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radiation resistance property of barium gallo-germanate glass doped by Nb_(2)O_(5)

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Chinese Physics B 2022年第2期31卷 593-597页

作者：刘桂榕陈晓东刘红刚王琰孙敏闫娜钱奇杨中民 State Key Laboratory of Luminescent Materials and Devices and Institute of Optical Communication Materials South China University of TechnologyGuangzhou 510640China Guangdong Planning and Designing Institute of Telecommunications Co.LTD Guangzhou 510630China Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques South China University of TechnologyGuangzhou 510640China Qingyuan Csg New Energy-Saving Materials Co. LTDQingyuan 511650China

Effects of Nb_(2)O_(5)dopant on the radiation response of barium gallo-germanate(BGG)glass are studied mainly by electron paramagnetic resonance and absorption spectroscopy.Owing to the Nb^(5+)$Nb^(3+)interconversion in doped samples,formations of Ge-related non-bridging oxygen hole center and Ge-related electron center defects after g-ray irradiation are inhibited.Thereby,Nb_(2)O_(5)dopant can enhance radiation resistance of BGG glass,and 1.0%Nb2O5 concentration is the best.

关键词： germanate glass radiation resistance Nb2O5 dopant

MiR-21 Mediates the radiation resistance of Glioblastoma Cells by Regulating PDCD4 and hMSH2

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2013年第4期33卷 525-529页

作者：晁腾飞熊慧华刘巍陈阳张佳璇 Cancer Centre Tongji HospitalTongji Medical CollegeHuazhong University of Science and Technology Department of Neurosurgery Beijing Tiantan HospitalCapital Medical University MOE Key Laboratory of Bioinformatics Bioinformatics Division/Center for Synthetic & Systems BiologyTNLISTTsinghua University Department of Radiology Tongji HospitalTongji Medical CollegeHuazhong University of Science and Technology

Summary： The purpose of this study was to investigate the molecular mechanism by which miR-21 and its target genes mediate radiation resistance of glioblastoma cells. Real-time PCR was employed to detect miR-21 expression in normal brain tissues, glioblastoma tissues and glioblastoma cell lines （A172, T98G and U87MG）. T98G cells were transfected with anti-miR-21 oligonucleotides, or plasmids con- taining PDCD4 or hMSH2 （PDCD4-pcDNA3 and hMSH2-pcDNA3）. The survival curve was obtained to investigate the sensitivity of T98G cells to radiation. Cell apoptosis was measured by using the Cas- pase-3/7 kit and cell cycle by flow cytometry. Western blotting was performed to detect the expression of hMSH2 and PDCD4 in miR-21-inhibiting T98G cells. The results showed that miR-21 expression in glioblastoma cells and tissues was conversely associated with the radiation sensitivity. Over-expression of miR-21 resulted in radiation resistance, while knockdown of miR-21 led to higher sensitivity of glioblastma cells to radiation. After miR-21 knockdown, the apoptosis of T98G cells was significantly increased and the G2 phase arrest was more significant. In addition, miR-21 knockdown increased the expression of endogenous PDCD4 and hMSH2, which contributed to the apoptosis and G2 arrest of T98G cells. The findings suggested that miR-21 may mediate the resistance of glioblastoma cells against radiation via its target genes PDCD4 and hMSH2. MiR-21 and its target genes may be used as potential molecular targets for clinical radiotherapy sensitization in the future.

关键词： microRNA glioblastoma radiation resistance apoptosis cell cycle

Latest developments in room-temperature semiconductor neutron detectors: Prospects and challenges

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Science China(Physics,Mechanics & Astronomy) 2023年第3期66卷 11-31页

作者： Linyue Liu Xiao Ouyang Runlong Gao Pengying Wan Xiaoping Ouyang State Key Laboratory of Intense Pulsed radiation Simulation and Effect Northwest Institute of Nuclear TechnologyXi’an 710024China Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China School of Microelectronics Xi’an Jiaotong UniversityXi’an 710049China

Semiconductor-based neutron-detectors are characterized by small size, high energy-resolution, good spatial resolution, and stable response(at the depletion voltage). Consequently, these neutron-detectors are important for the fields of nuclear proliferation prevention, oil exploration, monitoring neutron-scattering experiments, cancer treatments, and space radiation effect research. However, there are some well-known problems for conventional silicon-based neutron detectors: low neutron-detection efficiency and limited resistance to radiation. Therefore, critical improvements are needed to enable sufficiently effective and practical neutron detection. To address these problems, direct-conversion neutron detectors as well as wide bandgap semiconductor-based detectors have been developed and studied intensely during the past years. Significant progress with respect to detection efficiency, radiation resistance, and room temperature operation was achieved. This paper reviews the latest research highlights, remaining challenges, and emerging technologies of direct-conversion neutron detectors as well as wide-bandgap semiconductor neutron detectors. This compact review serves as a reference for researchers interested in the design and development of improved neutron detectors in the future.

