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35 pages, 2895 KiB  
Review
Ventilated Facades for Low-Carbon Buildings: A Review
by Pinar Mert Cuce and Erdem Cuce
Processes 2025, 13(7), 2275; https://doi.org/10.3390/pr13072275 - 17 Jul 2025
Viewed by 671
Abstract
The construction sector presently consumes about 40% of global energy and generates 36% of CO2 emissions, making facade retrofits a priority for decarbonising buildings. This review clarifies how ventilated facades (VFs), wall assemblies that interpose a ventilated air cavity between outer cladding [...] Read more.
The construction sector presently consumes about 40% of global energy and generates 36% of CO2 emissions, making facade retrofits a priority for decarbonising buildings. This review clarifies how ventilated facades (VFs), wall assemblies that interpose a ventilated air cavity between outer cladding and the insulated structure, address that challenge. First, the paper categorises VFs by structural configuration, ventilation strategy and functional control into four principal families: double-skin, rainscreen, hybrid/adaptive and active–passive systems, with further extensions such as BIPV, PCM and green-wall integrations that couple energy generation or storage with envelope performance. Heat-transfer analysis shows that the cavity interrupts conductive paths, promotes buoyancy- or wind-driven convection, and curtails radiative exchange. Key design parameters, including cavity depth, vent-area ratio, airflow velocity and surface emissivity, govern this balance, while hybrid ventilation offers the most excellent peak-load mitigation with modest energy input. A synthesis of simulation and field studies indicates that properly detailed VFs reduce envelope cooling loads by 20–55% across diverse climates and cut winter heating demand by 10–20% when vents are seasonally managed or coupled with heat-recovery devices. These thermal benefits translate into steadier interior surface temperatures, lower radiant asymmetry and fewer drafts, thereby expanding the hours occupants remain within comfort bands without mechanical conditioning. Climate-responsive guidance emerges in tropical and arid regions, favouring highly ventilated, low-absorptance cladding; temperate and continental zones gain from adaptive vents, movable insulation or PCM layers; multi-skin adaptive facades promise balanced year-round savings by re-configuring in real time. Overall, the review demonstrates that VFs constitute a versatile, passive-plus platform for low-carbon buildings, simultaneously enhancing energy efficiency, durability and indoor comfort. Future advances in smart controls, bio-based materials and integrated energy-recovery systems are poised to unlock further performance gains and accelerate the sector’s transition to net-zero. Emerging multifunctional materials such as phase-change composites, nanostructured coatings, and perovskite-integrated systems also show promise in enhancing facade adaptability and energy responsiveness. Full article
(This article belongs to the Special Issue Sustainable Development of Energy and Environment in Buildings)
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19 pages, 793 KiB  
Article
Lateral Asymmetries and Their Predictive Ability for Maximal Incremental Cycle Ergometer Performance in Road Cyclists
by Mario Iglesias-Caamaño, Jose Manuel Abalo-Rey, Tania Álvarez-Yates, Diego Fernández-Redondo, Jose Angel López-Campos, Fábio Yuzo Nakamura, Alba Cuba-Dorado and Oscar García-García
Symmetry 2025, 17(7), 1060; https://doi.org/10.3390/sym17071060 - 4 Jul 2025
Viewed by 421
Abstract
This study aimed to (1) determine and compare the magnitude and direction of asymmetry in lower limbs neuromuscular properties, range of motion, strength and muscle electrical activity (EMG) in well-trained male road cyclist across categories (elite, under-23 and junior); (2) establish test- and [...] Read more.
