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10 pages, 485 KiB  
Article
Factors Associated with Functional Outcome Following Acute Ischemic Stroke Due to M1 MCA/ICA Occlusion in the Extended Time Window
by John Constantakis, Quinn Steiner, Thomas Reher, Timothy Choi, Fauzia Hollnagel, Qianqian Zhao, Nicole Bennett, Veena A. Nair, Eric E. Adelman, Vivek Prabhakaran, Beverly Aagard-Kienitz and Bolanle Famakin
J. Clin. Med. 2025, 14(15), 5556; https://doi.org/10.3390/jcm14155556 - 6 Aug 2025
Abstract
Introduction: A validated clinical decision tool predictive of favorable functional outcomes following endovascular thrombectomy (EVT) in acute ischemic stroke (AIS) remains elusive. We performed a retrospective case series of patients at our regional Comprehensive Stroke Center, over a four-year period, who have undergone [...] Read more.
Introduction: A validated clinical decision tool predictive of favorable functional outcomes following endovascular thrombectomy (EVT) in acute ischemic stroke (AIS) remains elusive. We performed a retrospective case series of patients at our regional Comprehensive Stroke Center, over a four-year period, who have undergone EVT to elucidate patient characteristics and factors associated with a favorable functional outcome after EVT. Methods: We reviewed all cases of EVT at our institution between February 2018 and February 2022 in the extended time window from 6–24 h. Demographic, clinical, imaging, and procedure co-variates were included. A favorable clinical outcome was defined as a modified Rankin scale of 0–2. We included patients with M1 or internal carotid artery occlusion treated with EVT within 6–24 h after symptom onset. We used a univariate and multivariate logistic regression analysis to identify patient factors associated with a favorable clinical outcome at 90 days. Results: Our study included evaluation of 121 patients who underwent EVT at our comprehensive stroke center. Our analysis demonstrates that a higher recanalization score based on the modified Thrombolysis In Cerebral Infarction (mTICI) scale (2B-3) was a strong indicator of a favorable outcome (OR 7.33; CI 2.06–26.07; p = 0.0021). Our data also showed that a higher baseline National Institutes of Health Stroke Scale (NIHSS) score (p = 0.0095) and the presence of pre-existing hypertension (p = 0.0035) may also be predictors of an unfavorable outcome (mRS > 2) per our multivariate analysis. Conclusion: Patients without pre-existing hypertension had more favorable outcomes following EVT in the expanded time window. This is consistent with other multicenter data in the expanded time window that demonstrates greater odds of a poor outcome with elevated pre-, peri-, and post-endovascular-treatment blood pressure. Our data also demonstrate that the mTICI score is a strong predictor of favorable outcome, even after controlling for other variables. A lower baseline NIHSS at the time of thrombectomy may also indicate a favorable outcome. Furthermore, the presence of clinical or radiographic mismatch based on the Alberta Stroke Program Early Computed Tomography Score (ASPECTS) and NIHSS per DAWN and DEFUSE-3 criteria did not emerge as a predictor of favorable outcome, which is congruent with recent randomized controlled trials and meta-analyses. Full article
(This article belongs to the Special Issue Ischemic Stroke: Diagnosis and Treatment)
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11 pages, 533 KiB  
Article
Paired-Pulse Repetitive Trans-Spinal Magnetic Stimulation Supports Balance Ability While the Coil Orientation Significantly Determines the Effects: A Randomised, Placebo-Controlled Trial
by Jitka Veldema, Michel Klemm, Jan Straub, Saskia Kurtzhals, Lea Sasse and Teni Steingräber
Biomedicines 2025, 13(8), 1920; https://doi.org/10.3390/biomedicines13081920 - 6 Aug 2025
Abstract
Objectives: The primary objective was to investigate and compare the effects of three paired-pulse repetitive trans-spinal magnetic stimulation (PP-rTSMS) protocols on balance control and corticospinal network function. Methods: PP-rTSMS (800 pulses, frequency 100 Hz, intensity 70% of the resting motor threshold) was [...] Read more.
