REPOSITÓRIO P.PORTO
Repositório Científico do Politécnico do Porto
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Insights on designing a novel 99% biodegradable FFP2 BioMask through interdisciplinary applied research
Publication . Chakraborty, Shujoy; Loyens, Dirk; Aston, Jeremy; Jain, Harshit; Ornelas, Marta; Gouveia, Rosa de
Objective: This research developed an environmentally sustainable alternative, called BioMask, to non-biodegradable polypropylene FFP2 masks, addressing the dual challenge of medical waste reduction and public health protection through interdisciplinary collaboration. Approach: The study employed Research through Design (RtD) methodology integrating expertise from design, nanomaterial science, fibre engineering, and medicine within a 15-month applied research project. RtD facilitated concurrent product-process development by using iterative prototyping as a common language across disciplines, enabling real-time problem-solving rather than traditional sequential development. The interdisciplinary consortium developed a novel sandwich material consisting of an electrospun cellulose acetate nanofibre filtration layer combined with viscose and banana fabric substrates, utilising design thinking to bridge technical knowhow across the disciplines mentioned. Results: The BioMask achieved key performance metrics that surpass conventional alternatives: 1. Filtration efficiency: 98.3% for 0.3-micron particles (vs. 65-94% for standard FFP2 masks) 2. Biodegradability: 100% decomposition in 83 days (vs. 0% for polypropylene masks) 3. Material composition: 99% biodegrahen possibledable components 4. Technology readiness: Achieved Technology Readiness Level 4 (TRL) validated with a provisional Portuguese patent protection. Interdisciplinarity: The collaborative approach revealed disciplinary synergies: nanomaterial scientists provided the core filtration technology, designers identified user-centred concerns and optimised morphology, fibre engineers ensured manufacturing feasibility, and medical professionals validated clinical applicability. Insights: This interdisciplinary process model provides transferable insights and a replicable structure for addressing complex sustainability challenges in medical product development. The approach demonstrates design thinking serving as a bridge between disciplines, translating laboratory innovations into commercially viable, environmentally responsible solutions. Broader impact: The output demonstrated a proof-of-concept utilizing nano material manufacturing with electrospinning and machine stitching the BioMask sandwich material achieving 25 functional prototypes, integrating banana fabric, cellulose acetate, and viscose. Future commercialization depends on scaling up manufacturing and achieving EN149 / FFP2 certification.
A Genetic Approach for Dynamic Job-Shop Scheduling Problems
Publication . Madureira, Ana Maria; Ramos, Carlos; Silva, Sílvio do Carmo
[Introduction] Since Davis [4] proposed the first Genetic Algorithm(GA) to address scheduling problems in 1985, GAs
have been widely used in manufacturing scheduling applications. However, most of the works deal with
optimisation of the scheduling problem in static environments, whereas many real world problems are
dynamic, frequently subject. to several sorts of random occurrences and perturbations, such as random
job releases, machine breakdowns, jobs cancellation and due date and time processing changes.
Due to their dynamic nature, real scheduling problems have an additional complexity in relation
to static ones. In many situations these problems, even for apparently simple situations, are hard to
solve, i.e. the time required to compute an optimal solution increases exponentially with the size of the
problem [1]. GAs have been extensively used in the context of Job-Shop Scheduling Problems (JSSP).
If all jobs are known before processing starts the JSSP is called static, while if job release times are not
fixed at a single point in time, ie. jobs arrive to the system at different times, the problem is called
dynamic. Scheduling problems can also be classified as deterministic, when processing times and all
other parameters are known and fixed, and stochastic, when some or all parameters are uncertain [7].
The proposed approach deals with these two cases of dynamic scheduling: deterministic and stochastic.
For such class of problems, the goal is no longer to find a single optimum, but rather to continuously
adapt the solution to the changing environment. The purpose of this paper is to describe an approach
based on GA for solving dynamic scheduling problems, where the products (jobs) to be processed have
due dates. This paper starts by presenting a scheduling system, based on Genetic Algorithms for the
resolution of the dynamic version of Single Machine Scheduling Problem (SMSP). The approach used
adapts the resolution of the static problem to the dynamic one in which changes may occur continually.
This takes into account dynamic occurrences in a system and adapts the current population to a new
regenerated population. Then, it is proposed an approach for the resolution of the Job-Shop Scheduling
Problem (JSSP) in dynamic environments.
The paper is structured as follows: section 2 provides a description of the considered scheduling problem. Section 3 summarises an approach for the resolution of the Dynamic Single Machine Scheduling
Problem. The proposed approach for dynamic scheduling is presented in section 4. Finally, the paper concludes with a summary and some ideas for future work.
