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Abstract Background The rising demand for improved aesthetics has driven the utilization of recently introduced aesthetic materials for creating custom post and core restorations. However, information regarding the fracture resistance of these materials remains unclear, which limits their practical use as custom post and core restorations in clinical applications. Aim of the study This study aimed to evaluate the fracture resistance of three non-metallic esthetic post and core restorations and their modes of failure. Materials and methods Thirty-nine single-rooted human maxillary central incisors were endodontically treated. A standardized post space preparation of 9mm length was performed to all teeth to receive custom-made post and core restorations. The prepared teeth were randomly allocated to receive a post and core restoration made of one of the following materials (n=13): glass fiber-reinforced composite (FRC), polyetheretherketone (PEEK) and polymer-infiltrated ceramic-network (PICN). An intraoral scanner was used to scan all teeth including the post spaces. Computer-aided design and computer-aided manufacturing (CAD-CAM) was used to fabricate post and core restorations. Post and core restorations were cemented using self-adhesive resin cement. All specimens were subjected to fracture resistance testing using a universal testing machine. Failure mode analysis was assessed using a stereomicroscope and SEM. The data was statistically analyzed using One-Way ANOVA test followed by multiple pairwise comparisons using Bonferroni adjusted significance level. Results Custom PEEK post and core restorations displayed the least fracture load values at 286.16 ± 67.09 N. In contrast, FRC exhibited the highest average fracture load at 452.60 ± 105.90 N, closely followed by PICN at 426.76 ± 77.99 N. In terms of failure modes, 46.2% of specimens with PICN were deemed non-restorable, while for PEEK and FRC, these percentages were 58.8% and 61.5%, respectively. Conclusions Within the limitation of this study, both FRC and PICN demonstrated good performance regarding fracture resistance, surpassing that of PEEK.

This study aimed to investigate the perceptions of primary and secondary students' parents in Jordan toward the distance learning process implemented in light of the coronavirus disease (COVID-19) pandemic. To achieve the study objectives, the researchers used the descriptive survey method to collect and analyze data and interpret the results. After developing the study instrument (questionnaire) and ensuring its validity and reliability, it was distributed to a selected sample, consisting of 470 parents, by random cluster method during the second semester of the 2019-2020 academic year. The study results show that primary and secondary students' parents were moderately satisfied with the distance learning process implemented in light of the COVID-19 pandemic. In addition, the results reveal statistically significant differences in the parents' perceptions attributed to the variables of the child's grade, in favor of grades 5-7; teacher's gender, in favor of female teachers; and school type, in favor of private schools.

Abstract Background Tubal patency testing is an essential part of female subfertility evaluation. Hysterosalpingogram is less invasive and less expensive compared to laparoscopy and dye testing (LDT), i.e., laparoscopic chromopertubation. Hysterosalpingo-foam sonography (HyFoSy) uses commercial echogenic gel foam that is easily visible on ultrasound to assess the tubes. It offers a safer and less painful alternative to HSG, with no radiation exposure. Hysterosalpingo-lidocaine-foam sonography with power Doppler (HyLiFoSy-PD) uses lidocaine-made gel foam as a contrast medium. It was postulated to as to be less painful and easier to detect on ultrasound, compared with hysterosalpingo-foam sonography using other contrast media and that it can also be used whenever the commercial gel used with HyFoSy is not available or is relatively expensive. Methodology This prospective diagnostic accuracy study was carried out between February 2018 and 2020 at the Cairo Fetal Medicine Unit, Department of Obstetrics and Gynecology, Cairo University. One hundred twenty-two infertile patients, who were already scheduled for LDT as a part of their infertility work-up, were consecutively recruited for this study. The HyLiFoSy-PD (index test) was performed 1 week before the scheduled LDT for these patients. Using an intrauterine pediatric Folley’s balloon catheter, 20 ml of lidocaine-made gel foam was slowly infused intrauterine, while observing their flow in both fallopian tubes using a grayscale and power Doppler transvaginal two-dimensional ultrasound system. All patients then underwent LDT (reference test). The results of HyLiFoSy-PD were compared with those of LDT to determine the accuracy of HyLiFoSy-PD in tubal patency assessment. We also assessed the procedure duration, associated pain, and other complications. Results Comparing HyLiFoSy-PD with LDT in the 115 patients who completed the procedure, results showed 98.1% sensitivity, 90% specificity, 99% positive predictive value, 81.8% negative predictive value, 9.81 positive likelihood ratio, 0.02 negative likelihood ration, and 97.4% overall accuracy in the assessment of tubal patency (odds ratio = 463.5 with confidence interval = 79.39–2706; P-value: 0.687). The median procedure duration was 11 min. All patients experienced some degree of pain during the procedure with 91 patients (79%) reported mild pain and 24 patients (21%) reported moderate pain. Conclusion HyLiFoSy-PD was found to be an accurate tool in tubal patency assessment. It was also found to be safe and well-tolerated.

