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Huibin Sun,Zhengxin Wu,Yugang Ma,Jinbin Lu,Guoqing Liu,Haige Zhao,Yin Wang,Yanqi Hu 한국물리학회 2019 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.75 No.9
The radiation environment in space poses signicant challenges to human health, and it is a ma- jor concern in long duration, manned space missions. Outside Earth's protective magnetosphere, astronauts are exposed to higher levels of galactic cosmic rays (GCRs), whose physical character- istics are distinct from those of terrestrial sources of radiation, such as X-rays and gamma-rays. GCRs include high-energy heavy ions, many of which have ranges that exceed the depth of shielding and can be launched in realistic scenarios. Protecting the astronauts from these particles has been a key issue in manned space missions. Therefore, a need exists for reliable simulations of these harmful effects for risk assessment and shielding optimization in manned space missions. The aim of this work was to investigate shielding materials that can be used in deep space and planetary exploration. In this work, we used the Geant4 radiation transport code, originally developed by the International Geant4 Collaboration, and we compared the radiation shielding effectivenesses of polyethylene, aluminum, water, and carbon ber targets hit by 1GeV/nucleon 56Fe (considered as a representative of high-energy GCR). In addition, the total absorbed doses at the water phantom behind these targets were calculated using the Geant4 simulation code. The calculated results were analyzed, compared, and discussed. The results show that polyethylene is the best space radiation shielding material for a given areal density, followed by water, carbon ber, and then aluminum.
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Weiyan Liu,Huiming Ji,Jian Wang,Xuerong Zheng,Junyun Lai,Junna Ji,Tongfei Li,Yuanliang Ma,Haiqin Li,Suqin Zhao,Zhengguo Jin 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2015 NANO Vol.10 No.3
"Uniform hexagonal covellite CuS thin films were deposited at room temperature by an in situ solution chemical reaction using copper precursor solid films as cationic source and ammonium sulfide ethanol solution as anionic reaction medium. We investigated the influence of both ethanolamine and butanol contents used in copper nitrate/ethylene glycol monomethylether (EGME) cationic solution for the preparation of copper precursor solid films, deposition cycle numbers and annealing treatment of the as-grown thin films by X-ray diffraction (XRD), FESEM, energy dispersive X-ray fluorescence EDX, transmission electron microscopy–Selected area electronic diffraction (TEM–SAED), atomic force microscopy (AFM) and ultraviolet-visible-near-infrared (UV-Vis–NIR) measurements. Photo-response of the CuS thin films was characterized by linear sweep voltammetry. The deposited CuS thin films were used to sensitize TiO2 anodes for solar cell application. The results showed that the CuS films had two-dimension oriented, half-sheet shaped growing morphology standing disorderly but vertically to substrates, and the calculated texture coefficient TC(102) verified that the half-sheet shaped crystallites had (102) plane orientation. This in situ multi-deposition process had an average deposited rate of 9 nm per cycle, and a selfperfect function to grow smooth, uniform and 2D oriented morphology with increase in the dip-cycle numbers. The photocurrent density was 14.5 Ma/cm2 at 1 V versus Ag/AgCl electrode for the annealed CuS thin films. CuS-sensitized TiO2 solar cells had a maximum conversion efficiency of 0.224%."
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Ma Chen,Liu Hui,Liu Bo,Zhao Ju-Peng,Zhao Qing-Ying,Song Zi-Jiao,Han Xin,Zhan Guo-Ping 한국응용곤충학회 2022 Journal of Asia-Pacific Entomology Vol.25 No.4
The cacao mealybug, Planococcus lilacinus Cock, is an important quarantine pest. Infested commodity should be subject to appropriate phytosanitary treatment, while irradiation is recommended for the cacao mealybug. Radio-tolerance comparison tests were conducted on the crawler, nymphs, and adult females of P. lilacinus at the X-ray radiation doses of 40, 80, and 120 Gy, respectively. The results showed that irradiation had a strong effect on preventing of development and reproduction; the adult female stage was identified as the most tolerant. During the following dose–response tests, among young and late females X-ray-irradiation (20–100 Gy), the late females were most tolerant when preventing F 1 generation 2nd instars emergence was used as the evaluation criterion. Minimum absorbed dose and its 95 % fiducial limits to provide probit 9 efficacy at 95 % confidence level (100 % mortality/inhibition in an estimated population of 93,616 individuals) were 131.5 Gy (122.5, 142.6 Gy) and 144.4 Gy (132.7, 159.4 Gy), estimating from the probit analysis on dose-mortality data of 1–30 and 1–10-day-old neonates laid by late females, respectively. In the large-scale confirmatory tests, a total of estimating 97,384 late females of P. lilacinus rearing on the pumpkins fruits were irradiated with gamma-ray at the target dose of 135 or 145 Gy (measured doses 126.1–163.0 Gy), which resulted in no F 1 generation 2nd nymphs developing during a 6-week post-treatment period. The treatment efficacy calculated is 99.9969 % at the 95 % confidence level. Therefore, a minimum absorbed dose of 163.0 Gy is recommended for phytosanitary treatment of P. lilacinus in infested commodity.
