Australian National University

About: Australian National University is a education organization based out in Canberra, Australian Capital Territory, Australia. It is known for research contribution in the topics: Population & Galaxy. The organization has 34419 authors who have published 109261 publications receiving 4315448 citations. The organization is also known as: The Australian National University & ANU.

IFN-gamma plays a critical down-regulatory role in the induction and effector phase of myelin oligodendrocyte glycoprotein-induced autoimmune encephalomyelitis.

Abstract: 129/Sv mice are resistant to induction of experimental autoimmune encephalomyelitis (EAE) induced with myelin oligodendrocyte glycoprotein peptide (MOG35-55). Mice of this strain lacking the gene coding for the ligand-binding chain of the IFN-gamma receptor develop EAE with high morbidity and mortality. Spleen cells from sensitized IFN-gammaR-/- mice proliferated extensively when stimulated with MOG peptide in culture and produced high levels of IFN-gamma and TNF but no detectable IL-4. Transfer of spleen cells from sensitized IFN-gammaR-/- mice produced EAE in both IFN-gammaR+/+ and IFN-gammaR-/- recipients. Disease was severe in IFN-gammaR-/- recipients and mortality high (77%). Surviving mice remained moribund until termination of the experiments. IFN-gammaR+/+ recipients developed disease of equal severity, but with no mortality, and recovered significantly. These results indicate that IFN-gamma is not essential for the generation or function of anti-MOG35-55 effector cells but does play an important role in down-regulating EAE at both the effector and induction phase of disease.

Biological invasions in the Antarctic: extent, impacts and implications.

Abstract: Alien microbes, fungi, plants and animals occur on most of the sub-Antarctic islands and some parts of the Antarctic continent. These have arrived over approximately the last two centuries, coincident with human activity in the region. Introduction routes have varied, but are largely associated with movement of people and cargo in connection with industrial, national scientific program and tourist operations. The large majority of aliens are European in origin. They have both direct and indirect impacts on the functioning of species-poor Antarctic ecosystems, in particular including substantial loss of local biodiversity and changes to ecosystem processes. With rapid climate change occurring in some parts of Antarctica, elevated numbers of introductions and enhanced success of colonization by aliens are likely, with consequent increases in impacts on ecosystems. Mitigation measures that will substantially reduce the risk of introductions to Antarctica and the sub-Antarctic must focus on reducing propagule loads on humans, and their food, cargo, and transport vessels.

Elevated atmospheric partial pressure of CO2 and plant growth

Abstract: Cotton and maize plants were grown under full sunlight in glass houses containing normal ambient partial pressure of CO2 (330±20 μbar) and enriched partial pressure of CO2 (640 ±15 μbar) with four levels of nitrogen nutrient. In 40 day old cotton plants grown in high CO2, there was a 2-fold increase in day weight and a 1.6-fold increase in leaf area compared with plants grown in ambient CO2. In 30 day old maize plants there was only 20% increase in dry weight in plants grown in 640 μbar CO2 compared with plants grown in 330 μbar and no significant increase in leaf area. In both species, at both CO2 treatments, dry weight and leaf area decreased in similar proportion with decreased nitrogen nutrient. The increase of leaf area in cotton plants at high CO2 caused a reduction of total nitrogen on a dry weight basis. In cotton assimilation rate increased 1.5 fold when plants were grown with high nitrogen and high CO2. The increase was less at lower levels of nitrate nutrient. There was a 1.2 fold increase in assimilation rate in maize grown at high CO2 with high nitrate nutrient. Cotton and maize grown in high CO2 had a lower assimilation rate in ambient CO2 compared to plants grown in normal ambient air. This difference was due to the reduction in RuBP carboxylase activity. Water use efficiency was doubled in both cotton and maize plants grown at high CO2 in all nutrient treatments. However, this increase in water use efficiency was due primarily to reduced transpiration in some treatments and to increased assimilation in others. These data show that plant responses to elevated atmospheric partial pressure of CO2 depend on complex of partially compensatory processes which are not readily predictable.

The diversity and coevolution of rubisco, plastids, pyrenoids, and chloroplast-based co2-concentrating mechanisms in algae

Abstract: Algae have adopted two primary strategies to maximize the performance of Rubisco in photosynthetic CO2 fixation. This has included either the development of a CO2-concentrating mechanism (CCM), bas...