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24 pages, 1974 KB  
Article
Enhancing Stability of Reprocessed Acrylonitrile–Butadiene–Styrene (ABS) Polymers from Sorted WEEE Streams for Filament Extrusion
by Christina Podara, Christos Panagiotopoulos, Dionysia Kouranou, Christos Tsirogiannis, Melpo Karamitrou, Tatjana Kosanovic Milickovic, Stamatina Vouyiouka and Costas Charitidis
Polymers 2026, 18(8), 971; https://doi.org/10.3390/polym18080971 - 16 Apr 2026
Abstract
The mechanical recycling of styrenic polymers from waste electrical and electronic equipment (WEEE) is often limited by thermomechanical degradation occurring during repeated processing. In this work, the degradation behaviour of acrylonitrile–butadiene–styrene (ABS) recovered from sorted WEEE streams was systematically investigated through multiple extrusion [...] Read more.
The mechanical recycling of styrenic polymers from waste electrical and electronic equipment (WEEE) is often limited by thermomechanical degradation occurring during repeated processing. In this work, the degradation behaviour of acrylonitrile–butadiene–styrene (ABS) recovered from sorted WEEE streams was systematically investigated through multiple extrusion cycles, and the effectiveness of antioxidant stabilization was evaluated. Progressive degradation was assessed by chemical structure, rheological, thermal and mechanical testing, and colorimetric analysis. Repeated processing resulted in increased melt flow, altered viscoelastic behaviour, molecular weight reduction, deterioration of mechanical properties, and discoloration. To mitigate these effects, antioxidant-stabilized compounds were prepared and subjected to identical reprocessing pathways. The addition of antioxidants effectively reduced chain scission, stabilized rheological properties, and limited colour changes during reprocessing. Furthermore, the processability of the optimized recycled ABS is demonstrated through filament extrusion for fused filament fabrication, highlighting its potential for high-value additive manufacturing applications. These results demonstrate that appropriate stabilization strategies can significantly enhance the process stability and recyclability of styrenic polymers from WEEE streams, supporting their use in higher-value applications within a circular economy framework. Full article
(This article belongs to the Special Issue Additive Manufacturing of Polymer Based Materials)
36 pages, 1318 KB  
Article
A Three-Step System (Biochar and Sand Filtration with Chlorination) for Handwashing Wastewater Treatment and Possible Water Reuse in Rural Schools
by Jhonny I. Bautista Quispe, Luiza C. Campos, Ondrej Masek and Anna Bogush
Sustainability 2026, 18(8), 3964; https://doi.org/10.3390/su18083964 - 16 Apr 2026
Abstract
School handwashing facilities in rural areas without piped water and drainage systems often discharge wastewater directly into the ground, leading to environmental contamination and loss of a valuable water resource, particularly in water-scarce regions. This study evaluates a decentralised three-stage handwashing wastewater treatment [...] Read more.
School handwashing facilities in rural areas without piped water and drainage systems often discharge wastewater directly into the ground, leading to environmental contamination and loss of a valuable water resource, particularly in water-scarce regions. This study evaluates a decentralised three-stage handwashing wastewater treatment system combining biochar and sand filtration with chlorination. The integrated system effectively improved water quality by reducing turbidity, colour, suspended solids, nutrients, organic matter, and microbial contamination. While biochar and sand filtration provided substantial physicochemical treatment, chlorination was essential to ensure complete microbial inactivation. The treated water met several water quality standards for potable use (handwashing only) set by the World Health Organization (WHO) and the United States Environmental Protection Agency (USEPA) standards. Additionally, it complied with international guidelines for greywater reuse in toilet flushing, irrigation, and floor washing. This innovative water treatment strategy could help clean and reuse handwashing wastewater on-site. This could provide rural schools with clean water to support water needs in water shortage periods, such as hand hygiene, garden irrigation, toilet flushing, and floor washing. Overall, integrating biochar and sand filtration with disinfection could help remote rural schools recover water, advancing towards the achievement of the Sustainable Development Goals (SDG) for good health (SDG 3), clean water and sanitation (SDG 6), and sustainable communities (SDG 11). Full article
14 pages, 978 KB  
Article
Use of Texturised Pea Protein By-Product in High-Protein Bread
by Paloma Franco, Diogo Salvati and Manuel Gómez
Appl. Sci. 2026, 16(8), 3860; https://doi.org/10.3390/app16083860 - 16 Apr 2026
Abstract
There is increasing interest in protein-enriched foods and in the valorisation of by-products from the agri-food sector. This study investigated the incorporation of by-products derived from texturised pea protein production into high-protein bread formulations. Wheat flour was partially replaced (10%) with different protein [...] Read more.
