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61.
Frederick Wieland Lawrence Hawley Abe Feinberg Mike Di Loreto Leo Blume Joseph Ruffles Peter Reiher Brian Beckman Philip Hontalas Steven Bellenot David Jefferson 《Concurrency and Computation》1989,1(1):35-50
This paper analyzes the performance of a discrete-event combat simulation executed on a parallel processor under control of the Time Warp Operating System. Time Warp is in a class of distributed simulation methods called Optimistic methods which have proven to be useful over a wide range of simulations. The combat simulation used for this performance study, called STB88, is a division-corps model incorporating a number of different types of computations. The speed-up for three versions of this model on the Caltech/JPL Mark III Hypercube and the BBN Butterfly parallel processors was measured relative to an efficient sequential execution of the same model on the same hardware. The results indicate that STB88 version 1 achieves a speed-up of 28.6 on 60 Mark III processors, while STB88 version 2 achieves a speed-up of 36.8 on 100 Butterfly processors. Version 3 of STB88 achieved a speed-up of 38.5 on 128 Mark III processors. The versions differed only in their interface to Time Warp. On the Butterfly, the sequential execution completed in 2 hours, while the 100 processor execution completed in 3.2 minutes. 相似文献
62.
Homologous recombination (HR) is thought to be important for the repair of stalled replication forks in hyperthermophilic archaea. Previous biochemical studies identified two branch migration helicases (Hjm and PINA) and two Holliday junction (HJ) resolvases (Hjc and Hje) as HJ-processing proteins; however, due to the lack of genetic evidence, it is still unclear whether these proteins are actually involved in HR in vivo and how their functional relation is associated with the process. To address the above questions, we constructed hjc-, hje-, hjm-, and pina single-knockout strains and double-knockout strains of the thermophilic crenarchaeon Sulfolobus acidocaldarius and characterized the mutant phenotypes. Notably, we succeeded in isolating the hjm- and/or pina-deleted strains, suggesting that the functions of Hjm and PINA are not essential for cellular growth in this archaeon, as they were previously thought to be essential. Growth retardation in Δpina was observed at low temperatures (cold sensitivity). When deletion of the HJ resolvase genes was combined, Δpina Δhjc and Δpina Δhje exhibited severe cold sensitivity. Δhjm exhibited severe sensitivity to interstrand crosslinkers, suggesting that Hjm is involved in repairing stalled replication forks, as previously demonstrated in euryarchaea. Our findings suggest that the function of PINA and HJ resolvases is functionally related at lower temperatures to support robust cellular growth, and Hjm is important for the repair of stalled replication forks in vivo. 相似文献
63.
Mina Han Ikue Abe Jihun Oh Jaehoon Jung Young Ji Son Jaegeun Noh Mitsuo Hara Takahiro Seki 《International journal of molecular sciences》2022,23(2)
Fluorescent molecular assembly systems provide an exciting platform for creating stimuli-responsive nano- and microstructured materials with optical, electronic, and sensing functions. To understand the relationship between (i) the plausible molecular structures preferentially adopted depending on the solvent polarity (such as N,N-dimethylformamide [DMF], tetrahydrofuran [THF], and toluene), (ii) the resulting spectroscopic features, and (iii) self-assembled nano-, micro-, and macrostructures, we chose a sterically crowded triangular azo dye (3Bu) composed of a polar molecular core and three peripheral biphenyl wings. The chromophore changed the solution color from yellow to pink-red depending on the solvent polarity. In a yellow DMF solution, a considerable amount of the twisted azo form could be kept stable with the help of favorable intermolecular interactions with the solvent molecules. By varying the concentration of the DMF solution, the morphology of self-assembled structures was transformed from nanoparticles to micrometer-sized one-dimensional (1D) structures such as sticks and fibers. In a pink-red toluene solution, the periphery of the central ring became more planar. The resulting significant amount of the keto-hydrazone tautomer grew into micro- and millimeter-sized 1D structures. Interestingly, when THF-H2O (1:1) mixtures were stored at a low temperature, elongated fibers were stacked sideways and eventually developed into anisotropic two-dimensional (2D) sheets. Notably, subsequent exposure of visible-light-irradiated sphere samples to solvent vapor resulted in reversible fluorescence off↔on switching accompanied by morphological restoration. These findings suggest that rational selection of organic dyes, solvents, and light is important for developing reusable fluorescent materials. 相似文献
64.
