King Abdulaziz City For Science And Technology Research Articles

Examining UV Radiation Patterns in Relation to Particulate Matter and Atmospheric Conditions in Arid, Unclouded Skies

This study investigates the influences of air temperature (T), relative humidity (RH), wind speed (WS), clearance index (KT), particulate matter (PM) concentrations (PM10 and PM2.5), and aerosol optical depth (AOD) on ultraviolet (UV) radiation during clear skies in Riyadh, central Saudi Arabia. The observational dataset utilized in this study comprises global solar radiation (G), UVA radiation, AOD measurements, and PM concentrations. The data were collected from 2014 to 2015 at the King Abdulaziz City for Science and Technology (KACST) campus in Riyadh. Regression analyses were conducted to investigate the relationships between UV radiation and the considered variables. The methodology is based on the least square method and associated statistical tests. The findings of this study provide valuable insights into the impacts of meteorological variables and aerosols on UV radiation, contributing to the understanding of environmental and industrial applications in the Arabian Peninsula. The analyses showed that the strengths and magnitudes differed from one variable to another. No significant correlations between UVA radiation (315–400 nm) and hourly and daily values of PM2.5 were found. Moreover, no significant correlations were seen between daily values of the UVA radiation and RH and between the UVB (280–315 nm) and PM10. The rest of the correlations (between UV radiation and the PM10 and meteorological variables) were found to be significant. While WS, the ratio of the PM concentrations (PM2.5/PM10), KT, and T exhibited positive correlations with UV radiation, the rest of the variables had anti-correlations with UV radiation. The influences of T, WS, and RH on ambient PM concentrations during the considered period were taken into account, and it was found that the PM concentrations correlate, with different magnitudes and strengths, positively with T and negatively with RH and WS.

Arabicization via Loan Translation: A Corpus-based Analysis of Neologisms Translated from English into Arabic in the Field of Information Technology

Abstract This study aims to use a corpus-based analysis to examine loan translation (LT) as an Arabicization technique in Written Standard Arabic (WSA) for information technology (IT) and investigate the factors impacting LT formation. Data were collected from four corpora: four Arabic online newspapers, the Microsoft Language Portal, two user manuals, and the Arabic Corpus of King Abdul-Aziz City for Science and Technology (KACST). Four LT strategies were identified: morphosyntactic pattern alteration, literal translation, loan blending, and metaphorical extension. Literal translation occurred in three degrees: full LTs, partial LTs, and non-LTs, through calquing. Metaphors based on functional similarity played a crucial role in understanding and accepting IT terms in WSA. Paradigmatic variation prevailed in LTs, with synonymous variations more common than nonsynonymous ones, and no syntagmatic variation. The KACST analysis showed significant differences in occurrence frequency among LT variants. LT formation and variation were influenced by linguistic factors such as lexical need, semantic transparency, and lexical borrowing, as well as extralinguistic factors such as nationalism and lack of coordination among Arabic language academies. The study concludes with implications for addressing the absence of coordination between these academies and improving IT-related LT quality between English and WSA.

The mammalian sperm factor phospholipase C zeta is critical for early embryo division and pregnancy in humans and mice.

The mammalian sperm factor phospholipase C zeta is critical for early embryo division and pregnancy in humans and mice.

Exploring the relationship between space weather parameters and cosmic ray muons observed at high cut-off rigidity site: A correlation, artificial neural network, and spectral analysis

