Applied Sciences

14 pages, 1721 KiB

Open AccessArticle

Informational and Topological Characterization of CO and O₃ Hourly Time Series in the Mexico City Metropolitan Area During the 2019–2023 Period: Insights into the Impact of the COVID-19 Pandemic

by Alejandro Ramirez-Rojas, Paulina Rebeca Cárdenas-Moreno, Israel Reyes-Ramírez, Michele Lovallo and Luciano Telesca

Appl. Sci. 2025, 15(16), 8775; https://doi.org/10.3390/app15168775 (registering DOI) - 8 Aug 2025

Abstract

The main anthropogenic sources of air pollution in big cities are vehicular traffic and industrial activities. The emissions of primary pollutants are produced directly from the combustion of fossil fuels of vehicles and industry, whilst the secondary pollutants, such as tropospheric ozone ( [...] Read more.

The main anthropogenic sources of air pollution in big cities are vehicular traffic and industrial activities. The emissions of primary pollutants are produced directly from the combustion of fossil fuels of vehicles and industry, whilst the secondary pollutants, such as tropospheric ozone (

O_{3}

), are produced from precursors like Carbon monoxide (

C O

), among others, and meteorological factors such as radiation. In this study, we analyze the time series of

CO

and

O_{3}

concentrations monitored by the RAMA program between 2019 and 2023 in the southwest of the Mexico City Metropolitan Area, encompassing the COVID-19 lockdown period declared from March to September–October 2020. After removing cyclic patterns and normalizing the data, we applied informational and topological methods to investigate variability changes in the concentration time series, particularly in response to the lockdown. Following the onset of lockdown measures in March 2020—which led to a significant reduction in industrial activity and vehicular traffic—the informational quantities

N_{X}

and Fisher Information Measure (FIM) for

CO

revealed significant shifts during the lockdown, while these metrics remained stable for

O_{3}

. Also, the coefficient of variation of the degree

C V_{k}

, which was defined for the network constructed for each series by the Visibility Graph, showed marked changes for

CO

but not for

O_{3}

. The combined informational and topological analysis highlighted distinct underlying structures:

CO

exhibited localized, intermittent emission patterns leading to greater structural complexity, while

O_{3}

displayed smoother, less organized variability. Also, the temporal variation of the FIM and

N_{X}

provides a means to monitor the evolving statistical behavior of the

C O

and

O_{3}

time series over time. Finally, the Visibility Graph (VG) method shows a behavioral trend similar to that shown by the informational quantifiers, revealing a significant change during the lockdown for

C O

, although remaining almost stable for

O_{3}

. Full article

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13 pages, 1225 KiB

Open AccessArticle

The Effect of Practicing Selected Sports on the Value of the Center of Pressure (COP): A Pilot Study

by Arletta Hawrylak, Aneta Demidaś and Adam Hawrylak

Appl. Sci. 2025, 15(16), 8774; https://doi.org/10.3390/app15168774 (registering DOI) - 8 Aug 2025

Abstract

The purpose of this study was to determine whether training for a marathon and powerlifting could affect the value of the center of pressure (COP) in static and dynamic testing assessed with the Free Med ground reaction force platform. A baropodometric mat was [...] Read more.

The purpose of this study was to determine whether training for a marathon and powerlifting could affect the value of the center of pressure (COP) in static and dynamic testing assessed with the Free Med ground reaction force platform. A baropodometric mat was used to evaluate COP values, using Free Step computer software. The study was performed in three groups: marathon runners (M, n = 31), powerlifters (PL, n = 24), and a control group (C, n = 30). Basic descriptive statistics (mean ± standard deviation) were calculated for the COP in the static, anteroposterior (AP), and mediolateral (ML) directions, followed by dynamic test variables for the dominant (D) and non-dominant (ND) lower limbs. In each of the three study groups, one-factor ANOVA, two-factor MANOVA, and r-Pearson correlation coefficients between COP and D lower limb, as well as between COP and ND lower limb, were calculated. No statistically significant differences were observed between the means of the COP in the groups studied in the static test. A statistically significant difference between the COP of the D and ND lower limbs (p < 0.001) was observed in the dynamic test only in the M group. In both the C and PL groups, a significant relationship was observed between the two variables for the parameter of sway distance between the lower limbs (r = 0.75; p < 0.001 and r = 0.73; p < 0.001). Only in the M group were statistically significant differences found between the D and ND lower limbs in the dynamic study (p < 0.001). These athletes developed specific postural strategies characterized by the difference between the length of the sway path between the D and ND lower limbs. Further research is needed in these athlete groups to determine whether practicing these sports can affect the distribution of foot pressure on the ground. Full article

