最新刊期
卷 37 ， 期 4 ， 2019
- “在真空中对烯烃嵌段共聚物进行电子束辐照，研究了吸收剂量对其交联程度、力学性能、结晶和二重形状记忆效应的影响。”摘要：The effects of electron-beam radiation, under vacuum, on the tensile property, re-crystallized structure, and dual-shape memory effect of an olefin block copolymer (OBC) were studied through stress-strain measurements, X-ray diffraction (XRD), and observation of strain recovery. The results showed that the gel content and strength at 100% strain increased for an absorbed dose of 50~250 kGy, whereas the elongation at break decreased with the increasing absorbed doses. The tensile strength increased when the absorbed dose was 50~150 kGy and decreased at 150~250 kGy. The XRD results demonstrated that electron-beam-induced selective crosslinking in the soft segment of the OBC did not influence the recrystallized structure but that crosslinking at higher doses slightly influenced the diffusion and rearrangement of the hard segment during recrystallization. The crosslinked OBC samples exhibit outstanding melt strength and dual-shape memory effect based on the observation of strain recovery. Both the shape fixity and recovery ratio are greater than 93%.关键词：Olefin block copolymer;Electron-beam radiation;Crosslinking;Crystal structure;Shape memory effect36|50|0更新时间：2025-03-03
RADIATION CHEMISTRY
- “最新研究发现，电离辐射可能通过激活小胶质细胞和NLRP3炎性小体，诱导炎症因子释放，引起认知功能障碍。”摘要：To explore the potential mechanism of cognitive impairment induced by ionizing radiation， twenty Kunming female mice were randomly divided into control group and irradiation group. The mice in the irradiation group received a single whole body irradiation of 137Cs γ-rays at an absorbed dose of 4 Gy. The novel object recognition test was used to evaluate the cognitive function of mice 35 d after irradiation. The expression of the microglial marker ionized calcium binding adapter molecule-1 (IBA-1) in the prefrontal cortex was determined by immunohistochemical staining. Western blot was used to detect the expression of nucleotide-binding oligomerization domain such as receptor protein 3 (NLRP3), apoptosis-associated speck-like protein (ASC), cysteinyl aspartate specific proteinase-1 (Caspase-1), interleukin (IL)-1β, and IL-18 protein in the prefrontal cortex. The expression of IBA-1, NLRP3, ASC, and Caspase-1 mRNA in the prefrontal cortex was determined by reverse transcription polymerase chain reaction. The results showed that compared with the control group, the mice in the irradiation group had a low discrimination ratio in the novel object recognition test (38.39 ± 3.69 vs. 28.82 ± 2.08, p<0.05), had higher number of IBA-1 positive cells (138.2 ± 3.7 vs. 159.6 ± 6.9, p<0.05), and remarkably enhanced expression levels of NLRP3, ASC, Caspase-1 protein (1.000 ± 0.066 vs. 1.341 ± 0.119, p<0.05; 1.000 ± 0.073 vs. 1.298 ± 0.083, p<0.05; 1.000 ± 0.039 vs. 1.603 ± 0.159, p<0.01), and NLRP3 and ASC mRNA in the prefrontal cortex (1.000 ± 0.046 vs. 1.372 ± 0.071, p<0.01; 1.000 ± 0.068 vs. 1.225 ± 0.069, p<0.05). Meanwhile, compared with the control group, the expression of inflammatory factors IL-1β and IL-18 was up-regulated in the irradiation group (1.000 ± 0.033 vs. 1.167 ± 0.059, p<0.05; 1.000 ± 0.196 vs. 1.614 ± 0.163, p<0.05). The results indicate that ionizing radiation may induce cognitive dysfunction by activating the NLRP3 inflammasome in the prefrontal cortex of mice.关键词：Ionizing radiation;Prefrontal cortex;NLRP3 inflammasome;Cognitive dysfunction38|43|2更新时间：2025-03-03
- “在电磁脉冲辐射领域，研究揭示了WEMP辐照对正常细胞损伤的作用规律，为损伤机理模型提供实验依据。”摘要：The purpose of this study was to investigate the relationship between cell apoptosis and wide-band electromagnetic pulse (WEMP) irradiation parameters and to provide experimental data to establish the biophysics damage model for WEMP. Cell counting kit-8 was used to detect the cell viability changes after WEMP irradiation and flow cytometry assay was used to detect cell apoptosis after irradiation under different WEMP irradiation parameters. Under experimental conditions, field strength and number of pulses were observed to be the main factors that increased the apoptotic rate of human amniotic epithelial cells. Specifically, electric field intensity and number of pulses were determined to be the primary and secondary factors, respectively. The two factors were confirmed to interact with each other, that is, a logistic function was found to exist between the apoptotic rate and electric field strength.关键词：Wide-band electromagnetic pulse;Apoptosis;Variance analysisCLC TL7128|29|1更新时间：2025-03-03
