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Municipal wastewater treatment systems use the chemical oxygen demand test (COD) to identify organic contaminants in industrial effluents that impede treatment due to their high concentration. This study reduced the COD levels in tannery wastewater using a multistage treatment process that included Fenton oxidation, chemical coagulation, and nanotechnology based on a synthetic soluble COD standard solution. At an acidic pH of 5, Fenton oxidation reduces the COD concentration by approximately 79%. It achieves this by combining 10 mL/L of H2O2 and 0.1 g/L of FeCl2. Furthermore, the author selected the FeCl3 coagulant for the coagulation process based on the best results of comparisons between different coagulants. At pH 8.5, the coagulation dose of 0.15 g/L achieved the maximum COD removal efficiency of approximately 56.7%. Finally, nano bimetallic Fe/Cu was used to complete the degradation and adsorption of the remaining organic pollutants. The XRD, SEM, and EDX analyses proved the formation of Fe/Cu nanoparticles. A dose of 0.09 g/L Fe/Cu NPs, 30 min of contact time, and a stirring rate of 200 rpm achieve a maximum removal efficiency of about 93% of COD at pH 7.5. The kinetics studies were analyzed using pseudo-first-order P.F.O., pseudo-second-order P.S.O., and intraparticle diffusion models. The P.S.O. showed the best fit among the kinetic models, with an R2 of 0.998. Finally, the authors recommended that technique for highly contaminated industrial effluents treatment for agriculture or industrial purposes.
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OBJECTIVES: To assess the rate of inappropriate repetition of laboratory testing and estimate the cost of such testing for thyroid stimulating hormone (TSH), total cholesterol, vitamin D, and vitamin B12 tests. METHODS: A retrospective cohort study was carried out in the Family Medicine and Polyclinic Department at King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia. Clinical and laboratory data were collected between 2018-2021 for the 4 laboratory tests. The inappropriate repetition of tests was defined according to international guidelines and the costs were calculated using the hospital prices. RESULTS: A total of 109,929 laboratory tests carried out on 23,280 patients were included in this study. The percentage of inappropriate tests, as per the study criteria, was estimated to be 6.1% of all repeated tests. Additionally, the estimated total cost wasted amounted to 2,364,410 Saudi Riyals. Age exhibited a weak positive correlation with the total number of inappropriate tests (r=0.196, p=0.001). Furthermore, significant differences were observed in the medians of the total number of inappropriate tests among genders and nationalities (p<0.001). CONCLUSION: The study identified significantly high rates of inadequate repetitions of frequently requested laboratory tests. Urgent action is therefore crucial to overcoming such an issue.
Asunto(s)
Atención Terciaria de Salud , Humanos , Estudios Retrospectivos , Femenino , Arabia Saudita , Masculino , Persona de Mediana Edad , Adulto , Atención Terciaria de Salud/estadística & datos numéricos , Procedimientos Innecesarios/estadística & datos numéricos , Procedimientos Innecesarios/economía , Atención Ambulatoria/estadística & datos numéricos , Atención Ambulatoria/economía , Tirotropina/sangre , Anciano , Adulto Joven , Colesterol/sangre , Vitamina B 12/sangre , Vitamina D/sangre , Estudios de Cohortes , Técnicas de Laboratorio Clínico/economía , Técnicas de Laboratorio Clínico/estadística & datos numéricos , Adolescente , Atención Médica Basada en ValorRESUMEN
Background/Aims: The most common cancer among men and the third most common among women in Saudi Arabia is colon cancer. This study aimed to evaluate the yield of the fecal occult blood test (FOBT) used as a screening tool for colon cancer. Settings and Design: Medical records of all patients above the age of 50 years who had visited the Family Medicine clinic at King Faisal Specialist Hospital and Research Centre in Riyadh, Saudi Arabia and who had undergone the FOBT screening between January 2002 and March 2017 were retrospectively reviewed. Materials and Methods: We collected patients' demographic data, FOBT results, and colonoscopy pathology reports results. Statistical Analysis: Data were analyzed using the Statistical Package for Social Science Version 25 (IBM Corp., Armonk, NY, USA). Results: We included 2179 patients in this study. The mean age was 59.8 ± 8 years. As a result of the FOBT screening, 19.7% of the patients had a positive FOBT. Colon cancer accounted for 3.5% of all abnormal colonoscopy pathology reports. The Saudi age-standardized incidence rate (ASIR) in our study was 26.56 per 100,000 persons. Conclusion: FOBT is a feasible tool that can be used for colon cancer screening in primary care settings. The Saudi ASIR in our study was higher than the Saudi Cancer Registry, but it was still lower in comparison to other countries. We recommend the establishment of a national community-based colon cancer screening program.