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Due to the complete compensation, defect complex (2VCu+InCu), namely two Cu vacancies and In located at Cu site, is stable in CuInSe2 (CIS). It is known that the series of ordered defect compounds (ODC) are constracted by ordering the defect complex. Based on the total energy calcalation by using the Korringa-Kohn-Rostoker coherent potential approxiamtion (KKR-CPA) method, we discuss phase separation of the CIS with the defect complexes into ODC and CIS. Since the band alignment between ODC and CIS is calculated to be type 2, effective electron-hole separation at the interface between ODC and CIS can be expected. This causes the enhancement of conversion efficiency of CIS-based solar cell materials.

Based on experimental results, using the Korringa-Kohn-Rostoker coherent potential approximation (KKR-CPA) method and Monte Carlo simulation, we study the mechanism of ferromagnetic behavior of (In,Fe)As. We show that with doped Be atoms occupying in interstitial sites, chemical pair interactions between atoms and magnetic exchange interactions between Fe atoms change due to electron concentration. Therefore, by controlling the doping process, magnetic behavior of (In,Fe)As is controlled and ferromagnetism is observed in this semiconductor.

The ferromagnetism in ZnO-based diluted magnetic semiconductors (DMSs) is investigated based on the first principles calculations. The electronic structure of a ZnO-based DMS is calculated using the Korringa–Kohn–Rostoker method combined with the coherent potential approximation based on the local density approximation. The stability of the ferromagnetic state compared with that of the spin-glass state is systematically investigated by calculating the total energy difference between them. It is found that the ferromagnetic state is more stable than the spin-glass state in V-, Cr-, Fe-, Co- or Ni-doped ZnO without any additional carrier doping treatments. In the case of the Mn-doped ZnO, the spin-glass state is stable at a carrier concentration of 0%, but the ferromagnetic state is stabilized by the hole doping treatment. Analyzing the calculated density of states, it is proposed that the origin of the stabilization of the ferromagnetism is a double-exchange mechanism.

Background. Polymorphism of the collagen type Iα1 gene (COLIA1) has been shown to be involved in bone density in the general population. However, the significance of this polymorphism has not been examined in patients with chronic renal failure. Methods. We first determined the COLIA1 Bal I restriction fragment length polymorphism (RFLP) at the Sp 1 binding site, and, next, we measured biochemical bone markers and the bone mineral density (BMD) of the lumbar spine (L2–L4) and radius (distal one-third) in 181 hemodialyzed patients. Results. Distributions of the Bal I RFLP were: SS, 62%; Ss, 32%; and ss, 6%. The Z scores for the BMD and for the serum levels of Ca, P, alkaline phosphatase, intact-parathyroid hormone (PTH), osteocalcin, and tartrate-resistant acid phosphatase were not significantly different among the three genotype groups. The slope of the regression line in the age-BMD relationship, a measure of the rate of BMD decrease, was similar among the three genotypes in men, but was significantly (P < 0.05) larger in the ss group than in the SS and Ss groups in women. Conclusions. The COLIA1 polymorphism may be associated with the bone loss seen in female patients on hemodialysis.

Sensorimotor association is an essential aspect of behavior. The dorsal part of the premotor cortex (PMd) is known to have an important role in sensorimotor association. Although it is suggested that the partially segregated groups of neurons are involved in sensorimotor association in different sensory modalities, it is not yet clear whether these groups occupy the PMd to the same or different extent. Therefore, we performed a functional magnetic resonance imaging study to compare activated regions in the PMd during simple reaction-time tasks with visual and auditory cues. Eight normal volunteers performed two simple reaction time tasks with a conventional on–off design; one is with a visual cue and the other is with an auditory cue. In both tasks, two regions in the left primary motor area (M1) (4a and 4p) and the bilateral PMd were activated. The two activated regions in the left M1 occupied the same areas in both the visual and the auditory tasks. However, in the PMd, the activated regions were situate medially during the visual task and laterally during the auditory task, along the precentral sulci. There was no overlap of significantly activated regions between two tasks, and areas specifically activated during the visual task were observed in the middle of the precentral sulci, bilaterally. The results suggest that the distribution of PMd subregions involved in sensorimotor association differ when the sensory cues are in different modalities.

