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Non-destructive evaluation and characterisation techniques for lithium-ion battery degradation mechanisms via novel in operando and ex-situ approaches
No full text268 p.Non-destructive analytical techniques represent a key tool within the battery field, from fundamental research and development, through quality control and state-of-safety and state-of-health within proof-of-concept and commercial systems, to recycling and second life circular economy applications. While a range of analytical tools already exist, these often have limitations in the information they may provide or their applicability. Thus, expanding this toolkit through novel application methods represents an important step forward in the development of a comprehensive analysis of batteries and their constituent systems ¿ from first fabrication to end-of-life. Within this thesis, we examine the potential of non-destructive techniques when applied to hitherto unexplored area, from laboratory to cell level, providing an understanding of the advantages and limitations of these as tools for the battery community
Liqid crystals of the ferroelectric nematic realm: microscopic dynamics and phase transitions
No full text166 p.Liquid crystals are substances that constitute a state of matter whose properties are intermediate between those of conventional liquids and crystalline solids. Due to this dual nature, they exhibit a rich phenomenology, including the emergence of ferroelectricity. However, until recently, this property was restricted to liquid crystalline phases with partial positional order, such as smectic and columnar mesophases. The recent discovery of the ferroelectric nematic (NF) phase, a true three-dimensional ferroelectric liquid, has sparked significant interest and posed fundamental questions about how long-range polar order develops in such systems. Moreover, the discovery of other related polar mesophases has led to the notion of the "ferroelectric nematic realm".This thesis aims to shed light on some general aspects about the microscopic dynamics and phase transitions occurring in the ferroelectric nematic realm using broadband dielectric spectroscopy as a main tool, but complemented by optical and second-harmonic generation measurements, X-ray diffraction, and theoretical and computational methods. The two prototypical ferroelectric nematogens RM734 and DIO were studied, and their collective and molecular relaxation mechanisms interpreted, revealing that the colossal dielectric constants observed in the NF phase arise from extrinsic effects. Additionally, in another material, the study of the Iso¿NF phase transition provided valuable information regarding the dipole ordering mechanisms of NF systems. Also, for the SmAF phase, a mean-field molecular model was developed including polar interactions, and good agreement with experimental data was achieved. Finally, the dynamics in a series of phase sequences, some of them including the SmCHP phase, were studied. Regarding their pretransitional behavior in the N phase, it was found that the softening of the splay elastic constant depends on the width of the antiferroelectric NS phase. These results offer new perspectives on the dynamical behavior of these fascinating systems, and open new directions for advancing in the understanding of ferroelectric liquid crystals and their new potential technological application
Mitochondrial 3-hydroxy-3-methylglutaryl-coenzyme A synthase deficiency: From metabolism to clinical implications
No full textPurpose
Ketone bodies represent an important energy source and can contribute much to the energy supply of the brain. Mitochondrial 3-hydroxy-3-methylglutaryl-coenzyme A synthase deficiency (HMGCS2D) is an autosomal recessive disorder of ketogenesis caused by biallelic variants in HMGCS2. Only 59 patients with this disorder have been reported so far.
Methods
We performed a comprehensive literature search to identify all published cases of HMGCS2D (n = 59). Additionally, the data of 16 patients with this disorder who are yet undescribed were collected. Clinical course, biochemical findings, and mutation data are highlighted and discussed. An overview on all HMGCS2 variants reported in patients is provided.
Results
Sixty-eight patients (91%) presented with an acute metabolic decompensation, mostly within the first year of life but beyond the neonatal period. Asymptomatic individuals were identified in several families. Six patients (8%) had died, mainly during the initial metabolic crisis. The neurologic long-term outcome of surviving patients was favorable with almost all patients (98%) showing normal development. Only 1 variant was identified to be common, (HMGCS2) NM_005518.4:c.634G>A p.(Gly212Arg), and found in 6 families. No genotype-phenotype correlation can be established.
