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Red- and near-infrared (NIR)-emissive quantum dots (QDs) hold great promise in optoelectronic devices, sensors, and biomedicine owing to their advantages of low optical scattering, deep-tissue penetration, and compatibility with advanced photonic technologies. However, the toxicity of conventional cadmium (Cd)- and lead (Pb)-based QDs has led to growing demand for eco-friendly alternatives. Here, we provide a comprehensive review of sustainable classes of red/NIR-emissive QDs, including indium phosphide (InP), I-III-VI chalcogenides (CuInS₂, AgInSe, and so on), group-IV (Si, Ge, and SiGe) nanocrystals, and carbon-based QDs (graphene QDs or carbon dots). InP QDs are leading candidates for display technologies due to their high efficiencies and narrow bandwidths in emission properties, enabled by advanced core/shell engineering. In contrast, I-III-VI chalcogenides, group-IV, and carbon-based QDs offer advantages for biocompatible NIR bioimaging, photothermal therapy, and silicon photonics integration. We discuss synthesis strategies for achieving long-wavelength emission, the mechanisms of red/NIR photoluminescence (PL), and representative applications in displays, sensors, and bioimaging. Finally, we outline the remaining challenges, such as large-scale manufacturing and long-term stability, which should be addressed for commercial and clinical viability. Full article

(This article belongs to the Special Issue Advances in Sensing Technology: From Photon, Electron to Signal Processing)

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14 pages, 3206 KB

Open AccessArticle

Functional Characterization and Mutagenesis Studies of a Microbial-like Diterpene Synthase from Huperzia serrata

by Ting He, Yao Zhao, Xin Li, Bao Chen, Fangyan Chen and Baofu Xu

Molecules 2026, 31(8), 1329; https://doi.org/10.3390/molecules31081329 (registering DOI) - 17 Apr 2026

Abstract

Over the past decade, an increasing number of functional microbial-like terpene synthases (MTPSLs) have been reported in non-seed plants. However, whether the traditional Chinese medicinal plant H. serrata harbors such enzymes and their corresponding functions remains unexplored. In this study, we mined the transcriptome of H. serrata and identified a microbial-like terpene synthase, HsMTPSL1, which produces multiple diterpene products. Following isolation and structural elucidation, seven distinct compounds were obtained, representing three skeletal types: spatane, prenylkelsoene-type, and biflorane. Among these, compound 7 is a novel biflorane diterpene. Structural analysis and subsequent mutagenesis revealed critical residues governing the formation of distinct skeletons, uncovering the multifunctional nature of this enzyme. Notably, the S224A mutation significantly enhanced the production of spatane diterpene compound 1 by 11.6-fold, demonstrating the potential for protein engineering to improve the yield of this bioactive marine-specific diterpene. Transcriptomic profiling revealed that HsMTPSL1 is highly expressed in sporangia, and co-expression analysis with cytochrome P450s identified the CYP781 subfamily as candidates potentially involved in the downstream modification of these skeletons. Collectively, we report the first MTPSL from H. serrata and characterize it as a multifunctional diterpene synthase. Through structure-guided mutagenesis, we uncovered the molecular basis of its functional versatility, with the S224A mutation providing a powerful tool for enhancing the yields of all three diterpene skeletons, thereby laying a foundation for future protein engineering and synthetic biology applications. Full article

(This article belongs to the Section Chemical Biology)

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21 pages, 2518 KB

Open AccessArticle

Schleiferilactobacillus harbinensis JNDM Postbiotics Alleviate Atopic Dermatitis with Concurrent Changes in Gut Microbiota and Fecal SCFAs

by Zhijie Shi, Ke Li, Jiaqian Liang, Laifa Yan, Yuzhen Guo, Zhenming Lu, Xiaojuan Zhang, Hongyu Xu and Jinsong Shi

Microorganisms 2026, 14(4), 913; https://doi.org/10.3390/microorganisms14040913 - 17 Apr 2026

