Let $\Omega_n$ be a finite chain with $n$ elements $(n\in\mathbb{N})$, and let $\mathcal{POPI}_{n}$ be the semigroup of all injective orientation-preserving partial transformations of $\Omega_n$. In this paper, for any nonempty subset $Y$ of $\Omega_n$, we consider the subsemigroup $\mathcal{POPI}_{n}(Y)$ of $\mathcal{POPI}_{n}$ of all transformations with range contained in $Y$. We describe the Green's relations and study the regularity of $\mathcal{POPI}_{n}(Y)$. Moreover, we calculate the rank of $\mathcal{POPI}_{n}(Y)$ and determine when two semigroups of this type are isomorphic.

In this paper, we consider the monoids of all partial endomorphisms, of all partial weak endomorphisms, of all injective partial endomorphisms, of all partial strong endomorphisms and of all partial strong weak endomorphisms of a star graph with a finite number of vertices. Our main objective is to exhibit a presentation for each of them.

Technology integration although highly recommended has proved to be complex. This study aims to characterize the perceptions of secondary mathematics teachers (grades 7th to 12th), from Portugal (Braga region) and Brazil (Campinas region), regarding the teaching of Functions and the use of technology. We also intend to consider the context of the two countries, reflecting on justifications for the differences identified (if any). The study adopts a mixed methodology based on a questionnaire applied to 129 Portuguese teachers in Braga region and 136 Brazilian teachers in Campinas region (quantitative dimension) and on an interview to six Portuguese teachers and six Brazilian teachers (qualitative dimension). The results point to similarities between teachers from Portugal and Brazil, but also to some differences. Technology potential is recognized by teacher from both countries, however teachers from Brazil tend to assume a more traditional use of technology, based on showing and more teacher-centered. This difference can be related to the Portuguese curriculum, valuing a relevant use of technology for more than three decades.

Industrial robots are increasingly integrated into manufacturing workspaces, leading to significant changes in work design and altering workers’ framing of work and technology. Even without anthropomorphic design or autonomous features, employees may treat industrial robots as more than mere tools, attributing human-like qualities to them. Yet, prior research typically considers technology either as a tool or as an occasion for altering work relationships between humans, overlooking how relationships with technology itself are crafted. Drawing on 133 interviews across multiple organizations—including robot users, robot producers, and solution providers, we show that mind perceptions (attributions of agency and experience to industrial robots) catalyze relational job crafting with robots. We identify four co-evolving practices—crafting responsibilities, crafting hierarchies, crafting collaboration, and crafting emotional connection—that help workers regain control and regulate daily stress levels, thereby linking relational crafting to both performance and well-being outcomes. Our study extends relational job crafting theory by theorizing mind perceptions as the trigger of human-robot relationality and shifts attention from agentic/anthropomorphic design of technologies to workers’ perceptions of these technologies as core drivers of human-robot-interaction and technology adoption in organizations.

In densely built urban areas, explosive events produce blast waves that interact strongly with surrounding structures, resulting in amplified pressures and highly variable injury patterns. These complex interactions challenge conventional blast models and emphasize the need for improved, rapid injury estimation methods to support effective emergency response and mitigation. To address this need, the present study develops predictive equations for the rapid estimation of TNT blast-induced human injuries in urban environments, with particular emphasis on densely built areas characterized by complex street geometries. These equations were derived through regression analysis of an extensive dataset of simulated blast events with varying charge sizes, placed in three representative urban scenarios characterized by distinct street layouts and topographic conditions. The numerical simulations were performed using validated finite-volume Computational Fluid Dynamics models implemented in the GPU-accelerated commercial software Viper::Blast. The proposed equations allow the delineation of primary and secondary injury zones. Primary injuries are associated with overpressure effects on air-filled organs, while secondary injuries result from debris and projectiles and are directly correlated with predicted damage to masonry elements and glazing. Tertiary and quaternary injuries, which are respectively related to body displacement and impact, burns, inhalation hazards, and psychological effects, are not addressed in the present research. Results show that the urban fabric strongly influences both the extent and the shape of the injury zones. In contrast, terrain topography, provided that slopes remain relatively moderate, has only a minimal effect. Overall, the predictive equations offer a rapid yet reliable tool for quantifying blast-related injuries in urban environments. They support risk assessment, mitigation planning, and emergency response strategies for both accidental and deliberate explosions.

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Dyrosauridae are one of the few clades of large marine vertebrates that survived the Cretaceous/Palaeogene (K–Pg) extinction event. The early diversification of this clade, dated to the Cretaceous, is still poorly understood. We describe a new specimen of Dyrosauridae from the Late Cretaceous of Bentiaba, Angola, represented by a posterior portion of the skull, a left ectopterygoid fragment, and a tooth. Comparative morphological analysis reveals a unique combination of characters distinguishing it from known dyrosaurid taxa but due to the fragmentary nature of the specimen and the absence of key diagnostic features, we assign it to Hyposaurinae indet.. Phylogenetic relationships were tested through maximum parsimony and Bayesian inference, using the SFBD model with time-binning criteria for the K–Pg boundary. Both of our phylogenetic analyses recover this new specimen as Hyposaurinae, which is consistent with our comparative study. Evolutionary rates accelerated during the latest stages of the Cretaceous, although the fossil bias prevents the ability to appreciate their impact on cladogenetic events. We estimated diversification, fossilization, and extinction rates, and we did not find evidence of radiation after the K–Pg in this clade. Biogeographically, this discovery supports hypotheses of longirostrine crocodyliform dispersal in Africa leading to hyposaurine diversification during the Maastrichtian.

