)

    Sheikh, A.M.; Sadiq, M.; Rehman, A.U.

    2016-01-01

    Background: Clinical profile of acute rheumatic fever and rheumatic recurrence seems to have changed in countries where rheumatic fever is still endemic. The objectives of this study were to compare clinical profile and outcome of patients suffering initial and recurrent episodes of acute rheumatic fever in children. Methods: This prospective study was conducted in two tertiary care hospitals from January to June 2011. The diagnosis was based on the modified Jones criteria. Sixty children were included in the study, 15 having first episode of rheumatic fever and 45 with rheumatic recurrence. The severity of carditis was assessed by Clinical and echocardiography means. Results: Carditis was the commonest presentation in both first (80 percentage) and recurrent attacks (100 percentage). Arthritis was seen in 60 percentage of children with first episode and in 26.7 percentage with recurrence. The frequency of subcutaneous nodules, invariably associated with carditis, was very high (33.3 percentage in the first and 48.3 percentage in recurrent episodes). Carditis was generally mild during first episode (53.3 percentage) and severe with rheumatic recurrence (55.6 percentage). There was no death in either group. One patient with severe mitral regurgitation and rheumatic recurrence underwent mitral valve repair for intractable heart failure. Conclusion: Clinical profile of rheumatic recurrence and acute rheumatic fever has changed. Rheumatic recurrence is associated with severe carditis. Carditis is more common than arthritis even in the first attack. Sub-cutaneous nodules are a frequent finding invariably associated with carditis. (author)

  8. Risk of Local Recurrence of Benign and Borderline Phyllodes Tumors

    DEFF Research Database (Denmark)

    Borhani-Khomani, Kaveh; Talman, Maj-Lis Møller; Kroman, Niels

    2016-01-01

    women aged 18 years or older, operated from 1999 to 2014, with resected benign or borderline PTs. Information on age, size of primary tumor and recurrence, histological grade, surgical treatment, margin size, and local recurrence were collected from the national Danish Pathology Register. RESULTS.......1-192). We identified 30 local recurrences, i.e., a recurrence rate of 6.3 %. Twenty-three recurrences had similar or lower histological grading than the primary tumor, one primary benign PT recurred as a tumor with unclear diagnosis, and one primary borderline PT recurred as malignant. The number...

  9. Contemporary deep recurrent learning for recognition

    Science.gov (United States)

    Iftekharuddin, K. M.; Alam, M.; Vidyaratne, L.

    2017-05-01

    Large-scale feed-forward neural networks have seen intense application in many computer vision problems. However, these networks can get hefty and computationally intensive with increasing complexity of the task. Our work, for the first time in literature, introduces a Cellular Simultaneous Recurrent Network (CSRN) based hierarchical neural network for object detection. CSRN has shown to be more effective to solving complex tasks such as maze traversal and image processing when compared to generic feed forward networks. While deep neural networks (DNN) have exhibited excellent performance in object detection and recognition, such hierarchical structure has largely been absent in neural networks with recurrency. Further, our work introduces deep hierarchy in SRN for object recognition. The simultaneous recurrency results in an unfolding effect of the SRN through time, potentially enabling the design of an arbitrarily deep network. This paper shows experiments using face, facial expression and character recognition tasks using novel deep recurrent model and compares recognition performance with that of generic deep feed forward model. Finally, we demonstrate the flexibility of incorporating our proposed deep SRN based recognition framework in a humanoid robotic platform called NAO.

  10. Subdural Hematoma Presenting as Recurrent Syncope.

    Science.gov (United States)

    Bruner, David I; Jamros, Christine; Cogar, William

    2015-09-01

    Syncope is a common emergency department (ED) complaint. Recurrent syncope is less common, but may be concerning for serious underlying pathology. It often requires a broad diagnostic evaluation that may include neurologic imaging. We present the case of a 75-year-old man with non-small-cell carcinoma who presented to the ED for recurrent syncope after coughing spells over the 2 weeks preceding his arrival at the ED. He had a normal cardiac evaluation, however, he had some subacute neurologic changes that prompted obtaining a computed tomography (CT) scan of the head. This led to the diagnosis of atraumatic subdural hematoma that was causing transient transtentorial herniation leading to the recurrent syncope. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Emergency physicians should be aware that recurrent syncope is a possible presentation of increased intracranial pressure that may be due to a mass lesion, particularly if the patient has any acute or subacute neurologic changes. Although this association with a subdual hematoma is rare, other cases of mass lesions leading to syncope after coughing spells have been reported in the literature. Published by Elsevier Inc.

  11. Prognosis of Primary and Recurrent Chondrosarcoma of the Rib.

    Science.gov (United States)

    Roos, Eva; van Coevorden, Frits; Verhoef, Cornelis; Wouters, Michel W; Kroon, Herman M; Hogendoorn, Pancras C W; van Houdt, Winan J

    2016-03-01

    Chondrosarcoma of the rib is a rare disease. Although surgery is the only curative treatment option, rib resection with an adequate margin can be challenging and local recurrence is a frequent problem. In this study, the prognosis of primary and recurrent chondrosarcoma of the rib is reported. Retrospective analysis was performed of patients treated for chondrosarcoma of the rib between 1984 and 2014 in three major tertiary referral centers in The Netherlands. Clinical and histopathological features were analyzed for their prognostic value using Kaplan-Meier and Cox proportional hazard analysis. Endpoints were set at local recurrent disease, metastasis rate, or death. Overall, 76 patients underwent a resection for a primary chondrosarcoma, and 26 patients underwent a resection for a recurrent chondrosarcoma. Five-year overall survival in the primary group was 90%, local recurrence rate was 17%, and metastasis rate was 12%. The 5-year outcome after recurrent chondrosarcoma was lower, with an overall survival of 65%, local recurrence rate of 27%, and metastasis rate of 27%. For primary chondrosarcoma, tumor size >5 cm and a positive resection margin were correlated with worse overall survival [hazard ratio (HR) 3.28, 95% confidence interval (CI) 1.03-10.44; HR 2.92, 95% CI 1.03-8.25). A higher histological grade was correlated with a higher local recurrence and metastasis rate (HR 5.92, 95% CI 1.11-31.65; HR 6.96, 95% CI 1.15-42.60). Surgical resection of both primary and recurrent chondrosarcoma of the rib is an effective treatment strategy. The oncological outcome after surgery is worse in tumors >5 cm, in tumors with positive resection margins and grade 3 chondrosarcoma.

  12. Implicit self-esteem in recurrently depressed patients

    NARCIS (Netherlands)

    Risch, A.K.; Bubal, A.; Birk, U.; Morina, N.; Steffens, M.C.; Stangier, U.

    2010-01-01

    Negative self-esteem is suggested to play an important role in the recurrence of depressive episodes. This study investigated whether repeated experiences of a negative view of the self within a recurrent course of depression might cause implicit self-esteem to be impaired and negative

  13. Recurrence Density Enhanced Complex Networks for Nonlinear Time Series Analysis

    Science.gov (United States)

    Costa, Diego G. De B.; Reis, Barbara M. Da F.; Zou, Yong; Quiles, Marcos G.; Macau, Elbert E. N.

    We introduce a new method, which is entitled Recurrence Density Enhanced Complex Network (RDE-CN), to properly analyze nonlinear time series. Our method first transforms a recurrence plot into a figure of a reduced number of points yet preserving the main and fundamental recurrence properties of the original plot. This resulting figure is then reinterpreted as a complex network, which is further characterized by network statistical measures. We illustrate the computational power of RDE-CN approach by time series by both the logistic map and experimental fluid flows, which show that our method distinguishes different dynamics sufficiently well as the traditional recurrence analysis. Therefore, the proposed methodology characterizes the recurrence matrix adequately, while using a reduced set of points from the original recurrence plots.

  14. Anastomotic Recurrence of Sigmoid Colon Cancer over Five Years after Surgery

    Directory of Open Access Journals (Sweden)

    Takahiro Yamauchi

    2013-10-01

    Full Text Available The incidence of anastomotic recurrence after curative resection of colorectal cancer is relatively low compared to that of other types of recurrence, such as hepatic, lung and local recurrence. However, almost all cases of anastomotic recurrence of colorectal cancer occur within 3 years after surgery. We experienced a rare case of anastomotic recurrence in whom colonoscopy revealed no signs of recurrence 3 years after surgery; however, anastomotic recurrence was detected over 5 years after surgery. A 60-year-old female with a history of surgery for cancer of the cecum in her forties underwent sigmoidectomy and right colectomy with D3 lymph node dissection for both stage IIA sigmoid colon cancer and stage IIA transverse colon cancer. Computed tomography and colonoscopy revealed no signs of recurrence 3 years after surgery; however, 5 years and 4 months after surgery, colonoscopy demonstrated surrounding flaring and swelling in the anastomotic area of the sigmoid colon, and a biopsy revealed an adenocarcinoma. Under the diagnosis of anastomotic recurrence over 5 years after surgery, lower anterior resection was performed. The patient has exhibited no other signs of recurrence in the 2 years since the last operation.

  15. Fermi-Pasta-Ulam recurrence and modulation instability

    Science.gov (United States)

    Kuznetsov, E. A.

    2017-01-01

    We give a qualitative conceptual explanation of the Fermi-Pasta-Ulam (FPU) like recurrence in the onedimensional focusing nonlinear Schrodinger equation (NLSE). The recurrence can be considered as a result of the nonlinear development of the modulation instability. All known exact localized solitary wave solutions describing propagation on the background of the modulationally unstable condensate show the recurrence to the condensate state after its interaction with solitons. The condensate state locally recovers its original form with the same amplitude but a different phase after soliton leave its initial region. Based on the integrability of the NLSE, we demonstrate that the FPU recurrence takes place not only for condensate, but also for a more general solution in the form of the cnoidal wave. This solution is periodic in space and can be represented as a solitonic lattice. That lattice reduces to isolated soliton solution in the limit of large distance between solitons. The lattice transforms into the condensate in the opposite limit of dense soliton packing. The cnoidal wave is also modulationally unstable due to soliton overlapping. The recurrence happens at the nonlinear stage of the modulation instability. Due to generic nature of the underlying mathematical model, the proposed concept can be applied across disciplines and nonlinear systems, ranging from optical communications to hydrodynamics.

  16. Learning State Space Dynamics in Recurrent Networks

    Science.gov (United States)

    Simard, Patrice Yvon

    Fully recurrent (asymmetrical) networks can be used to learn temporal trajectories. The network is unfolded in time, and backpropagation is used to train the weights. The presence of recurrent connections creates internal states in the system which vary as a function of time. The resulting dynamics can provide interesting additional computing power but learning is made more difficult by the existence of internal memories. This study first exhibits the properties of recurrent networks in terms of convergence when the internal states of the system are unknown. A new energy functional is provided to change the weights of the units in order to the control the stability of the fixed points of the network's dynamics. The power of the resultant algorithm is illustrated with the simulation of a content addressable memory. Next, the more general case of time trajectories on a recurrent network is studied. An application is proposed in which trajectories are generated to draw letters as a function of an input. In another application of recurrent systems, a neural network certain temporal properties observed in human callosally sectioned brains. Finally the proposed algorithm for stabilizing dynamics around fixed points is extended to one for stabilizing dynamics around time trajectories. Its effects are illustrated on a network which generates Lisajous curves.

  17. Recurrent Partial Words

    Directory of Open Access Journals (Sweden)

    Francine Blanchet-Sadri

    2011-08-01

    Full Text Available Partial words are sequences over a finite alphabet that may contain wildcard symbols, called holes, which match or are compatible with all letters; partial words without holes are said to be full words (or simply words. Given an infinite partial word w, the number of distinct full words over the alphabet that are compatible with factors of w of length n, called subwords of w, refers to a measure of complexity of infinite partial words so-called subword complexity. This measure is of particular interest because we can construct partial words with subword complexities not achievable by full words. In this paper, we consider the notion of recurrence over infinite partial words, that is, we study whether all of the finite subwords of a given infinite partial word appear infinitely often, and we establish connections between subword complexity and recurrence in this more general framework.

  18. Recurrent Bilateral Breast Abscesses after Sternotomy

    Directory of Open Access Journals (Sweden)

    Hamza Cinar

    2012-01-01

    Full Text Available Median sternotomy is the most commonly used incision in cardiothoracic procedures. Development of breast abscess after sternotomy is a very rare situation. We present a case of sternal wound infection with recurrent bilateral breast abscess after sternotomy. Our case is the first and only case in the literature due to the presence of sternal wound infection with recurrent bilateral breast abscess after sternotomy.

  19. 29 CFR 780.305 - 500 man-day provision.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false 500 man-day provision. 780.305 Section 780.305 Labor...) Statutory Provisions § 780.305 500 man-day provision. (a) Section 3(u) of the Act defines man-day to mean “any day during which an employee performs agricultural labor for not less than 1 hour.” 500 man-days...

  20. Content provision and multi-homing

    OpenAIRE

    Pires, Armando J. Garcia

    2015-01-01

    We analyze the effects of multi-homing consumers on content provision by media firms. We develop a model where media firms compete on content provision and advertising revenues, and consumers enjoy network effects from consuming content that other consumers also consume. Media firms have to choose if they are single-content or multi-content, and in the latter case how much content to offer. Competition for advertising revenues gives a two-sided market nature to our model, since advertisers pr...