Abstract

Atopic dermatitis (AD) is a chronic inflammatory dermatosis driven by skin barrier dysfunction, immune dysregulation, and gut–skin axis imbalance. While probiotics show promise, the therapeutic potential and mechanisms of topical postbiotics in modulating the gut–skin axis remain understudied. Here, we investigated the efficacy of Schleiferilactobacillus harbinensis JNDM-derived cell-free supernatant (CFS) and lysate (ShL) in a DNFB-induced AD mouse model. Topical application of both CFS and ShL significantly attenuated AD-like symptoms, reduced epidermal thickening, and restored the expression of the barrier protein filaggrin. Immunologically, treatment suppressed the Th2-dominant inflammatory cascade (IL-4, IL-5, IL-13, IL-33, TSLP) and reduced serum IgE and IFN-γ levels. Notably, ShL exhibited superior systemic efficacy, significantly inhibiting mast cell infiltration and reducing the spleen index. 16S rRNA sequencing revealed that topical intervention remotely remodeled the gut microbiota, specifically reversing the depletion of the beneficial genus Alistipes and suppressing the compensatory increase in Odoribacter. This microbial restructuring was accompanied by distinct metabolic changes: ShL treatment resulted in an approximately 4-fold elevation in fecal butyrate concentrations compared with the model group. Correlation analysis further validated a strong positive axis linking Alistipes abundance and butyrate levels to skin barrier integrity. Collectively, our findings demonstrate that S. harbinensis postbiotics—particularly the lysate—ameliorate AD through a dual mechanism of local barrier repair and systemic metabolic modulation via the gut–skin axis, presenting a promising non-steroidal therapeutic strategy. Full article

(This article belongs to the Section Medical Microbiology)

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19 pages, 4385 KB

Open AccessArticle

Impact of Climate Warming on Cropland Water Use Efficiency in Northeast China Based on BESS Satellite Data

by Fenfen Guo, Haoran Wu, Zhan Su, Yanan Chen, Jiaoyue Wang and Xuguang Tang

Remote Sens. 2026, 18(8), 1223; https://doi.org/10.3390/rs18081223 - 17 Apr 2026

Abstract

Understanding the long-term dynamics of cropland water use efficiency (WUE) and its underlying environmental drivers is essential for ensuring food and water security, particularly for regions facing intensified climate change. Here, we investigated the spatial patterns and long-term trends of gross primary productivity (GPP), evapotranspiration (ET), and WUE in cropland ecosystems across Northeast China during the past two decades as the nation’s primary commodity grain base using the time-series Breathing Earth System Simulator (BESS) products. Subsequently, the ridge regression method was used to quantitatively disentangle the relative contributions of key climatic variables to the observed WUE trends of cropland. Our results revealed a pronounced decreasing gradient in both GPP and ET along the southeast–northwest direction. A significant increase in GPP was observed over the 20-year period (p < 0.01), with 95.94% of the cropland area showing positive trends. ET showed a slight, non-significant increase (p > 0.05), though 82.77% of pixels exhibited positive trends, particularly in the northwest. Consequently, WUE showed a widespread and significant enhancement (p < 0.01), with approximately 98% of cropland pixels exhibiting increasing trends. Attribution analysis identified air temperature as the dominant environmental variable, accounting for 92.4% of the observed WUE increase, while solar radiation and precipitation contributed modestly (3.4% and 3.2%, respectively). Our findings underscore the predominant role of thermal conditions in shaping the carbon–water coupling efficiency of agroecosystems in semi-arid to semi-humid transition zones. This study provides quantitative evidence that warming climate, rather than changes in water availability or radiation, has been the primary climatic factor driving the improved cropland WUE over the past two decades. These insights have important implications for developing adaptive water management strategies to enhance agricultural climate resilience in Northeast China and similar regions worldwide. Full article

(This article belongs to the Section Remote Sensing in Agriculture and Vegetation)

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21 pages, 5473 KB

Open AccessArticle

Reproducibility of 4D Flow MRI-Derived Diastolic Function Testing by Mitral and Pulmonary Venous Flow Indices in Healthy Volunteers

by Thomas in de Braekt, Paul R. Roos, Patrick Houthuizen, Harrie C. M. van den Bosch, Hildo J. Lamb and Jos J. M. Westenberg