Heterogeneity in the Internet of Things (IoT) environment is a critical issue for supporting security and privacy.IoT environment has become an open invitation to hackers to control and attack connected IoT devices. So, it has become essential to face security issues & challenges in IoT due to IoT applications' rapid development. Program Analysis (PA) is a method that focuses on defending against attacks on the systems implemented to detect malware applications. It is also responsible for adequately analyzing applications' behavior to provide security and privacy. This survey has been introduced carefully based on the systematic literature reviews (SLR) guidelines to provide a survey and taxonomy of the PA with its related topics: the sensitivity of analysis and characteristics of analysis. It presents a new classification of PA techniques. This classification has been created by examining the implemented security analysis systems (SAS) that detect various malware applications. More importantly, this survey presents the three types of SAS that used PA methods for the first time. Also, the related surveys, the performance metrics of PA and IoT Security Issues and Challenges have been discussed. Finally, future directions of the PA have been discussed.

The International Maritime Organization (IMO) aims to reduce greenhouse gas (GHG) emissions by 40% by 2030 compared with 2008. The carbon intensity indicator (CII) calculates the annual reduction factor required to continuously improve a ship's operational carbon intensity at a specific rating level. Verification and documentation of the achieved annual operational CII against the prescribed target are necessary to establish the operational carbon intensity rating. This study focuses on the intricate process of data collection for CII within the oil shipping industry, targeting engineering departments and shipboard management teams. Against the backdrop of the industry's substantial carbon dioxide emissions, the IMO has mandated the calculation of CII values for ships exceeding 5000 gross tons to promote sustainability and reduce environmental impact. We have collected emission data of 20 oil tankers over a period of 2 years using our ship maintenance and operating system (SMOS) and analyzed the data to compare the CII ratings. Our results indicate that a staggering ~63% of the vessels had the lowest CII rating of category E. It is therefore crucial to properly collect, organize, and evaluate data for CII calculation and take necessary measures to improve rating. This paper provides a deeper insight into the evolving CII calculation methodology, emphasizing the incorporation of correction factors and exclusions, and delineates the essential data collection practices needed to facilitate accurate CII calculations. [ABSTRACT FROM AUTHOR]

The shipping industry is facing a shortage of seafarers and a high turnover rate which highlights the critical importance of seafarers’ job satisfaction and commitment. This study investigates the intricate relationships among organisational justice, job satisfaction, and organisational commitment among seafarers working in international merchant vessels. This study specifically examines the impact of organisational justice, which encompasses distributive justice (DJ), procedural justice (PJ), and interactional justice (IJ), on organisational commitment with the mediating role of job satisfaction of international seafarers. Utilising a unique dataset from 211 seafarers representing major seafaring nationalities, this study employs structural equation modelling (SEM) to analyze the relationships. The findings of this study shed light on how seafarers’ perceptions of equality and fairness in resource distribution, management policies and procedures, and the quality of interpersonal treatment affect their job satisfaction and, in turn, their commitment to their employing organisations. This study uses a unique data set collected from seafarers from the major seafaring nations that has not been done in previous studies. Moreover, this study, for the first time, includes all three dimensions of organisational justice and explores their impact on the overall justice perception of seafarers. [ABSTRACT FROM AUTHOR]

In this article, a dual-band bandpass microstrip filter (DBBPF) is suggested and studied for RF/microwave applications. Our filter design method is based on two basic concepts; the use of metamaterial resonators in C-shaped split rings (C-SRR) to have the left-handed behavior (LH) with minimized losses and the feed by a microstrip line of significant length folded for the desired miniaturization. The two C-SRRs are optimized for a size of 6 × 3 mm² to cover the desired frequency bands and the two feed lines have a length of 37.1 mm to ensure the necessary adaptation. The search of a strong electromagnetic coupling between the two C-SRRs and the feed lines allowed us to choose the best position to place our resonators in the filter. The simulation of the filter parameters for two different proposed configurations shows two different qualities. According to the simulation outcomes for the two proposed filter configurations, two kinds of frequency response were obtained with different characteristics. For the first configuration where the two C-SRRs are separated by the folded arms of the two feed lines, the filter response is not clear. Contrary to that, the frequency response of the filter is desirable for the second configuration. The suggested filter which is represented by the second configuration has covered both bands (5.88 to 6.39 GHz and 10.75 to 11.16 GHz) for band-pass behavior. In addition, the analysis of the dispersion diagram allowed us to select the electromagnetic behavior associated with each band. [ABSTRACT FROM AUTHOR]