  1. A Comprehensive Study of Costs Associated With Recurrent Clostridium difficile Infection.

    Science.gov (United States)

    Rodrigues, Rodrigo; Barber, Grant E; Ananthakrishnan, Ashwin N

    2017-02-01

    BACKGROUND Clostridium difficile infection (CDI) is the most common healthcare-associated infection and is associated with considerable morbidity. Recurrent CDI is a key contributing factor to this morbidity. Despite an estimated 83,000 recurrences annually in the United States, there are few accurate estimates of costs associated with recurrent CDI. OBJECTIVE We performed this study (1) to identify the health consequences of recurrent CDI including need for repeat hospitalization, intensive care unit (ICU) stay, and surgery; (2) to determine costs associated with recurrent CDI and identify determinants of such costs; and (3) to compare the outcomes and costs of recurrent CDI to those who develop reinfection. METHODS We identified all patients with confirmed recurrent CDI between January to December 2013 at a single referral center. Healthcare burden associated with recurrence including diagnostic testing, pharmacologic treatment, and inpatient and outpatient healthcare visits were identified in the 12 months following the first recurrence. Total healthcare costs were calculated, and the predictors of high healthcare utilization were identified. RESULTS Our study population included 98 patients with recurrent CDI. The median interval between the initial infection and recurrence was 37 days. The mean age of the cohort was 67 years, two-thirds were women (62%), and the mean Charlson index was 8.6. During the year following the first recurrence of CDI, each patient underwent a mean of 4.4 stool C. difficile toxin tests and received a mean of 2.5 prescriptions for oral vancomycin (range, 0-6). Most patients (84%) with recurrence had a CDI-related hospitalization, and 6% underwent colectomy. The mean total CDI-associated cost was $34,104 per patient, with hospitalization costs accounting for 68%, surgery 20%, and drug treatment 8% of this cost, respectively. Extrapolating to the United States overall, we estimate an annual cost of $2.8 billion related to recurrent CDI

  2. Bank loan loss provisions research: A review

    Directory of Open Access Journals (Sweden)

    Peterson K. Ozili

    2017-09-01

    Full Text Available We review the recent academic and policy literature on bank loan loss provisioning. Among other things, we observe that there exist some interaction between LLPs and existing prudential, accounting, institutional, cultural, religious, tax and fiscal frameworks which differ across countries; and we find that managerial discretion in provisioning is strongly linked to income smoothing, capital management, signalling, tax management and other objectives. We also address several issues including the ethical dimensions of income smoothing, factors influencing income smoothing, methodological issues in LLP modelling and the dynamic loan loss provisioning experiment; which opens up several avenues for further research such as: finding a balance between sufficient LLPs which regulators want versus transparent LLPs which standard setters want; the sensitivity of abnormal LLPs to changes in equity; the persistence of abnormal LLPs following CEO exit; country-specific interventions that induce LLP procyclicality in emerging countries; the impact of Basel III on banks' provisioning discretion; LLP behaviour among systemic and non-systemic financial institutions; etc. We conclude that regulators need to pay attention to how much discretion lending institutions should have in determining reported provision estimates, and this has been a long standing issue.

  3. The risk factors for recurrence of chronic subdural hematoma.

    Science.gov (United States)

    Ohba, Shigeo; Kinoshita, Yu; Nakagawa, Toru; Murakami, Hideki

    2013-01-01

    Chronic subdural hematoma (CSDH) is a common disease in the elderly, and the recurrence rate of CSDH is reported to range from 2.3 to 33%. We performed a retrospective review of a number of CSDH cases and the potential factors associated with CSDH recurrence. The patient population comprised 112 men and 65 women with a mean age of 74.7 years. We analyzed the following factors: age, sex, antiplatelet and anticoagulant use, hematoma laterality, hematoma thickness, degree of midline shift and internal architecture of the hematoma in the preoperative CT films, use of irrigation, direction of the drainage tube, width of the subdural space, and degree of midline shift and the presence of a massive subdural air collection in the postoperative CT films. Univariate analysis revealed that there was a trend for different rates of recurrence among the different types of hematomas. The presence of a postoperative massive subdural air collection tended to be associated with the recurrence of hematoma. Multivariate analysis revealed that separated hematomas were significantly associated with CSDH recurrence, whereas the presence of postoperative massive subdural air collection tended to be associated with hematoma recurrence. Neither univariate nor multivariate analysis could demonstrate an association between the direction of the drainage tube and the recurrence of CSDH.

  4. Imaging of prostate cancer local recurrences: why and how?

    International Nuclear Information System (INIS)

    Rouviere, Olivier; Lyonnet, Denis; Vitry, Thierry

    2010-01-01

    Because prostate cancer local recurrences can be efficiently treated by salvage therapies, it becomes critical to detect them early. The first alert is the rise of the prostate specific antigen (PSA) level after the post-treatment nadir, which can correspond to a distant recurrence, a local recurrence or both. This so-called biochemical failure (BF) is defined as PSA level >0.2 ng/ml after radical prostatectomy (RP) and PSA level > nadir+2 ng/ml after radiotherapy. There is no consensual definition of BF after cryotherapy, high-intensity focused ultrasound (HIFU) ablation or brachytherapy. Local recurrences after RP are treated by radiotherapy, those after radiotherapy by RP, cryotherapy, brachytherapy or HIFU ablation. Recurrences after cryotherapy or HIFU ablation can be treated by a second session or radiotherapy. Recurrences after brachytherapy are difficult to treat. In patients with BF, MRI can detect local recurrences, whatever the initial treatment was. Dynamic contrast-enhanced MRI seems particularly accurate. The role of spectroscopy remains controversial. Ultrasound-based techniques are less accurate, but this may change with the advent of ultrasonic contrast media. These recent advances in imaging may improve the outcome of salvage therapies (by improving patient selection and treatment targeting) and should open the way to focal salvage treatments in the near future. (orig.)

  5. Imaging of prostate cancer local recurrences: why and how?

    Energy Technology Data Exchange (ETDEWEB)

    Rouviere, Olivier; Lyonnet, Denis [Universite de Lyon, Lyon (France); Universite Lyon 1, Faculte de Medecine Lyon Nord (France); Service d' Imagerie Urinaire et Vasculaire, Hospices Civils de Lyon, Hopital Edouard Herriot, Lyon (France); INSERM U 556, Lyon (France); Vitry, Thierry [Service d' Imagerie Urinaire et Vasculaire, Hospices Civils de Lyon, Hopital Edouard Herriot, Lyon (France)

    2010-05-15

    Because prostate cancer local recurrences can be efficiently treated by salvage therapies, it becomes critical to detect them early. The first alert is the rise of the prostate specific antigen (PSA) level after the post-treatment nadir, which can correspond to a distant recurrence, a local recurrence or both. This so-called biochemical failure (BF) is defined as PSA level >0.2 ng/ml after radical prostatectomy (RP) and PSA level > nadir+2 ng/ml after radiotherapy. There is no consensual definition of BF after cryotherapy, high-intensity focused ultrasound (HIFU) ablation or brachytherapy. Local recurrences after RP are treated by radiotherapy, those after radiotherapy by RP, cryotherapy, brachytherapy or HIFU ablation. Recurrences after cryotherapy or HIFU ablation can be treated by a second session or radiotherapy. Recurrences after brachytherapy are difficult to treat. In patients with BF, MRI can detect local recurrences, whatever the initial treatment was. Dynamic contrast-enhanced MRI seems particularly accurate. The role of spectroscopy remains controversial. Ultrasound-based techniques are less accurate, but this may change with the advent of ultrasonic contrast media. These recent advances in imaging may improve the outcome of salvage therapies (by improving patient selection and treatment targeting) and should open the way to focal salvage treatments in the near future. (orig.)

  6. Bank Loan Loss Provisions, Investor Protection and the Macroeconomy

    OpenAIRE

    Ozili, Peterson K

    2017-01-01

    This study investigates the non-discretionary determinants of bank loan loss provisions in Africa after controlling for macroeconomic fluctuation, financial development and investor protection. We find that non-performing loans, loan-to-asset ratio and loan growth are significant non-discretionary drivers of bank provisions in the African region. We observe that bank provision is a positive function of non-performing loans up to a threshold beyond which bank provisions will no longer increase...

  7. Treatment Outcomes and Prognostic Factors After Recurrence of Esophageal Squamous Cell carcinoma.

    Science.gov (United States)

    Hamai, Yoichi; Hihara, Jun; Emi, Manabu; Furukawa, Takaoki; Ibuki, Yuta; Yamakita, Ichiko; Kurokawa, Tomoaki; Okada, Morihito

    2017-12-29

    The evaluation of treatment outcomes and detection of prognostic factors after recurrence are very important for tailoring optimal therapies for individual patients with recurrent esophageal cancer. We reviewed 133 patients in whom esophageal squamous cell carcinoma (ESCC) recurred after curative surgery, and assessed recurrence patterns, treatment outcomes and prognostic factors. Recurrence in 57 (42.9%), 54 (40.6%) and 22 (16.5%) patients was locoregional, distant and combined, respectively. The median amounts of elapsed time until recurrence and median survival after recurrence for all patients were 9.1 and 8.3 months, respectively. Univariate and multivariate analyses selected time to recurrence (hazard ratio [HR], 0.98; 95% confidence interval [CI], 0.97-0.999; p = 0.04), recurrence location (locoregional vs. distant: HR, 1.63; 95% CI, 1.03-2.61; p = 0.04), number of organs with recurrence (1 vs. 3: HR, 3.49; 95% CI, 1.23-9.87; p = 0.02) and treatment after recurrence (best supportive care, [BSC] vs. chemotherapy [CT] or radiation therapy [RT]: HR, 0.37; 95% CI, 0.15-0.94; p = 0.04; BSC vs. CT and RT: HR, 0.50; 95% CI, 0.26-0.94; p = 0.03; BSC vs. HR, 0.47; 95% CI, 0.25-0.88; p = 0.02) as independent factors for survival after recurrence. Seventeen (12.8%) patients who had localized lymph node recurrence and lung oligometastasis and received multidisciplinary therapy after recurrence survived for >3 years thereafter. Despite the poor survival of patients with ESCC and early or distant recurrence or recurrence in ≥3 recurrent organs, appropriate multimodal therapies should be tailored for individual patients with recurrent ESCC.

  8. Factors predicting recurrence in successfully treated cases of anisometropic amblyopia

    Directory of Open Access Journals (Sweden)

    Rohit Saxena

    2013-01-01

    Full Text Available Context: Recurrence after successful treatment of amblyopia is known and understanding the risk factors could help effective management. Aim: To measure incidence of recurrence in successfully treated cases of anisometropic amblyopia and evaluate factors predicting it. Settings and Design: Cohort Study at a tertiary level institution. Materials and Methods: Successfully treated anisometropic amblyopes aged 4−12 years were followed up for 1 year after stopping therapy. Best corrected visual acuity (BCVA, refractive error, stereoacuity and contrast sensitivity were evaluated at baseline and follow-up. Statistical Analysis: Intergroup analysis with appropriate tests: Chi-square test, Fisher′s exact test, Wilcoxon rank sum test and paired t-test. Results: One hundred and two patients with mean age at diagnosis 7.06 μ 1.81 years were followed-up for a mean duration of 1.0 μ 0.2 years. The mean pre-treatment BCVA (LogMAR score at diagnosis was 0.73 μ 0.36 units which improved to 0.20 μ 0.00 with treatment and after 1 year of stopping treatment was 0.22 μ 0.07. Thirteen (12.74% patients showed amblyopia recurrence during follow-up. Risk of recurrence was higher with older age of onset of treatment (6.64 μ 1.77 years without recurrence v/s 8.53 μ 1.39 years with recurrence, P = 0.0014. Greater extent of improvement of VA (P = 0.048 and final VA at stopping occlusion (P = 0.03 were associated with higher recurrence. Binocularity status or stereoacuity changes were not associated with risk of recurrence. Conclusions: Significant numbers of children suffer recurrence of amblyopia after stopping therapy. Older age, better BCVA after stopping therapy and greater magnitude of improvement in BCVA are important risk factors for recurrence. Careful follow-up is essential for early detection and management of recurrence.

  9. Factors predicting recurrence in successfully treated cases of anisometropic amblyopia

    Science.gov (United States)

    Saxena, Rohit; Puranik, Shraddha; Singh, Digvijay; Menon, Vimla; Sharma, Pradeep; Phuljhele, Swati

    2013-01-01

    Context: Recurrence after successful treatment of amblyopia is known and understanding the risk factors could help effective management. Aim: To measure incidence of recurrence in successfully treated cases of anisometropic amblyopia and evaluate factors predicting it. Settings and Design: Cohort Study at a tertiary level institution. Materials and Methods: Successfully treated anisometropic amblyopes aged 4−12 years were followed up for 1 year after stopping therapy. Best corrected visual acuity (BCVA), refractive error, stereoacuity and contrast sensitivity were evaluated at baseline and follow-up. Statistical Analysis: Intergroup analysis with appropriate tests: Chi-square test, Fisher's exact test, Wilcoxon rank sum test and paired t-test. Results: One hundred and two patients with mean age at diagnosis 7.06 ± 1.81 years were followed-up for a mean duration of 1.0 ± 0.2 years. The mean pre-treatment BCVA (LogMAR score) at diagnosis was 0.73 ± 0.36 units which improved to 0.20 ± 0.00 with treatment and after 1 year of stopping treatment was 0.22 ± 0.07. Thirteen (12.74%) patients showed amblyopia recurrence during follow-up. Risk of recurrence was higher with older age of onset of treatment (6.64 ± 1.77 years without recurrence v/s 8.53 ± 1.39 years with recurrence, P = 0.0014). Greater extent of improvement of VA (P = 0.048) and final VA at stopping occlusion (P = 0.03) were associated with higher recurrence. Binocularity status or stereoacuity changes were not associated with risk of recurrence. Conclusions: Significant numbers of children suffer recurrence of amblyopia after stopping therapy. Older age, better BCVA after stopping therapy and greater magnitude of improvement in BCVA are important risk factors for recurrence. Careful follow-up is essential for early detection and management of recurrence. PMID:24343594

  10. Factors predicting recurrence in successfully treated cases of anisometropic amblyopia.

    Science.gov (United States)

    Saxena, Rohit; Puranik, Shraddha; Singh, Digvijay; Menon, Vimla; Sharma, Pradeep; Phuljhele, Swati

    2013-11-01

    Recurrence after successful treatment of amblyopia is known and understanding the risk factors could help effective management. To measure incidence of recurrence in successfully treated cases of anisometropic amblyopia and evaluate factors predicting it. Cohort Study at a tertiary level institution. Successfully treated anisometropic amblyopes aged 4-12 years were followed up for 1 year after stopping therapy. Best corrected visual acuity (BCVA), refractive error, stereoacuity and contrast sensitivity were evaluated at baseline and follow-up. Intergroup analysis with appropriate tests: Chi-square test, Fisher's exact test, Wilcoxon rank sum test and paired t-test. One hundred and two patients with mean age at diagnosis 7.06 μ 1.81 years were followed-up for a mean duration of 1.0 μ 0.2 years. The mean pre-treatment BCVA (LogMAR score) at diagnosis was 0.73 μ 0.36 units which improved to 0.20 μ 0.00 with treatment and after 1 year of stopping treatment was 0.22 μ 0.07. Thirteen (12.74%) patients showed amblyopia recurrence during follow-up. Risk of recurrence was higher with older age of onset of treatment (6.64 μ 1.77 years without recurrence v/s 8.53 μ 1.39 years with recurrence, P = 0.0014). Greater extent of improvement of VA (P = 0.048) and final VA at stopping occlusion (P = 0.03) were associated with higher recurrence. Binocularity status or stereoacuity changes were not associated with risk of recurrence. Significant numbers of children suffer recurrence of amblyopia after stopping therapy. Older age, better BCVA after stopping therapy and greater magnitude of improvement in BCVA are important risk factors for recurrence. Careful follow-up is essential for early detection and management of recurrence.

