Slow equivariant lump dynamics on the two sphere

The low-energy, rotationally equivariant dynamics of n CP^1 lumps on S^2 is studied within the approximation of geodesic motion in the moduli space of static solutions. The volume and curvature properties of this moduli space are computed. By lifting the geodesic flow to the completion of an n-fold cover of the moduli space, a good understanding of nearly singular lump dynamics within this approximation is obtained.Comment: 12 pages, 3 figure

Disturbance and Predictability of Flowering Patterns in Bird-Pollinated Cloud Forest Plants

The distribution and flowering patterns of hummingbird—pollinated plants were compared from July 1981 to June 1983 in three patch types in cloud forest at Monteverde, Costa Rica. Study plots were: (1) four recent, large (1100—2500 m2) disturbances ("cutovers") produced by cutting vegetation, (2) six recent, smaller (200—600 m2) disturbances caused by treefalls, and (3) four plots (1600—1800 m2) of canopied forest. Based on published literature dealing with communities that characterize different regimes of disturbance, we tested one assumption and two hypotheses. Assumption: Plant species composition differs among the three patch types. Hypothesis 1: Phenotypic specialization by plants for co—evolved interactions with hummingbirds will be lowest in large gaps, highest in forest, and intermediate in treefalls. Hypothesis 2: Predictability of flowering phenologies and nectar production will be lowest in large gaps, highest in forest, intermediate in treefalls. Neither the assumption nor the hypotheses were supported by the results. The patch mosaic in this cloud forest was not associated with major differences in species composition of bird—pollinated plants. Most species studied were self—compatible. Most abundant in cutovers were species with long corollas, relatively specialized for attracting long—billed hummingbirds. Species with short corollas, which can be visited by many hummingbird species and some insects, were most abundant in treefalls and forest. Variation in phenological patterns showed no consistent trends among patch types. Predictability of flower and nectar production tended to be greatest in treefalls, which are foci of concentrated flowering activity by all species. Discrepancies between our results and previous studies can be ascribed to two facts. (1) Much of the literature dealing with ecological consequences of disturbance has dealt with large—scale anthropogenic disturbances such as old fields of the eastern USA, whereas we studied small, natural, or quasi—natural disturbances. (2) Studies of forest disturbance have focused on the tree layer, whereas we studied the understory herbs, shrubs, and epiphytes. Natural disturbance usually involves death and replacement of one or more trees, whereas individuals of other life forms may persist through the disturbance

Reduced coronary flow reserve in Anderson-Fabry disease measured by transthoracic Doppler echocardiography

Coronary flow reserve was assessed in a patient with Anderson-Fabry disease complicated by symmetric left ventricular hypertrophy. Coronary flow reserve was measurable in all three major coronary arteries providing an opportunity to compare regional coronary flow reserve from different vascular beds. In this patient all the three vascular beds supplied diffusely hypertrophied myocardium. Coronary flow disturbances in small intramyocardial perforating arteries were visible. The coronary flow reserve was reduced to a similar level (around to 2.0) in all three major arteries. In our patient with Anderson-Fabry disease, the coronary vasodilatation was blunted in a diffuse pattern corresponding to the myocardial hypertrophy distribution. In small intramyocardial arteries coronary flow was also disturbed. Accordingly, retrograde systolic flow and accelerated anterograde diastolic flow were documented

Expected Performance of the ATLAS Experiment - Detector, Trigger and Physics

A detailed study is presented of the expected performance of the ATLAS detector. The reconstruction of tracks, leptons, photons, missing energy and jets is investigated, together with the performance of b-tagging and the trigger. The physics potential for a variety of interesting physics processes, within the Standard Model and beyond, is examined. The study comprises a series of notes based on simulations of the detector and physics processes, with particular emphasis given to the data expected from the first years of operation of the LHC at CERN

The current role of next-generation DNA sequencing in routine care of patients with hereditary cardiovascular conditions: a viewpoint paper of the European Society of Cardiology working group on myocardial and pericardial diseases and members of the European Society of Human Genetics

