Using the Parkes radio telescope, we study the 21 cm neutral hydrogen (H i) properties of a sample of galaxies with redshifts z < 0.13 extracted from the optical Two-Degree-Field Galaxy Redshift ...Survey (2dFGRS). Galaxies at 0.04 < z < 0.13 are studied using new Parkes observations of a 42 deg2 field near the South Galactic Pole (SGP). A spectral stacking analysis of the 3277 2dFGRS objects within this field results in a convincing 12σ detection. For the low-redshift sample at 0 < z < 0.04, we use the 15 093 2dFGRS galaxies observed by the H i Parkes All-Sky Survey (HIPASS) and find a 31σ stacked detection. We measure average H i masses of (6.93 ± 0.17) × 109 and (1.48 ± 0.03) × 109 h
−2 M for the SGP and HIPASS samples, respectively. Accounting for source confusion and sample bias, we find a cosmic H i mass density of ΩHI
= (3.19−0.59
+0.43) × 10−4 h−1 for the SGP sample and (2.82−0.59
+0.30) × 10−4 h−1 for the HIPASS sample. This suggests no (12 ± 23 per cent) evolution in the cosmic H i density over the last ∼1 h
−1 Gyr. Due to the very large effective volumes, cosmic variance in our determination of ΩHI
is considerably lower than previous estimates. Our stacking analysis reproduces and quantifies the expected trends in the H i mass and mass-to-light ratio of galaxies with redshift, luminosity and colour.
This dataset provides growth form classifications for 67,413 vascular plant species from North, Central, and South America. The data used to determine growth form were compiled from five major ...integrated sources and two original publications: the Botanical Information and Ecology Network (BIEN), the Plant Trait Database (TRY), the SALVIAS database, the USDA PLANTS database, Missouri Botanical Garden's Tropicos database, Wright (2010), and Boyle (1996). We defined nine plant growth forms based on woodiness (woody or non-woody), shoot structure (self-supporting or not self-supporting), and root traits (rooted in soil, not rooted in soil, parasitic or aquatic): Epiphyte, Liana, Vine, Herb, Shrub, Tree, Parasite, or Aquatic. Species with multiple growth form classifications were assigned the growth form classification agreed upon by the majority (>2/3) of sources. Species with ambiguous or otherwise not interpretable growth form assignments were excluded from the final dataset but are made available with the original data. Comparisons with independent estimates of species richness for the Western hemisphere suggest that our final dataset includes the majority of New World vascular plant species. Coverage is likely more complete for temperate than for tropical species. In addition, aquatic species are likely under-represented. Nonetheless, this dataset represents the largest compilation of plant growth forms published to date, and should contribute to new insights across a broad range of research in systematics, ecology, biogeography, conservation, and global change science.
To cite this article: Boyle RJ, Ismail IH, Kivivuori S, Licciardi PV, Robins-Browne RM, Mah L-J, Axelrad C, Moore S, Donath S, Carlin JB, Lahtinen SJ, Tang MLK. Lactobacillus GG treatment during ...pregnancy for the prevention of eczema: a randomized controlled trial. Allergy 2011; 66: 509-516. ABSTRACT: Background: Probiotic supplementation in early life may be effective for preventing eczema. Previous studies have suggested that prenatal administration may be particularly important for beneficial effects. Objective: We examined whether prenatal treatment with the probiotic Lactobacillus rhamnosus GG (LGG) can influence the risk of eczema during infancy. Methods: We recruited 250 pregnant women carrying infants at high risk of allergic disease to a randomized controlled trial of probiotic supplementation (LGG 1.8 × 10¹⁰ cfu/day) from 36 weeks gestation until delivery. Infants were assessed during their first year for eczema or allergic sensitization. Immunological investigations were performed in a subgroup. Umbilical cord blood was examined for dendritic cell and regulatory T cell numbers and production of TGFβ, IL-10, IL-12, IL-13, IFN-γ and TNFα. Maternal breast milk was examined for total IgA, soluble CD14 and TGFβ. Results: Prenatal probiotic treatment was not associated with reduced risk of eczema (34% probiotic, 39% placebo; RR 0.88; 95% CI 0.63, 1.22) or IgE-associated eczema (18% probiotic, 19% placebo; RR 0.94; 95% CI 0.53, 1.68). Prenatal probiotic treatment was not associated with any change in cord blood immune markers, but was associated with decreased breast milk soluble CD14 and IgA levels. Conclusions: Prenatal treatment with Lactobacillus rhamnosus GG was not sufficient for preventing eczema. If probiotics are effective for preventing eczema, then a postnatal component to treatment or possibly an alternative probiotic strain is necessary.
