Invariant manifolds and the geometry of front propagation in fluid flows

Recent theoretical and experimental work has demonstrated the existence of one-sided, invariant barriers to the propagation of reaction-diffusion fronts in quasi-two-dimensional periodically-driven fluid flows. These barriers were called burning invariant manifolds (BIMs). We provide a detailed theoretical analysis of BIMs, providing criteria for their existence, a classification of their stability, a formalization of their barrier property, and mechanisms by which the barriers can be circumvented. This analysis assumes the sharp front limit and negligible feedback of the front on the fluid velocity. A low-dimensional dynamical systems analysis provides the core of our results.Comment: 14 pages, 11 figures. To appear in Chaos Focus Issue: Chemo-Hydrodynamic Patterns and Instabilities (2012

Detection of the old stellar component of the major Galactic bar

We present near-IR colour--magnitude diagrams and star counts for a number of regions along the Galactic plane. It is shown that along the l=27 b=0 line of sight there is a feature at 5.7 +-0.7kpc with a density of stars at least a factor two and probably more than a factor five times that of the disc at the same position. This feature forms a distinct clump on an H vs. J-H diagram and is seen at all longitudes from the bulge to about l=28, but at no longitude greater than this. The distance to the feature at l=20 is about 0.5kpc further than at l=27 and by l=10 it has merged with, or has become, the bulge. Given that at l=27 and l=21 there is also a clustering of very young stars, the only component that can reasonably explain what is seen is a bar with half length of around 4kpc and a position angle of about 43+-7.Comment: 5 pages, 5 figures accepted as a letter in MNRA

Relationship between occurrence of Guillain-Barre syndrome and mass campaign of measles and rubella immunization in Iranian 5-14 years old children

Background: Case reports and epidemiologic studies have reported a relation between different vaccines including measles, rubella, mumps and Guillain-Barre syndrome (GBS). In this study we investigated relation between receiving measles and/or rubella vaccines and occurrence of GBS after national immunization campaign in 2003 in Iran. Materials and methods: We used the national surveillance system for acute flaccid paralysis from the beginning of 2002 to the end of 2004 and studied the incidence of GBS disease among 5-14-year-old children. The 3-year time span of the study was divided into fifteen 10 weeks intervals and the number of reported and confirmed GBS case reports in each time period was analyzed supposing their distribution was according to Poisson distribution. Results: From 2002 through 2004 there were 370 patients confirmed GBS case reports among persons 5-14 years of age. The annual incidence in this age group remained relatively constant over the 3-year period and ranged from 0.65 per 100,000 population in 2004 to 0.76 in 2003. The estimated average annual incidence of GBS in persons <15 years of age was 1/100,000 (CI 95%: 0.88-1.13), and 0.7/100,000 in persons 5-14 years of age (CI 95%: 0.58-0.83). No obvious seasonal pattern in GBS occurrence was observed. The mean number of GBS patients during each 10 week study interval was 23.8. Twenty-five patients with GBS were reported in the time period which coincided with national immunization campaign. The probability of occurring ≥25 cases of GBS in that time period according to Poison distribution with expected case numbers of 23-8 is equal to 0.43 (p = 0.43). Conclusion: The yearly incidence rate of GBS in this study was similar to other studies. According to our results, there was no increase in GBS Incidence in the 4 weeks national Immunization campaign and 6 weeks after it in comparison to other 10 weeks periods before or after this time period. © 2008 Elsevier Ltd. All rights reserved

A High-Density Linkage Map of the Ancestral Diploid Strawberry, Fragaria iinumae, Constructed with Single Nucleotide Polymorphism Markers from the IStraw90 Array and Genotyping by Sequencing

Fragaria iinumae Makino is recognized as an ancestor of the octoploid strawberry species, which includes the cultivated strawberry, Fragaria ×ananassa Duchesne ex Rozier. Here we report the construction of the first high-density linkage map for F. iinumae. The F. iinumae linkage map (Fii map) is based on two high-throughput techniques of single nucleotide polymorphism (SNP) genotyping: the IStraw90 Array (hereafter “Array”), and genotyping by sequencing (GBS). The F2 generation mapping population was derived by selfing F. iinumae hybrid F1D, the product of a cross between two divergent F. iinumae accessions collected from Hokkaido, Japan. The Fii map consists of seven linkage groups (LGs) and has an overall length of 451.7 cM as defined by 496 loci populated by 4173 markers: 3280 from the Array and 893 from GBS. Comparisons with two versions of the Fragaria vesca ssp. vesca L. ‘Hawaii 4’ pseudo-chromosome (PC) assemblies reveal substantial conservation of synteny and colinearity, yet identified differences that point to possible genomic divergences between F. iinumae and F. vesca, and/or to F. vesca genomic assembly errors. The Fii map provides a basis for anchoring a F. iinumae genome assembly as a prerequisite for constructing a second diploid reference genome for Fragaria

