Index nesting sites for the Critically Endangered hawksbill turtle
Eretmochelys
imbricata
are essential for assessing population trends and demographics, and informing conservation strategies. Using ...29 yr (1988-2017) of saturation tagging data from a protected Caribbean index site, we assessed annual trends in abundance and reproductive success for the hawksbill nesting population at Buck Island Reef National Monument (BIRNM), St. Croix, US Virgin Islands. Approximately 43 ± 21 (mean ± SD) females and 154 ± 60 nests were encountered each year during nocturnal patrols. Remigration interval and inter-nesting period averaged 3.2 ± 1.6 yr and 17.4 ± 7.1 d, respectively. After a significant recovery since 1988, female abundance stabilized during 2007-2017 (p < 0.01, R
2
= 0.82), whereas nest abundance declined (p < 0.01, R
2
= 0.71) and neophyte recruitment exhibited a decreasing trend. There was no trend in annual mean hatch success (69.4 ± 26.6%), emergence success (63.0 ± 29.1%), and hatchling production (89.2 ± 45.0 individuals clutch
-1
) during the study period; but clutch size (p < 0.01, R
2
= 0.65; 142.8 ± 28.9 eggs clutch
-1
) and female curved carapace length (p < 0.01, R
2
= 0.56; 88.4 ± 4.7 cm) significantly decreased. The BIRNM population has stabilized, but declines in body size and nest abundance highlight the need for evaluating demographics to diagnose the factor(s) driving changes in abundance and productivity. Our study provides a foundation for evaluating Caribbean hawksbill demographics, while contributing a valuable assessment of clutch size and
in situ
nest success for the species.
Access to data is a critical feature of an efficient, progressive and ultimately self-correcting scientific ecosystem. But the extent to which in-principle benefits of data sharing are realized in ...practice is unclear. Crucially, it is largely unknown whether published findings can be reproduced by repeating reported analyses upon shared data (‘analytic reproducibility’). To investigate this, we conducted an observational evaluation of a mandatory open data policy introduced at the journal Cognition. Interrupted time-series analyses indicated a substantial post-policy increase in data available statements (104/417, 25% pre-policy to 136/174, 78% post-policy), although not all data appeared reusable (23/104, 22% pre-policy to 85/136, 62%, post-policy). For 35 of the articles determined to have reusable data, we attempted to reproduce 1324 target values. Ultimately, 64 values could not be reproduced within a 10% margin of error. For 22 articles all target values were reproduced, but 11 of these required author assistance. For 13 articles at least one value could not be reproduced despite author assistance. Importantly, there were no clear indications that original conclusions were seriously impacted. Mandatory open data policies can increase the frequency and quality of data sharing. However, suboptimal data curation, unclear analysis specification and reporting errors can impede analytic reproducibility, undermining the utility of data sharing and the credibility of scientific findings.
To examine how nanoparticles influence biogeochemical cycles in streams, we studied the acute impact of nanosilver (nAg) and nanoparticulate zero-valent iron (nZVI) exposure on nutrient and oxygen ...exchange across the sediment–water interface of two streams (agricultural canal and wetland) that differed in their water quality and sediment characteristics. At the agricultural site, nAg increased oxygen consumption and decreased N₂ flux rates from that observed in control incubations. nZVI caused sediment–water systems from both streams to go hypoxic within 1.5 h of exposure. N₂ flux rates were at least an order of magnitude higher in nZVI treatments as compared to control. Water column nitrate and nitrite concentrations were not impacted by nZVI exposure but total dissolved phosphorus concentrations were higher in cores treated with nZVI. nAg and nZVI exposure to surface water ecosystems can disrupt ecological function across the sediment–water interface.
