Análisis de la influencia del endurecimiento por precipitación en la respuesta de una unión soldada a ensayos ERR y EPRDL

En este trabajo se estudia la influencia del endurecimiento por precipitación en las distintas zonas que conforman al material tras una soldadura por puntos. Se comparan dos pruebas diferentes de reactivación electroquímica, el ensayo EPR y el EPRDL. Se estableció una metodología cuantitativa a través de la cuál se verifica que el mejor comportamiento se consigue con un tratamiento de sensibilización a 720°C para tiempos de exposición bajos, correspondiente a las 0,5 horas para ambos ensayos.Departamento de Ciencias de los Materiales e Ingeniería Metalúrgica, Expresión Gráfica en la Ingeniería, Ingeniería Cartográfica, Geodesia y Fotogrametría, Ingeniería Mecánica e Ingeniería de los Procesos de FabricaciónGrado en Ingeniería Mecánic

Gender differences in dual diagnoses associated with cannabis use: A review

Gender differences in psychiatric disorders and drug use are well known. Cannabis is the most widely used illegal drug among young people. In recent years, its use has been related to the development of psychiatric pathologies; however, few studies have incorporated the gender perspective as of yet. The present work analyses the literature to determine the existence of gender differences in the development of psychotic, depressive and anxious symptoms associated with cannabis use. First, we describe cannabis misuse and its consequences, paying special attention to adolescent subjects. Second, the main gender differences in psychiatric disorders, such as psychosis, depression, anxiety and cannabis use disorders, are enumerated. Subsequently, we discuss the studies that have evaluated gender differences in the association between cannabis use and the appearance of psychotic, depressive and anxious symptoms; moreover, we consider the possible explanations for the identified gender differences. In conclusion, the studies referred to in this review reveal the existence of gender differences in psychiatric symptoms associated with cannabis use, although the direction of such differences is not always clear. Future research is necessary to discern the causal relationship between cannabis use and the development of psychiatric symptoms, as well as the gender differences foun

Escritos de Virginia Bolten

Escritos de Virginia Bolten reunidos, editados y publicados en el contexto del presente Dossier

Tras los pasos de Virginia Bolten

Este trabajo es una biografía política e intelectual de Virginia Bolten, una de las anarquistas más reconocidas en la historia del movimiento obrero de Argentina y Uruguay. Tanto en la memoria militante como en el relato historiográfico, la vida de Bolten surge como un conjunto de imágenes poderosas e insistentes. La audaz que arengó a las masas en 1890. La feminista redomada que concibió el periódico La Voz de la Mujer. La joven llamativa que descubrió Bialet Massé en su informe de 1904. La militante mujer detenida y deportada. Sobre esas imágenes sueltas trabajaron los autores de este artículo, con el objetivo de revisarlas y establecer puntos de referencia para dar cuenta de los tramos más significativos de la actuación de Bolten en la primera parte de su vida.  Para esta edición de Políticas de la Memoria han recuperado veinte intervenciones de Bolten en la prensa durante las primeras décadas de su militancia. Se incluyen, también, algunas fotos provenientes del archivo familiar y el acta de bautismo de 1880

Endocannabinoid and nitric oxide-dependent IGF-I-mediated synaptic plasticity at mice barrel cortex

Insulin-like growth factor-I (IGF-I) signaling plays a key role in learning and memory. IGF-I increases the spiking and induces synaptic plasticity in the mice barrel cortex (Noriega-Prieto et al., 2021), favoring the induction of the long-term potentiation (LTP) by Spike Timing-Dependent Proto-cols (STDP) (Noriega-Prieto et al., 2021). Here, we studied whether these IGF-I effects depend on endocannabinoids (eCBs) and nitric oxide (NO). We recorded both excitatory postsynaptic currents (EPSCs) and inhibitory postsynaptic currents (IPSCs) evoked by stimulation of the basal dendrites of layer II/III pyramidal neurons of the Barrel Cortex and analyzed the effect of IGF-I in the presence of a CB1 R antagonist, AM251, and inhibitor of the NO synthesis, L-NAME, to prevent the eCBs and the NO-mediated signaling. Interestingly, L-NAME abolished any modulatory effect of the IGF-I-induced excitatory and inhibitory transmission changes, suggesting the essential role of NO. Surprisingly, the inhibition of CB1Rs did not only block the potentiation of EPSCs but reversed to a depression, highlighting the remarkable functions of the eCB system. In conclusion, eCBs and NO play a vital role in deciding the sign of the effects induced by IGF-I in the neocortex, suggesting a neuromodulatory interplay among IGF-I, NO, and eCBsThis research was funded by MINECO and MICINN grants number BFU2016-80802-P AEI/FEDER, UE (MINECO) and PID2020-119358GB-I00/AEI/10.13039/501100011033 (MICINN).The APC was funded by PID2020-119358GB-I00/AEI/10.13039/501100011033 (MICINN

