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Pressure-sensitive paint (PSP) was applied to the surface of a NACA0012 airfoil to investigate pressure fluctuations associated with trailing edge (TE) noise under low-velocity flow conditions. The primary focus is to assess the feasibility of employing laser pulses exposed at the airfoil surface to mitigate TE noise. However, the weak pressure fluctuations accompanying TE noise pose a challenge, as they are overshadowed by image sensor noise in high-speed cameras capturing PSP emission changes. To address this issue, a novel time-resolved phase-locking technique was introduced, utilizing the signal from a semiconductor pressure transducer at the trailing edge as a phase-lock trigger source. By repetitively conducting phase-locked measurements (1150 times), time series ensemble averaged data based on PSP emission images were obtained, enabling the capture of these subtle pressure fluctuations. Quantitatively, fluctuations with a dominant frequency of 679 Hz and an amplitude of 50 Pa are resolved within an accuracy of about 15 Pa, achieved at a recording rate of 19.2 kHz. Both the suppression and subsequent redevelopment of the pressure field with the TE noise offer valuable insights into the dynamics of TE noise and open avenues for targeted noise reduction strategies in aerodynamic applications. [ABSTRACT FROM AUTHOR]

Aluminum oxide (Al2O3) films have been investigated for use in various applications, and numerous deposition techniques have been reported. The spray synthesis method has the advantage of forming a thin layer of crystal at low temperatures using the appropriate precursors. A precursor prepared by diluting Methylaluminoxane with N-methyl pyrrolidone was sprayed onto a porous membrane while varying conditions such as the substrate temperature, feeding speed, and spray amount. The solution penetrated the film during spray application, and the ultra-thin layers deposited on the side wall of the internal pores were observed using a cross-sectional transmission electron microscope (XTEM). The lattice image obtained using the TEM and the composition analysis conducted using a scanning TEM and an energy-dispersive X-ray spectroscope suggest that this thin layer is a layer of Al2O3. The formation of Al2O3 occurred at lower temperatures than in previous reports. This is a major advantage for applications with low-melting-point materials. The most suitable spraying conditions were determined based on the state of deposition on the surface and inside the membrane. These conditions were applied to a three-layer separator for lithium-ion batteries and their effect on thermal stability was investigated. Through heating experiments and XRD analysis, it was confirmed that the shrinkage and melting of the separator are suppressed by spraying. This process can be expected to have wide applications in low-melting-point materials such as polyolefin. [ABSTRACT FROM AUTHOR]

Non-doped ZnMgO thin film deposited at room temperature on a white glass using a diethylzinc-based solution grown by atmospheric conventional spin coating was annealed at 150°C. The sample had an average optical transmittance of more than 85% in the visible region, and a-axis orientation hexagonal polycrystal, a dense crystal, and a flat surface. Moreover, the n-type sample was obtained from the predominant zinc interstitial caused by x-ray photoemission spectroscopy. A sample had a resistivity of 14 × 106 Ω cm, carrier concentration of 3.9 × 1011 cm−3, and mobility of 5.0 cm2 (Vs)−1. [ABSTRACT FROM AUTHOR]

