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[ABSTRACT] The energy band structure provides crucial information on charge transport behaviour in organic semiconductors, such as effective mass, transfer integrals, and electron-phonon coupling. Despite the discovery of the valence (the highest occupied molecular orbital (HOMO)) band structure in 1990s, the conduction band (the lowest unoccupied molecular orbital (LUMO)) has not been experimentally observed. In this work, we employ angle-resolved low-energy inverse photoelectron spectroscopy to reveal the LUMO band structure of pentacene, a prototypical high-mobility organic semiconductor. The derived transfer integrals and bandwidths from the LUMO are substantially smaller than those predicted by density functional theory calculations. To reproduce this bandwidth reduction, we propose an improved (partially dressed) polaron model that accounts for the electron-intramolecular vibrational interaction with frequency-dependent coupling constants based on Debye relaxation. This model quantitatively reproduces not only the transfer integrals, but also the temperature-dependent HOMO and LUMO bandwidths, and the hole and electron mobilities. The present results demonstrate that electron mobility in high mobility organic semiconductors is indeed limited by polaron formation.

Cyclosporin A (CyA) has potent inhibitory activity on organic anion transporting polypeptide 1B (OATP1B), causing drug-drug interactions with its substrate drugs. 3-carboxy-4-methyl-5-propyl-2-furanpropionate (CMPF), a uraemic toxin, has also been suggested to inhibit OATP1B activity. Recent study has identified coproporphyrin-I (CP-I) as a specific endogenous substrate for OATP1B, which is useful to indicate OATP1B activity. We investigated the relationship of CP-I with CyA and CMPF concentrations in patients taking CyA.In total, 121 blood samples from 74 patients who took CyA and underwent routine therapeutic drug monitoring were divided into trough and peak samples.CyA and CP-I concentrations were significantly higher in peak samples than in trough samples. A positive correlation between CP-I and CyA concentrations was found in all samples and in trough and peak samples, while no correlation was observed between CP-I and CMPF concentrations. Multiple regression analysis identified CyA and C-reactive protein concentrations as independent factors affecting CP-I concentration, with blood CyA concentration having markedly greater contribution to plasma CP-I concentration.The present study suggests that CyA inhibits OATP1B activity in a concentration-dependent manner in clinical setting, and that dose adjustment of OATP1B substrate drugs coadministered with CyA according to plasma CMPF concentration may not be necessary.

The conduction band dispersion in methylammonium lead iodide (CH3NH3PbI3) was studied by both angle-resolved two-photon photoelectron spectroscopy (AR-2PPE) with low photon intensity (∼0.0125 nJ/pulse) and angle-resolved low-energy inverse photoelectron spectroscopy (AR-LEIPS). Clear energy dispersion of the conduction band along the Γ-M direction was first observed by these independent methods under different temperatures, and the dispersion was found to be consistent with band calculation under the cubic phase. The effective mass of the electrons at the Γ point was estimated to be (0.20 ± 0.05)m0 at the temperature of 90 K. The observed conduction band energy was different between the AR-LEIPS and AR-2PPE, which was ascribed to the electronic-correlation-dependent difference of initial and final states probing processes. The present results also indicate that the surface structure in CH3NH3PbI3 provides the cubic-dominated electronic property even at lower temperatures.

A possibility of developing an environmental-friendly photovoltaic/thermal (PV/T) solar panel, which can shut high temperature radiation within a panel box, was experimentally confirmed. The panel has a decompression-boiling heat collector, which can absorb heat from the PV module and can keep the air and the cover glass inside the panel box at lower temperature by using lower boiling temperature of working fluid under vacuum condition. The panel also has an emboss-processed cover glass, which can totally reflect the high temperature heat radiation from the PV module within the panel box. The experimental results using a single PV/T system showed that it could keep the heat radiation temperature from the PV/T solar panel surface around 45 °C even in summer; it provided the hot water at least 60 °C by controlling the flow-rate; and it produced 71.3% of solar energy in total as electricity and 40 °C heat, in summer, Yokohama, Japan. Highly efficient utilization of solar energy with small environmental heat-load would be possible by using the proposed PV/T system.

Indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid are uremic toxins that accumulate in renal failure and have been reported to decrease the activities of the drug-metabolizing enzyme cytochrome P450 3A and the drug transporter organic anion transporting polypeptides 1B, respectively. In this study, we established and validated an assay for simultaneous quantification of indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid in human plasma. The samples were pretreated by solid-phase extraction, and measured by ultra-high-performance liquid chromatography-tandem mass spectrometry. The validation results for this assay were within the acceptable limits recommended by the US Food and Drug Administration, with a lower limit of quantitation of 0.05 μg/mL for both indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid. Recovery rates of indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid corrected by internal standard were 100.7-101.9 and 100.2-101.3%, respectively. Matrix effects of indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid corrected by internal standard were 101.1-105.5 and 97.0-103.8%, respectively. The validated assay was used to analyze indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid concentrations in the plasma samples of healthy volunteers and patients with chronic kidney disease. All the measured plasma indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid concentrations were within the calibration ranges. This novel method may contribute to predicting the activities of drug-metabolizing enzymes and drug transporters in individual patients.