Angiotensin (A) II plays a critical role in vascular remodeling, and its action is mediated by type 1 AII receptor (AT1R). Recently, 15-deoxy-(Delta)(12,14)-prostaglandin J(2) and thiazolidinediones have been shown to be ligands for peroxisome proliferator-activated receptor (PPAR)-gamma and activate PPAR-gamma. In the present work, we have studied the effect of PPAR-gamma on AT1R expression in rat vascular smooth muscle cells (VSMCs). We observed that: 1) endogenous AT1R expression was significantly decreased by PPAR-gamma ligands both at messenger RNA and protein levels, whereas AT1R messenger RNA stability was not affected; 2) AII-induced increase of (3)H-thymidine incorporation into VSMCs was inhibited by PPAR-gamma ligands; 3) rat AT1R gene promoter activity was significantly suppressed by PPAR-gamma ligands, and PPAR-gamma overexpression further suppressed the promoter activity; 4) transcriptional analyses using AT1R gene promoter mutants revealed that a GC-box-related sequence within the -58/-34 region of the AT1R gene promoter was responsible for the suppression; 5) Sp1 overexpression stimulated AT1R gene transcription via the GC-box-related sequence, which was inhibited by additional PPAR-gamma overexpression; 6) electrophoretic mobility shift assay suggested that Sp1 could bind to the GC-box-related sequence whereas PPAR-gamma could not; 7) antibody supershift experiments using VSMC nuclear extracts revealed that protein-DNA complexes formed on the GC-box-related sequence, which were decreased by PPAR-gamma coincubation, were mostly composed of Sp1; and 8) glutathione S-transferase pull-down assay revealed a direct interaction between PPAR-gamma and Sp1. Taken together, it is suggested that activated PPAR-gamma suppresses AT1R gene at a transcriptional level by inhibiting Sp1 via a protein-protein interaction. PPAR-gamma ligands, thus, may inhibit AII-induced cell growth and hypertrophy in VSMCs by AT1R expression suppression and possibly be beneficial for treatment of diabetic patients with hypertension and atherosclerosis.

An on-line time differential perturbed angular correlation technique has been developed with the light probe nucleus 19F. The first on-line TDPAC measurement was carried out to determine the field gradient in Cd and quadrupole moment of 19F (0.197 MeV: I π = 5/2+, T1/2 = 89 ns).

Using β-NMR with 12B nuclei the temperature dependence of the lattice locations of boron implanted in Si is studied. At low temperature almost 100% of the implanted B is in either substitutional site or nonsubstitutional site. Above 260 K, the nonsubstitutional B rapidly becomes undetectable and disappears at a temperature higher than 325 K due to the fast spin-lattice relaxation. Above 450 K, the fraction of substitutional B increases to 100%. These experimental results are consistently explained by the thermal atomic jump and the dissociation of the defect associated with the nonsubstitutional B.

エストロゲン受容体 (ER) のPvuII, XbaI制限酵素断片長多型が透析患者の骨病変に影響を及ぼしているかを検討した. 患者末梢血から抽出したゲノムDNAを鋳型としてpolymerase chain reaction (PCR) を行い, ERのイントロン1とエクソン1を含む領域を増幅した. 得られたPCR産物を制限酵素PvuII, XbaIと反応して遺伝子多型を決定した. また骨生化学的指標として血清Ca, P, Al-P, tartrate-resistant Ac-P, intact-PTH, osteocalcinを測定するとともにdual energy X-ray absorptiometry (DEXA) 法にて腰椎正面 (L2-L4) および橈骨 (遠位端1/3) 骨塩量測定を行った. PvuII遺伝子多型の分布は, 男性 (n=126) がPP 23.0%, Pp 51.6%, pp 25.4%であり, 女性 (n=81) がPP 19.8%, Pp 38.3%, pp 42.0%であった. XbaI遺伝子多型の分布は, 男性 (n=120) がXX 5.8%, Xx 37.5%, xx 56.7%であり, 女性 (n=78) がXX 9.0%, Xx 38.5%, xx 52.6%であった. 遺伝子多型別に比較した骨生化学的指標は, 男女のどの3群間においても有意差は認められなかった. 腰椎および橈骨骨塩量のZ scoreもすべて3群間で有意差はなかった. 腰椎骨塩量のZ scoreと年齢との相関では, 女性のPvuII遺伝子多型でPP群の回帰直線勾配がPp群, pp群より有意に高値であり (p

The electronic structure of II–VI and III–V compound-based diluted magnetic semiconductors is calculated based on the local density approximation (LDA) using the Korringa–Kohn–Rostoker method combined with the coherent potential approximation. The magnetism of 3d transition-metal-atom-doped ZnO, ZnS, ZnSe, ZnTe, GaN, GaAs is investigated from first-principles. It is suggested that the double exchange mechanism stabilizes the ferromagnetism in these DMSs. In order to obtain microscopic information on the electronic structure of transition-metal-impurities in semiconductors, the hyperfine field of respective impurities in each host material is calculated. It is found that the agreement with the experimental values is not good, probably because the LDA is not sufficient to describe the core states of transition metals. However, it is suggested that the hyperfine fields clearly reflect the local magnetic moments for 3d impurities.