The objective of this study was to examine the relationship between cosmic rays (CR) and various solar activity parameters, including the interplanetary magnetic field (B), solar radio emission flux at 10.7 cm (F10.7), solar wind speed (V), solar wind density (N), solar wind pressure (P), and the variance of the interplanetary magnetic field vector (σF). The CR data collected from 2007 to 2013 were obtained using a muon detector situated at King Abdulaziz University (KAAU) in Jeddah, Saudi Arabia, with a rigidity cutoff of 14.8 GV. To explore the correlation between the CR data and the selected parameters, three distinct methods were employed: regression analysis, artificial neural network (ANN), and power spectral analysis.Regression analysis revealed significant positive correlations between CR muons and plasma pressure (R = 0.1, p < 0.05), as well as solar wind speed (R = 0.1, p < 0.05). On the other hand, negative correlations were observed between CRs and radio flux (R = 0.75, p < 0.05), as well as interplanetary magnetic field (R = 0.1, p < 0.05). However, no significant correlations were found between CRs and plasma density or the variance of the interplanetary magnetic field vector (p > 0.05). Furthermore, multivariable correlation analyses were conducted to explore the relationship between CR muons and the considered parameters, resulting in only marginal improvement.For comparison purposes, data from the King Abdulaziz City for Science and Technology (KACST) muon detector in Riyadh, Saudi Arabia (with a rigidity cutoff of 14.4 GV), as well as CR data from Oulu NM (with a rigidity cutoff of 0.3 GV), were utilized for the same period as the KAAU data. The correlation results indicated that the relationships between the CR data from the three detectors and some of the considered parameters were consistent. However, the strength of the correlations and the magnitudes of the slopes exhibited variations.ANN procedures were also employed to compare the efficiency of neural network analysis in forecasting CR muons based on solar activity parameters. The Multilayer Perceptron (MLP) Module trained using the backpropagation learning algorithm was utilized to build a neural network model and assess its accuracy. The results indicated that the ANN method provided slightly more accurate predictions compared to regression analysis.Finally, Fast Fourier Transform (FFT) analyses were conducted to examine the presence of periodicities between the CRs and the variables under consideration. The analysis revealed several shared periodicities, including cycles spanning 270–277 days, 146–158 days, 89–95 days, 66–73 days, and 21–31 days.

Commissioning Results of the New Compact ECR Ion Source for Electrostatic Storage Ring at KACST

A compact microwave ECR ion source with low operating power was tested and commissioned for the ion injector line in the multipurpose low-energy ELASR storage ring facility at King Abdulaziz City for Science and Technology (KACST) in Riyadh. The compact ECR ion source can deliver singly charged ions with an energy of up to 50 keV and a beam current of up to 50 μA or up to 500 µA with a larger extraction aperture. The plasma in the ECR chamber is driven by a simple transmitter antenna, making the overall size of the ion source only 6 cm in diameter, which is relatively small when compared with other ECR systems. Additionally, the source operates without a high-voltage platform, which significantly reduces the overall footprint and simplifies the system operation. In this paper, the mechanical design and modeling of the ECR ion source are introduced, and the layout of the first part of the beam line is presented along with the numerical simulation results. In addition, the experimental results obtained for the first generated ion beam and commissioning of the ECR ion source are introduced and discussed.

Cosmic ray measurements at high cutoff rigidity site - Preliminary results

In January 2007, King Abdulaziz University, Jeddah (21.5o N; 39.2o E; 14.8 GV), Saudi Arabia, installed a single channel muon detector for monitoring and studying the variations of the cosmic ray (CR) muons. Brief description of the developed detector will be presented. A few results obtained by the detector so far will be given and discussed. These include the impact of the atmospheric pressure and temperature, the daily variations, the responses of the detector to transit and long term of the solar disturbances. Performances of the detector were compared with the King Abdulaziz city for science and technology (KACST) muon detector installed in Riyadh Saudi Arabia and with the Oulu neutron monitor at Oulu and showed comparable results.

Multigeneration source based on novel triple-component chiller configuration co-supplied with renewable and fossil energy operated in Arabic Peninsula conditions

Innovative hybrid source for electricity, cooling and desalinated water production based on a mixed fossil fuel/solar energy supply, equipped with triple-component chiller configuration, has been presented in the paper. The system was erected and recently commissioned in King Abdulaziz City for Science and Technology (KACST) in Kingdom of Saudi Arabia to operate as a working laboratory supplying media to adjacent buildings of the Solar Village complex. In the Arabian Gulf region, increased demand, especially for cooling and desalinated water, as well as fluctuating availability of electricity from the grid in summer period is visible, what makes such a stand-alone installation operation justified especially in remote areas. Abundant availability of intermittent solar energy correlated with cooling demand led to development of novel triple-component chiller configuration consisting of absorption, adsorption and compressor chiller. Two Diesel internal combustion engines had been selected to supply electricity and heating when solar energy is not available. Paper presents results of installation commissioning, during which the performance of the system for three different operating scenarios was assessed. Maximum efficiency was achieved for maximum renewable energy production option reaching 324.91% with renewable share at a level of 89.99%. For the maximum cooling capacity production, the efficiency of the system was 124.89% with 18.6% share of renewable energy. The lowest efficiency, of 93.09%, system obtained for the night scenario.