This study aimed to (1) determine and compare the magnitude and direction of asymmetry in lower limbs neuromuscular properties, range of motion, strength and muscle electrical activity (EMG) in well-trained male road cyclist across categories (elite, under-23 and junior); (2) establish test- and age-specific asymmetry thresholds for these variables to enable individualized classification; and (3) examine the relationship between these lateral asymmetries and performance in a maximal incremental cycle ergometer test. Fifty-five well-trained road cyclists were assessed through tensiomyography (TMG), active knee extension test (AKE), leg press and EMG of vastus lateralis (VL-EMG) during a maximal incremental cycling test. Junior cyclists showed lower asymmetry in VM than elite cyclists, but greater asymmetry in AKE. No significant differences were found in strength or VL-EMG during the maximal incremental cycle ergometer test. The magnitude and direction of lateral asymmetry differs between tests (TMG: 11.3–21.3%; AKE: 2.3%; leg-press: 9.8–31.9%; VL-EMG: 20.8–22.7%). Multiple linear regression revealed a significant predictive model for maximal incremental cycling ergometer performance based on lateral asymmetry in AKE, leg press and VL and rectus femoris contraction time (R2a = 0.23). These reference data can support trainers in monitoring and managing lateral asymmetry throughout the cyclists’ season. Full article
(This article belongs to the Section Life Sciences)
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13 pages, 1995 KiB  
Article
Topographic Control of Wind- and Thermally Induced Circulation in an Enclosed Water Body
by Jinichi Koue
Geosciences 2025, 15(7), 244; https://doi.org/10.3390/geosciences15070244 - 30 Jun 2025
Viewed by 231
Abstract
The dynamics of large lake circulations are strongly modulated by wind forcing, thermal gradients, and shoreline topography, yet their integrated effects remain insufficiently quantified. To address this, numerical simulations were conducted in Lake Biwa to clarify the mechanisms underlying wind- and thermally driven [...] Read more.
The dynamics of large lake circulations are strongly modulated by wind forcing, thermal gradients, and shoreline topography, yet their integrated effects remain insufficiently quantified. To address this, numerical simulations were conducted in Lake Biwa to clarify the mechanisms underlying wind- and thermally driven gyres, with a focus on the influence of bathymetric asymmetry. In wind-driven cases, zonal and meridional wind stress gradients were imposed, revealing that cyclonic wind shear generated strong surface vorticity (up to 2.0 × 10−6 s−1) in regions with gently sloped shores, while steep slopes suppressed anticyclonic responses. Cyclonic forcing induced upwelling in the lake center, with baroclinic return flows stabilizing the vertical circulation structure. In windless thermal experiments, surface temperature gradients of ±2.5 °C were applied to simulate seasonal heating and cooling. Cyclonic circulation predominated in warm seasons due to convergence and heat accumulation along gently sloping shores, whereas winter cooling produced divergent flows and anticyclonic gyres. The southern and eastern lake margins, characterized by mild slopes, consistently enhanced convergence and vertical mixing, while steep western and northern slopes limited circulation intensity. These results demonstrate that shoreline slope asymmetry plays a decisive role in regulating both wind- and thermally induced circulations, offering insights into physical controls on transport and stratification in enclosed lake systems. Full article
(This article belongs to the Section Climate and Environment)
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23 pages, 2098 KiB  
Article
Modeling Time Series with SARIMAX and Skew-Normal and Zero-Inflated Skew-Normal Errors
by M. Alejandro Dinamarca, Fernando Rojas, Claudia Ibacache-Quiroga and Karoll González-Pizarro
Mathematics 2025, 13(11), 1892; https://doi.org/10.3390/math13111892 - 5 Jun 2025
Viewed by 660
Abstract
This study proposes an extension of Seasonal Autoregressive Integrated Moving Average models with exogenous regressors (SARIMAX) by incorporating skew-normal and zero-inflated skew-normal error structures to better accommodate asymmetry and excess zeros in time series data. The proposed framework demonstrates improved flexibility and robustness [...] Read more.