Depositions are conducted on monolayer porous membrane at 50 °C by spray pyrolysis using methylaluminoxanes diluted with N‐methylpyrrolidone. The solution penetrates the film during spraying and the ultra‐thin layers are deposited on the side wall of internal pores. It is suggested that these layers are fine polycrystalline of Al2O3. In the obtained film, most of the pores are exposed on the surface and there is no increase in film thickness. Further, the ionic conductivity is the same as that of the received film, and the thermal stability is improved. This method can be an effective technique for improving the function of the separator used in the lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Trailing-edge noise (TE noise) is an aeroacoustic sound radiated from an isolated airfoil in the specific ranges of low-speed flow. We used a pulsed laser as an actuator to reduce the TE noise without modifying the airfoil's surface. The wind tunnel test was conducted to verify the capability of an Nd:YAG laser as the actuator. The laser beam was focused into the air just outside the velocity boundary layer on the lower side of an NACA0012 airfoil. The experimental result shows that the TE noise is suppressed for a certain period after beam irradiations. We then analyzed the physical mechanism of the noise reduction with the laser actuation by the implicit large eddy simulation (ILES), a high-fidelity numerical method for computational fluid dynamics (CFD). The numerical investigations indicate that the pulsed energy deposition changes the unstable velocity amplification mode of the boundary layer, the source of an acoustic feedback loop radiating the TE noise, to another mode that does not generate the TE noise. The sound wave attenuation is observed once the induced velocity fluctuations and consequently generated vortices sweep out the flow structure of the unstable mode. We also examined the effect of the laser irradiation zone's shape by numerical simulations. The results show that the larger irradiation zone, which introduces the disturbances over a wider range in the span direction, is more effective in reducing the TE noise than the shorter focusing length with the same energies. [ABSTRACT FROM AUTHOR]

Combined measurement of shape and aerodynamic force is effective for understanding the mechanism of transonic wing flutter. To explore one method, a random-dot pressure-sensitive paint (PSP) was applied to the time-resolved global measurement of the deformation and pressure field of a transonic flow over an airfoil. The random-dot PSP has a patterned texture with luminescence intensity, which is made by intentional photodegradation of a PSP dye. These dots allow simultaneous measurement of pressure and the surface profile of the airfoil using stereo-digital image correlation. The feasibility of the random-dot PSP was tested in a transonic wind tunnel using a three-dimensional backswept wing model, which started to flutter at Mach 0.89 with a dominant frequency of 100 Hz. The unsteady surface profile and pressure distribution of the airfoil were measured using 12-bit high-speed cameras as the deformation amplitude increased. The experimental results indicate that the deformation and surface pressure distribution during flutter were successfully measured over time. The accuracy of the measured deformations and pressures was evaluated by comparison with several point data obtained with a laser displacement meter and semiconductor pressure transducers. The accuracy at each time-resolved image obtained at a recording rate of 6.25 kHz was within 1 mm for displacement and about 1 kPa for pressure. [ABSTRACT FROM AUTHOR]

Autonomous robots are expected to replace dangerous, dirty, and demanding (3D) jobs. At a theme park, surveillance, cleaning, and guiding tasks can be regarded as 3D jobs. The present paper attempts to develop an autonomous tour guide robot system and co-experience system at a large theme park. For realizing such autonomous service robots used in our daily environment, localization is one of the most important and fundamental functions. A number of localization techniques, including simultaneous localization and mapping, have been proposed. Although a global navigation satellite system (GNSS) is most commonly used in outdoor environments, its accuracy is approximately 10 m, which is inadequate for navigation of an autonomous service robot. Therefore, a GNSS is usually used together with other localization techniques, such as map matching or camera-based localization. In the present study, we adopt the quasi-zenith satellite system (QZSS), which became available in and around Japan in November 2018, for the localization of an autonomous service robot. The QZSS provides high-accuracy position information using quasi-zenith satellites (QZSs) and has a localization error of less than 10 centimeters. In the present paper, we compare the positioning performance of the QZSS and the real-time kinematic GPS and verify the stability and the accuracy of the QZSS in an outdoor environment. In addition, we introduce a tour guide robot system using the QZSS and present the results of a guided tour experiment in a theme park. On the other hand, based on the tour guide system, we also develop a co-experience robot system in a theme park, which realizes the sharing of experiences using an immersive VR display and the 5th-generation mobile communication system (5G). The robot is equipped with a 360-degree video camera and real-time 4K video is transmitted to a remote operator using the large communication capacity of the 5G network. The experimental results at a theme park showed that the guided tour experiment was successful and that the co-experience system allowed sharing of the experience with high immersion by a remote operator. [ABSTRACT FROM AUTHOR]

