Examinations the Optical, Mechanical, and Shielding Properties of Ag2O doped B2O3–Bi2O3–SrF2–Na2O Glasses for Gamma Ray Shield Applications

A series of five glass samples have a chemical composition of (55-x) B2O3 + 5 Bi2O3 + 20SrF2 + 20Na2O + xAg2O with varied doping ratios x = 0, 1, 2, 3, and 4 mol% were fabricated using the melt quenching technique to study the effect of B2O3 replacement by Ag2O on the physical, mechanical, optical and gamma-ray shielding capacity of the fabricated glasses. The Cary 5000 UV–Vis–NIR measured the optical absorption in the wavelength range between 200 and 3000 nm. Based on the measured optical absorption, energy (direct/indirect) bandgap and Urbach energy were calculated. Moreover, the measured samples density, molar volume, packing density, dissociation energy, and mechanical properties for the fabricated glasses were calculated using the concepts of the Makishima-Mackenzie model. In this regard, the microhardness was decreased from 4.070 to 3.931 GPa with raising the Ag2O concentration. The effect of B2O3 replacement on the shielding capacity was also evaluated using the Monte Carlo simulation. The simulation results showed that the replacement of B2O3 causes a significant increase in the shielding parameters like linear attenuation coefficient and radiation shielding capacity. The best radiation shielding properties were achieved for a glass sample with 4 mol% Ag2O compound. Its linear attenuation coefficient varied between 8.091 and 0.134 cm−1, raising the gamma photon energy between 0.059 and 2.506 MeV. © 2022, The Author(s)

IoT-Enabled Big Data Analytics Architecture for Multimedia Data Communications

The present spreading out of the Internet of Things (IoT) originated the realization of millions of IoT devices connected to the Internet. With the increase of allied devices, the gigantic multimedia big data (MMBD) vision is also gaining eminence and has been broadly acknowledged. MMBD management offers computation, exploration, storage, and control to resolve the QoS issues for multimedia data communications. However, it becomes challenging for multimedia systems to tackle the diverse multimedia-enabled IoT settings including healthcare, traffic videos, automation, society parking images, and surveillance that produce a massive amount of big multimedia data to be processed and analyzed efficiently. There are several challenges in the existing structural design of the IoT-enabled data management systems to handle MMBD including high-volume storage and processing of data, data heterogeneity due to various multimedia sources, and intelligent decision-making. In this article, an architecture is proposed to process and store MMBD efficiently in an IoT-enabled environment. The proposed architecture is a layered architecture integrated with a parallel and distributed module to accomplish big data analytics for multimedia data. A preprocessing module is also integrated with the proposed architecture to prepare the MMBD and speed up the processing mechanism. The proposed system is realized and experimentally tested using real-time multimedia big data sets from athentic sources that discloses the effectiveness of the proposed architecture

Humoral Immunogenicity and Efficacy of a Single Dose of ChAdOx1 MERS Vaccine Candidate in Dromedary Camels

MERS-CoV seronegative and seropositive camels received a single intramuscular dose of ChAdOx1 MERS, a replication-deficient adenoviral vectored vaccine expressing MERS-CoV spike protein, with further groups receiving control vaccinations. Infectious camels with active naturally acquired MERS-CoV infection, were co-housed with the vaccinated camels at a ratio of 1:2 (infected:vaccinated); nasal discharge and virus titres were monitored for 14 days. Overall, the vaccination reduced virus shedding and nasal discharge (p = 0.0059 and p = 0.0274, respectively). Antibody responses in seropositive camels were enhancedby the vaccine; these camels had a higher average age than seronegative. Older seronegative camels responded more strongly to vaccination than younger animals; and neutralising antibodies were detected in nasal swabs. Further work is required to optimise vaccine regimens for younger seronegative camels

Seroprevalence of SARS-CoV-2 (COVID-19) among Healthcare Workers in Saudi Arabia: Comparing Case and Control Hospitals

