A financial analysis of the effect of the mix of crop and sheep enterprises on the risk profile of dryland farms in south-eastern Australia

This study analyses the financial risk faced by representative mixed-enterprise farm businesses in four regions of south-eastern Australia. It uses discrete stochastic programming to optimise the ten-year cash flow margins produced by these farms operating three different farming systems. Monte Carlo analysis is used to produce a risk profile for each scenario, derived from multiple runs of this optimised model, randomised for commodity prices and decadal growing season rainfall since 1920. This analysis shows that the performance of the enterprise mixes at each site is characterised more by the level of variability of possible outcomes than by the mean values of financial outputs. It demonstrates that relying on mean values for climate and prices disguises the considerable risks involved with cropping in this area. Diversification into a Merino sheep enterprise marginally reduced the probability of financial loss at all sites. This study emphasises the fact that the variability, or risk, associated with all scenarios far exceeds the likely change in cash margins due to innovation and good management. It further shows that farm managers should give a higher priority to adopting innovations which reduce costs, rather than increase productivity, in order to reduce risk. Further analysis shows that the current static measures of financial performance (gross margins, profit and cash margins) do not characterise the risk-adjusted performance of the various farming systems and almost certainly result in a flawed specification of best-practice farm management in south-eastern Australia.Farm Management,

Creating Church Online: An Ethnographic Study of Five Internet-Based Christian Communities

“Online churches” are Internet-based Christian communities, seeking to pursue worship, discussion, friendship, teaching, support, proselytisation and other key religious goals through computer-mediated communication. These online churches are one example of “online religion”, a new kind of digital religious practice that promises to transform worship, authority, community and the construction of identity. This thesis examines five online churches, representing diverse media, theological traditions, leadership structures and forms of external oversight. Each has created a sizeable congregation and offers forms of worship and community online. I used ethnographic methods to examine these churches with particular attention to media, worship, community and leadership. I conducted long-term participant observation over the three years of my research, taking part in online and offline activities whenever possible, speaking informally with as many people as possible and interviewing over 100 leaders and members. Survey data and other written materials were also studied where available, including media reports, participant accounts and online blog posts. My research suggested seven important themes present in each group: mass appeal, the formation of community, spiritual experience, the replication of familiar elements of architecture, liturgy and organisation, the prevalence of local churchgoing among online participants, patterns of internal control and systems of external oversight. Each case study demonstrates the very different negotiations of those themes at work in each group. In my final chapter, I bring together threads and insights from each case study according to four key dimensions of one common theme: the relationship between digital and everyday life. Online churches deliberately replicate familiar elements of everyday activity, become part of the everyday, remain carefully distinct from the everyday and become distinctively digital. We must attend to all four of these layers to adequately understand and evaluate what takes place online, and what role that online activity plays in everyday religious lives

Economics of managing acid soils in dryland mixed cropping systems: comparing gross margins with whole-farm analysis derived using a business process model

A 12-year experiment designed to show the benefits of applying lime to acid soils when growing annual pasture, perennial pasture, and annual crops in rotations with annual or perennial pastures, provides the context for comparing methods of economic analysis. In this study enterprise gross margins are compared with whole-farm cumulative monthly cash flows derived using a business process model. The current study gave gross margins comparable with those of a recently published study based on the first 12 years of the same field experiment at Book Book near Wagga Wagga in southern NSW (Li et al., 2010). Both gross margin analyses indicated positive results for all treatments. However, because key fixed and capital cost items were not taken into account in the gross margin analysis the financial benefits of the treatments were overstated. In the whole-farm analysis, a full set of accounts (including fixed and capital costs) was developed for the experimental combinations of prime lamb and dryland cropping enterprises and used to generate a monthly cash flow sequence for each treatment over the 12-year term of the experiment. This full financial analysis, where all costs are included, showed all mixed treatments (cropping and grazing) accumulated unsustainable losses over the period of the trial. The grazing-only treatments generated positive cash lows over the 12 year period, but 2 accumulated high levels of debt in the initial years. None of these outcomes were predicted by gross margins, which were consistently positive for all treatments. This paper concludes that the analysis of trial results benefits from interpretation in the context of whole-farm analysis, verified by district experience. Relying on gross margin analysis alone would have supported loss-making outcomes in this trial. This conclusion has important ramifications for analysis of all systems trials.Agribusiness,

Application of Dyes in Nonlinear Optical Materials

An outline of some azobenzene derivatives which are being used in ICI as the basis for new nonlinear optical materials is presented

