281 research outputs found

    Automatic generation of scheduling and communication code in real-time parallel programs

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    Inter-process communication and scheduling are notorious problem areas in the design of real-time systems. Using CASE tools, the system design phase will in general result in a system description in the form of parallel processes. Manual allocation of these processes to processors may result in error prone and/or slow communication code. Scheduling of the processes, necessary to meet timing constraints, is also a tedious task that takes many iterations. The described design tools result in code that is comparable in quality and performance with expert manual realization. Many network layers have been implemented to relieve the user from the low-level programming of communication software. However, the increase in user-friendliness is usually paid with performance degradation. The proposed approach combines user-friendliness with high performance by generating communication software that is tailor-made for the application. A similar approach is followed with the scheduling software. Schedulers in the form of a built-in a kernel are available all the time and cause overhead all the time. The proposed preprocessor tool generates scheduling software after analyzing the timing requirements of the particular application. This results in simple code for simple timing requirements and more complicated code for complex timing requirements. The tools have been implemented in Occam for use on a transputer. However, the results are valid for any distributed memory machine

    Highly syntenic and yet divergent: a tale of two Theilerias

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    The published genomic sequences of the two major host-transforming Theileria species of cattle represent a rich resource of information that has allowed novel bioinformatic and experimental studies into these important apicomplexan parasites. Since their publication in 2005, the genomes of T. annulata and T. parva have been utilised for a diverse range of applications, ranging from candidate antigen discovery to the identification of genetic markers for population analysis. This has led to advancements in the quest for a sub-unit vaccine, while providing a greater understanding of variation among parasite populations in the field. The unique ability of these Theileria species to induce host cell transformation is the subject of considerable scientific interest and the availability of full genomic sequences has provided new insights into this area of research. This article reviews the data underlying published comparative analyses, focussing on the general features of gene expression, the major Tpr/Tar multi-copy gene family and a re-examination of the predicted macroschizont secretome. Codon usage between the Theileria species is reviewed in detail, as this underpins ongoing comparative studies investigating selection at the intra- and inter-species level. The TashAT/TpshAT family of genes, conserved between T. annulata and T. parva, encodes products targeted to the host nucleus and has been implicated in contributing to the transformed bovine phenotype. Species-specific expansion and diversification at this critical locus is discussed with reference to the availability, in the near future, of genomic datasets which are based on non-transforming Theileria species

    Demonstration of vincristine resistance in primary intestinal neoplasms in the rat by the 'post-metaphase index'.

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    A method is described enabling the direct measurement of vincristine resistance in intact tissues in vivo by morphological study. Using the metaphase arresting properties of the drug, counts were made of escaping anaphase and telophase mitotic figures at a range of doses. The proportion of post-metaphase mitotic figures is called the post-metaphase index (PMI). In 95 primary intestinal tumours induced by dimethylhydrazine (DMH) in rats, an increase in resistance to vincristine was shown over normal mucosa (P less than 0.001). The data were analysed by computer modelling and a linear relationship is demonstrated between the logit of the post-metaphase index, and log dose of vincristine. To achieve a PMI of 1% the fitted lines show an enhanced vincristine dose requirement over normal mucosa of 6 times in colonic tumours, and 8 times in small intestinal tumours. Non-neoplastic mucosa from the DMH-treated animals requires an enhanced dose of vincristine of 1.5 times, compared with normal mucosa, to achieve a PMI of 1%. Given current interest in the mechanism of vincristine resistance in cell lines this new approach provides a technique for assessing the resistance of solid tumours, both in vivo and in vitro, and for subsequent experimental manipulation

    Verapamil sensitizes normal and neoplastic rodent intestinal tissues to the stathmokinetic effect of vincristine in vivo.

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    A morphological method has been developed allowing measurement of the effect on intestinal epithelia of vincristine. In routinely prepared tissue sections the proportion of mitotic events progressing beyond metaphase is counted by microscopy. When estimated over a range of doses of vincristine this post-metaphase index (PMI) can be used to compare the sensitivity of differing intact tissues. Intestinal tumours were induced in rats by chemical carcinogenesis. Administration of vincristine in the presence or absence of verapamil was performed in these tumour-bearing animals. Sections were prepared from colonic and small-bowel tumours and from normal mucosa. The results show that verapamil increases the sensitivity of the tissues studied to vincristine. A dose dependent effect of verapamil on vincristine sensitisation was demonstrated in colonic tissues. These findings indicate a shared pharmacological property between the resistance of primary tumour tissue and the multidrug-resistance phenotype

    Role of Topoisomerase IIβ in DNA Damage Response following IR and Etoposide

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    The role of topoisomerase IIβ was investigated in cell lines exposed to two DNA damaging agents, ionising radiation (IR) or etoposide, a drug which acts on topoisomerase II. The appearance and resolution of γH2AX foci in murine embryonic fibroblast cell lines, wild type and null for DNA topoisomerase IIβ, was measured after exposure to ionising radiation (IR) or etoposide. Topoisomerase II-DNA adduct levels were also measured. IR rapidly triggered phosphorylation of histone H2AX, less phosphorylation was seen in TOP2β−/− cells, but the difference was not statistically significant. IR did not produce topoisomerase II-DNA adducts above control levels. Etoposide triggered the formation of topoisomerase II-DNA adducts and the phosphorylation of histone H2AX, the γH2AX foci appeared more slowly with etoposide than with IR. Topoisomerase II-DNA complexes in WT cells but not TOP2β−/− cells increased significantly at 24 hours with the proteasome inhibitor MG132, suggesting topoisomerase IIβ adducts are removed by the proteasome

    Special session: Hot topics: Statistical test methods

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    International audienceThe process of testing Integrated Circuits involves a huge amount of data: electrical circuit measurements, information from wafer process monitors, spatial location of the dies, wafer lot numbers, etc. In addition, the relationships between faults, process variations and circuit performance are likely to be very complex and non-linear. Test (and its extension to diagnosis) should be considered as a challenging highly dimensional multivariate problem.Advanced statistical data processing offers a powerful set of tools, borrowed from the fields of data mining, machine learning or artificial intelligence, to get the most out of this data. Indeed, these mathematical tools have opened a number of novel and interesting research lines within the field of IC testing.In this special session, prominent researchers in this field will share their views on this topic and present some of their last findings. The first talk will discuss the interest of likelihood prevalence in random fault simulation. The second talk will show how statistical data analysis can help diagnosing test efficiency. The third talk will deal with the reliability of Alternate Test of AMS-RF circuits. The fourth and last talk will address the idea of mining the test data for improving design manufacturing and even test itself
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