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19 pages, 3807 KiB

Open AccessArticle

The Irrigation Water pH Has a Dominant Impact on the Growth and Stress Markers of Bigleaf Hydrangea

by Monika Marković, Vlatko Galić, Veronika Težak, Marija Ravlić, Željko Barač, Irena Jug and Lucija Galić

Appl. Sci. 2025, 15(16), 8773; https://doi.org/10.3390/app15168773 (registering DOI) - 8 Aug 2025

Abstract

Hydrangeas are economically important ornamental plants whose growth and flower characteristics depend on irrigation water quality (IWC), i.e., hydrogenionic potential (pH) and electrical conductivity (EC). Unfavorable IWC causes plant stress, reduced growth and tissue damage, leading to physiological responses such as proline accumulation [...] Read more.

Hydrangeas are economically important ornamental plants whose growth and flower characteristics depend on irrigation water quality (IWC), i.e., hydrogenionic potential (pH) and electrical conductivity (EC). Unfavorable IWC causes plant stress, reduced growth and tissue damage, leading to physiological responses such as proline accumulation (for stress protection) and increased malondialdehyde (MDA, an indicator of damage). A greenhouse pot experiment was conducted as a three-factor study in three replicates. The study examined the impact of different pH levels (4, 5, and 6, compared to a control treatment of pH 7), and EC levels (2, 3, and 4 dS m⁻¹, compared to a control treatment of 1 dS m⁻¹) on biomass, i.e., plant height (cm), stem number (n), flower number (n), leaf number (n) and weight (g), flower weight (g) and diameter (cm), growth index (GI) and the proline and MDA concentrations in two hydrangea varieties (Early Blue and Bianco). Study results showed a significant impact of (p = 0.0001) pH on all tested morphological properties, except flower diameter. Notably, pH 6 maximized biomass accumulation, i.e., plant height (56.6 cm), leaf number (n = 97) and weight, flower weight (156.8 g), and GI (36 cm), while pH 4 promoted the highest number of flowers (n = 10) and stems (n = 10), which are both crucial for aesthetic and market value. EC significantly (p = 0.001) affected plant height (EC 2 = 56.3 cm), flower (EC 2 = 181.9 g) and leaf weight (EC 3 = 148.2 g), and growth index (EC 2 = 27.2 cm). The lowest stress indicators (proline and MDA concentrations) were recorded at pH 6 (MDA = 0.215 µmol g⁻¹ FW, proline = 659.5 µmol g⁻¹ FW) and EC 2 (MDA = 0.551 µmol g⁻¹ FW, proline = 4068.2 µmol g⁻¹ FW). The highest MDA and proline concentrations were observed under extreme conditions of pH 4 (MDA = 1.257 µmol g⁻¹ FW, proline = 12,811.7 µmol g⁻¹ FW) and EC 4 (MDA = 0.692 µmol g⁻¹ FW, proline = 4880.8 µmol g⁻¹ FW). No significant effect of variety on proline and MDA concentrations was observed, while the highest GI was recorded for the Early Blue variety (24.3 cm). This research identifies pH 6 and EC 2 as key conditions for optimizing hydrangea biomass and reducing stress, offering practical guidelines for growers. The findings provide a foundation for developing precise irrigation water quality strategies in the commercial production of ornamental plants. Full article

(This article belongs to the Special Issue Advances in Plant Physiology and Their Applications)

