During the operation of an X-ray machine, if the radiation protection of X-ray room is insufficient, not only the patient but also clinical staffs as well as public are exposed to high X-ray exposures. In this researc...During the operation of an X-ray machine, if the radiation protection of X-ray room is insufficient, not only the patient but also clinical staffs as well as public are exposed to high X-ray exposures. In this research work, leakage and scattered radiations were measured from X-ray machine in the radiology department of Cape Coast Teaching hospital in the Cape Coast Municipality of Ghana. The scattered radiation exposures of X-rays in some selected areas within the facility were measured. The X-ray machine was operated for a range of kilo voltage peaks of kVp 77, 70, 63 and 66 with intensities 20, 6.3 and 8.0 mAs, which represents the main technique factors of some body parts such as chest, lumbar spine and extremities during radiographic examinations. The measurements were performed using a RADOS-120 Universal survey meter. The radiation doses rates measured in the various locations in the Radiology Department of Cape Coast Teaching Hospital of Ghana were in the range of 0.10 μSv/hr to 0.12 μSv/hr. These values were all within the background measurement of 0.10 μSv/hr. Moreover, there were no risks of high radiation doses to patients, staffs and people visiting the X-ray department. The results obtained indicated that within the radiology department of the Hospital, all the selected locations were very safe to patients, occupational workers and the general public which could be attributed to adequate shielding in the facility.展开更多
Background:The 2-amino-5-chloro-N,3-dimethylbenzamide is a key intermediate in the synthesis of pesticides and pharmaceuticals.However,no literature currently exists on 2-amino-5-chloro-N,3-dimethylbenzamide poisoning...Background:The 2-amino-5-chloro-N,3-dimethylbenzamide is a key intermediate in the synthesis of pesticides and pharmaceuticals.However,no literature currently exists on 2-amino-5-chloro-N,3-dimethylbenzamide poisoning in humans.This study aimed to reveal the health hazard of this chemical for humans and summarize the clinical characteristics of patients with occupational 2-amino-5-chloro-N,3-dimethylbenzamide poisoning.Methods:This observational study included four patients with 2-amino-5-chloro-N,3-dimethylbenzamide poisoning from June 2022 to July 2022.The entire course of the incidents was described in detail.Blood 2-amino-5-chloro-N,3-dimethylbenzamide concentrations were detected by a mass spectrometer.Hema-toxylin and eosin staining was performed to assess liver injury,and immunofluorescence was used to evaluate hepatic mitophagy.Results:The 2-amino-5-chloro-N,3-dimethylbenzamide powder(99%purity)entered the human body mainly via the skin and respiratory tract due to poor personal protective measures.The typical course of 2-amino-5-chloro-N,3-dimethylbenzamide poisoning was divided into latency,rash,fever,organic dam-age,and recovery phases in accordance with the clinical evolution.Rash and fever may be the important premonitory symptoms for further organ injuries.The chemical was detected in the blood of all patients and caused multiple organ injuries,predominantly liver injury,including kidney,myocardium,and micro-circulation.Three patients recovered smoothly after comprehensive treatments,including artificial liver therapy,continuous renal replacement therapy,glucocorticoids,and other symptomatic and supportive treatments.One patient survived by liver transplantation.The postoperative pathological findings of the removed liver showed acute liver failure,and immunofluorescence staining confirmed the abundance of mitophagy in residual hepatocytes.Conclusions:This study is the first to elaborate the clinical characteristics of patients with 2-amino-5-chloro-N,3-dimethylbenzamide poisoning.The chemical enters the body through the respiratory tract and skin during industrial production.The 2-amino-5-chloro-N,3-dimethylbenzamide poisoning causes multiple-organ dysfunction with a predominance of liver injury.Liver transplantation may be an effective option for patients with severe liver failure.The mechanisms of liver injury induced by 2-amino-5-chloro-N,3-dimethylbenzamide might involve abnormal mitochondrial function and mitophagy.展开更多