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Zhao Ma 고려대학교 민족문화연구원 2017 Cross-Currents Vol.- No.22
From October 1950 to July 1953, the nascent Chinese state entered into a strategic alliance with North Korea; hundreds of thousands of Chinese soldiers shed blood on the Korean peninsula in defense of the socialist homeland and advancing Communist internationalism. But since the end of the Korean War, China has moved from revolutionary idealism and political radicalism in Mao’s era to the current post-socialist pragmatism and materialism. As the ideological winds shift, China’s contemporary propaganda apparatus must redefine the Korean War in order to reconcile the complexity of the war and wartime alliance with contemporary political concerns and popular views. By focusing on a documentary film, The Unforgettable Victory, produced by China’s leading state-run film studio in 2013, this article explores the ways in which the official media of the post-socialist era presents the past revolutionary war. The new film celebrates the splendid valor of Chinese soldiers, civilians’ heroic sacrifices, and the war’s nationalist legacy; however, it purposefully forgets the revolutionary fervor and internationalist sentiments that once forged the Sino–North Korean alliance and empowered wartime mobilization. This article examines the process of remembering and forgetting, and reveals government propaganda’s latest efforts to demobilize contemporary viewers while infusing the past revolutionary war with ideological clarity and political certainty in post-socialist China.
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Zhao, Xueyan,Yang, Qiang,Zhao, Kewei,Jiang, Chao,Ren, Dongren,Xu, Pan,He, Xiaofang,Liao, Rongrong,Jiang, Kai,Ma, Junwu,Xiao, Shijun,Ren, Jun,Xing, Yuyun Asian Australasian Association of Animal Productio 2016 Animal Bioscience Vol.29 No.7
In the last few decades, transgenic animal technology has witnessed an increasingly wide application in animal breeding. Reproductive traits are economically important to the pig industry. It has been shown that the bone morphogenetic protein receptor type IB (BMPR1B) A746G polymorphism is responsible for the fertility in sheep. However, this causal mutation exits exclusively in sheep and goat. In this study, we attempted to create transgenic pigs by introducing this mutation with the aim to improve reproductive traits in pigs. We successfully constructed a vector containing porcine BMPR1B coding sequence (CDS) with the mutant G allele of A746G mutation. In total, we obtained 24 cloned male piglets using handmade cloning (HMC) technique, and 12 individuals survived till maturation. A set of polymerase chain reactions indicated that 11 of 12 matured boars were transgene-positive individuals, and that the transgenic vector was most likely disrupted during cloning. Of 11 positive pigs, one (No. 11) lost a part of the terminator region but had the intact promoter and the CDS regions. cDNA sequencing showed that the introduced allele (746G) was expressed in multiple tissues of transgene-positive offspring of No.11. Western blot analysis revealed that BMPR1B protein expression in multiple tissues of transgene-positive $F_1$ piglets was 0.5 to 2-fold higher than that in the transgene-negative siblings. The No. 11 boar showed normal litter size performance as normal pigs from the same breed. Transgene-positive $F_1$ boars produced by No. 11 had higher semen volume, sperm concentration and total sperm per ejaculate than the negative siblings, although the differences did not reached statistical significance. Transgene-positive $F_1$ sows had similar litter size performance to the negative siblings, and more data are needed to adequately assess the litter size performance. In conclusion, we obtained 24 cloned transgenic pigs with the modified porcine BMPR1B CDS using HMC. cDNA sequencing and western blot indicated that the exogenous BMPR1B CDS was successfully expressed in host pigs. The transgenic pigs showed normal litter size performance. However, no significant differences in litter size were found between transgene-positive and negative sows. Our study provides new insight into producing cloned transgenic livestock related to reproductive traits.
