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This study proposes a straight-bladed vertical-axis turbine for ocean-wave energy conversion. The aim is to develop a novel air turbine suitable for an oscillating water column in a wave energy plant. To this end, the performances of straight-bladed vertical-axis turbines were investigated for different guide-vane geometries in a wind tunnel experiment. The rotor has four straight blades with an NACA0018 profile, a chord length of 80.5 mm, a pitch diameter of 460 mm, and a blade width of 490 mm. In this study, the guide-vane geometry was varied as arc, semi-arc, and semi-arc with a straight part. Under steady flow conditions, the turbine performance was evaluated by determining the torque, input and flow coefficients, and the turbine efficiency. The semi-arc blade geometry decreased the input coefficient and increased the torque coefficient. Moreover, the semi-arc blade with a straight part improved the starting characteristics of the turbine and its efficiency over a wide range of flow coefficients.

Light transmission aggregometry (LTA) is the gold standard method for assessing platelet function. Recently, a new parameter called adenosine diphosphate (ADP)-induced platelet aggregation level (APAL) was developed to aid interpretation of LTA results. APAL is a score calculated based on platelet aggregation patterns upon exposure to 1 μM and 10 μM ADP and is determined using an automated coagulation analyzer. We compared APAL and VerifyNow P2Y42 patients who have received antiplatelet therapy were studied. Platelet function tests were performed on CS-2400 for APAL and VerifyNow P2YModerate correlations were observed between APAL and PRU (r=0.64,The APAL system exhibits moderate correlation with PRU and % inhibition. APAL testing is a good choice for a clinical laboratory already in possession of Sysmex CS series analyzers. In this setting, APAL testing can significantly decrease the cost of platelet function testing for patients on antiplatelet therapy.

BACKGROUND Light transmission aggregometry (LTA) is the gold standard for platelet function assessment. The automated coagulation analyzer from Sysmex that performs LTA offers the advantage of being a walk-away technology. Recently, a new parameter "ADP-induced platelet aggregation level (APAL)" was developed to support the interpretation of results. APAL is calculated as a score from 0.0 to 10.0 based on platelet aggregation patterns with 1 and 10 µM adenosine diphosphate (ADP). Here, the basic performance of the newly developed APAL system and comparison with the maximum aggregation rate of ADP (ADP-MA) was evaluated. METHODS The within-run precision was calculated by conducting five replicate analyses of the platelet-rich plasma (PRP) from healthy volunteers and 0.05 µM of cangrelor-spiked PRP. Cangrelor is a P2Y12 inhibitor that does not require liver CYP activation. The reference interval was calculated from the results of 67 healthy volunteers. The effect of the antiplatelet P2Y12 agent was evaluated using several concentrations of cangrelor. A comparative study was performed using 103 PRP samples with different levels of aggregation. Each test was analyzed with both APAL and ADP-MA. RESULTS The percentage coefficient of variation in within-run precision was within 7% for APAL and 10 µM ADP-MA. Reference interval of APAL and 10 µM ADP-MA was 7.1 - 10.0 and 80.0 - 99.2%, respectively. APAL signifi-cantly decreased with the addition of 0.02 µM cangrelor, while 10 µM ADP-MA was barely affected. A significant correlation was observed between APAL and 10 µM ADP-MA (r = 0.94; p < 0.0001). CONCLUSIONS The newly developed APAL system exhibited an acceptable performance. APAL score showed a good correlation with ADP-MA and was adequate to detect the weak effect of P2Y12 inhibitors. APAL is a new platelet aggregation scoring system with the potential to monitor the effects of P2Y12 inhibitor over a wide range.

We investigate the propagation of light in an ultra-thin gap in stacked-stripe three-dimensional (3D) photonic crystals operating in the near-infrared wavelength range. We fabricate 3D photonic crystals composed of 32 stacked layers with an artificially introduced gap (∼200 nm) in the center of the structure by using a wafer bonding method. In order to study the characteristics of the gap, we introduce oblique waveguides to connect the gap with the upper and lower sides of the photonic crystal. The observation of light output from waveguides that are distant from the waveguide used for incident light demonstrates for the first time that light propagates along the air gap and is distributed to multiple output waveguides. Moreover, we perform calculations that reveal the formation of a propagation mode resulting from introduction of the ultra-thin gap. We analyze the coupling between the propagation mode and the oblique waveguide mode and discuss the characteristics of light distribution via the gap.

Analysis of hand motions is crucial in such actual conditions as daily life and traditional work. We developed a measurement system using inertial sensors instead of an optical motion capture system that measures with spatial constraints. However, for these sensors, the posture error caused by the integration of the angular velocity is critical. A typical solution uses sensor fusion with simple observation equations to measure such lower limbs by walking analysis. For finger motions, a simple observation, calculated identically as the initial posture, is unsuitable because fingers may be moved intricately and quickly by multiple joints and parallel links. Therefore, we constructed an observation equation based on such dynamic acceleration as rotational acceleration and the correction of compass error. Using this suggested observation equation, since both the posture and position error were verified in the hand and forearm motions by a comparison with the optical motion capture, we could measure them with high accuracy. After measuring the movements of an actual hand, such as writing words and spinning a top, we analyzed the characteristics from a reproduced link model and joint angles.

