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- The Adaptation of Land Forces to the New Multipolar OrderPublication . Vieira, Ricardo José SimõesThe adaptation of land forces to the new multipolar order is essential for understanding the current dynamics of the International System. This essay analyses the relationship between shifts in global polarity and the reorganisation of land forces, investigating whether strategic competition is driving a return to a conventional era. The research findings indicate that the unipolar era favoured disarmament policies, whereas multipolarity has intensified geopolitical tensions, making military power a central element of state security. The rise of revisionist powers, such as Russia and China, has reinforced the need for conventional rearmament. The 2022 invasion of Ukraine exemplifies this transition, highlighting the renewed relevance of land forces and conventional logistics. A mechanised, division-level military structure has replaced the expeditionary model of the unipolar era. It is concluded that multipolarity drives conventional militarisation, although other factors may also influence this trend.
- Assessment of Airport Pavement Condition Index (PCI) Using Machine LearningPublication . Santos, Bertha; Studart, André; Almeida, Pedro G.Pavement condition assessment is a fundamental aspect of airport pavement management systems (APMS) for ensuring safe and efficient airport operations. However, conventional methods, which rely on extensive on-site inspections and complex calculations, are often time-consuming and resource-intensive. In response, Industry 4.0 has introduced machine learning (ML) as a powerful tool to streamline these processes. This study explores five ML algorithms (Linear Regression (LR), Decision Tree (DT), Random Forest (RF), Artificial Neural Network (ANN), and Support Vector Machine (SVM)) for predicting the Pavement Condition Index (PCI). Using basic alphanumeric distress data from three international airports, this study predicts both numerical PCI values (on a 0–100 scale) and categorical PCI values (3 and 7 condition classes). To address data imbalance, random oversampling (SMOTE—Synthetic Minority Oversampling Technique) and undersampling (RUS) were used. This study fills a critical knowledge gap by identifying the most effective algorithms for both numerical and categorical PCI determination, with a particular focus on validating class-based predictions using relatively small data samples. The results demonstrate that ML algorithms, particularly Random Forest, are highly effective at predicting both the numerical and the three-class PCI for the original database. However, accurate prediction of the seven-class PCI required the application of oversampling techniques, indicating that a larger, more balanced database is necessary for this detailed classification. Using 10-fold cross-validation, the successful models achieved excellent performance, yielding Kappa statistics between 0.88 and 0.93, an error rate of less than 7.17%, and an area under the ROC curve greater than 0.93. The approach not only significantly reduces the complexity and time required for PCI calculation, but it also makes the technology accessible, enabling resource-limited airports and smaller management entities to adopt advanced pavement management practices.
- Automated Geographic Information System Multi-Criteria Decision Tool to Assess Urban Road Suitability for ActiveMobilityPublication . Santos, Bertha; Ferreira, Sandro Alfaro ; Lucena, Pollyana;The planning of greener, more accessible, and safer cities is the focus of several strategies that aim to improve the population’s quality of life. This concern for the environment and the population’s quality of life has led to the implementation of active mobility policies. The effectiveness of the mobility solutions that are sought heavily depends on the identification of the main factors that favor their use, as well as how adequate urban spaces are in minimizing existing difficulties. This study presents an automated geographic information system (GIS) decision support tool that allows the identification of the level of suitability of urban transportation networks for the use of active modes. The tool is based on the determination of a set of mobility indices: walkability, bikeability, e-bikeability, and active mobility (a combination of walking and cycling suitability). The indices are obtained through a spatial multi-criteria analysis that considers the geometric features of roads, population density, and the location and attractiveness of the city’s main trip-generation points. The treatment, representation, and study of the variables considered in the analysis are carried out with the aid of geoprocessing, using the spatial and network analysis tools available in the GIS. The Model Builder functionality available in ArcGIS® was used to automate the various processes required to calculate walking, cycling, and e-biking travel times, as well as the mobility indices. The developed tool was tested and validated through its application to a case study involving the road network of the urban perimeter of the medium-sized city of Covilhã, Portugal. However, the tool is designed to be applied with minimal adaptation to different scenarios and levels of known input information, providing average or typical values when specific information is not available. As a result, a flexible and automated GIS-based tool was obtained to support urban space and mobility managers in the implementation of efficient measures compatible with each city’s scenario.
