38 research outputs found

    Three-Dimensional Wave Packet Approach for the Quantum Transport of Atoms through Nanoporous Membranes

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    Quantum phenomena are relevant to the transport of light atoms and molecules through nanoporous two-dimensional (2D) membranes. Indeed, confinement provided by (sub-)nanometer pores enhances quantum effects such as tunneling and zero point energy (ZPE), even leading to quantum sieving of different isotopes of a given element. However, these features are not always taken into account in approaches where classical theories or approximate quantum models are preferred. In this work we present an exact three-dimensional wave packet propagation treatment for simulating the passage of atoms through periodic 2D membranes. Calculations are reported for the transmission of 3^3He and 4^4He through graphdiyne as well as through a holey graphene model. For He-graphdiyne, estimations based on tunneling-corrected transition state theory are correct: both tunneling and ZPE effects are very important but competition between each other leads to a moderately small 4^4He/3^3He selectivity. Thus, formulations that neglect one or another quantum effect are inappropriate. For the transport of He isotopes through leaky graphene, the computed transmission probabilities are highly structured suggesting widespread selective adsorption resonances and the resulting rate coefficients and selectivity ratios are not in agreement with predictions from transition state theory. Present approach serves as a benchmark for studies of the range of validity of more approximate methods.Comment: 4 figure

    Bibliometric analysis of the global scientific production on machine learning applied to different cancer types

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    This work has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska Curie grant agreement no. 860627 (CLARIFY Project), from the Spanish Ministry of Science and Innovation under project PID2019-105142RB-C22, and by FEDER/Junta de Andalucia-Consejeria de Transformacion Economica, Industria, Conocimiento y Universidades under the project P20_00286. Funding for open access charge: Universidad de Granada/CBUA.Cancer disease is one of the main causes of death in the world, with million annual cases in the last decades. The need to find a cure has stimulated the search for efficient treatments and diagnostic procedures. One of the most promising tools that has emerged against cancer in recent years is machine learning (ML), which has raised a huge number of scientific papers published in a relatively short period of time. The present study analyzes global scientific production on ML applied to the most relevant cancer types through various bibliometric indicators. We find that over 30,000 studies have been published so far and observe that cancers with the highest number of published studies using ML (breast, lung, and colon cancer) are those with the highest incidence, being the USA and China the main scientific producers on the subject. Interestingly, the role of China and Japan in stomach cancer is correlated with the number of cases of this cancer type in Asia (78% of the worldwide cases). Knowing the countries and institutions that most study each area can be of great help for improving international collaborations between research groups and countries. Our analysis shows that medical and computer science journals lead the number of publications on the subject and could be useful for researchers in the field. Finally, keyword co-occurrence analysis suggests that ML-cancer research trends are focused not only on the use of ML as an effective diagnostic method, but also for the improvement of radiotherapy- and chemotherapy-based treatments.Horizon 2020 European Union under the Marie Sklodowska Curie 860627Spanish Government PID2019-105142RB-C22FEDER/Junta de Andalucía-Consejería de Transformación Económica, Industria, Conocimiento y Universidades P20_00286Universidad de Granada/CBU

    Water relation response to soil chilling of six olive (Olea europaea L) cultivars with different frost resistance