Chromophores composed of 4-cyano-5-dicyanomethylene-2-oxo-3-pyrroline (CDCOP) and a donor have been synthsized for electrooptic applications. Three substituents of [5-(4-aminophenyl)-2-thienyl]-substituted CDCOP 1 and (4-aminophenyl)-substituted CDCOP 2 were modified to suppress the aggregation for effective poling. To 1, bulky and branched 2-ethylhexyl groups were introduced instead of linear alkyl groups. Less aggregation was confirmed in the polymer dispersion films, and the corona poling behaviors were examined. To 2, we introduced norbornyl epoxide groups as bulky and thermally crosslinkable moieties. The aggregation was suppressed as well, and the thermal crosslinking of the epoxide with acid anhydride in the presence of a base was investigated. [ABSTRACT FROM AUTHOR]

Non‐doped ZnO thin films are deposited on glass by spray pyrolysis using Diethylzinc diluted with diisopropyl ether. The droplet impacts are observed and the structural properties of films are studied as deposition temperature dependence. The shape of a droplet impacts changes from a hemisphere to a flat plane with increasing the deposition temperature. The images of cross sectional transmittance electron microscopy show granular non‐crystalline for RT (room temperature) sample and columnar polycrystalline for 150 °C sample as shown on the right‐side. The growth mechanism of ZnO thin films is discussed by considering the relationship between the shape of droplet impacts and the morphology of the deposited films. Also, the presence of the crystal formed by precursor is suggested for the films deposited at lower temperature. [ABSTRACT FROM AUTHOR]

A multicenter, open-label, dose-escalation phase 1/2 study was undertaken to evaluate the optimal subcutaneous tocilizumab dose that would result in exposure comparable to the intravenous tocilizumab 8-mg/kg approved dose in patients with rheumatoid arthritis. A pharmacokinetic and biomarker approach was used to estimate the clinical optimal dose regimen of subcutaneous tocilizumab. Safety and efficacy of subcutaneous tocilizumab were assessed as secondary end points. Patients received subcutaneous tocilizumab at 81 mg every 2 weeks (q2w) (n = 8), 162 mg q2w (n = 12), or 162 mg weekly (qw) (n = 12) for 24 weeks. 88% of 162-mg q2w patients and 100% of 162-mg qw patients maintained mean serum trough tocilizumab concentrations of ≥1 µg/mL, and had exposure comparable with the approved intravenous tocilizumab dose of 8 mg/kg; this resulted in normalized C-reactive protein levels and improvement in ACR20/50/70 responses. The most common adverse events were abnormal laboratory results, which were mild in severity. Anti-tocilizumab antibodies were detected in a few patients in the 81-mg q2w and 162-mg qw groups. In conclusion, coupled with efficacy and tolerability results, the appropriate dose of subcutaneous tocilizumab was determined to be 162 mg q2w for Japanese patients. [ABSTRACT FROM AUTHOR]

Liver ischemia reperfusion injury is associated with both local damage to the hepatic vasculature and systemic inflammatory responses. CD39 is the dominant vascular endothelial cell ectonucleotidase and rapidly hydrolyses both adenosine triphosphate (ATP) and adenosine diphosphate to adenosine monophosphate. These biochemical properties, in tandem with 5′-nucleotidases, generate adenosine and potentially illicit inflammatory vascular responses and thrombosis. We have evaluated the role of CD39 in total hepatic ischemia reperfusion injury (IRI). Wildtype mice, Cd39-hemizygous mice (+/−) and matched Cd39-null mice (−/−); ( n = 25 per group) underwent 45 min of total warm ischemia with full inflow occlusion necessitating partial hepatectomy. Soluble nucleoside triphosphate diphosphohydrolase (NTPDases) or adenosine/amrinone were administered to wildtype ( n = 6) and Cd39-null mice ( n = 6) in order to study protective effects in vivo. Parameters of liver injury, systemic inflammation, hepatic ATP determinations by P-NMR and parameters of lung injury were obtained. All wildtype mice survived up to 7 days with minimal biochemical disturbances and minor evidence for injury. In contrast, 64% of Cd39+/− and 84% of Cd39-null mice required euthanasia or died within 4 h post-reperfusion with liver damage and systemic inflammation associated with hypercytokinemia. Hepatic ATP depletion was pronounced in Cd39-null mice posthepatic IRI. Soluble NTPDase or adenosine administration protected Cd39-deficient mice from acute reperfusion injury. We conclude that CD39 is protective in hepatic IRI preventing local injury and systemic inflammation in an adenosine dependent manner. Our data indicate that vascular CD39 expression has an essential protective role in hepatic IRI. [ABSTRACT FROM AUTHOR]

