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We have been requiring more precise knowledge about the aerodynamic characteristics of airfoils especially in a low-Reynolds-number range less than 106, because of the recent miniaturisation of robots such as unmanned aerial vehicles known as UAVs or micro air vehicles known as MAVs, in addition to the importance of insect/bird flight dynamics, small-scale machines like micro fluid machineries and micro combustion engines and so on.In the present studys we investigate the relationship between various aerodynamic characteristics and attack angle α for FP (a flat plate), NACA0015 and iNACA0015 (the NACA0015 placed back to front) by numerical analysis and water-tank experiment at Re= 1.0×10^2-8.0×10^2. Then, we reveal the effects ofαupon various aerodynamic characteristics such as the lift coefficient C_L,drag coefficient C_D and the lift-to-drag ratio CL/CD. In order to discuss the revealed α effects, we further visualise the flow around the airfoils using the Q value, helicity and streamlines at α= 0 –24 deg., together with PIV analysis based on water-tank experiment. Such results suggest that FP is similar not with NACA0015 but with iNACA0015 from an aerodynamic point of view.

Starting ore (ilmenite, TiFeO3) was wet-chemically treated to remove Fe and the hydroxide of titanium was neutralized. The obtained precipitate was calcined to form CaTiO3, which was electrochemically reduced to Ti in the molten CaCl2-CaO. The wasted salt containing CaO could be recycled to form CaTiO3. The operating conditions such as (NH4)2S and tartaric acid concentrations for Fe removal, supplied charge, gas pressure and cooling atmosphere for molten salt reduction were optimized to obtain low-oxygen titanium.

Figure S1. Aβ deposition in cat brains. (a) Immunohistochemistry of the cerebrum of a 17-year-old cat (case No. 20) for Aβ42 with FA pretreatment. Aβ42 aggregates are observed in the cerebral cortex but not in the hippocampus by immunohistochemistry with FA pretreatment. Higher magnification of the parietal lobe (right). Bar = 100 μm. (b) Negative control (without primary antibody) of Fig. 1c. No staining is detected in the cytoplasm. (c) ELISA for high molecular weight Aβ oligomers. Higher amounts of Aβ oligomers were seen in the brains of aged cats (15-year-old, case No. 15; 17-year-old, case No. 20) compared to the brains of young cats (3-year-old, case No. 5; 3-year-old, case No. 6). The ratio of MAP level per unit of Aβ concentration varies depending on the sizes of the Aβ oligomers. One pM of the MAP can be estimated to yield the same signal as 1.56 pM (for 20-mer) to 5.0 pM (for 100-mer) of Aβ42 oligomers [33]. Ctx, cortex; Hpc, hippocampus. Figure S2 Western blotting analysis of the SDS fraction of the cortex (Ctx) and hippocampus (Hpc) of young cats and aged cats. (a) The band corresponding to Aβ dodecamer is detected by anti-Aβ antibody 82E1. (b) Aβ oligomers that are demonstrated in Fig. 1f are not detected by anti-ApoE antibody A299. Figure S3 Expression of tau isoforms in the developing cat brain. (a) Immunohistochemistry of the hippocampus CA1 region of a fetus (case No. 1), a 2-week-old cat (case No. 3), and a 4-year-old cat (case No. 7) for 3-repeat tau (RD3), 4-repeat tau (RD4), and hyperphosphorylated tau (AT8). Only the 3-repeat tau isoform is expressed in the fetal hippocampus. The hippocampal pyramidal cells begin to express 4-repeat tau in the 2-week-old cat (arrows). Both 3-repeat and 4-repeat tau isoforms are expressed in the hippocampus of adult cat brain. Bar = 50 μm. (b) Immunohistochemistry of the cerebral cortex of a fetal cat for hyperphosphorylated tau (AT8 and AT100). The surface layer of the fetal cerebral cortex is positive for AT8 and negative for AT100. Bar = 100 μm. Table S1 Aβ protein amino acid sequences of different animal species. Table S2 Tau protein amino acid sequences of different animal species. (PDF 10834 kb)

Two experiments examined interval timing behavior in mice and rats. In the first experiment, subjectswere mice, and in the second one they were rats. The animals were trained using the peak procedure that was avariant of a discrete trial fixed interval (DT-FI) schedule. On food trails, the first lever press response more than30-s after tone stimulus onset terminated the stimulus and presented a food pellet. On empty trials, the tonestimulus lasted for 90-s with no food. The temporal distributions of responses in mice and rats were calculatedby averaging responses over 180 empty trials. Training progressed in both animals in a way similar to Gaussianfunction curve. Peak time, which shows the peak of regression curve fitting the Gaussian function, correspondedto 30-s with wide variability in both experiments. This proved to be a good index to the interval timing behavior.In the second experiment, we considered various regression fitting variables, especially concerning the numberof trials. Temporal distribution seems to be affected by various factors including individual differences intraining sessions.

