• Title/Summary/Keyword: Qi radiation

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An adaptive deviation-resistant neutron spectrum unfolding method based on transfer learning

  • Cao, Chenglong;Gan, Quan;Song, Jing;Yang, Qi;Hu, Liqin;Wang, Fang;Zhou, Tao
    • Nuclear Engineering and Technology
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    • v.52 no.11
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    • pp.2452-2459
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    • 2020
  • Neutron spectrum is essential to the safe operation of reactors. Traditional online neutron spectrum measurement methods still have room to improve accuracy for the application cases of wide energy range. From the application of artificial neural network (ANN) algorithm in spectrum unfolding, its accuracy is difficult to be improved for lacking of enough effective training data. In this paper, an adaptive deviation-resistant neutron spectrum unfolding method based on transfer learning was developed. The model of ANN was trained with thousands of neutron spectra generated with Monte Carlo transport calculation to construct a coarse-grained unfolded spectrum. In order to improve the accuracy of the unfolded spectrum, results of the previous ANN model combined with some specific eigenvalues of the current system were put into the dataset for training the deeper ANN model, and fine-grained unfolded spectrum could be achieved through the deeper ANN model. The method could realize accurate spectrum unfolding while maintaining universality, combined with detectors covering wide energy range, it could improve the accuracy of spectrum measurement methods for wide energy range. This method was verified with a fast neutron reactor BN-600. The mean square error (MSE), average relative deviation (ARD) and spectrum quality (Qs) were selected to evaluate the final results and they all demonstrated that the developed method was much more precise than traditional spectrum unfolding methods.

Dual-band Frequency Selective Surface Bandpass Filters in Terahertz Band

  • Qi, Limei;Li, Chao
    • Journal of the Optical Society of Korea
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    • v.19 no.6
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    • pp.673-678
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    • 2015
  • Terahertz dual-band frequency selective surface filters made by perforating two different rectangular holes in molybdenum have been designed, fabricated and measured. Physical mechanisms of the dual-band resonant responses are clarified by three differently configured filters and the electric field distribution diagrams. The design process is straightforward and simple according to the physical concept and some formulas. Due to the weak coupling between the two neighboring rectangle holes with different sizes in the unit cell, good dual-band frequency selectivity performance can be easily achieved both in the lower and higher bands by tuning dimensions of the two rectangular holes. Three samples are fabricated, and their dual-band characteristics have been demonstrated by a THz time-domain spectroscopy system. Different from most commonly used metal-dielectric structure or metal-dielectric-metal sandwiched filters, the designed dual-band filters have advantages of easy fabrication and low cost, the encouraging results afforded by these filters could find their applications in dual-band sensors, THz communication systems and other emerging THz technologies.

Efficacy and Toxicity of Anti-VEGF Agents in Patients with Castration-Resistant Prostate Cancer: a Meta-analysis of Prospective Clinical Studies