Appl. Sci. 2026, 16(8), 3930; https://doi.org/10.3390/app16083930 - 17 Apr 2026

Abstract

Accurate assessment of mitral valve (MV) and pulmonary vein (PV) flow velocities is important for left ventricular diastolic function testing. This study investigated the scan–rescan reproducibility of 4D Flow MRI-assessed MV and PV flow velocities in 21 healthy volunteers (25 ± 4 years). Participants underwent repeated whole-heart 3T 4D Flow MRI involving repositioning and different respiratory compensation strategies (motion-uncompensated free-breathing vs. respiratory motion-compensated navigator gating). MV parameters (net flow volume (NFV), E-wave velocity, A-wave velocity, E/A ratio, E deceleration time (DT), annular e’ velocity, E/e’ ratio) and PV parameters (NFV, S-wave velocity, D-wave velocity, S/D ratio, atrial reversal (AR) wave velocity) were derived from velocity–time curves and compared using intraclass correlation coefficients (ICCs), Bland–Altman analysis, and Pearson’s correlation (r). Results showed significant moderate-to-strong scan–rescan agreement and correlation for most MV and PV parameters (ICC = 0.51–0.92; r = 0.51–0.92; all p < 0.05), except E DT, e’ velocity, E/e’ ratio, PV NFV, and AR velocity (ICC = −0.13–0.47; r = −0.14–0.47). Subanalysis of respiratory motion strategies showed moderate-to-strong agreement and correlation for MV and PV parameters (ICC = 0.61–0.99; r = 0.52–0.99; all p < 0.05 excluding E DT), except E DT (ICC = 0.44) and PV NFV (ICC = 0.46; r = 0.46). While intraobserver agreement was mostly moderate-to-excellent (ICC = 0.58–0.97; ICC = 0.41 for E DT), interobserver agreement was poor for E DT and PV parameters (ICC = −0.12–0.34). Overall, 4D Flow MRI shows acceptable reproducibility for selected diastolic flow parameters, particularly mitral inflow indices, but substantial variability and limited robustness for key indices currently restrict its clinical applicability. Full article

(This article belongs to the Special Issue Biomedical Imaging Technologies for Cardiovascular Disease, 4th Edition)

16 pages, 2060 KB

Open AccessArticle

Comparison of Absolute and Individualized Physical Activity Intensity Thresholds Using Non-Dominant Wrist-Worn Accelerometry in Military Office Workers

by Maaike Polspoel, Tara Reilly, Damien Van Tiggelen and Patrick Calders

Appl. Sci. 2026, 16(8), 3931; https://doi.org/10.3390/app16083931 - 17 Apr 2026

Abstract

Accurate classification of physical activity (PA) intensity is essential for exercise prescription, rehabilitation monitoring, and evaluation of guideline adherence. However, widely used wrist-worn accelerometer cut-points may substantially misclassify physiological intensity. This study evaluated absolute accelerometer thresholds during a maximal 2400 m run in military office workers and examined whether individualized cut-points improve agreement with physiological intensity. Seventy-four military office workers completed the test while wearing a wrist-worn ActiGraph GT9X Link and a chest-worn Zephyr BioHarness. Participants achieved near-maximal physiological effort, with peak heart rate averaging 187 ± 11 bpm (95 ± 4.2% age-predicted HRmax). Despite this high intensity, absolute wrist-worn cut-points classified only 34.5% of participants as performing vigorous activity for most of the test. Individualized cut-points, derived from each participant’s individual reference intensity, calculated as the three highest consecutive one-minute epochs during the 2400 m test, substantially improved agreement between accelerometer-derived classifications and physiological intensity. Agreement with %HRmax increased from fair (κ = 0.31), using absolute thresholds, to good (κ = 0.74), using individualized thresholds, and intraclass correlation increased from 0.52 to 0.81. These findings demonstrate that absolute cut-points markedly underestimate high-intensity activity, potentially leading to inaccurate exercise load monitoring and misinterpretation of training intensity. Individualized calibration during a standardized maximal running test provides a feasible strategy to improve the validity of intensity assessment using wearables. Although the study population consisted of military office workers, the approach may be applicable to other active populations. However, further validation in independent samples is needed. Full article

(This article belongs to the Special Issue Sports Medicine, Exercise, and Health: Latest Advances and Prospects: 2nd Edition)

