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Party system institutionalisation in east-central Europe: empirical dimensions and tentative conclusions
The nationalisation of party systems is a topic closely related to processes of party system institutionalisation, an area that has developed its own literature and dimensions of analysis. Institutionalisation is understood to comprise four main dimensions: the growth of stability in the rules and nature of inter-party competition, the development of stable roots in society that help ensure a measure of regularity in how people vote, the acquisition of legitimacy by parties and the electoral process, and the establishment of party organisation that have an independent status and some value in their own right. The idea of party system institutionalisation was first presented by S. Mainwaring and T. Scully in 1995 and has been developed in a range of other publications, mostly by Mainwaring with a number of different contributors. It was first developed in a Latin American context but has an obvious relevance to developments in other newly democratising countries. In terms of outcomes, party system institutionalisation is understood to have a strong impact on the quality of democracy and to reduce tendencies to clientelism, political populism and the growth of anti-politics sentiments, and to foster mechanisms of democratic accountability and effective policy formulation.
Over the years, a substantial literature on the process of party system institutionalisation has been produced and, in recent years, a growing proportion of this has concerned systems in Central and Eastern Europe. This paper will, firstly, survey and evaluate some of the most recent literature with a view to establishing what light it sheds on the process in East-Central Europe and, secondly, identify and assess the key data that enable any judgement to be made on the course of this process in the region and to identify the contributions in this area of various data-bases relating to party politics
Mind the Gap: Another look at the problem of the semantic gap in image retrieval
This paper attempts to review and characterise the problem of the semantic gap in image retrieval and the attempts being made to bridge it. In particular, we draw from our own experience in user queries, automatic annotation and ontological techniques. The first section of the paper describes a characterisation of the semantic gap as a hierarchy between the raw media and full semantic understanding of the media's content. The second section discusses real users' queries with respect to the semantic gap. The final sections of the paper describe our own experience in attempting to bridge the semantic gap. In particular we discuss our work on auto-annotation and semantic-space models of image retrieval in order to bridge the gap from the bottom up, and the use of ontologies, which capture more semantics than keyword object labels alone, as a technique for bridging the gap from the top down
Quasar Microlensing at High Magnification and the Role of Dark Matter: Enhanced Fluctuations and Suppressed Saddlepoints
Contrary to naive expectation, diluting the stellar component of the lensing
galaxy in a highly magnified system with smoothly distributed ``dark'' matter
increases rather than decreases the microlensing fluctuations caused by the
remaining stars. For a bright pair of images straddling a critical curve, the
saddlepoint (of the arrival time surface) is much more strongly affected than
the associated minimum. With a mass ratio of smooth matter to microlensing
matter of 4:1, a saddlepoint with a macro-magnification of mu = 9.5 will spend
half of its time more than a magnitude fainter than predicted. The anomalous
flux ratio observed for the close pair of images in MG0414+0534 is a factor of
five more likely than computed by Witt, Mao and Schechter if the smooth matter
fraction is as high as 93%. The magnification probability histograms for
macro-images exhibit distinctly different structure that varies with the smooth
matter content, providing a handle on the smooth matter fraction. Enhanced
fluctuations can manifest themselves either in the temporal variations of a
lightcurve or as flux ratio anomalies in a single epoch snapshot of a multiply
imaged system. While the millilensing simulations of Metcalf and Madau also
give larger anomalies for saddlepoints than for minima, the effect appears to
be less dramatic for extended subhalos than for point masses. Morever,
microlensing is distinguishable from millilensing because it will produce
noticeable changes in the magnification on a time scale of a decade or less.Comment: As accepted for publication in ApJ. 17 pages. Substantial revisions
include a discussion of constant M/L models and the calculation of a
"photometric" dark matter fraction for MG0414+053
Order, Please! Uncertainty in the Ordinal-Level Classification of Chlorophyceae
Background. Chlorophyceae is one of three most species-rich green algal classes and also the only class in core Chlorophyta whose monophyly remains uncontested as gene and taxon sampling improves. However, some key relationships within Chlorophyceae are less clear-cut and warrant further investigation. The present study combined genome-scale chloroplast data and rich sampling in an attempt to resolve the ordinal classification in Chlorophyceae. The traditional division into Sphaeropleales and Volvocales (SV), and a clade containing Oedogoniales, Chaetopeltidales, and Chaetophorales (OCC) was of particular interest with the addition of deeply branching members of these groups, as well as the placement of several incertae sedis taxa.
