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1.
Sci Rep ; 11(1): 8176, 2021 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-33854183

RESUMEN

The functional properties of cuprates are strongly determined by the doping state and carrier density. We present an oxygen doping study of YBa2Cu3O7-δ (YBCO) thin films from underdoped to overdoped state, correlating the measured charge carrier density, [Formula: see text], the hole doping, p, and the critical current density, [Formula: see text]. Our results show experimental demonstration of strong increase of [Formula: see text] with [Formula: see text], up to Quantum Critical Point (QCP), due to an increase of the superconducting condensation energy. The ultra-high [Formula: see text] achieved, 90 MA cm-2 at 5 K corresponds to about a fifth of the depairing current, i.e. a value among the highest ever reported in YBCO films. The overdoped regime is confirmed by a sudden increase of [Formula: see text], associated to the reconstruction of the Fermi-surface at the QCP. Overdoping YBCO opens a promising route to extend the current carrying capabilities of rare-earth barium copper oxide (REBCO) coated conductors for applications.

2.
BMC Res Notes ; 13(1): 503, 2020 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-33138858

RESUMEN

OBJECTIVES: The Brown trout is a salmonid species with a high commercial value in Europe. Life history and spawning behaviour include resident (Salmo trutta m. fario) and migratory (Salmo trutta m. trutta) ecotypes. The main objective is to apply RNA-seq technology in order to obtain a reference transcriptome of two key tissues, brain and muscle, of the riverine trout Salmo trutta m. fario. Having a reference transcriptome of the resident form will complement genomic resources of salmonid species. DATA DESCRIPTION: We generate two cDNA libraries from pooled RNA samples, isolated from muscle and brain tissues of adult individuals of Salmo trutta m. fario, which were sequenced by Illumina technology. Raw reads were subjected to de-novo transcriptome assembly using Trinity, and coding regions were predicted by TransDecoder. A final set of 35,049 non-redundant ORF unigenes were annotated. Tissue differential expression analysis was evaluated by Cuffdiff. A False Discovery Rate (FDR) ≤ 0.01 was considered for significant differential expression, allowing to identify key differentially expressed unigenes. Finally, we have identified SNP variants that will be useful tools for population genomic studies.


Asunto(s)
Transcriptoma , Trucha , Animales , Encéfalo , Músculos , Transcriptoma/genética , Trucha/genética
3.
Rev Sci Instrum ; 89(11): 113301, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30501316

RESUMEN

Supersonic molecular beams are used in many applications ranging from spectroscopy and matter wave optics to surface science. The experimental setup typically includes a conically shaped, collimating aperture, the skimmer. It has been reported that microskimmers with diameters below 10 µm produce beams with significantly broader velocity distributions (smaller speed ratios) than larger skimmers. Various explanations for this phenomenon have been proposed, but up till now, only a limited amount of data has been available. Here we present a systematic study of the velocity distribution in microskimmer supersonic expansion helium beams. We compare a 4 µm diameter skimmer with a 390 µm diameter skimmer for room temperature and cooled beams in the pressure range 11-181 bars. Our measurements show that for properly aligned skimmers, the only difference is that the most probable velocity for a given pressure and temperature is slightly lower for a microskimmed beam. We ascribed this to the comparatively narrow and long geometry of the microskimmers which can lead to local pressure variations along the skimmer channel. We compare our measurements to a model for the supersonic expansion and obtain good agreement between the experiments and simulations.

4.
Sci Rep ; 8(1): 7064, 2018 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-29717188

RESUMEN

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

5.
Sci Rep ; 8(1): 5924, 2018 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-29651116

RESUMEN

The shape of the electric-field-current-density (E-J) curve is determined by flux pinning and also by dynamics of vortices. Here, we propose a novel methodology to study the normalized flux creep rate S in YBa2Cu3O7-δ measured from E-J curves obtained by electrical transport measurements that provides a fast and versatile way to foresee the flux magnetic relaxation in films and disentangle angular flux creep contributions by the scaling of the isotropic contribution of S. After a detailed comparison of various pristine and nanocomposite films with differentiated nanostructures, we focus on the roles that intrinsic pinning and stacking faults (YBa2Cu4O8-intergrowths) play when the magnetic field is applied parallel to the superconducting CuO2 planes. This study reveals that the emerging intergrowths provide advanced pinning properties that additionally reduce the thermal activated flux magnetic relaxation. For this purpose, creep analysis becomes a very appropriate tool to elucidate the dominance of the different pinning sites at different regions of the magnetic-field-temperature diagram.