There is increasing interest in protein-enriched foods and in the valorisation of by-products from the agri-food sector. This study investigated the incorporation of by-products derived from texturised pea protein production into high-protein bread formulations. Wheat flour was partially replaced (10%) with different protein sources (gluten, pea protein isolate, pea protein concentrate, and two types of texturised by-products, T60 and T80). In a subsequent trial, blends of gluten with a by-product (T60) or with pea protein concentrate were evaluated at replacement levels of 10, 20 and 30%. Dough mixing properties and bread quality attributes (specific volume, texture and colour) were assessed. All protein sources increased water absorption. Gluten and the protein concentrate also increased kneading time. Gluten and the by-products increased the specific volume of the breads and reduced crumb firmness, whereas the isolate showed the opposite effect. The incorporation of gluten–T60 blends at 30% significantly increased dough water absorption, enhanced specific volume (by more than 80%), reduced crumb firmness, and improved elasticity and cohesiveness compared with the control, while doubling the protein content. However, achieving these improvements delays dough development. These results demonstrate the potential of texturised pea protein by-products as functional ingredients in breadmaking, enabling the development of nutritionally enriched products with favourable technological performance. Full article
(This article belongs to the Special Issue Emerging Trends in Food Safety and Quality Control)
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18 pages, 1102 KB  
Article
Ethyl Oleate Synthesized from Fermentation Waste and Its Stability Evaluation as a Food Additive
by Ana Luiza Fontes, Ana Maria S. Soares, Francisca S. Teixeira, Paula T. Costa, Lígia L. Pimentel and Luís Miguel Rodríguez-Alcalá
Foods 2026, 15(8), 1382; https://doi.org/10.3390/foods15081382 - 16 Apr 2026
Abstract
Ethyl oleate (EO) is an emerging compound used in the food industry as a pre-treatment additive in preservation processes, such as drying, allowing the shelf-life to be extended while preserving the nutritional value of the treated food without compromising consumer safety. Currently, EO [...] Read more.
Ethyl oleate (EO) is an emerging compound used in the food industry as a pre-treatment additive in preservation processes, such as drying, allowing the shelf-life to be extended while preserving the nutritional value of the treated food without compromising consumer safety. Currently, EO is mostly synthesised from edible oils, which raises concerns about competition with the food chain. As an alternative, we previously developed an EO product from a High-Oleic Waste (HOW) obtained from industrial distillation pipelines. Due to the potential application of EO as a food additive, the present study aimed to evaluate its stability throughout its shelf-life in comparison with two commercial benchmarks under accelerated conditions (40 °C, 75% relative humidity, 6 months). Colour parameters (Total Colour Difference and Yellow Index), structural properties by FTIR-ATR, thermal properties by DSC, compositional stability by GC-MS, formation of lipid oxidation products by UV-Vis and cytotoxicity in keratinocytes were evaluated at the beginning (T0) and at the end (T6) of the assay. In general, the synthesised EO showed no considerable changes in the parameters studied after storage, being comparable to the assayed benchmarks. In conclusion, the developed EO was found to be stable during the assayed shelf-life, confirming its potential suitability as an additive for the food industry. Future studies should perform validation in food matrices. Full article
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16 pages, 15962 KB  
Article
SKUF Protocol: Slice, Keep, Unwrap, Fuse—A Pilot Multimodal Approach to Cardiac Innervation Mapping
by Igor Makarov, Olga Solovyova, Anna Starshinova, Dmitry Kudlay and Lubov Mitrofanova
Diagnostics 2026, 16(8), 1178; https://doi.org/10.3390/diagnostics16081178 - 16 Apr 2026
Abstract
Background/Objective: Cardiac innervation plays a critical role in regulating myocardial function and enabling the heart to adapt to physiological and pathological conditions. Although the general features of sympathetic and parasympathetic innervation of the myocardium are well described, the spatial organisation of [...] Read more.
