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Democratic countries, such as Australia, face the dilemma of preserving public and national security without sacrificing fundamental freedoms. In the context where the rule of law is an underlying assumption of the constitutional framework, Emergency Powers in Australia provides a succinct analysis of the sorts of emergency which have been experienced in Australia and an evaluation of the legal weapons available to the authorities to cope with these emergencies. It analyses the scope of the defence power to determine the constitutionality of federal legislation to deal with wartime crises and the 'war' on terrorism, the extent of the executive power and its relationship to the prerogative, the deployment of the defence forces in aid of the civil power, the statutory frameworks regulating the responses to civil unrest, and natural disasters. The role of the courts when faced with challenges to the invocation of emergency powers is explained and analysed.
Red Supergiant Stars (RSGs) are important probes of stellar and chemical evolution in star-forming environments. They represent the brightest near-IR stellar components of external galaxies and probe the most recent stellar population to provide robust, independent abundance estimates. The Local Group dwarf irregular galaxy, NGC6822, is a reasonably isolated galaxy with an interesting structure and turbulent history. Using RSGs as chemical abundance probes, we estimate metallicities in the central region of NGC6822, finding a suggestion of a metallicity gradient (in broad agreement with nebular tracers), however, this requires further study for confirmation. With intermediate resolution Multi-object spectroscopy (from e.g. KMOS, EMIR, MOSFIRE) combined with state-of-the-art stellar model atmospheres, we demonstrate how RSGs can be used to estimate stellar abundances in external galaxies. In this context, we compare stellar and nebular abundance tracers in NGC 6822 and by combining stellar and nebular tracers we estimate an abundance gradient of −0.18 ± 0.05 dex/kpc.
The time at which the Laurentide Ice Sheet reached its maximum extent and subsequently retreated from its terminal moraine in New Jersey has been constrained by bracketing radiocarbon ages on preglacial and postglacial sediments. Here, we present measurements of in situ produced 10Be and 26Al in 16 quartz-bearing samples collected from bedrock outcrops and glacial erratics just north of the terminal moraine in north-central New Jersey; as such, our ages represent a minimum limit on the timing of ice recession from the moraine. The data set includes field and laboratory replicates, as well as replication of the entire data set five years after initial measurement. We find that recession of the Laurentide Ice Sheet from the terminal moraine in New Jersey began before 25.2±2.1 ka (10Be, n=16, average, 1 standard deviation). This cosmogenic nuclide exposure age is consistent with existing limiting radiocarbon ages in the study area and cosmogenic nuclide exposure ages from the terminal moraine on Martha’s Vineyard ~300 km to the northeast. The age we propose for Laurentide Ice Sheet retreat from the New Jersey terminal position is broadly consistent with regional and global climate records of the last glacial maximum termination and records of fluvial incision.
The subsurface exploration of other planetary bodies can be used to unravel their geological history and assess their habitability. On Mars in particular, present-day habitable conditions may be restricted to the subsurface. Using a deep subsurface mine, we carried out a program of extraterrestrial analog research – MINe Analog Research (MINAR). MINAR aims to carry out the scientific study of the deep subsurface and test instrumentation designed for planetary surface exploration by investigating deep subsurface geology, whilst establishing the potential this technology has to be transferred into the mining industry. An integrated multi-instrument suite was used to investigate samples of representative evaporite minerals from a subsurface Permian evaporite sequence, in particular to assess mineral and elemental variations which provide small-scale regions of enhanced habitability. The instruments used were the Panoramic Camera emulator, Close-Up Imager, Raman spectrometer, Small Planetary Linear Impulse Tool, Ultrasonic drill and handheld X-ray diffraction (XRD). We present science results from the analog research and show that these instruments can be used to investigate in situ the geological context and mineralogical variations of a deep subsurface environment, and thus habitability, from millimetre to metre scales. We also show that these instruments are complementary. For example, the identification of primary evaporite minerals such as NaCl and KCl, which are difficult to detect by portable Raman spectrometers, can be accomplished with XRD. By contrast, Raman is highly effective at locating and detecting mineral inclusions in primary evaporite minerals. MINAR demonstrates the effective use of a deep subsurface environment for planetary instrument development, understanding the habitability of extreme deep subsurface environments on Earth and other planetary bodies, and advancing the use of space technology in economic mining.
Molecular assays are often implemented by weed scientists for detection of
herbicide-resistant individuals; however, the utility of these assays can be
limited if multiple mechanisms of evolved resistance exist. Waterhemp
resistant to protoporphyrinogen oxidase (PPO)– inhibiting herbicides is
conferred by a target-site mutation in PPX2L (a gene coding
for PPO), resulting in the loss of a glycine at position 210 (ΔG210). This
ΔG210 mutation of PPX2L is the only known mechanism
responsible for PPO-inhibitor resistance (PPO-R) in waterhemp from five
states (Illinois, Indiana, Iowa, Kansas, and Missouri); however, a limited
number of populations have been tested, especially in Illinois. To verify
the ubiquity of the ΔG210 in PPO-R waterhemp populations in Illinois, a
previously published allele-specific PCR (asPCR) was used for the detection
of the ΔG210 mutation to associate this mutation with phenotypic resistance
in 94 Illinois waterhemp populations. The ΔG210 mutation was detected in all
populations displaying phenotypic resistance to lactofen (220 g ai
ha−1), indicating the deletion is likely the only mechanism of
resistance. With evidence that the ΔG210 mutation dominates PPO-R waterhemp
biotypes, molecular detection techniques have considerable utility.
Unfortunately, the previously published asPCR is time consuming, very
sensitive to PCR conditions, and requires additional steps to eliminate the
possibility of false negatives. To overcome these limitations, a streamlined
molecular method using the TaqMan® technique was developed, utilizing
allele-specific, fluorescent probes for high-throughput, robust
discrimination of each allele (resistant and susceptible) at the 210th amino
acid position of PPX2L.