Scientific workflows are often composed of compute-intensive simulations and data-intensive analysis and visualization, both equally important for productivity. High-performance computers run the ...compute-intensive phases efficiently, but data-intensive processing is still getting less attention. Dense non-volatile memory integrated into super-computers can help address this problem. In addition to density, it offers significantly finer-grained I/O than disk-based I/O systems. We present a way to exploit the fundamental capabilities of Storage-Class Memories (SCM), such as Flash, by using scalable key-value (KV) I/O methods instead of traditional file I/O calls commonly used in HPC systems. Our objective is to enable higher performance for on-line and near-line storage for analysis and visualization of very high resolution, but correspondingly transient, simulation results. In this paper, we describe 1) the adaptation of a scalable key-value store to a BlueGene/Q system with integrated Flash memory, 2) a novel key-value aggregation module which implements coalesced, function-shipped calls between the clients and the servers, and 3) the refactoring of a scientific workflow to use application-relevant keys for fine-grained data subsets. The resulting implementation is analogous to function-shipping of POSIX I/O calls but shows an order of magnitude increase in read and a factor 2.5x increase in write IOPS performance (11 million read IOPS, 2.5 million write IOPS from 4096 compute nodes) when compared to a classical file system on the same system. It represents an innovative approach for the integration of SCM within an HPC system at scale.
La lecture des contributions de ce numéro de La Révolution Française permet de se faire une idée du corpus croissant d’études sur le sous-continent et sur l’océan Indien qui, dans ces dernières ...années, ont soulevées bien des questions de méthodologie, mais aussi de nombreuses possibilités pour la recherche comparative. Si le colonialisme a été un facteur évident qui a donné unité à l’espace de l’océan Indien et la religion a été un autre domaine important de l’interaction Europe-Asie du sud, le trans-nationalisme, l’universalisme et les régimes de circulation (les réseaux religieux, commerciaux et culturels) dans ce scenario géopolitique suggèrent de nouveaux cadres théoriques pour comprendre et explorer les dynamiques politiques et socio-culturelles des « mondes » de l’océan Indien.
To screen HIV-positive, long-term exposed seronegative and low-risk individuals for the presence of antibodies against regions of HIV-1 gp120 that share some degree of homology with HLA.
Sera were ...obtained from 63 HIV-1-infected subjects 52 Centers for Disease Control and Prevention (CDC) stage 2 and 11 stages 3/4, 32 HIV-exposed uninfected (HEU) subjects and from 24 low-risk HIV-1 seronegative individuals. They were tested by a peptide-based enzyme-linked immunosorbent assay (ELISA) for reactivity against peptides derived from the HIV-1 gp120 C-terminal region that contain regions of MHC sequence/structural similarity. Ten randomly selected sera from each group were also screened for anti-class I antibodies.
Thirty per cent of the long-term HIV-1-exposed seronegative individuals had antibodies against the conserved C-terminal region (C5) of HIV-1 gp120. However, sera from HEU individuals showed no reactivity against other peptides derived from the C2 region of gp120, also an HLA homologous region. Anti-C terminal gp120 antibodies were mainly of IgM subclass, although IgG-specific antibodies were also present. In addition, 70% of HEU individuals had antibodies to HLA class I molecules compared with 15% of HIV-positive patients (restricted to only those HIV-positive patients with anti C-terminal antibodies).
Our results suggest that antibody responses against the C-terminal region of HIV gp120 and HLA class I may represent markers of apparent natural protection against HIV-1 infection.
The precise mechanism of the pathogenesis of alcoholic hepatitis is unknown, but immune involvement may perpetuate and exacerbate the process. Heat-shock proteins, normally protective, may be ...immunogenic and have been shown to induce antibody formation in some inflammatory conditions. Alcohol, cellular hypoxia and tumor necrosis factor, all involved in alcoholic hepatitis, are potent inducers of heat-shock protein. In this study, we sought 60-kD heat-shock protein in liver tissue with a murine monoclonal antibody and measured circulating antibody to 60-kD heat-shock protein on ELISA. Fourteen of 20 livers from patients with acute alcoholic hepatitis expressed 60-kD heat-shock protein in hepatocyte cytoplasm in a diffuse pattern with superimposed clusters; other cell types were occasionally positive. Twelve of these patients had high-titer IgA 60-kD heat-shock protein antibody in serum. In contrast, 60-kD heat-shock protein was identified in only 2 of the 10 patients with alcoholic cirrhosis without hepatitis (p = 0.013). These two patients had severe liver disease, and one patient in this group was seropositive for IgA 60-kD heat-shock protein antibody. Eight alcoholic patients with fatty liver alone were negative for antigen, and all but one were negative for antibody. The 10 patients without liver damage were negative for antigen and antibody. The findings that 60-kD heat-shock protein is present in liver tissue of patients with acute alcoholic liver damage and that circulating IgA 60-kD heat-shock protein antibody levels are increased may point to one pathogenetic mechanism underlying development and progression of liver damage in alcoholic hepatitis.
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BFBNIB, FZAB, GIS, IJS, KILJ, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The existence of HIV positive individuals who do not appear to progress to disease, or do so only very slowly (LTNPs), strongly suggest that factors other than virus pathogenicity determine disease. ...The occurence of HIV infected chimpanzees that remain disease free and other African SIV infected primates where disease is apparently species specific underscores the importance of host factors
1,2. We have examined the immune response of LTNP patients using a variety of techniques including intracellular cytokine FACscan, anchor PCR analysis of the T cell receptor and HLA typing of class II genes by DNA sequencing. Our results to date confirm that the development of disease is consistent with activation of a susceptible immune system, and that this could be due to the fact that HLA-like sequences of HIV may ‘allo’ activate the host immune response. In order to test this hypothesis further we have examined whether gp120 itself can bind and present specific peptides which may be capable of eliciting ‘allo’ activation responses in particular hosts.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
A 26-year-old female was on continuous ambulatory peritoneal dialysis (CAPD) because of diabetic end-stage renal failure. She developed an acute peritonitis that relapsed repeatedly despite ...appropriate antibiotic treatment. Investigations showed the presence of a splenic abscess, and splenectomy and peritoneal cannula removal were required. The patient died of myocardial infarction two weeks postoperatively. This is the first recorded case of peritonitis secondary to splenic abscess in a CAPD patient. Autopsy findings suggest that the abscess developed from infection of a splenic infarct.
