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Objective To preliminarily compare 6LiF-7LiF and CR39 in individual neutron dose monitoring, and to provide a reference for improving individual neutron dose monitoring. Methods According to the GBZ 128-2019, 26 radiation workers from 7 institutions received individual neutron dose monitoring with 6LiF-7LiF and CR39 at the same time. The monitoring results were analyzed. Results For most of the workers, the personal neutron dose equivalent Hp(10) was less than the minimum detectable level. The results with the two monitoring methods differed in 6 of 26 workers. Conclusion Both 6LiF-7LiF and CR39 monitoring methods can be used for individual neutron dose monitoring for radiation workers, but the difference between 6LiF-7LiF and CR39 (in threshold energy, energy response, etc.) should be considered so that different types of radiation workers receive appropriate individual neutron dose monitoring.
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Objective To establish a method to characterize the size and density of the female breast based on three-dimensional images of breast cone-beam computed tomography (CBCT), and describe the breast characteristics of women in a region of China, and to explore its value in dosimetric assessment for breast CBCT examinees. Methods We retrospectively surveyed the breast CBCT images of 203 women in a grade A tertiary hospital in a southwestern city of China from January 2021 to March 2023. The effective diameter of the breast at the chest-wall (Deff), chest wall-to-nipple length (CNL), the effective diameter of the breast at half of CNL (Dh/2), breast volume (BV), glandular volume (GV), and volumetric breast density (VBD) were measured using the specific tools of the Koning Imaging Viewer system. The differences between groups were assessed using the Kruskal-Wallis H test. The correlation between variables was assessed using the Spearman’s correlation coefficient. Results The median values of Deff, Dh/2, CNL, BV, GV, and VBD of the surveyed population were 11.9 cm, 8.3 cm, 6.5 cm, 327.7 cm3, 47.0 cm3, and 15.4%, respectively. GV and VBD had significant negative correlations with age. Deff, Dh/2, CNL, and BV were significantly negatively correlated with VBD. Conclusion We established a quantitative method to analyze female breast characteristics based on three-dimensional breast CBCT images, and preliminarily characterized the female breast in a region of China, which can provide methodological support for the investigation of female breast characteristics in various regions of China in the future.
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With the extensive use of neutron sources in industry, medicine, and scientific research, the number of people exposed to neutron has been increasing, which highlights the importance of personal neutron dose monitoring in the field of radiation protection. In the past decades, researchers have developed and improved a variety of techniques and methods for personal neutron dose monitoring. This paper focuses on the problems and research progress of track dosimeters (solid-state nuclear track dosimeters and fluorescent nuclear track dosimeters), luminescent dosimeters (thermoluminescent dosimeters and optically stimulated luminescent dosimeters), and bubble dosimeters in personal neutron dose monitoring.
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ObjectiveTo explore the formulation rules for the treatment of heart pain in the Medical Heart Enlightenment （《医学心悟》） from the perspective of the "Tangye Jingfa Tu"， thereby providing a way of thinking about the treatment of heart pain in traditional Chinese medicine （TCM） and the study of the Medical Heart Enlightenment. MethodThe "Tangye Jingfa Tu" contained in the Secrets for Auxiliary Cultivation Life： The Essential Method of Using Herbal Medicine for the Differential Treatment of the Five Zang Organs （《辅行诀五脏用药法要》） was used to analyze the nine prescriptions for heart pain in Volume Ⅲ of the Medical Heart Enlightenment by CHENG Guopeng in the Qing dynasty. A "table for analyzing the formulation of the nine prescriptions for heart pain" was developed. The analysis diagrams for decoction and meridian rules in nine prescriptions for heart pain were plotted and the compatible structure of the medicinal flavors was analyzed. ResultThe composition of Chenxiang Jiangqisan for the treatment of Qi-induced heart pain is "five pungent， four bitter， and two sweet drugs"， the composition of Shouniansan for the treatment of blood-induced heart pain is "five bitter， four pungent， three sweet， and one salty drugs"， the composition of Qingzhongtang for the treatment of heat-induced heart pain is "six bitter， three pungent， and two sweet drugs”， the composition of Jiangfutang with Cinnamomi Cortex for cold-induced heart pain is "three pungent and two sweet drugs"， the composition of Xiaobanxia modified with Fuling Tang for treating fluid retention-induced heart pain is "two pungent and two sweet drugs"， the composition of Baohetang