Search Results (1,229)

Gypsum-based fire protection relies on thermally activated dehydration, where chemically bound water is released and evaporated, thereby providing an endothermic heat sink that delays heat penetration through assemblies. In parallel, inorganic hydrated salts are increasingly used as flame-retardant additives in gypsum-based systems to enhance heat absorption over specific temperature ranges. Fire simulation tools and performance-based fire engineering approaches require reliable kinetic data and reaction enthalpies that can be implemented as coupled thermal–chemical source terms. However, additive-specific kinetic datasets remain limited, particularly under restricted vapor exchange conditions representative of porous construction materials. This work investigates the thermal decomposition behavior and dehydration kinetics of Aluminum Trihydrate (Al(OH)₃, ATH), Magnesium Hydroxide (Mg(OH)₂, MDH), Calcium Aluminate Sulfate (3CaO·Al₂O₃·3CaSO₄·32H₂O, CAS), and Magnesium Sulfate Heptahydrate (MgSO₄·7H₂O, ESM) with emphasis on vapor-restricted conditions representative of confined porous systems. Differential scanning calorimetry (DSC) experiments were conducted at three heating rates (2, 10, and 20 K/min for MDH, CAS and ESM and 20, 40 and 60 K/min for GB-ATH) up to 600 °C using pinhole crucibles to simulate autogenous vapor pressure. The thermal analysis indicates that ATH and MDH exhibit predominantly single-step dehydration behavior, while ESM shows a complex multi-step mechanism. Although CAS presents a single dominant thermal peak in the DSC signal, the isoconversional analysis reveals a multi-stage reaction behavior, demonstrating that peak-based interpretation alone may be insufficient for such systems. Kinetic parameters were determined using both model-free (Starink) and model-fitting approaches in accordance with the recommendations of the Kinetics Committee of the International Confederation for Thermal Analysis and Calorimetry (ICTAC). All reactions were consistently described using the Avrami–Erofeev model as an effective phenomenological representation of the conversion behavior. The extracted kinetic triplets were validated through numerical simulations, showing good agreement with experimental conversion and reaction rate data. The resulting kinetic parameters and dehydration enthalpies provide a physically consistent dataset for the description of dehydration processes under restricted vapor exchange. These results support the development of thermochemical models for gypsum-based systems; however, their transferability to full-scale assemblies remains subject to validation under coupled heat- and mass-transfer conditions. Full article

Treatment of postsurgical osteosarcoma remains one of the major challenges in orthopedic clinics. Conventional implants often fail to address complex pathological issues, including irregular bone defects, residual tumor cells, and delayed bone regeneration. Herein, this study reports a multifunctional shape-memory polyurethane (SMPU)/manganese dioxide (MnO₂) composite that provides adaptive support, antitumor activity, and osteogenic bioactivity. SMPU was synthesized by introducing 1,4-butanediol (BDO) and dimethylolpropionic acid (DMPA) as chain extenders at a specific ratio. Commercial MnO₂ nanoparticles were incorporated as both a photothermal agent and a bioactive component to achieve multifunctionality. As designed, a coordination system was formed between the polymer chains and MnO₂ nanoparticles within the composites. The influence of MnO₂ content was systematically investigated. Although increasing MnO₂ amounts improved photothermal and mechanical performance, excessive incorporation adversely affected the molecular structure and compromised the composite’s biocompatibility. By adjusting the MnO₂ content, the composites were demonstrated to possess robust mechanical performance, good shape-memory behavior, and controllable Mn²⁺ release. Additionally, the composites exhibited tunable photothermal performance under near-infrared (NIR) irradiation. Furthermore, in vitro studies confirmed that the composites containing 4 wt% MnO₂ could eliminate tumor cells via photothermal effects and promote the osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (hBMSCs). Overall, the SMPU/MnO₂ composites had superior multifunction for treating irregular bone defects following bone tumor surgery. Full article