A genome project for the species Caenorhabditis elegans has demonstrated the presence of eight cDNAs belonging to the major intrinsic protein (MIP) family. We previously characterized one of these cDNAs known as C01G6.1. C01G6.1 was confirmed to be a water channel and newly designated as AQP-CE1 [Am. J. Physiol. 275 (1998) C1459-C1464]. In this paper, we examined the function of another MIP protein encoded by F40F9.9. This cDNA encodes a 274-amino acid protein showing a high sequence identity with mammalian aquaporin-8 (AQP8) water channel (35%) and d-TIP (34%), an AQP of Arabidopsis. The expression of F40F9.9 in Xenopus oocytes increased the osmotic water permeability (P(f)) 10.4-fold, and the activation energy for P(f) from Arrhenius plot was 4.7 kcal/mol, suggesting that F40F9.9 is a water channel (AQP-CE2). AQP-CE2 was not permeable to glycerol or urea. Oocyte P(f) was reversibly inhibited by 58% after an incubation with 0.3 mM HgCl(2). To identify the mercury-sensitive site, four individual cysteine residues in AQP-CE2 (at positions 47, 132, 149, 259) were altered to serine by site-directed mutagenesis. Of these mutants, only C132S had a P(f) similar to that of the wild-type together with an acquired mercury resistance, suggesting that Cys-132 is the mercury-sensitive site. Similar results were obtained by the mutation of Cys-132 to alanine (C132A). Replacement of Cys-132 with tryptophan decreased P(f) by 64%, but P(f) was still 2.5 times higher than that of the control. Cys-132 is located in the transmembrane helix 3, close to the transition to the extracellular loop C. These results suggest that the transmembrane helix 3, including Cys-132, might participate in the aqueous pore formation, or, alternatively, that Cys-132 might contribute to the construction of the AQP protein.

The effects of different vibration modes of resonance oscillation (RO) on the reaction selectivity of ethanol decomposition over an Ag catalyst were studied. A z -cut and an x -cut LiNbO 3 ferroelectric single crystal were used as a substrate, onto which a 100 nm Ag thin film catalyst was deposited. A z -cut and an x -cut LiNbO 3 ferroelectric single crystal were shown to provide a thickness extensional (TE) and a thickness shear (TS) mode vibration, respectively. The TE mode RO increased ethylene production without significant enhancement of acetaldehyde production, whereas the TS mode RO caused little increases for both ethylene and acetaldehyde production. In laser Doppler measurements of lattice displacement vertical to the surface, irregular standing wave patterns were induced by RO, and the lattice displacement was significantly large for the TE mode and very small for the TS mode RO.

A tracer study was performed to assign a radical produced with UV irradiation on photocatalytically active BaTi 4 O 9 for water decomposition. BaTi 4 O 9 was reduced in H 2 and oxidized in 16 O 2 , 17 O 2 or 18 O 2 at different temperatures. The behavior of oxygen exchange was investigated by thermal gravimetric analysis and Raman spectroscopy. Electron magnetic resonance spectra showed that new signals with g ⊥ =2.038 and g ⊥ =2.026 due to hyperfine splitting of 17 O − with A ⊥ =19.1 G appeared when oxidized in 17 O 2 , in addition to normal signals with g ⊥ =2.018 and g ‖ =2.004. The radical is assigned to O − produced from surface lattice oxygen of BaTi 4 O 9 .

Effects of RuO2 dispersion on the photocatalytic activity for water decomposition of BaTi4O9 (BTO) with a pentagonal prism tunnel structure and K2Ti4O9 (KTO) with a zigzag layer structure were studied. These titanates were impregnated with either a RuCl3 aqueous solution or a Ru3(CO)12 complex in THF and were subjected to oxidation at high temperatures. In comparison with the chloride, the employment of Ru3(CO)12 complex gave rise to the higher photocatalytic activity of BTO and a significant improvement of photocatalytic performance of KTO. High resolution transmission electron microscopic observation showed that the carbonyl complex led to the formation of uniformly distributed small RuO2 particles (average particle size, ρav, was 1.8 nm for BTO and 5.1 nm for KTO) than did the chloride (ρav was 2.7 for BTO and 15 nm for KTO). The tunnel structure of BTO is shown to have the high capability to disperse RuO2 as small particles, compared to the zigzag layer. The photoexcited charge formation of KTO with UV irradiation was examined by electron paramagentic resonance (EPR) measurements. A correlation between the photocatalytic activity and the ability of surface lattice O− formation is established for these titanates with different structures. The size effects of RuO2 particles on photocatalysis are discussed.

A new electrocatalyst which enables direct methane use in solid oxide fuel cells (SOFCs) was examined. The dispersion of Co 0.5 Ni 0.5 O particles into a porous-platinum-based anode increased the cell performance in an SOFC using a stabilized-zirconia electrolyte. Among the catalysts studied, Co 0.5 Ni 0.5 O, CoO, and NiO, the increase was the most prominent for Co 0.5 Ni 0.5 O. The anodic polarization resistance and the production rates of CO, CO 2 , and H 2 in the outlet gas showed a high Co 0.5 Ni 0.5 O catalytic activity for the electrochemical oxidation of methane, indicating the activation of the steam-reforming reaction caused by the formation of surface active sites in relation to the cation vacancy in the CoO-NiO solid solution.

Electronic structure of TiO 2 (rutile) based dilute magnetic semiconductors (DMS) are investigated within self-interaction-corrected local density approximation (SIC-LDA) from first-principles calculation. These results are compared with those calculated within standard LDA. It is found that the calculated band-gap energy in the host TiO 2 is different within the LDA and the SIC-LDA. We find that high-spin state is predicted within the SIC-LDA with oxygen vacancy. The calculated density of states within SIC-LDA is in good agreement with photoemission results.