This study was carried out to analyze individual annual dose records of diagnostic radiology staff at forty-eight (48) different medical facilities in urban and rural Region of Ghana for the period of 2011-2015. The m...This study was carried out to analyze individual annual dose records of diagnostic radiology staff at forty-eight (48) different medical facilities in urban and rural Region of Ghana for the period of 2011-2015. The monitored dose data were extracted from the Radiation Protection Institute of the Ghana Atomic Energy Commission’s database called the Dose Management System (DMS). The doses of these OEWs analyzed, are divided into four subgroups namely;general radiographers, radiologists, computed tomography (CT) technologists, fluoroscopy technologists. The dose distribution, collective dose and mean annual dose were determined. A total of 1574 OEWs were monitored comprising of 56% radiographers, 15% radiologist, 21% computed tomography (CT) technologists and 8% fluoroscopy technologists. The average annual effective dose ranged from 0.36 to 1.70 mSv with radiographers receiving the largest. Fluoroscopy technologist recorded the least annual total collective effective dose value of 0.1 person-Sv. The study contributes to the existing works to promote a more comprehensive personal monitoring service for OEWs. Continued analysis of occupational doses should be an integral component of institutional radiation safety programs in Ghana.展开更多
Body Mass Index (BMI) and Percentage Body Fat (%BF) values have been determined in cancer patients. In the study, 83 adult cancer patients were assessed of which 15 (18.1%) were males and 68 (81.9%) females. Body weig...Body Mass Index (BMI) and Percentage Body Fat (%BF) values have been determined in cancer patients. In the study, 83 adult cancer patients were assessed of which 15 (18.1%) were males and 68 (81.9%) females. Body weight and height of individual patients were used in calculating their respective BMI values. The respective %BF values were determined taking into consideration of the age, gender and BMI. Maximum values of BMI (34.71 kg/m2) and %BF (46.37%) were obtained, for which they were females and the minimum values of BMI (12.08 kg/m2) and %BF (12.35%) respectively. The patient with the minimum %BF value was male and that of BMI was female. It was observed from the results that females have higher values of both BMI and %BF than their male counterparts. The study reveals higher rate of female cancer incidence than males.展开更多
The scientific studying of kissing is known as Philematology. This originates from the Greek word PHILOS in the ancient days meaning earthly. The study of kissing shows you what kissing means and its place in various ...The scientific studying of kissing is known as Philematology. This originates from the Greek word PHILOS in the ancient days meaning earthly. The study of kissing shows you what kissing means and its place in various cultures. (Lana Citron 2010, a Compendium of Kisses), and the difference between Simple Kiss versus Passionate kiss. In simple kisses only 2 muscles are involved. While in passionate kisses there may be about 23 - 34 facial muscles and 112 postural muscles involved. What you can tell from even the simplest of kisses. From the book I Love You. Now What? During kissing, a lot of chemical reactions take place in the brain and the body as a whole. The part of the brain in which these chemicals are secreted is the pituitary gland, where oxytocin, serotonin and dopamine are secreted. The oxytocin which is also sometimes referred to as the cuddle hormone or the love hormone aids in social bonding. It is produced in the hypothalamus and secreted into the bloodstream by the posterior pituitary gland. Oxytocin is released when the cells are excited. Oxytocin can also be referred to aid carbetocin, manufactured version, Pitocin, alpha-hypophamine and syntocinon. It is a team player in social behaviour and mother-infant bonding. The serotonin which is also known as a “happy hormone” is an important chemical and a neurotransmitter in the human body serves as a hormonal modulator that is serotonin aids regulating an individual kissing pattern, sleeping pattern, aggressive pattern, appetite and digestion pattern, memory and mood pattern and sexual pattern. Finally, the dopamine which is also known as a “happy hormone” is a monoamine neurotransmitter which belongs to the catecholamine family that is made up of epinephrine, norepinephrine and dopamine. This dopamine helps an individual to enjoy the act of kissing.展开更多