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19 pages, 3835 KB

Open AccessArticle

Reinforcement of Thermo-Compressed Sodium Alginate Films with Calcium Alginate Powder

by Prasong Srihanam, Wilaiwan Simchuer, Vanseng Chounlamany, Kesiny Phomkeona, Phengxay Deevanhxay and Yodthong Baimark

Mar. Drugs 2026, 24(4), 142; https://doi.org/10.3390/md24040142 - 17 Apr 2026

Abstract

Alginate is a biocompatible and biodegradable polymer derived from seaweed. It has been extensively researched and developed for various applications. However, its poor mechanical properties present a significant drawback that limits its use in multiple fields. Furthermore, the fabrication of reinforced alginate films using conventional melt processing has the potential for scaling up production. This study aimed to enhance the mechanical properties of sodium alginate (SA) films by incorporating calcium alginate (CA) powder. The SA/CA biocomposite films were created using a thermo-compression technique, with glycerol acting as a plasticizer for the SA matrix. Various CA contents—2.5, 5, 10, and 20 wt%—were investigated. Scanning electron microscopy and energy dispersive spectroscopy revealed good interfacial adhesion between the SA film matrix and the CA powder. As the CA content increased, the moisture content of SA/CA biocomposite films decreased. The addition of CA powder significantly improved the tensile properties of the SA films. Based on the tensile test, SA/CA biocomposite films with 20 wt% CA powder exhibited a maximum tensile strength of 11.7 MPa and a Young’s modulus of 234.7 MPa. These results indicate a substantial increase of 208% in maximum tensile strength and 907% in Young’s modulus compared to SA films without CA. These findings indicated that the CA powder serves as an effective reinforcing filler for thermo-compressed SA films, which could lead to the development of high-strength alginate-based products for potential use in various applications, including biomedical, agricultural, and packaging applications. Full article

(This article belongs to the Special Issue Marine Polysaccharides-Based Biomaterials)

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17 pages, 690 KB

Open AccessArticle

The In Vitro Multifaceted Biological Activity of Catechins in Relation to Their Oxidation Potentials

by Małgorzata Wronkowska, Danuta Zielińska, Małgorzata Starowicz, Mateusz Szydłowski, Mariusz Konrad Piskuła and Henryk Zieliński

Molecules 2026, 31(8), 1328; https://doi.org/10.3390/molecules31081328 - 17 Apr 2026

Abstract

In this study, the rank of multifaceted activity of catechin (C), epicatechin (EC), epigallocatechin (EGC), epicatechin-3-gallate (ECG) and epigallocatechin-3-gallate (EGCG) was addressed. Their antioxidant activity was determined by the differential pulse voltammetry (DPV), whereas their ability to inhibit angiotensin-converting enzyme (ACE) activity, acetylcholinesterase activity (AChE), and formation of the advanced glycation end-products (AGEs) was performed in a model system to show their importance against hypertension, Alzheimer-type dementia, and diabetic’s complication, respectively. The order of the antioxidant potential of catechins in comparision to gallic acid (GA) was EGCG > ECG > EC > EGC ≈ C > GA, whereas the order of the ACE inhibitory activity was EGCG > ECG > EGC > EC > C, thus indicating the importance of the structure–activity relationship. The correlation between IC₅₀ for ACE inhibition of catechins and their antioxidant activity had the value r = −0.60. The order of the AChE enzyme inhibitory activity was EGCG ≈ EGC > ECG > EC > C, and the weak positive correlation between IC₅₀ and the first anodic peak potential (E_pa1) values was noted (r = 0.67). The ranking of the anti-AGE activities was EGCG ≈ ECG > EGC > EC > C, and a negative correlation between the inhibitory activity of catechins against AGE formation and their antioxidant activity was r = −0.82, whereas a positive correlation (r = 0.88) was noted between their first anodic peak potential (E_pa1) values. The provided results expand our knowledge on the multifaceted activity of catechins, indicating EGCG and ECG as the most active antioxidants against inhibition of ACE and AChE as well as towards AGE formation. Full article

(This article belongs to the Special Issue Natural Compounds for Disease and Health, 4th Edition)

