Статті в журналах: "PCTRAN"

1

Liu, Bing, Jichong Lei, Jinsen Xie, and Jianliang Zhou. "Development and Validation of a Nuclear Power Plant Fault Diagnosis System Based on Deep Learning." Energies 15, no. 22 (November 17, 2022): 8629. http://dx.doi.org/10.3390/en15228629.

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As artificial intelligence technology has progressed, numerous businesses have used intelligent diagnostic technology. This study developed a deep LSTM neural network for a nuclear power plant to defect diagnostics. PCTRAN is used to accomplish data extraction for distinct faults and varied fault degrees of the PCTRAN code, and some essential nuclear parameters are chosen as feature quantities. The training, validation, and test sets are collected using random sampling at a ratio of 7:1:2, and the proper hyperparameters are selected to construct the deep LSTM neural network. The test findings indicate that the fault identification rate of the nuclear power plant fault diagnostic model based on a deep LSTM neural network is more than 99 percent, first validating the applicability of a deep LSTM neural network for a nuclear power plant fault-diagnosis model.

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2

Cheng, Yi-Hsiang, Chunkuan Shih, Show-Chyuan Chiang, and Tong-Li Weng. "ICONE15-10001 Atmospheric Puff Model Developments in PCTRAN." Proceedings of the International Conference on Nuclear Engineering (ICONE) 2007.15 (2007): _ICONE1510. http://dx.doi.org/10.1299/jsmeicone.2007.15._icone1510_1.

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3

Anam, Muhammad Khoirul, Dwi Priyantoro, and Syarip Syarip. "PENGATURAN POSISI CONTROL RODS UNTUK MELANJUTKAN OPERASI HTGR PASCA SCRAM DENGAN SIMULATOR PCTRAN-HTR." Jurnal Forum Nuklir 13, no. 2 (December 29, 2019): 45. http://dx.doi.org/10.17146/jfn.2019.13.2.5041.

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PENGATURAN POSISI CONTROL RODS UNTUK MELANJUTKAN OPERASI HTGR PASCA SCRAM DENGAN SIMULATOR PCTRAN-HTR. Reaktivitas pada reaktor HTGR diatur dengan batang kendali (CR) yang terdiri dari 16 pasang yang terbagi menjadi dua bagian, yaitu 7 pasang di tengah teras reaktor dan 9 pasang di bagian tepi moderator. Ketika kondisi abnormal terjadi CR secara otomatis akan jatuh tersisip ke dalam teras reaktor sehingga reaktor SCRAM dan berada pada kondisi subkritis. Untuk melanjutkan operasi reaktor pasca SCRAM diperlukan analisis terkait pengaruh reaktivitas negatif dari Xenon dan suhu. Pada penelitian ini telah berhasil dilakukan simulasi penentuan posisi CR yang optimal menggunakan PCTRAN-HTR untuk melanjutkan operasi reaktor dalam dua tingkat daya, yaitu daya rendah (RDE) dengan daya 10 MWth dan daya tinggi 200 MWth. Kedua tingkat daya tersebut dicapai dengan menarik CR ke posisi tertentu sampai kondisinya kritis lagi. Hasil yang telah diperoleh menunjukkan bahwa dengan posisi CR 52 % naik sudah bisa menghasilkan kondisi superkritis untuk daya RDE dan dengan posisi 57 % dan 58 % naik, untuk daya tinggi sehingga status operasi dari start (S) bisa diganti power (P).

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4

Cheng, Yi-Hsiang, Chunkuan Shih, Show-Chyuan Chiang, and Tung-Li Weng. "Introducing PCTRAN as an evaluation tool for nuclear power plant emergency responses." Annals of Nuclear Energy 40, no. 1 (February 2012): 122–29. http://dx.doi.org/10.1016/j.anucene.2011.10.016.

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5

Ihrayz, Ezeddin A. M. Ben. "PCTRAN Westinghouse AP1000 Power Control of Pressurized Water Reactor Using Simulink of MATLAB." Open Journal of Energy Efficiency 12, no. 02 (2023): 25–35. http://dx.doi.org/10.4236/ojee.2023.122003.

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6

Chen, Chun-Yu, Wei-Yi Yang, Chunkuan Shih, and Hui-Wen Huang. "ICONE15-10199 THE IMPROVEMENTS AND MODIFICATIONS OF EMERGENCY CORE COOLING SYSTEMS IN PCTRAN-ABWR." Proceedings of the International Conference on Nuclear Engineering (ICONE) 2007.15 (2007): _ICONE1510. http://dx.doi.org/10.1299/jsmeicone.2007.15._icone1510_92.

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7

Po, Li-Chi Cliff. "Analysis of the Rancho Seco Overcooling Event Using PCTRAN, the Personal Computer Transient Analyzer." Nuclear Science and Engineering 98, no. 2 (February 1988): 154–61. http://dx.doi.org/10.13182/nse88-a28495.

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8

Saha, Arnob, Nashiyat Fyza, Altab Hossain, and M. A. Rashid Sarkar. "Simulation of tube rupture in steam generator and transient analysis of VVER-1200 using PCTRAN." Energy Procedia 160 (February 2019): 162–69. http://dx.doi.org/10.1016/j.egypro.2019.02.132.

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9

Wang, Ting Yi, Yu Ting Hsu, Shao Wen Chen, Jong Rong Wang, Chun Kuan Shih, Show Chyuan Chiang, and Tzu Yao Yu. "The Analysis of Effectiveness of BWR/6 URG Strategies." Applied Mechanics and Materials 865 (June 2017): 701–6. http://dx.doi.org/10.4028/www.scientific.net/amm.865.701.

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After the Fukushima Daichii accidents, Taiwan Power Company developed a strategy to cope with such extended SBO (Station Blackout) cases at nuclear power plants, which called URG. The MAAP and PCTRAN were used to perform the study for Kuosheng BWR/6 nuclear power plant (NPP) ultimate response guideline (URG). The main actions of URG are the depressurization and low pressure water injection of the reactor and the venting of the containment. This study focuses to confirm the URG efficiency. The analysis results depict that following the URG, the fuel can be covered by the coolant, no exposure. It can also prevent the radiation release and the large evacuation. It indicated that Kuosheng NPP was at the safe situation. It shows that the two-step depressurizations can extend the time of the preparation of alternate water source. The minimum injection rate to prevent the fuel to expose is 192 gpm in MAAP.

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10

Mahal, Jannat, Altab Hossain, Intisher Al Tahmid Omi, and Miskat Islam Anika. "Analysis of a pressurised water reactor-based nuclear accident using PCTRAN simulator and fuzzy expert system." International Journal of Nuclear Energy Science and Technology 14, no. 4 (2020): 310. http://dx.doi.org/10.1504/ijnest.2020.10041177.

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11

Hossain, Altab, Intisher Al Tahmid Omi, Miskat Islam Anika, and Jannat Mahal. "Analysis of a pressurised water reactor-based nuclear accident using PCTRAN simulator and fuzzy expert system." International Journal of Nuclear Energy Science and Technology 14, no. 4 (2020): 310. http://dx.doi.org/10.1504/ijnest.2020.117701.

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12

Sheta, A. A., E. H. Ali, R. M. Fikry, T. A. Mahmoud, S. M. El-Araby, and M. I. Mahmoud. "Intelligent Control for Pressurizer System in Nuclear Power Plants." Journal of Physics: Conference Series 2128, no. 1 (December 1, 2021): 012022. http://dx.doi.org/10.1088/1742-6596/2128/1/012022.

