From Josephson junction metamaterials to tunable pseudo-cavities

arXiv:1305.4844v1The scattering through a Josephson junction (JJ) interrupting a superconducting line is revisited including power leakage. We also discuss how to make tunable and broadband resonant mirrors by concatenating junctions. As an application, we show how to construct cavities using these mirrors, thus connecting two research fields: JJ quantum metamaterials and coupled-cavity arrays. We finish by discussing the first nonlinear corrections to the scattering and their measurable effects. © 2013 IOP Publishing Ltd.This work was supported by Spanish government projects FIS2009-10061, and FIS2011-25167 conanced by FEDER funds. We thanks Aragon government support to group FENOL, CAM research consortium QUITEMAD and PROMISCE European project.Peer Reviewe

Setups microfluídicos dedicados al cultivo celular

El desarrollo de nuevas herramientas de cultivo celular basadas en microtecnologías permitecontrolar el escenario mecánico, químico y eléctrico de las muestras biológicas, así comomonitorizar sus reacciones de una manera que hasta ahora era imposible. Como consecuencia,es posible generar nuevas vías para la realización de tests “in-vitro” en condiciones muysimilares a las “in-vivo”. Se espera que dicho avance permita reducir la experimentación conanimales y optimizar el desarrollo de nuevos fármacos a través de pruebas de test masivo (highthroughput).Hasta la fecha, los dispositivos microfluídicos para cultivo celular han estado basados entecnología de litografía blanda (soft-lithography), utilizando materiales como el PDMS. Latecnología basada en el material polimérico SU-8 ha sido ya previamente desarrollada y testeadapara aplicaciones del diagnóstico clínico, permitiendo no solo la construcción robusta demicrocanales, sino la posibilidad de integrar sensores y de crear redes de canales en tresdimensiones entre otras características interesantes.Tras la fabricación de los primeros dispositivos microfluídicos en SU-8 y la realización de lainserción de células en su interior, se ha podido corroborar la viabilidad del crecimiento celularen dichos dispositivos, aplicando un flujo de nutrientes continuo y controlado. Este control deflujo y el ambiente biomimético buscado se consiguen mediante el establecimiento de todo unsetup microfluídico consistente en encapsulado para el chip, reservorio, válvulas y microbomba.En este tipo de experimentación es muy importante tener un control preciso del flujo que se leestá aplicando a las células, por lo que el control de la microbomba es uno de los aspectosfundamentales en el desarrollo de setup microfluídicos para cultivo celular

Comparison of four functionalization methods of gold nanoparticles for enhancing the enzyme-linked immunosorbent assay (ELISA)

The enzyme-linked immunosorbent assay (ELISA) technique is based on the specific recognition ability of the molecular structure of an antigen (epitope) by an antibody and is likely the most important diagnostic technique used today in bioscience. With this methodology, it is possible to diagnose illness, allergies, alimentary fraud, and even to detect small molecules such as toxins, pesticides, heavy metals, etc. For this reason, any procedures that improve the detection limit, sensitivity or reduce the analysis time could have an important impact in several fields. In this respect, many methods have been developed for improving the technique, ranging from fluorescence substrates to methods for increasing the number of enzyme molecules involved in the detection such as the biotin–streptavidin method. In this context, nanotechnology has offered a significant number of proposed solutions, mainly based on the functionalization of nanoparticles from gold to carbon which could be used as antibody carriers as well as reporter enzymes like peroxidase. However, few works have focused on the study of best practices for nanoparticle functionalization for ELISA enhancement. In this work, we use 20 nm gold nanoparticles (AuNPs) as a vehicle for secondary antibodies and peroxidase (HRP). The design of experiments technique (DOE) and four different methods for biomolecule loading were compared using a rabbit IgG/goat anti-rabbit IgG ELISA model (adsorption, directional, covalent and a combination thereof). As a result, AuNP probes prepared by direct adsorption were the most effective method. AuNPs probes were then used to detect gliadin, one of the main components of wheat gluten, the protein composite that causes celiac disease. With this optimized approach, our data showed a sensitivity increase of at least five times and a lower detection limit with respect to a standard ELISA of at least three times. Additionally, the assay time was remarkably decreased.The authors would like to thank the Government of Navarra, Department of Innovation, Business and Employment for financial support within the project SABioD

