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    Influence of the manufacturing strategy on the microstructure and mechanical properties of Invar 36 alloy parts manufactured by CMT-WAAM

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    The influence of the manufacturing strategy of Invar 36 alloy parts manufactured by Directed Energy Deposition by Arc (DED-Arc) also known as wire and arc additive manufacturing (WAAM) using cold metal transfer (CMT) technology has been investigated. This study focuses on the influence of applying different deposition strategies on the resulting microstructure and mechanical properties. As manufacturing costs and time are critical issues which determine the business case in WAAM applications, it is important to use the smallest possible amount of feedstock material. Therefore, different manufacturing strategies are used to obtain the variable wall thicknesses required for each part preform using WAAM as a manufacturing route. Differences in manufacturing temperature and thermal history due to different deposition strategies have been recorded. Deep microstructural analysis in as-built condition revealed that granular alignment and the crystallographic texture obtained differ between deposition strategies studied. This is the reason why there are differences in the mechanical properties, such as yield strength, ultimate tensile strength, elongation, and hardness, of the different strategies analyzed. The results revealed that the higher strength is obtained in three overlapped weld beads for the walls (514 and 581 MPa in building direction and perpendicular direction, respectively), compared to single weld bead wall (481 and 489 MPa), circular single weld bead wall (460 and 484 MPa), and meandering weld bead wall (467 and 439 MPa). The opposite is true for elongation, which is a typical correlation between strength and ductility in Fe-based alloys, having the highest elongation in the meandering weld bead wall (26 and 30%) and circular single weld bead (30 and 27%) compared to single weld bead wall (27 and 23%) and three overlapped weld bead wall (23 and 20%). It can therefore be concluded that an Invar 36 alloy part manufactured by CMT-WAAM with different strategies will have different mechanical properties, having a difference in ultimate tensile strength of 54 MPa and 142 MPa, and in elongation of 7% and 10% in building direction and perpendicular direction, respectively, between the most and the least resistant zone.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This research work was supported by the Basque Government (Departamento de Desarrollo Económico e Infraestructuras, Programa ELKARTEK) through the REIMAGIN project (grant KK-2023/00096). And financed by the CDTI and the European Union—NextGenerationEU and supported by the Ministerio de Ciencia e Innovación within the project “MADISON—MANUFACTURA ADITIVA, DIGITALIAZACIÓN Y SOSTENIBILIDAD”, approved within the framework of the call “Programa Cervera para Centros Tecnológicos 2023″ with Grant Agreement EXP—00163686 / CER-20231012”

    Effects of water temperature on growth, health and digestive processes of the thicklip grey mullet Chelon labrosus

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    This study aimed to identify the effects of water temperature on the rearing of the omnivorous teleost Chelon labrosus and to determine the optimal temperature for the culture of this interesting candidate for the diversification of European aquaculture. The fish (initial weight 26.81 ± 6.2 g) were held at four water temperatures (18, 22, 26 and 30 °C) in triplicate for 90 days in 100 L recirculating tanks (n = 14 / tank). The effects of said temperatures were assessed on growth, intestinal health and the digestive processes of the fish. At 18 °C, energy consumption was low, leading to a high accumulation of reserves and slow growth, a typical overwintering strategy. The best growth results were obtained at 22 °C, followed closely by 26 °C, which resulted in low energy reserves. The fact that the fish at 26 °C grew less than the ones at 22 °C while having similar energy consumption, suggested that this temperature was close to the end of the optimal range, but no signs of stress were detected. However, at 30 °C the fish had lower energy reserves but grew significantly less, which can be considered indicative of stress. Health impairment at this temperature was confirmed by the epithelial lesions found in this group. The growth and energy availability of the different groups is discussed in the light of the activities of α-amylase, pepsin and alkaline proteases. As an integration of all these results, a quadratic regression model resulting from growth values (SGR) in relation to water temperature was performed, and it allowed predicting an actual optimal water temperature of 22.8 °C for growth of C. labrosus. This is the first assessment of the optimal water temperature for the culture of C. labrosus, and it will be highly valuable for the development of its intensive culture.This research was funded by the Basque Government [00007-INA2019–33, 00003-INA2022–33, 00010-PIT2020–22, 00005–2,101,022,023, GIC19/IT-1302-19]. Markel Sanz-Latorre had a predoc contract financed by the Basque Government (IKERTALENT grant Programme

    Broad table-like magnetocaloric effect in the full hydrogen liquefaction range in Gd3Ni6XY