In this study, a composite powder explosion suppressant (MVTS–NaHCO₃) was prepared via the wet coating method of the solution–crystallization (WCSC) process, using modified vanadium–titanium slag (VTS) as the carrier and NaHCO₃ as the active suppressive component. A 20 L spherical explosion apparatus and a transparent pipeline explosion propagation test system were employed to investigate the effects of the composite powder explosion suppressant with different mass fractions (0%, 10%, 20%, 30%, 40%, 50%) on the explosion pressure and micro-mechanism of polyacrylonitrile (PAN) dust. The experimental results indicated that the MVTS–NaHCO₃ composite powder exhibited a significant suppression effect on PAN dust explosions. In the confined 20 L vessel, complete suppression was achieved when the mass fraction of the composite powder explosion suppressant exceeded 30%, with a maximum explosion pressure reduction of 53.2%. In the semi-open pipeline, 40% composite powder explosion suppressant reduced the maximum explosion pressure to 0.08 MPa (a reduction rate of 82.6%), and complete suppression was achieved at a mass fraction of 50%. Microstructural analysis revealed that the suppression performance of the composite powder explosion suppressant is attributed to the synergetic effects of physical and chemical mechanisms. Physically, NaHCO₃ decomposes endothermically (100 kJ/mol), releasing CO₂ and H₂O and thereby diluting the oxygen concentration, while the porous structure of MVTS enhances dispersibility. Chemically, the hydroxyl groups on the surface of MVTS bond with NaHCO₃, delaying its decomposition, while metal hydroxides (e.g., Al(OH)₃) decompose thermally to form Al₂O₃, which adsorbs and quenches free radicals (e.g., ·OH, ·H), thereby inhibiting chain reactions. This study provides new insights for the resource utilization of VTS and the prevention and control of industrial dust explosions. The findings have important reference value for optimizing explosion suppressant formulations and improving the intrinsic safety. Full article

Background: Campylobacter jejuni, a leading foodborne pathogen in poultry, relies heavily on iron for survival and colonizes the gastrointestinal tract (GIT). Iron supplementation in poultry diets can inadvertently promote pathogen growth, particularly when excess or poorly absorbed iron accumulates in the lower GIT. Encapsulated iron products, such as SQM^® Iron, offer a controlled-release mechanism that may mitigate this risk by reducing iron availability to microbes. Objective: This study evaluated the effects of free (FeSO₄) versus polysaccharide–iron complex (PIC) on C. jejuni growth under iron-limited conditions, hypothesizing that encapsulated iron would support slower and more limited bacterial proliferation due to delayed iron release. Methods: Growth kinetics of C. jejuni ATCC 700819 were assessed in chelated Mueller–Hinton broth supplemented with three iron concentrations (10, 20, and 50 ppm) of FeSO₄, PIC, or PIC matrix without iron. Optical density was measured every 20 min over 48 h under microaerophilic conditions. Maximum growth rate (µmax) and carrying capacity (K) were derived using non-linear curve modeling. ANOVA evaluated statistical significance with Tukey’s HSD post hoc comparisons. Results: Free iron (FeSO₄) consistently supported the highest µmax and K values across both trials, indicating rapid and robust C. jejuni proliferation. The effect of encapsulated iron was variable: at higher concentrations (50 ppm) it approached FeSO₄ performance, but at lower concentrations (10 ppm) its effect differed markedly between trials, sometimes supporting growth comparable to free iron and sometimes supporting substantially slower growth. The PIC matrix alone did not promote growth. These variable results indicate that the relationship between encapsulated iron and C. jejuni proliferation is complex and concentration-dependent. Conclusions: Free iron consistently promotes robust C. jejuni growth due to immediate bioavailability. The impact of encapsulated iron on C. jejuni proliferation is nuanced and variable, particularly at lower concentrations, suggesting its role in pathogen control is not straightforward and requires further investigation under controlled conditions. Furthermore, in vivo research is warranted to validate its utility in poultry pathogen management strategies. Full article

Hypersensitivity reactions to iodinated contrast media (ICM) are traditionally categorized as immediate or delayed reactions, involving IgE-mediated pathways, non–IgE-dependent mast cell or complement activation, or T cell–mediated immune mechanisms. However, we observed that some individuals develop systemic inflammatory responses that do not fit these established categories. We describe here a case series of three patients who developed cytokine release syndrome (CRS)-like reactions following iodinated contrast administration, which were initially difficult to distinguish from sepsis and were only recognized after recurrent episodes. Clinical presentation, laboratory findings, cytokine profiles, allergy investigations, and treatment outcomes were reviewed. All patients developed fever, rigors, and hypotension within 5 to 70 h after exposure, accompanied by leukocytosis and markedly elevated inflammatory markers despite negative microbiological investigations. Serum tryptase levels remained within the normal range with no significant rise, while cytokine analyses demonstrated elevations of pro-inflammatory interleukin-6 and other cytokines in patients 1 and 3 where samples were available. Standard corticosteroid premedication did not prevent recurrence, and one patient developed systemic symptoms following intradermal testing. All patients improved with high-dose systemic corticosteroids and supportive care. These findings suggest that ICM may induce a cytokine-mediated inflammatory phenotype distinct from classical hypersensitivity reactions, highlighting the importance of early clinical recognition to guide diagnosis and management. Full article

