2,016 research outputs found

    On the performance of SQL scalable systems on Kubernetes: a comparative study

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    The popularization of Hadoop as the the-facto standard platform for data analytics in the context of Big Data applications has led to the upsurge of SQL-on-Hadoop systems, which provide scalable query execution engines allowing the use of SQL queries on data stored in HDFS. In this context, Kubernetes appears as the leading choice to simplify the deployment and scaling of containerized applications; however, there is a lack of studies about the performance of SQL-on-Hadoop systems deployed on Kubernetes, and this is the gap we intend to fill in this paper. We present an experimental study involving four representative SQL scalable platforms: Apache Drill, Apache Hive, Apache Spark SQL and Trino. Concretely, we analyze the performance of these systems when they are deployed on a Hadoop cluster with Kubernetes by using the TPC-H benchmark. The results of our study can help practitioners and users about what they can expect in terms of performance if they plan to use the advantages of Kubernetes to deploy applications using the analyzed SQL scalable platforms.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. Funding for open access charge: Universidad de Málaga / CBUA. This work has been partially funded by the Spanish Ministry of Science and Innovation via Grant PID2020-112540RB-C41 (AEI/FEDER, UE), Andalusian PAIDI program with grant P18-RT-2799, and by project ”Evolución y desarrollo de la plataforma DOP de Big Data” (702C2000044) under Andalusian “Programa de Apoyo a la I+D+i Empresarial”

    Marcas de Distribuidores (mdd) en Colombia. Y usted qué piensa de las marcas de distribuidor?

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    Este artículo tiene como fin conocer la opinión de la gente sobre las marcas de distribuidor, para así establecer qué porcentaje de personas compra de estas marcas y qué aspectos tienen en cuenta a la hora de hacerlo. Es importante resaltar que algunos de los atributos que se asocian a las marcas de los distribuidores son el precio y la calidad. Para esto se realizaron encuestas en diferentes supermercados, como Carrefour, Éxito, Olímpica, Cafam y Colsubsidio en los cuatro puntos cardinales de la ciudad. Luego de la investigación realizada por medio de encuestas se puede deducir la buena aceptación que existe en la ciudad de Bogotá por parte de los ciudadanos hacia los artículos o bienes marca distribuidor

    Caracterización de una fuente UV-C de bajo costo y alta eficiencia germicida para la esterilización de superficies e implementos de uso crítico diario: impacto en la salud pública

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    Mediante la modificación y caracterización de una lámpara comercial de mercurio halogenado de bajo costo, se diseñó una fuente UV-C altamente eficiente que posee un poder germicida igual o superior a fuentes UV-C comerciales diseñadas para tal fin. Desde un punto de vista físico, la ventaja de usar este tipo de lámparas es que presentan un amplio espectro de radiación UV: UV-A, UV-B y UV-C. Este último caso, en particular, la denominada zona germicida presenta un espectro de emisión con múltiples líneas, con longitudes de onda que van desde los 220 hasta los 280 nm; en particular, presentan máximos de emisión de las líneas espectrales con longitudes de onda entre 235 y 260 nm que destruyen tanto el ADN como las proteínas. Los resultados que se presentan son el resultado de estudios preliminares desarrollados en el laboratorio, en los cuales se irradiaron muestras que contenían bacterias in vitro, y se encontró una esterilización efectiva para tiempo de exposición por debajo de los 60 s para una distancia fuente-muestra de 35 cm y con una densidad de energía UV-C estimada de 1 W.s/m 2 . Los resultados obtenidos indican que el dispositivo construido con elementos de muy bajo costo y de fácil implementación es apto para la desinfección de superficies y recuperación de material descartable

    Nitrogen-carbon graphite-like semiconductor synthesized from uric acid

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    A new carbon-nitrogen organic semiconductor has been synthesized by pyrolysis of uric acid. This layered carbon-nitrogen material contains imidazole-, pyridine (naphthyridine)- and graphitic-like nitrogen, as evinced by infrared and X-ray photoelectron spectroscopies. Quantum chemistry calculations support that it would consist of a 2D polymeric material held together by hydrogen bonds. Layers are stacked with an interplanar distance between 3.30 and 3.36 Å, as in graphite and coke. Terahertz spectroscopy shows a behavior similar to that of amorphous carbons, such as coke, with non-interacting layers. This material features substantial differences from polymeric carbon nitride, with some characteristics closer to those of nitrogen-doped graphene, in spite of its higher nitrogen content. The direct optical band gap, dependent on the polycondensation temperature, ranges from 2.10 to 2.32 eV. Although in general the degree of crystallinity is low, in the material synthesized at 600 °C some spots with a certain degree of crystallinity can be found

