69 research outputs found

    A biobjective model for resource provisioning in multi-cloud environments with capacity constraints

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    Private and public clouds are good means for getting on-demand intensive computing resources. In such a context, selecting the most appropriate clouds and virtual machines (VMs) is a complex task. From the user’s point of view, the challenge consists in efficiently managing cloud resources while integrating prices and performance criteria. This paper focuses on the problem of selecting the appropriate clouds and VMs to run bags-of-tasks (BoT): big sets of identical and independent tasks. More precisely, we define new mathematical optimization models to deal with the time of use of each VMs and to jointly integrate the execution makespan and the cost into the objective function through a bi-objective problem. In order to provide trade-off solutions to the problem, we propose a lexicographic approach. In addition, we introduce, in two different ways, capacity constraints or bounds on the number of VMs available in the clouds. A global limit on the number of VMs or resource constraints at each time period can be defined. Computational experiments are performed on a synthetic dataset. Sensitivity analysis highlights the effect of the resource limits on the minimum makespan, the effect of the deadline in the total operation cost, the impact of considering instantaneous capacity constraints instead of a global limit and the trade-off between the cost and the execution makespan

    Estudio de viabilidad comercial para un nuevo negocio de e-commerce

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    Con el auge de las plataformas de venta online y el constante aumento en la demanda de los productos tecnológico, se plantea un estudio para conocer la viabilidad comercial de un nuevo e-commerce. En este, se plantea la apertura de un negocio dedicado a la venta de determinados artículos, todos ellos ligados a la reconocida marca Xiaomi. Para conseguir los objetivos fijados, tiene lugar un primer análisis sobre la situación actual que está viviendo el sector, su estimación para los próximos años y el impacto que tiene la marca china, en especial sobre el territorio español. Además, se estudia detalladamente el mercado al cual se pretende llegar, desarrollando su entorno competitivo y realizando una investigación de la demanda. Tras esto, se indican de forma más precisa los artículos adecuados que deben incluirse en la cartera de productos inicial. Seguidamente, se plantea un programa de marketing mix en el que se eligen cuáles serían las estrategias a seguir en cuanto a distribución, tareas de comunicación y precios. Por último, se elabora un presupuesto final a través de los costes que generaría en inicio de la actividad comercial, concluyendo con una estimación positiva en cuanto a la viabilidad del nuevo comercio, quedando sujeto a ciertas condiciones.<br /

    Postoperative pain after one-visit root-canal treatment on teeth with vital pulps : comparison of three different obturation techniques

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    Objectives. To investigate and compare postoperative pain after one-visit root canal treatment (RCT) on teeth with vital pulps using three different obturation techniques. Study Design. Two hundred and four patients (105 men and 99 women) aged 12 to 77 years were randomly assigned into three treatments groups: cold lateral compaction of gutta-percha (LC), Thermafil technique (TT), and Backfill - Thermafil obturation technique (BT). Postoperative pain was recorded on a visual analogue scale (VAS) of 0 - 10 after 2 and 6 hours, and 1, 2, 3, 4, 5, 6 and 7 days. Data were statistically analyzed using multivariate logistic regression analysis. Results. In the total sample, 87% of patients experienced discomfort or pain in some moment between RCT and the seventh day. The discomfort experienced was weak, light, moderate and intense in 6%, 44%, 20% and 6% of the cases, respectively. Mean pain levels were 0.4 ± 0.4, 0.4 ± 0.3, and 1.4 ± 0.7 in LC, BT, and TT groups, respectively. Patients of TT group experienced a significantly higher mean pain level compared to other two groups (p < 0.0001). In TT group, all patients felt some level of pain at six hours after RCT. Conclusions. Postoperative pain was significantly associated with the obturation technique used during root canal treatment. Patients whose teeth were filled with Thermafil obturators (TT technique) showed significantly higher levels of discomfort than patients whose teeth were filled using any of the other two techniques

    Combined effectiveness of prior and current season influenza vaccination in northern Spain: 2016/17 mid-season analysis

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    The 2016/17 mid-season vaccine effectiveness estimate against influenza A(H3N2) was 15% (95% confidence interval: -11 to 35) in Navarre. Comparing to individuals unvaccinated in the current and four prior seasons, effectiveness was 24% for current and 3-4 prior doses, 61% for current and 1-2 prior doses, 42% for only current vaccination, and 58% for 3-4 prior doses. This suggests moderate effectiveness for different combinations of vaccination in the current and prior seasons.This study was supported by the Horizon 2020 program of the European Commission (agreement 634446); by the I-MOVE (Influenza Monitoring Vaccine Effectiveness in Europe) Network funded by the European Centre for Disease Prevention and Control; by La Caixa Foundation; and by the Carlos III Institute of Health with the European Regional Development Fund (ERDF) (CM15/00119, INT15/00182).S

    Effectiveness of influenza vaccination in preventing influenza in primary care, Navarre, Spain, 2021/22

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    Compared with individuals unvaccinated in the current and three previous influenza seasons, in 2021/22, influenza vaccine effectiveness at primary care level was 37% (95% CI: 16 to 52) for current season vaccination, regardless of previous doses, and 35% (95% CI: -3 to 45) for only previous seasons vaccination. Against influenza A(H3N2), estimates were 39% (95% CI: 16 to 55) and 24% (95% CI: -8 to 47) suggesting moderate effectiveness of current season vaccination and possible remaining effect of prior vaccinations.This study was supported by the Influenza Monitoring Vaccine Effectiveness in Europe (I-MOVE) Network funded by the European Centre for Disease Prevention and Control (RS/2021/DRP/12984) and by the Instituto de Salud Carlos III with the European Regional Development Fund (PI20/01323, CM19/00154, and INT21/00100).S

    Use of antibiotics by spanish dentists receiving postgraduate training in endodontics

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    The incidence of endodontic infections is high. The contribution of Endodontics to the global problem of antibiotic resistance could be significant. The ESE, together with the World Health Organization, are promoting the World Antibiotic Awareness Week (13-19 November 2017) to promote the appropriate use of systemic antibiotics in Endodontics. The objective of this study was to determine the prescription pattern of antibiotics in the treatment of endodontic infections of Spanish dentists attending specialization programs in Endodontics. Material and Methods: Dentists from five Spanish endodontic postgraduate programs were requested to answer a one-page questionnaire surveying about antibiotics indications. Seventy-three dentists were required to participate in this investigation, and 67 (91.2%) fulfilled satisfactorily the survey and were included in the study. Data were analyzed using descriptive statistics and chi square test. Results: The average duration of antibiotic therapy was 6.8±1.2 days. All respondents chose amoxicillin as first choice antibiotic in patients with no medical allergies, alone (40%) or associated to clavulanic acid (60%). The first drug of choice for penicillin allergic patients was clindamycin (72%). For cases of irreversible pulpitis, 22% of respondents prescribed antibiotics. For the scenario of a necrotic pulp, symptomatic apical periodontitis and no swelling, 37% prescribed antibiotics. A quarter of dentists prescribed antibiotics for necrotic pulps with asymptomatic apical periodontitis and a sinus tract. Conclusions: The results of this study show that postgraduate training in Endodontics provides greater awareness of the correct indications of antibiotics. Dentists who have received specialized training in Endodontics have a prescription pattern of antibiotics more adjusted to the guidelines recommended by international organizations and by scientific societies. Key words:Antibiotics, apical periodontitis, dental curriculum, endodontic infections, postgraduate endodontic training
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