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The Acute Effect of Methylphenidate Ingestion in a Visuomotor Task at Absolute Power Alpha in Healthy Subjects
(2026-02-01) Lourenço, Vinicius; Amoroso, Carlos; Vicente, Renan; Azevedo, André; Nicoliche, Eduardo; Velasques, Bruna; Nobre, Marcelo; Cagy, Mauricio; Ribeiro, Pedro; Budde, Henning; Vasconcelos, Alex; Fonseca, Renato; Zanchetta, Giovanna; Orsini, Marco; MacHado, Marcos; Barreto, Sávio; Teixeira, Silmar; Bastos, Victor Hugo; Marinho, Francisco Victor; Fernandes, Isabelle; Nardi, Egídio
Background Methylphenidate (MPH) is a psychostimulant widely used to enhance attention and executive functions through increased dopaminergic and noradrenergic transmission. Although its effects on cognitive performance are well documented, its acute influence on cortical oscillatory activity, particularly α power, during tasks requiring simultaneous motor and cognitive processing remains poorly understood in healthy adults. Objective To investigate the acute effects of 10 mg MPH on absolute α power (8-12 Hz) in frontal regions during a visuomotor task in healthy subjects. Methods A total of 13 right-handed healthy adults (7 men; age 25.6 ± 4.5 years) participated in a randomized, double-blind, placebo-controlled, crossover study. A 20-channel electroencephalography (EEG) was recorded before and after execution of the MIRA visuomotor task (joystick response when a moving target crosses a previously memorized position) under placebo and MPH (10 mg) conditions, with sessions 1 week apart. Absolute α power was compared using two-way ANOVA (condition vs. moment: pre- vs. post-joystick press), followed by paired t -tests when appropriate. Results Significant condition versus moment interactions were observed at F3 (p = 0.006), F4 (p = 0.003), and F8 (p = 0.023). The main effects of condition and/or moment occurred at Fp1, Fp2, and Fz (all p < 0.05). The use of MPH attenuated or reversed the typical task-related α desynchronization seen under placebo, especially in right frontal regions. Conclusion A single 10 mg dose of MPH homogeneously modulates frontal α power during a visuomotor task, promoting sustained cortical activation. This paradigm emerges as a sensitive tool for studying motor-cognitive coupling and may contribute to understanding MPH mechanisms in both healthy and clinical populations.
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Terahertz metamaterial-based perfect absorber biosensor with AI integration and multiband double-negative response for early non-melanoma skin cancer detection
(2026-03-01) Hamza, Musa N.; Alibakhshikenari, Mohammad; Virdee, Bal; Jayanthi, Renu Karthick Rajaguru; Lavadiya, Sunil; Din, Iftikhar ud; Sanches, Bruno; Koziel, Slawomir; Panda, Abinash; Farmani, Ali; Mezache, Zinelabiddine; Shamsan, Zaid Ahmed; Zakeri, Hassan; Hung, Tran Huy; Department of Engineering
This paper presents a multiband terahertz metamaterial-based biosensor designed as a perfect absorber for the early detection of non-melanoma skin cancer. The proposed structure integrates a meticulously engineered multilayer architecture that achieves simultaneous negative permittivity, permeability, and refractive index (double-negative response) within the 0–5 THz range. Unlike conventional terahertz sensors that rely on one or two resonances, our design produces approximately twenty high-Q absorption peaks, with eleven exceeding 95%, four exceeding 97%, and two surpassing 99% absorption. These dense resonances enhance field localization and increase sensitivity to dielectric variations in biological tissue. Numerical simulation demonstrates a sensitivity of 629.95 THz/RIU and a figure of merit of 15,179.59 RIU−1, significantly outperforming existing metamaterial biosensors. To further improve diagnostic capability, a broadband spectral-analysis framework is incorporated to analyze the full terahertz spectral response using Euclidean distance, mean squared error, and correlation metrics. The Spectral classification framework reliably distinguishes between healthy and cancerous tissue profiles, enabling an automated and robust detection. The biosensor's performance is further validated by incorporating it into a microwave imaging system, which provides spatial confirmation of cancerous tissue. These results establish the proposed device as a compact, high-resolution, and non-invasive platform for the early diagnosis of non-melanoma skin cancer.
