This study's aim was to determine the pesticide residues in 10 different vegetable commodities from the Asir region, Saudi Arabia. We evaluated 211 vegetable samples, collected from supermarkets between March 2018 and September 2018, for a total of 80 different pesticides using ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS) after extraction with a multi-residue method (the QuEChERS method). The results were assessed according to the maximum residue limit (MRL) provided by European regulations for each pesticide in each commodity. All lettuce, cauliflower, and carrot samples were found to be free from pesticide residues. A total of 145 samples (68.7%) contained detectable pesticide residues at or lower than MRLs, and 44 samples (20.9%) contained detectable pesticide residues above MRLs. MRL values were exceeded most often in chili pepper (14 samples) and cucumber (10 samples). Methomyl, imidacloprid, metalaxyl, and cyproconazole were the most frequently detected pesticides. Based on the results of this study, we recommend that a government-supported program for the monitoring of pesticide residues in vegetables be established to promote consumers' health and achieve sustainable farming systems. Author Contributions: M.F.A.R.: Ideas; formulation and evolution of overarching research goals and aims. M.M.A.A.-H.: Performing the experiments, instrumentation and data interpretation, application of statistical and computational techniques to analyze and study data. M.M.F.A.: Application of statistical, mathematical, computational, and other formal techniques to analyze or synthesize study data, or data/evidence collection. H.A.A.: Management activities to annotate (produce metadata), scrub data and maintain research data. M.A.A.: Conducting a research and investigation process. Provision of study materials, laboratory samples. A.A.S.: Application of statistical, mathematical, computational, and other formal techniques to analyze or synthesize study data. H.A.S.: Development and design of methodology; creation of models. N.S.A.: Acquisition of the financial support for the project leading to this publication. Management and coordination responsibility for the research activity planning and execution. All authors have read and agreed to the published version of the manuscript.

The aim of this study is to characterise the neutron flux generated directly behind targets used in medical cyclotrons. The characterisation process aims at determining the feasibility of using the generated neutrons for research purposes in neutron activation analysis. The study was performed by activating gold foils placed directly behind the cyclotron targets. The thermal and epithermal neutron flux were found to be 4.5E+05 ± 8.78E+04 neutrons cm−2 s−1 and 2.13E+06 ± 8.59E+04 neutrons cm−2 s−1, respectively. The flux value is the same order of magnitude listed in the manual produced by the cyclotron manufacturer. The results are encouraging and show high potential for using the cyclotron facility as a thermal neutron source for research purposes. However, it is important radiation protection procedures be followed to ensure the safety of researchers due to the high gamma dose rate measured directly behind the target at 2.46 Sv/h using an OSL chip during the beam on time.

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