Repositório Institucional da Universidade Estadual da Paraíba
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Self-assembly of a supramolecular spin-crossover tetrahedron
No full textSpin-crossover (SCO) compounds are fascinating switchable
materials with great potential for the development of novel
technological devices. These coordination complexes exhibit
metal ions with two possible electronic configurations (low-
spin, LS, and high-spin, HS) which can be toggled using exter-
nal stimuli such as temperature, pressure, or light
irradiation. The different magnetic, optical, and structural
features of the two states allow these materials to be exploited
for a wide range of applications, such as sensors, actuators,
or for information storage. Interestingly, the physical pro-
perties of SCO compounds can be tuned by modifying the
weak non-covalent interactions exhibited within or in between
their molecular entities. In host–guest systems, these inter-
actions offer a versatile tool, for example, for manipulating the
transition temperature of encapsulating SCO complexes simply
by altering the nature of the supramolecular guest, as shown
in dinuclear helicates, tetrahedral cages, or cubic architec-
tures. Long range intermolecular interactions can be
exploited as well to tune or even to activate/deactivate the SCO
behaviour. Such modulation arises from the nature and
strength of such interaction, which influence the communi-
cation between molecules and thus its cooperativity, or
affect the ligand field exerted by the donor set and therefore
the SCO temperature
En recuerdo de Ramón Bayés: unas notas para un editorial de Psicooncología
No full textLa trayectoria académica de Ramon Bayés está indisolublemente ligada a la Universitat Autònoma de Barcelona. Desde allí, y cuando la Psicología era todavía una rama de la Licenciatura en Filosofía y Letras, comenzó a interesarse por la Psicología de la Salud a principios de los años 80. Pero lejos de centrarse en un único aspecto, decidió abarcar diferentes problemáticas y situaciones. Hacia ellas orientaba las tesis doctorales que dirigía. Era capaz de fusionar los intereses personales de cada doctorando o doctoranda con aquellos ámbitos de la atención sanitaria que planteaban cuestiones relevantes a las que la Psicología podía hacer aportaciones significativas para aumentar los conocimientos en nuestra disciplina en temas relevantes para la sociedad, como ha sido el caso de la Psicooncología. En este campo fue uno de los pioneros en nuestro país con su libro Psicología Oncológica de 1985. Así, a partir de una o varias tesis en nuestro ámbito o en otros, Ramon Bayés establecía una línea de investigación que, una vez comenzada, dejaba para que la continuasen sus discípulos. Era el iniciador y el promotor, y, una vez asentada la línea de trabajo, dirigía su atención e intereses hacia nuevos horizontes, incorporando así nuevos doctorandos y nuevos conocimientos. Eso permite entender su trayectoria desde la Psicooncología al SIDA y, después, hacia los Cuidados Paliativos. Sin embargo, no perdía de vista los logros que había conseguido y seguía manteniendo actividad en las líneas que había iniciado, colaborando con aquellos y aquellas a quienes había dirigido la tesis, y generando nuevos contactos
Reglamento del servicio de préstamo del CRAI (2026)
No full textReglament del servei de préstec del CRAI de la Universitat de Barcelona aprovat per la Comissió de Biblioteques el 21 d’abril de 2005. Modificat i aprovat per la comissió de Biblioteques delegada del Consell de Govern el 25 de febrer de 2026.Podeu consultar les versions anteriors a: http://hdl.handle.net/2445/148285. Podeu consultar la versió en català a: http://hdl.handle.net/2445/127127Aquest Reglament té com a objectiu regular l’accés als recursos documentals i als espais i equipaments per a l’aprenentatge i la investigació als membres de la Universitat de Barcelona. Aquest objectiu es concreta en el préstec de documents, espais i materials del CRAI de la Universitat; de documents d’altres universitats membres del Consorci de Serveis Universitaris de Catalunya (CSUC) mitjançant el Servei de Préstec Consorciat (PUC), i de documents d’altres institucions per mitjà del Servei de Préstec Interbibliotecari. També té com a finalitat conservar amb les màximes garanties els fons bibliogràfics i documentals de la Universitat de Barcelona i, alhora, donar-los el màxim rendiment prioritzant-ne la consulta a la comunitat de la Universitat i proporcionant-ne l’accés a totes les persones autoritzades. Aquest Reglament s’estructura en articles i disposicions relatius al préstec convencional de documents, i es desenvolupa en normatives per al préstec d’equipaments, espais, préstec interbibliotecari i préstec per a exposicions. Contè 6 annexos:- ANNEX 1: Normativa del servei de préstec d'ordinadors portàtils als CRAI biblioteques de la Universitat de Barcelona.- ANNEX 2: Normativa d'ús de les sales de treball dels CRAI biblioteques de la Universitat de Barcelona.- ANNEX 3: Normativa del servei de préstec de càmeres i altres materials del CRAI Biblioteca d'Informació i Mitjans Audiovisuals.- ANNEX 4: Normativa de préstec d'obres del CRAI de la Universitat de Barcelona per a exposicions.- ANNEX 5: Normativa del servei de préstec interbibliotecari del CRAI de la Universitat de Barcelona
Sufficiency and necessity of influencers for digital collective memory: a study through combined IPMA
No full textPurpose – This study aims to demonstrate the causal effect that content disseminated by influencers has on the formation of collective memories that underlie digital environments.
