Self-Referenced Multifrequency Phase-Resolved Luminescence Spectroscopy

Phase-resolved luminescence chemical sensors provide the analyte determination based on the estimation of the luminescence lifetime. The lifetime is estimated from an analysis of the amplitudes and/or phases of the excitation and emission signals at one or several modulation frequencies. This requires recording both the excitation signal (used to modulate the light source) and the emission signal (obtained from an optical transducer illuminated by the luminescent sensing phase). The excitation signal is conventionally used as reference, in order to obtain the modulation factor (the ratio between the emission and the excitation amplitudes) and/or the phase shift (the difference between the emission and the excitation phases) at each modulation frequency, which are used to estimate the luminescence lifetime. In this manuscript, we propose a new method providing the luminescence lifetimes (based either on amplitudes or phases) using only the emission signal (i.e., omitting the excitation signal in the procedure). We demonstrate that the luminescence lifetime can be derived from the emission signal when it contains at least two harmonics, because in this case the amplitude and phase of one of the harmonics can be used as reference. We present the theoretical formulation as well as an example of application to an oxygen measuring system. The proposed self-referenced lifetime estimation provides two practical advantages for luminescence chemical sensors. On one hand, it simplifies the instrument architecture, since only one analog-to-digital converter (for the emission signal) is necessary. On the other hand, the self-referenced estimation of the lifetime improves the robustness against degradation of the sensing phase or variations in the optical coupling, which reduces the recalibration requirements when the lifetimes are based on amplitudes.Spanish Ministry of Economy, Industry and Competitiveness CTQ2017-88079-P CTQ2014-53442-P BES-2009-026919Spanish Ministry of Economy, Industry and Competitiveness (Torres Quevedo Grants) PTQ-15-07922 PTQ-15-07912CEI BioTic Granada Campus CEIbioTIC14-201

A review of moisture diffusion coefficients in transformer solid insulation - Part 2: experimental validation of the coefficients

The objective of this article is to experimentally verify the diffusion coefficients proposed by the various researchers. To validate these coefficients, drying experiments were carried out on impregnated and nonimpregnated paper and on pressboard samples. Taking into account the characteristics of the tested samples, two different experiments were performed: For nonimpregnated insulation, thermo-gravimetric experiments were performed determining the weight of a sample while being dried. . For impregnated paper, drying experiments were carried out in hot oil in which samples were periodically extracted and analyzed by the Karl Fischer method. The drying experiments were simulated using a diffusion model, solved by finite element analysis. The simulations were carried out using the diffusion coefficients proposed by the various researchers. Finally, the experimental results were compared with the simulated ones, and the accuracy and the range of application of the various coefficients were determined.This work was financed by the Spanish Ministry of Science and Technology under the project DPI2009-07093Publicad

Assessing the use of natural esters for transformer field drying

In recent years, great attention has been paid to ester fluids as an alternative to mineral oil. Since the present use of these liquids is becoming a common practice in distribution transformers, even some experiences have been published reporting their application to power transformers. One of the main differences between ester fluid and mineral oil is the much greater capability of absorbing water by esters. In this paper, the possibility of using this kind of liquid in transformer field drying is assessed. Hot oil (HO) drying with mineral oil is one of the most widely used methods to dry transformers in the field, since it is a relatively simple and well-known process and it is less aggressive for the insulation than other drying methods. Moreover, drying the oil, while it is preferably hot, is the only method available to dry transformers online. However, the water extraction rate of the process is very poor because of the highly hydrophobic character of mineral oil and, in consequence, large drying times are needed to achieve a significant reduction in the water content of the insulation. A first theoretical analysis seems to indicate that the use of a less hydrophobic liquid would significantly reduce the drying times involved in the process. This paper aims to quantify the improvement of the HO drying process that is achieved by using ester fluids instead of mineral oil. Both drying agents were compared by means of theoretical simulations as well as laboratory tests.This work has been supported by the Spanish Government by means of the projects DPI2009-07093 and DPI2012-35819

Protease‐sensitive, VEGF‐mimetic peptide, and IKVAV laminin‐derived peptide sequences within elastin‐like recombinamer scaffolds provide spatiotemporally synchronized guidance of angiogenesis and neurogenesis