- “在医学成像领域，专家基于EGSnrc程序对锥形束CT系统进行模块化建模，实现了图像散射校正，显著提高了图像质量。”摘要：Based on the EGSnrc program to modularize the core-beam CT (CBCT) system, this study simulated the imaging process entirely based on the accurate construction of the geometric and beam characteristics of the CBCT system. The scatter correction of CBCT images was realized through Monte Carlo simulations by separating the scatter fraction (mainly Compton and Rayleigh scatterings) that affects CBCT image quality based on the interaction between particles and matter. In the phantom images and real cases, the three-dimensionally reconstructed CBCT image significantly reduced the error of the scatter artifacts of the image after scatter correction. In addition, the CT value in the selected region of interest was compared with the planning CT image. The average value of the CT error value in both scan modes was reduced to less than 10 HU, MRSE values were reduced by 71.4%, and CNR values were increased by 19.8%. The scatter correction method significantly improves anatomical details and can be used for CBCT images.关键词：Core-beam CT (CBCT);Monte Carlo simulations;Scatter correction111|99|0更新时间：2025-03-03
- “在口腔肿瘤放射治疗领域，研究者分析了不同辐射源对舌鳞癌细胞基因表达的影响，为临床筛选相关分子标志物提供参考。”摘要：To investigate the effects of X-rays and carbon-ion irradiation on CAL-27 cells and identify the differentially expressed microRNA (miRNA), CAL-27 cells were irradiated with X-rays and heavy-ions. Colony survival and apoptosis rate were measured. The differentially expressed miRNAs among different cell groups were obtained by high throughput sequencing technique and analyzed by Kyoto encyclopedia of genes and genomes （KEGG） pathway enrichment analysis. After X-ray and heavy-ion irradiation, the survival rate of CAL-27 cells reduced to 88% and 71%, respectively and the rate of apoptosis increased from 1.9% in the control group to 13.9% and 30.4%, respectively. Compared with X-ray irradiated cells, 33 miRNAs were changed after heavy-ion irradiation, 12 of which were up-regulated and 21 were down-regulated. Fifteen pathways were further filtered out using the KEGG database. Compared with X-ray irradiation, heavy-ion irradiation had a greater effect on the expression of miRNAs in CAL-27 cells at the same dose. The mechanism may be related to the MAPK signal transduction pathways.关键词：Heavy ion;CAL-27 cell;MicroRNA;Irradiation25|42|1更新时间：2025-03-03
- “西咪替丁对低剂量率累积照射比格犬脾脏细胞凋亡及凋亡相关蛋白表达的影响研究，揭示了其辐射保护作用机制。”摘要：The aim of this study was to investigate the effect of cimetidine on spleen cell apoptosis and the expression of apoptosis-related proteins in Beagle dogs exposed to low-dose-rate radiation and to explore its mechanism of radioprotection. Twenty-four male Beagle dogs were divided into six groups: normal control group, model group, positive control group, and cimetidine-treated groups at doses of 5.33, 10.67, and 21.33 mg/kg. The dogs were irradiated with 60Co γ-rays at a rate of 0.040 8 mGy/min for 23 d. Cimetidine was administered intragastrically once daily during the irradiation period. At cumulative dose of 991.44 mGy, the apoptosis of spleen cells was observed by the TUNEL assay, and the expression of Bcl-2, Bax, and P53 in the spleen was detected by immunohistochemistry. A high dose of cimetidine significantly inhibited spleen cell apoptosis induced by irradiation. In addition, the expression of Bcl-2 in the spleen increased in the cimetidine groups. Moreover, the expression of Bax, caspase-3, and P53 was reduced and the change was statistically significant in the cimetidine groups. Cimetidine induced the expression of Bcl-2 and reduced the expression of Bax, caspase-3, and P53 in the spleen cells of Beagle dogs, thereby inhibiting apoptosis and protecting the spleen from cumulative exposure to low-dose-rate radiation.关键词：Cimetidine;Low-dose-rate radiation;Cell apoptosis;Spleen30|44|0更新时间：2025-03-03
