Synthetically-focused surface-penetrating radar for operation from a moving vehicle

This paper reports on a research programme, started recently under DERA sponsorship, on applying synthetic focusing to an oblong horizontal stand-off array, where all the voxels in a vertical slice underneath the centre-line of the array are synthesised electronically, with the third dimension provided by the search vehicle's forward movement. This should permit a very high search rate for buried mines, in a wide range of ground conditions

Gene pyramiding as a Bt resistance management strategy: How sustainable is this strategy?

Reports on the emergence of insect resistance to Bacillus thuringiensis delta endotoxins have raiseddoubts on the sustainability of Bt-toxin based pest management technologies. Corporate industry has responded to this challenge with innovations that include gene pyramiding among others. Pyramidingentails stacking multiple genes leading to the simultaneous expression of more than one toxin in a transgenic variety. Questions have been raised on the sustainability of gene pyramiding since the use of insecticide mixtures has shown that cross resistance and/or multiple resistance can render such strategies to be less effective in the long term. Current theoretical and practical evidence in insect population genetics suggest that gene pyramiding cannot be sustained as a resistance management strategy per se. Pyramiding is useful as a strategy to broaden the range of insect pests controlled in each transgenic variety, and it still has to be deployed in tandem with Bt resistance management strategies such as crop refugia, biological pest control, temporal and spatial crop rotations among other

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency–Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research