46 research outputs found

    The Evolution of OSI Network Management by Integrated the Expert Knowledge

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    The management of modern telecommunications networks must satisfy ever-increasing operational demands. Operation and quality service requirements imposed by the users are also an important aspect to consider. In this paper we have carried out a study for the improvement of intelligent administration techniques in telecommunications networks. This task is achieved by integrating knowledge base of expert system within the management information used to manage a network. For this purpose, an extension of OSI management framework specifications language has been added and investigated in this study. A new property named RULE has also been added, which gathers important aspects of the facts and the knowledge base of the embedded expert system. Networks can be managed easily by using this proposed integration

    Hard Metal Production by ERS: Processing Parameter Roles in Final Properties

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    Cemented carbide is a hard composite material, used widely in a variety of industries. The value of the global tungsten carbide market is expected to grow by 4.4% (compound annual growth rate) from 2017 to 2022. One of the main markets is in metal cutting and wear parts, where small pieces (or inserts), a few grams in weight, are used. Field-assisted sintering technique (FAST) technologies allow for the production of small blanks in a single step from powder, which are near final dimensions. Production cycles are very short. In this paper, one of the FAST processes, the ERS technology, is applied to obtain WC10Co parts. A review of the process variable effects on the final properties of the parts is accomplished. Final properties of a range of conventionally produced inserts are obtained, using 100 MPa compacting pressure, 80 MA/m2 of current density, and processing times of around 800 ms.This research was funded by EU, grant number FoF.NMP.2013-10 608729 (7th Framework Programme) EFFIPRO

    Design and Test of a Miniature Hydrogen Production Integrated Reactor

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    A detailed study of the experimental issues involved in the design and operation of a methanol steam microreformer is presented in this paper. Micromachining technology was utilized to fabricate a metallic microchannel block coupling the exothermic and endothermic process. The microchannel block was coated with a Pd/ZnO catalyst in the reforming channels and with Pd/Al2O3 in the combustion channels by washcoating. An experimental system had been designed and fine-tuned allowing estimation of the heat losses of the system and to compensate for them by means of electric heating cartridges. In this way, the heat necessary for the reforming reaction is provided by methanol combustion, thanks to the temperature and flow cascade controller we developed. Thus, the coupling of both reactions in a block of microchannels without the interference caused by significant heat loss due to the small size of the laboratory microreactor could be studied. Runs of this microreformer device were carried out, varying the deposited catalyst amount, methanol steam reforming temperature and space velocity. When the reforming reaction was compensated by the combustion reaction and the heat losses by the electric heating, an almost isothermal behavior of the microchannel reactor was observed. In the less favorable case, with a 460 mg catalyst load, ΔTMSR was about 8 K and ΔTCOMB was about 16 K. This confirmed good coupling of the methanol steam reforming and the methanol combustion.This research was funded by MICINN/FEDER grant numbers RTI2018-096294-B-C32 and CTQ2015-73901-JIN and by the Basque Government grant number IT1069-16

    Structuring Cu/ZnO/Al2O3 catalyst for methanol synthesis: Slurry additive effect in the washcoating method

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    The best slurry formulation to prepare a structured catalyst for methanol synthesis reaction by washcoating method was investigated. The effect of different inorganic oxide colloids in the slurry preparation of Cu/ZnO/Al2O3 catalyst was studied: colloidal ZnO, SiO2, and Al2O3. The addition of all these colloids showed an improvement in adherence obtained on Fecralloy® monoliths, but Al2O3 exhibited the best performance. Adherence >80% was obtained with a lower amount of Al2O3 than with the other colloids. Nevertheless, the addition of these additives changes the catalytic properties of the parent catalyst. Adding a high amount of colloids decreases the copper metallic surface area which is the active phase of the methanol synthesis reaction. Moreover, the addition of Al2O3 gave rise to the dehydration of methanol to dimethyl ether (DME) due to the high acidity that Al2O3 presents. Something similar happens but to a less extent with SiO2, which present weak acidity. In contrast, the basic character of ZnO neutralizes the parent catalyst's low acidity reducing the selectivity to DME. Finally, the slurry formulation containing 10% Al2O3 exhibited the best methanol yield. Hence, a methanol synthesis structured catalyst was successfully prepared with similar activity to the powder catalyst.The authors acknowledge the Basque Government (IT1069-16), the Spanish MINECO/FEDER (RTI2018-096294-B-C32 and CTQ2015-73901-JIN) and The University of the Basque Country (GIU21/033) for the financial support. I. Pérez-Miqueo also acknowledges the Basque Government for the PhD scholarship (PRE_2014_1_141)

    Complementing the Pleistocene biogeography of European amphibians: Testimony from a southern Atlantic species

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    To reconstruct the historical biogeography of Hyla molleri, a tree frog endemic to the Eurosiberian and Mediterranean bioclimatic zones in the Iberian Peninsula. Location: Iberian Peninsul

    Captive Housing during Water Vole (Arvicola terrestris) Reintroduction: Does Short-Term Social Stress Impact on Animal Welfare?