Assessment of vapor pressure deficit variability and trends in Spain and possible connections with soil moisture

The Vapor Pressure Deficit (VPD) is one of the most relevant surface meteorological variables; with important implications in ecology, hydrology, and atmosphere. By understanding the processes involved in the variability and trend of the VPD, it is possible to assess the possible impacts and implications related to both physical and human environments, like plant function, water use efficiency, net ecosystem production, atmospheric CO2 growth rate, etc. This study analysed recent temporal variability and trends in VPD in Spain between 1980 and 2020 using a recently developed high-quality dataset. Also, the connection between VPD and soil moisture and other key climate variables (e.g. air temperature, precipitation, and relative humidity) was assessed on different time scales varying from weekly to annual. The objective was to determine if changes in land-atmosphere feedbacks connected with soil moisture and evapotranspiration anomalies have been relevant to assess the interannual variability and trends in VPD. Results demonstrate that VPD exhibited a clear seasonality and dominant positive trends on both the seasonal (mainly spring and summer) and annual scales. Rather, trends were statistically non-significant (p > 0.05) during winter and autumn. Spatially, VPD positive trends were more pronounced in southern and eastern of Spain. Also, results suggest that recent trends of VPD shows low contribution of variables that drive land-atmosphere feedbacks (e.g. evapotranspiration, and soil moisture) in comparison to the role of global warming processes. Notably, the variability of VPD seems to be less coupled with soil moisture variability during summertime, while it is better interrelated during winter, indicating that VPD variability would be mostly related to climate variability mechanisms that control temperature and relative humidity than to land-atmosohere feedbacks. Overall, our findings highlight the importance of assessing driving forces and physical mechanisms that control VPD variability using high-quality climate datasets, especially, in semiarid and sub-humid regions of the world

A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

Meeting abstrac

The behavior of mixed-metal oxides: Physical and chemical properties of bulk Ce1–xTbxO2 and nanoparticles of Ce1–xTbxOy

11 pages, 12 figures, 3 tables.-- PACS: 61.46.+w; 61.72.Ji; 78.70.Dm; 78.30.Hv; 71.15.Mb; 64.75.+g; 82.65.+rThe physical and chemical properties of bulk Ce1–xTbxO2 and Ce1–xTbxOy nanoparticles (x<0.5) were investigated using synchrotron-based x-ray diffraction (XRD), x-ray adsorption near edge spectroscopy (XANES), Raman spectroscopy (RS), and first-principles density-functional (DF) calculations. DF results and Raman spectra point to a small tetragonal distortion after introducing terbium in ceria. The results of XRD show a small contraction ( <0.08 Å) in the cell dimensions. The presence of Tb generates strain in the lattice through the variation of the ionic radii and creation of crystal imperfections and O vacancies. The strain increases with the content of Tb and affects the chemical reactivity of the Ce1–xTbxOy nanoparticles towards hydrogen, SO2, and NO2. DF calculations for bulk Ce1–xTbxO2 and Ce8–nTbnO16 (n = 0, 1, 2, or 4) clusters show oxide systems that are not fully ionic. The theoretical results and XANES spectra indicate that neither a CeTb exchange nor the introduction of oxygen vacancies in Ce1–xTbxOy significantly affect the charge on the Ce cations. In contrast, the O K-edge and Tb LIII-edge XANES spectra for Ce1–xTbxOy nanoparticles show substantial changes with respect to the corresponding spectra of Ce and Tb single oxide references. The Ce0.5Tb0.5Oy compounds exhibit a much larger Tb3+/Tb4+ ratio than TbO1.7. A comparison with the properties of Ce1–xZrxOy and Ce1–xCaxOy shows important differences in the charge distribution, the magnitude of the dopant induced strain in the oxide lattice, and a superior behavior in the case of the Ce1–xTbxOy systems. The Tb-containing oxides combine stability at high temperature against phase segregation and a reasonable concentration of O vacancies, making them attractive for chemical and catalytic applications.The research carried out at the Chemistry Department of Brookhaven National Laboratory was financed through Contract No. DE-AC02-98CH10086 with the U.S. Department of Energy (Division of Chemical Sciences). The NSLS and APS are supported by the Divisions of Materials and Chemical Sciences of DOE. Work at the ‘‘Instituto de Catálisis (CSIC)’’ was done with financial support from CICYT (Contract No. MAT2000-1467).Peer reviewe

