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The aim of this study was to compare the postcapillary-sized venule (PCV) morphology of four young ALCA mice (35 days) and four colony-related aged mice (365 days) using the transmission electron microscope (TEM). Right and left mandibular first molar mesial roots with associated periodontal ligament (PDL) and bony socket, were used for TEM assessment. Five PCV profiles were selected at each 160µm interval, from the alveolar crest to the tooth apex. PCV profile dimensions were measured on standardised micrographs magnified x2900. Age affects were tested using multiple regression analysis. The number of PCV profiles in the tooth third of the PDL was higher in aged mice (p < 0.01) and comprised predominantly apericytic vessels (p < 0.001). The number of PCV profiles increased significantly (p < 0.001) in aged mice in the PDL middle circumferential third halfway down the molar root. Age had no significant affect on PCV diameter. Aged PDL permeability studies are needed to investigate whether the changes in aged PCV profile number are associated with functional modification of the PDL microvasculature.

Studies of the Mesolithic-Neolithic transition in Europe have focused on plants and animals exploited for food. However, the exploitation of plants for fibres underwent a significant change with the addition of domestic flax as a fibre crop. While the technology of flax fibre processing is increasingly understood by archaeologists, its material value as a fibre crop in comparison to indigenous fibre is less well explored. We examine the mechanical properties of flax and two indigenous fibres (lime bast, willow bast), by testing fibre strips for tensile properties and discuss the results in the light of material choices in these periods. [ABSTRACT FROM AUTHOR]

A series of pancake coils using several kilometers of second generation (2G) (RE)BCO conductor has been fabricated as a part of a R&D program to build a large aperture high field solenoid for energy storage application. This paper discusses the preparation of double pancake coils and the test results at 77 K before assembling the final magnet. These tests played an important role in assuring: the quality of conductors, coil winding and assembly, and integrity of splices within the coils. [ABSTRACT FROM PUBLISHER]

Background: Osteoprotegerin (OPG), as an osteoclast antagonist, limits mineralised tissue resorption under physiological conditions. Previous work investigating OPG in a rat periodontal ligament (PDL) ankylosis model found no inhibitory effect on osteoclasts when OPG was administered at a dosage of 2.5mg/kg. Aims: The object of this study was to determine whether dosages higher than 2.5 mg/kg of OPG were required to limit osteoclastic activity in an aseptic inflammatory model in rats. Materials and Methods: Dry ice was applied for 15 minutes to the upper right first molar crown of eighteen, 8-week-old, male Sprague-Dawley rats. Three groups of 3 were injected with OPG at dosages of 2.5, 5.0 and 7.5 mg/kg of body weight immediately following the thermal insult. After 7 days, the rats were sacrificed and each maxilla processed for histological examination and stained for osteoclastic activity using tartrate-resistant acid phosphatase (TRAP). Osteoclast population numbers were estimated via light microscopy and results were analysed using a comparative mixed model statistical analysis. Results: Results showed OPG inhibited osteoclastic activity in a dose-dependent manner. From 2.5 mg/kg to 7.5 mg/kg, osteoclast populations were linearly reduced by 39.78% (p < 0.05). OPG did not appear to affect the inflammatory process and had varied efficacy in different regions of individual teeth. Conclusion: Although osteoclastic activity reduced, it was not completely eliminated, perhaps because dosages were still inadequate, or additional factors might influence OPG and osteoclast activation in the aseptic inflammatory model. [ABSTRACT FROM AUTHOR]

Pancake coils are being fabricated using second generation (2G) High Temperature Superconductor (HTS) for a prototype 10 T solenoid. The length of conductor in each coil is 100 m and the inner diameter of the coil is 101 mm. The critical current of each coil was measured at 77 K in liquid nitrogen and down to \sim20 K in helium gas. It has been observed that the effect of thermal shock during cool-down may cause coil performance to degrade irreversibly. The detailed results and the improvements to achieve 10 T will be discussed. [ABSTRACT FROM AUTHOR]

Samples of YBCO superconductor from two manufacturers were irradiated with protons at the BLIP facility at BNL. Two specimens of each type of conductor were irradiated to five fluences covering the range from 1016 to 4 x 1017 protons/cm2. The beam parameters for the irradiations were 42 μA and 142 MeV. The critical current (zero field, 1 μV/cm) for all twenty samples was measured in liquid nitrogen before and after irradiation to quantify the effects of high-dose proton-induced radiation damage on the performance of the conductor, and thus evaluate its suitability for service in high-radiation environments. All of the specimens had a pre-irradiation current of about 100 A. This current decreased linearly with fluence, with a slope of about 20% per 1017 protons/cm2. The agreement between the two samples of each brand of conductor was exceptional. [ABSTRACT FROM AUTHOR]