18 pages, 1030 KB

Open AccessArticle

Regional Disparities and Associated Factors Underlying CDC Health Professional Distribution in China

by Jiayi Zheng, Tong Hu, Shandan Xu, Jing Xiao and Change Xiong

Healthcare 2026, 14(8), 1079; https://doi.org/10.3390/healthcare14081079 - 17 Apr 2026

Abstract

Aim: The aim of this study was to explore the distribution and driving factors influencing the disparity of health professionals (HPs) at the Centers for Disease Control and Prevention (CDC) in China and to provide a reference for regional health planning and rational allocation of public health resources. Methods: The Gini coefficient was used to measure the equity of HP distribution at CDC sites at the provincial level during 2012–2023 in China. Moran’s I was used to analyze the spatial agglomeration effect, and the geographic detector model was used to explore the factors driving the allocation of HPs at CDC sites in different provinces. Results: The number of HPs at the CDC showed an increasing trend from 2012 to 2023 in China. The average Gini coefficients at the population and geographical areas were 0.16 and 0.58, respectively. The global Moran’s I statistic indicated a notable decline in spatial clustering for the population dimension, decreasing from 0.503 to 0.238; in contrast, spatial clustering for the geographical dimension remained relatively stable, ranging between 0.13 and 0.16. The local Moran’s I statistic revealed that provinces such as Qinghai in the western China consistently exhibited a “low–low” spatial clustering pattern. Six factors were found to explain the variability in the CDC HP distribution based on the 2020 data. In the context of factor interactions, the synergistic effects between education level and health expenditure share (q = 0.9781), and between population aging and per capita GDP (q = 0.9699), substantially exceed the explanatory power attributable to any single factor alone. Conclusions: A significant regional disparity was observed in the distribution of HPs among 31 provinces, with the distribution based on service area being less equitable than that based on population. The shortage of healthcare professionals in the western region is characterized by notably inadequate geographical distribution. Future policy initiatives should prioritize targeted spatial interventions and integrated, multi-factor collaborative strategies. Full article

14 pages, 420 KB

Open AccessArticle

Influence of Adventist Spirituality on Self-Control and Perceived Stress Among Seventh-Day Adventist Adults in Coastal Peru

by Gunther Alonso Huaytalla Sanchez, Juan Marcelo Zanga Céspedes, Zembe Alejandro Saito Roncal and Jacksaint Saintila

Healthcare 2026, 14(8), 1078; https://doi.org/10.3390/healthcare14081078 - 17 Apr 2026

Abstract

Background: Adventist spirituality has been identified as a relevant psychosocial resource for emotional well-being; however, evidence on its relationship with self-control and perceived stress in specific religious populations remains limited. Objective: The aim of this study was to examine the associations between Adventist spirituality, self-control, and perceived stress in a sample of adults belonging to the Seventh-day Adventist Church and residing in coastal regions of Peru. Methods: A cross-sectional study was conducted between December 2025 and January 2026 with 506 Seventh-day Adventist adults who completed an online questionnaire. Adventist spirituality was assessed using the Mission Commitment Questionnaire, which captures religious–spiritual commitment through three dimensions: personal devotion, participation, and witnessing. Self-control and perceived stress were measured using standardized scales. Data were analyzed using partial least squares structural equation modeling. Results: The constructs showed adequate internal consistency, with Cronbach’s alpha values ranging from 0.875 to 0.951 and composite reliability values ranging from 0.906 to 0.956. Adventist spirituality was positively associated with self-control (β = 0.479, p < 0.001) and negatively associated with perceived stress (β = −0.457, p < 0.001). Personal devotion showed the strongest contribution to the higher-order spirituality construct. The model explained 22.9% of the variance in self-control and 20.9% of the variance in perceived stress. Conclusions: Adventist spirituality, particularly personal devotion, was associated with higher self-control and lower perceived stress. Although the cross-sectional design does not allow causal inference, the findings support the relevance of Adventist spirituality as a psychosocial resource linked to emotional well-being in this religious population and justify future longitudinal studies. Full article

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21 pages, 1087 KB

Open AccessReview

The Evolution of Blood Pressure Thresholds and Targets over Time: A Historical Review

by Maria Elena Flacco, Flavia Minoia, Gabriele Brunini, Martina Rosticci, Matteo Fiore, Giancarlo Cicolini, Cecilia Acuti Martellucci, Claudio Borghi and Lamberto Manzoli

