Search Results (2,743)

High sound pressure level (SPL) acoustic sensing requires miniaturized microphones that can operate under large acoustic loading while maintaining mechanical linearity, sufficient sensing response, and broadband audio frequency behavior. This work targets high-SPL operation and numerically investigates a graphene piezoresistive MEMS microphone based on a membrane-supported beam–island diaphragm. The proposed structure retains a continuous membrane for acoustic load bearing, while the upper beam–island topology redirects deformation-induced strain toward beam root regions where graphene piezoresistors are placed. This design is intended to increase the local strain available for piezoresistive readout without simply relying on larger global diaphragm deflection. Finite-element analysis was used to optimize the diaphragm geometry and evaluate strain enhancement, pressure response linearity, modal behavior, and harmonic response. Under the 170 dB SPL reference condition, the optimized structure increases the peak structural strain from 47.83 με in a thickness-equivalent solid diaphragm to 562.53 με, achieving an approximately 11.8-fold enhancement in local sensing strain while maintaining a highly linear pressure response (R2 > 0.9999). Additionally, the results also show that the sensor exhibits a high first natural frequency of 64.07 kHz and a small response variation of approximately 0.94 dB within the 0–20 kHz target frequency range, indicating excellent dynamic stability and high-fidelity signal transduction characteristics. To connect the structural response with piezoresistive readout, first-order electromechanical output estimation was further performed using representative graphene gauge factors, quarter-bridge readout assumptions, contact resistance correction, and Johnson-noise-limited signal-to-noise ratio estimation. A ±5% geometric tolerance check further indicates that the membrane side length is the most fabrication-sensitive parameter, while the selected design remains generally robust except for reduced linearity margin under positive membrane side-length deviation. These results demonstrate the potential of the proposed graphene-based MEMS microphone for high-SPL broadband acoustic sensing applications in harsh and high-intensity acoustic environments. Full article

This study examines graphs that demonstrate Gallai’s property, particularly those in which for every prescribed set S of vertices with $\left|S\right|=j$ there exists a longest path or cycle that avoids that set. Such graphs are naturally fault-tolerant in the structural sense: if some vertices fail, there can still exist longest routes that bypass the failed vertices. Our main purpose is to construct explicit Gallai-type graphs that admit embeddings into a rigorously defined three-dimensional geometric adjacency structure derived from an icosahedral–tetrahedral polyhedral cell complex. We show that similar graphs may be found in three-dimensional structures obtained from a periodic polyhedral packing (cell complex) built from tetrahedral and icosahedral cells. Importantly, we do not claim a face-to-face tessellation of ${\mathbb{R}}^3$ by congruent regular icosahedra and tetrahedra; instead, we define a specific periodic cell complex ${\mathcal{IT}}^3$ and work in its associated adjacency graph $\mathsf{\Gamma }\left({\mathcal{IT}}^3\right)$. These geometric constructions expand lattice-based findings to a three-dimensional adjacency setting and provide new embeddings for Gallai-type graphs. Connections to AI systems are mentioned at the conceptual level. Full article

