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High-power light-curing units have emerged that reduce the time of procedures in dental clinical work. However, patients sometimes complain of pain during the polymerization of composite resin. In this experiment, we investigated how differences in light-curing mode affect the temperature rise during composite resin polymerization in vitro. Light-curing mode conditions were divided into four groups: 3 s in plasma mode (Plm3) and 5, 10, and 20 s in standard mode. The temperature curve under Plm3 exhibited a rapid increase during the first 3 s of light curing before reaching a maximum of around 55°C. In contrast, the temperature rose rapidly but less sharply for irradiation in each standard mode compared with Plm3. These results suggest that irradiation using a high-power mode increases the temperature at an excessively high rate, and this may raise concern about side effects on the pulp.

Using ferronickel slag as heat storage medium, low cost solid sensible heat storage system for concentrating solar thermal power generation plant has been considered. Effects of ferronickel slag mix on amount of heat storage of mortar block specimen using ferronickel slag as a fine aggregate are evaluated. It has been shown that amount of heat storage increases as volume fraction of ferronickel slag increases in heat storage test. On the other hand, it has been shown that variation of amount of heat storage with volume fraction of ferronickel slag differs between numerical results in steady state and those in unsteady state in numerical calculations based on theoretical analysis. The reason is explained by variations of specific heat capacity and thermal conductivity in the block with volume fraction of ferronickel slag. Variation of amount of heat storage in the block in unsteady state with volume fraction of ferronickel slag has been clarified.

Purpose Immersion tests in purified water were conducted to evaluate the leaching behaviors of filler elements contained in computer-aided design/computer-aided manufacturing (CAD/CAM) composite resin. Methods Four commercial CAD/CAM resin composite blanks were tested: Shofu block HC 2 layer, Cerasmart, Katana Avencia block, and KZR-CAD HR Block 2. The specimens in the size of 10.0 × 12.0 × 2.0 mm were immersed in a 50-mL conical tube containing 40 mL of purified water, and then placed in a constant-temperature oven set at a temperature of 37, 60, 70, or 80° C and stored statically for 30 days. After storage, the concentrations of leached elements in the immersion solution were measured with an inductively coupled plasma atomic emission spectrometer. To characterize the surface of the specimen after the immersion test, secondary electron images were obtained. Results The immersion test resulted in the leaching of Si, the main component, from all materials tested. Some materials were found to have leached high amount of Ba or Sr in addition to Si, and remarkable surface degradation was observed. The amount of leached elements increased with increased immersion temperatures. Conclusions Filler elements in CAD/CAM composite resins used in this study leached into purified water. The leached elements and its quantities greatly differed among materials and depend on the types of the oxides composing the filler. The amounts of leached elements varied in a temperature-dependent manner.

We recently reported that TAK-593, a novel imidazo[1,2-b]pyridazine derivative, is a highly potent and selective inhibitor of the vascular endothelial growth factor (VEGF) and platelet derived growth factor (PDGF) receptor tyrosine kinase families. Moreover, TAK-593 exhibits a uniquely long-acting inhibitory profile towards VEGF receptor 2 (VEGFR2) and PDGF receptor β (PDGFRβ). In this study, we demonstrated that TAK-593 potently inhibits VEGF- and PDGF-stimulated cellular phosphorylation and proliferation of human umbilical vein endothelial cells and human coronary artery smooth muscle cells. TAK-593 also potently inhibits VEGF-induced tube formation of endothelial cells co-cultured with fibroblasts. Oral administration of TAK-593 exhibited strong anti-tumor effects against various human cancer xenografts along with good tolerability despite a low level of plasma exposure. Even after the blood and tissue concentrations of TAK-593 decreased below the detectable limit, a pharmacodynamic marker (phospho VEGFR2) was almost completely suppressed, indicating that its long duration of enzyme inhibition might contribute to the potent activity of TAK-593. Immunohistochemical staining indicated that TAK-593 showed anti-proliferative and pro-apoptotic effects on tumors along with a decrease of vessel density and inhibition of pericyte recruitment to microvessels in vivo. Furthermore, dynamic contrast-enhanced magnetic resonance imaging revealed that TAK-593 reduced tumor vessel permeability prior to the onset of anti-tumor activity. In conclusion, TAK-593 is an extremely potent VEGFR/PDGFR kinase inhibitor whose potent anti-angiogenic activity suggests therapeutic potential for the treatment of solid tumors.

