311 research outputs found

    Cost-Efficient Data Backup for Data Center Networks against {\epsilon}-Time Early Warning Disaster

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    Data backup in data center networks (DCNs) is critical to minimize the data loss under disaster. This paper considers the cost-efficient data backup for DCNs against a disaster with Δ\varepsilon early warning time. Given geo-distributed DCNs and such a Δ\varepsilon-time early warning disaster, we investigate the issue of how to back up the data in DCN nodes under risk to other safe DCN nodes within the Δ\varepsilon early warning time constraint, which is significant because it is an emergency data protection scheme against a predictable disaster and also help DCN operators to build a complete backup scheme, i.e., regular backup and emergency backup. Specifically, an Integer Linear Program (ILP)-based theoretical framework is proposed to identify the optimal selections of backup DCN nodes and data transmission paths, such that the overall data backup cost is minimized. Extensive numerical results are also provided to illustrate the proposed framework for DCN data backup

    Pneumatose kystique intestinale rĂ©vĂ©lĂ©e par une stĂ©nose d’une anastomose gastrojĂ©junale : Ă  propos d’un cas

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    La pneumatose kystique intestinale est la prĂ©sence de bulles gazeuses dans la paroi et les sĂ©reuses du tube digestif. Il s'agit d'une pathologie bĂ©nigne, rare, de diagnostic radiologique et de traitement mĂ©dical. Nous rapportons le cas d'un homme ĂągĂ© de 42ans, opĂ©rĂ© il y a 6ans pour une stĂ©nose du bulbe duodĂ©nal d'origine ulcĂ©reuse, il avait bĂ©nĂ©ficiĂ© d'une gastro-entĂ©ro-anastomose avec bivagotomie tronculaire. Il a Ă©tĂ© hospitalisĂ© pour des vomissements associĂ©s Ă  des Ă©pigastralgies. le patient a bĂ©nĂ©ficiĂ© d'une fibroscopie oeso-gastro-duodĂ©nale qui a trouvĂ© une stase gastrique gĂȘnant toute exploration, ce qui a conduit Ă  la rĂ©alisation d'une tomodensitomĂ©trie abdominale qui a objectivĂ© un Ă©norme estomac de stase en amont d'une stĂ©nose de l'anastomose gastro jĂ©junale, une pneumatose kystique intestinale et un pneumopĂ©ritoine. Le patient a Ă©tĂ© opĂ©rĂ© et l'exploration a trouvĂ© une ascite, un volumineux estomac de stase et des adhĂ©rences entre le grĂȘle et le colon droit, siĂšges de la pneumatose, provoquant un tour de spire (volvulus) de l'ancienne anastomose gastro-jĂ©junale. L'estomac Ă©tait atone. Une gastrectomie des 2/3 emportant l'ancienne anastomose suivie d'une anastomose type Finsterer manuelle a Ă©tĂ© rĂ©alisĂ©e. Les suites post opĂ©ratoires Ă©taient simples. La pneumatose kystique intestinale est une affection bĂ©nigne, de diagnostic radiologique. Le scanner permet d'Ă©tudier la diffusion des gaz dans les sĂ©reuses digestives. Son traitement est habituellement mĂ©dical alors que ses complications peuvent relever d'un traitement chirurgical comme pour notre patient.Key words: Pneumatose kystique intestinale, stĂ©nose, anastomose gastro jĂ©junale, gastrectomie, gastrectomi

    Raman spectroscopy for accurately characterizing biomolecular changes in androgen-independent prostate cancer cells

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    © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim Metastatic prostate cancer resistant to hormonal manipulation is considered the advanced stage of the disease and leads to most cancer-related mortality. With new research focusing on modulating cancer growth, it is essential to understand the biochemical changes in cells that can then be exploited for drug discovery and for improving responsiveness to treatment. Raman spectroscopy has a high chemical specificity and can be used to detect and quantify molecular changes at the cellular level. Collection of large data sets generated from biological samples can be employed to form discriminatory algorithms for detection of subtle and early changes in cancer cells. The present study describes Raman finger printing of normal and metastatic hormone-resistant prostate cancer cells including analyses with principal component analysis and linear discrimination. Amino acid-specific signals were identified, especially loss of arginine band. Androgen-resistant prostate cancer cells presented a higher content of phenylalanine, tyrosine, DNA and Amide III in comparison to PNT2 cells, which possessed greater amounts of L-arginine and had a B conformation of DNA. The analysis utilized in this study could reliably differentiate the 2 cell lines (sensitivity 95%; specificity 88%)

