Search Results (6,176)

Beyond their classical role as “cellular powerhouses”, mitochondria are increasingly recognized as dynamic and interconnected networks whose architecture, quality control, and intercellular communication influence cellular and organismal homeostasis. Mitochondrial dynamics—including fusion–fission balance, mitophagy–biogenesis coupling, intracellular organization, and intercellular transfer via tunneling nanotubes, extracellular vesicles, or transient cell fusion—contribute to tissue adaptation and functional decline during aging. Focusing on cardiac muscle, skeletal muscle, and the nervous system, this narrative review synthesizes current evidence describing how aging disrupts mitochondrial network integrity through altered dynamics, impaired organelle positioning and transport, reduced mitophagy, mtDNA instability, and compromised metabolic coupling between cells. These alterations propagate across tissues, limiting energetic flexibility, stress resilience, and regenerative capacity. Building on these mechanisms, we discuss a systems-level perspective in which aging is associated with progressive loss of mitochondrial network coherence rather than solely cumulative molecular damage. Within this framework, mitochondrial connectivity functions as an integrative descriptor of cellular resilience: well-organized networks counteract metabolic perturbations, whereas functionally decoupled networks amplify stress and promote maladaptive aging trajectories. Emerging evidence indicates that physiological and pharmacological interventions, including endurance exercise, caloric restriction or mimetics, fusion-supporting pathways, and mitophagy-enhancing strategies, can partially restore network organization even later in life. Molecular, cellular, and tissue-level insights are integrated to highlight mitochondrial network dynamics as both a mechanistic contributor to aging and a potentially modifiable target for future preventive and therapeutic interventions. Full article

Background: Shoulder injuries are highly prevalent in handball due to repetitive overhead actions and high mechanical demands, particularly in athletes with a history of previous injury who remain at increased risk of recurrence. Reliable monitoring of shoulder function is essential, and tele-assessment has emerged as a potential alternative to traditional face-to-face evaluation. The aim of this study was to evaluate the level of agreement between face-to-face and tele-assessment methods for measuring shoulder range of motion, dynamic stability, muscular endurance, and scapular dyskinesia in female handball players with a history of shoulder injury. Methods: A cross-sectional agreement study was conducted in 25 competitive female handball players with a history of shoulder injury. Each participant underwent two evaluations (face-to-face and videoconference-based) performed by experienced physiotherapists in randomized order within the same session. Outcomes included shoulder range of motion, dynamic stability assessed by the Upper Quarter Y Balance Test, muscular endurance, and scapular dyskinesia. Agreement between methods was analyzed using two-way random-effects intraclass correlation coefficients. Results: Excellent agreement was observed for range of motion, dynamic stability, and muscular endurance (ICC = 0.96–1.00), with narrow confidence intervals. Scapular dyskinesia demonstrated good agreement (Cohen’s Kappa coefficient 0.59 (p < 0.05)). Mean differences between face-to-face and tele-assessment were minimal, ranging from 0.04° to 0.31° for ROM and 0.10 cm to 0.16 cm for stability measures. Conclusions: Tele-assessment provides clinically comparable results to in-person evaluation and may represent a feasible and reliable tool for remote monitoring of shoulder function in female overhead athletes with a history of injury. Full article

Urban heritage structures are most commonly understood as memorial artifacts, tourism assets, or redevelopment resources. While this common view acknowledges cultural and economic value, it overlooks a deeper function of heritage within the long evolution of human settlements. This paper advances a counter thesis: in addition to its historic contingencies and power relationships—which are real, but only part of the picture—urban heritage embodies valuable but often hidden intelligence that is highly relevant to contemporary urban challenges. Specifically, heritage environments encode useful structured information about spatial configurations that have gained adaptive value over time in a process known as stigmergy. Drawing on complexity science, network theory, the mathematics of symmetry, and theories of extended cognition, the paper argues that enduring urban forms persist not only for symbolic or historical reasons, but because they embed structural properties conducive to resilience, legibility, social interaction, climatic adaptation, and human well-being. Recurring characteristics include fine-grained network connectivity, fractal scaling hierarchies, organized symmetry, articulated thresholds, and biophilic integration. Evidence from environmental psychology, public health, and urban morphology suggests that such properties correlate with reduced stress, increased walkability, stronger social capital, and improved ecological performance. The paper proposes a methodological framework—what we call the Adaptive Patterns Model—for identifying, evaluating, and translating this embedded intelligence into contemporary regeneration practice. The Model is presented as a four-phase, conceptually synthesized framework—integrating insights from complexity science and stigmergy, urban morphological analysis, and pattern-language methodology—comprising documentation, pattern extraction, encoding, and performance correlation. It concludes by challenging a still-prevalent assumption that contemporary conditions invalidate accumulated spatial knowledge. Instead, urban heritage is understood as adaptive capital within an ongoing evolutionary process, offering a structurally grounded foundation for resilient urban transformation. Full article