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22 pages, 13717 KiB

Open AccessArticle

In Silico Identification of Six Mushroom-Derived Sterol and Triterpenoid Compounds as Potential P-Glycoprotein Modulators in Multidrug Resistance

by Jéssica Fonseca, Carlos S. H. Shiraishi, Rui M. V. Abreu, Sara Ricardo and Josiana A. Vaz

Appl. Sci. 2025, 15(16), 8772; https://doi.org/10.3390/app15168772 (registering DOI) - 8 Aug 2025

Abstract

The overexpression of P-glycoprotein (P-gp) is often directly related to multidrug resistance (MDR), one of the greatest challenges in cancer treatment. This transmembrane efflux pump decreases the intracellular concentrations of chemotherapy drugs, reducing their effectiveness and resulting in treatment failure. This work used [...] Read more.

The overexpression of P-glycoprotein (P-gp) is often directly related to multidrug resistance (MDR), one of the greatest challenges in cancer treatment. This transmembrane efflux pump decreases the intracellular concentrations of chemotherapy drugs, reducing their effectiveness and resulting in treatment failure. This work used in silico methods to assess the potential of bioactive chemicals produced from mushrooms as P-gp modulators. A database comprising 211 bioactive compounds from mushrooms was investigated using molecular docking and virtual screening techniques against the P-gp structure. The compounds ergosta-4,6,8(14),22-tetraen-3-one, lucidumol A, (22E,24S)-ergosta-4,22-dien-3-one, antcin K, 3,11-dioxolanosta-8,24(Z)-diene-26-oic acid, and (22E)-19-norergosta-5,7,9,22-tetraen-3

β

-ol were identified as the six best candidates from our database of mushroom compounds based on their binding affinities, toxicity predictions, and pharmacological properties assessed through ADME analyses (absorption, distributions, metabolism, and excretion). These six compounds exhibited strong binding affinities, with binding energies ranging from −12.31 kcal/mol to −10.93 kcal/mol, all showing higher affinities than the control, tariquidar, which had a binding energy of −10.78 kcal/mol. Toxicity predictions indicated favorable safety profiles for all six, while ADME analyses found that all six compounds had high oral bioavailability and a low probability of acting as P-gp substrates. These results position bioactive mushroom compounds, particularly these six, as promising P-gp modulators, suggesting positive outcomes in cancer treatment. Full article

(This article belongs to the Special Issue Anticancer Drugs: New Developments and Discoveries)

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20 pages, 6165 KiB

Open AccessArticle

Research on Intelligent Predictions of Surrounding Rock Ahead of the Tunnel Face Based on Neural Network and Longitudinal Deformation Curve

by Shuai Shao, Renjie Song, Yimin Wu, Zhicheng Zhang, Helin Fu, Yichen Peng, Zelong Li and Yao Liu

Appl. Sci. 2025, 15(16), 8771; https://doi.org/10.3390/app15168771 (registering DOI) - 8 Aug 2025

Abstract

Traditional methods for predicting surrounding rock grades ahead of tunnel faces encounter challenges: image-based approaches are susceptible to environmental interference, while parameter-based classification may disrupt construction. This study proposes an intelligent rock grade identification method by integrating longitudinal displacement profile (LDP) evolution patterns [...] Read more.

Traditional methods for predicting surrounding rock grades ahead of tunnel faces encounter challenges: image-based approaches are susceptible to environmental interference, while parameter-based classification may disrupt construction. This study proposes an intelligent rock grade identification method by integrating longitudinal displacement profile (LDP) evolution patterns with deep learning. First, the numerical model was validated against V-D theoretical curves, and LDP evolution laws were systematically analyzed for three rock types (GSI = 15, 30, 50) under nine geological combinations. The results indicate that (1) homogeneous strata exhibit deformation peaks followed by declines; (2) GSI = 15 strata show significantly larger deformations; and (3) stratified schemes display pre-interface deformation peaks and post-interface deformation controlled by subsequent lithology. A novel hybrid neural network was developed to classify strata using LDP curves as input. The model achieved 93.25% training accuracy and 91.20% validation accuracy. Ablation experiments demonstrated their superiority over the other four models with partial module deletions, achieving improvements in test accuracy of 3.24%, 3.08%, 4.16%, and 6.48%, respectively, compared to those models. This lightweight solution effectively overcomes the limitations of manual expertise dependency in conventional models and environmental sensitivity in visual methods. By synergizing LDP evolution analysis with deep learning, this framework provides a reliable approach for real-time rock grade prediction during tunnel advancement. Full article