A lutetium 177 (<sup>177</sup>Lu) radiopharmaceutical has been used as a theragnostic agent in molecular radiotherapies. This study aimed to produce images simulating those obtained in a total body imaging...A lutetium 177 (<sup>177</sup>Lu) radiopharmaceutical has been used as a theragnostic agent in molecular radiotherapies. This study aimed to produce images simulating those obtained in a total body imaging study with hot lesions to assess and investigate the image quality of the Hawkeye SPECT/CT images from Lu-177. The NEMA image quality phantom (PTW) with spheres (inner diameters of 10, 13, 17, 22, 28 and 37 mm) and lung insert was used. The measured volume in the background of the current phantom setting was 9482 mL. The five smaller spheres were filled with an activity concentration of 0.461 MBq/mL and the biggest sphere was filled with water. The phantom was placed on the couch and scanned at four hot sphere-to-background concentrations, which are no background, 16:1, 8:1 and 4:1. The images obtained from the scans were imported onto the OXIRIS image analysis tool. Regions of interest (ROIs) were drawn on each sphere of the reconstructed SPECT image. Image contrast and background variability ratios for hot spheres were used as measures of image quality. In addition, the accuracy of corrections were determined from the uniform background and cold lung insert regions. The 37 mm cold sphere had the highest percent contrast, whiles the 10 mm hot sphere had the least for the various hot sphere to background ratios. The background variability for each hot sphere was also determined. The average lung residual error was calculated to be 23.13% for the 16:1 and 22.57% for both the 8:1 and 4:1 hot sphere to background ratio. The results show that the scanner has very good overall performance.展开更多
Thermoplastic immobilizing masks have dosimetric effects on the patient’s skin dose. The thermoplastic percentage depth dose (PDD), equivalent thickness of water for the masks and surface doses were determined. The s...Thermoplastic immobilizing masks have dosimetric effects on the patient’s skin dose. The thermoplastic percentage depth dose (PDD), equivalent thickness of water for the masks and surface doses were determined. The surface dose factors due to the thermoplastic mask was found to be 1.7949, 1.9456, 2.0563, 2.1967, 2.3827, 2.5459 and 2.6565 for field sizes of 5 × 5, 8 × 8, 10 × 10, 12 × 12, 15 × 15, 18 × 18 and 20 × 20 cm<sup>2</sup> respectively which shifted the percentage depth dose curve to lower values. The physical thermoplastic thickness was measured to be between 2.30 and 1.80 mm, and the equivalent thicknesses of water, d<sub>e</sub>, were determined to be between 1.2 and 1.00 mm. This meant that, as the mask thickness decreased, its water equivalent thickness also decreased. The presence of the mask material increased the skin dose to a factor of 1%. The thermoplastic mask factor was also found to be 0.99.展开更多
This study was done to quality assure the Hawkeye SPECT/CT at the St. Olav’s hospital and create a clinical method for doing individual dosimetry with <sup>177</sup>Lu-octreotate in targeted radionuclide ...This study was done to quality assure the Hawkeye SPECT/CT at the St. Olav’s hospital and create a clinical method for doing individual dosimetry with <sup>177</sup>Lu-octreotate in targeted radionuclide therapy for neuroendocrine tumors. Various quality control parameters were performed on Infinia Hawkeye SPECT/CT. A calibration dose of 160% ± 2% MBq was ordered and first calibrated for all the dose calibrators. The uniformity test was obtained using a 40 MBq Tc-99m point source positioned 2.5 m away from the two detectors. A 200 MBq Tc-99m was diluted in 70 ml of water, dispersed in six syringes for the registration test. A Lu-177 point source was placed in front of the detectors, one at a time, to check the energy peaks. The Jaczczak phantom with a hollow sphere set (volumes: 0.5, 1, 2, 4, 8, and 16) ml with an additional 60 ml sphere was used for the 3D sensitivity and recovery with