Advancing environmental monitoring through coordinated autonomous systems is central to sustainable smart region governance and data-driven territorial management. The article presents an engineering-oriented architecture and deployment methodology for an integrated wildfire monitoring and response system that combines unmanned aerial vehicles (UAVs), unmanned ground vehicles (UGVs), and stationary sensor networks (SNs). We formalise hub-and-spoke infrastructure placement as a mixed-integer optimisation problem that accounts for platform types, endurance, travel times and logistical constraints, and propose a practical pre-processing pipeline (confidence scoring, resampling, Kalman/median filtering, strategy fusion) for heterogeneous telemetry and imagery. The system couples multimodal neural network processing (image backbones, clustering and time-series models) with online resource-allocation and mission-planning mechanisms to prioritise UAV/UGV sorties and dynamically select launch sites. The article describes scenario-driven operational modes (early warning, alarm verification, autonomous local extinguishing, post-fire recovery, sensor-gap compensation, and inter-hub reinforcement), defines validation protocols (synthetic experiments, precision/recall/F1, and hardware-in-the-loop testing), and proposes KPIs to assess environmental, social, and economic impacts for smart regions. The contribution is a reproducible, deployment-focused blueprint that bridges conceptual UAV–UGV–SN research and practical implementation, highlighting trade-offs in reliability, communication redundancy, and sustainability, and outlining directions for simulation, field pilots and algorithmic refinement. Full article

Background: Metabolic syndrome (MetS) leads to alterations in cardiac autonomic control that can be detected from electrocardiogram (ECG)-derived markers, particularly when the cardiovascular system is challenged during an oral glucose tolerance test (OGTT). Methods: In this paper, we present an automated framework for MetS identification using RR intervals and heart rate variability (HRV) features extracted from 12-lead ECG recordings acquired during the five OGTT stages in 40 male participants (15 with MetS, 10 controls, and 15 endurance-trained marathon runners). RR intervals were first derived using a multilead Pan-Tompkins approach with fusion-based validation. From these RR series, HRV descriptors were computed from time-domain statistics (RR mean, SDNN, rMSSD, pNN50), spectral indices (VLF, LF, HF, LF/HF), and nonlinear measures (SD1, SD2, SampEn, DFA-${\alpha }_1$). Conventional HRV analysis revealed pronounced physiological differences between groups: MetS subjects exhibited reduced parasympathetic activity, reflected by lower rMSSD and SD1, lower HF power, and higher LF/HF ratios, whereas marathoners showed greater vagal modulation, higher HF power, and increased signal complexity. Healthy controls showed an intermediate autonomic profile. Using RR sequences and HRV descriptors (256 samples per stage), we trained three multimodal classifiers: a CNN-MLP model with a softmax output, a CNN-MLP model with an SVM head, and a CNN + LSTM-MLP + SVM architecture. Results: All models achieved strong discriminative performance, with accuracies ranging from 0.92 to 0.95, F1-macro values from 0.92 to 0.95, and macro-AUC values from 0.96 to 0.97. The CNN-MLP model achieved the best overall performance, whereas the CNN + LSTM-MLP + SVM model showed strong class discrimination, particularly for endurance athletes, while maintaining competitive recall for MetS. Conclusions: These findings support the feasibility of ECG-based autonomic assessment as a complementary non-invasive approach for early metabolic risk detection in clinical and preventive cardiometabolic screening settings. Full article