Mountain stream ecosystems are often considered among the least disturbed freshwater environments; however, increasing land-use pressures may affect their ecological integrity even under apparently high-water quality conditions. This study aimed to assess the relative influence of landscape, physicochemical, and hydromorphological factors on benthic macroinvertebrate communities in three sub-catchments (Ambroz, Jerte, and Tiétar) of the Sierra de Gredos (Central Spain). A total of 33 sampling sites were surveyed, and macroinvertebrate assemblages were analyzed in relation to environmental variables using partial Redundancy Analysis (pRDA) and variance partitioning. All sites were classified as having “Excellent” ecological status based on the Iberian Biological Monitoring Working Party (IBMWP) index. However, multivariate analyses revealed clear spatial patterns and responses to environmental gradients. Results indicated that catchment-scale landscape characteristics defined the pool of potential colonizers, while local physicochemical and hydromorphological conditions acted as secondary filters structuring macroinvertebrate assemblages. Landscape variables explained the largest fraction of variance in community structure (30.6%), followed by physicochemical parameters (29.0%) and hydromorphological indices (24.9%), with a significant shared component (16.5%) indicating interactions among drivers. Agricultural land use, particularly in the Jerte sub-catchment, was associated with shifts in community composition, favoring tolerant taxa such as Diptera, while sub-catchments dominated by natural vegetation supported higher richness of sensitive groups, including Ephemeroptera and Plecoptera. These findings highlight the importance of multi-scale processes in structuring mountain stream communities and reveal limitations of traditional biotic indices in detecting early ecological changes. The results support the integration of catchment-scale variables into ecological assessment frameworks and emphasize the need for preventive, basin-scale management strategies to maintain ecological integrity under increasing anthropogenic pressure. Full article

Patient-reported outcomes (PROs) are an integral component of contemporary oncology. They provide direct insight into symptom severity, treatment tolerability, and health-related quality of life. Despite their clinical relevance, routine implementation faces several hurdles. Key limitations include patient survey fatigue, challenges in real-time interpretation of complex symptom trajectories, and incomplete longitudinal data that limit reliable analysis. This narrative review summarizes recent advances (2020–2026) in applying artificial intelligence (AI) to structured questionnaires, including EORTC QLQ-C30, PROMIS, and PRO-CTCAE, as well as to unstructured clinical text. Machine learning and natural language processing may enhance the clinical utility of PROs through automated analysis, symptom extraction, and predictive modeling. Current studies suggest that AI-based approaches can support the prediction of symptom deterioration, treatment-related toxicity, and healthcare utilization, including unplanned hospitalizations and emergency department visits. Furthermore, NLP models can extract clinically meaningful information from free-text narratives. We also discuss emerging non-invasive digital biomarkers derived from speech and facial expressions. Multimodal approaches suggest that these features may provide complementary indicators of pain, fatigue, and affective state. Overall, AI has the potential to transform PROs from static assessment tools into dynamic clinical instruments. This shift may enable more continuous and proactive symptom monitoring and support the integration of multimodal patient data into oncology decision-making workflows. Full article

The mitigation of anthropogenic climate change caused by fossil fuel combustion is a critical global challenge that necessitates a transition to renewable energy systems. Bioethanol represents a major renewable fuel, but first-generation production relies on edible feedstocks, which raises concerns regarding food security. Consequently, research is shifting toward second-generation bioethanol produced from abundant non-edible lignocellulosic biomass sources. This review comprehensively examines the potential of Candida krusei (synonyms: Pichia kudriavzevii, Issatchenkia orientalis) to serve as an alternative biocatalyst for second-generation bioethanol production. Compared with the first-generation bioethanol-producing yeast Saccharomyces cerevisiae, C. krusei exhibits superior physiological traits, such as thermo, acid, and inhibitor tolerances, enabling the utilization of several lignocellulosic feedstocks. This review summarizes the taxonomic and physiological characteristics of C. krusei, describes case studies on bioethanol production, and discusses strategies for reducing production costs. Furthermore, the technical and biosafety challenges associated with the industrial deployment of C. krusei are critically examined, including xylose metabolism limitations, scale-up constraints, and the management of its opportunistic pathogenic nature. A life cycle assessment perspective suggests that the unique physiological properties of C. krusei contribute to reducing greenhouse gas emissions and energy consumption throughout the entire production process, from pretreatment to downstream ethanol recovery. Full article

