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The design and configuration of a multi-layered imaging system with the ability to detect thermal neutrons, fast neutrons and gamma rays has been developed and its efficacy demonstrated. The work presented here numerically determines the systems efficiency and spatial resolution, using 252Cf and 137Cs as a case study. The novelty of this detection system lies in the use of small form factor detectors in a three-layer design, which utilises neutron elastic scattering and Compton scattering simultaneously. The current configuration consists of 10 mm thick natural lithium glass (GS10) scintillator integrated with a 20 mm thick plastic scintillator (EJ-204) in the first layer, a 15 mm thick lithium glass (GS10) scintillator in the second and a 30 mm thick CsI(Tl) scintillator forming the final layer. Each of these layers is backed with an 8 x 8 silicon photomultiplier diode (SiPM) array. The overall size of the imaging system is 27 mm x 27 mm x 135 mm. MCNPv6.1 and Geant4-10.04 were alternatively used to optimise the overall configuration and to investigate detection modalities. Results show promising performance with high precision source localisation and characterization abilities. Measurements were virtually obtained of two gamma-ray sources within steel enclosures at angles of 15°, 30° and 50° separation in order to test spatial resolution ability of the system. With the current active size of the system and the 8x8 SiPM configuration, the results estimate the spatial resolution to be close to 30°. The ability of the system to characterise and identify sources based on the type and energy of the radiation emitted, has been investigated and results show that for all radiation types the system can identify the source energy within the energy range of typical reported sources in literature.

Introduction: in Oman, there is a need to understand the profile of primary care physicians' (PCP) knowledge, attitude, and practice, and barriers (KAPB) towards tobacco dependence treatment (TDT). Their profile will directly affect their consultation and contribution to health care educators to develop an appropriate educational program for the PCPs. The aim of this study is to determine profiles in a cohort of PCP with regards to factors associated with physicians' perceived KAPB of providing TDT., Methods: a cross-sectional survey was conducted for four months from September to December 2019. A sample of 226 (response rate is 71.2%) PCPs working for Muscat's health centers, the capital of Oman, was collected. A 2-step cluster method was used to separate the sample into sub-groups according to their demographic and KAPB scores., Results: cluster analysis revealed two groups of PCPs who are different in demographics and KAPB scores. The PCPs in cluster B (27.4%) have higher educational levels, senior ranking, more males and older. They labeled as the "good knowledge, positive attitudes, and highly practices" group. The PCPs in cluster A comprised 72.6% of our samples. There are more females, younger, and with a junior ranking. This cluster was identified as the "lack of knowledge, moderate attitudes, and rarely practices" group., Conclusion: findings might help primary health care authorities to address this preventable issue and plan interventions to establish well-structured TDT clinics in the future., Competing Interests: The authors declare no competing interests., (Copyright: Moon Fai Chan et al.)

Global concern for the illicit transportation and trafficking of nuclear materials and other radioactive sources is on the rise, with efficient and rapid security and non-proliferation technologies in more demand than ever. Many factors contribute to this issue, including the increasing number of terrorist cells, gaps in security networks, politically unstable states across the globe and the black-market trading of radioactive sources to unknown parties. The use of passive gamma-ray and neutron detection and imaging technologies in security-sensitive areas and ports has had more impact than most other techniques in detecting and deterring illicit transportation and trafficking of illegal radioactive materials. This work reviews and critically evaluates these techniques as currently utilised within national security and non-proliferation applications and proposes likely avenues of development.