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[EN] In this work, ZnO nanowires with high aspect ratio were obtained by fast and simple electrochemical anodization. Morphological, structural and photoelectrochemical characteristics of the synthesized ZnO nanowires were evaluated by using different techniques: field emission scanning electron microscopy, atomic force microscopy, high resolution transmission electron microscopy, Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, UV-VIS spectroscopy, Mott-Schottky analysis and photoelectrochemical impedance spectroscopy. The synthesized ZnO nanowires presented high roughness and high crystallinity. Besides, surface defects were identified in the sample. The value of the donor density (ND) was in the order of 1019 cm-3 in the dark and 1020 cm-3 under illumination. In addition, the ZnO nanowires presented good photosensibility, with a photocurrent density response 85 times higher than a ZnO compact layer, and lower resistance to charge transfer. The charge transfer processes taking place at the ZnO/electrolyte interface were studied, since these processes strongly influence the photoelectrocatalytic efficiency of the material. According to the results, the charge transfer of holes in the synthesized ZnO nanowires occurs indirectly via surface states. In this regard, surface states may be an important feature for photoelectrocatalytic applications since they could provide lower onset voltages and higher anodic current densities., Authors would like to express their gratitude to the Generalitat Valenciana and to the European Social Fund for their financial support within the subvention GJIDI/2018/A/067. Authors also thank to project co-funded by FEDER operational programme 2014-2020 of Comunitat Valenciana (IDIFEDER/18/044). Finally, authors thank to Ministerio de Ciencia e Innovacion-Agencia Estatal de Investigacion (PID2019-105844RB-I00/AEI/10.13039/501100011033) and MINECO for its help in the Laser Raman Microscope acquisition (UPOV08-3E-012) co -financed by the European Social Fund. Authors would also like to ex-press their gratitude for the financial support to the Generalitat Valenciana (GV/2021/011). Authors also thanks MINECO for MAT2017-84118-C2-1-R MCIN/AEI/10.13039/501100011033/project and FEDER Una manera de hacer Europa.

[EN] Problem-Based Learning (PBL) is a teaching methodology which uses comprehensive real-world problems to introduce the different concepts of the course to students. In this way, PBL methodology tries to develop, among others, problem-solving abilities, communication skills, critical thinking skills, and, the most important, it can promote life-long learning. PBL methodology was introduced to design the classes of a corrosion course. Corrosion is a course which belongs to the Master of Chemical Engineering and to the Master of Industrial Security and Environmental of the Universitat Politècnica de Valencia (Spain). In this study it is explained how PBL methodology was designed to cover all the concepts of the course in order that students could acquire generic, technical and specific competences. The crucial part to succeed in the implementation of the PBL methodology is the design of the problems. In the study it is detailed how problems were designed and the main difficulties found during the implementation of the methodology in the corrosion course., Authors would like to express their gratitude to the project PIME: Aprendizaje Basado en Problemas para su aplicación en las áreas de Ingeniería Química y de Materiales (Ref. 27) and to the Instituto de Ciencias de la Educación and the Vicerrectorado de Estudios, Calidad y Acreditación from the Universitat Politècnica de Valencia, for their financial and technical support.

Introducción. La reacción a la prueba cutánea de Montenegro (a leishmanina) y la lesión de leishmaniasis comparten características fundamentales de la reacción de hipersensibilidad de tipo retardado. Objetivos. Determinar si la respuesta cutánea a leishmanina se aproxima y podría modelar la respuesta inflamatoria e inmune temprana a la infección por Leishmania. Materiales y métodos. Este estudio comparó la respuesta inflamatoria de biopsias de lesiones agudas (tiempo de evolución £1 mes) y lesiones crónicas (tiempo de evolución ³6 meses) con su respectiva reacción a la prueba cutánea de Montenegro, y con la reacción a la prueba de Montenegro de individuos infectados asintomáticos. Resultados. La proporción de linfocitos T CD4+ y CD8+, células fagocíticas mononucleares y granulocitos fue similar entre lesiones agudas y sus reacciones a la prueba cutánea a leishmanina. En contraste, los linfocitos CD4+ (32,6%) representaron una proporción significativamente mas baja, y los linfocitos B (20%) y macrófagos (27%) una proporción significativamente más alta del infiltrado celular en lesiones crónicas que en sus correspondientes reacciones a la prueba cutánea de Montenegro (CD4+: 43,7%, linfocitos B: 0.9%; macrófagos: 17,5%). Se encontró una asociación positiva entre linfocitos T CD8+ y macrófagos ( P=0,038) en la reacción a la prueba cutánea de Montenegro de los individuos con infección asintomática, mientras que los linfocitos T CD8+ y CD4+ estuvieron asociados positivamente en las reacciones a la prueba cutánea de Montenegro de pacientes crónicos ( P=0,002). Adicionalmente, la proporción de linfocitos B en lesiones crónicas (20%) fue más alta que en lesiones agudas (5,3%) ( P=0,002). Conclusión. La reacción cutánea de Montenegro permitió diferenciar la respuesta celular inmune entre infección asintomática y enfermedad crónica, y simula la respuesta temprana a la infección. Introduction. The Montenegro skin test reaction and leishmaniasis lesions share fundamental characteristics of a delayed type hypersensitivity reaction. Objectives. To determine whether the Montenegro skin test reaction (response to leishmanin) might approximate and thereby provide insight into the early inflammatory and immune response to Leishmania infection. Materials and methods. We compared the inflammatory response in biopsies of acute (evolution time £one month), and chronic lesions (evolution time ³6 months) with the Montenegro skin test reaction in the corresponding patients, and with the Montenegro skin test of asymptomatically infected volunteers. Results. The proportion of CD4+ and CD8+ T lymphocytes, mononuclear phagocytes and granulocytes were similar in acute lesions and in their corresponding Montenegro skin test reactions. In contrast, CD4+ lymphocytes (32.6%) represented a significantly lower, and B cells (20%) and macrophages (27%) a significantly higher proportion of the cellular infiltrate in chronic lesions as compared to reactions in the corresponding skin test site (CD4+: 43.7%, B cells: 0.9%; macrophages: 17.5%). CD8+ T lymphocytes and macrophages were positively associated ( P=0.038) in the Montenegro skin test of asymptomatically infected individuals whereas CD8+ and CD4+ T cells were positively associated in the Montenegro skin test of chronic patients ( P=0.002). Notably, B cells were markedly more frequent in chronic lesions (20%) than in acute lesions (5.3%) ( P=0.002). Conclusion. The Montenegro skin test distinguished the cellular immune response to Leishmania in asymptomatic infection and chronic disease and may provide a surrogate of the early response to infection.