for treating heart pain due to dietary stagnation is "five sweet， four pungent， four bitter， and one sour drugs"， the composition of Guipitang for the treatment of deficiency-induced heart pain is "eight sweet， four bitter， three pungent， and one sour drugs"， the combination of Huachongwan for the treatment of worm-induced heart pain is "seven bitter， six pungent， and four sweet drugs"， the composition of Shenzhusan， Congbaijiu， and Shengjiangtang for the treatment of resistance-induced heart pain is "eight pungent， four bitter， and two sweet drugs". ConclusionFrom the perspective of the "Tangye Jingfa Tu"， the Medical Heart Enlightenment is based on the compatibility principle of "pungent-bitter-sweet drugs" in the treatment of heart pain， with heart deficiency treated with salty drugs for tonifying， or bitter-sweet-salty drugs， and heart excess treated with bitter drugs for purging， or sweet-pungent-bitter drugs， mostly applying the transformation rules of five medicinal flavors， i.e.， "sweet-pungent-bitter drugs" and promoting the action of the pungent and sweet drugs acting on the spleen into the heart to relieve and purge the heart. In most cases， the treatment focuses on harmonizing the heart， liver， spleen， and kidneys， with an emphasis on the mother-child relationship and the application of the principles of the five elements generating and controlling each other. If the progression of the disease involves both the mother and child organs， the formulation should adhere to the compatibility rule of "the child organ makes the mother organ excess and the mother organ makes the child organ deficient".
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Wumeiwan are recorded in the Jueyin chapter of Treatise on Cold Damage and Miscellaneous Diseases （《伤寒杂病论》）， and many doctors in the past dynasties believed that they had the effects of calming intestinal ascarid by warming Zang organs. The clinical application was limited. Since KE Qin， a doctor in the Qing dynasty， proposed that Wumeiwan were the primary prescription against Jueyin diseases， Wumeiwan have been valued by doctors， and their clinical application has also been expanded. The syndrome indicated for Wumeiwan is attributed， not only to the ascarid internal harassment， but to the abnormal Qi movement of wind and wood in Jueyin and the dysfunction of Yin and Yang. According to the functions of six meridians based on the theory of "open-close axis" in Huangdi's Internal Classic （《黄帝内经》） and the original texts of Treatise on Cold Damage and Miscellaneous Diseases， Yinshu refers to Jueyin. Wumeiwan， the primary prescription against Jueyin diseases， have the function of connecting Yin and Yang， and they can treat diseases caused by Qi disturbance of Jueyin and cold and heat in complexity. Sharing the same resource， the Secrets for Auxiliary Cultivation Life： The Essential Method of Using Herbal Medicine for the Differential Treatment of the Five Zang Organs （《辅行诀五脏用药法要》） and Treatise on Cold Damage and Miscellaneous Diseases both consult Models of the Classic of Decoction （《汤液经方》）. The formulation rules of tonic/purgative and collapse-saving prescriptions in Secrets for Auxiliary Cultivation Life follow the recorded "Tang Ye Jing Fa Tu" （an image revealing the compatibility principles of Chinese herbal drugs） and are closely related to the five elements theory. By exploring the formulation rules in "Tang Ye Jing Fa Tu" and the five elements of drugs， this study analyzed Wumeiwan and proved that Wumeiwan mainly acted on the liver， spleen， and heart. According to the Five Zang-organs Storing Spirit theory from Huangdi's Internal Classic， the above three organs are closely related to emotional adjustment. Therefore， the treatment of emotional disorders caused by qi disturbance of Jueyin and cold and heat in complexity with Wumeiwan is supported by evidence. At the end of this article， the reports on the treatment of emotional disorders with Wumeiwan in recent years were listed and reviewed. This article provides new ideas for the clinical application of Wumeiwan in the treatment of emotional disorders and expands the application range.
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Mammography has played an essential role in the screening and treatment of breast cancer. However, the application of X-rays will also increase the risks of breast cancer while improving its detection rate. Moreover, the risks will increase with an increase in the radiation dose. Since the glandular tissue in breasts is sensitive to radiation, the evaluation of the average glandular dose (AGD) in mammography has attracted considerable international attention. Compared to relatively mature dosimetric studies on traditional two-dimension mammography and digital breast tomosynthesis, the method for the dose evaluation of the new cone beam CT for breasts are still subjected to research. This paper reviews and explores the current status of studies on the assessment method and relevant influencing factors of AGD under different types of mammography equipment.
