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Glycerophosphodiester phosphodiesterase (GDPD; EC 3.1.4.46) is involved in plant phosphate (Pi) utilization and its expression is upregulated under phosphorus (P)‐deficient conditions. Although rice was grown under P‐sufficient conditions, the transcript levels of specific OsGDPD were upregulated in mature rice leaf blades (LB) in elevated CO2 (eCO2) environments.Expression and subcellular localization of GDPD, and contents of Pi, sugar phosphates and carbohydrates were analysed to clarify the physiological function of GDPD in rice under eCO2.Under eCO2, expression of specific OsGDPD increased only in mature rice LB in which low Pi concentrations were observed. Moreover, eCO2‐induced OsGDPD2 and OsGDPD3 were localized in the plastid, indicating that GDPD2 and GDPD3 may be related to plastidic functions, such as carbon assimilation. Although rice LB contained more carbohydrates under eCO2 than under ambient CO2, the phosphoglucose content decreased under eCO2, suggesting that the need for excess phosphoglucose to synthesize carbohydrates under eCO2 causes a local Pi deficiency. Furthermore, we confirmed that glycerol‐3‐phosphate produced by the catalysis of GDPD from glycerophosphodiester contributes to carbohydrate accumulation in rice LB.Our findings suggest that local Pi deficiency due to excess carbohydrate accumulation under eCO2 influences GDPD to enhance glycerophosphodiester hydrolysis. [ABSTRACT FROM AUTHOR]

We study electrical spin injection and detection in n-Ge across Fe3Si/n+-Ge Schottky tunnel barriers. Spin-accumulation signals detected electrically by the three-terminal Hanle-effect measurements have large temperature dependence, and the spin signals disappear at around 200 K. We find that the temperature variation in the spin signals is strongly related to that in the interface resistance of the Fe3Si/n+-Ge contacts. We also observe marked reduction in nonlocal spin-valve signals with increasing temperature in the four-terminal device with almost the same Fe3Si/n+-Ge/n-Ge heterostructure. Note that the nonlocal spin signals depend on not only the measurement temperature but also on the electrical characteristics of the spin injector. Considering the results of three-terminal and four-terminal measurements, we conclude that temperature dependence of the spin signals in our Fe3Si/n+-Ge/n-Ge devices is governed by the electrical characteristics of the spin injector. This study means that it is necessary to consider the effective Schottky-tunnel contacts with the stability on temperature variations for next-generation Ge-based spintronic applications. [ABSTRACT FROM AUTHOR]

The chemical states of Fe and Pt in in situ annealed L10 structured FePt nanodots formed by self-assembled nanodot deposition method have been systematically investigated by angle resolved x-ray photoelectron spectroscopy. From the Fe3p and the Pt4f core level x-ray photoelectron (XP) spectra, it is evident that both the Fe and Pt of the nanodots were oxidized in the as-grown state. After the in situ annealing under high vacuum, a peak corresponding to metallic Fe begins to appear, and subsequently the metallic peak fraction increased with the increase in the annealing temperature. In line with this, the peak fraction of the respective oxides is drastically decreased. Irrespective of the annealing temperatures, it is inferred from the intensity of the XP spectrum that the Fe atom of the FePt nanodots is highly prone to oxidation than the Pt atom. Nevertheless, the valence band spectra of the as-grown FePt nanodot film clearly depict the presence of metallic Fe–Pt alloy. We would like to explain the results of the core level and valence band XP spectra as follows: only the peripheral Fe and Pt atoms of the as-formed FePt nanodots are bonded to the oxygen of the cosputtered SiO2 matrix, whereas the metallic core of the as-formed FePt nanodots is always preserved. The very good vacuum ambient during postannealing highly promotes the dissociation of oxygen from the metal oxides via reduction reaction. This results into an increase in the fraction of metallic Fe and Pt at the periphery of FePt nanodots and the formation of high quality SiO2 matrix after annealing. Similar results were also observed for the monatomic W as well as Pt nanodots embedded in SiO2 matrix. Hence, this simple, rather effective method of in situ annealing of metal dots dispersed in an insulating matrix can be readily employed in the fabrication of high-density nanodot memory devices. [ABSTRACT FROM AUTHOR]