关键词： fusion reaction neutron convertor neutron detectors wide bandgap semiconductor detection efficiency radiation resistance

Charged particles:Unique tools to study irradiation resistance of concentrated solid solution alloys

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Journal of Materials Science & Technology 2023年第9期140卷 260-276页

作者： Yanwen Zhang Lumin Wang William J.Weber Materials Science and Technology Division Oak Ridge National LaboratoryOak RidgeTN37831USA Department of Materials Science&Engineering University of TennesseeKnoxvilleTN37996USA Department of Nuclear Engineering and Radiological Sciences University of MichiganAnn ArborMI48109USA

Many multicomponent concentrated solid solution alloys(CSAs),including high-entropy alloys(HEAs),exhibit improved radiation resistance and enhanced structural stability in harsh environments.To study and assess irradiation resistance of nuclear materials,energetic ion and electron beams are commonly used to create displacement damage.Moreover,charged particles of ions,electrons,and positrons are unique tools to create and characterize radiation effects.Ion beam analysis(e.g.,Rutherford backscattering spectrometry,nuclear reaction analysis,and time-of-flight elastic recoil detection analysis),electron microscopy techniques(e.g.,transmission or scanning electron microscopy,and electron diffraction),and positron annihilation spectroscopy have been applied to characterize irradiated CSAs or HEAs to understand defect formation and evolution together with chemical and microstructural information.Their distinctive analyzing power and some perspectives in these techniques are reviewed.In developing structural alloys desirable for applications in advanced reactors,neutron exposure is a critical test but the limitation in achievable high damage levels is,however,a bottleneck.Ion irradiation is often used as a surrogate for neutron irradiation,and the associated reduced transmutations and higher displacements per atom(dpa)rates are desirable for materials research.Nevertheless,cautions need to be taken when relying on ion irradiation results for reactor evaluations.Literature on differences between ions and neutrons is briefly reviewed.In addition,the links to bridge the current advances on fundamental understandings to reactor applications are discussed to lay the groundwork between neutrons and ions for radiation effects studies.

关键词： chemical disorder high-entropy alloys chemically complex alloys charged particles radiation resistance displacement damage electronic energy loss and ionization transmutation

Flexible, high sensitive and radiation-resistant pressure-sensing hydrogel

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Chinese Chemical Letters 2022年第2期33卷 1011-1016页

作者： Zhiwen Jiang Yusong Wang Guoqing Xu Zhuoni Jiang Zhiqing Ge Mozhen Wang Xuewu Ge CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China

Excellent radiation resistance is a prerequisite for pressure-sensitive hydrogels to be used in high-energy radiation environments. In this work, tannic acid-modified boron nitride nanosheet(BNNS-TA) is first prepared as the radiation-resistant additive by a facile one-step ball milling of hexagonal boron nitride and tannic acid. Then, polyacrylamide(PAAm)-based pressure-sensitive hydrogel doped with BNNS-TA and Fe^(3+)ions is fabricated. The ternary BNNS-TA/Fe^(3+)/PAAm hydrogel exhibits excellent compressive strength(at least four times the compressive strength of unfilled pure PAAm hydrogel), pressure-sensitive performance(gauge factor is up to 1.4), and performance recovery due to the combination of multiple intermolecular interactions, such as covalent crosslinking, hydrogen bonds, and ion coordination interactions.The BNNS-TA/Fe^(3+)/PAAm hydrogel can be made as a pressure sensor installed in the control circuit or attached on the human body to detect human activities accurately. More importantly, the compressive strength and the pressure-sensitive performance of the BNNS-TA/Fe^(3+)/PAAm hydrogel can be maintained after the hydrogel is irradiated by^(60)Co gamma-ray at an absorbed dose of 15 k Gy. As a comparison, the compressive strength of the unfilled PAAm hydrogel is only a quarter of that before irradiation. This work not only reveals a facile method to achieve the preparation of chemically modified BNNS as a promising radiation-resistant additive but also provides a novel strategy for the development of pressure-sensitive hydrogel devices in radiation environments.