Despite significant improvements in vehicle management efficiency achieved through the integration of VANET and Internet of Things technologies, Internet of Vehicles (IoV) networks remain vulnerable to cyberattacks. This is because the wireless data exchange channel in IoV has several vulnerabilities that are exploited to carry out cyberattacks. The article suggested using the symmetric block cipher GOST 34.12-2015 (SBCG) to combat a variety of cyberattacks. This cipher was chosen because it can be efficiently implemented on low-power platforms and offers high cryptographic strength and encryption speed. Furthermore, implementing SBCG in polynomial modular codes (PMCs) enables detection of encryption errors caused by faults in encoder/decoder operation. The scientific novelty of the proposed solution is that it is the first method to increase the fault tolerance of an SBCG encoder, enabling real-time, effective countermeasures against faults caused by both Differential Fault Analysis (DFA) attacks and natural faults. The originality of the solution lies in the integration of cryptographic theory and the theory of constructing correcting modular codes. The goal of this study is to improve the resilience of SBCG encryptors/decoders to faults by using polynomial modular codes. Imparting fault-tolerant properties to SBCG encryption systems implemented in PMC will enable them to effectively mitigate real-time faults arising from both Differential Fault Analysis (DFA) attacks and natural faults. Full article

Natural extracts derived from plants and algae are increasingly recognized for their ability to modulate plant growth and physiological processes due to their rich content of bioactive compounds. Depending on their composition and concentration, these extracts may act as biostimulants, enhancing germination, stress tolerance, and antioxidant activity, or may exhibit inhibitory effects. This study aimed to determine the effects of extracts from Ascophyllum nodosum, Fucus vesiculosus, and Sideritis scardica, prepared using different solvents, on germination parameters, early growth, chlorophyll content, chlorophyll a fluorescence parameters, secondary metabolite levels (phenolic compounds and flavonoids), and antioxidant activity in mung bean (Vigna radiata L.). The results showed that aqueous and hydroethanolic extracts were generally safe for germination, maintaining high germination capacity, whereas 10% ethanolic extracts exhibited pronounced inhibitory effects, reducing germination energy to as low as 8%. Secondary metabolism was markedly affected, particularly by S. scardica extracts, with dose-dependent changes observed in total phenolic and flavonoid contents. Despite these biochemical alterations, chlorophyll fluorescence parameters remained stable, indicating the absence of photoinhibitory stress. Overall, the results indicate that the biological activity of the extracts depends strongly on solvent type and concentration, which determine whether they act as biostimulants or inhibitors by modulating early growth, metabolism, and physiological status. These findings provide a basis for the development of optimized plant- and algae-based biostimulant formulations. Full article

Bone loss in the maxillofacial region arises from multiple causes, including periodontal disease, trauma, surgical procedures, infection, congenital anomalies, and cancer. Traditional treatment relies on bone grafting, either alone or in combination with biomaterials. Advances in tissue engineering have introduced synthetic or natural scaffolds to mimic the mineralized bone matrix. Natural scaffolds offer excellent biocompatibility and similarity to native tissue but often lack sufficient mechanical strength and exhibit poor degradation rates. Synthetic scaffolds provide tunable porosity and mechanical stability; however, their biological inertness makes them poor sources of osteogenic signaling. A key factor in the success of any scaffold is its interaction with the host immune system. Upon implantation, the innate immune response is initiated, with neutrophils and macrophages being the first cells to contact the scaffold. Macrophage polarization toward proinflammatory (M1) or anti-inflammatory (M2) phenotypes determines whether the microenvironment favors inflammation or remodeling. The adaptive immune response also plays a critical role: T and B lymphocytes may promote tolerance and integration through Th2/Treg pathways and antibody-mediated regulation, or they may trigger chronic inflammation and rejection through Th1/Th17 activation. This review examines the natural and synthetic materials used for bone remodeling and their biological properties. It then outlines the sequence of immune events occurring from the moment a scaffold is implanted to its potential integration or failure. Finally, this study highlights the relevance of cellular models and in vitro assays for the early evaluation of immunogenicity and biocompatibility, which are essential for optimizing scaffold design and improving outcomes in maxillofacial bone regeneration. Full article