  11. Recurrent diabetic ketoacidosis

    DEFF Research Database (Denmark)

    Skinner, T. Chas

    2002-01-01

    Longitudinal studies indicate that 20% of paediatric patients account for 80% of all admissions for diabetic ketoacidosis (DKA). The frequency of DKA peaks during adolescence and, although individuals generally go into remission, they may continue to have bouts of recurrent DKA in adulthood. The ...

  12. GRECOS Project (Genotyping Recurrence Risk of Stroke): The Use of Genetics to Predict the Vascular Recurrence After Stroke.

    Science.gov (United States)

    Fernández-Cadenas, Israel; Mendióroz, Maite; Giralt, Dolors; Nafria, Cristina; Garcia, Elena; Carrera, Caty; Gallego-Fabrega, Cristina; Domingues-Montanari, Sophie; Delgado, Pilar; Ribó, Marc; Castellanos, Mar; Martínez, Sergi; Freijo, Marimar; Jiménez-Conde, Jordi; Rubiera, Marta; Alvarez-Sabín, José; Molina, Carlos A; Font, Maria Angels; Grau Olivares, Marta; Palomeras, Ernest; Perez de la Ossa, Natalia; Martinez-Zabaleta, Maite; Masjuan, Jaime; Moniche, Francisco; Canovas, David; Piñana, Carlos; Purroy, Francisco; Cocho, Dolores; Navas, Inma; Tejero, Carlos; Aymerich, Nuria; Cullell, Natalia; Muiño, Elena; Serena, Joaquín; Rubio, Francisco; Davalos, Antoni; Roquer, Jaume; Arenillas, Juan Francisco; Martí-Fábregas, Joan; Keene, Keith; Chen, Wei-Min; Worrall, Bradford; Sale, Michele; Arboix, Adrià; Krupinski, Jerzy; Montaner, Joan

    2017-05-01

    Vascular recurrence occurs in 11% of patients during the first year after ischemic stroke (IS) or transient ischemic attack. Clinical scores do not predict the whole vascular recurrence risk; therefore, we aimed to find genetic variants associated with recurrence that might improve the clinical predictive models in IS. We analyzed 256 polymorphisms from 115 candidate genes in 3 patient cohorts comprising 4482 IS or transient ischemic attack patients. The discovery cohort was prospectively recruited and included 1494 patients, 6.2% of them developed a new IS during the first year of follow-up. Replication analysis was performed in 2988 patients using SNPlex or HumanOmni1-Quad technology. We generated a predictive model using Cox regression (GRECOS score [Genotyping Reurrence Risk of Stroke]) and generated risk groups using a classification tree method. The analyses revealed that rs1800801 in the MGP gene (hazard ratio, 1.33; P =9×10 - 03 ), a gene related to artery calcification, was associated with new IS during the first year of follow-up. This polymorphism was replicated in a Spanish cohort (n=1.305); however, it was not significantly associated in a North American cohort (n=1.683). The GRECOS score predicted new IS ( P =3.2×10 - 09 ) and could classify patients, from low risk of stroke recurrence (1.9%) to high risk (12.6%). Moreover, the addition of genetic risk factors to the GRECOS score improves the prediction compared with previous Stroke Prognosis Instrument-II score ( P =0.03). The use of genetics could be useful to estimate vascular recurrence risk after IS. Genetic variability in the MGP gene was associated with vascular recurrence in the Spanish population. © 2017 American Heart Association, Inc.

  13. Assessing the risk of recurrent venous thromboembolism--a practical approach.

    Science.gov (United States)

    Fahrni, Jennifer; Husmann, Marc; Gretener, Silvia B; Keo, Hong H

    2015-01-01

    Recurrent venous thromboembolism (VTE) is associated with increased morbidity and mortality. This risk is lowered by anticoagulation, with a large effect in the initial phase following the venous thromboembolic event, and with a smaller effect in terms of secondary prevention of recurrence when extended anticoagulation is performed. On the other hand, extended anticoagulation is associated with an increased risk of major bleeding and thus leads to morbidity and mortality. Therefore, it is necessary to assess the risk of recurrence for VTE on an individual basis, and a recommendation for secondary prophylaxis should be specifically based on risk calculation of recurrence of VTE and bleeding. In this review, we provide a comprehensive summary of relevant risk factors for recurrent VTE and a practical approach for assessing the risk of recurrence in daily practice.

  14. Connection between recurrence time statistics and anomalous transport

    International Nuclear Information System (INIS)

    Zaslavsky, G.M.; Tippett, M.K.

    1991-01-01

    For a model stationary flow with hexagonal symmetry, the recurrence time statistics are studied. The model has been shown to have a sharp transition from normal to anomalous transport. Here it is shown that this transition is accompanied by a correspondent change of the recurrence time statistics from normal to anomalous. The latter one displays the existence of a power tail. Recurrence time statistics provide a local measurement of anomalous transport that is of practical interest

  15. FDG PET/CT appearance of local osteosarcoma recurrences in pediatric patients

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, Susan E.; Gelfand, Michael J. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Shulkin, Barry L.; McCarville, M.B. [St. Jude Children' s Research Hospital, Department of Diagnostic Imaging, Memphis, TN (United States)

    2017-12-15

    Osteosarcoma is the most common pediatric malignant bone tumor, frequently surgically managed with limb salvage rather than amputation. Local recurrences are seen in up to 9% of osteosarcoma patients, with CT and MRI imaging often limited by metal artifacts. To describe the [F-18]2-fluoro-2-deoxyglucose (FDG) PET/CT appearance of local osteosarcoma recurrences with correlation to findings on other imaging modalities. A retrospective review of pediatric osteosarcoma patients imaged with FDG PET/CT was performed in patients with pathologically proven local recurrences. FDG PET/CT findings were reviewed and correlated with available comparison imaging studies. Ten local osteosarcoma recurrences in eight pediatric osteosarcoma patients were imaged with FDG PET/CT. All eight patients had a local recurrence after limb salvage; two patients had a second local recurrence after amputation. All local recurrences were seen with FDG PET/CT, demonstrating solid (n=5) or peripheral/nodular (n=5) FDG uptake patterns. Maximum standard uptake values (SUVs) ranged from 3.0 to 15.7. In five recurrences imaged with FDG PET/CT and MRI, MRI was limited or nondiagnostic in three. In four recurrences imaged with FDG PET/CT and bone scan, the bone scan was negative in three. Local osteosarcoma recurrences are well visualized by FDG PET/CT, demonstrating either solid or peripheral/nodular FDG uptake with a wide range of maximum SUVs. FDG PET/CT demonstrates the full extent of local recurrences, while MRI can be limited by artifact from metallic hardware. PET/CT appears to be more sensitive than bone scan in detecting local osteosarcoma recurrences. (orig.)

  16. Strategic Managment to Support Quality of Service

    OpenAIRE

    Berset, Geir

    2004-01-01

    Distributed computing adds to the complexity of ensuring Quality of Service (QoS) to applications. Middleware architectures are trying to solve the complexity of distributed computing, but has generally not been addressing the topic of providing platform managed QoS. It is a common understanding that one should try to provide QoS based on a general solution for capturing QoS requirements and managing resources. This thesis proposes a scheme increasing the probability of delivering QoS to s...

  17. Association of recurrent pregnancy loss with chromosomal ...

    African Journals Online (AJOL)

    EB

    for recurrent pregnancy loss and these patients are the best candidates for offering prenatal genetic diagnosis by the help of which there is a possibility of obtaining a better reproductive outcome. Key words: chromosomal abnormality, recurrent pregnancy loss, thrombophilia. African Health Sciences 2013; 13(2): 447 - 452 ...

  18. Recurrent midgut volvulus following a Ladd procedure

    International Nuclear Information System (INIS)

    Panghaal, Vikash; Levin, Terry L.; Han, Bokyung

    2008-01-01

    We present a case of recurrent midgut volvulus in a 3-year-old girl with a history of midgut volvulus repair as an infant. Awareness of the possibility of recurrence even several years following an initial Ladd procedure is crucial to ensure prompt treatment in these children. (orig.)

  19. Recurrent midgut volvulus following a Ladd procedure

    Energy Technology Data Exchange (ETDEWEB)

    Panghaal, Vikash; Levin, Terry L.; Han, Bokyung [Montefiore Medical Center, Department of Radiology, Bronx, NY (United States)

    2008-04-15

    We present a case of recurrent midgut volvulus in a 3-year-old girl with a history of midgut volvulus repair as an infant. Awareness of the possibility of recurrence even several years following an initial Ladd procedure is crucial to ensure prompt treatment in these children. (orig.)

  20. Recurrent medulloblastoma: Frequency of tumor enhancement on Gd-DTPA MR imaging

    International Nuclear Information System (INIS)

    Rollins, N.; Mendelsohn, D.; Mulne, A.; Barton, R.; Diehl, J.; Reyes, N.; Sklar, F.

    1990-01-01

    Thirty-two children with medulloblastoma were evaluated postoperatively with conventional and gadolinium-enhanced MR imaging. Eleven patients had abnormal cranial MR studies; nine of these had recurrent tumor. In six patients recurrent tumor enhanced with Gd, while in the other three patients recurrent tumor did not enhance. The remaining two patients had areas of abnormal Gd enhancement that were caused by radiation-induced breakdown of the blood-brain barrier rather than by recurrent tumor. This study shows that not all recurrent medulloblastoma enhances and that the absence of Gd enhancement does not necessarily indicate the absence of recurrent tumor

  1. Treatment of breast cancer recurrence with fast electrons

    Energy Technology Data Exchange (ETDEWEB)

    Gremilov, V A; Svistunova, T M; Migmanova, N Sh [Akademiya Meditsinskikh Nauk SSSR, Leningrad. Inst. Onkologii

    1978-01-01

    Feasibility of treating mammary gland cancer recurrences by means of fast electron is investigated. Local recurrences and metastases were inradiated with 10 MeV fast electrons, and regional ones - with 15 MeV fast electrons. The irradiation technique used permitted the occurence of early and late local radiation responses as well as complications to be avoided. The treatment effect resulted from a value, form and clinical course of recurrence, as well as from cumulative dose with optimum value of 5000-6000 rad. The direct and nearest treatment results in respect of local criterion of the effect are recognized as satisfactory. Taking into consideration, that local and regional recurrences and metastases in the most part of patients are the beginning of clinical manifestation of tumor process generalization, it is assumed, that local treatment of local and regional recurrences and metastases of mammary gland cancer is not reliable therapeutic measure and must be combined with general treatment (chemo- and hormonotherapy) and specific measures enhancing the total resistance of the body.

  2. Recurrent frequency-size distribution of characteristic events

    Directory of Open Access Journals (Sweden)

    S. G. Abaimov

    2009-04-01

    Full Text Available Statistical frequency-size (frequency-magnitude properties of earthquake occurrence play an important role in seismic hazard assessments. The behavior of earthquakes is represented by two different statistics: interoccurrent behavior in a region and recurrent behavior at a given point on a fault (or at a given fault. The interoccurrent frequency-size behavior has been investigated by many authors and generally obeys the power-law Gutenberg-Richter distribution to a good approximation. It is expected that the recurrent frequency-size behavior should obey different statistics. However, this problem has received little attention because historic earthquake sequences do not contain enough events to reconstruct the necessary statistics. To overcome this lack of data, this paper investigates the recurrent frequency-size behavior for several problems. First, the sequences of creep events on a creeping section of the San Andreas fault are investigated. The applicability of the Brownian passage-time, lognormal, and Weibull distributions to the recurrent frequency-size statistics of slip events is tested and the Weibull distribution is found to be the best-fit distribution. To verify this result the behaviors of numerical slider-block and sand-pile models are investigated and the Weibull distribution is confirmed as the applicable distribution for these models as well. Exponents β of the best-fit Weibull distributions for the observed creep event sequences and for the slider-block model are found to have similar values ranging from 1.6 to 2.2 with the corresponding aperiodicities CV of the applied distribution ranging from 0.47 to 0.64. We also note similarities between recurrent time-interval statistics and recurrent frequency-size statistics.

  3. Prevention of Recurrent Staphylococcal Skin Infections

    OpenAIRE

    Creech, C. Buddy; Al-Zubeidi, Duha N.; Fritz, Stephanie A.

    2015-01-01

    Staphylococcus aureus infections pose a significant health burden. The emergence of community-associated methicillin-resistant S. aureus has resulted in an epidemic of skin and soft tissue infections (SSTI), and many patients experience recurrent SSTI. As S. aureus colonization is associated with subsequent infection, decolonization is recommended for patients with recurrent SSTI or in settings of ongoing transmission. S. aureus infections often cluster within households and asymptomatic carr...

  4. 7 CFR 457.142 - Northern potato crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Northern potato crop insurance provisions. 457.142... INSURANCE CORPORATION, DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.142 Northern potato crop insurance provisions. The Northern Potato Crop Insurance Provisions for the 2008 and succeeding...

  5. MRI in recurrent nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Ng, S.H.; Ko, S.F.; Wan, Y.L.; Chang, J.T.C.; Chen, W.C.; Tang, L.M.

    1999-01-01

    In this study, we retrospectively reviewed the MRI features of recurrent nasopharyngeal carcinoma (NPC) in 72 patients who underwent MRI before and after gadolinium injection. Recurrent NPC exhibited a high degree of regional spread and a variety of signal intensities and contours. MRI showed a nasopharyngeal mass in 50 patients (69.4 %); other sites of involvement included the parapharyngeal space (44.4 %), nasal cavity (12.5 %), paranasal sinuses (27.8 %), oropharynx (4.2 %), orbit (8.3 %), infratemporal fossa (18.1 %), skull base (59.8 %), intracranial area (51.4 %) and regional lymph nodes (15.3 %). On T2-weighted images, the nasopharyngeal mass gave high signal in 9 of 50 cases (18 %), intermediate in 27 (54 %), mixed in 8 (16 %) and low signal in 6 (12 %). Contrast enhancement was strong in 12 cases (24 %), moderate in 29 (58 %) and heterogeneous in 9 (18 %). The lesion was convex in 31 cases (62 %) and concave or straight in 19 (38 %). Recognition of the distribution and the appearance of recurrent NPC on MRI is essential for timely diagnosis and appropriate treatment. (orig.)