Conclusion
This comprehensive data analysis provides an overview on all published patients reported with HMGCS2D, including a list of HMGCS2 variants identified in affected individuals.Research of J.O.S is funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation), project numbers 514177501, 528562393-FIP26, and 538669957. J.d.l.H. acknowledges the Basque Government, Health Department contract for Intensification of Research Activities, Exp. No. 2023222005
Zigor askatasun-gabetzaileen alternatibak: Zigorra eteteari eta ordezkatzeari buruzko aipamen berezia
No full textGradu Amaierako Lan honek Espainiako ordenamendu penalean espetxeratzearen ordezko mekanismo gisa moduan, askatasunaz gabetzeko zigorrak eteteko eta ordezteko figura juridikoak aztertzen ditu. Doktrina eta jurisprudentzia azterlanaren eta datu enpiriko aktualizatuen bitartez, neurri horiek berrerortzearen prebentzioan eta birgizarteratzean duten eraginkortasuna aztertu nahi da, baita ere arlo juridikoan eta kriminologikoan eragin dituzten kritika nagusiak aztertu ere. Era berean, erakunde horien araudi-bilakaera eta auzitegiek izan duten aplikazio praktikoa jorratuko da, Espainiako Konstituzioaren 25.2. artikuluan ezarritako helburuak betetzen dituzten zehazteko.Gradu Amaierako Lan honek Espainiako ordenamendu penalean espetxeratzearen
ordezko mekanismo gisa moduan, askatasunaz gabetzeko zigorrak eteteko eta ordezteko
figura juridikoak aztertzen ditu. Doktrina eta jurisprudentzia azterlanaren eta datu
enpiriko aktualizatuen bitartez, neurri horiek berrerortzearen prebentzioan eta
birgizarteratzean duten eraginkortasuna aztertu nahi da, baita ere arlo juridikoan eta
kriminologikoan eragin dituzten kritika nagusiak aztertu ere. Era berean, erakunde horien
araudi-bilakaera eta auzitegiek izan duten aplikazio praktikoa jorratuko da, Espainiako
Konstituzioaren 25.2. artikuluan ezarritako helburuak betetzen dituzten zehazteko
Ameriketako Estatu Batuen eta Mexikoren arteko Merkaritza Libreko Akordioa(k): sorrera, bilakaera, ondorioak eta aurrera begirakoak
No full textIkerlan honek Ameriketako Estatu Batuak, Kanada eta Mexikoren arteko Merkataritza Libreko Akordioak (TLCAN) eta berau ordezkatu duen T-MEC akordioak Mexikon izandako eragina aztertzen du. Dena den, hitzarmena indarrean sartu zenean asko izan ziren Ameriketako Estatu Batuak akordiotik garaile aterako zela uste zutenak, Mexikoren kontrarako. Aurreko ideia baieztatu edo ukatzeko herrialde mexikarreko bi sektore estrategiko aztertuko dira, hala nola, autogintza eta nekazaritza sektoreak. Bi herrialdeen arteko hurbilketa historiko eta teoriko batetik abiatuta, TLCANaren sorrera, bilakaera eta garrantzia aztertzen da. Jarraian, kasuaren analisiaren bidez, bi sektore horien eboluzioa eta nondik norakoak ikertzen dira, sektore bakoitzaren errealitatea modu zehatzago batean deskribatzen duen adierazle desberdinak analizatuz. Azkenik, hasieran plazaratutako baieztapena egia edo okerra den ondorioztatuko da, analisiko informazioa baliatuz
Topological features of magnetically-ordered and correlated crystals
No full text212 p.Esta tesis se centra en el estudio de la topología de la estructura electrónica en materiales cristalinosque muestran un ordenamiento magnético de sus átomos y altas correlaciones. Mediamente métodosbasados en simetría cristalina, estudia diferentes fases y características topológicas como aislantestopológicos con efecto Hall cuántico anómalo de spin, líneas nodales y estados de superficie ensuperconductores basados en hierro. Introduce una nueva herramienta de software para analizar latopología en materiales magnéticos usando cálculos de primeros principios. Con esta nuevaherramienta, se analizan las líneas nodales protegidas por simetría especular en Fe3GeTe2 y Cohexagonal, que muestran la misma simetría en sus fases ferromagnéticas. Posteriormente, se estudianlas transiciones de fase topológicas en superconductores basados en hierro mediante dos métodosdistintos. En primer lugar, mediante el dopaje de FeSe con Te, del cual se presentan medidasexperimentales demostrando la presencia de estados de borde topológicos. En segundo, mediante esestrés uniaxial de FeSe, prediciendo la obtención de dos fases con topología Z2 fuerte y débil.Finalmente, se propone una extension de los métodos basados en simetría a sistemas con muy altascorrelaciones, en este caso el modelo de Kitaev en la red hexagonal en panal. En este caso, seidentifican fases topológicas de aislante tipo Chern obtenidas mediante un campo magnético externo
