De-Intensification of Grasslands: Understanding the Processes to Find the Balance

There is a growing trend in Australia and other developed countries for deintensification of animal production from grasslands and for grasslands to be used for purposes other than livestock grazing. These shifts are occurring for a variety of reasons including unsustainable land management practices, environmental pollution, loss of conservation value, poor commodity prices and declining rural infra-structure and communities. In Australia, the shifts are under way in agricultural grasslands, where sown pastures occur in a matrix of semi-natural woodlands, but less so in the other three major natural grasslands that forms the arid and semi-arid rangelands. The conversion of natural wooded grasslands to agricultural grasslands, often involving crop/pasture rotations, began over 100 years ago in those regions of Australia where rainfall was sufficiently high and regular to allow cropping and pasture sowing. Later, agricultural research identified soil nutrient deficiencies, found European and African grasses and legumes to utilise the raised fertility and developed machines that raised the scale and efficiency of livestock production. Governments promoted pasture improvement, and with livestock breeding, fibre and meat production per hectare was significantly raised. The Australian people in general, accepted as worthwhile and successful the conversion to agricultural grasslands. Conquering the “bush”, taming nature and establishing livestock grazing businesses were seen to be appropriate activities for rural pioneers and later generations. However, doubts about the long-term sustainability of livestock grazing businesses on agricultural grasslands and to a lesser extent other natural grasslands, have grown in the minds of scientists and pastoralists and now the public. Salt has risen to the surface in many regions from tree removal changing hydrological processes. Soils have poor structure and low potential productivity. Added nutrients and chemicals are moving off property with undesirable and public consequences eg toxic algal blooms in rivers. Significant species extinction within Australia’s unique plants and animals are linked to land clearing and pastoral management; survival of many threatened species is problematic. Persistent low commodity prices for traditional products are making many livestock grazing businesses untenable. Rural communities are struggling to survive with the withdrawal of services by Government and major businesses. These problems are being addressed across many fronts. Foremost there is a substantial and growing ownership of the problems by rural communities through “Landcare” and catchment management groups. Research into the sustainability of low-input native pasture systems, the spatial requirements for remnant and plantation vegetation (amount, location and continuity) to lower water tables, ecosystem services and processes involving native plants and animals, effective mechanisms for knowledge sharing and alternative land uses are underway

Mortality Model for a Perennial Grass in Australian Semi-Arid Wooded Grasslands Grazed by Sheep

Grazing of sheep in marginal semi-arid environments is risky because grazing appears to predispose grass plants, especially palatable species, to sudden death (Hodgkinson, 1994; 1995). These early observations were based on a preliminary analysis of perennial grass survival in a single drought and supported the concept of tactical grazing proposed by Westoby et al. (1989) as a preferred management. Later this idea was developed by suggesting the existence of critical thresholds for perennial grass survival, which when crossed, collapses grass populations (Hodgkinson, 1994). Here we examine the relationship between mortality of a palatable perennial grass, Thyridolepis mitchelliana, and a number of variables measured during a 10-year period

Modelling Basal Area of Perennial Grasses in Australian Semi-Arid Wooded Grasslands

In many semi-arid pastoral systems, landscape processes easily become dysfunctional. Shifts to less functional states may be irreversible, and have long-term consequences for pastoral profitability and social viability of rural communities. Typically, shifts to lower functional states involve a decline in perennial grasses (Hodgkinson, 1994). Here we develop a conceptual basis for modelling the basal area of perennial grasses in a semi-arid grassland and validate the model using data from a 10-year grazing study

Sheep Grazing During Drought Collapses the Perennial Grass Resource in Australian Semiarid Wooded Grasslands

Grazing of sheep in arid grasslands is risky; sudden shifts to lower functional states may occur when the ecosystem is stressed (Scheffer et al., 2001). To avoid the stresses that shift states, easy-to-recognise critical thresholds need to be identified (Westoby et al., 1989). Preliminary analysis of perennial grass survival in a drought indicated a critical threshold based on co-occurrence of drought and grazing. Crossing this threshold collapses grass populations (Hodgkinson, 1994). Here we examine the relationships between basal area change and rainfall and grazing levels based on a 10-year period and propose a management guideline