In this study, we evaluated the degradation mechanism in quantum dot light-emitting diodes (QLEDs) to improve the device lifetime. We measured the hole mobility using the delay time of transient electroluminescence for three types of hole transport layer (HTL) materials. In addition, we estimated the degradation of luminance efficiency and hole mobility under constant current drive. As a result, the HTL material with a higher hole mobility yielded longer QLED device lifetimes. Through substitution of the HTL material from poly (9-vinylcarbazole) (PVK) to poly [(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4′-(N-(4-sec-butylphenyl)diphenylamine)] (TFB), the hole mobility and the 95% luminance lifetime from initial luminance improved from 0.5 × 10−5 cm2/V⋅s and 2.90 h at J = 10 mA/cm2 to 1.1 × 10−5 cm2/V⋅s and 179 h, respectively. Moreover, we clarified that the degradation of the luminescent efficiency is correlated with the hole mobility.

When we applied colloidal quantum dots (QDs) for quantum dot light emitting diodes, it was well known that shell thickness played an important role in core protection, confinement of electrons and holes, and charge injection efficiency. However, although the shell thickness dependence of electroluminescence properties was reported, carrier injection efficiency has not been discussed in detail. In this paper, we investigated the effect of shell thickness on the carrier injection efficiency that was evaluated by photoelectrochemical measurements. By comparing the product of internal quantum yield of photoluminescence and the evaluated carrier injection efficiency with external quantum efficiency (EQE) for QDs with various shell thicknesses, we found that the optimal shell thickness for increasing EQE is determined by the balance between protection of QD's surface and carrier injection efficiency.

The authors developed a wearable finger motion measurement system using inertial and geomagnetic sensors. Using this system, motion and posture of the hands and fingers can be measured. However, the joint center and segment axis cannot be accurately measured in a previous study using the sensors. Therefore, the authors proposed a method of estimating the joint center and segment lengths. This method utilizes the fact that the calculation formula of the rotational acceleration in the sensor's coordinate system is the vector product. However, because the vector product is irreversible, the rotation center was calculated by using a position vector placed on an intersection line of two planes constituted by rotational acceleration. As a result of the verification, estimation error was small. In addition, finger motion was measured using posture measurement and rotation center estimation. This measured motion, joint angle and segment lengths estimated by the finger motion measurement system were compared with a motion capture system. As a result, the initial MP and PIP joint angles had some differences, but there was no difference for the MP and PIP joint angles during movement and the other joint angles. Therefore, we need to improve the estimation method of the PIP and DIP joint centers.

An oblique waveguide in a stripe-stacked three-dimensional photonic crystal is a useful structure for interlayer coupling, but has a problem that the out-coupling to free-space is inclined and spatially asymmetric. We propose a new end structure that provides vertical and less-frequency-dependent out-coupling characteristics.

We investigate the radiation angle of an oblique waveguide in a stripe-stacked three-dimensional photonic crystal. We show that the output-light is radiated in a different direction from the oblique waveguide direction. Moreover, the radiation polar angle varies from 30° to 50° depending on the frequency. To inhibit the frequency dependence and obtain vertical radiation, we introduced a symmetric structure at the end of the waveguide. As a result of cancellation of the in-plane asymmetric wavenumber, the radiation polar angle is less than 6° from the surface-normal direction and does not depend on frequency.

As treatment for subluxation due to rheumatoid arthritis (RA), rehabilitation by hand therapy is one option, but the number of therapist is not sufficient. Therefore, a device for rehabilitation of thumb metacarpophalangeal (MP) joint subluxation has been developed. To improve the device, it is necessary to measure in close proximity to the actual rehabilitation. Therefore, the authors tried to measure two kinds of rehabilitation by using motion capture and a contact force sensor. To measure rehabilitation movements, three markers were attached to the metacarpal bone, six markers were attached to each side of the interphalangeal (IP) joint, MP joint and proximal phalanx of the right thumb of the subjects, and a finger model was created by these markers. Further, three markers were placed on the left index of the therapist, and force direction was calculated by these markers. Measurement was conducted on healthy subjects, Rehabilitation was performed by the person who is not a therapist, but received the guidance of the doctor who is coauthor. As a result, the authors could measure rehabilitation by hand therapy, force, point of action and displacement. The results suggest that rehabilitation with traction twice as efficient as that without traction. Furthermore, it was found that rehabilitation is possible with calculated force, and the force is reproducible by the actuator in the device.

ディーゼルエソジンの排出ガスに含まれる粒子状物質 (パティキュレート: PM) の触媒による燃焼除去を試みた. 種々の酸化物を担持した酸化チタン (y) 触媒で行ったところ, 銅触媒がPM燃焼に対し高活性を示し, 特に塩化銅 (IV) から調製した触媒 (Cu/TiO2(Cl)) が有効であることが判明した. さらに, 塩化物から調製した他の触媒の活性も確認され, 塩素の共存がPM燃焼に重要であることが示唆された. X線回折の結果, 銅触媒のみハロゲン化水酸化物〔塩化水酸化銅 (II) (CuCl (OH)) 〕の生成が確認され, 塩素の活性点形成への寄与が明らかとなり, この構造が酸素の活性化の促進に寄与していると推定される. またこの触媒は, 模擬排ガス条件でも有効に作用し, NOx, SOxの活性への影響は少なかった. 反応機構については, PMの触媒燃焼がすす (soot) の外側に存在する有機物質 (SOF) の有無に影響されないこと, sootが無定型炭素状であることから, 反応は固一固反応で進行し, そのため, 触媒で活性化された酸素種のPMへの移動がかぎであると考えられる. この活性な酸素種が塩素の存在によって生成することから, 銅触媒のような塩素種を含む構造の生成が触媒を調製する上で重要となる.

The partial reduction of nitriles with several alkylboranes produced an addition product, N-boryl imine, which was readily converted to secondary carbinamine by treatment with organolithium or Grignard reagents. Optically active N-boryl imines were also prepared from chiral borane and nitrile for the chiral amine synthesis.