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Objective@#To improve radiation testing institutions’ ability and levels of personal dose monitoring for external exposure and standardize monitoring work.@*Methods@#According to Testing Criteria of Personnel Dosimetry Performance for External Exposure (GBZ 207—2016), the intercomparison programme was made, the 2021 class-based personal dose monitoring intercomparison were organized by the National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention and provincial monitoring institutions.@*Results@#A total of 150 institutions participated in the 2021 national intercomparison of personal dose monitoring capability. Of them, 143 (95.3%) passed the assessment, including 51 excellent institutions (excellent rate, 34.0%), and 7 (4.7%) failed to pass the assessments.@*Conclusion@#The 2021 national personal dosimetry performance intercomparison showed great improvements in the pass rate and excellent rate compared with previous national assessments. However, still seven institutions failed to pass this assessment, including four institu- tions with class A qualifications. The testing institutions need to find out the reasons to increase their testing ability. This class-based intercomparison improved the point-to-plane relationship between the organizing and testing institutions, help- ing the organizing institution focus on improving the testing ability of provincial testing institutions and class A radiation health service institutions.
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Objective In order to improve the personal dose monitoring ability of radiation health technical institutions, and standardize the detection methods and procedures. Methods Develop adetailed assessment plan according to GBZ 207—2016 “Testing criteria of personnel dosimetry performance for external exposure”, organize a national assessment of personal dose monitoring capabilities in 2020, analyze the problems arising from the assessment, and strengthen supervision and training in the future. Results A total of 457 institutions participated in this assessment, of which 421 were qualified (including 74 excellent institutions, with an excellent rate of 16.2%), and 36 were unqualified, accounting for 92.1% and 7.9% respectively. Conclusion The number of institutions that participated in the assessment this year reaches a record high, with a passing rate 4.08% higher than that in 2019. The overall monitoring capacity of the country has been greatly improved. However, some institutions still have problems such as irregular symbol writing, unupdated detection standards, and large deviations in testing data. It is necessary to improve the ability of loboratory detection and data analysis, standardize the operation process, and ensure the quality of assessment.
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Objective@#To compare the test results of domestic and imported eye lens and ring dosimeters, and master some dosimetric performance indexes of eye lens and ring dosimeters.@*Methods@#According to IEC 62387—2012 and GBZ 128—2019, the performance of the eye lens dosimeters and ring dosimeters with the domestic thermoluminescence detectors were compared with the imported thermoluminescence detectors in photon response. The dose response deviation of the im- ported eye lens dosimeter and imported ring dosimeter was studied under the same irradiation condition. The difference of linear response between imported ring dosimeter and domestic ring dosimeter was studied under the same irradiation condition. @*Results@#The same dose was irradiated to domestic and imported thermoluminescence detectors in the imported eye lens and imported ring dosimeters, and the linear correlation coefficient all met R2 > 0.999. The maximum response devi- ation of the imported eye lens dosimeter and ring dosimeter was less than 10.0% for the same dose. Two kinds of imported ring dosimeters and one kind of domestic ring dosimeter were irradiated with the same dose, and the linear correlation coefficient all met R2 > 0.99.@*Conclusion@#Both domestic detectors and imported detectors can meet the needs of monitoring re- quirements. There was no obvious difference in linear response between imported ring dosimeter and domestic ring dosimet- er. The repeatability of imported eye lens dosimeter and imported ring dosimeter met the performance requirements of the dosimeter.
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Objective:To enhance the capabilities of individual monitoring technology services for external exposure.Methods:The intercomparison results of the national individual monitoring for external exposure during 2015-2019 were presented, together with a summary and analysis provided of the main existing problems.Results:By 2019, 382 of individual monitoring technology service uints, from 30 provinces, autonomous regions or municipalities, participated in the individual monitoring intercomparisons results, involving disease control and prevention centers, occupational prevention and control institutions, research institutes, universities, nuclear industry, medical institutions, and companies. Except for slightly low in 2017, the pass rate in the other four years was above 90%. The excellence rate increased with the years.Conclusions:The capabilities of individual monitoring service units can meet the concerned requirements and provide standardized monitoring report for the period of 2015 to 2019, but with some being unqualified. These service units should carefully analyze and identify the reasons for the failure, standardize the quality control of laboratory, and improve the level of measurement and the ability of data analysis.
