Sample geometry effects on mechanical strengths of gold micro-cantilevers are evaluated by a micro-bending test. Six micro-cantilevers with the same length of 50 μm are prepared, and the width and the thickness are varied to examine individual effects on the yield stress. The yield stress increases from 428 to 519 MPa when the thickness decreases from 11.1 to 6.0 μm. No obvious dependency is observed when varying the width. The results reveal that the thickness and the width each has a different influence on the yield stresses of micro-cantilevers evaluated by the bending test, which is the sample geometry effect.

Rain-on-snow events can cause wet snow avalanches. Laboratory experiments were carried out to investigate the change in snow strength with increasing water content through rainwater percolation. Snowpack was artificially prepared consisting of a thin ice layer and fine compacted snow, and rainfall (2mmh–1) was artificially applied 22–25.5 and 49–52 hours after the snowpack was formed. Snow hardness was measured with a push–pull force gauge to indicate the snow strength before and after each rain-on-snow event. After the first rainfall, the upper half of the snowpack became wet and a rapid decrease in snow hardness was observed. After the second rainfall the rainwater penetrated the ice layer, high water content was observed above the ice layer but the hardness exceeded that estimated from an empirical relationship between hardness and water content. Micrographs of the snow particles suggest that the delay in grain coarsening observed near the wetting front induces the harder than estimated snow condition.

A 60 GHz tandem coupler using offset broadside coupled lines is proposed in a WLP (Wafer Level Packaging) technology. The fabricated coupler has a core chip area of 750 μm × 385 μm (0.288 mm2). The measured results show an insertion loss of 0.44 dB, an amplitude imbalance of 0.03 dB and a phase difference of 87.6° at 60 GHz. Also the measurement shows an insertion loss of less than 0.67 dB, an amplitude imbalance of less than 0.31 dB, a phase error of less than 3.7°, an isolation of more than 29.7 dB and a return loss of more than 27.9 dB at the input ant coupled ports and more than 14.3 dB at the direct and isolated ports over the frequency band of 57-66 GHz, covering 60 GHz band both in Japan and US. To the best of our knowledge the proposed coupler achieves the lowest ever reported insertion loss and amplitude imbalance for a 3-dB coupler on a silicon substrate. With its superior performance and lower cost compared to the CMOS counterparts, the proposed coupler is a suitable candidate for low-cost high-performance millimeter-wave systems.

The Japan Atomic Energy Agency (JAEA) established the Horonobe Underground Research Laboratory (URL) Project at Horonobe, in Hokkaido, Japan to enhance reliability of nuclear waste disposal technologies to be developed in deep sedimentary environments. JAEA has undertaken a number of in-situ experiments to determine changes in the properties of the host rock and the extent of the excavation disturbed zone (EDZ) created by the excavation of underground galleries for the disposal of radioactive waste. This paper reports a seismic tomography survey (using a hammer seismic source) of the “140m Gallery” at a depth of 140m below the surface of the Horonobe URL. The observation area was 3m square on the horizontal plane along the sidewall of the 140m Gallery. The measurement was repeated with the progress of excavation of a tunnel. In this experiment, the distribution of seismic velocity in the rock around the new tunnel and its decrease as the tunnel was dug, were observed using a simple small-scale seismic tomography system. The data collected show that this system can be used to capture the EDZ around tunnels.

Our preliminary clinical trial showed that consumption of cooked rice of a Japanese common cultivar Yukihikari improved atopic dermatitis associated with a suspected rice allergy, although the underlying mechanisms remain unclear. We hypothesised that the ameliorating effect of Yukihikari on atopic dermatitis is associated with the gut microbiota. BALB/c mice were fed a synthetic diet supplemented with uncooked and polished white rice powder prepared from one of four different cultivars: Yukihikari, rice A (common rice), rice B (brewery rice) and rice C (waxy rice). Denaturing gradient gel electrophoresis of PCR-amplified 16S rRNA gene fragments showed that the composition of faecal microbiota was different between mice fed Yukihikari and those fed rice A. Analysis of the 16S rRNA clone library and species-specific real-time PCR showed that the abundance of Akkermansia muciniphila, a mucin degrader, tended to be lower in mice fed Yukihikari. The incidence of allergic diarrhoea induced by oral administration of ovalbumin in systemically immunised mice was lower in mice fed Yukihikari, albeit with no difference in serum antibodies specific to ovalbumin. In a separate experiment, serum antibody levels specific to orally administered ovalbumin were lower in mice fed Yukihikari. Additionally, the translocation of horseradish peroxidase in isolated segments of ileum and colon tended to be lower in mice fed Yukihikari, suggesting a reduction in gut permeability in mice fed Yukihikari. These data indicate that changes in the gut microbiota of mice fed Yukihikari could be advantageous in the prevention of food allergy.