PREFACE

ICSDI 2022 is the most dynamic, informative, inspirational, and innovative event organized by the Engineering College of Prince Sultan University (Riyadh, KSA). The 2022 conference focuses on the State of the Art and Practice in different sustainable development goals (SDGs), as one of the promising and trending Engineering disciplines, this field is still changing rapidly. Along with the diversity of presentations on challenging projects and research, ICSDI 2022 will feature multiple invited speakers on selected topics. The conference will include a wide range of knowledge-enhancing technical and panel sessions, short courses, and workshops.There are around 96 participants attending the conference in the opening ceremony and plenary sessions. They are from the United States, Germany, Canada, India, Brazil, Chile, China, Egypt, Russia, Georgia, Hong Kong and so on. The conference was held in hybrid, both physical and virtual mode due to covid19 restrictions in few countries. Around 18 participants attended in virtual mode. At this conference, we were greatly honored to have outstanding Keynote Speakers and Invited Speakers from different countries. They addressed the audience and shared their knowledge and rich experience in related fields. They are Prof. Dennis D. Truax from Mississippi State University, USA; Mr. Ziyad Alshiha, Group Chief executive of The Saudi Investment Recycling Company (SIRC), Saudi Arabia; Dr. Adam C. BOULOUKOS, The UNDP Resident Representative for the Kingdom of Saudi Arabia; Eng. Turki Bukhari, Vice President, Assets & Facilities Management, Expro, Saudi Arabia; Mr. Raed Albasseet, Chief Environment and Sustainability Officer of the Red Sea Development Company & AMAALA; Eng. Fahad Al Ajlan, President, KAPSARC; Mr. Mark Mirza, Project Leader at Fraunhofer ISC, Germany; Ms. Mayssam Tamim, Assistant Resident Representative; Dr Ahmed Al-Darwish, Deputy Governor for Development, Economic Research & Policy Advocacy; Dr. Ahmad Alwosheel, Assistant Researcher at King Abdulaziz City for Science and Technology (KACST); Eng. Mazin Albahkali, Executive Vice President Strategic Planning and New Business Development, Saudi Electricity Company (SEC), Saudi Arabia; Mr. Bandar Al Blehed Clients Relations Development Head -Saudi Exchange; Dr. Abdullah Alabdulkarem Executive Director of the Enablement Sector at the Government Expenditure and Projects Efficiency Authority (EXPRO); Eng. Waleed AlGhamdi, Associate Director, Smart City & Sustainability; Mr. Turki A. Alrowili, Spokesperson, Public Relations and Communication Director at National Development Fund; Dr. Ameer M. Al-Alwan, Advisory and Training Director, Center for Local Governance.There are 16 sub-sessions during the conference. The tracks of the conference include Manufacturing and Industrial Systems towards Sustainability, Sustainable Construction Technologies and Materials, Energy Sustainability: Challenges and Opportunities, Sustainable Urbanization and Smart Cities, Sustainability and Built Environment, Policies, Regulations and Economic Assessments towards SDGs. Attendees, paper presenters, keynote speakers, scholars and students have benefited in many ways from this conference. We would like to express our great appreciation to the organizers, members of the program committees and reviewers of ICSDI 2022 for their hard work. Without their participation, it would be impossible to hold ICSDI 2022 successfully and ensure the high quality of papers of the conference proceedings. We also would like to express our gratitude to the unbelievable number of authors for contributing their research results to the conference.List of Committees, Statement of Peer Review are available in this pdf.

Oocyte activation deficiency and assisted oocyte activation: mechanisms, obstacles and prospects for clinical application.

