99 research outputs found
Development and characterization of a new natural fiber reinforced thermoplastic (NFRP) with Cortaderia selloana (Pampa grass) short fibers
[EN] In this work, fully bio-based thermoplastic composites are manufactured with bio-based polyethylene (from sugarcane) and short fibers coming from Cortaderia selloana (CS) wastes. These wastes are characterized by high cellulose content, which can provide high stiffness to the polymeric matrix. The effect of Cortaderia selloana short fibers on thermal properties has been evaluated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The effect of the filler load on mechanical properties has also been evaluated by tensile and impact tests as well as the effects of different coupling agents. Fiber-matrix interactions have been studied by scanning electron microscopy (SEM). The addition of 15-30 wt% Cortaderia selloana short fiber leads to high elastic and flexural modulus without remarkable changes in thermal degradation of the polymer composite. (C) 2017 Elsevier Ltd. All rights reserved.This work was funded by the Conselleria d'Educacio, Cultura i Esport (Generalitat Valenciana) Ref: GV/2014/008. The authors declare that they have no conflict of interest.Jorda-Vilaplana, A.; Carbonell-Verdu, A.; Samper, M.; Pop, A.; García Sanoguera, D. (2017). Development and characterization of a new natural fiber reinforced thermoplastic (NFRP) with Cortaderia selloana (Pampa grass) short fibers. Composites Science and Technology. 145:1-9. https://doi.org/10.1016/j.compscitech.2017.03.036S1914
Victimization and peer and parents attachment: The mediating effect of regulatory emotional self-efficacy
Studies of the Spanish adolescent population has concluded that victimization is related to lack of emotional regulation and impulse control. Therefore, if a victim is unable to recognize, understand and regulate their emotions, this can result in rejection by their peers. A cross-sectional study was conducted to examine regulatory emotional self-efficacy as a possible mediator in the association between peer and parents attachment and victimization. Adolescents (n = 563) completed Regulatory Emotional Self-Efficacy, Inventory of Parents and Peer Attachment and Kid at School questionnaires. Structural equation models (SEMs) were used to predict a latent variable of victimization with parents and peer attachment, emphasizing the mediating role of regulatory emotional self-efficacy, as comprised by a positive and a negative aspect. Results showed that peer attachment had an indirect negative effect, through perceived self-efficacy, in managing a positive effect in victimization, while father attachment had an indirect negative affect, through perceived self-efficacy, in managing a negative affect in victimization, and Mother attachment had no statistically significant indirect effect in victimization. This study suggests that the roles of parents and peers, and also between mothers and fathers, are different in relation to the perception of victimization of adolescents. Findings provide relevant information regarding implications for prevention and intervention in victimization
Evaluation of GenoFlow DR-MTB array test for detection of rifampin and isoniazid resistance in mycobacterium tuberculosis
The aim of this study was to evaluate the GenoFlow DR-MTB array test (DiagCor Bioscience, Hong Kong) on 70 cultured isolates and 50 sputum specimens. The GenoFlow array test showed good sensitivity and specificity compared to the phenotypic Bactec 460TB. This array accurately detected mutations in rpoB, katG, and inhA associated with resistance to rifampin and isoniazid
Análisis del compromiso deportivo de jóvenes waterpolistas: Un estudio basado en la Teoría de la AutoDeterminación
Fundamentado en la Teoría de la Autodeterminación (TAD), el objetivo del estudio fue analizar la relación entre la percepción de jóvenes waterpolistas sobre el estilo interpersonal del entrenador, la satisfacción y frustración de sus necesidades psicológicas básicas (NPB), la motivación autodeterminada y su compromiso deportivo. Participaron 77 jugadores de waterpolo con una edad comprendida entre los 13 y los 20 años (M = 15.00, DT = 1.70). Los resultados mostraron que la percepción de los jugadores de un estilo de apoyo a la autonomía del entrenador, la satisfacción de las NPB, la motivación intrínseca y el compromiso deportivo se relacionaba positiva y significativamente, siguiendo la secuencia establecida en la TAD. En sentido contrario, el estilo controlador percibido por los jugadores se relacionaba positiva y significativamente con la frustración de las NPB y la desmotivación y negativamente con el compromiso deportivo. Los resultados destacan la importancia del estilo interpersonal del entrenador sobre los procesos motivacionales y el compromiso deportivo de los jóvenes waterpolistas.