Understanding the spatial ecology of highly mobile marine vertebrates is necessary for informing conservation and management strategies aimed at protecting such species. Buck Island Reef National ...Monument (BIRNM), off the coast of St. Croix, US Virgin Islands, harbors critical foraging habitat for Critically Endangered juvenile hawksbills Eretmochelys imbricata that exhibit high site fidelity until sexual maturation. Using an array of fixed passive acoustic receivers that covered over 20.2 km2 at its largest configuration and in-water biannual sampling, we analyzed residency patterns and habitat use of 29 hawksbills. High recapture rates allowed for longterm data collection for some individuals, with 1 individual being detected within the array 1952 d (mean ± SD: 411 ± 444 d). We used detection data to construct a resource selection function based on a generalized linear mixed model in order to determine relative habitat selection, or the use of different habitat types within an area proportional to the 'true' selection. Our covariates in the model were benthic structure, bathymetry, time of day, and year. Results showed selection by tagged individuals for shallow (<20 m) depths in areas with high rugosity characterized by a high density of reef or rock. However, individuals also selected areas comprised primarily of sand interspersed with seagrass pastures. We also used the best supported model to predict relative selection across BIRNM and found that the total area of high relative selection decreased significantly at night. The information provided will help guide both future in-water surveys for cryptic hawksbills and management decisions about public area-use at BIRNM.
Pathogenic variants in the BCOR gene have been identified in males with X-linked recessive microphthalmia and in females with X-linked dominant oculofaciocardiodental (OFCD) syndrome. This latter ...condition has previously been regarded as rare but the increased availability of genetic testing in recent years has led to the identification of a greater number of patients.
We report the clinical and molecular findings in a series of 10 patients with pathogenic BCOR variants from 5 families, all seen in a single institution over a two year period.
We emphasize the phenotypic variability in this cohort and the diverse genetic mechanisms involved which included point mutations and deletions of BCOR as well as the occurrence of gonadal and somatic mosaicism.
In this report we demonstrate the novel findings of four newly identified variants in BCOR associated with an OFCD phenotype, and suggest that the frequency of this condition in females presenting with congenital cataract, including unilateral cataract, is more common than anticipated. We demonstrate the utility of screening for genetic causes of congenital cataract. Although gonadal mosaicism in OFCD had previously been reported, we demonstrate the presence of somatic mosaicism where BCOR mutations may only be detected in DNA from tissues other than blood such as buccal cells.
This study further delineates the clinical phenotype of the X-linked oculofaciocardiodental (OFCD) syndrome caused by BCOR gene abnormalities. Our families demonstrate novel molecular findings and important genetic mechanisms.
Abstract
We report the large effort that is producing comprehensive high-level young star cluster (YSC) catalogs for a significant fraction of galaxies observed with the Legacy ExtraGalactic UV ...Survey (LEGUS)
Hubble
treasury program. We present the methodology developed to extract cluster positions, verify their genuine nature, produce multiband photometry (from NUV to NIR), and derive their physical properties via spectral energy distribution fitting analyses. We use the nearby spiral galaxy NGC 628 as a test case for demonstrating the impact that LEGUS will have on our understanding of the formation and evolution of YSCs and compact stellar associations within their host galaxy. Our analysis of the cluster luminosity function from the UV to the NIR finds a steepening at the bright end and at all wavelengths suggesting a dearth of luminous clusters. The cluster mass function of NGC 628 is consistent with a power-law distribution of slopes
and a truncation of a few times 10
5
. After their formation, YSCs and compact associations follow different evolutionary paths. YSCs survive for a longer time frame, confirming their being potentially bound systems. Associations disappear on timescales comparable to hierarchically organized star-forming regions, suggesting that they are expanding systems. We find mass-independent cluster disruption in the inner region of NGC 628, while in the outer part of the galaxy there is little or no disruption. We observe faster disruption rates for low mass (≤10
4
) clusters, suggesting that a mass-dependent component is necessary to fully describe the YSC disruption process in NGC 628.
The DCC (Deleted in colorectal cancer) gene was first identified as a candidate for a tumour-suppressor gene on human chromosome 18q. More recently, in vitro studies in rodents have provided evidence ...that DCC might function as a receptor for the axonal chemoattractant netrin-1. Inactivation of the murine Dcc gene caused defects in axonal projections that are similar to those observed in netrin-1-deficient mice but did not affect growth, differentiation, morphogenesis or tumorigenesis in mouse intestine. These observations fail to support a tumour-suppressor function for Dcc, but are consistent with the hypothesis that DCC is a component of a receptor for netrin-1.