Volatile compounds in low-acid fermented sausage "espetec" and sliced cooked pork shoulder subjected to high pressure processing. A comparison of dynamic headspace and solid-phase microextraction

Two extraction techniques, dynamic headspace extraction (DHE) and solid-phase microextraction (SPME), were compared to assess the effect of high-pressure treatment (400 MPa, 10 min, 12 °C) on the volatile compounds of low-acid fermented sausage "espetec" and sliced cooked pork shoulder stored at 4 °C. DHE was more efficient at extracting low-boiling compounds such as ethanal, 2,3-butanedione and alcohols, while SPME extracted more efficiently a higher number of chemical families, especially fatty acids. The effect of pressurisation on the volatile fraction of "espetec" was better categorized by DHE, whereas SPME was more appropriate for cooked pork shoulder. The volatile fraction of "espetec" changed slightly after pressurisation, mainly showing a decrease in the levels of lipid-derived compounds, like linear alkanes, aldehydes, or 1-alcohols in pressurised samples. The volatile profile of cooked pork shoulder underwent substantial changes during refrigerated storage, mainly due to microbial metabolism, most of these changes being limited by HPP. © 2011 Elsevier Ltd. All rights reserved

Volatile compounds in ground beef subjected to high pressure processing A comparison of dynamic headspace and solid-phase microextraction

The effect on the volatile profile of cooked beef meat, previously subjected to high pressure (400. MPa, 10. min at 12 °C) followed by a 3-d refrigerated storage, was investigated by comparing two extraction techniques i.e. dynamic headspace and solid-phase microextraction. Dynamic headspace was more efficient in extracting 2,3-butanedione and secondary alcohols. Solid-phase microextraction, being more efficient in extracting substances such as 1-alcanols, ethyl esters and acids, permitted to better categorize the effects caused in the volatile fraction by refrigerated storage and high pressure processing. The volatile fraction of cooked control beef meat contained high amounts of diketones and low amounts of methyl ketones, secondary alcohols, aldehydes and fatty acids. While diketones nearly disappeared after the 3-d refrigerated storage, the other compounds together with ethanol and ethyl esters increased significantly. Pressurized beef samples underwent fewer changes than non-pressurized samples during refrigerated storage, leading to a volatile profile closer to that of control beef. © 2010 Elsevier Ltd

Effects of high-pressure processing on the volatile compounds of sliced cooked pork shoulder during refrigerated storage

The effect of high-pressure processing (pressure levels of 400, 500 and 600. MPa, and exposure times of 5 and 10. min) on the volatile profile of vacuum-packaged sliced cooked pork shoulder held for 28. days at 4 °C was assessed. The volatile fraction of pressurized samples scarcely changed immediately after treatment and remained stable for 14. days, regardless the pressure and time of exposure. After 21. days of storage, significant differences were observed in the profile of volatile compounds in pressurized samples as compared with control samples, these differences being treatment dependent. At the end of the storage period, control and 400. MPa samples showed higher levels of acetic and fatty acids, ethanol and ethyl esters, whereas 500 and 600. MPa samples contained higher levels of ethanal, branched-chain aldehydes, diacetyl, acetoin, and 2,3-butanediol among other compounds. These results suggest that the high-pressure treatment had a discriminant effect on the microbiota of cooked pork shoulder, which led to the accumulation of different volatile compounds during the refrigerated storage of control and pressurized samples. © 2010 Elsevier Ltd