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André Girard Pierre Dominique Lansard Bernard Liau Anne Marie Mongeon Jean Luc Thibault 《电信纪事》1991,46(5-6):335-350
Classical hierarchical routing in telephone networks is extended to a wider class called out-of-chain routing in such a way that some useful properties of hierarchical routing are retained. This new routing pattern offers more potential paths than the fixed hierarchical one and can be introduced as a dynamic routing where the fixed alternate sequences change at some predetermined instants during the day. The effect of this new routing pattern on the network performances is examined. The main topic of this paper is to present heuristic methods used to optimise such routings in large networks. We show on artificial networks that the throughput of a given network can be significantly improved by suitable routing choices. We demonstrate that the integration of routing changes within a multihour dimensioning process is possible but the lack of realistic data does not permit at this time to quantify the value of routing optimization on real networks. 相似文献
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De Fruyt Filip; Van Leeuwen Karla; Bagby R. Michael; Rolland Jean-Pierre; Rouillon Frédéric 《Canadian Metallurgical Quarterly》2006,18(1):71
Structural, mean- and individual-level, differential, and ipsative personality continuity were examined in 599 patients treated for major depression assigned to 1 of 6 forms of a 6-month pharmaco-psychotherapy program. Covariation among traits from the Five Factor model remained invariant across treatment, and patients described themselves as slightly more extraverted, open to experience, agreeable and conscientious, and substantially more emotional stable after treatment. Trait changes were only to a small extent explained by changes in depression severity. There was evidence for differential, individual-level, and ipsative stability, with stable personality profiles in terms of shape and to a lesser extent in terms of scatter and elevation. Traits remain relatively stable, except for emotional stability, despite the depressive state and the psychopharmacological interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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We study the behavior of disk assemblies with a variable disorder distribution. The packing is first consolidated and then continuously tilted very slowly. The amount of displaced disks for each tilted angle is recorded. Large displacements of the disks can occur due to some local or global mechanical instabilities. The definition of neighboring disks is based on radical (extension of Voronoï) tessellation rules to decompose, in a unique and perfectly defined manner, the two-dimensional space for polydisperse disks. In this way, by comparing the characteristics of stability for one disk to the neighboring ones for local ordered cluster, we can predict the global amount of displaced disks. Some tilting cycles have been performed to check the correlation between the instability of the packing structure (collective displacements) with micro and macro order parameters. 相似文献
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Impact of apolipoprotein E polymorphism on lipoproteins and risk of myocardial infarction. The ECTIM Study 总被引:2,自引:0,他引:2
G Luc JM Bard D Arveiler A Evans JP Cambou A Bingham P Amouyel P Schaffer JB Ruidavets F Cambien 《Canadian Metallurgical Quarterly》1994,14(9):1412-1419
Human apolipoprotein (apo) E, a polymorphic protein with three common alleles, epsilon 2, epsilon 3, and epsilon 4, plays an important role in lipoprotein metabolism. This article describes the association of this polymorphism with lipids, apolipoproteins, and lipoproteins with a particular regard to lipoprotein particles, as defined by their apolipoprotein content, as well as the risk of myocardial infarction in a multicenter population-based case-control study (ECTIM study). In the ECTIM study, 574 male patients aged 25 to 64 were examined 3 to 9 months after myocardial infarction in four regions participating in the World Health Organization MONICA project: Belfast (Northern Ireland) and Lille, Strasbourg, and Toulouse (France). Control subjects (n = 722) were randomly selected from the regional populations. The distribution of apoE phenotypes was significantly different across the four control samples (P = .04), with a higher frequency of