277 research outputs found
Dynamics of Wolbachia pipientis gene expression across the Drosophila melanogaster life cycle
Symbiotic interactions between microbes and their multicellular hosts have
manifold impacts on molecular, cellular and organismal biology. To identify
candidate bacterial genes involved in maintaining endosymbiotic associations
with insect hosts, we analyzed genome-wide patterns of gene expression in the
alpha-proteobacteria Wolbachia pipientis across the life cycle of Drosophila
melanogaster using public data from the modENCODE project that was generated in
a Wolbachia-infected version of the ISO1 reference strain. We find that the
majority of Wolbachia genes are expressed at detectable levels in D.
melanogaster across the entire life cycle, but that only 7.8% of 1195 Wolbachia
genes exhibit robust stage- or sex-specific expression differences when studied
in the "holo-organism" context. Wolbachia genes that are differentially
expressed during development are typically up-regulated after D. melanogaster
embryogenesis, and include many bacterial membrane, secretion system and
ankyrin-repeat containing proteins. Sex-biased genes are often organised as
small operons of uncharacterised genes and are mainly up-regulated in adult
males D. melanogaster in an age-dependent manner suggesting a potential role in
cytoplasmic incompatibility. Our results indicate that large changes in
Wolbachia gene expression across the Drosophila life-cycle are relatively rare
when assayed across all host tissues, but that candidate genes to understand
host-microbe interaction in facultative endosymbionts can be successfully
identified using holo-organism expression profiling. Our work also shows that
mining public gene expression data in D. melanogaster provides a rich set of
resources to probe the functional basis of the Wolbachia-Drosophila symbiosis
and annotate the transcriptional outputs of the Wolbachia genome.Comment: 58 pages, 6 figures, 6 supplemental figures, 4 supplemental files
(available at
https://github.com/bergmanlab/wolbachia/tree/master/gutzwiller_et_al/arxiv
Pregnancy-Associated Hypertension in Glucose-Intolerant Pregnancy and Subsequent Metabolic Syndrome
To evaluate whether pregnancy-associated hypertension (preeclampsia or gestational hypertension), among women with varying degrees of glucose intolerance during pregnancy is associated with maternal metabolic syndrome 5-10 years later
TOI-561 b: A Low Density Ultra-Short Period "Rocky" Planet around a Metal-Poor Star
TOI-561 is a galactic thick disk star hosting an ultra-short period (0.45 day
orbit) planet with a radius of 1.37 R, making it one of the most
metal-poor ([Fe/H] = -0.41) and oldest (10 Gyr) sites where an
Earth-sized planet has been found. We present new simultaneous radial velocity
measurements (RVs) from Gemini-N/MAROON-X and Keck/HIRES, which we combined
with literature RVs to derive a mass of M=2.24 0.20 M.
We also used two new Sectors of TESS photometry to improve the radius
determination, finding R=, and confirming that
TOI-561 b is one of the lowest-density super-Earths measured to date (=
4.8 0.5 g/cm). This density is consistent with an iron-poor rocky
composition reflective of the host star's iron and rock-building element
abundances; however, it is also consistent with a low-density planet with a
volatile envelope. The equilibrium temperature of the planet (2300 K)
suggests that this envelope would likely be composed of high mean molecular
weight species, such as water vapor, carbon dioxide, or silicate vapor, and is
likely not primordial. We also demonstrate that the composition determination
is sensitive to the choice of stellar parameters, and that further measurements
are needed to determine if TOI-561 b is a bare rocky planet, a rocky planet
with an optically thin atmosphere, or a rare example of a non-primordial
envelope on a planet with a radius smaller than 1.5 R.Comment: Accepted to AJ on 11/28/202
Investigating the Atmospheric Mass Loss of the Kepler-105 Planets Straddling the Radius Gap
An intriguing pattern among exoplanets is the lack of detected planets
between approximately R and R. One proposed
explanation for this "radius gap" is the photoevaporation of planetary
atmospheres, a theory that can be tested by studying individual planetary
systems. Kepler-105 is an ideal system for such testing due to the ordering and