In this paper we address a wireless network design problem on a railway line. Given a finite set of locations along a railway line and different types of communication antennas that can be installed at each of these locations, which locations and which type of antenna should be selected to ensure a certain level of signal coverage along the railway line while minimizing construction costs? We formulate the problem as a 0/1 linear optimization model, prove that the problem is NP-hard, and report computational experiments using real and simulated data. The computational tests showed that the model is capable of solving the problem for railway lines longer than any existing real railway lines.

Polysaccharides in plant cell walls serve as a rich carbon and energy source, yet their structural complexity presents a barrier to efficient degradation. To address this, anaerobic microorganisms like R. flavefaciens have developed sophisticated multi-enzyme complexes known as cellulosomes, which enable the efficient breakdown of these recalcitrant polysaccharides. These complexes are assembled through high-affinity interactions between cohesin (Coh) modules in scaffoldin proteins and dockerin (Doc) modules in cellulosomal enzymes. R. flavefaciens FD-1 harbors one of the most intricate cellulosomes described to date, comprising over 200 Doc-containing proteins encoded in its genome. Despite substantial research on this cellulosome, the role of a group of truncated but functional dockerins, known as group-2 Docs, remains unclear. In this study, we present a detailed structural and binding analysis of a Coh-Doc complex involving the cohesin from the cell-anchoring scaffoldin ScaE and a group-2 Doc that bears only one of the two Ca+2-coordinating loops that characterise the canonical Docs. Our findings reveal a novel tripartite binding mechanism, in which the cohesin can simultaneously bind two distinct dockerin units in three alternative conformations. This discovery provides new insights into the modular versatility of the R. flavefaciens cellulosome and sheds light on the mechanisms that enhance its efficiency in polysaccharide degradation.

High-dimensional omics data often contain more variables than observations, which can lead to overfitting and negatively impact the results of classical data analysis methods. To address the issue, supervised variable selection methods are often used, incorporating penalty terms into the model. While effective for selecting task-specific variables, this approach may not preserve the overall dataset structure for multiple downstream analyses. This study aims to evaluate unsupervised variable selection approaches and introduce a novel tool that improves data interpretability while maintaining biological information.

The pursuit of strategies that minimize the number of individuals needing vaccination to control an outbreak is a well-established area in mathematical epidemiology. However, for certain diseases, public policy tends to prioritize immunizing vulnerable individuals over epidemic control. As a result, optimal vaccination strategies may not always be effective in supporting real-world public policies. A similar situation happens when a new vaccine is introduced and is in short supply, as target priority groups for vaccination have to be defined. In this work, we focus on a disease that results in long-term immunity and spreads through a heterogeneous population, represented by a contact network. We study four well-known group centrality measures and show that the GED-Walk offers a reliable means of estimating the impact of vaccinating specific groups of individuals, even in suboptimal cases. Additionally, we depart from the search for target individuals to be vaccinated and provide proxies for identifying optimal groups. While the GED-Walk is the most useful centrality measure for suboptimal cases, the betweenness (a related, but different centrality measure) stands out when looking for optimal groups. This indicates that optimal vaccination is not concerned with breaking the largest number of transmission routes, but interrupting geodesic ones.

The European Metal sector is at a critical juncture, navigating through the complex landscape of the twin transition towards digitalization and sustainability. This transformative journey, though essential, is fraught with challenges that if not addressed, could undermine the sector's resilience, competitiveness and social equity. The Metallica project emerges as a pivotal initiative in this context, aiming to mitigate these challenges by fostering enhanced worker engagement, participation and conflict resolution.

The European Metal sector is at a critical juncture, navigating through the complex landscape of the twin transition towards digitalization and sustainability. This transformative journey, though essential, is fraught with challenges that if not addressed, could undermine the sector's resilience, competitiveness and social equity. The Metallica project emerges as a pivotal initiative in this context, aiming to mitigate these challenges by fostering enhanced worker engagement, participation and conflict resolution.

Although the Portuguese industry is often considered semi-peripheral within the European context. This classification stems from Portugal's position in the global and European economic systems. However, the Portuguese automotive industry is a significant sector within the European automotive landscape. Portugal’s industrial sector is heavily integrated into European supply chains, particularly in industries like automotive, textiles, and electronics. However, it often relies on core European countries (e.g., Germany, France) for advanced technology, capital, and market access. This is also the case for the Portuguese automotive.

The potential of STE(A)M has been widely recognised in recent years; however, challenges have also been identified in the implementation of this approach, making it important to deepen research into teachers’ practices. In this study, we conducted a systematic review focused on teaching practices within a STE(A)M approach, to understand what challenges and limitations teachers encounter, as well as the possibilities authors suggest to overcome them. The research question is: What are the challenges and potentialities of implementing the STE(A)M approach in teachers’ practices? This review analysed articles indexed in the Web of Science and Scopus databases over the last eight years, following the PRISMA scheme. The 26 articles examined highlight challenges such as time management, lack of resources and funding, limited guidance, gaps in teacher training, difficulty integrating subject areas, issues implementing new technologies and obstacles imposed by school structures. In light of these, the following proposals were suggested: placing greater emphasis on STE(A)M in initial and continuing teacher education, increasing support from schools and government bodies, encouraging collaborative work between teachers from different areas, adopting innovative strategies and methodologies and offering a clearer conceptualisation of STE(A)M.