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Objective To describe the evaluation method of uncertainty in measurement of depth individual dose equivalent.Methods Based on the performance of the personal dosimeter,GUM method was used to evaluate the uncertainty of Hp(10) measurement by using a personal dosimeter.Results The relative extended uncertainty was 28％ when the measurement result was corrected by nonlinear response and energy response,as well as 33％ when not corrected in the same way.Conclusions This method can be used to effectively evaluate the uncertainty arising from personal dose equivalent Hp(10) measurement in routine monitoring.
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Objective To compare,through experimental measurements,the differences between four kinds of single and double dosimetry algorithms recommend by ICRP 139 Publication in estimating interventional radiology staff's effective dose,with aim to realize the applicability of algorithms for cardiovascular interventional diagnosis and treatment in China.Methods Measurements of organ doses were carried out with an anthropomorphic phantom equipped with thermoluminecent dosimetry and dressed with lead apron and lead collar.The effective doses were calculated using the tissue weighting factors.Meanwhile,the staff's effective doses were also obtained by the use of four kinds of single and double dosimetry algorithms.The later four effective doses were compared with those obtained with phantom methode.Results The effective doses were 0.581 mSv for phantom method,0.667 mSv for Swiss ordinance's algorithm,0.484 mSv for McEwan's algorithm,0.485 mSv for von Boetticher's algorithm and 0.726 mSv for Martin-Magee's algorithm,in ICRP 139 report respectively.The relative deviations to the results of experimental measurement were 14.8％ for Swiss ordinance's algorithm,-16.7％ for McEwan's algorithm,-16.5％ for von Boetticher's algorithm and 24.9％ for Martin-Magee's algorithm,respectively.Conclusions There are great differences between the effective doses of the first operator obtained by four dosimetry algorithms and the simulated result.From the point of view of radiation protection,it is recommended to use the Swiss ordinance's algorithm to carry out individual monitoring of the first operator in the cardiovascular interventional procedures.
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Objective To standardize the uncertainty assessment work of nationwide radiological technical service institutions in respect to individual dose monitoring, to enhance the relevant capability and to ensure the quality of assessment. Methods The 2017 nationwide individual dose monitoring assessment for external exposure was carried out, and the problems found in uncertainty assessment in the submitted reports were analyzed and summarized. Results A total of 259 personal dose monitoring technical service institutions submitted their completed assessment reports and verification/calibration certificates. The accuracy rate of Class A uncertainty evaluation was 20.8％ and that of class B 55.2％ for calibration, 50.6％ for energy response, 25.5％ for angle ring and 51.4％ non-linearity response, respectively. The accuracy rate of effective digits of the estimated values and their uncertainty was 30.4％. Conclusions The ability of these individual dose monitoring institutions to assess uncertainties remains to be improved. It is recommended to enhance systematic training of the institutions with respect to uncertainty evaluation and to standardize the assessment reports, so as to improve the accuracy of the monitoring result and the quality of accuracy reporting.
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Objective To normalize the individual dose monitoring for nationwide radiological workers and to improve individual dose monitoring ability of radiological health monitoring service institutions. Methods The 2017 annual intercomparison was carried out of nationwide external radiation individual dose monitoring result, with summary and analysis completed. Results A total of 283 monitoring service institutions were involved in the 2017 annual intercomparison. Of them, 249 were qualified, 45 excellent and 34 unqualified. The excellent rate was 15.9％ and the pass rate 88.0％. Conclusions Most of individual dose institutions could meet better the requirements by the intercomparison, but some deviated from the references to some degree. It is necessary to strengthen the laboratory operation and standardize data processing and to improve the accuracy end precision of measurement result .
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To present an overview of the indicators of effective dose equivalent assessment in interventional radiology and dosimetry algorithms,together with some problems attracting controversy so far.By literature consultation at home and abroad,some discussions were made on dosimetry algorithms in interventional radiology worldwide,main factors affecting accuracy of the method and the discussions on the optimal position of dosimeter.Suggestions are made on the basis of the recent research result and present dosimeters wearing conditions for reference.
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Objective To understand the dosimetric performance of energy differential type dosimeter.Methods A differential type dosimeter (CTLD-J4000) was chosed to conduct a series of dosimetric performance tests,including linear standard curves,relative response to mean photon radiation energy and incidence angle.Results The linear correlation of CTLD-J4000 energy differential dosimeter was good,with the average photon radiation energy response deviation within ± 20％ and the maximum incidence angle response deviation of 10％.The energy identification could be achieved according to the energy reference value provided by the manufacturer to a certain extent.Conclusions Further experiments are needed to find out the factors influencing measurement result from different dose values and incidence angles.