BACKGROUNDOocyte activation deficiency (OAD) is attributed to the majority of cases underlying failure of ICSI cycles, the standard treatment for male factor infertility. Oocyte activation encompasses a series of concerted events, triggered by sperm-specific phospholipase C zeta (PLCζ), which elicits increases in free cytoplasmic calcium (Ca2+) in spatially and temporally specific oscillations. Defects in this specific pattern of Ca2+ release are directly attributable to most cases of OAD. Ca2+ release can be clinically mediated via assisted oocyte activation (AOA), a combination of mechanical, electrical and/or chemical stimuli which artificially promote an increase in the levels of intra-cytoplasmic Ca2+. However, concerns regarding safety and efficacy underlie potential risks that must be addressed before such methods can be safely widely used.OBJECTIVE AND RATIONALERecent advances in current AOA techniques warrant a review of the safety and efficacy of these practices, to determine the extent to which AOA may be implemented in the clinic. Importantly, the primary challenges to obtaining data on the safety and efficacy of AOA must be determined. Such questions require urgent attention before widespread clinical utilization of such protocols can be advocated.SEARCH METHODSA literature review was performed using databases including PubMed, Web of Science, Medline, etc. using AOA, OAD, calcium ionophores, ICSI, PLCζ, oocyte activation, failed fertilization and fertilization failure as keywords. Relevant articles published until June 2019 were analysed and included in the review, with an emphasis on studies assessing large-scale efficacy and safety.OUTCOMESContradictory studies on the safety and efficacy of AOA do not yet allow for the establishment of AOA as standard practice in the clinic. Heterogeneity in study methodology, inconsistent sample inclusion criteria, non-standardized outcome assessments, restricted sample size and animal model limitations render AOA strictly experimental. The main scientific concern impeding AOA utilization in the clinic is the non-physiological method of Ca2+ release mediated by most AOA agents, coupled with a lack of holistic understanding regarding the physiological mechanism(s) underlying Ca2+ release at oocyte activation.LIMITATIONS, REASONS FOR CAUTIONThe number of studies with clinical relevance using AOA remains significantly low. A much wider range of studies examining outcomes using multiple AOA agents are required.WIDER IMPLICATIONSIn addition to addressing the five main challenges of studies assessing AOA safety and efficacy, more standardized, large-scale, multi-centre studies of AOA, as well as long-term follow-up studies of children born from AOA, would provide evidence for establishing AOA as a treatment for infertility. The delivery of an activating agent that can more accurately recapitulate physiological fertilization, such as recombinant PLCζ, is a promising prospect for the future of AOA. Further to PLCζ, many other avenues of physiological oocyte activation also require urgent investigation to assess other potential physiological avenues of AOA.STUDY FUNDING/COMPETING INTERESTSD.G. was supported by Stanford University’s Bing Overseas Study Program. J.K. was supported by a Healthcare Research Fellowship Award (HF-14-16) made by Health and Care Research Wales (HCRW), alongside a National Science, Technology, and Innovation plan (NSTIP) project grant (15-MED4186-20) awarded by the King Abdulaziz City for Science and Technology (KACST). The authors have no competing interests to declare.

Correlation Analyses between Ultraviolet Radiation, Global Solar Radiation, and Metrological Variables and the COVID-19 Cases in Arid Climate

The transmission of infectious diseases is influenced by several meteorological factors. In this study, the influence of several such factors in the transmission of COVID-19 (from 26 March 2020 to 29 July 2021) in the arid weather of Riyadh, Saudi Arabia was investigated using the Spearman and Kendall rank tests. The factors considered were the average, maximum, and minimum values of air temperatures, air pressure, wind speed, relative humidity, absolute humidity, dew point temperatures, and the average values of the global solar radiation and ultraviolet radiation at bands A and B. The data on meteorological factors were obtained from the King Abdulaziz City for Science and Technology (KACST) weather station, whereas the data on the daily COVID-19 cases were obtained from the official webpage of the Saudi Arabian Ministry of Health (MOH). The results revealed that air temperature (average, minimum, and maximum) average and maximum wind speed, maximum dew point temperature, global solar radiation, and ultraviolet radiation at A and B bands are positively associated with the daily number of COVID-19 cases reported in Riyadh. However, relative humidity, atmospheric pressure (averages, minimum, and maximum) is anti-correlated with the number of daily COVID-19 cases, while absolute humidity exerts no influence. These results are in total agreement with some of the previously established studies and are either contradicted partly or totally with others conducted at several locations around the world. The results could help not only epidemiologists understand the behavior of COVID-19 against meteorological variables but also national and international organizations and healthcare policymakers devise control strategies to combat the virus.

