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Author(s): Pietro Piffanelli [1, 7, 8]; Luke Ramsay [2, 7]; Robbie Waugh [2]; Abdellah Benabdelmouna [3]; Angélique D'Hont [3]; Karin Hollricher [4]; Jørgen Helms Jørgensen [5]; Paul Schulze-Lefert (corresponding author) [...]

Polystyrene-based nanocomposites (PNC) were prepared using three grades of polystyrene (different molecular weights). The resin was melt-compounded with 0 to 10 wt% of commercial organoclay in a co-rotating twin-screw extruder. Owing to thermooxidative degradation the degree of dispersion was poor. The rheological properties of PNC were determined under dynamic and steady state shear as well as under extensional flow conditions. At the higher clay content, dynamic strain sweep demonstrated that the storage and loss moduli decrease continuously with an increase of strain. To characterize this nonlinear viscoelastic behavior, the Fourier-transform rheology was applied. The low strain frequency sweep showed that the storage and loss moduli increase with organoclay content. The extracted zero-shear viscosity data were used to calculate the intrinsic viscosity and then the aspect ratio of dispersions. In spite of nonlinear viscoelastic behavior, the time-temperature superposition was observed in the full range of concentration. The horizontal and vertical shift factors were found to be almost independent of organoclay content and molecular weight of PS. For comparison, PNC was also prepared by the solution method. A high degree of dispersion was obtained, reflected in the aspect ratio: p = 269, to be compared with p = 16 calculated for the melt-compounded PNC. Polym. Eng. Sci. 44:1061-1076, 2004., INTRODUCTION General The rheological properties of polymer nanocomposites (PNC) are pertinent to processing. The first use of an organoclay in polymers was to reinforce elastomers (1). The authors combined montmorillonite [...]

The study of distribution, localization, and smooth muscle effects of pituitary adenylate cyclase activating polypeptide (PACAP) in the human female genital tract reveals that the highest concentrations of PACAP-38 is found in ovary, vaginal upper parts, and perineum. The concentration level of PACAP-27 are normally very low, but its presence causes a concentration-dependent relaxation of spontaneous activity in the non-vascular fallopian muscle strips. Thus the findings suggest that PACAP plays a smooth muscle regulatory role in the human female reproductive tract.

Obese women treated with growth hormone (GH) showed reduced total fat mass and increased lean body mass and turned resistant to insulin at the time of (GH) treatment, exhibiting high levels of glucose and insulin in plasma. Adipose tissue reduction resulting from treatment with GH was identical in all regions of measurement and lipoprotein lipase activity came down as a result of GH treatment.

A Danish anthropological collection of medieval human skeltons excavated in 1986 involves a mandible (No. 212) from an adult female born without the lower alveolar nerve and mandibular canal. It is believed that the defect has resulted in lack of tooth development on the affected side and that the mylohyoid nerve has partially compensated for this defect by development of teeth in localized areas. The defective mandibular dentition has caused a compensatory development of the alveolar process in the maxilla. The missing occlusal support has altered muscular traction on the mandible. This has caused an alteration in mandibular shape. Whether the asymmetric development of the mandible is caused by muscular dysfunction, by failure in angular growth apposition, or by a combination of these factors is discussed. The case presents valuable data in the ongoing discussion about the interaction between nerve tissue and tooth formation and about the interaction between occlusion, jaw morphology, and muscular traction. The study shows how archeological material in an interdisciplinary cooperation between archeological, embryological and orthodontic research can contribute to the clarification of current biological problems.

Over a period both a monetary and physical measure of antihypertensive drug consumption has increased in Denmark, but the consumption has varied considerably between counties in any given year. Concurrently. SMR for myocardial infarctions and cerebrovascular diseases due to hypertension has declined. The relation between intensity of treatment and outcome in terms of reduced loss of life time or healthy time is analyzed at an aggregate level within a health economic framework. The relation is analyzed by using a pooled time series cross section regression analysis. Two models, a covariance and an error component model are used. Within the range of observed drug consumption, loss of life years and loss of good health show a tendency towards negative regression on consumption of drugs when controlled for relevant variables such as occupational structure, degree of urbanization, and hardness of the drinking water. Key words--regional variation, hypertension, antihypertensive, regression