Producción CientíficaSpatiotemporal control of vascularization and innervation is a desiredhallmark in advanced tissue regeneration. For this purpose, we design a 3Dmodel scaffold, based on elastin-like recombinamer (ELR) hydrogels. Thiscontains two interior and well-defined areas, small cylinders, withdifferentiated bioactivities with respect to the bulk. Both are constructed on aprotease sensitive ELR with a fast-proteolyzed domain, but one bears aVEGF-mimetic peptide (QK) and the other a laminin-derived pentapeptide(IKVAV), to promote angiogenesis and neurogenesis, respectively. The outerbulk is based on a slow proteolytic sequence and RGD cell adhesion domains.In vitro studies show the effect of QK and IKVAV peptides on the promotion ofendothelial cell and axon spreading, respectively. The subcutaneousimplantation of the final 3D scaffold demonstrates the ability tospatiotemporally control angiogenesis and neurogenesis in vivo. Specifically,the inner small cylinder containing the QK peptide promotes fastendothelialization, whereas the one with IKVAV peptide promotes fastneurogenesis. Both, vascularization and innervation take place in advance ofthe bulk scaffold infiltration. This scaffold shows that it is possible to inducevascularization and innervation in predetermined areas of the scaffold wellahead to the bulk infiltration. That significantly increases the efficiency of theregenerative activity.Funding from the Spanish Government(Nos. RTI2018-096320-B-C22, FPU16-04015, PID2019-110709RB-I00, and PID2020-118669RA-I00)Interreg V España Portugal POCTEP (No.0624_2IQBIONEURO_6_E

Las nuevas enfermedades y la contaminación química.

Hace varios años, un grupo de prestigiosos científicos, entre los que se contaban varios galardonados con el Premio Nobel, suscribieron el Llamamiento de París, en el que advertían de que la contaminación química está produciendo una pandemia silenciosa, que contribuye, entre otras cosas, al crecimiento del cáncer, de la infertilidad y de problemas en el sistema hormonal o en el aparato respiratorio o nervioso. En el mismo sentido se han expresado otros manifiestos científicos como la Declaración de Praga, esta última centrada en las alteraciones endocrinas. El hombre ha creado más de 100.000 sustancias químicas sintéticas que no estaban presentes en la naturaleza, y sólo una mínima parte de ellas ha sido debidamente evaluada en cuanto a sus posibles riesgos para la salud humana y el medio ambiente.Peer Reviewe

Caracterización Proteómica del trombo coronario en pacientes con infarto agudo de miocardio con elevación del segmento ST

Comunicaciones a congreso

Effect of poultry manure and biosolid mixed with European turbe for cucurbit seedling production

En México, la turba de Sphagnum (peat moss), es el principal sustrato utilizado para la producción de plántulas de hortalizas en bandeja de poliestireno, su precio es elevado por ser de importación, lo que hace necesario estudiar alternativas de menor costo. Por lo anterior, se propone mezclar la turba con materiales orgánicos de origen local como la gallinaza (G) y biosólido (B) para producir plántulas de pepino (Cucumis sativus L.) y calabacita (Cucurbita pepo L.). Ocho mezclas de material orgánico-turba fueron evaluadas para cada especie: 1) 4% G + 96% turba; 2) 8% G + 92% turba; 3) 12% G + 88% turba; 4) 16% G + 84% turba; 5) 4% B + 96% turba; 6) 8% B + 92% turba; 7) 12% B + 88% turba; 8) 16% B + 84% turba, el tratamiento testigo fue 100% turba. En los resultados se destaca, en pepino, la mezcla con 16% de biosólido que afectó positivamente en unidades SPAD (Soil Plant Analysis Development), diámetro de tallo y área foliar, mientras que la mezcla con 12% de gallinaza aumentó peso seco de parte aérea y total (P ≤ 0,05). En calabacita, la mezcla con 16% de gallinaza incrementó área foliar (P ≤ 0,05). En las variables de altura, peso seco de raíz y balance de plántula no se encontraron diferencias significativas en ambas especies y mezclas. Se concluye que mezclas de turba europea (peat moss) con gallinaza o biosólido, son una importante alternativa técnica y económica para la producción de plántulas en pepino y calabacita.In Mexico, Sphagnum turbe (peat moss) is the main substrate used for the production of vegetable seedlings in polystyrene trays. It is imported and thus has an elevated price, therefore some lower cost alternatives need to be addressed. This work proposes a mixture of peat with local organic materials as poultry manure (PM) and biosolid (B) to produce cucumber (Cucumis sativus L.) and zucchini (Cucurbita pepo L.) seedlings. Eight mixtures of organic material-peat were evaluated for each species: 1) 4% PM + 96% peat; 2) 8% PM + 92% peat; 3) 12% PM + 88% peat; 4) 16% PM + 84% peat; 5) 4% B + 96% peat; 6) 8% B + 92% peat; 7) 12% B + 88% peat; 8) 16% B + 84% peat, and 100% peat as control. Compared with the control, the mixture with 16% of biosolid affected positively SPAD (Soil Plant Analysis Development) units, stem diameter and leaf area in cucumber seedlings, while the mixture with 12% of poultry manure increased aerial and total dry weight (P ≤ 0.05). In zucchini, the mixture with 16% of poultry manure increased leaf area (P ≤ 0.05). No significant differences were found in height, root dry weight and seedling balance in both species and mixtures. We concluded that use of peat moss mixed with poultry manure or biosolid represents an important technical and economic alternative for cucumber and zucchini seedling production.Fil: Carballo Méndez, Fernando de Jesús. Universidad Autónoma de San Luis Potosí. Facultad de AgronomíaFil: Rodríguez Ortiz, Juan Carlos. Universidad Autónoma de San Luis Potosí. Facultad de AgronomíaFil: García Hernández, José Luis.Fil: Alcalá Jáuregui, Jorge Alonso. Universidad Autónoma de San Luis Potosí. Facultad de AgronomíaFil: Preciado Rangel, Pablo. Instituto Tecnológico de Torreón (México)Fil: Rodríguez Fuentes, Humberto. Universidad Autónoma de Nuevo León (México). Facultad de Agronomía.Fil: Villarreal Guerrero, Federico. Universidad Autónoma de San Luis Potosí. Facultad de Agronomí

