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Drought, grazing routes and resource use by small-ruminant pastoralists in Montesinho, northeastern Portugal
No full textClimate projections for the Mediterranean area indicate a rise in temperature and an increase in drought frequency, which directly impact water availability and consequently, ecosystems. In the protected area of Montesinho in northeast Portugal, sheep and goat pastoralism characterizes the landscape and plays an important socio-economic role. However, like in many regions of the globe, this historical activity is becoming increasingly unsustainable due to shifting climatic conditions. To understand the impact of climate change on water availability in the park and its consequences for small ruminant pastoralism, trends in rainfall and temperature were analyzed using historical climate data from 1951 to 2022, and semi-structured interviews with local shepherds provided insight into their perceptions on this matter. We used TWI and NDVI to map relative moisture and green forage patterns underlying shepherds’ grazing-route decisions. Findings revealed a decrease in precipitation during winter and spring, with a significant increase during autumn months, and local knowledge revealed a focus on drying springs and shifts in seasonal patterns that led to pastoral adaptations like adjusting grazing routes and increasing reliance on alternative water sources. This study concluded that pastoralism in this region faces significant climatic challenges, highlighting the need to implement adaptive strategies to improve the livelihood of these communities and increase their resilience in a fast-changing environment. Large-scale aid and locally addressed actions, such as improving water infrastructures and promoting drought-tolerant vegetation growth, are key to the long-term sustainability of this ancient practice.The author(s) declared that financial support was received for this work and/or its publication. This work was supported by the Foundation for Science and Technology (FCT), under the project MTS/CAC/0028/2020: PASTOpraxis, and by the European Union’s Horizon Europe research and innovation programme (AF4EU, grant agreement No. 101086563)
Optimization approaches in electric machine design: insights from a bibliometric analysis
No full textOptimizing the design of electric machines is a complex task due to the large number of interrelated geometric and physical parameters that influence performance, efficiency, cost, and sustainability. Numerous deterministic and stochastic optimization techniques have been developed to address these challenges, each presenting distinct advantages and limitations. Deterministic approaches, though computationally efficient, often converge to local minima, while stochastic methods provide broader search capabilities at the expense of higher computational effort. Despite the growing application of optimization in electric machine design, a comprehensive bibliometric overview of this research area is lacking. This study aims to fill that gap by conducting a bibliometric analysis of optimization methods applied to electric machine design. Using data retrieved from the Web of Science (WoS) and analyzed through co-citation mapping with VOSviewer, 246 relevant articles were examined, resulting in a focused sample of 73 key studies. The analysis identifies the most frequently optimized machine types, the main optimization objectives, and the predominant methodologies employed in recent years. By addressing these dimensions, this work provides a conceptual reference framework to guide both academic researchers and industry professionals in selecting appropriate optimization strategies. The results also highlight emerging trends and future research opportunities, contributing to a deeper understanding of the evolution and intellectual structure of optimization in electric machine design.This work was supported by FCT - Fundação para a Ciência e Tecnologia, I.P. by projects: CeDRI, UID/05757/2025 (DOI: https://doi.org/10.54499/UID/05757/2025) and UID/PRR/05757/2025 (DOI: https://doi.org/10.54499/UID/PRR/05757/2025); SusTEC, LA/P/0007/2020 (DOI: https://doi.org/10.54499/LA/P/0007/2020)
Molecular insights into spined loaches (Cobitidae: Cobitis) reveal the complex evolutionary history of freshwater fishes in the Iberian Peninsula and North Africa
