Hybrid Dy-NFIS & RLS equalization for ZCC code in optical-CDMA over multi-mode optical fiber

For long haul coherent optical fiber communication systems, it is significant to precisely monitor the quality of transmission links and optical signals. The channel capacity beyond Shannon limit of Single-mode optical fiber (SMOF) is achieved with the help of Multi-mode optical fiber (MMOF), where the signal is multiplexed in different spatial modes. To increase single-mode transmission capacity and to avoid a foreseen “capacity crunch”, researchers have been motivated to employ MMOF as an alternative. Furthermore, different multiplexing techniques could be applied in MMOF to improve the communication system. One of these techniques is the Optical Code Division Multiple Access (Optical-CDMA), which simplifies and decentralizes network controls to improve spectral efficiency and information security increasing flexibility in bandwidth granularity. This technique also allows synchronous and simultaneous transmission medium to be shared by many users. However, during the propagation of the data over the MMOF based on Optical-CDMA, an inevitable encountered issue is pulse dispersion, nonlinearity and MAI due to mode coupling. Moreover, pulse dispersion, nonlinearity and MAI are significant aspects for the evaluation of the performance of high-speed MMOF communication systems based on Optical-CDMA. This work suggests a hybrid algorithm based on nonlinear algorithm (Dynamic evolving neural fuzzy inference (Dy-NFIS)) and linear algorithm (Recursive least squares (RLS)) equalization for ZCC code in Optical-CDMA over MMOF. Root mean squared error (RMSE), mean squared error (MSE) and Structural Similarity index (SSIM) are used to measure performance results

Dental health care providers’ concerns, perceived impact, and preparedness during the COVID-19 pandemic in Saudi Arabia

Background Dental health care providers (DHCPs)are at high risk of cross-infection during clinical practice therefore, the aim of the study was to evaluate the DHCPs Covid-19 related concerns, its perceived impact, and their preparedness in Saudi Arabia. Methods This cross-sectional study on DHCPs was carried out at five dental teaching hospitals/colleges in four provinces of Saudi Arabia from October to December 2020. A 35-item valid and reliable questionnaire was used to assess the concerns, perceived impact, and preparedness of DHCPs in the COVID-19 pandemic. Chi-square tests and logistic regression were used to compare parameters between the clinical and non-clinical staff. Results A total of 320 DHCPs participated in this study with proportion of clinical staff (57.5%) surpassing the non-clinical staff (42.5%). The clinical DHCPs felt greater odds of falling ill with COVID-19 than non-clinical workers (OR, 2.61) and willing to look for another job (OR, 3.50). The higher proportion in both groups was worried that people close to them would be at higher exposure risk (96.3%) however, slightly more clinical DHCPs were concerned for their children than a non-clinical worker (OR, 3.57). The clinical DHCPs have greater odds of worrying that people would avoid them and their family members because of their job (OR, 2.75). A higher proportion in both groups (75.0%, 63.2%) felt that they would feel stress at work. More non-clinical DHCPs (94.1%) had received training for infection control than clinical (94.1% vs 63.0%: OR 0.10). Similarly, more DHCPs in the nonclinical group received adequate personal protective equipment training (88.2%; OR, 0.48). Most participants practiced self-preparation such as buying masks and disinfection (94.4%, 96.9%). Conclusion The majority of DHCPs felt concerned about their risk of exposure and falling ill from infection and infecting friends/family. These concerns could potentially affect the working of DHCPs during this pandemic. Measures to improve protection for DHCPs, minimize psychological implications, and potential social stigmatization should be identified at the planning phase before any pandemic

Gingival biotypes and its relation to biologic width, alveolar bone thickness, dehiscence and fenestration in mandibular anterior region: A CBCT analysis study

Background: Gingival biotype and its relationship to biologic width and alveolar bone thickness may affect surgical periodontal therapy outcomes. Hence, it is vital to assess the gingival biotype prior to any of these treatments for its success. Aim: The study aims to compare the thick and thin gingival biotype in the mandibular anterior region concerning biologic width, buccal bone thickness, prevalence and distribution of dehiscence, and fenestration in lower anterior teeth. Materials and Methods: A total of 30 patients were selected for the study based on the inclusion and exclusion criteria. The Cone Beam Computed Tomography analysis was performed in the mandibular anterior area to assess gingival thickness (biotype), biologic width, buccal bone thickness, dehiscence, and fenestrations. The data were analyzed using SPSS version 26. An independent t-test was used to assess the relationship between the variables. Results: Our study identified an increased biologic width in the thick gingival biotype, a higher frequency of dehiscence in the thin gingival biotype than in the thick biotype, and a greater mean alveolar bone thickness in the thick biotype group. Conclusion: A statistical difference was not observed between the groups; however, the thick biotype showed better results than the thinner biotype for the periodontal parameters examined