Background/Objective: Cardiac innervation plays a critical role in regulating myocardial function and enabling the heart to adapt to physiological and pathological conditions. Although the general features of sympathetic and parasympathetic innervation of the myocardium are well described, the spatial organisation of nerve fibres within the cardiac muscle remains incompletely characterised. This study aimed to develop and validate the SKUF (Slice–Keep–Unwrap–Fuse) protocol, a multimodal framework for mapping myocardial innervation through the integration of histological data and magnetic resonance imaging (MRI). Methods: The study was performed on the heart of a 7-year-old patient who died from rupture of a cerebral vascular malformation without evidence of cardiovascular disease. Prior to histological processing, post-mortem MRI was performed to provide a precise anatomical reference. The heart was sectioned into sequential transverse rings of 4 mm thickness, yielding 71 paraffin blocks. Histological sections (3 μm) were immunostained with antibodies against UCHL-1 to visualise nerve fibres and scanned using an Aperio AT2 system (20× magnification). Automated image analysis was conducted using the SVSSlide Processor module, which included tissue segmentation, colour-based nerve fibre detection, and sliding-window density mapping. Heatmaps were assembled into ring-based myocardial reconstructions and co-registered with MRI slices using combined rigid and deformable registration, followed by three-dimensional reconstruction of innervation patterns. Results: A higher density of nerve fibres was observed in the right ventricular myocardium compared with the left ventricle, whereas larger nerve trunks were identified in the epicardium of the left ventricle. Quantitative analysis revealed a pronounced longitudinal gradient of innervation, with minimal density in the apical region and progressive increases towards the mid-ventricular segments, where maximal density and spatial organisation of neural structures were observed. The atrioventricular groove exhibited the greatest heterogeneity of innervation due to the presence of large nerve trunks and ganglionated plexuses. Integration of histological maps with MRI enabled three-dimensional visualisation of spatial clusters of nerve fibres. Conclusions: The SKUF protocol provides a robust framework for integrating histological and MRI data to generate three-dimensional maps of myocardial innervation. This approach may facilitate the development of high-resolution anatomical atlases of cardiac innervation and support future studies of neurocardiac mechanisms of arrhythmogenesis and targeted neuromodulation. Full article
(This article belongs to the Special Issue Advances in Cardiovascular Diseases: Diagnosis and Management)
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18 pages, 3040 KB  
Article
Fibre-Enriched Pasta from Wet Milled Royal Quinoa: Technological and Nutritional Characterisation
by Andrea Alonso-Álvarez and Claudia Monika Haros
Foods 2026, 15(8), 1374; https://doi.org/10.3390/foods15081374 - 15 Apr 2026
Abstract
Quinoa fibre-rich fraction (QFi), obtained through wet milling, represents an innovative approach to improving the nutritional and functional quality of cereal-based products. Unlike conventional whole quinoa flour (WhQF), wet milling induces phytate losses during steeping, generating ingredients with enhanced mineral bioavailability. This study [...] Read more.