The conduction band dispersion in methylammonium lead iodide (CH

AlSi10Mg alloy, processed by selective laser melting (SLM) in as-built state and gravity casting in solution-treated state, was heat-treated at several temperatures for different durations, and the resulting dimensional changes were investigated. For the cast AlSi10Mg alloy, the linear dimensional change heat-treated at 200 ˚C was approximately 0.10%, which agreed with that calculated by a theoretical model. The linear dimensional change of the SLM AlSi10Mg alloy heat-treated at 150 ˚C was 0.17%. This indicated that, in as-built state, the concentration of supersaturated solid solution Si in α-Al phase was 1.7 wt% on average, and the lattice constant of α-Al phase was 0.4047 nm. SLM AlSi10Mg alloy contained more than 3 cm3/100 g-Al hydrogen and showed a linear dimensional change of more than 0.6% after the heat treatment at 530 ˚C because of porosity expansion. The relative densities of the SLM AlSi10Mg alloy heat-treated at 150 ˚C for 1800 ks and 530 ˚C for 18 ks were 99.89% and 98.12%, respectively.

To elucidate the growth, a kind of non-reversible dimensional change occurring in heat treatments or long-term services, of AlSi10Mg alloy products fabricated by selective laser melting (SLM), the dimensional and microstructural changes arising from a heat treatment at 423 K for 1800 ks were investigated. In as-built state, there were no Si precipitates in the α-Al cells near the top of the specimen and the concentration of the solid solution Si in the α-Al phase was higher than 1.6 wt%. However, some of the supersaturated solid solution Si in the α-Al phase near the bottom of the specimen precipitated during SLM processing. After the heat treatment, the Si precipitates increased in number and coarsened, and the concentration of the solid solution Si in α-Al cells almost became zero. The linear dimensional change arising from the heat treatment was 0.17%, which was much higher than that of gravity cast AlSi10Mg alloy. This linear dimensional change occurred mainly due to the precipitation of the supersaturated solid solution Si in the α-Al phase.

A non-syndromic, congenital bifid tongue is an extremely rare malformation, the details of which are largely unknown. A female neonate was referred to our division presenting with a bifid tongue. The cleft was located in the right anterior part of the tongue. In addition, 2 tumors (10 mm and 2 mm) were located at the base of the cleft. Seven days after birth, the tumors were excised and primary closure of the cleft was performed for correction of the bifid tongue. The postoperative course was uneventful, and follow-up examination 20 months later showed no functional disturbance. Furthermore, all published cases were carefully reviewed to improve our understanding of the etiology of congenital bifid tongue. Formation of a congenital neoplasm during the early stages of tongue development could be the main etiology of a bifid tongue.

Intraosseous lymphoma in the maxilla or mandible is sometimes difficult to diagnose because of the absence of specific signs and symptoms. This study reports five cases of intraosseous lymphoma in the oral and maxillofacial regions. There were four cases of diffuse large B-cell lymphoma (DLBCL), including EBV-positive DLBCL of the elderly, and one of Burkitt's lymphoma. Regarding the tumor sites, three of the cases were in the maxilla, while two were in the mandible. Two of the conditions were clinically diagnosed as inflammatory diseases at the time of their first examination. Two patients died of their lymphoma during the follow-up period. Based on these events and findings, we clearly realized that careful examination is necessary to be diagnosed early, which results in a much better prognosis. Moreover, maxillofacial surgeons need to keep following up carefully on their patients to immediately recognize any recurrences after completion of treatment.

Isobaric heat capacity of liquid 1,1,1,3,3-pentafluoropropane (R245fa) was measured. Since our group constructed a flow-calorimeter in 1985, specific isobaric heat capacity of liquid refrigerants have been measured for R32, R123, R125, R134a, R142b, and R152a. In 2014, the authors modified the apparatus of flow calorimetry with an improvement for achieving a stable mass-flow-rate by introducing plastic accumulators and two parallel needle valves. The apparatus is able to measure isobaric heat capacity with unmeasurable level small heat loss and good repeatability mostly within 0.4 % (80 % of the data) and the largest 1.5 % from the maximum scatter. The measurements were obtained at 15 points of state parameters, along two pressures of 500 kPa and 800 kPa in a temperature range from 278 K to 343 K. The expanded uncertainty (coverage factor of k = 2) for the heat capacity value is predicted for each datum as being between 0.36 and 1.12 %. The purity of the sample liquid R245fa is analyzed as being better th...

An experimental ischemia (EI)-induced mouse model was used to analyze pathological and biochemical alterations in testes. Initial morphological changes were observed in Sertoli cells of EI testes at the light microscopic level. Examination of the ultrastructure using transmission electron microscopy confirmed that Sertoli cells were partially detached from the basement membrane of the seminiferous epithelium and that the cell membranes of adjacent Sertoli cells were not joined. The functional integrity of the blood-testis barrier (BTB) was assessed using the lanthanum tracer technique. Lanthanum had penetrated into the spaces between adjacent Sertoli cells in the adluminal compartment up to the lumen of the seminiferous epithelium in EI testes. Proteome analysis showed that the expression of heat shock protein (HSP) 70 was significantly upregulated in EI testes. Western blot analysis confirmed that the expression of HSP70 increased in a time-dependent manner after the EI procedure. HSP70 immunostaining was observed in spermatocytes and in round and elongated spermatids in EI testes. Our results suggest that a change in the junctions between adjacent Sertoli cells on the basal compartment is involved in the BTB disruption in EI testes. Therefore, male infertility caused by the BTB disruption could be associated with heat stress induced by ischemia.

