We present the results of a search for rapidly evolving transients in the Dark Energy Survey Supernova Programme. These events are characterized by fast light-curve evolution (rise to peak in ≲10 d ...and exponential decline in ≲30 d after peak). We discovered 72 events, including 37 transients with a spectroscopic redshift from host galaxy spectral features. The 37 events increase the total number of rapid optical transients by more than a factor of two. They are found at a wide range of redshifts (0.05 < z < 1.56) and peak brightnesses (-15.75 > Mg > -22.25). The multiband photometry is well fit by a blackbody up to few weeks after peak. The events appear to be hot (T ≈ 10 000–30 000 K) and large (R ≈ 1014 - 2 × 1015 cm) at peak, and generally expand and cool in time, though some events show evidence for a receding photosphere with roughly constant temperature. Spectra taken around peak are dominated by a blue featureless continuum consistent with hot, optically thick ejecta. We compare our events with a previously suggested physical scenario involving shock breakout in an optically thick wind surrounding a core-collapse supernova, we conclude that current models for such a scenario might need an additional power source to describe the exponential decline. We find that these transients tend to favour star-forming host galaxies, which could be consistent with a core-collapse origin. However, more detailed modelling of the light curves is necessary to determine their physical origin.
Abstract
We describe the Dark Energy Survey (DES) photometric data set assembled from the first three years of science operations to support DES Year 3 cosmologic analyses, and provide usage notes ...aimed at the broad astrophysics community.
Y3
GOLD
improves on previous releases from DES,
Y1
GOLD
, and Data Release 1 (DES DR1), presenting an expanded and curated data set that incorporates algorithmic developments in image detrending and processing, photometric calibration, and object classification.
Y3
GOLD
comprises nearly 5000 deg
2
of
grizY
imaging in the south Galactic cap, including nearly 390 million objects, with depth reaching a signal-to-noise ratio ∼10 for extended objects up to
i
AB
∼ 23.0, and top-of-the-atmosphere photometric uniformity <3 mmag. Compared to DR1, photometric residuals with respect to Gaia are reduced by 50%, and per-object chromatic corrections are introduced.
Y3
GOLD
augments DES DR1 with simultaneous fits to multi-epoch photometry for more robust galactic color measurements and corresponding photometric redshift estimates.
Y3
GOLD
features improved morphological star–galaxy classification with efficiency >98% and purity >99% for galaxies with 19 <
i
AB
< 22.5. Additionally, it includes per-object quality information, and accompanying maps of the footprint coverage, masked regions, imaging depth, survey conditions, and astrophysical foregrounds that are used to select the cosmologic analysis samples.
Genetic variations and adverse environmental events in utero or shortly after birth can lead to abnormal brain development and increased risk of schizophrenia. γ-Aminobutyric acid (GABA), the major ...inhibitory neurotransmitter in the mammalian brain, plays a vital role in normal brain development. GABA synthesis is controlled by enzymes derived from two glutamic acid decarboxylase (GAD) genes, GAD1 and GAD2, both of which produce transcript isoforms. While the full-length GAD1 transcript (GAD67) has been implicated in the neuropathology of schizophrenia, the transcript structure of GAD1 in the human brain has not been fully characterized. In this study, with the use of RNA sequencing and PCR technologies, we report the discovery of 10 novel transcripts of GAD1 in the human brain. Expression levels of four novel GAD1 transcripts (8A, 8B, I80 and I86) showed a lifespan trajectory expression pattern that is anticorrelated with the expression of the full-length GAD1 transcript. In addition, methylation levels of two CpG loci within the putative GAD1 promoter were significantly associated with the schizophrenia-risk SNP rs3749034 and with the expression of GAD25 in dorsolateral prefrontal cortex (DLPFC). Moreover, schizophrenia patients who had completed suicide and/or were positive for nicotine exposure had significantly higher full-length GAD1 expression in the DLPFC. Alternative splicing of GAD1 and epigenetic state appear to play roles in the developmental profile of GAD1 expression and may contribute to GABA dysfunction in the PFC and hippocampus of patients with schizophrenia.
The Dark Energy Survey: Data Release 1 Abbott, T. M. C.; Abdalla, F. B.; Allam, S. ...
The Astrophysical journal. Supplement series,
12/2018, Letnik:
239, Številka:
2
Journal Article
Recenzirano
Odprti dostop
We describe the first public data release of the Dark Energy Survey, DES DR1, consisting of reduced single-epoch images, co-added images, co-added source catalogs, and associated products and ...services assembled over the first 3 yr of DES science operations. DES DR1 is based on optical/near-infrared imaging from 345 distinct nights (2013 August to 2016 February) by the Dark Energy Camera mounted on the 4 m Blanco telescope at the Cerro Tololo Inter-American Observatory in Chile. We release data from the DES wide-area survey covering ∼5000 deg2 of the southern Galactic cap in five broad photometric bands, grizY. DES DR1 has a median delivered point-spread function of , r = 0.96, i = 0.88, z = 0.84, and Y = 0 90 FWHM, a photometric precision of <1% in all bands, and an astrometric precision of 151 . The median co-added catalog depth for a 1 95 diameter aperture at signal-to-noise ratio (S/N) = 10 is g = 24.33, r = 24.08, i = 23.44, z = 22.69, and Y = 21.44 . DES DR1 includes nearly 400 million distinct astronomical objects detected in ∼10,000 co-add tiles of size 0.534 deg2 produced from ∼39,000 individual exposures. Benchmark galaxy and stellar samples contain ∼310 million and ∼80 million objects, respectively, following a basic object quality selection. These data are accessible through a range of interfaces, including query web clients, image cutout servers, jupyter notebooks, and an interactive co-add image visualization tool. DES DR1 constitutes the largest photometric data set to date at the achieved depth and photometric precision.