The building-integrated photovoltaic (BIPV) system has advantages in construction and energy, but due to the use of flammable polymer packaging materials, it introduces complex fire safety-related challenges. Although polymer backboards are traditionally considered to be the main combustible components in photovoltaic modules, recent studies have shown that ethylene–vinyl acetate (EVA) packaging materials play a key role in the development of fires. This study investigated the fire behavior, optical properties and system-level fire effects of montmorillonite (MMT) nano-clay-modified EVA packaging materials. Through the 50 kW/m² conical calorimeter test, optical transmittance measurement and the accelerated aging test, pure EVA and EVA containing 3% MMT were evaluated, and the measured fire parameters were further incorporated into the simplified BIPV cavity fire model. The results show that MMT modification reduces the peak heat release rate of EVA by about 30%, delays the ignition time, and increases the formation of carbides, while maintaining the optical transmittance of more than 88%. At the system level, the reduction in heat release leads to a decrease in the cavity temperature and delays the ignition of adjacent insulation materials. These findings establish a direct link between material-level fire behavior and the fire performance of BIPV systems, indicating that nano-clay-modified EVA is a feasible strategy that can improve the fire safety of BIPV systems integrated into the facade without compromising optical or durability requirements. Full article

Background/Objectives: This study aimed to develop bilayer tablets using hot-melt pneumatic extrusion (HMPE)-based 3D printing for the integrated treatment of allergic rhinitis and asthma. The formulation combined levocetirizine dihydrochloride (immediate release) and montelukast sodium (delayed release) within a single dosage form to provide a sequential-release formulation strategy relevant to the intended pharmacological roles of the two drugs. Distinct polymer matrices were selected for each drug layer to ensure mechanical robustness, stability, and appropriate release characteristics. Methods: The printed tablets were systematically characterized by mechanical testing, differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), and in vitro dissolution. Drug content uniformity was evaluated in accordance with USP <905>. Results: The tablets satisfied USP standards for content uniformity and exhibited sufficient mechanical strength for handling and packaging. DSC and PXRD analyses indicated amorphization of levocetirizine within the polymer matrix, while the amorphous state of the raw montelukast used in this study was retained after printing. In vitro dissolution tests demonstrated immediate release of levocetirizine in acidic medium (pH 1.2) and delayed release of montelukast at intestinal pH (6.8), thereby achieving the intended dual-phase release profile. Conclusions: These findings demonstrate the feasibility of fabricating an HMPE-based 3D-printed bilayer tablet integrating immediate-release levocetirizine and delayed-release montelukast, with reproducible dual-phase release and drug-specific solid-state and performance characteristics within a single oral dosage form. Full article

The aim of this study was to evaluate the effects of a gonadotropin-releasing hormone analogue (GnRHa), administered through injections or with sustained-release implants, on spermiation and sperm quality in thicklip grey mullet, Chelon labrosus. Male broodstock transferred from extensive lagoons were randomly allocated to three treatment groups: (a) weekly saline injections (Saline-INJ), (b) weekly GnRHa injections (10 μg kg⁻¹ bw; GnRHa-INJ), and (c) a single GnRHa EVAc implant (50 μg kg⁻¹ bw; GnRHa-IMP). Males were maintained with females under the same treatment protocols and allowed to spawn. Sperm condition, density, motility, duration of motility, and androgen levels were evaluated weekly at five sampling points (Days 0, 7, 14, 21, and 28). All males exhibited complete spermiation during the first two weeks (Days 0 and 7), followed by a gradual decline throughout the rest of the study (Days 14 and 21). This pattern of decline was not as evident in the groups treated with GnRHa, especially in the GnRHa-INJ group. Sperm density, motility, and motility duration varied strongly over time; however, no significant differences were observed among treatments. GnRHa treatment prolonged the spermiation period and delayed its seasonal decline without significantly altering sperm quality. These results may enable more frequent sperm collection and greater sperm availability, as inferred from the spermiation condition (SCI) and qualitative observations. Full article