A precise determination of the critical temperature and density for technically important fluids would be possible on the basis of the digital image for the visual observation of the phase boundary in the vicinity of the critical point since the sensitivity and resolution are higher than those of naked eyes. In addition, the digital image can avoid the personal uncertainty of an observer. A strong density gradient occurs in a sample cell at the critical point due to gravity. It was carefully assessed to determine the critical density, where the density profile in the sample cell can be observed from the luminance profile of a digital image. The density-gradient profile becomes symmetric at the critical point. One of the best fluids, whose thermodynamic properties have been measured with the highest reliability among technically important fluids, would be carbon dioxide. In order to confirm the reliability of the proposed method, the critical temperature and density of carbon dioxide were determined using the digital image. The critical temperature and density values of carbon dioxide are ( $$304.143\,\pm \,0.005)\hbox { K}$$ and ( $$467.7\,\pm \,0.6)$$ kg $$\cdot $$ m $$^{-3}$$ , respectively. The critical temperature and density values agree with the existing best values within estimated uncertainties. The reliability of the method was confirmed. The critical pressure, 7.3795 MPa, corresponding to the determined critical temperature of 304.143 K is also proposed. A new set of parameters for the vapor-pressure equation is also provided.

Ejector refrigeration cycle is a simple system, which can provide cooling by using solar thermal energy. Instead of a mechanical compressor of refrigeration cycle, refrigerant in evaporator is evacuated by an ejector using supersonic flow generated by the vapor pressure at temperatures being higher than around 60 °C. The ejector configuration design is a key to get a high efficiency of the cycle. In order to realize the behavior of the refrigerant in ejector, computational fluid dynamics (CFD) is applied to get the best geometry parameters, and then the parameters are confirmed by experimental trials. The CFD is developed as an in-house solver of the compressible Navier-Stokes equations. Through the numerical and experimental approach, four sets of configuration parameters of a mixing section area and a nozzle exit area of the ejector are being considered. A conclusion is that an appropriate mixing section area can make the greater cooling capacity but the condensing temperature decreases, while a smaller nozzle exit area can avoid the energy loss of shockwave that makes reliable repeatability and higher condensing temperature but lower cooling capacity in our experimental trials. The performances of ejector cycles having four different sets of configuration parameters cannot exceed a linear relationship between cooling capacity and condenser temperature so far. This paper reports an up-to-date result for developing an appropriate design method of ejector configuration.

Improving performance of existing air-conditioning system and minimizing its environmental effect are requested from global environmental issues. A new air-conditioning system using evapo-transpiration condenser has been proposed. Evapo-transpiration condenser is a condenser that uses transpiration by keeping condenser surface wet and water evaporation enhancing heat-transfer rate. In this paper, a prototype of the new system is tested and compared with the existing system in summer weather of Japan. Hourly-average condenser-temperature is achieved to be 5–10 °C reduction compared to that of the air-cooled condenser. Without any optimization in system operation, up to more than 30% hourly integral power consumption is saved at ambient temperature below 31 °C from this prototype. Besides, temperature of outlet-air from outdoor-unit is nearly the same as ambient temperature, while its relative humidity is slightly higher. Special maintenance is not necessary for the new evapo-transpiration condenser.

Air-conditioning (AC) system consumes high energy and releases waste-heat. In the present study, we propose a method to improve its performance and minimize waste-heat by replacing existing air-cooled condenser by an evaporation and transpiration, evapo-transpiration, condenser. The improvement is confirmed by performing experiment for a conventional air-cooled AC system and a water-cooled AC system. Condenser temperature in the air-cooled system is higher than outdoor-temperature by 5–10 °C, while it is −5 to 5 °C in case of the testing system. From simulation results, saving energy consumption is expected to reach up to 30% in summer with the testing system. Based on these results, an evapo-transpiration heat-exchanger was developed as a new condenser. Heat-transfer coefficient of the testing heat-exchanger is at least 4 times higher than that of air-cooled condenser. Even hot fluid is used inside copper-tubing, its outlet-air temperature is as nearly as outdoor temperature.

Specific heat capacities at a constant pressure of liquid ethanol in a temperature range from (265 to 348) K at a pressure of 500 kPa were measured by using flow calorimetry. The expanded uncertainty evaluated is from (0.55 to 0.89) % including the repeatability. Existing measurements by other researchers and derived specific heat capacity values from the existing equation of state provide greater values beyond the uncertainty. To confirm the reliability of our measurements, we measured the heat capacities under the same conditions for different liquid ethanol samples provided from different manufacturers. The measurements almost perfectly agree each other. The measurements obtained for two different samples of liquid ethanol are reported.