  • Qi, Wei-Xiang;Fu, Shen;Zhang, Qing;Guo, Xiao-Mao
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.19
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    • pp.8177-8182
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    • 2014
  • Background: Blocking angiogenesis by targeting vascular endothelial growth factor (VEGF) signaling pathway to inhibit tumor growth has proven to be successful in treating a variety of different metastatic tumor types, including kidney, colon, ovarian, and lung cancers, but its role in castration-resistant prostate cancer (CRPC) is still unknown. We here aimed to determine the efficacy and toxicities of anti-VEGF agents in patients with CRPC. Materials and Methods: The databases of PubMed, Web of Science and abstracts presented at the American Society of Clinical Oncology up to March 31, 2014 were searched for relevant articles. Pooled estimates of the objective response rate (ORR) and prostate-specific antigen (PSA) response rate (decline ${\geq}50%$) were calculated using the Comprehensive Meta-Analysis (version 2.2.064) software. Median weighted progression-free survival (PFS) and overall survival (OS) time for anti-VEGF monotherapy and anti-VEGF-based doublets were compared by two-sided Student's t test. Results: A total of 3,841 patients from 19 prospective studies (4 randomized controlled trials and 15 prospective nonrandomized cohort studies) were included for analysis. The pooled ORR was 12.4% with a higher response rate of 26.4% (95%CI, 13.6-44.9%) for anti-VEGF-based combinations vs. 6.7% (95%CI, 3.5-12.7%) for anti-VEGF alone (p=0.004). Similarly, the pooled PSA response rate was 32.4% with a higher PSA response rate of 52.8% (95%CI: 40.2-65.1%) for anti-VEGF-based combinations vs. 7.3% (95%CI, 3.6-14.2%) for anti-VEGF alone (p<0.001). Median PFS and OS were 6.9 and 22.1 months with weighted median PFS of 5.6 vs. 6.9 months (p<0.001) and weighted median OS of 13.1 vs. 22.1 months (p<0.001) for anti-VEGF monotherapy vs. anti-VEGF-based doublets. Conclusions: With available evidence, this pooled analysis indicates that anti-VEGF monotherapy has a modest effect in patients with CRPC, and clinical benefits gained from anti-VEGF-based doublets appear greater than anti-VEGF monotherapy.

Color Change of Major Wood Species Planted in Indonesia by Ultraviolet Radiation (자외선 조사에 의한 인도네시아 주요 조림수종 목재의 재색변화)

  • Park, Se-Hwi;Jang, Jae-Hyuk;Qi, Yue;Hidayat, Wahyu;Hwang, Won-Joong;Febrianto, Fauzi;Kim, Nam-Hun
    • Journal of the Korean Wood Science and Technology
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    • v.44 no.1
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    • pp.9-18
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    • 2016
  • This study was performed to understand wood durability to climate deterioration of planted Indonesian wood specie such as Albizia, Gmelina, Mangium and Mindi. Wood samples were exposed to indoor and outdoor condition. $L^*a^*b^*$ and Color changes (${\Delta}E*ab$) were determined by a spectrophotometer. As a result, color of all samples was changed more markedly by ultraviolet radiation. In indoor test with UV, brightness of wood specimens from four species was not changed and all samples were changed into more reddish and yellowish. In accelerated weathering test, all samples were bleached and changed into more greenish and blueish. In outdoor test, brightness of wood specimens decreased in Albizia and Gmelina and increased in Mangium and Mindi. All wood specimens in outdoor test were changed into more greenish and blueish. Albizia and Gmleina woods showed greater color change than those of Mangium and Mindi. Especially, color change of wood samples might be influenced greatly by moisture. In conclusion, wood color changed into more clearly by UV radiation. Therefore, exposing woods to UV radiation could be one of reasonable methods to improve wood quality on visual characteristic.

Novel and Effective Almagate Enema for Hemorrhagic Chronic Radiation Proctitis and Risk Factors for Fistula Development

  • Yuan, Zi-Xu;Ma, Teng-Hui;Zhong, Qing-Hua;Wang, Huai-Ming;Yu, Xi-Hu;Qin, Qi-Yuan;Chu, Li-Li;Wang, Lei;Wang, Jian-Ping
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.2
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    • pp.631-638
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    • 2016
  • Radiation proctitis is a common complication after radiotherapy for pelvic malignant tumors. This study was conducted to assess the efficacy of novel almagate enemas in hemorrhagic chronic radiation proctitis (CRP) and evaluate risk factors related to rectal deep ulcer or fistula secondary to CRP. All patients underwent a colonoscopy to confirm the diagnosis of CRP and symptoms were graded. Typical endoscopic and pathological images, risk factors, and quality of life were also recorded. A total of 59 patients were enrolled. Gynecological cancers composed 93.1% of the primary malignancies. Complete or obvious reduction of bleeding was observed in 90% (53/59) patients after almagate enema. The mean score of bleeding improved from 2.17 to 0.83 (P<0.001) after the enemas. The mean response time was 12 days. No adverse effects were found. Moreover, long-term successful rate in controlling bleeding was 69% and the quality of life was dramatically improved (P=0.001). The efficacy was equivalent to rectal sucralfate, but the almagate with its antacid properties acted more rapidly than sucralfate. Furthermore, we firstly found that moderate to severe anemia was the risk factor of CRP patients who developed rectal deep ulcer or fistulas (P= 0.015). We also found abnormal hyaline-like thick wall vessels, which revealed endarteritis obliterans and the fibrosis underlying this disease. These findings indicate that almagate enema is a novel effective, rapid and well-tolerated method for hemorrhagic CRP. Moderate to severe anemia is a risk factor for deep ulceration or fistula.