Cardiomyopathies, arrhythmic syndromes, aortopathies, and other cardiovascular diseases with Mendelian inheritance are relatively frequent conditions for which genetic testing is recommended in various guidelines.1,2 The most widely recognized indication for genetic testing in patients with these conditions is to identify a causative mutation and subsequently provide pre-symptomatic or predictive testing of relatives who are at risk of developing the same disease at a later stage. This process of cascade screening of family members ensures adequate clinical surveillance of mutation carriers and allows non-carriers to be discharged from clinical follow-up. A number of studies have reported a greater cost-effectiveness combining molecular screening with clinical screening compared with isolated clinical investigations.3 Previously, genetic testing was based on conventional techniques like Sanger sequencing analysing genes one by one, but recent advances in DNA sequencing technologies have made it possible to investigate large numbers of disease genes simultaneously, making mutation analysis much faster and cheaper. These new methods are known as next-generation sequencing (NGS) and represent a major advance in the ability to identify causative mutations in families affected by genetic diseases (see Supplementary material online, Figure S1).4,5 However, analysis of large numbers of genes may identify a number of sequence variants of uncertain clinical significance (VUS). As a result, cardiologists and clinical geneticists who counsel and manage families with inherited cardiovascular disorders are facing a major challenge in determining the clinical relevance of NGS results.6,7 This paper gives a brief overview of the principles of NGS, discusses the general strategies for the interpretation of sequencing results, and reviews the implications of NGS for cardio-genetic services. In addition, issues related to genetic counselling and ethical considerations are discussed. A summary of viewpoints is given in Table 1

Cross species comparison of C/EBPα and PPARγ profiles in mouse and human adipocytes reveals interdependent retention of binding sites

<p>Abstract</p> <p>Background</p> <p>The transcription factors peroxisome proliferator activated receptor γ (PPARγ) and CCAAT/enhancer binding protein α (C/EBPα) are key transcriptional regulators of adipocyte differentiation and function. We and others have previously shown that binding sites of these two transcription factors show a high degree of overlap and are associated with the majority of genes upregulated during differentiation of murine 3T3-L1 adipocytes.</p> <p>Results</p> <p>Here we have mapped all binding sites of C/EBPα and PPARγ in human SGBS adipocytes and compared these with the genome-wide profiles from mouse adipocytes to systematically investigate what biological features correlate with retention of sites in orthologous regions between mouse and human. Despite a limited interspecies retention of binding sites, several biological features make sites more likely to be retained. First, co-binding of PPARγ and C/EBPα in mouse is the most powerful predictor of retention of the corresponding binding sites in human. Second, vicinity to genes highly upregulated during adipogenesis significantly increases retention. Third, the presence of C/EBPα consensus sites correlate with retention of both factors, indicating that C/EBPα facilitates recruitment of PPARγ. Fourth, retention correlates with overall sequence conservation within the binding regions independent of C/EBPα and PPARγ sequence patterns, indicating that other transcription factors work cooperatively with these two key transcription factors.</p> <p>Conclusions</p> <p>This study provides a comprehensive and systematic analysis of what biological features impact on retention of binding sites between human and mouse. Specifically, we show that the binding of C/EBPα and PPARγ in adipocytes have evolved in a highly interdependent manner, indicating a significant cooperativity between these two transcription factors.</p

A Meta-Analysis of Local Adaptation in Plants

Local adaptation is of fundamental importance in evolutionary, population, conservation, and global-change biology. The generality of local adaptation in plants and whether and how it is influenced by specific species, population and habitat characteristics have, however, not been quantitatively reviewed. Therefore, we examined published data on the outcomes of reciprocal transplant experiments using two approaches. We conducted a meta-analysis to compare the performance of local and foreign plants at all transplant sites. In addition, we analysed frequencies of pairs of plant origin to examine whether local plants perform better than foreign plants at both compared transplant sites. In both approaches, we also examined the effects of population size, and of the habitat and species characteristics that are predicted to affect local adaptation. We show that, overall, local plants performed significantly better than foreign plants at their site of origin: this was found to be the case in 71.0% of the studied sites. However, local plants performed better than foreign plants at both sites of a pair-wise comparison (strict definition of local adaption) only in 45.3% of the 1032 compared population pairs. Furthermore, we found local adaptation much more common for large plant populations (>1000 flowering individuals) than for small populations (<1000 flowering individuals) for which local adaptation was very rare. The degree of local adaptation was independent of plant life history, spatial or temporal habitat heterogeneity, and geographic scale. Our results suggest that local adaptation is less common in plant populations than generally assumed. Moreover, our findings reinforce the fundamental importance of population size for evolutionary theory. The clear role of population size for the ability to evolve local adaptation raises considerable doubt on the ability of small plant populations to cope with changing environments