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Abstract Fine control of output power for nuclear power plants is the essential goal for safe operation. In this work, a Fuzzy analytical proportional-integral-derivative (FPID) controller with different configurations is designed to adjust and control the pressure of the PZR system. The stability analysis of the FPID controller with variable gains is established, and conditions for bounded-input bounded-output stability conditions (BIBO) are derived using the small gain theory. Two scenarios are applied for evaluating the dynamic response of applied controllers. In addition, performance indices are compared between the PZR model and data measured from the PCtran VVER-1200 simulator. Finally, a simulation platform is developed for MATLAB / Simulink to implement the three-region nonlinear non-equilibrium PZR model and the designed pressure controllers. The analysis and evaluation results showed good durability of the designed controllers and satisfactory performance of the control. These results further show that the nonlinear PZR model is accurate, feasible, and valuable for dynamic simulation and control unit design.

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13

Qin, Liming, Xiaohua Yang, Jie Liu, and Jiayu Ma. "Research on Diagnosis of Loss of Flow Accidents in Nuclear Reactor Coolant System." Journal of Physics: Conference Series 2242, no. 1 (April 1, 2022): 012032. http://dx.doi.org/10.1088/1742-6596/2242/1/012032.

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Abstract The reactor coolant system is one of the most important systems in a nuclear power plant. The safe and stable operation of the reactor coolant system is related to the safety of the nuclear power plant. With the rapid development of nuclear power technology, it is particularly important to ensure the safety of nuclear power plants. This paper takes the third-generation reactor AP1000 as the research object, firstly analyzes the typical accidents of the coolant system, and establishes a three-layer fault model, and then introduces the counterfactual reasoning method to take the Loss of Flow Accident as an example to identify the accident, and compares it with the traditional data-driven The Bayesian network diagnosis method was compared with the Bayesian network diagnosis method, and finally the accident was diagnosed by the simulation software Pctran. The results show that the method can accurately identify the fault and is better than the Bayesian method, which can provide decision support for accident handling and ensure the safety of the reactor.

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14

Omar, Salauddin, and Mohammad Nasim Hasan. "A PCTRAN BASED ANALYSIS ON THE EFFECT OF BREAKSIZE AND COMPARATIVE STUDY BETWEEN HOT AND COLD LEG LOSS OF COOLANT ACCIDENTS IN VVER 1200 POWER REACTOR." Acta Mechanica Malaysia 5, no. 2 (2022): 31–34. http://dx.doi.org/10.26480/amm.02.2022.31.34.

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In this paper, a comparative analysis of loss of coolant accident (LOCA) in hot leg and cold leg of primary circuit in a VVER 1200 nuclear power plant is investigated. The effect of break size on the severity of the accident is observed. The break size was varied in the range 200-11350 cm2. For all the accident scenarios, station blackout (SBO) condition is set up. Additionally, it is assumed that no ECCS (Emergency Core Cooling System) is available due to system malfunction. The whole scenario is simulated in PCTRAN (Personal Computer Transient Analyzer) software. Results reveal that with the increase in the size of the break area, the core uncovering time decreases sharply. However, for a break size of 2800 cm2 or smaller, the water level in the core doesn’t drop to zero, indicating that the core is partially uncovered throughout the accident scenario. In case of hot leg LOCA, the draining of the reactor vessel is observed to be more rapid compared to cold leg LOCA, while the core melting started earlier in case of cold leg.

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15

Hadad, K., and M. Esmaeili-Sanjavanmareh. "PCTRAN enhancement for large break loss of coolant accident concurrent with loss of offsite power in VVER-1000 simulation." Kerntechnik 82, no. 2 (April 27, 2017): 176–83. http://dx.doi.org/10.3139/124.110649.

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16

Chiang, Yu, Shao-Wen Chen, Jong-Rong Wang, Ting-Yi Wang, Hsiung-Chih Chen, Wen-Sheng Hsu, Show-Chyuan Chiang, and Chunkuan Shih. "Code crosswalk of Fukushima-like simulations for Chinshan BWR/4 NPP using MELCOR2.1/SNAP, TRACE/SNAP, PCTRAN and MAAP5.03." Nuclear Engineering and Design 325 (December 2017): 12–24. http://dx.doi.org/10.1016/j.nucengdes.2017.09.023.

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17

Gu, Haixia, Gaojun Liu, Jixue Li, Hongyun Xie, and Hanguan Wen. "A Framework Based on Deep Learning for Predicting Multiple Safety-Critical Parameter Trends in Nuclear Power Plants." Sustainability 15, no. 7 (April 6, 2023): 6310. http://dx.doi.org/10.3390/su15076310.

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Operators in the main control room of a nuclear power plant have a crucial role in supervising all operations, and any human error can be fatal. By providing operators with information regarding the future trends of plant safety-critical parameters based on their actions, human errors can be detected and prevented in a timely manner. This paper proposed a Sequence-to-Sequence (Seq2Seq)-based Long Short-Term Memory (LSTM) model to predict safety-critical parameters and their future trends. The PCTran was used to extract data for four typical faults and fault levels, and eighty-six parameters were selected as characteristic quantities. The training, validation, and testing sets were collected in a ratio of 13:3:1, and appropriate hyperparameters were used to construct the Seq2Seq neural network. Compared with conventional deep learning models, the results indicated that the proposed model could successfully solve the complex problem of the trend estimation of key system parameters under the influence of operator action factors in multiple abnormal operating conditions. It is believed that the proposed model can help operators reduce the risk of human-caused errors and diagnose potential accidents.

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18

Wang, Li, Wentao Sun, Jie Zhao, and Dichen Liu. "A Speed-Governing System Model with Over-Frequency Protection for Nuclear Power Generating Units." Energies 13, no. 1 (December 31, 2019): 173. http://dx.doi.org/10.3390/en13010173.

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Overspeed is more likely to occur in the process of load rejection or large disturbances for nuclear steam turbines due to the large parameter range and low steam parameters, as well as the power of the low-pressure cylinder accounting for a high proportion of the total power. It is of great significance to study the overspeed characteristics of nuclear power plants (NPPs) to ensure the safe and stable operation of the unit and power grid. According to the characteristics of NPPs, the overspeed protection model and the super-acceleration protection model were established, which were added to the speed-governing system model. The response characteristics of the reactor, thermal system, steam turbine and speed-governing system in the process of load rejection or large disturbances of the power grid were analyzed and simulated. The results were compared using the simulation software personal computer transient analyzer (PCTRAN). The simulation results showed that quickly closing both the high and medium pressure regulating valves could effectively realize frequency control when load rejection or a large grid disturbance occurred. The over-acceleration protection cooperates with the super-acceleration protection to avoid the repeated opening/closing of the valves due to overspeed protection. This could effectively reduce the impact of large disturbances on the reactor, thermal system, and turbine.

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19

Dwi Priyantoro, Syarip, Khoirul Anam,. "ANALISIS PENGATURAN POSISI CONTROL RODS PADA KONSEP REAKTOR DAYA EKSPERIMENTAL INDONESIA PASCA REACTOR SCRAM." GANENDRA Majalah IPTEK Nuklir 19, no. 2 (October 27, 2016): 75. http://dx.doi.org/10.17146/gnd.2016.19.2.3008.