The present study intends to evaluate heat conductance and mechanical strength at elevated temperature of a prototype of flat type receiver composed of carbon steel fin and copper tubes. Considering a compound circular plate composed of different kinds of material layers as an analytical model of the receiver, a mathematical analysis of plane axisymmetric transient heat conduction and thermal stresses for the plate is developed. Performing numerical calculation for a compound circular plate consisted of carbon steel layer and copper one, the effect of thickness of copper layer on spatial variations and time-evolutions of temperature change and thermal stresses is discussed briefly.

We recently reported that compound 20d (comp.20d), a novel pyrrolo[3, 2‐d]pyrimidine derivative, is a potent and selective inhibitor of tumor angiogenesis‐related kinases, including vascular endothelial growth factor receptor (VEGFR) and platelet‐derived growth factor receptor (PDGFR). In this study, we show that comp.20d potently blocks the VEGF‐ and PDGF‐stimulated cellular phosphorylation (IC(50) = 2.5 and 3.6 nM, respectively) and proliferation of HUVECs and human coronary artery smooth muscle cells with IC(50) values of 2.8 and 9.6 nM, respectively, and potently inhibits the VEGF‐induced tube formation of endothelial cells cocultured with fibroblasts (IC(50) = 3.3 nM). Given orally twice daily, comp.20d at the doses of 1.5–6 mg/kg showed antitumor effects in mice bearing various human cancer xenografts. Consistent with the anti‐angiogenic mechanism of action, histological examination of tumors from comp. 20d‐treated mice indicated a decrease in microvessel density and inhibition of pericyte recruitment to microvessels, and these were concomitant with decreased interstitial fluid pressure that allowed for therapeutic intratumoral uptake of CPT‐11 (irinotecan hydrochloride). In conclusion, comp.20d is an extremely potent inhibitor of VEGFR/PDGFR kinases whose activities suggest therapeutic potential for the treatment of solid tumors that rely on angiogenesis for their survival. (Cancer Sci 2012; 103: 939–944)

It is important to measure heat flux from the burnt gas to the combustion chamber because of the improvement of the efficiency of an engine. Instantaneous heat flux of S. I. Engine is usually measured using a thin film type of heat flux sensor. But there is a significant difference of outputs among heat flux sensors on the market. In this study, some types of heat flux sensors are produced and evaluated by experiments using a constant volume vessel. To confirm the accuracy of each type of sensor, the wall side heat flux which is average of heat fluxes from same type of heat flux sensors installed in the vessel, is compared with the gas side heat flux which is calculated from the change of pressure in the combustion vessel. The results show that the wall side heat fluxes obtained by sensors which produced obeying the law of thermocouple are agree with the gas side heat flux. It is found that the plating film should be the same metal to the wire of sensor. Furthermore, measuring for the transient component of the heat flux, it is not necessarily for the body of a heat flux sensor to use the same material of the combustion wall.

Laser Doppler Velocimeter (LDV) is one of the most useful method to measure the flow velocity of fluid flow such as swirl velocity in an engine. The laser as the light source of LDV has been usually used high power gas laser because of the weak scattering light from particles as in case of back scattered LDV system or loss of light through the optical fibers. In recent years, laser diode of rather high power output and holding coherency was developed. Suggestion of using laser diode as the light source of LDV was shown, but the ability of its utility has not been clearly examined. In this paper, laser diode was examined to use the light source of LDV and was confirmed to be valid when it was correctly controlled. As the proof of validity of laser diode system, measured examples of mean velocity and turbulence intensity were shown in an engine.

Improving combustion of the spark ignition engines contributes largely to decreasing fuel consumption, especially under the conditions of medium or low speed and low load. In this paper, valve timing is evaluated from the viewpoints of swirl velocity as well as the volumetric efficiency, burned gas fraction in a fresh mixture charge, and pumping loss at intake stroke by using the predictions of the simplified simulation model. As a result, the timing of intake valve opening and closing is considerably affected by the swirl velocity. It is also confirmed that the mean swirl velocity controlled by the valve timing is higher than that controlled by the conventional throttling system under the same volumetric efficiency condition.

