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1.
Cloud computing services have recently become a ubiquitous service delivery model, covering a wide range of applications from personal file sharing to being an enterprise data warehouse. Building green data center networks providing cloud computing services is an emerging trend in the Information and Communication Technology (ICT) industry, because of Global Warming and the potential GHG emissions resulting from cloud services. As one of the first worldwide initiatives provisioning ICT services entirely based on renewable energy such as solar, wind and hydroelectricity across Canada and around the world, the GreenStar Network (GSN) was developed to dynamically transport user services to be processed in data centers built in proximity to green energy sources, reducing Greenhouse Gas (GHG) emissions of ICT equipments. Regarding the current approach, which focuses mainly in reducing energy consumption at the micro-level through energy efficiency improvements, the overall energy consumption will eventually increase due to the growing demand from new services and users, resulting in an increase in GHG emissions. Based on the cooperation between Mantychore FP7 and the GSN, our approach is, therefore, much broader and more appropriate because it focuses on GHG emission reductions at the macro-level. This article presents some outcomes of our implementation of such a network model, which spans multiple green nodes in Canada, Europe and the USA. The network provides cloud computing services based on dynamic provision of network slices through relocation of virtual data centers.  相似文献   
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The male-produced aggregation pheromones of Tetropium fuscum (F.) and T. cinnamopterum Kirby were identified as (2S,5E)-6,10-dimethyl-5,9-undecadienol by chemical analysis, synthesis, electronantennography, and field trapping; the compound is here renamed “fuscumol”. The effect of fuscumol chirality, alone or with host volatiles, and fuscumol release rate on Tetropium spp. was tested in field-trapping experiments in Nova Scotia and Poland. Both (S)-fuscumol and racemic fuscumol synergized trap catches of male and female T. fuscum, T. cinnamopterum, and T. castaneum (L.) when combined with a blend of host monoterpenes and ethanol. Without added host volatiles, fuscumol was either unattractive (in Nova Scotia) or only slightly so (in Poland). (R)-Fuscumol, alone or in combination with host volatiles, did not elicit increases in trap capture of any Tetropium species, relative to the controls. Fuscumol synergized attraction of both sexes to host volatiles, thus indicating it acts as an aggregation pheromone. Sex ratio was often female-biased in traps baited with fuscumol plus host volatiles, and was either unbiased or male-biased in traps with host volatiles alone. In traps with host volatiles and racemic fuscumol, mean catches of Tetropium species were unaffected by fuscumol release rates ranging from 1 to 32 mg/d. The attraction of three different Tetropium species to the combination of (S)-fuscumol and host volatiles suggests that cross-attraction may occur where these species are sympatric, and that reproductive isolation possibly occurs via differences in close-range cues. These results have practical applications for survey and monitoring of T. fuscum, a European species established in Nova Scotia since at least 1980, and for early detection of T. castaneum, a European species not presently established in North America.  相似文献   
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Erroneous beliefs have been identified as key variables related to the development and maintenance of excessive worry. For example, people presenting a high level of worry often believe that worrying helps them to prevent the occurrence of future negative events or translates a positive characteristic of their personality. They thus develop excessive and uncontrollable worries in order to maintain the perceived advantages. The factors related to the development and the maintenance of erroneous beliefs about worry are however unknown. The aim of this study was to verify the relationship between erroneous beliefs and personal variables (i.e., gender, worry themes, and predominant types of worries) in a sample of 544 participants. Analyses showed that beliefs differed significantly according to the gender, but not according to the predominant types of worries. School concerns were significantly associated with the belief that worry helps to motivate. This study brings preliminary useful information to better understand the presence of erroneous beliefs about worries and suggests conducting further researches using other personal variables and clinical samples. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Macrophages exudating into inflammatory sites (thioglycollate-elicited macrophages, TGM) have a diminished ability to synthesize prostaglandins (PG) as compared with resident peritoneal macrophages (RM). Constitutive expression of cyclooxygenase-1 (COX-1) was lower in TGM than in RM but the releasability of arachidonic acid was not significantly different. Thus, the differences in expression of COX-1 were primarily responsible for the abilities of TGM and RM to synthesize PGE2 upon calcium ionophore (CaI) stimulation. COX-1 expression in RM and TGM was also correlated with their ability to synthesize PGE2 from exogenously added arachidonic acid. When exposed to lipopolysaccharide (LPS), the induction of COX-2 and the enhancement of PGE2 synthesis upon CaI were much lower in TGM as compared with RM the releasability of arachidonic acid upon CaI stimulation was relatively unchanged in RM but was reduced in TGM Thus, in TGM as compared with RM, a lower level of COX-1 expression and a lower level of COX-2 induction, and the reduction of arachidonate releasability by LPS exposure, are mainly responsible for lower PGE2 synthetic ability upon CaI stimulation. However, the different COX-2 induction by LPS in RM and TGM was not reflected in their increase in the ability to synthesize PGE2 from exogenously added arachidonic acid.  相似文献   
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One-hundred and five Candida albicans isolates from various anatomic sites of 28 patients, obtained at the onset of two consecutive episodes of well-documented recurrent vulvovaginitis, were typed by methods relying on physiologic or genomic markers. The isolates represented a wide variety of types, and neither a single biotype nor genotype was associated with recurrent vaginitis or a particular body site. Patients generally carried similar strains at various anatomic sites that persisted over time. Genomic methods indicated an 86% rate of relapse, which suggested that most recurrent vaginal infections are of endogenous origin. A similar evaluation with biotyping methods was inconclusive because of a lack of reproducibility, resulting from clonal variation or switching, and difficulties in establishing the number of phenotypic tests necessary to distinguish between identical and different strains. Therefore, Southern hybridization was considered the ideal reference method to study the epidemiology of C. albicans infections.  相似文献   
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We report a new technique for fabricating electrodes for electrochemical applications with lateral dimensions in the range 15-200 nm and a reproducible, well-defined geometry. This technique allows determining the electrode size by electron microscopy prior to electrochemical measurements and without contamination of the metal electrode. We measured the diffusion-limited current with stepped-current voltammetry and showed that its dependence on electrode size can be quantitatively understood if the known geometry of the electrodes is explicitly taken into account.  相似文献   
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We report on the fabrication and characterization of gold nanoelectrodes with carefully controlled nanometer dimensions in a matrix of insulating silicon nitride. A focused electron beam was employed to drill nanopores in a thin silicon nitride membrane. The size and shape of the nanopores were studied with high-resolution transmission electron microscopy and electron-energy-loss two-dimensional maps. The pores were subsequently filled with gold, yielding conically shaped nanoelectrodes. The nanoelectrodes were examined by atomic and electrostatic force microscopy. Their applicability in electrochemistry was demonstrated by steady-state cyclic voltammetry. Pores with a radii down to 0.4 nm and electrodes with radii down to 2 nm are demonstrated.  相似文献   
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The main objective of this article is to present the results gathered during the commissioning of a new ice-free cup anemometer developed at Université Laval. These tests took place at the Wind Energy Institute of Canada (WEICan) between January 2011 and April 2011, whereby icing events occurred and through the observations in this paper will show the need for ice-free anemometers in the wind industry in cold climates. Unbiased wind measurements cannot be obtained without ice-free anemometers. At such sites, the use of unheated wind speed sensors during the resource assessment phase leads to higher uncertainty of the wind speed. The use of properly heated anemometers can reduce wind speed measurement uncertainty, thus reducing financial uncertainty. A crude estimation of the financial losses based on the number of icing hours and the number of installed MW is also proposed. Caution should be exerted when choosing and installing ice-free instruments. Under specific conditions, improperly heated anemometers can lead to less accurate wind measurements than unheated anemometers. Wind turbines safe operation could be jeopardized with the use of improperly heated anemometers.  相似文献   
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