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    The relationship between the water relations of six olive cultivars exposed to different soil temperatures (14 0.1, 9.9 0.1 and 5.8 0.2°C) and their inherent frost resistance (as determined by two different methods) was investigated. Soil chilling was achieved by introducing pots of olive plants into water baths. The water relations of these plants were compared to those of plants kept under conditions of room temperature. The cultivars Frantoio, Picual and Changlot Real began to show significant dehydration below 14°C, while Cornicabra, Arbequina and Ascolana Tenera showed this below 10°C. This response is probably due to delayed stomatal closure. Only Cornicabra and Picual showed a significant reduction in leaf conductance (below 10°C and 6°C respectively). This absence of stomatal control led to a significantly greater dehydration in Ascolana Tenera. These variations in response to the soil chilling temperature suggest that different mechanisms may be at work, and indicate that would be necessary to study the influence of rootstock in the frost resistance of olive plants. The variations recorded grouped the cultivars as either resistant (Cornicabra), tolerant (Picual, Ascolana Tenera and Arbequina), or sensitive (Frantoio and Changlot Real). This classification is in line with the frost resistance reported for these cultivars in the literature, and with the results obtained in the present work using the stomatal density and ion leakage methods of determining such resistance.Se ha investigado la relación existente entre el estado hídrico de 6 variedades de olivo expuestas a diferentes temperaturas del suelo y su resistencia al frío (determinada por dos métodos). El frío del suelo fue conseguido introduciendo las macetas de las plantas de olivo en baños de agua. Se comparó el estado hídrico de estas plantas con el de plantas en condiciones de temperatura ambiente. Las variedades Frantoio, Picual y Changlot Real comenzaron a mostrar una deshidratación significativa por debajo de 14°C, mientras que para Cornicabra, Arbequina y Ascolana Tenera lo fue por debajo de 10°C. Esta respuesta es posiblemente debida a un retraso en el cierre estomático. Solamente Cornicabra y Picual mostraron una reducción significativa de la conductancia de la hoja (por debajo de 10°C y 6°C respectivamente). Esta ausencia de control estomático condujo a una significativa mayor deshidratación en Ascolana Ternera. Estas variaciones en respuesta al frío en el suelo sugieren diferentes mecanismos de actuación, e indican que la utilización de un portainjerto puede dar resistencia al frío en plantas de olivo. Los datos agruparon las variedades como resistentes (Cornicabra), tolerantes (Picual, Ascolana Tenera y Arbequina) o sensibles (Frantoio y Changlot Real). Esta clasificación está en consonancia con la resistencia a frío que se recoge en la literatura para estas variedades, y con los resultados obtenidos en este trabajo usando los métodos de densidad estomática y liberación de iones para determinar dicha resistencia

    Ultrasound Examination of the Ligament Complex Within the Medial Aspect of the Ankle and Foot

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    To properly diagnose and treat injuries to the ankle or foot, the physician must have good anatomical knowledge of the ligaments involved. The bundles can be distinguished and identified by ultrasound examination of the medial aspect, but this may be a challenging task. In the present illustrated study, we discuss how a detailed ultrasound examination can be made of the different ligaments within the medial aspect of the ankle and foot.Funding for open access charge is provided by Universidad de Malaga/CBU

    The influence of sock composition on the appearance of foot blisters in hikers

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    Introduction: Socks are of fundamental importance in reducing friction and in controlling the temperature and humidity of the foot, thus preventing the appearance of blisters. However, the influence of sock fibres (synthetic vs. natural) on blistering during long-distance hiking has received little research attention. Aims: This study evaluates the influence of sock fibres on the appearance of foot blisters in hikers. Method: The sample consisted of 203 male and female hikers, mean age 35.8 ± 14.5 years, from 22 countries. All were interviewed and assessed at shelters on the French route of the Camino de Santiago (Spain). Sociodemo- graphic and clinical data were obtained for each hiker; other study data included the number of blisters on the foot, whether the socks were wet at the end of the day, the model of sock used and the nature of its constituent fibres. Results: Among the hikers interviewed, 68.5% presented foot blisters. 74.2% used socks with predominantly synthetic fibres, compared to 25.9% whose socks were mainly composed of natural fibres. On average, they had walked 253.7 km. Hiking in wet socks was associated with a 1.94 times greater risk of experiencing foot blisters (95% CI 1.04–3.61) (p = 0.035). Multivariate analysis showed that the proportion of natural/synthetic fibres in the composition of the sock was not related to the presence of blisters. Conclusions: The use of wet socks heightens the risk of foot blisters in hikers, but the composition of the sock is not associated with blistering. We recommend hikers change their socks in long stages to maintain feet dry and so avoiding the appereance of blistersUniversidad de Málaga. Campus de Excelencia Internacional Andalucía TEC

    Establishing normative foot posture index values for the paediatric population: a cross-sectional study

