Adenoid cystic carcinoma of the peripheral lung: a case report

Adenoid cystic carcinoma of the peripheral lung is a rare entity. We recently encountered a patient with adenoid cystic carcinoma. A 75-year-old woman showed a nodular lesion with 10 mm in diameter in the right upper lung field on chest radiography. The diagnosis was unclear, but lung cancer could not be ruled out. Thoracoscopic biopsy was performed, and intraoperative pathological diagnosis revealed the carcinoma of the lung. We enforced upper lobectomy and mediastinal lymph node dissection to the patient. Histopathological examination revealed adenoid cystic carcinoma with a characteristic cribriform structure. Immunohistochemical examination revealed that the tumor cells were positive for thyroid transcription factor 1 (TTF-1), this tumor was diagnosed primary ACC of the lung

Transmutation Strategy Using Thorium-Reprocessed Fuel ADS for Future Reactors in Vietnam

Nuclear power is believed to be a key to the energy security for a developing country like Vietnam where the power demanding increases rapidly every year. Nevertheless, spent nuclear fuel from nuclear power plants is the source of radiotoxic and proliferation risk. A conceptual design of ADS utilizing thorium fuel as a based fuel and reprocessed fuel as a seed for nuclear waste transmutation and energy production is proposed as one of the clean, safe, and economical solutions for the problem. In the design, 96 seed assemblies and 84 blanket assemblies were inserted into the core to make a heterogeneous subcritical core configuration. Introducing thorium fuel into the core offers an effective way to transmute plutonium and minor actinide (MA) and gain energy from this process. Transmutation rate as a function of burnup is estimated using MCNPX 2.7.0 code. Results show that by using the seed-blanket designed ADS, at 40 GWd/t burnup, 192 kg of plutonium and 156 kg of MA can be eliminated. Equivalently, 1  ADS can be able to transmute the transuranic (TRU) waste from 2  LWRs. 14 units of ADS would be required to eliminate TRUs from the future reactors to be constructed in Vietnam

Impact of Thorium Capture Cross Section Uncertainty on the Thorium Utilized ADS Reactivity Calculation

Recently, the researches on fast neutron spectrum system utilized thorium fuel are widely conducted. However, the recent thorium cross section libraries are limited compared to uranium cross section libraries. The impact of thorium cross section uncertainty on thorium fuel utilized accelerator driven system (ADS) reactivity calculation is estimated in this study. The uncertainty of the keff caused by 232Th capture cross section of JENDL-4.0 is about 1.3%. The uncertainty of JENDL-4.0 is needed to be enhanced to provide more reliable results on reactivity calculation for the fast system. The impact of uncertainty of  232Th capture cross section of ENDF/B-VII is small (0.1%). Therefore, it will cause no significant impact of the thorium cross section library on the thorium utilized ADS design calculation

Bayesian Inference Based on Monte Carlo Technique for Multiplier of Performance Shaping Factor

Takeda S., Kitada T.. Bayesian Inference Based on Monte Carlo Technique for Multiplier of Performance Shaping Factor. ASCE-ASME Journal of Risk and Uncertainty in Engineering Systems, Part B: Mechanical Engineering 10, 041203 (2024); https://doi.org/10.1115/1.4065531.The human error probabilities (HEP) can be estimated using multipliers that correspond to the level of performance shaping factors (PSFs) in the human reliability analysis (HRA). This paper focuses on the adjustment of multipliers through Bayesian inference based on Monte Carlo techniques using the experimental results from simulators. Markov Chain Monte Carlo (MCMC) and Bayesian Monte Carlo (BMC) are used as Bayesian inference methods based on Monte Carlo techniques. MCMC is utilized to obtain the posterior distribution of the multipliers. BMC is used for the estimation of the moments of the posterior distribution such as the mean and variance. The results obtained by MCMC and that by BMC well agree with the reference results. As a case study, the data assimilation was performed using the results of the simulator experiment of Halden reactor. The results show that the multiplier changes by the result of a particular scenario and HEP of another scenario that uses the same multiplier also changes by data assimilation. Also, in the case study, the correlation between multipliers is obtained by the data assimilation and the correlation contributes to the reduction of uncertainty of HEP