Methods. We sequenced 18 chloroplast genomes across Chlorophyceae to compile a data set of 58 protein-coding genes of a total of 68 chlorophycean taxa. We analyzed the concatenated nucleotide and amino acid datasets in the Bayesian and Maximum Likelihood frameworks, supplemented by analyses to examine potential discordant signal among genes. We also examined gene presence and absence data across Chlorophyceae.
Results. Concatenated analyses yielded at least two well-supported phylogenies: nucleotide data supported the traditional classification with the inclusion of the enigmatic Treubarinia into Sphaeropleales sensu lato. However, amino acid data yielded equally strong support for Sphaeropleaceae as sister to Volvocales, with the rest of the taxa traditionally classified in Sphaeropleales in a separate clade, and Treubarinia as sister to all of the above. Single-gene and other supplementary analyses indicated that the data have low phylogenetic signal at these critical nodes. Major clades were supported by genomic structural features such as gene losses and trans-spliced intron insertions in the plastome.
Discussion. While the sequence and gene order data support the deep split between the SV and OCC lineages, multiple phylogenetic hypotheses are possible for Sphaeropleales s.l. Given this uncertainty as well as the higher-taxonomic disorder seen in other algal groups, dwelling on well-defined, strongly supported Linnaean orders is not currently practical in Chlorophyceae and a less formal clade system may be more useful in the foreseeable future. For example, we identify two strongly and unequivocally supported clades: Treubarinia and Scenedesminia, as well as other smaller groups that could serve a practical purpose as named clades. This system does not preclude future establishment of new orders, or emendment of the current ordinal classification if new data support such conclusions
Order, Please! Uncertainty in the Ordinal-Level Classification of Chlorophyceae
Background. Chlorophyceae is one of three most species-rich green algal classes and also the only class in core Chlorophyta whose monophyly remains uncontested as gene and taxon sampling improves. However, some key relationships within Chlorophyceae are less clear-cut and warrant further investigation. The present study combined genome-scale chloroplast data and rich sampling in an attempt to resolve the ordinal classification in Chlorophyceae. The traditional division into Sphaeropleales and Volvocales (SV), and a clade containing Oedogoniales, Chaetopeltidales, and Chaetophorales (OCC) was of particular interest with the addition of deeply branching members of these groups, as well as the placement of several incertae sedis taxa.
Methods. We sequenced 18 chloroplast genomes across Chlorophyceae to compile a data set of 58 protein-coding genes of a total of 68 chlorophycean taxa. We analyzed the concatenated nucleotide and amino acid datasets in the Bayesian and Maximum Likelihood frameworks, supplemented by analyses to examine potential discordant signal among genes. We also examined gene presence and absence data across Chlorophyceae.
Results. Concatenated analyses yielded at least two well-supported phylogenies: nucleotide data supported the traditional classification with the inclusion of the enigmatic Treubarinia into Sphaeropleales sensu lato. However, amino acid data yielded equally strong support for Sphaeropleaceae as sister to Volvocales, with the rest of the taxa traditionally classified in Sphaeropleales in a separate clade, and Treubarinia as sister to all of the above. Single-gene and other supplementary analyses indicated that the data have low phylogenetic signal at these critical nodes. Major clades were supported by genomic structural features such as gene losses and trans-spliced intron insertions in the plastome.