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ANALISISPENGATURAN POSISI CONTROL RODS PADA KONSEP REAKTOR DAYA EKSPERIMENTAL INDONESIA PASCA REACTOR SCRAM POST REACTOR SCRAM CONTROL RODS POSITION ADJUSTMENT ANALYSIS FOR THE INDONESIAN EXPERIMENTAL POWER REACTOR CONCEPT. ABSTRAK ANALISIS PENGATURAN POSISI CONTROL RODS PADA KONSEP REAKTOR DAYA EKSPERIMENTAL INDONESIA PASCA REACTOR SCRAM. Telah dilakukan analisis simulasi pengaturan posisi batang-batang kendali untuk melanjutkan operasi reaktor daya eksperimental (RDE) paska scram setelah beroperasi pada periode waktu tertentu. Pengendalian reaktivitas pada reaktor RDE yang akan dibangun di Indonesia dengan rujukan high temperature gas reactor (HTR) 10 MWt, dilakukan dengan 10 pasang batang-batang kendali atau control rod (CR). Apabila terrjadi kondisi abnormal maka CR secara otomatis akan jatuh tersisip ke dalam reflektor reaktor sehingga reaktor scram dan berada pada kondisi subkritis. Untuk melanjutkan operasi reaktor pasca scram diperlukan analisis terkait pengaruh reaktivitas negatif dari Xenon dan suhu. Pada makalah ini disajikan hasil simulasi yang dilakukan untuk penentuan posisi CR paling optimum untuk melanjutkan operasi reaktor, menggunakan simulator PCTRAN-HTR. Simulasi dilakukan pada variasi 70%, 85% dan 100% dari tingkat daya penuh dan dengan variasi waktu operasi 50 s, 10.000 s, dan 20.000 s di mana setelah reaktor beroperasi pada tingkat-tingkat daya dan waktu operasi tersebut reaktor mengalami scram. Untuk melanjutkan operasi lagi maka CR harus dinaikkan lagi dan diatur ke posisi tertentu sampai reaktor mencapai kondisi kritis lagi pada tingkat daya nominal tersebut. Hasil yang telah diperoleh menunjukkan bahwa dengan posisi CR naik 52 % sudah bisa menghasilkan kondisi kritis dan mampu mengatasi reaktivitas negatif peracunan xenon maupun suhu. Kata kunci: RDE, HTR, operasi reaktor, batang kendali, reaktivitas, scram ABSTRACT POST REACTOR SCRAM CONTROL RODS POSITION ADJUSTMENT ANALYSIS FOR THE INDONESIAN EXPERIMENTAL POWER REACTOR CONCEPT. Analytical study using PC-based simulator has been carried out on control rods position adjustment of the Indonesian experimental power reactor concept or reaktor daya ekperimental (RDE) in a post reactor scram to continue operation after a certain operation period. Reactivity control of the RDE uses 10 pairs of control rods (CRs), which is based on that applied in the high temperature gas reactor (HTR) 10 MW(t). If an abnormal operating condition occurs, these control rods automatically dropped to the reflector that bring the reactor into a scram and subcritical condition. To continue reactor operation after a period of time, the CRs should be withdrawn to achieve recriticality. Prior to any CRs withdrawal, an analysis of negative reactivity effects of Xenon (poissoning) and fuel temperature coefficient should be done. Simulations using PCTRAN-HTR simulator to determine the optimum CRs positions in achieving reactor criticality for continuation of reactor operation is presented in this paper. The simulations were conducted by varying the reactor power levels at 70%, 85% and 100% of full power, respectively. The reactor operation time was varied at 50s, 10000s, and 20000 s prior to the reactor scram. Adjustment of CRs position should be done to continue reactor operation at those nominal power levels by withdrawing the CRs to the proper positions. The simulation results show that recriticality can be achieverd by whitdrawing the CRs 52% of farther and the negative reactivity from xenon poisoning and temperature could be overcome. Keywords : RDE, HTR, reactor operation, control rod, reactivity, scram.

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20

Khan, Abid Hossain, and Md Shafiqul Islam. "A PCTRAN-BASED INVESTIGATION ON THE EFFECT OF INADVERTENT CONTROL ROD WITHDRAWAL ON THE THERMAL-HYDRAULIC PARAMETERS OF A VVER-1200 NUCLEAR POWER REACTOR." Acta Mechanica Malaysia 2, no. 2 (October 10, 2019): 32–38. http://dx.doi.org/10.26480/amm.02.2019.32.38.

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21

Nath, Pronob Deb, Kazi Mostafijur Rahman, and Md Abdullah Al Bari. "Thermal Hydraulic Analysis of a Nuclear Reactor due to Loss of Coolant Accident with and without Emergency Core Cooling System." Journal of Engineering Advancements 01, no. 02 (June 29, 2020): 53–60. http://dx.doi.org/10.38032/jea.2020.02.004.

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This paper evaluates the thermal hydraulic behavior of a pressurized water reactor (PWR) when subjected to the event of Loss of Coolant Accident (LOCA) in any channel surrounding the core. The accidental break in a nuclear reactor may occur to circulation pipe in the main coolant system in a form of small fracture or equivalent double-ended rupture of largest pipe connected to primary circuit line resulting potential threat to other systems, causing pressure difference between internal parts, unwanted core shut down, explosion and radioactivity release into environment. In this computational study, LOCA for generation III+ VVER-1200 reactor has been carried out for arbitrary break at cold leg section with and without Emergency Core Cooling System (ECCS). PCTRAN, a thermal hydraulic model-based software developed using real data and computational approach incorporating reactor physics and control system was employed in this study. The software enables to test the consequences related to reactor core operations by monitoring different operating variables in the system control bar. Two types of analysis were performed -500% area break at cold leg pipe due to small break LOCA caused by malfunction of the system with and without availability of ECCS. Thermal hydraulic parameters like, coolant dynamics, heat transfer, reactor pressure, critical heat flux, temperature distribution in different sections of reactor core have also been investigated in the simulation. The flow in the reactor cooling system, steam generators steam with feed-water flow, coolant steam flow through leak level of water in different section, power distribution in core and turbine were plotted to analyze their behavior during the operations. The simulation showed that, LOCA with unavailability of Emergency Core Cooling System (ECCS) resulted in core meltdown and release of radioactivity after a specific time.

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22

Khan, Abid Hossain, Angkush Kumar Ghosh, Md Sumon Rahman, S. M. Tazim Ahmed, and C. L. Karmakar. "An Investigation on the Possible Radioactive Contamination of Environment during a Steam-Line Break Accident in a VVER-1200 Nuclear Power Plant." Current World Environment 14, no. 2 (August 16, 2019): 299–311. http://dx.doi.org/10.12944/cwe.14.2.14.

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In this work, the possibility of contamination of environment by radioactive elements due to a steam-line break accident has been investigated for a VVER-1200 type nuclear power plant. Personal Computer Transient Analyzer (PCTRAN) has been used to generate the response data of the plant safety systems numerically for an accidental condition like such. A break of 1000 cm2 in the A-loop of the steam line has been considered. A break of the size is considered a “Large Break”, which is believed to be responsible for multiple serious accidents in the past. Also, it has also been assumed that off-site AC power supply is unavailable. Simulations were run for time duration of 300 seconds since most of the safety features of the plant should respond within 50 seconds from the initiation of the accident. Results show that SCRAM is initiated within 22.5 seconds from the emergence of the break, which limited the peak core thermal power to around 105% of the nominal value. The peak temperatures of fuel elements and fuel cladding are recorded to be around 1850oC and 620oC respectively, which are both within the safety limits. The pressure inside reactor pressure vessel has not undergone any significant changes, showing no sign of failure. Again, the pressure inside the reactor containment building is kept within 2.5 bar by the safety systems, indicating that there is no possibility of containment failure due to over-pressure. Finally, the readings from radiation monitor show that there is no noticeable release of radioactive elements to the environment during the accident. Therefore, it may be concluded that the release of radioactive elements in the surrounding environment during a steam-line break accident is very unlikely provided that the plant safety systems are fully functional.

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23

Zhang, Chunyuan, Pengyu Chen, Fangling Jiang, Jinsen Xie, and Tao Yu. "Fault Diagnosis of Nuclear Power Plant Based on Sparrow Search Algorithm Optimized CNN-LSTM Neural Network." Energies 16, no. 6 (March 22, 2023): 2934. http://dx.doi.org/10.3390/en16062934.

