An unusual self-assembly pattern is observed for highly ordered 1500-nm-thick films of monodisperse 13-nm-sized colloidal PbSe quantum dots, originating from their faceted truncated cube-like shape. Specifically, self-assembled PbSe dots exhibited attachment to the substrate by <001> planes followed by an interconnection through the {001} facets in plan-view and {110}/{111} facets in cross-sectional-view, thus forming a cubic superlattice. The thermoelectric properties of the PbSe superlattice thin films are investigated by means of frequency domain thermoreflectance, scanning thermal probe microscopy, and four-probe measurements, and augmented by computational efforts. Thermal conductivity of the superlattice films is measured as low as 0.7 W m−1 K−1 at room temperature due to the developed nanostructure. The low values of electrical conductivity are attributed to the presence of insulating oleate capping ligands at the dots’ surface and the small contact area between the PbSe dots within the superlattice. Experimental efforts aiming at the removal of the oleate ligands are conducted by annealing or molten-salt treatment, and in the latter case, yielded a promising improvement by two orders of magnitude in thermoelectric performance. The result indicates that the straightforward molten-salt treatment is an interesting approach to derive thermoelectric dot superlattice thin films over a centimeter-sized area.

[Excerpt] Having appeared at the end of the seventeenth century, the calculus (differential and integral calculi for Leibniz, method of fluxions for Newton) was un doubtedly the most important branch of pure mathematics in the eighteenth century. This importance was recognized at the time: “one of the most wonderful inventions in mathemat ics, which not only raised geometry almost to its high est peak, but also expanded the other disciplines to such an extent that one would have to write entire books if one wanted to specify the benefits of this calculus” [Zedler, 1731–1754, vol. 5, col. 190]. “Of all the discoveries that have ever been made in the sciences, there is none as important, nor as fruitful in applications, as that of infinitesimal analysis” [Bossut, 1784, lxxii]. [...]

Polymer biomaterials are being considered for tissue regeneration due to the possibility of resembling different extracellular matrix characteristics. However, most current scaffolds cannot respond to physical-chemical modifications of the cell microenvironment. Stimuli-responsive materials, such as electroactive smart polymers, are increasingly gaining attention once they can produce electrical potentials without external power supplies. The presence of piezoelectricity in human tissues like cartilage and bone highlights the importance of electrical stimulation in physiological conditions. Although poly(vinylidene fluoride) (PVDF) is one of the piezoelectric polymers with the highest piezoelectric response, it is not biodegradable. Poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) is a promising copolymer of poly(hydroxybutyrate) (PHB) for tissue engineering and regeneration applications. It offers biodegradability, piezoelectric properties, biocompatibility, and bioactivity, making it a superior option to PVDF for biomedical purposes requiring biodegradability. Magnetoelectric polymer composites can be made by combining magnetostrictive particles and piezoelectric polymers to further tune their properties for tissue regeneration. These composites convert magnetic stimuli into electrical stimuli, generating local electrical potentials for various applications. Cobalt ferrites (CFO) and piezoelectric polymers have been combined and processed into different morphologies, maintaining biocompatibility for tissue engineering. The present work studied how PHBV/CFO microspheres affected neural and glial response in spinal cord cultures. It is expected that the electrical signals generated by these microspheres due to their magnetoelectric nature could aid in tissue regeneration and repair. PHBV/CFO microspheres were not cytotoxic and were able to impact neurite outgrowth and promote neuronal differentiation. Furthermore, PHBV/CFO microspheres led to microglia activation and induced the release of several bioactive molecules. Importantly, magnetically stimulated microspheres ameliorated cell viability after an in vitro ROS-induced lesion of spinal cord cultures, which suggests a beneficial effect on tissue regeneration and repair.

Acknowledging their sociocultural relevance and the exceptional affordances they offer, lifestyle magazines are part of a long-lasting, globalised, and hegemonic industry. Released or inspired by the United States of America and the United Kingdom, many of them tend to follow or get inspired by their editorial and representational trends. Literature reveals how racialised people appear less frequently and with specific dehumanising contours on the various media outlets, including this semiotic genre, of which examples are 'Women’s Health' and 'Men’s Health' magazines. To understand how hegemonic whiteness is promoted by these lifestyle magazines, this article presents a study of their main covers, employing multimodal critical discourse analysis. Intersectionality theory and decolonial studies inform this analytical approach. Considering a body of literature, through cover participants and semiotic resources altogether, whiteness, racialised sexual objectification, racial privilege, and strategic fitnessist appendix are the main detected discourses. These allow the unveiling of a colonial eye. This chapter ends by raising questions in a discussion and recommending a more careful approach to diversity and media.