This study proposes an extension of Seasonal Autoregressive Integrated Moving Average models with exogenous regressors (SARIMAX) by incorporating skew-normal and zero-inflated skew-normal error structures to better accommodate asymmetry and excess zeros in time series data. The proposed framework demonstrates improved flexibility and robustness compared to traditional Gaussian-based models. Simulation experiments reveal that the skewness parameter significantly affect forecasting accuracy, with reductions in mean absolute error (MAE) and root mean square error (RMSE) observed across both positively and negatively skewed scenarios. Notably, in negative-skew contexts, the model achieved an MAE of 0.40 and RMSE of 0.49, outperforming its symmetric-error counterparts. The inclusion of zero-inflation probabilities further enhances model performance in sparse datasets, yielding superior values in goodness-of-fit criteria such as the Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC). To illustrate the practical value of the methodology, a real-world case study is presented involving the modeling of optical density (OD600) data from Escherichia coli during stationary-phase growth. A SARIMAX(1,1,1) model with skew-normal errors was fitted to 200 time-stamped absorbance measurements, revealing significant positive skewness in the residuals. Bootstrap-derived confidence intervals confirmed the significance of the estimated skewness parameter (α=14.033 with 95% CI [12.07, 15.99]). The model outperformed the classical ARIMA benchmark in capturing the asymmetry of the stochastic structure, underscoring its relevance for biological, environmental, and industrial applications in which non-Gaussian features are prevalent. Full article
(This article belongs to the Special Issue Applied Statistics in Management Sciences)
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19 pages, 11205 KiB  
Article
Effects of Monsoon Circulation on Bedload Transport in the Qiongzhou Strait and Adjacent Seas Based on SCHISM
by Yuxin Huang, Xiangbai Wu, Huan Mei, Shouxian Zhu, Changliang Tong and Xinyi La
J. Mar. Sci. Eng. 2025, 13(5), 854; https://doi.org/10.3390/jmse13050854 - 25 Apr 2025
Viewed by 491
Abstract
This study quantitatively investigates monsoon-driven bedload sediment transport mechanisms in the Qiongzhou Strait using the SCHISM model, revealing three key findings: (1) Monsoon seasonality governs net sediment flux through contrasting hydrodynamic regimes, with the winter monsoon establishing spatially coherent westward transport pathways, while [...] Read more.
This study quantitatively investigates monsoon-driven bedload sediment transport mechanisms in the Qiongzhou Strait using the SCHISM model, revealing three key findings: (1) Monsoon seasonality governs net sediment flux through contrasting hydrodynamic regimes, with the winter monsoon establishing spatially coherent westward transport pathways, while the summer monsoon induces counteracting flow patterns that suppress net transport. (2) Winter conditions exhibit opposing transport vectors between tidal and monsoon forcing at both strait entrances, with monsoon dominance at the western entrance contrasting tidal predominance in the eastern sector. (3) Summer monsoon–tide hydrodynamic decoupling results in transport magnitudes ≤ 10% of tidal-driven quantities across critical cross-sections. The research elucidates sediment budget partitioning mechanisms in monsoon-dominated shelf seas, particularly revealing a spatial reversal of dominant transport drivers between eastern and western gateways that mechanistically explains observed sedimentary architecture asymmetries. By innovatively quantifying spatiotemporal coupling effects of meteorological and tidal forcing, this work advances theoretical understanding of sediment flux allocation under monsoonal systems and provides scientific support for seabed resource management and geomorphological evolution predictions. Full article
(This article belongs to the Section Coastal Engineering)
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16 pages, 4198 KiB  
Article
Early- and Latewood vs. Stem Asymmetry: Which Is More Important for Dendrochemistry in Scots Pine?
by Vladimir L. Gavrikov, Alexey I. Fertikov, Ruslan A. Sharafutdinov and Eugene A. Vaganov
Forests 2025, 16(3), 493; https://doi.org/10.3390/f16030493 - 11 Mar 2025
Viewed by 492
Abstract
For dendrochemical research, it may be important to be aware of the effects of stem asymmetry and the intra-ring structure because these may introduce unwanted dispersion in the results. In dendrochemical studies, separate analysis of the elemental content of early- and latewood is [...] Read more.