6.
Sci Rep ; 7(1): 5663, 2017 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-28720833

RESUMEN

Superconductivity and ferromagnetism are two antagonistic phenomena that combined can lead to a rich phenomenology of interactions, resulting in novel physical properties and unique functionalities. Here we propose an original hybrid system formed by a high-temperature superconducting film, patterned with antidots, and with ferromagnetic nano-rods grown inside them. This particular structure exhibits the synergic influence of superconductor (SC) - ferromagnetic (FM) stray fields, in both the superconducting behaviour of the film and the three-dimensional (3D) magnetic structure of nano-rods. We show that FM stray fields directly influence the critical current density of the superconducting film. Additional functionalities appear due to the interaction of SC stray fields, associated to supercurrent loops, with the non-trivial 3D remanent magnetic structure of FM nano-rods. This work unravels the importance of addressing quantitatively the effect of stray magnetic fields from both, the superconductor and the ferromagnet in hybrid magnetic nano-devices based on high temperature superconductors.

7.
Phys Chem Chem Phys ; 19(21): 14129-14140, 2017 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-28524207

RESUMEN

The kinetics of oxygen incorporation (in-diffusion process) and excorporation (out-diffusion process), in YBa2Cu3O6+x (YBCO) epitaxial thin films prepared using the chemical solution deposition (CSD) methodology by the trifluoroacetate route, was investigated by electrical conductivity relaxation measurements. We show that the oxygenation kinetics of YBCO films is limited by the surface exchange process of oxygen molecules prior to bulk diffusion into the films. The analysis of the temperature and oxygen partial pressure influence on the oxygenation kinetics has drawn a consistent picture of the oxygen surface exchange process enabling us to define the most likely rate determining step. We have also established a strategy to accelerate the oxygenation kinetics at low temperatures based on the catalytic influence of Ag coatings thus allowing us to decrease the oxygenation temperature in the YBCO thin films.

8.
Rev Sci Instrum ; 87(2): 023102, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26931829

RESUMEN

Time-of-flight (TOF) is a standard experimental technique for determining, among others, the speed ratio S (velocity spread) of a molecular beam. The speed ratio is a measure for the monochromaticity of the beam and an accurate determination of S is crucial for various applications, for example, for characterising chromatic aberrations in focussing experiments related to helium microscopy or for precise measurements of surface phonons and surface structures in molecular beam scattering experiments. For both of these applications, it is desirable to have as high a speed ratio as possible. Molecular beam TOF measurements are typically performed by chopping the beam using a rotating chopper with one or more slit openings. The TOF spectra are evaluated using a standard deconvolution method. However, for higher speed ratios, this method is very sensitive to errors related to the determination of the slit width and the beam diameter. The exact sensitivity depends on the beam diameter, the number of slits, the chopper radius, and the chopper rotation frequency. We present a modified method suitable for the evaluation of TOF measurements of high speed ratio beams. The modified method is based on a systematic variation of the chopper convolution parameters so that a set of independent measurements that can be fitted with an appropriate function are obtained. We show that with this modified method, it is possible to reduce the error by typically one order of magnitude compared to the standard method.

9.
Physiol Meas ; 37(1): 128-44, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26657196

RESUMEN

This work proposes a systematic procedure to report the differences between heart rate variability time series obtained from alternative measurements reporting the spread and mean of the differences as well as the agreement between measuring procedures and quantifying how stationary, random and normal the differences between alternative measurements are. A description of the complete automatic procedure to obtain a differences time series (DTS) from two alternative methods, a proposal of a battery of statistical tests, and a set of statistical indicators to better describe the differences in RR interval estimation are also provided. Results show that the spread and agreement depend on the choice of alternative measurements and that the DTS cannot be considered generally as a white or as a normally distributed process. Nevertheless, in controlled measurements the DTS can be considered as a stationary process.