We consider the following one-dimensional discrete-time cancellative model whose evolution is given by n +1 (x ) = n (x +1)+ n (x -1) (mod 2) with probability p and n +1 = 0 with probability 1-p . Concerning critical probabilities pc and pc * on a survival probability, it is known that 0.706 pc pc *

Objective: To investigate a role of the opiate system during acute hypoxic hypoxia, the effects of naloxone and morphine on hypoxic survival rate were investigated in awake adult mice. Design: Prospective, randomized, animal trial. Setting: University research laboratory. Subjects: Male dd-Y mice (n = 864 in experiment I, n = 144 in experiment II, n = 30 in experiment III). Interventions: The animals were placed in an airtight plastic chamber into which a continuous flow of 8 Umin 5% oxygen-95% nitrogen was passed. Measurements and Main Results: One and 5 mg/kg naloxone had no significant effect on the survival rate of mice subjected to acute hypoxic hypoxia, whereas 10 mg/kg naloxone decreased the survival rate. On the other hand, 2 and 5 mg/kg morphine was shown to have a protective action against acute hypoxic hypoxia. The protective effects of 5 mg/kg morphine against hypoxia was even antagonized by 5 mg/kg naloxone, which did not itself show any significant effect on the survival rate. The oxygen consumption in the morphine-treated (5 mg/kg) mice was significantly (p

The eVects of surface acoustic waves (SAWs) on the adsorptive properties of thin-film metal oxides were studied by their surface conductivity changes with gas adsorption and desorption in the presence and absence of SAWs. The conductivity increases were considerably enhanced by a 10-MHz Rayleigh SAW at 1 W with the ethanol adsorption on 10 nm n-type semiconducting ZnO and by a 20-MHz shear horizontal leaky SAW (SH-LSAW ) with the O 2 adsorption on a 30-nm p-type semiconducting NiO surface. The desorption of oxygen from the NiO was also promoted by the SH-LSAW. The interactions of the SAWs with charge carriers in the metal oxide films are mainly responsible for the enhancement of the conductivity changes, and it is proposed that the promotion of not only adsorption but also desorption is associated with the periodic features of SAW-induced lattice displacement. © 1999 Elsevier Science B.V. All rights reserved.

To evaluate the tumour imaging potential of fluorine-18 fluoromisonidazole (FMISO), we studied FMISO uptake in an experimental tumour model and examined the correlation between intratumoral distributions of FMISO, 14C-2-deoxyglucose (2DG) and 14C-methionine (Met). The study was performed using control rats with the AH109A tumour and rats with the same tumour under local hypoxia. Tumour uptake of FMISO was constant between 30 min and 2 h after injection, and the tumour to muscle ratio was 2 from 2 to 4 h. A tumour study with FMISO was scheduled at 2 h. Double-tracer autoradiography of the tumour demonstrated that in the areas of high FMISO uptake, there was low uptake of Met, while areas of low FMISO uptake showed high Met uptake. FMISO showed high grain density in the rim of the tumour surrounding the necrotic area. 2DG showed a more uniform distribution over the entire section of viable cells. The mean uptake of FMISO by hypoxic, radioresistant tumours was significantly higher than that by the control tumours (P

The effect of dynamic surface lattice vibration on the selectivity of ethanol decomposition over a thin-film copper catalyst was studied by using a shear horizontal leaky surface acoustic wave (SH-LSAW) generated by radio frequency (RF) power on a positively polarized, 36° rotated, y -cut LiTaO 3 single crystal. The surface acoustic wave (SAW) caused a remarkably high enhancement of ethylene production but a small increase in acetaldehyde production, thus indicating the SAW's ability to dramatically change the selectivity. Laser Doppler measurements showed an irregular pattern of standing waves with different amplitudes up to 5 nm during SAW propagation. Contact potential difference measurements showed the generation of a negative voltage by the SAW propagation on the positively polarized ferroelectric surface. These changes are quite similar to those previously observed for a thickness–extensional mode resonance oscillation and are associated with the characteristic features of a leaky wave. Selective production of ethylene by the SAW is proposed to be related to the enhancement of the copper surface–oxygen atom interactions through dynamic lattice displacement.

The effects of resonance oscillation (RO) with a thickness-extensional mode generated in a poled ferroelectric z-cut LiNbO 3 single crystal by rf power were studied on reaction selectivity for the ethanol decomposition of thin film Au, Ag and WO 3 catalysts deposited. For a 100 nm Ag catalyst, a 3.5 MHz RO at 3 W caused an increase in ethylene production at 573 K by a factor of 16 without any change in acetaldehyde production. The selective promotion of ethylene production by RO was also observed at 573 K for a Au catalyst in which the activity for ethylene production increased by a factor of 5. For a WO 3 catalyst the RO increased both the ethylene and acetaldehyde productions, but the former was more largely promoted than the latter. The RO caused decreases in respective activation energy. The selective production of ethylene is associated with the RO-induced strong oxygen–metal (and metal oxide) surface interactions which are produced by dynamic lattice displacement.