Healthcare workers (HCWs) stand at the frontline for fighting coronavirus disease 2019 (COVID-19) pandemic. This puts them at higher risk of acquiring the infection than other individuals in the community. Defining immunity status among health care workers is therefore of interest since it helps to mitigate the exposure risk. This study was conducted between May 20th and 30th, 2020. Eighty-five hospitals across Kingdom of Saudi Arabia were divided into 2 groups: COVID-19 referral hospitals are those to which RT-PCR-confirmed COVID-19 patients were admitted or referred for management (Case-hospitals). COVID-19 nonaffected hospitals where no COVID-19 patients had been admitted or managed and no HCW outbreak (Control hospitals). Next, seroprevalence of severe acute respiratory syndrome coronavirus 2 among HCWs was evaluated; there were 12,621 HCWs from the 85 hospitals. There were 61 case-hospitals with 9379 (74.3%) observations, and 24 control-hospitals with 3242 (25.7%) observations. The overall positivity rate by the immunoassay was 299 (2.36%) with a significant difference between the case-hospital (2.9%) and the control-group (0.8%) (P value <0.001). There was a wide variation in the positivity rate between regions and/or cities in Saudi Arabia, ranging from 0% to 6.31%. Of the serology positive samples, 100 samples were further tested using the SAS2pp neutralization assay; 92 (92%) samples showed neutralization activity. The seropositivity rate in Kingdom of Saudi Arabia is low and varies across different regions with higher positivity in case-hospitals than control-hospitals. The lack of neutralizing antibodies (NAb) in 8% of the tested samples could mean that assay is a more sensitive assay or that neutralization assay has a lower detection limits; or possibly that some samples had cross-reaction to spike protein of other coronaviruses in the assay, but these were not specific to neutralize severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)

Radiation dose to Malaysian populace via the consumption of roasted ground and instant coffee

Accompanying the busy lifestyles of modern Malaysia, coffee is becoming one of the nations’ most popular stimulating drinks. In association with nutrients uptake, natural radionuclides in soil are also being taken up by the coffee plant, subsequently appearing in the human body through consumption of coffee. Present study concerns the assessment of the natural radionuclides 226Ra, 228Ra, and 40K in roasted ground and instant coffee consumed in Malaysia. A total of 12 sampled brands of coffee, originating from seven different countries including Malaysia, were collected from various supermarkets in Kuala Lumpur. The samples were analyzed by HPGe γ-ray spectrometry, obtaining a range of activities (in Bq/kg) 6.4 ± 1.3–21.4 ± 2.4, 6.6 ± 1.8–47.9 ± 10.6, and 220 ± 12–1510 ± 72 for 226Ra, 228Ra and 40K respectively. The annual committed effective dose estimate from such coffee consumption was found to be in the range 13.2–55.7 μSv/y, low in comparison with the UNSCEAR (2000) reference dose guidance limit of 290 μSv/y. The estimated threshold coffee consumption rates indicates a guidance limitation for Sample L of not more than 21 g/d (some 2 cups/d) to avoid deleterious health effect. While the presently sampled coffee brands do not represent a public concern in terms of radiological risk, cumulative daily dietary exposures from other or present brands may not be totally negligible because of the UNSCEAR reference limit is due to the contribution from all natural sources. Thus, periodic monitoring of radiation levels in coffee is suggested to be of importance

Factors associated with diabetic foot among type 2 diabetes in Northern area of Saudi Arabia: a descriptive study

Abstract Objective Foot complications are considered to be a devastating consequence of type 2 diabetes mellitus (T2DM), posing a major medical and economic burden. A prospective study was conducted at researchers’ area “Northern area of Saudi Arabia” to determine the factors associated with diabetic foot (DF) among T2DM patients. Identifying the extent of this problem and the associated factors will enable the health providers to imply early preventive measurements. Results Two hundred T2DM patients with/without DF (n = 100 for each group) were recruited. In total, the mean (SD) age of participants was 56 (± 12.2) years and nearly 70% of the patients were females. They showed a trend for higher frequency of impaired vibration perception, light touch pressure, proprioception and pain sensation than males in T2DM with DF. In univariate analysis, older age, long duration of diabetes and poor glycemic control reflected in high levels of HbA1c were significant factors associated with DF (OR = 4.1, 95% CI 2.3–7.4, P < 0.0001; OR = 6.5, 95% CI (4.9–9.3), P < 0.0001, and OR = 1.1, 95% CI (1.05–1.3), P = 0.002, respectively). Taken together, the current results could highlight the importance of epidemiological studies to raise the awareness of this important health care problem around the country

