利用重金属工艺可提高器件可靠性,低能γ将使器件高Z/低Z界面附近产生剂量增强效应,影响器件抗辐射性能评估。介绍了一种强钴源低能散射γ成分评价方法,利用铝单层室壁/金铝双层室壁平板型电离室辐射电流比值对γ能量敏感的特性,通过比...利用重金属工艺可提高器件可靠性,低能γ将使器件高Z/低Z界面附近产生剂量增强效应,影响器件抗辐射性能评估。介绍了一种强钴源低能散射γ成分评价方法,利用铝单层室壁/金铝双层室壁平板型电离室辐射电流比值对γ能量敏感的特性,通过比较电流比值实测与参考值的差异,估计散射γ(≤300 ke V)成分是否过多,典型钴源能谱计算结果表明:参考值可取为2.8。研制了量程为0.01~2.3 Gy·s^(-1)(Si)的电离室探头,搭建了长距离辐射电流测量系统。单板钴源实验结果表明:空场条件和铅铝容器(散射抑制)内辐射电流比值实测结果与预期相符,方法可行;能够检验能谱硬化技术的有效性;可从剂量角度关联不同辐射场或相同辐射场不同辐照工位。展开更多
移动卒中单元(mobile stroke unit,MSU)和第五代移动通信技术(5th generation mobile communication technology,5G)相结合构成了5G移动卒中单元(5G MSU),其在卒中急救方面表现出强大的应用潜力。5G MSU利用物联网、移动互联网、云计算...移动卒中单元(mobile stroke unit,MSU)和第五代移动通信技术(5th generation mobile communication technology,5G)相结合构成了5G移动卒中单元(5G MSU),其在卒中急救方面表现出强大的应用潜力。5G MSU利用物联网、移动互联网、云计算、5G等新一代信息通信技术,将MSU、急救中心、卒中中心和医疗机构等各模块有效地连接起来,改变了传统的卒中院前救治模式,将急救工作前移,实现"上车即入院"的目标,显著缩短了患者发病到静脉溶栓时间。在早期研究中,多项临床研究证实了MSU在急性卒中救治中的可行性和安全性,但其能否改善患者的预后及降低死亡率尚未明确。本文就5G MSU的概念、发展、国内外研究进展等内容进行综述。展开更多
The Xing'an Block (XB) is located between the Erguna
Block (EB) and the Songnen Block (SB), which
topographically occupies the northeastern half of the Great
Xing'an Range (Liu et al., 2017). The XB was
tr...The Xing'an Block (XB) is located between the Erguna
Block (EB) and the Songnen Block (SB), which
topographically occupies the northeastern half of the Great
Xing'an Range (Liu et al., 2017). The XB was
traditionally considered to be composed of a Precambrian
metamorphic basement and post-Cambrian cover.
However, the recent geochronological studies show that
the so-called "Precambrian metamorphic rocks^^ are much
younger in age and considered to be formed in the Early
Paleozoic, indicating no existence of the Precambrian
metamorphic basement.展开更多
The aim of this study is to prepare poly-L-lactide(PLLA)electrospun nanofibrous scaffolds coated with hippocampal neuron-derived extracellular matrix(N-ECM)and construct a novel neural tissue engineering scaffold.Neon...The aim of this study is to prepare poly-L-lactide(PLLA)electrospun nanofibrous scaffolds coated with hippocampal neuron-derived extracellular matrix(N-ECM)and construct a novel neural tissue engineering scaffold.Neonatal rat hippocampal neurons were seeded on PLLA nanofibers,and then decellularized to derive a cell-free extracellular matrix loaded N-ECM/PLLA modified scaffolds.The morphology and ingredients of N-ECM/PLLA were observed by scanning electron microscopy(SEM)and immunofluorescence staining respectively,and the cytocompatibility of the composite scaffolds was characterized by cell count kit-8(CCK-8)assay.The N-ECM was clearly identified loading on scaffolds when being imaged via SEM and immunofluorescence staining results showed that the N-ECM was made up of fibronectin and laminin.Most importantly,compared with tissue culture polystyrene and pure scaffolds,N-ECM/PLLA scaffolds could effectively facilitate the proliferation of rat adrenal neuroma cells(PC12 cells),indicating their better cell compatibilities.Based on the combination of N-ECM and PLLA biomaterials,the present study has fabricated a unique and versatile neural tissue engineering scaffold,offering a new thought for future neural tissue engineering.展开更多