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Objective To use thermoluminescense dosimeters (TLDs) to evaluate the radiation doses to various critical organs in the computerized imaging reference systems (CIRS) 5 years old pediatric anthropomorphic phantom result ing from Varian kilovohage cone beam CT (kV-CBCT) system based on the standard scanning protocols.Effective dose were also calculated based on dose measurement.Methods A batch of TLDs with consistency no larger than 2％ were selected and annealed.First,the doses in an anthropomorphic pelvic phantom were measured using a CT chamber and TLDs,respectively,based on the standard pelvic protocols.The ratio of the both measurements is the TLD conversion coefficient.Other TLDs from the same batch were placed between two tissue-equivalent inserts and placed into the pre-drilled organ cavities of the pediatric phantom.By using standard protocols,the organs dose were measured,based on which the corresponding effective doses were calculated.Results The TLD conversion coefficient was 3.91 mGy/per reading.By using the standard head,low-dose thorax,pelvis protocol,the whole body effective dose was 0.63,6.85 and 19.3 mSv,respectively.Conclusions It is feasible for using the CT chamber-calibrated TLDs to measure the radiation doses from kV-CBCT to pediatric anthropomorphic phantom.The effective dose in pelvic protocol was higher than in thorax and head protocol,indicating that the pelvic protocol has a penitential to lead to larger radiation damage and higher risk of secondary cancer.
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Objective To establish a new method to analyze the position accuracy of multileaf collimator (MLC) in the dynamic mode.Methods The MLC test sequence was created in a field,where intentional leaf positional errors ranging from 0.1 to 1 mm per centimeter were introduced.In order to establish the relationship between the ion chamber readings and leaf position,whose slope indicated the leaf position error per centimeter,a two-dimensional ion chamber array was used to measure absorbed dose while leaves were moving at dose rates of 100,300 and 600 MU/min,respectively.For routine test,leaf position error was easily found via dose profile in y direction of the field created by dynamic leaves,where the position error could be quantitatively calculated as the slope of absorbed dose line of x direction of the same field.Results The error of 0.2 mm or more per centimeter was obviously shown through y dose profile.The calibration curve was linear at different dose rates.At 600 MU/min,a 0.1 mm leaf position error corresponded to a slope variation of 0.74％,and the differences between the tested errors and the introduced errors were within 0.1 mm.Conclusions The simple and reliable method is helpful to establish the intensity modulated radiation therapy (IMRT) quality control (QC) system.
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Objective To develop the methods for using 0.015 cc pinpoint chambers, 0.007 cc miniature chambers and diode detector to measure Multi-leaf collimator (MLC) small field in IMRT.Methods MAX4000 and Unidos electrometers were connected with different types of small chambers and diode detectors.MLC shaped fields of10 cm×10 cm, 6 cm×6 cm, 4 cm×4 cm, 3 cm×3 cm, 2 cm× 2 cm were defined at 100 cm SSD.The field sizes for the Varian accelerator were defined by the tertiary MLC, while the secondary jaws were kept at 10 cm × 10 cm field, with the monitor units of 250 MU.Each field was measured three times to obtain the average value.The readings of all small fields were normalized to 10 cm × 10 cm field values for comparison of measured and published output factors.Results The relative deviations of the MLC small field output factors from the published outputs are 1.0％ , 1.7％ , 1.5％ and 2.4％, respectively, for Unidos electrometer connected with 0.015 cc pinpoint chamber;0.2％, 0.8％, 0.8％ and 1.4％, respectively, for Unidos electrometer connected with 0.007 cc miniature chamber;and 0.1％, 0.5％, 0.5％ and 0.9％, respectively, for MAX4000 electrometer connected with 0.007 cc miniature chamber.Conclusions The 0.015 cc chamber-measured MLC output factors for 3 cm × 3 cm and 2 cm × 2 cm fields are excellent.As required by IAEA, the relative deviations of the measured output factor from the published output factor are within ± 2％ for 2 cm × 2 cm fields and ± 3％ for larger fields.The results measured using 0.007 cc chamber are better than those measured using 0.015 cc chamber.The measured results using the diode detector, normalized to the 10 cm × 10 cm field, are consistent with the minimum requirements and excellent when being normalized to the 4 cm × 4 cm field.For dosimetric consideration, MLC small field output factor should be measured using small chamber and diode detector.The method is accurate and reliable, therefore, all measured output factors for MLC small fields should be input into radiation treatment plan system.