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Background: There have been many reports that caries susceptibility of children with Down syndrome is lower than that of unaffected children. However, the perspectives on the factor of caries susceptibility have not yet been unified due to its diversity. This study aimed at comparing children with Down syndrome with unaffected children regarding the biochemical analysis and the histological observations with increasing depths from the surface of deciduous teeth. Methods: Atomic concentrations of calcium and phosphorus at the core regions of the enamel prism were analyzed using an electron probe microanalyzer. Histological observations were simultaneously conducted. In addition to the subjective comparisons, percentages of the enamel prism cores (interprismatic substance area ratio) were also calculated. Results: Regarding calcium and phosphorus concentrations or calcium/phosphorus ratio, there were no significant differences between the two groups at any of the layers. Additionally, there was no significant change in either group with increasing depths from surface. The findings of enamel surface revealed three-dimensionality in unaffected children, while smoothness in children with Down syndrome. In children with Down syndrome, the outline of enamel prisms showed some of which formed incompletely. Enamel prism cores were similar to the interprismatic substance in terms of crystal structure. Interprismatic substance area ratio of children with Down syndrome was lower than that of unaffected children in all the layers except at 150 μm and 250 μm. Conclusion: In this study, the deciduous canine enamel of children with Down syndrome was thought to include more organic material than that of unaffected children.

The novel use of SiCN underneath TEOS oxide as a bonding surface in the wafer bonding of Backside-illuminated (BSI) sensor is proposed and the mechanism of void control by SiCN is clarified. In general, high-temperature processing results in generating voids between the wafer interfaces after bonding due to the release of high-pressure H 2 O contained in TEOS. In the proposed mechanism, the SiCN exposed to high-temperature H 2 O is oxidized thereby preventing the emission of high-pressure H 2 O gas. This paper analyzes the role of SiCN in this mechanism.

Background Systemic disturbance during the fetal and postnatal periods in disabled children may affect the formation and mineralization of deciduous tooth enamel. Aim To reveal differences in the status of mineralization in the surface and inner layers of deciduous tooth enamel between children with cerebral palsy (CP), those with Down syndrome (DS), and controls. Methods Using extracted deciduous teeth obtained from CP children (5 teeth), DS children (5 teeth), and control children (11 teeth), fluoride and magnesium concentrations, used as mineralization parameters, were measured in three regions of the enamel at different depths: the enamel surface (ES), neonatal line (NL), and dentino-enamel junction (DEJ). Results Fluoride concentration was significantly higher in the ES region than in the NL or DEJ region in all three groups. There was no significant correlation between type of disability and fluoride concentration. Magnesium concentration was significantly higher in the DEJ region than in the NL or ES region. A significant correlation was seen between type of disability and magnesium concentration. Conclusions Magnesium concentration was significantly higher in DS children than in control children, suggesting that DS children undergo poorer mineralization. Magnesium concentration tended to be higher in CP children than in control children.

A clear yield point was not seen in the tensile strength of the aluminum sintering body. As for the molding pressure, 170MPa was the upper limit value. Hardness, the radial crushing strength increased, but the oil content. As for the sintering temperature, 545°C were the upper limit values. Hardness, the radial crushing strength increased, but the oil content increased to 545°C, too. The friction examination of molding pressure 170MPa showed limit PV value 6.46MPa.m/s. The friction examination of sintering temperature 545°C showed aspect pressure 17MPa. The life examination maintained friction temperature to approximately 40°C until 30hours.

The tests for sliding characteristic of sintered aluminum with retained oil for sliding bearing were conducted . The sintered aluminum materials blended of silicon with 40wt% weight in maximum were made for experiments. Results obtained are as follows. There was the relation among the oil content, the radial crushing strength and the hardness. There was the limitation of mean grain size and weight fraction of silicon for the higher quantity of oil and the higher mechanical properties. In that condition, the hardness increased with the quantity of retained oil in subsurface of tested rings.

Machine designers are sometimes confronted with high contact pressure conditions which generate plastic deformation. However there is no clear design method for such severe condition. We investigate the contact condition in the high contact pressure by using a ball-on-glass disc type test. According to the test results, the following conclusions were obtained. 1) The ratio of calculating contact pressure and the hardness in consideration of working hardness, the number of the ratio is settled about 0.4 for any loading condition. 2) In the condition of high contact pressure generating plastic deformation, the contact pressure converges with constant value according to the work hardening behavior of material.

