179 research outputs found
Do Children Who Move Home and School Frequently Have Poorer Educational Outcomes in Their Early Years at School? An Anonymised Cohort Study
Frequent mobility has been linked to poorer educational attainment. We investigated the association between moving
home and moving school frequently and the early childhood formal educational achievement. We carried out a cohort
analysis of 121,422 children with anonymised linked records. Our exposure measures were: 1) the number of residential
moves registered with a health care provider, and 2) number of school moves. Our outcome was the formal educational
assessment at age 6–7. Binary regression modeling was used to examine residential moves within the three time periods: 0
– ,1 year; 1 – ,4 years and 4 – ,6 years. School moves were examined from age 4 to age 6. We adjusted for demographics,
residential moves at different times, school moves and birth related variables. Children who moved home frequently were
more likely not to achieve in formal assessments compared with children not moving. Adjusted odds ratios were significant
for 3 or more moves within the time period 1 –,4 years and for any number of residential moves within the time period 4–
,6 years. There was a dose response relationship, with increased odds ratios with increased frequency of residential moves
(2 or more moves at 4–,6 years, adjusted odds ratio 1.16 (1.03, 1.29). The most marked effect was seen with frequent
school moves where 2 or more moves resulted in an adjusted odds ratio of 2.33 (1.82, 2.98). This is the first study to examine
the relationship between residential and school moves in early childhood and the effect on educational attainment.
Children experiencing frequent mobility may be disadvantaged and should be closely monitored. Additional educational
support services should be afforded to children, particularly those who frequently change school, in order to help them
achieve the expected educational standards
Search for the neutral Higgs bosons of the minimal supersymmetric standard model in pp collisions at root s=7 TeV with the ATLAS detector
A search for neutral Higgs bosons of the Minimal Supersymmetric Standard Model (MSSM) is reported. The analysis is based on a sample of proton-proton collisions at a centre-of-mass energy of 7TeV recorded with the ATLAS detector at the Large Hadron Collider. The data were recorded in 2011 and correspond to an integrated luminosity of 4.7 fb-1 to 4.8 fb-1. Higgs boson decays into oppositely-charged muon or τ lepton pairs are considered for final states requiring either the presence or absence of b-jets. No statistically significant excess over the expected background is observed and exclusion limits at the 95% confidence level are derived. The exclusion limits are for the production cross-section of a generic neutral Higgs boson, φ, as a function of the Higgs boson mass and for h/A/H production in the MSSM as a function of the parameters mA and tan β in the mhmax scenario for mA in the range of 90GeV to 500 GeV. Copyright CERN
Multifaceted Regulation of Translational Readthrough by RNA Replication Elements in a Tombusvirus
Translational readthrough of stop codons by ribosomes is a recoding event used by a variety of viruses, including plus-strand RNA tombusviruses. Translation of the viral RNA-dependent RNA polymerase (RdRp) in tombusviruses is mediated using this strategy and we have investigated this process using a variety of in vitro and in vivo approaches. Our results indicate that readthrough generating the RdRp requires a novel long-range RNA-RNA interaction, spanning a distance of ∼3.5 kb, which occurs between a large RNA stem-loop located 3'-proximal to the stop codon and an RNA replication structure termed RIV at the 3'-end of the viral genome. Interestingly, this long-distance RNA-RNA interaction is modulated by mutually-exclusive RNA structures in RIV that represent a type of RNA switch. Moreover, a different long-range RNA-RNA interaction that was previously shown to be necessary for viral RNA replicase assembly was also required for efficient readthrough production of the RdRp. Accordingly, multiple replication-associated RNA elements are involved in modulating the readthrough event in tombusviruses and we propose an integrated mechanistic model to describe how this regulatory network could be advantageous by (i) providing a quality control system for culling truncated viral genomes at an early stage in the replication process, (ii) mediating cis-preferential replication of viral genomes, and (iii) coordinating translational readthrough of the RdRp with viral genome replication. Based on comparative sequence analysis and experimental data, basic elements of this regulatory model extend to other members of Tombusviridae, as well as to viruses outside of this family
Estimates of new and total productivity in central Long Island Sound from in situ measurements of nitrate and dissolved oxygen
Author Posting. © The Author(s), 2013. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Estuaries and Coasts 36 (2013): 74-97, doi:10.1007/s12237-012-9560-5.Biogeochemical cycles in estuaries are regulated by a diverse set of physical and
biological variables that operate over a variety of time scales. Using in situ optical sensors, we
conducted a high-frequency time-series study of several biogeochemical parameters at a mooring
in central Long Island Sound from May to August 2010. During this period, we documented
well-defined diel cycles in nitrate concentration that were correlated to dissolved oxygen, wind
stress, tidal mixing, and irradiance. By filtering the data to separate the nitrate time series into
various signal components, we estimated the amount of variation that could be ascribed to each
process. Primary production and surface wind stress explained 59% and 19%, respectively, of the
variation in nitrate concentrations. Less frequent physical forcings, including large-magnitude wind events and spring tides, served to decouple the relationship between oxygen, nitrate, and
sunlight on about one-quarter of study days. Daytime nitrate minima and dissolved oxygen
maxima occurred nearly simultaneously on the majority (> 80%) of days during the study period;
both were strongly correlated with the daily peak in irradiance. Nighttime nitrate maxima
reflected a pattern in which surface-layer stocks were depleted each afternoon and recharged the
following night. Changes in nitrate concentrations were used to generate daily estimates of new
primary production (182 ± 37 mg C m-2 d-1) and the f-ratio (0.25), i.e., the ratio of production
based on nitrate to total production. These estimates, the first of their kind in Long Island Sound,
were compared to values of community respiration, primary productivity, and net ecosystem
metabolism, which were derived from in situ measurements of oxygen concentration. Daily