RADIOBIOLOGY AND RADIOMEDICINE
- “最新研究揭示电力机车受电弓升降电磁辐射环境安全，远低于国际职业暴露限值。”摘要：This study examines changes in an electromagnetic environment caused by an electromagnetic pulse during lifting and dropping of pantograph. The following four working conditions were tested: a background environment with no locomotive, the running of a locomotive, and the two processes of lifting and dropping of pantograph. The measured power levels were converted into corresponding electric and magnetic field strengths and were compared with the occupational exposure limits defined in International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. The results showed that the peak value of an electromagnetic pulse during pantograph lifting appeared at a frequency of 458 MHz, the corresponding power level was -24.30 dBm, the electric field intensity was 2.02×10-1 V/m, and the magnetic field intensity was 5.37×10-4 A/m. The peak value of an electromagnetic pulse during pantograph dropping was presented at a frequency of 144 MHz, at a corresponding power level of -29.47 dBm, electric field intensity of 3.51×10-2 V/m, and magnetic field intensity of 9.31×10-5 A/m. The maximum electric and magnetic field intensities occurred during pantograph lifting, and their values were far smaller than the ICNIRP occupation exposure limits. The results thus indicate that the electromagnetic radiation environment generated by lifting and dropping of the pantograph is safe to occuptational workers.关键词：Pantograph;Electromagnetic pulse;Power level;Electric field strength;Magnetic field strength53|103|0更新时间：2025-03-03
RADIATION PROTECTION
- “最新研究发现，基于辐射敏感基因和SERS光谱技术的辐射探测方法，有望成为电离辐射剂量测量的新型探测手段。”摘要：A novel approach for detecting radiation damage to radiosensitive genes was developed using surface-enhanced Raman scattering (SERS) technology. Radiosensitive gene fragments were modified with thiol groups and immobilized onto the surface of gold nanoparticles (AuNPs) to form single-stranded and double-stranded DNA through Au-S bonds. SERS was used to analyze the response of DNA-AuNPs assemblies to γ-rays and the local enhancement effect of AuNPs on this response to γ-radiation. The results showed that the 663 cm-1 spectral peak of the double-stranded DNA-AuNPs assemblies varied with the dose range of γ-radiation (0 to ~200 Gy). Similarly, the single-stranded DNA-AuNPs showed a good response to γ-radiation in the dose range of 0~100 Gy, and the sensitivity of the DNA-AuNPs assembly noticeably increased with the increase in bound AuNPs. This positive correlation was due to the localized surface plasmon resonance of the AuNPs. The analysis of DNA-AuNPs assemblies using SERS scattering, could potentially be a novel method for the detection and measurement of ionizing radiation causing damage to genes.关键词：Radiosensitive gene;γ-radiation;Surface enhanced Raman scattering;Gold nanoparticles23|109|1更新时间：2025-03-03
- “在核废物桶检测领域，专家设计了分段γ扫描和层析γ扫描自动检测系统，实现了运动控制、能谱探测与数据分析的协同化、一体化。”摘要：A segmented gamma scanning and tomographic gamma scanning automatic detection system was designed to make the process of nuclear waste barrel detection more standardized and convenient. A motion control system was designed based on a Siemens S7-1200 programmable logic controller, and PC control and analysis software was developed based on the C# language. The accurate control of a mechanical motion device and orderly detection in a non-destructive assay system were realized. A human interface was designed to allow a user to control the experimental platform. Automatic mechanical control execution, data collection, and energy spectrum analysis were realized, while simultaneously providing auxiliary functions such as mode switching and security monitoring. This detection system promotes the synergy and integration of motion control, energy spectrum detection, and data analysis in an automatic detection process for barreled nuclear waste.关键词：Segmented gamma scanning (SGS);Tomographic gamma scanning (TGS);Automatic detection software;Solid nuclear waste35|78|1更新时间：2025-03-03
RADIATION INTERDISCIPLINARY RESEARCH
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