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We previously reported that high concentrations (≥3.42 mM) of calcium during in vitro fertilization (IVF) disturbed the extrusion of the second polar body (PBII) in C3H/He inbred mice. In this study, the substrain specificity of this phenomenon was examined under 1.71–6.84 mM calcium concentration in ova from six C3H/He mouse commercially available substrains in Japan. PBII extrusion in ova from J substrains was not affected by calcium concentrations (<10% at any calcium level), but was grossly disturbed at high calcium levels in the ova of other substrains. This result has practical applications for the efficient production of normal zygotes by IVF, therefore contributing to the reduction in the numbers of donor animals for further zygote or embryo manipulation. Care must be taken in choosing IVF medium for particular strains and substrains.
This study evaluated the relationship between radiation and Eustachian tube dysfunction, and examined the radiation dose required to induce otitis media with effusion.
The function of 36 Eustachian tubes in 18 patients with head and neck cancer were examined sonotubometrically before, during, and 1, 2 and 3 months after, intensity-modulated radiotherapy. Patients with an increase of 5 dB or less in sound pressure level (dB) during swallowing were categorised as being in the dysfunction group. Additionally, radiation dose distributions were assessed in all Eustachian tubes using three dose–volume histogram parameters.
Twenty-two of 25 normally functioning Eustachian tubes before radiotherapy (88.0 per cent) shifted to the dysfunction group after therapy. All ears that developed otitis media with effusion belonged to the dysfunction group. The radiation dose threshold evaluation revealed that ears with otitis media with effusion received significantly higher doses to the Eustachian tubes.
The results indicate a relationship between radiation dose and Eustachian tube dysfunction and otitis media with effusion.
Public stigma alters attitudes towards people with mental illness, and is a particular concern for young people since most mental health problems occur in adolescence and young adulthood. However, little is known about the long-term effects of repeated filmed social contact (FSC) on reducing mental health-related stigma among young adults in the general population, compared with self-instructional Internet search (INS) and control interventions.
This study is a parallel-group randomised controlled trial over 12 months conducted in Tokyo, Japan. A total of 259 university students (male n = 150, mean age = 20.0 years, s.d. = 1.2) were recruited from 20 colleges and universities between November 2013 and July 2014, without being provided information about the mental health-related survey or trial. Participants were assigned to one of three groups before completion of the baseline survey (FSC/INS/control = 89/83/87). The FSC group received a computer-based 30-min social contact film with general mental health education and five follow-up web-based FSCs at 2-month intervals. The INS group undertook a 30-min search for mental health-related information with five follow-up web-based reminders for self-instructional searches at 2-month intervals. The control group played PC games and had no follow-up intervention. The main outcome measures were the future (intended behaviour) domain of the Reported and Intended Behaviour Scale at 12 months after the intervention. Analysis was conducted in September 2015.
At the 12-month follow-up, 218 participants completed the survey (84.1%, 75:70:73). The FSC group showed the greatest change at the 12-month follow-up (FSC: mean change 2.11 [95% CI 1.49, 2.73], INS: 1.04 [0.29, 1.80], control: 0.71 [0.09, 1.33]; FSC v. INS p = 0.037, FSC v. controls p = 0.004). No adverse events were reported during the follow-up period.
FSC was more successful in reducing stigma at 12 months after intervention than INS or control interventions. FSC could be used to reduce stigma in educational lectures and anti-stigma campaigns targeted at young people.
This study is registered at UMIN-CTR (No. UMIN000012239).
A balloon-borne X-ray instrument with the modulation collimator was designed and constructed to study the structure of solar X-ray flares. The angular resolution was approximately one arc minute. The instrument was used on an occasion of X-ray flare on Sept. 27, 1970.
We have conducted 1.1 mm ALMA observations of a contiguous 105” × 50” or 1.5 arcmin2 window in the SXDF-UDS-CANDELS. We achieved a 5σ sensitivity of 0.28 mJy, giving a flat sensus of dusty star-forming galaxies with LIR ~6×1011L⊙ (if Tdust=40K) up to z ~ 10 thanks to the negative K-correction at this wavelength. We detected 5 brightest sources (S/N>6) and 18 low-significant sources (5>S/N>4; they may contain spurious detections, though). One of the 5 brightest ALMA sources (S1.1mm = 0.84 ± 0.09 mJy) is extremely faint in the WFC3 and VLT/HAWK-I images, demonstrating that a contiguous ALMA imaging survey uncovers a faint dust-obscured population invisible in the deep optical/near-infrared surveys. We find a possible [CII]-line emitter at z=5.955 or a low-z CO emitting galaxy within the field, allowing us to constrain the [CII] and/or CO luminosity functions across the history of the universe.