Degradation of fast response pressure-sensitive paints (PSP) above room temperature is a serious problem for PSP measurements in high-temperature environments. A standard polymer-ceramic PSP (PC-PSP) composed of platinum(II)-5,10,15,20-tetrakis-(2,3,4,5,6-pentafluorphenyl)-porphyrin (PtTFPP), titania particles and poly(isobutyl methacrylate) (polyIBM) was characterized to elucidate the degradation mechanism. Applying a two-gate lifetime-based method, the PC-PSP has sufficient pressure and temperature sensitivities even at 100 °C, while the luminescence intensity significantly decreases during the test. Subsequent measurements on thermal and photostability as well as luminescence spectra reveal that the main cause of the degradation is the photodegradation of PtTFPP due to direct exposure of the dye molecules to the atmosphere. In order to suppress such degradation, a small amount of urethane resin is added to the dye solution as a simple additional step in the preparation of PC-PSP. The addition of the urethane resin significantly reduces the degradation of the PSP, although its time response is slightly slower than that of the standard PC-PSP. [ABSTRACT FROM AUTHOR]

OBJECTIVE--Extracellular nucleotides are important mediators of inflammatory responses and could also impact metabolic homeostasis. Type 2 purinergic (P2) receptors bind extracellular nucleotides and are expressed by major peripheral tissues responsible for glucose homeostasis. CD39/ENTPD1 is the dominant vascular and immune cell ectoenzyme that hydrolyzes extracellular nucleotides to regulate purinergic signaling. RESEARCH DESIGN AND METHODS--We have studied Cd39/Entpd1-null mice to determine whether any associated changes in extracellular nucleotide concentrations influence glucose homeostasis. RESULTS--Cd39/Entpd1-null mice have impaired glucose tolerance and decreased insulin sensitivity with significantly higher plasma insulin levels. Hyperinsulinemic-euglycemic clamp studies indicate altered hepatic glucose metabolism. These effects are mimicked in vivo by injection into wild-type mice of either exogenous ATP or an ecto-ATPase inhibitor, ARL-67156, and by exposure of hepatocytes to extracellular nucleotides in vitro. Increased serum interleukin-1Β, interleukin-6, interferon-Γ and tumor necrosis factor-α levels are observed in Cd39/Entpd1-null mice in keeping with a proinflammatory phenotype. Impaired insulin sensitivity is accompanied by increased activation of hepatic c-Jun NH2-terminal kinase/ stress-activated protein kinase in Cd39/Entpd1 mice after injection of ATP in vivo. This results in decreased tyrosine phosphorylation of insulin receptor substrate-2 with impeded insulin signaling. CONCLUSIONS--CD39/Entpd1 is a modulator of extracellular nucleotide signaling and also influences metabolism. Deletion of Cd39/Entpd1 both directly and indirectly impacts insulin regulation and hepatic glucose metabolism. Extracellular nucleotides serve as "metabolokines," indicating further links between inflammation and associated metabolic derangements. Diabetes 57:2311-2320, 2008 [ABSTRACT FROM AUTHOR]

CD39, or vascular adenosine triphosphate diphosphohydrolase, has been considered an important inhibitor of platelet activation. Unexpectedly, cd39-deficient mice had prolonged bleeding times with minimally perturbed coagulation parameters. Platelet interactions with injured mesenteric vasculature were considerably reduced in vivo and purified mutant platelets failed to aggregate to standard agonists in vitro. This platelet hypofunction was reversible and associated with purinergic type P2Y1 receptor desensitization. In keeping with deficient vascular protective mechanisms, fibrin deposition was found at multiple organ sites in cd39-deficient mice and in transplanted cardiac grafts. Our data indicate a dual role for adenosine triphosphate diphosphohydrolase in modulating hemostasis and thrombotic reactions. [ABSTRACT FROM AUTHOR]