A Parallel Architecture for Solving Constraint Satisfaction Problems
Publication . Mendes, Rui; Pereira, Jorge R.; Neves, José
[Introduction] Real world problems can often be described by a set of constraints to be satisfied, where the goal is to
find a feasible solution for the problem. The use of constraints allows one to model a wide variety of problems in a straightforward manner. However, finding a solution that either satisfies all constraints or maximizes some benefit is usually difficult, as existing algorithms for both problems are NP-hard.
Furthermore, it is not always possible to satisfy all the constraints. In such cases, the goal is to find a solution that satisfies the maximum number of constraints (MMAX-CSPs) or one that satisfies the most important ones (MAX-WCSPs, where each constraint has a weight). Currently, local search is widely used to tackle these difficult problems. However, those methods are usually incomplete (i.e., they do not guarantee the optimum), and are often mislead by local optima.
This situation is usually handled by restarting the search from another starting point. It is our goal in this paper to present a parallel architecture for solving constraint satisfaction problems (AntCSP); i.e., a parallel architecture that combines the stigmergetic capabilities of Ant Colony Optimization (ACO) metaheuristics, with local search heuristics to solve MANX-CSPs and Constraint Satisfaction and Optimization Problems (CSOPs).
One of the main advantages of this approach is that no auxiliary structure is needed. The structure followed by the ants is the proof tree itself, in which the pheromones are laid. This not. only provides a very efficient implementation of pheromone updating but also a more general approach to solve CSPs. The other advantage is the use of parallelism both to have a number of ant colonies running in parallel and to have function distribution of local search procedures. This architecture thus provides a powerful tool to tackle these difficult problems by using available processing power.
Segurança e saúde em laboratórios académicos: conhecimentos, atitudes e práticas de estudantes do Ensino Superior
Publication . Ribeiro, Inês; Carvalhais, Carlos; Alberto Alves Carvalhais, Carlos
As instituições de ensino superior, particularmente aquelas que dispõem de laboratórios de ensino e investigação nas suas infraestruturas, desempenham um papel importante na transmissão de conhecimentos e atitudes sobre segurança química aos seus estudantes (Walters et al., 2017). O presente estudo tem como objetivo avaliar o conhecimento e as atitudes dos estudantes do ensino superior de diferentes cursos relativamente à segurança química em laboratório. Foi realizado um estudo transversal, recorrendo a um questionário adaptado e traduzido para português (Al-Zyoud et al., 2019). O instrumento incluiu um total de vinte e sete questões e foi aplicado a estudantes inscritos em cursos de licenciatura e pós-graduação que integram práticas laboratoriais nos seus planos curriculares, entre março e julho de 2025. Participaram no estudo 284 estudantes, provenientes dos diferentes ciclos de ensino superior politécnico e universitário nas áreas das ciências da vida e da saúde (CTeSP = 4,2%; Licenciatura = 70,4%; Mestrado = 21%; Doutoramento = 4,2%). Os resultados evidenciaram que, apesar de uma elevada proporção de estudantes demonstrar um bom nível de conhecimento sobre pictogramas de perigo — sendo o pictograma comburente o menos reconhecido (55% de respostas corretas) e o tóxico o mais conhecido (99% de respostas corretas) — as atitudes relatadas nem sempre são as mais adequadas. Cerca de 20% dos participantes referiram que os equipamentos de proteção individual são obrigatórios apenas quando se manuseiam produtos químicos, e 34,5% afirmaram nunca ter consultado as fichas de dados de segurança dos produtos utilizados, o que pode comprometer a sua própria segurança e a de terceiros. Não foram encontradas diferenças estatisticamente significativas entre os diferentes níveis de ensino relativamente ao conhecimento sobre a temática. Os resultados obtidos evidenciam a necessidade de ajustes curriculares. A exposição precoce a conceitos de segurança química e laboratorial tem o potencial de promover o desenvolvimento de estudantes e futuros profissionais mais conscientes. A integração de módulos de segurança nos planos de estudo poderá aumentar o conhecimento e as competências necessárias para tomar decisões informadas que contribuam para a redução de acidentes e incidentes em ambiente laboratorial.
Scapular clinical assessment and therapeutic exercises for chronic shoulder pain: a narrative review
Publication . Melo, Ana S. C.; Félix, José; Cruz, Eduardo B.; Vilas-Boas, J. Paulo; Sousa, Andreia S. P.; Pinheiro de Sousa, Andreia Sofia; Sousa Félix, José Manuel
Previous studies have reported that a significant proportion of the general population will experience shoulder pain at some point of their lifetime [1], which could lead to disability [2]. Particularly, cases that evolve into chronic shoulder pain can further compromise shoulder function. Among the different joints of shoulder complex that could be involved in these conditions, the scapulothoracic joint, possibly due to its major role in the shoulder function and upper limbs’ activities [3], is commonly associated with changes in scapular kinematics and related muscular activity [4, 5]. These findings, related to the chronicity of shoulder pain and to motor control adaptations, along with epidemiological data on this common musculoskeletal condition [1], justify the continued search for more effective rehabilitation approaches.