Quinoa fibre-rich fraction (QFi), obtained through wet milling, represents an innovative approach to improving the nutritional and functional quality of cereal-based products. Unlike conventional whole quinoa flour (WhQF), wet milling induces phytate losses during steeping, generating ingredients with enhanced mineral bioavailability. This study evaluated the incorporation of QFi into wheat pasta, assessing dietary fibre contribution, mineral bioavailability, cooking behaviour, and colour. Six fortified formulations were prepared by partially replacing wheat flour with WQF (white, red, or black) or QFi from the same varieties, with inclusion levels adjusted to provide equivalent dietary fibre across formulations. All quinoa-enriched pastas raised dietary fibre contribution compared with the control. Mineral contents also incremented, with the greatest values observed in formulations containing black quinoa ingredients. Fe and Zn contents were greatest in pastas with black WhQF, while Ca concentration was richer in formulations containing black QFi. Mineral absorption may be partially inhibited in pastas with WhQF, particularly in those containing the red quinoa. In contrast, QFi showed reduced phytate levels, highlighting the nutritional advantage of wet milling. Technologically, quinoa ingredients increased water absorption during pasta cooking. Overall, wet milled QFi provides a novel alternative to WhQF, combining improved mineral bioavailability with suitable technological properties for pasta processing. Full article
(This article belongs to the Section Grain)
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24 pages, 17941 KB  
Article
Bio-Based Pigment Water-Based Inks for Piezoelectric Inkjet Printing
by Jéssica Antunes, Agata Nolasco, Beatriz Marques, Marisa Lopes, Philippe Sarra-Bournet, Augusta Silva, Helena Vilaça and Carla J. Silva
Colorants 2026, 5(2), 13; https://doi.org/10.3390/colorants5020013 - 13 Apr 2026
Viewed by 83
Abstract
The development of bio-based inks represents a promising strategy to reduce the environmental impact of digital printing technologies. This study investigates the formulation and performance of water-based inks incorporating two renewable pigments: a fermentation-derived indigo pigment and a plant-extracted yellow pigment. Special attention [...] Read more.
The development of bio-based inks represents a promising strategy to reduce the environmental impact of digital printing technologies. This study investigates the formulation and performance of water-based inks incorporating two renewable pigments: a fermentation-derived indigo pigment and a plant-extracted yellow pigment. Special attention was given to dispersion optimization of the poorly water-soluble indigo pigment. Extended mechanical dispersion (115 h in a ball mill) proved critical to achieve colloidal stability, enabling the preparation of inks that met standard rheological and physicochemical criteria for inkjet printing with piezoelectric printheads. Both inks were applied on a variety of substrates, including cotton, polyester, leather, and kraft paper, pre-treated, in the case of the textiles, with either a cationic biopolymer or a synthetic polyurethane-based binder. Colorimetric evaluation confirmed effective deposition and uniformity, with the indigo ink producing deep blue hues and superior overall fastness than the yellow ink, particularly in washing and rubbing tests. The yellow pigment ink showed good stability but once applied to the fabric, the resulting print exhibited poor fastness, particularly against light exposure, indicating limited durability of the coloration on the textile. Shelf-life analysis of the indigo ink revealed a decline in viscosity and surface tension over time, though the colour and particle size remained stable, particularly under room temperature conditions. These findings confirm the potential of fermentation-derived indigo as a robust bio-based alternative to synthetic dyes and its superior performance in relation to other nature extracted pigments, which, although facilitating ink preparation due to their higher water solubility, result in lower-fastness prints. Full article
18 pages, 1742 KB  
Article
Thermal Impacts of Stationary Vehicles on Urban Microclimates: Insights from Field Measurements and Exploratory 3D Modelling
by Márcia Matias, Carolina Girotti, Tiago Silva, Gerald Mills, Luiz Fernando Kowalski and António Lopes
Atmosphere 2026, 17(4), 390; https://doi.org/10.3390/atmos17040390 - 12 Apr 2026
Viewed by 326
Abstract
Urban microclimates are traditionally interpreted and modelled based on permanent built surfaces, while semi-permanent elements such as stationary vehicles remain largely overlooked in urban climate studies. Despite their distinct radiative and thermal behaviour and increasing spatial prevalence in contemporary cities, parked vehicles are [...] Read more.