the epsilon 4 allele in Belfast (14.3%) than in Toulouse (8.2%). The association of apoE polymorphism with biological measurements was studied in the control groups (n = 640) after men with coronary heart disease or those taking hypolipidemic drugs were omitted, with the apoE3/3 phenotype as a reference after adjustment for concomitant factors. Individuals carrying the epsilon 2 allele had lower levels of plasma cholesterol, low-density lipoprotein cholesterol (LDL-C), and apoB and higher levels of triglycerides, very-low-density lipoprotein cholesterol (VLDL-C), apoC-III, apoE, lipoprotein (Lp) C-III:B, and Lp E:B. However, the effect of the epsilon 2 allele on triglyceride, VLDL-C, apoE, and Lp E:B parameters was heterogeneous across the populations.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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P Cappelaere B Hecquet F Rolland L Meeus C Domenge I Krakowski C De Gislain J Chauvergne F Dufour-Esquerré P Carde 《Canadian Metallurgical Quarterly》1995,82(9):732-737
Eighty-four patients with locally advanced, non metastatic squamous cell carcinoma of head and neck or esophagus, were included in a multicentric double-blind randomized trial, comparing goralatide (12.5 or 62.5 micrograms/kg/day, d1-d4) to placebo, associated with carboplatin (400 mg/m2, d1) and 5-fluorouracile (1 g/m2/d continuous IV over 96 hours). Haematological toxicity was analysed on 221 cycles of chemotherapy. All but one patient were evaluable because of early death without haematological toxicity. No significant difference was observed for mean nadir of leukocytes, granulocytes, platelets counts and hemoglobin level. Duration of haematological toxicity was no significantly different for the two groups of patients. Anemia and lymphopenia were more frequent in the goralatide treated patients. Clinical and biological tolerability of goralatide was excellent. 相似文献
19.
Neuronal activation was examined by fos immunohistochemistry in ring doves (Streptopelia risoria) reunited with their young after overnight separation. In an initial study, squab-exposed parents showed more fos immunoreactivity (ir) in the preoptic area (POA) and lateral hypothalamus (LH) than squab-deprived parents. In a 2nd study, parents allowed free access to young and those separated from young by a wire mesh partition showed more fos-ir in the POA, LH, and lateral septum than box-exposed controls. Contact with young also increased fos-ir in the medial preoptic nucleus and bed nucleus of the stria terminalis, but noncontact exposure did not. Conversely, nontactile squab exposure stimulated more fos-ir in the POA than did free access to young, which suggests POA involvement in appetitive aspects of parenting. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Sanja Ramljak Matthias Schmitz Cendrine Repond Inga Zerr Luc Pellerin 《International journal of molecular sciences》2021,22(4)
The effect of a cellular prion protein (PrPc) deficiency on neuroenergetics was primarily analyzed via surveying the expression of genes specifically involved in lactate/pyruvate metabolism, such as monocarboxylate transporters (MCT1, MCT2, MCT4). The aim of the present study was to elucidate a potential involvement of PrPc in the regulation of energy metabolism in different brain regions. By using quantitative real-time polymerase chain reaction (qRT-PCR), we observed a marked reduction in MCT1 mRNA expression in the cortex of symptomatic Zürich I Prnp−/− mice, as compared to their wild-type (WT) counterparts. MCT1 downregulation in the cortex was accompanied with significantly decreased expression of the MCT1 functional interplayer, the Na+/K+ ATPase α2 subunit. Conversely, the MCT1 mRNA level was significantly raised in the cerebellum of Prnp−/− vs. WT control group, without a substantial change in the Na+/K+ ATPase α2 subunit expression. To validate the observed mRNA findings, we confirmed the observed change in MCT1 mRNA expression level in the cortex at the protein level. MCT4, highly expressed in tissues that rely on glycolysis as an energy source, exhibited a significant reduction in the hippocampus of Prnp−/− vs. WT mice. The present study demonstrates that a lack of PrPc leads to altered MCT1 and MCT4 mRNA/protein expression in different brain regions of Prnp−/− vs. WT mice. Our findings provide evidence that PrPc might affect the monocarboxylate intercellular transport, which needs to be confirmed in further studies. 相似文献