Cosmic rays detection in Saudi Arabia: Review of the facilities and preliminarily results

Solar activity modulates cosmic ray (CR) particles with different magnitudes on different time scales. CR modulations have been studied using ground-based detectors, primarily neutron monitors, distributed around the world. In 2002, CR research began in Saudi Arabia with the installation of the first CR detector at the King Abdulaziz City for Science and Technology (KACST) in Riyadh (lat. 24 43; long. 46 40; Rc ~ 14.4 Gv), the capital of Saudi Arabia. The facility is located in the central Arabian Peninsula. Because of its high cutoff rigidity, the site is ideal for monitoring CR variations and is of great significance to the research community.Different CR detectors employing various measuring techniques have been developed and installed, at this site, to record the intensity of cosmic rays on different time scales and assess their correlation with atmospheric and climatic parameters. They include scintillator detectors, single-channel and rotatable telescopes, multi-wire detectors, CARPET detectors, small mobile detector, and mini-neutron monitors. In this paper, we briefly describe these detectors and offer observations on their use in CR research.

Correlation analyses between solar activity parameters and cosmic ray muons between 2002 and 2012 at high cutoff rigidity

• The impacts of seven solar, interplanetary, and geophysical parameters on CR data have been investigated. • CR data for the period 2002–2012 from KACST muon detector located at high cutoff rigidity have been used. • CR data from Oulu neutron monitor for the same period have been used for comparisons. • Multivariable models were developed to predict CR variability at KACST and Ouu. Solar activity modulates cosmic ray (CR) flux with different magnitudes on different time scales. Several investigations from locations with different, mainly low, cutoff rigidity utilizing different solar activity parameters have been carried out to characterize their influence on the observed CR flux. In this study, the effect of seven solar, interplanetary, and geophysical parameters on the secondary CR muons has been investigated and established using correlation analyses. Daily mean values of the CR data for the period between 2002 and 2012 were obtained from the King Abdulaziz City for Science and Technology (KACST) muon detector, Riyadh, central Saudi Arabia (Rc = 14.4 GV). Considered parameters are sunspot number, radial component of the interplanetary magnetic field, Kp index, solar radio emission flux at 10.7 cm, Dst index, solar wind speed, and solar wind density. Same analyses have been carried out using data from the Oulu neutron monitor (Rc = 0.8 GV) for comparison purposes. Obtained results showed that the intensities of the secondary CRs from both stations are significantly correlated with the Dst index and plasma density, and anti-correlated with the rest of the variables. These results are in agreement with those obtained by several investigators. Magnitude and strength of the correlations between the considered variables and CRs were higher and stronger for the CR neutrons than the CR muons. These findings may be due to the greater influence of seasonal variations on the CR muons than on the CR neutrons. Additionally, the muon detector is sensitive (due to its high cutoff rigidity) to higher-energy CR particles, which are less affected by solar disturbances. Time-lag cross-correlation analyses between the monthly mean CR values from both stations and the monthly mean values of the considered variables were conducted. Comparable results with the previous investigations were found. Multivariable models using the seven parameters were developed to predict the CR variations for both sites. For the data from the KACST detector, the model was able to predict the measured data with a correlation coefficient of 0.48 and a standard deviation of 0.60%. On the other hand, the developed model for the Oulu neutron monitor has a correlations coefficient of 0.77 and a standard deviation of 3.7%.

Charged particle detector-related activities of the KACST radiation detector laboratory

ABSTRACT In 2009, the King Abdulaziz City for Science and Technology (KACST) launched a project involving the establishment of the first radiation detector laboratory in Saudi Arabia. This project aims to design, develop, and operate several multi-purpose radiation detectorsdetectors, as well as to establish collaboration with international institutions to facilitate the transfer of technological knowledge to Saudi scientists. Since the project was launched, several radiation detectors that employ different techniques have been developed by the KACST-based researchers or through their collaboration with international institutes. Data obtained by these detectors are of great importance in several applications, such as in cosmic raycosmic-ray modulation and in solar-terrestrialsolar–terrestrial interaction research. This paper describes the detectors developed thus far and presents some of the obtained results.

