Transport, storage and mobilization of nitrogen by trees and shrubs in the wet/dry tropics of northern Australia

Xylem sap from woody species in the wet/dry tropics of northern Australia was analyzed for N compounds. At the peak of the dry season, arginine was the main N compound in sap of most species of woodlands and deciduous monsoon forest. In the wet season, a marked change occurred with amides becoming the main sap N constituents of most species. Species from an evergreen monsoon forest, with a permanent water source, transported amides in the dry season. In the dry season, nitrate accounted for 7 and 12% of total xylem sap N in species of deciduous and evergreen monsoon forests, respectively In the wet season, the proportion of N present as nitrate increased to 22% in deciduous monsoon forest species. These results suggest that N is taken up and assimilated mainly in the wet season and that this newly assimilated N is mostly transported as amide-N (woodland species, monsoon forest species) and nitrate (monsoon forest species). Arginine is the form in which stored N is remobilized and transported by woodland and deciduous monsoon forest species in the dry season. Several proteins, which may represent bark storage proteins, were detected in inner bark tissue from a range of trees in the dry season, indicating that, although N uptake appears to be limited in the dry season, the many tree and shrub species that produce flowers, fruit or leaves in the dry season use stored N to support growth. Nitrogen characteristics of the studied species are discussed in relation to the tropical environment.

Exploratory research: Citizen participation, local government and sustainable development in Australia

Exploratory research reported in this paper was undertaken in Adelaide, Australia during 1998/99. The purpose of the research is to explore local development practice as evidenced through the experiences and actions of local citizens, community based groups and local government (Neuman, 1994). Results from this first stage research suggest that sustainability initiatives in Australia might best be implemented through a collaborative approach at the local community level involving local citizens working in partnership with local government. Copyright (C) 2002 John Wiley & Sons, Ltd and ERP Environment.

The initial effects of a Mulligan's mobilization with movement technique on dorsiflexion and pain in subacute ankle sprains

Physiotherapists frequently use manipulative therapy techniques to treat dysfunction and pain resulting from ankle sprain. This study investigated whether a Mulligan's mobilization with movement (MWM) technique improves talocrural dorsiflexion, a major impairment following ankle sprain, and relieves pain in subacute populations. Fourteen subjects with subacute grade II lateral ankle sprains served as their own control in a repeated measures, double-blind randomized controlled trial that measured the initial effects of the MWM treatment on weight bearing dorsiflexion and pressure and thermal pain threshold. The subacute ankle sprain group studied displayed deficits in dorsiflexion and local pressure pain threshold in the symptomatic ankle. Significant improvements in dorsiflexion occurred initially post-MWM (F-(2,F-26) 7.82, P = 0.002), but no significant changes in pressure or thermal pain threshold were observed after the treatment condition. Results indicate that the MWM treatment for ankle dorsiflexion has a mechanical rather than hypoalgesic effect in subacute ankle sprains. The mechanism by which this occurs requires investigation if we are to better understand the role of manipulative therapy in ankle sprain management. (C) 2003 Elsevier Ltd. All rights reserved.

Storage protein mobilization and thiol protease up-regulation by solid matrix priming in loblolly pine (Pinus taeda) seed embryos

Experiments were conducted to investigate physiological mechanisms of solid matrix priming (SMP) on germination enhancement of loblolly pine (Pinus taeda) seeds. During SMP, osmotic potential in the embryo decreased by 0.65 MPa, concentration of crystalloid proteins decreased to 62% and concentrations of buffer soluble proteins and free amino acids increased by 22% and by 166%, respectively. Observations under an electron microscope demonstrated protein bodies in the embryo were mobilized. Inhibitor analysis indicated thiol protease was the dominant enzyme among endopiptidases to degrade the reserved proteins. A fragment of thiol protease was cloned from the primed seed embryos and it has high identities to those thiol proteases responsive to water stress. RNA get blot analysis showed a 1.5 kb thiol protease gene was up-regulated by SMP. Treatment with E64, a thiol protease inhibitor, negated SMP effects on germination performance, water potentials and protein profiles. Based on the experimental results, reserve protein mobilization induced by SMP in the embryo before radicle emergence might be one of the mechanisms to enhance germination in loblolly pine seeds.

History and habit in the mobilization of ICT resources

Evidence demonstrates that the digital divide is deepening despite strategies mobilized worldwide to reduce it. In disadvantaged communities, beyond training and infrastructural issues, there often lies a range of cultural and historically formed relationships that affect people's adoption of ICTs. This article presents an analysis of local resident's engagement with their council's pilot project to develop a computer facility in their community center. We ask, to what extent can people in poor urban communities, once trained, be expected to volunteer to work on furthering community education and development in ICTs in their local area? Findings indicate four patterns of individual engagement with the computer project: reflexive, utilitarian, distributive, and nonparticipatory. It is argued that local people engaged with the intervention in historically patterned and locally distinctive ways that served immediate personal and pragmatic ends. They did not adopt the long-term strategic goals of the council or university.