Remote monitoring and control systems are being used with more frequency, but the characteristics of situational awareness and decision-making from remote locations are largely unknown. Remote operators’ sources of information differ from on-board sources greatly in terms of perspective, field of view, and available data type (qualitative or quantitative). This study focused on clarifying the cognitive effects of first- and third-person perspectives on ship handling. A working hypothesis was formulated based on the findings of visual information processing and previous studies and tested using a developed ship handling simulator. The results revealed that: (1) the cognitive characteristics of the first-person perspective make it more effective in safely guiding ship handling than does the third-person perspective, and (2) the deviation in cognitive characteristics is prominent where collision can be easily avoided. The findings will aid the development of on-board and remotely piloted vessels and ensure the safety of their crews.

The effect of n-3 long-chain PUFA (n-3 LCPUFA) on depression in healthy subjects is unclear, and most of the previous studies have focused on populations eating Western diets with lower fish intake. The present study investigated the association between blood levels of n-3 LCPUFA and depressive symptoms in Japanese community dwellers with higher n-3 LCPUFA blood levels. A cross-sectional study was conducted from 2006 to 2008, including 1050 men and 1073 women aged 40 years or older from the National Institute for Longevity Sciences – the Longitudinal Study of Aging. The Center for Epidemiologic Studies Depression Scale (CES-D) was used to assess depressive symptoms. Multiple logistic regression analysis was performed to estimate the OR and 95 % CI for a CES-D score ≥16. Serum concentrations of n-3 PUFA, but not n-6 PUFA, were inversely associated with depressive symptoms. Compared with the lowest quintile, the adjusted OR for serum EPA at the fourth and fifth quintiles were 0·55 (95 % CI 0·35, 0·85) and 0·64 (95 % CI 0·42, 0·98), respectively, and at the fifth quintile for DHA it was 0·58 (95 % CI 0·37, 0·92), for the presence of depressive symptoms (Pfor trend=0·013 and 0·011, respectively). Serum levels of EPA and DHA were inversely associated with depressive symptoms in Japanese community dwellers with higher blood levels of n-3 LCPUFA, suggesting that n-3 LCPUFA intakes corresponding to higher levels in a Japanese population may have implications for a lower prevalence of depression.

Obesity is one of the major health problems throughout the world. The present study investigated the preventive effect of epilactose – a rare non-digestible disaccharide – on obesity and metabolic disorders in mice fed high-fat (HF) diets. Feeding with HF diets increased body weight gain, fat pad weight and adipocyte size in mice (P<0·01), and these increases were effectively prevented by the use of supplemental epilactose without influencing food intake (P<0·01). Caecal pools of SCFA such as acetic and propionic acids in mice fed epilactose were higher compared with mice not receiving epilactose. Supplemental epilactose increased the expression of uncoupling protein (UCP)-1, which enhances energy expenditure, to 2-fold in the gastrocnemius muscle (P=0·04) and to 1·3-fold in the brown adipose tissue (P=0·02) in mice fed HF diets. Feeding HF diets induced pro-inflammatory macrophage infiltration into white adipose tissue, as indicated by the increased expression of monocyte chemotactic protein-1, TNF-α and F4/80, and these increases were attenuated by supplemental epilactose. In differentiated myogenic-like C2C12 cells, propionic acid, but not acetic or n-butyric acids, directly enhanced UCP-1 expression by approximately 2-fold (P<0·01). Taken together, these findings indicate that the epilactose-mediated increase in UCP-1 in the skeletal muscle and brown adipose tissue can enhance whole-body energy expenditure, leading to effective prevention of obesity and metabolic disorders in mice fed HF diets. It is suggested that propionic acid – a bacterial metabolite – acts as a mediator to induce UCP-1 expression in skeletal muscles.

The overnight preservation of bovine ovaries would be highly useful in the subsequent harvest of viable oocytes for reproductive study. The present study aimed to optimize conditions for overnight preservation of bovine ovaries by examining the effects of temperature, solution and supplementation. In Experiment 1, the rate of development to the blastocyst stage of oocytes derived from ovaries preserved at 15°C was higher than that at either 5 or 25°C (p < 0.05). In Experiment 2, the rate of development to the blastocyst stage of oocytes derived from ovaries preserved in University of Wisconsin solution was higher than when PBS or saline was used (p < 0.05). In Experiment 3, oocytes preserved in saline supplemented with 0.3 mM glutathione (GSH) exhibited an increase in the rate of blastocyst formation compared with oocytes supplemented with 0 or 3 mM GSH (p < 0.05). In Experiment 4, supplementation with 10 μM epigallocatechin gallate during ovary preservation increased the rate of blastocyst formation (p < 0.05). The blastocysts derived from ovaries stored in saline supplemented with GSH at 15°C for 24 h were shown to develop into normal offsprings following transfer to recipient heifers. Our studies indicate that bovine IVM/IVF embryos derived from ovaries preserved in saline supplemented with an antioxidant at 15°C for 24 h can successfully develop to the blastocyst stage and result in offspring.

