Science

Publication Search Results

Now showing 1 - 10 of 11
  • (1998) Bradley, Peter; Rozenfeld, Anatoly; Lee, Kevin; Jamieson, Dana; Heiser, Gernot; Satoh, S
    Journal Article
    The first results obtained using a SOI device for microdosimetry applications are presented. Microbeam and broadbeam spectroscopy methods are used for determining minority carrier lifetime and radiation damage constants. A spectroscopy model is presented which includes the majority of effects that impact spectral resolution. Charge collection statistics were found to substantially affect spectral resolution. Lateral diffusion effects significantly complicate charge collection

  • (1996) Yu, David; Munroe, Paul; Bandyopadhyay, Srikanta; Mouritz, A
    Journal Article
    The microstructural development during annealing of a cold-deformed 6061Al metal matrix composite (MMC) reinforced with either 3 or 20 mgrm diameter SiC particles has been investigated. The composites were compressed to low (< 10%) levels of strain and then annealed at either 350 or 450°C for different times. Microstructure examination was carried out by transmission electron microscopy and optical microscopy. The results reveal that prior grain boundaries and constituent particles are the dominant sites for recrystallization in both composites, although some nucleation was observed adjacent to the larger SiC particles. The concurrent presence of Mg2Si precipitates affected the progress of recrystallization.

  • (2000) Cotera, Angela; Simpson, John; Erickson, E; Colgan, Sean; Burton, Michael; Allen, David
    Journal Article

  • (1998) Davies, Richard; Forbes, Duncan; Ryder, Stuart; Ashley, Michael; Burton, Michael; Storey, John; Allen, Lori; Ward, Michael; Norris, Ray
    Journal Article
    We have imaged the Circinus galaxy in the near-infrared [Fe ii] 1.64-μm and H2 2.12-μm lines, and derived velocity maps for the emission. The morphologies are strikingly different, but the velocity maps are very similar and consistent with simple rotation. We also present new radio continuum maps at 3 and 6 cm, which show a partially resolved nucleus with a flat spectral index. This suggests free–free absorption rather than self-absorption in a compact source. There is some evidence of radio jets close to the nucleus. The H2 emission, rather than the [Fe ii] as in NGC 1068, is extended along the jet axis and may be excited by jet-induced shocks either in a low-density medium or with rather slow shock speeds (v≲50 km s−1). We find that the star formation in the ring 10 arcsec from the nucleus began less than a few ×107 yr ago. Nearer the AGN, perhaps in and around the inferred torus, we detect extended [Fe ii] emission (including one prominent peak about 2 arcsec north of the AGN which could be due to a single young remnant), from which we derive a modest star formation rate of <1 M⊙ yr−1.

  • (1997) Chrysostomou, Antonio; Burton, Michael; Axon, David J.; Brand, Peter W. J. L.; Hough, J. H.; Bland-Hawthorn, Joss; Geballe, T. R.
    Journal Article

  • (2013) Williams, Alishia; Lau, Gloria; Grisham, Jessica
    Journal Article
    Background and Objectives: Thought-action fusion (TAF), or maladaptive cognitions regarding the relationship between mental events and behaviours, has been implicated in the development and maintenance of obsessive-compulsive disorder (OCD). As some religions promote TAF-like appraisals, it has been proposed that religiosity may play a role in the transformation of normally occurring intrusive thoughts into clinically distressing obsessions. No research, however, has experimentally investigated the mediating role of TAF on the relationship between religiosity and OC symptoms. Methods: 85 Christian, Jewish, and Atheist/Agnostic participants were exposed to an experimental thought-induction protocol and reported on their associated levels of distress, guilt, feelings of responsibility, and urge to suppress target intrusions experienced during a 5-minute monitoring period. Participants also completed measures of obsessive-compulsive symptomatology, TAF beliefs, and general psychopathology. Results: Using PROCESS and bootstrapping analyses, a test of the conditional indirect effects of religiosity on obsessive-compulsive symptoms revealed that Christianity moderated the effects of religiosity on moral TAF beliefs, which in turn mediated the relationship between religiosity and obsessive-compulsive symptoms. Furthermore, in the Christian group, moral TAF beliefs mediated the relationship between religiosity and ratings of guilt and responsibility following the experimental protocol. Limitations: The use of university students with moderate levels of religiosity. Conclusions: Collectively the results suggest that obsessional thinking is not attributable to religion per se, but that teachings underlying certain religious doctrines may fuel TAF beliefs that are implicated in the maintenance of OCD.