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Nuclear power is a type of clean and green energy; however, there is a risk of radioactive material leakage when accidents occur. When radioactive material leaks from nuclear power plants, it has a great impact on the environment and personnel safety. In order to enhance the safety of nuclear power plants and support the operator’s decisions under accidental circumstances, this paper proposes a fault diagnosis method for nuclear power plants based on the sparrow search algorithm (SSA) optimized by the CNN-LSTM network. Firstly, the convolutional neural network (CNN) was used to extract features from the data before they were then combined with the long short-term memory (LSTM) neural network to process time series data and form a CNN-LSTM model. Some of the parameters in the LSTM neural network need to be manually tuned based on experience, and the settings of these parameters have a great impact on the overall model results. Therefore, this paper selected the sparrow search algorithm with a strong search capability and fast convergence to automatically search for the hand-tuned parameters in the CNN-LSTM model, and finally obtain the SSA-CNN-LSTM model. This model can classify the types of accidents that occur in nuclear power plants to reduce the nuclear safety hazards caused by human error. The experimental data are from a personal computer transient analyzer (PCTRAN). The results show that the classification accuracy of the SSA-CNN-LSTM model for the nuclear power plant fault classification problem is as high as 98.24%, which is 4.80% and 3.14% higher compared with the LSTM neural network and CNN-LSTM model, respectively. The superiority of the sparrow search algorithm for optimizing model parameters and the feasibility and accuracy of the SSA-CNN-LSTM model for nuclear power plant fault diagnosis were verified.

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24

Pieper, Galen M., Cara L. Olds, Jeffrey D. Bub та Paul F. Lindholm. "Transfection of human endothelial cells with HIV-1tatgene activates NF-κB and enhances monocyte adhesion". American Journal of Physiology-Heart and Circulatory Physiology 283, № 6 (1 грудня 2002): H2315—H2321. http://dx.doi.org/10.1152/ajpheart.00469.2002.

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Human immunodeficiency virus (HIV)-1 Tat released from HIV-1-infected monocytes is believed to enter other cells via an integrin-facilitated pathway, resulting in altered gene expression. Indeed, exogenous Tat protein can increase cell adhesion molecule gene expression in human endothelial cells. Signaling pathways initiated by Tat in endothelial cells are not known. We evaluated the ability of endogenous tat to stimulate monocyte adhesion via activation of nuclear factor-κB (NF-κB) within human umbilical vein endothelial cells. Transfection with pcTat, but not control vector DNA, increased NF-κB binding activity, NF-κB luciferase reporter activity, and monocyte adhesion. pcTat also increased κB-dependent HIV-1-LTR-CAT reporter activity 28-fold compared with a 3-fold increase produced by transfection with an equivalent amount of pcTax (from human leukemia virus). The pcTat-induced increase in pNF-κB-Luc activity and monocyte adhesion to endothelial cells was blocked by cotransfection with dominant-negative mutant IκBα and by incubation with 10 mM aspirin. We conclude that monocyte adhesion to human endothelial cells stimulated by pcTat is mediated via an NF-κB-dependent mechanism. Furthermore, inhibition studies using aspirin suggest that pcTat-stimulated NF-κB activation and monocyte adhesion occur via a redox-sensitive mechanism.

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25

Zuo, Chenpeng, Hetong Wang, Wenxiao Pan, Siyuan Zheng, Fei Xu, and Qingzhu Zhang. "Quantum Chemical and Kinetic Study on Radical/Molecule Formation Mechanism of Pre-Intermediates for PCTA/PT/DT/DFs from 2-Chlorothiophenol and 2-Chlorophenol Precursors." International Journal of Molecular Sciences 20, no. 7 (March 27, 2019): 1542. http://dx.doi.org/10.3390/ijms20071542.

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Polychlorinated phenoxathiins (PCPTs), polychlorinated dibenzothiophenes (PCDTs), and polychlorinated thianthrenes (PCTAs) are sulfur analogues of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/DFs). Chlorothiophenols (CTPs) and chlorophenols (CPs) are key precursors for the formation of PCTA/PT/DTs, which can react with H or OH to form chloro(thio)phenoxy radical, sulfydryl/hydroxyl-substituted phenyl radicals, and (thio)phenoxyl diradicals. However, previous radical/radical PCTA/DT formation mechanisms in the literature failed to explain the higher concentration of PCDTs than that of PCTAs under the pyrolysis or combustion conditions. In this work, a detailed thermodynamics and kinetic calculations were carried out to investigate the pre-intermediate formation for PCTA/PT/DTs from radical/molecule coupling of the 2-C(T)P with their key radical species. Our study showed that the radical/molecule coupling mechanism explains the gas-phase formation of PCTA/PT/DTs in both thermodynamic and kinetic perspectives. The S/C coupling modes to form thioether-(thio)enol intermediates are preferable over the O/C coupling modes to form ether-(thio)enol intermediates. Thus, although the radical/molecule coupling of chlorophenoxy radical with 2-C(T)P has no effect on the PCDD/PT formation, the radical/molecule coupling of chlorothiophenoxy radical with 2-C(T)P plays an important role in the PCTA/PT formation. Most importantly, the pre-PCDT intermediates formation pathways from the couplings of sulfydryl/hydroxyl-substituted phenyl radical with 2-C(T)P and (thio)phenoxyl diradicals with 2-C(T)P are more favorable than pre-PCTA/PT intermediates formation pathways from the coupling of chlorothiophenoxy radical with 2-C(T)P, which provides reasonable explanation for the high PCDT-to-PCTA ratio in the environment.

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El-Hameed, Ahmed Abd, and Juyoul Kim. "Machine Learning-Based Classification and Regression Approach for Sustainable Disaster Management: The Case Study of APR1400 in Korea." Sustainability 13, no. 17 (August 30, 2021): 9712. http://dx.doi.org/10.3390/su13179712.

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During nuclear accidents, decision-makers need to handle considerable data to take appropriate protective actions to protect people and the environment from radioactive material release. In such scenarios, machine learning can be an essential tool in facilitating the protection action decisions that will be made by decision-makers. By feeding machines software with big data to analyze and identify nuclear accident behavior, types, and the concentrations of released radioactive materials can be predicted, thus helping in early warning and protecting people and the environment. In this study, based on the ground deposition concentration of radioactive materials at different distances offsite in an emergency planning zone (EPZ), we proposed classification and regression models for three severe accidents. The objective of the classification model is to recognize the transient situation type for taking appropriate actions, while the objective of the regression model is to estimate the concentrations of the released radioactive materials. We used the Personal Computer Transient Analyser (PCTRAN) Advanced Power Reactor (APR) 1400 to simulate three severe accident scenarios and to generate a source term released to the environment. Additionally, the Radiological Consequence Analysis Program (RCAP) was used to assess the off-site consequences of nuclear power plant accidents and to estimate the ground deposition concentrations of radionuclides. Moreover, ground deposition concentrations at different distances were used as input data for the classification and regression tree (CART) models to obtain an accident pattern and to establish a prediction model. Results showed that the ground deposition concentration at a near distance from a nuclear power plant is a more informative parameter in predicting the concentration of radioactive material release, while the ground deposition concentration at a far distance is a very informative parameter in identifying accident types. In the regression model, the R-square of the training and test data was 0.995 and 0.994, respectively, showing a mean strong linear relationship between the predicted and actual concentration of radioactive material release. The mean absolute percentage error was found to be 26.9% and 28.1% for the training and test data, respectively. In the classification model, the model predicted a scenario (1) of 99.8% and 98.9%, scenario (2) of 98.4% and 91.6%, and scenario (3) of 98.6% and 94.7% for the training and test data, respectively.

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Schwartz, Isaac E., Gregory G. Capra, David P. Mullin, Terence E. Johnson, and Gilbert E. Boswell. "Parathyroid Computed Tomography Angiography: Early Experience with a Novel Imaging Technique in Primary Hyperparathyroidism." Otolaryngology–Head and Neck Surgery 161, no. 2 (April 9, 2019): 251–56. http://dx.doi.org/10.1177/0194599819842106.