Repercusión emocional de la COVID-19 en la formación del profesorado
No full textLa actual sociedad globalizada reclama un nuevo perfil universitario acorde a las nuevas
demandas del mercado laboral. Esta transición entre los paradigmas pedagógicos se vio
acelerada a consecuencia del cierre inesperado de las universidades por la pandemia
del COVID-19. Este trabajo longitudinal analiza la repercusión emocional que los
cambios forzados por la pandemia han generado en el proceso formativo del alumnado
universitario. Desde un enfoque cualitativo, concretamente biográfico-narrativo, se han
analizado 55 relatos autobiográficos del alumnado (63,63% son mujeres y el 36,36%
hombres) de la Facultad de Educación y Deporte de la Universidad del País Vasco
(España). Los resultados resaltan el papel que ha desempeñado el uso de las TIC al
acortar la distancia en las relaciones y posibilitar la colaboración y cooperación entre el
profesorado y el alumnado. No obstante, el alumnado universitario aún presenta
dependencia respecto a las clases magistrales. Asimismo, la ansiada vuelta a la
presencialidad también les generó cierta inestabilidad emocional. En conclusión, a pesar
de que las crisis mundiales como la recientemente experimentada puedan suponer
oportunidades para repensar los modelos de enseñanza-aprendizaje, en la nueva
Revista Electrónica de Investigación Educativa, Online First / IIDE-UABC 2
normalidad no se aprecian cambios metodológicos considerables respecto a las
relaciones sociales y emocionales
Quantum magnetism in systems with SU(N) symmetry and magnetic impurities in superconductors
No full text172 p.Magnetic phenomena in systems exhibiting superconductivity, quantumimpurity interactions, and exotic phase transitions present a richdomain for theoretical exploration. This thesis synthesizesinsights from several studies investigating these areas:1. The interplay between superconductors (SC) and ferromagneticinsulators (FMI) reveals novel correlations, where the FMI inducesspin polarization at the SC surface through the magnetic proximityeffect. This effect is further examined via Kondo coupling tomagnetic impurities, demonstrating energy splitting in fermionparitystates linked to Ruderman-Kittel-Kasuya-Yosida (RKKY)-likeinteractions and spin-triplet correlations. Numericalrenormalization group (NRG) and perturbative analyses establish ascaling relationship between this splitting and the Kondotemperature relative to the superconducting gap.2. Quantum spin-1/2 impurities coupled to s-wave superconductorsare analyzed using large- mean-field theory, which proveseffective in the strong-coupling regime T_K > . This methodaccurately predicts Yu-Shiba-Rusinov subgap states, their spectralproperties, and local density profiles, complementing NRGtechniques and extending to more complex impurity models.3. We propose to utilize two spin-1/2 imputiries on asuperconducting bath as a quantum qubit. This can be realized witheither quantum dots or triangulene spin-1 Heisenberg chain onsuperconducting surface. An effective two level model is proposedto describe the dynamics and validated by time-dependent NRG.4. In SU(>2)-symmetric Fermi gases, the ferromagnetic phasetransition is shown to be first-order, in line with Landau's meanfieldpredictions. Unrestricted Hartree-Fock calculations andbeyond-mean-field corrections illustrate the role of magneticfluctuations, which amplify the abruptness of the transition andenhance full polarization tendencies in the gas.5. Investigating lightly-doped