  • (2012) Funnell, Alister; Norton, Laura; Mak, Ka Sin; Burdach, John; Artuz, Crisbel; Twine, Natalie; Wilkins, Marc; Hung, TT; Perdomo, Jose; Power, Carl; Koh, P; Bell Anderson, Kim; Orkin, S; Fraser, Stuart; Perkins, Andrew; Pearson, Richard; Crossley, Merlin
    Journal Article
    The CACCC-box binding protein erythroid Krüppel-like factor (EKLF/KLF1) is a master regulator that directs the expression of many important erythroid genes. We have previously shown that EKLF drives transcription of the gene for a second KLF, basic Krüppel-like factor, or KLF3. We have now tested the in vivo role of KLF3 in erythroid cells by examining Klf3 knockout mice. KLF3-deficient adults exhibit a mild compensated anemia, including enlarged spleens, increased red pulp, and a higher percentage of erythroid progenitors, together with elevated reticulocytes and abnormal erythrocytes in the peripheral blood. Impaired erythroid maturation is also observed in the fetal liver. We have found that KLF3 levels rise as erythroid cells mature to become TER119(+). Consistent with this, microarray analysis of both TER119(-) and TER119(+) erythroid populations revealed that KLF3 is most critical at the later stages of erythroid maturation and is indeed primarily a transcriptional repressor. Notably, many of the genes repressed by KLF3 are also known to be activated by EKLF. However, the majority of these are not currently recognized as erythroid-cell-specific genes. These results reveal the molecular and physiological function of KLF3, defining it as a feedback repressor that counters the activity of EKLF at selected target genes to achieve normal erythropoiesis.

  • (1998) Grossel, M; Hamilton, D; Fuller, John; Millan-Barios, E; Hibbert, D. Brynn
    Journal Article

  • (2014) Lorenz, Ruth; Pitman, Andrew; Donat, Markus; Hirsch, Annette; Kala, Jatin; Kowalczyk, E; Law, R; Srbinovsky, J
    Journal Article
    Climate extremes, such as heat waves and heavy precipitation events, have large impacts on ecosystems and societies. Climate models provide useful tools for studying underlying processes and amplifying effects associated with extremes. The Australian Community Climate and Earth System Simulator (ACCESS) has recently been coupled to the Community Atmosphere Biosphere Land Exchange (CABLE) model. We examine how this model represents climate extremes derived by the Expert Team on Climate Change Detection and Indices (ETCCDI) and compare them to observational data sets using the AMIP framework. We find that the patterns of extreme indices are generally well represented. Indices based on percentiles are particularly well represented and capture the trends over the last 60 years shown by the observations remarkably well. The diurnal temperature range is underestimated, minimum temperatures (T-MIN) during nights are generally too warm and daily maximum temperatures (T-MAX) too low in the model. The number of consecutive wet days is overestimated, while consecutive dry days are underestimated. The maximum consecutive 1-day precipitation amount is underestimated on the global scale. Biases in T-MIN correlate well with biases in incoming longwave radiation, suggesting a relationship with biases in cloud cover. Biases in T-MAX depend on biases in net shortwave radiation as well as evapotranspiration. The regions and season where the bias in evapotranspiration plays a role for the T-MAX bias correspond to regions and seasons where soil moisture availability is limited. Our analysis provides the foundation for future experiments that will examine how land-surface processes contribute to these systematic biases in the ACCESS modelling system.

  • (2013) Lunt, D; Abe-Ouchi, A; Bakker, P; Berger, A; Braconnot, P; Charbit, S; Fischer, N; Herold, N; Jungclaus, J; Khon, V; Krebs-Kanzow, U; Langebroek, P; Lohmann, G; Nisancioglu, K; Otto-Bliesner, B; Park, W; Pleiffer, M; Phipps, Steven; Prange, M; Rachmayani, R; Renssen, H; Rosenbloom, N; Schneider, B; Stone, E; Takahashi, K; Wei, W; Yin, Q; Zhang, Z
    Journal Article
    The last interglaciation (similar to 130 to 116 ka) is a time period with a strong astronomically induced seasonal forcing of insolation compared to the present. Proxy records indicate a significantly different climate to that of the modern, in particular Arctic summer warming and higher eustatic sea level. Because the forcings are relatively well constrained, it provides an opportunity to test numerical models which are used for future climate prediction. In this paper we compile a set of climate model simulations of the early last interglaciation (130 to 125 ka), encompassing a range of model complexities. We compare the simulations to each other and to a recently published compilation of last interglacial temperature estimates. We show that the annual mean response of the models is rather small, with no clear signal in many regions. However, the seasonal response is more robust, and there is significant agreement amongst models as to the regions of warming vs cooling. However, the quantitative agreement of the model simulations with data is poor, with the models in general underestimating the magnitude of response seen in the proxies. Taking possible seasonal biases in the proxies into account improves the agreement, but only marginally. However, a lack of uncertainty estimates in the data does not allow us to draw firm conclusions. Instead, this paper points to several ways in which both modelling and data could be improved, to allow a more robust model-data comparison.