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Diagnostic Accuracy of 18F-FDG-PET in Patients with Testicular Cancer: a Meta-analysis
Zhao, Jing-Yi,Ma, Xue-Lei,Li, Yan-Yan,Zhang, Bing-Lan,Li, Min-Min,Ma, Xue-Lei,Liu, Lei Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.8
Objective: Fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) is a new technique for identifying different malignant tumors using different uptake values between tumor cells and normal tissues. Here we assessed the diagnostic accuracy of 18F-FDG-PET in patients with testicular cancer by pooling data of existing trials in a meta-analysis. Methods: PubMed/MEDLINE, Embase and Cochrane Central Trials databases were searched and studies published in English relating to the diagnostic value of FDG-PET for testicular cancer were collected. The summary receiver operating characteristic (SROC) curve was used to examine the FDG-PET accuracy. Results: A total of 16 studies which included 957 examinations in 807 patients (median age, 31.1 years) were analyzed. A meta-analysis was performed to combine the sensitivity and specificity and their 95% confidence intervals (CIs), from diagnostic odds ratio (DOR), positive likelihood ratios (PLR), negative likelihood ratio (NLR). SROC were derived to demonstrate the diagnostic accuracy of FDG-PET for testicular cancer. The pooled sensitivity and specificity were 0.75 (95% confidence interval (CI), 0.70-0.80) and 0.87 (95% CI, 0.84-0.89), respectively. The pooled DOR was 35.6 (95% CI, 12.9-98.3). The area under the curve (AUC) was 0.88. The pooled PLR and pooled NLR were 7.80 (95% CI, 3.73-16.3) and 0.31 (95% CI, 0.23-0.43), respectively. Conclusion: In patients with testicular cancer, 18F-FDG-PET demonstrated a high SROC area, and could be a potentially useful tool if combined with other imaging methods such as MRI and CT. Nevertheless, the literature focusing on the use of 18F-FDG-PET in this setting still remains limited.
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Simulation and Optimization Study on Layout Planning of Plant Factory Based on WITNESS
Li Ma,Meiqiong Ma,Chao Ma,Jingwen Deng,Xingluo Liu,Lijun Zhao 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.5
The emergence of plant factory has solved great restriction problem of natural environment in the traditional agriculture. Therefore, it has been the research concentrate on the facility agriculture in recent years. However, the reasonability of factory's production process and layout determines quality of the product, production efficiency and economic benefits. This paper took Wuchang Jingtian Plant Factory as an example, analyzed the production process and layout and provided a corresponding improvement scheme which was verified by the WITNESS simulation software. An optimal solution was determined from the evaluation index of production efficiency, busy rate, production cycle etc.. Besides, the simulation analysis of production cost before and after the improvement verified the improved plant factory operation is effective and feasible. This improvement scheme not only improved efficiency of production system of the plant factory, but also reduced the operating cost.
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Rui Ma,Chao Ma,Ruixue Zhai,Jun Zhao 한국정밀공학회 2022 International Journal of Precision Engineering and Vol.23 No.5
The springback control method is usually based on surface compensation to make the shape of the springback consistent with the target. At present, it is mainly realized by theoretical calculation or numerical simulation, but the difference between material model and theoretical model leads to unstable compensation accuracy. In this paper, a compensation mechanism which based on the iterative principle of implicit equation is proposed from the point of view of mathematical analysis. The final shape of the part converges to the target shape by means of finite compensation with the iterative method. In this paper, the iterative compensation mechanism is applied to the free bending and stretch-bending processes under plane stress state, and the uniform curvature and variable curvature are compensated iteratively. The next iteration compensation profile is predicted according to the convergence of the iterative principle. Experimental results show that the iterative compensation method can predict the next compensation value, and the error is less than the target value after 2–3 iterations. The error convergence of the method studied in this project is directional and the convergence speed is fast. The compensation value can be quantitatively predicted, which has theoretical significance and application value for engineering design, mold repair and numerical simulation.
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