  6. [Recurrent benign cystic peritoneal mesothelioma].

    Science.gov (United States)

    Stroescu, C; Negulescu, Raluca; Herlea, V; David, L; Ivanov, B; Nitipir, Cornelia; Popescu, I

    2008-01-01

    The benign cystic peritoneal mesothelioma (BCPM) is a rare neoplasm affecting mainly females at reproductive age. The natural history and physiopathology of the BCPM are not entirely known. It is mainly characterized by the lack of malignant elements, no tendency to metastasis and by a pervasive tendency to generate local recurrences after surgical removal. The clinical manifestations are insidious, uncharacteristic; the benign cystic peritoneal mesothelioma is often discovered during a surgical procedure addressing another condition. Imaging tests can raise the suspicion of BCPM but the diagnostic can only be confirmed by histopathological examination corroborated with an immunohistochemical analysis. There are no long term studies dictating a single therapeutic attitude but a high risk of local recurrences and the possibility of transformation into malignant mesothelioma have lead to the current tendency towards an aggressive treatment of the tumor. We present the case of a recurrent benign cystic peritoneal mesothelioma in a 40 years old female patient, emphasizing the therapeutic approach and the role of radical surgery in the treatment of BPCM.

  7. Recurrences in well-differentiated cancer of Thyroid

    International Nuclear Information System (INIS)

    Cadena Enrique

    2000-01-01

    The paper analyzes epidemic data on the relapses as well as of the advantages of the complementary handling of the well differentiated carcinoma of thyroid, the diagnostic methods are commented and the treatment of the same ones, the article includes topics like epidemiology, prevention, recurrences detection, recurrences handling and clinical case

  8. Convolutional neural networks for prostate cancer recurrence prediction

    Science.gov (United States)

    Kumar, Neeraj; Verma, Ruchika; Arora, Ashish; Kumar, Abhay; Gupta, Sanchit; Sethi, Amit; Gann, Peter H.

    2017-03-01

    Accurate prediction of the treatment outcome is important for cancer treatment planning. We present an approach to predict prostate cancer (PCa) recurrence after radical prostatectomy using tissue images. We used a cohort whose case vs. control (recurrent vs. non-recurrent) status had been determined using post-treatment follow up. Further, to aid the development of novel biomarkers of PCa recurrence, cases and controls were paired based on matching of other predictive clinical variables such as Gleason grade, stage, age, and race. For this cohort, tissue resection microarray with up to four cores per patient was available. The proposed approach is based on deep learning, and its novelty lies in the use of two separate convolutional neural networks (CNNs) - one to detect individual nuclei even in the crowded areas, and the other to classify them. To detect nuclear centers in an image, the first CNN predicts distance transform of the underlying (but unknown) multi-nuclear map from the input HE image. The second CNN classifies the patches centered at nuclear centers into those belonging to cases or controls. Voting across patches extracted from image(s) of a patient yields the probability of recurrence for the patient. The proposed approach gave 0.81 AUC for a sample of 30 recurrent cases and 30 non-recurrent controls, after being trained on an independent set of 80 case-controls pairs. If validated further, such an approach might help in choosing between a combination of treatment options such as active surveillance, radical prostatectomy, radiation, and hormone therapy. It can also generalize to the prediction of treatment outcomes in other cancers.

  9. Causes of recurrent pneumonia in children in a general hospital.

    Science.gov (United States)

    Hoving, M F Paulien; Brand, Paul L P

    2013-03-01

    Because the few previous studies on underlying causes of recurrent pneumonia in children have come from tertiary care referral centres where selection bias may be important, the aim of this study was to examine underlying causes of recurrent pneumonia in children in a general hospital. We performed a retrospective chart review in a general hospital of 62 children with recurrent pneumonia over a 7.5 years period. In 19 patients (30.6%), no cause was identified, commonly because favourable natural history obviated the need for a full and invasive diagnostic work-up. Other underlying causes included recurrent aspiration in 16 patients (25.7%), lung disease (airway stenosis, bronchiectasis, middle lobe syndrome or tracheooesophageal fistula) in 10 patients (16.1%) and immune deficiency in 10 patients (16.1%). In contrast to previous studies, asthma was never diagnosed as an underlying cause, but diagnostic confusion between asthma (or recurrent upper respiratory tract infections) and recurrent pneumonia was common. The cause of recurrent pneumonia in children remains elusive in almost a third of patients, partly because the favourable natural history consistent with immune system maturation eliminates the need for further diagnostic procedures. Asthma is more likely a differential diagnostic consideration than an underlying cause of recurrent pneumonia in children. A standardised diagnostic guideline is needed to improve knowledge on causes of recurrent pneumonia in children. © 2013 The Authors. Journal of Paediatrics and Child Health © 2013 Paediatrics and Child Health Division (Royal Australasian College of Physicians).

  10. Recurrence of vocal fold leukoplakia after carbon dioxide laser therapy.

    Science.gov (United States)

    Chen, Min; Chen, Jian; Cheng, Lei; Wu, Haitao

    2017-09-01

    This work aims to analyze the recurrence of vocal fold leukoplakia after carbon dioxide (CO 2 ) laser resection. In this retrospective study, all patients undergoing CO 2 laser resection of vocal fold leukoplakia were followed up for at least 2 years. Recurrence was diagnosed as any presence of leukoplakia in the vocal cord subsequent to previous successful complete resection. A total of 326 patients with complete resection of vocal fold leukoplakia and follow-up subsequent surveillance laryngoscopy were studied. The recurrence rate, the recurrence time, and risk factors were evaluated. Of these, 52 (16.0%) patients experienced recurrence with a mean follow-up time of 50.5 ± 15.4 months. The mean time to recurrence was 16.2 ± 14.1 months. Univariate analysis showed that the size of lesion (P vocal fold leukoplakia, long-term follow-up is required after CO 2 laser resection. In conclusion, the size of lesion combined with the pathological grade are important risk factors that predict vocal fold leukoplakia recurrence.

  11. A study on strategic provisioning of cloud computing services.

    Science.gov (United States)

    Whaiduzzaman, Md; Haque, Mohammad Nazmul; Rejaul Karim Chowdhury, Md; Gani, Abdullah

    2014-01-01

    Cloud computing is currently emerging as an ever-changing, growing paradigm that models "everything-as-a-service." Virtualised physical resources, infrastructure, and applications are supplied by service provisioning in the cloud. The evolution in the adoption of cloud computing is driven by clear and distinct promising features for both cloud users and cloud providers. However, the increasing number of cloud providers and the variety of service offerings have made it difficult for the customers to choose the best services. By employing successful service provisioning, the essential services required by customers, such as agility and availability, pricing, security and trust, and user metrics can be guaranteed by service provisioning. Hence, continuous service provisioning that satisfies the user requirements is a mandatory feature for the cloud user and vitally important in cloud computing service offerings. Therefore, we aim to review the state-of-the-art service provisioning objectives, essential services, topologies, user requirements, necessary metrics, and pricing mechanisms. We synthesize and summarize different provision techniques, approaches, and models through a comprehensive literature review. A thematic taxonomy of cloud service provisioning is presented after the systematic review. Finally, future research directions and open research issues are identified.

  12. A Study on Strategic Provisioning of Cloud Computing Services

    Directory of Open Access Journals (Sweden)

    Md Whaiduzzaman

    2014-01-01

    Full Text Available Cloud computing is currently emerging as an ever-changing, growing paradigm that models “everything-as-a-service.” Virtualised physical resources, infrastructure, and applications are supplied by service provisioning in the cloud. The evolution in the adoption of cloud computing is driven by clear and distinct promising features for both cloud users and cloud providers. However, the increasing number of cloud providers and the variety of service offerings have made it difficult for the customers to choose the best services. By employing successful service provisioning, the essential services required by customers, such as agility and availability, pricing, security and trust, and user metrics can be guaranteed by service provisioning. Hence, continuous service provisioning that satisfies the user requirements is a mandatory feature for the cloud user and vitally important in cloud computing service offerings. Therefore, we aim to review the state-of-the-art service provisioning objectives, essential services, topologies, user requirements, necessary metrics, and pricing mechanisms. We synthesize and summarize different provision techniques, approaches, and models through a comprehensive literature review. A thematic taxonomy of cloud service provisioning is presented after the systematic review. Finally, future research directions and open research issues are identified.

  13. Risk factors for recurrent vulvovaginal candidiasis

    Directory of Open Access Journals (Sweden)

    Janković Slobodan

    2010-01-01

    Full Text Available Background/Aim. Recurrent vulvovaginal candidiasis is relatively frequent condition, and may have serious health consequences, like chronic vulvovaginal pain syndrome. The aim of our study was to determine possible risk factors for recurrent vulvovaginal candidiasis in non-pregnant females within the reproductive age. Methods. The design of our study was of a case-control type. Case and control patients were selected from the gynecological patients at six primary care facilities in Serbia and in Montenegro. The data on the patients' health condition, concomitant therapy and diseases were taken from their records, and the data on habits were obtained by unstructured interview. For potential risk factors crude odds ratios were calculated, and then adjusted by logistic regression. Results. A total of fifty-one patients had four or more episodes of vulvovaginal candidiasis during the last year (cases, and 132 patients with one to three episodes of vulvovaginal candidiasis were sampled as controls, matched by age. The only two significant associations were found between recurrent vulvovaginal candidiasis and continual wearing of panty liners during the last year (Odds ratio - ORadjusted: 3.97; confidence interval - CI: 1.57-10.02; p = 0.004, and between recurrent vulvovaginal candidiasis and predominant use of vaginal tampons during menstruation in the last year (ORadjusted: 4.25; CI: 1.11-16.27; p = 0.035. The synergistic effect was observed for the concurrent continual wearing of panty liners during the last year and selfmedication with antimycotics. Conclusions. Local factors, like wearing of panty liners or use of tampons during menstruation, may promote recurrence of vulvovaginal candidiasis, especially in patients who practice selfmedication with antimycotics.

  14. Recurrent Acute Tonsillitis, The 'Core' Issue

    Directory of Open Access Journals (Sweden)

    Saikat Samaddar

    2016-04-01

    Full Text Available Introduction: Today bacteriological and patho-anatomical considerations too are taken into account while treating a case of tonsillitis. Past decade has seen the rise of resistance amongst the common pathogens, as well as rise in the number of unusual offenders. Determination of the true offending organism and prescribing an antibiotic as per the sensitivity pattern is of utmost importance.  Materials and Method: A prospective longitudinal study was conducted in a tertiary care hospital in Kolkata. The study population consisted of patients presenting with recurrent attacks of acute tonsillitis. Determination of throat swab micro flora, ASO titre and core tissue microflora was done and correlated statistically. Result: There was poor correlation between throat swab and core tissue microflora. Positive predictive value of throat swab was 10%. Pseudomonas is the predominant flora harbouring tonsillar core in our study population. Amoxicillin the most commonly prescribed antibiotic stands out to be the most resistant one. No statistical significance could be reached comparing streptococcal tonsillitis with ASO titre. Discussion: The real pathology within the tonsil core is not always reflected in routine throat swab and bacteriology of recurrent tonsillitis may differ in different regions. ASO titre estimation adds up to the economic burden if rheumatic fever is not suspected. Judicious use of antibiotics based on true sensitivity pattern is encouraged. In the era of antibiotics Tonsillectomy still holds an important position in the management of recurrent attacks. Conclusion: Pseudomonas was found to be the most common pathogen in recurrent acute tonsillitis. Core tissue study remains the Gold standard in identifying the pathogenic organism. Oral third generation Cephalosporin was the most efficacious antibiotic for recurrent tonsillitis in our study population.

  15. Optimization of recurrent neural networks for time series modeling

    DEFF Research Database (Denmark)

    Pedersen, Morten With

    1997-01-01

    The present thesis is about optimization of recurrent neural networks applied to time series modeling. In particular is considered fully recurrent networks working from only a single external input, one layer of nonlinear hidden units and a li near output unit applied to prediction of discrete time...... series. The overall objective s are to improve training by application of second-order methods and to improve generalization ability by architecture optimization accomplished by pruning. The major topics covered in the thesis are: 1. The problem of training recurrent networks is analyzed from a numerical...... of solution obtained as well as computation time required. 3. A theoretical definition of the generalization error for recurrent networks is provided. This definition justifies a commonly adopted approach for estimating generalization ability. 4. The viability of pruning recurrent networks by the Optimal...

  16. Recurrent postoperative sciatica: Evaluation with MR imaging and enhanced CT

    International Nuclear Information System (INIS)

    Duoauferrier, R.; Frocrain, L.; Husson, J.L.

    1987-01-01

    The authors prospectively compared surface coil MR (SCMR) imaging and CT with iodinate contrast enhancement in 50 patients with recurrent postoperative sciatica. Of the 50 patients enrolled in the study, surgical treatment was elected in 27 patients after independent examination of SCMR imaging and enhanced CT. All predictions made with the 27 SCMR images were surgically confirmed. The surgical findings were 20 recurrent disk herniations, five recurrent disk herniations with scar tissue, one disk herniation above the level of diskectomy, and one disk herniation below the level of diskectomy. The surgical findings of the 12 patients who had scar tissue on CT were seven recurrent disk herniations, four recurrent disk herniations with scar tissue, and one disk herniation below the operated level. SCMR imaging was more sensitive and more specific than CT to differentiate scar tissue from recurrent disk herniation

  17. Clinical analysis of patients with hepatocellular carcinoma recurrence after living-donor liver transplantation.

    Science.gov (United States)

    Na, Gun Hyung; Hong, Tae Ho; You, Young Kyoung; Kim, Dong Goo

    2016-07-07

    To evaluated patterns and outcomes of hepatocellular carcinoma (HCC) recurrence after living donor liver transplantation (LDLT). From 2001 to 2014, 293 patients underwent LDLT for HCC at our transplant center. We retrospectively reviewed 54 (18.4%) patients with HCC recurrence after LDLT. We evaluated patterns and outcomes of HCC recurrence after LDLT, with particular attention to the Milan criteria at transplantation, treatments for HCC-recurrent patients, and factors related to survival after HCC recurrence. Furthermore, we evaluated the efficacy of combination treatment of sorafenib and an mTOR inhibitor. The 1-, 2-, and 3-year overall survival rates after HCC recurrence were 41.1%, 20.5%, and 15.4%, respectively. The median time interval between LDLT and HCC recurrence was 6.5 mo. Although recurrence rates according to the Milan criteria at LDLT were significantly different, HCC recurrence patterns and survival rates after HCC recurrence were not significantly different between the two groups. Time to recurrence < 12 mo (P = 0.048), multiple recurrences at HCC recurrence (P = 0.038), and palliative treatment for recurrent tumors (P = 0.003) were significant independent prognostic factors for poor survival after HCC recurrence in a multivariate analysis. The combination treatment of sorafenib and sirolimus showed survival benefits in the palliative treatment group (P = 0.005). Curative treatment for recurrent HCC after LDLT is the most important factor in survival rates after HCC recurrence and combination treatments of sorafenib and an mTOR inhibitor could have survival benefits in patients with HCC recurrence after LT in the palliative treatment group.

