Constituting Australia's International Wireless Service: 1901-1922

This study is focused on the origins of the 1922 agreement between the Commonwealth government and Amalgamated Wireless (Australasia) to establish a wireless communications service between Australia and Britain. This agreement, which saw a partnership between the government and Australia’s principal wireless firm, represented a dramatic departure from the preceding history of Australian communications, which had hitherto been organised around the principle of government monopoly. The thesis explores the causes of this paradigmatic shift in policy through an analysis of wireless’ history in Australia from its origins to the enactment of the 1922 agreement. It is principally based on analysis of primary documents from the collections of the Postmaster-General’s, Prime Minister’s, and Navy departments held by the National Archives of Australia. The thesis finds that the 1922 agreement reflected the complex interaction of large, underlying structural forces and small, immediate factors. In relation to the former category, there were strong and constant international influences on domestic policymaking, related to the geopolitical dimensions of wireless and Australia’s place in the British Empire. The 1922 agreement also bore the indelible imprint of the Great War. One wartime development was the power accumulated by Prime Minister Hughes during the conflict, who became the leading advocate of the agreement within the government. Another was the economic disruption unleashed by the conflict, which spurred a rise in economic nationalism and efforts to promote the development of industries of strategic significance within Australia. In addition to its consideration of structural influences, the thesis uses Multiple Streams Analysis to examine the process through which the agreement became enacted as policy. Multiple Streams Analysis is a model of policymaking which shows how the actions of individuals and groups, political conditions, and timing combine to produce policy outcomes. Overall, the thesis argues that major shifts in policy cannot be solely attributed to the actions of interested groups or other powerful actors, and that it is necessary to situate those actions within a dynamic process of policymaking that is given shape by a wider context, and in which other factors such as framing and timing are pivotal to the outcome. It also demonstrates the value of policymaking theory, such as Multiple Streams Analysis, to understanding major historical policy decisions

Effects of Wind on Falling Drops

Soil erosion studies have proceeded along two basic paths in-so-far as erosion by water is concerned: 1. the measurement of soil loss and runoff caused by natural rainstorms, with pertinent characteristics of those storms and 2. The measurement of such losses when caused by artificially produced storms of arbitrarily selected characteristics. The first provides the measure for the magnitude and variability of storms as they actually occur in a given, as well as accurate measurement of losses produced by a particular storm type and intensity on a given condition of plots. The second type of storm can be produced almost any time and has the advantage, therefor, of greatly decreasing the time involved in getting an answer. A disadvantage is the great difficulty in accurately simulating any given storm type. Wind may have several effects on the simulation of rainfall or for that matter, on natural rainfall: (1) it distorts the location of the drop impact from the intended target area to some point downwind. (2) Because drops drift in the wind, they gain a horizontal velocity. Within a small plot area, wind drift may be sufficient to remove appreciable quantities to water from the test area, as wind-borne mist of fine droplets. Quantitative data concerning these effects is minimal. To gain this information, this study was conducted

Metallation and mismetallation of iron and manganese proteins in vitro and in vivo: the class I ribonucleotide reductases as a case study

How cells ensure correct metallation of a given protein and whether a degree of promiscuity in metal binding has evolved are largely unanswered questions. In a classic case, iron- and manganese-dependent superoxide dismutases (SODs) catalyze the disproportionation of superoxide using highly similar protein scaffolds and nearly identical active sites. However, most of these enzymes are active with only one metal, although both metals can bind in vitro and in vivo. Iron(II) and manganese(II) bind weakly to most proteins and possess similar coordination preferences. Their distinct redox properties suggest that they are unlikely to be interchangeable in biological systems except when they function in Lewis acid catalytic roles, yet recent work suggests this is not always the case. This review summarizes the diversity of ways in which iron and manganese are substituted in similar or identical protein frameworks. As models, we discuss (1) enzymes, such as epimerases, thought to use Fe[superscript II] as a Lewis acid under normal growth conditions but which switch to Mn[superscript II] under oxidative stress; (2) extradiol dioxygenases, which have been found to use both Fe[superscript II] and Mn[superscript II], the redox role of which in catalysis remains to be elucidated; (3) SODs, which use redox chemistry and are generally metal-specific; and (4) the class I ribonucleotide reductases (RNRs), which have evolved unique biosynthetic pathways to control metallation. The primary focus is the class Ib RNRs, which can catalyze formation of a stable radical on a tyrosine residue in their β2 subunits using either a di-iron or a recently characterized dimanganese cofactor. The physiological roles of enzymes that can switch between iron and manganese cofactors are discussed, as are insights obtained from the studies of many groups regarding iron and manganese homeostasis and the divergent and convergent strategies organisms use for control of protein metallation. We propose that, in many of the systems discussed, “discrimination” between metals is not performed by the protein itself, but it is instead determined by the environment in which the protein is expressed.National Institutes of Health (U.S.) (Grant GM81393

Use of Field Experiments in Soil Erosion Research

Experiments have a long tradition in geomorphology because of the need, or desire, to reduce complexity and thus simulate otherwise unattainable conditions. Sensu stricto, experiments involve controlled procedures that are carried out with the aim of testing a hypothesis. The challenge for designing an experiment in order to meet the expectations of the researcher lies in identifying its location in the triangle of precision versus realism versus generalism (e.g., Kuhn, 2014). By their own virtue, experiments aim to be more precise than nature, or rather, what can be observed in nature. This necessitates a reductionist, or simplified approach, which can frequently place the representativeness of the experiment, and thus the general relevance of the results to real-world scenarios into question (e.g., Bryan 1990). For instance, selecting a suitable plot size and rainfall intensity to perform rainfall simulations illustrates this challenge and will be one of the issues discussed in the case study presented in this chapter. In environmental sciences, the term “experiment” is commonly used in a somewhat wider context than has typically been applied in the more traditional, or “natural,” sciences. The reason for this is the compromise that has to be made in order to meet a position in the precision–realism–generalism triangle that generates an answer to the question being addressed by the experiment (Slaymaker, 1991). Further limitations arise from the field situation, as these can typically limit the level of control when compared to a laboratory experiment. Therefore, three broad aims of field experiments in geomorphology can be identified: 1. Actual experiments that aim to test one or more hypotheses on the interaction of one or more components within a landscape system. 2. Process-rate measurements in the field in order to quantify a conceptual model or test the relevance of a particular process in a given landscape system