Sho Kano Huilong Yang John McGrady Tomonori Ihara Hazuku Tatsuya Hiroaki Abe 《Journal of Nuclear Science and Technology》2019,56(3):300-309
The radiation-induced surface activation (RISA) effect will be applied to the core design in supercritical light water reactor (SCWR) in order to achieve a high performance with excellent economy and safety. The purpose of the present study is to investigate the RISA effect in the candidate fuel cladding materials in SCWR such as PNC1520. The change of weldability due to RISA effect and the related microstructure analysis were performed in oxidized PNC1520 and 304 stainless steel with various oxidization periods. The phases contained in the surface oxide layer of the present specimen were identified as Fe2CrO4, γ-Fe2O3, and Fe2O3. The lifetime of 13.8 days for wettability improving factor was confirmed in the ultraviolet (UV) irradiation. Meanwhile, the long life of 13.8 days and short life of 0.8 days for wettability improving factors were identified in the γ-ray irradiation. Based on the fact that the band gap energies of Fe2CrO4, γ-Fe2O3, and Fe2O3 were, respectively, 2.1, 2.0, and 2.2 eV, and the photo energies of UV and γ-ray irradiation were 4.48 eV and 13.3 MeV, it is therefore clarified that the hydrophilization on the oxide layer is ascribed to the RISA effect. 相似文献
65.
Watanabe Masahito Sato Fumiya Abe Raiki Ueda Kyosuke Matsuwaka Daisuke Kudo Fumiaki Narushima Takayuki 《Metallurgical and Materials Transactions B》2019,50(4):1553-1558
Metallurgical and Materials Transactions B - A two-step plasma arc melting process, comprising a first step under Ar-30 pct H2 gas flow and the second step under Ar gas flow, has been... 相似文献
66.
Plasma osmolality estimated from plasma concentrations of Na+, Cl-, K+, glucose, and urea was compared with measured osmolality in preweaned Holstein calves. When calves (n = 5) were fed only milk replacer after fasting for 24 h, measured osmolality fluctuated almost in parallel with estimated osmolality during the 8-h period after feeding, although estimated values were about 90% of measured values. When calves (n = 5) were fed only calf starter after fasting for more than 16 h, measured osmolality did not parallel the estimated osmolality during the 8-h period after feeding. Some factors depressed measured osmolality in the first 2 h. 相似文献
67.
Naoki Motomura Yuto Yamazaki Daiki Koga Shogo Harashima Xin Gao Yuta Tezuka Kei Omata Yoshikiyo Ono Ryo Morimoto Fumitoshi Satoh Yasuhiro Nakamura Go Eun Kwon Man Ho Choi Akihiro Ito Hironobu Sasano 《International journal of molecular sciences》2022,23(4)
Cortisol-producing adenoma (CPA) is composed of clear and compact cells. Clear cells are lipid abundant, and compact ones lipid poor but associated with higher production of steroid hormones. PRKACA mutation (PRKACA mt) in CPA patients was reported to be associated with more pronounced clinical manifestation of Cushing’s syndrome. In this study, we examined the association of histological features and genotypes with cholesterol uptake receptors and synthetic enzymes in 40 CPA cases, and with the quantitative results obtained by gas chromatography-mass spectrometry (GC-MS) analysis in 33 cases to explore their biological and clinical significance. Both cholesterol uptake receptors and synthetic enzymes were more abundant in compact cells. GC-MS analysis demonstrated that the percentage of compact cells was inversely correlated with the concentrations of cholesterol and cholesterol esters, and positively with the activity of cholesterol biosynthesis from cholesterol esters. In addition, hormone-sensitive lipase (HSL), which catalyzes cholesterol biosynthesis from cholesterol esters, tended to be more abundant in compact cells of PRKACA mt CPAs. These results demonstrated that both cholesterol uptake and biosynthesis were more pronounced in compact cells in CPA. In addition, more pronounced HSL expression in compact cells of PRKACA mt CPA could contribute to their more pronounced clinical manifestation. 相似文献
68.
