19683 research outputs found
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Refining the chronology of Middle/Late Pleistocene fossil assemblages in the Argentine Pampas
No full textMiddle and Late Pleistocene large and mega-mammal records of the Argentine Pampas, belonging to the Bonaerian and Lujanian Stages/Ages, have not yet been adequately dated by standard numerical radiometric methods. Reference timescales for Argentina and other South American fossil sites are mainly based on the mammalian faunal content (biostratigraphic units or biozones). We have recently dated three Middle and Late Pleistocene faunal sites located in the Buenos Aires Province using Electron Spin Resonance (ESR), U-series, Optically Stimulated Luminescence (OSL) and radiocarbon dating. The geographically distant sites (Salto de Piedra, Campo Spósito and Cascada de Paleolama) have yielded fossil assemblages representative of the Lujanian and Bonaerian Stages/Ages. Salto de Piedra, systematically excavated, records one of the most complete fossil sequences and our results indicate that it deposited between at least 127.4 ka (minimum age; Late Pleistocene, MIS 5) and 4.8–4.3 cal ka BP (Middle Holocene, MIS 1). Campo Spósito lower level (corresponding to ‘El Tala’ unit) was dated to >188 ka via ESR/U-series dating of teeth. Finally, Cascada de Paleolama Unit D, towards the base of the sequence, produced an age of 143 ± 20 ka (Late Pleistocene, MIS 5/6). The new dating results provide a crucial additional age control for the Bonaerian and Lujanian Stages/Ages, and allowed us to better identify and calibrate the limits of Equus neogeus, Megatherium americanum biozones, as well as to better constrain other index taxa that are used to construct local biostratigraphical frameworks. Our results indicate the need for a revision of the biozone schemes established for the Quaternary of Pampean region.</p
Mycologists and Virologists Align: Proposing Botrytis cinerea for Global Mycovirus Studies
No full textMycoviruses are highly genetically diverse and can significantly change their fungal host’s phenotype, yet they are generally under-described in genotypic and biological studies. We propose Botrytis cinerea as a model mycovirus system in which to develop a deeper understanding of mycovirus epidemiology including diversity, impact, and the associated cellular biology of the host and virus interaction. Over 100 mycoviruses have been described in this fungal host. B. cinerea is an ideal model fungus for mycovirology as it has highly tractable characteristics—it is easy to culture, has a worldwide distribution, infects a wide range of host plants, can be transformed and gene-edited, and has an existing depth of biological resources including annotated genomes, transcriptomes, and isolates with gene knockouts. Focusing on a model system for mycoviruses will enable the research community to address deep research questions that cannot be answered in a non-systematic manner. Since B. cinerea is a major plant pathogen, new insights may have immediate utility as well as creating new knowledge that complements and extends the knowledge of mycovirus interactions in other fungi, alone or with their respective plant hosts. In this review, we set out some of the critical steps required to develop B. cinerea as a model mycovirus system and how this may be used in the future.</p
Associations Between Psychological Features with Running Behaviour and Biomechanics in Runners with a History of Knee Surgery
No full textThis thesis is submitted in total fulfilment of the requirements for the degree of Master of Applied Science to the School of Allied Health, Human Services and Sport, La Trobe University, Victoria, Australia.</p
Pressing Evidence: Activating Khmer Rouge Archives
No full textAcross the world, non-state actors are documenting international crimes and creating archives for accountability purposes. In this article, we consider how archives and their records are ‘pressed into’ legal service. At a time of wider archive creations, we suggest the archives pertaining to the Khmer Rouge regime (1975-1979) provide insights as a compelling ‘post-accountability’ case of the continuum of archival processes. By examining four Khmer Rouge archives, we demonstrate how records are activated in legal processes across different spacetimes, and how the records themselves ‘(im)press upon’ on the legal process. In these processes, different actors seek to control the narrative of the past through archival holdings. We find that entrepreneurial justice, especially in the crucible of a legal process, can create fierce competition between actors over the economic and social capital inherent in record-keeping that is ultimately detrimental to understanding and pluralising the past.</p
Micro computed tomography analysis of barley during the first 24 hours of germination
No full textBackground: Grains make up a large proportion of both human and animal diets. With threats to food production, such as climate change, growing sustainable and successful crops is essential to food security in the future. Germination is one of the most important stages in a plant’s lifecycle and is key to the success of the resulting plant as the grain undergoes morphological changes and the development of specific organs. Micro-computed tomography is a non-destructive imaging technique based on the differing x-ray attenuations of materials which we have applied for the accurate analysis of grain morphology during the germination phase. Results: Micro Computed Tomography conditions and parameters were tested to establish an optimal protocol for the 3-dimensional analysis of barley grains. When comparing optimal scanning conditions, it was established that no filter, 0.4 degrees rotation step, 5 average frames, and 2016 × 