2,391 research outputs found
Spherical nematics with a threefold valence
We present a theoretical study of the energetics of thin nematic shells with
two charge one-half defects and one charge-one defect. We determine the optimal
arrangement: the defects are located on a great circle at the vertices of an
isosceles triangle with angles of 66 degrees at the charge one-half defects and
a distinct angle of 48 degrees, consistent with experimental findings. We also
analyse thermal fluctuations around this ground state and estimate the energy
as a function of thickness. We find that the energy of the three-defect shell
is close to the energy of other known configurations having two charge-one and
four charge one-half defects. This finding, together with the large energy
barriers separating one configuration from the others, explains their
observation in experiments as well as their long-time stability.Comment: 8 pages, 7 figure
Staple-based paper electrochemical platform for celiac disease diagnosis
A staple-based electrochemical platform is proposed for the first time as a simple and low-cost detection system for paper-based devices. The system, that incorporates small and disposable stainless-steel staples as electrodes (modified with carbon ink in the case of the working electrode) is combined with a paper strip and is carefully optimized with ferrocene carboxylic acid. As a proof-of-concept, it was employed for the enzymatic (HRP-based) immunoelectroanalytical detection of human tissue anti-transglutaminase (anti-tTG), biomarker for celiac disease diagnosis. The intensity of the current due to the electrochemical reduction of TMB (HRP substrate) was recorded chronoamperometrically at -0.2 V in different paper areas. A linear relationship between the current measured at 30 s and the logarithm of the concentration of anti-tTG in the range comprised between 3 and 100 U.mL-1 was obtained. Negative and positive controls produced expected values. Results demonstrated that the paper/staple-combined platform is very convenient for the detection of electroactive analytes and other compounds that can be determined indirectly in bioassays.Fil: Nanni, Paula Inés. Universidad de Oviedo; España. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Bioingeniería. Laboratorio de Medios e Interfases; ArgentinaFil: Gonzalez Lopez, Andrea. Universidad de Oviedo; EspañaFil: Nuñez Bajo, Estefanía. Universidad de Oviedo; EspañaFil: Madrid, Rossana Elena. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Bioingeniería. Laboratorio de Medios e Interfases; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Investigaciones Biológicas. Universidad Nacional de Tucumán. Instituto Superior de Investigaciones Biológicas; ArgentinaFil: Fernandez Abedul, M. Teresa. Universidad de Oviedo; Españ
Bacterial Community Dynamics During the Application of a Myxococcus xanthus-Inoculated Culture Medium Used for Consolidation of Ornamental Limestone
In this study, we investigated under laboratory conditions the bacterial communities inhabiting quarry and decayed ornamental carbonate stones before and after the application of a Myxococcus xanthus-inoculated culture medium used for consolidation of the stones. The dynamics of the community structure and the prevalence of the inoculated bacterium, M. xanthus, were monitored during the time course of the consolidation treatment (30 days). For this purpose, we selected a molecular strategy combining fingerprinting by denaturing gradient gel electrophoresis (DGGE) with the screening of eubacterial 16S rDNA clone libraries by DGGE and sequencing. Quantification of the inoculated strain was performed by quantitative real-time PCR (qPCR) using M. xanthus-specific primers designed in this work. Results derived from DGGE and sequencing analysis showed that, irrespective of the origin of the stone, the same carbonatogenic microorganisms were activated by the application of a M. xanthus culture. Those microorganisms were Pseudomonas sp., Bacillus sp., and Brevibacillus sp. The monitoring of M. xanthus in the culture media of treated stones during the time course experiment showed disparate results depending on the applied technique. By culture-dependent methods, the detection of this bacterium was only possible in the first day of the treatment, showing the limitation of these conventional techniques. By PCR-DGGE analysis, M. xanthus was detected during the first 3–6 days of the experiment. At this time, the population of this bacterium in the culture media varied between 108–106 cells ml−1, as showed by qPCR analyses. Thereafter, DGGE analyses showed to be not suitable for the detection of M. xanthus in a mixed culture. Nevertheless, qPCR analysis using specific primers for M. xanthus showed to be a more sensitive technique for the detection of this bacterium, revealing a population of 104 cells ml−1 in the culture media of both treated stones at the end of the consolidation treatment. The molecular strategy used in this study is proposed as an effective monitoring system to evaluate the impact of the application of a bacterially induced carbonate mineralization as restoration/conservation treatment for ornamental stones
Electrochemical Detection for Isothermal Loop-Mediated Amplification of Pneumolysin Gene of Streptococcus pneumoniae Based on the Oxidation of Phenol Red Indicator