  18. Rectal bacteriotherapy for recurrent Clostridium difficile-associated diarrhoea

    DEFF Research Database (Denmark)

    Tvede, M; Tinggaard, M; Helms, M

    2015-01-01

    Clostridium difficile infection is one of the most common nosocomial infections. Among other alternatives to standard treatment with vancomycin for recurrent infection are faecal microbiota transplantation and rectal bacteriotherapy with a fixed mixture of intestinal bacterial strains isolated from...... for relapsing C. difficile in Denmark, 2000-2012. The primary end point was recurrent diarrhoea within 30 days after treatment. A total of 55 patients were included in this case series. Thirty-five patients (64%) had no recurrence within 30 days of bacteriotherapy. Patients with recurrence tended to be older....... difficile episode less than 6 months before bacteriotherapy. The most common adverse events were abdominal pain (10.9%) and worsening diarrhoea (4.3%). One patient was hospitalized 10 days after treatment with appendicitis, fever, and Escherichia coli bacteremia. The results from this study indicate...

  19. Recurrent spontaneous attacks of dizziness.

    Science.gov (United States)

    Lempert, Thomas

    2012-10-01

    This article describes the common causes of recurrent vertigo and dizziness that can be diagnosed largely on the basis of history. Ninety percent of spontaneous recurrent vertigo and dizziness can be explained by six disorders: (1) Ménière disease is characterized by vertigo attacks, lasting 20 minutes to several hours, with concomitant hearing loss, tinnitus, and aural fullness. Aural symptoms become permanent during the course of the disease. (2) Attacks of vestibular migraine may last anywhere from minutes to days. Most patients have a previous history of migraine headaches, and many experience migraine symptoms during the attack. (3) Vertebrobasilar TIAs affect older adults with vascular risk factors. Most attacks last less than 1 hour and are accompanied by other symptoms from the posterior circulation territory. (4) Vestibular paroxysmia is caused by vascular compression of the eighth cranial nerve. It manifests itself with brief attacks of vertigo that recur many times per day, sometimes with concomitant cochlear symptoms. (5) Orthostatic hypotension causes brief episodes of dizziness lasting seconds to a few minutes after standing up and is relieved by sitting or lying down. In older adults, it may be accompanied by supine hypertension. (6) Panic attacks usually last minutes, occur in specific situations, and are accompanied by choking, palpitations, tremor, heat, and anxiety. Less common causes of spontaneous recurrent vertigo and dizziness include perilymph fistula, superior canal dehiscence, autoimmune inner ear disease, otosclerosis, cardiac arrhythmia, and medication side effects. Neurologists need to venture into otolaryngology, internal medicine, and psychiatry to master the differential diagnosis of recurrent dizziness.

  20. 48 CFR 828.106-72 - Contract provision.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Contract provision. 828... GENERAL CONTRACTING REQUIREMENTS BONDS AND INSURANCE Bonds and Other Financial Protections 828.106-72 Contract provision. Insert 852.228-72, Assisting Service-Disabled Veteran-Owned and Veteran-Owned Small...

  1. Recurrence in Major Depression: A Conceptual Analysis

    Science.gov (United States)

    Monroe, Scott M.; Harkness, Kate L.

    2011-01-01

    Theory and research on major depression have increasingly assumed a recurrent and chronic disease model. Yet not all people who become depressed suffer recurrences, suggesting that depression is also an acute, time-limited condition. However, few if any risk indicators are available to forecast which of the initially depressed will or will not…

  2. Dynamic provisioning for community services

    CERN Document Server

    Qi, Li

    2013-01-01

    Dynamic Provisioning for Community Services outlines a dynamic provisioning and maintenance mechanism in a running distributed system, e.g. the grid, which can be used to maximize the utilization of computing resources and user demands. The book includes a complete and reliable maintenance system solution for the large-scale distributed system and an interoperation mechanism for the grid middleware deployed in the United States, Europe, and China. The experiments and evaluations have all been practically implemented for ChinaGrid, and the best practices established can help readers to construc

  3. Optimal Provision of Public Goods

    DEFF Research Database (Denmark)

    Kreiner, Claus Thustrup; Verdelin, Nicolaj

    2009-01-01

    There currently exist two competing approaches in the literature on the optimal provision of public goods. The standard approach highlights the importance of distortionary taxation and distributional concerns. The new approach neutralizes distributional concerns by adjusting the non-linear income...... for the optimal level of a public good without imposing strong assumptions on preferences. This formula shows that distortionary taxation may have a role to play as in the standard approach. However, the main determinants of optimal provision are completely different and the traditional formula with its emphasis...

  4. Recurrent cerebral thrombosis

    International Nuclear Information System (INIS)

    Iwamoto, Toshihiko; Abe, Shin-e; Kubo, Hideki; Hanyu, Haruo; Takasaki, Masaru

    1992-01-01

    Neuroradiological techniques were used to elucidate pathophysiology of recurrent cerebral thrombosis. Twenty-two patients with cerebral thrombosis who suffered a second attack under stable conditions more than 22 days after the initial stroke were studied. Hypertension, diabetes mellitus, and hypercholesterolemia were also seen in 20, 8, and 12 patients, respectively. The patients were divided into three groups according to their symptoms: (I) symptoms differed between the first and second strokes (n=12); (II) initial symptoms were suddenly deteriorated (n=6); and (III) symptoms occurring in groups I and II were seen (n=4). In group I, contralateral hemiparesis or suprabulbar palsy was often associated with the initial hemiparesis. The time of recurrent stroke varied from 4 months to 9 years. CT and MRI showed not only lacunae in both hemispheres, but also deep white-matter ischemia of the centrum semi-ovale. In group II, hemiparesis or visual field defect was deteriorated early after the initial stroke. In addition, neuroimaging revealed that infarction in the posterior cerebral artery was progressed on the contralateral side, or that white matter lesion in the middle artery was enlarged in spite of small lesion in the left cerebral hemisphere. All patients in group III had deterioration of right hemiparesis associated with aphasia. CT, MRI, SPECT, and angiography indicated deep white-matter ischemia caused by main trunk lesions in the left hemisphere. Group III seemed to be equivalent to group II, except for laterality of the lesion. Neuroradiological assessment of the initial stroke may help to predict the mode of recurrence, although pathophysiology of cerebral thrombosis is complicated and varies from patient to patient. (N.K.)

  5. Primary spontaneous pneumothorax in menstruating females has high recurrence

    Science.gov (United States)

    Mehta, Christopher K.; Stanifer, Bryan P.; Fore-Kosterski, Susan; Gillespie, Colin; Yeldandi, Anjana; Meyerson, Shari; Odell, David D.; DeCamp, Malcolm M.; Bharat, Ankit

    2016-01-01

    Background Primary spontaneous pneumothorax (PSP) is treated based on studies that have predominantly consisted of tall male subjects. Here we determined recurrence of PSP in average-statured menstruating women and studied prevalence of catamenial pneumothorax (CP) in this population. Methods Males and menstruating females, aged 18-55 years, without underlying lung disease or substance abuse were retrospectively studied between 2009-2015. A chest pathologist reviewed all specimens for thoracic endometriosis. Kaplan-Meier curves were constructed to determine recurrence. Results The median age of females (n=33) and males (n=183) was 33.4 and 31.6 years, respectively. In females, nine (27%) had left-sided and 24 (73%) had right-sided PSP, treated with tube thoracostomy. Recurrence occurred in 21 (64%) females with median follow up of 14 months and was treated with thoracoscopic pleurodesis. Right PSP had higher recurrence (70%) compared to left (56%, p=0.02). Four females (12%) presented with recurrent tension pneumothorax within six months. Eight (24%) patients had PSP within 72 hours of menses, meeting clinical criteria of CP. All these were placed on hormonal suppression after initial episode but went on to develop recurrence that was treated with pleurodesis. However, classic endometrial glands were not found in any biopsy specimens obtained during the thoracoscopy. In contrast to female subjects, only 8 (4.4%) average-statured males had recurrence (p<0.001) with a median follow up of 16 months. Conclusions PSP in healthy average-statured menstruating women has high recurrence compared to male counterparts. CP is a clinical diagnosis and often recurs despite hormonal suppression therapy. PMID:27345097

  6. 31 CFR 586.406 - Provision of services.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Provision of services. 586.406 Section 586.406 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE... & MONTENEGRO) KOSOVO SANCTIONS REGULATIONS Interpretations § 586.406 Provision of services. (a) Except as...

  7. 48 CFR 970.1170-2 - Contract provision.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Contract provision. 970... SUPPLEMENTARY REGULATIONS DOE MANAGEMENT AND OPERATING CONTRACTS Describing Agency Needs 970.1170-2 Contract provision. The Contracting Officer shall insert the clause at 970.5211-1, Work authorization, in each...

  8. Palbociclib Isethionate in Treating Younger Patients With Recurrent, Progressive, or Refractory Central Nervous System Tumors

    Science.gov (United States)

    2017-09-27

    Childhood Choroid Plexus Tumor; Childhood Ependymoblastoma; Childhood Grade III Meningioma; Childhood High-grade Cerebellar Astrocytoma; Childhood High-grade Cerebral Astrocytoma; Childhood Medulloepithelioma; Recurrent Childhood Anaplastic Astrocytoma; Recurrent Childhood Anaplastic Oligoastrocytoma; Recurrent Childhood Anaplastic Oligodendroglioma; Recurrent Childhood Brain Stem Glioma; Recurrent Childhood Cerebellar Astrocytoma; Recurrent Childhood Cerebral Astrocytoma; Recurrent Childhood Giant Cell Glioblastoma; Recurrent Childhood Glioblastoma; Recurrent Childhood Gliomatosis Cerebri; Recurrent Childhood Gliosarcoma; Recurrent Childhood Medulloblastoma; Recurrent Childhood Pineoblastoma; Recurrent Childhood Supratentorial Primitive Neuroectodermal Tumor

  9. On the integral values of a curious recurrence

    OpenAIRE

    Dvornicich, Roberto; Veneziano, Francesco; Zannier, Umberto

    2014-01-01

    We discuss a problem initially thought for the Mathematical Olympiad but which has several interpretations. The recurrence sequences involved in this problem may be generalized to recurrence sequences related to a much larger set of diophantine equations.

  10. 50 CFR 660.320 - Open access fishery-crossover provisions.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Open access fishery-crossover provisions... West Coast Groundfish-Open Access Fisheries § 660.320 Open access fishery—crossover provisions. (a) Operating in both limited entry and open access fisheries. See provisions at § 660.60, subpart C. (b...

  11. Multiscale recurrence analysis of spatio-temporal data

    Science.gov (United States)

    Riedl, M.; Marwan, N.; Kurths, J.

    2015-12-01

    The description and analysis of spatio-temporal dynamics is a crucial task in many scientific disciplines. In this work, we propose a method which uses the mapogram as a similarity measure between spatially distributed data instances at different time points. The resulting similarity values of the pairwise comparison are used to construct a recurrence plot in order to benefit from established tools of recurrence quantification analysis and recurrence network analysis. In contrast to other recurrence tools for this purpose, the mapogram approach allows the specific focus on different spatial scales that can be used in a multi-scale analysis of spatio-temporal dynamics. We illustrate this approach by application on mixed dynamics, such as traveling parallel wave fronts with additive noise, as well as more complicate examples, pseudo-random numbers and coupled map lattices with a semi-logistic mapping rule. Especially the complicate examples show the usefulness of the multi-scale consideration in order to take spatial pattern of different scales and with different rhythms into account. So, this mapogram approach promises new insights in problems of climatology, ecology, or medicine.

  12. Recurrent Silent Thyroiditis as a Sequela of Postpartum Thyroiditis

    Science.gov (United States)

    Kim, Paul

    2014-01-01

    Thyroiditis encompasses a group of disorders characterized by thyroid inflammation. Though clinically indistinguishable from silent thyroiditis, postpartum thyroiditis occurs in women within 12 months after delivery. Recurrent postpartum thyroiditis in subsequent pregnancies is common, but recurrent silent thyroiditis is rare. We reported a case of patient with recurrent episodes of thyroiditis, unrelated to pregnancy, after an episode of postpartum thyroiditis. It is of interest that postpartum thyroiditis and silent thyroiditis could occur closely to each other; however, the link between these disorders is not well established. This report is to remind physicians of the possibility of recurrent silent thyroiditis in women with a history of postpartum thyroiditis. PMID:24987536

  13. Real-time services in IP network architectures

    Science.gov (United States)

    Gilardi, Antonella

    1996-12-01

    The worldwide internet system seems to be the success key for the provision of real time multimedia services to both residential and business users and someone says that in such a way broadband networks will have a reason to exist. This new class of applications that use multiple media (voice, video and data) impose constraints to the global network nowadays consisting of subnets with various data links. The attention will be focused on the interconnection of IP non ATM and ATM networks. IETF and ATM forum are currently involved in the developing specifications suited to adapt the connectionless IP protocol to the connection oriented ATM protocol. First of all the link between the ATM and the IP service model has to be set in order to match the QoS and traffic requirements defined in the relative environment. A further significant topic is represented by the mapping of IP resource reservation model onto the ATM signalling and in the end it is necessary to define how the routing works when there are QoS parameters associated. This paper, considering only unicast applications, will examine the above issues taking as a starting point the situation where an host launches as call set up request with the relevant QoS and traffic descriptor and at some point a router at the edge of the ATM network has to decide how forwarding and request in order to establish an end to end link with the right capabilities. The aim is to compare the proposals emerging from different standard bodies to point out convergency or incompatibility.