Objectives: The primary objective was to investigate and compare the effects of three paired-pulse repetitive trans-spinal magnetic stimulation (PP-rTSMS) protocols on balance control and corticospinal network function. Methods: PP-rTSMS (800 pulses, frequency 100 Hz, intensity 70% of the resting motor threshold) was applied over the eighth thoracic vertebra (Th8) in twenty-seven young healthy individuals. Each proband received three verum sessions (using a verum coil with handle oriented (i) cranially, (ii) caudally, and (iii) laterally) and (iv) one sham session (using a sham coil) in a randomised order. Balance ability (Y Balance Test) and corticospinal network functions (motor evoked potentials (MEPs), cortical silent periods (SCPs)) were tested immediately (i) prior to and (ii) after each interventional session. Results: Each verum session induced a significant improvement in balance ability (cranially (F1,26 = 8.009; p = 0.009; η2 = 0.236), caudally (F1,26 = 4.846; p = 0.037; η2 = 0.157), and laterally (F1,26 = 23,804; p ≤ 0.001; η2 = 0.478) oriented grip) as compared to the sham session. In addition, the laterally oriented coil grip was associated with significantly greater balance benefits than both the cranial (F1,26 = 10.173; p = 0.004; η2 = 0.281) and caudal (F1,26 = 14.058; p ≤ 0.001; η2 = 0.351) grip orientations. No significant intervention-induced effects were detected on corticospinal network functions. Conclusions: Our data show that PP-rTSMS effectively supports balance control and that coil orientation significantly influences these effects. Further studies should test variations of this promising approach on healthy and disabled cohorts. Full article
(This article belongs to the Section Molecular and Translational Medicine)
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19 pages, 790 KiB  
Article
How Does the Power Generation Mix Affect the Market Value of US Energy Companies?
by Silvia Bressan
J. Risk Financial Manag. 2025, 18(8), 437; https://doi.org/10.3390/jrfm18080437 - 6 Aug 2025
Abstract
To remain competitive in the decarbonization process of the economy worldwide, energy companies must preserve their market value to attract new investors and remain resilient throughout the transition to net zero. This article examines the market value of US energy companies during the [...] Read more.
To remain competitive in the decarbonization process of the economy worldwide, energy companies must preserve their market value to attract new investors and remain resilient throughout the transition to net zero. This article examines the market value of US energy companies during the period 2012–2024 in relation to their power generation mix. Panel regression analyses reveal that Tobin’s q and price-to-book ratios increase significantly for solar and wind power, while they experience moderate increases for natural gas power. In contrast, Tobin’s q and price-to-book ratios decline for nuclear and coal power. Furthermore, accounting-based profitability, measured by the return on assets (ROA), does not show significant variation with any type of power generation. The findings suggest that market investors prefer solar, wind, and natural gas power generation, thereby attributing greater value (that is, demanding lower risk compensation) to green companies compared to traditional ones. These insights provide guidance to executives, investors, and policy makers on how the power generation mix can influence strategic decisions in the energy sector. Full article
(This article belongs to the Special Issue Linkage Between Energy and Financial Markets)
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20 pages, 6555 KiB  
Article
Statistical Study of Whistler-Mode Waves in the Magnetospheric Magnetic Ducts
by Salman A. Nejad and Anatoly V. Streltsov
Universe 2025, 11(8), 260; https://doi.org/10.3390/universe11080260 - 6 Aug 2025
Abstract
This paper presents a comprehensive statistical analysis of extremely/very low-frequency (ELF/VLF) whistler-mode waves observed within magnetic ducts (B-ducts) using data from NASA’s Magnetospheric Multiscale (MMS) mission. A total of 687 events were analyzed, comprising 504 occurrences on the dawn-side flank of [...] Read more.
