Sobre un resultado de no existencia de soluciones positivas para un problema elíptico en el semi–espacio

Resultados del tipo Liouville en R N o en el semi–espacio R N + pueden ser importantes para la obtención de estimaciones a priori en problemas asociados en dominios acotados, via algún procedimiento de blow-up. En esta presentación mostramos un resultado de no existencia de soluciones positivas de u p ≤ −∆ mu ≤ Cup , en el semi–espacio

Comparación de dos métodos de análisis de imágenes digitales para la determinación del color: modelo RGB y el análisis de espectro de luz

68 p.El color de una fruta puede entregar información precisa sobre ´esta, por ejemplo, su estado de madurez. Realizar una medición de esta característica de forma no invasiva se vuelve una necesidad, para no alterar su estado natural, es por esto que el análisis del color a través de imagines digitales es una herramineta idónea. En esta memoria se realiza un análisis del espectro de luz reflejado por la frutilla chilena, logrando obtener una caracterización de espectros de luz mediante la función de densidad de la distribución normal y utilizando la eficiencia cuántica de un sensor CMOS, se obtiene un valor RGB para cada uno de ellos, llegando finalmente a una tabla de asociación que permite que se utilice una cámara fotográfica digital para obtener espectros de luz aproximados con una presición cercana a la que ofrece un espectrofotometro comercial. También se presenta una aplicación donde se determina la longitud de onda dominante de los aquenios en la frutilla chilena./ABSTRACT: The color of a fruit can give accurate information about it, eg, state of maturity. Perform a measurement of this characteristic of noninvasive becomes a necessity, not to alter their natural state, which is why the analysis of color digital images through a tool is ideal. In this report an analysis of the spectrum of light reflected by the Chilean strawberry, obtaining a characterization of spectra of light by density function of normal distribution and using the quantum efficiency of a CMOS sensor, an RGB value is obtained for each, finally reaching an association table that allows you to use a digital camera for light spectra with a precision close approximate to that offered by a commercial spectrophotometer. It also presents an application that determines the dominant wavelength of the Chilean strawberry achenes

Tracking kelp-type seaweed fuel in the archaeological record through Raman spectroscopy of charred particles: examples from the Atacama Desert coast

The use of seaweed as fuel has been mentioned in ethnographic and historical sources of different coastal regions. Nevertheless, the archaeological record of seaweed burning is still limited to contexts where preservation is exceptional and macroscopic discrimination of charred remains is possible. Here, we evaluate the effectiveness of Raman spectroscopy in discriminating seaweed vs. plant/wood char. Our dataset (N = 92) consists of modern and archaeological seaweed and plant/wood charred remains, including specimens of unknown origin from the Atacama Desert coast, Northern Chile. The charred samples were processed to obtain 13 parameters which were then fed into five supervised machine learning models. The models, built on samples of known origin (seaweed and plant/wood), performed remarkably well in terms of accuracy, kappa, sensitivity, and specificity. The models were used for final predictions on 10 non-identified archaeological charcoals. Our results suggest that Raman spectroscopy combined with machine learning techniques is a robust methodology for discriminating seaweed and plant/wood charred remains in the archaeological record. The predictions on unknown samples confirm that seaweed was used as fuel in a specific funerary ritual in the southern Atacama Desert coast around 5000 cal BP. Furthermore, charred specimens of Lessonia spp. recovered from combustion features in other northern Chile coastal settlements, suggest that seaweed pyrotechnology developed by Atacama Desert coast people is likely a long-term process. As for coastal archaeology, this work encourages new research on seaweed as an alternative/main fuel in coastal deserts and evaluates possible bias for chronologies from coastal archaeological settlements around the globe.The present study was supported by the Universidad de Tarapacá (Chile) through the research grants UTA MAYOR 3754 (2021–2022) – “Uso de algas como combustible en sitios arqueológicos de la costa desértica de Atacama: una aproximación arqueomética” and UTA MAYOR 367122 (2022–2024) – “Estudio multiproxy para el reconocimiento de algas en rasgos de combustión arqueológicos de la costa del Desierto de Atacama” (Universidad de Tarapacá, Chile). D.Z. received financial support from the Arqueología, desiertos costeros y visibilización de recursos naturales Project (PIE 190405, CSIC) and ARVCODA – Arqueología de los Recursos Vegetales en la Costa del Desierto de Atacama project (Fundación PALARQ, CSIC). The studied samples were obtained during archaeological excavations or samplings performed in the following projects: FONDECYT 1151203; FONDECYT POSTDOC 3150664; and Quebrada Blanca Phase 2 (QB2) project – Compañía Minera Teck Quebrada Blanca S.A

