671 research outputs found

    The effect of handover quality on buffering requirements in WATM

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    COVNET : A cooperative coevolutionary model for evolving artificial neural networks

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    This paper presents COVNET, a new cooperative coevolutionary model for evolving artificial neural networks. This model is based on the idea of coevolving subnetworks. that must cooperate to form a solution for a specific problem, instead of evolving complete networks. The combination of this subnetwork is part of a coevolutionary process. The best combinations of subnetworks must be evolved together with the coevolution of the subnetworks. Several subpopulations of subnetworks coevolve cooperatively and genetically isolated. The individual of every subpopulation are combined to form whole networks. This is a different approach from most current models of evolutionary neural networks which try to develop whole networks. COVNET places as few restrictions as possible over the network structure, allowing the model to reach a wide variety of architectures during the evolution and to be easily extensible to other kind of neural networks. The performance of the model in solving three real problems of classification is compared with a modular network, the adaptive mixture of experts and with the results presented in the bibliography. COVNET has shown better generalization and produced smaller networks than the adaptive mixture of experts and has also achieved results, at least, comparable with the results in the bibliography

    Regulation of stanniocalcin-1 secretion by BeWo cells and first trimester human placental tissue from normal pregnancies and those at increased risk of developing preeclampsia.

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    Stanniocalcin-1 (STC-1) is a multi-functional glycosylated peptide present in the plasma of healthy women postpartum and increased further in pregnancies complicated by preeclampsia. Although the STC-1 gene is expressed by the placenta what regulates its secretion and from which cells at the feto-maternal interface is unknown. Here, we demonstrate for the first time that the syncytiotrophoblast and cytotrophoblast are a major site of STC-1 protein expression in first trimester placental tissue. Further, in response to low oxygen, first trimester chorionic villous tissue from pregnancies at increased risk of developing preeclampsia secreted significantly more STC-1 than normal tissue under the same conditions. Using the human trophoblast cell line BeWo we have shown that low oxygen increased the secretion of STC-1 but it required co-stimulation with the Adenosine-3', 5'-cyclic monophosphate (cAMP) analogue, 8-Bromo adenosine-3', 5'-cyclic monophosphate cAMP (8 Br-cAMP) to reach significance. Inhibition of Hypoxia inducible factor 2α (HIF-2α) and the Phosphatidylinositol-3 kinase (PI3 -Kinase)/AKT/Serum and glucocorticoid-induced kinase-1(SGK-1) pathway resulted in significant inhibition of STC-1 secretion. As both low oxygen and cAMP are known to play a central role in placental function, their regulation of STC-1 points to a potentially important role in the maintenance of a normal healthy pregnancy and we would hypothesize that it may act to protect against prolonged placental hypoxia seen in preeclampsia

    Kinetic and structural mechanism for DNA unwinding by a non-hexameric helicase

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    UvrD, a model for non-hexameric Superfamily 1 helicases, utilizes ATP hydrolysis to translocate stepwise along single-stranded DNA and unwind the duplex. Previous estimates of its step size have been indirect, and a consensus on its stepping mechanism is lacking. To dissect the mechanism underlying DNA unwinding, we use optical tweezers to measure directly the stepping behavior of UvrD as it processes a DNA hairpin and show that UvrD exhibits a variable step size averaging ~3 base pairs. Analyzing stepping kinetics across ATP reveals the type and number of catalytic events that occur with different step sizes. These single-molecule data reveal a mechanism in which UvrD moves one base pair at a time but sequesters the nascent single strands, releasing them non-uniformly after a variable number of catalytic cycles. Molecular dynamics simulations point to a structural basis for this behavior, identifying the protein-DNA interactions responsible for strand sequestration. Based on structural and sequence alignment data, we propose that this stepping mechanism may be conserved among other non-hexameric helicases

    Moving beyond disciplinary silos: The potential for transdisciplinary research in Sport for Development

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    The Sport for Development (SfD) field is transdisciplinary by nature, and yet scholars tend to stay within their disciplinary perspectives in their study of SfD. There is a need for more collaborative and collective approaches in SfD research. Transdisciplinary research facilitates conceptual, theoretical, philosophical, and methodological innovations that transcend disciplinary boundaries, creating new knowledge that can advance a field. The purpose of this paper is to critically review the disciplinary trends in SfD research within (respectively) sport sociology, social anthropology, sport management, public health, leisure, sport pedagogy, and sport psychology, with a particular focus on where there may be intersection, duplication, obfuscation, and omission between these disciplines. Disciplinary intersections are then considered, along with gaps in the SfD evidence base that are ripe for transdisciplinary research. The paper concludes with an exploration of possibilities for future transdisciplinary research in SfD