Urban microclimates are traditionally interpreted and modelled based on permanent built surfaces, while semi-permanent elements such as stationary vehicles remain largely overlooked in urban climate studies. Despite their distinct radiative and thermal behaviour and increasing spatial prevalence in contemporary cities, parked vehicles are rarely represented in urban microclimate modelling frameworks. This study provides an exploratory assessment of a commonly used three-dimensional modelling workflow to approximate near-vehicle air temperature patterns at the micro-scale by comparing simulated results with field measurements collected in Lisbon, Portugal. Air temperature was measured in an open parking environment with unobstructed sky exposure, at multiple heights above two black and two white parked vehicles during summer, and corresponding simulated values were extracted at matching locations. Simulated mean air temperatures showed reasonable agreement with observations (MAE = 0.6–0.9 °C; RMSE = 0.7–1.3 °C), suggesting that simplified modelling approaches can reproduce general air temperature patterns under controlled conditions. However, larger localised deviations were observed near vehicle surfaces and rear positions, particularly for dark-coloured vehicles, highlighting limitations in resolving fine-scale radiative and aerodynamic processes. The findings indicate that stationary vehicles can be represented as distinct urban surfaces, while emphasising the need for improved parameterisation to enable their integration into urban microclimate models at larger spatial scales. Full article
(This article belongs to the Section Climatology)
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19 pages, 11288 KB  
Article
Effects of Growing Sites on the Color Variations in Black Locust (Robinia pseudoacacia L.) Wood
by Róbert Németh, László Tolvaj, James K. Govina, Haruna Seidu, Fath Alrhman A. A. Younis and Mátyás Báder
Forests 2026, 17(4), 471; https://doi.org/10.3390/f17040471 - 11 Apr 2026
Viewed by 236
Abstract
The influence of growing site conditions on the chromatic properties of heartwood in black locust (Robinia pseudoacacia L.) cultivar ‘Nyírségi’ sampled from five regions of Hungary was investigated in this study. A total of 23 boards (average age of trees: 34.5 years) [...] Read more.
The influence of growing site conditions on the chromatic properties of heartwood in black locust (Robinia pseudoacacia L.) cultivar ‘Nyírségi’ sampled from five regions of Hungary was investigated in this study. A total of 23 boards (average age of trees: 34.5 years) representing four site types were analyzed by instrumental colorimetry using the CIE Lab system. The overall average color coordinates were L* = 69.9 ± 4.0, a* = 4.0 ± 0.8, and b* = 27.4 ± 2.3. Significant chromatic differences were observed among site types proven by statistical analysis; however, no single site type consistently increased within-site color variability. Average total color differences (ΔE*) ranged from 3.94 to 6.31 across site types, corresponding to “noticeable” to “large” visual differences. Regionally, 89.1% of 55 specimen pairs exhibited clearly perceptible color variation (ΔE* > 2), with 61.8% classified as “large” (ΔE* > 5). Within-tree comparisons revealed ΔE* values of 3.72–3.75 under poor site conditions but <2.0 on good growing sites. The a* and b* components appear with measurable variations across all sites, while the characteristic yellow hue remains distinct and stable independent of site origin due to the high b* value. Full article
(This article belongs to the Special Issue Phenomenon of Wood Colour—2nd Edition)
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29 pages, 2501 KB  
Article
Upcycling Brewer’s Spent Grain and Barley Rootlets by Partial Substitution of Pea Protein Isolate in Extruded High Moisture Meat Analogues
by Ivana Salvatore, Robin Betschart, Claudio Beretta, Maria Rudel, Evelyn Kirchsteiger-Meier, Corinna Bolliger, Matthias Stucki and Nadina Müller
Foods 2026, 15(8), 1327; https://doi.org/10.3390/foods15081327 - 10 Apr 2026
Viewed by 378
Abstract
This study evaluated how a partial substitution of pea protein isolate (PPI) with brewer’s spent grain (BSG) or barley rootlets (BRs) affects high-moisture meat analogues (HMMAs). PPI was substituted with 10% and 20% with BSG or BRs, respectively. Extrudates were produced on a [...] Read more.