The purpose of this experiment was to examine event-related potentials (ERPs) recoreded from the rat's hippocampus and cerebellum during a passive auditory oddball task. It has beeen predicted that mismatch negativity like (MMN-like) and P3-like components are elicited by the infrequent stimuli in the hippocampus. Further it was questioned that whether MMN-like and P3-like components can be observed at the cerebellum. ERPs recorded from those regions consisted of P1,N1,P2,N2,and P3-like components. P3-like component was obscurely elicited by infrequent stimuli at the hippocampus and the cerebellum. In both regions, a significant difference in N2 amplitude between infrequent and frequent stimuli was observed. N2 component of the rat may correspond with MMN of the human. No significant differences of these components amplitude between infrequent and frequent stimuli were found for other components. N1 latency at the cerebellum was significantly shorter than those in the hippocampus. Correlation analysis revealed that the maximal correlation coefficient between the cerebellum and the hippocampus was obtained at -20.0ms (max : -56,min : -7). This finding suggests that information processing in the cerebellum may be carried out earlier than that in the hippocampus.

Background: There are insufficient data at present on cancer risk after exposure of heavy ions, to the fetal and childhood periods. Using animal models, we studied the age-at-exposure effects of heavy ions on cancer induction and lifespan shortening for radiation protection for fetuses and children. \nMaterials and Methods: Fifty female and male B6C3F1 mice per group were exposed to gamma rays (137Cs) or carbon ions (13 keV/µm) at various ages from fetal to mature adulthood periods. Mouse ages at the time of irradiation included pre-implantation (3 days post-conception (dpc)), major organogenesis (13 dpc), late fetal (17 dpc), neonatal (1 week after birth), infantile (3 weeks), young adulthood (7 weeks) and mature adulthood stages (15 weeks). The doses ranged between 0.2 and 4 Gy for gamma rays and 0.2 and 2 Gy for carbon ions. The mice were observed until moribund and their lifespan and the developed cancers were analyzed. \nResults and Discussion: Our study indicated that female mice appeared to be more susceptible to radiation-induced lifespan shortening than male mice. Effect of gamma-rays on lifespan shortening was more manifested when irradiated at neonatal than adult stage. Surprisingly, irradiation with gamma rays at the late fetal stage had little influence on lifespan shortening compared to infant and adulthood exposures. On the other hand, carbon ions were more potent in reducing lifespan than gamma rays when female neonatal mice were exposed. When carbon ions were exposed, however, fetuses were as susceptible as infants. The results on the lifespan shortening suggest a larger RBE of carbon ions for fetuses than later stages. The RBE of carbon ions for reducing the tumor-free survival rate was ~1.0 for fetuses, suggesting that RBE of 13keV/µm carbon for cancer induction is 1.0 ~ 1.5 irrespective of age-at-exposure., 14th International Congress of Radiation Research

One of the important concerns for astronauts in space environment is cancer risk associated with cosmic radiation, including heavy particle carbon ions. But little information on cancer risk is available. Biological effects of heavy ions have been extensively investigated using HIMAC and GSI synchrotrons, and generally high RBEs for cell killing and mutation induction have been shown. Murine T-cell lymphomas (TL) can be reproducibly induced by carcinogenic agents such as radiation and chemicals, and this murine model is considered to be useful in the search for characterization of genes involved in the development of human lymphocytic leukemia. In our previous studies, B6C3F1 female mice were exposed to 1.6 Gy whole-body carbon-ion radiation (290 MeV/u; dose average LET, 60 keV/um, spread-out Bragg peak, 6 cm) for 4 consecutive weeks or to 1.6 Gy X-ray radiation. Carbon-induced and X-ray-induced lymphomas showed similar phenotypes, except size of lymphomas. Molecular analysis revealed that the high frequency of loss of heterozygosity (LOH) on chromosomes 4, 11, 12 and 19 in both lymphomas.There was a clear difference of LOH status between two lymphomas; its frequency was much higher for chromosome 11 but lower for chromosome 12 in carbon-ion-induced lymphomas compared to X-ray-induced ones, suggesting mechanistic difference between carbon-ion- and X-ray-induced lymphomagenesis. In the present study, we aimed to clarify the carbon-ion-specific genomic changes. The region of frequent LOH on chromosome 11 was determined using 11 microsatellite markers, and the difference was not found. The alterations of Ikaros on chromosome 11, including altered splicing, point mutations, null expression and insertion, were analyzed. The alteration of Ikaros was similar between the carbon-ion- and X-ray-induced lymphomas., 第23回日本宇宙生物科学会