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[en] We report an alternative reconstruction technique for x-ray differential phase-contrast computed tomography (DPC-CT). This approach is based on a new phase line integral projection retrieval filter, which is rooted in the derivative property of the Fourier transform and counteracts the differential nature of the DPC-CT projections. It first retrieves the phase line integral from the DPC-CT projections. Then the standard filtered back-projection (FBP) algorithms popular in x-ray absorption-contrast CT are directly applied to the retrieved phase line integrals to reconstruct the DPC-CT images. Compared with the conventional DPC-CT reconstruction algorithms, the proposed method removes the Hilbert imaginary filter and allows for the direct use of absorption-contrast FBP algorithms. Consequently, FBP-oriented image processing techniques and reconstruction acceleration softwares that have already been successfully used in absorption-contrast CT can be directly adopted to improve the DPC-CT image quality and speed up the reconstruction

[en] A new method was developed for analysing the positron lifetime spectra on the graphical display screen of an IBM PC. The multi-exponential function model was used and the lifetime components of the spectrum were stripped one by one from the longest to the shortest while the graphics on the display screen were changing correspondingly. The obtained initial parameters of a lifetime spectrum are efficient and good enough to be used by the IBM PC (Professional) POSITRONFIT Program as input data

[en] The parts concerning input and output statements of the original POSITRONFIT program were largely added, modified and readjusted to meet the needs of the PC-DOS operating system. The POSITRONFIT program was compiled successfully by using IBM/PC FORTRAN Compiler V2.00 and IBM Professional FORTRAN Compiler V1.14. The real variables in the program were all expressed by 8 bytes of double precision ones and the precision was better than that on B6700 or IBM370. The typical computational time is 100 seconds, which is a little longer than that on B6700 computer

[en] On the basis of the generalized invariant theory, the invariant-related unitary transformation method is developed and used to study the evolution of the third-quantized wave function of the universe. The expressions for the phases and the wave functions are obtained. Then, by means of the construction of the coherent state, the solutions of the Wheeler-DeWitt equation and the quantum fluctuations caused by the third quantization are found

[en] Objective: To discuss the imaging features and changing patterns of bone marrow scintigraphy in myeloproliferative disorders (MPD) as well as its clinical significance. Methods: Bone marrow scintigraphy using ⁹⁹Tc^m-sulfur colloid 370-550 MBq was performed on 85 MPD patients, including 40 cases of idiopathic myelofibrosis (IMF), 15 of polycythemia vera (PV), 5 of essential thrombocythaemia (ET), 30 of chronic granulocytic leukemia. Also, 40 cases of myelodysplastic syndromes (MDS) were observed in this study. Results: Abnormal bone marrow imaging was found in 88.2% of the 85 patients. The suppression rate of central bone marrow (CBM) and expansion rate of peripheral bone marrow (PBM) in these MPD patients were 61.2% and 56.5%, respectively. The imaging patterns was classified into three types according to the distribution and activity of bone marrow. 1) reduced imaging (31.8%); 2) increased and expanded imaging (27.1%); 3) depressed and expanded imaging (29.4%). Splenomegaly with minimal residual marrow activity was typical for late stages of MPD. Expansion of PBM was the further feature, but of no major importance for improving hematopoiesis of MPD, and it tended to retract during clinical recovery in chronic granulocytic leukemia (CGL). With expanding PBM, unmatched peripheral blood decreasing was found in MDS. The expansion pattern of PBM in different MPD was of relatively definite features. Conclusions: The imaging pattern of bone marrow was correlated with blood work-up data and clinical course or stages of MPD. Bone marrow scintigraphy may be proven useful in differential diagnosis and evaluation of clinical staging and prognosis of MPD

[en] The High Temperature Reactor Pebble-bed Module Demonstration Project (hereinafter referred as HTR-PM Demonstration Project) is a commercialization nuclear power project with safety features of the fourth generation nuclear energy systems. Located in Shidao Bay, Rongcheng, Shandong, P. R. China, HTR-PM Demonstration Project is built with Chinese independent design and research, possessing the characteristic of inherent safety, simple systems, high power generation efficiency, extensive scope of applications and so on. Since the kick-off construction in December 2012, HTR-PM Demonstration Project has made smooth progress in civil works and installation, significant progress has been made in technology research and development, engineering design, equipment manufacturing, nuclear fuel supply, commissioning and operation preparation and other domains. This paper gives a brief overview on technical features and current progress of the HTR-PM Demonstration Project. (author)

[en] Quasi-classical trajectory (QCT) calculations have been performed to study the product polarization behaviours in the reaction O(³P) + D₂ (v = 0, j = 0) → OD + D. By running trajectories on the ³A' and ³A″ potential energy surfaces (PESs), vector correlations such as the distributions of the polarization-dependent differential cross sections (PDDCSs), the angular distributions of P(θ_r) and P(φ_r) are presented. Isotope effect is discussed in this work by a comprehensive comparison with the reaction O(³P) + H₂ (v = 0, j = 0) → H + H. Common characteristics as well as differences are discussed in product alignment and orientation for the two reactions. The isotope mass effect differs on the two potential energy surfaces: the isotope mass effect has stronger influence on P(θ_r) and PDDCSs of the ³A' PES while the opposite on P(φ_r) of the ³A″ potential energy surface. (atomic and molecular physics)

[en] Highlight: •MiR-21 plays a significant role in 5-FU resistance. •This role might be attributed to targeting of hMSH2 as well as TP and DPD via miR-21 targeted hMSH2. •Indirectly targeted TP and DPD to influence 5-FU chemotherapy sensitivity. -- Abstract: 5-Fluorouracil (5-FU) is a classic chemotherapeutic drug that has been widely used for colorectal cancer treatment, but colorectal cancer cells are often resistant to primary or acquired 5-FU therapy. Several studies have shown that miR-21 is significantly elevated in colorectal cancer. This suggests that this miRNA might play a role in this resistance. In this study, we investigated this possibility and the possible mechanism underlying this role. We showed that forced expression of miR-21 significantly inhibited apoptosis, enhanced cell proliferation, invasion, and colony formation ability, promoted G1/S cell cycle transition and increased the resistance of tumor cells to 5-FU and X radiation in HT-29 colon cancer cells. Furthermore, knockdown of miR-21 reversed these effects on HT-29 cells and increased the sensitivity of HT-29/5-FU to 5-FU chemotherapy. Finally, we showed that miR-21 targeted the human mutS homolog2 (hMSH2), and indirectly regulated the expression of thymidine phosphorylase (TP) and dihydropyrimidine dehydrogenase (DPD). These results demonstrate that miR-21 may play an important role in the 5-FU resistance of colon cancer cells

[en] According to the law and character of operation for high flux engineering test reactor (HFETR), the plan and practice of management by computer are discussed. In process of management by computer, several data base has been set up. Technical management by computer can pledge better safe of operation and test in HFETR, at the same time, the quality and efficient of technical management have been raised up in HFETR