Search

COVID-19 has affected people’s lives in different ways from reduced mobility and staying-at-home orders to other daily life routines. These changes have, in turn, affected the quality of life in urban environments including air quality and noise. The noise aspect, for example, suggests quieter environments due to fewer vehicles on streets, and less human activities. On the other hand, staying at home may cause more activities happening at the building level, i.e., more people in buildings may make more noise for neighbors. In order to understand this nexus, the study examines the noise complaints data in Dallas, USA. To do this, the study first compares the noise complaints after the COVID-19 intercourse and the same data period in 2019. Findings surprisingly show reduced noise complaints during the COVID-19 time frame by about 14% compared to the pre-COVID-19 period. The majority of this reduction occurred in and around the city center. In other words, the noise complaints seem more spatially dispersed at the outskirts of the city. Another finding that directs more detailed analyses, however, considers the massive reduction of ridership, traffic circulation, and building permits. This needs some other techniques for determining the sources for incommensurate noise complaints.

This paper presents optical solitons with the concatenation model having spatio-temporal and chromatic dispersions. This model can advantageously curtail the Internet bottleneck effect. Two integration schemes yield these solitons. By utilizing the multipliers approach, the conservation laws are also derived.

The parameter dynamics of super-sech and super-Gaussian pulses for the perturbed nonlinear Schrödinger’s equation with power-law nonlinearity is obtained in this article. The variational principle successfully recovers this dynamical system. The details of the variational principle with the implementation of the Euler–Lagrange’s equation to the nonlinear Schrödinger’s equation with power-law of nonlinearity described in this paper have not been previously reported.

Background: The aim of this study was to investigate the potential association between vitamin D deficiency and matrix metalloproteinase-9 (MMP-9) levels in gingival crevicular fluid (GCF) across various periodontal health and disease statuses., Methods: A total of 200 volunteers were divided into two groups according to serum vitamin D concentration (25(OH)D < 10 ng/mL and 25(OH)D ≥ 10 ng/mL). Periodontal health status was determined based on a full-mouth periodontal examination and radiographic evaluation. Participants in both groups were categorized according to periodontal diagnoses, encompassing periodontal health, gingivitis, and periodontitis. Following sampling, the MMP-9 levels in GCF were determined by the enzyme-linked immunosorbent assay (ELISA) method., Results: The GCF MMP-9 levels were found to be higher in individuals with serum 25(OH)D < 10 ng/mL, in both the healthy and gingivitis and periodontitis groups, compared to those with 25(OH)D ≥ 10 ng/mL. Nevertheless, a statistically significant distinction was observed exclusively within the gingivitis and periodontitis groups. Correlation analysis and robust regression analyses provided additional evidence supporting the predictive role of periodontal disease status and vitamin D concentration in local MMP-9 levels. These associations remained significant after adjusting for age and sex in robust regression analysis (p = 0.002). Furthermore, the inclusion of periodontal clinical parameters in the regression analysis revealed notable associations of clinical attachment loss with local MMP-9 levels, along with periodontal disease status and serum vitamin D concentration (p < 0.001)., Conclusion: The findings of our study suggest a potential mechanistic relationship between serum vitamin D levels and periodontitis., Plain Language Summary: Vitamin D deficiency is a widespread issue globally due to urban living, less outdoor time, seasonal changes, aging, and sunscreen use, leading to inadequate sun exposure. Low vitamin D levels are linked to several health problems, including hypertension, diabetes, heart diseases, and periodontal diseases, which affect the gums and bones around teeth and can cause tooth loss if untreated. Although the link between vitamin D and periodontal disease is unclear, it may involve the enzyme matrix metalloproteinase-9 (MMP-9). Our study examined 200 people, dividing them into two groups based on vitamin D levels. We assessed their gum health and measured MMP-9 levels in their gingival crevicular fluid, a liquid that seeps out from the tiny space between gums and teeth. We found that people with lower vitamin D levels had higher MMP-9 levels, especially those with gum disease. Our analysis showed that both vitamin D levels and gum health significantly impact MMP-9 levels, with gum health being the more influential factor. Maintaining good gum health and adequate vitamin D levels is crucial for managing MMP-9, an enzyme critical for tissue remodeling during healing and inflammation. However, excessive MMP may rapidly destroy periodontal tissues., (© 2024 The Author(s). Journal of Periodontology published by Wiley Periodicals LLC on behalf of American Academy of Periodontology.)

Introduction: To evaluate the manual dexterity of dentistry students and academicians when using a mirror according to increasing professional experience., Materials and Methods: The study included 72 subjects, grouped according to professional experience 5th year dentistry students (DS) accepted as no experience-academicians with 1-4 years experience (A5L)-academicians with ≥5 years experience (A5M). Direct and indirect visualisation using the mirror was evaluated with the completion times of the O'Connor Finger Dexterity Test., Results: The hand grip strength values of both left and right hand were found to be statistically significantly higher in all the males than in the females (p < .05). The indirect test times (ITT) using the mirror were significantly longer for males than for females (p = .001), and no significant difference was determined between the genders in the direct test times (DTT) (p > .05). For all the study participants, DTT shortened as professional experience increased (p < .05). In addition, the mean values of both DTT (p = .031) and ITT (p = .028) in the DS group were statistically significantly longer than the A5M group., Conclusion: With increasing professional experience, manual dexterity was determined to increase, and females were found to be more successful in the direct manual dexterity tests independently of the groups. The statistical significance between the DS and A5M groups, especially in the hand dexterity test with a mirror, shows the importance of experience. The study results demonstrated that professional manual dexterity in dentistry can be developed with increasing practical application., (© 2023 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)