Single system image: A survey

Single system image is a computing paradigm where a number of distributed computing resources are aggregated and presented via an interface that maintains the illusion of interaction with a single system. This approach encompasses decades of research using a broad variety of techniques at varying levels of abstraction, from custom hardware and distributed hypervisors to specialized operating system kernels and user-level tools. Existing classification schemes for SSI technologies are reviewed, and an updated classification scheme is proposed. A survey of implementation techniques is provided along with relevant examples. Notable deployments are examined and insights gained from hands-on experience are summarized. Issues affecting the adoption of kernel-level SSI are identified and discussed in the context of technology adoption literature

XMM-Newton observation of Abell 1835 : temperature, mass and gas mass fraction profiles

We present a study of the medium distant cluster of galaxies Abell 1835 based on XMM-Newton data. The high quality of XMM-Newton data enable us to perform spectro-imaging of the cluster up to large radii. We determine the gas and total mass profiles based on the hydrostatic approach using the beta-model and the temperature profile. For the determination of the temperature profile of the ICM, which is needed for the mass determination, we apply a double background subtraction, which accounts for the various kinds of background present (particle and astrophysical background). We find a basically flat temperature profile up to 0.75 r_200 with a temperature decrease towards the center linked to the cooling flow. We obtain a gas mass fraction of (20.7 +/- 3.7)%, which is a lower limit on the baryon fraction in this cluster. Using this value as baryon fraction for the entire universe, we obtain by combining our results with results based on primordial nucleosynthesis, an upper limit for Omega_m < 0.5h_{50}^{-1/2}, which is in good agreement with other recent studies.Comment: 12 pages, 16 figures and 3 tables, accepted for publication in Astronomy & Astrophysic

RXJ0256.5+0006: a merging cluster of galaxies at z=0.36 observed with XMM-Newton

(abridged) We present a study based on XMM data of RX J0256.5+0006, a medium distant (z=0.36) galaxy cluster found in the Bright SHARC catalog. The intracluster medium shows a bimodal structure: one main cluster component and a substructure in the west. Despite the indication of interaction we do not find any sign of temperature gradients. Due to the non-symmetric form of the main cluster we extract surface brightness profiles in different sectors around its centre. We see large variations between the profiles, which we quantify by beta-model fitting. The corresponding r_c's vary between 0.1-0.5Mpc and the beta's between 0.5-1.2. The variations of the beta-model parameters indicate that the main cluster is not entirely relaxed. This hypothesis is strengthened by the fact that the cluster is over-luminous with respect to the (z-evolving) L_x-T relation found for nearby clusters. Comparing our profiles to the reference emission measure profile of Arnaud et al., we find that only the profile extracted north-east (NE) of the main cluster centre is similar to this reference profile. This indicates that only the NE profile is representative for the relaxed part of this cluster component. Using this profile and the spectroscopically fitted temperature of T=4.9^+0.5_-0.4keV we find M_500~4 10^14 solar masses. This value is in agreement with the value obtained using the z-evolving M_500-T relation from the HIFLUGCS sample. For the gas mass fraction we find f_g~18-20% which is in good agreement with other work. We also develop a simple on-axis merger model for the cluster. Together with a simple ram pressure model we find that the most likely physical distance of the subcluster to the main cluster lies between 0.6<d<1.0Mpc. We find for the ratio of subcluster to main cluster mass values between 20-30%.Comment: 19 pages including 19 figures (including 4 figures in jpg and png format), accepted for publication in A&

Destructive arthritis in a patient with chikungunya virus infection with persistent specific IgM antibodies

<p>Abstract</p> <p>Background</p> <p>Chikungunya fever is an emerging arboviral disease characterized by an algo-eruptive syndrome, inflammatory polyarthralgias, or tenosynovitis that can last for months to years. Up to now, the pathophysiology of the chronic stage is poorly understood.</p> <p>Case presentation</p> <p>We report the first case of CHIKV infection with chronic associated rheumatism in a patient who developed progressive erosive arthritis with expression of inflammatory mediators and persistence of specific IgM antibodies over 24 months following infection.</p> <p>Conclusions</p> <p>Understanding the specific features of chikungunya virus as well as how the virus interacts with its host are essential for the prevention, treatment or cure of chikungunya disease.</p

Introduction—Food Security and Food Waste Reduction: A Social Innovation Approach to Current Social, Environmental, and Political Concerns

This chapter presents the research rationale underpinning the book. It addresses the intertwining challenges of food security and surplus food management, discussing recent data and literature. It also presents how social innovation is conceptualized in the book as the theoretical framework to analyse partnerships between business and non-profit organisations in managing food surplus. The methodology of the research is also detailed, along with the book structure

Cell Type–Specific Transcriptome Analysis Reveals a Major Role for Zeb1 and miR-200b in Mouse Inner Ear Morphogenesis

Cellular heterogeneity hinders the extraction of functionally significant results and inference of regulatory networks from wide-scale expression profiles of complex mammalian organs. The mammalian inner ear consists of the auditory and vestibular systems that are each composed of hair cells, supporting cells, neurons, mesenchymal cells, other epithelial cells, and blood vessels. We developed a novel protocol to sort auditory and vestibular tissues of newborn mouse inner ears into their major cellular components. Transcriptome profiling of the sorted cells identified cell type–specific expression clusters. Computational analysis detected transcription factors and microRNAs that play key roles in determining cell identity in the inner ear. Specifically, our analysis revealed the role of the Zeb1/miR-200b pathway in establishing epithelial and mesenchymal identity in the inner ear. Furthermore, we detected a misregulation of the ZEB1 pathway in the inner ear of Twirler mice, which manifest, among other phenotypes, malformations of the auditory and vestibular labyrinth. The association of misregulation of the ZEB1/miR-200b pathway with auditory and vestibular defects in the Twirler mutant mice uncovers a novel mechanism underlying deafness and balance disorders. Our approach can be employed to decipher additional complex regulatory networks underlying other hearing and balance mouse mutants