The dipolar broadening of the NMR on short-lived β-emitter 8Li implanted in single crystal Cu has been observed as a function of crystal orientation at several temperatures. From the orientation angle dependence of the line width, it was found that the main component of the 8Li occupies substitutional site, while about 30% of 8Li occupies octahedral interstitial site at temperatures below 300 K.

Regression analysis and neural network were applied to evaluate the contribution of major factors of propeller geometry, wake distribution and attack angle variation to propeller induced pressure fluctuations and surface force on the basis of a large volume of data stored through the cavitation tunnel tests conducted at the Shipbuilding Research Centre of Japan during these two decades.The measured and designated quantities in each case of the test and propeller geometry were readjusted as explanatory variables with properly non-dimensional expression taking into account of theoretical considerations. Not only 1st blade rate components of pressure fluctuation but also 2nd and 3rd components were examined as the target including characteristics of distribution and phase variations. Both multiple linear regression analysis and method of reconstruction learning of the layered neural network were applied.Major results obtained are(1) both cavitation number and tip clearance given as test conditions have significant effect on pressure fluctuations, as expected, (2) effect of attack angle variation and wake distribution suggested by cavitation theory is also confirmed being significant, (3) effect of propeller geometry is relatively less than that of hydrodynamic factors mentioned above, and(4) regarding the characteristics of pressure fluctuation distribution, much influence of cavitation number is shown as a new finding together with marked effect of tip clearance as expected.

The degrees of nuclear spin polarization of 8,12B, 9C, 12N, 13O, 20,21F, 23Mg, 27Si and 39Ca produced in the high energy 12,13C, 16O, 22Ne, 24Mg, 28Si and 40Ca ions on Be collisions have been measured systematically, for the technical developments of the nuclear moment studies as well as the hyperfine interaction studies by means of β-NMR technique. The fragment momentum dependences were well reproduced by the simple kinematical model. Incident energy dependence and the mass dependence as well as the reaction angle dependences were qualitatively explained by the mixing of the near and far side collisions.

The Knight shifts K for short-lived β emitters 12N and 27Si implanted in Pt have been measured by means of β-NMR technique. The results were K(12N in Pt)= +(5.8 ± 2.1)× 10-4 and K(27Si in Pt)= +(1.4 ± 0.8)× 10-3. The spin–lattice relaxation time T1 was measured for 12N in Pt. The result was T1(12N in Pt, T=300 K)= 66 ± 8 ms, thus, T1T= 20 ± 2 Ks. The present Knight shifts are in good agreement with the KKR band structure calculation with local lattice relaxation determined theoretically.

The sign of the quadrupole coupling constant eqQ of 8B in ZrB2 is determined to be positive through the β-delayed α-ray anisotropy measurement combined with the spin manipulation technique by use of the β-NMR. According to the theoretical calculation of the electric field gradient in ZrB2, the sign of the quadrupole moment of 8B is deduced to be positive.

The photocatalytic properties of RuO2-dispersed M2Ti6O13 (M=Na, K, Rb, Cs) were investigated as to the photoexcitation ability of the hexatitanates and the role of the dispersed RuO2. An EPR signal with g=2.020, g=2.018 and g=2.004 produced by UV irradiation of the hexatitanates at 77 K had a short life time in vacuum but remained stable upon exposure to gaseous molecules such as H2, He, N2, O2 and Ar. These gases brought about different stability and pressure dependence of the signal intensity, by which the radical is assigned to O- resulting from the surface lattice oxygen. The efficiency of the radical formation is associated with the presence of internal fields in the distorted TiO6 octahedra forming the rectangular tunnels of M2Ti6O13 (M=Na, K, Rb). RuO2 was dispersed on the hexatitanates by impregnation with either RuCl3(aq) solution or Ru3(CO)12 in tetrahydrofuran and the subsequent oxidation in the temperature range 573–823 K. The photocatalytic activity for water decomposition was higher for RuO2/M2Ti6O13 (M=Na, K, Rb) photocatalysts prepared using Ru3(CO)12 than for RuCl3. High resolution transmission electron microscopic images showed that uniformly distributed smaller RuO2 particles were formed for the former photocatalyst, which is considered to be responsible for the higher activity. The correlation between the concentration of the O- radical and photocatalytic activity is established, thus indicating that the O- radical is proposed to work as a hole site in the photocatalytic reaction, and the ability to separate photoexcited charges reflects the photocatalytic activity order of M2Ti6O13.

Effective exchange interactions ( J ij ) between magnetic ions in CuAlO2-based dilute magnetic semiconductors (DMS) are investigated by the Korringa–Kohn–Rostoker method combined with the coherent potential approximation within the local density approximation. It is found that the J ij between magnetic ions are short-ranged and J ij 's between magnetic ions in the same Cu-plane are ferromagnetic and ones between different Cu-planes are negligible in CuAlO2-based DMS. In comparison to this, J ij 's between magnetic impurities occupied at Al-sites are slightly longer-ranged due to the stronger hybridization effect.