Gloiopeltis tenax is a red seaweed containing diverse polysaccharides and bioactive compounds with potential functional applications in animal nutrition. However, information regarding its physiological and microbiome-associated effects in companion animals remains limited. The present study was designed as an exploratory nutritional intervention to evaluate physiological responses associated with dietary G. tenax supplementation in healthy adult dogs using an integrated framework including nutrient digestibility, glycan-degrading enzyme activity, fecal microbiome profiling, and serum metabolomics. Ten healthy adult dogs were assigned to two dietary groups receiving nutritionally balanced diets containing either Ulva sp. (CON) or G. tenax (GT) at 1% inclusion for 16 weeks under standardized feeding and housing conditions. Nutrient digestibility, fecal glycan-degrading enzyme activities, fecal microbiome composition, predicted microbial functional profiles, and serum metabolomic responses were evaluated. No significant differences were observed in nutrient digestibility, fecal score, or general health-related parameters between groups, suggesting acceptable tolerability of dietary G. tenax under the present experimental conditions. Relative abundances of several bacterial taxa differed between groups, and glycan-degrading enzyme activities showed directional changes associated with dietary treatment. PICRUSt2-based analyses suggested potential differences in predicted carbohydrate- and glycan-associated microbial functional tendencies between groups. Serum metabolomic analysis additionally revealed alterations in several amino acid- and carbohydrate-related metabolites associated with dietary intervention. Collectively, these findings provide preliminary insight into microbiome- and metabolome-associated responses to dietary G. tenax supplementation in dogs. Although limited by the exploratory nature and relatively small sample size of the present study, the integrated multi-omics approach applied here may contribute to the development of functional evaluation frameworks for companion animal dietary ingredients. Further studies with larger cohorts and expanded functional analyses are warranted. Full article

In this study, the stability, electronic, structural, and fracture toughness, and mechanical properties of the Half-Heusler(HH) alloys MnCoSb, MnCoAs, MnCoP, and MnNiSb were comprehensively investigated using first-principles calculations based on density functional theory (DFT). The calculated results reveal that all four alloys exhibit half-metallic characteristics, characterized by the presence of a substantial band gap in the spin-down channel. The phonon spectra and negative formation energies confirm that these alloys possess both dynamic and thermodynamic stability. The Born criteria further validate the structural stability in terms of mechanical properties. Three-dimensional representations of the Young’s modulus, bulk modulus, and shear modulus for the four alloys indicate that MnCoP exhibits the most pronounced anisotropy. The overall fracture toughness of the alloys ranges from 1.58 MPa·m^1/2 to 2.63 MPa·m^1/2, which falls within the typical range for half-metallic materials, albeit at the lower end, attributable to the relatively ductile nature of the four alloys. Although the two methods yield different absolute values, the explicit crack model (Method I) is considered more reliable for anisotropic systems because it directly simulates crack propagation and accounts for local relaxations, while the empirical formula (Method II) provides a useful reference for high-throughput screening. Among the alloys, MnCoSb demonstrates a superior mechanical performance, with K_IC values of 2.63 MPa·m^1/2 and 1.58 MPa·m^1/2 and brittleness indices M of 8.97 and 14.94, indicating excellent damage tolerance compared to the other three alloys. In contrast, MnCoP exhibits higher brittleness and lower mechanical reliability, with K_IC values of 2.00 MPa·m^1/2 and 1.63 MPa·m^1/2 and higher M values of 13.83 and 16.99. This study provides quantitative predictions of fracture toughness and establishes a relationship between microscopic and mechanical properties. These findings offer a theoretical foundation for the application of damage-tolerant HH alloys in fields such as spintronics and magnetism. Full article