There is an increased need for highly sensitive imaging devices to develop high resolution and high speed image sensors. Incident light intensity per pixel of image sensors is getting lower because the pixel resolution and frame rate of image sensors are becoming higher. We investigated the feasibility of using a photoconductor with tin-doped gallium oxide (Ga2O3:Sn)/Cu(In,Ga)Se2 (CIGS) hetero-junction for visible light image sensors. CIGS chalcopyrite thin films have great potential for improving the sensitivity of image sensors and CIGS chalcopyrite semiconductors have both a high absorption coefficient and high quantum efficiency. Moreover, the band gap can be adjusted for visible light. We applied Ga2O3 as an n-type semiconductor layer and a hole-blocking layer to CIGS thin film to reduce the dark current. The experimental results revealed that dark current was drastically reduced due to the application of Ga2O3 thin film, and an avalanche multiplication phenomenon was observed at an applied voltage of over 6 V. However, non-doped Ga2O3/CIGS hetero-junction only had sensitivity in the ultraviolet light region because their depletion region was almost completely spread throughout the Ga2O3 layer due to the low carrier density of the Ga2O3 layer. Therefore, we used Ga2O3:Sn for the n-type layer to increase carrier density. As a result, the depletion region shifted to the CIGS film and the cells had sensitivity in all visible regions. These results indicate that Ga2O3:Sn/CIGS hetero-junction are feasible for visible light photoconductors.
Nitinol was coated with biocompatible calcium phosphate materials by pulsed electrolytic deposition (ELD) to reduce toxic metal-ions elution. The pulse ELD for the stents was carried out with changing the current off-periods (toff) of the pulse wave. The pulse ELD suppressed the generation of H2 gas due to the electrolysis of water on a calcium phosphate layer and improved the adhesiveness of the coating layer on nitinol compared with a conventional DC-ELD. The coating layers were identified to be octacalcium phosphate (OCP) at lower toff, while they were transformed to dicalcium phosphate anhydraous (DCPA) with an increase of toff. The layers of OCP or DCPA on the nitinol surface were subjected to a NaOH treatment at 60°C for 3days to transform them into hydroxyapatite (HAp). From results of a metal-ions elution test, the deposited calcium phosphates suppressed nickel ions elution at one quarter compared with the bare nitinol stent. These results indicate that the pulse ELD of biocompatible calcium phosphate materials on the nitinol stent was one of the best techniques to create firmly attached coating on it and reduce toxic nickel ions elution.
We aimed to examine the clinical usefulness of a new World Health Organization classification scheme for salivary gland mucoepidermoid carcinoma, and to identify the factors most strongly associated with prognosis and outcome.
The clinicopathological features of 45 patients who received treatment for mucoepidermoid carcinoma between 1986 and 2010 were retrospectively investigated.
The overall disease-specific 5-year survival rate was 81.8 per cent. The rate for patients with low-grade tumours (92.5 per cent) was significantly higher than that for patients with intermediate or high-grade tumours (52.2 per cent). Univariate analysis revealed that five factors were significantly associated with five-year survival: age, tumour stage classification, lymph node status, histological grade and treatment method. Four factors were significant in multivariate analysis: age, sex, tumour stage classification and lymph node status.
The new World Health Organization classification was useful in predicting disease progression in patients with mucoepidermoid carcinoma. Patients with high-grade tumours or other prognostic factors positively associated with disease progression should be carefully evaluated and monitored.
The feasibility of using a photoconductor with a Ga2O3/CuGaSe2 heterojunction for visible light sensors was investigated. CIGS chalcopyrite semiconductors have both a high absorption coefficient and high quantum efficiency. However, their dark current is too high for image sensors. In this study, we applied gallium oxide (Ga2O3) as a hole-blocking layer for CIGS thin film to reduce the dark current. Experimental results showed that the dark current was drastically reduced, and an avalanche multiplication phenomenon was observed at an applied voltage of over 6 V. However, this structure had sensitivity only in the ultraviolet light region because its depletion region was almost completely spread in the Ga2O3 layer since the carrier density of the Ga2O3 layer was much lower than that of the CIGS layer. These results indicate that the Ga2O3/CuGaSe2 heterojunction has potential for use in visible light sensors but that we also need to increase the carrier density of the Ga2O3 layer to shift the depletion region to the CIGS film.
