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621.
Kobayashi M Otsuka K Tamura Y Tomizawa S Kamijo K Iwakoshi K Sato C Nagayama T Takano I 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2011,52(4):226-236
A simple and rapid method using GC-MS and GC-FPD for the determination of pesticide contamination in processed food has been developed. Pesticides were extracted from a sample with ethyl acetate in the presence of anhydrous sodium sulfate, then cleaned up with a combination of mini-columns, such as macroporous diatomaceous earth, C18, GCB (graphite carbon black) and PSA. Recovery tests of 57 pesticides (known to be toxic or harmful) from ten kinds of processed foods (butter, cheese, corned beef, dried shrimp, frozen Chinese dumplings, grilled eels, instant noodles, kimchi, retort-packed curry and wine) were performed, and the recovery rates were mostly between 70% and 120%. This method can be used to judge whether or not processed foods are contaminated with pesticides at potentially harmful levels. 相似文献
622.
Local anesthetics and antipsychotic phenothiazines cause a rapid shutdown of both actin polarization and translation initiation in yeast cells, like some environmental stresses. These compounds all have an amphiphilic structure, surfactant activity and the ability to lyse yeast cells. To elucidate the structures responsible for the shutdown activity and cell lysis, we investigated a variety of amphiphiles. In the hydrophobic region, the straight alkyl structure was sufficient for the shutdown of actin polarization and translational initiation. In the hydrophilic region of the straight alkyl compounds, cationic trimethyl ammonium (TMA) and non-ionic hydroxyl structure (alcohols) shut down both reactions, while an anionic structure, sulphate, with a long alkyl chain (≥C6) shut down actin polarization only. On the compounds that shut down both reactions, including the clinical drugs, TMA compounds and alcohols, the potencies of shutdown and lysis exponentially increased with increasing the number of carbons in the hydrophobic region, whereas safety was affected by the structures of both hydrophilic and hydrophobic regions. These results indicate that the yeast system can easily evaluate clinical drugs, and provide a structural basis for designing compounds to shut down intracellular reactions. 相似文献
623.
We focus on condensation and collapse processes of vapor bubble(s) in a subcooled pool. We generate the vapor in the vapor
generator and inject it/them to form vapor bubble(s) at a designated temperature into the liquid at a designated degree of
subcooling. In order to evaluate the effect of induced flow around the condensing/collapsing vapor bubble, two different boundary
conditions are employed; that is, the vapor is injected through the orifice and the tube. We also focus on interaction between/among
the condensing/collapsing vapor bubbles laterally injected to the pool. Through this system we try to simulate an interaction
between the vapor bubble and the subcooled bulk in a complex boiling phenomenon, especially that known as MEB (microbubble
emission boiling) in which a higher heat flux than critical heat flux (CHF) accompanying with emission of micrometer-scale
bubbles from the heated surface against the gravity is realized under a rather high subcooled condition. 相似文献
624.
Yuya Kasho Hidetoshi Hirai Masanori Tsukuda Ichiro Omura 《Microelectronics Reliability》2011,51(9-11):1689-1692
“Stealth” electric current probing technique for power electronics circuits, power device modules and chips makes it possible to measure electric current without any change or disassembling the circuit and the chip connection for the measurement. The technique consists of a tiny-scale magnetic-field coil, a high speed analog amplifier and a digitizer with numerical data processing. This technique can be applied to a single bonding wire current measurement inside IGBT modules, chip scale current redistribution measurement and current measurement for surface mount devices. The “stealth” current measurement can be utilized in the failure mechanism understanding of power devices including IGBT short circuit destruction. 相似文献
625.
Ultrafast Terahertz Gating of the Polarization and Giant Nonlinear Optical Response in BiFeO3 Thin Films 下载免费PDF全文
626.
