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This paper describes WOW, a distributed system that combines virtual machine, overlay networking and peer-to-peer techniques to create scalable wide-area networks of virtual workstations for high-throughput computing. The system is architected to: facilitate the addition of nodes to a pool of resources through the use of system virtual machines (VMs) and self-organizing virtual network links; to maintain IP connectivity even if VMs migrate across network domains; and to present to end-users and applications an environment that is functionally identical to a local-area network or cluster of workstations. We describe IPOP, a network virtualization technique that builds upon a novel, extensible user-level decentralized technique to discover, establish and maintain overlay links to tunnel IP packets over different transports (including UDP and TCP) and across firewalls. We evaluate latency and bandwidth overheads of IPOP and also time taken for a new node to become fully-routable over the virtual network. We also report on several experiments conducted on a testbed WOW deployment with 118 P2P router nodes over PlanetLab and 33 VMware-based VM nodes distributed across six firewalled domains. Experiments show that the testbed delivers good performance for two unmodified, representative benchmarks drawn from the life-sciences domain. We also demonstrate that the system is capable of seamlessly maintaining connectivity at the virtual IP layer for typical client/server applications (NFS, SSH, PBS) when VMs migrate across a WAN. [ABSTRACT FROM AUTHOR]

Considering the complexity of the immunological events triggered during active visceral Leishmaniasis (VL), the relevance of the segregation of the immune response during human VL into type 1 and type 2 still remains unclear. For this purpose, in individuals living in risk areas for VL, we have evaluated especially asymptomatic individuals and patients with active VL, the plasmatic levels of cytokines and reactive nitrogen species under ex vivo conditions. In addition, we have also performed an analysis of intracellular cytokine patterns of circulating leucocytes after short-term culture, particularly in the absence of antigenic-specific stimulation, in order to reflect dynamic events of immune response in vivo during Leishmania chagasi infection. Although asymptomatic individuals and non-infected subjects presented a similar immunological profile, an outstanding inflammatory/regulatory profile, based on higher plasmatic levels of cytokines such as interleukin (IL)-8, interferon (IFN)-γ, tumour necrosis factor (TNF)-α, IL-6 and IL-10, was associated with clinical status observed in active VL. In this context, we hypothesize that IL-10, through its ability to inhibit anti-leishmanial macrophage activation, associated with the lower frequency of TNF-α+ monocytes and ordinary levels of nitrite and nitrate are the major mechanisms associated with disease onset. [ABSTRACT FROM AUTHOR]

We investigated the cytokine profile of cells of the innate immune response and its association with active (ACT), asymptomatic (AS) and cured (CUR) human visceral leishmaniasis (VL), as well as noninfected (NI) subjects. The frequency of cytokine-producing cells was determined after short-term in vitro incubation of whole peripheral blood samples with soluble Leishmania antigen (SLA). Our data demonstrated a predominant type 2 cytokine profile in NI and ACT. In NI, we observed an increase of IL-4+ neutrophils, IL-10+ eosinophils besides a decrease of tumour necrosis factor (TNF)-α+ eosinophils/monocytes. Yet in ACT, we observed an increase of IL-4+ neutrophils and natural killer (NK) cells and IL-10+ monocytes, a reduced frequency of IL-12+ and IFN-γ+ eosinophils and lower levels of TNF-α+ and IL-12+ monocytes. AS presented a mixed profile, characterized by an increase of IFN-γ+ neutrophils/eosinophils and NK cells, of IL-12+ eosinophils/monocytes, as well as increase of IL-4+ neutrophils and NK cells and IL-10+ eosinophils/monocytes. In contrast, CUR was characterized by a type 1 response with an increase of IFN-γ+ neutrophils/eosinophils and NK cells, associated with an increase in IL-12+ monocytes. In conclusion, we show a correlation between innate immune cytokine patterns and clinical status of VL, suggesting that these cells, in addition to other factors, may contribute to the cytokine microenvironment in which Leishmania-specific T cells are primed and to disease outcome. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To describe the incidence and clinical features of delayed-onset wound infections after lower third molar extractions in an outpatient clinic. STUDY DESIGN: Retrospective forward study of 958 lower third molar extractions in the Oral Surgery and Implantology Department of the School of Dentistry of the University of Barcelona (Spain). RESULTS: Fourteen delayed-onset wound infections were recorded after suture removal (1.5% of the extractions). These infections usually developed 3-5 weeks after extraction. Half of the cases presented a radiolucency around the crown of the third molar. In most cases, ostectomy (13/14) and tooth sectioning (11/14) had been made. CONCLUSIONS: Delayed infections were a rare postoperative complication of lower third molars extractions. Nevertheless, patients should be warned that infection can still occur several weeks after the surgical procedure. [ABSTRACT FROM AUTHOR]

e-lab is a remote laboratory platform that provides access to several remote experiments in basic or advanced physics . Recent upgrades to it's interface and new features introduced make it more accessible and appealing, but experiment's attractiveness for teachers and students has been an issue. A new experiment intended to improve this aspect was introduced: the World Pendulum. Consisting in multiple identical pendulum apparatuses connected to e-lab and scattered throughout different locations across several countries. The World Pendulum is intended at exploring a unique feature allowed by remote experimentation - experimental repetition in different locations. [ABSTRACT FROM AUTHOR]

The authors propose a transmitter digital filter for joint optimisation of signal pulse shaping and chromatic dispersion pre-compensation, providing a detailed analysis of the architecture complexity. Experimental transmission of 40 × 50G channels (28 Gbaud four-level pulse amplitude modulation) over up to 110 km uncompensated standard single mode fibre with low-bandwidth hardware is demonstrated. [ABSTRACT FROM AUTHOR]