Based on first-principles calculations, we propose co-doping method for increasing solubility of magnetic impurities in dilute magnetic semiconductors (DMSs). The concentration dependences of the mixing energy of DMS, such as (Ga,Mn)N, (Ga,Cr)N, (Ga,Mn)As, and (Zn,Cr)Te, show large convexity and these systems have a tendency toward spinodal decomposition. By introducing compensating impurities into these DMS, the mixing energy shows gradual transition from convex to concave concentration dependence resulting in negative mixing energy of magnetic impurities. This observation suggests that the co-doping method dramatically increases the solubility of magnetic impurities in DMS, thus high concentration doping of magnetic impurities into DMS becomes possible.

In addition to the conventional Peltier effect, we propose a new class of thermoelectric-cooling mechanism based on the adiabatic spin-entropy expansion in a quasi-one-dimensional nano-superstructure by injecting the spin current from the ferromagnetic metal to paramagnetic one. The spin-entropy expansion mechanism dominates and enhances the thermoelectric-cooling power dramatically in current perpendicular to plane-giant magneto-resistance (CPP-GMR) Co/Au nano-interface. Based upon the spin-entropy expansion mechanism, we design the new thermoelectric-cooling nano-superstructures using the newly designed half-Heusler ferromagnets NiMnSi (TC=1050 K) and self-organized quasi-one-dimensional Konbu-phase (Zn,Cr)Te with very high blocking temperature (>1000 K) by spinodal nano-decomposition.

We present computer simulations on the super-paramagnetic blocking phenomena in wide band-gap dilute magnetic semiconductors (DMSs) in particular (Ga, Mn)N. It is shown that due to the formation of magnetic nano-clusters of magnetic impurities under the spinodal decomposition, super-paramagnetic blocking temperature (TB) of the DMS is enhanced and hysteretic magnetic response can be observed at finite temperature even if Curie temperature of the whole system is nearly zero. TB higher than room temperature can be expected and the blocking phenomena explains reported ferromagnetic behaviour of wide band-gap DMS at high temperature.

Researches on Population Ecology is the former name of Population Ecology and the first volume was published in December 1952. All the papers in the first three volumes were written in Japanese with English summary; then the journal made a fresh start from Volume 4 in 1962 with all the papers written in English. Therefore Population Ecology has a long history as an international journal of ecology and we can read the whole contents on the web site of Springer. Our journal changed its name from Researches on Population Ecology to Population Ecology in 2000. I heard that the first motivation for it was the unnatural usage of English word, but there were many complications to obtain the approval for it from within the society because the renaming the journal was an influential affair on the journal itself. At that time both the merits and the demerits were also discussed. Although the simple name Population Ecology can strongly appeal to the readership, ‘population ecology’ is also the name of an established area in ecology and then it may lead to a misunderstanding that the journal only covers the studies on population dynamics for abundance or distribution. As Shimada (2000) wrote in his editorial, Population Ecology experienced the renaissance at that time and then the aims and scope of the journal were also revised and clarified as ‘‘Population Ecology publishes original research articles and reviews (including invited reviews) on various aspects of ‘population ecology’, from the individual to the community level, without page limit. Among the specific fields included are population dynamics and distribution, evolutionary ecology, ecological genetics, theoretical models, conservation biology, agroecosystem studies, and bioresource management’’ (cited from the web site of Population Ecology). Comparing it to the published articles in the present Population Ecology, a broader range of the fields are definitely covered but several areas mentioned in the aims and scope are still less represented. I believe that ‘population ecology’ has been one of the most attractive study areas in ecology, which can be proved by looking at the contents in Population Ecology. Namely ‘population ecology’ in a broad spectrum of the research fields is still a developing study area, which is affected by and also affects on other areas of ecological studies. Then we are waiting for your submission fitted to the aims and scope of Population Ecology, in which a broad sense of ‘population ecology’ is included. Your submission may contribute to lead us to a new direction of ‘population ecology’.

A New 2-year term of editorial board has just started. Some Associate Editors and some editorial board members are replaced, and I myself remain as Editor-in-Chief. We would like to continue to publish a journal with highquality articles submitted by the readers. All article types of the submissions from you are welcome. Now I believe that the quality of each scientific article is guaranteed by the several features: originality, accuracy, interest, significance, comprehensibility, and reproducibility. The peer-review process by the specialists for every submitted article should well function to authorize its quality. Unfortunately, however, the author’s intentional or accidental ‘‘insincerity’’ sometimes goes through the severe eyes of reviewers. There may be various reasons for it, but we can partly blame it for the interdiscipline of the research because the specialist cannot often cover the wide range of topics or technics in it. I believe that the interdisciplinary studies strongly contribute to make progress of that field, and then Population Ecology should seriously tackle this problem. I consider that a journal editor has some responsibility in judging the validity of the content of the articles. Thus we use CrossCheck powered by iThenticate to prevent the plagiarism in the submitted articles. This service provides us the information how much the sentences of the manuscript matches the database including a large amount of published research articles, conference proceedings and e-books, and highlights which part of the manuscript matches those database. We find it much useful to detect the plagiarism, and indeed we have decided to reject a manuscript recognized as containing plagiarism, but sometimes asked the authors to paraphrase the sentences for innocent cases. So we would like to call on you to see ‘‘Ethical Responsibilities of Authors’’ on the web site before submitting your article (http://www.springer.com/ life?sciences/ecology/journal/10144).