Activating mutations of the extracellular calcium (Ca2+e)-sensing receptor (CaR) gene, mostly in its extracellular domain, can cause both familial and sporadic hypoparathyroidism. We report a Japanese family with severe hypoparathyroidism with pretreatment serum calcium (Ca) levels of 4.9–5.9 mg/dL. The proband presented with a seizure at 6 days of age. Her older brother and mother, who had also experienced seizures and tetany, respectively, likewise had hypoparathyroidism. A heterozygous missense mutation substituting a cysteine for the phenylalanine normally present at codon 788 (F788C) was identified in the CaR’s fifth transmembrane domain and was shown to cosegregate with the disease. The mutation was absent in DNA from 50 control subjects. Analysis of the functional properties of the mutant receptor was carried out in transiently transfected HEK293 cells loaded with fura-2 by assessing Ca2+e-evoked increases in the cytosolic calcium concentration (Ca2+i). There was a leftward shift in the concentrati...

Precursors for CuZnO catalysts, with CuZn molar ratios in the range from 1000 to 0100, were prepared by two coprecipitation methods. These methods differ by the addition rate of a mixed Cu(NO3)2Zn(NO3)2 solution to a NaHCO3 solution. Characterisation by powder X-ray diffraction (PXRD), differential thermal analysis (DTA), thermal gravimetric analysis (TGA), FT-IR and UV/VIS spectroscopies indicated that the structure of precursors with CuZn ratios in the range of 3070 to 7030 depends greatly upon the addition rate of the mixed solution. Amorphous copper hydroxycarbonate and sodium zinc carbonate were formed prior to the various precursors such as malachite, aurichalcite and hydrozincite. The uZnO catalysts subsequently formed from the precursors showed the activity for steam reforming of methanol to vary with its composition. Based on the results of temperature programmed oxidation (TPO) with N2O and an infrared spectra of CO chemisorption, the TOF of the reaction is proposed to be associated with the surface of metallic Cu.

For characterization of the surface structure of metallic copper formed on the support, temperature programmed oxidation (TPO) with N2O was carried out over various Cu/ZnO catalysts. Four peaks of the N2 formation (α, β, γ and δ) were observed at 223, 400, 545 and 600 K in the TPO runs. The average copper crystallite size estimated from the sum of the amount of α- and β-peaks agreed fairly with those determined by X-ray diffraction and transmission electron microscopy. It was concluded that α- and β-peaks resulted from the oxidation of metallic copper atoms on the steps, corners and/ or defect sites, and on the flat sites of the surface of copper crystallites, respectively, while γ- and δ-peaks resulted from the bulk oxidation of copper.

One of the most challenging issues in the metal hard mask (MHM) process is controlling the residual stress in TiN mask. This becomes more important as the feature sizes of trenches and vias continue to shrink and the low k-value dielectrics are introduced to Cu interconnect. It is found that the deformation of trenches due to the residual stress in TiN results in Cu voids forming. To overcome this problem, the correlation between the residual stress and the film property of TiN has been investigated. The residual stress in TiN is found to strongly correlate with both the grain size and the crystal structure of TiN, and low residual stress in TiN is accomplished by suppressing the grain growth of TiN. By applying TiN that has a quite fine needle-like structure, the trench deformation can be suppressed and thus the gap filling is perfectly achieved. The MHM process using TiN film that has a needle-like structure is a promising technology for 32-nm node Cu interconnect and beyond.

The synthesis of [4,5,6,8-2H4][2.2]metacyclophane (8) was achieved starting with 2,4,5,6-tetrafluoroisophthalic acid in eight steps in 2% total yield. 1H{2H} and 13C{1H} NMR spectra of 8 showed that the deuterium atoms were introduced at the desired positions.

RuTa(N) film has been prepared by doping N in Ru-Ta alloy and investigated its use as a barrier layer against Cu diffusion in Cu interconnects. It was found that RuTa(N) has a poor barrier property against Cu in the BEOL process, since N in Ru-Ta alloy is desorbed and RuTa(N) is recrystallized by heat treatment. It was also shown that RuTa(N) has inferior reliability due to its poor wettability with Cu compared to RuTa. On the other hand, RuTa has both good barrier property and superior reliability performance. It is possible to apply RuTa single film as a barrier layer for Cu interconnects.