关键词： Pressure-sensitive hydrogel Polyacrylamide radiation resistance Boron nitride nanosheet Tannic acid Motion detection

Discovery of the inhibitor of DNA binding 1 as a novel marker for radioresistance in pancreatic cancer using genome-wide RNA-seq

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Cancer Drug resistance 2022年第4期5卷 926-938页

作者： scar Zuniga Stephanie Byrum Adam R.Wolfe Department of radiation Oncology University of Arkansas for Medical SciencesLittle RockAR 72205USA Department of Biochemistry and Molecular Biology University of Arkansas for Medical SciencesLittle RockAR 72205USA

Purpose/Objective(s): Discovery of genetic drivers of radioresistance is critical for developing novel therapeuticstrategies to combine with radiotherapy of radioresistant PDAC. In this study, we used genome-wide RNA-seq toidentify genes upregulated in generated radioresistant PDAC cell lines and discovered the Inhibitor of DNA Binding1 (ID1) gene as a potential regulator of radioresistance in PDAC.Materials/Methods: Radioresistant clones of the PDAC cell lines MIA PaCa-2 and PANC-1 were generated bydelivering daily ionizing irradiation (IR) (2 Gy/day) in vitro over two weeks (total 20 Gy) followed by standardclonogenic assays following one week from the end of IR. The generated RR and parental cell lines were submittedfor RNA-seq analysis to identify differentially expressed genes. The Limma R package was used to calculatedifferential expression among genes. Log2 fold change values were calculated for each sample compared to thecontrol. Genes with an absolute fold change > 1 were considered significant. RNA sequencing expression data fromthe Cancer Genome Atlas (TCGA) database was analyzed through the online databases GEPIA, cBioPortal, and theHuman Protein Atlas.Results: Following exposure to two weeks of 2 Gy daily IR in vitro, the two PDAC cell lines showed significantlygreater clonogenic cell survival than their parental cell lines, indicating enhanced RR in these cells. RNA-seqanalysis comparing parental and RR cell lines found upregulated seven genes (TNS4, ZDHHC8P1, APLNR, AQP3,SPP1, ID1, ID2) and seven genes downregulated (PTX3, ITGB2, EPS8L1, ALDH1L2, KCNT2, ARHGAP9, IFI16) in bothRR cell lines. Western blotting confirmed increased expression of the ID1 protein in the RR cell lines compared totheir parental cell lines. We found that ID1 mRNA was significantly higher in PDAC tumors compared to matchednormal and high ID1 expression correlated with significantly worse disease-free survival (DFS) in PDAC patients(HR = 2.2, log rank P = 0.009). ID1 mRNA expression was also strongly correlated in tumors with

关键词： Pancreatic cancer radiation resistance ID1 RNA-seq

Functional characterization of SAG/RBX2/ROC2/RNF7, an antioxidant protein and an E3 ubiquitin ligase

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Protein & Cell 2013年第2期4卷 103-116页

作者： Yi Sun Hua Li Division of radiation and Cancer Biology Department of Radiation OncologyUniversity of Michigan4424B Medical Science-I1301 Catherine StreetAnn ArborMI 48109USA.

SAG(Sensitive to Apoptosis Gene),also known as RBX2(RING box protein 2),ROC2(Regulator of Cullins 2),or RNF7(RING Finger Protein 7),was originally cloned in our laboratory as a redox inducible antioxi-dant protein and later characterized as the second member of the RBX/ROC RING component of the SCF(SKP1-CUL-F-box Proteins)E3 ubiquitin ligase.When acting alone,SAG scavenges oxygen radicals by forming inter-and intra-molecular disulfide bonds,whereas by forming a complex with other components of the SCF E3 ligase,SAG promotes ubiquitination and degradation of a number of protein substrates,includ-ing c-JUN,DEPTOR,HIF-1α,IκBα,NF1,NOXA,p27,and procaspase-3,thus regulating various signaling path-ways and biological processes.Specifically,SAG pro-tects cells from apoptosis,confers radioresistance,and plays an essential and non-redundant role in mouse embryogenesis and vasculogenesis.Furthermore,stress-inducible SAG is overexpressed in a number of human cancers and SAG overexpression correlates with poor patient prognosis.Finally,SAG transgenic expression in epidermis causes an early stage inhibi-tion,but later stage promotion,of skin tumorigenesis triggered by DMBA/TPA.Given its major role in pro-moting targeted degradation of tumor suppressive proteins,leading to apoptosis suppression and accel-erated tumorigenesis,SAG E3 ligase appears to be an attractive anticancer target.