Background/Objectives: Non-specific chronic neck pain is one of the biggest problems in the current population, with high levels of pain and disability and a decrease in the quality of life. The aim of this study is to assess possible variables that may be associated with neck pain, such as disability, pain, quality of life, sex, neck muscle endurance, active range of motion (AROM) and frequency of drug use. Methods: We performed a cross-sectional study of non-specific chronic neck pain with a total of 105 subjects. The variables pain-related disability, pain, quality of life, sex, AROM and frequency of drug use were evaluated. Results: A total of 105 patients with chronic neck pain were included (mean age 40.47 ± 12.18 years; 67.6% women). Neck pain–related disability showed significant negative correlations with all cervical AROM variables, particularly left rotation (r = −0.507) and right rotation (r = −0.489) (p < 0.001). Disability was also negatively correlated with health-related quality of life (r = −0.604) and positively correlated with pain intensity (r = 0.414) and frequency of drug consumption (r = 0.546) (p < 0.001). Regression analyses indicated that disability was associated with reduced left rotation mobility and higher drug consumption (R² = 0.424). Pain intensity was associated with female sex, reduced right rotation mobility, and higher drug consumption (R² = 0.246). Lower health-related quality of life was associated with higher drug consumption and female sex (R² = 0.174). Conclusions: Being female, having a reduction in active rotational mobility, and a high frequency of drug consumption are associated with greater pain-related disability and pain intensity, and a lower HRQoL in subjects with non-specific chronic neck pain. Full article

This comparative cross-sectional study simultaneously investigated the dual health burden of body mass index (BMI) and common mental disorders (CMDs) driven by occupational stressors in two stepwise regression models. By classifying stress exposure into three clinically relevant tiers (low, moderate, and severe) in two distinctive populations—a hospital and a manufacturing company—we used the validated SDS-30 and SRQ-20 instruments. The robust multiple regression models uncovered a highly nuanced landscape of employee well-being that highlights the context-dependent nature of psychosocial hazards. The most compelling findings emerged from the interaction analyses, which demonstrated that the physical and mental consequences of severe stress do not impact the workforce uniformly. Regarding mental health, severe occupational stress proved to be a potent catalyst for CMD symptoms, but this psychological toll was significantly magnified within the hospital sector relative to the manufacturing environment. An opposite, yet equally context-dependent, pattern emerged regarding physical health. In the main-effects-adjusted model, the severity of occupational stressors did not demonstrate a statistically significant linear association with an overall increase in BMI. However, the interaction model revealed a hidden vulnerability: employees in operational field roles who report severe stress are highly susceptible to severe BMI increases compared with admin personnel. While administrative staff may face sedentary risks, field workers under severe stress likely endure higher physiological allostatic load, erratic shift patterns that disrupt circadian metabolic rhythms, and potentially poorer dietary coping mechanisms during active labor. This combination of physical exhaustion and severe psychological tension severely disrupts metabolic homeostasis, forcing the redistribution of adipose tissue and driving the observed BMI spike. Full article

We introduce the concept of a one-way, broadband information package, the Cosmic Illuminating Gift, intended to provide distant intelligences with fundamental empirical data about the Universe. Unlike previous messaging to extraterrestrial intelligences (METI) that emphasized greetings or cultural identity, the Gift aims to transmit unbiased, universally interpretable information that recipients could not otherwise obtain due to their distinct spacetime position and epoch. By emphasizing raw observations, rather than human interpretations or cosmological models, the Gift aspires to serve as a neutral and enduring resource. A central assumption of the project is that any potential recipients are likely to possess a level of intelligence and technological sophistication far beyond our own. Accordingly, the content and encoding of the Gift are not designed to “teach” fundamentals, but to deliver compact, logically structured packets that such civilizations could decode even at extremely low signal-to-noise levels. This perspective shifts the challenge from brute-force transmission to ensuring that photons arrive in spectrally quiet windows and that the format is unmistakably artificial and distinguishable from astrophysical backgrounds. We outline strategies for content selection, encoding, and transmission that reflect this assumption. Practical implementation is feasible with current or near-term infrastructure, and future advances will only improve the quality of subsequent Gifts. Ultimately, the endeavor is unique among scientific projects in that it anticipates no feedback or measurable result within the span of our civilization’s timeline. Its significance lies instead in the act of contribution itself: offering a durable, universal dataset as a gesture of intellectual solidarity across cosmic distances. Full article

This article examines how ancient Greek tragedy mobilizes landscape to reflect on the limits of civic order and the conditions of human dwelling. Rather than treating mountains, groves, meadows, and borderlands as neutral settings or as simple “nature/culture” oppositions, it argues that tragic landscapes are ethically charged spaces where human norms meet forces that exceed political regulation—divine presence, necessity, vulnerability, and finitude. Written for the polis yet unsettled by what lies beyond it, tragedy repeatedly turns to extra-civic spaces to test civic stability. Three case studies develop the argument. In Hippolytus, woodland and meadow sustain an ideal of purity grounded in withdrawal, an orientation incompatible with social life and culminating in catastrophic isolation. In Bacchae, Pentheus’ project of spatial control collapses as Dionysian forces traverse walls and institutions with ease, exposing the limits of civic rationality. In Oedipus Tyrannus and Oedipus at Colonus, the tragic trajectory moves from Mount Cithaeron, a site of abandonment and opaque necessity, to the sacred grove at Colonus, where prolonged suffering enables a transformed relation to place, law, and divine power. Taken together, these plays suggest that the polis is never fully self-sufficient: civic order endures only through engagement with what it cannot master or expel, and spatial orientation is inseparable from ethical choice. Full article