The Possible Relationship between the Atmospheric Electric Field and High Energy Charged Particles and the COVID-19 Cases in the Central Arabian Peninsula

Background: Since the beginning of the global COVID-19 pandemic, several studies have been carried out to investigate its spread, with a wide range of factors to understand the influence of the factors that contribute to its spread and to reduce the ongoing threat of COVID-19 pandemic. Methods: In this study, the relationships between the Earth’s electric field and cosmic ray charged particles of different energy ranges and the daily confirmed COVID-19 infections in Riyadh, Saudi Arabia have been investigated using non-parametric statistical tests. The data covered the period between 3 April 2020 and 1st August 2021 and were obtained from the King Abdulaziz City for Science and Technology (KACST) CARPET detector, Riyadh, Saudi Arabia. The electric fields data were obtained from electric field monitor (EFM) deployed on the rooftop of the KACST laboratory. The data of the daily COVID-19 cases were obtained from the official webpage of the Saudi Arabian Ministry of Health (MOH). Results: The results revealed that that the number of COVID-19 cases is correlated with cosmic ray charged particles and anti-correlated with the Earth’s electric field. Conclusion: While the exact mechanism explaining the influence of Earth’s electric field and cosmic rays variations on the reported number of COVID-19 cases is not yet established, the results presented in this study can add additional knowledge to our understanding of the effects of additional factors on influenza activities.

One Health-based control strategies for MERS-CoV

Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is one of the major threats to the healthcare systems in some countries, especially in the Arabian Peninsula MERS-CoV is considered an ideal example of the One Health concept This is due to the animals especially dromedary camels play important roles in the transmission and sustainability of the virus, and the virus can be transmitted through aerosols of infected patients into the environment The dromedary camel is the only identified animal reservoir to date These animals play important roles in sustaining the virus in certain communities and may act as an amplifier of the virus by secreting it in their body fluids, especially in nasal and rectal discharges MERS-CoV has been detected in the nasal and rectal secretions of infected camels, and MERS-CoV of this origin has full capacity to infect human airway epithelium in both in vitro and in vivo models Other evidence confirms the direct transmission of MERS-CoV from camels to humans, though the role of camel meat and milk products has yet to be well studied Human-to-human transmission is well documented through contact with an active infected patient or some silently infected persons Furthermore, there are some significant risk factors of individuals in close contact with a positive MERS-CoV patient Outbreaks within family clusters have been reported Some predisposing genetic factors favor MERS-CoV infection in some patients, which is worth investigating in the near future The presence of other comorbidities may be another factor Overall, there are many unknown/confirmed aspects of the virus/human/animal network Identification of the exact mechanism of transmission of MERS-CoV from camels to humans and searching for new reservoir/s are of high priority This will reduce the shedding of the virus into the environment, and thus the risk of human infection can be mitigated Acknowledgment: This work was funded by a grant from the King Abdul-Aziz City for Science and Technology (KACST), (Grant no: 24-1) through the MERS-CoV research grant program, which is a part of the National Transformation Plan (NTP) Copyright © 2020

First Observations of Cosmic Ray Neutrons by a Mini Neutron Monitor at Riyadh, Saudi Arabia

In April 2017, a mini neutron monitor (NM) was installed at King Abdulaziz City for Science and Technology (KACST) central Saudi Arabia (Riyadh; cut-off rigidity, Rc = 14.4 Gv) for continuous observation of the cosmic ray (CR) neutrons. The detector was built as a major aspect of the international scientific joint effort between the Centre of Space Research (North-West University, Potchefstroom, South Africa) and KACST. The recorded data correspond to low energy neutrons that primarily have energies lower than 20 GeV. In this paper, a brief description about the mini NM detector will be given. The influence of atmospheric pressure on the recorded CR neutrons was studied and the barometric coefficient was calculated and used to eliminate the pressure effects from the measured data. The obtained coefficient was consistent with those previously obtained by several investigators. The daily variation of the CR neutron was studied and characterized. Short-term CR periodicities, such as the 27-day period, and its two harmonics, were identified. The obtained periodicities are in agreement with those reported by different researchers. The obtained results from this detector have been compared to the existing 1 m2 scintillator detector showing comparable results. Long-term data from this detector will be of incredible significance to the research community to investigate several types of CR variations resulting from solar activity at such high cut off rigidity site.

