In the next decade, a growing number of scientific and industrial applications will require power-efficient systems providing unprecedented computation, memory, and communication resources. A ...promising paradigm foresees the use of heterogeneous many-tile architectures. The resulting computing systems are complex: they must be protected against several sources of faults and critical events, and application programmers must be provided with programming paradigms, software environments and debugging tools adequate to manage such complexity. The EURETILE (European Reference Tiled Architecture Experiment) consortium conceived, designed, and implemented: 1- an innovative many-tile, many-process dynamic fault-tolerant programming paradigm and software environment, grounded onto a lightweight operating system generated by an automated software synthesis mechanism that takes into account the architecture and application specificities; 2- a many-tile heterogeneous hardware system, equipped with a high-bandwidth, low-latency, point-to-point 3D-toroidal interconnect. The inter-tile interconnect processor is equipped with an experimental mechanism for systemic fault-awareness; 3- a full-system simulation environment, supported by innovative parallel technologies and equipped with debugging facilities. We also designed and coded a set of application benchmarks representative of requirements of future HPC and Embedded Systems, including: 4- a set of dynamic multimedia applications and 5- a large scale simulator of neural activity and synaptic plasticity. The application benchmarks, compiled through the EURETILE software tool-chain, have been efficiently executed on both the many-tile hardware platform and on the software simulator, up to a complexity of a few hundreds of software processes and hardware cores.
We investigated in IMR90 cells the effects of
N-formyl-Met-Leu-Phe (
N-fMLP) and WKYMVm (W peptide) on activation of the NADPH oxidase-like enzyme. In serum-deprived human fibroblasts, exposure to ...100 μM
N-fMLP or 10 μM peptide W for 1 min induced both p47
phox translocation and NADPH-dependent superoxide generation. These effects were in large part mediated by prevention of the rapid activation of extracellular signal-regulated kinases (ERKs) by preincubation with the MEK1 inhibitor PD098059. Furthermore, responses to
N-fMLP or W peptide were inhibited by pertussis toxin, suggesting the involvement of a seven-transmembrane G protein-coupled receptor(s) for peptides. RT-PCR experiments demonstrated the expression in these cells of the low-affinity receptor FPRL1, but not the high-affinity receptor FPR. Incubation with radiolabeled WKYMVm, which had a higher efficiency on FPRL1, revealed that human fibroblasts express binding sites for
125I-WKYMVm that are specifically displaced by increasing concentrations of unlabeled ligand. Analysis of the binding data predicted a
K
d
of 155.99 nM and a receptor density of about 16,200 molecules/cell. HEK293 cells, which express a NADPH oxidase-like enzyme but not formyl peptide receptors, transiently transfected with FPRL1 cDNA produced superoxide on stimulation with
N-fMLP or W peptide, demonstrating that this receptor is biologically functional.
Summary form only given. We present APENet, a new high speed, low latency, 3-dimensional interconnect architecture optimized for PC clusters running LQCD-like numerical applications. The hardware ...implementation is based on a single PCI-X 133MHz network interface card hosting six independent bidirectional channels with a peak bandwidth of 676 MB/s each direction and measured latency less than 10 /spl mu/s. The internal packet switching capabilities of the network card allows up to three couple of links simultaneously active. The current software environment, based on Linux, is made of a low-level library and a high-level application library. An MPI implementation and a network device driver are being actively developed.
Liver disease may be found in patients with primary immunodeficiency syndromes because of the high risk of infection with hepatotropic viruses related to the treatment with blood derivatives. The ...prevalence of liver disease in these patients and its etiology, however, is still not completely understood. We have evaluated the prevalence and the etiology of liver disease in children with different forms of primary immunodeficiencies. Thirty patients included in the study underwent molecular studies to detect common hepatotropic viruses, including hepatitis C and G viruses. Liver involvement was found in 11 of 30 (36.6%) patients. All patients with liver disease had deficiencies of specific immunity, with a prevalence in this subgroup of 47.8%. Liver disease was more severe in patients with T and B cell combined immune disorders than in those with a selective T cell immunodeficiency. Moreover, the severity of the disease correlated with an overall more rapid fatal outcome. A viral etiology was found in only six of these patients, whereas in the remaining five patients, no cause of liver injury was identified. In the virally infected patients, hepatitis C virus was the most common viral agent. In patients with immunodeficiencies, there is a high prevalence of liver disease not fully explained on the basis of the common viral infections.
Reactive oxygen species have been implicated as possible second messengers in mitogenic signal transduction. We demonstrate that in normal fibroblasts the treatment with the two inhibitors of ...phagocytic NADH/NADPH oxidase prevents tyrosine phosphorylation of platelet-derived growth factor receptor upon the exposure of serum-deprived cells to growth factors. Furthermore, the inhibition of NADH/NADPH oxidase abolishes ERKs activation and p21waf1 accumulation that occurs when cells are exposed to growth factors. Finally, NADH/NADPH inhibitors prevent the p66Shc Ser-phosphorylation induced by serum and by phorbol 12-myristate-13-acetate, which suggests that the direct target(s) of reactive oxygen species is(are) located upstream from the machinery connecting growth factor receptors to Ras.
We have characterized the promoter of the human gene coding for the apoferritin L subunit. Transient transfections of 5′ and 3′ deletion mutants indicate that the efficiency of the L promoter depends ...on both negative and positive cis-elements, located upstream and downstream of the transcription start point. DNaseI footprinting analysis of this DNA region revealed the presence of five protected segments. The most upstream one (element 1) corresponds to the negative cis-element and is recognized by factor(s) sharing a GC-sequence specificity. Three positive elements are in the region upstream of the start of transcription; a fifth positive cis-element (element 5) is localized in the first exon of the L gene.
PDF
