90 research outputs found
The influence of sonication on the thermal behavior of muscovite and biotite
The differences on the thermal behavior (DTA-TG) of mica samples measured
before and after sonication have been studied. Sonication treatment produces
important modifications in the thermal behavior of muscovite and biotite
samples. For muscovite, it produces a broadening and decrease in temperature of
the dehydroxylation and crystallization effects, reaching a steady stage after
40 h treatment time. For biotite, the original single peak profile for the
dehydroxylation of the untreated sample is converted into a two peaks profile
after sonication, the intensity of the low temperature peak increases with
sonication time, while the intensity of the high temperature peak decreases.
The modification of the thermal behavior for sonicated samples has been
correlated to the particle size distribution effect produced by the sonication
treatment. It has been also observed that the cup tip of the sonication
equipment contaminates the samples releasing titanium of its compositio
A jade pished hand-axe from Tubino's Cection (Valencina de la Concepción Local Museum, Sevilla, Spain)
A pished axe donated to the Valencina de la Concepción Museum (Seville, Spain) in November 2010, and that had belonged to Francisco María Tubino y Oliva's (1833-1888) personal clection, is studied. Although the exact provenance of this object is unknown, there are reasons to think that it might have been found on some archaẽogical site of the Seville province. Through the application of two different analytical techniques (XRD, DCμRS), this axe is identified as a jade-jadeite of purity above 95 ml%, which necessarily implies it came from the Alps. In the conclusions a discussion of this artifact is made in terms of long distance contact in Iberian Late Prehistory.Peer Reviewe
Do the Spanish university students follow Mediterranean dietary patterns?
Objetivo: Determinar el patrón de consumo de alimentos del alumnado de la Universidad de Alicante (UA) mediante el grado de adecuación a la dieta mediterránea. Método: Estudio transversal descriptivo para estimar la ingesta individual a través de un cuestionario de frecuencia de consumo de alimentos (CFCA) en una muestra representativa de 380 universitarios. Variables a estudio: edad, sexo, área geográfica de procedencia, peso y talla autoreferidos. Así como los alimentos y frecuencias de consumo que componen el CFCA. Se determinó el porcentaje de adecuación teniendo en cuenta, consumo real sobre consumo recomendado por la guía dieta mediterránea tradicional: (100 x raciones consumidas/raciones recomendadas). Se establecieron 5 rangos de porcentaje adecuación: consumo óptimo (80%-119%), consumo aceptable (60%-79%), consumo deficiente (40%-59%), consumo muy deficiente ( 120%). Se realizó contraste de diferencia de proporciones y la prueba t-Student con EPIDAT 3.1, y SPSS 15.0. Resultados: Prevalencia de sobrepeso-obesidad, es mayor en hombres (34,6%) que en mujeres (9,8%), p 120%). We analyzed the differences in proportions distribution and the Student’s t test with EPIDAT 3.1 and SPSS 15.0. Results: The prevalence of overweight/obesity is higher in men (34.6%) than in women (9.8%), p < 0.001, whereas women had higher prevalence of low weight (7.0%) than men (0.7%), p < 0.05. The consumption of grains and derivatives was very deficient (women = 90.6; men = 94.9) whereas the intake of red meats (women = 90.6; men = 92.7) and cold meats (women = 95.9%, men = 96.3%) was excessive. No student had an “optimal intake” or an “acceptable intake” of all the dietary groups (n = 12). Discussion: The educational level and access to the information do not protect the university population from socio-environmental factors that have an influence on their dietary habits. The public health strategies focused on this population group should be strengthen
Towards higher current and voltage LCLs
LCLs are widely used devices for power control
and distribution in satellites. Traditionally, P-type MOSFETs
have been used due to their simplicity from the control
perspective. Actual ESA standard defines LCLs up to class 10
(10A) and 50V. However, 100V bus voltage is common in high
power platforms and the current trend is to increase even more
this value, around 300V. In this new scenario, the classic concept
of LCL design needs to be revised, and this work proposes a
simple alternative for P-type MOSFETs that operates at high
voltage and can be easily scaled up in curren
Functional requirements to mitigate the Risk of Harm to Patients from Artificial Intelligence in Healthcare
The Directorate General for Parliamentary Research Services of the European
Parliament has prepared a report to the Members of the European Parliament
where they enumerate seven main risks of Artificial Intelligence (AI) in
medicine and healthcare: patient harm due to AI errors, misuse of medical AI
tools, bias in AI and the perpetuation of existing inequities, lack of
transparency, privacy and security issues, gaps in accountability, and
obstacles in implementation.
In this study, we propose fourteen functional requirements that AI systems
may implement to reduce the risks associated with their medical purpose: AI
passport, User management, Regulation check, Academic use only disclaimer, data
quality assessment, Clinicians double check, Continuous performance evaluation,
Audit trail, Continuous usability test, Review of retrospective/simulated
cases, Bias check, eXplainable AI, Encryption and use of field-tested
libraries, and Semantic interoperability.