This study evaluated how a partial substitution of pea protein isolate (PPI) with brewer’s spent grain (BSG) or barley rootlets (BRs) affects high-moisture meat analogues (HMMAs). PPI was substituted with 10% and 20% with BSG or BRs, respectively. Extrudates were produced on a co-rotating twin-screw extruder at maximum temperatures of 140 °C and 160 °C. Extrudates were assessed for colour, moisture, firmness and fibre morphology. Furthermore, the technofunctional and nutritional properties of the raw materials were determined. Extrudates with BSG produced the darkest colour, whereas PPI and BR formulations exhibited the lightest. A stronger reddish tint was observed at 160 °C, while the colour within the yellow–blue spectrum was largely temperature-independent. Firmness was generally higher at 160 °C, consistent with lower end-product moisture. Side stream addition lowered protein content and weakened fibre formation, with the effect most pronounced for BRs. Overall, formulation was the dominant factor influencing lightness, while temperature modestly increased redness and firmness. Preliminary sensory evaluation supported these trends. Extrudates produced at 140 °C were perceived as having a more fibrous structure. Higher substitution levels resulted in a weaker, more crumbly texture. With respect to the environmental assessment, a 20% replacement of PPI with BRs or BSG reduced overall environmental impacts by up to 19% and climate impacts by up to 16%. With regard to the novel food status, the EU Novel Food Status Catalogue classifies BSG as not novel, whereas BRs are not novel only when used in food supplements. Any other food uses, other than as, or in, food supplements, might considered to be novel and consequently might need to be authorised under the novel food regulation framework prior to market placement. Full article
(This article belongs to the Special Issue Different Strategies for the Reuse and Valorization of Food Waste)
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24 pages, 2991 KB  
Article
Indoor Plant and Mental Wellbeing: Understanding Preferences, Perceptions, and Spatial Arrangements Among University Students
by Bing-Tao Xavier Lee and Koen Steemers
Buildings 2026, 16(8), 1494; https://doi.org/10.3390/buildings16081494 - 10 Apr 2026
Viewed by 411
Abstract
People spend most of their time indoors, highlighting the importance of indoor environmental quality for health and wellbeing. While previous studies have shown that exposure to nature can benefit wellbeing, much of this research has focused on outdoor environments, and less is known [...] Read more.
People spend most of their time indoors, highlighting the importance of indoor environmental quality for health and wellbeing. While previous studies have shown that exposure to nature can benefit wellbeing, much of this research has focused on outdoor environments, and less is known about how indoor plants and their spatial characteristics influence human perceptions and experiences. This paper reports on a survey study exploring how perceived health and wellbeing are influenced by indoor plants and human preferences for their characteristics, spatial arrangement, and other features within indoor environments. Indoor plants serve as visual and multisensory environmental stimuli. By examining the relationship between indoor plants, preferences, perceptions, visual comfort, multisensory experiences, and wellbeing, the study aims to understand these influences. The questionnaires include multiple-choice questions, yes-no questions, and open-ended questions, allowing the collection of both quantitative and qualitative data. The survey findings highlight the unique benefits of indoor plants, emphasising their potential to enhance wellbeing in ways that outdoor nature may not fully replicate in indoor settings. One significant finding of this study is that scattering indoor plants throughout a space can enhance the connection to nature through three-dimensional spatial interaction, potentially improving wellbeing. This arrangement may serve as a bridge to the outdoors, providing a psychological link to the natural environment. Crucial preference factors also include the complexity and coherence of indoor plants’ appearance, such as colour, shape, and size. The results further indicate that students prefer indoor plants over other elements such as cut flowers, fake plants, or artificial plant representations. The findings indicate that caring for indoor plants may foster emotional engagement, a sense of fulfilment, and place attachment through everyday interaction. In public spaces, plants may also enhance feelings of refuge and perceived security. These findings provide practical recommendations for designing indoor environments that enhance student wellbeing and human–environment interaction. Full article
(This article belongs to the Section Architectural Design, Urban Science, and Real Estate)
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32 pages, 1193 KB  
Review
Modelling Skin Pigmentation Using the Monte Carlo Technique: A Review
by Raghda Al-Halawani, Meha Qassem and Panicos A. Kyriacou
Sensors 2026, 26(8), 2337; https://doi.org/10.3390/s26082337 - 10 Apr 2026
Viewed by 158
Abstract
The impact of skin pigmentation on the accuracy of optical biomedical devices has gained increased attention since the COVID-19 pandemic, particularly following evidence of oximetry measurement bias in dark-skinned individuals. Meanwhile, many computational models utilising the Monte Carlo (MC) technique have been developed [...] Read more.