- Beeswax-enriched tricalcium phosphate/hydroxyapatite/sodium alginate/ thymol 3D-printed scaffolds for application in bone tissue engineeringPublication . Francisco, Martinho Jorge ; Cabral, Cátia Solange Duarte; Calvinho, Paula Cristina Nunes Ferreira ; Correia, Ilídio Joaquim Sobreira ; Moreira, André FerreiraTissue engineering, particularly bone tissue engineering (BTE), continues to pose significant challenges to modern medicine. In this work, a rapid prototyping technique was explored to create 3D scaffolds using a Fab@Home 3D-Plotter extruder. For that purpose, a novel composite mixture containing tricalcium phosphate (TCP), hydroxyapatite (HAp), sodium alginate (SA), beeswax (BW), and thymol (TM) was formulated. BW and TM resulted in 3D scaffolds with rougher surfaces and moderate hydrophilic profiles, properties crucial for mediating cell adhesion and proliferation. Moreover, the 3D scaffolds containing BW displayed a significant increase in compressive strength and Young modulus, being comparable to those exhibited by trabecular bone. TM loading prevented the establishment of Staphylococcus aureus and Escherichia coli infections, inhibiting bacterial adhesion and proliferation at the scaffolds' surface. Additionally, the cytocompatibility of the scaffolds was confirmed over 21 days, with the adhesion and proliferation of Human osteoblasts (hOB) at the scaffold's surfaces. Simultaneously, calcium and phosphate ions accumulated at the scaffolds' surface, forming apatite crystals. Therefore, this improved composite mixture showed promising results for being applied in BTE, not only facilitating hOB cell adhesion and proliferation but also avoiding bacterial infection, addressing a critical challenge in implant-based therapies.
- Dual-crosslinked injectable in situ forming Alginate/CaCl2/Pluronic F127/ α-Cyclodextrin hydrogels incorporating Doxorubicin and graphene-based nanomaterials for cancer chemo-photothermal therapyPublication . Gonçalves, Joaquim; Melo, Bruna Daniela Lopes ; Pouso, Manuel António do Rosário ; Correia, Ilídio Joaquim Sobreira ; de Melo-Diogo, DuarteInjectable in situ forming hydrogels have been emerging due to their capacity to perform the direct delivery of therapeutics into the tumor site with minimal off-target leakage. Particularly, physical crosslinked injectable in situ forming hydrogels are appealing due to their straightforward preparation that exploits the native jointing capabilities of specific polymers/materials. However, the features of these hydrogels (e.g., injectability, degradation, swelling) are strongly pre-determined by the physical interactions available on the selected polymers/ materials, occasionally yielding undesired outcomes. Thus, the combination of multiple physical crosslinking cues may allow the preparation of hydrogels with enhanced properties. In this work, a dual-crosslinked injectable in situ forming hydrogel was engineered by combining Pluronic F127/α-Cyclodextrin and Alginate/CaCl2 (i.e., combination of host-guest and electrostatic interactions), being loaded with Doxorubicin (chemotherapeutic drug) and Dopamine-reduced Graphene Oxide (photothermal nano-agent) for application in cancer chemophotothermal therapy. When compared to the single-crosslinked hydrogels, the dual-crosslinking contributed to the assembly of formulations with suitable injectability and improved degradation and water absorption behaviors. Moreover, the dual-crosslinked hydrogels presented a good photothermal capacity (ΔT ≈ 14 ◦C), leading to a 1.18-times enhanced Doxorubicin release. In in vitro cell-based studies, the dual-crosslinked hydrogels exhibited an excellent cytocompatibility towards healthy (normal human dermal fibroblasts) and breast cancer (MCF-7) cells. As importantly, the dual-crosslinked hydrogels were able to mediate a chemophotothermal effect that diminished the cancer cells’ viability to just 23 %. Overall, the developed dualcrosslinked injectable in situ forming hydrogels incorporating Doxorubicin and Dopamine-reduced Graphene Oxide are a promising macroscale system for breast cancer chemo-photothermal therapy.
- O meu coração diz-me…: Antígona num filme de Sophie DeraspePublication . Mancelos, João de; Morais, Carlos; Ferreira, António Manuel; Coimbra, Rosa Lídia; Brasete, FernandaNo filme Antigone (2019), a guionista e realizadora canadiana Sophie Deraspe subverte a peça de teatro homónima (411 a.C.) de Sófocles. Nesta comunicação, pretendo examinar os mecanismos utilizados para conseguir esta adaptação tão radical quanto imaginativa. Para tanto, comparo os dois textos relativamente às quatro categorias narrativas: espaço, tempo, personagens e enredo. Para escorar o meu estudo, recorro à nota de intenções da realizadora e a ensaios de vários críticos de teatro e cinema.
