Solid Polymer Electrolytes Based on Polylactic Acid Nanofiber Mats Coated with Polypyrrole

This is the peer reviewed version of the following article: Gisbert, F., García-Bernabé, A., Compañ, V., Martínez-Ramos, C., Monleón, M., Solid Polymer Electrolytes Based on Polylactic Acid Nanofiber Mats Coated with Polypyrrole. Macromol. Mater. Eng. 2021, 306, 2000584, which has been published in final form at https://doi.org/10.1002/mame.202000584. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.[EN] The production of electroconductive nanofiber membranes made from polylactic acid (PLA) coated with polypyrrole (PPy) is investigated, performing a scanning of different reaction parameters and studying their physicochemical and dielectric properties. Depending on PPy content, a transition between conduction mechanisms is observed, with a temperature-dependent relaxation process for samples without PPy, a temperature-independent conduction process for samples with high contents of PPy and a combination of both processes for samples with low contents of PPy. A homogeneous and continuous coating is achieved from 23 wt% PPy, observing a percolation effect around 27 wt% PPy. Higher wt% PPy allow to obtain higher conductivities, but PPy aggregates appear from 34% wt% PPy. The high conductivity values obtained for electrospun membranes both through-plane and in-plane (above 0.05 and 0.20 S cm¿1, respectively, at room temperature) for the highest wt% of PPy, their porous structure with high specific surface area and their thermal stability below 140 °C make them candidates for many potential applications as solid polymer electrolytes in, for example, batteries, supercapacitors, sensors, photosensors, or polymer electrolyte membrane fuel cells (PEMFCs). In addition, the biocompatibility of PLA-PPy membranes expand their potential applications also in the field of tissue engineering and implantable devices.The authors acknowledge financing from the Spanish Government's State Research Agency (AEI) through projects DPI2015-72863-EXP and RTI2018-095872-B-C22/ERDF. FGR acknowledges the scholarship FPU16/01833 of the Spanish Ministry of Universities. 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Simulation study of resistor networks applied to an array of 256 SiPMs

[EN] In this work we describe a procedure to reduce the number of signals detected by an array of 256 Silicon Photo-multipliers (SiPMs) using a resistor network to divide the signal charge into few readout channels. Several configurations were modeled, and the pulsed signal at the readout contacts were simulated. These simulation results were experimentally tested on a specifically designed and manufactured set of printed circuit boards. Three network configurations were modeled. The modeling provided encouraging results for all three configurations. The measurements on the prototypes constructed for this study, however, provided useful position-sensitivity for only one of the network configurations. The lack of input signal amplification into the networks, the SiPM dark current, as well as the complexity of an eight layers board with parasitic capacitances, could have caused the degradation of resolving the impact photon position. This is hard to overcome with external printed circuit boards and components.This work was supported by the Spanish Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica (I+D+I) under Grant FIS2010-21216-CO2-01, the Valencian Local Government under Grant PROMETEO 2008/114 and through the JAE-Predoc grant from CSIC (BOE 29/01/2010).Gonzalez, A. J., Moreno, M., Barbera, J., Conde, P., Hernandez, L., Moliner, L., . . . Benlloch, J. M. (2013). Simulation study of resistor networks applied to an array of 256 SiPMs. IEEE Transactions on Nuclear Science, 60(2), 592-598. doi:10.1109/TNS.2012.2226051S59259860

Gate current analysis of AlGaN/GaN on silicon heterojunction transistors at the nanoscale

The gate leakage current of AlGaN/GaN (on silicon)high electron mobility transistor(HEMT) is investigated at the micro and nanoscale. The gate current dependence (25-310 °C) on the temperature is used to identify the potential conduction mechanisms, as trap assisted tunneling or field emission. The conductive atomic force microscopy investigation of the HEMT surface has revealed some correlation between the topography and the leakage current, which is analyzed in detail. The effect of introducing a thin dielectric in the gate is also discussed in the micro and the nanoscale

Preclinical studies with glioblastoma brain organoid co-cultures show efficient 5-ALA photodynamic therapy

Abstract: Background: The high recurrence of glioblastoma (GB) that occurs adjacent to the resection cavity within two years of diagnosis urges an improvement of therapies oriented to GB local control. Photodynamic therapy (PDT) has been proposed to cleanse infiltrating tumor cells from parenchyma to ameliorate short long-term progression-free survival. We examined 5-aminolevulinic acid (5-ALA)- mediated PDT effects as therapeutical treatment and determined optimal conditions for PDT efficacy without causing phototoxic injury to the normal brain tissue. Methods: We used a platform of Glioma Initiation Cells (GICs) infiltrating cerebral organoids with two different glioblastoma cells, GIC7 and PG88. We measured GICs-5-ALA uptake and PDT/5-ALA activity in dose-response curves and the efficacy of the treatment by measuring proliferative activity and apoptosis. Results: 5-ALA (50 and 100  g/mL) was applied, and the release of protoporphyrin IX (PpIX) fluorescence measures demonstrated that the emission of PpIX increases progressively until its stabilization at 24 h. Moreover, decreased proliferation and increased apoptosis corroborated the effect of 5-ALA/PDT on cancer cells without altering normal cells. Conclusions: We provide evidence about the effectiveness of PDT to treat high proliferative GB cells in a complex in vitro system, which combines normal and cancer cells and is a useful tool to standardize new strategic therapies