Cis- and trans-regulatory mechanisms of gene expression in the ASJ sensory neuron of Caenorhabditis elegans

© 2015 by the Genetics Society of America. The identity of a given cell type is determined by the expression of a set of genes sharing common cis-regulatory motifs and being regulated by shared transcription factors. Here, we identify cis and trans regulatory elements that drive gene expression in the bilateral sensory neuron ASJ, located in the head of the nematode Caenorhabditis elegans. For this purpose, we have dissected the promoters of the only two genes so far reported to be exclusively expressed in ASJ, trx-1 and ssu-1. We hereby identify the ASJ motif, a functional cis-regulatory bipartite promoter region composed of two individual 6 bp elements separated by a 3 bp linker. The first element is a 6 bp CG-rich sequence that presumably binds the Sp family member zinc-finger transcription factor SPTF-1. Interestingly, within the C. elegans nervous system SPTF-1 is also found to be expressed only in ASJ neurons where it regulates expression of other genes in these neurons and ASJ cell fate. The second element of the bipartite motif is a 6 bp AT-rich sequence that is predicted to potentially bind a transcription factor of the homeobox family. Together, our findings identify a specific promoter signature and SPTF-1 as a transcription factor that functions as a terminal selector gene to regulate gene expression in C. elegans ASJ sensory neurons.Some C. elegans strains were provided by the CGC, which is funded by the National Institutes of Health Office of Research Infrastructure Programs (P40 OD010440), and by the Japanese National Bioresource Project, which is funded by the Japanese Ministry of Education, Culture, Sport, Science and Technology. We thank Nuria Flames for advice and support and María Jesús Rodríguez-Palero and Francisco José Naranjo-Galindo for excellent technical assistance. This work was financed by grants to A.M.-V. from the Junta de Andalucía (Projects P07-CVI-02697 and P08-CVI-03629). Work in the laboratory of P.S. was supported by grants from the Swedish Research Council and the Torsten Söderberg Foundation. E.K. was supported by a grant from the European Union FP6 Marie Curie Research Training Network “EUrythron” MRTN-CT-2004-005499.Peer Reviewe

Role of wild ruminants in the epidemiology of bluetongue virus serotypes 1, 4 and 8 in Spain

Although the importance of wild ruminants as potential reservoirs of bluetongue virus (BTV) has been suggested, the role played by these species in the epidemiology of BT in Europe is still unclear. We carried out a serologic and virologic survey to assess the role of wild ruminants in the transmission and maintenance of BTV in Andalusia (southern Spain) between 2006 and 2010

2D copper-imidazolate framework without thermal treatment as an efficient ORR electrocatalyst for Zn–air batteries

To face unmet energy demands, the search for more stable, low-cost, and scalable electrocatalyst materials is imperative. Within this context, single-atom catalysts (SACs) have drawn considerable attention due to their maximum atom utilization. With this idea in mind, we have synthesized a new ultrathin and water-stable 2D Cu-based metal-organic framework (2DCIFs), which presents a notable electrocatalytic activity for oxygen reduction reaction (ORR) in alkaline media without the need of calcination, which makes the difference when compared to most MOF-based electrocatalysts. The designed MOF-based SAC consists of single-atom sites (isolated and accessible Cu) coordinated to imidazole carboxylic ligands, giving rise to Cu-N4O actives sites confined into a 2D-nanostructured network. This unique structure, along with the ultrathin nature of nanosheets that favors mass transport and electrical conductivity, and the high chemical stability of these 2DCIFs are the key features of the excellent ORR performance, which occurs by a direct four-electron transfer pathway, an onset potential of 0.86 V vs RHE and a maximum current density of 6.4 mA·cm-2. These good catalytic properties of 2DCIFs have allowed their use as efficient air electrodes in alkaline flooded and all-solid-state Zn-air batteries. In the former case, 2DCIFsbased air electrodes presented a specific power density of 91.2 kW·cm-2·kg-1 and a specific capacity of 296.2 A·h·g-1, significantly exceeding the specific capacity values reported previously for other Cu-based catalysts. Besides, the specific capacity increased to 389.1 A·h·g-1 when 2DCIFs were tested in an all-solid-state Zn-air battery