In order to control the characteristics of porogen-based porous SiOC film (k ≪ 2.5), we investigated its dependence on the wavelengths of ultraviolet (UV) light by using methods of FT-IR, TDS and nano-indentation. As a result, it was found that specific wavelengths of UV light strongly was effective to porous SiOC film production : porogen desorption, mechanical strength improvement, and reduction of the film damage. Vacuum ultraviolet (VUV) irradiation is necessary for porogen desorption. However, after porogen was removed from SiOC film, the energy of VUV irradiation was too high for porous SiOC film and this caused film damage. The energy of deep ultraviolet (DUV) irradiation was sufficient to improve mechanical strength. We propose that UV curing process should be a multi-step process consisting of VUV and DUV irradiation (Figure 1). The first step removes porogen using VUV irradiation. The second step forms robust porous SiOC film using DUV irradiation. A multi-step curing process was used to control the characteristics of porogen-based porous SiOC film.

Laser-induced-fluorescence spectroscopy has been applied to neon and helium-neon discharge plasmas in magnetic fields lower than 10 T. Disalignment-rate coefficients of the neon 2{ital p}{sub 2} and 2{ital p}{sub 7} atoms (2{ital p}{sup 5}3{ital p} configuration, Paschen notation) have been determined for neon and helium collisions in a field strength that is lower than the critical field at which the collision time is equal to the inverse Larmor frequency. The 2{ital p}{sub 7} atoms have rate coefficients independent of the magnetic-field strength, whereas the 2{ital p}{sub 2} atoms have a field-dependent rate coefficient for neon collisions.

Dual damascene Cu interconnects with Keff below 2.0 have been demonstrated for the first time. Air gaps between Cu lines were formed with a low K SiOC film in a carefully designed manner. CoWP cap layers were introduced to protect the Cu lines and to eliminate a dielectric liner layer. In addition, AGE (Air Gap Exclusion) was applied to solve crucial problems related to the air gaps. Keff of 1.9 was obtained at 65 nm design rule, which surpassed by far ITRS target (2.5~2.8) for hp 45. It was also confirmed that leakage current between lines was suppressed by the formation of the air gaps.

We have studied electromigration (EM) and stress-induced voiding (SV) behaviors based on our 90 nm-node Cu/low-k interconnect processes, and demonstrated successful improvement of the interconnect reliability. In EM study wide bimodal failure distribution was found only in the particular EM test structure. We identified that it caused by the lack of wettability between Cu and the barrier metal in the vias, and demonstrated that the optimization of the barrier metal thickness could suppress it. In SV behavior, we revealed a mechanism of the voiding under the vias that was due to the initial existence of the nuclei of the void before high temperature storage test. The failure mode was suppressed by optimizing preheat temperature of M2 barrier metal deposition.

The versatility of polymer-assisted enzymatic synthesis of non-natural and biologically significant glycolipid derivatives was demonstrated by constructing pseudo-ganglioside GM3 1 having the trisaccharide sequence Neu5Acα- (2→6)Galβ(1→4)Glc and a fluorescent labelled lysoGM3 2.

We developed a new 3-dimensionally(3d) stacked capacitor structure, a tunnel structured stacked capacitor cell (TSSC), for 64Mbit dRAMs. The TSSC with 2 tunnels realized improved reliability the same as that of the conventional stacked capacitor (STC) and a capacitance of 29 fF with a capacitor height of 0.25 µm because of side-wall electrode formation. The equivalent thickness of SiO2 for the oxide nitride oxide (ONO) is 7.8 nm, and the cell area is 1.8 µm2. The uniformity of the ONO inside the tunnel of the TSSC was confirmed except for the corner of the tunnel, while the thickness of the ONO is slightly greater at the corner. At the corner, the top oxide film of the ONO is slightly thicker than that at the other areas, and accordingly, the shape of the plate electrode at the corner becomes round. These shape effects lead to no generation of the local field concentration at the corner inside the tunnel. They are applied to the other 3d stacked capacitors which have generally been proposed.

In order to determine the stereoregularity of poly(2-vinylpyridine), 2-vinylpyridine-..beta..,..beta..-d/sub 2/ was synthesized. The /sup 1/H-NMR spectra of the deuterated polymer in D/sub 2/SO/sub 4/ and o-dichlorobenzene solutions showed three peaks, which were assigned to triad tacticities. Since the absorptions of heterotactic and syndiotactic triads of methine protons overlap those of methylene protons in nondeuterated polymers, only isotactic triad intensities can be obtained from the /sup 1/H-NMR spectra of nondeuterated poly(2-vinylpyridine). The /sup 13/C-NMR spectra of poly(2-vinylpyridine) were obtained in methanol and sulfuric acid solutions. In methanol solution the absorption was split into three groups, which cannot be explained by triads, and in sulfuric acid solution several peaks were observed. These splittings may be due to pentad tacticity. The results show that poly(2-vinylpyridine) obtained by radical polymerization is an atactic polymer.