Our intention here is to provide specific high-level specifications of
technical solutions to ensure continuous good performance and use of AI systems
to benefit patients in compliance with the future EU regulatory framework.Comment: 14 pages, 1 figure, 1 tabl
Deterioro de aleaciones de cobre por acción humana
7 pages, 8 figures. --Technical note.[EN] Results are presented from several samples taken from leaves of the Pardon Portico of Mosque-Cathedral of Cordoba,
where an alteration on their surface was detected. Metal samples analyzed using X-ray microanalysis and powder xray
diffraction were predominantly constituted by copper with some amounts of zinc attributed to brass, whereas other
samples were also constituted by copper, tin and lead attributed to bronze. Surface samples were analyzed using
the same techniques. In addition Fourier transform infrared spectroscopy was also used.The main compound identified
in all the surface of the leaves is copper chloride hydroxide (atacamite). Lead chlorides have also been found.
These data show that the sudden alteration that appears may be attributed to the use of some cleaning product
containing chloride. Other compounds detected in the surface were gypsum, quartz and oxalates coming from environmental
contamination.[ES] Se exponen los resultados de algunas muestras alteradas procedentes de la Puerta del Perdón, pertenecientes a la
Mezquita de Córdoba. Algunas de las muestras de metal analizadas mediante difracción de rayos X y microanálisis
por energía dispersiva de rayos X estaban constituidas por latón (cobre con pequeñas cantidades de zinc), mientras
que otras estaban constituidas por bronce (cobre, estaño y plomo). La superficie de las muestras se analizó empleando
las mismas técnicas. Asimismo, se usó espectroscopia de infrarrojos. El componente principal identificado en la
superficie de la puerta es cloruro básico de cobre (atacamita). Además se han encontrado cloruros de plomo.
Estos datos demuestran que la repentina alteración de la superficie se puede atribuir al uso de productos de limpieza
con alto contenido en cloro. Otros compuestos procedentes de la contaminación externa, como yeso, cuarzo y
oxalatos también se detectaron en la superficie.Peer reviewe
Study of mixing process of low temperature co-fired ceramics photocurable suspension for digital light processing stereolithography
The Low Temperature Co-fired Ceramic (LTCC) materials are highly used for high frequency devices required for high-speed data communications, representing an attractive material for electronic applications with a direct industrial applicability. The development of a photocurable LTCC suspension for Digital Light Processing Stereolithography (DLP-SLA) technology is presented in this work. The LTCC suspension, with an optimal solid load of 40.4 vol%, was characterized along its preparation regarding the rheological behaviour, dispersant content, particle size distribution in function of milling time and photocuring properties in a visible light range. The effect of the particle size change, through ball milling, on viscosity and photocuring behaviour was studied, achieving an optimal mixing range time, which highlights the importance of the manufacturing standardization of the photocurable suspensions. The optimized suspension presents a viscosity of 3.6 Pa s at shear rate of 2 s−1, a sensitivity of 41 μm and a critical energy dose of 15 mJ cm−2. The printing process was successfully achieved, demonstrated by some defect-free printed pieces
CVS-Q teen©: computer vision syndrome in adolescents and its relationship with digital textbooks
Objetivo: Analizar la prevalencia y la evolución del síndrome visual informático en estudiantes de secundaria y bachillerato mediante el CVS-Q© adaptado y validado para adolescentes, según empleen libros en papel o en soporte digital. Método: Se adaptará el CVS-Q© mediante un pilotaje en adolescentes y un grupo nominal compuesto por especialistas en salud visual, profesorado y padres/madres. Se evaluarán la calidad y la aplicabilidad de la versión resultante (CVS-Q teen©) y se realizará un estudio de validación con pruebas visuales, retest y análisis psicométrico. Posteriormente, se realizará un estudio prospectivo longitudinal con cuatro medidas repetidas en adolescentes de dos institutos de San Juan de Alicante (uno ha sustituido libros por tabletas). Se medirá el síndrome visual informático mediante el CVS-Q teen© con tres seguimientos. Se analizará la prevalencia de síndrome visual informático según factores sociodemográficos, visuales y de uso de dispositivos digitales. Se realizarán modelos de regresión logística con efecto aleatorio por estudiante y tiempo de uso.Objective: To analyse the prevalence and progression of computer vision syndrome in secondary and high school students with the CVS-Q© adapted and validated for adolescents, depending on whether they use textbooks or digital books. Method: The CVS-Q© will be adapted by a pilot study in adolescents and a nominal group of visual health specialists, teachers and parents. The resulting version (CVS-Q teen©) will be tested to confirm its quality and applicability and a validation study will be done with visual tests, retest and psychometric analysis. Subsequently, a prospective longitudinal study with four repeated measures will be carried out in adolescents from two secondary schools of San Juan de Alicante (one has replaced textbooks by tablets). Computer vision syndrome will be measured by the CVS-Q teen© with three follow-ups. The prevalence of computer vision syndrome will be analysed according to sociodemographic, visual and digital device use variables. Logistic regression models will be performed, with random effect by student and time of use.Los autores agradecen al Vicerrectorado de Investigación de la Universidad de Alicante por el contrato de formación predoctoral de la segunda autora (UAFPU2019-08). El presente proyecto ha sido financiado por la convocatoria «Proyectos de Investigación en Salud», Fondo de Investigación en Salud del Instituto de Salud Carlos III, Ministerio de Ciencia e Innovación y Unión Europea, a través de los Fondos Europeos de Desarrollo Regional (FEDER) «Una manera de hacer Europa», con la referencia PI20/01629
- …