Asunto(s)
Pruebas de Función Cardíaca/métodos , Frecuencia Cardíaca , Electrocardiografía , Factores de Tiempo
10.
Sci Total Environ ; 540: 144-57, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26188652

RESUMEN

This paper assesses annual and seasonal trends in runoff and sediment load resulting from climate variability and afforestation in an upland Mediterranean basin, the Ribera Salada (NE Iberian Peninsula). We implemented a hydrological and sediment transport distributed model (TETIS) with a daily time-step, using continuous discharge and sediment transport data collected at a monitoring station during the period 2009-2013. Once calibrated and validated, the model was used to simulate the hydrosedimentary response of the basin for the period 1971-2014 using historical climate and land use data. Simulated series were further used to (i) detect sediment transport and hydrologic trends at different temporal scales (annual, seasonal); (ii) assess changes in the contribution of extreme events (i.e. low and high flows) and (ii) assess the relative effect of forest expansion and climate variability on trends observed by applying a scenario of constant land use. The non-parametric Mann-Kendall test indicated upward trends for temperature and decreasing trends (although non-significant) for precipitation. Downward trends occurred for annual runoff, and less significantly for sediment yield. Reductions in runoff were less intense when afforestation was not considered in the model, while trends in sediment yield were reversed. Results also indicated that an increase in the river's torrential behaviour may have occurred throughout the studied period, with low and high flow events gaining importance with respect to the annual contribution, although its magnitude was reduced over time.

11.
Allergol. immunopatol ; 43(3): 286-291, mayo-jun. 2015. tab, ilus
Artículo en Inglés | IBECS | ID: ibc-136336

RESUMEN

INTRODUCTION: Anaphylaxis is the most severe of all allergic reactions and can even prove fatal. There is limited evidence of a difference in prescribing patterns for self-injectable epinephrine (SIE) between general paediatricians and paediatricians with greater knowledge of allergology. OBJECTIVES: Assess knowledge about prescribing SIE of a sample of primary care/hospital paediatricians and paediatricians with specialised knowledge of allergology through a questionnaire asking them about clinical cases of anaphylaxis in their daily paediatric practice. MATERIALS AND METHODS: Participants were primary care and hospital paediatricians practicing in different regions of the province of Barcelona and paediatricians with specialised knowledge in the field of allergology from Spain. RESULTS: A total of 183 paediatricians responded. Of that 59.6% were paediatricians with specialised knowledge of allergology. General paediatricians in most cases correctly prescribed SIE device (more than 70% answered correctly in five of the eight clinical cases). In the case of drug anaphylaxis, which is an avoidable allergen for which SIE is not indicated, 67.5% of general paediatricians would prescribe it. In the case of exercise-induced anaphylaxis there were also differences in the prescription of epinephrine by general paediatricians, with only 40% prescribing it. CONCLUSIONS: In this study the percentage of SIE prescriptions would be higher than expected by general paediatricians, with no differences in the cases proposed between them and the paediatricians with better knowledge of allergology. Despite these results, it is important to insist on conducting education programmes and disseminating them to facilitate physicians' recognition and treatment of anaphylactic reactions


No disponible


Asunto(s)
Humanos , Masculino , Femenino , Utilización de Medicamentos/ética , Utilización de Medicamentos/normas , Epinefrina/inmunología , Epinefrina/metabolismo , Epinefrina/uso terapéutico , Automedicación/métodos , Atención Hospitalaria , Alergia e Inmunología/educación , Alergia e Inmunología , Alergia e Inmunología/organización & administración , Anafilaxia/epidemiología , Anafilaxia/inmunología , Pediatría , Encuestas y Cuestionarios
13.
Allergol Immunopathol (Madr) ; 43(3): 286-91, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25097023

RESUMEN

INTRODUCTION: Anaphylaxis is the most severe of all allergic reactions and can even prove fatal. There is limited evidence of a difference in prescribing patterns for self-injectable epinephrine (SIE) between general paediatricians and paediatricians with greater knowledge of allergology. OBJECTIVES: Assess knowledge about prescribing SIE of a sample of primary care/hospital paediatricians and paediatricians with specialised knowledge of allergology through a questionnaire asking them about clinical cases of anaphylaxis in their daily paediatric practice. MATERIALS AND METHODS: Participants were primary care and hospital paediatricians practicing in different regions of the province of Barcelona and paediatricians with specialised knowledge in the field of allergology from Spain. RESULTS: A total of 183 paediatricians responded. Of that 59.6% were paediatricians with specialised knowledge of allergology. General paediatricians in most cases correctly prescribed SIE device (more than 70% answered correctly in five of the eight clinical cases). In the case of drug anaphylaxis, which is an avoidable allergen for which SIE is not indicated, 67.5% of general paediatricians would prescribe it. In the case of exercise-induced anaphylaxis there were also differences in the prescription of epinephrine by general paediatricians, with only 40% prescribing it. CONCLUSIONS: In this study the percentage of SIE prescriptions would be higher than expected by general paediatricians, with no differences in the cases proposed between them and the paediatricians with better knowledge of allergology. Despite these results, it is important to insist on conducting education programmes and disseminating them to facilitate physicians' recognition and treatment of anaphylactic reactions.