(This article belongs to the Section Civil Engineering)

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12 pages, 732 KiB

Open AccessArticle

Ecotoxicological Assessment of Soils Reclaimed with Waste

by Marta Bik-Małodzińska, Kamila Rybczyńska-Tkaczyk and Anna Jakubczyk

Appl. Sci. 2025, 15(16), 8770; https://doi.org/10.3390/app15168770 (registering DOI) - 8 Aug 2025

Abstract

This study aimed to conduct an ecotoxicological assessment of soils reclaimed with waste, assessing the treatments’ impacts on both plants and the soils themselves. The reclamation experiment was conducted on the former sulfur mine “Jeziórko”. A microplot experiment was established on a slightly [...] Read more.

This study aimed to conduct an ecotoxicological assessment of soils reclaimed with waste, assessing the treatments’ impacts on both plants and the soils themselves. The reclamation experiment was conducted on the former sulfur mine “Jeziórko”. A microplot experiment was established on a slightly clayey sand to assess the possibilities of different technologies for applying mineral wool to degraded soil. The highest toxicity level was observed in the unreclaimed degraded soil. The M index value was 200%, indicating the death of half of the test organisms. At the same time, root growth inhibition reached 75%, indicating significantly limited root system development. The addition of lime and mineral fertilizers contributed to a slight reduction in toxicity—M = 250%, GI = 50%. Application of sewage sludge at a dose of 100 Mg·ha⁻¹ significantly reduced environmental toxicity—M decreased to 333.3% and 500%, and GI to 35% and 10%, respectively. The addition of mineral wool resulted in further improvement. The best results were achieved in the variant where the soil was enriched with lime, sewage sludge and a large volume of mineral wool (400 m³·ha⁻¹). The GI and M levels indicate that, in this variant, soil toxicity was practically eliminated. Full article

(This article belongs to the Special Issue Degraded Soil Treatment and Influence on Biodiversity)

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16 pages, 634 KiB

Open AccessReview

White Noise Exemplifies the Constrained Disorder Principle-Based Concept of Overcoming Malfunctions

by Sagit Stern Shavit and Yaron Ilan

Appl. Sci. 2025, 15(16), 8769; https://doi.org/10.3390/app15168769 (registering DOI) - 8 Aug 2025

Abstract

The Constrained Disorder Principle (CDP) characterizes systems by their inherent variability, which is regulated within dynamic boundaries to ensure optimal function and adaptability. In biological systems, this variability, or “noise”, is crucial for resilience and flexibility at various scales, ranging from genes and [...] Read more.

The Constrained Disorder Principle (CDP) characterizes systems by their inherent variability, which is regulated within dynamic boundaries to ensure optimal function and adaptability. In biological systems, this variability, or “noise”, is crucial for resilience and flexibility at various scales, ranging from genes and cells to more complex organ systems. Disruption of the boundaries that control this noise—whether through amplification or suppression—can lead to malfunctions and result in pathological conditions. White noise (WN), defined by equal intensity across all audible frequencies, is an exemplary clinical application of the CDP. It has been shown to stabilize disrupted processes and restore functional states by utilizing its stochastic properties within the auditory system. This paper explores WN-based therapies, specifically for the masking, habituation, and alleviation of tinnitus, a subjective perception of sound. It describes the potential to improve WN-based therapies’ effectiveness by applying the CDP and CDP-based second-generation artificial intelligence systems. Understanding the characteristics and limitations of these approaches is essential for their effective implementation across various fields. Full article

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20 pages, 5720 KiB

Open AccessArticle

The Influence of Steel, Glass and Basalt Fibres on Selected Parameters of Construction Mortars

by Anna Kotwa and Iga Jasińska

Appl. Sci. 2025, 15(16), 8768; https://doi.org/10.3390/app15168768 (registering DOI) - 8 Aug 2025

Abstract

Dispersed reinforcement in cement mortars plays a key role in increasing their durability and strength. The fibres act as binding elements in the structure, preventing the development of microcracks that can weaken the material. Fibres increase mechanical strength, elasticity and resistance to tension [...] Read more.