Design/methodology/approach – This work integrated a recent methodological sequence called combined importance-performance map analysis (cIPMA) that suggests articulating the results of PLS-SEM, necessary conditions analysis and IPMA through a graph that consolidates the causal effects of necessity and sufficiency of the variables contemplated in the study
Novel Heteroleptic Iridium(III) Complexes Containing COUBPY Ligands for Effective Photoinduction of Ferroptosis for Cancer Therapy
No full textFerroptosis, a recently described form of regulated, nonapoptotic cell death mechanism, presents significant potential for cancer treatment, particularly when combined with photodynamic therapy (PDT). In this study, we report the synthesis and biological evaluation of a series of Ir-COUBPY complexes as novel photosensitizers (PSs) for effective cancer phototherapy. These complexes exhibit high stability under both dark and light conditions and are capable of photogenerating Type I and Type II reactive oxygen species (ROS), as well as photo-oxidizing NADH. Electron paramagnetic resonance (EPR) spectroscopy provided direct evidence of light-induced superoxide and singlet oxygen generation, confirming dual ROS pathways. Moreover, the Ir-COUBPY complexes preferentially accumulated in the mitochondria of cancer cells, leading to the photogeneration of hydroxyl radicals and hydrogen peroxide. Photocytotoxicity studies on HeLa and A375 cancer cells underscored the role of the COUBPY ligand in enhancing PDT efficiency upon irradiation with both green and red light. Among the Ir-COUBPY complexes, the most effective PS, Ir4a, was encapsulated in polyurethane−polyurea hybrid nanocapsules (NC-Ir4a), resulting in a significant increase in phototoxic index values (e.g., from 64 to 179.6 in A375 cells). Mechanistic studies confirmed ferroptosis as the primary cell death pathway induced by Ir4a, supported by light-dependent lipid peroxidation, glutathione oxidation and depletion, intracellular ATP photodepletion, and the viability-restoring effect of Fer-1. These effects were more pronounced upon nanoencapsulation. Photobiological studies with 3D tumor spheroids of A375 cells further confirmed higher cellular uptake of NC-Ir4a, contributing to improved phototoxic efficiency. Overall, these findings highlight the potential of coumarin-based COUBPY ligands in the design of new Ir(III)-based PSs that can be activated with light within the phototherapeutic window, operating through nonconventional cell death mechanisms such as ferroptosis
Genetic Risk for ADHD and Later-life Health and Wellbeing: Individual and Spousal Spillovers
No full textThe objective of this paper is twofold. First, we aim to provide evidence on the relationship between genetic predisposition to attention deficit hyperactivity disorder (ADHD) and later-life health outcomes. Additionally, we investigate cross-spousal spillovers on both physical and mental health associated with genetic risk for this condition. Leveraging rich data for individuals aged 50 + and their partners in England our findings indicate poorer general wellbeing, physical and mental health among older individuals with a higher genetic risk of experiencing ADHD. Moreover, these associations are substantially larger for older women and individuals who are unmarried, relatively less educated and less wealthy. Our results also show that male partner’s genetic risk for ADHD negatively affects the health of their female partners, whereas female genetic risk predisposition does not appear to affect the health of their male partners. Moreover, these adverse effects on women are stronger among those who are relatively less educated and live in relatively poorer households. Finally, we present a number of robustness tests which validate the reliability of our approach
Using Virtual Reality to Promote Self-Identity Reconstruction as the Main Focus of Therapy
No full textBased on the repertory grid technique, we developed Explore Your Meanings (EYME), a digital platform that helps patients explore identity values and internal conflicts using virtual reality (VR). EYME was part of a research project treating depression in young adults, including 10 weekly, 1-h sessions aimed at changing personal constructs—cognitive schemas that shape how individuals interpret reality. We present the case of Mary, a 21-year-old woman diagnosed with persistent major depressive disorder and social phobia. Early sessions with EYME revealed key implicit dilemmas in Mary's worldview, such as feeling that she had to be selfish (an undesired personal characteristic) to become smarter and more self-confident (desired pole). As