Problems and tax sharing reform and grants in autonomous communities

RESUMEN. En este trabajo se analiza la evolución de las cestas de impuestos y de los sistemas de transferencias en el marco de la financiación de las Comunidades Autónomas de régimen común así como su configuración con el modelo actual, una vez conocido el cierre de la última liquidación de 2006. Se hace especial hincapié en la posibilidad de actualizar las transferencias por parte del Estado (hasta ahora quinquenal) o establecer un período de ajuste gradual, ya que sino se corre el riesgo de que la evolución de la financiación según necesidades de gasto con comportamiento expansivo provoque no sólo la desnivelación entre regiones sino lo ocurrido en los anteriores quinquenios, es decir, problemas de suficiencia financiera. Finalmente, no hay que olvidar el hecho de que sí la nivelación resulta muy evidente podría cuestionarse el patrón de equidad interterritorial a semejanza de lo ocurrido en la experiencia comparada.ABSTRACT. In this paper the evolution of tax sharing and grants in the framework of the common Autonomous Communities´ financing model with last data of 2006 is analyzed. We point out the possibility of upgrading grants from the central government (up to now five-year periods) or to settle down a gradual adjustment, due to the risk that the evolution of financing according to expenditure needs with expansible behaviour causes no equalisation among regions but that happened in the previous five year period, like problems of financial sufficiency. Finally, if equalisation is very evident the pattern of equity among Autonomous Communities could be questioned as happen in the compared experience

Ceramide metabolism regulates autophagy and apoptotic-cell death induced by melatonin in liver cancer cells

P. 178-189Autophagy is a process that maintains homeostasis during stress, although it also contributes to cell death under specific contexts. Ceramides have emerged as important effectors in the regulation of autophagy, mediating the crosstalk with apoptosis. Melatonin induces apoptosis of cancer cells; however, its role in autophagy and ceramide metabolism has yet to be clearly elucidated. This study was aimed to evaluate the effect of melatonin administration on autophagy and ceramide metabolism and its possible link with melatonininduced apoptotic cell death in hepatocarcinoma (HCC) cells. Melatonin (2 mM) transiently induced autophagy in HepG2 cells through JNK phosphorylation, characterized by increased Beclin1 expression, p62 degradation and LC3II and LAMP2 colocalization, which translated in decreased cell viability. Moreover, ATG5-silencing sensitized HepG2 cells to melatonin induced-apoptosis, suggesting a dual role of autophagy in cell death. Melatonin enhanced ceramide levels through both de novo synthesis and acid sphingomyelinase (ASMase) stimulation. Serine palmitoyl transferase (SPT) inhibition with myriocin prevented melatonin induced autophagy and ASMase inhibition with imipramine impaired autophagy flux. However, ASMase inhibition partially protected HepG2 cells against melatonin while SPT inhibition significantly enhanced cell death. Findings suggest a cross-talk between SPTmediated ceramide generation and autophagy in protecting against melatonin, while specific ASMase-induced ceramide production participates in melatonin-mediated cell death. Thus, dual blocking of SPT and autophagy emerge as a potential strategy to potentiate the apoptotic effects of melatonin in liver cancer cell

Magnetosomes could be protective shields against metal stress in magnetotactic bacteria

Magnetotactic bacteria are aquatic microorganisms with the ability to biomineralise membrane-enclosed magnetic nanoparticles, called magnetosomes. These magnetosomes are arranged into a chain that behaves as a magnetic compass, allowing the bacteria to align in and navigate along the Earth's magnetic field lines. According to the magneto-aerotactic hypothesis, the purpose of producing magnetosomes is to provide the bacteria with a more efficient movement within the stratified water column, in search of the optimal positions that satisfy their nutritional requirements. However, magnetosomes could have other physiological roles, as proposed in this work. Here we analyse the role of magnetosomes in the tolerance of Magnetospirillum gryphiswaldense MSR-1 to transition metals (Co, Mn, Ni, Zn, Cu). By exposing bacterial populations with and without magnetosomes to increasing concentrations of metals in the growth medium, we observe that the tolerance is significantly higher when bacteria have magnetosomes. The resistance mechanisms triggered in magnetosome-bearing bacteria under metal stress have been investigated by means of x-ray absorption near edge spectroscopy (XANES). XANES experiments were performed both on magnetosomes isolated from the bacteria and on the whole bacteria, aimed to assess whether bacteria use magnetosomes as metal storages, or whether they incorporate the excess metal in other cell compartments. Our findings reveal that the tolerance mechanisms are metal-specific: Mn, Zn and Cu are incorporated in both the magnetosomes and other cell compartments; Co is only incorporated in the magnetosomes, and Ni is incorporated in other cell compartments. In the case of Co, Zn and Mn, the metal is integrated in the magnetosome magnetite mineral core.Te Spanish and Basque Governments are acknowledged for funding under projects number MAT2017- 83631-C3-R and IT-1245-19, respectively. Dr. L. Marcano acknowledges the fnancial support provided through a postdoctoral fellowship from the Basque Government