Electrical and structural properties of polycrystalline silicon germanium (poly-SiGe) films fabricated by pulsed-laser annealing were investigated. Observation of laser-induced melt-regrowth of SiGe films using transient conductance measurement revealed that the melt depth and the crystallization velocity increased as Ge concentration increased. The increase of the crystallization velocity resulted in increase of the average size of crystalline grains from 66 to 120 nm at the laser energy density of 360 mJ/cm2 with increasing Ge concentration from 0 to 60%. The crystalline volume ratio obtained by reflectivity spectra in the ultraviolet region also increased from 0.83 to 1.0. Numerical analysis revealed that the density of electrically active defects decreased from 3.5×1018 to 1.1×1018 cm-3 as Ge concentration increased from 0 to 80%. The density of defect states of Si0.8Ge0.2 films were reduced from 3.5×1018 to 1.9×1018 cm-3 by 13.56-MHz hydrogen plasma treatment at 250 °C, 30 W, and 130 Pa for 30 s. However, the plasma treatment did not reduce the defect density for Si0.4Ge0.6 and Si0.2Ge0.8 films. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Solid-phase crystallization of Si[sub 1-x]Ge[sub x] (x=0-1.0) alloy layers deposited on a Si (100) substrate was investigated by ellipsometric spectroscopy. From a dispersion analysis of dielectric spectra, we deduced a crystallinity corresponding to the degree of average lattice alignment of the composed polycrystalline Si[sub 1-x]Ge[sub x] layers and investigated the dynamical change in crystallinity during crystallization. We found that the crystallinity and crystallization temperature (T[sub C]) rapidly decreased with increasing Ge concentration (x). When x was small (=0-0.3), the highest crystallinity was ∼0.8 of that for single crystals while the lowest one was considerably below 0.6 when x>0.8. Moreover, the crystallinity decreased with increasing temperature above T[sub C]. We investigated the nucleation rate during crystallization and found that the decrease in crystallinity at both large Ge concentration and high temperature can be explained by a trade-off between the nucleation and crystallization rates; nucleation was dominant under these conditions. An overview of the crystallinity of solid-phase crystallized Si[sub 1-x]Ge[sub x] alloy layers is provided. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Provides information on a study that examined the limited-area molecular-beam epitaxial growth of Si[sub1-x]Ge[subx] films on a silicon substrate with patterned SiO[sub2] in order to eliminate misfit dislocations in Si[sub1-x]Ge[subx]/silicon heterostructures. Methodology of the study; Results and discussion on the study.

Investigates low-temperature formation of a silicon-on-insulator structure by a solid-phase process. Details on the experiments; Experimental results; Conclusion.

We demonstrate high-quality epitaxial growth of Heusler alloy Co2FeSi on Ge(111) by molecular beam epitaxy (MBE) at 200 °C. Even for growth at such a low temperature, L21-ordered crystal structure is formed and highly uniform magnetic environments around the Fe sites are realized, by transmission electron diffraction and conversion electron Mössbauer spectroscopy, respectively. We also find that the magnetic moment reaches 5.37 μB/ f.u., which is the highest value in thin-film Co2FeSi samples reported. [ABSTRACT FROM AUTHOR]

We study magnetic properties of epitaxial Fe3Si layers grown on Ge(111) with atomically flat interfaces. An unexpected uniaxial magnetic anisotropy is observed in the film plane for all as-grown samples, and the direction of the uniaxial easy axis is different for each of these samples. By postgrowth annealing, surprisingly, the random orientation of the uniaxial easy axis is aligned to a direction along about [011], together with a reduction in the saturation magnetization. We discuss a possible mechanism of the variation in the magnetic properties after the annealing. [ABSTRACT FROM AUTHOR]

Determines the deformation of silicon surface under ultra high vacuum (UHV). Use of new crystal growth techniques of silicon molecular-beam epitaxy to cause homoepitaxy and heteroepitaxy; Comparison of the heating characteristics in UHV with that in inert gases; Investigation of the surface melting phenomena at the face-centered cubic crystals.