For dendrochemical research, it may be important to be aware of the effects of stem asymmetry and the intra-ring structure because these may introduce unwanted dispersion in the results. In dendrochemical studies, separate analysis of the elemental content of early- and latewood is rare. Also, explanations of how the elemental content may relate to stem asymmetry originating from conditions at the edges of contrasting environments are largely lacking in these studies. The purpose of the current study was to estimate the impact of the seasonal tree ring structure and stem asymmetry on the distribution of elements in tree stems. The study population was a plantation of Scots pine (Pinus sylvestris L.) at an afforestation experiment area, with the sample trees being at the edge of the stand, causing strong crown asymmetry. Six pine trees were cored through the thickness from the maximal crown side (max-side) to the minimal crown side (min-side), and the cores were subsequently scanned through an Itrax Multiscanner unit. The count rates of aluminum (Al), silicon (Si), phosphorus (P), sulfur (S), chlorine (Cl), calcium (Ca), iron (Fe), copper (Cu), zinc (Zn), and strontium (Sr) in the tree rings from 1990 to 2022 were analyzed. A group of elements (Al, Si, P, S, and Cl) tended to consistently concentrate on the min-side, both in early- and latewood, the difference being most significant for S and Cl. Regarding early- vs. latewood, Al, Si, P, S, Cl, Cu, and Zn always had lower concentration in earlywood than in latewood, while others (Ca, Fe, and Sr) had lower concentrations in latewood, the relations being consistently significant. Overall, the role of the min- or max-side of the stem in allocation of elements appears to have been weaker that the intra-ring structure (early- and latewood). Some elements such as Al, Si, P, S, Cl, and Ca (in latewood) were often more abundant on the min-side; other elements such as Fe and Sr (in latewood) were often more abundant on the max-side, but these relations were significant only on rare occasions. Intra-ring heterogeneity (in early- and latewood) appears to be more decisive than the asymmetry of the tree stem in regard to the distribution of elements in Scots pine xylem. Nevertheless, tree stems with high and obvious asymmetry should be more extensively explored because a possibility remains that extreme asymmetry does impact the allocation of elements. Full article
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14 pages, 2812 KiB  
Article
Leaf Traits and Fluctuating Asymmetry as Stress Indicators in a Mangrove Species After an Extreme Rainfall Event
by Dalton Serafim, Luziene Seixas, João Victor Sabino, Kim Ribeiro Barão, Jean Carlos Santos and Guilherme Ramos Demetrio
Stresses 2025, 5(1), 21; https://doi.org/10.3390/stresses5010021 - 3 Mar 2025
Viewed by 1156
Abstract
Climate change, particularly extreme rainfall, imposes stress on plants, which can be assessed using fluctuating asymmetry (FA) in leaves and key leaf traits. FA, which is defined as random deviations in symmetrical structures, is a known bioindicator of environmental stress. Additionally, leaf area [...] Read more.
Climate change, particularly extreme rainfall, imposes stress on plants, which can be assessed using fluctuating asymmetry (FA) in leaves and key leaf traits. FA, which is defined as random deviations in symmetrical structures, is a known bioindicator of environmental stress. Additionally, leaf area (LA) and specific leaf area (SLA) provide insights into plant responses to stressors. Mangrove plants have several mechanisms to cope with constant flooding and rainy periods. However, under extreme rainfall conditions, their adaptive capacity may be overwhelmed and plants may experience developmental stress. Nonetheless, it has not yet been verified whether plants subjected to drastic increases in rainfall exhibit more asymmetric leaves. We investigated seasonal differences in FA in Laguncularia racemosa after an extreme rainfall event and found a significant increase in FA after the rainfall event (t = 1.759, df = 149, p = 0.08) compared with the dry season. Concurrently, LA increased by 28% (p < 0.01) and SLA increased by 33% (p < 0.01) after the rainfall event. During the dry season, the plants exhibited antisymmetry rather than FA, highlighting their distinct responses to seasonal stressors. These findings demonstrate the differential effects of rainfall extremes on leaf traits and asymmetry, positioning FA, LA, and SLA as mangrove stress indicators. Full article
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11 pages, 716 KiB  
Article
Knee Mechanics, Strength and Flexibility: Assessing Injury Risk in Female Adolescent Soccer Players
by Koulla Parpa and Marcos Michaelides
J. Funct. Morphol. Kinesiol. 2025, 10(1), 77; https://doi.org/10.3390/jfmk10010077 - 25 Feb 2025
Viewed by 915
Abstract
Background/Objectives: This study examined the link between the Q angle, knee hyperextension, flexibility, strength profiles and injury occurrence in female adolescent soccer players. Methods: Thirty adolescent female soccer players (age range: 15–17 years; age: 15.47 ± 0.73 years; weight: 55.91 ± 7.44 kg; [...] Read more.