- Renewable Photo-Cross-Linkable Polyester-Based Biomaterials: Synthesis, Characterization, and Cytocompatibility AssessmentPublication . Cernadas, Maria Teresa; Pereira, João; Melo, Bruna Daniela Lopes ; de Melo-Diogo, Duarte; Correia, Ilídio Joaquim Sobreira ; Alves, Patrícia; Calvinho, Paula Cristina Nunes FerreiraTThe present work consist of the synthesis of photo-crosslinkable materials, based on unsaturated polyesters (UPs), synthesized from biobased monomers from renewable sources such as itaconic acid and 1,4- butanediol. The UPs were characterized to assess the influence of polycondensation reaction temperature and cross-linking time on their final properties. For this purpose, different UV irradiation exposure periods were tested. Homogeneous, uniform, and transparent films were obtained after 1, 3, and 5 min of UV exposure. These cross-linked films were then characterized. All materials presented high gel content, which was dependent on the reaction’s temperature. The thermal behaviors of the UPs were shown to be similar. In vitro hydrolytic degradation tests showed that the materials can undergo degradation in phosphate-buffered saline (PBS) at pH 7.4 and 37 °C, ensuring their biodegradability over time. Finally, to assess the applicability of the polyesters as biomaterials, their cytocompatibility was determined by using human dermal fibroblasts.
- Statistical analysis of an in-vehicle image-based data collection method for assessing airport pavement conditionPublication . Feitosa, Ianca Teixeira ; Santos, Bertha; Gama, Jorge; Almeida, Pedro G.This study presents a comprehensive comparative statistical analysis to validate a novel in-vehicle image-based method for collecting pavement condition data in airport environments. It highlights the method’s potential to address key challenges faced by airport pavement managers, such as the need for continuous maintenance and the demand for fast, effective, and reliable inspection procedures. The in-vehicle system integrates laser scanning systems, image capture, and georeferencing devices to collect pavement distress data, and its accuracy and reliability are evaluated statistically. The primary objective is to validate and enhance this novel inspection approach, which shows strong potential as an effective alternative for comprehensive pavement evaluation, enabling continuous, rapid monitoring and the analysis of trends. Validation was performed by means of a detailed statistical comparison of pavement distress density on the main runway of Amílcar Cabral International Airport, Sal Island, Cape Verde, based on data collected using the proposed in-vehicle and the traditional on-foot inspection methods. Non-parametric repeated measures analysis (nparLD) showed statistically similar results between methods for 9 of 12 distress type-severity combinations (4 types × 3 levels), especially for medium and high severity cases, and that pavement section and method-section factors were significant in 10 and 9 of 12 cases, respectively, indicating spatial variability. Kruskal-Wallis tests were applied to each method separately. Significant section-based differences were found in 11 of 12 cases for the traditional method and in 2 of 12 cases for the in-vehicle image-based method, indicating greater sensitivity of the on-foot inspection to spatial variation in distress distribution. These findings support the statistical validation of the proposed method for practical application in airport pavement management. Furthermore, the comprehensive analysis, which included correlation and autocorrelation studies, revealed a bias in severity level assignment during traditional on-foot inspections. The findings highlight time-efficiency gains with the image-based method and suggest improvements, such as enhancing image quality and providing inspector training to increase the accuracy of severity level classification. These results offer valuable insights for airport pavement managers, contributing to improved safety, operational efficiency, and resilience in the face of growing air traffic demands.
- Traffic Scheduling and Resource Allocation for Heterogeneous Services in 5G New Radio Networks: A Scoping ReviewPublication . Pindi, Ntunitangua René; Velez, Fernando J.The rapid evolution of 5G New Radio networks has introduced a wide range of services with diverse requirements, complicating their coexistence within the shared radio spectrum and posing challenges in traffic scheduling and resource allocation. This study aims to analyze and categorize the methods, approaches, and techniques proposed to ensure efficient joint and dynamic packet scheduling and resource allocation among heterogeneous services—namely eMBB, URLLC, and mMTC—in 5G and beyond, with a focus on Quality of Service and user satisfaction. This scoping review draws from publications indexed in IEEE Xplore and Scopus and synthesizes the most relevant evidence related to packet scheduling across heterogeneous services, highlighting key approaches, core performance metrics, and emerging trends. Following the PRISMA-ScR methodology, 48 out of an initial 140 articles were included for explicitly addressing coexistence, scheduling, and resource allocation. The findings reveal a research emphasis on eMBB and URLLC coexistence, while integration with mMTC remains underexplored. Moreover, the evidence suggests that hybrid and deep learning-based approaches are particularly promising for tackling coexistence and resource management challenges in future mobile networks.