Discussion. While the sequence and gene order data support the deep split between the SV and OCC lineages, multiple phylogenetic hypotheses are possible for Sphaeropleales s.l. Given this uncertainty as well as the higher-taxonomic disorder seen in other algal groups, dwelling on well-defined, strongly supported Linnaean orders is not currently practical in Chlorophyceae and a less formal clade system may be more useful in the foreseeable future. For example, we identify two strongly and unequivocally supported clades: Treubarinia and Scenedesminia, as well as other smaller groups that could serve a practical purpose as named clades. This system does not preclude future establishment of new orders, or emendment of the current ordinal classification if new data support such conclusions
Microlensing of Relativistic Knots in the Quasar HE1104-1805
We present 3 years of photometry of the ``Double Hamburger'' lensed quasar,
HE1104-1805, obtained on 102 separate nights using the OGLE 1.3-m telescope.
Both the A and B images show variations, but with substantial differences in
the lighcurves at all time delays. At the 310 day delay reported by Wisotzki
and collaborators the difference lightcurve has an rms amplitude of 0.060 mag.
The structure functions for the A and B images are quite different, with image
A more than twice as variable as image B (a factor of 4 in structure function)
on timescales of less than a month. Adopting microlensing as a working
hypothesis for the uncorrelated variability, the short timescale argues for the
relativistic motion of one or more components of the source. We argue that the
small amplitude of the fluctuations is due to the finite size of the source
with respect to the microlenses.Comment: As accepted for publication in ApJ. 22 pages. The discussion of
microlensing at high optical depth has been shortened and a few minor points
have been clarifie
Development and psychometric properties of the Carer – Head Injury Neurobehavioral Assessment Scale (C-HINAS) and the Carer – Head Injury Participation Scale (C-HIPS): patient and family determined outcome scales
Objective: Develop and assess the psychometric properties of the Carer - Head Injury Participation Scale (C-HIPS) and its biggest factor the Carer - Head Injury Neurobehavioral Assessment Scale (C-HINAS). Furthermore, the aim was to examine the inter-informant reliability by comparing the self reports of individuals with traumatic brain injury (TBI) with the carer reports on the C-HIPS and the C-HINAS. Method: Thirty-two TBI individuals and 27 carers took part in in-depth qualitative interviews exploring the consequences of the TBI. Interview transcripts were analysed and key themes and concepts were used to construct a 49-item and 58-item patient (Patient - Head Injury Participation Scale [P-HIPS]) and carer outcome measure (C-HIPS) respectively, of which 49 were parallel items and nine additional items were used to assess carer burden. Postal versions of the P-HIPS, C-HIPS, Mayo Portland Adaptability Inventory-3 (MPAI-3), and the Glasgow Outcome Scale-Extended (GOSE) were completed by a cohort of 113 TBI individuals and 80 carers. Data from a sub-group of 66 patient/carer pairs were used to compare inter-informant reliability between the P-HIPS and the C-HIPS, and the P-HINAS and the C-HINAS respectively. Results: All individual 49 items of the C-HIPS and their total score showed good test-retest reliability (0.95) and internal consistency (0.95). Comparisons with the MPAI-3 and GOSE found a good correlation with the MPAI-3 (0.7) and a moderate negative correlation with the GOSE (-0.6). Factor analysis of these items extracted a 4-factor structure which represented the domains 'Emotion/Behavior' (C-FUNAS),'Independence/ Community Living', 'Cognition', and 'Physical'. The C-HINAS showed good internal consistency (0.92), test-retest reliability (0.93), and concurrent validity with one MPAI subscale (0.7). Assessment of inter-informant reliability revealed good correspondence between the reports of the patients and the carers for both the C-HIPS (0.83) and the C-HINAS (0.82). Conclusion: Both the C-HINAS and the C-HIPS show strong psychometric properties. The qualitative methodology employed in the construction stage of the questionnaires provided good evidence of face and content validity. Comparisons between the P-HIPS and the C-HIPS, and the P-HINAS and the C-HINAS indicated high levels of agreement suggesting that in situations where the patient is unable to provide self-reports, information provided by the carer could be used. © 2007 Dove Medical Press Limited. All rights reserved
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