Visualization of Cytoskeletal Elements and Associated Retroviral Antigens by Immunogold Transmission Electron Microscopy of Detergent Extracted Cells

Several investigators have reported an association between the cytoskeleton and viral antigens. In our laboratory, biochemical immunofluorescence and immuno-gold electron microscopy studies were conducted on TX-100 extracted NIH/3T3 cells infected with Moloney-murine leukemia virus. Cytochalasin B treatment causes reversible microfilament disruption and a concomitant decrease in virus production. No effect on microtubules was seen. Immuno-gold electron microscopy reveals an association between cytoskeletal action and the viral antigens gp70 and p15E. The results of these immunocytological and biochemical studies indicate that the cytoskeleton may play an integral role in transport and processing of viral gene-envelope products

Perpendicular-to-grain compression behaviour of screw reinforced timber and a novel application of digital image correlation

This project investigates various factors which influence the behaviour of a timber roof structure designed by Smith & Wallwork Engineers. The first part of the project focused on material of sweet chestnut, where Digital Image Correlation (DIC) was employed to obtain values for the shear modulus. DIC was able to implement the shear field test method prescribed in BS EN 408:2010, along with two new methods developed based on additional information available through DIC. These methods were accurate, fast to implement, and potentially more robust than the shear field test method. A method to estimate the true value of the Timoshenko shear coefficient was also developed. The second section of the project involved physical testing of portions of the roof structure to investigate the behaviour of screw-reinforced and unreinforced timber loaded perpendicular to grain. Together with finite element modelling, it was noticed that a key aspect of the connection's behaviour was the axial force transfer between overlapping screws via shear in the timber, and the resulting relative displacement between the screws. A simple spring model was developed to characterise the compression stiffness of the roof which can now be used in reverse to calculate the forces due to moisture expansion or contraction

Recent Developments: The Uniform Arbitration Act

Since 1983, this annual Article 2 has been prepared to provide a survey of recent developments in the case law interpreting and applying the various state versions of the Uniform Arbitration Act3. The purpose is to promote uniformity in the interpretation of the U.A.A. by developing and explaining the underlying principles and rationales courts have applied in recent cases.

Development and geometry of isotropic and directional shrinkage crack patterns

We have studied shrinkage crack patterns which form when a thin layer of an alumina/water slurry dries. Both isotropic and directional drying were studied. The dynamics of the pattern formation process and the geometric properties of the isotropic crack patterns are similar to what is expected from recent models, assuming weak disorder. There is some evidence for a gradual increase in disorder as the drying layer become thinner, but no sudden transition, in contrast to what has been seen in previous experiments. The morphology of the crack patterns is influenced by drying gradients and front propagation effects, with sharp gradients having a strong orienting and ordering effect.Comment: 8 pages, 11 figures, 8 in jpg format, 3 in postscript. See also http://mobydick.physics.utoronto.ca/mud.htm

Working group written presentation: Trapped radiation effects

The results of the Trapped Radiation Effects Panel for the Space Environmental Effects on Materials Workshop are presented. The needs of the space community for new data regarding effects of the space environment on materials, including electronics are listed. A series of questions asked of each of the panels at the workshop are addressed. Areas of research which should be pursued to satisfy the requirements for better knowledge of the environment and better understanding of the effects of the energetic charged particle environment on new materials and advanced electronics technology are suggested

Influence of random roughness on the Casimir force at small separations

The influence of random surface roughness of Au films on the Casimir force is explored with atomic force microscopy in the plate-sphere geometry. The experimental results are compared to theoretical predictions for separations ranging between 20 and 200 nm. The optical response and roughness of the Au films were measured and used as input in theoretical predictions. It is found that at separations below 100 nm, the roughness effect is manifested through a strong deviation from the normal scaling of the force with separation distance. Moreover, deviations from theoretical predictions based on perturbation theory can be larger than 100%.Comment: 18, 5 figure

Child Psychosocial Adjustment and Parenting in Families Affected by Maternal HIV/AIDS

Child adjustment and parenting were examined in 23 9-through 16-year-old youth from families affected by maternal HIV infection and 20 same-age peers whose mothers were not infected. Children whose mothers were seropositive reported significantly more externalizing problems. Infected mothers reported less age-appropriate supervision/monitoring relative to non-infected mothers. Better mother-child relationship quality and less impairment in parental supervision/monitoring of age-appropriate youth behaviors were associated with fewer externalizing difficulties among the HIV-positive group only. Similarly, only among HIV-infected mothers was refraining from engaging in inconsistent disciplinary tactics associated with lower reports of internalizing and externalizing problems. These data highlight the promise of programs targeting parenting skills to prevent or ameliorate child difficulties

Light your runways and taxiways without electricity

The history of the radioluminescent light program at Oak Ridge National Laboratory is from the earliest use of radium through strontium-90, carbon-14, and krypton-85 to the present work with tritium. Field testing of radioluminescent lights and safety and quality control are discussed. (MHR