Cross-section measurements of the (n,2n) and (n,p) reactions on 124,126,128,130,131,132Xe in the 14 MeV region and theoretical calculations of their excitation functions

The reaction cross-sections of 124Xe(n, 2n)123Xe, 126Xe(n, 2n)125Xe, 128Xe(n, 2n)127Xe, 130Xe(n, 2n)129mXe, 132Xe(n, 2n)131mXe, 130Xe(n, p)130I, 131Xe(n, p)131I, and 132Xe(n, p)132I were measured at the 13.5, 13.8, 14.1, 14.4, and 14.8 MeV neutron energies. The monoenergetic neutrons were generated through the 3H(d,n)4He reaction at the China Academy of Engineering Physics using the K-400 Neutron Generator with a solid 3H-Ti target. A high-purity germanium detector was used to measure the activities of the product. The reactions 93Nb(n, 2n)92mNb and 27Al(n, α)24Na served for neutron flux calibration. The cross sections of the (n,2n) and (n,p) reactions of the xenon isotopes were acquired within the 13–15 MeV neutron energy range. These cross-sections were then compared with the IAEA-exchange format (EXFOR) database-derived experimental data together with the evaluation results of the CENDL-3, ENDF/B-VIII.0, JENDL-4.0, RUSFOND, and JEFF-3.3 data libraries as well as the theoretical excitation function obtained using the TALYS-1.95 code. The cross-sections of the reactions (except for the 124Xe(n, 2n)123Xe and 132Xe(n, p)132I) at 13.5, 13.8, and 14.1 MeV are reported for the first time in this work. The present results are helpful to provide better cross-section constraints for these reactions in the 13–15 MeV region, thus improving the quality of the corresponding database. Meanwhile, these data can also be used for the verification of relevant nuclear reaction model parameters.

Analysis of Vaccine Supply and Demand in National Immunization Program for Children and the need for Establishing Vaccine Stockpiles in China

Introduction The number of vaccines used in China's childhood immunization program had continued to increase, from four in 1978 to ten in 2019. We described the supply and demand of vaccines, and compared the ratio of vaccine supply and demand of each vaccine to illustrate the shortage of vaccines and the need of vaccine stockpiles in China. Methods We downloaded the manufacturers supplying vaccines and the vaccination requirements for the national immunization program for children from 2016 to 2019 in the National Immunization Program Information system, as well as the batch issue data of biological products from the official website of China Academy of Food and Drug Control (CFDA). Vaccine prices were obtained from Chinese Central Government Procurement (CCGP).The demand, supply, and the ratio of vaccine supply and demand of each vaccine were calculated respectively. Results On average, five out of ten vaccines were supplied by three or more enterprises, three kinds of vaccines were supplied by two enterprises and two kinds of vaccines were supplied only by one enterprise between 2016 to 2019. The ratio of vaccine supply and demand of Diphtheria-tetanus and Group A meningitis polysaccharide were 79.52% and 67.99% respectively, with a potential shortage. There were three vaccines with a supply-demand ratio below 80% in 2016–2018, and five in 2019. The number of potential vaccine shortage was increasing. The average price of vaccines with potential shortage was $ 0.28. The average price of other vaccines without shortage was $ 1.8. Conclusions Most vaccines used in the childhood immunization program are available to meet demand, but there are also some vaccines with the risk of shortage and the number of vaccines with the risk of shortage tends to increase. The next step is to develop a national stockpiling mechanism to avoid a shortage of vaccines.

Arsenic Dispensing Powder Promotes Erythropoiesis in Myelodysplastic Syndromes via Downregulation of HIF1A and Upregulation of GATA Factors

Traditional Chinese Medicine (TCM) is a practical medicine based on thousands of years of medical practice in China. Arsenic dispensing powder (ADP) has been used as a treatment for MDS patients with a superior efficacy on anemia at Xiyuan Hospital of China Academy of Chinese Medical Sciences. In this study, we retrospectively analyzed MDS patients that received ADP treatment in the past 9 years and confirmed that ADP improves patients’ anemia and prolongs overall survival in intermediate-risk MDS patients. Then, we used the MDS transgenic mice model and cell line to explore the drug mechanism. In normal and MDS cells, ADP does not show cellular toxicity but promotes differentiation. In mouse MDS models, we observed that ADP showed significant efficacy on promoting erythropoiesis. In the BFU-E and CFU-E assays, ADP could promote erythropoiesis not only in normal clones but also in MDS clones. Mechanistically, we found that ADP could downregulate HIF1A in MDS clones through upregulation of VHL, P53 and MDM2, which is involved in two parallel pathways to downregulate HIF1A. We also confirmed that ADP upregulates GATA factors in normal clones. Thus, our clinical and experimental studies indicate that ADP is a promising drug to promote erythropoiesis in both MDS and normal clones with a superior outcome than current regular therapies. ADP promotes erythropoiesis in myelodysplastic syndromes via downregulation of HIF1A and upregulation of GATA factors.