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    Gd3Ni6SiAl, Gd3Ni6SiGa, and Gd3Ni6AlGa (Ce3Ni6Si2-type, Im-3m, N 229, cI44) present a broad table-like magnetocaloric effect in the full hydrogen liquefaction range (20–77 K) with a real plateau wide enough to be competitive for refrigeration devices based on the Ericsson cycle. The characterization of the magnetocaloric variables (|ΔSMpk|= 6.60 J/kgK, TEC(10)= 6.44 J/kgK for Gd3Ni6SiGa, |ΔSMpk|= 6.05 J/kgK, TEC(10)= 6.01 J/kgK for Gd3Ni6SiAl, all at μ0ΔH=5 T) state that they are among the best of table-like magnetocaloric materials in this temperature range. The physical origin of this smooth and wide table-like effect is the combination of a spin reorientation transition (which appears in Gd3Ni6XY when Si or Ga is introduced) with the paramagnetic to ferromagnetic transition, close to each other. The application of the Banerjee criterion and the evolution of the critical exponent with temperature n(T) confirm that both transitions are second order, which is extremely relevant for real applications. From the study of the magnetic properties it has been inferred that the introduction of Si induces a magnetic ground state with combined ferromagnetic and antiferromagnetic components which turns to fully ferromagnetic at very low field. The critical exponents (β, γ, δ, n) have been found for the paramagnetic to ferromagnetic transitions; the values of γ (from 1.22 to 1.36) suggest that the magnetic interactions are short-range, though the ensembles do not correspond to any particular universality class.This work has been supported by Departamento de Educación del Gobierno Vasco (project IT1430–22) and from M.V. Lomonosov Moscow State University Program of Development. The authors thank for technical and human support provided by SGIker of UPV/EHU, specially the fruitful discussions with Dr. I. Orue

    Euskarazko bat-bateko bertsoen erritmoa. Silabatzea, erritmo-ereduak eta taldekatzea

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    855 p.Euskarazko bat-bateko bertsoen erritmoa da tesi honetan aztergai. Euskaraz sorturiko kantu inprobisatuanalor musikalari erreparatu zaio hizkuntzaren erritmo-antolakuntzaren fonologiarekiko loturetatik. Hirudira lanaren helburu nagusiak: 1) Euskararen tipo erritmikoak eta, zehatzago, euskararen fonologiakbertso-jarduna nola baldintzatzen duen aztertzea. 2) Hizkuntzaren, metrikaren eta musikaren artekoharremanak bertsoetan zer-nolakoak diren ulertzea. 3) Bertsoetako aldakortasun prosodikoaren nondiknorakoakaztertzea, testu-uztartzeaz gaur egun dagoen ikuspegia konplexuagotuz.Horretarako, marko teoriko eta interpretatibo baten lehen ardatzak proposatu dira, batetik, bat-batekobertsoen erritmo-antolakuntzaren funtsa ulertzeko heldulekuak eskaini asmoz. Lanketa horren osagarri,corpus azterketan oinarritu da lanaren alderdi enpiriko-analitikoa: 1980-2017 bitarteko BertsolariTxapelketa Nagusietako irabazleen finaleko bertsoak aztertu dira hizkuntzaren erritmoa egituratzen dutenbertsolarien silabatzeari, gauzatutako erritmo-ereduei eta unitate prosodikoei (taldekatzeari) erreparatuz.Egindako azterketan agerian geratzen da euskararen silaba-aldikotasuneranzko joera bertsoetako silabaegiturenmaiztasunetan, silaba-egitura baldintzatzen duten gertakari segmentaletan zein maiz hitz artekomugei ematen zaien trataeran, baita unitate prosodiko nagusien antolakuntzan ere.Edonola ere, badira hizkuntzaren tipo erritmikotik bete-betean azaldu ezin diren gertakariak.Hizkuntzaren, bertso-neurriaren eta doinuaren arteko elkarreraginak ahalbidetzen du bertsoetako txertatzeprosodikoa modu osoagoan ulertzea. Bertsolarien erritmo-ereduen zein taldekatzearen joera nagusiakbaldintza metriko-musikaletatik ulertu ahalko dira, baita gertakari segmental eta silabiko zenbait ere.Hizketa-mailak, epai-irizpideak (eta horien oinarrian dagoen bertsogintzari buruzko ikuskerak), garaiangaraikobertsogintza kanonak eta bertsolari bakoitzaren ezaugarri estilistikoak ere kontuan hartubeharreko eragileak direla uzten du agerian eginiko analisiak

