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ISO/CD 18857-2 (International Organization for Standardization, Geneva) describes a new international standard method for the determination of octylphenol, nonylphenol, their mono- and diethyoxylates, and bisphenol A in nonfiltered samples of drinking, ground, surface, and wastewater. The method is based on the extraction of the analytes from an acidified water sample by solid phase extraction, solvent elution, derivatization, and determination by gas chromatography with mass spectrometric detection. For validation of this method, 14 laboratories from 4 different countries in Europe and Canada participated in an interlaboratory trial to determine the performance characteristics of the method, which are intended for publication in the corresponding standard. The interlaboratory trial was evaluated according to ISO 5725-2 and included two duplicate nonfiltered water samples: surface water containing the target compounds in an analyte concentration range from 0.05 to 0.4 microg/L and wastewater containing the target compounds in a concentration ranged from 0.1 to 5 microg/L. The repeatability variation coefficients (within-laboratory precision) varied for all samples and compounds between 1.9 and 7.8%, showing a sufficiently high repeatability of the method. The reproducibility variation coefficients (between-laboratory precision) were found to vary within a satisfactory range of 10.0-29.5% for surface water and 10.8-22.5% for wastewater. The recoveries as a measure of accuracy varied from 98.0 to 144.1% for surface water and from 95.4 to 108.6% for wastewater. The determined concentrations of the samples compared well to the "true" values, thus showing very satisfactory accuracy of the method. In the chromatogram of the surface water sample, a high unresolved background made up of coextractable matrix compounds was apparent. It is conceivable that compounds from this background may be responsible for enhanced recoveries of 144.1% for 4-nonylphenol (mixture of isomers) and of 123.4% for 4-nonylphenol monoethoxylate (mixture of isomers) in the surface water samples. The isotope-marked standard compounds developed in this context proved to be reliable internal standards that allow a precise and accurate quantitation of all compounds specified in ISO/CD 18857-2. The results of the interlaboratory trial confirmed that the analytical method is robust and reliable and can be used as a standard method to analyze the target compounds in water samples.

OBJECTIVES - To determine the combined effects 1) of stress-field aspect ratio and velocity and compressive strain and 2) joint load, on temporomandibular joint (TMJ) disc mechanics. SETTING AND SAMPLE POPULATION - Fifty-two subjects (30 female; 22 male) participated in the TMJ load experiments. MATERIAL AND METHODS - In the absence of human tissue, pig TMJ discs were used to determine the effects of variables 1) on surface plowing forces, and to build a biphasic finite element model (bFEM) to test the effect of human joint loads and 2) on tissue stresses. In the laboratory, discs received a 7.6 N static load via an acrylic indenter before cyclic movement. Data were recorded and analysed using anova. To determine human joint loads, Research Diagnostic Criteria calibrated investigators classified subjects based on signs of disc displacement (DD) and pain (+DD/+pain, n = 18; +DD/-pain, n = 17; -DD/-pain, n = 17). Three-dimensional geometries were produced for each subject and used in a computer model to calculate joint loads. RESULTS - The combined effects of compressive strain, and aspect ratio and velocity of stress-field translation correlated with plowing forces (R(2) = 0.85). +DD/-pain subjects produced 60% higher joint loads (ANOVA, p < 0.05), which increased bFEM-calculated compressive strain and peak total normal stress. CONCLUSIONS - Static and dynamic variables of the stress-field and subject-dependent joint load significantly affect disc mechanics.

Changes in arterial wall composition and function underlie all forms of vascular disease. The fundamental structural and functional unit of the aortic wall is the medial lamellar unit (MLU). While the basic composition and organization of the MLU is known, three-dimensional (3D) microstructural details are tenuous, due (in part) to lack of three-dimensional data at micro- and nano-scales. We applied novel electron and confocal microscopy techniques to obtain 3D volumetric information of aortic medial microstructure at micro- and nano-scales with all constituents present. For the rat abdominal aorta, we show that medial elastin has three primary forms: with approximately 71% of total elastin as thick, continuous lamellar sheets, 27% as thin, protruding interlamellar elastin fibers (IEFs), and 2% as thick radial struts. Elastin pores are not simply holes in lamellar sheets, but are indented and gusseted openings in lamellae. Smooth muscle cells (SMCs) weave throughout the interlamellar elastin framework, with cytoplasmic extensions abutting IEFs, resulting in approximately 20 degrees radial tilt (relative to the lumen surface) of elliptical SMC nuclei. Collagen fibers are organized as large, parallel bundles tightly enveloping SMC nuclei. Quantification of the orientation of collagen bundles, SMC nuclei, and IEFs reveal that all three primary medial constituents have predominantly circumferential orientation, correlating with reported circumferentially dominant values of physiological stress, collagen fiber recruitment, and tissue stiffness. This high resolution three-dimensional view of the aortic media reveals MLU microstructure details that suggest a highly complex and integrated mural organization that correlates with aortic mechanical properties.

The results of treatment of carcinoma in situ of the uterine cervix in 380 patients seen between January 1, 1966 and December 31, 1973 are reported. There were 134 women age 40 or less. There were 246 patients age 40 or older. In 334 patients a total hysterectomy with removal of a vaginal cuff was carried out (87.9%). A large therapeutic cone biopsy was done in 46 patients (12.1%). In the 334 patients treated by hysterectomy, 2 recurrent carcinomas in situ of the vaginal vault were observed (0.6%). In 16 of the cases treated by conization later suspicious colposcopic and/or cytologic findings made hysterectomy necessary. In 5 of these cases a recurrent carcinoma in situ was likely. The postoperative morbidity after total hysterectomy was low. There was no postoperative death. The total vaginal hysterectomy with removal of a vaginal cuff is recommended as treatment for carcinoma in situ of the uterine cervix in order to avoid the diagnostic difficulties in the follow-up after treatment by conization and because of the low recurrence rate after hysterectomy. Conservative treatment should only be employed in patients who desire later child bearing. tthe psychological stresses of the continually required follow-up examinations after conization should not be underestimated.