The impact of skin pigmentation on the accuracy of optical biomedical devices has gained increased attention since the COVID-19 pandemic, particularly following evidence of oximetry measurement bias in dark-skinned individuals. Meanwhile, many computational models utilising the Monte Carlo (MC) technique have been developed as a cost-effective and scalable method for investigating these effects. Hence, this review explores the application of the MC technique in modelling skin pigmentation, focusing specifically on how melanin in the epidermis is represented across different studies. First, the biological mechanisms of pigmentation and current stratification methods are outlined to contextualise the variability in skin tone, followed by the principles of MC modelling, including photon scattering, absorption, reflection, and detection. Following a screening and exclusion process, 50 studies were evaluated in terms of how melanin concentration and distribution are incorporated into MC models and their applications, revealing a range of approaches that include analytical equations, experimental optical property measurements, or hybrid methods. The benefits and limitations of each approach is discussed, in addition to emerging advancements such as heterogeneous melanin distribution and the relation between optical properties and skin colour classification scales. Overall, the review outlines the current methodological approaches utilised for skin pigmentation modelling and offers a reference framework for researchers seeking to improve the representation of skin pigmentation in MC-based optical simulations. Full article
(This article belongs to the Special Issue Feature Papers in Biosensors Section 2026)
14 pages, 2711 KB  
Article
Comparison of Oleogels Obtained by Emulsion Template Method Using Low Molecular Weight Hydroxypropyl Methylcellulose (HPMC) with Fish and Vegetable Oils
by Alonso Escobar, Leticia Montes, Amaya Franco-Uría and Ramón Moreira
Gels 2026, 12(4), 319; https://doi.org/10.3390/gels12040319 - 8 Apr 2026
Viewed by 187
Abstract
This work evaluated the influence of oil type (sunflower vs. fish oil) and hydroxypropyl methylcellulose (HPMC) concentration on the properties of oleogels obtained by the emulsion-templated method. Oil-in-water emulsions were prepared and air-dried to produce oleogels containing 2.9–5.8% (w/w) [...] Read more.
This work evaluated the influence of oil type (sunflower vs. fish oil) and hydroxypropyl methylcellulose (HPMC) concentration on the properties of oleogels obtained by the emulsion-templated method. Oil-in-water emulsions were prepared and air-dried to produce oleogels containing 2.9–5.8% (w/w) HPMC. All oleogels exhibited solid-like behaviour, with viscoelastic moduli increasing with polymer concentration, and showed a high thermal stability. At a comparable HPMC content, fish oil oleogels developed stiffer networks than those obtained with sunflower oil. Texture analysis indicated a linear increase in hardness with HPMC content across both oils, while cohesiveness and adhesiveness were more influenced by oil nature. Oil-binding capacity (OBC) increased markedly with polymer content, exceeding 90% in most systems. However, fish oil oleogels consistently showed lower retention. Colour parameters were only slightly affected by HPMC concentration and were mainly determined by the intrinsic colour of each oil. Overall, both oil type and polymer concentration were shown to be critical factors determining the structural, mechanical, and functional characteristics of HPMC-based oleogels, providing useful information for the development of structured lipid systems as potential substitutes for conventional solid fats. Full article
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18 pages, 1090 KB  
Article
Wet Ageing of Chilled Young-Giraffe (Giraffa camelopardalis angolensis) Meat as Influenced by Sex and Muscle
by Bianca L. Silberbauer, Tersia Kokošková, Daniel Bureš, Radim Kotrba, Philip E. Strydom, Martin Kidd and Louwrens C. Hoffman
Foods 2026, 15(7), 1236; https://doi.org/10.3390/foods15071236 - 4 Apr 2026
Viewed by 369
Abstract
This exploratory study determined the ideal ageing period for optimum tenderness of Longissimus thoracis et lumborum (LTL), Semimembranosus (SM) and Biceps femoris (BF) steaks from male and female giraffe. The muscles of eight male and seven female giraffes were divided into 10 steaks [...] Read more.