Ambiguity, multiple streams, and EU policy

The multiple streams framework draws insight from interactions between agency and institutions to explore the impact of context, time, and meaning on policy change and to assess the institutional and issue complexities permeating the European Union (EU) policy process. The authors specify the assumptions and structure of the framework and review studies that have adapted it to reflect more fully EU decision-making processes. The nature of policy entrepreneurship and policy windows are assessed to identify areas of improvement. Finally, the authors sketch out a research agenda that refines the logic of political manipulation which permeates the lens and the institutional complexity which frames the EU policy process

Associations of dry skin, skin care habits, well‐being, sleep quality and itch in nursing home residents : results of a multicentre, observational, cross‐sectional study

Aim: Dry skin is one of the most frequent cutaneous problems in aged long-term care residents. Although it is clinically relevant, the impact on quality of life is unclear. The objective was to measure well-being, sleep quality and itch in nursing home residents being 65 years and older and to explore possible associations with demographics, dry skin and skincare habits. Design: Multicentre, observational, cross-sectional. Methods: Sleep quality was assessed with the Richards-Campbell Sleep Quality Questionnaire, well-being with the WHO-Five Well-being Index and itch with the 5-D Itch scale. Skin dryness was measured using the Overall Dry Skin score. Results: A total of 51 residents were included. The item scores of the sleep quality and itch questionnaires were strongly associated with each other. Demographics, dry skin and skincare habits were not associated with the questionnaires. It is unclear whether basic skincare activities can improve the quality of life in this population

A major star formation region in the receding tip of the stellar Galactic bar

We present an analysis of the optical spectroscopy of 58 stars in the Galactic plane at $l=27$\arcdeg, where a prominent excess in the flux distribution and star counts have been observed in several spectral regions, in particular in the Two Micron Galactic Survey (TMGS) catalog. The sources were selected from the TMGS, to have a $K$ magnitude brighter than +5 mag and be within 2 degrees of the Galactic plane. More than 60% of the spectra correspond to stars of luminosity class I, and a significant proportion of the remainder are very late giants which would also be fast evolving. This very high concentration of young sources points to the existence of a major star formation region in the Galactic plane, located just inside the assumed origin of the Scutum spiral arm. Such regions can form due to the concentrations of shocked gas where a galactic bar meets a spiral arm, as is observed at the ends of the bars of face-on external galaxies. Thus, the presence of a massive star formation region is very strong supporting evidence for the presence of a bar in our Galaxy.Comment: 13 pages (latex) + 4 figures (eps), accepted in ApJ Let

Radiation Effects in CdZnTe Gamma-Ray Detectors Produced by 199 MeV Protons

Many future space missions will use cadmium zinc telluride (CdZnTe) gamma-ray detectors because their operation at room temperature makes compact, lightweight detector systems possible. Even though instruments for space using CdZnTe detectors have already been built, the effect of the high- energy particle space environment on these detectors has not been measured. To determine the effect of energetic charged particles on these detectors, we have bombarded several CdZnTe detectors with 199 MeV protons at the Indiana University Cyclotron Facility. Planar detectors of area 1 cm^2 and thickness 2-3 mm from both eV products and Digirad were irradiated, along with a 2 multiplied by 2 array of proprietary design from Digirad. Using standard gamma-ray sources, the response of the detectors was measured before and after bombardment in steps up to fluences of 5 multiplied by 10^9 p cm^(-2). Significant effects from the proton irradiation were observed in the gamma-ray spectra. In particular, the peak positions of the lines in the spectrum were shifted downward proportional to the fluence. The explanation is almost certainly the production of electron traps by the high energy proton interactions, resulting in a decrease of the mobility-lifetime (µτ) ) product of the electrons. Calculations were made to model the effect of a decrease in electron trapping length on the spectrum

A major star formation region in the receding tip of the stellar Galactic bar. II. Supplementary information and evidence that the bar is not the same structure as the triaxial bulge previouly reported

This paper is the second part of Garzon et al. (1997: ApJ 491, L31) in which we presented an outline of the analysis of 60 spectra from a follow-up program to the Two Micron Galactic Survey (TMGS) project in the l=27 deg., b=0 deg. area. In this second part, we present a more detailed explanation of the analysis as well a library of the spectra for more complete information for each of the 60 stars, and further discussions on the implications for the structure of the Galaxy. This region contains a prominent excess in the flux distribution and star counts previously observed in several spectral ranges, notably in the TMGS. More than 50% of the spectra of the stars detected with m_K<5.0 mag, within a very high confidence level, correspond to stars of luminosity class I, and a significant proportion of the remainder are very late giants which must also be rapidly evolving. We make the case, using all the available evidence, that we are observing a region at the nearer end of the Galactic bar, where the Scutum spiral arm breaks away, and that this is powerful evidence for the presence of the bar. Alternative explanations do not give nearly such a satisfactory account of the observations. The space localization of one and, a fortiori, of both ends of the bar allows us to infer a position angle for the bar of around 75 deg. with respect to the Sun-Galactic centre line. The angle is different from that given by other authors for the bar and this, we think, is because they refer to the triaxial bulge and not to the bar as detected here.Comment: 21 pages, 1 table, 9 figures, accepted in A