Aims
To determine the incidence and predictors of tendon ruptures requiring hospitalization of representative patients with Type 2 diabetes.
Methods
A total of 1296 patients from the longitudinal ...observational Fremantle Diabetes Study, Phase I, and 5159 de‐identified age‐ and sex‐matched control subjects without diabetes from the same urban area were studied. The patients' mean (sd) age was 64.0 (11.3) years and 48.6% of them were male. Their median (interquartile range) diabetes duration was 4.0 (1.0–9.0) years. The main outcome assessed was any tendon rupture requiring hospitalization in the Fremantle Diabetes Study subjects and the matched control subjects. Independent predictors of spontaneous ruptures in the patients from the Fremantle Diabetes Study were assessed using Cox proportional hazards modelling.
Results
The incidence rate ratio for any tendon rupture requiring hospitalization in patients vs control subjects was 1.44 (95% CI 1.10–1.87; P = 0.005). Independent predictors of spontaneous ruptures in patients were BMI hazard ratio 1.05 (95% CI 1.002–1.10 for 1 kg/m2 increase; P = 0.010 and alcohol consumption hazard ratio 1.52 (95% CI 1.11–2.09) for √1 standard drink/day increase; P = 0.010. Adjustment of the incidence rate ratio for overall rupture requiring hospitalization for these variables using the BMI and alcohol consumption data from the contemporary Australian general population suggested it could be as high as 1.84.
Conclusions
There is a greater risk of tendon rupture requiring hospitalization in people with Type 2 diabetes. Alcohol consumption and adiposity are potentially modifiable risk factors of spontaneous ruptures in patients with diabetes.
What's new?
There have been no previous epidemiological studies of the risk of tendon rupture in patients with Type 2 diabetes.
In this community‐based case–control study, there was a 44% greater risk of hospitalization for any tendon rupture in subjects with Type 2 diabetes than in those without.
Independent predictors of spontaneous ruptures requiring hospitalization in the patients with diabetes were a high BMI and alcohol consumption, both potentially modifiable risk factors.
A number of analyses, meta-analyses, and assessments, including those performed by the Intergovernmental Panel on Climate Change, the National Oceanic and Atmospheric Administration, the National ...Renewable Energy Laboratory, and the International Energy Agency, have concluded that deployment of a diverse portfolio of clean energy technologies makes a transition to a low-carbon-emission energy system both more feasible and less costly than other pathways. In contrast, Jacobson et al. Jacobson MZ, Delucchi MA, Cameron MA, Frew BA (2015) Proc Natl Acad Sci USA 112(49):15060–15065 argue that it is feasible to provide “low-cost solutions to the grid reliability problem with 100% penetration of WWS wind, water and solar power across all energy sectors in the continental United States between 2050 and 2055”, with only electricity and hydrogen as energy carriers. In this paper, we evaluate that study and find significant shortcomings in the analysis. In particular, we point out that this work used invalid modeling tools, contained modeling errors, and made implausible and inadequately supported assumptions. Policy makers should treat with caution any visions of a rapid, reliable, and low-cost transition to entire energy systems that relies almost exclusively on wind, solar, and hydroelectric power.
We present the first joint analysis of cluster abundances and auto or cross-correlations of three cosmic tracer fields: galaxy density, weak gravitational lensing shear, and cluster density split by ...optical richness. From a joint analysis (4×2pt+N) of cluster abundances, three cluster cross-correlations, and the auto correlations of the galaxy density measured from the first year data of the Dark Energy Survey, we obtain Ω_{m}=0.305_{-0.038}^{+0.055} and σ_{8}=0.783_{-0.054}^{+0.064}. This result is consistent with constraints from the DES-Y1 galaxy clustering and weak lensing two-point correlation functions for the flat νΛCDM model. Consequently, we combine cluster abundances and all two-point correlations from across all three cosmic tracer fields (6×2pt+N) and find improved constraints on cosmological parameters as well as on the cluster observable-mass scaling relation. This analysis is an important advance in both optical cluster cosmology and multiprobe analyses of upcoming wide imaging surveys.
Aims/hypothesis To determine whether serum uric acid: (1) is associated with cardiovascular disease (CVD) death and/or all-cause mortality in type 2 diabetes; and (2) consistent with published data, ...predicts these outcomes in older patients and those of southern European ethnicity. Methods We studied those 1,268 (98%) of 1,294 type 2 participants in the observational Fremantle Diabetes Study who had a fasting serum uric acid measured at baseline. Mortality data were collected over a mean (±SD) 10.3 ± 3.9 years. Cox proportional hazards modelling was used to determine independent baseline predictors of CVD and all-cause death including fasting serum uric acid as a continuous variable and quartiles. Results During follow up, 525 deaths occurred (41.4% of the cohort) of which 271 (51.6%) were attributed to CVD. In univariate analyses, patients in the highest uric acid quartile had the greatest CVD and all-cause mortality (p = 0.007 and p = 0.001). After adjustment for significant variables in the most parsimonious model, baseline serum uric acid was not an independent associate of CVD or all-cause mortality whether entered as a continuous variable (HR 1.11 95% CI 0.96-1.27 and 1.10 95% CI 0.98-1.22 for a 0.1 mmol/l increase, respectively) or as quartiles (p > 0.10). Analyses of 638 patients >65 years of age and 231 of southern European ethnicity produced similar results. Conclusions/interpretation Serum uric acid was not an independent predictor of CVD or all-cause mortality in our community-based type 2 patients. Fasting serum uric acid concentrations do not appear to be prognostically useful in type 2 diabetes.
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