The trial of Sir Francis Burdett, Bart. at Leicester, on Thursday, March 23d, 1820, before Mr. Justice Best, and a special jury ...

Mode of access: Internet.

Initial CFD investigation of an MR fluid in a bicycle ergometer

A bicycle ergometer is a scientific device used by exercise physiologists which attempts to mimic on-road cycling characteristics such as foot technique, EMG activity, VO2, VCO2 and rider cardiology in a laboratory environment. Presently there are no known useful scientific ergometers that mimic these characteristics and are able to provide a satisfactory controlled resistance that is independent of speed. Previous research has suggested the use of a Magneto-Rheological (MR) Fluid as part of the ergometer design, as when used in a rotary brake application it is able to be controlled electronically to increase resistance instantly and independent of speed. In the target application, MR fluids are subject to immense tribological wear and temperature during viscous shearing, and will eventually show some degree of deterioration which is usually manifested as an increase in off-state viscosity. It is not known exactly how the fluid fails, however the amount of deterioration is related to the shear rate, temperature and duration and directly related to the power dissipation. Currently, there is very little literature that investigates the flow and thermal characteristics of MR fluid tribology using CFD. In this paper, we present initial work that aims to improve understanding of MR fluid wear via CFD modelling using Fluent, and results from the model are compared with those obtained from a experimental test rig of an MR fluid-based bicycle ergometer.

Correlation of carotid atheromatous plaque inflammation with biomechanical stress: Utility of USPIO enhanced MR imaging and finite element analysis

Objective: The aim of this study was to explore whether there is a relationship between the degree of MR-defined inflammation using ultra small super-paramagnetic iron oxide (USPIO) particles, and biomechanical stress using finite element analysis (FEA) techniques, in carotid atheromatous plaques. Methods and Results: 18 patients with angiographically proven carotid stenoses underwent multi-sequence MR imaging before and 36 h after USPIO infusion. T2 * weighted images were manually segmented into quadrants and the signal change in each quadrant normalised to adjacent muscle was calculated after USPIO administration. Plaque geometry was obtained from the rest of the multi-sequence dataset and used within a FEA model to predict maximal stress concentration within each slice. Subsequently, a new statistical model was developed to explicitly investigate the form of the relationship between biomechanical stress and signal change. The Spearman's rank correlation coefficient for USPIO enhanced signal change and maximal biomechanical stress was -0.60 (p = 0.009). Conclusions: There is an association between biomechanical stress and USPIO enhanced MR-defined inflammation within carotid atheroma, both known risk factors for plaque vulnerability. This underlines the complex interaction between physiological processes and biomechanical mechanisms in the development of carotid atheroma. However, this is preliminary data that will need validation in a larger cohort of patients.

Recruitment sources of brown trout identified by otolith trace element signatures.

This study examined whether element: Ca ratios within the otoliths of juvenile brown trout could provide accurate trace element signatures for specific natal tributaries, and attempted to match these to trace element natal signatures found within the otoliths of adult trout caught in the main stem rivers of the same catchment. The trace element signatures of juvenile trout otoliths were analysed from a sample of eight tributaries representing the main sub-catchments of the Motueka River catchment, New Zealand. Trace element signatures were determined using laser ablation inductively coupled plasma mass spectrometry, and differentiated using linear discriminant function analysis with an overall cross-validated classification success of 96.8%. Temporal stability in element: Ca ratios was investigated by repeat collections of juvenile fish over two years. Natal signatures from 11 of 23 adult trout sampled from the catchment main stems were matched to one of the eight tributary signatures showing recruitment sources to be spread relatively evenly throughout the catchment. This study demonstrates the potential of using otolith trace element analysis to determine the natal origins of freshwater fish within a catchment.

Flocculation and removal of the brown tide organism, Aureococcus anophagefferens (Chrysophyceae), using clays

Previous attempts to remove the brown tide organism, Aureococcus anophagefferens, through flocculation with clays have been unsuccessful, in spite of adopting concentrations and dispersal protocols that yielded excellent cell removal efficiency (RE>90%) with other species, so a study was planned to improve cell removal. Four modifications in clay preparation and dispersal were explored: 1) varying the salinity of the clay suspension; 2) mixing of the clay-cell suspension after clay addition; 3) varying of concentration of the initial clay stock; 4) pulsed loading of the clay slurry. The effect of salinity was dependent on the clay mineral type: phosphatic clay (IMC-P2) had a higher RE than kaolinite (H-DP) when seawater was used to disperse the clay, but H-DP removed cells more efficiently when suspended in distilled water prior to application. Mixing after dispersal approximately doubled RE for both clays compared to when the slurry was layered over the culture surface. Lowering the concentration of clay stock and pulsing the clay loading increased RE, regardless of mineral type. However, this increase was more apparent for clays dispersed in seawater than in distilled water. In general, application procedures that decrease the rate of self-aggregation among the clay particles and increase the collision frequency between clay particles and A. anophagefferens achieve higher cell removal efficiency. These empirical studies demonstrated that clays might be an important control option for the brown tide organism, given the proper attention to preparation, dispersal methods, environmental impacts, and the hydrodynamic properties of the system being treated. Implications for the treatment of brown tides in the field are discussed.

SDSS J150722.30+523039.8: a cataclysmic variable formed directly from a detached white dwarf/brown dwarf binary?

We present high-speed, three-colour photometry of the eclipsing cataclysmic variable SDSS J150722.30+523039.8 (hereafter SDSS J1507). This system has an orbital period of 66.61 min, placing it below the observed `period minimum' for cataclysmic variables. We determine the system parameters via a parametrized model of the eclipse fitted to the observed lightcurve by ?2 minimization. We obtain a mass ratio of q = 0.0623 +/- 0.0007 and an orbital inclination . The primary mass is Mw = 0.90 +/- 0.01Msolar. The secondary mass and radius are found to be Mr = 0.056 +/- 0.001Msolar and Rr = 0.096 +/- 0.001Rsolar, respectively. We find a distance to the system of 160 +/- 10pc. The secondary star in SDSS J1507 has a mass substantially below the hydrogen burning limit, making it the second confirmed substellar donor in a cataclysmic variable. The very short orbital period of SDSS J1507 is readily explained if the secondary star is nuclearly evolved, or if SDSS J1507 formed directly from a detached white dwarf/brown dwarf binary. Given the lack of any visible contribution from the secondary star, the very low secondary mass and the low HeI ?6678/Ha emission-line ratio, we argue that SDSS J1507 probably formed directly from a detached white dwarf/brown dwarf binary. If confirmed, SDSS J1507 will be the first such system identified. The implications for binary star evolution, the brown dwarf desert and the common envelope phase are discussed.

Francis Pélissier [champion de France de cross cyclo-pédestre le 7 mars 1920] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 58363

Francis Pélissier [champion de France de cross cyclo-pédestre le 7 mars 1920] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 58364

Francis Pélissier [champion de France de cross cyclo-pédestre le 7 mars 1920] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 58365

Welland Canal Survey of Lands Nathan Pawling 1826; includes map and text.

Survey map and description of Nathan Pawling's land created by The Welland Canal Company. Included is a written description of the land along with a drawing of the land. Noteable features include; the dock, pier and tow path. The original bed of 12 mile creek is also noted on the map. Surveyor notes are seen in pencil on the map. The map notes the division of land between Pawling and Robert Brown's land. Click on 'detail' to see Map.