Thickness-extensional mode resonance oscillation (TERO), generated by radio frequency power on a thin Ag film catalyst deposited on a ferroelectric z -cut LiNbO 3 single crystal, caused a marked enhancement of ethylene production without significant changes in acetaldehyde production in ethanol decomposition: selectivity for ethylene production increased from 58% without TERO to 96% at 5 W. The activation energy of ethylene production decreased remarkably with TERO-on. Laser Doppler measurements showed that the TERO produced an irregular pattern of lattice displacement up to 60 nm which is proposed to induce strong Ag metal–oxygen atom interactions, thus promoting oxygen abstraction from the adsorbed ethanol.

A 100 nm thick Pd catalyst film was deposited on either positively or negatively polarized surfaces of a poled ferroelectric z-cut LiNbO 3 single crystal which generates a thickness-extensional mode resonance oscillation (RO) by r.f. electric power. The effects of the RO on the kinetic behavior of ethanol oxidation over a Pd catalyst were studied. A 3.4 MHz RO caused a dramatic decrease in activation energy from 156 kJ mol −1 to 36 kJ mol −1 for Pd on a positively polarized surface [(+)Pd] and to 0 kJ mol −1 for Pd on a negatively polarized surface [(−)Pd]. Reaction orders in ethanol and oxygen pressures showed that the RO changed ethanol to be weakly adsorbed on both (+)Pd and (−)Pd and oxygen to be very strongly adsorbed on (+)Pd. The RO caused opposite changes in the surface potential of the catalyst with respect to the polarized surfaces: a negative surface potential was generated for (+)Pd, and vice versa. These surface potential changes associated with an acoustoelectric effect and an electric field due to the ferroelectric substrate are responsible for the different kinetic behavior.

The purpose of this study was to identify the brain regions activated in relation to oculomotor sequence learning. Nine healthy subjects participated in the study, which consisted of three positron emission tomography scans. In the initial learning task, subjects were instructed to track a sequence of seven successive positions of visual targets and to memorize the order of the targets as well as their spatial locations. In the saccade task, subjects were instructed to track visual targets presented at random locations. In the control task, subjects were instructed to gaze at a fixation point. Fields showing significant regional cerebral blood flow change were determined from task-minus-control subtraction images. We determined that fields in the pre-supplementary motor area (pre-SMA), the intraparietal cortex, and the prefrontal cortex were activated not only in the learning-minus-control images but also in the learning-minus-saccade images. Although prefrontal and parietal activations were bilateral, pre-SMA activation was confined to the left hemisphere. The results indicate that these fields function as a part of the neural network involved in the learning of sequential saccadic eye movements.

NMR experiments are reported for VRuP which has an orthorhombic TiNiSi structure and shows anomalies in the temperature dependence of the electric conductivity and static susceptibility. A field-swept spectrum of 51V perturbed by a quadrupole interaction has been observed, which shows no anomalous temperature dependence. However, the metallic spin-lattice relaxation rate decreases in a stepwise fashion with decreasing temperature at around 200 K, in accordance with the resistivity and the susceptibility data, suggesting a possible CDW formation in this material.

We present ab initio calculations of EFGs at impurities in a TiO2 crystal. They are directly calculated from the self consistent charge distribution which is determined by the KKR method within the muffin-tin approximation and based on the local density approximation. Impurities in the crystal are simulated by the super-cell method. Considering the charge state of Sc, Ti, Nb, Cd, Ta impurities in the TiO2 , the experimental values were well reproduced. The electronic structure of these impurities is discussed by analyzing the calculated density of states.

The purpose of this study was to compute and compare the group mean HMPAO brain SPECT images of patients with senile dementia of Alzheimer’s type (SDAT) and age matched control subjects after transformation of the individual images to a standard size and shape.Methods: Ten patients with Alzheimer’s disease (age 71.6 ± 5.0 yr) and ten age matched normal subjects (age 71.0 ± 6.1 yr) participated in this study. Tc-99m HMPAO brain SPECT and X-ray CT scans were acquired for each subject. SPECT images were normalized to an average activity of 100 counts/pixel. Individual brain images were transformed to a standard size and shape with the help of Automated Image Registration (AIR). Realigned brain SPECT images of both groups were used to generate mean and standard deviation images by arithmetic operations on voxel based numerical values. Mean images of both groups were compared by applying the unpaired t-test on a voxel by voxel basis to generate three dimensional T-maps. X-ray CT images of individual subjects were evaluated by means of a computer program for brain atrophy.Results: A significant decrease in relative radioisotope (RI) uptake was present in the bilateral superior and inferior parietal lobules (p < 0.05), bilateral inferior temporal gyri, and the bilateral superior and middle frontal gyri (p < 0.001). The mean brain atrophy indices for patients and normal subjects were 0.853 ± 0.042 and 0.933 ± 0.017 respectively, the difference being statistically significant (p < 0.001).Conclusion: The use of a brain image standardization procedure increases the accuracy of voxel based group comparisons. Thus, intersubject averaging enhances the capacity for detection of abnormalities in functional brain images by minimizing the influence of individual variation.

