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91.
Bioluminescence (BL) is an excellent optical readout for bioassays and molecular imaging. Herein, we accomplished new near infrared bioluminescence resonance energy transfer (NIR-BRET) templates for monitoring molecular events in cells with higher sensitivity. We first identified the best resonance energy donor for the NIR-BRET templates through the characterization of many coelenterazine (CTZ)–marine luciferase combinations. As a result, we found that NLuc–DBlueC and ALuc47–nCTZ combinations showed luminescence in the blue emission wavelength with excellent BL intensity and stability, for example, the NLuc–DBlueC and ALuc47–nCTZ combinations were 17-fold and 22-fold brighter than their second highest combinations, respectively, and were stably bright in living mammalian cells for at least 10 min. To harness the excellent BL properties to the NIR-BRET systems, NLuc and ALuc47 were genetically fused to fluorescent proteins (FPs), allowing large “blue-to-red” shifts, such as LSSmChe, LSSmKate2, and LSSmNep (where LSS means Large Stokes Shift). The excellent LSSmNep–NLuc combination showed approximately 170 nm large resonance energy shift from blue to red. The established templates were further utilized in the development of new NIR-BRET systems for imaging steroid hormone activities by sandwiching the ligand-binding domain of a nuclear receptor (NR-LBD) between the luciferase and the FP of the template. The NIR-BRET systems showed a specific luminescence signal upon exposure to steroid hormones, such as androgen, estrogen, and cortisol. The present NIR-BRET templates are important additions for utilizing their advantageous imaging of various molecular events with high efficiency and brightness in physiological samples.  相似文献   
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93.
DNA methylation of both viral and host DNA is one of the major mechanisms involved in the development of Epstein–Barr virus-associated gastric carcinoma (EBVaGC); thus, epigenetic treatment using demethylating agents would seem to be promising. We have verified the effect of MC180295, which was discovered by screening for demethylating agents. MC180295 inhibited cell growth of the EBVaGC cell lines YCCEL1 and SNU719 in a dose-dependent manner. In a cell cycle analysis, growth arrest and apoptosis were observed in both YCCEL1 and SNU719 cells treated with MC180295. MKN28 cells infected with EBV were sensitive to MC180295 and showed more significant inhibition of cell growth compared to controls without EBV infection. Serial analysis of gene expression analysis showed the expression of genes belonging to the role of BRCA1 in DNA damage response and cell cycle control chromosomal replication to be significantly reduced after MC180295 treatment. We confirmed with quantitative PCR that the expression levels of BRCA2, FANCM, RAD51, TOP2A, and CDC45 were significantly decreased by MC180295. LMP1 and BZLF1 are EBV genes with expression that is epigenetically regulated, and MC180295 could up-regulate their expression. In conclusion, MC180295 inhibited the growth of EBVaGC cells by suppressing DNA repair and the cell cycle.  相似文献   
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95.
We propose a methodology to optimize radiation protection in radioactive waste disposal after the closure of a disposal facility based on a probabilistic approach. In this methodology, a set of alternative options of the disposal system design with the associated uncertainties estimated through a probabilistic approach are developed. Then, the methodology evaluates the advantages and disadvantages of each option for the optimization of radiation protection, in which it is possible to determine the compliance with a dose constraint of 0.3 mSv/y and to collect information for making a decision on the optimization. In particular, the obtained information on the exposure, which is the mode and width of the dose distribution, can be converted into information on engineering measures and site conditions for the options. This process allows us to discuss which option should be selected as the optimal option by considering the balance between the exposure and the engineering, economic, and social feasibility of the option. This methodology is helpful for providing clear reasons why an optimal disposal system design is selected by combining quantitative information on the exposure and the feasibility of each option.  相似文献   
96.
A neutron-scanning device was developed for measuring accurate neutron densities of BWR high burn-up fuels up to 65 GWd tU−1. Characteristic test of this device was done with a 252Cf source and adopted to measure axial distributions of neutron densities of BWR spent fuels with various enrichments (2.0–3.4%), which had been irradiated up to 60 GWd tU−1 at Fukushima Daini Nuclear Power Station Unit 2(2F-2). We found the measured neutron densities were proportional to about fourth power of the corresponding burn-up values. The neutron densities calculated by the ORIGEN2.1 code and various cross section libraries showed good agreements with the measured ones in profile and absolute value except for BWR-UE file mainly based on ENDF/B-IV. The BS240J32 library based on JENDL3.2 was the best among the investigated libraries.  相似文献   
97.
Airborne substances can stimulate both the olfactory and the trigeminal nerve in the nose, giving rise to odor and pungent (irritant) sensations, respectively. Nose, eye, and throat irritation constitute common adverse effects in indoor environments. We measured odor and nasal pungency thresholds for homologous aliphatic aldehydes (butanal through octanal) and carboxylic acids (formic, acetic, butanoic, hexanoic, and octanoic). Nasal pungency was measured in subjects lacking olfaction (i.e., anosmics) to avoid odor biases. Similar to other homologous series, odor and pungency thresholds declined (i.e., sensory potency increased) with increasing carbon chain length. A previously derived quantitative structure-activity relationship (QSAR) based on solvation energies predicted all nasal pungency thresholds, except for acetic acid, implying that a key step in the mechanism for threshold pungency involves transfer of the inhaled substance from the vapor phase to the receptive biological phase. In contrast, acetic acid - with a pungency threshold lower than predicted - is likely to produce threshold pungency through direct chemical reaction with the mucosa. Both in the series studied here and in those studied previously, we reach a member at longer chain-lengths beyond which pungency fades. The evidence suggests a biological cut-off, presumably based upon molecular size, across the various series.  相似文献   
98.
The authors have proposed a method of reducing the energy consumption in residential buildings by providing household members with information on energy consumptions in their own houses. An on-line interactive “energy-consumption information system” that displays power consumptions of, at most, 18 different appliances, power and city-gas consumption of the whole house and room temperature, for the purpose of motivating energy-saving activities has been constructed and the effectiveness of the system investigated by installing it in 10 residential buildings. The experiment showed that energy-saving consciousness was raised and energy consumption was in fact reduced by the energy-saving activities of the household members. In this paper, the system is described in detail and the effectiveness of reducing energy-consumption of the whole house and for space heating will be discussed. Also the energy-saving activities in a certain household are shown by using load duration curves.  相似文献   
99.
This study examines the performance of “string-of-beads” liquid flow on vertical wires as a novel gas-liquid contact device for gas absorption using a chemically reacting liquid absorbent. The string-of-beads flow is a distinct on-wire liquid-flow pattern consisting of annular thin liquid films sheathing a wire and teardrop-shaped liquid beads alternately aligned on the wire at regular intervals. We have performed experiments of CO2 absorption by an aqueous monoethanolamine solution in string-of-beads flow on a single wire and have developed an analytic gas-absorption model relevant to the experiments. The model well simulates the CO2-absorption characteristics observed in the experiments, thereby suggesting the utility of the model in predicting the chemical gas-absorption performance of multiple-wire gas-liquid contactors.  相似文献   
100.
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