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Success Conditions for Sustainable Geothermal Power Development in East Africa : Lessons Learned
(2026-02) Ingason, Helgi Thor; Fridgeirsson, Thordur Vikingur; Department of Engineering
Geothermal energy is a crucial component of climate adaptation and sustainability transitions, as it provides a dependable, low-carbon source of baseload power that can accelerate sustainable energy transitions and enhance climate resilience. Yet, in East Africa—one of the world’s most promising geothermal regions, with the East African Rift—a unique climate-energy opportunity zone—the harnessing of geothermal power remains slow and uneven. This study examines the contextual conditions that facilitate the successful and sustainable development of geothermal power in the region. Drawing on semi-structured interviews with 17 experienced professionals who have worked extensively on geothermal projects across East Africa, the analysis identifies how technical, institutional, managerial, and relational circumstances interact to shape outcomes. The findings indicate an interdependent configuration of success conditions, with structural, institutional, managerial, and meta-conditions jointly influencing project trajectories rather than operating in isolation. The most frequently emphasised enablers were resource confirmation and technical design, leadership and team competence, long-term stakeholder commitment, professional project management and control, and collaboration across institutions and communities. A co-occurrence analysis reinforces these insights by showing strong patterns of overlap between core domains—particularly between structural and managerial factors and between managerial and meta-conditions, highlighting the mediating role of managerial capability in translating contextual conditions into operational performance. Together, these interrelated circumstances form a system in which structural and institutional foundations create the enabling context, managerial capabilities operationalise this context under uncertainty, and meta-conditions sustain cooperation, learning, and adaptation over time. The study contributes to sustainability research by providing a context-sensitive interpretation of how project success conditions manifest in geothermal development under climate transition pressures, and it offers practical guidance for policymakers and partners working to advance SDG 7 (Affordable and Clean Energy), SDG 9 (Industry, Innovation and Infrastructure), and SDG 13 (Climate Action) in Africa.
Verk
A Multi-Criteria Framework for Sustainable Structural Design Tools in Early-Stage Design
(2026-09-03) Hamdallah, Mohammed; Nasser Asad, Sarah; Heinonen, Jukka Taneli; Faculty of Civil and Environmental Engineering
The construction industry’s digital maturity remains critically low in early-stage structural design, the phase where decisions most significantly dictate a building's total lifecycle impact. While a plethora of digital tools claim to facilitate sustainability, practitioners lack a systematic, evidence-based framework for tool selection, often leading to sub-optimal workflows and a "tool-choice paradox." This study addresses this gap by presenting a qualitative evaluation of three prominent tools representing distinct digital paradigms: Carbon Designer 3D (cloud-based schematic estimation), Structural PANDA (generative optimization), and Carbo-Life Calculator (BIM-integrated evaluation). Using the Analytic Hierarchy Process (AHP), these tools are assessed against three core pillars: efficiency, decision support, and user experience, decomposed into 11 specific functional criteria. To ground the model, performance scoring was derived from a real-world office building case study. Our findings reveal a critical trade-off between automation and accessibility: Structural PANDA demonstrates superior generative design integration but requires high computational literacy, whereas Carbon Designer 3D excels in rapid estimation but lacks geometric flexibility. Meanwhile, Carbo-Life Calculator provides robust BIM integration for carbon tracking but fails to offer the comparative trade-off capabilities essential for iterative design. By isolating these qualitative performance drivers, this article contributes a streamlined selection matrix and a decision-support framework. This enables engineering firms and researchers to align tool selection with specific project requirements and institutional technical capacity, ultimately fostering a more effective transition toward low-carbon structural design.
Verk
Exploring the Viability of Utilizing Slag Waste in Concrete through LCA: A Case Study in Giessen, Germany
(fib. The International Federation for Structural Concrete, 2026-09-03) Hamdallah, Mohammed; Cunha, Jaime; Qazi, Sonaila; Górecki, Jarosław; Faculty of Civil and Environmental Engineering
According to statistics from the VDI Centre for Resource Efficiency, approximately 30.1 million tons of cement were utilized for construction purposes in Germany in 2020, resulting in an estimated emission of 28 million tons of CO2. Given that concrete is a key material in almost 30% of residential construction, it is imperative to seek methods to reduce cement and clinker usage. One promising avenue involves integrating waste materials into concrete, offering the dual advantage of lowering cement consumption while effectively managing industrial waste. However, the practicality of this approach heavily relies on the availability and quantity of waste materials. To delve deeper into this concept, a study was conducted in Giessen, Germany, with a focus on managing waste from local steel mills, which produce approximately 0.6 tons of waste per ton of steel. This waste encompasses various materials such as steelmaking slag, electric arc furnace dust, mill slag, and zinc sludge. The study examined four concrete scenarios, each involving different levels of cement substitution with Ground Granulated BlastFurnace Slag (GGBFS). These scenarios included Ultra-High-Performance Concrete (UHPC) with 40% substitution, Conventional Concrete (CC) with 40% and 20% substitution, and CC without waste valorization serving as the control mixture. Evaluations spanning 100 and 200-year lifespans indicated that CC with 40% GGBFS had the least environmental impact over a century. However, over a 200-year period, the durability of UHPC positioned it as the most environmentally friendly option in terms of embodied energy, considering the respective design lifespans of both mixtures. Further analysis, factoring in the reduction in reinforcement within the UHPC mixture, however, it still has the highest environmental for the 100-year design life span (without considering the durability factor).

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