In this study, we investigated the effects of methyl-β-cyclodextrin (MBCD) on in vitro fertilization and the subsequent development of bovine oocytes. Bovine oocytes matured in serum-free medium were inseminated with frozen–thawed sperm pre-incubated in protein-free modified Brackett and Oliphant medium (BO) containing various concentrations of MBCD for various periods. MBCD decreased the frequency of live sperm, however enhanced the capacitation and acrosome reaction of the live sperm. Pre-incubation of sperm with 0.5, 1.0 and 1.5 mM MBCD for 2 and 4 h increased the frequency of normal fertilization. Embryos derived from oocytes fertilized with spermatozoa pre-incubated with MBCD developed normally to the blastocyst stage and term. There were individual differences and similar tendencies in four different sires in terms of the effects of MBCD upon fertilization. These results indicate that the pre-incubation of bovine sperm with MBCD affects viability and capacitation status of the sperm and promotes fertilization in vitro. Embryos derived from oocytes fertilized with sperm pre-incubated with MBCD developed normally to the blastocyst stage and term.

We have demonstrated enhancement-mode n-channel gallium nitride (GaN) MOSFETs on Si (111) substrates with high-temperature operation up to 300 °C. The GaN MOSFETs have good normally-off operation with the threshold voltages of +2.7 V. The MOSFET exhibits good output characteristics from room temperature to 300 °C. The leakage current at 300°C is less than 100 pA/mm at the drain-to-source voltage of 0.1 V. The on-state resistance of MOSFET at 300°C is about 1.5 times as high as that at room temperature. These results indicate that GaN MOSFET is suitable for high-temperature operation compared with AlGaN/GaN HFET.

In this report, we have demonstrated enhancement-mode n-channel GaN MOSFETs on silicon (111) substrates. We observe a high field-effect mobility of 115 cm2/Vs, the best report for GaN MOSFET fabricated on a silicon substrate to our knowledge. The threshold voltage was estimated to be +2.7 V, and the maximum operation current was over 3.5 A. This value is the largest which have ever been reports.

Selective heteroepitaxial growth of α-Al2O3 thin films on a NiO layer was investigated using an electron-beam assisted pulsed laser deposition process. The epitaxial NiO layer was grown on an ultrasmooth sapphire (α-Al2O3 single crystal) (0001) substrate. The α-Al2O3 thin film could be grown epitaxially only in the electron-beam irradiated region of the epitaxial NiO layer at 300°C, while the amorphous Al2O3 film was grown in the non-irradiated region. The homoepitaxial growth of α-Al2O3 thin films could not be attained on the sapphire (0001) substrate at 300°C. This indicates that the electron-beam irradiation enhances heteroepitaxial growth of the α-Al2O3 thin films on the NiO layer at 300°C. When we annealed the epitaxial Al2O3/NiO bilayer film at 350°C in a hydrogen atmosphere, we could reduce only the NiO layer to an epitaxial Ni metal layer, allowing the fabrication of epitaxial Al2O3/Ni (insulator/metal structure) films. The fabricated Al2O3/Ni bilayer films exhibited a very smooth surface.

Using a relativistic electromagnetic particle code, we investigate positron acceleration in a shock wave propagating obliquely to an external magnetic field ${\bf B} _0 $ in an electron–positron–ion plasma. After an encounter with a shock wave, some positrons are reflected and then accelerated along the magnetic field. They stay in the shock transition region and have velocities nearly parallel to ${\bf B} _0 $. Owing to the deformation of the wave profile, the acceleration can become stagnant. However, if the shock speed $v_{\rm sh}$ is close to $c \cos \theta $, where $c$ is the speed of light and $\theta $ is the angle between the wave normal and ${\bf B} _0 $, the acceleration can start again. In this second stage acceleration, three types of motion are found. The first type is the same as that in the first stage. In the second type, particles gain energy from the electric field perpendicular to the magnetic field in association with large-radius gyromotion. The third type of motion resembles the curtate cycloid in the wave frame. We give theoretical estimates for the energy increase in these processes.

We investigated an AlGaN/GaN heterostructure field effect transistor (HFET) on Si substrates using a multi-wafer metalorganic vapor phase epitaxy (MOVPE) system. It was confirmed that a GaN film with smooth surface and without any crack was obtained. To increase a resistance of a GaN buffer layer, the carbon (C) -doping was carried out by controlling the V/III ratio and the growth pressure. The breakdown voltage of the buffer layer was dramatically improved by introducing the C. As a result, the breakdown voltage was about 900 V when the C concentration was about ∼8×1018 cm−3. After while, an AlGaN/GaN heterojunction FET (HFET) on a C-doped GaN buffer layer was fabricated. We achieved the breakdown voltage of over 1000 V and the maximum drain current of over 150 mA/mm, respectively. It was found that the C doped buffer layer is very effective for improving the breakdown voltage of AlGaN/GaN HFETs.