This paper presents a comprehensive statistical analysis of extremely/very low-frequency (ELF/VLF) whistler-mode waves observed within magnetic ducts (B-ducts) using data from NASA’s Magnetospheric Multiscale (MMS) mission. A total of 687 events were analyzed, comprising 504 occurrences on the dawn-side flank of the magnetosphere and 183 in the nightside magnetotail, to investigate the spatial distribution and underlying mechanisms of wave–particle interactions. We identify distinct differences between these regions by examining key parameters such as event width, frequency, plasma density, and magnetic field extrema within B-ducts. Using an independent two-sample t-test, we assess the statistical significance of variations in these parameters between different observation periods. This study provides valuable insights into the magnetospheric conditions influencing B-duct formation and wave propagation, offering a framework for understanding ELF/VLF wave dynamics in Earth’s space environment. Full article
(This article belongs to the Section Space Science)
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32 pages, 1320 KiB  
Systematic Review
Theory of Mind Development in Deaf and Hard-of-Hearing Individuals: A Systematic Review
by Leire Martín, Mario Figueroa, Beatriz de Diego-Lázaro, Raquel Balboa-Castells and Gary Morgan
Behav. Sci. 2025, 15(8), 1065; https://doi.org/10.3390/bs15081065 - 6 Aug 2025
Abstract
Theory of Mind (ToM) is a construct that includes a range of connected abilities linked to the understanding of others’ mental states. During the last three decades, ToM development has been studied extensively in deaf and hard of hearing (DHH) individuals and performances [...] Read more.
Theory of Mind (ToM) is a construct that includes a range of connected abilities linked to the understanding of others’ mental states. During the last three decades, ToM development has been studied extensively in deaf and hard of hearing (DHH) individuals and performances compared to the typically hearing (TH) population. Given the advances in the early diagnosis of deafness, interventions, and hearing devices over this period, variations in task performance among DHH participants might have been reduced. The current systematic review aims to synthesize all studies of ToM in DHH individuals and answer the following question: Do DHH individuals (Population), compared to a control sample of TH and/or among themselves (Comparator), in an assessment of ToM (Intervention), have differentiated results (Outcome)? After a search of the literature, 97 papers were included. We found that, in general, TH participants outperformed their DHH peers in ToM measures; however, there was a wide range of results. Explanations for this variability included the quality of early interactions and early exposure to both signed and spoken language. The review also indicates that the understanding of false belief was the most studied component within ToM, while other components, such as understanding intention and irony, require further research. Implications of these findings for clinical practice are discussed. Full article
(This article belongs to the Special Issue Language and Cognitive Development in Deaf Children)
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16 pages, 4615 KiB  
Article
Daily Variation in the Feeding Activity of Pacific Crown-of-Thorns Starfish (Acanthaster cf. solaris)
by Josie F. Chandler, Deborah Burn, Will F. Figueira, Peter C. Doll, Abby Johandes, Agustina Piccaluga and Morgan S. Pratchett
Biology 2025, 14(8), 1001; https://doi.org/10.3390/biology14081001 - 5 Aug 2025
Abstract
The ecological impact of crown-of-thorns starfish (CoTS; Acanthaster spp.) on coral reefs is intrinsically linked to their feeding behaviour. Management thresholds designed to mitigate coral loss driven by elevated densities of crown-of-thorns starfish rely on accurate estimates of individual feeding rates. In this [...] Read more.
The ecological impact of crown-of-thorns starfish (CoTS; Acanthaster spp.) on coral reefs is intrinsically linked to their feeding behaviour. Management thresholds designed to mitigate coral loss driven by elevated densities of crown-of-thorns starfish rely on accurate estimates of individual feeding rates. In this study, structure-from-motion photogrammetry and intensive tracking of adult Pacific CoTS over an extended survey period were used to generate three-dimensional, high-resolution estimates of daily feeding rates. Our findings revealed substantial variation in the areal extent of coral consumed, both across consecutive days and among individuals. Notably, CoTS did not feed consistently; feeding occurred on 65% of observation days, with 2–3 days periods of inactivity common. Despite this variability, mean daily feeding rates aligned with previous studies (1.35 coral colonies d−1; 198.4 cm2 day−1 planar area, and 998.83 cm2 day−1 three-dimensional surface area). Across all tracked individuals (n = 8), feeding was recorded on 17 coral genera; however, Acropora alone accounted for 51% of colonies consumed and contributed 82% of the total three-dimensional surface area ingested during the survey period. This highlights the disproportionately large feeding yield derived from Acropora-dominated diets and raises important questions about how future declines in Acropora cover may impact CoTS feeding success and energetic intake. Full article
(This article belongs to the Section Marine Biology)
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23 pages, 4325 KiB  
Article
Groundwater Level Estimation Using Improved Transformer Model: A Case Study of the Yellow River Basin
by Tianming Zhou, Chun Fu, Yezhong Liu and Libin Xiang
Water 2025, 17(15), 2318; https://doi.org/10.3390/w17152318 - 4 Aug 2025
Viewed by 199
Abstract
Accurate estimation of groundwater levels in river basins is essential for effective water resource planning. Innovations in deep learning and artificial intelligence (AI) have been introduced into this field to enhance the accuracy of long-term groundwater level estimation. This study employs the Transformer [...] Read more.