Chandra Grating Spectroscopy of the X-ray Binary 4U 1700-37 in a Flaring State

Chandra X-ray Observatory grating spectra of the supergiant X-ray Binary 4U 1700-37 reveal emission lines from hydrogen and helium-like S, Si, Mg, and Ne in the 4-13 A range. The spectrum also shows fluorescent lines from S, Si, and a prominent Fe K alpha line at 1.94 A. The lines contribute to the previously unaccounted "soft excess" in the flux in this range at orbital phi~0.7. The X-ray source was observed during intermittent flaring, and the strengths of the lines vary with the source state. The widths of the lines (FWHM approximately 1000-2000 km/s) can result from either Compton scattering or Doppler shifts. Power spectra of the hard X-rays show red noise and the soft X-rays and lines show in addition quasiperiodic oscillations (QPOs) and a power-spectral break. Helium-like triplets of Si and Mg suggest that the gas is not in a pure photoionization equilibrium. We discuss whether resonant scattering could affect the line ratios or whether a portion of the wind may be heated to temperatures T~10^6 K.Comment: 43 pages, 12 figures (4 in color), submitted to The Astrophysical Journa

Evidence of Segregated Spawning in a Single Marine Fish Stock: Sympatric Divergence of Ecotypes in Icelandic Cod?

There is increasing recognition of intraspecific diversity and population structure within marine fish species, yet there is little direct evidence of the isolating mechanisms that maintain it or documentation of its ecological extent. We analyzed depth and temperature histories collected by electronic data storage tags retrieved from 104 Atlantic cod at liberty ≥1 year to evaluate a possible isolating mechanisms maintaining population structure within the Icelandic cod stock. This stock consists of two distinct behavioral types, resident coastal cod and migratory frontal cod, each occurring within two geographically distinct populations. Despite being captured together on the same spawning grounds, we show the behavioral types seem reproductively isolated by fine-scale differences in spawning habitat selection, primarily depth. Additionally, the different groups occupied distinct seasonal thermal and bathymetric niches that generally demonstrated low levels of overlap throughout the year. Our results indicate that isolating mechanisms, such as differential habitat selection during spawning, might contribute to maintaining diversity and fine-scale population structure in broadcast-spawning marine fishes

Modern optical astronomy: technology and impact of interferometry

The present `state of the art' and the path to future progress in high spatial resolution imaging interferometry is reviewed. The review begins with a treatment of the fundamentals of stellar optical interferometry, the origin, properties, optical effects of turbulence in the Earth's atmosphere, the passive methods that are applied on a single telescope to overcome atmospheric image degradation such as speckle interferometry, and various other techniques. These topics include differential speckle interferometry, speckle spectroscopy and polarimetry, phase diversity, wavefront shearing interferometry, phase-closure methods, dark speckle imaging, as well as the limitations imposed by the detectors on the performance of speckle imaging. A brief account is given of the technological innovation of adaptive-optics (AO) to compensate such atmospheric effects on the image in real time. A major advancement involves the transition from single-aperture to the dilute-aperture interferometry using multiple telescopes. Therefore, the review deals with recent developments involving ground-based, and space-based optical arrays. Emphasis is placed on the problems specific to delay-lines, beam recombination, polarization, dispersion, fringe-tracking, bootstrapping, coherencing and cophasing, and recovery of the visibility functions. The role of AO in enhancing visibilities is also discussed. The applications of interferometry, such as imaging, astrometry, and nulling are described. The mathematical intricacies of the various `post-detection' image-processing techniques are examined critically. The review concludes with a discussion of the astrophysical importance and the perspectives of interferometry.Comment: 65 pages LaTeX file including 23 figures. Reviews of Modern Physics, 2002, to appear in April issu

The Role of Genetic Variation Near Interferon-Kappa in Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by increased type I interferons (IFNs) and multiorgan inflammation frequently targeting the skin. IFN-kappa is a type I IFN expressed in skin. A pooled genome-wide scan implicated the IFNK locus in SLE susceptibility. We studied IFNK single nucleotide polymorphisms (SNPs) in 3982 SLE cases and 4275 controls, composed of European (EA), African-American (AA), and Asian ancestry. rs12553951C was associated with SLE in EA males (odds ratio = 1.93, P = 2.5 × 10−4), but not females. Suggestive associations with skin phenotypes in EA and AA females were found, and these were also sex-specific. IFNK SNPs were associated with increased serum type I IFN in EA and AA SLE patients. Our data suggest a sex-dependent association between IFNK SNPs and SLE and skin phenotypes. The serum IFN association suggests that IFNK variants could influence type I IFN producing plasmacytoid dendritic cells in affected skin