An avian retinopetal nucleus, the isthmo-optic nucleus (ION), is known to receive predominant inputs from the ipsilateral optic tectum. We injected biocytin into the ION in the Japanese quail, and retrogradely labeled tectal neurons projecting to the isthmo-optic (IO) neurons, or the tecto-IO neurons, with an extraordinary Golgi-like quality. Somata of the tecto-IO neurons were located in layer 9 of the tectum. The tecto-IO neurons did not have apical dendrites extending into superficial retino-recipient layers (layers 2–7), but had descending dendrites ramified in layers 9–12. They also possessed short ascending dendrites ramifying in the upper half of layer 9. This dendritic morphology suggests that main input to the tecto-IO neurons may not be of retinal origin. The tecto-IO neurons were spatially arranged in a regular pattern. Distances between neighboring tecto-IO neurons were 50–100 μm. The dendrites of each tecto-IO neuron were not widely dispersed in the horizontal plane, and were confined in a vertically oriented column of 100–200 μm diameter. They possessed axon collaterals extending horizontally in layers 12 and 13. The estimated total number of the tecto-IO neurons was approximately 7000–10,000, which is almost identical to the total cell number of the IO neurons. To label a small number of the tecto-IO terminals, biocytin was injected into a confined area of the optic tectum. The tecto-IO fibers densely arborized in a restricted space of the ION, which is comparable to the dimension of dendritic arborization of individual IO neurons. It is suggested that single tecto-IO neurons may make contact with single IO neurons. IO neurons are known to make synaptic contact with single target cells (association cells of Cajal) in the retina (Uchiyama & Ito, 1993; Uchiyama et al., 1995). The arborization pattern of the tecto-IO neurons' dendrites indicates that the tecto-IO neurons receive very local information in sensory and sensorimotor coordinate space. The morphology of the tecto-IO terminals suggests that the spatially confined information that drives the tecto-IO neurons is sent in parallel to single IO neurons, and then further to single retinal association cells of Cajal. Cellular-level restricted projection patterns of the tecto-isthmo-retinal system may reflect its function for centrifugal control of retinal function.

We have investigated physical and electrical properties of Al2O3, HfO2, and their alloy films deposited on 300mm Si wafers by Atomic Layer Deposition (ALD). It is found that Al2O3 films are not crystallized even after the heat treatment of 1050°C, while HfO2 films are already crystallized even after a-Si deposition (530°C). The crystallization temperature can be higher by adding Al2O3 to HfO2. It is confirmed by in-plane XRD and plane views of TEM that HfAlOx films with lower Hf content (Hf/(Hf+Al) <30%) are amorphous without phase separation after annealing at 1050°C and 5sec. The dependences of equivalent oxide thicknesses (EOT) on the physical thicknesses of Al2O3, HfAlOx (Hf/(Hf+Al)∼22%), and HfO2 films in poly-silicon gate capacitors indicate that those dielectric constants k are ∼9, 14, and 23, respectively. The gate dielectric with EOT of 1.5nm and the leakage current density Jg of 3mA/cm2 can be fabricated with 2nm-thick HfAlOx (22%) film.