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    Background: Animals captive bred for reintroduction are often housed under conditions which are not representative of their preferred social structure for at least part of the reintroduction process. Specifically, this is most likely to occur during the final stages of the release programme, whilst being housed during transportation to the release site. The degree of social stress experienced by individuals during this time may negatively impact upon their immunocompetence. Methodology/Principal Findings: We examined two measure of stress - body weight and Leukocyte Coping Capacity (LCC) - to investigate the effects of group size upon captive-bred water voles destined for release within a reintroduction program. Water voles were housed in laboratory cages containing between one and eight individuals. LCC scores were negatively correlated with group size, suggesting that individuals in larger groups experienced a larger degree of immunosuppression than did individuals housed in smaller groups or individually. During the course of the study mean body weights increased, in contrast to expectations from a previous study. This was attributed to the individuals sampled being sub-adults and thus growing in length and weight during the course of the investigation. Conclusions/Significance: The reintroduction process will inevitably cause some stress to the release cohort. However, for water voles we conclude that the stress experienced may be reduced by decreasing group size within captive colony and/or transportation housing practises. The findings are of significance to other species' reintroductions, in highlighting the need to consider life-history strategies when choosing housing systems for animals being maintained in captivity prior to release to the wild. A reduction in stress experienced at the pre-release stage may improve immunocompetence and thus animal welfare and initial survival post-release

    Development of electric resistance sintering process for the fabrication of hard metals: Processing, microstructure and mechanical properties

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    This work presents the development of the Electrical Resistance Sintering (ERS) process for the fabrication of hard metals. The compositions of the materials produced were WC with 6 and 10 wt% of Co. In addition to the specific characteristics of the technology, the characterization of the produced parts is presented and compared to materials obtained by conventional processes. The parts produced by ERS present densities comparable to the ones obtained by conventional methods. The microstructural comparison shows a considerable grain size reduction in the ERS materials which consequently brings a hardness increase. ERS materials show similar fracture toughness to conventional ones. The very fast sintering allows performing the process without any protective atmosphere, therefore making this process very attractive for the production of materials that need to be sintered under non-oxidising environments. The total duration of the cycle, including heating, holding time and cooling is few seconds. Finally, some considerations about the scale up and possible industrialization of the technology are explained.This work is financially supported by the Seventh Framework Program of the Commission of the European Communities under project EFFIPRO contract no. NMP2-SL-2013-608729

    Potential relation of cardiovascular risk factors to disease activity in patients with axial spondyloarthritis

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    Background: Axial spondyloarthritis (axSpA) patients are known to have a higher prevalence of several comorbidities, including, among others, an increased risk of atherosclerosis, hypertension, dyslipidemia, and diabetes. The purpose of the present study was to determine whether the sum of traditional cardiovascular (CV) risk factors is related to disease characteristics, such as disease activity, in patients with axSpA. Methods: A cross-sectional study that encompassed 804 patients with axSpA was conducted. Patients were assessed for the presence of five traditional CV risk factors (diabetes mellitus, dyslipidemia, hypertension, obesity, and smoking status), and disease activity measurements. A multivariable regression analysis was performed to evaluate whether the number of classic CV risk factors was independently associated with specific features of the disease, to include disease activity. Results: A multivariable analysis showed that Ankylosing Spondylitis Disease Activity Score-C reactive protein (ASDAS-CRP) activity score was significantly higher in patients with 1 [beta coefficient 0.3 (95% confidence interval (CI) 0.1-0.5), p = 0.001] and ?2 [beta coefficient 0.5 (95% CI 0.3-0.7), p = 0.000] CV risk factors compared with those without CV risk factors. Similarly, patients with 1 [OR 2.00 (95%CI 0.99-4.02), p = 0.053] and ?2 [OR 3.39 (95%CI 1.82-6.31), p = 0.000] CV risk factors had a higher odds ratio for the presence of high disease activity compared with the zero CV category. The Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) activity score was significantly associated with the number of CV risk factors, being higher in patients with more CV risk factors. These relationships showed a CV risk factor-dependent effect being beta coefficients and ORs higher for the effect of ?2 over 1 CV risk factor. Conclusion: Among patients with axSpA, as the number of traditional CV risk factors increased, disease activity similarly increases in an independent manner.Funding: The authors disclosed receipt of the following financial support for the research, authorship, and/ or publication of this article: This research was funded by a grant to MAG-G from the Instituto de Salud Carlos III (ISCIII) (Fondo de Investigación Sanitaria grants PI06/0024, PI09/00748, PI12/00060, PI15/00525, PI18/00043) and the ISCIII RETICS programs (RD12/0009 and RD16/0012)

    Unraveling the effect of silent, intronic and missense mutations on VWF splicing: contribution of next generation sequencing in the study of mRNA

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    Large studies in von Willebrand disease patients, including Spanish and Portuguese registries, led to identification of >250 different mutations. It is a challenge to determine the pathogenic effect of potential splice site mutations on VWF mRNA. This study aimed to elucidate the true effects of 18 mutations on VWF mRNA processing, investigate the contribution of next-generation sequencing to in vivo mRNA study in von Willebrand disease, and compare the findings with in silico prediction. RNA extracted from patient platelets and leukocytes was amplified by RT-PCR and sequenced using Sanger and next generation sequencing techniques. Eight mutations affected VWF splicing: c.1533+1G>A, c.5664+2T>C and c.546G>A (p.=) prompted exon skipping; c.3223-7_3236dup and c.7082-2A>G resulted in activation of cryptic sites; c.3379+1G>A and c.7473G>A (p.=) demonstrated both molecular pathogenic mechanisms simultaneously; and the p.Cys370Tyr missense mutation generated two aberrant transcripts. Of note, the complete effect of 3 mutations was provided by next generation sequencing alone because of low expression of the aberrant transcripts. In the remaining 10 mutations, no effect was elucidated in the experiments. However, the differential findings obtained in platelets and leukocytes provided substantial evidence that 4 of these would have an effect on VWF levels. In this first report using next generation sequencing technology to unravel the effects of VWF mutations on splicing, the technique yielded valuable information. Our data bring to light the importance of studying the effect of synonymous and missense mutations on VWF splicing to improve the current knowledge of the molecular mechanisms behind von Willebrand disease.info:eu-repo/semantics/publishedVersio
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