Lu-177. Total activity of 945.3 MBq was added to 160 ml of water yielding an activity concentration of 5.908 MBq/ml in the spheres. The phantom was then scanned at various time intervals. A cylindrical phantom with a volume of 6283 ml was also used to obtain the cross-calibration measurement (cps/MBq). Total activity of 995.6 MBq was added and the phantom was scanned at days 0, 6, 13 and 23. The dose calibration factor was changed from 762 to 760 to achieve correct doses. The 2D mean sensitivity factor was 5.56 cps/MBq. Uniformities for both detectors were approved after iteration calibration of the PM tubes. The X-ray to SPECT registration was found to be accurate and within specifications. The energy peak test revealed off-centered 208 keV energy peaks for the two detectors. Quality assurance of imaging devices using radiation is essential for radiation protection and ensures a high-quality image.展开更多
Objective:To reveal the effect of boiling time on radionuclide concentrations in seafood by investigating boilingrepresented cooking practices,in order to fill the knowledge gap on how boiling time affects human radia...Objective:To reveal the effect of boiling time on radionuclide concentrations in seafood by investigating boilingrepresented cooking practices,in order to fill the knowledge gap on how boiling time affects human radiation exposure.-Methods:A total of 13 seafood species of four categories(fish,crustacean,mollusk and algae)were collected from the coastal areas of China and analyzed for radionuclide contents left after boiling at 5,10,20 and^(40)min under 100◦C.Grossαandβ,^(40)K,^(226)Ra,^(232)Th,^(137)Cs were measured using the low backgroundαandβcounter and the gamma-spectrometer.Results:The contents of radionuclides decreased significantly with the increasing boiling time.The average retention rate ofα-emitting radionuclide in in fish,crustacean,mollusk,and algae decreased to 64.47%,53.34%,84.12%and 62.63%after 5 min of boiling,respectively,and then to 15.46%,14.21%,71.94%,and 27.27%after^(40)min,respectively.The average retention rate ofβ-emitting radionuclide in in fish,crustacean,mollusk,and algae decreased to 64.89%,43.43%,66.55%and 63.30%after 5 min,respectively,and then to 47.90%,29.01%,45.96%,and 53.24%after^(40)min.The greatest loss of solubility was observed for^(40)K with the average retention rate of 47.16%after 10 min,and higher retention rate of 87.86%and 90.03%in^(226)Ra and^(232)Th,respectively.Conclusion:Boiling is effective in reducing the radionuclide content,with the committed effective dose(CED)reduction of 44.6%achieved by boiling for 10 min,mainly due to the reduction in^(40)K.A full assessment will also be needed to incorporate more radionuclides(^(210)Po,^(210)Pb,^(228)Ra)into the calculations.展开更多
Noise-induced hearing loss(NIHL)has become a global public health problem,and the economic burden of hearing loss caused by noise exposure accounts for 19.6%of the economic burden of all risk factors in the workplace(...Noise-induced hearing loss(NIHL)has become a global public health problem,and the economic burden of hearing loss caused by noise exposure accounts for 19.6%of the economic burden of all risk factors in the workplace(1).The prevalence of occupational NIHL was estimated to be 10%in relevant occupational population in developed countries and 17%–39%(e.g.,textile and petrochemical industries),and 53%–67%(e.g.,cement and automobile industries)in developing countries in Asia,respectively.(2).In China,occupational noiseinduced deafness has become the second primary occupational disease after pneumoconiosis,with the number of reported cases increasing at an average annual rate of 18.68%from 2010 to 2019(3–4).The prevalence of occupational NIHL in the Chinese occupational population was 21.3%,of which 30.2%was related to high-frequency NIHL(an early sign of NIHL)(2).展开更多
Summary What is already known about this topic?Occupational noise-induced hearing loss(NIHL)has been the second most common occupational disease in China.Noise energy is the main risk factor for occupational NIHL.Evid...Summary What is already known about this topic?Occupational noise-induced hearing loss(NIHL)has been the second most common occupational disease in China.Noise energy is the main risk factor for occupational NIHL.Evidence shows the temporal structure of noise(as indicated by kurtosis metric)contribute to the development of NIHL.However,the role of the kurtosis metric in evaluating the risk of occupational NIHL associated with complex noise has been rarely reported.展开更多
