Abstract: Objectives: This study aims to describe changes in hemodynamics and homeostasis after continuous renal replacement therapy (CRRT) in septic shock children without acute kidney injury. Methods: An observational study was conducted in the pediatric intensive care unit (PICU) at Vietnam National Children’s Hospital from January 2018 to June 2022. Children aged under 18 years old with septic shock and without acute kidney injury who required CRRT were analyzed on demographic factors, baseline clinical and laboratory results, changes in hemodynamics and homeostasis at 6 hours, 12 hours, 24 hours, 48 hours, 72 hours, 4 days and 5 days after CRRT initiation. Results: A total of 125 children (male, 57.6%) were enrolled in the study. The median age was 11.5 months (IQR: 5 – 29). Overall PICU mortality rate at day 28 was 40.8%. Among survivors, there was a statistically significant improvement in heart rate, mean blood pressure, vasoactive inotropic score (VIS), and pH at all mentioned periods after CRRT initiation. Lactatemia statistically significantly decreased after 24 hours of CRRT initiation (p 〈 0.05). Among non-survivors, there was a statistically significant improvement in heart rate at all the periods and in mean blood pressure at 6 hours and 12 hours, while there was no improvement in VIS, pH, and lactatemia. Conclusion: CRRT played an important role in stabilizing hemodynamics and homeostasis in septic shock children without acute kidney injury.        

Abstract: Abstract: In this study, the equations for estimating the number of tropical cyclones (TCs) at a 6-month lead-time in the Vietnam East Sea (VES) have been developed and tested. Three multivariate linear regression models in which regression coefficients were determined by different methods, including 1) method of least squares (MLR), 2) minimum absolute deviation method (LAD), 3) minimax method (LMV). The artificial neural network model (ANN) and some combinations of the above regression models were also used. The VES was divided into the northern region above 15ºN (VES_N15) and the southern one below that latitude (VES_S15). The number of TCs was calculated from the data of the Japan Regional Specialized Meteorological Center (RMSC) for the period 1981-2017. Principal components of the 14 climate indicators were selected as predictors. Results for the training period showed that the ANN model performed best in all 12 times of forecasts, following by the ANN-MLR combination. The poorest result was obtained with the LMV model. Results for the independent dataset showed that the number of adequate forecasts based on the MSSS scores decreased sharply compared to the training period and the models generated generally similar errors. The MLR model tended to give out the best results. Better-forecast results were obtained in the VES_N15 region followed by the VES and then the VES_S15 regions. Keywords: Tropical cyclone, Seasonal prediction, Vietnam East Sea (VES). References: [1] W. Landsea Christopher, Gerald D. Bell, William M. Gray, Stanley B. Goldenberg, The extremely active 1995 Atlantic hurricane season: Environmental conditions and verification of seasonal forecasts, Mon. Wea. Rev. 126 (1998) 1174-1193[2] W. Landsea Christopher, William M. Gray, Paul W. Mielke, Jr, Kenneth J. Berry, Seasonal Forecasting of Atlantic hurricane activity, Weather. 49 (1994) 273-284.[3] M. Gray William, Christopher W. Landsea, Paul W. 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Atmos. 120 (2015). doi:10.1002/2014JD022334.[18] Phan Van Tan, On the tropical cyclone activity in the Northwest Pacific basin and South China sea in relationship with ENSO, Journal of Science, Vietnam National University, Hanoi, t.XVIII, No1, (2002) 51-58. (In English)[19] Nguyễn Văn Tuyên, Xu hướng hoạt động của xoáy thuận nhiệt đới trên Tây Bắc Thái Bình Dương và biển Đông theo các cách phân loại khác nhau, Tạp chí KTTV. số 559 (2007) tr.4-10.[20] Đinh Bá Duy, Ngô Đức Thành; Phan Văn Tân, 2016, Mối quan hệ giữa ENSO và số lượng, cấp độ Xoáy thuận Nhiệt đới trên khu vực Tây Bắc - Thái Bình Dương, Biển Đông giai đoạn 1951-2015, VNU Journal of Science: Earth and Environmental Sciences, [S.l.], v. 32, n. 3S, sep. 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Tạp chí KTTV, số 571, tháng 7 năm 2008, tr.1-11.[27] Phan Văn Tân, 2009-2010, Nghiên cứu tác động của biến đổi khí hậu toàn cầu đến các yếu tố và hiện tượng khí hậu cực đoan ở Việt Nam, khả năng dự báo và giải pháp chiến lược ứng phó. Đề tài cấp Nhà nước, mã số KC08.29/06-10.[28] https://www.jma.go.jp/jma/jma-eng/jma-center/ rsmc-hp-pub-eg/besttrack.html. [29] https://www.esrl.noaa.gov/ psd/data/climateindices/ list/[30] T. Ngo-Duc, J. Matsumoto, H. Kamimera, and H.H. Bui, Monthly adjustment of Global Satellite Mapping of Precipitation (GSMaP) data over the VuGia–ThuBon River Basin in Central Vietnam using an artificial neural network. Hydrological Research Letters. 7(4), (2013) 85-90. doi:10.3178/hrl.7.85.[31] J. C. L. Chan, J. E. Shi and C. M. Lam, Seasonal forecasting of tropical cyclone activity over the Western North Pacific and the South China Sea, Wea. Forecasting. 13 (1998) 997-1004.[32] E. S. Blake, W. M. Gray, Prediction of August Atlantic Basin Hurricane Activity. Wea. 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Abstract: In this paper, we analyze an underlay two-way decode-and-forward scheme in which secondary relays use successive interference cancellation (SIC) technology to decode data of two secondary sources sequentially, and then generate a coded signal by superposition coding (SC) technology, denoted as SIC-SC protocol. The SIC-SC protocol is designed to operate in two time slots under effects from an interference constraint of a primary receiver and residual interference of imperfect SIC processes. Transmit powers provided to carry the data are allocated dynamically according to channel powers of interference and transmission, and a secondary relay is selected from considering strongest channel gain subject to increase in decoding capacity of the first data and decrease in collection time of channel state information. Closed-form outage probability expressions are derived from mathematical manipulations and verified by performing Monte Carlo simulations. An identical scheme of underlay two-way decodeand-forward relaying with random relay selection and fixed power allocations is considered to compare with the proposed SIC-SC protocol, denoted as RRS protocol. Simulation and analysis results show that the non-identical outage performances of the secondary sources in the proposed SIC-SC protocol are improved by increasing the number of the secondary relays and the interference constraint as well as decreasing the residual interference powers. Secondly, the performance of the nearer secondary source is worse than that of the farther secondary source. In addition, the proposed SIC-SC protocol outperforms the RRS comparison protocol, and effect of power allocations through channel powers is discovered. Finally, derived theory values are precise to simulation results. Keywords: Successive interference cancellation, superposition coding, power allocation, underlay cognitive radio, non-orthogonal multiple access, outage probability. 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