    Media coverage of climate change: an international comparison

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    We present an international comparison of broadsheet newspaper coverage of climate change. We employ two complementary theoretical lenses, multiple streams theory and institutional theory, to explore why climate change has become headline news in some countries but has received comparatively little coverage in others. The study utilises a worldwide sample across 41 different countries for the year 2008, covering 113 leading national broadsheet newspapers. A cross-sectional regression model is used to identify whether and how a range of contextual factors impact coverage of climate change. To a certain extent, a country’s direct exposure to climate change and the measures that have been taken to combat global warming influence the position of climate change on the media agenda. Crucially, however, we identify a number of contextual factors that impact climate change-related media coverage in different national contexts. In particular, we find a significantly positive relationship between regulatory quality and levels of media coverage. At the same time, unemployment trends are significantly negatively related to media attention to climate change. Gross domestic product per capita does not help to explain levels of climate change-related media coverage. In other words, climate change appears to have moved beyond simply being a ‘rich country issue’

    Clinical trial of laronidase in Hurler syndrome after hematopoietic cell transplantation.

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    BackgroundMucopolysaccharidosis I (MPS IH) is a lysosomal storage disease treated with hematopoietic cell transplantation (HCT) because it stabilizes cognitive deterioration, but is insufficient to alleviate all somatic manifestations. Intravenous laronidase improves somatic burden in attenuated MPS I. It is unknown whether laronidase can improve somatic disease following HCT in MPS IH. The objective of this study was to evaluate the effects of laronidase on somatic outcomes of patients with MPS IH previously treated with HCT.MethodsThis 2-year open-label pilot study of laronidase included ten patients (age 5-13 years) who were at least 2 years post-HCT and donor engrafted. Outcomes were assessed semi-annually and compared to historic controls.ResultsThe two youngest participants had a statistically significant improvement in growth compared to controls. Development of persistent high-titer anti-drug antibodies (ADA) was associated with poorer 6-min walk test (6MWT) performance; when patients with high ADA titers were excluded, there was a significant improvement in the 6MWT in the remaining seven patients.ConclusionsLaronidase seemed to improve growth in participants <8 years old, and 6MWT performance in participants without ADA. Given the small number of patients treated in this pilot study, additional study is needed before definitive conclusions can be made

    "Open Innovation" and "Triple Helix" Models of Innovation: Can Synergy in Innovation Systems Be Measured?

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    The model of "Open Innovations" (OI) can be compared with the "Triple Helix of University-Industry-Government Relations" (TH) as attempts to find surplus value in bringing industrial innovation closer to public R&D. Whereas the firm is central in the model of OI, the TH adds multi-centeredness: in addition to firms, universities and (e.g., regional) governments can take leading roles in innovation eco-systems. In addition to the (transversal) technology transfer at each moment of time, one can focus on the dynamics in the feedback loops. Under specifiable conditions, feedback loops can be turned into feedforward ones that drive innovation eco-systems towards self-organization and the auto-catalytic generation of new options. The generation of options can be more important than historical realizations ("best practices") for the longer-term viability of knowledge-based innovation systems. A system without sufficient options, for example, is locked-in. The generation of redundancy -- the Triple Helix indicator -- can be used as a measure of unrealized but technologically feasible options given a historical configuration. Different coordination mechanisms (markets, policies, knowledge) provide different perspectives on the same information and thus generate redundancy. Increased redundancy not only stimulates innovation in an eco-system by reducing the prevailing uncertainty; it also enhances the synergy in and innovativeness of an innovation system.Comment: Journal of Open Innovations: Technology, Market and Complexity, 2(1) (2016) 1-12; doi:10.1186/s40852-016-0039-

    Single-day therapy: an expert opinion on a recent development for the episodic treatment of recurrent genital herpes

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    One common method for treating recurrent genital herpes outbreaks is 3–5 day episodic therapy with nucleoside analogues. However, since maximum viral replication occurs within 24 h after the onset of symptoms, short-term patient-initiated episodic therapy started at prodromal onset or at the first appearance of lesions in patients without a prodrome may represent an important option. In a recent randomized trial, single-day famciclovir treatment decreased lesion healing time and the duration of pain and other symptoms by approximately 2 days compared to placebo, and prevented progression to a full outbreak in almost one in four patients. Because single-day treatment is more convenient than traditional therapies, it may lead to improved patient compliance and better overall management of recurrent genital herpes outbreaks
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