Atmospheric effects on secondary cosmic ray muons observed by multi-wire muon detector at a high cutoff rigidity station

In October 2017, a multi-layer small multi-wire (MW) detector for cosmic ray (CR) muon measurements was installed at King Abdulaziz City for Science and Technology (KACST), Riyadh, Saudi Arabia (Rc = 14.4 GV). This detector is considered to be the first of its kind used for long term CR measurements. In this study, CR data collected from KACST-MW detection system and radiosonde measurements were used to investigate the effect of atmospheric pressure, ground temperature, height of the muon production layer, temperature at that layer, and temperature weighted by atmospheric mass, on CR muons. Regression analyses between the observed muon count rate and these variables were carried out and the corresponding coefficients were obtained and used to correct the observed muon count rate for the temporal variation of these variables. The effect of the atmospheric pressure was conducted first and used to correct the data for this effect. The pressure corrected count rate is anti-correlated with the height of muon production, ground temperature, and atmospheric mass-weighted temperature. On the other hand, the temperature at the muon production layer is positively correlated with the muon count rate. The obtained results from this study are in good agreement with those reported by several researchers. Taking advantages of the relationship between the detected CR muons and the temperature at the muon production layer (stratospheric temperature), this relationship is inverted to calculate this temperature from muon observations. The proposed technique provides excellent predictability of the stratospheric temperatures.

Prevalence of MERS-CoV in Healthy Adults in Western Saudi Arabia, 2011-2016; a Retrospective, Cross-Sectional Seroepidemiological Study

Background: MERS-CoV is a newly recognized zoonotic coronavirus. Current evidence confirms the role of dromedaries in primary human cases but does not explain sporadic community cases. However, asymptomatic or subclinical cases could represent a possible source of infection in the community. Therefore, we investigated the seroprevalence of MERS-CoV in the general population of the western region of Saudi Arabia. Methods: Archived human sera (7,461) collected between 2011 and 2016 from healthy adult blood donors from 50 different nationalities in the western part of Saudi Arabia were obtained. Samples were tested for MERS-CoV S1-specific antibodies (Abs) by ELISA and confirmed by testing for neutralizing Abs (nAbs) using both pseudotyped and live virus neutralization assays. Findings: Out of 7,461 samples, 174 sera from individuals with 18 different nationalities were ELISA positive (2·3%, 95% CI 2·0-2·7). Presence of nAbs was confirmed in 17 samples (0·23%, 95% CI 0·1-0·4) of which one sample exhibited positivity in both neutralization assays. Confirmed seropositivity was identified in young (15-44 years) Middle Eastern men and women from Saudi Arabia, Egypt, Yemen, Pakistan, Palestine, Sudan, and India without significant preference. Interpretation: An increasing trend of unreported MERS-CoV seroprevalence was observed in the general population in western Saudi Arabia, suggesting that asymptomatic or mild infections might exist and act as an unrecognized source of infection. Seropositivity of individuals from different nationalities underscores the potential MERS exportation outside of the Arabian Peninsula. Thus, enhanced and continuous surveillance is highly warranted. Funding Statement: King Abdulaziz City for Science and Technology (KACST), Riyadh, Saudi Arabia (grant number 09-1). Declaration of Interests: The authors declare no competing interests. Ethics Approval Statement: Ethical approval was obtained from the Unit of Biomedical Ethics in King Abdulaziz University Hospital. Before starting the study, all samples were anonymized using serial numbers.

Tunable Dual-Wavelength Self-injection Locked InGaN/GaN Green Laser Diode

Authors acknowledge the support from King Fahd University of Petroleum & Minerals (KFUPM); King Abdulaziz City for Science and Technology (KACST), (grant nos. EE2381 and KACST TIC R2-FP-008); Partial support from King Abdullah University of Science and Technology (KAUST) baseline funding (grant nos. BAS/1/1614-01-01, KCR/1/2081-01-01, and GEN/1/6607-01-01); and KAUST-KFUPM Special Initiative (KKI) Program (REP/1/2878-01-01).

Unleashing the potential of molecular beam epitaxy grown AlGaN-based ultraviolet-spectrum nanowires devices

We acknowledge the financial support from the King Abdulaziz City for Science and Technology (KACST) under Grant No. KACST TIC R2-FP-008. This work was partially supported by the King Abdullah University of Science and Technology (KAUST) baseline funding No. BAS/1/1614-01-01 and MBE equipment funding No. C/M-20000-12-001-77.