1344 camera binning is optimal for imaging germinating grains. It was determined that the optimal protocol for scanning during the germination timeline was to scan individual grains at 0 h after imbibition (HAI) and then the same grain again at set time points (1, 3, 6, 24 HAI) to avoid any negative effects from X-ray radiation or disruption to growing conditions. Conclusion: Here we sought to develop a method for the accurate analysis of grain morphology without the negative effects of possible radiation exposure. Several factors have been considered, such as the scanning conditions, reconstruction, and possible effects of X-ray radiation on the growth rate of the grains. The parameters chosen in this study give effective and reliable results for the 3-dimensional analysis of macro structures within barley grains while causing minimal disruption to grain development
Polarisation and rheology characterisation of monoolein/water liquid crystal dynamical behaviour during high-viscosity injector extrusion
No full textHypothesis: The use of monoolein/water mixtures in serial crystallography experiments using high-viscosity injectors (HVI) results in significant departures from equilibrium behaviour. This is expected to include changes in phase, viscosity, and associated flow behaviour. It should be possible to detect these changes, in-situ, using a combination of polarisation and rheology characterisation techniques. Experiments: A systematic study was performed using monoolein, varying the water content to create a range of mixtures. Injection induced phase changes within the HVI flow were established using real-time cross-polarization measurements. Dynamic flow characteristics and viscosity was characterized by particle tracking and rheology. Findings: HVI injection induces deformation and phase changes within monoolein (MO)/water mixtures which can be detected through variations in the transmitted intensity during in-situ polarisation studies. The heterogeneity of the extruded sample results in a highly viscous cubic phase in the central region of the stream and a less viscous lamellar-rich phase at the edges adjacent to the walls. The extent of these variations depends on sample composition and injection conditions. Shear-thinning behaviour and increasing heterogeneity in the vicinity of the capillary walls under dynamic flow conditions. This is the first report observing injection induced dynamical behaviour in MO/water mixtures under realistic flow conditions
Digital welfare‐to‐work in the global south: A case of Indonesian pre‐employment card program
No full textAbstract: The worldwide movement toward digitisation in public service delivery presents a range of opportunities and risks. The potential benefits include improved efficiency, more consistent service delivery decisions and enhanced responsiveness to citizens' demand. The potential risks range from challenges in data use and privacy, to uneven service accessibility and the costly ICT investment required for digitisation. Researchers have begun to assess this important movement and its impacts. There remains a lack of in‐depth understanding of digitisation of public service delivery in developing countries. We aim to address that gap by examining a fully online welfare‐to‐work programme in a developing country, that is Indonesia's Pre‐employment Card Program. Using data collected from semi‐structured interviews with policymakers and service providers, we found evidence that digitalisation contributed to the programme's efficiency and effectiveness via, for example, automated registration processes and quick and revisable rollout. Its implementation however was not without challenges such as a digital divide among users and some technical problems. Indonesia's experiences with this fully digital programme suggest that a developing country, despite limited financial and administrative capacity, can embark on the digitalisation journey to improve their public service provision, even during the time of crisis.</p
A Phenomenological Study of Educators' Integration of Digital Technology in Reggio Emilia-inspired Pedagogies
No full textA thesis submitted in total fulfilment of the requirements for the degree of Doctor of Philosophy to the School of Education, La Trobe University, Victoria, Australia.</p
Rapid Conductometric Sensing of Chronic Kidney Disease Biomarkers: Specific and Precise Detection of Creatinine and Cystatin C in Artificial Saliva
No full textAbstract: Chronic kidney disease (CKD) has asymptomatic early stages, whereby early detection is crucial to prevent its complications and progression. Creatinine and cystatin C (cysC) assays are known for assessing kidney function but there are limited point‐of‐care diagnostics which are rapid, precise, and easy to use. Here, high resistivity silicon conductometric sensors for detection of creatinine and cysC with a 10 min sample incubation is introduced. The sensors provide resistance‐based signals that can be quantified and measured wirelessly. The sensors successfully detect creatinine and cysC in both phosphate buffer saline (PBS) and artificial saliva in the nanomolar range, being able to distinguish their critical concentrations at 8.8 and 20 nm, respectively, for diagnosis of early stage of CKD. The detection limit for both creatinine and cysC is determined as 0.01 nm which is more than 500× and 1000× times lower than critical concentrations for the two biomarkers, respectively. Finally, these sensors are incorporated into a battery‐free, miniaturized electronic device for wireless biomarker detection as a proof‐of‐concept demonstration of a point‐of‐care tool for assessing kidney functionality.</p
The Nature and Extent of Australian Law and Policy Reform on Supported Decision Making
No full textNo description supplied</p