Uptake of branched-chain alpha-keto acids in \u3ci\u3eBacillus subtilis\u3c/i\u3e

Bacillus subtilis has a constitutive system for the uptake of alpha-keto-beta-methylvalerate, alpha-ketoisovalerate, and (probably) alpha-ketoisocaproate. A mutation, kauA1, which blocks the uptake of alpha-keto-beta-methylvalerate and alpha-ketoisovalerate, is located between metB and citK on the B. subtilis chromosome

Election Flops on YouTube

In an election campaign as drawn out as this, you'd have to have excellent memory to remember the hype around John Howard's use of YouTube to make policy announcements. Some months ago, the media were all over the story - but unfortunately for the Prime Minister, much like the widely-predicted poll 'narrowing', the YouTube effect has been missing in action

Beyond Gotcha: Blogs as a Space for Debate

The mainstream media and critics of Web 2.0’s "cult of the amateur" often suggest that blogs and citizen journalism will never replace their mainstream counterparts because they "don’t break stories". Notwithstanding the fundamental furphy – who ever said anything about "replacing" the MSM anyway? – there is some truth in this. It goes without saying that most bloggers don’t have the resources, pulling power or proximity to the pollies to do much original political reporting: this is something that most sensible public affairs bloggers concede. (Though how often the mainstream media really break stories – as against exploiting deliberate, calculated ‘leaks’ from party spinsters – is a separate question.

FINANCIAL INTERMEDIATION IN AGRICULTURE: A SUGGESTED ANALYTICAL MODEL

Agricultural Finance,

Blogging outside the Echo Chamber

In the current political climate, it's no surprise that a number of sessions at the recent Australian Blogging Conference at Queensland University of Technology in Brisbane focussed on the potential for blogs and other citizen journalism sites to impact on political news and punditry. In a previous article, we've already noted the continuing skirmishes between psephologist bloggers and the political commentators, whose rather unscientific interpretation of opinion poll results that some bloggers have challenged fervently

A photospheric metal line profile analysis of hot DA white dwarfs with circumstellar material

Some hot DA white dwarfs have circumstellar high ion absorption features in their spectra, in addition to those originating in the photosphere. In many cases, the line profiles of these absorbing components are unresolved. Given the importance of the atmospheric composition of white dwarfs to studies of stellar evolution, extra-solar planetary systems and the interstellar medium, we examine the effect of including circumstellar line profiles in the abundance estimates of photospheric metals in six DA stars. The photospheric C and Si abundances are reduced in five cases where the circumstellar contamination is strong, though the relative weakness of the circumstellar Si IV absorption introduces minimal contamination, resulting in a small change in abundance. The inability of previous, approximate models to reproduce the photospheric line profiles here demonstrates the need for a technique that accounts for the physical line profiles of both the circumstellar and photospheric lines when modelling these blended absorption features.Comment: 7 pages, 5 figues, 3 tables, accepted for publication in MNRA

The Role of Social Capital in the Industrialization of the Food System

Selfishness of preferences alone will not support the coordination necessary for the industrialization of the food system. Social capital relationships of mutual sympathy (caring) yield socio-emotional goods that are important in the more personal business world of evolving incomplete contracts and alliances involving input suppliers, processors, and labor. Relationships are also critical when consumers are buying image as well as physical products. Management and policy alternatives constitute investment in social capital that can affect opportunism, risk, loyalty, and trust.Agricultural Finance,

Cloud cover determination in polar regions from satellite imagery

A definition is undertaken of the spectral and spatial characteristics of clouds and surface conditions in the polar regions, and to the creation of calibrated, geometrically correct data sets suitable for quantitative analysis. Ways are explored in which this information can be applied to cloud classifications as new methods or as extensions to existing classification schemes. A methodology is developed that uses automated techniques to merge Advanced Very High Resolution Radiometer (AVHRR) and Scanning Multichannel Microwave Radiometer (SMMR) data, and to apply first-order calibration and zenith angle corrections to the AVHRR imagery. Cloud cover and surface types are manually interpreted, and manual methods are used to define relatively pure training areas to describe the textural and multispectral characteristics of clouds over several surface conditions. The effects of viewing angle and bidirectional reflectance differences are studied for several classes, and the effectiveness of some key components of existing classification schemes is tested