Accurate estimation of groundwater levels in river basins is essential for effective water resource planning. Innovations in deep learning and artificial intelligence (AI) have been introduced into this field to enhance the accuracy of long-term groundwater level estimation. This study employs the Transformer deep learning model to estimate groundwater levels, with a benchmark comparison against the long short-term memory (LSTM) model. These models were applied to estimate groundwater levels in the Yellow River Basin, where approximately 1100 monitoring wells are located. Monthly average groundwater level data from the period 2018–2023 were collected from these wells. The two models were used to estimate groundwater levels for the period 2003–2017 by incorporating remote sensing information. The Transformer model was enhanced to simultaneously capture features from both historical temporal data and surrounding spatial data, while automatically enhancing key features, effectively improving estimation accuracy and robustness. At the basin-averaged scale, the enhanced Transformer model outperformed the LSTM model: R2 increased by approximately 17.5%, while RMSE and MAE decreased by approximately 12.4% and 10.9%, respectively. The proportion of poorly predicted samples decreased by an average of approximately 12.1%. The estimation model established in this study contributes to improving the quantitative analysis capability of long-term groundwater level variations in the Yellow River Basin. This could be helpful for water resource development planning in this densely populated region and likely has broad applicability in other river basins. Full article
(This article belongs to the Special Issue Machine Learning Applications in the Water Domain)
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30 pages, 9610 KiB  
Article
Can the Building Make a Difference to User’s Health in Indoor Environments? The Influence of PM2.5 Vertical Distribution on the IAQ of a Student House over Two Periods in Milan in 2024
by Yong Yu, Marco Gola, Gaetano Settimo and Stefano Capolongo
Atmosphere 2025, 16(8), 936; https://doi.org/10.3390/atmos16080936 (registering DOI) - 4 Aug 2025
Viewed by 74
Abstract
This study investigates indoor and outdoor air quality monitoring in a student dormitory located in northern Milan (Italy) using low-cost sensors. This research compares two monitoring periods in June and October 2024 to examine common PM2.5 vertical patterns and differences at the [...] Read more.
This study investigates indoor and outdoor air quality monitoring in a student dormitory located in northern Milan (Italy) using low-cost sensors. This research compares two monitoring periods in June and October 2024 to examine common PM2.5 vertical patterns and differences at the building level, as well as their influence on the indoor spaces at the corresponding positions. In each period, around 30 sensors were installed at various heights and orientations across indoor and outdoor spots for 2 weeks to capture spatial variations around the building. Meanwhile, qualitative surveys on occupation presence, satisfaction, and well-being were distributed in selected rooms. The analysis of PM2.5 data reveals that the building’s lower floors tended to have slightly higher outdoor PM2.5 concentrations, while the upper floors generally had lower PM2.5 indoor/outdoor (I/O) ratios, with the top-floor rooms often below 1. High outdoor humidity reduced PM infiltration, but when outdoor PM fell below 20 µg/m3 in these two periods, indoor sources became dominant, especially on the lower floors. Air pressure I/O differences had minimal impact on PM2.5 I/O ratios, though slightly positive indoor pressure might help prevent indoor PM infiltration. Lower ventilation in Period-2 possibly contributed to more reported symptoms, especially in rooms with higher PM from shared kitchens. While outdoor air quality affects IAQ, occupant behavior—especially window opening and ventilation management—remains crucial in minimizing indoor pollutants. Users can also manage exposure by ventilating at night based on comfort and avoiding periods of high outdoor PM. Full article
(This article belongs to the Special Issue Air Quality in Metropolitan Areas and Megacities (Second Edition))
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16 pages, 3138 KiB  
Article
Seasonal and Interannual Variations (2019–2023) in the Zooplankton Community and Its Size Composition in Funka Bay, Southwestern Hokkaido
by Haochen Zhang, Atsushi Ooki, Tetsuya Takatsu and Atsushi Yamaguchi
Oceans 2025, 6(3), 49; https://doi.org/10.3390/oceans6030049 - 4 Aug 2025
Viewed by 58
Abstract
Funka Bay, located in southwest Hokkaido, is a vital fishing area with a shallow depth of less than 100 m. Seasonal flows of the Oyashio and Tsugaru Warm Current affect the marine environment, leading to significant changes in zooplankton communities, yet limited information [...] Read more.