    Adolescents and negligent social media use

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    Digital technology has evolved very quickly in a very short space of time, to the point at which it is now a personal technology that manages the information and communications of users who access the different services offered over the Internet - users who are increasingly younger and at greater risk. Negligent technology use is understood as use linked to the management of social media accounts and mobile apps that, while not intentionally harmful, may nevertheless place the user and/or others at risk. The study of negligent digital technology use during adolescence is vital to preventing risk behaviours through education. These types of behaviours range from anxiety to cyberbullying, device addiction, problems with self-perceptions of one’s own body and depression, among others. In this context, the aim of the present study is to analyse negligent digital technology use among adolescents on social media, and to explore the perceptions of this population group regarding the seriousness of these actions and the possible relationship between the two variables. Participants were 2529 students aged between 10 and 17 years from seven regions in southern Europe spread across three countries (Spain, Italy and Greece). The instrument used to collect the data was an ad hoc questionnaire designed to measure, among other things, actions indicating negligent use, excessive use of social medial and perceptions of the seriousness of such social media behaviour. The results reveal that the most negligent actions arried out by minors are: arranging to meet people they met on a social media site; displaying personal information in their account; and giving their passwords to people other than their parents and/or teachers. The results also indicate that adolescents engage in those negligent actions that they perceive to be less serious more assiduously, and carry out those they perceive to be more serious more sporadically. One of the principal findings was the increase in negligent use among older adolescents, which suggests that education in this field needs to begin much earlier, ideally before the age of 12 years.Ministerio de Ciencia, Innovación y Universidades. Ref.: PID2020-113918GB-I00/AEI/10.13039/50110001103

    Ácidos grasos de cadena corta y enfermedades neurodegenerativas

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    TFG de revisión bibliográfica cuyo objetivo consta de la comprensión del rol de los AGCC, su asociación a los procesos neurodegenerativos, su análisis químico y las posibles estrategias para regular estos elementos en el organismo con fines beneficiosos en la salud del individuo

    Autoimmune inflammation triggers aberrant astrocytic calcium signaling to impair synaptic plasticity

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    Cortical pathology involving inflammatory and neurodegenerative mechanisms is a hallmark of multiple sclerosis and a correlate of disease progression and cognitive decline. Astrocytes play a pivotal role in multiple sclerosis initiation and progression but astrocyte-neuronal network alterations contributing to gray matter pathology remain undefined. Here we unveil deregulation of astrocytic calcium signaling and astrocyte-to-neuron communication as key pathophysiological mechanisms of cortical dysfunction in the experimental autoimmune encephalomyelitis (EAE) model of multiple sclerosis. Using two-photon imaging ex vivo and fiber photometry in freely behaving mice, we found that acute EAE was associated with the emergence of spontaneously hyperactive cortical astrocytes exhibiting dysfunctional responses to cannabinoid, glutamate and purinoreceptor agonists. Abnormal astrocyte signaling by Gi and Gq protein coupled receptors was observed in the inflamed cortex. This was mirrored by treatments with pro-inflammatory factors both in vitro and ex vivo, suggesting cell-autonomous effects of the cortical neuroinflammatory environment. Finally, deregulated astrocyte calcium activity was associated with an enhancement of glutamatergic gliotransmission and a shift of astrocyte-mediated short-term and long-term plasticity mechanisms towards synaptic potentiation. Overall, our data identify astrocyte-neuronal network dysfunctions as key pathological features of gray matter inflammation in multiple sclerosis and potentially additional neuroimmunological disorders.This work was funded by the Instituto de Salud Carlos III (PI21/00629, to S.M. and A.R.-A; CB06/05/00, to C.M.) and cofounded by the European Union, Basque Government (PIBA_2023_1_0046; 2023111031; IT1473-22, to S.M.; IT1203-19, to C.M.), ARSEP Foundation (ARSEP - 1310 to S.M. and G.M.), INSERM (to G.M.), the European Research Council (MiCaBra, ERC-2017-AdG-786467, to G.M.), Fondation pour la Recherche Medicale (FRM, DRM20101220445 to G.M.), Region Aquitaine (CanBrain, AAP2022A-2021-16763610 and -17219710 to G.M.); French State/Agence Nationale de la Recherche (HippObese, ANR-23-ce14-0004-03; ERA-Net Neuron CanShank, ANR-21-NEU2-0001-04, to G.M), La Caixa Research Health 2023 (PsychoCannabis, HR23-00793, to G.M.), Spanish Ministry of Science and Innovation (PID2019-109724RB-100 to C.M.; PGC2018-093990-A-I00, to E.S.-G.), National Institutes of Health-MH (MH, R01MH119355; NINDS, R01NS097312; NIDA, R01DA048822, to A.A.), Postdoctoral and Predoctoral Programs of the Basque Government (to A.M.B., T.C. A.M.-G., and C.U), Predoctoral Program of the UPV/EHU (to E.S.)