Memory inhibition as a critical factor preventing creative problem solving.

[EN]The hypothesis that reduced accessibility to relevant information can negatively affect problem solving in a remote associate test (RAT) was tested by using, immediately before the RAT, a retrieval practice procedure to hinder access to target solutions. The results of 2 experiments clearly showed that, relative to baseline, target words that had been competitors during selective retrieval were much less likely to be provided as solutions in the RAT, demonstrating that performance in the problem-solving task was strongly influenced by the predetermined accessibility status of the solutions in memory. Importantly, this was so even when participants were unaware of the relationship between the memory and the problem-solving procedures in the experiments. This finding is consistent with an inhibitory account of retrieval-induced forgetting effects and, more generally, constitutes support for the idea that the activa tion status of mental representations originating in a given task (e.g., episodic memory) can unwittingly have significant consequences for a different, unrelated task (e.g., problem solving

Enzymatic fine-tuning for 2-(6-hydroxynaphthyl) β-d-xylopyranoside synthesis catalyzed by the recombinant β-xylosidase BxTW1 from Talaromyces amestolkiae

This article is distributed under the terms of the Creative Commons Attribution 4.0 International License.-- et al.[Background]: Glycosides are compounds displaying crucial biological roles and plenty of applications. Traditionally, these molecules have been chemically obtained, but its efficient production is limited by the lack of regio- and stereo-selectivity of the chemical synthesis. As an interesting alternative, glycosidases are able to catalyze the formation of glycosides in a process considered green and highly selective. In this study, we report the expression and characterization of a fungal ß-xylosidase in Pichia pastoris. The transglycosylation potential of the enzyme was evaluated and its applicability in the synthesis of a selective anti-proliferative compound demonstrated. [Results]: The ß-xylosidase BxTW1 from the ascomycete fungus Talaromyces amestolkiae was cloned and expressed in Pichia pastoris GS115. The yeast secreted 8 U/mL of ß-xylosidase that was purified by a single step of cation-exchange chromatography. rBxTW1 in its active form is an N-glycosylated dimer of about 200 kDa. The enzyme was biochemically characterized displaying a K m and k cat against p-nitrophenyl-ß-d-xylopyranoside of 0.20 mM and 69.3 s¿1 respectively, and its maximal activity was achieved at pH 3 and 60 °C. The glycan component of rBxTW1 was also analyzed in order to interpret the observed loss of stability and maximum velocity when compared with the native enzyme. A rapid screening of aglycone specificity was performed, revealing a remarkable high number of potential transxylosylation acceptors for rBxTW1. Based on this analysis, the enzyme was successfully tested in the synthesis of 2-(6-hydroxynaphthyl) ß-d-xylopyranoside, a well-known selective anti-proliferative compound, enzymatically obtained for the first time. The application of response surface methodology, following a Box-Behnken design, enhanced this production by eightfold, fitting the reaction conditions into a multiparametric model. The naphthyl derivative was purified and its identity confirmed by NMR. [Conclusions]: A ß-xylosidase from T. amestolkiae was produced in P. pastoris and purified. The final yields were much higher than those attained for the native protein, although some loss of stability and maximum velocity was observed. rBxTW1 displayed remarkable acceptor versatility in transxylosylation, catalyzing the synthesis of a selective antiproliferative compound, 2-(6-hydroxynaphthyl) ß-d-xylopyranoside. These results evidence the interest of rBxTW1 for transxylosylation of relevant products with biotechnological interest.This work was carried out with funding from projects BIO2015-68387-R, RTC-2014-1777-3 and CTQ2015-64597-C2 from MINECO and S2013/MAE2972 from Comunidad de Madrid, as well as from the Natural Sciences and Engineering Research Council of Canada. M. Nieto-Domínguez thanks the MINECO for an FPU fellowship.We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI).Peer Reviewe