On Dependent Data Fetching in Cloud Environment

This work was motivated by the study of the file fetching process in a cloud system, in particular by the recent progress in the model of transparent computing. A transparent computing system may have many clients, each requesting a significant set of files from the server, including user data and many commonly used softwares (operating systems and apps). These files may have inherent dependence relations so should be received by the clients in a specific topological order. On the other hand, since many of these files are commonly used softwares, many clients may request copies of the same files. This proposes an interesting problem on the server side of how this kind of requests should be handled efficiently to improve the performance of the system. In particular, we are interested in the processes that significantly reduce the disk IO operations in the server, which are in general very time-consuming. We propose a formal model for this problem and study its validity and correctness. Heuristic algorithms for the problem are proposed and studied. Simulation results are presented to compare the proposed heuristics and algorithms based on known techniques in scheduling literature. 7% - 20% of the total disk IO can be reduced via the optimizations proposed in this work

Building a robust word-level wakeword verification network

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Epithelial Heat Shock Proteins Mediate the Protective Effects of Limosilactobacillus reuteri in Dextran Sulfate Sodium-Induced Colitis

Defects in gut barrier function are implicated in gastrointestinal (GI) disorders like inflammatory bowel disease (IBD), as well as in systemic inflammation. With the increasing incidence of IBD worldwide, more attention should be paid to dietary interventions and therapeutics with the potential to boost the natural defense mechanisms of gut epithelial cells. The current study aimed to investigate the protective effects of Limosilactobacillus reuteri ATCC PTA 4659 in a colitis mouse model and delineate the mechanisms behind it. Wild-type mice were allocated to the control group; or given 3% dextran sulfate sodium (DSS) in drinking water for 7 days to induce colitis; or administered L. reuteri for 7 days as pretreatment; or for 14 days starting 7 days before subjecting to the DSS. Peroral treatment with L. reuteri improved colitis severity clinically and morphologically and reduced the colonic levels of Tumor necrosis factor-alpha (TNF-alpha) (Tnf), Interleukin 1-beta (Il1 beta), and nterferon-gamma (Ifng), the crucial pro-inflammatory cytokines in colitis onset. It also prevented the CD11b(+)Ly6G(+) neutrophil recruitment and the skewed immune responses in mesenteric lymph nodes (MLNs) of CD11b(+)CD11c(+) dendritic cell (DC) expansion and Foxp3(+)CD4(+) T-cell reduction. Using 16S rRNA gene amplicon sequencing and RT-qPCR, we demonstrated a colitis-driven bacterial translocation to MLNs and gut microbiota dysbiosis that were in part counterbalanced by L. reuteri treatment. Moreover, the expression of barrier-preserving tight junction (TJ) proteins and cytoprotective heat shock protein (HSP) 70 and HSP25 was reduced by colitis but boosted by L. reuteri treatment. A shift in expression pattern was also observed with HSP70 in response to the pretreatment and with HSP25 in response to L. reuteri-DSS. In addition, the changes of HSPs were found to be correlated to bacterial load and epithelial cell proliferation. In conclusion, our results demonstrate that the human-derived L. reuteri strain 4659 confers protection in experimental colitis in young mice, while intestinal HSPs may mediate the probiotic effects by providing a supportive protein-protein network for the epithelium in health and colitis