No full textPalaeogeographic and tectonic rearrangements of rivers have significantly influenced the phylogeography of Iberian and North African freshwater fishes, but their impact remains unclear. We revisit the phylogeographic relationships and diversification timelines of Cobitis (spined loaches, family Cobitidae) on both sides of the Strait of Gibraltar. Sampling 230 sites across 41 river basins, we analysed genetic variability using haplotype networks of two mitochondrial (Cytb and COI) and two nuclear (S7 and RAG-1) genes. A time-calibrated multilocus phylogeny was constructed and compared with the evolution timeline of the Iberian hydrographic network. Our results indicate that Iberian and North African Cobitis are monophyletic at the mitochondrial, but not at the nuclear level. Three new mitochondrial lineages, potentially new species, were identified in Iberia (2) and Morocco (1). Most Iberian Cobitis show wide distributions and frequent sympatry in major basins. Diversification started in the Mid-Late Miocene (7.9–8.9 Mya), with major speciation during the Late Miocene–Pliocene transition (6.5–5.7 Mya). Palaeographic changes in river basins, from endorheic to exorheic regimes, probably affected Cobitis speciation. Tectonic strike-slip faults probably influenced isolation, genetic mixing, and incomplete lineage sorting, particularly along Atlantic margins. These results highlight the interplay of geological and evolutionary processes in shaping freshwater fish diversity.Field work and laboratory research was supported by the FCT projects FRH/BPD/14637/2003, GENESTREAM (SFRH/BD/10330/2002), FRESHING (PTDC/AAG-MAA/2261/2014), FRESHCO (PTDC/AGR-FOR/1627/2014), UIDB/04033/2020, 2020.04637.BD, and the MICIU projects UIDP/04033/2020, PID2023-147743NB-I00. The FCT supported the Stimulus of Scientific Employment contract of AFF (2020.03872.CEECIND) and MLL (2020.03608.CEECIND)
Adherence to the mediterranean diet and the risk of metabolic syndrome: a preliminary study
No full textThe Mediterranean Diet has been widely recognized for its protective effects against cardiovascular and metabolic diseases (Zazpe et al., 2008). Metabolic syndrome, often defined as the simultaneous occurrence of health-related
risk factors, is a growing concern in ageing populations (Swarup et al., 2024). Understanding how dietary patterns influence metabolic health in older adults is essential for promoting healthy
ageing and preventing disease. Objectives: To explore the association between adherence to the Mediterranean Diet and health-related risk factors among older adults. Methods: A crosssectional study was employed. Self-administered questionnaires were used to collect participant data and assessed for sociodemographic characteristics, self-reported health status,
presence of chronic diseases. Diet adherence was evaluated through the PREDIMED instrument (Zazpe et al., 2008). Metabolic Syndrome was inferred following cut-off values defined by The Third Report of the National Cholesterol
Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Cleeman, 2001).
Blood collection for laboratory tests was performed following WHO guidelines. Informed consent obtained from all participants. Study approved by Ethical Council of Unidade Local
de Saúde do Nordeste, Nº41/2024. Results: Ten participants, aged 69 to 81, adhere to the study. Most were female (90%), with 70% reporting at least one chronic disease. Abdominal obesity
was noted in 40%, and 10% had elevated triglycerides, while 20% had high blood pressure. Approximately 50% of individuals exhibited a high level of Diet adherence, while 40% demonstrated
moderate and low adherence. No participants met the criteria for Metabolic Syndrome. Statistically significant associations were
found between adherence to the Mediterranean Diet and the presence of chronic disease (r=0.869, p<0.01), and an inverse correlation with Mediterranean Diet score and the number of
Metabolic Syndrome criteria (r=–0.707, p<0.05). Moreover, the Mediterranean diet score was inversely associated with cholesterol (r=–0.740, p<0.05). Conclusions: While no participants fulfilled the criteria for metabolic syndrome,
individual risk factors were present in the sample. Higher adherence to the Mediterranean Diet was associated with fewer metabolic risk factors and better overall health indicators. These preliminary findings suggest that dietary patterns may play a key role in the metabolic health of older adults and warrant further investigation with a larger sample
Óleo Essencial de Sementes de Funcho (Foeniculum vulgare Mill): avaliação do potencial de aplicação em aromaterapia e cosmética
No full textAtualmente verifica-se um crescente interesse no estudo de óleos essenciais devido às suas propriedades biológicas e possíveis aplicações na indústria alimentar, farmacêutica e cosmética. O óleo essencial de sementes de funcho (Foeniculum vulgare Mill) é utilizado na culinária e também em chás devido ao seu agradável odor. O objetivo deste estudo foi avaliar o benefício da aplicação de óleo essencial de sementes de funcho (OEF) a nível fitoterapêutico e cosmético.