    Chronic Skin Disease and Levels of Physical Activity in 17,777 Spanish Adults: A Cross-Sectional Study

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    Background: To date there is limited literature on the prevalence of chronic skin conditions and levels of physical activity (PA) in Spain. Aim: The present study aims to (i) determine the prevalence of chronic skin disease and (ii) compare levels of PA in those with chronic skin disease to those without in a large representative sample of Spanish adults aged 15‐69 years. Methods: Data from the Spanish National Health Survey 2017 were analysed. Chronic skin disease was assessed using a yes‐no question. PA was measured using the short form of the International Physical Activity Questionnaire (IPAQ). Total PA metabolic equivalent of task (MET)‐minutes/week were calculated, and PA was included in the analyses as a continuous and a five‐category variable. Results: This cross‐sectional study included 17,777 participants [52.0% women; mean (standard deviation) age 45.8 (14.1) years]. There were 940 (5.3%) adults with chronic skin disease. After adjusting for several potential confounders, there was a negative association between chronic skin disease and PA [odds ratio (OR)=0.87, 95% CI=0.76–1.00]. The association was significant in men (OR=0.76, 95% CI=0.62‐0.93) but not in women (OR=0.97, 95% CI=0.81‐1.16). Conclusions: In this large representative sample of Spanish adults, the prevalence of chronic skin disease was low. Levels of PA in men with chronic skin conditions, but not in women, were lower than those without

    Mamíferos, historia natural y colecciones

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    In this issue of Mammalogy Notes, we feature three notes on range extension, seven notes on natural history, and four inventories of mammals. Contributions come from Colombia, Peru, Mexico, Brazil, and Venezuela. Additionally, we include three new contributions from the special series on biological collections of Colombian mammals. In this way, Mammalogy Notes keeps growing, improving, and contributing to the knowledge of neotropical mammals.En este número de Mammalogy Notes presentamos tres notas sobre extensiones de distribución, siete notas de historia natural y cuatro inventarios de mamíferos. Las contribuciones provienen de Colombia, Perú, México, Brasil y Venezuela. Adicionalmente, incluimos tres nuevos trabajos de la serie especial sobre colecciones de mamíferos de Colombia. De esta forma Mammalogy notes continúa creciendo, mejorando y aportando al conocimiento de los mamíferos neotropicales

    Prevalence of Erectile Dysfunction in Male Cancer Survivors: a Systematic Review and Meta-Analysis of Cross-Sectional Studies

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    Background: Sexual function is a fundamental aspect of health, well being and quality of life. In oncological male patients sexuality and erectile dysfunction (ED) can be compromise by psychological, pharmacological or physical components. Aim: We conducted a meta-analysis to estimate the prevalence of ED in all types of cancer and identify characteristics associated with ED in cancer survivors. Design and Setting: Systematic review and meta-analysis of cross-sectional studies. Method: Random effects models were used to pool the prevalence of ED as absolute estimates at three different stages (i.e., healthy, at diagnosis, and after treatment stages). A univariate meta-analysis (MA) regression including the three-level group variable as the only independent variable was used to assess the difference of prevalence of ED across the three groups. Further MA were conducted for studies involving patients at diagnosis and after treatment. Graphical comparisons of the prevalence of ED across these two stages of cancer treatment were given by a classic forest plot. Results: We included 43 studies with a total of 19,329 participants. Overall the pooled data of the included studies showed an ED prevalence of 40.72% (95%CI: 31.80-50.29) in cancer patients, with prevalence of 28.60% (95%CI: 12.10%-53.83%) at time of diagnosis and 42.70% (95%CI: 32.97%-53.03%) after treatment, across cancer locations. Conclusion: ED is particularly high in oncologic patients and may be influenced by neurovascular damage associated with treatment, hormonal therapy systemic chemo- or radiation therapy, as well as by psychological factors such as depression, anxiety, low self-esteem or issues with body image

    Identification of Marine Biotechnology Value Chains with High Potential in the Northern Mediterranean Region