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    Antecedentes: el índice de postura del pie (FPI) es una herramienta de observación diseñada para medir la posición del pie. Su fiabilidad está bien establecida y proporciona valores de referencia normativos para la población en general. Sin embargo, esto no es así para la población pediátrica. El objetivo de este estudio es determinar los valores de referencia de FPI en la infancia, teniendo en cuenta la edad y el sexo. Métodos: este estudio transversal incluyó a 1.762 escolares (863 niños y 899 niñas) de 6 a 11 años, de Málaga, Granada y Plasencia (España). En todos los casos, dos podólogos experimentados obtuvieron las mediciones de FPI en ambos pies. Luego se realizó un análisis descriptivo y se determinaron los percentiles de las variables, con un nivel de significancia de P <0.05. Resultados: Los resultados del FPI consolidado para la población de muestra arrojaron valores medios de 3.74 (SD 2.93) puntos para el pie derecho y 3.83 (SD 2.92) para el izquierdo. El percentil 50 fue de 4 puntos para ambos sexos y para ambos pies, a excepción del pie derecho entre las chicas, que fue ligeramente inferior, en 3 puntos. El percentil 85, que se considera que representa el límite entre el pie normal y el pronado entre los niños, fue de 6 puntos, uniformemente entre los sujetos. Conclusiones: como valor normativo de FPI para la población pediátrica, recomendamos el percentil 50, es decir, 4 puntos, para niños, de ambos sexos, con edades comprendidas entre los 6 años. Este valor disminuye progresivamente con la edad, hasta 3 puntos FPI para niños de 11 años. El percentil 85 para el pie pronated y el percentil 4 para el pie supinado se puede considerar el límite patológico.Background: The Foot Posture Index (FPI) is an observational tool designed to measure the position of the foot. Its reliability is well established, and it provides normative reference values for the general population. However, this is not so for the paediatric population. The aim of this study is to determine FPI reference values in childhood, taking into account age and gender. Methods: This cross-sectional study included 1,762 school children (863 boys and 899 girls) aged 6–11 years, from Málaga, Granada and Plasencia (Spain). In every case, FPI measurements were obtained for both feet by two experienced podiatrists. A descriptive analysis was then conducted and the percentiles of the variables determined, with a significance level of P < 0.05. Results: The consolidated FPI results for the sample population produced mean values of 3.74 (SD 2.93) points for the right foot and 3.83 (SD 2.92) for the left. The 50th percentile was 4 points for both genders and for both feet, except for the right foot among the girls, which was slightly lower, at 3 points. The 85th percentile, which is considered to represent the boundary between the normal and the pronated foot among children, was 6 points, uniformly among the subjects. Conclusions: As a normative FPI value for the paediatric population, we recommend the 50th percentile, i.e. 4 points, for children, of both genders, aged 6 years. This value progressively falls with age, to 3 FPI points for children aged 11 years. The 85th percentile for the pronated foot and the 4th percentile for the supinated foot can be considered the pathological boundary.peerReviewe

    [José Ramón Martínez Galán] [Material gráfico]: [(procurador de las Cortés)]

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    Contiene fotografías pertenecientes al archivo fotográfico del diario "Región", publicadas entre 1967 y 1978Algunas fotos no indican autoría; el resto firmadas por Información Gráfica Sierra (Oviedo), Salvador Hevia (Oviedo), Matilla (Gijón), Estudios Ortega (Sama de Langreo), Alfonso (Madrid

    [Equipos asturianos varios I] [Material gráfico]

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    Contiene fotografías pertenecientes al archivo fotográfico del diario "Región", publicadas entre 1964 y 1983Algunas fotos no indican autoría; el resto firmadas por Foto E. Gar (Oviedo), Foto Sampedro (Las Segadas, Oviedo), Fotos Pantiga (Ciaño), Foto Alfonso (Gijón), Carneado (Gijón), Foto Macías (Avilés), Estudio Fotográfico Hnos. Esteban (Moreda

    Medical students maintain their humanistic and patient‑centred vocation throughout Medicine Degree in Spain: a study based on narratives

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    Narrative medicine has great educational potential in the degree of medicine. This study explores for the frst time the use of narrative medicine in relation to longitudinal evolution of medical vocation for the same group of students. In the context of the Degree in Medicine at the Universidad Autónoma de Madrid (Spain), students wrote narratives about what it meant to them to be a doctor at the beginning and end of their studies. The narratives of 338 students of the academic years 2012/13– 2017/18 and 2013/14–2018/19 were analysed and compared. Students mostly pursued a degree in medicine on account of humanistic motivations, which are reinforced throughout their degree. In contrast, up to 10% of students reference to have experienced vocational crises and sufered frustration, with up to 25% of the references pertaining to having made signifcant sacrifces. Students maintain and evolve their humanistic, patient-centred vision throughout their degree studies, despite the difculties they appear to encounter. We suggest that eforts must be made to include more humanistic perspectives in the medical degree to keep this trend, which may improve both the educational experience created in universities and the health care given to patient
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