Kiyomi Ohmori Asuka Kamei Yuki Watanabe Keiko Abe 《International journal of molecular sciences》2022,23(6)
The Bhas 42 cell transformation assay (Bhas 42 CTA) is the first Organization for Economic Cooperation and Development (OECD)-certificated method used as a specific tool for the detection of the cell-transformation potential of tumor-promoting compounds, including non-genotoxic carcinogens (NGTxCs), as separate from genotoxic carcinogens. This assay offers the great advantage of enabling the phenotypic detection of oncotransformation. A key benefit of using the Bhas 42 CTA in the study of the cell-transformation mechanisms of tumor-promoting compounds, including non-genotoxic carcinogens, is that the cell-transformation potential of the chemical can be detected directly without treatment with a tumor-initiating compound since Bhas 42 cell line was established by transfecting the v-Ha-ras gene into a mouse fibroblast cloned cell line. Here, we analyzed the gene expression over time, using DNA microarrays, in Bhas 42 cells treated with the tumor-promoting compound 12-O-tetradecanoylphorbol-13-acetate (TPA), and NGTxC, with a total of three repeat experiments. This is the first paper to report on gene expression over time during the process of cell transformation with only a tumor-promoting compound. Pathways that were activated or inactivated during the process of cell transformation in the Bhas 42 cells treated with TPA were related not only directly to RAS but also to various pathways in the hallmarks of cancer. 相似文献
69.
Two dimensional standards are important materials which are used in the calibration and the verification of coordinate measuring machines. In several countries, the national metrology institutes or accredit laboratories provide the calibration services of the two dimensional standards such as ball plates, hole plates and grid plates. The metrological equivalence of the measurement standards among the calibration providers is validated through the key comparison program. In the previous key comparison for a ball plate and a hole plate, the equivalences among the participants’ calibration results were verified on the distances between the No. 1 ball/hole (i.e., the origins of the workpiece coordinates) and other balls/holes on the plates respectively. The essential measurands of the two dimensional standards are the coordinates of the feature points, however, the measurement equivalences on them have not been verified. In this study, the authors propose the coordinates-based evaluation of the reference values and their uncertainty in two dimensional standard calibration comparison. 相似文献
70.
Yoshitaka Chikazawa Atsushi Katoh Hiroyuki Obata Masayuki Uzawa Kazuhiro Koga Ryo Chishiro 《Journal of Nuclear Science and Technology》2013,50(4):437-447
A simplified fuel handling system design for the demonstration Japan sodium-cooled fast reactor (JSFR) has been proposed. Fast Reactor Cycle Technology Development project phase I results of key technology evaluations on a pantograph fuel handling machine (FHM), a fuel transfer pot with two core component positions, dry spent fuel cleaning and minor actinide-bearing fresh fuel shipping cask are summarized. A full-scale FHM mockup has been fabricated and tested in the air accumulating performance and seismic tolerance data. A mockup fuel transfer pot with fins and chromium carbide coating has been fabricated and tested with sodium accumulating heat transfer performance data. Several sodium cleaning tests using a dummy subassembly has been conducted accumulating cleaning performance data. For fresh fuel shipping cask, a design tool for evaluation of heat transfer capability has been developed and a helium gas cask shows cooling capability of minor actinide-bearing fresh fuel. Those experimental and analytical efforts have shown that key technologies to develop simplified fuel handling system are matured enough to proceed large-scale sodium experiments and conceptual design study for the demonstration JSFR. 相似文献