Background/Objectives: This study examined the link between the Q angle, knee hyperextension, flexibility, strength profiles and injury occurrence in female adolescent soccer players. Methods: Thirty adolescent female soccer players (age range: 15–17 years; age: 15.47 ± 0.73 years; weight: 55.91 ± 7.44 kg; height: 160.01 ± 5.58 cm) were recruited for the study. The tests were conducted before the pre-season preparation period, and the players were monitored from the beginning to the end of the season. This study included players who sustained non-contact injuries throughout the season as well as those who did not sustain any injuries for comparison purposes. Players underwent an anthropometric assessment (height, weight, body fat, Q angle, knee hyperextension) and completed a sit-and-reach test and an isokinetic assessment at 60°/s. Results: The results showed that 36.67% of players sustained a non-contact injury during the season. Based on the isokinetic assessment at 60°/s, significant differences were observed between the two groups in the torque production of the right and left knee extensors [t(28) = 2.32, p = 0.03, d = 0.81 (large effect)] and the right and left knee flexors [t(28) = 2.04, p = 0.05, d = 0.71 (medium effect)], with the injured group demonstrating significantly greater interlimb asymmetries in torque between the right and left knee extensors, as well as the right and left knee flexors. Also, the injured group demonstrated significantly higher knee hyperextension values for both the right [t(28) = 6.12, p < 0.05, d = 2.22 (large effect)] and left legs [t(28) = 5.72, p < 0.05, d = 2.15 (large effect)]. Conclusions: interlimb asymmetries and knee hyperextension may contribute to the occurrence of lower body non-contact injuries in adolescent female soccer players. Full article
(This article belongs to the Section Kinesiology and Biomechanics)
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22 pages, 2072 KiB  
Article
Clinical Assessment of Dairy Goats’ Udder Health Using Infrared Thermography
by Vera Korelidou, Zeljana Grbovic, Dejan Pavlovic, Isidora Simovic, Marko Panic, Anastasios Temenos and Athanasios I. Gelasakis
Animals 2025, 15(5), 658; https://doi.org/10.3390/ani15050658 - 24 Feb 2025
Cited by 2 | Viewed by 1458
Abstract
This study aimed to evaluate the capacity of infrared thermography (IRT) to be used for the in situ clinical assessment of udder health status across lactation in goats. Two epidemiological studies were designed, with 106 purebred Skopelos goats being prospectively monitored over one [...] Read more.
This study aimed to evaluate the capacity of infrared thermography (IRT) to be used for the in situ clinical assessment of udder health status across lactation in goats. Two epidemiological studies were designed, with 106 purebred Skopelos goats being prospectively monitored over one lactation in the first study and 132 goats of the same breed from a second farm being enrolled in the second, cross-sectional study. Goats were categorized based on the clinical status of each udder half (healthy, fibrotic, both fibrotic and asymmetric, asymmetric, swollen supra-mammary lymph nodes, and abscessed). Skin surface temperature values of teats (TSST) and udder halves (USST), as well as temperature variations between different types of abscesses, based on the stage of their development (superficial developed, superficial fully mature, drained), and the symmetrical sites of the non-affected udder halves, were evaluated. Mixed linear regression analyses indicated that fibrosis, particularly when accompanied by asymmetry, resulted in a decrease of 0.2, 0.3, and 0.3 °C (p < 0.05) and of 0.6, 0.9, and 1.4 °C (p < 0.001) in the maximum, mean, and minimum USST, respectively. Recording season significantly affected USST and TSST (p < 0.001), with both of them increasing between February and August. Additionally, TSST appeared to be an unreliable indicator of udder health status, while abscesses exhibited distinct temperature patterns based on their developmental stage. It is concluded that IRT has the potential to be used on site for the detection of temperature alterations associated with chronic udder health issues, yet future studies on a larger and more diverse population of goats with various udder health conditions is needed to confirm its extensive applicability under real-world conditions. Full article
(This article belongs to the Special Issue Ruminant Health: Management, Challenges, and Veterinary Solutions)
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14 pages, 6858 KiB  
Technical Note
Asymmetric Distribution of Plasma Blobs During High Solar Activity in the Low- to Middle-Latitude Ionosphere
by Zhuo Huang, Jia Zhu, Weihua Luo, Zhengping Zhu, Guodong Jia and Shanshan Chang
Remote Sens. 2025, 17(1), 82; https://doi.org/10.3390/rs17010082 - 28 Dec 2024
Viewed by 704
Abstract
Using the data from the first satellite of the Republic of China (ROCSAT-1) obtained during high-solar-activity periods (2000–2003), the distributions of plasma density enhancement (plasma blobs) with local time, season and longitude were investigated. Some new features of plasma blobs can be concluded: [...] Read more.
