1,745 research outputs found
Stabilizing the forming process in unipolar resistance switching using an improved compliance current limiter
The high reset current IR in unipolar resistance switching now poses major
obstacles to practical applications in memory devices. In particular, the first
IR-value after the forming process is so high that the capacitors sometimes do
not exhibit reliable unipolar resistance switching. We found that the
compliance current Icomp is a critical parameter for reducing IR-values. We
therefore introduced an improved, simple, easy to use Icomp-limiter that
stabilizes the forming process by drastically decreasing current overflow, in
order to precisely control the Icomp- and subsequent IR-values.Comment: 15 pages, 4 figure
New Russulaceae species in south-east Queensland
Russula species are ectomycorrhizal basidiomycetes common throughout Australian woodlands. Molecular and morphological examination of Russula specimens from various sites in South-east Queensland has uncovered a number of phylogenetically diverse and potentially undescribed specimens. At this stage, most of these remain as individual specimens. However, several specimens have been grouped into project species. In this presentation, two potentially new species of Russula will be described. Both species are widespread on red to black clay soils in the Toowoomba region and appear to be phylogenetically related to each other. Project species 1 has a white stipe which developed a pink flush after collection and red to pink centrally depressed cap with white gills. The spores of this species were subglobose, white and ornamented with amyloid warts connected in short chains. The second species, project species 3, is macroscopically similar, differing with its larger size, purple-pink cap colour, and rougher cap texture. Its spores are globose to subglobose, white and ornamented with small amyloid warts connected in short chains. Continued molecular and morphological studies of the Russula species of South-east Queensland may uncover more novel Australian species
Investigation of the anti-microbial properties of endophytes from Santalum lanceolatum
Santalum lanceolatum is a native Australian plant which has a history of prior use by the indigenous Australian population to treat infections. This project looks at the fungal endophytes present in Santalum lanceolatum and whether bioactive compounds from the endophytic fungi may be able to be used as antimicrobials. At this stage two sites in the Darling Downs region have been sampled with both sites producing a wide variety of endophytes from the plant tissue when grown on potato dextrose agar. One site has already been screened on Sensitest agar against ATCC type strains of Staphylococcus aureus, Serratia
marcescens, Escherichia coli and Candida albicans, with no observable inhibition as to the growth of these pathogens. If any bioactive compounds are found to be effective, then the molecular structure of the compound is to be identified along with the sequencing of the ITSDNA of the endophytic fungi from which it came. Work on this project will be continuing throughout 2014
Aboriginal uses of seaweeds in temperate Australia: an archival assessment
This is the author accepted manuscript. The final version is available from Springer Verlag via the DOI in this record.Global demand for seaweed has increased dramatically over recent decades and the potential for seaweed aquaculture to address issues around food security and climate-change mitigation are being recognised. Australia is a global hotspot for seaweed biodiversity with a rich, diverse Indigenous history dating back 65,000 years, including an extensive traditional knowledge of Australian natural resources. In our present review of archival literature, we explored the contemporary and historical uses and cultural significance of seaweeds to Indigenous Australians. We found records of seaweed use by Indigenous Saltwater Australians (Australian Aboriginal peoples from coastal areas across the nation who are the Traditional Owners/Guardians and custodians of the lands and waters characterised by saltwater environment) for a variety of purposes including cultural activities, ceremonial activities, medicinal uses, clothing, cultural history, food, fishing, shelter and domestic uses. Species-specific records were rarely recorded (and/or accurately translated) in the archival literature, with the exception of the use of the fucoid bull kelp, Durvillaea potatorum, which was prevalent. Our research is a step forward in the important task of recovering and conserving Indigenous Australian knowledge and customary traditions surrounding coastal resource use. Unlocking this knowledge creates opportunities for the continuance and revitalization of traditional customary practises that may enable innovative Indigenous business activities and product creation, based around food, sustainable natural-fibre technologies and health. Such research also has the potential to enhance a developing Australian seaweed industry by guiding species selection, preparation, use and sustainable resource management. We recommend our findings are used to inform the direction and locations of further research conducted in conjunction with Indigenous coastal communities in Australia’s temperate regions, to explore in more detail the Indigenous Australian’s historical heritage associated with coastal seaweed resources and their uses
Molecular dynamics simulations of oxide memory resistors (memristors)
Reversible bipolar nano-switches that can be set and read electronically in a
solid-state two-terminal device are very promising for applications. We have
performed molecular-dynamics simulations that mimic systems with oxygen
vacancies interacting via realistic potentials and driven by an external bias
voltage. The competing short- and long-range interactions among charged mobile
vacancies lead to density fluctuations and short-range ordering, while
illustrating some aspects of observed experimental behavior, such as memristor
polarity inversion.Comment: 15 pages, 5 figure
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