文摘During the operation of an X-ray machine, if the radiation protection of X-ray room is insufficient, not only the patient but also clinical staffs as well as public are exposed to high X-ray exposures. In this research work, leakage and scattered radiations were measured from X-ray machine in the radiology department of Cape Coast Teaching hospital in the Cape Coast Municipality of Ghana. The scattered radiation exposures of X-rays in some selected areas within the facility were measured. The X-ray machine was operated for a range of kilo voltage peaks of kVp 77, 70, 63 and 66 with intensities 20, 6.3 and 8.0 mAs, which represents the main technique factors of some body parts such as chest, lumbar spine and extremities during radiographic examinations. The measurements were performed using a RADOS-120 Universal survey meter. The radiation doses rates measured in the various locations in the Radiology Department of Cape Coast Teaching Hospital of Ghana were in the range of 0.10 μSv/hr to 0.12 μSv/hr. These values were all within the background measurement of 0.10 μSv/hr. Moreover, there were no risks of high radiation doses to patients, staffs and people visiting the X-ray department. The results obtained indicated that within the radiology department of the Hospital, all the selected locations were very safe to patients, occupational workers and the general public which could be attributed to adequate shielding in the facility.
基金This work was supported by grants from the Key Research and Development Program of Zhejiang Province(2019C03076)the Fundamental Research Funds for the Central Universities(226-2022-00088).
文摘Background:The 2-amino-5-chloro-N,3-dimethylbenzamide is a key intermediate in the synthesis of pesticides and pharmaceuticals.However,no literature currently exists on 2-amino-5-chloro-N,3-dimethylbenzamide poisoning in humans.This study aimed to reveal the health hazard of this chemical for humans and summarize the clinical characteristics of patients with occupational 2-amino-5-chloro-N,3-dimethylbenzamide poisoning.Methods:This observational study included four patients with 2-amino-5-chloro-N,3-dimethylbenzamide poisoning from June 2022 to July 2022.The entire course of the incidents was described in detail.Blood 2-amino-5-chloro-N,3-dimethylbenzamide concentrations were detected by a mass spectrometer.Hema-toxylin and eosin staining was performed to assess liver injury,and immunofluorescence was used to evaluate hepatic mitophagy.Results:The 2-amino-5-chloro-N,3-dimethylbenzamide powder(99%purity)entered the human body mainly via the skin and respiratory tract due to poor personal protective measures.The typical course of 2-amino-5-chloro-N,3-dimethylbenzamide poisoning was divided into latency,rash,fever,organic dam-age,and recovery phases in accordance with the clinical evolution.Rash and fever may be the important premonitory symptoms for further organ injuries.The chemical was detected in the blood of all patients and caused multiple organ injuries,predominantly liver injury,including kidney,myocardium,and micro-circulation.Three patients recovered smoothly after comprehensive treatments,including artificial liver therapy,continuous renal replacement therapy,glucocorticoids,and other symptomatic and supportive treatments.One patient survived by liver transplantation.The postoperative pathological findings of the removed liver showed acute liver failure,and immunofluorescence staining confirmed the abundance of mitophagy in residual hepatocytes.Conclusions:This study is the first to elaborate the clinical characteristics of patients with 2-amino-5-chloro-N,3-dimethylbenzamide poisoning.The chemical enters the body through the respiratory tract and skin during industrial production.The 2-amino-5-chloro-N,3-dimethylbenzamide poisoning causes multiple-organ dysfunction with a predominance of liver injury.Liver transplantation may be an effective option for patients with severe liver failure.The mechanisms of liver injury induced by 2-amino-5-chloro-N,3-dimethylbenzamide might involve abnormal mitochondrial function and mitophagy.