O OEF foi obtido por hidrodestilação e a sua composição química determinada. A nível fitoterapêutico, avaliou-se o efeito da aromaterapia na ansiedade e qualidade de vida e do sono em dois grupos de indivíduos: “Grupo Massagem” e “Grupo Aroma” (aplicação do OEF a 1,6%). Paralelamente, a toxicidade do OEF foi avaliada no modelo Artemia franciscana. Foi depois desenvolvida uma formulação cosmética e avaliada a sua estabilidade, atividade antimicrobiana e irritação ocular.
O composto maioritário do OEF foi o trans-anetol com uma percentagem de 78,2%. Os resultados do ensaio de aromaterapia mostraram uma diminuição mais evidente na Ansiedade-E no “Grupo Aroma” comparativamente ao “Grupo Massagem” com diferenças entre o Questionário 3 e 1 de -5,89 ± 14,38 e 0,1 ± 15,78, respetivamente. Na Ansiedade-T a maior diferença foi observada no Questionário 4-1 no “Grupo Massagem” com valor de -3,75 ± 17,77, no “Grupo Aroma” a maior diferença observada ocorreu entre o Questionário 1 e 2 com um valor de -2,42 ± 13,59. Relativamente ao Índice de bem-estar, o “Grupo Massagem” teve um aumento maior com a diferença de 2,30 ± 6,67 no Questionário 2-1 em relação ao “Grupo Aroma”. Na qualidade de sono houve também um aumento maior no “Grupo Massagem” comparativamente ao “Grupo Aroma” com diferença entre o Questionário 1 e 3 de -2,90 ± 4,46 e -1,69 ± 4,80, respetivamente. Em relação à formulação cosmética, no teste acelerado, verificou-se apenas um aumento da intensidade do aroma no teste organolético. O pH diminuiu para 5,2, a viscosidade aumentou o valor da densidade diminui para 0,42 g/ml comparativamente ao valor de T0. À temperatura ambiente no escuro e na luz e a 4°C, no teste espetrofotométrico, houve aumento das absorvâncias máximas em todas as condições de teste no T30 em relação ao T0. No teste de viscosidade verificou-se uma diminuição no T30 nas amostras à temperatura ambiente ao escuro e a 4°C mantendo-se idêntica à temperatura ambiente na luz comparativamente ao T0. No teste de cor ocorreu uma diminuição no valor de L* (perda de luminosidade) e no valor de b*, (amostra menos amarela). Os valores de pH variaram entre 5,1 e 5,6, e a densidade entre 0,91 e 1,15 g/ml. No teste com luz verificou-se ressecamento das amostras no T15 que se manteve constante no T30. O teste ocular HET-CAM demonstrou que a formulação cosmética não tinha potencial irritativo. A formulação cosmética não apresentou atividade contra a Propionibacterium acne. No Challenge Test apenas se verificou eficácia do OEF contra a A. brasiliensis. O teste de toxicidade com a Artemia franciscana indicou toxicidade elevada do OEF com valor de LC50 < 100 μg /ml.
O presente estudo demonstrou efeitos interessantes do OEF quando aplicado em aromaterapia, podendo ser também proposto como um ingrediente de produtos cosméticos.Presently, we can verify a growing interest in the study of essential oils due to their biological properties and possible applications in the food, pharmaceutical and cosmetic industries. Fennel seed oils (Foeniculum vulgare Mill) is used in culinary and teas due to its pleasant aroma. The goal of this study is to analyse the benefits of fennel seed essential oil application (FSO) at the phytotherapeutic and comestic level.
