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991.
A major challenge of cancer biology is to visualize the dynamics of the metastatic process in secondary organs at high optical resolution in vivo real-time. Here, we presented intravital, dual-colored imaging of liver metastasis formation from a single cancer cell to metastatic colonies in the living liver of living mice using two photon laser scanning microscopy (TPLSM). Red fluorescent protein expressing murine (SL4) or human (HT29) colorectal cancer cell lines were inoculated to the spleen of green fluorescent protein expressing mice. Intravital TPLSM was performed by exteriorizing and fixing the liver lobe of living mice. This was repeated several times for the long-term imaging of the same mouse. Viable cancer cells in the living liver of living mice were visualized intravitally at a magnification of over 600×. Single cancer cells were arrested within hepatic sinusoids 2 h after injection. Platelet aggregation surrounding a cancer cell was observed, indicating a phenomenon of tumor-cell induced platelet aggregation. Cancer cells were extravasated from hepatic sinusoids to the space of Disse. Protrusions of Kupffer cells surrounding a cancer cell were observed, indicating that Kupffer cells appear to phagocytose cancer cells. SL4 cells formed liver metastatic colonies with extensive stromal reaction. Liver metastases by HT29 cells were observed as a cluster of micrometastatic nodules. High-resolution, dual-colored, real-time visualization of cancer metastasis using intravital TLPSM can help to understand spatiotemporal tumor-host interactions during metastatic processes in the living organs of living animals.  相似文献   
992.
This paper describes the field performance of air conditioning with an energy pile system, which was applied to the pile foundations of an actual building for the purpose of reducing the cost of the underground heat exchanger. First, the building for both office and residential use, for which a space heating and cooling system using friction piles was installed, was built in Sapporo in December 2000. Second, three tests were carried out to specify the design of a heat exchanger inside the pile, and a U-tube type underground heat exchanger was adopted from the viewpoint of energy efficiency and installation costs. Long-term space heating operation measurements indicated that the seasonal average temperatures of brine returning from the underground and pile surfaces were 2.4 and 6.7 °C, respectively. The average coefficient of performance for space heating was quite high at 3.9, and the seasonal primary energy reduction rate compared with a typical air conditioning system reached 23.2%.  相似文献   
993.
The effects of crystal textures and the potentials in the anodic oxidation of zirconium in a boiling nitric acid solution were investigated to study the stress corrosion cracking of zirconium in nitric acid solutions. The test specimen was machined such that the specimen surface was parallel to the rolling surface, arranged with a (0002) crystal texture. The potentials applied for the anodic oxidation of zirconium were set at 1.2, 1.4, and 1.5 V against a saturated KCl–Ag/AgCl electrode (SSE) in boiling 6 M HNO3. The growth of the zirconium oxide film dramatically changed depending on the applied potential at a closed depassivation potential (1.47 V vs. SSE in this study). At 1.5 V, the zirconium oxide film rapidly grows, and its growth exhibits cyclic oxidation kinetics in accordance with a nearly cubic rate law. The zirconium oxide film grows according to the quantity of electric charge and the growth rate does not depend on the crystal texture in the pretransition region before the cyclic oxidation kinetics. However, the growth and cracking under the thick oxide film depend on the crystal texture in the transition region. On the normal direction side, the oxide film thickness decreases on average since some areas of the thick oxide film are separated from the specimen surface owing to the cracks in the thick oxide. On the rolling direction (RD) side, no cracks in the thick oxide film are observed, but cracks are found under the thick oxide film, which deeply propagate in metal matrix along the RD without an external stress. The cracks under the thick oxide film propagate to the center of the oxide layer. The crystal orientation relationship between the oxide layer and the zirconium matrix is (0002)Zr//(111)ZrO2, and the cracks in the oxide layer propagate in the (0002)Zr plane in the zirconium matrix. The oxide layer consists of string-like zirconium oxide and zirconium hydride. The string-like zirconium oxide contains orthorhombic ZrO2 in addition to monoclinic ZrO2. It is not well known why the cracks propagate along the (0002)Zr plane under the thick oxide film. As one assumption for the mechanism of crack initiation and propagation without an external stress, it is considered that the oxidizing zirconium hydrides precipitated in the (0002)Zr plane near the interface of the thick oxide film and the matrix. Then, the phase transformation from orthorhombic ZrO2 to monoclinic ZrO2 in the oxide layer causes the crack propagation in the (0002) plane.  相似文献   
994.