Multiple-sequential interventions were applied commercially to reduce beef carcass contamination in eight packing plants. The study evaluated microbial populations on animal hides and changes in ...carcass microbial populations at various stages in the slaughtering process. Sponge swab samples yielded mean (log CFU/100 cm2) total plate counts (TPC), total coliform counts (TCC), and Escherichia coli counts (ECC) on the exterior hide in the ranges of 8.2 to 12.5, 6.0 to 7.9, and 5.5 to 7.5, respectively, while corresponding contamination levels on carcass surfaces, after hide removal but before application of any decontamination intervention, were in the ranges of 6.1 to 9.1, 3.0 to 6.0, and 2.6 to 5.3, respectively. Following the slaughtering process and application of multiple-sequential decontamination interventions that included steam vacuuming, pre-evisceration carcass washing, pre-evisceration organic acid solution rinsing, hot water carcass washing, postevisceration final carcass washing, and postevisceration organic acid solution rinsing, mean TPC, TCC, and ECC on carcass surfaces were 3.8 to 7.1, 1.5 to 3.7, and 1.0 to 3.0, respectively, while corresponding populations following a 24 to 36 h chilling period were 2.3 to 5.3, 0.9 to 1.3, and 0.9, respectively. The results support the concept of using sequential decontamination processes in beef packing plants as a means of improving the microbiological quality of beef carcasses.
Abstract
We present the star cluster catalogues for 17 dwarf and irregular galaxies in the HST Treasury Program ‘Legacy ExtraGalactic UV Survey’ (LEGUS). Cluster identification and photometry in this ...sub-sample are similar to that of the entire LEGUS sample, but special methods were developed to provide robust catalogues with accurate fluxes due to low cluster statistics. The colours and ages are largely consistent for two widely used aperture corrections, but a significant fraction of the clusters are more compact than the average training cluster. However, the ensemble luminosity, mass, and age distributions are consistent suggesting that the systematics between the two methods are less than the random errors. When compared with the clusters from previous dwarf galaxy samples, we find that the LEGUS catalogues are more complete and provide more accurate total fluxes. Combining all clusters into a composite dwarf galaxy, we find that the luminosity and mass functions can be described by a power law with the canonical index of −2 independent of age and global SFR binning. The age distribution declines as a power law, with an index of ≈− 0.80 ± 0.15, independent of cluster mass and global SFR binning. This decline of clusters is dominated by cluster disruption since the combined star formation histories and integrated-light SFRs are both approximately constant over the last few hundred Myr. Finally, we find little evidence for an upper-mass cut-off (<2σ) in the composite cluster mass function, and can rule out a truncation mass below ≈104.5M⊙ but cannot rule out the existence of a truncation at higher masses.
Abstract
The Legacy ExtraGalactic UV Survey (LEGUS) is a multiwavelength Cycle 21 Treasury program on the
Hubble Space Telescope
. It studied 50 nearby star-forming galaxies in 5 bands from the ...near-UV to the I-band, combining new Wide Field Camera 3 observations with archival Advanced Camera for Surveys data. LEGUS was designed to investigate how star formation occurs and develops on both small and large scales, and how it relates to the galactic environments. In this paper we present the photometric catalogs for all the apparently single stars identified in the 50 LEGUS galaxies. Photometric catalogs and mosaicked images for all filters are available for download. We present optical and near-UV color–magnitude diagrams for all the galaxies. For each galaxy we derived the distance from the tip of the red giant branch. We then used the NUV color–magnitude diagrams to identify stars more massive than 14
M
⊙
, and compared their number with the number of massive stars expected from the
GALEX
FUV luminosity. Our analysis shows that the fraction of massive stars forming in star clusters and stellar associations is about constant with the star formation rate. This lack of a relation suggests that the timescale for evaporation of unbound structures is comparable or longer than 10 Myr. At low star formation rates this translates to an excess of mass in clustered environments as compared to model predictions of cluster evolution, suggesting that a significant fraction of stars form in unbound systems.
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