Neutrophil Oxygen Radical Production by Dialysis Membranes

The ability of different dialysis membranes to activate polymorphonuclear neutrophil oxygen radical production was investigated with chemiluminescence. All the six membranes, namely cuprophan, cellulose acetate, polycarbonate, polysulphone, polyacrilonitrile and polymethylmethacrylate were able to interact with neutrophils and stimulate their oxygen radical production, the highest responses being seen with polyacrilonitrile, polymethylmethacrylate and polycarbonate. To analyse the role of complement in this interaction, fresh plasma, heat inactivated and zymosan-activated plasma were added: with fresh plasma oxygen radical production was stimulated on cuprophan, cellulose acetate and polysulphone, not modified on polycarbonate, and decreased on polyacrilonitrile and polymethylmethacrylate. With heat-inactivated plasma, the responses were decreased or abrogated on all the membranes except polycarbonate and polymethylmethacrylate, whereas with zymosanactivated plasma similar responses to fresh plasma were observed. In addition, when plasma was used to precoat the membrane, cuprophan, cellulose acetate and polysulphone disclosed an enhanced neutrophil oxidative burst, while precoated polyacrilonitrile and polymethylmethacrylate were less stimulatory than uncoated membranes. In contrast the precoating of polycarbonate did not modify oxygen radical production. These data suggest that neutrophil activation occurs by direct membrane neutrophil interaction. Plasmatic factors modulate this interaction but complement seems involved on cellulosic and polysulphone membranes only. Therefore, it appears that oxygen radicals produced from contact of neutrophils with the dialysis membrane might play an initial and/or additional role in the events occurring at the initiation of haemodialysi

Performance of Geant4 in simulating semiconductor particle detector response in the energy range below 1 MeV

Geant4 simulations play a crucial role in the analysis and interpretation of experiments providing low energy precision tests of the Standard Model. This paper focuses on the accuracy of the description of the electron processes in the energy range between 100 and 1000 keV. The effect of the different simulation parameters and multiple scattering models on the backscattering coefficients is investigated. Simulations of the response of HPGe and passivated implanted planar Si detectors to \beta{} particles are compared to experimental results. An overall good agreement is found between Geant4 simulations and experimental data

On the Mechanisms of Haemodialysis-induced Neutropenia: A Study with Five New and Re-used Membranes

A prospective study was undertaken in 12 haemodialysed patients successively treated on five new as well as re-used dialyser membranes, that is cuprophane, cellulose acetate, polysulphone, polycarbonate, and polyacrylonitrile. A significant reduction of neutrophils occurred with every membrane during their first use, which improved only with cuprophane upon re-use. Thrombocytopenia was noted only when neutropenia reached very low values. Monocyte reduction occurred on cuprophane, cellulose acetate and polycarbonate, but did not improve during second use. C3d accumulation paralleled the time course of neutropenia only with cuprophane and cellulose acetate. Plasma collected at the extreme of neutropenia induced aggregation of control and predialysis cells, but did not aggregate autologous dialysed neutrophils collected at 5 min. Our data indicate that the mechanism linking complement activation to neutropenia is probably triggered by more than one facto

Shape Coexistence in Pb186: Beyond-mean-field description by configuration mixing of symmetry restored wave functions

We study shape coexistence in Pb186 using configuration mixing of angular-momentum and particle-number projected self-consistent mean-field states. The same Skyrme interaction SLy6 is used everywhere in connection with a density-dependent zero-range pairing force. The model predicts coexisting spherical, prolate and oblate 0+ states at low energy.Comment: 5 pages REVTEX4, 4 eps figures, accepted by Phys. Lett. B. Revised version with some polishing of the text without changing its conten

Network-based dynamic prioritization of HTTP adaptive streams to avoid video freezes

HTTP Adaptive Streaming (HAS) is becoming the de-facto standard for video streaming services over the Internet. In HAS, each video is segmented and stored in different qualities. Rate adaptation heuristics, deployed at the client, allow the most appropriate quality level to be dynamically requested, based on the current network conditions. Current heuristics under-perform when sudden bandwidth drops occur, therefore leading to freezes in the video play-out, the main factor influencing users' Quality of Experience (QoE). In this article, we propose an Openflow-based framework capable of increasing clients' QoE by reducing video freezes. An Openflow-controller is in charge of introducing prioritized delivery of HAS segments, based on feedback collected from both the network nodes and the clients. To reduce the side-effects introduced by prioritization on the bandwidth estimation of the clients, we introduce a novel mechanism to inform the clients about the prioritization status of the downloaded segments without introducing overhead into the network. This information is then used to correct the estimated bandwidth in case of prioritized delivery. By evaluating this novel approach through emulation, under varying network conditions and in several multi-client scenarios, we show how the proposed approach can reduce freezes up to 75% compared to state-of-the-art heuristics

The potential of mathematical picture books: a systematic analysis of their domain-specific picture book features

Studies in the domain of early literacy and recently also mathematics point to the potential of picture book reading (PBR) activities for children’s early literacy resp. mathematical development. Contrasting the domain of early literacy, the contribution of picture book features to the effectiveness of PBR activities in the domain of mathematics is hardly studied. To increase our understanding of the topic, we systematically analysed the domain-specific features of 100 mathematical picture books. Our analyses pointed to the presence of features that previous studies assume to support and to hinder early mathematical development (Ward et al., 2017). These findings complement previous findings based on English mathematical picture books from the U.S. and offer important insights for future studies and educational practice