A caspase-3 'death-switch' in colorectal cancer cells for induced and synchronous tumor apoptosis in vitro and in vivo facilitates the development of minimally invasive cell death biomarkers

Novel anticancer drugs targeting key apoptosis regulators have been developed and are undergoing clinical trials. Pharmacodynamic biomarkers to define the optimum dose of drug that provokes tumor apoptosis are in demand; acquisition of longitudinal tumor biopsies is a significant challenge and minimally invasive biomarkers are required. Considering this, we have developed and validated a preclinical 'death-switch' model for the discovery of secreted biomarkers of tumour apoptosis using in vitro proteomics and in vivo evaluation of the novel imaging probe [ 18 F]ML-10 for non-invasive detection of apoptosis using positron emission tomography (PET). The 'death-switch' is a constitutively active mutant caspase-3 that is robustly induced by doxycycline to drive synchronous apoptosis in human colorectal cancer cells in vitro or grown as tumor xenografts. Deathswitch induction caused caspase-dependent apoptosis between 3 and 24 hours in vitro and regression of 'death-switched' xenografts occurred within 24 h correlating with the percentage of apoptotic cells in tumor and levels of an established cell death biomarker (cleaved cytokeratin-18) in the blood. We sought to define secreted biomarkers of tumor apoptosis from cultured cells using Discovery Isobaric Tag proteomics, which may provide candidates to validate in blood. Early after caspase-3 activation, levels of normally secreted proteins were decreased (e.g. Gelsolin and Midkine) and proteins including CD44 and High Mobility Group protein B1 (HMGB1) that were released into cell culture media in vitro were also identified in the bloodstream of mice bearing death-switched tumors. We also exemplify the utility of the death-switch model for the validation of apoptotic imaging probes using [ 18 F]ML-10, a PET tracer currently in clinical trials. Results showed increased tracer uptake of [ 18 F]ML-10 in tumours undergoing apoptosis, compared with matched tumour controls imaged in the same animal. Overall, the death-switch model represents a robust and versatile tool for the discovery and validation of apoptosis biomarkers. © 2013 Macmillan Publishers Limited. All rights reserved

British research in accounting and finance (2001–2007): the 2008 research assessment exercise

No abstract available

Perspective: Current advances in solid-state NMR spectroscopy

In contrast to the rapid and revolutionary impact of solution-state Nuclear Magnetic Resonance (NMR) on modern chemistry, the field of solid-state NMR has matured more slowly. This reflects the major technical challenges of much reduced spectral resolution and sensitivity in solid-state as compared to solution-state spectra, as well as the relative complexity of the solid state. In this perspective, we outline the technique developments that have pushed resolution to intrinsic limits and the approaches, including ongoing major developments in the field of Dynamic Nuclear Polarisation, that have enhanced spectral sensitivity. The information on local structure and dynamics that can be obtained using these gains in sensitivity and resolution is illustrated with a diverse range of examples from large biomolecules to energy materials and pharmaceuticals and from both ordered and highly disordered materials. We discuss how parallel developments in quantum chemical calculation, particularly density functional theory, have enabled experimental data to be translated directly into information on local structure and dynamics, giving rise to the developing field of “NMR crystallography

Dispelling the myths of online education: learning via the information superhighway

There continues to be a perception that online education is inferior to traditional education. In the U.S. online learning is more developed than in the U.K. This paper provides insights into a U.S. provision and takes a close look at what are perceived as weaknesses of on line learning and argues that these are not necessarily inherent weaknesses of this form of educational delivery. Then, results of two major studies, undertaken in the U.S. are provided comparing the effectiveness of online education to traditional education as perceived by current MBA students and past graduates. Results of these studies suggest that students of MBA modules and MBA graduates perceive the quality and effectiveness of online education to be similar to, if not higher than, the quality and effectiveness of traditional modules and programmes

Is self monitoring of blood pressure in pregnancy safe and effective?

Guidelines encourage the use of self-monitoring of blood pressure in pregnancy, and research suggests that women prefer it. But the blood pressure monitoring in pregnancy group (BUMP) explain that our enthusiasm may run ahead of the evidence. They outline what is known and call for better understanding before self-monitoring is implemented