Ligand binding to neurotransmitter and hormone receptors which couple to the Gq subclass of GTP-binding protein leads to the activation of phospholipase Cbeta (PLCbeta) which hydrolyses phosphatidyl-inositol 4,5-bisphosphate, yielding a pair of second messengers, diacylglycerol and inositol 1,4,5-trisphosphate (IP3). The expression of PLCbeta1-4 mRNAs was comparatively examined by in situ hybridization in the mouse brain. In adults, PLCbeta1 mRNA was expressed predominantly in the telencephalon, including the cerebral cortex, hippocampus, amygdala, lateral septum and olfactory bulb, with little expression in most thalamic nuclei. PLCbeta2 mRNA was distributed in the white matter, suggesting its expression in non-neuronal cells, most likely oligodendrocytes. PLCbeta3 mRNA was specifically expressed in cerebellar Purkinje cells. The highest levels of PLCbeta4 mRNA were detected in Purkinje cells. High levels of PLCbeta4 mRNA were also found in the thalamus and medial septum, whereas weak signals were detected in most telencephalic regions, thus showing an expression pattern almost reciprocal to that of PLCbeta1 mRNA. During development, such characteristic regional expression of PLCbeta1 and PLCbeta4 were observed starting in late foetal stages, while specific expression of PLCbeta2 and PLCbeta3 appeared in early postnatal stages. We conclude that despite the existence of four PLCbeta isoforms, only one or two of them is expressed in individual neurons and glial cells. The distinct expression of PLCbetas provides a molecular basis for analysing the nature of the specific signal transduction pathway leading to the production of diacylglycerol and IP3 in distinct cell types and in different regions of the brain.

A 100 nm Ag film catalyst was deposited on either a positively or negatively polarized lead strontium zirconium titanate substrate ((+)Ag and (−)Ag, respectively). The effects of a thickness extensional (TE) and radial extensional (RE) vibration, by resonance oscillation, on the catalytic activity were studied. With the TE mode at 10 MHz, the activation energy of ethanol oxidation on (+)Ag was different from that on (−)Ag. The surface potential varied negatively for (+)Ag and positively for (−)Ag and a threshold energy for photoelectric emission from (+)Ag shifted to lower energy. With the RE mode at 80 kHz, the activation energy of ethanol oxidation was the same between the (+) and (−)Ag surface and there was little change in the surface potential and photoelectric emission behavior.

Ruthenium oxide supported on barium titanates (Ba6Ti17O40, Ba4Ti13O30, BaTi4O9 and Ba2Ti9O20) was employed as a photocatalyst for water decomposition. The RuCl3-impregnated titanates were subjected to either reduction or reduction–oxidation. High-resolution electron microscopic images demonstrated that ruthenium metal and ruthenium oxides were uniformly dispersed on BaTi4O9 with an average particle size of 2.6 nm. Similar uniform ruthenium oxide dispersions were observed for the other barium titanates; the average particle sizes were 4.7 nm for Ba6Ti17O40, 2.3 nm for Ba4Ti13O30, and 4.4 nm for Ba2Ti9O20. Particle size distributions were narrower for BaTi4O9 and Ba4Ti13O30, and slightly larger for Ba6Ti17O40 and Ba2Ti9O20. Stoichiometric production of oxygen and hydrogen occurred for a RuO2/BaTi4O9 photocatalyst. A small amount of hydrogen and no oxygen were produced from the other barium titanates (Ba6Ti17O40, Ba4Ti13O30 and Ba2Ti9O20) combined with ruthenium oxides. EPR spectra at 77 K in He or O2 with UV irradiation demonstrated that a strong signal, assigned to a surface O- radical, appeared for BaTi4O9 but not for the other barium titanates. These produced small complicated signals, indicating that only BaTi4O9 has a high efficiency for photoexcited charge formation. Raman spectra showed that a strong single peak at a high wavenumber of 860 cm-1, characteristic of BaTi4O9, was absent in the rest of the barium titanates. The different photocatalytic properties among these titanates are discussed on the basis of structure differences of the barium titanates, and the presence of internal fields; a long Ti–O bond in the distorted TiO6 octahedra is proposed to be important in photocatalysis.

We show that spinodal decomposition under layer by layer crystal growth condition leads to characteristic quasi-one-dimensional nano-structures in dilute magnetic semiconductors (DMS). It is found that the DMS systems can form rather large clusters with highly anisotropic shape even for low concentrations. It is suggested that the blocking phenomena in the super-paramagnetism, the magnetic dipole–dipole interaction and the network of the one-dimensional structures should be considered to understand the magnetism in DMS. Based on the present simulations, we propose that the delta-doping method can be effective approach to realize high Curie temperature.