FSO is obtained by hydrodestilation and the determined chemical composition. At the phytotherapeutic level, the effects of aromatheraphy; quality of life and quality sleep was evaluated in two distinct groups of individuals: “Massage Group” and “Aroma Group” (FSO application at 1,6%). In parallel, FSO’s toxicity was evaluated in the Artemia franciscana model. Consequently, a cosmetic formula was developed, evaluating the stability, antimicrobial ativity and ocular irritation.
The main compound of FSO was trans-anetol with a percentage of 78,2%. The aromatherapy testing results showed a more significant diminishing effect in the Anxiety- E parcel of the “Aroma Group” when comparing to the “Massage Group”, with differences between the Questionnaire 3 and 1 and values of -5,89 ± 14,38 and 0,1 ± 15,78, respectively. In Anxiety-T the largest difference was observed in the Questionnaire 4-1 in the “Massage Group”, with the value of -3,75 ± 17,77. In the “Aroma Group” the largest difference ocurred between the Questionnaire 1 and 2 with the value of -2,42 ± 13,59. Relatively to the well-being index, the “Massage Group” had a bigger increase with a difference of 2,30 ± 6,67 in the Questionnaire 2-1 when comparing to the “Aroma Group”. In quality of sleep, the “Massage Group” showed once again a bigger increase when compared to the “Aroma Group”, with the difference between the Questionnaire 1 and 3 of -2,90 ± 4,46 and -1,69 ± 4,80; respectively. When it comes to the cosmetic formulation, in the accelerated test, only the intensity of the aroma in the organoleptic test had an increase. pH diminished to 5,2, viscosity increased and the value of the density decreased to 0,42 g/ml when compared to the valeu of T0. In room temperature and absence of light and with light and a temperature of 4oC, the spectrophotometric test revealed an increase in the max absorbances in all conditions of the T30 test, when comparing to T0. In the viscosity test there was a decrease on T30, specifically on the samples at room temperature and absence of light and with light and a temperature of 4oC, showing identical values to T0 at room temperature and light. In the color test a decrease ocurred in the L* value (loss of luminosity) e the b* value, (sample less yellow). The pH values varied between 5,1 and 5,6 and the density between 0,91 and 1,15 g/ml. In the testing with light it was verified a sample dryness on T15 that remained constant in T30. HET-CAM ocular test demonstrated that the cosmetic formulation had no irritating potencial. The cosmetic formulation did not present activity again Propionibacterium acne. In the Challenge Test, FSO presented efficiency only against A. brasiliensis. Toxicity test with Artemia franciscana showed elevated FSO toxicity with values in the order of LC50 < 100 μg /ml.