Mary visualized these constructs in VR, she began to recognize her identity conflicts and strengths, ultimately helping her to improve her negative self-image. Interventions focused on reframing these constructs, particularly around “intelligence” and introducing “emotional intelligence,” which helped Mary adopt a more nuanced view of herself. A key session involved a two-chair dialog between her “critical” and “emotional” selves, facilitating the integration of polarized aspects of her personality. In subsequent sessions, EYME reinforced these changes, with Mary reinterpreting behaviors like being “selective” as protective rather than negative. By the end of therapy, she no longer met the criteria for depression or social phobia, and her psychological distress had normalized
Xylem anatomical and growth responses of the dwarf shrub <em>Vaccinium myrtillus</em> to CO<sub>2</sub> enrichment and soil warming at treeline.
No full textPlant growth responses to environmental changes may be linked to xylem anatomical adjustments. The study of such links is essential for improving our understanding of plant functioning under global change. We investigated the xylem anatomy and above-ground growth of the dwarf shrub Vaccinium myrtillus in the understorey of Larix decidua and Pinus uncinata at the Swiss treeline after 9 years of free-air CO2 enrichment (+200 ppm) and 6 years of soil warming (+4 °C). We aimed to determine the responses of xylem anatomical traits and growth to these treatments, and to analyse xylem anatomy–growth relationships. We quantified anatomical characteristics of vessels and ray parenchyma and measured xylem ring width (RW), above-ground biomass and shoot elongation as growth parameters. Our results showed strong positive correlations between theoretical hydraulic conductivity (Kh) and shoot increment length or total biomass across all treatments. However, while soil warming stimulated shoot elongation and RW, it reduced vessel size (Dh) by 14%. Elevated CO2 had smaller effects than soil warming: it increased Dh (5%) in the last experimental years and only influenced growth by increasing basal stem size. The abundance of ray parenchyma, representing storage capacity, did not change under any treatment. Our results demonstrate a link between growth and stem Kh in V. myrtillus, but its growth responses to warming were not explained by the observed xylem anatomical changes. Smaller Dh under warming may increase resistance to freezing events frequently occurring at treeline and suggests that hydraulic efficiency is not limiting for V. myrtillus growing on moist soils at treeline. Our findings suggest that future higher atmospheric CO2 concentrations will have smaller effects on V. myrtillus growth and functioning than rising temperatures at high elevations; further, growth stimulation of this species under future warmer conditions may not be synchronized with xylem adjustments favouring hydraulic efficiency
Novel metaphor processing in young autistic children
No full textThe purpose of this study is to explore possible differences between autistic and neurotypical (NT) children in novel metaphor comprehension. Much of the recent literature has related metaphor comprehension difficulties that autistic individuals exhibit to general linguistic abilities. In our design, we carefully pair-matched young autistic children (3.13 to 12.25 years of age) toNT controls (3.69 to 9.04 years of age) on verbal mental age and tested their metaphor interpretation abilities with a picture selection paradigm combined with eye tracking measures. We predicted differences in performance in both types of measures, although we foresaw autistic participants performing above chance in the picture selection task. However, results did not show a difference between groups in the picture selection task, which would favor accounts that relate metaphor interpretation to linguistic abilities in autistic population. Interestingly, the eye tracking observations revealed differences between groups concerning gaze movements in the region corresponding to the processing of the metaphoric vehicle. Such differences replicate those found in previous studies with similar designs, such as Vulchanova et al.’s (2019). On the other hand, the evidence presented and discussed in the paper does not suggest either impairment or delay with respect to metaphor processing. Rather, the evidence only suggests differences. While the source of such processing differences is still unknown, the results of the current study cast some doubts the idea that the main factor in metaphor processing in the autistic population is their structural language level.