Using the data from the first satellite of the Republic of China (ROCSAT-1) obtained during high-solar-activity periods (2000–2003), the distributions of plasma density enhancement (plasma blobs) with local time, season and longitude were investigated. Some new features of plasma blobs can be concluded: (a) The distribution of plasma blobs shows remarkable seasonal and interhemispheric asymmetries, with the higher occurrence in June solstice months and in the winter hemisphere. (b) The occurrence of plasma blobs displays longitude dependence, more in the −180~−90°E, −60~0°E and 90~180°E longitude regions. (c) The seasonal and interhemispheric asymmetries of plasma blobs also depend on the longitude. Meridional wind plays an important role in the formation and evolution of low-latitude plasma blobs. Inclination and declination may control the longitudinal distribution of plasma blobs. Full article
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15 pages, 2567 KiB  
Article
Wild Bee Diversity and Bee–Plant Interactions in Tropical and Temperate Forest Clearings in a Natural Protected Area in Central West Mexico
by Alvaro Edwin Razo-León, Alejandro Muñoz-Urias, Claudia Aurora Uribe-Mú, Francisco Martín Huerta-Martínez, Hugo Eduardo Fierros-López, Miguel Vásquez-Bolaños, Gustavo Moya-Raygoza and Pablo Carrillo-Reyes
Insects 2024, 15(12), 1009; https://doi.org/10.3390/insects15121009 - 20 Dec 2024
Viewed by 1326
Abstract
Background: Bees rely on plants for nutrition and reproduction, making the preservation of natural areas crucial as pollinator reservoirs. Seasonal tropical dry forests are among the richest habitats for bees, but only 27% of their original extent remains in Mexico. In contrast, temperate [...] Read more.
Background: Bees rely on plants for nutrition and reproduction, making the preservation of natural areas crucial as pollinator reservoirs. Seasonal tropical dry forests are among the richest habitats for bees, but only 27% of their original extent remains in Mexico. In contrast, temperate forests harbor fewer bee species and face high deforestation rates, with 40% of their area converted to other land uses. This study aimed to estimate the α and β diversities of wild bees and compare bee–plant interaction networks between these two vegetation types. Methods: Wild bees and their interactions with plants were monitored for one year in four sites within the Área de Protección de Flora y Fauna Sierra de Quila. Two sites corresponded to seasonal tropical dry forest and two to temperate forest. α and β diversity, connectance, nestedness, web asymmetry, and niche overlap were analyzed. Results: Sierra de Quila harbors high bee diversity, with 155 species in tropical dry forest and 103 in temperate forest. Species turnover between vegetation types was high, although nine species used floral resources in both forests, connecting the interaction networks. Conclusions: Sierra de Quila diverse habitats promote high bee diversity, with niche partitioning and low connectance facilitating coexistence across different vegetation types. Full article
(This article belongs to the Section Social Insects and Apiculture)
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20 pages, 8224 KiB  
Article
Statistical Analysis of the Occurrence of Ionospheric Scintillations at the Low-Latitude Sanya Station During 2004–2021
by Bo Xiong, Changhao Yu, Xiaolin Li, Yuxiao Li, Lianhuan Hu, Yuqing Wang, Lingxiao Du and Yuxin Wang
Remote Sens. 2024, 16(24), 4668; https://doi.org/10.3390/rs16244668 - 13 Dec 2024
Viewed by 934
Abstract
The ionosphere of the Earth often becomes turbulent and develops electron density irregularities that can cause rapid and random changes in the amplitude and phase of radio signals, which is known as ionospheric scintillation. In this study, the statistical behavior of global navigation [...] Read more.