关键词： antioxidant angiogenesis apoptosis Cullin-RING ligases radiation resistance reactive oxygen species SAG/RBX2/ROC2/RNF7 SCF E3 ligases tumori-genesis ubiquitin ligase vasculogenesis

Effect of Temperature and Gamma-Ray Irradiation on Optical Characteristics of Fiber Bragg Grating Inscribed radiation-Resistant Optical Fiber

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Photonic Sensors 2020年第1期10卷 16-33页

作者： Seongmin JU Youngwoong KIM Kadathala LINGANNA Yune Hyoun KIM Won-Taek HAN School of Electrical Engineering and Computer Science Gwangju Institute of Science and TechnologyGwangju 61005South Korea Smart Photonics Research Center/Advanced Optical Lens Research Center/Laser Research Center Korea Photonics Technology InstituteGwangju 61007South Korea

A new radiation-hard germano-silicate glass optical fiber with a pure silica glass buffer and a boron-doped silica glass inner cladding was fabricated for temperature sensor application based on the fiber Bragg grating(FBG)underg-ray irradiation environment.The temperature dependences of optical attenuation at 1550.5 nm and Bragg reflection wavelength shift from 18℃to 40℃before theγ-ray irradiation were about 4.57´10^(-4)dB/℃and 5.48 pm/℃,respectively.The radiation-induced optical attenuation at 1550.5 nm and the radiation-induced Bragg reflection wavelength shift under theγ-ray irradiation with the total dose of 22.85 kGy at 35℃were about 0.03 dB/m and 0.12 nm,respectively,with theγ-ray irradiation sensitivity of 5.25´10^(-3)pm/Gy.The temperature and theγ-ray irradiation dependence of optical attenuation at 1550.5 nm in the FBG written fiber with boron-doped silica glass inner cladding were about 6 times and 4 times lower than that in the FBG written fiber without boron-doped silica glass inner cladding under a temperature change from 18℃to 40℃and theγ-ray irradiation with the total dose of 22.85 kGy at 35℃,respectively.Furthermore,the effect of temperature increase on the Bragg reflection wavelength of the FBG written fiber with boron-doped silica inner cladding was much larger about 1000 times than that of theγ-ray irradiation.However,no influence on the reflection power of the Bragg wavelengths and the full width at half maximum(FWHM)bandwidth under temperature and theγ-ray irradiation change was found.Also,after theγ-ray irradiation with the dose of 22.85 kGy,no significant change in the refractive index was found but the residual stresses developed in the fiber were slightly relaxed or retained.

关键词： Optical fiber radiation resistance temperature sensor fiber Bragg grating radiation-induced attenuation

Recent progress of radiation response in nanostructured tungsten for nuclear application

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Tungsten 2021年第1期3卷 20-37页

作者： Hang Xu Lan-Li He Yong-Feng Pei Chang-Zhong Jiang Wen-Qing Li Xiang-Heng Xiao Hubei Nuclear Solid Physics Key Laboratory Department of PhysicsWuhan UniversityWuhan 430072China

Engineering materials for nuclear reactors exposed to high-dose irradiation breed various radiation damage,leading to performance degradation of materials,which seriously limits the application of materials in the future advanced nuclear reactors.Tungsten-based materials applied in future nuclear reactors have to withstand not only the attack of high-energy neutron and plasma,but also the repeated impact of steady-state or even transient thermal load.Researches in the past decades have proved that tailored nanostructure have advantage in annihilating radiation defects.With the rapid development of nanostructured tungsten,probing radiation application of nanostructured tungsten is of great significance in promoting the development of novel radiation-resistant materials.Herein,the development status of three kinds of nanostructured tungsten namely nanocrystalline,nanofilm and nanoporous tungsten designed for radiation tolerance and the performance enhancement mechanism of diverse nanostructure in irradiation environment is reviewed.Finally,future perspectives and technical challenges are discussed,to inspire more creative designs of novel nanostructured tungsten for radiation tolerance.

关键词： Tungsten Nanostructure radiation damage radiation resistance