分类： 物理学 >> 核物理学 提交时间： 2023-06-18 合作期刊: 《Nuclear Science and Techniques》
摘要： We study in the framework of the Langevin model the influence of initial excitation energy (E*) of Hg compound nuclei (CNs) on the sensitivity of the excitation energy at scission (Esc*) to the nuclear friction strength (). It is shown that the sensitivity is enhanced substantially with increasing E*. Moreover, we find that the significant sensitivity of Esc* to at high E* is little affected by a marked difference in the neutron-to-proton ratio of a CN and in its size and fissility. Our findings suggest that, on the experimental side, a measurement of Esc* in energetic proton-induced spallation reactions can provide not only a sensitive but also a robust probe of nuclear dissipation in fission of highly excited nuclei. Further development of a suitable approach to spallation reaction is discussed.
分类： 天文学 >> 星系和宇宙学 提交时间： 2023-12-08
摘要： This paper presents a morphological investigation of the early-type spiral galaxy M81 (NGC 3031) through decomposition by fitting radial profiles of surface brightness using the software GALFIT, aimed at exploring structural components of M81 and quantifying their morphology. In this work, we adopt 6 types of decompositions with different numbers of morphological components, among which the most complicated one contains 5 components such as a bulge, a disk, a pair of outer spiral arms, a pair of inner spiral arms, and a galactic nucleus. The results show that, M81 hosts a classical bulge with the Sersic index 5.0; the morphology and the luminosity for the bulge are almost constant in the different decomposition types. The disk of M81 has the Sersic index 1.2 but the morphology and the luminosity are found sensitive to the inclusion of the inner spiral arms in the decomposition or not. The results of this work indicate that the combination of individual substructures has a considerable impact on the morphology of the galaxy as a mixture. On the basis of the results, the usability of the different types of decomposition is suggested in this work. The three-component decomposition, i.e., bulge + disk + nucleus, is applicable to statistics of large samples of galaxies; more complicated decomposition with spiral arms taken into account is suitable for precise measurements of individual galaxies in small samples. This work is based on the single-band Spitzer-The Infrared Array Camera (IRAC) 4.5 m image. In the future, we will carry out multi-wavelength decomposition, for the purpose of investigating spectral energy distributions and stellar population properties for the galactic substructures, and thereby deduce their formation history and evolution processes.
分类： 生物学 >> 生物医药 提交时间： 2017-05-10
Jun Song（1.2）
Ye-Wei Zhang
Ai-Hua Yao
Yue Yu
Zhi-Yuan Hua
Li-Yong PuGuo-Qiang Li
Xiang-Cheng Li
Feng Zhang
Guo-Qing Sheng
Xue-Hao Wang
摘要： This study was to investigate the effect of donor liver adenoviral cardiotrophin-1 (CT-1) gene transfer on early graft survival and function in rat small-for-size liver transplantation. We constructed a recombinant murine CT-1 adenoviral vector. Donor rats were transduced in vivo with adenoviruses expressing CT-1 (AdCT-1) or control vector (AdEGFP). Livers were harvested 4 days later, reduced to 40% of weight, and transplanted. A syngeneic rat orthotopic liver transplantation model was performed using 40% small-for-size grafts. Graft survival, liver function, hepatic architecture change, the degree of necrosis and apoptosis, and cell survival signaling pathways were assessed. AdCT-1 pretreatment markedly improved liver function and the survival of small-for-size grafts. In the CT-1 treatment group, hepatic architecture was well protected, apoptotic and necrotic cells were reduced; anti-apoptotic protein bcl-2 was up-regulated and proapoptotic cleaved caspase-3 was down-regulated, cell survival signaling pathways were activated by phosphorylation of protein kinase B (Akt), extracellular-regulated kinase (ERK) and Signal transducer and activator of transcription-3 (Stat- 3) after transplantation. In conclusion, donor liver adenoviral CT-1 transfer ameliorated ischemia/reperfusion injury by decreasing hepatic necrosis and apoptosis in small-for-size liver transplantation, mediated in part by activation of the Akt, ERK, and Stat-3 survival signaling pathways. These results may provide a potential clinical strategy to improve the outcome of small-for-size liver grafts.
点击量
通过
点击量
下载量
评论
待评议
