The development of radiation hydrodynamical methods that are able to follow gas dynamics and radiative transfer (RT) self‐consistently is key to the solution of many problems in numerical astrophysics. Such fluid flows are highly complex, rarely allowing even for approximate analytical solutions against which numerical codes can be tested. An alternative validation procedure is to compare different methods against each other on common problems, in order to assess the robustness of the results and establish a range of validity for the methods. Previously, we presented such a comparison for a set of pure RT tests (i.e. for fixed, non‐evolving density fields). This is the second paper of the Cosmological Radiative Transfer Comparison Project, in which we compare nine independent RT codes directly coupled to gas dynamics on three relatively simple astrophysical hydrodynamics problems: (i) the expansion of an H ii region in a uniform medium, (ii) an ionization front in a 1/r2 density profile with a flat core and (iii) the photoevaporation of a uniform dense clump. Results show a broad agreement between the different methods and no big failures, indicating that the participating codes have reached a certain level of maturity and reliability. However, many details still do differ, and virtually every code has showed some shortcomings and has disagreed, in one respect or another, with the majority of the results. This underscores the fact that no method is universal and all require careful testing of the particular features which are most relevant to the specific problem at hand.
We report the first ionization potentials (IP 1 ) of the heavy actinides, fermium (Fm, atomic number Z = 100), mendelevium (Md, Z = 101), nobelium (No, Z = 102), and lawrencium (Lr, Z = 103), determined using a method based on a surface ionization process coupled to an online mass separation technique in an atom-at-a-time regime. The measured IP 1 values agree well with those predicted by state-of-the-art relativistic calculations performed alongside the present measurements. Similar to the well-established behavior for the lanthanides, the IP 1 values of the heavy actinides up to No increase with filling up the 5f orbital, while that of Lr is the lowest among the actinides. These results clearly demonstrate that the 5f orbital is fully filled at No with the [Rn]5f 14 7s 2 configuration and that Lr has a weakly bound electron outside the No core. In analogy to the lanthanide series, the present results unequivocally verify that the actinide series ends with Lr.
The nuclide 266 Bh was produced in the 248 Cm( 23 Na,5n) 266 Bh reaction at beam energies of 125.9, 130.6, and 135.3 MeV. Decay properties of 266 Bh were investigated with a rotating wheel apparatus for α and spontaneous fission (SF) spectrometry under low background conditions attained by a gas-jet transport system coupled to the RIKEN gas-filled recoil ion separator. Based on genetically correlated α-α and α-SF decay chains, a total of 23 chains were assigned to 266 Bh and its daughter nuclide 262 Db and granddaughter 258 Lr. The half-life of 266 Bh was measured to be T 1/2 = 10.0 +2.6 −1.7 s which is an order of magnitude longer than the literature data. The α-particle energies of 266 Bh disperse widely in the range of E α = 8.62-9.40 MeV. The maximum production cross section for the 248 Cm( 23 Na,5n) 266 Bh reaction was determined to be σ = 57 ± 14 pb at 130.6 MeV, whereas the upper limit for the 248 Cm( 23 Na,4n) 267 Bh reaction was σ 14 pb at 121.2 MeV. These cross sections are discussed by comparing with the literature data as well as the theoretical calculations.
The signal quality of holographic memory is greatly lowered by the pixel mismatch between the charge-coupled device (CCD) and the reproduced image caused by image distortion. This paper discusses an approach to improve the signal quality by using two step decoding method. By this method, first, distortion correction is done to improve the degree of pixel mismatch to obtain better signal to noise ratio (SNR). Then, to eliminate errors such as noise that cannot be removed by distortion correction, soft decision Viterbi decoding using the newly defined reliability is used to correct errors. The effectiveness of this two step decoding method was tested by computer simulation, and its effect to improve SNR and reduce errors was confirmed.
Zebrafish embryos and larvae have become popular vertebrate models because their body walls are transparent, which enables live imaging of target organs using fluorescent protein transgenes or dye staining. Software packages for the quantification of these fluorescent signals are available from both commercial and noncommercial sources; however, their algorithms are complicated and their resources (code) have mostly not been openly shared. In this study, we developed a simple and robust open-source software tool named ''ZF-Mapper'' for the quantification of the fluorescence intensity of each pixel in zebrafish images with batch image file processing capability. Using this software, we can evaluate the three-dimensional (3D) distribution of fluorescence intensity among zebrafish cells by analyzing each image pixel. We tested ZF-Mapper for the analysis of zebrafish with macrophage-specific enhanced green fluorescent protein (EGFP) and obtained results that were equivalent to those acquired using the conventional image analysis software ImageJ. We further applied ZF-Mapper to the analysis of zebrafish with cancer cell xenografts and quantified the amount of implanted melanoma cells labeled with a tdTomato red fluorescent protein in the whole body and the tail region. In addition, by combining ZF-Mapper with R freeware, we created an interactive 3D scatter plot of the fluorescence intensities of macrophage-EGFPs in zebrafish. In summary, we developed the Python-based freeware ZF-Mapper for the quantification of fluorescent signals in multiple zebrafish images, which enables fluorescence-based zebrafish screening. We provide the source code and the executable application software for Windows (.exe) and macOS (.app).
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