We synthesized a conjugate in which gelatin was covalently crosslinked to agarose using 1,1-carbonyldiimidazole (CDI) in dimethyl sulfoxide in order to obtain gels with cellular adhesiveness that showed a sol-to-gel transition, but no gel-to-sol transition, around body temperature. The gelatin content of the conjugate increased by 2.7-fold when the concentration of CDI was increased from 1.3 to 32.7 mM. Aqueous solutions of the conjugate gelled upon cooling from 40 degrees C to 20 degrees C, but did not remelt at 37 degrees C. The percentage of adhered cells after 4 h of culture on a gel created from a conjugate containing about 25 wt% gelatin was similar to that for cells grown on tissue culture dishes. The adhered cells proliferated on the conjugate gel during culture for a further 5 d. In addition, the conjugate used in this study did not result in mechanical instability of the resultant gel compared to that of an unmodified agarose gel. These results demonstrate that this agarose-gelatin conjugate is a good candidate material for tissue engineering. 相似文献
627.
Tatsuro Shinchi Tetsuro Kitazoe Haruhiko Nishimura Masayoshi Tabuse Nobuyuki Azuma Ichiro Aoki 《Artificial Life and Robotics》2002,6(1-2):36-43
Fish schools behave like a single organism, and this offers considerable survival advantages. In our simulations, a fish school
is well organized, without a leader, and behaves like a single creature depending solely on the interactions among individuals.
This kind of system can be said to be typical of “complex systems.” In this article, it is shown that fractal evaluation is
useful to understand the features of fish school movements. We make clear the validity of fractal analyses to quantify fish
school movements through evaluations of simulated fish school movements andsardine movements. These fractal analyses show that we need two different fractal dimensions (D
1,D
2) to understand the features of fish school movements:D
1 corresponds to thesmaller coarsening levels, andD
2 corresponds to thelarge coarsening levels. The linear analyses in log-log space give an excellent fit with both the simulated movements and the sardine school movements.
In approaching complex systems or complex behaviors, fractal analyses have attracted wide attention in mathematics, physical
sciences, and information science. The fractal evaluations here convince us that we are coming close to understanding the
structure of complex movements of animals.
This work was presented, in part, at the Sixth International Symposium on Artificial Life and Robotics, Tokyo, Japan, January
15–17, 2001 相似文献
628.
Kazuya Nishina Shigeto Sudo Kazuyuki Yagi Tomohito Sano Yusuke Takata Hiroshi Obara Sadao Eguchi Noriko Oura Shinji Yano Satoru Ohkoshi Yutaka Fujita Yutaka Shiratori Masaki Tsuji Hiroyuki Hasukawa Yasufumi Suzue Yasunao Yamada Hiroyuki Mizukami Ichiro Uezono 《Nutrient Cycling in Agroecosystems》2015,103(1):87-99
629.
630.
We have been studying mesenchymal stem cells (MSCs) in synovial fluid and the intra-articular injection of synovial MSCs in osteoarthritis (OA) knees. Here, mainly based on our own findings, we overview the characteristics of endogenous MSCs in the synovial fluid of OA knees and their mode of action when injected exogenously into OA knees. Many MSCs similar to synovial MSCs were detected in the synovial fluid of human OA knees, and their number correlated with the radiological OA grade. Our suspended synovium culture model demonstrated the release of MSCs from the synovium through a medium into a non-contacting culture dish. In OA knees, endogenous MSCs possibly mobilize in a similar manner from the synovium through the synovial fluid and act protectively. However, the number of mobilized MSCs is limited; therefore, OA progresses in its natural course. Synovial MSC injections inhibited the progression of cartilage degeneration in a rat OA model. Injected synovial MSCs migrated into the synovium, maintained their MSC properties, and increased the gene expressions of TSG-6, PRG-4, and BMP-2. Exogenous synovial MSCs can promote anti-inflammation, lubrication, and cartilage matrix synthesis in OA knees. Based on our findings, we have initiated a human clinical study of synovial MSC injections in OA knees. 相似文献