Buildings in hot–humid climates experience increasing thermal stress due to urban heat islands and climate change, leading to greater reliance on air conditioning. Passive cooling is therefore a crucial low-carbon strategy for maintaining thermal comfort. This paper reviews thermal comfort ranges and passive-cooling techniques across Köppen–Geiger hot–humid climate classes. A two-stage approach was adopted: thermal comfort data from 35 field studies were analyzed by climate class and ventilation mode, while more than 70 application studies were qualitatively reviewed to assess mechanisms, performance, and climate suitability. The results indicate that occupants in hot–humid areas exhibit broad thermal tolerance, particularly in naturally ventilated buildings, with neutral temperatures ranging from 19.5 °C in humid subtropical climates to 36.3 °C in tropical savanna climates. Natural ventilation is the most widely applicable passive-cooling strategy, but its effectiveness depends on integration with climate-responsive measures. Ventilation, combined with solar protection and courtyards, is most effective in Af and Am climates, whereas shading, solar chimneys, evaporative cooling, night ventilation, thermal mass, and phase-change materials provide greater benefits in Aw, Cfa, and Cwa climates. However, no single strategy is sufficient across all climates. The review provides climate-specific guidance for designing low-carbon, thermally resilient buildings in hot–humid regions. Full article

Osmolytes, including proline, soluble sugars, and glycine betaine (GB), are essential for plant adaptation to environmental stress. They contribute to osmotic adjustment, membrane stabilization, and the protection of cellular functions in arid and saline habitats. This study investigated major osmolytes (mainly proline and soluble sugars) in native Qatari plant species in natural field conditions and their physiological adaptation strategies. Significant interspecific variation indicated diverse mechanisms of stress acclimation. Although proline accumulation was common, it did not consistently correlate with salinity tolerance, which suggests that its accumulation may reflect stress-induced metabolic imbalance and adaptation rather than being a reliable indicator of resistance. Plant species, including crops and native plants such as Avicennia marina, Halopeplis perfoliata, Limonium axillare, Tetraena qatarensis, and Ochradenus baccatus, are presented as examples supporting this pattern. In contrast, the relative balance between soluble sugars and proline indicates coordinated carbon–nitrogen regulation that supports osmotic homeostasis and growth in fluctuating environmental conditions. Halophytic species exhibited distinct osmolyte profiles that highlight the potential role of additional compatible solutes (particularly GB) in stress adaptation. However, its occurrence and functional significance in these species have been insufficiently characterized. Given the predominance of C₃ photosynthesis in Qatari flora, GB may also help mitigate photorespiratory stress in extreme conditions. The findings expand the current understanding of osmotic regulation in desert plants and highlight the potential of biotechnological approaches to enhance crop tolerance of harsh environments by manipulating compatible solutes. Full article

Cold stress is a critical abiotic factor that severely limits plant growth and agricultural productivity in subtropical regions. Poncirus trifoliata exhibits exceptional cold hardiness and is widely used as a rootstock in Citrus. However, the key genes and mechanisms conferring this resilience remain largely unexplored. Here, we characterized PtCOR8, a cold-induced gene isolated from P. trifoliata. Phylogenetic and subcellular localization analyses confirmed that PtCOR8 encodes a plasma membrane-localized protein belonging to the WCOR413 family. Functional validation revealed that heterologous overexpression of PtCOR8 in tomato significantly enhanced cold tolerance, concomitant with reduced malondialdehyde (MDA) content, elevated peroxidase (POD) activity, and upregulation of cold-responsive genes (e.g., CIN8). Notably, expression profiling of COR8 in 16 citrus accessions under natural overwintering conditions indicated a strong positive correlation between its expression level and cold tolerance of different genotypes. Transgenic tomato plants with PtCOR8 driven by its native promoter also presented enhanced cold tolerance, confirming that the native promoter is sufficient to drive functional expression under cold stress in the tomato system. Through promoter deletion and β-glucuronidase (GUS) staining experiments, the ATCT motif was further identified as a cis-acting element capable of mediating cold-induced promoter activity. Our findings uncover a dual-layered mechanism in which the PtCOR8 protein alleviates membrane lipid peroxidation and oxidative damage, while its transcription level is precisely modulated by a novel promoter regulatory mechanism, thereby improving freezing tolerance. This study provides important genetic insights and a valuable gene resource for cold-resistant citrus breeding. Full article