An enzyme-linked immunosorbent assay (ELISA) was developed for the quantitative analysis of alkylphenol polyethoxylates (APnEOs) and their biodegradation products. To generate a specific monoclonal antibody (mAb) for the ELISA, hybridoma cells were produced by the fusion of mouse myeloma cells and spleen cells from mice immunized with nonylphenol polyethoxylate (NPnEO) derivatives coupled to bovine serum albumin. The developed ELISA showed the detection limits of 16 and 30 μg/L NP10EO when 10% and 60% (v/v) methanol solutions were used as assay diluent. The mAb was shown to be specific to APnEOs and their metabolites, such as short-ethoxy-chain APnEOs and alkylphenoxy carboxylic acids, except for nonylphenol. Moreover, no response was observed with non-APnEO surfactants as well as other compounds structurally similar to APnEOs. The percentage river water recoveries of 85–118% were obtained for 10 μg/L NP10EO fortification after preconcentration by C18 solid-phase extraction. The ELISA was also validated by comparing it with high-performance liquid chromatography for the analysis of APnEOs and their metabolites in river samples; the correlation coefficient between the values obtained by these assays was 0.96.  相似文献   
995.
 The Karvonen formula, which is widely used to estimate exercise intensity, contains maximum heart rate, HRmax, as a variable. This study employed pedaling experiments to assess which of the proposed formulas for calculating HRmax was the most suitable for use with the Karvonen formula. First, two kinds of experiments involving an ergometer were performed: an all-in-one-day experiment that tested eight pedaling loads in one day, and a one-load-per-day experiment that tested one load per day for eight days. A comparison of the data on 7 subjects showed that the all-in-one-day type of experiment was better for assessing HRmax formulas, at least for the load levels tested in our experiments. A statistical analysis of the experimental data on 47 subjects showed two of the HRmax formulas to be suitable for use in the Karvonen formula to estimate exercise intensity for males in their 20 s. In addition, the physical characteristics of a person having the greatest impact on exercise intensity were determined.  相似文献   
996.
Abstract— The technologies behind an in‐cell optical touch‐panel LCD with novel input functions will be described. By improving both the optical and electrical signal‐to‐noise ratio (SNR), a touch‐panel operation robust to ambient conditions can be achieved with a low‐power consumption suitable for integration into mobile products. The high SNR also enables a range of novel input functions making the in‐cell optical touch panel a promising platform for the next‐generation of user interface.  相似文献   
997.
We propose a simple method of simulating chemical reaction networks by using a multiset rewriting system: abstract rewriting system on multisets (ARMS). We simulate the oregonator model, a mathematical model of the Belousov-Zhabotinskii reaction, and we obtain the same behavior when the differential equations or the Gillespie method are used. We also compose a 1- and 2-dimensional cellular automata by using ARMS, and confirm that it shows the pattern forming that is observed in the BZ reaction. This work was presented in part at the First European Workshop on Artificial Life and Robotics, Vienna, Austria, July 12–13, 2007  相似文献   
998.
Abstract— An autostereoscopic 3‐D display suitable for the mobile environment is prototyped and evaluated. First, the required conditions for a 3‐D display in a mobile environment are considered, and the three major requirements are clarified: small size, viewing‐position flexibility, and application support. An application of a mobile‐type 3‐D display should be different from that of a large‐sized 3‐D display because a mobile‐type 3‐D display cannot realize the feeling of immersion while large‐sized 3‐D displays can realize it easily. From this assumption, it is considered that it is important to realize the feeling to handle a 3‐D image. Three types of 3‐D displays are developed to satisfy these requirements. They are subjectively evaluated to confirm their attractiveness. Results of the tests show that intuitive interaction can increase the reality of the 3‐D image in the sense of unity and also can improve the solidity and depth impression of the 3‐D image.  相似文献   
999.
A new efficient simulation smoother and disturbance smoother are introduced for asymmetric stochastic volatility models where there exists a correlation between today's return and tomorrow's volatility. The state vector is divided into several blocks where each block consists of many state variables. For each block, corresponding disturbances are sampled simultaneously from their conditional posterior distribution. The algorithm is based on the multivariate normal approximation of the conditional posterior density and exploits a conventional simulation smoother for a linear and Gaussian state-space model. The performance of our method is illustrated using two examples: (1) simple asymmetric stochastic volatility model and (2) asymmetric stochastic volatility model with state-dependent variances. The popular single move sampler which samples a state variable at a time is also conducted for comparison in the first example. It is shown that our proposed sampler produces considerable improvement in the mixing property of the Markov chain Monte Carlo chain.  相似文献   
1000.
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