  14. Contemporary Management of Recurrent Nodal Disease in Differentiated Thyroid Carcinoma

    Science.gov (United States)

    Na’ara, Shorook; Amit, Moran; Fridman, Eran; Gil, Ziv

    2016-01-01

    Differentiated thyroid carcinoma (DTC) comprises over 90% of thyroid tumors and includes papillary and follicular carcinomas. Patients with DTC have an excellent prognosis, with a 10-year survival rate of over 90%. However, the risk of recurrent tumor ranges between 5% and 30% within 10 years of the initial diagnosis. Cervical lymph node disease accounts for the majority of recurrences and in most cases is detected during follow-up by ultrasound or elevated levels of serum thyroglobulin. Recurrent disease is accompanied by increased morbidity. The mainstay of treatment of nodal recurrence is surgical management. We provide an overview of the literature addressing surgical management of recurrent or persistent lymph node disease in patients with DTC. PMID:26886954

  15. Cross over of recurrence networks to random graphs and random ...

    Indian Academy of Sciences (India)

    Recurrence networks are complex networks constructed from the time series of chaotic dynamical systems where the connection between two nodes is limited by the recurrence threshold. This condition makes the topology of every recurrence network unique with the degree distribution determined by the probability ...

  16. Anal incontinence in women with recurrent obstetric anal sphincter rupture

    DEFF Research Database (Denmark)

    Bøgeskov, Reneé; Nickelsen, Carsten Nahne Amtoft; Secher, Niels Jørgen

    2015-01-01

    UNLABELLED: Abstract Objectives: To determine the risk of recurrent anal sphincter rupture (ASR), and compare the risk of anal incontinence (AI) after recurrent ASR, with that seen in women with previous ASR who deliver by caesarean section or vaginally without sustaining a recurrent ASR. METHODS...

  17. Pattern of local recurrence after conservative surgery and whole-breast irradiation

    International Nuclear Information System (INIS)

    Freedman, Gary M.; Anderson, Penny R.; Hanlon, Alexandra L.; Eisenberg, Debra F.; Nicolaou, Nicos

    2005-01-01

    Purpose: Most recurrences in the breast after conservative surgery and whole-breast irradiation have been reported to occur within the same quadrant as the initial primary tumor. We analyzed the long-term risk of recurrence by area of the breast after whole-breast irradiation. Materials and Methods: In all, 1,990 women with Stage 0-II breast cancer were treated with conservative surgery and whole-breast irradiation from 1970-1998. Stage was ductal carcinoma in situ in 237, T1 in 1273, and T2 in 480 patients. Of 120 local recurrences, 71 were classified as true local (confined to the original quadrant) and 49 as elsewhere (involving outside the original quadrant). Kaplan-Meier methodology was used to calculate 5-year, 10-year, and 15-year rates of recurrence (95% confidence intervals in parentheses). The median follow-up is 80 months. Results: There was no apparent difference in the 15-year rate of true local vs. elsewhere recurrence, but the time to recurrence was different. The rate of true local recurrence was 2%, 5%, and 7% (5-9%) at 5, 10, and 15 years, respectively. The recurrences elsewhere in the breast were rare at 5 (1%) and 10 (2%) years, but increased to 6 (3-9%) at 15 years. This 15-year rate of elsewhere recurrence was half the rate of contralateral breast cancers of 13% (10-16%). Conclusions: Recurrence elsewhere in the breast is rare for the first 10 years, but by 15 years is nearly equal to true local recurrence even after whole-breast irradiation. The 15-year rate of elsewhere recurrence was half the rate of contralateral breast cancers. This may indicate a therapeutic effect of whole-breast radiation for other areas of the breast. Very long follow-up will be needed for partial breast irradiation with or without tamoxifen to show that the risk of elsewhere recurrence is not significantly different than after whole-breast irradiation

  18. Recurrent Silent Thyroiditis as a Sequela of Postpartum Thyroiditis

    OpenAIRE

    Hanseree, Preaw; Salvador, Vincent Bryan; Sachmechi, Issac; Kim, Paul

    2014-01-01

    Thyroiditis encompasses a group of disorders characterized by thyroid inflammation. Though clinically indistinguishable from silent thyroiditis, postpartum thyroiditis occurs in women within 12 months after delivery. Recurrent postpartum thyroiditis in subsequent pregnancies is common, but recurrent silent thyroiditis is rare. We reported a case of patient with recurrent episodes of thyroiditis, unrelated to pregnancy, after an episode of postpartum thyroiditis. It is of interest that postpar...

  19. Stress Reduction in Improving Quality of Life in Patients With Recurrent Gynecologic or Breast Cancer

    Science.gov (United States)

    2015-10-08

    Anxiety Disorder; Depression; Fatigue; Leydig Cell Tumor; Ovarian Sarcoma; Ovarian Stromal Cancer; Pain; Peritoneal Carcinomatosis; Pseudomyxoma Peritonei; Recurrent Breast Cancer; Recurrent Cervical Cancer; Recurrent Endometrial Carcinoma; Recurrent Fallopian Tube Cancer; Recurrent Gestational Trophoblastic Tumor; Recurrent Ovarian Epithelial Cancer; Recurrent Ovarian Germ Cell Tumor; Recurrent Primary Peritoneal Cavity Cancer; Recurrent Uterine Sarcoma; Recurrent Vaginal Cancer; Recurrent Vulvar Cancer

  20. Detecting negative selection on recurrent mutations using gene genealogy

    Science.gov (United States)

    2013-01-01

    Background Whether or not a mutant allele in a population is under selection is an important issue in population genetics, and various neutrality tests have been invented so far to detect selection. However, detection of negative selection has been notoriously difficult, partly because negatively selected alleles are usually rare in the population and have little impact on either population dynamics or the shape of the gene genealogy. Recently, through studies of genetic disorders and genome-wide analyses, many structural variations were shown to occur recurrently in the population. Such “recurrent mutations” might be revealed as deleterious by exploiting the signal of negative selection in the gene genealogy enhanced by their recurrence. Results Motivated by the above idea, we devised two new test statistics. One is the total number of mutants at a recurrently mutating locus among sampled sequences, which is tested conditionally on the number of forward mutations mapped on the sequence genealogy. The other is the size of the most common class of identical-by-descent mutants in the sample, again tested conditionally on the number of forward mutations mapped on the sequence genealogy. To examine the performance of these two tests, we simulated recurrently mutated loci each flanked by sites with neutral single nucleotide polymorphisms (SNPs), with no recombination. Using neutral recurrent mutations as null models, we attempted to detect deleterious recurrent mutations. Our analyses demonstrated high powers of our new tests under constant population size, as well as their moderate power to detect selection in expanding populations. We also devised a new maximum parsimony algorithm that, given the states of the sampled sequences at a recurrently mutating locus and an incompletely resolved genealogy, enumerates mutation histories with a minimum number of mutations while partially resolving genealogical relationships when necessary. Conclusions With their

  1. Novel Insights of Oligometastases and Oligo-Recurrence and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Yuzuru Niibe

    2012-01-01

    Full Text Available Oligometastases and oligo-recurrence are among the most important notions of metastatic and recurrent cancer. The concept of oligometastases is related to the notion that cancer patients with 1–5 metastatic or recurrent lesions that could be treated by local therapy achieve long-term survival or cure, while the concept of oligo-recurrence is related to the notion that cancer patients with 1–5 metastatic or recurrent lesions that could be treated by local therapy have controlled primary lesions. Achievement of long-term survival or cure in patients with oligometastases and oligo-recurrence is cancer and organ specific. These facts rely on the seed and soil theory and multiple steps of cancer progression. Oligo-recurrence is considered to have a better prognosis than oligometastases. In patients with oligometastases and oligo-recurrence, the oligometastases and oligo-recurrence are sometimes cured with only local therapy, which is an example of the abscopal effect, previously described in relation to cure of lesions outside of the field of radiation therapy without systemic therapy. Oligometastases and oligo-recurrence can now be cured by less invasive local treatment methods combined with systemic therapy. The mechanisms of oligometastases and oligo-recurrence, as well as novel insights into these important concepts, are presented in this paper.

  2. 40 CFR 63.1434 - Equipment leak provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Equipment leak provisions. 63.1434... Standards for Hazardous Air Pollutant Emissions for Polyether Polyols Production § 63.1434 Equipment leak provisions. (a) The owner or operator of each affected source shall comply with the HON equipment leak...

  3. Different duration of Colchicine for preventing recurrence of Gouty arthritis

    Directory of Open Access Journals (Sweden)

    H Karimzadeh

    2006-05-01

    Full Text Available Background: Gout is a Common recurrent clinical syndrome characterized by increased serum uric acid and recurrent attacks of acute arthritis. Colchicine is used for Prophylaxis against recurrence of arthritis, but the duration of its administration has mentioned variable. In this study, optimal duration of prophylactic colchicine for prevention of gouty arthritis was assessed. Methods : In a clinical trial 190 patients with gouty arthritis divided randomly to group 1,2and 3 and received colchicine for 3 to 6, 7 to 9 and 10 to 12 months then colchicine discontinued and the patients followed one year for recurrence of arthritis. Result assessed by survival analysis with Kaplan –Meier method. Results: The probability of recurrence of arthritis (in order of duration of colchicine prophylaxis was 54%, 27.5% and 23%, respectively. The difference between group one and others was statistically significant, but between group 2 and 3 was not statistically significant. Conclusion: The most suitable duration of colchicine prophylaxis that accompanied with lower recurrence rate was 7-9 months, which seems more cost -effective than 10-12 months regimen. Key words: Gout, Colchicine, Arthritis, Recurrence

  4. Laparoscopic Surgery for Recurrent Crohn's Disease

    Directory of Open Access Journals (Sweden)

    Antonino Spinelli

    2012-01-01

    Full Text Available In spite of the recent improvements in drug therapy, surgery still represents the most frequent treatment for Crohn's disease (CD complications. Laparoscopy has been widely applied over the last twenty years in colorectal surgery and was associated with lower postoperative pain, shorter hospitalization, faster return to daily activities, and better cosmetic results. Laparoscopy experienced a slower diffusion in inflammatory bowel disease surgery than in oncologic colorectal surgery, but proved to be safe and effective, and is currently considered the gold standard for the treatment of primary uncomplicated ileocolic CD. Indications for laparoscopy in CD have recently been widened to embrace more complicated or recurrent CD. This paper reviews the available data on the subset of recurrent CD patients. The reported results indicate that laparoscopy may be safely applied even in selected recurrent CD cases in hands of IBD surgeons with broad laparoscopic experience.

  5. Growth of breast cancer recurrences assessed by consecutive MRI

    International Nuclear Information System (INIS)

    Millet, Ingrid; Bouic-Pages, Emmanuelle; Hoa, Denis; Azria, David; Taourel, Patrice

    2011-01-01

    Women with a personal history of breast cancer have a high risk of developing an ipsi- or contralateral recurrence. We aimed to compare the growth rate of primary breast cancer and recurrences in women who had undergone prior breast magnetic resonance imaging (MRI). Three hundred and sixty-two women were diagnosed with breast cancer and had undergone breast MRI at the time of diagnosis in our institution (2005 - 2009). Among them, 37 had at least one prior breast MRI with the lesion being visible but not diagnosed as cancer. A linear regression of tumour volume measured on MRI scans and time data was performed using a generalized logistic model to calculate growth rates. The primary objective was to compare the tumour growth rate of patients with either primary breast cancer (no history of breast cancer) or ipsi- or contralateral recurrences of breast cancer. Twenty women had no history of breast cancer and 17 patients were diagnosed as recurrences (7 and 10 were ipsi- and contralateral, respectively). The tumour growth rate was higher in contralateral recurrences than in ipsilateral recurrences (growth rate [10 -3 days -1 ] 3.56 vs 1.38, p < .001) or primary cancer (3.56 vs 2.09, p = 0.01). Differences in tumour growth were not significant for other patient-, tumour- or treatment-related characteristics. These findings suggest that contralateral breast cancer presents accelerated growth compared to ipsilateral recurrences or primary breast events

  6. Spatial Aspects of the Provision of Forest Ecosystem Services

    DEFF Research Database (Denmark)

    Nielsen, Anne Sofie Elberg

    to the incorporation of spatial factors into cost and benefit evaluation of FES provision. Focus is on assessing where forest ecosystem provision should be undertaken, determinants of private stakeholder provision efforts and welfare consequences of changes in the provision level. Provision of carbon sequestration...... estimates for the U.S. counties of the cost of carbon sequestration from afforestation (conversion of non-forest land to forest), when afforestation is restricted by Holdridge zone climatic conditions. Aside from assessing the overall marginal cost schedule, the spatial distribution of these are examined......, to assess where afforestation should be undertaken for given carbon prices. The second paper investigates the determinants of landowner participation in a Danish voluntary conservation program. Combining contract data of landowners’ actual choices, GIS information on area specific characteristics...

  7. Recurrent giant juvenile fibroadenoma

    Directory of Open Access Journals (Sweden)

    Kathryn S. King

    2017-11-01

    Full Text Available Breast masses in children, though rare, present a difficult clinical challenge as they can represent a wide variety of entities from benign fibroadenomas to phyllodes tumors. Rapidly growing or recurrent masses can be particularly concerning to patients, families and physicians alike. Clinical examination and conventional imaging modalities are not efficacious in distinguishing between different tumor types and surgical excision is often recommended for both final diagnosis and for treatment of large or rapidly growing masses. While surgical excision can result in significant long-term deformity of the breast there are some surgical techniques that can be used to limit deformity and/or aid in future reconstruction. Here we present a case of recurrent giant juvenile fibroadenoma with a review of the clinical presentation, diagnostic tools and treatment options.

  8. [Therapy and course of recurrent odontogenic keratocyst. A case report].