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    © 2023. The authors. This document is made available under the CC-BY 4.0 license http://creativecommons.org/licenses/by /4.0/ This document is the Accepted version of a Published Work that appeared in final form in Marine Drugs. To access the final edited and published work see https://doi.org/10.3390/md21070416Marine (blue) biotechnology is an emerging field enabling the valorization of new products and processes with massive potential for innovation and economic growth. In the Mediterranean region, this innovation potential is not exploited as well as in other European regions due to a lack of a clear identification of the different value chains and the high fragmentation of business innovation initiatives. As a result, several opportunities to create an innovative society are being missed. To address this problem, eight Northern Mediterranean countries (Croatia, France, Greece, Mar. Drugs 2023, 21, 416. https://doi.org/10.3390/md21070416 https://www.mdpi.com/journal/marinedrugs Mar. Drugs 2023, 21, 416 2 of 26 Italy, Montenegro, Portugal, Slovenia and Spain) established five national blue biotechnology hubs to identify and address the bottlenecks that prevent the development of marine biotechnology in the region. Following a three-step approach (1. Analysis: setting the scene; 2. Transfer: identification of promising value chains; 3. Capitalization: community creation), we identified the three value chains that are most promising for the Northern Mediterranean region: algae production for added-value compounds, integrated multi-trophic aquaculture (IMTA) and valorization aquaculture/fisheries/processing by-products, unavoidable/unwanted catches and discards. The potential for the development and the technical and non-technical skills that are necessary to advance in this exciting field were identified through several stakeholder events which provided valuable insight and feedback that should be addressed for marine biotechnology in the Northern Mediterranean region to reach its full potential

    Identification of Marine Biotechnology Value Chains with High Potential in the Northern Mediterranean Region

    Get PDF
    ©2023. This manuscript version is made available under the CC-BY 4.0 license http://creativecommons.org/licenses/by/4.0/ This document is the Published, version of a Published Work that appeared in final form in Marine Drugs. To access the final edited and published work see https://doi.org/ 10.3390/md21070416Marine (blue) biotechnology is an emerging field enabling the valorization of new products and processes with massive potential for innovation and economic growth. In the Mediterranean region, this innovation potential is not exploited as well as in other European regions due to a lack of a clear identification of the different value chains and the high fragmentation of business innovation initiatives. As a result, several opportunities to create an innovative society are being missed. To address this problem, eight Northern Mediterranean countries (Croatia, France, Greece Italy, Montenegro, Portugal, Slovenia and Spain) established five national blue biotechnology hubs to identify and address the bottlenecks that prevent the development of marine biotechnology in the region. Following a three-step approach (1. Analysis: setting the scene; 2. Transfer: identifi cation of promising value chains; 3. Capitalization: community creation), we identified the three value chains that are most promising for the Northern Mediterranean region: algae production for added-value compounds, integrated multi-trophic aquaculture (IMTA) and valorization aquacul ture/fisheries/processing by-products, unavoidable/unwanted catches and discards. The potential for the development and the technical and non-technical skills that are necessary to advance in this exciting field were identified through several stakeholder events which provided valuable insight and feedback that should be addressed for marine biotechnology in the Northern Mediterranean region to reach its full potential

    The KiVa antibullying program in primary schools in Chile, with and without the digital game component: study protocol for a randomized controlled trial.

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    BACKGROUND: Bullying is a major problem worldwide and Chile is no exception. Bullying is defined as a systematic aggressive behavior against a victim who cannot defend him or herself. Victims suffer social isolation and psychological maladjustment, while bullies have a higher risk for conduct problems and substance use disorders. These problems appear to last over time. The KiVa antibullying program has been evaluated in Finland and other European countries, showing preventive effects on victimization and self-reported bullying. The aims of this study are (1) to develop a culturally appropriate version of the KiVa material and (2) to test the effectiveness of the KiVa program, with and without the online game, on reducing experiences of victimization and bullying behavior among vulnerable primary schools in Santiago (Chile), using a cluster randomized controlled trial (RCT) design with three arms: (1) full KiVa program group, (2) partial KiVa (without online game) program group and (3) control group. METHODS AND DESIGN: This is a three-arm, single-blind, cluster randomized controlled trial (RCT) with a target enrolment of 1495 4th and 5th graders attending 13 vulnerable schools per arm. Students in the full and partial KiVa groups will receive universal actions: ten 2-h lessons delivered by trained teachers during 1 year; they will be exposed to posters encouraging them to support victims and behave constructively when witnessing bullying; and a person designated by the school authorities will be present in all school breaks and lunchtimes using a visible KiVa vest to remind everybody that they are in a KiVa school. KiVa schools also will have indicated actions, which consist of a set of discussion groups with the victims and with the bullies, with proper follow-up. Only full KiVa schools will also receive an online game which has the aim to raise awareness of the role of the group in bullying, increase empathy and promote strategies to support victimized peers. Self-reported victimization, bullying others and peer-reported bullying actions, psychological and academic functioning, and sense of school membership will be measured at baseline and 12 months after randomization. DISCUSSION: This is the first cluster RCT of the KiVa antibullying program in Latin America. TRIAL REGISTRATION: ClinicalTrials.gov, Identifier: NCT02898324 . Registered on 8 September 2016
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