銀-マンガン複合酸化物触媒を用いて,クロトンアルデヒドの液相水素化反応を行い,触媒の熱処理による結晶状態と活性,2ヴテン-1-オール選択率との関係について検討した。触媒は所定量の硝酸銀と硝酸マンガンの混合溶液と水酸化ナトリウム水溶液から共沈法により調製した。500℃ 焼成触媒で活性(反応率)851%,選択率71.8%が得られた。触媒を250℃ で焼成すると,銀と酸化マンガンの酸化還元反応により,活性に有効な無定形のAg20が生成する。反応に有効な400～500℃ 焼成触媒はAg20(無定形),MnO,(無定形),γ-Mn203(結晶性)から構成される。反応時の活性は調製時に存在する無定形のAg20の分散度や結晶状態に影響される。活性種はAgであり,酸化マンガンの共存は触媒表面の銀粒子の分散度を高め,Ag2OのAg結晶への低温還元を抑制し,高い活性と選択率を示す銀を生成させると考えられる。

アルミナーリン酸アルミニウム担持銀触媒とマンガソ添加触媒を用いて,クロトンアルデヒドの液相水素化反応を行い,反応率とtrans-2-ブテン-1-オール選択率との関係について調べた。本触媒は,リソ酸・硝酸アルミニウム混合溶液とアンモニナ水から得たゲル状沈殿物に金属硝酸盗を含浸する方法により調製した.触媒の担体組成比P/A1(原子比)を大にすると,AIPO4の結晶化が起とり,生成した旅ρπ5-2一ブテンー1一オールの0部が脱水素反応によりクロトンアルデヒドを生じ,原料が増加して反応率が低下する。選択率は,P/Al=0.8までほぼ一定となり,P/Al=1・0でAg3PO4の結晶化にともない低下する・マンガソ添加銀触媒では,反応率r選択率ともに増加し,Mn/Ag(原子比)=1.5以上で,ブテソ4-オ-ル収率は70.5xnal%となり,マソガン未添加触媒を用いた場合の36.6mo1%と2-くらべていちじるしく高くなった。マンガン添湘銀触媒は,クロトンアルデヒドの炭素一炭素二重結合の水素化を搾葡して,ブチルアルデヒドの生成率を減少させ,同時に2-ブテン-1-オールの一部脱水素反応も抑制する距め,2-プテン1-オール収率が向上すると考えられる。

Serum human parathyroid hormone (1-34)[hPTH(1-34)] levels and the anabolic effect of hPTH(1-34) were compared after administration using multiple pulses of iontophoresis or subcutaneous (sc) intermittent injections to ovariectomized (OVX) Sprague Dawley rats. Triple-pulse iontophoretic administration of hPTH(1-34) (doses: 40-400 microg/patch), achieved by repeated 30-min applications of a 0.1 mA/cm(2) current separated by 45-min rest intervals, produced three sharp peaks in the serum hPTH(1-34) level in response to application of the current. Each peak appeared at the end of the 30-min current application period and was proportional to the hPTH(1-34) dose. Compared with once-daily sc injections (7 pulses/week), triple-pulses iontophoretic administered 3 times/week (9 pulses/week) for 4 weeks produced dose-related increases in the bone mineral density (BMD) of the distal 1/3 femur. For the sc administration, the relative BMD values using the vehicle injection as a reference standard for 1, 5, and 25 microg/kg/day were 104, 114, and 121%, respectively. For iontophoretic administration, the relative BMD values using the placebo patch as a reference standard for 40, 120, and 400 microg/patch were 104, 110, and 116%, respectively. The increase in the BMD plotted against the area under the hPTH(1-34) serum level-time curve (AUC) over 1 week resulted in similar straight lines in the 9 pulses/week iontophoretic administration and the 7 pulses/week sc administration groups. The estimated iontophoretic dose giving an equivalent BMD to once-daily sc administration at 5 microg/kg/day was 120 microg/patch. These findings strongly suggest that three iontophoretic pulses administered on alternate days will exert an anabolic effect equivalent to that of daily sc administration at doses giving the same weekly AUC. Furthermore, this method of administering hPTH(1-34) might enable self-medication, a useful advance in the treatment of osteoporosis.