Funka Bay, located in southwest Hokkaido, is a vital fishing area with a shallow depth of less than 100 m. Seasonal flows of the Oyashio and Tsugaru Warm Current affect the marine environment, leading to significant changes in zooplankton communities, yet limited information is available on these variations. This study used ZooScan imaging to analyze seasonal and interannual changes in zooplankton abundance, biovolume, community structure, and size composition from 2019 to 2023. Water temperature was low in March–April and high in September–November, with chlorophyll a peaks occurring from February to April. Notable taxa such as Thaliacea, Noctiluca, and cladocerans were more common in the latter half of the year. Interannual variations included a decline in large cold-water copepods, Eucalanus bungii and Neocalanus spp., which were abundant in 2019 but decreased by 2023. Zooplankton abundance and biovolume showed synchronized seasonal changes, correlating with shifts in the Normalized Biovolume Size Spectra (NBSS) index, which measures size composition. Cluster analysis identified eight zooplankton communities, with Community A dominant from July to December across all years, while Community D was prevalent in early 2019 but was replaced in subsequent years. Community E emerged from March to April in 2021–2023. In 2019, large cold-water copepods were dominant, but from 2020 to 2023, appendicularians became the dominant group during the March–April period. The decline in large copepods is likely linked to marine heat waves, influencing yearly zooplankton community changes. Full article
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21 pages, 7111 KiB  
Article
Seasonal Variation in Energy Balance, Evapotranspiration and Net Ecosystem Production in a Desert Ecosystem of Dengkou, Inner Mongolia, China
by Muhammad Zain Ul Abidin, Huijie Xiao, Sanaullah Magsi, Fang Hongxin, Komal Muskan, Phuocthoi Hoang and Muhammad Azher Hassan
Water 2025, 17(15), 2307; https://doi.org/10.3390/w17152307 - 3 Aug 2025
Viewed by 261
Abstract
This study investigates the seasonal dynamics of energy balance, evapotranspiration (ET), and Net Ecosystem Production (NEP) in the Dengkou desert ecosystem of Inner Mongolia, China. Using eddy covariance and meteorological data from 2019 to 2022, the research focuses on understanding how these processes [...] Read more.
