Tritangent centres,Pascal's theorem and Thebault's problem

Thébault's problem was posed in 1938, but a solution did not appear until 1983. Since then other solutions of the original problem and of various generalisations have been given. In this paper we discuss the generalisations (including some new results) and various background theorems on tritangent centres, making extensive use of Pascal's theorem.     

Equation of state of simple dense fluids. Thermal pressure coefficients and effective hard sphere diameters

The thermal pressure coefficient of a fluid may be simply related to the hard sphere term in a van der Waals type of equation of state. Experimental data for liquid argon and simulation results for a Lennard-Jones 12-6 fluid have been used to give information about the temperature dependence of the hard sphere diameter. The implications of this behaviour have been briefly discussed.     

Interaction second virial coefficients at low temperatures for NeKr and NeO2 systems

Published results of vapour—liquid and vapour—solid equilibrium studies for neon—krypton and neon—oxygen mixtures have been analysed to give values for the interaction second virial coefficients. B₁₂. Comparisons are made with other results for the NeKr system and with the predictions of some proposed intermolecular potentials.     

A Hierarchical Structural Model for the Interpretation of Mercury Porosimetry and Nitrogen Sorption

A new model of interpretation for the mercury porosimetry experiment has been presented. The void space of a porous solid is modeled by separate representations of both the macroscopic (>10 μm) and the mesoscopic (<10 μm) length scale properties of the material. Complementary information from nitrogen adsorption, on the mesoscopic scale, and NMR imaging, on the macroscopic scale, is used in conjunction with the mercury porosimetry data to provide a more accurate structural representation of a porous medium. The model is therefore able to probe spatial geometric changes in pellet structural architecture over many length scales during processes such as catalyst manufacture and the deactivation of catalysts by coke deposition. Copyright 2000 Academic Press.     

4 + 1] cycloaddition of bis(alkylthio)carbenes with vinyl isocyanates. Total synthesis of (+/-)-mesembrine

[reaction: see text] The Sceletium alkaloid mesembrine has been synthesized in 13% overall yield by a sequence featuring a [4 + 1] cycloaddition of a bis(alkylthio)carbene with a functionalized vinyl isocyanate.     

Effect of Nozzle Exit Turbulence on the Column Trajectory and Breakup Location of a Transverse Liquid Jet in a Gaseous Flow

This study examines the effect of fully developed turbulent flow at the exit of nozzle/injector on the trajectory and column breakup location of a liquid jet injected transverly into a gaseous crossflow. Liquid jet trajectory and column breakup for different nozzle geometries at different velocities of liquid jet and crossflow are analytically and experimentally Investigated. Shadowgraph imaging technique is used to determine the jet trajectory and breakup location of a transverse liquid jet in a uniform airflow. Particle image velocimetry (PIV) is used to measure the near-field velocity profile of a liquid jet discgarged into a quiescent atmosphere. The experimental results show a higher penetration and breakup height for the liquid jet ensuing from a nozzle with a smaller length to diameter ratio. This is due to the surface irregularities of the liquid column of a turbulent jet, which breaks up and consequently follows the cross airflow sooner. In order to capture the effect of turbulence, the analytical trajectory correlation developed in our previous studies is modified to account for the discharge coefficient of a nozzle. The discharge coefficient is estimated indirectly by comparing the liquid column trajectory predicted by the modified analytical correlation with that determined experimentally. The indirectly determined discharge coefficient is then used in the analytical correlation for predicting the breakup height of a transverse liquid jet. The results predicted using this approach are in good agreement with the experimental data of the present study at standard temperature and pressure (STP) test conditions.     

Complementary Approaches to Imaging Subcellular Lipid Architectures in Live Bacteria Using Phosphorescent Iridium Complexes and Raman Spectroscopy

A family of three neutral iridium(III) tetrazolato complexes are investigated as bacterial imaging agents. The complexes offer a facile tuning of the emission colour from green (520 nm) to red (600 nm) in aqueous media, while keeping the excitation wavelength unchanged. The three complexes do not inhibit the bacterial growth of Bacillus Cereus, used as a model in this study, and exhibit extremely fast cellular uptake. After a minute incubation time, the nontoxic complexes show subcellular localisation in spherical structures identified as lipid vacuoles. Confocal Raman imaging has been exploited for the first time on live bacteria, to provide direct and label-free mapping of the lipid-enriched organelles within B. cereus, complementing the use of luminescent probes. Examination of the Raman spectra not only confirmed the presence of lipophilic inclusions in B. cereus but offered additional information about their chemical composition, suggesting that the lipid vacuoles may contain polyhydroxybutyrate (PHB).     

Experimental Measurement of Specific Impulse Distribution and Transient Deformation of Plates Subjected to Near-Field Explosive Blasts

Experimental Mechanics - The shock wave generated from a high explosive detonation can cause significant damage to any objects that it encounters, particularly those objects located close to the...     

Silibinin Treatment Inhibits the Growth of Hedgehog Inhibitor‐Resistant Basal Cell Carcinoma Cells via Targeting EGFR‐MAPK‐Akt and Hedgehog Signaling

Basal cell carcinoma (BCC) is the most common skin malignancy. Deregulated hedgehog signaling plays a central role in BCC development; therefore, hedgehog inhibitors have been approved to treat locally advanced or metastatic BCC. However, the development of resistance to hedgehog inhibitors is the major challenge in effective treatment of this disease. Herein, we evaluated the efficacy of a natural agent silibinin to overcome resistance with hedgehog inhibitors (Sant‐1 and GDC‐0449) in BCC cells. Silibinin (25–100 μm ) treatment for 48 h strongly inhibited growth and induced death in ASZ001, Sant‐1‐resistant (ASZ001‐Sant‐1) and GDC‐0449‐resistant (ASZ001‐GDC‐0449) BCC cells. Furthermore, colony‐forming ability of ASZ001, ASZ001‐Sant‐1 and ASZ001‐GDC‐0449 cells was completely inhibited by silibinin treatment. Molecular analysis showed that silibinin treatment decreased the level of phosphorylated EGFR (Tyrosine 1173) and total EGFR in ASZ001‐Sant‐1 cells, key signaling molecules responsible for BCC resistance toward hedgehog inhibitors. Further, silibinin treatment decreased the phosphorylated Akt (Serine 473), phosphorylated ERK1/2 (Threonine 202/Tyrosine 204), cyclin D1 and Gli‐1 level but increased the SUFU expression in ASZ001‐Sant‐1‐resistant cells. Silibinin treatment of ASZ001‐Sant‐1‐resistant cells also decreased bcl‐2 but increased cleaved caspase 3 and PARP cleavage, suggesting induction of apoptosis. Together, these results support silibinin use to target hedgehog inhibitor‐resistant BCC cells.