Os lípidos constituem uma porção significativa do cérebro e desempenham um papel crítico na sua função e estrutura, com alterações lipídicas importantes observadas em doenças neurodegenerativas, como a doença de Alzheimer (AD), em que os estudos implicam a via da fosfolipase D (PLD). A isoenzima PLD1 da PLD foi demonstrada ser a principal fonte de ácido fosfatídico no hipocampo, uma estrutura cerebral vulnerável à degeneração no contexto neuropatológico. Além disso, foi demonstrado que a sua ablação perturba a organização do hipocampo, afetando particularmente o lipidoma do hipocampo dorsal (DH), bem como a diferenciação da arborização dendrítica nos neurónios piramidais de CA1. Esta descoberta implica o papel da PLD1 na manutenção da estrutura do hipocampo. Dada a importância de compreender o contexto celular da atividade da PLD1 na integridade neuronal do hipocampo, surgiu a necessidade de caraterizar histologicamente as diferentes populações de células gliais no hipocampo, tanto na presença como na ausência de PLD1, bem como os processos dependentes da PLD1 nestas mesmas células. A compreensão da relação entre os neurónios e as células gliais - especificamente os oligodendrócitos e os astrócitos - na garantia da integridade neuronal através da via da PLD1 forneceria informações valiosas sobre os mecanismos celulares subjacentes à função hipocampal. No entanto, abordagens prévias não captaram totalmente a extensão da atividade da PLD1, suscitando a necessidade de métodos que não só quantifiquem a atividade da PLD1, mas também a avaliem a nível celular e subcelular. O presente estudo apresenta os desafios da aplicação de uma abordagem desenvolvido pela nossa equipa com base no método IMPACT, revelando que, embora a incubação ex vivo com 5-hexyn-1-ol tenha melhorado a distribuição espacial do álcool, o sinal inespecífico salienta a necessidade de otimizações adicionais. A análise histológica da região CA1 do DH implica que a ablação da PLD1, embora não influencie a densidade populacional de astrócitos e oligodendrócitos, afeta negativamente a sua maturação. Além disso, a ablação de PLD1 parece perturbar os processos de mielinização no CA1 do DH. Estes resultados abrem perspetivas para uma caraterização mais aprofundada da estrutura morfológica dos astrócitos e dos oligodendrócitos para compreender a extensão do papel que a PLD1 desempenha na diferenciação destas células e, em última análise, na proteção da integridade neuronal.

Evaluating the biomedical potential of marine biopolymers is a promising strategy for their high-value application. This study investigated the ability of collagen derived from Chondrosia reniformis to support cell proliferation and chondrogenic differentiation, assessing its suitability for tissue regeneration. Collagen was isolated, preserving its fibrillar structure and glycosylation features, then cross-linked with EDC, genipin, or glutaraldehyde to produce freeze-dried scaffolds. The resulting structures were characterized in terms of physicochemical properties, morphology, degradation, rheology, and cytocompatibility. While all scaffolds showed comparable degradation and rheological behavior, genipin-cross-linked scaffolds exhibited larger pore sizes, whereas glutaraldehyde-cross-linked scaffolds showed higher water uptake. In vitro assays using ATDC5, BJ, and EA.hy926 cell lines demonstrated superior metabolic activity and proliferation on genipin-cross-linked scaffolds. Additionally, human adipose stem cells displayed early chondrogenic differentiation, evidenced by SOX9, ACAN, and COMP expression under basal conditions. These findings highlight the versatility of C. reniformis collagen for biomedical applications, particularly cartilage regeneration.

Leaders have a critical role in promoting working conditions that actively consider the health and wellbeing of employees. Therefore, studying the impacts leadership produce at work is key. This study analyzes the relationship between leadership and conflict management styles, specifically examining how followers’ perception of managers’ leadership readiness relates to their perception of managers’ conflict management styles. The study included 185 participants (67.6% men; 28.1% women), all employees of a metalworking company, with ages between 19 and 67 years old (M = 38.14; SD =10.94). It was evaluated leadership (cycles, styles, and antecedent factors) and conflict management styles. The results showed that: (a) followers perceived that managers should turn clearer their leadership philosophy, practice, and criteria; and (b) positive perceptions of managers’ leadership were associated with higher levels of transformational conflict management style and lower levels of hesitant and competitive conflict management styles. Overall, this study indicates that there is a gap between followers’ and managers’ perceptions of leadership and that a more positive evaluation of leadership readiness relates to more positive management styles by the leaders.

The field of biomaterials has advanced towards the molecular and nanoscale design of bioactive systems for tissue engineering, regenerative medicine and drug delivery. Spatial cues are displayed in the 3D extracellular matrix and can include signaling gradients, such as those observed during chemotaxis. Architectures range from the nanometer to the centimeter length scales as exemplified by extracellular matrix fibers, cells and macroscopic shapes. The main focus of this review is the application of a biomimetic approach by the combination of architectural cues, obtained through the application of micro- and nanofabrication techniques, with the ability to sequester and release growth factors and other bioactive agents in a spatiotemporal controlled manner for bone and cartilage engineering.

O artigo propõe uma reflexão sobre os desafios éticos envolvidos na identificação de crianças youtubers no contexto de uma pesquisa científica, evidenciando os impasses e ajustes que surgiram durante a análise dos vídeos. Partimos do entendimento de que a ética em pesquis a é construída contextualmente, em interações concretas e muitas vezes inesperadas e discutimos sobre o equilíbrio entre a proteção e a participação das crianças. A questão ética central — se crianças youtubers, já identificadas publicamente no YouTube, deveriam ter suas imagens e nomes expostos em textos de pesquisa — foi respondida com a decisão de preservar suas identidades. Essa escolha reflete uma abordagem ética que vai além do mero cumprimento formal de normativas, sendo construída a partir de uma vigilância epistemológica com base no diálogo com nossas bases teórico-metodológicas. Ponderamos que os vídeos analisados foram criados para finalidades distintas da proposta da pesquisa e que não tínhamos o consentimento dos responsáveis legais e o assentimento das crianças para serem expostos em uma pesquisa científica. Além das dinâmicas do YouTube, que frequentemente dificultam a mediação parental, a plena compreensão do tratamento de dados online e a possibilidade de haver o oversharing, o que evidencia os desafios éticos que atravessam esse campo de investigação.

[Excerto] Chegaram, sem nenhuma relação causal entre eles, reflexos de luz e sombra provenientes da poesia de Dylan Thomas (1914-1953) e o cinema de Béla Tarr (1955-2026). Tentarei refletir sobre este conceito (a luz e o seu contrário) através das projeções provocadas por duas obras: a antologia Eu vi o tempo assassinar-me (2024), de  Dylan Thomas, e O cavalo de Turim (Tarr, 2011), o último filme do realizador húngaro Béla Tarr, recentemente falecido.