Analytical Prediction of Transmission Error and Load Distribution for a Plugin HEV (플러그인 HEV용 변속기전달오차와 하중분포에 관한 연구)

  • Zhang, Qi;Kang, Jae-Hwa;Yun, Gi-Baek;Lyu, Sung-Ki
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.11 no.3
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    • pp.116-121
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    • 2012
  • In recent years, world is faced with a transportation energy dilemma, and the transportation is dependent on a single fuel - petroleum. However, Hybrid Electric Vehicle(HEV) technology holds more advantages to reduce the demand for petroleum in the transportation by efficiency improvements of petroleum consumption. Therefore, there is a trend that lower gear noise levels are demanded in HEV for drivers to avoid annoyance and fatigue during operation. And meshing transmission error(T.E.) is the excitation that leads to the tonal noise known as gear whine, and radiated gear whine is also the dominant source of noise in the whole gearbox. This paper presents a method for the analysis of gear tooth profile and lead modification, and the predictions of transmission error and load distribution are shown under one loaded torque for the 1st gear pair of HEV gearbox. The test is also obtained before tooth micro-modification under the torque. At last, the appropriate tooth modification is used to minimize the transmission error and load distribution under the loaded torque. It is a good approach which the simulated result is used to improve the design in order to minimize the radiation gear whine noise.

Autophagy-associated Targeting Pathways of Natural Products during Cancer Treatment

  • Zhang, Shu-Fang;Wang, Xiao-Lu;Yang, Xiao-Qi;Chen, Ning
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.24
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    • pp.10557-10563
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    • 2015
  • It is well known that conventional chemotherapy and radiation therapy can result in toxicity to both normal cells and tumor cells, which causes limitations in the application of these therapeutic strategies for cancer control. Novel and effective therapeutic strategies for cancers with no or low toxicity for normal cells are a high priority. Therefore, natural products with anticancer activity have gained more and more attention due to their favorable safety and efficacy profiles. Pre-clinical and clinical studies have demonstrated that several representative natural compounds such as resveratrol, epigallocatechin-3-gallate, curcumin, allicin and ginsenosides have obvious anticancer potential. In this article, we summarize autophagy-associated targeting pathways of such natural products for inducing the death of cancer cells, and discuss the core autophagic pathways involved in cancer treatments. Recent advances in the discovery, evaluation and exploitation of natural compounds as therapeutic agents for cancers will provide references and support in pre-clinical and clinical application of novel natural drugs for the treatment of primary and metastatic tumors in the future.