“Spacecraft Thermal Control Technologies”

Into my hands came an exciting new book about space. “Spacecraft Thermal Control Technologies” is written by Professor Jianyin Miao, Qi Zhong, Professor Qiwei Zhao and Professor Xin Zhao. All the authors of this book are part of the Institute of Spacecraft System Engineering, China Academy of Space Technology (CAST), Beijing, China. Jianyin Miao is a head scientist of heat pipes at CAST and a Massachusetts Institute of Technology (MIT, USA) visiting professor, and is an academic leader for space thermal control technology at China Aerospace Science. Qi Zhong is a research fellow at CAST and his expertise is in the field of aerospace thermal control. Qiwei Zhao is a professor at CAST with expertise in the field of space thermophysics. Professor Xin Zhao has served as a chief designer of thermal control subsystems. He serves on the professional committee at CAST. He has received several national and ministerial awards for his work in this field. The series editor Peijian Ye, (China Academy of Space Technology, Beijing, China) is a Chinese aerospace engineer. He is a professor at the Beijing University of Aeronautics and Astronautics, China, and is a professor at the Harbin Institute of Technology, China. He is a research fellow and chief engineer at CAST. He is also the Chief Commander and Chief Designer of the Chinese Lunar Exploration Program. In his honour the inner main-belt asteroid 456677 Yepeijian, discovered by the Purple Mountain Observatory Near-Earth Object Survey Program at the XuYi Station, China, took his name in 2007.

Shrinkage Properties of Self-Compacting Rubber Lightweight Aggregate Concrete: Experimental and Analytical Studies

The shrinkage properties of self-compacting rubber lightweight aggregate concrete (SCRLC) were investigated by experimental and analytical studies in this paper. Rubber particles were used to substitute the sand in SCRLC by volume and rubber particles substitution percentages were 10%, 20%, 30%, 40% and 50%. The experimental results showed that the shrinkage strains of SCRLC increased with an increase of rubber particles substitution percentage. On the basis of China Academy of Building Research model and experimental data, a predictive model for describing the shrinkage strains of SCRLC was established. After analytical study, it was revealed that rubber particles substitution percentage of 80% in SCRLC might be the upper limit of substitution percentage; if the rubber particles substitution percentage was larger than 80%, the shrinkage strains of SCRLC would exceed the limiting value stipulated in JGJ51-2002 and the durability of SCRLC would drop to a worse status.

Assimilating Satellite Land Surface States Data from Fengyun-4A

Fengyun-4A is the new generation of Chinese geostationary meteorological satellites. Land surface albedo, land surface emissivity and land surface temperature are key states for land surface modelling. In this paper, the land surface albedo, land surface emissivity and land surface temperature data from Fengyun-4A were assimilated into the Integrated Urban land Model. The Fengyun-4A data are one of the data sources for the land data assimilation system which devoted to produce the high spatial and temporal resolution, multiple parameters near real-time land data sets. The Moderate-Resolution Imaging Spectroradiometer (MODIS) LSA and LSE data, the Institute of Atmospheric Physics, China Academy of Sciences (IAP) 325 m tower observation data and the observed 5 cm and 10 cm soil temperature data in more than 100 sites are used for validation. The results indicate the MODIS land surface albedo is much smaller than the Fengyun-4A and is superior to the Fengyun-4A for the Institute of Atmospheric Physics, China Academy of Sciences 325 m tower site. The Moderate-Resolution Imaging Spectroradiometer land surface emissivity is smaller than the Fengyun-4A in barren land surface and the differences is relatively small for other land use and land cover categories. In most regions of the research area, the Fengyun-4A land surface albedo and land surface emissivity are larger than those of the simulations. After the land surface albedo assimilation, in most regions the simulated net radiation was decreased. After the land surface emissivity assimilation, in most regions the simulated net radiation was increased. After the land surface temperature assimilation, the biases of the land surface temperature were decreased apparently; the biases of the daily average 5 cm and 10 cm soil temperature were decreased.

Álvaro Siza and Carlos Castanheira’s China Design Museum: Form, Contemporary City and Design Method

Portuguese architects, Álvaro Siza and Carlos Castanheira’s China Design Museum of the China Academy of Art in Hangzhou (2012-2018) calls for a problematization of the theme of the “boundary” at different levels. In this essay the project is compared with other relevant works in regards to form, the contemporary city and design method. Formed by two bars and a partly sunken volume enclosing a triangular courtyard, the building is immediately reminiscent of other L and U plans by Siza that question private/public and interior/exterior relationships. After Rem Koolhaas published “The Generic City” in 1994, the Chinese city became the epitome of the contemporary city. Since Siza’s architecture has been discussed in terms of its continuity with the city and tradition, the project of the China Design Museum raises the question: How does Siza work in the Chinese city? Siza and Castanheira’s building is at the same time part of a large campus planned by the well-known local architects Wang Shu and Lu Wenyu/Amateur Architecture, whose experimental approach to drawing and craft skills suggests yet another set of comparisons. To sum up, Siza and Castanheira avoid easy solutions: the siting and massing, scale, spatial organization and material expression of the China Design Museum provide a measure between realities – open/closed, traditional/contemporary, local/universal – that first appeared incommensurable.