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Objectives To describe parathyroid computed tomography angiography (PCTA), determine its accuracy, and, as a secondary objective, calculate its mean radiation dosimetry. Study Design Retrospective chart review of patients who underwent parathyroidectomy for primary hyperparathyroidism from 2007 to 2015. Setting Single-center tertiary care academic military hospital. Subjects and Methods PCTA is a 2-phase computed tomography imaging technique that uses individualized timing of contrast infusion and novel patient positioning to accurately identify parathyroid adenomas. Consecutive patients who underwent parathyroidectomy for primary hyperparathyroidism from 2007 to 2015 were reviewed; 55% of patients were women. The mean age was 50.9 years (range, 26-68 years). Sensitivity and specificity were calculated as well as mean radiation dosimetry and timing of contrast. Results A total of 108 procedures were performed during the study period. Twenty-one patients undergoing 22 PCTAs after prior sestamibi scans were nonlocalizing or equivocal. In this group, there were 15 true-positive, 3 false-positive, 4 true-negative, and 0 false-negative PCTAs. This represents a sensitivity of 100% (95% CI, 74.7%-100%) and a specificity of 57% (95% CI, 20%-88%). The mean calculated radiation dose was 5.15 mSv. In the most recent studies, a mean dose of 4.1 mSv was calculated. The ideal time of image acquisition contrast administration varied from 20 to 30 seconds after contrast infusion. Conclusions PCTA is a new technique in anatomic imaging for hyperparathyroidism. In a single-center, single-radiologist retrospective study, it demonstrates excellent accuracy for patients with parathyroid adenomas that are otherwise difficult to localize preoperatively. Preliminary experience suggests that its use may be indicated as a primary imaging modality in the future.

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Wang, Hetong, Chenpeng Zuo, Siyuan Zheng, Yanhui Sun, Fei Xu, and Qingzhu Zhang. "Mechanistic and Kinetic Study on Self-/Cross- Condensation of PCTA/DT Formation Mechanisms from Three Types of Radicals of 2,4-Dichlorothiophenol." International Journal of Molecular Sciences 20, no. 11 (May 28, 2019): 2623. http://dx.doi.org/10.3390/ijms20112623.

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Chlorothiophenols (CTPs) are known to be key and direct precursors of polychlorinated thianthrene/dibenzothiophenes (PCTA/DTs). Self/cross-coupling of the chlorothiophenoxy radicals (CTPRs), sulfydryl-substituted phenyl radicals and thiophenoxyl diradicals evolving from CTPs are initial and important steps for PCTA/DT formation. In this study, quantum chemical calculations were carried out to investigate the homogenous gas-phase formation of PCTA/DTs from self/cross-coupling of 2,4-dichlorothiophenoxy radical (R1), 2-sulfydryl-3,5-dichlorophenyl radical (R2) and 3,5-dichlorothiophenoxyl diradical (DR) at the MPWB1K/6-311+G(3df,2p)//MPWB1K/6-31+G(d,p) level. The rate constants of crucial elementary steps were deduced over 600–1200 K, using canonical variational transition state theory with a small curvature tunneling contribution. For the formation of PCTAs, the S•/σ-C• condensation with both thiophenolic sulfur in one radical and ortho carbon in the other radical bonded to single electron is the most efficient sulfur-carbon coupling mode, and the ranking of the PCTA formation potential is DR + DR > R2 + DR > R1 + DR > R1 + R2 > R1 + R1. For the formation of PCDTs, the σ-C•/σ-C• coupling with both ortho carbon in the two radicals bonded to single electron is the energetically favored carbon-carbon coupling mode, and the ranking of the PCDT formation potential is: R2 + DR > R2 + R2 > R1 + DR > R1 + R2 > R1 + R1. The PCTA/DTs could be produced from R1, R2 and DR much more readily than PCDD/DFs from corresponding oxygen substituted radicals.

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Kim, Young Chan, Barbara Dema, Roberto Rodriguez-Garcia, César López-Camacho, Fabiana M. S. Leoratti, Amar Lall, Edmond J. Remarque, Clemens H. M. Kocken, and Arturo Reyes-Sandoval. "Evaluation of Chimpanzee Adenovirus and MVA Expressing TRAP and CSP from Plasmodium cynomolgi to Prevent Malaria Relapse in Nonhuman Primates." Vaccines 8, no. 3 (July 6, 2020): 363. http://dx.doi.org/10.3390/vaccines8030363.

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Plasmodium vivax is the world’s most widely distributed human malaria parasite, with over 2.8 billion people at risk in Asia, the Americas, and Africa. The 80–90% new P. vivax malaria infections are due to relapses which suggest that a vaccine with high efficacy against relapses by prevention of hypnozoite formation could lead to a significant reduction in the prevalence of P. vivax infections. Here, we describe the development of new recombinant ChAdOx1 and MVA vectors expressing P. cynomolgi Thrombospondin Related Adhesive Protein (PcTRAP) and the circumsporozoite protein (PcCSP). Both were shown to be immunogenic in mice prior to their assessment in rhesus macaques. We confirmed good vaccine-induced humoral and cellular responses after prime-boost vaccination in rhesus macaques prior to sporozoite challenge. Results indicate that there were no significant differences between mock-control and vaccinated animals after challenge, in terms of protective efficacy measured as the time taken to 1st patency, or as number of relapses. This suggests that under the conditions tested, the vaccination with PcTRAP and PcCSP using ChAdOx1 or MVA vaccine platforms do not protect against pre-erythrocytic malaria or relapses despite good immunogenicity induced by the viral-vectored vaccines.

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Okayasu, Mitsuhiro, Shuhei Takeuchi, and Hiroaki Ohfuji. "Mechanical Strength and Failure Characteristics of Cast Mg-9 pctAl-1 pctZn Alloys Produced by a Heated-Mold Continuous Casting Process: Tensile Properties." Metallurgical and Materials Transactions A 45, no. 12 (August 14, 2014): 5767–76. http://dx.doi.org/10.1007/s11661-014-2497-5.

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Ma, Biao, Heting Shi, Jiayun Xu, Kun Wei, Xiaoqing Wang, and Yue Xiao. "Thermal-Insulation Effect and Evaluation Indices of Asphalt Mixture Mixed with Phase-Change Materials." Materials 13, no. 17 (August 24, 2020): 3738. http://dx.doi.org/10.3390/ma13173738.

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Under strong winds and at low temperatures, heat loss of hot-mix asphalt mixtures is likely to occur, which leads to temperature segregation. Temperature segregation affects the forming quality and the performance of asphalt pavements. In this study, a phase-change thermal-insulation agent (PCTIA) was prepared for reducing the temperature dissipation. A cooling simulation experiment was performed to test the temperature-dissipation process for an ordinary asphalt mixture and the asphalt mixture mixed with PCTIA (AM-PCTIA). The thermal-insulation effect was analyzed according to the temperature difference and the thermal-insulation extension time. Moreover, two indices—the thermal-insulation accumulated time difference value (IATDV) and thermal-insulation accumulated time difference index (IATDI)—were proposed for evaluating the thermal-insulation ability and efficiency. The results indicated that the temperature at the center of the AM-PATIA was 4 °C higher than that for the ordinary asphalt mixture. The insulation time was prolonged by 29.8 min at the ambient temperature of 15 °C. As the ambient temperature increased, the thermal-insulation effect of the PCTIA improved.

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Chatsirisupachai, Jirat, Phattananawee Nalaoh, Chokchai Kaiyasuan, Pongsakorn Chasing, Taweesak Sudyoadsuk, and Vinich Promarak. "Unique dual fluorescence emission in the solid state from a small molecule based on phenanthrocarbazole with an AIE luminogen as a single-molecule white-light emissive material." Materials Chemistry Frontiers 5, no. 5 (2021): 2361–72. http://dx.doi.org/10.1039/d0qm00951b.

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New triphenylethylene-phenanthrocarbazole (PCTrPE) was the first small molecule that exhibited dual fluorescence emission in the solid state providing a new strategy to realize a single-molecule white emissive material for white OLEDs.