Fundamental design activity of fast reactor with inherent safety characteristics for effective transmutation of minor actinide

In order to reduce Minor Actinides (MA), the transmutation of MA in a fast reactor has been studied in Japan. In the transmutation in the fast reactor, MAs are mixed in the ordinary MOX fuel and they are burned up. For the design of a fast reactor with inherent safety characteristics, it is necessary to secure negative void reactivity and cooling via a natural convection under the situation of the severe accident. Therefore, this study aims to fundamentally design the fast reactor for the MA transmutation with inherent safety characteristics. First, in order to clarify the design range of the core design parameter, the parametric study was conducted using four design parameters determining the core configuration. As the result of this parametric study, the feasible combination of each four parameters satisfying the negative void reactivity was clarified. Among parameters satisfying the negative void reactivity, the condition that results in the maximum reduction of MA amount was obtained. Secondly, the CFD simulation focused on the sodium coolant channel between fuel pins was conducted. In this CFD simulation, as the first step for the design activity, the confirmation of the occurrence condition of a natural convection due to the decay heat after shifting to the transient situation was confirmed. Temperature and velocity distribution were evaluated. And the heat transfer efficiency was summarized using Ra number and Nu number

Study on the Impact of Thermal Agitation on Doppler Coefficient in Epithermal Range for Gd-Bearing Fuel

The impact of thermal agitation on Doppler coefficient for Gd-bearing fuel was analyzed. It was found through the analysis that the impact increases when a small amount of Gd2O3 is added to pure UO2 fuel although the impact decreases for a large amount of Gd2O3. This tendency was discussed with the usage of simplified expression for the difference of Doppler coefficient. The simplified expression was used to consider the tendency, and it was revealed that the tendency mainly comes from the rapid decrement of multiplication factor and the relatively slow decrement of the magnitude of sensitivity coefficient of U-238 capture cross section at low Gd2O3 concentration. Similar tendency which shows a maximum impact on Doppler coefficient at interior concentration is expected for other UO2 fuel with a slight content of strong absorber. This indicates that Doppler coefficient of UO2 fuel system with low content of strong absorber should be analyzed carefully by considering thermal agitation in epithermal range

Distinct sensitivities of the lateral prefrontal cortex and extrastriate body area to contingency between executed and observed actions

Detecting relationships between our own actions and the subsequent actions of others is critical for our social behavior. Self-actions differ from those of others in terms of action kinematics, body identity, and feedback timing. Thus, the detection of social contingency between self-actions and those of others requires comparison and integration of these three dimensions. Neuroimaging studies have highlighted the role of the frontotemporal network in action representation, but the role of each node and their relationships are still controversial. Here, we conducted a functional MRI experiment to test the hypothesis that the lateral prefrontal cortex and lateral occipito-temporal cortex are critical for the integration processes for social contingency. Twenty-four adults performed right finger gestures and then observed them as feedback. We manipulated three parameters of visual feedback: action kinematics (same or different gestures), body identity (self or other), and feedback timing (simultaneous or delayed). Three-way interactions of these factors were observed in the left inferior and middle frontal gyrus (IFG/MFG). These areas were active when self-actions were directly fed back in real-time (i.e., the condition causing a sense of agency), and when participants observed gestures performed by others after a short delay (i.e., the condition causing social contingency). In contrast, the left extrastriate body area (EBA) was sensitive to the concordance of action kinematics regardless of body identity or feedback timing. Body identity × feedback timing interactions were observed in regions including the superior parietal lobule (SPL). An effective connectivity analysis supported the model wherein experimental parameters modulated connections from the occipital cortex to the IFG/MFG via the EBA and SPL. These results suggest that both social contingency and the sense of agency are achieved by hierarchical processing that begins with simple concordance coding in the left EBA, leading to the complex coding of social relevance in the left IFG/MFG.Published versio