APPLICATIONS PLATFORM FOR ELECTRONIC DOCUMENTS THROUGH MOBILE COMPUTING

In this paper, an application platform for delivering academic documents in electronic format through  mobile computing is presented. The platform is service-oriented students, where they can make the  request for an academic document such as: proof of enrollment, credits studied, average, among  others. A request can be issued from a mobile device via the GSM network using the short text  messages service (SMS). Also from an Android/iOS based application designed to connect through a  wireless network which shall request the document through a Web Service. The cost of transaction  will be charged from credit line applicant or via the PayPal system. Ending with the creation of the  PDF document (electronically signed) and sent to the email of student. SEDE will provide benefts to  both: users and service providers, as they can save on costs, improve response times for applications  and mainly the ecological impact by using less paper. KEYWORDS: Electronic document, Mobile Computing, Web Services, GSM, SMS, Android, iOS.En este artículo se presenta el diseño de una plataforma de aplicaciones para la emisión de documentos académicos de manera electrónica a través de computación móvil. La plataforma está orientada al servicio de los alumnos, donde puedan realizar la solicitud de algún documento académico tales como: constancias de inscripción, créditos cursados, promedio general, entre otros. Una solicitud puede emitirse desde un dispositivo móvil a través de la red GSM, mediante mensajes de texto cortos (SMS). También desde una aplicación basada en Android/iOS diseñada para conectarse a través de una red inalámbrica la cual solicitará el documento a través de un Web Service. El cobro de la transacción se descontará del crédito de la línea telefónica del solicitante o por el sistema de cobros PayPal©, fnalizando con la creación del documento en formato PDF (frmado electrónicamente) para su envío al correo electrónico del solicitante. SEDE aportará benefcios tanto a los usuarios como a los proveedores del servicio, ya que podrán ahorrar en costos, mejorar los tiempos de respuesta de las solicitudes y principalmente el impacto ecológico al utilizar menos papel.PALABRAS CLAVES: Documento electrónico, Cómputo Móvil, Servicios Web, GSM, SMS, Android, iOS.

Primer consenso en leucemia linfocítica crónica de la agrupación mexicana para el estudio de la hematología: epidemiología, diagnóstico y tratamiento

La leucemia linfocítica crónica (LLC) es la leucemia crónica menos frecuente en México. En consideración a los avances recientes, a una mejor clasificación pronóstica y a la introducción de nuevas modalidades terapéuticas, la Agrupación Mexicana para el Estudio de la Hematología organizó el primer consenso mexicano en leucemia linfocítica crónica. Este consenso se llevó a cabo en Cancún, Quintana Roo, México, en Septiembre del 2007. Los objetivos de esta reunión fueron actualizar y compartir los conocimientos de la enfermedad entre los especialistas mexicanos, con el fin de mejorar el diagnóstico y el pronóstico de la LLC en México. En el artículo se discute los aspectos clínicos, diagnósticos y terapéuticos de la LLC

The Exceptional Fossil Site of Las Hoyas (SPAIN) from an Educational Perspective

The paleontological heritage of the fossil site of Las Hoyas (Early Cretaceous of Cuenca, Spain) is becoming a relevant part of the sociocultural identity of Castilla-La Mancha autonomous community in general, and of Cuenca province in particular. The most recent scientific advances, including several fossil findings that have had high scientific impact, have made Las Hoyas to regularly be the center of attention in the local, national, and international media, especially since the reinterpretation of the paleoecosystem represented by the locality published in 2010. These results have led to a renaissance of the interest of the society for this unique site. As a consequence, Las Hoyas has been declared Site of Cultural Interest by the regional government, in the form of paleontological zone. This recognition, which grants the locality with the highest level of protection, sets a legal framework for the educative initiatives developed at this locality, which can be categorized as non-formal education, formal education, and Social Paleontology.Unidad de Paleontología, Departamento de Biología, Universidad Autónoma de Madrid, EspañaJURASSICA Museum, SuizaDepartment of Geosciences, University of Fribourg, SuizaMuseo Geominero, Instituto Geológico y Minero de España, EspañaDepartamento de Estratigrafía, Universidad Complutense de Madrid, EspañaGéosciences Rennes Unité Mixte de Recherche, Centre National de la Recherche Scientifique, FranciaDepartamento de Ecología, Universidad Autónoma de Madrid, EspañaLaboratoire de Géologie de Lyon: Terre, Planètes, Environnement, Unité Mixte de Recherche, Centre National de la Recherche Scientifique, Franci

Transcriptome characterization by RNA sequencing identifies a major molecular and clinical subdivision in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) has heterogeneous clinical and biological behavior. Whole-genome and -exome sequencing has contributed to the characterization of the mutational spectrum of the disease, but the underlying transcriptional profile is still poorly understood. We have performed deep RNA sequencing in different subpopulations of normal B-lymphocytes and CLL cells from a cohort of 98 patients, and characterized the CLL transcriptional landscape with unprecedented resolution. We detected thousands of transcriptional elements differentially expressed between the CLL and normal B cells, including protein-coding genes, noncoding RNAs, and pseudogenes. Transposable elements are globally derepressed in CLL cells. In addition, two thousand genes-most of which are not differentially expressed-exhibit CLL-specific splicing patterns. Genes involved in metabolic pathways showed higher expression in CLL, while genes related to spliceosome, proteasome, and ribosome were among the most down-regulated in CLL. Clustering of the CLL samples according to RNA-seq derived gene expression levels unveiled two robust molecular subgroups, C1 and C2. C1/C2 subgroups and the mutational status of the immunoglobulin heavy variable (IGHV) region were the only independent variables in predicting time to treatment in a multivariate analysis with main clinico-biological features. This subdivision was validated in an independent cohort of patients monitored through DNA microarrays. Further analysis shows that B-cell receptor (BCR) activation in the microenvironment of the lymph node may be at the origin of the C1/C2 differences