Printed antenna technology gained has become centre of attraction for designing MIMO antenna system for future communication applications. Antenna is an essential component for 5G communication system. MIMO technology is highly preferrable due to high data rate and simultaneous data transmission establishment. In this article, a curved slot incorporated circular shaped antenna is constructed and tested for performance utilizing conventional ground planes in an eventual Fifth Generation (5G) mobile communication network. The proposed single element system is operating from 2.6 to 12.9 GHz with an 85.84% efficiency throughout the band. The substrate of the radiator is 30 mm 30 mm 1.6 mm, where a circular patch is used whose size is 9.35 mm. A partial ground structure of 30 mm 10 mm is used to obtain high efficiency and wide bandwidth. The structured antenna system has a maximum directivity of 4.8, efficiency of 89%, and maximum gain of 1.68 dB which are desired in any MIMO system to tolerate interference and maintain user bandwidth. The proposed micro strip patch two element antenna covers 10 dB return loss frequencies from 2.6 GHz to 11.8 GHz than the conventional method. The total size of the MIMO antenna system is 70 mm 60 mm 1.6 mm. The 2-element MIMO antenna simulated results are determined by the HFSS software with their performance. [ABSTRACT FROM AUTHOR]

Because of its qualitative importance in several aspects, especially biomedical ones, the characterization of solid materials has recently attracted the interest of scholars. The detection of such a material based on its dielectric constant with reliable precision represents the main desired objective. In this paper, a miniature sized microwave biosensor is presented for solid materials characterization. The proposed biosensor is formed by two identical and periodic split ring metamaterial resonators (SRRs) fed by a microstrip line adapted to its two extremities. The method proposed for the design of our biosensor is based on the exploitation of the electromagnetic qualities of each SRR representing the unit cell of the overall structure. The size of the SRR is optimized for electrical dimensions of 0.2512 × 0.225120 × 0.031λο where λο is the free space wavelength calculated at the lowest operating frequency of 4.72 GHz. the characterization of solid materials is based on the detection of its dielectric constants through direct contact with the proposed biosensor. For our study, we have used four different substrates to have the different sensitivities. The simulations carried out on the overall structure (biosensor and dielectric substrate) based on the HFSS numerical simulator showed good sensing performance of our biosensor. A low full width at half maximum (FWHM = 0.004), A high quality factor (Q = 103.28) and a high figure of merit (FOM = 428.61). These features can make our biosensor more reliable for solids materials sensing. [ABSTRACT FROM AUTHOR]

Mainul Haque,1 Tariqul Islam,2 Nor Azlina A Rahman,3 Judy McKimm,4 Adnan Abdullah,5 Sameer Dhingra6 1Unit of Pharmacology, Faculty of Medicine and Defence Health, Universiti Pertahanan Nasional Malaysia, (National Defence University of Malaysia), Kuala Lumpur 57000, Malaysia; 2UChicago Research Bangladesh, Dhaka 1230, Bangladesh; 3Department of Physical Rehabilitation Sciences, Kulliyyah of Allied Health Sciences, International Islamic University Malaysia, Kuantan, 25200, Malaysia; 4Swansea University School of Medicine, Swansea University, Swansea, Wales SA2 8PP, UK; 5Unit of Occupational Medicine, Faculty of Medicine and Defence Health, Universiti Pertahanan Nasional Malaysia, (National Defence University of Malaysia), Kuala Lumpur 57000, Malaysia; 6School of Pharmacy, Faculty of Medical Sciences, The University of the West Indies, St. Augustine Campus, Mount Hope, Trinidad & TobagoCorrespondence: Mainul HaqueFaculty of Medicine and Defence Health, Universiti Pertahanan Nasional Malaysia, (National Defence University of Malaysia), Kem Perdana Sungai Besi, Kuala Lumpur 57000, MalaysiaTel +60 1092 65543Email runurono@gmail.comAbstract: The prevalence of long-term (chronic) non-communicable diseases (NCDs) is increasing globally due to an ageing global population, urbanization, changes in lifestyles, and inequitable access to healthcare. Although previously more common in high- and upper-middle-income countries, lower-middle-income countries (LMICs) are more affected, with NCDs in LMICs currently accounting for 85– 90% of premature deaths among 30– 69 years old. NCDs have both high morbidity and mortality and high treatment costs, not only for the diseases themselves but also for their complications. Primary health care (PHC) services are a vital component in the prevention and control of long-term NCDs, particularly in LMICs, where the health infrastructure and hospital services may be under strain. Drawing from published studies, this review analyses how PHC services can be utilized and strengthened to help prevent and control long-term NCDs in LMICs. The review finds that a PHC service approach, which deals with health in a comprehensive way, including the promotion, prevention, and control of diseases, can be useful in both high and low resource settings. Further, a PHC based approach also provides opportunities for communities to better access appropriate healthcare, which ensures more significant equity, efficiency, effectiveness, safety, and timeliness, empowers service users, and helps healthcare providers to achieve better health outcomes at lower costs.Keywords: primary health care, PHC, prevention, control, chronic, long-term conditions, non-communicable diseases, NCDs, lower-middle-income countries, LMICs