multilayer graphene with ageneralized four-component spin model reveals density-driven phasetransitions. While Hartree-Fock methods predict cascadingtransitions, incorporation of correlation energies via the randomphaseapproximation simplifies these to a single transitiongoverned by the interplay of exchange and correlation energies.These findings elucidate the phase behavior of multilayer grapheneand extend to similar symmetry-broken electron gas systems.This amalgamation highlights the universality and diversity ofmagnetic transitions and interactions, spanning superconductors,Fermi gases, and layered graphene systems, thereby offering afoundation for future theoretical and experimental studie
Association of environmental noise exposure with cortisol levels in children from eight European birth cohorts
No full textEl ruido ambiental es un importante factor de riesgo ambiental para la salud pública. De acuerdo con el modelo de reacción al ruido, la liberación de hormonas del estrés como el cortisol en respuesta a la exposición al ruido, desempeña un papel clave en el desarrollo de los efectos sobre la salud inducidos por el ruido. Nuestro objetivo fue estudiar la asociación entre el ruido ambiental con los niveles agudos (UCC) y acumulados (HCC) de cortisol en niños de 5 a 12 años de edad. Para ello, se analizaron datos de la cohorte HELIX –con datos de spot UCC– y de las cohortes Generación R e INMA (Gipuzkoa y Sabadell) –con datos de CHC. La muestra analítica involucrada: 750 niños HELIX (edad media = 7.75), 1326 niños de la Generación R (edad media = 6.06), 111 niños INMA-Sabadell (edad media = 8.75) y 288 niños INMA-Gipuzkoa (edad media = 7.85). La exposición al ruido ambiental equivalente día-tarde-noche (Lden) durante el año de seguimiento se estimó en las direcciones de los participantes, utilizando los mapas de ruido existentes. Se usaron gráficos acíclicos dirigidos (DAG) para identificar covariables apropiadas y reducir la posibilidad de estimación sesgada. Se utilizó el modelado de efectos mixtos y el modelado lineal para examinar la asociación entre Lden y la concentración de cortisol mediante análisis de casos completos. Ninguno de los modelos alcanzó la significación estadística. No se observó correlación entre el CHC y la UCC en los participantes del INMA-Sabadell, para quienes se disponía de datos de cortisol tanto urinario como capilar. La investigación futura debería dar prioridad a la investigación de los efectos del ruido ambiental en el CHC, ya que puede servir como un indicador más fiable para evaluar las asociaciones con exposiciones crónicas. Además, los estudios futuros sobre los efectos de salud inducidos por el ruido en los niños deben incorporar otros biomarcadores de estrés e inflamación crónica para proporcionar una comprensión más completa de estas asociaciones.Environmental noise is a major environmental risk factor for public health. According to the noise reaction model
the release of stress hormones like cortisol in response to noise exposure, plays a key role in the development of
noise-induced health effects. We aimed to study the association between environmental noise with both acute
(UCC) and cumulative (HCC) cortisol levels in children 5–12 years of age. To do so, we analysed data from the
HELIX cohort –with spot UCC data- and from the Generation R and INMA cohorts (Gipuzkoa and Sabadell) –with
HCC data. The analytical sample involved: 750 HELIX children (mean age = 7.75), 1326 Generation R children
(mean age = 6.06), 111 INMA-Sabadell children (mean age = 8.75) and 288 INMA-Gipuzkoa children (mean age