文摘This study was carried out to analyze individual annual dose records of diagnostic radiology staff at forty-eight (48) different medical facilities in urban and rural Region of Ghana for the period of 2011-2015. The monitored dose data were extracted from the Radiation Protection Institute of the Ghana Atomic Energy Commission’s database called the Dose Management System (DMS). The doses of these OEWs analyzed, are divided into four subgroups namely;general radiographers, radiologists, computed tomography (CT) technologists, fluoroscopy technologists. The dose distribution, collective dose and mean annual dose were determined. A total of 1574 OEWs were monitored comprising of 56% radiographers, 15% radiologist, 21% computed tomography (CT) technologists and 8% fluoroscopy technologists. The average annual effective dose ranged from 0.36 to 1.70 mSv with radiographers receiving the largest. Fluoroscopy technologist recorded the least annual total collective effective dose value of 0.1 person-Sv. The study contributes to the existing works to promote a more comprehensive personal monitoring service for OEWs. Continued analysis of occupational doses should be an integral component of institutional radiation safety programs in Ghana.
文摘Body Mass Index (BMI) and Percentage Body Fat (%BF) values have been determined in cancer patients. In the study, 83 adult cancer patients were assessed of which 15 (18.1%) were males and 68 (81.9%) females. Body weight and height of individual patients were used in calculating their respective BMI values. The respective %BF values were determined taking into consideration of the age, gender and BMI. Maximum values of BMI (34.71 kg/m2) and %BF (46.37%) were obtained, for which they were females and the minimum values of BMI (12.08 kg/m2) and %BF (12.35%) respectively. The patient with the minimum %BF value was male and that of BMI was female. It was observed from the results that females have higher values of both BMI and %BF than their male counterparts. The study reveals higher rate of female cancer incidence than males.
文摘The scientific studying of kissing is known as Philematology. This originates from the Greek word PHILOS in the ancient days meaning earthly. The study of kissing shows you what kissing means and its place in various cultures. (Lana Citron 2010, a Compendium of Kisses), and the difference between Simple Kiss versus Passionate kiss. In simple kisses only 2 muscles are involved. While in passionate kisses there may be about 23 - 34 facial muscles and 112 postural muscles involved. What you can tell from even the simplest of kisses. From the book I Love You. Now What? During kissing, a lot of chemical reactions take place in the brain and the body as a whole. The part of the brain in which these chemicals are secreted is the pituitary gland, where oxytocin, serotonin and dopamine are secreted. The oxytocin which is also sometimes referred to as the cuddle hormone or the love hormone aids in social bonding. It is produced in the hypothalamus and secreted into the bloodstream by the posterior pituitary gland. Oxytocin is released when the cells are excited. Oxytocin can also be referred to aid carbetocin, manufactured version, Pitocin, alpha-hypophamine and syntocinon. It is a team player in social behaviour and mother-infant bonding. The serotonin which is also known as a “happy hormone” is an important chemical and a neurotransmitter in the human body serves as a hormonal modulator that is serotonin aids regulating an individual kissing pattern, sleeping pattern, aggressive pattern, appetite and digestion pattern, memory and mood pattern and sexual pattern. Finally, the dopamine which is also known as a “happy hormone” is a monoamine neurotransmitter which belongs to the catecholamine family that is made up of epinephrine, norepinephrine and dopamine. This dopamine helps an individual to enjoy the act of kissing.