Growth striations in Czochralski-grown Si wafers have been observed by a scanning x-ray double-crystal method. We confirmed that the striations on the topographs relate to the variation of oxygen concentration. [ABSTRACT FROM AUTHOR]

This paper reports the relationship between oxygen concentration and dislocation multiplication in silicon crystals during directional solidification using numerical analysis. Based on the Alexander–Haasen–Sumino model, this analysis involved oxygen diffusion from the bulk to dislocation cores during crystal growth and annealing processes in a furnace. The results showed that the dislocation density mainly increased during cooling process, rather than crystal growth, when the effect of oxygen diffusion to dislocation cores was ignored. On the contrary, the dislocation density increased during both crystal growth and cooling processes when the effect of interstitial oxygen diffusion was considered. At a dislocation density larger than 1.0 × 105 cm−2, the interstitial oxygen concentration in bulk decreased due to the diffusion process, if interstitial oxygen atoms were between dislocations, whereas the concentration at dislocation cores increases. [ABSTRACT FROM AUTHOR]

We report on a patient with colon cancer and a very high serum α-fetoprotein level. This 75-yr-old man presented with right lower quadrant abdominal pain. An abdominal CT scan as well as ultrasonography showed a tumor in the cecum. Serum α-fetoprotein level was extremely high (3,070 ng/ml). At laparotomy, a large was found in the cecum, and a right hemicolectomy was performed. Histological examination, including immunohistochemical study, showed an adenocarcinoma of the colon producing α-fetoprotein. [ABSTRACT FROM AUTHOR]

Nanoaggregates of three butadiyne derivatives, i.e., butadiyne derivatives with one tetrathiafulvalene (TTF) moiety at one end (BUT1), two TTF moieties at both ends (BUT2), and one TTF moiety directly bound to the butadiyne group (TBU), and their charge-transfer (CT) complexes with 2,5-difluoro-7,7,8,8-tetracyanoquinodimethane (F2TCNQ) were prepared by the reprecipitation method. The nanoaggregate sizes of BUT1, BUT2, and TBU were about 80–200 nm and those of the CT complexes were reduced to about 100 nm. Upon UV irradiation, nanoaggregates of BUT1 showed regular 1,4-addition polymerization in the solid state while those of BUT2 and TBU polymerized in an irregular manner. However, solid-state polymerization of their CT complexes was not confirmed and decomposition of the complexes was observed. From the X-ray study, the crystallinity of the nanoaggregates was found to degrade in general, compared with that of the corresponding bulk crystals. Interestingly, nanoaggregates of BUT1-F2TCNQ and BUT2-F2TCNQ complexes were found to have conductivities of more than 10−6 S/cm, although their bulk crystals did not show measurable conductivities. [ABSTRACT FROM AUTHOR]

We propose a simplified reaction model for SiGe epitaxial growth by chemical vapor deposition (CVD). The SiH4 and GeH4 adsorption at vacant sites, the exchange reaction between SiH and GeH at the surface, and the decomposition of SiH and GeH are considered in the model. The decomposition of SiH4 or GeH4 into SiH2 or GeH2 is representative of complicated reactions in the gas phase. SiGe growth is carried out on a 300 mm Si substrate by reduced-pressure CVD from the SiH4–GeH4–H2 system in the original epitaxial furnace. The dependences of the growth rate and Ge content in the SiGe layer on the temperature and GeH4 flow rate are determined by the characterization of specimens cut from certain positions in 300 mm wafers. By using the chemical reaction analysis software package chemkin, the rate constants in the proposed model are determined by comparison with experimental results. In this report, we validate that the model can explain the behavior of SiGe CVD. [ABSTRACT FROM AUTHOR]