Vapor-phase hydrogen transfer reaction between acrolein and 2-propanol over MgO catalyst systems has investigated. We found that, particularly at early reaction time, both the high activity and remarkable increase of allyl alcohol selectivity were achieved by the addition of a small amount of MgCl2 on MgO catalyst.

The activity and selectivity of Ag-MnO2/Al2O3·5AlPO4 catalysts for the hydrogenation of crotonaldehyde to crotyl alcohol have been investigated in liquid phase. When MnO2 was added to the catalyst, the activity and selectivity for the reaction were remarkably improved to give the conversion of 100 mol% and the selectivity of 69.5%.

A Raney-type silver-zinc (1:1 wt. ratio) catalyst was found to exhibit a high activity and selectivity for the hydrogenation of acrolein to allyl alcohol, 70% conversion and 90% selectivity being observed in 90 min at 120 °C. Addition of small amount of Fe3+ to the catalyst resulted in an increase in the selectivity to 95% with a slight decrease in activity.

A two-step thermochemical water splitting cycle using nonstoichiometric cerium oxide is a promising solar thermochemical hydrogen production process. One of the present authors has developed new solar reactors using “internally circulating fluidized beds” with cerium oxide particles for the high-temperature cycle. These solar reactors need to be combined with a beam-down solar concentrating system. Niigata University, University of Miyazaki, and Mitaka Kohki Co. Ltd. recently started an R&D joint project to demonstrate the up-scaled fluidized bed reactors with solar. A new type of 100 kWth beam-down solar concentrating system was built in August, 2012 at the campus of University of Miyazaki. This paper describes the first results of solar flux measurements on the new Miyazaki beam-down system for demonstration of thermochemical water splitting reactors. The fluxes of concentrated solar radiation at the focus point were measured by moving an array of thirteen Gardon gauges. The solar power in an area of 130 × 130 cm in the focal spot was larger than 90 kWth during three hours of daytime radiation, exceeding 110 kWth around noon on October 12, 2012. A new CPC specific to this new beam-down system was designed and fabricated to concentrate the solar fluxes into a 44 cm diameter circle of the solar reactor aperture. The solar demonstration of the reactors will start at the Miyazaki beam-down system from October 2013.

Five kinds of iron oxide catalysts promoted with sulfur were prepared by impregnating Fe(OH)3 with (NH4)2SO4 and by treating Fe2O3 and Fe(OH)3 with H2S and SO2. Changes in acidic properties of the catalysts with changes in oxidation states of sulfur were investigated by test reactions such as isomerization of cyclopropane and dehydration of 2-propanol over the oxidized or reduced catalysts. It has been found that the generation of acidic properties of the catalysts was independent of the kinds of the starting sulfur compounds, but dependent on the oxidation states of the sulfur. The sulfur in the highest oxidation state was responsible for the strongly acidic property of the catalyst.

The activity and selectivity of Ag-MnO2/Al2O3·5AlPO4 catalysts for the hydrogenation of crotonaldehyde to crotyl alcohol have been investigated in liquid phase. When MnO2 was added to the catalyst, the activity and selectivity for the reaction were remarkably improved to give the conversion of 100 mol% and the selectivity of 69.5%.

Five kinds of iron oxide catalysts promoted with sulfur were prepared by impregnating Fe(OH)3 with (NH4)2SO4 and by treating Fe2O3 and Fe(OH)3 with H2S and SO2. Changes in acidic properties of the catalysts with changes in oxidation states of sulfur were investigated by test reactions such as isomerization of cyclopropane and dehydration of 2-propanol over the oxidized or reduced catalysts. It has been found that the generation of acidic properties of the catalysts was independent of the kinds of the starting sulfur compounds, but dependent on the oxidation states of the sulfur. The sulfur in the highest oxidation state was responsible for the strongly acidic property of the catalyst.