Med. Sci. 2026, 14(2), 203; https://doi.org/10.3390/medsci14020203 - 17 Apr 2026

Abstract

The definition of hypertension and the values of systolic and diastolic blood pressure (BP) that should be considered as therapeutic targets have changed over time and vary across scientific societies, which may generate uncertainty in the decision-making process among clinicians and patients. We traced the evolution and described the differences in all the 32 Clinical Practice Guidelines for the management of hypertension released by the following national and international scientific societies: World Health Organization—WHO; International Society of Hypertension—ISH; Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure—JNC; American Heart Association—AHA; American College of Cardiology—ACC; European Society of Cardiology—ESC; European Society of Hypertension—ESH; and UK National Institute for Health and Care Excellence—NICE. Throughout the decades, the BP values used for hypertension definition, treatment initiation, and targets to achieve started from SBP/DBP ≥ 160/95 mmHg, established at the end of the 70s, progressively decreased, and were differentiated by individual cardiovascular risk. In the last decade, a divergent approach emerged across scientific societies: while WHO/ISH and NICE recommended thresholds and targets for the general population at SBP/DBP < 140/90 mmHg, ESH/ESC and ACC/AHA guidelines further and markedly reduced both BP threshold values and therapeutic targets, recommending as ideal SBP/DBP values < 130/80 mmHg and encouraging an SBP < 120 mmHg. Discrepancies also emerged in the assessment of the quality of the evidence: although the methodological approaches largely improved over time and across all the institutions assessed, various degrees of incompleteness on the adopted scales were reported, and potentially conflicting situations emerged, particularly when weaker evidence was used to build strong recommendations. Although some degree of discrepancy among guidelines is expected, some of the differences are large and can lead to widely different approaches in the management of BP control. A standardization of the methodology and interpretation of the evidence supporting the guidelines may help to reduce the variability in order to provide the best possible guidance for clinical practice and patient health. Full article

(This article belongs to the Section Cardiovascular Disease)

7 pages, 430 KB

Open AccessCase Report

Imported Pediatric Lyme Disease in Singapore—A Case Series

by Ade Xin Ning Tan, Ilyas Hussin, Chia Yin Chong, Matthias Maiwald, Terri Xiao-Bei Chiong and Natalie Woon Hui Tan

Pathogens 2026, 15(4), 437; https://doi.org/10.3390/pathogens15040437 - 17 Apr 2026

Abstract

Lyme disease is the most common reported vector-borne disease in North America and is also highly prevalent across Europe. Although tick-borne diseases are uncommon in Singapore, there remains a risk of imported tick-borne diseases among travelers from endemic regions. We present a case series of three pediatric patients with imported Lyme disease managed at a tertiary children’s hospital in Singapore, illustrating the varied clinical presentations of Lyme disease in children. One child developed meningitis following prior antibiotic therapy for Lyme disease, although causality cannot be definitively established. This series aims to highlight key diagnostic considerations and management principles relevant to clinicians practicing in non-endemic regions. Full article

(This article belongs to the Special Issue Ticks and Tick-Borne Diseases in Southeast Asia)

28 pages, 6363 KB

Open AccessArticle

Relationship of Multifractal and Entropic Properties of Global Seismic Noise with Major Earthquakes, 1997–2025

by Alexey Lyubushin and Eugeny Rodionov

Fractal Fract. 2026, 10(4), 267; https://doi.org/10.3390/fractalfract10040267 - 17 Apr 2026

Abstract

A method for analyzing long-term (1997–2025) continuous records of low-frequency global seismic noise measured at a network of 229 broadband seismic stations distributed across the Earth’s surface is proposed in this study. The method is based on the use of nonlinear multifractal and entropy statistics, evaluated daily in successive time intervals, of first-principal component analysis, correlation analysis, and parametric models of point process intensity. The relationships between changes in seismic noise properties and the response of noise properties to the irregularity of the Earth’s rotation with the sequence of strong earthquakes, including those of a predictive nature, are investigated. Full article

(This article belongs to the Special Issue Fractals in Earthquake and Atmospheric Science)

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