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Dynamic viscoelastic properties and morphology of poly(methyl methacrylate) (PMMA)/poly(vinyl alcohol) (PVA) blend prepared by melt kneading was investigated. These solubility parameter values differ greatly. Two kinds of PVA with saponification degrees of 88 and 98 mol.% were used. Micrometre-order domains were observed by scanning electron microscopy for 88 mol.% PVA, whereas no clear domain was observed for 98 mol.%. Both the blends were incompatible systems because two loss modulus peaks based on PMMA and PVA were observed by dynamic mechanical analysis. The loss modulus peak based on the PMMA-rich phase was higher than that of pure PMMA; the increase of the corresponding glass transition temperature (Tg) caused by blending was more remarkable for 98 mol.% PVA than 88 mol.%. It was thought that the intermolecular interaction of OH group in PVA and carbonyl group in PMMA caused the increase in Tg, but no clear evidence of the interaction for the blend was observed by a Fourier transform infrared spectroscopic analysis. The poly(vinyl acetate)/PMMA blend was incompatible. The unsaponificated vinyl acetate unit in PVA decreased the interaction between PMMA and PVA. This is the reason why the effect of Tg rising was lower for 88 mol.% PVA than for 98 mol.%. [ABSTRACT FROM AUTHOR]

Purpose. To investigate the repeatability and reproducibility of intraocular pressure (IOP) and central corneal thickness (CCT) measurements using a noncontact tono/pachymeter (NT-530P) and to assess the correlation of CCT with IOP. Methods. Forty-six eyes of healthy volunteers were measured by two examiners. Three consecutive measurements per eye were performed. Repeatability was assessed using the coefficient of variation, and reproducibility was assessed using Bland-Altman plots. Linear correlations were used to determine agreement between CCT and noncorrected IOP and CCT and corrected IOP, which was calculated using a formula built into the NT-530P. Results. The coefficient of variation for IOP was 6.4% and for CCT was 0.4%. The 95% limits of agreement between examiners were -0.17 ± 1.42 mmHg (range: -2.95 to 2.61 mmHg) for IOP, -0.93 ± 4.37 μm (range: -9.50 to 7.64 μm) for CCT. The corrected IOP was significantly higher than the noncorrected IOP (P = 0.010.3). The noncorrected IOP significantly correlated with CCT (r = -0.4883, P = 0.0006). The corrected IOP showed no significant correlation with CCT (r = -0.0285, P = 0.8509). Conclusions. NT-530P offered repeatability and reproducibility in both IOP and CCT measurements. The corrected IOP calculated using the NT-530P was independent of the CCT, suggesting that this IOP may be less influenced by the central corneal thickness. [ABSTRACT FROM AUTHOR]

We analyzed the clonality and human papillomavirus (HPV) infection status of concurrent glandular and squamous lesions and adenosquamous carcinomas of the uterine cervix to clarify their histogenesis. The glandular and squamous components were clonally different from each other in 7 informative concurrent lesions. HPV was episomal in 2 polyclonal glandular dysplasias (GDs). HPV was in a mixed integrated-episomal form in a monoclonal GD, an adenocarcinoma in situ, and an adenocarcinoma. Both tumor components were monoclonal in origin in 6 adenosquamous carcinomas, with identical patterns of X-chromosomal inactivation and types and physical status of HPV. These results imply that the concurrent glandular and squamous lesions are formed separately, whereas adenosquamous carcinoma is more likely to be a combination tumor of monoclonal origin, and that integration of HPV has an important role in the progression from polyclonal GD through monoclonal expansion to adenocarcinoma in situ and adenocarcinoma. [ABSTRACT FROM AUTHOR]