The effect of a density difference on shear-layer instability

Measurements of mass flow rate and mean density have been made in separated laminar boundary layers with large transverse density gradients. Two-dimensional shear layers were formed by exhausting a half-jet of one gas into a reservoir of another gas with a different molecular weight. Two freons with a density ratio of 1-98 and unusual properties which permitted the measurement of the mass flow rate with a single hot wire were used. A n analysis of the mass flow rate fluctuations showed that a negative density gradient (i.e. light gas flowing into heavy) increases the amplification rate of the instability oscillations and reduces the frequency and wave number. Opposite trends were observed when the density gradient was positive. These findings are in agreement with recent theoretical predictions

Characterization of nucleoside transport in the intestinal protozoan parasite Giardia intestinalis.

A rapid sampling technique has been adapted and used to measure nucleoside transport in a human-derived isolate of the intestinal protozoan parasite Giardia intestinalis (syn. G. lamblia).Thesis (Ph.D.) -- University of Adelaide, Department of Microbiology and Immunology, 199

New Zealand Retirement Income: Policy as an ‘Eco-system’

The New Zealand retirement income system involves a range of policy areas and initiatives beyond New Zealand Superannuation and KiwiSaver. These interact with each other, and with wider social and economic trends. The potential for prolonging working lives, self-funding/decumulation and trends in homeownership need to be considered alongside the sustainability of current policy settings. A unified policy approach is required to ensure the adequacy of retirement incomes for older people and also intergenerational equity

Use of recombinant lentivirus pseudotyped with vesicular stomatitis virus glycoprotein G for efficient generation of human anti-cancer chimeric T cells by transduction of human peripheral blood lymphocytes in vitro

BACKGROUND: Genetic redirection of lymphocytes that have been genetically engineered to recognize antigens other than those originally programmed in their germlines is a potentially powerful tool for immunotherapy of cancers and potentially also of persistent viral infections. The basis for this procedure is that both cancers and some viruses have developed strikingly similar mechanisms of evading attacks by host immune mechanisms. To redirect human peripheral blood lymphocytes (PBLs) with a chimeric T cell receptor (chTCR) so that they recognize a new target requires a high degree of transfection efficiency, a process that is regarded as technically demanding. RESULTS: Infection with a retroviral vector carrying a chTCR cassette was shown to transduce 100% of rapidly dividing murine T cells but typically, only ~10% of PBLs could be infected with the same vector. In contrast with other retroviruses, lentiviruses integrate their genomes into non-dividing cells. To increase host cell range, vesicular stomatitis virus G protein was pseudotyped with a lentivirus vector, which resulted in ~100% PBL transduction efficiency. Signaling of PBLs bearing chimeric receptors was shown by specific proliferation on exposure to cells expressing cognate ligand. Further, T-bodies against CEA showed a startling abilty to cause regression of maligant colon tumors in a nude mouse model of human cancer. CONCLUSION: A lentivirus/VSV pseudotyped virus, which does not require replicating cells for integration of its genome, efficiently transduced a high proportion of human PBLs with chTCRs against CEA. PBLs transduced by infection with a lentivirus/VSV pseudotyped vector were able to proliferate specifically in vitro on exposure to CEA-expressing cells and further they had a startling therapeutic effect in a mouse model of human colon cancer

Influence of school community and fitness on prevalence of overweight in Australian school children

AbstractThe study objectives were (1) to determine the variation in prevalence of overweight between school communities, (2) to evaluate the relationship between cardiorespiratory fitness and the probability of being overweight among different school communities, and (3) to test whether this relationship varies between school communities. Using a repeated cross-sectional design, data from 31,424 (15,298 girls, 16,126 boys) Australian school children who had objective assessments of body composition and physical performance were used. Ninety-one schools located across 5 states and territories were included. Independent samples were taken across 12 school years (2000–2011). Analysis used generalised linear mixed models in R with a two-level hierarchical structure—children, nested within school communities. Predictor variables considered were: level 1—gender, age, cardiorespiratory fitness and year of measurement; level 2—school community. A total of 24.6% of the children were overweight and 69% were of low fitness. Variation in the prevalence of overweight between school communities was significant, ranging from 19% to 34%. The probability of being overweight was negatively associated with increasing cardiorespiratory fitness. The relationship was steepest at low fitness and varied markedly between school communities. Children of low fitness had probabilities of being overweight ranging between 26% and 75% depending on school community, whereas those of high fitness had probabilities of <2%. Our findings suggest that most might be gained from a public health perspective by focusing intervention on the least fit children in the worst-performing communities