    Science.gov (United States)

    Schultz, Christoph B; Pajarola, Gion F; Grätz, Klaus W

    2005-01-01

    Recurrence following the surgical treatment of keratocysts of the jaws may present a major problem to the oral surgeon. The surgical treatment of patients with odontogenic keratocysts is concerning the high recurrence rate demanding and difficult. It has been suggested that recurrence is a consequence of technical of microcysts in the mucosa overlying the recurrent lesions. Attemps have been made to reduce this high recurrence rate by improved surgical techniques, such as removal of superadjacent mucosa, smoothing of the osseous wall of the cystic cavity, resection of neighboring parts of the mandible, tanning of the epithelial lining of the cyst with Carnoy's solution and marsupialisation. On the basis of a case report it was the aim of the authors to present the surgical treatment of odontogenic, recurrent keratocysts at the Clinic for Maxillo-Facial Surgery, University Hospital Zurich, from the primary operation following the Brosch-procedure in 1971 up to the latest cystectomy in 2004.

  9. Shelter provision and state sovereignty in Calais

    Directory of Open Access Journals (Sweden)

    Michael Boyle

    2017-06-01

    Full Text Available Government provision of shelter for Calais’ migrant population over the last twenty years has prioritised the assertion of state authority over the alleviation of human suffering. Policies in 2015-16, which involved the destruction of informal shelter and the provision of basic alternative accommodation, continued this trend.

  10. 29 CFR 552.108 - Child labor provisions.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Child labor provisions. 552.108 Section 552.108 Labor... OF THE FAIR LABOR STANDARDS ACT TO DOMESTIC SERVICE Interpretations § 552.108 Child labor provisions. Congress made no change in section 12 as regards domestic service employees. Accordingly, the child labor...

  11. 40 CFR 63.1410 - Equipment leak provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Equipment leak provisions. 63.1410... leak provisions. The owner or operator of each affected source shall comply with the requirements of 40 CFR part 63, subpart UU (national emission standards for equipment leaks (control level 2)) for all...

  12. Angiopoietin-2 polymorphism in women with idiopathic recurrent miscarriage.

    Science.gov (United States)

    Pietrowski, Detlef; Tempfer, Clemens; Bettendorf, Hertha; Bürkle, Bernd; Nagele, Fritz; Unfried, Gertrud; Keck, Christoph

    2003-10-01

    To investigate the relationship between idiopathic recurrent miscarriage and a polymorphism of the gene encoding for angiopoietin-2 (ANGPT2), an autochthonous modulator of angiogenesis during pregnancy. Prospective case control study. Academic research institution. One hundred thirty-one women with a history of three or more consecutive pregnancy losses before 20 weeks' gestation, and 125 healthy, postmenopausal controls with at least two live births and no history of pregnancy loss. Peripheral venous puncture. Polymerase chain reaction and restriction fragment length polymorphism analysis were performed to identify the different ANGPT2 alleles. No association between mutant (mt) allele and the occurrence of idiopathic recurrent miscarriage was found. Between women with primary and secondary idiopathic recurrent miscarriage, no statistically significant differences with respect to allele frequencies were observed. This is the first report on the ANGPT2 gene polymorphism in women with idiopathic recurrent miscarriage, demonstrating that the investigated polymorphism is not associated with idiopathic recurrent miscarriage in a white population.

  13. QoS and energy management in cognitive radio network case study approach

    CERN Document Server

    Mishra, Vishram; Lau, Chiew-Tong

    2017-01-01

    This book covers the important aspects involved in making cognitive radio devices portable, mobile and green, while also extending their service life. At the same time, it presents a variety of established theories and practices concerning cognitive radio from academia and industry. Cognitive radio can be utilized as a backbone communication medium for wireless devices. To effectively achieve its commercial application, various aspects of quality of service and energy management need to be addressed. The topics covered in the book include energy management and quality of service provisioning at Layer 2 of the protocol stack from the perspectives of medium access control, spectrum selection, and self-coexistence for cognitive radio networks.

  14. Primary Spontaneous Pneumothorax in Menstruating Women Has High Recurrence.

    Science.gov (United States)

    Mehta, Christopher K; Stanifer, Bryan P; Fore-Kosterski, Susan; Gillespie, Colin; Yeldandi, Anjana; Meyerson, Shari; Odell, David D; DeCamp, Malcolm M; Bharat, Ankit

    2016-10-01

    Primary spontaneous pneumothorax (PSP) is treated on the basis of studies that have predominantly consisted of tall male subjects. Here, we determined recurrence of PSP in average-statured menstruating women and studied prevalence of catamenial pneumothorax (CP) in this population. Men and menstruating women, aged 18 to 55 years, without underlying lung disease or substance abuse were retrospectively studied between 2009 and 2015. A chest pathologist reviewed all specimens for thoracic endometriosis. Kaplan-Meier curves were constructed to determine recurrence. The median age of women (n = 33) and men (n = 183) was 33.4 and 31.6 years, respectively. In women, 9 (27%) had left-sided and 24 (73%) had right-sided PSP, treated with tube thoracostomy. Recurrence occurred in 21 women (64%) with median follow-up of 14 months, and they were treated with thoracoscopic pleurodesis. Right PSP had higher recurrence (70%) than left PSP (56%, p = 0.02). Four women (12%) presented with recurrent tension pneumothorax within 6 months. Eight patients (24%) had PSP within 72 hours of menses, meeting clinical criteria of CP. All these were placed on hormonal suppression after initial episode but went on to experience recurrence that was treated with pleurodesis. Classical endometrial glands were not found in any biopsy specimens obtained during the thoracoscopy. In contrast to female subjects, only 8 average-statured men (4.4%) had recurrence (p < 0.001) with a median follow-up of 16 months. PSP in healthy average-statured menstruating women has high recurrence compared with male counterparts. CP is a clinical diagnosis and often recurs despite hormonal suppression therapy. Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  15. Determinants of recurrence after intended curative resection for colorectal cancer

    DEFF Research Database (Denmark)

    Wilhelmsen, Michael; Kring, Thomas; Jorgensen, Lars N

    2014-01-01

    Despite intended curative resection, colorectal cancer will recur in ∼45% of the patients. Results of meta-analyses conclude that frequent follow-up does not lead to early detection of recurrence, but improves overall survival. The present literature shows that several factors play important roles...... in development of recurrence. It is well established that emergency surgery is a major determinant of recurrence. Moreover, anastomotic leakages, postoperative bacterial infections, and blood transfusions increase the recurrence rates although the exact mechanisms still remain obscure. From pathology studies...

  16. Sperm DNA fragmentation, recurrent implantation failure and recurrent miscarriage

    Directory of Open Access Journals (Sweden)

    Carol Coughlan

    2015-01-01

    Full Text Available Evidence is increasing that the integrity of sperm DNA may also be related to implantation failure and recurrent miscarriage (RM. To investigate this, the sperm DNA fragmentation in partners of 35 women with recurrent implantation failure (RIF following in vitro fertilization, 16 women diagnosed with RM and seven recent fathers (control were examined. Sperm were examined pre- and post-density centrifugation by the sperm chromatin dispersion (SCD test and the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL assay. There were no significant differences in the age of either partner or sperm concentration, motility or morphology between three groups. Moreover, there were no obvious differences in sperm DNA fragmentation measured by either test. However, whilst on average sperm DNA fragmentation in all groups was statistically lower in prepared sperm when measured by the SCD test, this was not seen with the results from the TUNEL assay. These results do not support the hypothesis that sperm DNA fragmentation is an important cause of RIF or RM, or that sperm DNA integrity testing has value in such patients. It also highlights significant differences between test methodologies and sperm preparation methods in interpreting the data from sperm DNA fragmentation tests.

  17. [Recurrent clinical mastitis in dairy cattle - importance and causes].

    Science.gov (United States)

    Grieger, A-S; Zoche-Golob, V; Paduch, J-H; Hoedemaker, M; Krömker, V

    2014-01-01

    Clinical mastitis as a frequently recurrent event can cause substantive economic loss on dairy farms. The reason for recurrent mastitis can be either a persistent infection of the bovine mammary gland by a mastitis pathogen or a reinfection of a quarter or udder after bacteriological cure. The virulence properties of a mastitis pathogen and the cure odds of an individual cow determine the development of persistent infections. Clinical episodes may alternate with periods without symptoms in the course of persistent infections. Strategies to reduce cases of recurrent mastitis have to include improved treatment concepts and measures to decrease new infection rates. The present literature review summarises the knowledge of definitions, frequencies, causes and effects of recurrent mastitis.

  18. 40 CFR 1048.635 - What special provisions apply to branded engines?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false What special provisions apply to branded engines? 1048.635 Section 1048.635 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Compliance Provisions § 1048.635 What special provisions apply to branded engines? The following provisions...

  19. Non-invasive physical treatments for chronic/recurrent headache.

    NARCIS (Netherlands)

    Bronfort, G.; Nilsson, N.; Haas, M.; Evans, R.; Goldsmith, C. H.; Assendelft, W. J.; Bouter, L. M.

    2004-01-01

    BACKGROUND: Non-invasive physical treatments are often used to treat common types of chronic/recurrent headache. OBJECTIVES: To quantify and compare the magnitude of short- and long-term effects of non-invasive physical treatments for chronic/recurrent headaches. SEARCH STRATEGY: We searched the

  20. Non-invasive physical treatments for chronic/recurrent headache

    NARCIS (Netherlands)

    Brønfort, Gert; Haas, Mitchell; Evans, Roni L.; Goldsmith, Charles H.; Assendelft, Willem J.J.; Bouter, Lex M.

    2014-01-01

    Background: Non-invasive physical treatments are often used to treat common types of chronic/recurrent headache. Objectives: To quantify and compare the magnitude of short- and long-term effects of non-invasive physical treatments for chronic/recurrent headaches. Search methods: We searched the

  1. Magnetic Resonance Imaging Findings Predict the Recurrence of Chronic Subdural Hematoma

    Science.gov (United States)

    GOTO, Haruo; ISHIKAWA, Osamu; NOMURA, Masashi; TANAKA, Kentaro; NOMURA, Seiji; MAEDA, Keiichiro

    2015-01-01

    The exact predictive factors for postoperative recurrence of chronic subdural hematoma (CSDH) are still unknown. Based on the preoperative magnetic resonance imaging (MRI), low recurrence rate of T1-hyperintensity hematoma was previously reported. We investigated the other types of radiological findings which are related to the recurrence rate of CSDH in large number of patients analyzed by multivariate logistic regression model. Preoperative MRI and postoperative computed tomography (CT) were performed and the influence of the preoperative use of antiplatelet or anticoagulant drugs was also studied. The overall recurrence rate was 9.3% (47 of 505 hematomas). The MRI T1-iso/hypointensity group showed a significantly higher recurrence rate (18.2%, 29 of 159) compared to the other groups (5.2%, 18 of 346; p hematoma, antiplatelet or anticoagulant drug usage, residual hematoma on postoperative CT, and MRI classification (p hematoma and antiplatelet or anticoagulant drug usage did not increase the recurrence risk. The preoperative MRI findings, especially T1WI findings, have predictive value for postoperative recurrence of CSDH and the T1-iso/hypointensity group can be assumed to be a high recurrence risk group. PMID:25746312

  2. Prevention of recurrent urinary tract infections in women.

    Science.gov (United States)

    2013-06-01

    Around 40-50% of women experience at least one urinary tract infection (UTI) during their lifetime and 20-30% of these have a recurrence within 3-4 months of the initial infection.¹ Recurrent UTI (usually defined as three episodes in the last 12 months or two episodes in the last 6 months) can have a considerable impact on a woman's quality of life. Each episode of acute UTI in young women is typically associated with about 6 days of symptoms, 2.4 days of restricted activities and 0.4 days of bed rest.¹ Antibacterial prophylaxis is effective in preventing recurrent episodes, but at the expense of unwanted effects and a risk of promoting bacterial resistance. Here we assess the efficacy of different antibacterial regimens and non-antibacterial alternatives (cranberry, probiotics, oestrogens, immunostimulation, hyaluronic acid and chondroitin, acupuncture and herbs) in the prevention of recurrent uncomplicated UTIs in women.

  3. Recurrent Aspiration Pneumonia due to Anterior Cervical Osteophyte

    Directory of Open Access Journals (Sweden)

    Jae Jun Lee

    2017-02-01

    Full Text Available A 74-year-old man presented with recurrent vomiting and aspiration pneumonia in the left lower lobe. He entered the intensive care unit to manage the pneumonia and septic shock. Although a percutaneous endoscopic gastrostomy tube was implanted for recurrent vomiting, vomiting and aspiration recurred frequently during admission. Subsequently, he complained of neck pain when in an upright position. A videofluoroscopic swallowing study showed compression of the esophagus by cervical osteophytes and tracheal aspiration caused by an abnormality at the laryngeal inlet. Cervical spine X-rays and computed tomography showed anterior cervical osteophytes at the C3-6 levels. Surgical decompression was scheduled, but was cancelled due to his frailty. Unfortunately, further recurrent vomiting and aspiration resulted in respiratory arrest leading to hypoxic brain damage and death. Physicians should consider cervical spine disease, such as diffuse skeletal hyperostosis as an uncommon cause of recurrent aspiration pneumonia.

  4. Management of Recurrent Subdural Hematomas.

    Science.gov (United States)

    Desai, Virendra R; Scranton, Robert A; Britz, Gavin W

    2017-04-01

    Subdural hematomas commonly recur after surgical evacuation, at a rate of 2% to 37%. Risk factors for recurrence can be patient related, radiologic, or surgical. Patient-related risk factors include alcoholism, seizure disorders, coagulopathy, and history of ventriculoperitoneal shunt. Radiologic factors include poor brain reexpansion postoperatively, significant subdural air, greater midline shift, heterogeneous hematomas (layered or multi-loculated), and higher-density hematomas. Surgical factors include lack of or poor postoperative drainage. Most recurrent hematomas are managed successfully with burr hole craniostomies with postoperative closed-system drainage. Refractory hematomas may be managed with a variety of techniques, including craniotomy or subdural-peritoneal shunt placement. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Recurrent intramedullary epidermoid cyst of conus medullaris.

    LENUS (Irish Health Repository)

    Fleming, Christina

    2011-01-01

    Spinal intramedullary epidermoid cyst is a rare condition. Recurrent epidermoid cyst in the spine cord is known to occur. The authors describe a case of recurrent conus medullaris epidermoid cyst in a 24-year-old female. She initially presented at 7 years of age with bladder disturbance in the form of diurnal enuresis and recurrent urinary tract infection. MRI lumbar spine revealed a 4 cm conus medullaris epidermoid cyst. Since the initial presentation, the cyst had recurred seven times in the same location and she underwent surgical intervention in the form of exploration and debulking. This benign condition, owing to its anatomical location, has posed a surgical and overall management challenge. This occurrence is better managed in a tertiary-care centre requiring multi-disciplinary treatment approach.

