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Haia Mohammed Kamihan Alenazi, Mohammad Abdul Baseer, Osamah Mohammed AlMugeiren, Navin Anand Ingle Preventive Dentistry Department, College of Medicine and Dentistry, Riyadh Elm University, Riyadh, Saudi ArabiaCorrespondence: Mohammad Abdul Baseer, Preventive Dentistry Department, College of Medicine and Dentistry, Riyadh Elm University, P.Box 84891, Riyadh, 11681, Saudi Arabia, Email ma_baseer@riyadh.edu.saObjective: This study aimed to assess and compare the salivary secretion, pH, and buffer capacity between COVID-19 vaccinated and unvaccinated child patients visiting the clinics of private university dental hospitals in Riyadh, Saudi Arabia.Methods: This is the first comparative assessment of salivary parameters between unvaccinated and COVID-19-vaccinated child patients. The study sample comprised COVID-19 unvaccinated (n = 66) and vaccinated (n = 66) pediatric dental patients aged 4– 12 years seeking dental care in clinics of private university hospitals. Paraffin-stimulated saliva was collected from unvaccinated and vaccinated study participants, and the amount of saliva secreted per minute was noted. Salivary pH and buffering capacity (by 5 mmol Hydrochloric acid titration) were measured using a benchtop digital pH meter. The data obtained were compared between unvaccinated and vaccinated participants using an independent t-test.Results: The results showed a significantly higher salivary secretion rate in unvaccinated than vaccinated study participants (0.83 ± 0.24 mL/min vs 0.67 ± 0.24 mL/min, p = 0.001). Similarly, unvaccinated subjects compared to vaccinated subjects exhibited a significantly higher pH (7.33 ± 0.39 vs 7.04 ± 0.46, p < 0.001) and buffering capacity (6.31 ± 1.55 vs 5.40 ± 1.22, p < 0.001). Moreover, unvaccinated females demonstrated a significantly higher salivary secretion (0.87 ± 0.23 vs 0.71 ± 0.25, t = 2.627, p = 0.011) and buffering capacity 6.19 ± 1.52 vs 5.34 ± 1.25, t = 2.404, p = 0.019) than vaccinated females. Similarly, unvaccinated male exhibited significantly higher salivary secretion (0.80 ± 0.25 vs 0.64 ± 0.23, t = 2.670, p = 0.009), salivary pH (7.39 ± 0.45 vs 6.94 ± 0.41, t=4.309, p< 0.001) and buffering capacity (6.42 ± 1.60 vs 5.45 ± 1.21, t = 2.875, p = 0.005) than the vaccinated male subjects.Conclusion: The vaccinated subjects showed a significantly lower mean salivary secretion, pH, and buffering capacity than unvaccinated participants. Hence, COVID-19 vaccination is likely to affect salivary parameters among pediatric patients.Keywords: COVID-19, vaccine, salivary secretion, pH, buffer, pediatric, patients

The effect of tensile and compressive stress on floating-gate and nitride trap based on nonvolatile memory (NVM) retention time is investigated. The results have shown that the retention time under tensile stress has resulted from stress-altered changes in the Si[O.sub.2]/Si barrier height and out-of-place conductivity mass for floating-gate memories and from changes in the trap activation energy in nitride based memories.

Muhanad Abdul Kareem AlHaj, Mohammad Abdul Baseer, Abdulrahman Dahham AlSaffan, Navin Anand Ingle Preventive Dentistry Department, College of Dentistry, Riyadh Elm University, Riyadh, Saudi ArabiaCorrespondence: Mohammad Abdul Baseer, Preventive Dentistry Department, College of Dentistry, Riyadh Elm University, Namuthajiya Campus, PO Box No 84891, Riyadh, 11681, Saudi Arabia, Email ma_baseer@riyadh.edu.saBackground: The COVID-19 lockdown affected oral health behaviors. This study aims to assess and compare the oral health attitudes and behaviors of first-time and previous patients undergoing dental extractions during the COVID-19 pandemic at private dental clinics in Riyadh City, Saudi Arabia.Methods: This cross-sectional study was conducted among patients aged 18– 65 years undergoing dental extractions at private dental clinics in Riyadh City, Saudi Arabia. Four hundred and eighty patients were selected using a convenient sampling methodology. A structured, close-ended questionnaire investigated demographic information, tooth extraction attendance, and oral health attitudes and behaviors using 20 items Hiroshima University Dental Behavioral Inventory (HUDBI).Results: A total of 480 exodontia patients [282 (58.8%) males and 198 (41.2%) females] participated in this study. All patients used a stiff-bristled toothbrush and were concerned about their teeth’ color and bad breath. Similarly, all the participants did not feel brushed unless they used strong strokes, and the dentist told them to brush very well. An overall mean HUDBI score of 6.34± 1.12 was observed. Patients with a primary education (5.61± 0.79), income ≤ 5000 SAR (6.00± 0.92), residing in rural areas (5.84± 0.93), and government employees (5.62± 0.96) exhibited lower HU-DBI scores compared to their counterparts. The study revealed a significant variation in HUDBI scores across different demographic factors, including education, income, residence, occupation, and reason for extraction (p< 0.001). The HUDBI score of first-time attendees to dental extraction (5.88± 1.03) was found to be significantly poorer than to those of previous attendees (6.63± 1.09), (p< 0.001).Conclusion: Patients who underwent dental extractions at private dental clinics in Riyadh City, Saudi Arabia, during the post-lockdown COVID-19 pandemic exhibited average oral health attitudes and behaviors. Oral health attitudes and behaviors differed by socioeconomic status. Patients undergoing dental extractions for reasons other than dental caries and periodontal diseases and first-time attendees demonstrated poor oral health attitudes and behaviors.Keywords: attitude, behavior, tooth extraction, oral health, private dental clinics, pandemic