This exploratory study determined the ideal ageing period for optimum tenderness of Longissimus thoracis et lumborum (LTL), Semimembranosus (SM) and Biceps femoris (BF) steaks from male and female giraffe. The muscles of eight male and seven female giraffes were divided into 10 steaks each, and each steak was randomly allocated to age for 1, 5, 9, 14, 18, 22, 26, 30, 34 or 38 days in vacuum-sealed bags at ±4 °C. At each time point, the pH, surface colour, purge loss, cooking loss and Warner–Bratzler shear force (WBSF) were determined for the respective steaks. Significant interactions between the sex, muscle and days post mortem were observed for the Warner–Bratzler shear force (WBSF), CIE a*, CIE b*, hue-angle, and chroma, while the CIE L* values were affected by an interaction between muscle type and days post mortem. The pH showed three distinct phases: over Days 1–9, the pH (~5.54–5.55) was stable; over Days 14–22, it declined; and the pH dropped more sharply between Days 22 and 26 (~5.42 to ~5.32), before plateauing. The purge loss initially increased rapidly, after which the rate decreased during the ageing period; however, the cooking loss, which was affected only by muscle, remained constant throughout. The tenderness improved until Day 22 across all three muscle types (19.1 ± 0.30 N), after which it plateaued. The colour improved, in terms of redness and saturation, until Day 18 (L* = 44.1 ± 0.29; a* = 15.7 ± 0.19; b* = 15.3 ± 0.08; hue-angle = 44.8 ± 0.39; chroma = 22.0 ± 0.15); thereafter, discolouration occurred. Vacuum-ageing giraffe meat for 14–22 days is recommended to improve tenderness and colour and minimise the negative effects of increased purge loss. This recommendation is based on instrumental measurements with discolouration as a major determinant of acceptability. It is suggested that future research validate this through sensory evaluation and microbial analyses. Full article
(This article belongs to the Section Meat)
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16 pages, 763 KB  
Article
Association Between Parameters of Penile Doppler Ultrasound and Cardiovascular Risk in Patients with Erectile Dysfunction: A Single-Center Retrospective Study
by Andrea Graziani, Andrea Delbarba, Matteo Nardin, Nicola Caretta, Pierfrancesco Palego, Giuseppe Grande, Andrea Di Nisio, Carlo Cappelli and Alberto Ferlin
J. Clin. Med. 2026, 15(7), 2722; https://doi.org/10.3390/jcm15072722 - 3 Apr 2026
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Abstract
Background: Erectile dysfunction (ED) is increasingly recognized as an early manifestation of systemic vascular disease and might represent a window for cardiovascular risk assessment. Dynamic penile colour Doppler ultrasound (PCDU) provides quantitative arterial and venous parameters that could reflect subclinical vascular impairment. [...] Read more.
Background: Erectile dysfunction (ED) is increasingly recognized as an early manifestation of systemic vascular disease and might represent a window for cardiovascular risk assessment. Dynamic penile colour Doppler ultrasound (PCDU) provides quantitative arterial and venous parameters that could reflect subclinical vascular impairment. We investigated the association between PCDU parameters and estimated cardiovascular risk in men with ED. Methods: In this single-center retrospective observational study, 275 men undergoing PCDU for ED were evaluated. Clinical characteristics, biochemical data, and QRISK3 10-year cardiovascular risk scores were collected. Mean peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistive index (RI) were analyzed. Correlation analyses, logistic regression using a QRISK3 ≥ 10% threshold, linear regression models, age-stratified analyses, and receiver operating characteristic (ROC) curve analyses were performed. Results: Patients with impaired PSV (<35 cm/s) were older and exhibited higher QRISK3 scores and a greater prevalence of diabetes mellitus and previous cardiovascular events. Mean PSV was inversely correlated with QRISK3 (r = −0.203, p < 0.01) and was associated with higher cardiovascular risk categories in unadjusted logistic regression (β = −0.016, p = 0.048), but not after adjustment for age and diabetes mellitus. ROC analysis showed modest discrimination of increased cardiovascular risk (AUC = 0.60). The addition of PSV to a model including age and diabetes resulted in minimal improvement in discrimination (AUC 0.966 vs. 0.968). Age-stratified analysis demonstrated a significant association between lower PSV and higher cardiovascular risk only in patients ≤60 years. A progressive increase in QRISK3 was observed according to the number of abnormal Doppler parameters (p = 0.013). Conclusions: PCDU parameters reflect the overall cardiovascular risk burden in men with ED. Although not independent predictors beyond traditional risk factors, penile Doppler abnormalities might identify a vascular phenotype associated with higher estimated cardiovascular risk, particularly in younger individuals. These findings support the role of comprehensive vascular assessment in selected patients with ED. Full article
(This article belongs to the Special Issue Clinical Diagnosis and Management of Erectile Dysfunction)
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