Nonvolatile unipolar resistive switching has been observed in Sm doped BFO thin films in Pt/Sm: BFO/SRO stack geometry. The initial forming voltage was found to be ∼ 11 V. After the forming process repeatable switching of the resistance of Sm:BFO film was obtained between low and high resistance states with nearly constant resistance ratio ∼ 105 and non overlapping switching voltages in the range of 0.7-1 V and 4-6 V respectively. The temperature dependent measurements of the resistance of the device indicated metallic and semiconducting conduction behavior in low and high resistance states respectively. The current conduction mechanism of the Pt/Sm:BFO/SRO device in low resistance states was found to be dominated by the Ohmic behavior while in case of high resistance state and at high voltages it deviated significantly from normal Ohmic behavior and was found to correspond the Pool-Frankel (PF) emission. The Pt/Sm:BFO/SRO structure also showed efficient photo-response in high and low resistance states with increase in photocurrent which was significantly higher in low resistance state when illuminated with white light.
We employ Monte Carlo simulations of the electron transport that occurs within the two-dimensional electron gas formed at a ZnO/ZnMgO heterojunction. Steady-state and transient electron transport results are presented. We find that at high fields, increases in the free electron concentration result in decreases in the electron drift velocities.
Manganese oxide based nanoparticles were synthesized by sol-gel process. Methanol, ethanol, and propanol were used as alternative solvent during sol-gel process with manganese acetate as precursor for the preparation of pristine manganese oxide. Hybrid MnOx modified by additions of carbon nanotubes was further prepared. Smallest particle size was observed for manganese oxide prepared from propanol, with diameters range from 16 nm to 50nm. XRD results showed that the as prepared manganese oxide based samples at calcination temperature of 300°C and above were composed of Mn2O3 as dominant phase, with Mn3O4 as minor phase. Specific capacitance measured from two electrode systems of manganese oxide prepared from methanol, ethanol, and propanol at scan rate of 10 mV/s were 88.3, 66.0, 104.8 F/g and the result for the hybrid sample was 140.5 F/g. The highest capacitance of the MnOx revealed a specific capacitance of 231.4 F/g when a 1:1 mixture of propanaol and methanol was employed as the solvent for the sol preparation. Results from electrochemical impedance spectroscopy (EIS) also showed superior electrochemical properties of the hybrid sample over pristine manganese oxide samples.
Strong short electric field pulses are used to generate broadband terahertz radiation. Understanding the transport properties under such conditions is very important for the understanding of numerous terahertz photonic and electronic devices. In this paper, we report on transport simulations of the electrons within bulk wurtzite zinc oxide for pulsed high electric fields, with pulse durations of up to 400 fs. We focus on how key electron transport characteristics, namely the drift velocity and the corresponding average energy, vary with time since the onset of the pulse. For sufficiently high-field strength selections, we find that both of these parameters exhibit peaks. In addition, an electron drift velocity undershoot is observed following this peak. A contrast with the case of gallium nitride is considered; undershoot is not observed for the case of this material. Reasons for these differences in behavior are suggested.
We review some recent results related to the steady-state and transient electron transport that occurs within bulk wurtzite zinc oxide. We employ three-valley Monte Carlo simulations of the electron transport within this material for the purposes of this analysis. Using these results, we devise a means of rendering transparent the electron drift velocity enhancement offered by transient electron transport over steady-state electron transport. A comparison, with results corresponding to gallium nitride, indium nitride, and aluminum nitride, is provided. The device implications of these results are then presented.
This study aimed to investigate the function of tissue plasminogen activator in the olfactory epithelium of mice following neural injury.
Transmission electron microscopy was used to study the changes in the morphology of the olfactory epithelium 1–7 days after surgical ablation of the olfactory bulb (bulbectomy).
Prior to bulbectomy, a uniformly fine material was observed within some regions of the olfactory epithelium of mice deficient in tissue plasminogen activator. At 2–3 days after bulbectomy, there were degenerative changes in the olfactory epithelium. At 5–7 days after bulbectomy, we noted drastic differences in olfactory epithelium morphology between mice deficient in tissue plasminogen activator and wild-type mice (comparisons were made using findings from a previous study). The microvilli seemed to be normal and olfactory vesicles and receptor neuron dendrites were largely intact in the olfactory epithelium of mice deficient in tissue plasminogen activator.
The tissue plasminogen activator plasmin system may inhibit the regeneration of the olfactory epithelium in the early stages following neural injury.
It is difficult to get a real scale image of the solar system through lecture. A scale model is a classical and one of good solutions (e.g. Handa et al.2003, Handa et al.2008). Through this model, people living in or visiting to the city can physically understand the scale of the solar system. This scale gives 1 cm for Earth's diameter and 115 m for 1 AU. However, some gadget is required to make it attractive for public citizens.