¿El emprendedor nace o se hace? Un análisis de los determinantes del espíritu emprendedor

Aún a sabiendas de que el espíritu emprendedor juega un papel clave como motor de la innovación y del bienestar en una economía, las cuestiones acerca de porqué se crean empresas y qué factores determinan tal hecho, es un fenómeno insuficientemente estudiado. En el presente trabajo, nuestro interés se centra en reconocer los factores determinantes del espíritu emprendedor. En concreto, se valoran las percepciones de una población de 2012 estudiantes universitarios que en el curso académico 2003/2004 se encontraba en los últimos años de sus estudios y su propensión a la creación de empresas. Utilizando un análisis de regresión logística binaria, se obtienen unos resultados que confirman las relaciones esperadas en relación con los determinantes de una orientación emprendedora: los hombres, con mayor formación y un mayor número de experiencias profesionales son los que tienen una orientación más emprendedora. Asimismo, las personas con mayor deseo de independencia y autoconfianza son las más que resultan más propensas a tomar decisiones empresariales.Although the entrepreneurship is basic as innovation device or as contributor for economic welfare, we do not much about why firms are created or which factors are determinants of new ventures. This paper tries to contribute to this subject exploring the factors related to the entrepreneurial direction of students. Particularly, we select a population of 2012 undergraduate students during the 2003/2004 academic year and we measure their entrepreneurial direction and the factors that motivate it. A logistic regression allows confirming the most of suggested relationships. The students who are entrepreneurshiporiented show a higher level of education, more professional experiences and they are usually men. Other than that, the self-reliant and self-confident individuals are the most prone to create a new venture

‘Long autonomy or long delay?’ The importance of domain in opinion mining

Nowadays, people do not only navigate the web, but they also contribute contents to the Internet. Among other things, they write their thoughts and opinions in review sites, forums, social networks, blogs and other websites. These opinions constitute a valuable resource for businesses, governments and consumers. In the last years, some researchers have proposed opinion extraction systems, mostly domain-independent ones, to automatically extract structured representations of opinions contained in those texts. In this work, we tackle this task in a domain-oriented approach, defining a set of domain-specific resources which capture valuable knowledge about how people express opinions on a given domain. These resources are automatically induced from a set of annotated documents. Some experiments were carried out on three different domains (user-generated reviews of headphones, hotels and cars), comparing our approach to other state-of-the-art, domain-independent techniques. The results confirm the importance of the domain in order to build accurate opinion extraction systems. Some experiments on the influence of the dataset size and an example of aggregation and visualization of the extracted opinions are also shown