Quality indicators for cervical cancer care in Japan

  • Watanabe, Tomone;Mikami, Mikio;Katabuchi, Hidetaka;Kato, Shingo;Kaneuchi, Masanori;Takahashi, Masahiro;Nakai, Hidekatsu;Nagase, Satoru;Niikura, Hitoshi;Mandai, Masaki;Hirashima, Yasuyuki;Yanai, Hiroyuki;Yamagami, Wataru;Kamitani, Satoru;Higashi, Takahiro
    • Journal of Gynecologic Oncology
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    • v.29 no.6
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    • pp.83.1-83.10
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    • 2018
  • Objective: We aimed to propose a set of quality indicators (QIs) based on the clinical guidelines for cervical cancer treatment published by The Japan Society of Gynecologic Oncology, and to assess adherence to standard-of-care as an index of the quality of care for cervical cancer in Japan. Methods: A panel of clinical experts devised the QIs using a modified Delphi method. Adherence to each QI was evaluated using data from a hospital-based cancer registry of patients diagnosed in 2013, and linked with insurance claims data, between October 1, 2012, and December 31, 2014. All patients who received first-line treatment at the participating facility were included. The QI scores were communicated to participating hospitals, and additional data about the reasons for non-adherence were collected. Results: In total, 297 hospitals participated, and the care provided to 15,163 cervical cancer patients was examined using 10 measurable QIs. The adherence rate ranged from 50.0% for 'cystoscope or proctoscope for stage IVA' to 98.8% for 'chemotherapy using platinum for stage IVB'. Despite the variation in care, hospitals reported clinically valid reasons for more than half of the non-adherent cases. Clinically valid reasons accounted for 75%, 90.9%, 73.4%, 44.5%, and 88.1% of presented non-adherent cases respectively. Conclusion: Our study revealed variations in pattern of care as well as an adherence to standards-of-care across Japan. Further assessment of the causes of variation and non-adherence can help identify areas where improvements are needed in patient care.

Growth and Differentiation Effects of Homer3 on a Leukemia Cell Line

  • Li, Zheng;Qiu, Hui-Ying;Jiao, Yang;Cen, Jian-Nong;Fu, Chun-Mei;Hu, Shao-Yan;Zhu, Ming-Qing;Wu, De-Pei;Qi, Xiao-Fei
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.4
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    • pp.2525-2528
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    • 2013
  • The Homer protein family, also known as the family of cytoplasmic scaffolding proteins, which include three subtypes (Homer1, Homer2, Homer3). Homer3 can regulate transcription and play a very important role in the differentiation and development for some tissues (e.g. muscle and nervous systems). The current studies showed that Homer3 abnormal expression changes in acute myeloid leukemia (AML). Forced expression of Homer3 in transfected K562 cells inhibited proliferation, influenced the cell cycle profile, affected apoptosis induced by $As_2O_3$ through inhibition of Bcl2 expression, and also promoted cell differentiation induced by 12-O-tetra decanoylphorbol-acetate (TPA). These results showed that Homer3 is a novel gene which plays a certain role in the occurrence and development of AML.

The novel gene LRP15 is regulated by DNA methylation and confers increased efficiency of DNA repair of ultraviolet-induced DNA damage

  • Xu, Zhou-Min;Gao, Wei-Ran;Mei, Qi;Chen, Jian;Lu, Jing
    • BMB Reports
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    • v.41 no.3
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    • pp.230-235
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    • 2008
  • LRP15 is a novel gene cloned from lymphocytic cells, and its function is still unknown. Bioinformatic data showed that LRP15 might be regulated by DNA methylation and had an important role in DNA repair. In this study, we investigate whether the expression of LRP15 is regulated by DNA methylation, and whether overexpression of LRP15 increases efficiency of DNA repair of UV-induced DNA damage in HeLa cells. The results showed (1) the promoter of LRP15 was hypermethylated in HeLa cells, resulting a silence of its expression. Gene expression was restored by a demethylating agent, 5-aza-2'-deoxycytidine, but not by a histone deacetylase inhibitor, trichostatin A; (2) overexpression of LRP15 inhibited HeLa cell proliferation, and the numbers of cells in the G2/M phase of the cell cycle in cells transfected with LRP15 increased about 10% compared with controls; (3) cyclin B1 level was much lower in cells overexpressing LRP15 than in control cells; and (4) after exposure to UV radiation, the LRP15-positive cells showed shorter comet tails compared with the LRP15-negative cells. From these results we conclude that the expression of LRP15 is controlled by methylation in its promoter in HeLa cells, and LRP15 confers resistance to UV damage and accelerates the DNA repair rate.