    Performance evaluation of five ELISA kits for detecting anti-SARS-COV-2 IgG antibodies

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    Objectives: To evaluate and compare the performances of five commercial ELISA assays (EDI, AnshLabs, Dia.Pro, NovaTec, and Lionex) for detecting anti-SARS-CoV-2 IgG. / Methods: Seventy negative control samples (collected before the COVID-19 pandemic) and samples from 101 RT-PCR-confirmed SARS-CoV-2 patients (collected at different time points from symptom onset: ≀7, 8–14 and >14 days) were used to compare the sensitivity, specificity, agreement, and positive and negative predictive values of each assay with RT-PCR. A concordance assessment between the five assays was also conducted. Cross-reactivity with other HCoV, non-HCoV respiratory viruses, non-respiratory viruses, and nuclear antigens was investigated. / Results: Lionex showed the highest specificity (98.6%; 95% CI 92.3–99.8), followed by EDI and Dia.Pro (97.1%; 95% CI 90.2–99.2), NovaTec (85.7%; 95% CI 75.7–92.1), then AnshLabs (75.7%; 95% CI 64.5–84.2). All ELISA kits cross-reacted with one anti-MERS IgG-positive sample, except Lionex. The sensitivity was low during the early stages of the disease but improved over time. After 14 days from symptom onset, Lionex and NovaTec showed the highest sensitivity at 87.9% (95% CI 72.7–95.2) and 86.4% (95% CI 78.5–91.7), respectively. The agreement with RT-PCR results based on Cohen's kappa was as follows: Lionex (0.89) > NovaTec (0.70) > Dia.Pro (0.69) > AnshLabs (0.63) > EDI (0.55). / Conclusion: The Lionex and NovaLisa IgG ELISA kits, demonstrated the best overall performance

    Loss of SOCS3 expression in T cells reveals a regulatory role for interleukin-17 in atherosclerosis

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    Atherosclerosis is an inflammatory vascular disease responsible for the first cause of mortality worldwide. Recent studies have clearly highlighted the critical role of the immunoinflammatory balance in the modulation of disease development and progression. However, the immunoregulatory pathways that control atherosclerosis remain largely unknown. We show that loss of suppressor of cytokine signaling (SOCS) 3 in T cells increases both interleukin (IL)-17 and IL-10 production, induces an antiinflammatory macrophage phenotype, and leads to unexpected IL-17–dependent reduction in lesion development and vascular inflammation. In vivo administration of IL-17 reduces endothelial vascular cell adhesion molecule–1 expression and vascular T cell infiltration, and significantly limits atherosclerotic lesion development. In contrast, overexpression of SOCS3 in T cells reduces IL-17 and accelerates atherosclerosis. We also show that in human lesions, increased levels of signal transducer and activator of transcription (STAT) 3 phosphorylation and IL-17 are associated with a stable plaque phenotype. These results identify novel SOCS3-controlled IL-17 regulatory pathways in atherosclerosis and may have important implications for the understanding of the increased susceptibility to vascular inflammation in patients with dominant-negative STAT3 mutations and defective Th17 cell differentiation

    Detecting failure of climate predictions

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    The practical consequences of climate change challenge society to formulate responses that are more suited to achieving long-term objectives, even if those responses have to be made in the face of uncertainty. Such a decision-analytic focus uses the products of climate science as probabilistic predictions about the effects of management policies. Here we present methods to detect when climate predictions are failing to capture the system dynamics. For a single model, we measure goodness of fit based on the empirical distribution function, and define failure when the distribution of observed values significantly diverges from the modelled distribution. For a set of models, the same statistic can be used to provide relative weights for the individual models, and we define failure when there is no linear weighting of the ensemble models that produces a satisfactory match to the observations. Early detection of failure of a set of predictions is important for improving model predictions and the decisions based on them. We show that these methods would have detected a range shift in northern pintail 20 years before it was actually discovered, and are increasingly giving more weight to those climate models that forecast a September ice-free Arctic by 2055
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