Aging is associated with disturbances in brain energy metabolism, mitochondrial dysfunction, and increased oxidative stress, all of which increase neuronal vulnerability and contribute to the development of neurodegenerative disorders. Growing evidence indicates that physical exercise exerts neuroprotective effects through the release of exerkines–exercise-induced signaling molecules that mediate communication between peripheral tissues and the brain. Among them, irisin, a proteolytic cleavage product of the membrane protein FNDC5, has emerged as an important mediator of the muscle–brain axis. This review summarizes current knowledge on the molecular mechanisms underlying irisin activity in the central nervous system, with particular emphasis on the AMPK–PGC-1α–FNDC5/BDNF signaling axis, rapid receptor-mediated pathways involving the cAMP/PKA/CREB and ERK/CREB cascades, and the regulation of mitochondrial homeostasis, including biogenesis, dynamics, autophagy, and mitophagy. Experimental studies suggest that irisin may improve neuroplasticity, neuronal survival, mitochondrial function, and reduce oxidative stress, thereby alleviating cognitive deficits in models of aging and neurodegeneration. Although the precise receptor mechanisms and intracellular signaling events remain incompletely understood, accumulating evidence identifies irisin as a promising therapeutic target linking metabolic adaptation with neuroprotection. Further investigation of irisin-dependent pathways may facilitate the development of novel strategies aimed at preserving brain function and delaying the progression of age-related neurodegenerative diseases. Full article

As the boundary between indoor and outdoor spaces, the heat flux of a building envelope is a crucial factor influencing the indoor thermal environment and human thermal comfort, and also an important indicator reflecting the impact of outdoor meteorological factors on the indoor environment. In scenarios involving rapid assessment of existing buildings and engineering projects, the dynamic thermal performance of the building envelope are often affected by factors such as outdoor weather fluctuations, window–wall coupling, wall heat storage, and thermal bridging. To address this issue, this study proposes a dynamic heat flux calculation method that accounts for hysteresis. Simultaneously, the heat conduction equation of the implicit finite difference method (IFDM) and boundary conditions based on wall energy balance are used to optimize the wall surface temperature. An adaptive step size control strategy (Runge–Kutta–Fehlberg) is introduced in the time step setting. Results show that the heat flux R² of the proposed dynamic heat flux calculation method is 0.9207, and the optimized R² is 0.9435, both within an acceptable range for engineering applications. Studies have shown that the simplified framework derived from the heat flux analysis of building envelopes retains the characteristics of wall heat storage and delayed heat release, while effectively solving the window–wall coupling problem and significantly reducing the reliance on computationally expensive numerical methods. This method therefore provides an efficient and scalable technical pathway for thermal performance assessment and energy-retrofit decision support for existing building envelopes. Full article

We previously demonstrated that human herpesvirus 6A infects papillary thyroid cancer cells (BCPAP), inducing molecular changes compatible with a tumor-promoting phenotype, including increased expression of R273H mutant TP53 (mutp53), upregulation of c-Myc, and enhanced secretion of IL-6. To investigate whether and how epigenetic mechanisms contribute to these virus-induced effects, we examined the histone methyltransferase EZH2, a key regulator of chromatin repression frequently altered in cancer. HHV-6A infection reduced EZH2 expression and global H3K27me3 levels. Pharmacological inhibition of EZH2 using DS-3201 reproduced some of the molecular effects of viral infection, including increased mutp53 stability. Both viral infection and EZH2 inhibition induced delayed upregulation of SIRT1, which mediated deacetylation-dependent stabilization of mutp53 while reducing c-Myc expression. Indeed, the inhibition of SIRT1 with EX-527 reversed mutp53 accumulation but restored c-Myc expression and increased extracellular IL-6 release. This drug also reduced cell survival, suggesting that SIRT1 supports cellular adaptation to oncogenic stress triggered by EZH2 loss. Overall, our findings identify an epigenetic axis in which the HHV-6A-mediated downregulation of EZH2 induces SIRT1, regulating mutp53 stability and c-Myc expression and reshaping inflammatory signaling to maintain cell viability. These results establish a mechanistic link between viral infection, epigenetic remodeling, and oncogenic dependency. They also suggest that targeting IL-6 signaling could represent a therapeutic vulnerability in HHV-6A-associated thyroid cancer, particularly in combination with SIRT1 inhibitors. Full article

Timely assessment of macroeconomic conditions is essential because official gross domestic product (GDP) statistics are released with substantial delays and are often revised. This study examines whether high-frequency highway traffic volumes, disaggregated by vehicle type, improve short-term GDP nowcasting in the Republic of Korea. Using nationwide expressway traffic data from 328 toll plazas over the period from September 2008 to September 2025, we integrate traffic series with conventional macroeconomic indicators into a mixed-frequency dynamic factor model and evaluate pseudo-real-time nowcasting performance against official quarterly GDP releases. Time-series diagnostics indicate that traffic volumes contain short-horizon predictive information for GDP and satisfy stationarity requirements after appropriate transformation. In the full evaluation sample, the macro-only benchmark records an RMSE of 1.0258 and an MAE of 0.8716. Adding aggregated traffic changes these metrics only marginally (RMSE = 1.0269, MAE = 0.8696), whereas the model augmented with the heaviest freight class (Vehicle Type 6) performs best, lowering RMSE to 1.0179 and MAE to 0.8652. During the COVID-19 period, forecast accuracy deteriorates across specifications: aggregated traffic increases RMSE and MAE to 1.3456 and 1.2096 relative to the macro-only benchmark (RMSE = 1.3082, MAE = 1.2020), while Vehicle Type 6 lowers MAE to 1.1683 but still records a higher RMSE of 1.3198. These findings show that aggregate mobility measures add limited value, whereas freight-oriented vehicle-type disaggregation provides the most informative highway traffic signal for real-time GDP nowcasting. Full article