    The Impact of Referencing Academics Who Have Defended and Exercised Pederasty

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    The scientific literature has shown an increasing demand by citizens and society at large to stop using people who have committed sexual violence against children as a reference in academia. However, research has not explored the fact that in some sectors of society, the rejection of individuals who have exercised sexual abuse against children is entirely deliberate. This study analyzes, for the first time, the incoherence of many academics when it comes to their positioning regarding different renowned authors who commit sexual abuse against children, and the consequences of such incoherence according to several citizens. To that end, social media analytics and interviews with 16 individuals aged 27 to 70 years from different professions, including university professors, construction workers and retired lawyers, were conducted. The results show three main consequences of the incoherence of academics who use as a reference authors who have defended and exercised pederasty: promoting social mistrust toward those academics, as there is no coherence between what they say and do; normalizing and promoting pederasty and impunity toward abusers, creating a sense that “anything goes”; and silencing and revictimizing victims, which creates a context of great vulnerability to develop a healthy sexuality

    El duelo y la masculinidad respetable en España y Cuba. Una cuestión de honor (siglos XIX y XX)

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    509 p.Esta tesis doctoral estudia de forma comparativa la construcción de la masculinidad normativa entre las clases medias y altas en la España y la Cuba de los siglos XIX y XX a través del análisis de los duelos y el honor. Los duelos constituyeron una práctica violenta empleada por los varones de la élite social para solucionar los conflictos en que su honor se hallaba en juego. Debido a que el concepto del honor masculino constituía un elemento crucial de la masculinidad normativa de las clases acomodadas, el estudio de los desafíos constituye una vía privilegiada para el conocimiento de esta identidad de género en todas sus dimensiones. Asimismo, esta tesis se interesa por la concepción de la feminidad de las clases medias y altas implicada en los lances, la cual, a su vez, se encontraba estrechamente vinculada con la noción del honor femenino. Por otro lado, el presente estudio toma en consideración esa perspectiva a menudo denominada interseccional, poniendo a trabajar simultáneamente las categorías de género, clase, raza y nación en su evolución en el tiempo

    Energy investigation of a semi-detached residence in middle Sweden: a study on household ventilation, energy balance and potential energy efficiency measures

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    Nordic houses have extended heating demand periods due to their climatology,in addition to some of the highest electricity consumptions in Europe. In Sweden, the residential sector accounts for 40% of the energy end use, and as such, it is imperative to evaluate plausible energy efficiency measures both in old and new buildings should the latest European Union regulations be met.Particularly, energy auditing practices are a step towards proposing robust changes. This work conducts an energy investigation over a semi-detached light-concrete house built in 2007, located in the municipality of Gävle in Middle Sweden. The study consists of several visits to conduct experimental measures in the ventilation system and indoor thermal conditions to map out the energy inflows and outflows of the dwelling. Results are contrasted with a simulated model using IDA-ICE software and the proposed energy efficiency measures are backed up with existing literature. The results indicate that the house is proficiently insulated with transmission losses in the order of 12 000 kWh/year and its mechanical exhaust ventilation system regulated well enough to comply with indoor air quality standards above 0.35 L/(s·m2), yet the overall energy demand remains above policy targeted levels. Measures like indoor temperature control and the implementation of heat recovery in the ventilation system are analyzed. In addition, a 5 kWp PV system is designed to help alleviate electricity needs from the grid. Some alternatives, however, proved to be insufficiently appealing from an investment standpoint as in the case of thermal collectors. The measures report potential energy savings of 26% over the base model, with financial benefits of over 7 800 SEK/year, though with hefty investments with payback periods close to a decade. This thesis ultimately aims to improve upon the energetic balance of its study dwelling, and it intends to contribute to the domestic energy auditing practices in a broader scope. Future work remains to be performed in the form of the development of more accurate auditing techniques for the removal of complex to meter variables that tend to fall under simplified assumptions

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