A highly sensitive electrochemical methodology for end-point detection of loop-mediated isothermal nucleic acid amplification reactions was developed. It is based on the oxidation process of phenol red (PR), commonly used as a visual indicator. The dependence of its redox process on pH, which changes during amplification, allows performing quantitative measurements. Thus, the change in the oxidation potential of PR during the amplification is used, for the first time, as the analytical signal that correlates with the number of initial DNA copies. As a proof-of-concept, the amplification of the pneumolysin gene from Streptococcus pneumoniae, one of the main pathogens causing community-acquired pneumonia, is performed. Combination of isothermal amplification with electrochemical detection, performed on small-size flexible electrodes, allows easy decentralization. Adaptation to the detection of other pathogens causing infectious diseases would be very useful in the prevention of future epidemics
Workshop on new strategies and tools for the eHealth library organized by the Andalusian eHealth Library
The Andalusian eHealth Library (Biblioteca Virtual del Sistema Sanitario Publico de Andalucia, BV-SSPA), was created in June 2006. The 42 librarians who already worked for the Health System were integrated within this new system. The annual library meeting has been held every year since then, and in 2013 the EAHIL workshop held in Stockholm was the model to follow
Mortalidad por causas esternas en España
En España se producen unas 14.000 muertes anuales por causas externas. Según datos de Eurostat 1, en el trienio 2008-2010 España tenía en hombres las tasas ajustadas de mortalidad por causas externas más bajas de los países de la Unión Europea, incluidos los de la Asociación Europea de Libre Comercio (EFTA), y en mujeres sólo Grecia presentaba tasas más bajas.
La mortalidad mayor por estas causas se encontraba en Lituania, con unas tasas que para uno y otro
sexo cuadruplicaban a las españolas, seguida de Letonia y Estonia.
Al hablar de mortalidad por causas externas nos referimos a la que tiene su origen en accidentes,
violencia, acontecimientos ambientales, envenenamientos y otros efectos adversos, tal como se recoge
en el Capítulo XX de la décima revisión de la Clasificación Internacional de Enfermedades (CIE) y en
los códigos «E» de revisiones anteriores 2. Cuando se produce un fallecimiento que obedezca o se sospeche que pueda ser debido a alguna de estas situaciones, es preceptiva la intervención judicial y la práctica de autopsia medicolegal para
determinar la causa y circunstancias de la muerte 3, 4. El secretario judicial es el responsable, a partir
del informe forense, de cumplimentar el Boletín Estadístico de Defunción Judicial (BEDJ) 5 (hasta 2009 era el documento MNP-52), que es el documento con finalidad estadística a partir del que se selecciona
la causa básica de defunción que se codifica de acuerdo con la CIE vigente para la elaboración, por
parte del Instituto Nacional de Estadística (INE), de la Estadística de Defunciones según la Causa de
Muerte 6. En estos casos se considera como causa básica de defunción el acontecimiento que origina
las lesiones que conducen a la muerte, siguiendo las normas de la Organización Mundial de la Salud.
Dentro de este grupo tenemos una variedad de causas que de acuerdo con la CIE se pueden
clasificar en intencionales (suicidio y homicidio), no intencionales (accidentes, ya sean de tráfico o de
cualquier otro tipo, incluyendo las causas de iatrogenia) y de intención indeterminada. Los accidentes
laborales mortales no se pueden diferenciar por la configuración de las CIE. Según las fuentes
específicas, la mortalidad por accidentes laborales de causa traumática vendría a suponer alrededor
de un 11% de todas las defunciones de causa externa no intencional en las edades productivas 7, 8. Las
causas de intención indeterminada en España supusieron en el período 2007-2011 solo un 0,6% de todas las externas, porcentaje muy inferior al de otros países. Así, en la unión europea, como media en el trienio 2008-2010 significaron el 5,1%, aunque con grandes variaciones, presentando los porcentajes más bajos los países mediterráneos, y los más altos los del este y, principalmente y a bastante distancia, Portugal (25%) 9. En algunos países, una mayoría de fallecimientos así clasificados responden a la sospecha de que pueda tratarse de algunas causas como homicidio y principalmente
suicidio, pero cuya intencionalidad no queda absolutamente clara.N
Rural-urban gradients and all-cause, cardiovascular and cancer mortality in Spain using individual data
The literature reporting on rural-urban health status disparities remains inconclusive. We analyzed data from a longitudinal population-based study using individual observations. Our results show that the risks of all-cause and cancer mortality are greater in large cities than in other municipalities, with no clear urban-rural gradient. Not differences were found among territories in cardiovascular mortality.This work was supported by the Institute of Health Carlos III (ISCIII), Ministry of Science and Innovation [grant number PI19CIII/00021 and FI17CIII/00003].S
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