The biological role of peroxisome proliferator-activated receptor γ (PPARγ) was investigated by gene targeting and case±control study of the Pro12Ala PPARγ2 polymorphism. Homozygous PPARγ-deficient embryos died at 10.5–11.5 days post conception (dpc) due to placental dysfunction. Heterozygous PPARγ-deficient mice were protected from the development of insulin resistance due to adipocyte hypertrophy under a high-fat diet, whose phenotypes were abrogated by PPARγ agonist treatment. Heterozygous PPARγ-deficient mice showed over-expression and hypersecretion of leptin despite the smaller size of adipocytes and decreased fat mass, which may explain these phenotypes at least in part. This study reveals a hitherto unpredicted role for PPARγ in high-fat diet-induced obesity due to adipocyte hypertrophy and insulin resistance, which requires both alleles of PPARγ. A Pro12Ala polymorphism has been detected in the human PPARγ2 gene. Since this amino acid substitution may cause a reduction in the transcriptional activity of PPARγ, this polymorphism may be associated with decreased insulin resistance and decreased risk of type 2 diabetes. To investigate this hypothesis, we performed a case±control study of the Pro12Ala PPARγ2 polymorphism. In an obese group, subjects with Ala12 were more insulin sensitive than those without. The frequency of Ala12 was significantly lower in the diabetic group, suggesting that this polymorphism protects against type 2 diabetes. These results revealed that in both mice and humans, PPARg is a thrifty gene mediating type 2 diabetes.

Formation of shallow donors has been studied in 100-keV hydrogen-implanted n-type silicon with a dose of 1×1015 cm−2. Annealing experiments are made in the temperature range 100 to 800°C. Gold Schottky contacts are fabricated on these samples to obtain carrier concentration profiles. The hydrogen profiles are measured by secondary ion mass spectroscopy. In the annealing temperature range 350 to 450°C, an increase of the carrier concentration is observed near the surface region with almost flat depth profiles. The well- known hydrogen-related donors (1st shallow donors) disappear around 400°C, while shallow donors (2nd shallow donors)observed here decrease above 500 °C. Hydrogen profiles show almost no change in the 2nd donor formation temperatures, although hydrogen starts to outdiffuse at 250°C. This indicates that the 2nd shallow donors are related to hydrogen atoms and to implantation-induced damage. The implantation-induced defects trap diffusing hydrogen atoms, which leads to the formation of the 2nd shallow donors.

The change of the concentration of electron traps in n-type Si induced by P+ implantation (300keV, l×109 cm−2) with subsequent H+-implantation has been studied by deep level transient spectroscopy. H+-implantation is performed at room temperature to a dose of 2×1010cm−2 in the range 30 to 120keV. First P+ implantation induces six electron traps (Ec-0.12, 0.15, 0.21, 0.26, 0.39, 0.49eV). H+-implantation additionally induces an electron trap (Ec-0.32eV) which is related to hydrogen. The subsequent H+-implantation partly decreases the concentration of the electron traps induced by P+ implantation, although it increases the concentrations near the H+ projected range. 30 keV H+-implantation is mdst effective to reduce the trap concentration. The reduction of the concentration of the traps is ascribed to the reaction of pre-existing defects with interstitial or vacancy defects formed by subsequent H+-implantation.

Effects of rapid thermal annealing (RTA) with a SiNx encapsulant on molecular beam epitaxial GaAs are studied with deep level transient spectroscopy (DLTS) measurements and x-ray photoelectron spectroscopy (XPS) measurements. The RTA was performed at various temperatures form 800°C to 1100°C for 6sec. The electron trap EL2 is produced by the RTA above 850°C The EL2 depth profile produced after the RTA is fitted with a complementary error function. The SiNx cap layer is more effective to prevent the formation of the EL2 than the SiO* cap layer during the RTA, because the critical temperature of the SiNx cap where the EL2 concentration starts to increase is higher than that of the SiOx cap. Slight increase of the oxidized Ga atoms is observed after the RTA near the cap surface. The enhancement of the EL2 trap is discussed considering the outdiffusion of Ga atoms into the cap layer during the RTA.

An ITO/a-Si:H Schottky Photodiode(PD) with Mo as a barrier metal at Al/ITO contact has been made and it shows its useful characteristics. The PD without Mo had high dark current proportional to the contact-via-hole area and quite a large resistance at the contact area. The XPS analysis of the Al/ITO interface indicated that Al and O in ITO mutually diffused around the interface, resulting in the degradation of ITO/a-Si:H Schottky barrier. Most of the diffused Al formed aluminum oxide (AI2O3) at the Al/ITO interface, and which caused high resistance of the contact area.

Inserting Mo barrier metal 500Å thick, the dark current got less dependent on the contact area and decreased by 2/3 on 254×227 μm PD with 106×106//m contact-via-hole. The contact resistance also decreased significantly to 1/105 of those of the conventional ones. From the XPS analysis of interface, it was also found that Mo barrier metal prevented Al diffusion into the ITO and formation of aluminum oxide at the interface.