Acne vulgaris is a prevalent inflammatory disorder of the pilosebaceous unit involving follicular hyperkeratinization, altered sebum production, Cutibacterium acnes proliferation, microbiome imbalance, and immune activation. Although antibiotics, retinoids, benzoyl peroxide, and keratolytic agents remain central to clinical management, their long-term use may be limited by irritation, recurrence, adherence issues, and increasing antimicrobial resistance. This narrative review critically evaluates the dermatological relevance of Melaleuca alternifolia tea tree essential oil (TTEO), Mentha piperita peppermint essential oil (PPEO), and polyhydroxy acids (PHAs), as well as their incorporation into biopolymeric delivery systems for acne-oriented topical applications. Following SANRA principles, evidence from clinical, preclinical, ex vivo, and in vitro studies was synthesized, with emphasis on antimicrobial activity, inflammatory modulation, keratolytic and barrier-supportive effects, formulation stability, and release behavior. TTEO shows the strongest clinical support among the reviewed natural bioactives, including reductions in lesion counts and acne severity when applied as conventional or nanoemulsion-based formulations. PPEO is mainly supported by experimental evidence, particularly antimicrobial activity against acne-associated microorganisms, anti-inflammatory potential, and menthol-related neurocutaneous effects, whereas acne-specific clinical validation remains limited. PHAs, particularly gluconolactone, are better supported for barrier improvement, hydration, tolerability, and seboregulation than for direct acne lesion reduction. Hydrogels, electrospun nanofibers, polymeric films, nanoencapsulation systems, and controlled-release platforms may improve local retention, protect volatile or irritation-prone compounds, and modulate active release at the skin surface. However, most biopolymeric platforms still rely on early-stage or indirect dermatological evidence. Overall, biopolymeric delivery systems offer a rational formulation strategy to improve the stability, tolerability, and localized action of selected acne-relevant bioactives, but their clinical translation requires standardized composition, reproducible fabrication, skin-relevant release assays, safety assessment, and controlled human studies. Full article

Cold stress is a major environmental constraint limiting the growth, physiological performance, and productivity of African marigold (Tagetes erecta L.) under open-field conditions. This study evaluated the comparative effectiveness of salicylic acid (SA), silicon (Si), and methyl jasmonate (MeJA) in alleviating cold-induced damage and enhancing stress tolerance. Field experiments were conducted under naturally occurring cold stress using foliar applications of SA (0, 0.1, 0.5, and 1 mM), Si (0, 1, 5, and 10 mM), and MeJA (0, 10, and 50 µM) in a complete randomized block design with three replications. Moderate concentrations of all three regulators significantly (p < 0.05) improved plant growth and physiological stability relative to untreated controls. Salicylic acid at 0.5 mM produced the most consistent protective response, increasing biomass accumulation, chlorophyll content, and relative water content while reducing membrane damage, as indicated by a 42.3% decrease in leaf electrolyte leakage at 2 °C. Silicon at 10 mM enhanced membrane integrity, plant water status, and vegetative growth under low-temperature conditions, while methyl jasmonate at 10 µM mitigated cold-induced membrane damage and improved physiological tolerance, whereas higher concentrations (50 µM) were less effective. At their optimal doses, SA, Si, and MeJA increased plant dry mass by 39.7%, 30.1%, and 38.5%, respectively. Correlation analysis confirmed these results, revealing strong positive relationships among growth, chlorophyll, and relative water content. Conversely, electrolyte leakage was negatively correlated with biomass and water status, identifying membrane stability as a key determinant of cold tolerance. Overall, 0.5 mM SA, 5–10 mM Si, and 10 μM MeJA improved growth and key physiological responses in African marigold under cold stress under field conditions. Future studies should integrate mechanistic and economic analyses to refine growth-regulator-based cold-stress management strategies. Full article