79 research outputs found

    On-site analysis for nitrogen oxides using a newly developed portable flow injection analyzer

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    A new portable flow injection system was developed for on-site chemical analysis, which allows the rapid analysis of aqueous samples at sampling sites. The system comprises a newly designed double-plunger micro pump, a six-way sample injector, a reaction coil in a thermostated compartment and a detector. All of these units are connected with 0.5 mmi.d. PTFE tubing. A visible detector is assembled using a maximum wavelength of 525 nm of a light-emitting diode (LED) and 540 nm of an interference filter. The system is of the one-box type, whose dimensions are 160(W) x 160(H) x 320(D) mm, and is easy to carry to the analysis site; the weight is 8 kg. A thermostated compartment is incorporated into the proposed system in order to be used outdoors, where temperatures are changeable. The system can workwith DC 12Vas well as AC 100V; therefore, a car battery or a portable battery can be used as the power source. The analytical data can be memorized in IC cards or a note-book personal computer connected with a RS232C cable. Furthermore, software on the market can be easily used. By using the proposed system, the on-site determination of nitrogen oxides, such as nitrate and nitrite, could be carried out. Calibration graphs for nitrate and nitrite ions were linear over ranges of 0 to 1.0ppm and 0 to 100ppb ofN-NOs and N-NO2 with good precision; the sampling rate was 40~50 samples per hour. The detection limit for N-NO3 and N-NO2 was 0.5 ppb. By using the proposed system, the on-site determination of nitrate and nitrite in river water samples was carried out. The relative standard deviations of ten injections were 0.65% for nitrate and 0.15% for nitrite. Furthermore, nitrate and nitrite in biological samples as a metabolic products of nitric oxide, which have attracted a lot of attension as a messenger of diverse physiological processes, were also determined on-site with high sensitivity. By using a car battery as a power source, the proposed system worked continuously. In addition, it worked for about 5 hours continuously with a portable battery.試料採取現場での迅速な分析,すなわちオンサイト分析のための新しいポータブルフローインジェクション分析計の開発を行った・このFIA装置では,160×160誉320(mm)の箱の中にダブルプランジ ャーマイクロポンプ,試料注入語検出器及び反応恒温槽を組み入れ,重量8kgと小型・軽量化を達成し,持ち運び容易な分析計とした.特に,525nmの発光ダイオード(LED)を光源とする新規検出 器を開発することにより,小型,省電力化が可能となった.温度変化の大きな屋外での測定に耐えられるように,反応恒温槽も装備した.本FIA装置は交流100Vでのほか,直流12Vでも稼働し,カーバ ッテリーや市販のポータブルバッテリーを電源とするオンサイト分析に対応できるよう設計した.カーバッテリーを電源とした場合は長時間の連続運転が可能である.測定データはメモリーカードや RS232Cによりノート型パーソナルコンピュータへの通信も可能で,更に市販の表計算ソフトを利用してデータ処理が可能である.本装置を窒素酸化物のオンサイト分析に応用した.硝酸,亜硝酸イオン標準液による検量線は,0~1・Oppm,0~100ppbの範囲で直線性,再現性共に良好で,1時間当たり40~50試料の分析が可能であった・検出限界(5/Ⅳ=3)は硝酸,亜硝酸態窒素として0.5ppbと通常のFIAシステムを用いる場合と全く変わらない優れた性能を有することが分かった.河川水中の硝酸,亜硝酸イオンのオンサイト分析では10回の繰り返し測定における相対標準偏差は0.65%及び0.15%と良好な結果が得られた.また,血清中の一酸化窒素(NO)の酸化代謝物としての硝酸,亜硝酸イオン濃度のオンサイト分析を行い,良好な結果を得た.本研究で検討したポータブルバッテリーでは1回の充電で5時間の連続運転が可能であった

    Metalloproteinase regulation improves in vitro generation of efficacious platelets from mouse embryonic stem cells