  6. 40 CFR 1051.645 - What special provisions apply to branded engines?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false What special provisions apply to branded engines? 1051.645 Section 1051.645 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Provisions § 1051.645 What special provisions apply to branded engines? The following provisions apply if you...

  7. Vaginal vault recurrences of endometrial cancer in non-irradiated patients

    DEFF Research Database (Denmark)

    Hardarson, Hordur Alexander; Nyhøj Heidemann, Lene; Christensen, René dePont

    2015-01-01

    are few and limited to previously irradiated patients or patients with advanced disease. Investigation of surgical treatment for isolated vaginal vault recurrence is practically nonexistent. The aim of this study is to evaluate the efficacy of RT and ST in a non-irradiated group with recurrent endometrial...... cancer limited to the vaginal vault. METHODS: Patients treated for recurrent endometrial cancer at Odense University Hospital, Denmark between 2003 and 2012 were identified, n = 118. Thirty-three patients had an isolated vaginal vault recurrence and were treated with either RT, ST or both. Re...

  8. Financial provisions for decommissioning and disposal: the operators' view

    International Nuclear Information System (INIS)

    Mueller-Dehn, C.

    2008-01-01

    The German system of making provisions for nuclear power has been the subject of frequent examinations, and has been approved in each case - by the German federal government, the European Commission, the Court of First Instance of the European Communities and, recently, also by the European Court of Justice. The article describes the basic legal principles entailing the obligation to make financial provisions for decommissioning and disposal by setting aside the required funds in line with current practice. The management of the assets balancing the provisions, the system of controls, the economic strength of the firms involved and, especially, the demand for the product they sell, i.e. electricity, ensure permanent availability of these funds. Numerous subsidiary legal provisions ensure transparency of these financial provisions. The external fund model analyzed as an alternative is the rejected both on account of drawbacks in its contents and for legal reasons. Attention is paid to the recommendation by the European Commission of October 2006 about financial provisions for decommissioning and disposal, to which the German system conforms and which does not require the establishment of external funds either. As the system of financial provisions has been operated successfully and reliably in Germany since the beginnings of the use of nuclear power, a plea is made in favor of upholding its structures and functions. (orig.)

  9. Recurrent oral angioleiomyoma

    Directory of Open Access Journals (Sweden)

    V G Mahima

    2011-01-01

    Full Text Available Angioleiomyomas are vascular variant of leiomyomas which are benign tumors of smooth muscle. They are exceedingly rare in the oral cavity. Malignant transformation of these tumors has also been reported occasionally which warrants knowledge of this soft tissue tumor. A 57 year old male patient reported with a 15 day history of an asymptomatic growth that had started insidiously in his lower left back tooth region. Clinical examination revealed a solitary, oval, sessile growth in the mandibular left retro molar region. Excisional biopsy was suggestive of Angioleiomyoma. A recurrence of the same was noted two months later which was also histopathologically reported as Angioleiomyoma. The same was confirmed using special stains. This case reports an unusual presentation of Angioleiomyoma with regards to both recurrence as well as rapid growth. It is important to be well aware of this uncommon entity as these tumors often can mimic or transform into malignancy. Precise clinicopathological examinations are therefore invaluable in establishing an accurate diagnosis and delivering suitable treatment.

  10. No. 250-Recurrent Urinary Tract Infection.

    Science.gov (United States)

    Epp, Annette; Larochelle, Annick

    2017-10-01

    To provide an update of the definition, epidemiology, clinical presentation, investigation, treatment, and prevention of recurrent urinary tract infections in women. Continuous antibiotic prophylaxis, post-coital antibiotic prophylaxis, and acute self-treatment are all efficient alternatives to prevent recurrent urinary tract infection. Vaginal estrogen and cranberry juice can also be effective prophylaxis alternatives. A search of PubMed and The Cochrane Library for articles published in English identified the most relevant literature. Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. There were no date restrictions. This update is the consensus of the Sub-Committee on Urogynaecology of the Society of Obstetricians and Gynaecologists of Canada. Recommendations were made according to the guidelines developed by the Canadian Task Force on Preventive Health Care (Table 1). Recurrent urinary tract infections need careful investigation and can be efficiently treated and prevented. Different prophylaxis options can be selected according to each patient's characteristics. Copyright © 2017. Published by Elsevier Inc.

  11. Recurrence analysis of ant activity patterns.

    Directory of Open Access Journals (Sweden)

    Felipe Marcel Neves

    Full Text Available In this study, we used recurrence quantification analysis (RQA and recurrence plots (RPs to compare the movement activity of individual workers of three ant species, as well as a gregarious beetle species. RQA and RPs quantify the number and duration of recurrences of a dynamical system, including a detailed quantification of signals that could be stochastic, deterministic, or both. First, we found substantial differences between the activity dynamics of beetles and ants, with the results suggesting that the beetles have quasi-periodic dynamics and the ants do not. Second, workers from different ant species varied with respect to their dynamics, presenting degrees of predictability as well as stochastic signals. Finally, differences were found among minor and major caste of the same (dimorphic ant species. Our results underscore the potential of RQA and RPs in the analysis of complex behavioral patterns, as well as in general inferences on animal behavior and other biological phenomena.

  12. Dynamic selection mechanism for quality of service aware web services

    Science.gov (United States)

    D'Mello, Demian Antony; Ananthanarayana, V. S.

    2010-02-01

    A web service is an interface of the software component that can be accessed by standard Internet protocols. The web service technology enables an application to application communication and interoperability. The increasing number of web service providers throughout the globe have produced numerous web services providing the same or similar functionality. This necessitates the use of tools and techniques to search the suitable services available over the Web. UDDI (universal description, discovery and integration) is the first initiative to find the suitable web services based on the requester's functional demands. However, the requester's requirements may also include non-functional aspects like quality of service (QoS). In this paper, the authors define a QoS model for QoS aware and business driven web service publishing and selection. The authors propose a QoS requirement format for the requesters, to specify their complex demands on QoS for the web service selection. The authors define a tree structure called quality constraint tree (QCT) to represent the requester's variety of requirements on QoS properties having varied preferences. The paper proposes a QoS broker based architecture for web service selection, which facilitates the requesters to specify their QoS requirements to select qualitatively optimal web service. A web service selection algorithm is presented, which ranks the functionally similar web services based on the degree of satisfaction of the requester's QoS requirements and preferences. The paper defines web service provider qualities to distinguish qualitatively competitive web services. The paper also presents the modelling and selection mechanism for the requester's alternative constraints defined on the QoS. The authors implement the QoS broker based system to prove the correctness of the proposed web service selection mechanism.

  13. Access control infrastructure for on-demand provisioned virtualised infrastructure services

    NARCIS (Netherlands)

    Demchenko, Y.; Ngo, C.; de Laat, C.; Smari, W.W.; Fox, G.C.

    2011-01-01

    Cloud technologies are emerging as a new way of provisioning virtualised computing and infrastructure services on-demand for collaborative projects and groups. Security in provisioning virtual infrastructure services should address two general aspects: supporting secure operation of the provisioning

  14. Safety, Efficacy and Recurrence rate following tenosynovectomy and ...

    African Journals Online (AJOL)

    Objective: This study was conducted to compare the safety, efficacy and recurrence rate of primary tenosynovectomy versus intralesional steroid injection in the treatment of sclerosing tenosynovitis of deQuervain. Method: A prospective, comparative study of the safety, efficacy and recurrence rate following intralesional ...

  15. Diseño experimental de un Modelo de Calidad de Servicio para Redes de Siguiente Generación

    Directory of Open Access Journals (Sweden)

    Josheff David

    2015-07-01

    Full Text Available Este artículo presenta un Modelo de Calidad de Servicio (QoS para Redes de Siguiente Generación (NGN, que consta de una torre de cinco capas definidas como Capa Modelo de QoS, Control de Admisión, QoS en el Enrutamiento, QoS en la Señalización, y MAC QoS. Además el modelo plantea un método basado en el concepto de segregación de funciones definiendo dos redes funcionales junto con las tareas de QoS. Luego se establecen las políticas de Control de Acceso, los protocolos y algoritmos de señalización, y de enrutamiento, así como los aspectos relacionados con el acceso al medio. Para verificar el rendimiento del modelo, se realizó un Diseño de Experimentos sobre una NGN Piloto en la herramienta de simulación OPNET Modeler. El Análisis Estadístico constó de un Análisis de Varianzas sobre las variables de salida Retardo, Jitter y Throughput, cuyo resultado determinó los factores significativos de impacto del modelo en las métricas estudiadas.   Abstract This paper presents a Model of Quality of Service (QoS for Next Generation Networks (NGN, which consists of a tower of five layers defined as Model Layer QoS, Admission Control, QoS routing, QoS signaling, MAC and QoS. The model also presents a method based on the concept of segregation of functions defining two functional networks with QoS tasks. Then, Access Control policies, protocols and algorithms, signaling and routing, as well as aspects related to media access are established. To verify the performance of the model, a Design of Experiments on a NGN Pilot was designed over simulation tool OPNET Modeler. The statistical analysis consisted of an analysis of variance on the output variables Delay, Jitter and Throughput, whose outcome determined the significant factors that impacted the model metrics.

  16. Assessing the risk of recurrent venous thromboembolism – a practical approach

    Science.gov (United States)

    Fahrni, Jennifer; Husmann, Marc; Gretener, Silvia B; Keo, Hong H

    2015-01-01

    Recurrent venous thromboembolism (VTE) is associated with increased morbidity and mortality. This risk is lowered by anticoagulation, with a large effect in the initial phase following the venous thromboembolic event, and with a smaller effect in terms of secondary prevention of recurrence when extended anticoagulation is performed. On the other hand, extended anticoagulation is associated with an increased risk of major bleeding and thus leads to morbidity and mortality. Therefore, it is necessary to assess the risk of recurrence for VTE on an individual basis, and a recommendation for secondary prophylaxis should be specifically based on risk calculation of recurrence of VTE and bleeding. In this review, we provide a comprehensive summary of relevant risk factors for recurrent VTE and a practical approach for assessing the risk of recurrence in daily practice. PMID:26316770

  17. Recurrence relations in the three-dimensional Ising model

    International Nuclear Information System (INIS)

    Yukhnovskij, I.R.; Kozlovskij, M.P.

    1977-01-01

    Recurrence relations between the coefficients asub(2)sup((i)), asub(4)sup((i)) and Psub(2)sup((i)), Psub(4)sup((i)) which characterize the probabilities of distribution for the three-dimensional Ising model are studied. It is shown that for large arguments z of the Makdonald functions Ksub(ν)(z) the recurrence relations correspond to the known Wilson relations. But near the critical point for small values of the transfer momentum k this limit case does not take place. In the pointed region the argument z tends to zero, and new recurrence relations take place

  18. Radiofrequency Ablation Effectively Treated Focal Recurrence of Mesothelioma.

    Science.gov (United States)

    Nakamura, Akifumi; Takuwa, Teruhisa; Hashimoto, Masaki; Kondo, Nobuyuki; Takaki, Haruyuki; Fujiwara, Masayuki; Yamakado, Koichiro; Hasegawa, Seiki

    2018-02-01

    A 55-year-old man with malignant pleural mesothelioma underwent multimodality treatment comprising induction chemotherapy followed by extrapleural pneumonectomy and radiation therapy. After 2.5 years, focal recurrence occurred, with computed tomography revealing a tumor in the left cardiophrenic angle. Surgery was considered a problem for the patient because of the previous extrapleural pneumonectomy and difficult tumor location. Radiofrequency ablation was thus performed; the course was uneventful, and there was no recurrence. Radiofrequency ablation should be considered an option to treat recurrence of malignant pleural mesothelioma. Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  19. Recurrent Guillain-Barré syndrome, Miller Fisher syndrome and Bickerstaff brainstem encephalitis.

    Science.gov (United States)

    Ishii, Junko; Yuki, Nobuhiro; Kawamoto, Michi; Yoshimura, Hajime; Kusunoki, Susumu; Kohara, Nobuo

    2016-05-15

    Guillain-Barré syndrome (GBS), Miller Fisher syndrome (MFS), and Bickerstaff brainstem encephalitis (BBE) are usually monophasic, but some patients experience recurrences after long asymptomatic intervals. We aimed to investigate clinical features of recurrent GBS, MFS, and BBE at a single hospital. Records from 97 consecutive patients with GBS, MFS or BBE who were admitted to a tertiary hospital between 2001 and 2013 were reviewed. Clinical and laboratory features of patients with recurrent GBS, MFS, or BBE were investigated. Patients included 55 (32 males) with GBS, 34 (22 males) with MFS, and 8 (6 males) with BBE. Recurrent cases occurred in 2 (4%) of the 55 patients with GBS, 4 (12%) of the 34 patients with MFS, and 2 (25%) of the 8 patients with BBE. Patients with recurrent MFS had a tendency to be younger at the first episode than patients with non-recurrent MFS (median, 22 versus 37years old). Symptoms and signs were less severe during relapses than during the initial episode in recurrent patients. Recurrences occurred more frequently in patients with MFS or BBE compared with those with GBS. Patients with recurrent MFS might be younger than those with non-recurrent MFS. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Mitigating Provider Uncertainty in Service Provision Contracts

    Science.gov (United States)

    Smith, Chris; van Moorsel, Aad

    Uncertainty is an inherent property of open, distributed and multiparty systems. The viability of the mutually beneficial relationships which motivate these systems relies on rational decision-making by each constituent party under uncertainty. Service provision in distributed systems is one such relationship. Uncertainty is experienced by the service provider in his ability to deliver a service with selected quality level guarantees due to inherent non-determinism, such as load fluctuations and hardware failures. Statistical estimators utilized to model this non-determinism introduce additional uncertainty through sampling error. Inability of the provider to accurately model and analyze uncertainty in the quality level guarantees can result in the formation of sub-optimal service provision contracts. Emblematic consequences include loss of revenue, inefficient resource utilization and erosion of reputation and consumer trust. We propose a utility model for contract-based service provision to provide a systematic approach to optimal service provision contract formation under uncertainty. Performance prediction methods to enable the derivation of statistical estimators for quality level are introduced, with analysis of their resultant accuracy and cost.