Dose inter-comparison studies for Co γ-ray and 10 MeV electron beam irradiation were carried out 60 from July to October in 2002. The purpose of the studies was to check the reliability of the alanine-PE film dosime-...Dose inter-comparison studies for Co γ-ray and 10 MeV electron beam irradiation were carried out 60 from July to October in 2002. The purpose of the studies was to check the reliability of the alanine-PE film dosime- ters made by CIAE, which will be used as transfer standard dosimetry system mainly for electron beam irradiation. The expanded uncertainty of CIAE alanine/EPR dosimetry system was 4.1% for doses not higher than 10 kGy and 5.4% for those above 10 kGy (k=2). CIAE alanine-PE film dosimeters were sent to JAERI, RISO (National Labora- tory in Denmark) and INCT respectively, which were irradiated by Co gamma-rays or electron beams in each labo- 60 ratory. The irradiated dosimeters were then sent back to CIAE for electron paramagnetic resonance (EPR) analysis. The agreements were obtained to be ±1.9% for gamma-ray dose measurement and ±4.3% for electron beam dose measurement, which were all within the combined uncertainty of the reference and CIAE alanine/EPR dosimetry system. Furthermore, the overall mean ratio was found to be 0.995 with 1.8% in the coefficient of variation (CV). The preliminary inter-comparison studies indicated that CIAE film alanine/EPR dosimetry system had the potential to be used as a transfer dosimetry system for high dose measurement.展开更多
Background: After the failure of medical treatment, the surgery of chronic rhinosinusitis (CRS) is planned according to endoscopic and paranasal sinus computed tomography (CT) findings. Objective: The aim of this pros...Background: After the failure of medical treatment, the surgery of chronic rhinosinusitis (CRS) is planned according to endoscopic and paranasal sinus computed tomography (CT) findings. Objective: The aim of this prospective study was to evaluate whether this study method might be eligible in studies aiming at radiation dose reduction. Sinus CT scans were chosen as a model because of the high variation of the radiological anatomy of surgically important sinonasal structures. We hypothesized that 3 mm-slice-thick reconstruction CT had poor reproducibility. Methods: 59 CRS patients underwent routine multi-detector sinus CT (CT<sub>MD</sub>). CT<sub>3mm</sub> was reconstructed from CT<sub>MD</sub> data-sets. Lund-Mackay (LM) scores and 43 other structural parameters were analyzed blinded. Agreement was studied between CT<sub>MD</sub> and CT<sub>3mm</sub> (intra-observer reproducibility), and between three observers (inter-observer reproducibility) by using Cohen’s kappa. Results: The inter-observer agreement was moderate (kappa 0.4 - 0.6, p < 0.01) in the majority of structures of CT<sub>3mm</sub> scans. The intra-observer reproducibility of CT<sub>3mm</sub> scans was very good in most structures, however, it was poor in important structures such as frontal and spheno-ethmoid recess, lamina papyracae, and location of optic nerve or anterior ethmoidal artery. The grade of surgeon’s confidence of CT<sub>3mm</sub> in comparison to CT<sub>MD</sub> was lower (kappa 0.2 - 0.4, P < 0.05). Conclusion: This methodology might have some use in studies aiming at radiation dose reduction. As was expected, 3 mm-slice-thick reconstruction CT had poor reproducibility and surgeon’s confidence. More recent methods such as cone beam computed tomography scans have nowadays more relevant dose reduction potential.展开更多
As public health policies shifted in 2023 from emergency response to long-term COVID-19 disease management,immunization programs started to face the challenge of formulating routine booster campaigns in a still highly...As public health policies shifted in 2023 from emergency response to long-term COVID-19 disease management,immunization programs started to face the challenge of formulating routine booster campaigns in a still highly uncertain seasonal behavior of the COVID-19 epidemic.Mathematical models assessing past booster campaigns and integrating knowledge on waning of immunity can help better inform current and future vaccination programs.Focusing on the first booster campaign in the 2021/2022 winter in France,we used a multi-strain age-stratified transmission model to assess the effectiveness of the observed booster vaccination in controlling the succession of Delta,Omicron BA.1 and BA.2 waves.We explored counterfactual scenarios altering the eligibility criteria and inter-dose delay.Our study showed that the success of the immunization program in curtailing the Omicron BA.1 and BA.2 waves was largely dependent on the inclusion of adults among the eligible groups,and was highly sensitive to the inter-dose delay,which was changed over time.Shortening or prolonging this delay,even by only one month,would have required substantial social distancing interventions to curtail the hospitalization peak.Also,the time window for adjusting the delay was very short.Our findings highlight the importance of readiness and adaptation in the formulation of routine booster campaign in the current level of epidemiological uncertainty.展开更多
Radiation-induced inter-device leakage is studied using an analytical model and TCAD simulation. There were some different opinions in understanding the process of defect build-up in trench oxide and parasitic leakage...Radiation-induced inter-device leakage is studied using an analytical model and TCAD simulation. There were some different opinions in understanding the process of defect build-up in trench oxide and parasitic leakage path turning on from earlier studies.To reanalyze this problem and make it beyond argument,every possible variable is considered using theoretical analysis,not just the change of electric field or oxide thickness independently. Among all possible inter-device leakage paths,parasitic structures with N-well as both drain and source are comparatively more sensitive to the total dose effect when a voltage discrepancy exists between the drain and source region.Since N-well regions are commonly connected to the same power supply,these kinds of structures will not be a problem in a real CMOS integrated circuit.Generally speaking,conduction paths of inter-device leakage existing in a real integrated circuit and under real electrical circumstances are not very sensitive to the total ionizing dose effect.展开更多
文摘Dose inter-comparison studies for Co γ-ray and 10 MeV electron beam irradiation were carried out 60 from July to October in 2002. The purpose of the studies was to check the reliability of the alanine-PE film dosime- ters made by CIAE, which will be used as transfer standard dosimetry system mainly for electron beam irradiation. The expanded uncertainty of CIAE alanine/EPR dosimetry system was 4.1% for doses not higher than 10 kGy and 5.4% for those above 10 kGy (k=2). CIAE alanine-PE film dosimeters were sent to JAERI, RISO (National Labora- tory in Denmark) and INCT respectively, which were irradiated by Co gamma-rays or electron beams in each labo- 60 ratory. The irradiated dosimeters were then sent back to CIAE for electron paramagnetic resonance (EPR) analysis. The agreements were obtained to be ±1.9% for gamma-ray dose measurement and ±4.3% for electron beam dose measurement, which were all within the combined uncertainty of the reference and CIAE alanine/EPR dosimetry system. Furthermore, the overall mean ratio was found to be 0.995 with 1.8% in the coefficient of variation (CV). The preliminary inter-comparison studies indicated that CIAE film alanine/EPR dosimetry system had the potential to be used as a transfer dosimetry system for high dose measurement.