Validity and reliability of the Arabic sedentary behavior questionnaire among university students aged between 18–30 years old

Abstract Purpose The study aimed to test the validity and reliability of the Arabic version of the sedentary behavior questionnaire (SBQ). Methods A total of 624 university students (273 males; 351 females, mean age = 20.8 years) were recruited from Taibah University, Madinah, Saudi Arabia. For criterion and constructive validity (n = 352), the Arabic SBQ was compared with total sitting time from the International Physical Activity Questionnaire-short form (IPAQ-SF) and the International Physical Activity Questionnaire-long form (IPAQ-LF). For concurrent validity, the English and Arabic SBQ versions were given concurrently to bilingual university students (n = 122) once. For test–retest reliability, the Arabic SBQ was given twice to participants (n = 150) at a one-week interval. Results Sitting time of IPAQ-SF (7th question: sitting time on weekdays) and IPAQ-LF (21st question: sitting time on weekdays and 22nd question: sitting time on weekends) correlated significantly with total sitting time/week of the Arabic SBQ (r = 0.29, p = 0.003; r = 0.14, p = 0.02, respectively). Motorized transportation measured with the IPAQ-LF correlated significantly with time spent driving in a car, bus, or train from the Arabic SBQ on weekdays and weekends (r = 0.53, p < 0.001; r = 0.44 p < 0.001, respectively). The total sitting time of the Arabic SBQ was inversely correlated with BMI (r = -0.18, p = 0.001). The correlations between the Arabic and the English SBQ versions ranged from 0.25–0.96; p < 0.001 on weekdays and 0.50–0.90; p < 0.001 on weekends. Moderate to good reliability was also found between test and retest for all SBQ items and total score during weekdays (0.72 to 0.8), and weekends (0.64 to 0.87), with exception of the 7th item "play musical instrument", ICC = 0.46). Mean difference of test–retest of the Arabic SBQ was not significantly different from zero for the total sitting time of the Arabic SBQ (t = -0.715, P = 0.476). Conclusion The Arabic SBQ had satisfactory levels of reliability, with total sitting time of the Arabic SBQ correlating significantly with sitting times derived from IPAQ-SF, IPAQ-LF, and the English SBQ versions. Hence, the Arabic SBQ can be used as a tool to measure sedentary behavior among adult Arabs aged between 18 to 30 years old in future epidemiologic and clinical practice

Immunogenicity of High-Dose MVA-Based MERS Vaccine Candidate in Mice and Camels

The Middle East respiratory syndrome coronavirus (MERS-CoV) is a zoonotic pathogen that can transmit from dromedary camels to humans, causing severe pneumonia, with a 35% mortality rate. Vaccine candidates have been developed and tested in mice, camels, and humans. Previously, we developed a vaccine based on the modified vaccinia virus Ankara (MVA) viral vector, encoding a full-length spike protein of MERS-CoV, MVA-MERS. Here, we report the immunogenicity of high-dose MVA-MERS in prime–boost vaccinations in mice and camels. Methods: Three groups of mice were immunised with MVA wild-type (MVA-wt) and MVA-MERS (MVA-wt/MVA-MERS), MVA-MERS/MVA-wt, or MVA-MERS/MVA-MERS. Camels were immunised with two doses of PBS, MVA-wt, or MVA-MERS. Antibody (Ab) responses were evaluated using ELISA and MERS pseudovirus neutralisation assays. Results: Two high doses of MVA-MERS induced strong Ab responses in both mice and camels, including neutralising antibodies. Anti-MVA Ab responses did not affect the immune responses to the vaccine antigen (MERS-CoV spike). Conclusions: MVA-MERS vaccine, administered in a homologous prime–boost regimen, induced high levels of neutralising anti-MERS-CoV antibodies in mice and camels. This could be considered for further development and evaluation as a dromedary vaccine to reduce MERS-CoV transmission to humans