We have investigated the growth mechanism and surface structure of magnetite (Fe3O4) films grown on semiconducting ZnO substrates. Growth proceeds in a wetting layer plus island-mode and a later coalescence of islands, as was verified by electron diffraction, topography measurements of the surface, and the investigation of the microstructure. The typical (111) surface diffraction pattern magnetite is observed already at the early island growth stage. Due to the island-like growth mode, domain boundaries form upon coalescence of the islands. Twin boundaries have been evidenced between neighboring domains. Island growth enables partial relaxation of the misfit strain. [ABSTRACT FROM AUTHOR]

We present resonant soft x-ray scattering studies of Ti 3d and O 2p states at the interfaces of SrTiO3/LaAlO3 superlattices. From reflectivity analyses, focusing on the (003) peak which is forbidden for our “ideal” superlattice structure, we concluded that the LaO|TiO2/SrO and the SrO|AlO2/LaO interfaces have distinct reconstructions, breaking the heterostructure symmetry. [ABSTRACT FROM AUTHOR]

Within the study of oxide materials, high pressure bulk growth has generated a number of new and interesting materials. More recently, attention has been paid to using epitaxy to stabilize these high pressure oxide materials as thin films. In this article we report on the molecular beam epitaxial growth of SrCu[sub 2]O[sub 3]; a high pressure, highly correlated, model oxide. We find that the choice of substrate can significantly alter not only the structure but also the chemistry of the resulting film. For growth on SrTiO[sub 3] substrates the epitaxially stabilized structure for single phase films with a SrCu[sub 2]O[sub 3] composition is based on a tetragonal unit cell. For identical growth conditions, but on a LaA1O[sub 3] substrate, a single phase film with the composition and structure of the infinite layer material (SrCuO[sub 2]) is formed. We also review the literature for the successes and failures of epitaxy to stabilize high pressure structures. [ABSTRACT FROM AUTHOR]

Presents information on a study which carried out transport critical current measurements on melt-processed thick films on yttria-stabilized zirconia. Background of the study; Methodology of the study; Results and discussion.

Rayyan Abdallah Alwazzan, Mohammad A Baseer, Osamah Mohammed ALMugeiren, Navin Anand Ingle Department of Preventive Dentistry, College of Dentistry, Riyadh Elm University, Riyadh, Saudi ArabiaCorrespondence: Mohammad A BaseerDepartment of Preventive Dentistry, College of Dentistry, Riyadh Elm University, Namuthajiya Campus, PO Box No. 84891, Riyadh, 11681, Saudi ArabiaEmail ma_baseer@riyadh.edu.saBackground: Given the COVID-19 pandemic, it is necessary to assess the dentist’s knowledge, preventive awareness, and attitude towards COVID-19 in Saudi Arabia. This study aimed to assess dental professionals’ knowledge, preventive awareness, and attitude towards dental care during the COVID-19 pandemic in Saudi Arabia.Study Subjects and Methods: The study participants consisted of dental professionals working in government, private and academic sectors in Saudi Arabia. An online questionnaire (Whatsapp and Twitter) was sent to dental professionals in July 2020. The questionnaire consisted of questions on dental professional’s demographic variables, their knowledge of the incubation period, the symptoms, mode of transmission, preventive awareness of COVID-19, and their attitude toward treating patients with COVID-19. Mann–Whitney U and Kruskal–Wallis tests were applied to compare mean ranks and a p< 0.05 is considered statistically significant.Results: This study included a total of 356 dental professionals (dentists and dental students) aged 22– 60 years (mean±SD, 32.14± 7.48 years). Majority of the participants were graduates/general practitioners (GP) 145 (40.7%), followed by post graduate (PG) student 108 (30.3%), undergraduate students 23 (6.5%) and specialist 80 (22.5%). Dental professionals showed a high level (> 90% correct responses) of knowledge of COVID-19 except for the infection among comorbid patients 283 (79.5%) and incubation period of COVID-19, 164 (46.1%). An overall high knowledge of COVID-19 (87.26%), preventive awareness (88.64%) and a positive attitude (65.26%) towards dental care were observed among the study participants. The mean knowledge ranks differed significantly in different genders (p=0.029) and marital status (p=0.023), whereas preventive awareness differed significantly across various qualifications (p=0.004). The mean attitude rank was significantly higher among Saudi (182.29) compared to non-Saudi (141.36) study participants (p=0.025).Conclusion: The dental professionals participated in this study demonstrated adequate knowledge of symptoms, preventive awareness, and a positive attitude towards dental care of the COVID-19 infected patients.Keywords: attitude, awareness, COVID-19, dental professional, knowledge

India with the second largest population of world is under the threat of severe water scarcity, the major portion of India's fresh water requirement is completed by rivers, rivers play very important role in providing drinking water, irrigation water, electricity, transportation and other miscellaneous works has been done with the help of rivers, in order to fulfill increasing demand for water, India needs to make clever use of all sources of water. Mapping water area of river system helps to identify the availability of water in the specific region of a river, an attempt is made to map or highlight the water area in aerial images of river, the image processing tools like morphology and segmentation is used to detect and map water areas. To enhance the computing performance GPU-accelerated computing techniques and two different NVIDIA's graphics processing units are used. The complete work is done on actual images of Godavari River at Nasik region of Maharashtra. [ABSTRACT FROM AUTHOR]