The present study indicated interesting effects of FSO when applied in aromatherapy, with the capability of also being presented as a cosmetic product ingredient
CFD and experimental investigation of channel diameter effects in structured internally cooled grinding wheels
No full textEfficient cooling and lubrication are critical in grinding due to the high specific energy and limited contact area involved. Conventional external methods often fail to penetrate the air barrier formed by the rotating wheel, leading to excessive heat generation and reduced process stability. To overcome this limitation, this study investigates vitrified alumina grinding wheels with internal cooling channels designed for directed fluid delivery. Three structured configurations were developed, all with identical total outlet area (similar to 54 mm(2)) but different channel diameters (0.6, 1.0, and 1.5 mm), to isolate the effect of channel size on fluid flow and grinding behavior. Computational fluid dynamics (CFD) simulations were performed to assess outlet velocity and surface coverage, while grinding tests quantified tangential and normal forces, temperature variation (Delta T), force ratio (F-t/F-n), and specific grinding energy. Narrow channels provided uniform surface coverage but limited jet velocity due to higher hydraulic resistance, whereas wider channels enhanced outlet velocity at the expense of flow uniformity. The intermediate configuration (& Oslash; 1.0 mm) yielded the most balanced performance, achieving up to 38 % lower tangential force and 41 % lower temperature than the & Oslash; 0.6 mm design, while maintaining low specific energy across all depths of cut. Correlation between CFD and experimental results confirmed that both jet intensity and spatial distribution govern cooling and lubrication efficiency. These insights support the design of more efficient and sustainable grinding wheels through tailored channel geometries.This work was supported by FCT (Foundation for Science and Technology) national funds, under the national support to R&D units grant, through the reference project UIDB/04436. The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES (PIDDAC) to CIMO (UIDB/00690/2020 and UIDP/00690/2020) and SusTEC (LA/P/0007/2020). This work is within the scope of Sharlane Costa Ph.D. degree, in progress, financially supported by the Portuguese Foundation for Science and Technology (FCT) through the Ph.D grant reference 2021.07352.BD (DOI:https://doi.org/10.54499/2021.07352.BD). Paulina Capela acknowledges the financial support from FCT through the doctoral grant 2024.01273.BDANA
Tunable physicochemical properties of PDMS@nanoparticle composites: modifications, mechanisms, and emerging applications
No full textPolydimethylsiloxane@nanoparticles (PDMS@NPs) composites represent a versatile class of advanced elastomers whose physicochemical behavior can be finely tuned through nanoscale interfacial design and nanofiller morphology. Owing to their inherent flexibility, transparency, and chemical stability, PDMS based systems have emerged as model platforms for developing multifunctional materials with optimized mechanical, thermal, electrical, optical, acoustic and wetting properties. This review systematically elucidates the structure property relationships in PDMS@NPs composites and the interaction mechanisms between NPs and polymer chains that enable tunable control over bulk and interfacial behavior, with particular emphasis on how NPs dimensionality and aspect ratio (0D, 1D, and 2D fillers) regulate stress transfer, transport pathways, and functional interconnectivity within the matrix. Three main NP incorporation strategies, (namely, physical mixing of presynthesized NPs, in situ synthesis on cured PDMS, and in situ formation within uncured matrices) are critically compared in terms of interfacial coupling, dispersion stability, and processing scalability. Particular attention is given to how interfacial engineering, nanofiller morphology, and hierarchical architecture govern stress transfer, phonon transport, charge percolation, and optical or surface responses. In addition, a property design prospective is presented that links interphase design and nanofiller morphology to mechanical, thermal, electrical, optical, acoustic and wetting-controlled surface properties. This review further critically examines the limiting factors that reduce the applicability of PDMS@NPs composites, including performance degradation, interface instability, and limited recyclability, as well as long-term stability under mechanical, thermal, optical, and environmental conditions. Emerging directions such as green filler synthesis, recyclable PDMS matrices, dynamic and hi-erarchical interphases, and predictive modeling of morphology-dependent dynamic interfaces are outlined. Overall, this review provides a comprehensive and critical perspective on PDMS@NPs composites as a next generation of soft, functional, and sustainable elastomeric materials, opening new avenues for advances in flexible electronics, soft robotics, biomedical devices, and adaptive