This paper presents an integrated mathematical model to improve the safety and operational efficiency of train traffic in centralised railway dispatching systems. The proposed approach combines the alternative graph model with a Mealy automaton to synchronously address route planning, delay minimisation, and strict compliance with safety requirements. Formal control theory based on finite-state automata is employed to describe routing logic and signal control through state transitions, while the alternative graph model represents scheduling constraints and resource conflicts. To enhance real-time adaptability, a tabu search algorithm is implemented for train schedule optimisation, enabling dynamic rescheduling under changing operational conditions. The mathematical formulation incorporates blocking time parameters, a system of discrete constraints, and automaton-based safety conditions governing train movements and route authorisation. The integrated model explicitly formalises the processes of block section occupation and release, ensuring consistency between control logic and scheduling decisions. Practical testing and computational experiments demonstrate that the proposed approach effectively reduces train delays, improves the reliability of dispatch control, and increases system resilience to dynamic disturbances. The results confirm that the developed model can be implemented within existing centralised dispatching infrastructures without requiring a complete system overhaul. Overall, the proposed framework expands the functional capabilities of centralised dispatch systems by enabling efficient schedule generation, minimising the propagation of delays, and ensuring reliable command exchange between central control posts and field-level railway infrastructure. Full article

Drug-resistant tuberculosis (DR-TB) represents a major public health threat, particularly in the prisons of Latin America and the Caribbean, where rates are up to 40 times higher than those observed in the general population. These facilities act as community amplifiers due to overcrowding, poor ventilation, diagnostic delays, and treatment discontinuity. This study offers a critical reflection on the magnitude, determinants, and implications of DR-TB in regional penitentiary contexts. A reflective analytical review was conducted in PubMed, Scopus, Web of Science, SciELO, and LILACS, complemented by WHO and PAHO reports, prioritising studies from 2019 to 2024. The findings reveal MDR-TB and pre-extensively drug-resistant (pre-XDR) outbreaks in Peru, Paraguay, and the Dominican Republic, as well as community transmission linked to prisons in Brazil and Colombia. Persistent gaps remain in systematic screening, drug susceptibility testing coverage, and post-release follow-up. Scientific production continues to be uneven and predominantly biomedical, with limited consideration of social and human rights determinants. DR-TB in prisons reflects the structural deficiencies of health and justice systems; its control requires intersectoral policies, genomic surveillance, and strategies that ensure early diagnosis, treatment continuity, and dignified detention conditions. Full article

Puberty is a neuroendocrine process required for sexual maturity; it is regulated by the hypothalamic–hypophysis–gonadal (HHG) axis. Kisspeptin (KISS1) plays a vital role in activating this axis by stimulating the secretion of gonadotropin-releasing hormone (GnRH). Cadmium (Cd) exposure disrupts KISS1 signaling in female rodents; its effects on hypothalamic gene expression during male puberty remain poorly understood. This study investigated the effects of Cd exposure on hypothalamic Kiss1, Kiss1r, and Gnrh1 expression, preputial separation (PS) as a marker of pubertal onset, testosterone levels, Cd concentration, and total antioxidant capacity (TAC) in the serum and hypothalamus of pubertal male Wistar rats. Animals received once a week intraperitoneal injection of CdCl₂ (1 mg/Kg body weight/100 µL) or saline (100 µL) and were euthanized on postnatal day (PND) 35 or 49. Cd exposure reduced serum testosterone levels and TAC. Also, pubertal onset was delayed. At PND 35, Cd decreased hypothalamic Kiss1 expression, whereas at PND 49, it reduced Kiss1r and Gnrh1 expression. These results suggest that Cd alters hypothalamic gene expression, which may contribute to delayed puberty and impaired sexual maturity. Our findings suggest the vulnerability of puberty to exposure to Cd, acting as an endocrine disruptor and neurotoxicant, with alterations for male reproductive maturity. Full article