We demonstrate large-area (~600 μm), (111)-oriented, and high-crystallinity, i.e., pseudo-singlecrystalline, germanium (Ge) films at 275°C, where the temperature is lower than the softening temperature of a flexible substrate. A modulated gold-induced layer exchange crystallization method with an atomic-layer deposited Al2O3 barrier and amorphous-Ge/Au multilayers is established. From the Raman measurements, we can judge that the crystallinity of the obtained Ge films is higher than those grown by aluminum-induced-crystallization methods. Even on a flexible substrate, the pseudo-single-crystalline Ge films for the circuit with thin-film transistor arrays can be achieved, leading to high-performance flexible electronics based on an inorganic-semiconductor channel. [ABSTRACT FROM AUTHOR]

To produce high-performance devices on flexible plastic substrates, it is essential to form Ge-based group IV semiconductors on insulating substrates at low temperatures (≤250 °C). We have developed a technique for solid phase crystallization of amorphous GeSn (≤220 °C) enhanced by Sn doping, and combined with a seeding technique induced by Sn melting (250 °C). This combination produces lateral crystallization of amorphous GeSn from seed arrays with no incubation time. As a result, extremely high growth velocities at 220 °C, depending on Sn concentration, e.g., 0.13μm/h (14% Sn) and 1100μm/h (23% Sn), are achieved. These velocities are 104-108 times higher than that of pure Ge. This technique enables growth of crystalline GeSn island arrays (diameters: 50-150μm) at low temperatures (≤250 °C) at controlled positions on insulating substrates. [ABSTRACT FROM AUTHOR]

We study high-quality Co2FeSi1-xAlx Heusler compound/Si (0 ≤ ≤ < 1) heterointerfaces for silicon (Si)-based spintronic applications. In thermal treatment conditions, the magnetic and structural stabilities of the Co2FeSi1-xAlx/Si heterointerfaces are improved with increasing x in Co2FeSi1-xAlx. Compared with L2¹-ordered Co2FeSi/Si, B2-ordered Co2FeAl/Si can suppress the diffusion of Si atoms into the Heusler-compound structure. This experimental study will provide an important knowledge for applications in Si-based spin transistors with metallic source/drain contacts. [ABSTRACT FROM AUTHOR]

This study demonstrates that by using a sulfur (S) treatment on the Ge surface, a reduction in Fermi level pinning can reproducibly be achieved at atomically matched metal/Ge(111) interfaces. The Schottky barrier height for p-type Ge can be controlled by changing the metal work function despite the metal/Ge junctions. The results indicate that the combination of atomic-arrangement matching and S treatment can remove extrinsic factors influencing Fermi level pinning at metal/Ge interfaces. [ABSTRACT FROM AUTHOR]

Summary: Previous studies on the association between uric acid and bone mineral density yielded conflicting results. In this study, we demonstrated positive association between uric acid and lumbar spine bone mineral density in peri- and postmenopausal Japanese women. Further research is needed to elucidate the underlying mechanism. Introduction: Oxidative stress has been implicated in the pathogenesis of osteoporosis. Uric acid, a potent antioxidant substance, has been associated with bone mineral density but previous studies have yielded conflicting results. The objective of the study was to examine the association between serum uric acid and lumbar spine bone mineral density (BMD). Methods: This was a retrospective analysis of medical records of 615 women, aged 45-75 years, who had lumbar spine BMD measurement by dual-energy X-ray absorptiometry as a part of health checkup from August 2011 to July 2012. Results: Mean serum uric acid level was 4.7 mg/dL. Serum uric acid level was positively and significantly associated with lumbar spine BMD independent of age, body mass index, smoking, drinking, physical activity, years after menopause, diabetes mellitus, hypertension, serum calcium, estimated glomerular filtration rate, plasma C-reactive protein, and serum alkaline phosphatase (standardized beta = 0.078, p = 0.049). Uric acid rapidly increased until the age of 60 years, and then decelerated but continued to increase thereafter. The association between lumbar spine BMD and uric acid remained significantly positive after excluding women older than 60 years. Conclusion: The present study showed that higher uric acid levels were linearly associated with higher lumbar spine BMD in peri- and postmenopausal Japanese women. Further research is needed to elucidate the underlying mechanism of the association between uric acid and BMD. [ABSTRACT FROM AUTHOR]