Autism spectrum disorder (ASD) has a strong but complex genetic component. Here we report on the resequencing of 64 candidate neurodevelopmental disorder risk genes in 5,979 individuals: 3,486 ...probands and 2,493 unaffected siblings. We find a strong burden of de novo point mutations for these genes and specifically implicate nine genes. These include CHD2 and SYNGAP1, genes previously reported in related disorders, and novel genes TRIP12 and PAX5. We also show that mutation carriers generally have lower IQs and enrichment for seizures. These data begin to distinguish genetically distinct subtypes of autism important for aetiological classification and future therapeutics.
Fast radio bursts (FRBs) are brief, bright, extragalactic radio flashes
. Their physical origin remains unknown, but dozens of possible models have been postulated
. Some FRB sources exhibit repeat ...bursts
. Although over a hundred FRB sources have been discovered
, only four have been localized and associated with a host galaxy
, and just one of these four is known to emit repeating FRBs
. The properties of the host galaxies, and the local environments of FRBs, could provide important clues about their physical origins. The first known repeating FRB, however, was localized to a low-metallicity, irregular dwarf galaxy, and the apparently non-repeating sources were localized to higher-metallicity, massive elliptical or star-forming galaxies, suggesting that perhaps the repeating and apparently non-repeating sources could have distinct physical origins. Here we report the precise localization of a second repeating FRB source
, FRB 180916.J0158+65, to a star-forming region in a nearby (redshift 0.0337 ± 0.0002) massive spiral galaxy, whose properties and proximity distinguish it from all known hosts. The lack of both a comparably luminous persistent radio counterpart and a high Faraday rotation measure
further distinguish the local environment of FRB 180916.J0158+65 from that of the single previously localized repeating FRB source, FRB 121102. This suggests that repeating FRBs may have a wide range of luminosities, and originate from diverse host galaxies and local environments.
BackgroundJoubert syndrome (JS) is a recessive neurodevelopmental disorder characterised by hypotonia, ataxia, cognitive impairment, abnormal eye movements, respiratory control disturbances and a ...distinctive mid-hindbrain malformation. JS demonstrates substantial phenotypic variability and genetic heterogeneity. This study provides a comprehensive view of the current genetic basis, phenotypic range and gene–phenotype associations in JS.MethodsWe sequenced 27 JS-associated genes in 440 affected individuals (375 families) from a cohort of 532 individuals (440 families) with JS, using molecular inversion probe-based targeted capture and next-generation sequencing. Variant pathogenicity was defined using the Combined Annotation Dependent Depletion algorithm with an optimised score cut-off.ResultsWe identified presumed causal variants in 62% of pedigrees, including the first B9D2 mutations associated with JS. 253 different mutations in 23 genes highlight the extreme genetic heterogeneity of JS. Phenotypic analysis revealed that only 34% of individuals have a ‘pure JS’ phenotype. Retinal disease is present in 30% of individuals, renal disease in 25%, coloboma in 17%, polydactyly in 15%, liver fibrosis in 14% and encephalocele in 8%. Loss of CEP290 function is associated with retinal dystrophy, while loss of TMEM67 function is associated with liver fibrosis and coloboma, but we observe no clear-cut distinction between JS subtypes.ConclusionsThis work illustrates how combining advanced sequencing techniques with phenotypic data addresses extreme genetic heterogeneity to provide diagnostic and carrier testing, guide medical monitoring for progressive complications, facilitate interpretation of genome-wide sequencing results in individuals with a variety of phenotypes and enable gene-specific treatments in the future.
Abstract
We present the final catalogue of the 2dF QSO Redshift Survey (2QZ), based on Anglo-Australian Telescope 2dF spectroscopic observations of 44 576 colour-selected (ub
J
r) objects with 18.25 ...< b
J < 20.85 selected from automated plate measurement scans of UK Schmidt Telescope (UKST) photographic plates. The 2QZ comprises 23 338 quasi-stellar objects (QSOs), 12 292 galactic stars (including 2071 white dwarfs) and 4558 compact narrow emission-line galaxies. We obtained a reliable spectroscopic identification for 86 per cent of objects observed with 2dF. We also report on the 6dF QSO Redshift Survey (6QZ), based on UKST 6dF observations of 1564 brighter(16 < b
J < 18.25) sources selected from the same photographic input catalogue. In total, we identified 322 QSOs spectroscopically in the 6QZ. The completed 2QZ is, by more than a factor of 50, the largest homogeneous QSO catalogue ever constructed at these faint limits (b
J < 20.85) and high QSO surface densities (35 QSOs deg−2). As such, it represents an important resource in the study of the Universe at moderate-to-high redshifts. As an example of the results possible with the 2QZ, we also present our most recent analysis of the optical QSO luminosity function and its cosmological evolution with redshift. For a flat, Ωm= 0.3 and ΩΛ= 0.7, universe, we find that a double power law with luminosity evolution that is exponential in look-back time, τ, of the form L
*(z)∝ e6.15τ, equivalent to an e-folding time of 2 Gyr, provides an acceptable fit to the redshift dependence of the QSO LF over the range 0.4 < z < 2.1 and M
< −22.5. Evolution described by a quadratic in redshift is also an acceptable fit, with L
*(z)∝ 10.