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    Embryonic stem cells (ESCs) could potentially compensate for the lack of blood platelets available for use in transfusions. Here, we describe a new method for generating mouse ESC-derived platelets (ESPs) that can contribute to hemostasis in vivo. Flow cytometric sorting of cells from embryoid bodies on day 6 demonstrated that c-Kit+ integrin αIIb (αIIb)+ cells, but not CD31+ cells or vascular endothelial cadherin+ cells, are capable of megakaryopoiesis and the release of platelet-like structures by day 12. αIIbβ3-expressing ESPs exhibited ectodomain shedding of glycoprotein (GP)Ibα, GPV, and GPVI, but not αIIbβ3 or GPIbβ. ESPs showed impaired αIIbβ3 activation and integrin-mediated actin reorganization, critical events for normal platelet function. However, the administration of metalloproteinase inhibitors GM6001 or TAPI-1 during differentiation increased the expression of GPIbα, improving both thrombogenesis in vitro and posttransfusion recovery in vivo. Thus, the regulation of metalloproteinases in culture could be useful for obtaining high-quality, efficacious ESPs as an alternative platelet source for transfusions

    Effects of inorganic mercury and methylmercury on osteoclasts and osteoblasts in the scales of the marine teleost as a model system of bone

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    To evaluate the effects of inorganic mercury (InHg) and methylmercury (MeHg) on bone metabolism in a marine teleost, the activity of tartrate-resistant acid phosphatase (TRAP) and alkaline phosphatase (ALP) as indicators of such activity in osteoclasts and osteoblasts, respectively, were examined in scales of nibbler fish (Girella punctata). We found several lines of scales with nearly the same TRAP and ALP activity levels. Using these scales, we evaluated the influence of InHg and MeHg. TRAP activity in the scales treated with InHg (10-5 and 10-4 M) and MeHg (10-6 to 10-4 M) during 6 hrs of incubation decreased significantly. In contrast, ALP activity decreased after exposure to InHg (10-5 and 10-4 M) and MeHg (10-6 to 10-4 M) for 18 and 36 hrs, although its activity did not change after 6 hrs of incubation. As in enzyme activity 6 hrs after incubation, mRNA expression of TRAP (osteoclastic marker) decreased significantly with InHg and MeHg treatment, while that of collagen (osteoblastic marker) did not change significantly. At 6 hrs after incubation, the mRNA expression of metallothionein, which is a metal-binding protein in osteoblasts, was significantly increased following treatment with InHg or MeHg, suggesting that it may be involved in the protection of osteoblasts against mercury exposure up to 6 hrs after incubation. To our knowledge, this is the first report of the effects of mercury on osteoclasts and osteoblasts using marine teleost scale as a model system of bone. © 2014 Zoological Society of Japan

    Digital cities 6 : concepts, methods and systems of urban informatics (Workshop)

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    Exploring key challenges of urban informatics research and development, this workshop looks at concepts, research methods and instruments that become the microscope of urban anatomy. We want to discuss urban informatics systems that provide real-time tools for examining the real-time city, to picture the invisible and to zoom into a fine-grained resolution of urban environments that reveal the depth and contextual nuances of urban metabolism processes at work

    Learning From Humans: Agent Modeling With Individual Human Behaviors

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    Multiagent-based simulation (MABS) is a very active interdisciplinary area bridging multiagent research and social science. The key technology to conduct truly useful MABS is agent modeling for reproducing realistic behaviors. In order to make agent models realistic, it seems natural to learn from human behavior in the real world. The challenge presented in this paper is to obtain an individual behavior model by using participatory modeling in the traffic domain. We show a methodology that can elicit prior knowledge for explaining human driving behavior in specific environments, and then construct a driving behavior model based on the set of prior knowledge. In the real world, human drivers often perform unintentional actions, and occasionally, they have no logical reason for their actions. In these cases, we cannot rely on prior knowledge to explain them. We are forced to construct a behavior model with an insufficient amount of knowledge to reproduce the driving behavior. To construct such individual driving behavior model, we take the approach of using knowledge from others to complement the lack of knowledge from the target. To clarify that the behavior model including prior knowledge from others offers individuality in driving behavior, we experimentally confirm that the driving behaviors reproduced by the hybrid model correlate reasonably well with human behavior

    An Auction-Based Negotiation Protocol for Agents with Nonlinear Utility Functions

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