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In the context of broad scale system changes (e.g. climate change) and the prioritisation of impact-at-scale development, there is a particular need for farming systems research (FSR) to improve our understanding of the links between systems at multiple scales. Drawing on three empirical case studies of large-scale agricultural interventions in eastern and southern Africa, we highlight problems that arise from conceiving and justifying interventions on the basis of the simple aggregation of farms into large collective systems. We review changes in the approach and concepts of FSR and point to the value of farming systems concepts that go beyond these aggregations, and find ways to capture the multi-level system dynamics that link on-farm decision making to broader political, social, and environmental changes. Recent attempts at more ac...
This paper discusses the extent to which algorithms developed for the processing of textual databases are also applicable to the processing of chemical structure databases, and vice versa. Applications discussed include: an algorithm for distribution sorting that has been applied to the design of screening systems for rapid chemical substructure searching; the use of measures of inter-molecular structural similarity for the analysis of hypertext graphs; a genetic algorithm for calculating term weights for relevance feedback searching for determining whether a molecule is likely to exhibit biological activity; and the use of data fusion to combine the results of different chemical similarity searches.
Data fusion is being increasingly used to combine the outputs of different types of sensor. This paper reviews the application of the approach to ligand-based virtual screening, where the sensors to be combined are functions that score molecules in a database on their likelihood of exhibiting some required biological activity. Much of the literature to date involves the combination of multiple similarity searches, although there is also increasing interest in the combination of multiple machine learning techniques. Both approaches are reviewed here, focusing on the extent to which fusion can improve the effectiveness of searching when compared with a single screening mechanism, and on the reasons that have been suggested for the observed performance enhancement.
This paper reviews the articles published in Volumes 2-24 of the Journal of Molecular Graphics and Modelling (formerly the Journal of Molecular Graphics), focusing on the changes that have occurred in the subject over the years, and on the most productive and most cited authors and institutions. The most cited papers are those describing systems or algorithms, but the proportion of these types of article is decreasing as more applications of molecular graphics and molecular modelling are reported.
This paper reviews the techniques available for quantifying the effectiveness of methods for molecule similarity and molecular diversity, focusing in particular on similarity searching and on compound selection procedures. The evaluation criteria considered are based on biological activity data, both qualitative and quantitative, with rather different criteria needing to be used depending on the type of data available.
The average strain state of Ge films grown on Si(111) by surfactant mediated epitaxy has been compared to the ordering of the interfacial misfit dislocation network. Surprisingly, a smaller degree of average lattice relaxation was found in films grown at higher temperature. On the other hand, these films exhibit a better ordered dislocation network. This effect energetically compensates the higher strain at higher growth temperature, leading to the conclusion that, apart from the formation of misfit dislocations, their ordering represents an important channel for lattice-strain energy relaxation.
Practical investigation of the use of mind-mapping at different
stages of the research process: eliciting, representing and
integrating knowledge.
EPSRC-funded MAGNET project (developing theoretical
models of gun crime to inform stakeholder decision-making
about interventions).
Mind-maps were particularly useful for communication within
our transdisciplinary team and brainstorming, interviews and
focus groups with a diverse range of stakeholders.
Attacks on cryptosystem implementations (e.g. security fault injection, timing analysis and differential power analysis) are amongst the most exciting developments in cryptanalysis of the past decade. Altering the internal state of a cryptosystem or profiling the system’s computational dynamics can be used to gain a huge amount of information. This paper shows how fault injection and timing analysis can be interpreted for a simulated annealing attack on Pointcheval’s Permuted Perceptron Problem (PPP) identification schemes. The work is unusual in that it concerns fault injection and timing analysis on an analysis technique. All recommended sizes of the PPP schemes are shown to be unsafe.
Professor Dowie has written an interesting and
thought provoking paper on a long lasting debate
in the literature on measuring health related
quality of life. The debate between generic and
condition specific measures (CSMs) has not
progressed a great deal with time and he is
right to question a purely psychometric approach
that currently tends to focuses on effect sizes.
He has also presented an interesting challenge
to the compromise solution suggested by a number
of psychometricians to adopt both types of
measure.
It is now clear that the 2011 Tohoku-Oki earthquake ruptured the subduction interface all the way to the Japan Trench. However, there is significant disagreement about just how much slip occurred at the trench, with most geodetic studies locating only a small fraction of the maximum slip there, whereas broadband seismic studies put the majority of the slip near the trench. Measurements of seafloor displacement near the trench also imply more slip there than is estimated by the geodetic studies. Here, by means of a joint inversion of displacement measurements and seafloor pressure data, we show that it is possible to reconcile geodetic and seismic studies and that a considerable amount of slip indeed occurred at the trench, with slip magnitudes reaching 57-74% of the maximum slip. The seafloor displacement predicted by our model agrees ...