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Zeng, Liangen, Haitao Li, Xiao Wang, Zhao Yu, Haoyu Hu, Xinyue Yuan, Xuhai Zhao, et al. "China’s Transport Land: Spatiotemporal Expansion Characteristics and Driving Mechanism." Land 11, no. 8 (July 25, 2022): 1147. http://dx.doi.org/10.3390/land11081147.

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The literature about changes in land use includes many studies of global sustainable development goals, while studies of transport land expansion have been relatively scarce. In this paper, we present an analysis of the spatiotemporal characteristics of transport land expansion in China’s 31 provinces from 2009 to 2017, applying the spatial Dubin model to identify the factors that influenced changes in per capita transport land area (PCTLA). The eastern and western regions have continued to lead the nation in terms of the total area dedicated to transport land. The expansion speed of transport land in the central and western regions, however, has been faster than in the eastern and northeast regions. As for PCTLA, the western region had the greatest amount and the central region the least. Further, PCTLA showed significant spatial autocorrelation. Economic development, government regulations, industrial structure, and the extent of opening up and urbanization had significant positive impacts on PCTLA, while the development of railway freight had a negative impact. This paper concludes with some policy suggestions for optimizing transport investment, accelerating the adjustment of industrial structure and transport structure, and implementing high-quality urbanization. The results should be of interest to those involved in the sustainable development of transport systems.

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Mock, Beverly A., Janet Hartley, Paul Le Tissier, Judith S. Wax, and Michael Potter. "The Plasmacytoma Resistance Gene, Pctr2, Delays the Onset of Tumorigenesis and Resides in the Telomeric Region of Chromosome 4." Blood 90, no. 10 (November 15, 1997): 4092–98. http://dx.doi.org/10.1182/blood.v90.10.4092.

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Abstract Mouse plasmacytomas share pathogenetic features in common with both multiple myeloma and Burkitt's lymphoma in humans. Susceptibility to plasmacytoma induction by intraperitoneal pristane in mice is controlled by multiple genes. At least two of these genes reside on mouse chromosome 4 in regions of the genome sharing linkage homology with human chromosomes 9p21, 1p32, and 1p36. A series of congenic strains recombinant for regions of mouse chromosome 4 in the vicinity of the Pctr2 predisposition locus were created and typed for their tumor susceptibility/resistance phenotypes. These strains were derived by introgressively backcrossing alleles from resistant DBA/2 mice onto the susceptible BALB/cAnPt background. Six resistant and two susceptible strains were allelotyped for 10 genes and 49 random DNA markers to identify the smallest region of overlap in the resistant strains. These studies have determined that the Pctr2 locus resides in either a 500-kb interval proximal to Nppa, or in a 1- to 2-centiMorgan (cM) interval distal to Nppa. In these congenic strain analyses, the Nppa and Fv1 loci, in addition to genes within about 1 cM of these loci, have been excluded as candidates for the Pctr2 locus. A relevant locus that may reside in this interval is Rep2; it is associated with the efficiency of repairing X-ray induced DNA damage sustained during the G2 phase of the mitotic cycle. The Pctr2 locus acts in a codominant fashion. F1 hybrids between resistant and susceptible congenic strains exhibit a reduced tumor incidence and a significant delay in the onset of tumorigenesis. Identification and eventual cloning of the Pctr2 locus may assist in the identification of genes involved in many types of cancer showing aberrations in human chromosome 1p36.

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Chiang, Nan, Xavier de la Rosa, Stephania Libreros, Hui Pan, Jonathan M. Dreyfuss, and Charles N. Serhan. "Cysteinyl-specialized proresolving mediators link resolution of infectious inflammation and tissue regeneration via TRAF3 activation." Proceedings of the National Academy of Sciences 118, no. 10 (March 1, 2021): e2013374118. http://dx.doi.org/10.1073/pnas.2013374118.

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The recently elucidated proresolving conjugates in tissue regeneration (CTR) maresin-CTR (MCTR), protectin-CTR (PCTR), and resolvin-CTR (RCTR), termed cysteinyl-specialized proresolving mediators (cys-SPMs) each promotes regeneration, controls infection, and accelerates resolution of inflammation. Here, we sought evidence for cys-SPM activation of primordial pathways in planaria (Dugesia japonica) regeneration that might link resolution of inflammation and regeneration. On surgical resection, planaria regeneration was enhanced with MCTR3, PCTR3, or RCTR3 (10 nM), each used for RNA sequencing. The three cys-SPMs shared up-regulation of 175 known transcripts with fold-change > 1.25 and combined false discovery rate (FDR) < 0.002, and 199 canonical pathways (FDR < 0.25), including NF-κB pathways and an ortholog of human TRAF3 (TNFR-associated factor 3). Three separate pathway analyses converged on TRAF3 up-regulation by cys-SPMs. With human macrophages, three cys-SPMs each dose-dependently increased TRAF3 expression in a cAMP-PKA–dependent manner. TRAF3 overexpression in macrophages enhanced Interleukin-10 (IL-10) and phagocytosis of Escherichia coli. IL-10 also increased phagocytosis in a dose-dependent manner. Silencing of mouse TRAF3 in vivo significantly reduced IL-10 and macrophage phagocytosis. TRAF3 silencing in vivo also relieved cys-SPMs’ actions in limiting polymorphonuclear neutrophil in E. coli exudates. These results identify cys-SPM–regulated pathways in planaria regeneration, uncovering a role for TRAF3/IL-10 in regulating mammalian phagocyte functions in resolution. Cys-SPM activation of TRAF3 signaling is a molecular component of both regeneration and resolution of infectious inflammation.

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Zhang, Shuling-L., Wendy DuBois, Edward S. Ramsay, Valeri Bliskovski, Herbert C. Morse, Leki Taddesse-Heath, William C. Vass, Ronald A. DePinho, and Beverly A. Mock. "Efficiency Alleles of the Pctr1 Modifier Locus for Plasmacytoma Susceptibility." Molecular and Cellular Biology 21, no. 1 (January 1, 2001): 310–18. http://dx.doi.org/10.1128/mcb.21.1.310-318.2001.

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ABSTRACT The susceptibility of BALB/c mice to pristane-induced plasmacytomas is a complex genetic trait involving multiple loci, while DBA/2 and C57BL/6 strains are genetically resistant to the plasmacytomagenic effects of pristane. In this model system for human B-cell neoplasia, one of the BALB/c susceptibility and modifier loci, Pctr1, was mapped to a 5.7-centimorgan (cM) chromosomal region that includedCdkn2a, which encodes p16INK4a and p19ARF, and the coding sequences for the BALB/c p16INK4a and p19ARF alleles were found to be polymorphic with respect to their resistant Pctr1counterparts in DBA/2 and C57BL/6 mice (45). In the present study, alleles of Pctr1, Cdkn2a, andD4Mit15 from a resistant strain (BALB/cDAG) carrying DBA/2 chromatin were introgressively backcrossed to the susceptible BALB/c strain. The resultant C.DAG-Pctr1 Cdkn2a D4Mit15 congenic was more resistant to plasmacytomagenesis than BALB/c, thus narrowingPctr1 to a 1.5-cM interval. Concomitantly, resistant C57BL/6 mice, from which both gene products of the Cdkn2agene have been eliminated, developed pristane-induced plasma cell tumors over a shorter latency period than the traditionally susceptible BALB/cAn strain. Biological assays of the p16INK4a and p19ARF alleles from BALB/c and DBA/2 indicated that the BALB/c p16INK4a allele was less active than its DBA/2 counterpart in inducing growth arrest of mouse plasmacytoma cell lines and preventing ras-induced transformation of NIH 3T3 cells, while the two p19ARF alleles displayed similar potencies in both assays. We propose that the BALB/c susceptibility/modifier locus,Pctr1, is an “efficiency” allele of the p16INK4a gene.

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Davies, Neville, and P. G. Higginbotham. "PCTAB: An All-Purpose Statistical Package." Mathematical Gazette 74, no. 468 (June 1990): 183. http://dx.doi.org/10.2307/3619389.