Significance We present a conceptual framework for testing theories for the latitudinal gradient of species richness in terms of variation in functional diversity at the alpha, beta, and gamma ...scales. We compared ecological community theory with large-scale observational data of tree species richness and functional diversity. We found that the patterns of functional trait diversity are not consistent with any one theory of species diversity. These conflicting results indicate that none of the broad classes of biodiversity theory considered here is alone able to explain the latitudinal gradient of species diversity in terms of functional trait space.
The processes causing the latitudinal gradient in species richness remain elusive. Ecological theories for the origin of biodiversity gradients, such as competitive exclusion, neutral dynamics, and environmental filtering, make predictions for how functional diversity should vary at the alpha (within local assemblages), beta (among assemblages), and gamma (regional pool) scales. We test these predictions by quantifying hypervolumes constructed from functional traits representing major axes of plant strategy variation (specific leaf area, plant height, and seed mass) in tree assemblages spanning the temperate and tropical New World. Alpha-scale trait volume decreases with absolute latitude and is often lower than sampling expectation, consistent with environmental filtering theory. Beta-scale overlap decays with geographic distance fastest in the temperate zone, again consistent with environmental filtering theory. In contrast, gamma-scale trait space shows a hump-shaped relationship with absolute latitude, consistent with no theory. Furthermore, the overall temperate trait hypervolume was larger than the overall tropical hypervolume, indicating that the temperate zone permits a wider range of trait combinations or that niche packing is stronger in the tropical zone. Although there are limitations in the data, our analyses suggest that multiple processes have shaped trait diversity in trees, reflecting no consistent support for any one theory.
In this paper we present a clustering analysis of quasi-stellar objects (QSOs) using over 20000 objects from the final catalogue of the 2dF QSO Redshift Survey (2QZ), measuring the redshift-space ...two-point correlation function, ξ(s). When averaged over the redshift range 0.3 < z < 2.2 we find that ξ(s) is flat on small scales, steepening on scales above ∼25h−1 Mpc. In a WMAP/2dF cosmology (Ωm = 0.27, ΩΛ = 0.73) we find a best-fitting power law with s0 = 5.48+0.42−0.48h−1 Mpc and γ= 1.20 ± 0.10 on scales s = 1 to 25h−1 Mpc. We demonstrate that non-linear redshift-space distortions have a significant effect on the QSO ξ(s) at scales less than ∼10h−1 Mpc. A cold dark matter model assuming WMAP/2dF cosmological parameters is a good description of the QSO ξ(s) after accounting for non-linear clustering and redshift-space distortions, and allowing for a linear bias at the mean redshift of bQ(z = 1.35) = 2.02 ± 0.07. We subdivide the 2QZ into 10 redshift intervals with effective redshifts from z = 0.53 to 2.48. We find a significant increase in clustering amplitude at high redshift in the WMAP/2dF cosmology. The QSO clustering amplitude increases with redshift such that the integrated correlation function, , within 20h−1 Mpc is and . We derive the QSO bias and find it to be a strong function of redshift with bQ(z = 0.53) = 1.13 ± 0.18 and bQ(z = 2.48) = 4.24 ± 0.53. We use these bias values to derive the mean dark matter halo (DMH) mass occupied by the QSOs. At all redshifts 2QZ QSOs inhabit approximately the same mass DMHs with MDH = (3.0 ± 1.6) × 1012h−1 M⊙, which is close to the characteristic mass in the Press–Schechter mass function, M*, at z = 0. These results imply that L*Q QSOs at z∼ 0 should be largely unbiased. If the relation between black hole (BH) mass and MDH or host velocity dispersion does not evolve, then we find that the accretion efficiency (L/LEdd) for L*Q QSOs is approximately constant with redshift. Thus the fading of the QSO population from z∼ 2 to ∼0 appears to be due to less massive BHs being active at low redshift. We apply different methods to estimate, tQ, the active lifetime of QSOs and constrain tQ to be in the range 4 × 106–6 × 108 yr at z∼ 2. We test for any luminosity dependence of QSO clustering by measuring ξ(s) as a function of apparent magnitude (equivalent to luminosity relative to L*Q). However, we find no significant evidence of luminosity-dependent clustering from this data set.
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