This paper presents an experimental investigation of the level flight speed and endurance characteristics of a micro-class unmanned aerial vehicle as a function of operating weight. Wind tunnel experiments were conducted to determine the aerodynamic performance and power requirements of the UAV over a range of operating weight configurations. The tested vehicle, a fixed-wing micro UAV, was examined under steady, level flight conditions, with particular emphasis on identifying variations in the minimum power required to sustain level flight. Measured aerodynamic forces and moments were used to derive drag polars and the corresponding power curves for each mass configuration. Based on these results, endurance estimates were obtained by coupling the experimentally derived power requirements with the characteristics of the onboard electric propulsion system. The study demonstrates a clear shift in flight speeds with increasing operating weight, as well as a reduction in achievable endurance, highlighting the sensitivity of micro-class UAV performance to mass variations, and therefore energy consumption. Full article

Endurance performance is regulated through dynamic interactions between physiological capacity, nutritional status, and psychological control processes. While traditional endurance models have emphasized metabolic and cardiorespiratory determinants, growing evidence indicates that energy availability also influences cognitive function, perceived effort, and decision-making during prolonged exercise. This narrative review synthesizes current literature on the interplay between nutritional strategies and psychological regulation in endurance sports, with particular emphasis on low energy availability, carbohydrate availability, mental fatigue, and pacing behavior. Acute and chronic reductions in energy availability are associated not only with endocrine and metabolic disturbances but also with amplified perceived exertion, impaired executive functioning, reduced effort tolerance, and altered risk-related decision-making, even in the absence of overt physiological failure. Carbohydrate availability emerges as a central modulator operating through both peripheral mechanisms (substrate supply and glycogen preservation) and central neurocognitive pathways influencing perception, motivation, and fatigue regulation. Hydration status, caffeine ingestion, and gastrointestinal tolerance further interact with perceptual and cognitive processes to shape real-time pacing and endurance sustainability. Integrating sport nutrition and sport psychology provides a unifying framework for understanding endurance regulation as a multilevel process linking metabolic state to perceptual experience and behavioral decision-making. From an applied perspective, optimizing endurance performance requires maintenance of adequate long-term energy availability, strategic carbohydrate periodization aligned with training demands, and systematic monitoring of perceived effort alongside physiological load. Future research should prioritize interdisciplinary, ecologically valid designs combining metabolic, perceptual, and cognitive measurements, supported by wearable and data-driven technologies capable of capturing real-time endurance regulation. Bridging nutritional and psychological mechanisms within a unified conceptual model offers a stronger scientific basis for improving performance sustainability while safeguarding athlete health in modern endurance sport. Full article

Skeletal muscle development and physiological homeostasis are profoundly influenced by environmental cues. Among these factors, ambient temperature represents a critical determinant of growth performance and metabolic adaptation in mammals. However, the effects of different ambient temperature ranges on skeletal muscle characteristics and on responses across multiple visceral tissues remain poorly understood. In this study, five ambient temperature conditions (16 °C, 20 °C, 24 °C, 28 °C, and 32 °C) were established to investigate their physiological impacts in a mouse model. Our results demonstrate that ambient temperature markedly influences growth performance and skeletal muscle phenotype. Notably, mice housed at 20 °C showed relatively preserved grip strength and a shift in myofiber cross-sectional area distribution, although these findings did not consistently indicate superior skeletal muscle development across all indices. Further analysis revealed that ambient temperature significantly modulated the expression profiles of myosin heavy chain (MyHC) isoforms in skeletal muscle. Specifically, cold exposure was associated with an upregulation of the slow-twitch-related MyHC I, whereas heat stress correlated with an elevation of the fast-twitch-related MyHC IIb. Functional assessments indicated that exposure to colder or hotter conditions was associated with impaired muscle performance, as reflected by reduced grip strength at 16 °C, 28 °C, and 32 °C, and decreased endurance capacity at 28 °C and 32 °C. Histological analyses of major visceral organs revealed no obvious structural alterations in the heart, liver, spleen, lung, or kidney across temperature conditions. However, exposure to thermal extremes (16 °C and 32 °C) significantly reduced intestinal villus height, suggesting compromised intestinal integrity under temperature stress. Collectively, these findings indicate that ambient temperature is associated with multi-tissue changes in skeletal muscle characteristics, functional performance, and intestinal morphology. This study provides new insights into how environmental temperature modulates tissue adaptation and physiological homeostasis in mammals. Full article