文摘利用重金属工艺可提高器件可靠性,低能γ将使器件高Z/低Z界面附近产生剂量增强效应,影响器件抗辐射性能评估。介绍了一种强钴源低能散射γ成分评价方法,利用铝单层室壁/金铝双层室壁平板型电离室辐射电流比值对γ能量敏感的特性,通过比较电流比值实测与参考值的差异,估计散射γ(≤300 ke V)成分是否过多,典型钴源能谱计算结果表明:参考值可取为2.8。研制了量程为0.01~2.3 Gy·s^(-1)(Si)的电离室探头,搭建了长距离辐射电流测量系统。单板钴源实验结果表明:空场条件和铅铝容器(散射抑制)内辐射电流比值实测结果与预期相符,方法可行;能够检验能谱硬化技术的有效性;可从剂量角度关联不同辐射场或相同辐射场不同辐照工位。
文摘移动卒中单元(mobile stroke unit,MSU)和第五代移动通信技术(5th generation mobile communication technology,5G)相结合构成了5G移动卒中单元(5G MSU),其在卒中急救方面表现出强大的应用潜力。5G MSU利用物联网、移动互联网、云计算、5G等新一代信息通信技术,将MSU、急救中心、卒中中心和医疗机构等各模块有效地连接起来,改变了传统的卒中院前救治模式,将急救工作前移,实现"上车即入院"的目标,显著缩短了患者发病到静脉溶栓时间。在早期研究中,多项临床研究证实了MSU在急性卒中救治中的可行性和安全性,但其能否改善患者的预后及降低死亡率尚未明确。本文就5G MSU的概念、发展、国内外研究进展等内容进行综述。
基金supported by the China Geological Survey (grant No. DD20160047-02)the Young Scientists Fund of Shandong Province (grant No. ZR2016DB08)the Financial Fund of Shandong Province (grant No. 2017CXGC1604)
文摘The Xing'an Block (XB) is located between the Erguna
Block (EB) and the Songnen Block (SB), which
topographically occupies the northeastern half of the Great
Xing'an Range (Liu et al., 2017). The XB was
traditionally considered to be composed of a Precambrian
metamorphic basement and post-Cambrian cover.
However, the recent geochronological studies show that
the so-called "Precambrian metamorphic rocks^^ are much
younger in age and considered to be formed in the Early
Paleozoic, indicating no existence of the Precambrian
metamorphic basement.
基金Fundamental Research Funds for the Central Universities,China(No.16D110520)
文摘The aim of this study is to prepare poly-L-lactide(PLLA)electrospun nanofibrous scaffolds coated with hippocampal neuron-derived extracellular matrix(N-ECM)and construct a novel neural tissue engineering scaffold.Neonatal rat hippocampal neurons were seeded on PLLA nanofibers,and then decellularized to derive a cell-free extracellular matrix loaded N-ECM/PLLA modified scaffolds.The morphology and ingredients of N-ECM/PLLA were observed by scanning electron microscopy(SEM)and immunofluorescence staining respectively,and the cytocompatibility of the composite scaffolds was characterized by cell count kit-8(CCK-8)assay.The N-ECM was clearly identified loading on scaffolds when being imaged via SEM and immunofluorescence staining results showed that the N-ECM was made up of fibronectin and laminin.Most importantly,compared with tissue culture polystyrene and pure scaffolds,N-ECM/PLLA scaffolds could effectively facilitate the proliferation of rat adrenal neuroma cells(PC12 cells),indicating their better cell compatibilities.Based on the combination of N-ECM and PLLA biomaterials,the present study has fabricated a unique and versatile neural tissue engineering scaffold,offering a new thought for future neural tissue engineering.