The ionosphere of the Earth often becomes turbulent and develops electron density irregularities that can cause rapid and random changes in the amplitude and phase of radio signals, which is known as ionospheric scintillation. In this study, the statistical behavior of global navigation satellite system (GNSS) ionospheric amplitude scintillation of varying intensities over the Chinese low-latitude station in Sanya (18.34°N, 109.62°E; magnetic latitude: 7.61°N) has been investigated with respect to its dependence on solar activity, seasons, local time (LT), and geomagnetic activity during the period from July 2004 to December 2021. A detailed study on the solar activity dependence of scintillation occurrence shows that the occurrence rates of strong and moderate scintillations significantly increase with enhanced solar activity, but weak amplitude scintillations do not entirely conform to this characteristic. In terms of seasonal dependence, the scintillations in Sanya from 2004 to 2021 mainly occurred during equinoxes and exhibit a distinct equinoctial asymmetry. This asymmetry is characterized by a higher occurrence rate in autumn than in spring during the years 2007, 2011, and from 2017 to 2021, while in other years, the pattern is reversed, with a higher occurrence rate in spring than in autumn. Regarding LT dependence, scintillations are predominantly observed during 19:30–23:30 LT, with a notable persistence beyond midnight during years of high solar activity. Furthermore, geomagnetic disturbances have been observed to promote weak scintillations at 20:00 LT during the autumn and winter of 2014, and from 20:00 LT to 01:00 LT the next day in the latter half of 2013. In contrast, during the spring and autumn of most other years with high solar activity, these disturbances have been found to inhibit weak scintillations from 20:00 LT to midnight. The promoting/inhibiting effect of geomagnetic disturbances on ionospheric scintillation is not solely influenced by electric field disturbances but is to some extent jointly controlled by a variety of factors including solar activity, season, and LT. Full article
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20 pages, 10219 KiB  
Article
Climatology of Polar Stratospheric Clouds Derived from CALIPSO and SLIMCAT
by Douwang Li, Zhe Wang, Shun Li, Jiankai Zhang and Wuhu Feng
Remote Sens. 2024, 16(17), 3285; https://doi.org/10.3390/rs16173285 - 4 Sep 2024
Cited by 1 | Viewed by 1340
Abstract
Polar stratospheric clouds (PSCs) play a crucial role in ozone depletion in the polar stratosphere. In this study, the space-based PSCs record from CALISPO and an offline three-dimensional chemical transport model (SLIMCAT) are used to analyze the PSCs in the Arctic and the [...] Read more.
Polar stratospheric clouds (PSCs) play a crucial role in ozone depletion in the polar stratosphere. In this study, the space-based PSCs record from CALISPO and an offline three-dimensional chemical transport model (SLIMCAT) are used to analyze the PSCs in the Arctic and the Antarctic for the period 2006−2021. Observations indicate that the seasonal evolution of the Antarctic PSC area is similar from year to year. In contrast, the Arctic PSCs show large differences in seasonal variations of coverage and duration in different years. The SLIMCAT simulations effectively capture the seasonal and interannual variations of PSCs. However, the simulated PSC areas are larger than CALIPSO observations, which can be attributed to the relatively high instrumental detection threshold of CALIPSO. SLIMCAT can capture the zonal asymmetry of PSCs in both the Antarctic and Arctic, and it can reproduce a more accurate spatial distribution of PSCs when the PSC coverage area is larger. In addition, accurate simulation of HNO3 is important for PSC simulation. Because the simulation of denitrification processes is poor in SLIMCAT, which uses the thermodynamic equilibrium PSC scheme, the PSCs modeled by SLIMCAT are located at higher altitudes compared to the observation in the Antarctic, where the denitrification processes are strong. In contrast, for ice PSCs of which HNO3 is not required in calculations and the Arctic where denitrification is weak, the simulated PSC at different altitudes closely matches the observations. Full article
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23 pages, 4832 KiB  
Article
Influence of Short-Term Variations in Solar Activity on Total Electron Content
by Plamen Mukhtarov and Rumiana Bojilova
Atmosphere 2024, 15(8), 913; https://doi.org/10.3390/atmos15080913 - 30 Jul 2024
Viewed by 948
Abstract
In the present work, the variations in Total Electron Content (TEC) induced by changes in the ionizing radiation of the Sun, which are related to the rotation period (about 27 days), were investigated. This study was based on a 30-year period. The relative [...] Read more.
