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In natural habitats, bacteria spend most of their time in some form of growth arrest. Little is known about deleterious mutations in such stages, and consequently there is limited understanding of what evolutionary events occur. In a deleterious mutation accumulation experiment in prolonged stationary phase of Escherichia coli, about 0.03 slightly deleterious mutations were observed per genome per day. This is over an order of magnitude higher than extrapolations from fast-growing cells, but in line with inferences from observations in adaptive stationary phase mutation experiments. These findings may affect understanding of bacterial evolution and the emergence of bacterial pathogenicity.
Most existing natural language interfaces to databases (Nlidbs) were designed to be used with snapshot database systems, that provide very limited facilities for manipulating time-dependent data. Consequently, most Nlidbs also provide very limited support for the notion of time. In particular, they were designed to answer questions that refer mainly to the present, and do not support adequately the mechanisms that natural language uses to express time. The database community is becoming increasingly interested in temporal database systems. These are intended to store and manipulate in a principled manner information not only about the present, but also about the past and future. When interfacing to temporal databases, it becomes crucial for Nlidbs to interpret correctly temporal linguistic mechanisms (verb tenses, temporal adverbials...
This paper describes the development and evaluation of
objective methods for testing synthetic intonation. While
subjective methods are available for assessing the quality
of synthetic intonation, such tests consume time and
resources, and are not useful for day-to-day model development.
Therefore, objective measures of F0 modelling
are necessary. Currently, objective evaluation of synthetic
intonation involves the use of Root Mean Squared Error
and Correlation. However, it is unclear how large an improvement
in either score must be before it is reflected
perceptually. It is also unclear how detailed an analysis
these metrics provide. Therefore, two other metrics are to
be tested, both of which are similar to a basic RMSE measurement.
All of the evaluation results are compared to a
perceptual study in order to determine h...
Presentation given at the Edinburgh Repository Fringe 2008 conference
Lead emitted into the environment, primarily from the combustion of leaded petrol and industrial activities, such as metal smelting and coal burning, retains the isotopic signature of the ores from which it is derived. Accordingly, it is possible, at least in principle, to distinguish sources of lead pollution via isotope ratio measurements. In this study, inductively coupled plasma mass spectrometry (ICP-MS) was used to characterise and investigate the extent of variation of lead isotope ratios in contemporary and historical environmental materials in Scotland. Reliable analytical methods were established for atomic absorption spec trometric measurement of lead, ICP-MS determination of stable lead isotopes, 208Pb, 207Pb and 206Pb, and gamma spectrometric assay of radioactive 210Pb in lake sediments and peat cores.
Leaded petrol, at...
Information Extraction (IE) based techniques have great potential to enable
companies to leverage valuable information embedded in unstructured
textual data. Such data could be exploited to help drive sales and to enhance
the customer's experience when searching or browsing for products.
Extensive research has been performed in the field of IE; however, to date
no work has been directly applied to the domain of fiction. The aim of this
study is to explore the ability of IE techniques to extract the central
characters and their relationships from the full textual content of works of
fiction. To begin our investigation, we present a collection of hypotheses
outlining our expectations in approaching and resolving these problems. We
then outline our data collection process, which resulted in the creation of a
Gold Standard conta...
Migration is becoming a major political and social issue in a global context. However,
while immigrants’ integration into the hosting society and cities has sparked research
investigations, there have been few studies focusing on how their presence affects the urban
fabric, especially their use of public open spaces and even less is known about how, and in what
way, such spaces have an impact on the immigrants themselves. The scope of this research is to
gain a better understanding of how immigrants use, perceive and experience public open spaces.
The research focuses on the case study of public open spaces in Lisbon, the capital of Portugal.
The thesis centres on the experience of first generation immigrants from the three largest
immigrant communities living in Portugal, namely, from Brazil, Cape Verde and Ukraine. These
imm...
Scientific communication used to be based on the article or the monograph. Now datasets and databases are becoming as important in some cases. Aside from their value in communication, data are also the raw stuff of the scientific record, and the basis for verifiability. So scientists need to curate the data they create, and make them available for re-use. What are the implications and effects of these changes, and what should scientists and scholars be doing about them?
Cardiac and orthopaedic diseases are significant causes of morbidity and mortality in
dogs and are therefore critical areas for veterinary research. More information regarding
the pathophysiology of these diseases, and the development of novel therapeutics are
sorely required and adult stem cells (ASCs) are a promising source of cells for both
investigation of these diseases in vitro and also potentially therapeutics in the longer
term.
ASCs are a readily available source of multipotent cells which bypass the ethical issues
surrounding embryonic stem (ES) cells. ASCs have been described in several tissues of
the body, and typically differentiate along specific cellular routes related to original
source location. This thesis investigates whether ASCs can be isolated and cultured from
the dog from two specific locations; cardia...