Using room-temperature molecular beam epitaxy on Si(111), we demonstrate Heusler-alloy bilayers consisting of L21-Co2FeSi (CFS) and D03-Fe3Si (FS). By fabricating lateral spin valves with L21-CFS and D03-FS electrodes, we can see ideal spin signals even though we use one L21-CFS as a spin injector and another D03-FS as a spin detector. The difference in the spin absorption between L21-CFS and D03-FS can also be examined, and we find that the spin resistance of D03-FS is larger than that of L21-CFS. This work will be useful for understanding spin transport in lateral spin-valve devices with different Heusler-alloy electrodes. [ABSTRACT FROM AUTHOR]

We show a marked effect of magnetic domain structure in an epitaxial CoFe contact on spin accumulation signals in Si devices detected by three-terminal Hanle effect measurements. Experimental results indicate that magnetic domain structures cause large discrepancies in the estimation of spin lifetime and bias-current dependence of the spin accumulation signal. By introducing the domain walls in CoFe contact, spin accumulation signals are reduced, which is caused by the lateral spin transport in the Si channel. Thus, to understand precisely the physical properties of Si spintronic devices, it is important to take into account the control of magnetic domain structure in the contacts. [ABSTRACT FROM AUTHOR]

In this study, we conducted two experiments on visual cognitive performance in reading an on-board information device. Experiment 1: The relation between the gazing time needed for reading and the number of Kanji characters displayed was investigated, as the number of characters was changed in three steps. The gazing time was divided into preparation time and information processing time. The unit information processing speed was calculated from the amount of information read divided by the information processing time. Experiment 2: The character size was changed between three conditions (large, middle and small), and visual distance was changed between two conditions (700 and 2000 mm). The gazing time was similar to that in experiment 1. The results from these experiments are applicable to the design of user-friendly information devices, taking into account the user's age. [ABSTRACT FROM AUTHOR]

Purpose: To investigate whether saline pushing after contrast material improves hepatic vascular and parenchymal enhancement, and to determine whether this technique permits decreased contrast material concentration. Material and Methods: 120 patients who underwent hepatic multidetector computed tomography were divided randomly into four groups (Groups A-D): receiving 100 ml of contrast material (300 mgI/ml) only (A) or with 50 ml of saline solution (B); or 100 ml of contrast material (350 mgI/ml) only (C) or with 50 ml of saline solution (D). Computed tomography (CT) values of the aorta in the arterial phase, the portal vein in the portal venous inflow phase, and the liver in the hepatic phase were measured. Visualization of the hepatic artery and the portal vein by 3D CT angiography was evaluated as well. Results: Although the enhancement values of the aorta were not improved significantly with saline pushing, they continued at a high level to the latter slices with saline pushing. The enhancement value of the portal vein increased significantly and CT portography was improved with saline pushing. The enhancement value of the liver was not improved significantly using saline pushing. In a comparison between groups B and C, the enhancement values of the aorta and portal vein and the visualization of CT arteriography and portography were not statistically different. Conclusion: The saline pushing technique can contribute to a decrease in contrast material concentration for 3D CT arteriography and portography. [ABSTRACT FROM AUTHOR]