In the present work, the variations in Total Electron Content (TEC) induced by changes in the ionizing radiation of the Sun, which are related to the rotation period (about 27 days), were investigated. This study was based on a 30-year period. The relative deviations in the TEC and F10.7 values were used in the data analysis. The use of this modification aimed to eliminate the stationary diurnal, seasonal, and solar course of the TEC over the course of the long-term variations in solar activity, preserving the variations within a time scale of 27 days and less. As a result, the values of the linear regression coefficient between the relative deviations in the two considered quantities from the median (quiet conditions) for one rotation period were obtained. Depending on the general level of solar activity, the season, and the latitude, this coefficient varied between 40% and 60%. The analysis showed that the minimum values were observed during high solar activity. The latitudinal distribution demonstrated an increase in the area of the Equatorial Ionization Anomaly (EIA) under the influence of the so-called “fountain effect”. As a result, there was a seasonal variation and an increase in the winter months at mid and high latitudes and a decrease in the months of the minimum zenith angle of the Sun at low latitudes. A well-pronounced asymmetry in the equinox months was also obtained. The obtained results are the novelty of this study and can be used to improve empirical models for short-term TEC forecasting. Full article
(This article belongs to the Section Upper Atmosphere)
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12 pages, 2669 KiB  
Article
Evaluation of Lower Limb Asymmetry Index Based on the 30-Second Skater Squat Functional Test in Young Men
by Mateusz Kamiński and Anna Katarzyna Cygańska
J. Clin. Med. 2024, 13(14), 4017; https://doi.org/10.3390/jcm13144017 - 10 Jul 2024
Viewed by 2375
Abstract
Introduction: Physical performance tests (PPTs) are used for the pre-season evaluation of athletes and to monitor and control the rehabilitation process. PPTs include single-leg jumps, single-leg squats, and balance tests. One of the physical fitness tests is the skater squat test. The 30 [...] Read more.
Introduction: Physical performance tests (PPTs) are used for the pre-season evaluation of athletes and to monitor and control the rehabilitation process. PPTs include single-leg jumps, single-leg squats, and balance tests. One of the physical fitness tests is the skater squat test. The 30 s skater squat functional test (SSFT) is used as one of the tests to assess fitness and symmetry in the lower limbs. The present study aimed to calculate and compare the asymmetry index using the 30 s skater squat functional test, the single-leg distance jump test, and the isometric measurement of knee joint extensor strength. Materials and Methods: The study examined 25 men aged 23 ± 3.17 years. The study used the 30 s SSFT, the single-leg long jump test (SLLJT), and an isometric dynamometer test to measure peak moment of force values for extensors of the knee using the JBA Zbigniew Staniak® measuring station (“JBA” Zb. Staniak, Poland). The statistical analysis of functional test results and iso-metric dynamometry results was based on correlation analysis. Results: There was a moderate correlation between 30 s SSFT and SLLJT (r = 0.540), and between SLLJT and measurements of peak moment of force of the knee joint extensors (r = 0.533). Conclusions: The asymmetry index calculated based on functional tests and peak moment of force of the knee extensors in a group of young men should not be used interchangeably. The asymmetry index calculated from the 30 s skater squat functional test detects greater differences in knee extensor strength than the ASI index calculated from the single-leg long jump test in a group of young male athletes. The practical significance of this study was that its results could play an important role in the training process and monitoring the return to sports after a possible injury. Full article
(This article belongs to the Section Sports Medicine)
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