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We describe three cases of early- (cases 1–3, 28–39 years) and one of late-onset (case 4, 76 years) Alzheimer's disease (AD) with 'cotton wool' plaques (CWPs) but without a family history indicating autosomal dominant inheritance. The early-onset cases, but not the late-onset case, showed remarkable aggression, disinhibition, and impulsiveness. Spastic paraparesis was observed in only one early-onset case. Hematoxylin-eosin-stained sections showed numerous CWPs, especially in the temporal cortex, in all cases. Bielschowsky-stained sections showed neurofibrillary tangles and minor neuritic changes surrounding the CWPs in three cases, but not in case 2. Gallyas-Braak-stained sections showed weak argyrophilia in homogeneous material of the CWPs in cases 2 and 4. Quantitative analysis demonstrated that Aβ42 was deposited more predominantly than Aβ40 in three cases. However, in case 2, approximately twice as much Aβ40 as Aβ42 was deposited. Tau immunostaining demonstrated neuritic changes in three cases, but not in case 2. α-Synuclein-positive Lewy bodies (LBs) and astrocytic lesions containing non-Aβ component of AD amyloid (NAC), a central fragment of α-synuclein, were found in case 3. In conclusion, (1) a frontal lobe syndrome-like personality change may be one of the characteristic clinical features of early-onset CWP-AD, (2) the deposition pattern of Aβ40 and Aβ42 in CWP-AD is more variable than that of presenilin-1-linked cases, (3) Aβ deposition can result in development of dementia without tau pathology, and (4) CWP-AD with LBs and several other neurodegenerative disorders with LBs share a common process involving α-synuclein and NAC deposition. [ABSTRACT FROM AUTHOR]

Plasma copolymerization of hexamethyldisiloxane (HMDSO,(CH3)3-Si-O-Si-(CH3)3) and C4F8 was performed using an RF plasma enhanced chemical vapor deposition method for application to low dielectric constant intermetal dielectrics. Structure of the films was investigated by X-ray photoelectron spectroscopy and Fourier transform infrared (FT-IR) spectroscopy. The film composition was controlled gradually from fluorinated carbon to organic siloxane by changing the mixing ratio of HMDSO/Ar. Dielectric constant of the films ranged from 2–3.3. Thermal stability of the films, which was characterized by intensity loss of IR absorbance peak around 1000–1500 cm−1 corresponding to C-F n, Si-O-Si and Si-(CH2)n-Si bonds, was inferior to that from C2F4/HMDSO/Ar. In situ gasphase FT-IR spectroscopy revealed that there was a marked difference between the gas phase of C4F8/HMDSO/Ar and that of C2F4/HMDSO/Ar discharges. The IR spectrum of the former combination plasma contained a peak at 1250 cm−1 with full width at half maximum as large as 150 cm−1, which suggests that fluorocarbon particles and/or dusts are formed in the plasma. This suggests also that deposition precursors are not only CF n ( n = 1, 2, and 3) but also larger precursors such as C xF y ( x > 1, y < 2 x + 2) in C4F8/HMDSO/Ar discharges, which is presumably the cause of difference in thermal stability of the films prepared from C4F8/HMDSO/Ar and C2F4/HMDSO/Ar mixtures. [ABSTRACT FROM AUTHOR]

Fluorinated amorphous carbon films were prepared from tetrafluoroethylene (TFE; C2F4) and tetraisocyanatesilane (TICS; Si(NCO)4) using an RF plasma enhanced chemical vapor deposition method for the purpose of application to inter layer low permittivity films used in large scale integrated circuits. Structure of the deposited films was investigated by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. Adhesion characteristics were examined by a tape-peel method. Permittivity of the films was investigated from capacitance measurement on metal-insulator-semiconductor structure. The structural analysis revealed that the deposited films contained imide-like group $$( = N---C = {\text{O}})$$ in spite of the fact that TICS molecules contained isocyanate group $$(---N = C = {\text{O}})$$ . The films deposited under the flow ratio TICS/(TFE + TICS) = 70% showed permittivity of 2.3, good adhesion on silicon substrates, and higher thermal stability than the films deposited without TICS. [ABSTRACT FROM AUTHOR]

Experiments of fine-particle plasma have been performed using a drop experiment facility in order to analyze the ordering and behavior of fine particles under microgravity and during the change of gravitational conditions. Aligned fine particles in the radial directions were observed under microgravity, although they were aligned in the vertical direction under gravity. It has been suggested that the vertical alignment of fine particles under gravity is caused by the mutual influence between positive ion flow and negative fine particles following the deformation of plasma. [ABSTRACT FROM AUTHOR]