文摘A lutetium 177 (<sup>177</sup>Lu) radiopharmaceutical has been used as a theragnostic agent in molecular radiotherapies. This study aimed to produce images simulating those obtained in a total body imaging study with hot lesions to assess and investigate the image quality of the Hawkeye SPECT/CT images from Lu-177. The NEMA image quality phantom (PTW) with spheres (inner diameters of 10, 13, 17, 22, 28 and 37 mm) and lung insert was used. The measured volume in the background of the current phantom setting was 9482 mL. The five smaller spheres were filled with an activity concentration of 0.461 MBq/mL and the biggest sphere was filled with water. The phantom was placed on the couch and scanned at four hot sphere-to-background concentrations, which are no background, 16:1, 8:1 and 4:1. The images obtained from the scans were imported onto the OXIRIS image analysis tool. Regions of interest (ROIs) were drawn on each sphere of the reconstructed SPECT image. Image contrast and background variability ratios for hot spheres were used as measures of image quality. In addition, the accuracy of corrections were determined from the uniform background and cold lung insert regions. The 37 mm cold sphere had the highest percent contrast, whiles the 10 mm hot sphere had the least for the various hot sphere to background ratios. The background variability for each hot sphere was also determined. The average lung residual error was calculated to be 23.13% for the 16:1 and 22.57% for both the 8:1 and 4:1 hot sphere to background ratio. The results show that the scanner has very good overall performance.
文摘Thermoplastic immobilizing masks have dosimetric effects on the patient’s skin dose. The thermoplastic percentage depth dose (PDD), equivalent thickness of water for the masks and surface doses were determined. The surface dose factors due to the thermoplastic mask was found to be 1.7949, 1.9456, 2.0563, 2.1967, 2.3827, 2.5459 and 2.6565 for field sizes of 5 × 5, 8 × 8, 10 × 10, 12 × 12, 15 × 15, 18 × 18 and 20 × 20 cm<sup>2</sup> respectively which shifted the percentage depth dose curve to lower values. The physical thermoplastic thickness was measured to be between 2.30 and 1.80 mm, and the equivalent thicknesses of water, d<sub>e</sub>, were determined to be between 1.2 and 1.00 mm. This meant that, as the mask thickness decreased, its water equivalent thickness also decreased. The presence of the mask material increased the skin dose to a factor of 1%. The thermoplastic mask factor was also found to be 0.99.
文摘This study was done to quality assure the Hawkeye SPECT/CT at the St. Olav’s hospital and create a clinical method for doing individual dosimetry with <sup>177</sup>Lu-octreotate in targeted radionuclide therapy for neuroendocrine tumors. Various quality control parameters were performed on Infinia Hawkeye SPECT/CT. A calibration dose of 160% ± 2% MBq was ordered and first calibrated for all the dose calibrators. The uniformity test was obtained using a 40 MBq Tc-99m point source positioned 2.5 m away from the two detectors. A 200 MBq Tc-99m was diluted in 70 ml of water, dispersed in six syringes for the registration test. A Lu-177 point source was placed in front of the detectors, one at a time, to check the energy peaks. The Jaczczak phantom with a hollow sphere set (volumes: 0.5, 1, 2, 4, 8, and 16) ml with an additional 60 ml sphere was used for the 3D sensitivity and recovery with Lu-177. Total activity of 945.3 MBq was added to 160 ml of water yielding an activity concentration of 5.908 MBq/ml in the spheres. The phantom was then scanned at various time intervals. A cylindrical phantom with a volume of 6283 ml was also used to obtain the cross-calibration measurement (cps/MBq). Total activity of 995.6 MBq was added and the phantom was scanned at days 0, 6, 13 and 23. The dose calibration factor was changed from 762 to 760 to achieve correct doses. The 2D mean sensitivity factor was 5.56 cps/MBq. Uniformities for both detectors were approved after iteration calibration of the PM tubes. The X-ray to SPECT registration was found to be accurate and within specifications. The energy peak test revealed off-centered 208 keV energy peaks for the two detectors. Quality assurance of imaging devices using radiation is essential for radiation protection and ensures a high-quality image.