Energy gels are widely used by athletes to maintain performance during endurance activities; however, their acidic composition may pose a risk to dental health. This study aimed to evaluate the pH of four commercial energy gels at different dilutions with artificial saliva and to assess the potential neutralizing effect of casein phosphopeptide–amorphous calcium phosphate (CPP–ACP). An in vitro experimental design was conducted using four commercial gels (FullGas Hydrogel, ENA Energy Gel, UltraTech Gel, and Maverick Race Gel). Serial dilutions with artificial saliva (1:2, 1:5, 1:7, and 1:10) were prepared, and pH was measured using indicator strips at 0, 15, and 30 min at 37 °C. The effect of CPP-ACP was evaluated in the 1:2 dilution. Undiluted gels showed highly acidic pH values ranging from 2.0 to 3.0. Dilutions of 1:2 and 1:5 remained significantly more acidic than artificial saliva (p < 0.001). From 1:7 dilution onward, pH values increased and approached salivary levels (approximately 7.0), with no significant differences compared with artificial saliva. The addition of CPP-ACP significantly increased pH in the 1:2 dilution (p < 0.05), although the effect was limited in more diluted conditions. These findings suggest that commercial energy gels may represent a source of acidic exposure under in vitro conditions, which could be relevant for dental health. Adequate dilution, particularly ≥1:7, was associated with a reduction in acidity under the experimental conditions tested, although its clinical relevance cannot be directly inferred, while CPP-ACP may provide a limited buffering effect under concentrated exposure conditions. Full article

Dynamic muscular endurance, the ability to lift a submaximal load until task failure, is a common measure in both cross-sectional and training studies. However, the repeatability of low-load muscular endurance in the knee extensors has not been well established. Establishing reliability metrics is essential to ensure that observed differences reflect true physiological changes rather than measurement error. The purpose of this study was to quantify the repeatability of low-load dynamic knee extensions performed to task failure. Forty healthy adults completed three visits, each consisting of one set of knee extensions at 20%, 30%, and 40% of one repetition maximum (1RM) to assess relative muscular endurance, and three sets at 20% 1RM on the contralateral leg to assess the impact of fatigue within a single session (fatigue curve). Intraclass correlation coefficients (ICCs), standard error of the measurement, and smallest detectable difference (SDD) were calculated. Repeatability ranged from moderate to excellent across conditions (ICC = 0.77–0.94). Lower loads and later sets demonstrated reduced repeatability compared with heavier loads and earlier sets. These results indicate that researchers and practitioners should consider load and fatigue curve effects in protocol design and SDDs when interpreting the meaningfulness of individual changes in knee extension muscular endurance. Full article

Recent evidence implicates the gut microbiota in muscle physiology and function via the gut–muscle axis, which portrays bidirectional communication between microbial colonies, their metabolites and muscle tissue. Age-related muscle decline, including sarcopenia and muscle atrophy, has been associated with shifts in gut microbiota composition and lower levels of microbial metabolites, such as short-chain fatty acids (SCFAs), thereby expanding muscle health research toward microbiota-based therapies. Postbiotics, defined as preparations of inanimate microorganisms and/or their components, are gaining attention as a novel approach to combating muscle decline through modulation of microbiota–host communication, yet a comprehensive review of this topic is currently lacking. Preclinical studies demonstrate that postbiotics may exert anabolic effects while attenuating catabolism, inflammation, and cellular senescence, with associated improvements in grip strength, endurance capacity, and muscle morphology. Although clinical evidence remains limited, available studies indicate that postbiotics may have beneficial effects on muscle strength, endurance, and overall physical performance in humans. By synthesizing recent preclinical and clinical evidence, this review addresses an important gap in the literature, offering a comprehensive and mechanistically informed perspective on the potential role of postbiotics in modulating muscle health, particularly in the context of sarcopenia- and atrophy-associated muscle phenotypes. Full article