This study investigates the seasonal dynamics of energy balance, evapotranspiration (ET), and Net Ecosystem Production (NEP) in the Dengkou desert ecosystem of Inner Mongolia, China. Using eddy covariance and meteorological data from 2019 to 2022, the research focuses on understanding how these processes interact in one of the world’s most water-limited environments. This arid research area received an average of 109.35 mm per annum precipitation over the studied period, classifying the region as a typical arid ecosystem. Seasonal patterns were observed in daily air temperature, with extremes ranging from −20.6 °C to 29.6 °C. Temporal variations in sensible heat flux (H), latent heat flux (LE), and net radiation (Rn) peaked during summer season. The average ground heat flux (G) was mostly positive throughout the observation period, indicating heat transmission from atmosphere to soil, but showed negative values during the winter season. The energy balance ratio for the studied period was in the range of 0.61 to 0.80, indicating challenges in achieving energy closure and ecological shifts. ET exhibited two annual peaks influenced by vegetation growth and climate change, with annual ET exceeding annual precipitation, except in 2021. Net ecosystem production (NEP) from 2019 to 2020 revealed that the Dengkou desert were a net source of carbon, indicating the carbon loss from the ecosystem. In 2021, the Dengkou ecosystem shifted to become a net carbon sink, effectively sequestrating carbon. However, this was sharply reversed in 2022, resulting in a significant net release of carbon. The study findings highlight the complex interactions between energy balance components, ET, and NEP in desert ecosystems, providing insights into sustainable water management and carbon neutrality strategies in arid regions under climate change effect. Full article
(This article belongs to the Special Issue The Observation and Modeling of Surface Air Hydrological Factors)
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16 pages, 5845 KiB  
Article
Ultrastructure and Transcriptomic Analysis Reveal Alternative Pathways of Zona Radiata Formation in Culter alburnus with Different Spawning Habits
by Yan Zhao, Ge Xue, Yanghui Peng, Jia Zhang, Feng Chen, Yeke Wang, Jun He, Jun Chen and Ping Xie
Biology 2025, 14(8), 987; https://doi.org/10.3390/biology14080987 (registering DOI) - 3 Aug 2025
Viewed by 198
Abstract
Spawning diversity plays an essential role in fish survival and reproduction, which contributes to the exceptional diversity of teleosts among vertebrates. Different zona radiata structures reflect the adaptability of fish to the environment of spawning and early embryonic development. The morphological and transcriptional [...] Read more.
Spawning diversity plays an essential role in fish survival and reproduction, which contributes to the exceptional diversity of teleosts among vertebrates. Different zona radiata structures reflect the adaptability of fish to the environment of spawning and early embryonic development. The morphological and transcriptional characteristics of fish follicle development between different spawning habits, particularly the zona radiata variations, have been poorly documented. In this study, we integrated histology and transcriptomics to investigate the differences in the zona radiata structure and gene expression profiles among follicles from different spawning habits of Culter alburnus. Our results revealed that stage Ⅲ was the crucial period for zona radiata thickening and structure differentiation. Transcriptomic analyses of adhesive and semi-buoyant eggs at stage Ⅲ revealed a significant upregulation of genes involved in glycoprotein synthesis, extracellular matrix formation, and regulation of protease activity in adhesive eggs, such as the wfdc and a2ml gene family. This upregulation likely underpins the thicker zona radiata in adhesive eggs, facilitating their attachment to substrates. This study represents the first elucidation of the ultrastructure of the zona radiata and gene expression patterns in different developmental stages of adhesive and semi-buoyant eggs of Culter alburnus, offering new perspectives for aquaculture research in understanding fish reproductive adaptations. Full article
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16 pages, 1795 KiB  
Article
Assessing and Improving the Reproducibility of Cerebrovascular Reactivity Evaluations in Healthy Subjects Using Short-Breath-Hold fMRI
by Emely Renger, Till-Karsten Hauser, Uwe Klose, Ulrike Ernemann and Leonie Zerweck
Diagnostics 2025, 15(15), 1946; https://doi.org/10.3390/diagnostics15151946 - 3 Aug 2025
Viewed by 252
Abstract
Background/Objectives: Cerebrovascular reactivity (CVR) is a key marker of cerebrovascular function, facilitating the early detection of neurovascular dysfunction. Breath-hold functional MRI (bh-fMRI) is a non-invasive method for assessing CVR. This study evaluates the reproducibility of bh-fMRI using short breath-hold periods, which are [...] Read more.