Grounded in Self-Determination Theory (SDT), the aim of this study was to analyze the relationship between waterpolo players perception on coach interpersonal style, satisfaction and frustration of their basic psychological needs (BPN), self-determined motivation and sport commitment. 77 male water polo players, with ages between 13 and 20 years old (M = 15.00, SD = 1.70), took part in the study. Results showed that players' perception of autonomy support coaching style was related positively and significantly with the satisfaction of BPN, intrinsic motivation and sport commitment, following established sequence in SDT. However, controlling coaching style was related positively and significantly with the frustration of BPN, amotivation and negatively with sport commitment. The results highlight the importance of coach interpersonal style on motivational processes and the sports commitment of young water polo players
Historia de la lucha antituberculosa
La tuberculosis es una de las enfermedades más terribles que afectan al hombre; su antigüedad se estima entre 15 000 a 20 000 años. La historia de la lucha antituberculosa se inicia con el surgimiento y desarrollo de la civilización, vinculada a los conocimientos que sobre la enfermedad existían en cada época especifica de la evolución humana. Un sinnúmero de rituales, remedios y fármacos se han empleado a lo largo de la historia en aras de erradicar este peligroso flagelo; en la actualidad numerosas investigaciones y cuantiosos recursos se dedican a la búsqueda de nuevos medicamentos y vacunas con posibilidades terapéuticas futuras, pues aún, en los inicios del siglo XXI, el Mycobaterium tuberculosis sigue causando la muerte de millones de personas y enfrentando nuevos retos como TB/VIH & MDR-TB. Palabras clave: Tisis, bacilífero, broncopleurales, pleuropulmonares
La situación de la Historia de la Psicología en el currículo del psicólogo
Después de revisar diversos programas de la asignatura de Historia de la Psicología a partir de las páginas Web de 73 universidades españolas, presentamos un análisis de la asignatura en los planes de estudio actuales de la licenciatura de psicología. En la mayoría de universidades es una asignatura troncal, de Primer Ciclo y semestral, a excepción de algunos casos en los que es anual y de segundo ciclo. El número de créditos varía desde 4,5 a 9 créditos LRU y desde 4 a 9 créditos ECTS. La revisión temática de los diferentes programas completa el estudio. La aproximación a la situación actual de dicha asignatura nos sirve de punto de partida para justifi car su presencia en la futura propuesta de Grado en Psicología y su ubicación en el diseño de los planes de estudio según el Real Decreto para la regulación de las Enseñanzas Universitarias en el Espacio Europeo de Educación Superior
Development of slate fiber reinforced high density polyethylene composites for injection molding
During the last decade the use of fiber reinforced composite materials has consolidated as an attracting alternative to traditional materials due to an excellent balance between mechanical properties and lightweight. One drawback related to the use of inorganic fibers such as those derived from siliceous materials is the relative low compatibility with conventional organic polymer matrices. Surface treatments with coupling agents and the use of copolymers allow increasing fiber-matrix interactions which has a positive effect on overall properties of composites. In this research work we report the use of slate fiber treated with different coupling agents as reinforcement for high density polyethylene from sugarcane. A silane (propyltrimethoxy silane; PTMS) and a graft copolymer (polyethylene-graft-maleic anhydride; PE-g-MA) were used to improve fiber-matrix interactions on HOPE-slate fiber. The effect of the different compatibilizing systems and slate fiber content were evaluated by scanning electron microscopy (SEM), dynamic thermomechanical analysis (DTMA) as well as mechanical properties (tensile, flexural and impact). The results show that the use of silane coupling agents leads to higher fiber-matrix interactions which has a positive effect on overall mechanical properties. Interesting results are obtained for composites containing 30 wt.% slate fiber previously treated with propyltrimethoxy silane (PTMS) with an increase in tensile and flexural strength of about 16% and 18% respectively. (C) 2014 Elsevier Ltd. All rights reserved.Authors thank "Ministerio de Economia y Competitividad" ref: MAT2011-28468-C02-02 and "Conselleria d'Educacio, Cultura i Esport" - Generalitat Valenciana ref: GV/2014/008 for financial support.Carbonell Verdú, A.; García García, D.; Jordá Vilaplana, A.; Samper Madrigal, MD.; Balart Gimeno, RA. (2015). Development of slate fiber reinforced high density polyethylene composites for injection molding. Composites Part B: Engineering. 69:460-466. https://doi.org/10.1016/j.compositesb.2014.10.026S4604666
Recommendations for ophthalmologic practice during the easing of COVID-19 control measures
In the context of the COVID-19 pandemic, this paper provides recommendations for medical eye care during the easing of control measures after lockdown. The guidelines presented are based on a literature review and consensus among all Spanish Ophthalmology Societies regarding protection measures recommended for the ophthalmologic care of patients with or without confirmed COVID-19 in outpatient, inpatient, emergency and surgery settings. We recommend that all measures be adapted to the circumstances and availability of personal protective equipment at each centre and also highlight the need to periodically update recommendations as we may need to readopt more restrictive measures depending on the local epidemiology of the virus. These guidelines are designed to avoid the transmission of SARS-CoV-2 among both patients and healthcare staff as we gradually return to normal medical practice, to prevent postoperative complications and try to reduce possible deficiencies in the diagnosis, treatment and follow-up of the ophthalmic diseases. With this update (5th) the Spanish Society of Ophthalmology is placed as one of the major ophthalmology societies providing periodic and systematized recommendations for ophthalmic care during the COVID-19 pandemic
ATR suppresses telomere fragility and recombination but is dispensable for elongation of short telomeres by telomerase
ATR recognizes critically short telomeres as fragile sites and protects them from chromosomal fusions
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