Dispersed reinforcement in cement mortars plays a key role in increasing their durability and strength. The fibres act as binding elements in the structure, preventing the development of microcracks that can weaken the material. Fibres increase mechanical strength, elasticity and resistance to tension and compression, which translates into better physical and mechanical parameters of the material compared to mortars without fibres. The aim of this study was to determine the physical and mechanical parameters of mortars with the addition of currently produced steel, glass and basalt fibres. The influence of the selected fibre type on the compressive and flexural strength, water absorption and capillary rise of mortars was investigated. The rheological properties of the mortars, i.e., consistency and volume density, were also investigated. Compressive and flexural strength was tested after 7, 28 and 56 days, while capillary rise and water absorption were tested after 28 days of curing. The frost resistance of the mortars was also determined. For the mortars tested, correlations were established between compressive strength and flexural strength, as well as between water absorption and capillary pull-up. A full statistical analysis was performed for two parameters, i.e., compressive strength and capillary pull-up. The introduction of basalt fibres into the mortars resulted in an increase in compressive strength by approximately 5% and in flexural strength by 48% after 56 days of curing. A lower mass increase of approximately 30% was also observed in relation to the reference series in the water absorption and capillary pull-up test for the series of mortars with glass fibres. Full article

(This article belongs to the Special Issue Advanced Composite Materials and Structures: Innovations and Applications)

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24 pages, 10793 KiB

Open AccessArticle

Research on Spatial Characteristics and Influencing Factors of Urban Vitality at Multiple Scales Based on Multi-Source Data: A Case Study of Qingdao

by Yanjun Wang, Yawen Wang, Zixuan Liu and Chunsheng Liu

Appl. Sci. 2025, 15(16), 8767; https://doi.org/10.3390/app15168767 (registering DOI) - 8 Aug 2025

Abstract

Urban vitality serves as an important indicator for evaluating the level of urban quality development and sustainability. In response to a series of urban challenges arising from rapid urban expansion, enhancing urban quality and fostering urban vitality have become key objectives in contemporary [...] Read more.

Urban vitality serves as an important indicator for evaluating the level of urban quality development and sustainability. In response to a series of urban challenges arising from rapid urban expansion, enhancing urban quality and fostering urban vitality have become key objectives in contemporary urban planning and development. This study summarizes the spatial distribution patterns of urban vitality at the street and neighborhood levels in the central area of Qingdao, and analyzes their spatial characteristics. A 5D built environment indicator system is constructed, and the effects of the built environment on urban vitality are explored using the Optimal Parameter Geographic Detector (OPGD) and the Multi-Scale Geographically Weighted Regression (MGWR) model. The aim is to propose strategies for enhancing spatial vitality at the street and neighborhood scales in central Qingdao, thereby providing references for the optimal allocation of urban spatial elements in urban regeneration and promoting sustainable urban development. The findings indicate the following: (1) At both the subdistrict and block levels, urban vitality in Qingdao exhibits significant spatial clustering, characterized by a pattern of “weak east-west, strong central, multi-center, cluster-structured,” with vitality cores closely aligned with urban commercial districts; (2) The interaction between the three factors of functional density, commercial facilities accessibility and public facilities accessibility and other factors constitutes the primary determinant influencing urban vitality intensity at both scales; (3) Commercial facilities accessibility and cultural and leisure facilities accessibility and building height exert a positive influence on urban vitality, whereas the resident population density appears to have an inhibitory effect. Additionally, factors such as building height, functional mixing degree and public facilities accessibility contribute positively to enhancing urban vitality at the block scale. (4) Future spatial planning should leverage the spillover effects of high-vitality areas, optimize population distribution, strengthen functional diversity, increase the density of metro stations and promote the coordinated development of the economy and culture. Full article

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Appl. Sci., Volume 15, Issue 16 (August-2 2025) – 9 articles

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