Asunto(s)
Alergia e Inmunología , Anafilaxia/epidemiología , Competencia Clínica/estadística & datos numéricos , Hipersensibilidad/epidemiología , Pautas de la Práctica en Medicina/estadística & datos numéricos , Anafilaxia/etiología , Anafilaxia/prevención & control , Epinefrina/administración & dosificación , Hospitales Especializados , Humanos , Hipersensibilidad/complicaciones , Hipersensibilidad/tratamiento farmacológico , Difusión de la Información , Pediatría , Médicos/estadística & datos numéricos , Atención Primaria de Salud , Autoadministración , España
16.
Euro Surveill ; 18(33): 20560, 2013 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-23968876

RESUMEN

Between January 2012 and June 2013, 27 sexually transmitted infections were reported in adolescents aged 13-15 years in Catalonia, Spain. In the first half of 2013, there were nine cases of gonorrhoea, while in the same period of 2012, there was one. In June 2013, two gonorrhoea cases aged 13-14 years, linked to a common source through a social network, were reported. The public health response should be adapted to this vulnerable population.


Asunto(s)
Gonorrea/epidemiología , Adolescente , Conducta del Adolescente , Distribución por Edad , Femenino , Gonorrea/microbiología , Humanos , Incidencia , Masculino , Vigilancia de la Población , Salud Pública , Conducta Sexual , España/epidemiología
18.
Nat Mater ; 11(4): 329-36, 2012 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-22327747

RESUMEN

Boosting large-scale superconductor applications require nanostructured conductors with artificial pinning centres immobilizing quantized vortices at high temperature and magnetic fields. Here we demonstrate a highly effective mechanism of artificial pinning centres in solution-derived high-temperature superconductor nanocomposites through generation of nanostrained regions where Cooper pair formation is suppressed. The nanostrained regions identified from transmission electron microscopy devise a very high concentration of partial dislocations associated with intergrowths generated between the randomly oriented nanodots and the epitaxial YBa(2)Cu(3)O(7) matrix. Consequently, an outstanding vortex-pinning enhancement correlated to the nanostrain is demonstrated for four types of randomly oriented nanodot, and a unique evolution towards an isotropic vortex-pinning behaviour, even in the effective anisotropy, is achieved as the nanostrain turns isotropic. We suggest a new vortex-pinning mechanism based on the bond-contraction pairing model, where pair formation is quenched under tensile strain, forming new and effective core-pinning regions.

20.
Rev Esp Sanid Penit ; 13(1): 15-20, 2011.
Artículo en Español | MEDLINE | ID: mdl-21484074

RESUMEN

OBJECTIVE: To study the agreement of Tuberculin Skin Tests (TST) and Interferon Gamma Release Assays (IGRA) when screening tuberculosis infection amongst inmates recently admitted to prison. MATERIALS AND METHODS: Prospective study conducted in a prison during the months of May and June 2009. Inmates without a TB history, with previous TST negatives or without prior TSTs were included. Participants signed an informed consent form and the study was approved by an independent Ethical Committee. TST (positive 10 > or = mm) and IGRA (Quantiferon TB-Gold) were performed and standardized data collection was carried out. The agreement between both tests was analysed using the Kappa index. RESULTS: A total of 181 people were included. 62% were foreign-born, 17% had previous BCG vaccination, 8.4% were IDUs and 4% HIV-infected. Foreign born subjects were more frequently vaccinated and presented less drug use and HIV infection than people born in Spain. (p=0.02, p=0.02 and p=0.01 respectively). TST results were positive in 24% and IGRA in 26%. Both tests were performed in 149 people (82%). Discordant results were observed in 15.8%. Agreement of the Kappa coefficient was 0.6 (CI 0.4-0.7). Agreement was better in the native population (K=0.8) and worse in BCG vaccinated (K=0.4) and foreign-born subjects (K=0.8). CONCLUSION: Overall agreement was moderate and was less amongst vaccinated subjects and those born abroad. Extension of the study could be useful to evaluate which test better predicts the risk of progression to active TB and the cost-benefit of both tests among the prison population.


Asunto(s)
Interferón gamma/sangre , Prisioneros , Prueba de Tuberculina , Tuberculosis/sangre , Tuberculosis/diagnóstico , Adulto , Anciano , Estudios Transversales , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Adulto Joven
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