文摘Background: After the failure of medical treatment, the surgery of chronic rhinosinusitis (CRS) is planned according to endoscopic and paranasal sinus computed tomography (CT) findings. Objective: The aim of this prospective study was to evaluate whether this study method might be eligible in studies aiming at radiation dose reduction. Sinus CT scans were chosen as a model because of the high variation of the radiological anatomy of surgically important sinonasal structures. We hypothesized that 3 mm-slice-thick reconstruction CT had poor reproducibility. Methods: 59 CRS patients underwent routine multi-detector sinus CT (CT<sub>MD</sub>). CT<sub>3mm</sub> was reconstructed from CT<sub>MD</sub> data-sets. Lund-Mackay (LM) scores and 43 other structural parameters were analyzed blinded. Agreement was studied between CT<sub>MD</sub> and CT<sub>3mm</sub> (intra-observer reproducibility), and between three observers (inter-observer reproducibility) by using Cohen’s kappa. Results: The inter-observer agreement was moderate (kappa 0.4 - 0.6, p < 0.01) in the majority of structures of CT<sub>3mm</sub> scans. The intra-observer reproducibility of CT<sub>3mm</sub> scans was very good in most structures, however, it was poor in important structures such as frontal and spheno-ethmoid recess, lamina papyracae, and location of optic nerve or anterior ethmoidal artery. The grade of surgeon’s confidence of CT<sub>3mm</sub> in comparison to CT<sub>MD</sub> was lower (kappa 0.2 - 0.4, P < 0.05). Conclusion: This methodology might have some use in studies aiming at radiation dose reduction. As was expected, 3 mm-slice-thick reconstruction CT had poor reproducibility and surgeon’s confidence. More recent methods such as cone beam computed tomography scans have nowadays more relevant dose reduction potential.
基金funded by:Agence Nationale de la Recherche project DATAREDUX(ANR-19-CE46-0008-03)to VCANRSeMaladies InfectieusesEmergentes project EMERGEN(ANRS0151)to VC+2 种基金Horizon Europe grant ESCAPE(101095619)to VCEU HORIZON grant VERDI(101045989)EU Horizon 2020 grant MOOD(H2020-874850)to VC.The study is catalogued as MOOD105。
文摘As public health policies shifted in 2023 from emergency response to long-term COVID-19 disease management,immunization programs started to face the challenge of formulating routine booster campaigns in a still highly uncertain seasonal behavior of the COVID-19 epidemic.Mathematical models assessing past booster campaigns and integrating knowledge on waning of immunity can help better inform current and future vaccination programs.Focusing on the first booster campaign in the 2021/2022 winter in France,we used a multi-strain age-stratified transmission model to assess the effectiveness of the observed booster vaccination in controlling the succession of Delta,Omicron BA.1 and BA.2 waves.We explored counterfactual scenarios altering the eligibility criteria and inter-dose delay.Our study showed that the success of the immunization program in curtailing the Omicron BA.1 and BA.2 waves was largely dependent on the inclusion of adults among the eligible groups,and was highly sensitive to the inter-dose delay,which was changed over time.Shortening or prolonging this delay,even by only one month,would have required substantial social distancing interventions to curtail the hospitalization peak.Also,the time window for adjusting the delay was very short.Our findings highlight the importance of readiness and adaptation in the formulation of routine booster campaign in the current level of epidemiological uncertainty.
文摘Radiation-induced inter-device leakage is studied using an analytical model and TCAD simulation. There were some different opinions in understanding the process of defect build-up in trench oxide and parasitic leakage path turning on from earlier studies.To reanalyze this problem and make it beyond argument,every possible variable is considered using theoretical analysis,not just the change of electric field or oxide thickness independently. Among all possible inter-device leakage paths,parasitic structures with N-well as both drain and source are comparatively more sensitive to the total dose effect when a voltage discrepancy exists between the drain and source region.Since N-well regions are commonly connected to the same power supply,these kinds of structures will not be a problem in a real CMOS integrated circuit.Generally speaking,conduction paths of inter-device leakage existing in a real integrated circuit and under real electrical circumstances are not very sensitive to the total ionizing dose effect.