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Chen, Jianchang, Yiming Chen, and Zhengjun Liu. "Classification of Typical Tree Species in Laser Point Cloud Based on Deep Learning." Remote Sensing 13, no. 23 (November 23, 2021): 4750. http://dx.doi.org/10.3390/rs13234750.

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We propose the Point Cloud Tree Species Classification Network (PCTSCN) to overcome challenges in classifying tree species from laser data with deep learning methods. The network is mainly composed of two parts: a sampling component in the early stage and a feature extraction component in the later stage. We used geometric sampling to extract regions with local features from the tree contours since these tend to be species-specific. Then we used an improved Farthest Point Sampling method to extract the features from a global perspective. We input the intensity of the tree point cloud as a dimensional feature and spatial information into the neural network and mapped it to higher dimensions for feature extraction. We used the data obtained by Terrestrial Laser Scanning (TLS) and Unmanned Aerial Vehicle Laser Scanning (UAVLS) to conduct tree species classification experiments of white birch and larch. The experimental results showed that in both the TLS and UAVLS datasets, the input tree point cloud density and the highest feature dimensionality of the mapping had an impact on the classification accuracy of the tree species. When the single tree sample obtained by TLS consisted of 1024 points and the highest dimension of the network mapping was 512, the classification accuracy of the trained model reached 96%. For the individual tree samples obtained by UAVLS, which consisted of 2048 points and had the highest dimension of the network mapping of 1024, the classification accuracy of the trained model reached 92%. TLS data tree species classification accuracy of PCTSCN was improved by 2–9% compared with other models using the same point density, amount of data and highest feature dimension. The classification accuracy of tree species obtained by UAVLS was up to 8% higher. We propose PCTSCN to provide a new strategy for the intelligent classification of forest tree species.

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Oliver, R., and J. L. Ballester. "The Prominence-Corona Transition Region and the Problem of Prominence Oscillations." International Astronomical Union Colloquium 167 (1998): 143–46. http://dx.doi.org/10.1017/s0252921100047473.

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AbstractRecent theoretical investigations of prominence oscillations indicate that the prominence-corona transition region (PCTR) may have a great influence on the magnetohydrodynamic modes of the whole system. We here consider an isothermal prominence embedded in an isothermal corona with a thin PCTR providing a smooth temperature transition between prominence and corona. The effect of the PCTR on the oscillations of the prominence body are investigated.

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Lee, Tae, In Song, Jong Shin, Yong Park, Jung Kim, Kwang Kim, Yong Lee, and Joo Kang. "PET Imaging Biomarkers of Anti-EGFR Immunotherapy in Esophageal Squamous Cell Carcinoma Models." Cells 7, no. 11 (October 27, 2018): 187. http://dx.doi.org/10.3390/cells7110187.

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Epidermal growth factor receptor (EGFR) is overexpressed and considered as a proper molecular target for diagnosis and targeted therapy of esophageal squamous cell carcinoma (ESCC). This study evaluated the usefulness of PET imaging biomarkers with 64Cu-PCTA-cetuximab and 18F-FDG-PET for anti-EGFR immunotherapy in ESCC models. In vivo EGFR status and glucose metabolism by cetuximab treatment were evaluated using 64Cu-PCTA-cetuximab and 18F-FDG-PET, respectively. Therapeutic responses with imaging biomarkers were confirmed by western blot and immunohistochemistry. TE-4 and TE-8 tumors were clearly visualized by 64Cu-PCTA-cetuximab, and EGFR expression on TE-8 tumors showed 2.6-fold higher uptake than TE-4. Tumor volumes were markedly reduced by cetuximab in TE-8 tumor (92.5 ± 5.9%), but TE-4 tumors were refractory to cetuximab treatment. The SUVs in 64Cu-PCTA-cetuximab and 18F-FDG-PET images were statistically significantly reduced by cetuximab treatment in TE-8 but not in TE-4. 64Cu-PCTA-cetuximab and 18F-FDG-PET images were well correlated with EGFR and pAkt levels. 64Cu-PCTA-cetuximab immuno-PET had a potential for determining EGFR level and monitoring therapeutic response by anti-EGFR therapy. 18F-FDG-PET was also attractive for monitoring efficacy of anti-EGFR therapy. In conclusion, PET imaging biomarkers may be useful for selecting patients that express target molecules and for monitoring therapeutic efficacy of EGFR-targeted therapy in ESCC patients.

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Matsumoto, Hiroki, Chika Igarashi, Tomoko Tachibana, Fukiko Hihara, Atsuo Waki, Ming-Rong Zhang, Sei Yoshida, et al. "Characterization and Stabilization of a New 64Cu-Labeled Anti-EGFR Antibody NCAB001 for the Early Detection of Pancreatic Cancer with Positron Emission Tomography." Pharmaceutics 14, no. 1 (December 28, 2021): 67. http://dx.doi.org/10.3390/pharmaceutics14010067.

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Early diagnosis of pancreatic cancer using current imaging modalities remains challenging. We have developed a new approach to identify tumor lesions ≥ 3 mm in the pancreas by positron emission tomography (PET) with a new intraperitoneally administered 64Cu-labeled anti-epidermal growth factor receptor (EGFR) antibody (encoded as NCAB001), called 64Cu-NCAB001 ipPET. Generally, in clinical research, a radiometal-antibody complex must be prepared immediately before use at the imaging site. To make 64Cu-NCAB001 ipPET available to daily clinical practices in a sustainable way, the NCAB001-chelator conjugate and 64Cu-NCAB001 must be characterized and stabilized. NCAB001 was manufactured under cGMP conditions. NCAB001 was conjugated with a bifunctional chelator (p-SCN-Bn-PCTA), and the antibody-chelator conjugate (PCTA-NCAB001) was characterized by LC/MS and ELISA. Thereafter, to effectively manufacture 64Cu-NCAB001, we developed a new formulation to stabilize PCTA-NCAB001 and 64Cu-NCAB001. An average of three PCTA chelators were conjugated per molecule of NCAB001. The relative binding potency of PCTA-NCAB001 was comparable to cetuximab. The formulation consisting of acetate buffer, glycine, and polysorbate-80 stabilized PCTA-NCAB001 for a year-long storage. Additionally, this formulation enabled the stabilization of 64Cu-NCAB001 for up to 24 h after radiolabeling with a sufficient radioactivity concentration for clinical use. These results may accelerate the future use of 64Cu-NCAB001 ipPET in clinical settings for the early diagnosis and treatment of pancreatic cancer.

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Abdullah, Mukhammad. "Kontribusi Nilai-nilai Keimanan dan Kemanusiaan Persaudaraan Cinta Tanah Air Indonesia." Teosofi: Jurnal Tasawuf dan Pemikiran Islam 7, no. 1 (June 5, 2017): 249–72. http://dx.doi.org/10.15642/teosofi.2017.7.1.249-272.

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The existence of the PCTA-I (Persaudaraan Cinta Tanah Air-Indonesia/Brotherhood for the Love of Indonesia Homeland) plays a pivotal role, especially for underprivileged people regardless of their religion and faith, tribe, and race. This organization has been, therefore, undeniably desirable to help the Indonesian society overcome their social problems. Focusing its discussion on the PCTA-I, this article seeks to answer such questions as how this organization has been initiated; what does it do to help overcome national problems, and what are the obstacles it faces in implementing the programs and how does it overcome such obstacles? A number of leaders and members of the PCTA-I Central Board have been interviewed. The murshid of the Tarekat Ṣiddīqīyah has been among the main informants of this study. Employing qualitative approach by focusing on interview, questionnaire, and documentation as the sources of data, the study indicates that the PCTA-I has been able to efficiently implement its programs due to solid participation and robust support of its voluntary community. Through its programs, the PCTA-I attempts to build what so-called “the soul of society” in order to achieve civilized and enlightened future of Indonesia.