Background/Objectives: Cerebrovascular reactivity (CVR) is a key marker of cerebrovascular function, facilitating the early detection of neurovascular dysfunction. Breath-hold functional MRI (bh-fMRI) is a non-invasive method for assessing CVR. This study evaluates the reproducibility of bh-fMRI using short breath-hold periods, which are practical for clinical use. Methods: In a prospective study, 50 healthy subjects underwent three self-paced, end-expiration bh-fMRI sessions with 9 s breath-hold periods at 3T. A 30 min break between the second and third sessions was included. The reproducibility of the percentage signal change (PSC) in predefined volumes of interest for a ±0 s, ±3 s and ±6 s interval around the cerebellar peak (IAP)) was evaluated. The intraclass correlation coefficient (ICC) and the intra-personal coefficient of variation (CVintra) were calculated between the individual sessions. Results: This study demonstrated excellent reproducibility, with an ICC (2, k) for a ±0 s IAP across all sessions at 0.887 (95% CI: 0.882–0.892). The ICC values remained within an excellent range even when the participants left the scanner between sessions. The CVintra for the ±0 s IAP (14.54% ± 8.54%) remained below the 33% fiducial limit. A larger IAP revealed higher ICC values but higher CVintra values and lower PSC values. Conclusions: Bh-fMRI with 9 s breath-hold periods yields highly reproducible CVR assessments, supporting its feasibility for clinical implementation. Full article
(This article belongs to the Special Issue Diagnostic Imaging in Neurological Diseases)
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19 pages, 1363 KiB  
Article
Non-Structural Carbohydrate Concentration Increases and Relative Growth Decreases with Tree Size in the Long-Lived Agathis australis (D.Don) Lindl.
by Julia Kaplick, Benjamin M. Cranston and Cate Macinnis-Ng
Forests 2025, 16(8), 1270; https://doi.org/10.3390/f16081270 - 3 Aug 2025
Viewed by 191
Abstract
The southern conifer Agathis australis (D.Don) Lindl. is a large and long-lived species endemic to Aotearoa New Zealand. It is threatened due to past logging activities, pathogen attack and potentially climate change, with increasing severity and frequency of drought and heatwaves across its [...] Read more.
The southern conifer Agathis australis (D.Don) Lindl. is a large and long-lived species endemic to Aotearoa New Zealand. It is threatened due to past logging activities, pathogen attack and potentially climate change, with increasing severity and frequency of drought and heatwaves across its distribution. Like many large tree species, little is known about the carbon dynamics of this ecologically and culturally significant species. We explored seasonal variations in non-structural carbohydrates (NSCs) and growth in trees ranging from 20 to 175 cm diameter at breast height (DBH). NSCs were seasonally stable with no measurable pattern across seasons. However, we found growth rates standardised to basal area and sapwood area (growth efficiency) declined with tree age and stem NSC concentrations (including total NSCs, sugars and starch) all increased as trees aged. Total NSC concentrations were 0.3%–0.6% dry mass for small trees and 0.8%–1.8% dry mass for larger trees, with strong relationships between DBH and total NSC, sugar and starch in stems but not roots. Cumulative growth efficiency across the two-year study period declined as tree size increased. Furthermore, there was an inverse relationship between growth efficiency across the two-year study period and NSC concentrations of stems. This relationship was driven by differences in carbon dynamics in trees of different sizes, with trees progressing to a more conservative carbon strategy as they aged. Simultaneously declining growth efficiency and increasing NSC concentrations as trees age could be evidence for active NSC accumulation to buffer against carbon starvation in larger trees. Our study provides new insights into changing carbon dynamics as trees age and may be evidence for active carbon accumulation in older trees. This may provide the key for understanding the role of carbon processes in tree longevity. Full article
(This article belongs to the Section Forest Ecophysiology and Biology)
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19 pages, 18533 KiB  
Article
Modeling of Marine Assembly Logistics for an Offshore Floating Photovoltaic Plant Subject to Weather Dependencies
by Lu-Jan Huang, Simone Mancini and Minne de Jong
J. Mar. Sci. Eng. 2025, 13(8), 1493; https://doi.org/10.3390/jmse13081493 - 2 Aug 2025
Viewed by 133
Abstract
Floating solar technology has gained significant attention as part of the global expansion of renewable energy due to its potential for installation in underutilized water bodies. Several countries, including the Netherlands, have initiated efforts to extend this technology from inland freshwater applications to [...] Read more.
