No abstract available

[en] The method on temperature drift correction of energy spectrum measured by seawater in-situ γ-ray spectrometer composed of NaI(Tl) detector is studied. The method is based on the improvement of temperature compensation device powered by POE to design the experiment and explore the function relationship of measuring energy spectrum with temperature. Meanwhile the correction function about the peak shift with temperature is obtained utilizing curve fitting and used to correct the peak shift. The results show that the certain correspondence between the peak shift of the energy spectrum from γ spectrometer and the temperature variation is observed. The validity of the modified function is verified by the ⁶⁰Co and ¹⁵²Eu. Finally, this method provides a reference for the accurate measurement of seawater radionuclide recognition and nuclide activity. (authors)

[en] Objective: To clarify the mechanism of immediate early response gene 5 (Ier5) transcription induced by radiation. Methods: Deletant construction, site-specific mutagenesis,electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP) were used to forecast the promoter region, binding sites and transcription factors of Ier5 gene in HeLa cells. Results: The promoter region of Ier5 gene might be in the region of Ier5 -8 deletant (-408 - -238 bp). The Ier5 gene had two transcription factors of GCF and NFI, and GCF had two binding sites located in the region of -388 - -382 bp and -274 - -270 bp of Ier5 promoter. The binding site of NFI was located in -362 - -357 bp of Ier5 promoter. GCF could inhibit the expression of Ier5 gene and this inhibition was diminished when the radiation dose increased. In contrast, NFI increased the expression of Ier5. Conclusions: The most possible region of Ier5 promoter is from -408 to -238 bp which has two binding sites for the radiosensitivity transcription factors of GCF and NFI that could negatively and positively regulate the expression of Ier5 respectively. (authors)

[en] Through radiation measurement of in-site system equipment in three types of reactors during overhauling, the typical types of radio-nuclides and the energy range of β ray existed in nuclear power plants (NPPs) were obtained. The surface activity responses to β rays with different energy of some common-used β surface contamination monitors were experimentally investigated. It is found that using the surface activity response of ⁹⁰Sr-⁹⁰Y plane source to calibrate these monitors would underestimate the real level of surface contamination. With respect to the energy range of β ray in NPPs, it is suggested that ²⁰⁴Tl or ³⁶Cl would be employed to calibrate the surface activity response of β surface contamination monitors. (authors)

[en] The design of a new type of GM Tube radiation detector was introduced. The detector was designed according to the principle of Time-to-Count method. The hardware structure and program flow design of the radiation detector were presented. The test results showed that the linearity of Time-to-Count method is better than pulse counting method. Besides, the range upper limit based on Time-to-Count method extended two orders of magnitudes compared with the traditional pulse counting method. (authors)

[en] The field of ground-based gamma-ray astronomy has enjoyed rapid growth in recent years. As an increasing number of sources are detected at TeV energies, the field has matured and become a viable branch of modern astronomy. Lying at the uppermost end of the electromagnetic rainbow, TeV photons are always preciously few in number but carry essential information about the particle acceleration and radiative processes involved in extreme astronomical settings. Together with observations at longer wavelengths, TeV gamma-ray observations have drastically improved our view of the universe. In this review, we briefly describe recent progress in the field. We will conclude by providing a personal perspective on the future of the field, in particular, on the significant roles that China could play in advancing this young but exciting field. (invited reviews)

[en] We investigate the quantum parameter estimation in circuit quantum electrodynamics via dispersive measurement. Based on the Metropolis–Hastings algorithm and the Markov chain Monte Carlo (MCMC) integration, a new algorithm is proposed to calculate the Fisher information by the stochastic master equation. The Fisher information is expressed in the form of log-likelihood functions and further approximated by the MCMC integration. Numerical results show that the evolution of the Fisher information can approach the quantum Fisher information in a short time interval. These results demonstrate the effectiveness of the proposed algorithm. Finally, based on the proposed algorithm, we consider the effects of the measurement operator and the measurement efficiency on the Fisher information.

[en] Purpose: To compare the relative accuracy of left ventricular volume measured by electron-beam computed tomography (EBCT) and conventional cineangiography. Materials and methods: Fourteen human left ventricular casts underwent electron-beam computed tomography scanning and conventional biplane cineangiography. The true left ventricular volume was measured by displacement of water. EBCT left ventricular volume was calculated with modified Simpson's method, the cineangiographic left ventricular volume was calculated with biplane area-length method. Results: The actual left ventricular cast volume was 55.57 +- 28.91 ml, EBCT left ventricular volume was 66.50 +- 33.04 ml for long-axis view, and 60.36 +- 29.90 ml for short-axis view, ventricular volume from biplane cineangiography was 82.09 +- 40.40 ml. Left ventricular volume from biplane cineangiography was significantly larger than those from EBCT and the actual volume (P<0.001). The overestimation of left ventricular volume by biplane cineangiography (26.52 +- 16.11 ml) was more obvious than those by BECT (4.79 +- 6.59 ml for short-axis view and 10.93 +- 8.14 ml for long-axis view). The linear correlation analysis showed that there was very close correlation between EBCT ventricular volume, cineangiographic ventricular volume, and true ventricular volume (all r>0.98). Conclusion: EBCT is more accurate for left ventricular volume measurement and should become the gold standard

[en] Combining archival data taken at radio and infrared wavelengths with state-of-the-art measurements at X-ray and gamma-ray energies, we assembled a broadband spectral energy distribution (SED) of Cas A, a young supernova remnant. Except for strong thermal emission at infrared and X-ray wavelengths, the SED is dominated by non-thermal radiation. We attempted to model the non-thermal SED with a two-zone leptonic model which assumes that the radio emission is produced by electrons that are uniformly distributed throughout the remnant while the non-thermal X-ray emission is produced by electrons that are localized in regions near the forward shock. Synchrotron emission from the electrons can account for data from radio to X-ray wavelengths. Much of the GeV-TeV emission can also be explained by a combination of bremsstrahlung emission and inverse Compton scattering of infrared photons. However, the model cannot fit a distinct feature at GeV energies. This feature can be well accounted for by adding a π⁰ emission component to the model, providing evidence for cosmic ray production in Cas A. We discuss the implications of these results.

[en] Circular RNAs (circRNAs) play a critical role during hepatocellular carcinoma (HCC) development. CircRNA PTPRM (circPTPRM) has not been reported to cause disease and its role in HCC is unclear. This study explored circRNA expression and the function of circPTPRM in HCC. RNA sequencing (RNA-seq) was performed on 3 randomly selected pairs of HCC tissues and their corresponding adjacent non-tumor tissues. Three differentially expressed circRNAs, circPTPRM, circSMAD2 and circPTBP3 were selected and verified by real-time quantitative reverse transcription-polymerase chain reactions in 30 pairs of tissue samples, In vitro cultured hepatoma cells, and normal liver cells. Clinical data analysis was performed to select target circRNAs. Anti-target circRNA siRNAs were transfected into hepatoma cell lines, and the biological behavior of hepatoma cells following silencing of the target circRNA were detected by cell proliferation, plate cloning, and transwell assays. There were 86 differentially expressed circRNAs from RNA-seq, of which 53 were significantly upregulated and 33 were significantly downregulated in HCC. CircPTPRM expression was significantly upregulated in HCC tissue (p = 0.023) based on the analysis of 30 paired samples. CircPTPRM expression positively correlated with HCC recurrence and metastasis (p = 0.039). CircPTPRM silencing reduced HCC cell proliferation, migration and invasion. CircRNAs were differentially expressed in HCC samples. CircPTPRM was significantly upregulated in HCC and may function during the tumorigenesis and metastasis of HCC.