In this paper we prove the existence of solution for a class of degenerate hyperbolic equations defined in whole space RN. Using some integral estimates we also prove a stability result for the problem. Finally, we also prove a blow-up result when the initial data satisfies an appropriate assumption. The main operator of the equation involves the so called Grushin operator and main goal of this paper is to introduce a new set of mathematical problems in the context of stability and blow-up results.
In this paper we study of a coupled thermoelastic system with viscoelastic damping term and Wentzell boundary conditions. We prove the existence as well as the stability of the energy associated to the problem. To prove the existence of solution we use semigroup theory and the stability is proved by multipliers techniques. The main goal is to bring the viscoelastic damping into the discussion concerning thermoelastic systems with Wentzell boundary conditions.
Urban air pollution remains a major environmental health challenge, yet longitudinal evidence linking particulate matter exposure to genotoxic biomarkers across contrasting climatic conditions remains limited. This study examined the association between particulate matter exposure, climatic season, and chromosomal damage in urban workers from Uberl & acirc;ndia, Brazil. A prospective repeated-measures panel study was conducted with 238 male participants who completed four sampling campaigns spanning rainy and dry seasons, including 116 street vendors working in the central urban area and 122 formal indoor vendors working in a reference area. Ambient PM1, PM2.5, and PM10 concentrations were monitored at seven fixed monitoring points, and genotoxic damage was assessed using the micronucleus (MN) assay in exfoliated buccal mucosa cells. Particulate matter concentrations varied significantly across campaigns (p < 0.001) and were consistently higher in the central urban work environments. MN frequency also showed significant temporal variation and was consistently higher among street vendors across all campaigns (p < 0.05), whereas binucleated cell frequency showed no significant temporal variation. In multivariable Poisson generalized estimating equation models accounting for repeated measurements and spatial heterogeneity, higher PM2.5 concentrations were positively associated with MN frequency during both the rainy season (IRR = 1.024 per 1 mu g/m(3) increase; 95% CI: 1.013-1.034) and the dry season (IRR = 1.026; 95% CI: 1.019-1.034). The PM2.5 x season interaction was not statistically significant (p = 0.378), providing no evidence that climatic season modified the association between PM2.5 and MN frequency. These findings demonstrate a consistent positive association between ambient PM2.5 concentrations and chromosomal damage across contrasting climatic conditions, alongside marked differences in particulate exposure and MN frequency between urban occupational environments. Integrating environmental monitoring with longitudinal human biomonitoring may provide a useful framework for urban environmental health surveillance.
Calcium (Ca²⁺) acts as a second messenger in bacterial stress responses. In Caulobacter vibrioides, the cabp gene encodes a previously uncharacterized calcium-binding protein (CaBP). In silico analysis predicted a 133-aa protein with three EF-hand motifs and an N-terminal Sec signal peptide. Consistently, CaBP exhibited a Ca²⁺-dependent mobility shift and was localized to the periplasm in a SecA-dependent manner. Transcriptional analyses revealed a non-canonical organization in which the sigV promoter lies within the cabp coding sequence, although both genes are independently transcribed. Deletion of cabp increased biomass and stationary-phase survival. Expression analyses showed that SigmaV modulates cabp, while CaBP positively affects sigV expression, forming a Ca²⁺ and pH-responsive regulatory loop. Both genes were induced by acid stress and calcium limitation. The mutant displayed altered cell asymmetry and increased extracellular matrix production. These findings identify for the first time that CaBP as a periplasmic EF-hand calcium sensor linking ionic and pH signals to SigmaV-dependent stress regulation.
To evaluate longitudinal changes in oral health–related quality of life (OHRQoL), pain, and mandibular function over 12 months after temporomandibular joint (TMJ) disc repositioning with mini-anchor fixation in women with refractory bilateral disc displacement without reduction (DDwoR). In this prospective cohort study, 34 women with bilateral DDwoR confirmed by Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) and magnetic resonance imaging (MRI), refractory to at least 6 months of conservative therapy, were assessed at baseline (T0), 1 month (T1), and 12 months (T2). Outcomes included the Oral Health Impact Profile-14 (OHIP-14), visual analog scale for pain (VAS-P), Helkimo Clinical Dysfunction Index (DI), and mandibular mobility measurements. Longitudinal changes were analyzed using repeated-measures ANOVA and linear mixed-effects models. Pain (VAS-P) decreased from 7.6 to 0.7, OHIP-14 from 29.4 to 7.0, and DI from 4.1 to 1.4 by 12 months (all p < 0.001). Reductions in OHIP-14 and VAS-P exceeded the predefined MCIDs (OHIP-14, ≥ 4.0 points; VAS-P, ≥ 2.0 points on the 0–10 scale). Mandibular mobility also improved significantly over time. Age-group analyses were exploratory; although an overall time × age interaction was observed for OHIP-14, no significant between-group differences were found at postoperative time points. TMJ disc repositioning with mini-anchor fixation was associated with significant improvements in OHRQoL, pain, and function in women with refractory bilateral DDwoR over 12 months. Not applicable.