Abstract Calcitonin (CT), a calcium-regulating hormone, lowers the calcium level in serum by inhibiting bone resorption. Because CT may play a role in the pathogenesis of osteoporosis, genetic variations in or adjacent to the CT gene may be associated with variations in bone mineral density (BMD). The present study examined the correlation between a dinucleotide (cytosine-adenine; CA) repeat polymorphism at the CT locus and BMD in 311 Japanese postmenopausal women (mean age, 64.1 years). Seven alleles were present in this population; each allele contained 10, 11, 16, 17, 18, 19, or 20 CA repeats. Thus, we designated the respective genotypes A10, A11, A16, A17, A18, A19, and A20. The A10 and A17 alleles were the predominant alleles in the population studied. Z scores (a parameter representing deviation from the age-specific weight-adjusted average BMD) were compared between individuals that possessed one or two alleles of each genotype and those that did not possess the allele. Subjects who possessed one or two Al0 alleles had lower BMD Z scores than those who did not (lumbar 2-4 BMD Z score; -0.148 + 1.23 vs 0.182 + 1.54; P = 0.04). No ... [ABSTRACT FROM AUTHOR]

A novel variation of the estrogen receptor-alpha (ERalpha) gene was identified by polymerase chain reaction-single-strand conformational polymorphism (PCR-SSCP). It is one base substitution in codon 325 (CCC [allele M] to CCG [allele m]) in exon 4 of the human ERalpha gene. This substitution did not cause an amino acid change. We categorized 306 unrelated Japanese postmenopausal women into three genotypes: MM, Mm, and mm; the frequency of each genotype was 26.5%, 43.1%, and 30.4%, respectively. Then, the association of this polymorphism with bone mineral density (BMD) of lumbar spine and bone-calcium metabolic markers was studied. There was no significant difference in BMD of the lumbar spine or most of the bone metabolic markers. However, the urinary calcium (Ca) excretion ratio (u-Ca/Cre) corrected by creatinine was significantly lower in the genotype mm group compared with the genotype MM group (MM vs mm, 0.247 +/-0.158 vs 0.200 +/- 0.105; P < 0.05). We examined the relationship of restriction fragment length polymorphisms (RFLPs) (PvuII, XbaI) in intron 1 and the polymorphism in exon 4. The frequency of genotype MM was higher in the genotype PPxx, which was reported to be associated with lower BMD in the same population of Japanese postmenopausal women. The ER polymorphism identified in this study might be related to some biological mechanisms that regulate calcium metabolism. [ABSTRACT FROM AUTHOR]

The pathogenesis of osteoporosis is controlled by genetic and environmental factors. Considering the high prevalence of osteoporosis in homocystinuria, abnormal homocysteine metabolism would contribute to the pathogenesis of osteoporosis. It is known that the polymorphism of methylenetetrahydrofolate reductase (MTHFR), the enzyme catalyzing the reduction of 5, 10-methylenetetrahydrofolate to 5-methyltetrahydrofolate, correlates with hyperhomocysteinemia. In this study, we examined the association of this polymorphism with bone mineral density (BMD). BMD was measured by dual-energy X-ray absorptiometry (DXA) in 307 postmenopausal women. MTHFR A/V polymorphism was analyzed using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). We compared BMD, clinical characteristics, and bone metabolic markers among MTHFR groups (AA, AV, VV). The groups did not differ in terms of baseline data. The values of lumbar spine BMD and total body BMD were as follows: lumbar spine: AA, 0.91 +/- 0.18, AV, 0.88 +/- 0.16, VV, 0.84 +/- 0.14 g/cm(2); total body: AA, 0.97 +/- 0.11, AV, 0.96 +/- 0.11, VV, 0.93 +/- 0.09 g/cm(2). In the VV genotype, lumbar spine BMD values were significantly lower than those of the women with the AA genotype (P = 0.016) and total body BMD was significantly lower than those of the women with AA genotype (P = 0.03) and AV genotype (P = 0.04). This is the first report that suggests that the VV genotype of MTHFR is one of the genetic risk factors for low BMD. [ABSTRACT FROM AUTHOR]