"The Pleistocene was climatically variable worldwide. In Mexico, climatic changes have been primarily studied in central and northern regions of the country, particularly in regard to marine isotope stage 2 (MIS 2). The paleoenvironments of the previous interglacial, MIS 3, remain less known, especially in the south. In the present work, the results for an alluvial pedosequence in Santa Cruz Nuevo, Puebla are presented; the large and small vertebrates recovered from this locality were used to reconstruct past paleoenvironments. However, it was found that the suite of fossil microvertebrates used here was more informative than that of the macrofossils because they are still extant, thus allowing insights into their ecology. Radiocarbon dating of the pedosequence indicates it was formed during MIS 3, around 30,000 radiocarbon years before present. Four pedological units were recognized: stagnogleyic, carbonate, gley and humus. With the exception of the carbonate unit, fossils were retrieved from all pedological units. Paleosols varied between Fluvisols and Gleysols, neither of which is diagnostic of any particular climate. Nevertheless, they are both hydromorphic, a condition that could result from intermittent flooding. At the base of the section, in the stagnogleyic unit, the presence of mammoth bones in conjunction with negative values of δ 13 C (-23.3 ‰) in paleosols suggest the existence of grassland with a dominance of C3 grasses. The isotopic values are similar in the succeeding units (-23 to -22 ‰); however, the fossil association found in Santa Cruz Nuevo indicates the incorporation of shrubland faunas. It can thus be inferred that the plant composition in Santa Cruz Nuevo comprised C3 grasses and CAM metabolic succulents such as cacti and magueys. Hydrated CAM plants use the ribulose 1,5-biphosphate (RBP) carboxilase enzyme, which produces negative values comparable to those of C3 plants. The uppermost unit, the humus, has a similar fossil association, but in spite of this, the paleosol-based isotopic values suggest a vegetation mix, indicated by the presence of C4 plants such as grasses. The comparison of our results with other records suggests that the end of MIS 3 was a dry phase which changed to humid, and in some places cool conditions, during MIS 2. No MIS 2 record is preserved in the Santa Cruz Nuevo pedosequence. The comparison of the modern soil and climate with our pedosequence shows more humid conditions during MIS 3. Finally, and although the microvertebrate associations are similar to extant ones, the macrovertebrates also encompass extinct taxa."

This work was supported by grants from the following institutions: Grant for international postdoctoral stay. Jose Castillejo Program (Grant CAS15/00257), Ministerio de Educación Cultura y Deporte. Gobierno de España. Proyecto de Investigación en Salud, Consejería de Salud y Familias (Grant PI-0139-2018). EU-ERDF-Instituto de Salud Carlos III (Grant PI19/01577). Proyectos dedesarrollo tecnológico, Ministerio de Ciencia e Innovación (Grant DTS19/00125). Ministerio de Economía, Industria y Competitividad (Grant RTC-2019-007329-1).

Deficiency of pregnancy-associated plasma protein-A2 (PAPP-A2), an IGF-1 availability regulator, causes postnatal growth failure and dysregulation of bone size and density. The present study aimed to determine the effects of recombinant murine IGF-1 (rmIGF-1) on bone composition and remodeling in constitutive Pappa2 knock-out (ko/ko) mice. To address this challenge, X-ray diffraction (XRD), attenuated total reflection-fourier transform infra-red (ATR-FTIR) spectroscopy and gene expression analysis of members of the IGF-1 system and bone resorption/formation were performed. Pappa2ko/ko mice (both sexes) had reduced body and bone length. Male Pappa2ko/ko mice had specific alterations in bone composition (mineral-to-matrix ratio, carbonate substitution and mineral crystallinity), but not in bone remodeling. In contrast, decreases in collagen maturity and increases in Igfbp3, osteopontin (resorption) and osteocalcin (formation) characterized the bone of Pappa2ko/ko females. A single rmIGF-1 administration (0.3 mg/kg) induced short-term changes in bone composition in Pappa2ko/ko mice (both sexes). rmIGF-1 treatment in Pappa2ko/ko females also increased collagen maturity, and Igfbp3, Igfbp5, Col1a1 and osteopontin expression. In summary, acute IGF-1 treatment modifies bone composition and local IGF-1 response to bone remodeling in mice with Pappa2 deficiency. These effects depend on sex and provide important insights into potential IGF-1 therapy for growth failure and bone loss and repair.