coatings.The authors acknowledge the partial financial support of the project 2022.06207.PTDC (https://doi.org/10.54499/2022.06207.PTDC), COMPETE2030-FEDER-00771500 and COMPETE2030-FEDER-00689800 through national funds (OE), within the scope of the Scientific Research and Technological Development Projects (IC&DT) program in all scientific domains (PTDC), through Fundação para a Ciência e Tecnologia (FCT). The authors also acknowledge the partial financial support by national funds through FCT/MECI/MCTES (PIDDAC): MEtRICs, UID/04077/2025; CEFT, UID/00532/2025; CMEMS, UID/04436/2025; CIMO, UID/00690/2025, UID/PRR/00690/2025, SusTEC LA/P/0007/2020 and LA/P/0045/2020. Glauco Nobrega acknowledges the financial support by the doctoral grant PRT/BD/153088/2021 (https://doi.org/10.54499/PRT/BD/153088/2021), financed by FCT, and with funds from MCTES/República Portuguesa, under the MIT Portugal Program. Inês Afonso and Lucas Neves acknowledge the financial support by FCT, of the doctoral grant 2024.05919.BDANA and 2025.00900.BDANA, respectively. Andrews Souza acknowledges financial support from FCT, under grant reference 2021.07961.BD (DOI: https://doi.org/10.54499/2021.07961.BD). J.L. Diaz de Tuesta acknowledges the financial support through the program of Atracción al Talento of Comunidad de Madrid (Spain) and Consolidación Investigadora 2024 of Agencial Estatal de Investigación for the individual research grants 2022-T1/AMB-23946 and CNS2024-154264, respectively
Influence of Time and Temperature Variables on the Heat Treatment of an AL-MG SI Alloy
No full textThis study investigates the effect of time and temperature on the heat treatment of 6082 Al-Mg-Si alloy. Solubilization, quenching, and artificial aging were performed under parameter combinations defined using the Taguchi method. Mechanical testing supported the development of a multiple linear regression model, which identified aging temperature as the most significant factor influencing ultimate tensile strength and yield strength. High aging temperatures promoted coarse precipitate formation and reduced strength, while lower temperatures minimized this effect and maintained or improved mechanical performance. The results demonstrate the potential of combining statistical design with predictive modeling to optimize heat treatment parameters and enhance alloy performance for industrial applications
Nutritional and biochemical profile and bioactive properties of four Greek local landraces of onion
No full textThe preservation of genetic diversity of horticultural crops is essential for modern agroecosystems that face pressure from climate change and the intensification of crop production.
Methodology In the present work, the nutritive value, chemical profile and bioactive properties of four Greek onion local landraces were investigated for the first time. The tested genotypes included three local landraces originated from the region of Thiva, one landrace collected from Evoia, as well as one commercial cultivar which was used as the control treatment. All the genotypes were assessed in terms of nutritional value, chemical composition and bioactivities.
Results and discussion Our results indicate a high variability in the nutritive value and the chemical profile of the studied genotypes, while varied bioactive properties were also recorded. The bulbs of the local landrace ON5 were the richest in polyphenols and quercetin in particular, a finding which was also accompanied by the highest antioxidant activity. On the other hand, the commercial cultivar was the richest in total and individual free sugars, as well as in total dietary fibers and total organic acids, results which indicate a sweeter taste and higher pungency. In conclusion, the studied landraces showed promising properties and they could be further valorized through the implementation of breeding programs aiming to produce new elite onion genotypes with high nutritional and bioactive potential.The author(s) declared that financial support was received for this work and/or its publication. This work was financially supported by national funds through FCT/MCTES (PIDDAC): CIMO, UIDB/00690/2020 (DOI: 10.54499/UIDB/00690/2020) and UIDP/00690/2020 (DOI: 10.54499/UIDP/00690/2020); and SusTEC, LA/P/0007/2020 (DOI: 10.54499/LA/P/0007/2020). The authors are also grateful to the National funding by FCT, through the institutional to LB (CEEC-INST, DOI: 10.54499/CEECINST/00107/2021/CP2793/CT0002) and AF (2023.11031.TENURE.014), and the PhD fellowship (2024.01522.BD) of DA.info:eu-repo/semantics/publishedVersio
Effects of hydrotherapy on gait control in older adults with neurological conditions: A systematic review
Full text linkHydrotherapy appears safe and more effective than conventional physiotherapy for improving gait control, balance, and mobility in older adults with neurological impairments. Its buoyancy and resistance effects facilitate motor re-education and confidence in movement. Integrating aquatic therapy into neurorehabilitation programs may enhance outcomes and quality of life, although long-term follow-up studies are still needed