averages of the three metabolic parameters were 1660 ± 431, 2080 ± 419, and 429 ± 203 mg C
m-2 d-1, respectively. While the system remained weakly autotrophic over the duration of the
study period, we observed very large day-to-day differences in the f-ratio and in the various
metabolic parameters.This work was supported by the Yale
Institute for Biospheric Studies, the Sounds Conservancy of the Quebec-Labrador Foundation,
and the Yale School of Forestry and Environmental Studies Carpenter-Sperry Fund.2014-01-0
Differential responses of needle and branch order-based root decay to nitrogen addition: dominant effects of acid-unhydrolyzable residue and microbial enzymes
Increased Membrane Cholesterol in Lymphocytes Diverts T-Cells toward an Inflammatory Response
Cell signaling for T-cell growth, differentiation, and apoptosis is initiated in the cholesterol-rich microdomains of the plasma membrane known as lipid rafts. Herein, we investigated whether enrichment of membrane cholesterol in lipid rafts affects antigen-specific CD4 T-helper cell functions. Enrichment of membrane cholesterol by 40–50% following squalene administration in mice was paralleled by an increased number of resting CD4 T helper cells in periphery. We also observed sensitization of the Th1 differentiation machinery through co-localization of IL-2Rα, IL-4Rα, and IL-12Rβ2 subunits with GM1 positive lipid rafts, and increased STAT-4 and STAT-5 phosphorylation following membrane cholesterol enrichment. Antigen stimulation or CD3/CD28 polyclonal stimulation of membrane cholesterol-enriched, resting CD4 T-cells followed a path of Th1 differentiation, which was more vigorous in the presence of increased IL-12 secretion by APCs enriched in membrane cholesterol. Enrichment of membrane cholesterol in antigen-specific, autoimmune Th1 cells fostered their organ-specific reactivity, as confirmed in an autoimmune mouse model for diabetes. However, membrane cholesterol enrichment in CD4+
Foxp3+ T-reg cells did not alter their suppressogenic function. These findings revealed a differential regulatory effect of membrane cholesterol on the function of CD4 T-cell subsets. This first suggests that membrane cholesterol could be a new therapeutic target to modulate the immune functions, and second that increased membrane cholesterol in various physiopathological conditions may bias the immune system toward an inflammatory Th1 type response
Cheek Tooth Morphology and Ancient Mitochondrial DNA of Late Pleistocene Horses from the Western Interior of North America: Implications for the Taxonomy of North American Late Pleistocene Equus
Horses were a dominant component of North American Pleistocene land mammal communities and their remains are well represented in the fossil record. Despite the abundant material available for study, there is still considerable disagreement over the number of species of Equus that inhabited the different regions of the continent and on their taxonomic nomenclature. In this study, we investigated cheek tooth morphology and ancient mtDNA of late Pleistocene Equus specimens from the Western Interior of North America, with the objective of clarifying the species that lived in this region prior to the end-Pleistocene extinction. Based on the morphological and molecular data analyzed, a caballine (Equus ferus) and a non-caballine (E. conversidens) species were identified from different localities across most of the Western Interior. A second non-caballine species (E. cedralensis) was recognized from southern localities based exclusively on the morphological analyses of the cheek teeth. Notably the separation into caballine and non-caballine species was observed in the Bayesian phylogenetic analysis of ancient mtDNA as well as in the geometric morphometric analyses of the upper and lower premolars. Teeth morphologically identified as E. conversidens that yielded ancient mtDNA fall within the New World stilt-legged clade recognized in previous studies and this is the name we apply to this group. Geographic variation in morphology in the caballine species is indicated by statistically different occlusal enamel patterns in the specimens from Bluefish Caves, Yukon Territory, relative to the specimens from the other geographic regions. Whether this represents ecomorphological variation and/or a certain degree of geographic and genetic isolation of these Arctic populations requires further study
What Happened to Gray Whales during the Pleistocene? The Ecological Impact of Sea-Level Change on Benthic Feeding Areas in the North Pacific Ocean
Gray whales (Eschrichtius robustus) undertake long migrations, from Baja California to Alaska, to feed on seasonally productive benthos of the Bering and Chukchi seas. The invertebrates that form their primary prey are restricted to shallow water environments, but global sea-level changes during the Pleistocene eliminated or reduced this critical habitat multiple times. Because the fossil record of gray whales is coincident with the onset of Northern Hemisphere glaciation, gray whales survived these massive changes to their feeding habitat, but it is unclear how.We reconstructed gray whale carrying capacity fluctuations during the past 120,000 years by quantifying gray whale feeding habitat availability using bathymetric data for the North Pacific Ocean, constrained by their maximum diving depth. We calculated carrying capacity based on modern estimates of metabolic demand, prey availability, and feeding duration; we also constrained our estimates to reflect current population size and account for glaciated and non-glaciated areas in the North Pacific. Our results show that key feeding areas eliminated by sea-level lowstands were not replaced by commensurate areas. Our reconstructions show that such reductions affected carrying capacity, and harmonic means of these fluctuations do not differ dramatically from genetic estimates of carrying capacity.Assuming current carrying capacity estimates, Pleistocene glacial maxima may have created multiple, weak genetic bottlenecks, although the current temporal resolution of genetic datasets does not test for such signals. Our results do not, however, falsify molecular estimates of pre-whaling population size because those abundances would have been sufficient to survive the loss of major benthic feeding areas (i.e., the majority of the Bering Shelf) during glacial maxima. We propose that gray whales survived the disappearance of their primary feeding ground by employing generalist filter-feeding modes, similar to the resident gray whales found between northern Washington State and Vancouver Island
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Search for neutral MSSM Higgs bosons decaying to a pair of tau leptons in pp collisions
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