Floating solar technology has gained significant attention as part of the global expansion of renewable energy due to its potential for installation in underutilized water bodies. Several countries, including the Netherlands, have initiated efforts to extend this technology from inland freshwater applications to open offshore environments, particularly within offshore wind farm areas. This development is motivated by the synergistic benefits of increasing site energy density and leveraging the existing offshore grid infrastructure. The deployment of offshore floating photovoltaic (OFPV) systems involves assembling multiple modular units in a marine environment, introducing operational risks that may give rise to safety concerns. To mitigate these risks, weather windows must be considered prior to the task execution to ensure continuity between weather-sensitive activities, which can also lead to additional time delays and increased costs. Consequently, optimizing marine logistics becomes crucial to achieving the cost reductions necessary for making OFPV technology economically viable. This study employs a simulation-based approach to estimate the installation duration of a 5 MWp OFPV plant at a Dutch offshore wind farm site, started in different months and under three distinct risk management scenarios. Based on 20 years of hindcast wave data, the results reveal the impacts of campaign start months and risk management policies on installation duration. Across all the scenarios, the installation duration during the autumn and winter period is 160% longer than the one in the spring and summer period. The average installation durations, based on results from 12 campaign start months, are 70, 80, and 130 days for the three risk management policies analyzed. The result variation highlights the additional time required to mitigate operational risks arising from potential discontinuity between highly interdependent tasks (e.g., offshore platform assembly and mooring). Additionally, it is found that the weather-induced delays are mainly associated with the campaigns of pre-laying anchors and platform and mooring line installation compared with the other campaigns. In conclusion, this study presents a logistics modeling methodology for OFPV systems, demonstrated through a representative case study based on a state-of-the-art truss-type design. The primary contribution lies in providing a framework to quantify the performance of OFPV installation strategies at an early design stage. The findings of this case study further highlight that marine installation logistics are highly sensitive to local marine conditions and the chosen installation strategy, and should be integrated early in the OFPV design process to help reduce the levelized cost of electricity. Full article
(This article belongs to the Special Issue Design, Modeling, and Development of Marine Renewable Energy Devices)
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21 pages, 6618 KiB  
Article
Comparison of Deep Learning Models for LAI Simulation and Interpretable Hydrothermal Coupling in the Loess Plateau
by Junpo Yu, Yajun Si, Wen Zhao, Zeyu Zhou, Jiming Jin, Wenjun Yan, Xiangyu Shao, Zhixiang Xu and Junwei Gan
Plants 2025, 14(15), 2391; https://doi.org/10.3390/plants14152391 - 2 Aug 2025
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Abstract
As the world’s largest loess deposit region, the Loess Plateau’s vegetation dynamics are crucial for its regional water–heat balance and ecosystem functioning. Leaf Area Index (LAI) serves as a key indicator bridging canopy architecture and plant physiological activities. Existing studies have made significant [...] Read more.
As the world’s largest loess deposit region, the Loess Plateau’s vegetation dynamics are crucial for its regional water–heat balance and ecosystem functioning. Leaf Area Index (LAI) serves as a key indicator bridging canopy architecture and plant physiological activities. Existing studies have made significant advancements in simulating LAI, yet accurate LAI simulation remains challenging. To address this challenge and gain deeper insights into the environmental controls of LAI, this study aims to accurately simulate LAI in the Loess Plateau using deep learning models and to elucidate the spatiotemporal influence of soil moisture and temperature on LAI dynamics. For this purpose, we used three deep learning models, namely Artificial Neural Network (ANN), Long Short-Term Memory (LSTM), and Interpretable Multivariable (IMV)-LSTM, to simulate LAI in the Loess Plateau, only using soil moisture and temperature as inputs. Results indicated that our approach outperformed traditional models and effectively captured LAI variations across different vegetation types. The attention analysis revealed that soil moisture mainly influenced LAI in the arid northwest and temperature was the predominant effect in the humid southeast. Seasonally, soil moisture was crucial in spring and summer, notably in grasslands and croplands, whereas temperature dominated in autumn and winter. Notably, forests had the longest temperature-sensitive periods. As LAI increased, soil moisture became more influential, and at peak LAI, both factors exerted varying controls on different vegetation types. These findings demonstrated the strength of deep learning for simulating vegetation–climate interactions and provided insights into hydrothermal regulation mechanisms in semiarid regions. Full article
(This article belongs to the Section Plant Modeling)
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