Catalytic activity of MWCNT-based inks synthetized by different methods

Abstract of the poster presented at "Current Trends in Electrochemistry", 41st Meeting of the Electrochemistry Group of the Spanish Royal Society of Chemistry and 1st French-Spanish Atelier/Workshop on Electrochemistry, Paris (July 6 - 9, 2021).Research on new catalyst materials for the oxygen reduction reaction (ORR) is the main goal for many research groups around the world, due to its application in fuel cells and metal/air batteries. ORR mainly occurs by two pathways, in alkaline media, the direct four-electron transfer pathway from O2 to OH- or in a two-steps mechanism, where hydrogen peroxide (HO2-) is formed in the first reaction. On fuel cells and metal air batteries applications, the catalyst must be optimized to get the oxygen reduced directly to water through the 4 electrons mechanism1. Due to high price of the precious metals, new materials are tested to be used as catalyst in ORR. Among them, researchers have focused their attention mainly on metal oxides, perovskites or carbonaceous materials. In this communication, we have studied four carbonaceous-based inks synthetized by ultrasonic or hydrothermal methods2, using a rotating ring-disk electrode (RRDE) (Figure 1.A). The production of HO2- (%HO2-), transferred electrons and others parameters will be analyzed and the results will be discussed in depth. Finally, the inks were used as catalysts in the cathode of a PVA-KOH-based zinc/air batteries to replace the most widely used catalyst to date, MnO2The authors thank the financial support from Fundación Séneca (Región de Murcia, Spain; Ref: 20985/PI/18 and 19882-GERM-15), Spanish Agencia Estatal de Investigación (PID2019-104272RB-C55/ AEI/10.13039/501100011033 and PID2019-104272RB-C51/AEI/10.13039/501100011033), and Gobierno de Aragón (DGA T03_20R).Peer reviewe

Generation of periventricular reactive astrocytes overexpressing aquaporin 4 Is stimulated by mesenchymal stem cell therapy

Aquaporin-4 (AQP4) plays a crucial role in brain water circulation and is considered a therapeutic target in hydrocephalus. Congenital hydrocephalus is associated with a reaction of astrocytes in the periventricular white matter both in experimental models and human cases. A previous report showed that bone marrow-derived mesenchymal stem cells (BM-MSCs) transplanted into the lateral ventricles of hyh mice exhibiting severe congenital hydrocephalus are attracted by the periventricular astrocyte reaction, and the cerebral tissue displays recovery. The present investigation aimed to test the effect of BM-MSC treatment on astrocyte reaction formation. BM-MSCs were injected into the lateral ventricles of four-day-old hyh mice, and the periventricular reaction was detected two weeks later. A protein expression analysis of the cerebral tissue differentiated the BM-MSC-treated mice from the controls and revealed effects on neural development. In in vivo and in vitro experiments, BM-MSCs stimulated the generation of periventricular reactive astrocytes overexpressing AQP4 and its regulatory protein kinase D-interacting substrate of 220 kDa (Kidins220). In the cerebral tissue, mRNA overexpression of nerve growth factor (NGF), vascular endothelial growth factor (VEGF), hypoxia-inducible factor-1 (HIF1α), and transforming growth factor beta 1 (TGFβ1) could be related to the regulation of the astrocyte reaction and AQP4 expression. In conclusion, BM-MSC treatment in hydrocephalus can stimulate a key developmental process such as the periventricular astrocyte reaction, where AQP4 overexpression could be implicated in tissue recovery.The present work was supported by grants PI15/00619 and PI19/00778 (to A.J.J. and P.P.-G.), PI21/000914 (to J.V.) and PI21/000915 (to A.G.) from the Instituto de Salud Carlos III, Spain, co-financed by FEDER funds from the European Union; PI18-RT-2233 from Junta de Andalucía (to A.G.) co-financed by Programa Operativo FEDER 2014–2020; PID2020-115218RB-I00 to T.I., funded by MCIN/AEI/10.13039/501100011033; Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED, Instituto de Salud Carlos III, Spain) to J.V., T.I. and A.G.; FPU13/02906 to MG-B from the Ministerio de Educación, Cultura y Deporte, Spain; RYC-2014-16980 to P.P.-G. from the Ministerio de Economía y Competitividad, Spain; UMA18-FEDERJA-277 from Plan Operativo FEDER Andalucía 2014–2020 and Universidad de Málaga to P.P.-G.; Proyectos dirigidos por jóvenes investigadores from Universidad de Málaga to P.P.-G. The cost of this publication has been paid in art by “ERDF A way of making Europe” funds. Partial funding for open access charge: Universidad de Málaga