Product and other fine structure in polynomial resolutions of mapping spaces

Let Map_T(K,X) denote the mapping space of continuous based functions between two based spaces K and X. If K is a fixed finite complex, Greg Arone has recently given an explicit model for the Goodwillie tower of the functor sending a space X to the suspension spectrum \Sigma^\infty Map_T(K,X). Applying a generalized homology theory h_* to this tower yields a spectral sequence, and this will converge strongly to h_*(Map_T(K,X)) under suitable conditions, e.g. if h_* is connective and X is at least dim K connected. Even when the convergence is more problematic, it appears the spectral sequence can still shed considerable light on h_*(Map_T(K,X)). Similar comments hold when a cohomology theory is applied. In this paper we study how various important natural constructions on mapping spaces induce extra structure on the towers. This leads to useful interesting additional structure in the associated spectral sequences. For example, the diagonal on Map_T(K,X) induces a `diagonal' on the associated tower. After applying any cohomology theory with products h^*, the resulting spectral sequence is then a spectral sequence of differential graded algebras. The product on the E_\infty -term corresponds to the cup product in h^*(Map_T(K,X)) in the usual way, and the product on the E_1-term is described in terms of group theoretic transfers. We use explicit equivariant S-duality maps to show that, when K is the sphere S^n, our constructions at the fiber level have descriptions in terms of the Boardman-Vogt little n-cubes spaces. We are then able to identify, in a computationally useful way, the Goodwillie tower of the functor from spectra to spectra sending a spectrum X to \Sigma ^\infty \Omega ^\infty X.Comment: Published by Algebraic and Geometric Topology at http://www.maths.warwick.ac.uk/agt/AGTVol2/agt-2-28.abs.htm

Assimilation via Prices or Quantities? : Labor Market Institutions and Immigrant Earnings Growth in Australia, Canada and the United States

How do international differences in labor market institutions affect the nature of immigrant earnings assimilation? Using 1980/81 and 1990/91 cross-sections of census data from Australia, Canada, and the United States, we estimate the separate effects of arrival cohort and duration of destination-country residence on immigrant outcomes in each country. Relatively inflexible wages and generous unemployment insurance in Australia suggest that immigrants there might improve themselves primarily through employment gains rather than wage growth, and we find empirically that employment gains explain all of the labor market progress experienced by Australian immigrants. Wages are less rigid in Canada and the United States than in Australia, with the general consensus that the U.S. labor market is the most flexible of the three. We find that wage assimilation is an important source of immigrant earnings growth in both Canada and the United States, but the magnitude of wage assimilation is substantially larger in the United States. These same general patterns remain when we replicate our analyses for two subsamples of immigrants - Europeans and Asians - that are more homogeneous in national origins yet still provide sufficiently large sample sizes for each country

Assimilation via Prices or Quantities? Labor Market Institutions and Immigrant Earnings Growth in Australia, Canada, and the United States

How do international differences in labor market institutions affect the nature of immigrant earnings assimilation? Using 1980/81 and 1990/91 cross-sections of census data from Australia, Canada, and the United States, we estimate the separate effects of arrival cohort and duration of destination-country residence on immigrant outcomes in each country. Relatively inflexible wages and generous unemployment insurance in Australia suggest that immigrants there might improve themselves primarily through employment gains rather than wage growth, and we find empirically that employment gains explain all of the labor market progress experienced by Australian immigrants. Wages are less rigid in Canada and the United States than in Australia, with the general consensus that the U.S. labor market is the most flexible of the three. We find that wage assimilation is an important source of immigrant earnings growth in both Canada and the United States, but the magnitude of wage assimilation is substantially larger in the United States. These same general patterns remain when we replicate our analyses for two subsamples of immigrants – Europeans and Asians – that are more homogeneous in national origins yet still provide sufficiently large sample sizes for each country

Correcting Aberrations of a Transverse-Field Neutron Resonance Spin Echo Instrument