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Cottingham, John DeWitte, William Bassett, and George Melendez. "Aircraft DC Power Quality Characteristics of a PCTRU." SAE International Journal of Aerospace 1, no. 1 (November 11, 2008): 1000–1006. http://dx.doi.org/10.4271/2008-01-2890.

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Sandu, Kishore. "Pediatric Laryngotracheal Stenosis: Where Are We Heading." Otolaryngology–Head and Neck Surgery 139, no. 2_suppl (August 2008): P67. http://dx.doi.org/10.1016/j.otohns.2008.05.215.

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Objective We compare decannulation rates after Laryngotracheal Reconstruction(LTR) and Cricotracheal Resection(CTR) in matched patients. Glottic Stenosis remains a challenge and can be treated by Extended Partial Cricotracheal Resection(PCTR). The objective of the paper is to systematically classify patients to be treated by these different techniques. Methods In 61% of patients, single-stage PCTR with peroperative resection of the tracheostoma was chosen if no more than 5 tracheal rings were resected with the SGS. If the location of the tracheostoma requires the resection of 6 or more tracheal rings, then PCTR was performed in 2 stages. 13% of children in this group sustained an anastomotic dehiscence, compared to 4.5% of children who had a shorter tracheal resection. 17 patients who weighed under 10 kg of body weight and were less than 1 year old underwent CTR and have all been decannulated. Results It is noteworthy that more than a single procedure was necessary in 68% of the cases to reach the aforementioned results with LTRs, whereas only 18% of the cases needed a second open procedure to achieve decannulation with PCTR. Extended PCTR with LT mold for complex frozen larynges has proven to have promise. Complications included anastomotic granulations, minor dehiscence. No patient had a recurrent laryngeal nerve palsy. Conclusions LTR is a less extensive procedure and is preferred for some grade II and less severe grade III stenoses. CTR is reserved for severe grade III and IV stenosis. Stenosis close to the vocal cords remains a challenge and can be treated by extended PCTR.

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Borkar, Hemant, and Mihriban Pekguleryuz. "Effect of Extrusion Parameters on Texture and Microstructure Evolution of Extruded Mg-1 pctMn and Mg-1 pctMn-Sr Alloys." Metallurgical and Materials Transactions A 46, no. 1 (November 4, 2014): 488–95. http://dx.doi.org/10.1007/s11661-014-2636-z.

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46

Iwata, Atsushi, Mohamed Mahdi Alshahni, Yayoi Nishiyama, Koichi Makimura, Shigeru Abe, and Tsuyoshi Yamada. "Development of a Tightly Regulatable Copper-Mediated Gene Switch System in Dermatophytes." Applied and Environmental Microbiology 78, no. 15 (May 18, 2012): 5204–11. http://dx.doi.org/10.1128/aem.00464-12.

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ABSTRACTTargeted gene deletion is now available for molecular genetic research of dermatophytes, and the physiological roles of several genes have been elucidated. However, this method cannot be applied to essential genes, which can be potential drug targets. To overcome this limitation, we have developed a conditional gene knockdown system using a copper-responsive promoter. The promoter sequence of the copper transporter geneCTR4(PCTR4) and that of the copper efflux pump geneCRP1(PCRP1) derived fromTrichophyton rubrumwere examined for their response to copper inArthroderma vanbreuseghemii. PCTR4was demonstrated to repress expression of a reporter gene in the presence of copper, while the activity of PCRP1was induced by addition of copper. Importantly, PCTR4regulated the gene expression more tightly. Furthermore, when PCTR4was applied to regulate the expression of the endogenous genesERG1andTRP5, their conditional mutants exhibited decreased growth activity under the repressive conditions. These results suggest that the PCTR4-based gene regulation system represents a powerful tool for identification and characterization of a broad range of genes, including essential genes, in dermatophytes.

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Hangai, Yoshihiko, Yuta Yamamoto, Yu Goto, Kenji Okada, and Nobuhiro Yoshikawa. "Friction Welding of Polycarbonate Plate and Aluminum Foam Fabricated by Precursor Foaming Process." Metals 13, no. 8 (July 29, 2023): 1366. http://dx.doi.org/10.3390/met13081366.

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Aluminum foam is expected to be one of the candidates for lightweight materials for structural components as it is lightweight and has excellent shock absorption and sound absorption properties. However, aluminum foam has low tensile and flexural strength due to its thin cell walls. Therefore, aluminum foam is used by combining with dense materials. In particular, with the recent trend toward multi-materials, research on the combination with lightweight resins is expected. In this study, we attempted to join aluminum foam fabricated by the precursor method to a thermoplastic resin polycarbonate (PCTA) plate by friction welding. It was found that the aluminum foam and PCTA plate can be joined in about 1 min by friction welding, by rotating the aluminum foam at 2000 rpm and pressing 1 mm into the PCTA plate. In addition, in the friction welding of aluminum foam and PCTA plate, it was found that the pores of the aluminum foam were maintained without being collapsed. The anchoring effect is presumably caused by the penetration of PCTA softened by the frictional heat generated by the friction welding into the pores. Furthermore, tensile tests of the joined samples showed that fracture occurred either at the joining interface or at the base material of the aluminum foam, and that the joining strength was equivalent to the tensile strength of the aluminum foam itself.

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Weisenberg, Elliot. "Pocket Companion to Robbins Pathologic Basis of Disease." Archives of Pathology & Laboratory Medicine 124, no. 10 (October 1, 2000): 1566. http://dx.doi.org/10.5858/2000-124-1566b-pctrpb.

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Sansbury, Brian E., Xiaofeng Li, Blenda Wong, Colin O. Riley, Ashley E. Shay, Robert Nshimiyimana, Nicos A. Petasis, Charles N. Serhan, and Matthew Spite. "PCTR1 Enhances Repair and Bacterial Clearance in Skin Wounds." American Journal of Pathology 191, no. 6 (June 2021): 1049–63. http://dx.doi.org/10.1016/j.ajpath.2021.02.015.

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Strobel, Laura, Kilian Vomstein, Christiana Kyvelidou, Susanne Hofer-Tollinger, Katharina Feil, Ruben-Jeremias Kuon, Susanne Ebner, Jakob Troppmair, and Bettina Toth. "Different Background: Natural Killer Cell Profiles in Secondary versus Primary Recurrent Pregnancy Loss." Journal of Clinical Medicine 10, no. 2 (January 7, 2021): 194. http://dx.doi.org/10.3390/jcm10020194.

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(1) Background: Prior studies suggested a significant impact of previous live births on peripheral natural killer cells (pNK) in patients with recurrent pregnancy loss (RPL). Patients with primary RPL (pRPL, no live birth) showed higher numbers of pNK than secondary RPL patients (sRPL, ≥ 1 live birth). (2) Methods: To further determine immunological differences between RPL patients and controls, we analysed pNK subpopulations and activation markers in pRPL (n = 47), sRPL (n = 24) and controls with previous live birth (sCtrl, n = 25) and nullipara (pCtrl, n = 60) within a prospective study. Percentages and numbers of CD56dimCD16bright cells, subpopulations and activation markers (CD57+, CD62L+, NKG2D+, NKp46+) were measured in non-pregnant RPL patients and n = 85 controls (n = 60 pCtrl, n = 25 sCtrl) in the mid-luteal phase by flow cytometry. (3) Results: Compared to sRPL patients, sCtrls showed higher CD56+ and CD56dimCD16bright numbers. Further, sRPL patients showed lower numbers of CD56dimCD16brightNKG2D+ and CD56dimCD16brightNKp46+ than sCtrls. (4) Conclusion: We suggest a chronic immune stimulation leading to a lower NK-cell count in sRPL patients with a lower NK cytotoxicity. This underlines the necessity to investigate pNK subpopulations as well as pRPL and sRPL separately to delineate the immune alterations in RPL.

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