基金2023 Nanjing Medical University Wuxi Medical Center General Projects(Grant No.WMCG202338),China.
文摘Objective:To reveal the effect of boiling time on radionuclide concentrations in seafood by investigating boilingrepresented cooking practices,in order to fill the knowledge gap on how boiling time affects human radiation exposure.-Methods:A total of 13 seafood species of four categories(fish,crustacean,mollusk and algae)were collected from the coastal areas of China and analyzed for radionuclide contents left after boiling at 5,10,20 and^(40)min under 100◦C.Grossαandβ,^(40)K,^(226)Ra,^(232)Th,^(137)Cs were measured using the low backgroundαandβcounter and the gamma-spectrometer.Results:The contents of radionuclides decreased significantly with the increasing boiling time.The average retention rate ofα-emitting radionuclide in in fish,crustacean,mollusk,and algae decreased to 64.47%,53.34%,84.12%and 62.63%after 5 min of boiling,respectively,and then to 15.46%,14.21%,71.94%,and 27.27%after^(40)min,respectively.The average retention rate ofβ-emitting radionuclide in in fish,crustacean,mollusk,and algae decreased to 64.89%,43.43%,66.55%and 63.30%after 5 min,respectively,and then to 47.90%,29.01%,45.96%,and 53.24%after^(40)min.The greatest loss of solubility was observed for^(40)K with the average retention rate of 47.16%after 10 min,and higher retention rate of 87.86%and 90.03%in^(226)Ra and^(232)Th,respectively.Conclusion:Boiling is effective in reducing the radionuclide content,with the committed effective dose(CED)reduction of 44.6%achieved by boiling for 10 min,mainly due to the reduction in^(40)K.A full assessment will also be needed to incorporate more radionuclides(^(210)Po,^(210)Pb,^(228)Ra)into the calculations.
基金This work was supported by the National Key R&D Program of China(2022YFC2503200,2022YFC2503203)the Pre-research project on occupational health standards(20210102)the National Institutes of Health,National Institute on Deafness and Other Communication Disorders,United States(1R01DC015990).
文摘Noise-induced hearing loss(NIHL)has become a global public health problem,and the economic burden of hearing loss caused by noise exposure accounts for 19.6%of the economic burden of all risk factors in the workplace(1).The prevalence of occupational NIHL was estimated to be 10%in relevant occupational population in developed countries and 17%–39%(e.g.,textile and petrochemical industries),and 53%–67%(e.g.,cement and automobile industries)in developing countries in Asia,respectively.(2).In China,occupational noiseinduced deafness has become the second primary occupational disease after pneumoconiosis,with the number of reported cases increasing at an average annual rate of 18.68%from 2010 to 2019(3–4).The prevalence of occupational NIHL in the Chinese occupational population was 21.3%,of which 30.2%was related to high-frequency NIHL(an early sign of NIHL)(2).
基金Zhejiang Province Key Research and Development Project,China(Grant No.2015C03039)Zhejiang Provincial Program for the Cultivation of High-level Innovative Health Talents,China(Grant No.2016-63-07)+2 种基金Health Commission of Zhejiang Province(Grant No.2019KY057)the Program of Occupational Health Risk Assessment of China NIOHP(Grant No.131031109000160004)and the National Institute for Occupational Safety and Health,USA(Grant No.200-2015-M-63857,Grant No.200-2016-M-91922).
文摘Summary What is already known about this topic?Occupational noise-induced hearing loss(NIHL)has been the second most common occupational disease in China.Noise energy is the main risk factor for occupational NIHL.Evidence shows the temporal structure of noise(as indicated by kurtosis metric)contribute to the development of NIHL.However,the role of the kurtosis metric in evaluating the risk of occupational NIHL associated with complex noise has been rarely reported.