The neutron resonance spin echo (NRSE) technique has the potential to increase the Fourier time and energy resolution in neutron scattering by using radio-frequency (rf) neutron spin-flippers. However, aberrations arising from variations in the neutron path length between the rf flippers reduce the polarization. Here, we develop and test a transverse static-field magnet, a series of which are placed between the rf flippers, to correct for these aberrations. The prototype correction magnet was both simulated in an NRSE beamline using McStas, a Monte Carlo neutron ray-tracing software package, and measured using neutrons. The results from the prototype demonstrate that this static-field design corrects for transverse-field NRSE aberrations.Comment: 8 figures, 10 page

cis sequence effects on gene expression

<p>Abstract</p> <p>Background</p> <p>Sequence and transcriptional variability within and between individuals are typically studied independently. The joint analysis of sequence and gene expression variation (genetical genomics) provides insight into the role of linked sequence variation in the regulation of gene expression. We investigated the role of sequence variation in <it>cis </it>on gene expression (<it>cis </it>sequence effects) in a group of genes commonly studied in cancer research in lymphoblastoid cell lines. We estimated the proportion of genes exhibiting <it>cis </it>sequence effects and the proportion of gene expression variation explained by <it>cis </it>sequence effects using three different analytical approaches, and compared our results to the literature.</p> <p>Results</p> <p>We generated gene expression profiling data at N = 697 candidate genes from N = 30 lymphoblastoid cell lines for this study and used available candidate gene resequencing data at N = 552 candidate genes to identify N = 30 candidate genes with sufficient variance in both datasets for the investigation of <it>cis </it>sequence effects. We used two additive models and the haplotype phylogeny scanning approach of Templeton (Tree Scanning) to evaluate association between individual SNPs, all SNPs at a gene, and diplotypes, with log-transformed gene expression. SNPs and diplotypes at eight candidate genes exhibited statistically significant (p < 0.05) association with gene expression. Using the literature as a "gold standard" to compare 14 genes with data from both this study and the literature, we observed 80% and 85% concordance for genes exhibiting and not exhibiting significant <it>cis </it>sequence effects in our study, respectively.</p> <p>Conclusion</p> <p>Based on analysis of our results and the extant literature, one in four genes exhibits significant <it>cis </it>sequence effects, and for these genes, about 30% of gene expression variation is accounted for by <it>cis </it>sequence variation. Despite diverse experimental approaches, the presence or absence of significant <it>cis </it>sequence effects is largely supported by previously published studies.</p

A Longitudinal Seroepidemiology Study to Evaluate Antibody Response to SARS-COV-2 Virus Infection and Vaccination in Children in Calgary, Canada From July 2020 to April 2022: Alberta Covid-19 Childhood Cohort (AB3C) Study

BACKGROUND: Measurement of SARS-CoV-2 antibody seropositivity is important to accurately understand exposure to infection and/or vaccination in specific populations. This study aimed to estimate the serologic response to SARS-CoV-2 virus infection and vaccination in children in Calgary, Alberta over a two-year period. METHODS: Children with or without prior SARS-CoV-2 infections, were enrolled in Calgary, Canada in 2020. Venous blood was sampled 4 times from July 2020 to April 2022 for SARS-CoV-2 nucleocapsid and spike antibodies. Demographic and clinical information was obtained including SARS-CoV-2 testing results and vaccination records. RESULTS: 1035 children were enrolled and 88.9% completed all 4 visits; median age 9 years (IQR: 5,13); 519 (50.1%) female; and 815 (78.7%) Caucasian. Before enrolment, 118 (11.4%) had confirmed or probable SARS-CoV-2. By April 2022, 39.5% of previously uninfected participants had a SARS-CoV-2 infection. Nucleocapsid antibody seropositivity declined to 16.4% of all infected children after more than 200 days post diagnosis. Spike antibodies remained elevated in 93.6% of unvaccinated infected children after more than 200 days post diagnosis. By April 2022, 408 (95.6%) children 12 years and older had received 2 or more vaccine doses, and 241 (61.6%) 5 to 11 year-old children had received 2 vaccine doses. At that time, all 685 vaccinated children had spike antibodies, compared with 94/176 (53.4%) of unvaccinated children. CONCLUSIONS: In our population, after the first peak of Omicron variant infections and introduction of COVID-19 vaccines for children, all vaccinated children, but just over one-half of unvaccinated children, had SARS-CoV-2 spike antibodies indicating infection and/or vaccination, highlighting the benefit of vaccination. It is not yet known whether a high proportion of seropositivity at the present time predicts sustained population-level protection against future SARS-CoV-2 transmission, infection or severe COVID-19 outcomes in children