= 7.85). Day-evening-night equivalent (Lden) environmental noise exposure during the year of the follow-up was estimated in the addresses of participants, using existing noise maps. Directed acyclic graphs (DAGs) were used to identify appropriate covariates and reduce the chance for biased estimation. We used mixed-effects modelling and linear modelling to examine the association between Lden and cortisol concentration using complete case analyses. None of the models reached the statistical significance. We observed no correlation between HCC and UCC in INMA-Sabadell participants, for whom both urinary and hair cortisol data were available. Future research should prioritize investigating the effects of environmental noise on HCC, as it may serve as a more reliable indicator for assessing associations with chronic exposures. Additionally, future studies on noise-induced health effects in children should incorporate other biomarkers of stress and chronic inflammation to provide a more comprehensive understanding of these associations.The authors of this paper want to show their great gratitude to all the children and parents participating in all the cohorts included in this project: Born in Bradford (BiB, UK), ´Etude des D´eterminants pr´e et postnatals pr´ecoces du d´eveloppement et de la sant´e de l’ENfant (EDEN, France), INfancia y Medio Ambiente (INMA Sabadell and INMA Gipuz
koa, Spain), the Kaunas birth cohort (KANC, Lithuania), The Norwegian Mother, Father and Child Cohort Study (MoBa, Norway), the Rhea mother-child cohort (Greece) and Generation R (Netherlands). We thank Ingvild Ess´en for thorough field work and Heidi Marie Nordheim for biological sample management in the MoBa cohort, and the MoBa administrative unit. We are grateful to all the participating families in Norway who take part in this on-going cohort study (MoBa).The
tute for Global Health (ISGlobal) acknowledges support from grant CEX2023-0001290-S funded by MCIN/AEI/10.13039/501100011033, and support from the Generalitat de Catalunya through the CERCA Program. The authors acknowledge that Born in Bradford is only possible because of the enthusiasm and commitment of the children and parents in Born in Bradford. We are grateful to all participants, health professionals and researchers who have made Born in Bradford happen. The authors acknowledge also Noemi Haro too, who performed the technical part of the cortisol analysis at Hospital del Mar Research Institute. Finally, AA would also like to thank the Department of
cation, Language Policy and Culture of the Government of the Basque Country for a predoctoral research training grant (PRE_2020_1_0182)
Joseba Sarrionandiaren poesia (1981-2016). Ideia literario eta praktikasortzailearen lorratzak
No full text792 p.Tesiaren ikerketaren helburua Joseba Sarrionandiaren poetika eta praktika sortzailea aztertzea da, haren bilakaerari arreta eskainiz. Horretarako, egilearen idazlanak aztertu dira, semiotika, aldaeren kritika eta kritika genetikoaren laguntzaz. Irizpide metodologiko horien ildoan, idazketa prozesu amaigabetzat ulertzen da, eta testuek denboran izandako aldaerak aztertu dira, haien irakurketa eta interpretazio sinbolikoarekin batean. Idazlearen poesia liburu guztiak aztertzeaz gain, egileak eskuzabalki emandako hiru aurre-testu ikertu dira, eta, horiei esker, obraren ezagutza bide berriak ireki dira. Ikerlanaren emaitza gisa, egilearen idazlanaren bilakaerari buruzko ikuspuntu berriak eskuratu ahal izan dira. Hala, Ni ez naiz hemengoa liburuaren aurre-testuen eta edizioen azterketaren bidez, egilearen ideia poetikoei buruzko ikuspuntu sakona eskuratu da, zeinak idazleak geroago adierazitako ideiekin alderatuz, bilakaera identifikatzeko balio duen. Bestalde, Sarrionandiaren ibilbide poetikoan hiru urrats bereizi dira: 1) Izuen gordelekuetan barrena trantsizio garaiko neobangoardiaren emaitza adierazgarrienetakoa; 2) kartzela eta militantzia gaiei atxikitako idazlanen zikloa (Intxaur azal baten barruan/Eguberri amarauna, Marinel zaharrak eta Kartzelako poemak); 3) Hnuy illa majah yahoo eta Hilda dago poesia? liburuak. Ibilbide horretan ildo tematiko eta sinbolikoak identifikatu dira, haien tratamendua eta adierazpenaren lanketaren bilakaera hautemanez. Bestalde, aurre-testuetatik edizio argitaratuetara, eta edizioz edizio egindako moldaketen ondorioz, zenbait irizpide nagusi identifikatu ahal izan dira, eta aldaketen zioei buruzko hipotesiak eraiki dir