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Abstract: This paper presents a new method to machine flexible plates with high accuracy and high productivity. Precision steel plates are finished conventionally by face milling with electro-magnetic chucks. It is difficult to correct flatness of the flexible plates, because they deform to fit the chuck surfaces when chucked. To solve this problem, the authors have tried simultaneous double-sided milling, but this causes the regenerative chatter vibration. Thus, the new method is proposed and verified to suppress this chatter vibration, in which the regenerative effects on both sides are cancelled out by rotating the two milling cutters at different speeds. [Copyright &y& Elsevier]

Abstract: We exposed crystalline Si (C-Si) substrates to a NH3 plasma by the method of plasma enhanced chemical vapor deposition (PECVD) and the Si substrates were nitrided at a nitridation temperature, T n, between 300 and 600°C. The nitrided layers were grown directly on n-type C-Si substrates with high resistivity for measurements of electron resonance (ESR) and Fourier transform infrared (FTIR) absorption. The intensity of the N–H IR bending band increased with increasing T n up to 450°C, and then decreased again with a further increasing in T n. We found a strong correlation between the change in the ESR spin density, N s, and that in the N–H bending intensity, which was obtained from the spectral intensity at around 1200cm−1. Furthermore, incorporation of N atoms in amorphous Si x N y layers may improve the structural property at T n =450°C for various insulating applications. In addition, we found that the atomic densities and/or composition of a-Si x N y may decrease the BHF etch rate. [Copyright &y& Elsevier]

Aim: To investigate whether contrast-enhanced (CE)-magnetic resonance imaging (MRI) improves identification of implantation site of ectopic pregnancy.Materials and Methods: This retrospective study enrolled 63 patients in whom implantation sites had been confirmed at histopathology. Two expert radiologists for gynaecological imaging and two inexpert radiologists independently reviewed non-CE MRI and a combination of non-CE and CE-MRI (non-CE+CE-MRI), then determined implantation site with a confidence level. The following MRI features were also evaluated: extrauterine gestational sac (GS)-like structure (shape, signal intensities at T1-weighted imaging [WI], T2WI, and diffusion-weighted imaging [DWI], presence of the three rings appearance, and distinct low intensity areas at T2WI, presence of tree or dot-like components, degree of contrast enhancement), fallopian tube (dilatation, dilatation with haematoma, degree of contrast enhancement, enhanced components within the tube), and ascites. These findings were compared for non-CE and non-CE+CE-MRI data, and for expert and inexpert groups.Results: The expert group identified implantation sites correctly in 58/63 (92%) cases for non-CE and non-CE+CE-MRI. In the inexpert group, the correct identification was improved from 54/63 (86%) using non-CE MRI to 58/63 (92%) using non-CE+CE-MRI, but was not significant (p=0.29). In comparison between non-CE and non-CE+CE-MRI, dilation of the fallopian tubes was observed more frequently (p=0.004) and the confidence level was elevated significantly in the non-CE+CE-MRI (p<0.0001) in the inexpert group. Intergroup comparison revealed that confidence level was significantly higher in the expert group than in the inexpert group using non-CE MRI (p<0.0001), although the difference was not significant at non-CE+CE MRI (p=0.49).Conclusion: CE-MRI did not significantly improve correct identification of ectopic pregnancy implantation sites, although the addition of contrast enhancement did enable inexpert radiologists to diagnose confidently. [ABSTRACT FROM AUTHOR]

Abstract: The structural properties of polycrystalline silicon films, prepared by plasma enhanced chemical vapor deposition system, with different flow rates of SiH4/SiF4 mixtures at 300°C were investigated. This study indicates that the low hydrogen coverage on the growing surface, under optimum fluorine radicals, will be leaded to an improvement of crystallized area as compared with case of high hydrogen coverage surface. Moreover, the studies of the role of SiH4 and SiF4 radicals show that the SiH4 radicals are important in the nucleation and growth of grains. However, SiF4 radicals are effective in the structural change of grain boundaries regions and by this way, in the present system, establish the growth of grains under the dominant 〈110〉 direction. The stress investigation indicates that addition of high flow rate of SiF4 in amorphous film, results in the nearly stress free films. Finally, we found that the changes in g-value reflect the changes in the intrinsic compressive and tensile stress in the both polycrystalline and amorphous silicon films. [Copyright &y& Elsevier]

Abstract: The structural properties of polycrystalline silicon films, prepared by plasma enhanced chemical vapor deposition system, with different flow rates of SiH4/SiF4 mixtures at 300°C were investigated. This study indicates that the low hydrogen coverage on the growing surface, under optimum fluorine radicals, will be leaded to an improvement of crystallized area as compared with case of high hydrogen coverage surface. Moreover, the studies of the role of SiH4 and SiF4 radicals show that the SiH4 radicals are important in the nucleation and growth of grains. However, SiF4 radicals are effective in the structural change of grain boundaries regions and by this way, in the present system, establish the growth of grains under the dominant 〈110〉 direction. The stress investigation indicates that addition of high flow rate of SiF4 in amorphous film, results in the nearly stress free films. Finally, we found that the changes in g-value reflect the changes in the intrinsic compressive and tensile stress in the both polycrystalline and amorphous silicon films. [Copyright &y& Elsevier]

Amorphous silicon oxynitride, a-SiOxNy, layers were prepared by nitridation of 7-nm thick thermally grown silicon dioxide, a-SiO2, layers on n-type crystalline Si substrates, in NH3 plasma with different temperatures (TP=300–500 °C). The compositional and structural properties for the a-SiOxNy layers were examined using current–voltage (I–V), capacitance–voltage (C–V), electron spin resonance (ESR), Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy and Fourier transform infrared measurements. We found a strong correlation between the change in the ESR spin density and that in the C–V characteristics with varying TP. These results were interpreted as indicating a change in the compressive strain. The I–V characteristics showed that the breakdown strength monotonically decreased with increasing TP. In the distribution of the constituent atoms, the AES profiles were roughly independent of TP. The changes in the 800 and 1070 cm−1 IR absorption bands were also examined based on those in the compressive strain, as well as a proposal for interpreting the ESR and C–V results. [Copyright &y& Elsevier]

Abstract: We previously demonstrated that the peptidergic neurotransmitter pituitary adenylate cyclase-activating polypeptide (PACAP) affects the autonomic system and contributes to the control of metabolic and cardiovascular functions. Previous studies have demonstrated the importance of centrally-mediated sympathetic effects of leptin for obesity-related hypertension. Here we tested whether PACAP signaling in the brain is implicated in leptin-induced sympathetic excitation and appetite suppression. In anesthetized mice, intracerebroventricular (ICV) pre-treatment with PACAP6-38, an antagonist of the PACAP receptors (PAC1-R and VPAC2), inhibited the increase in white adipose tissue sympathetic nerve activity (WAT-SNA) produced by ICV leptin (2μg). In contrast, leptin-induced stimulation of renal sympathetic nerve activity (RSNA) was not affected by ICV pre-treatment with PACAP6-38. Moreover, in PACAP-deficient (Adcyap1−/−) mice, ICV leptin-induced WAT-SNA increase was impaired, whereas RSNA response was preserved. The reductions in food intake and body weight evoked by ICV leptin were attenuated in Adcyap1−/− mice. Our data suggest that hypothalamic PACAP signaling plays a key role in the control by leptin of feeding behavior and lipocatabolic sympathetic outflow, but spares the renal sympathetic traffic. [Copyright &y& Elsevier]