sizes of its planets. Kepler-105 is a sun-like star that hosts two planets
straddling the radius gap in a rare architecture with the larger planet closer
to the host star ( R, days, R, days). If photoevaporation sculpted the
atmospheres of these planets, then Kepler-105b would need to be much more
massive than Kepler-105c to retain its atmosphere, given its closer proximity
to the host star. To test this hypothesis, we simultaneously analyzed radial
velocities (RVs) and transit timing variations (TTVs) of the Kepler-105 system,
measuring disparate masses of M ( g cm) and M ( g cm). Based on these masses, the difference in gas
envelope content of the Kepler-105 planets could be entirely due to
photoevaporation (in 76\% of scenarios), although other mechanisms like
core-powered mass loss could have played a role for some planet albedos.Comment: 14 pages, 3 figures, 2 table
A genome-wide scan for common alleles affecting risk for autism
Although autism spectrum disorders (ASDs) have a substantial genetic basis, most of the known genetic risk has been traced to rare variants, principally copy number variants (CNVs). To identify common risk variation, the Autism Genome Project (AGP) Consortium genotyped 1558 rigorously defined ASD families for 1 million single-nucleotide polymorphisms (SNPs) and analyzed these SNP genotypes for association with ASD. In one of four primary association analyses, the association signal for marker rs4141463, located within MACROD2, crossed the genome-wide association significance threshold of P < 5 Ă 10â8. When a smaller replication sample was analyzed, the risk allele at rs4141463 was again over-transmitted; yet, consistent with the winner's curse, its effect size in the replication sample was much smaller; and, for the combined samples, the association signal barely fell below the P < 5 Ă 10â8 threshold. Exploratory analyses of phenotypic subtypes yielded no significant associations after correction for multiple testing. They did, however, yield strong signals within several genes, KIAA0564, PLD5, POU6F2, ST8SIA2 and TAF1C
First upper limits from LIGO on gravitational wave bursts
We report on a search for gravitational wave bursts using data from the first
science run of the LIGO detectors. Our search focuses on bursts with durations
ranging from 4 ms to 100 ms, and with significant power in the LIGO sensitivity
band of 150 to 3000 Hz. We bound the rate for such detected bursts at less than
1.6 events per day at 90% confidence level. This result is interpreted in terms
of the detection efficiency for ad hoc waveforms (Gaussians and sine-Gaussians)
as a function of their root-sum-square strain h_{rss}; typical sensitivities
lie in the range h_{rss} ~ 10^{-19} - 10^{-17} strain/rtHz, depending on
waveform. We discuss improvements in the search method that will be applied to
future science data from LIGO and other gravitational wave detectors.Comment: 21 pages, 15 figures, accepted by Phys Rev D. Fixed a few small typos
and updated a few reference
Complementary and alternative medicine use among older Australian women - a qualitative analysis
Background: The use of complementary and alternative medicines (CAM) among older adults is an emerging health issue, however little is known about older people's experiences of using CAM and the cultural, geographical and other determinants of CAM use in this population. This study used qualitative methods to explore older women's views of CAM and reasons for their use of CAM. Participants for the project were drawn from the Australian Longitudinal Study on Women's Health (ALSWH) 1921-1926 birth cohort. Women who responded positively to a question about CAM use in Survey 5 (2008) of the ALSWH were invited to participate in the study. A total of 13 rural and 12 urban women aged between 83 and 88 years agreed to be interviewed
Mild Gestational Diabetes Mellitus and Long-Term Child Health
OBJECTIVETo evaluate whether treatment of mild gestational diabetes mellitus (GDM) confers sustained offspring health benefits, including a lower frequency of obesity.RESEARCH DESIGN AND METHODSFollow-up study of children (ages 5â10) of women enrolled in a multicenter trial of treatment versus no treatment of mild GDM. Height, weight, blood pressure, waist circumference, fasting glucose, fasting insulin, triglycerides, and HDL cholesterol were measured.RESULTSFive hundred of 905 eligible offspring (55%) were enrolled. Maternal baseline characteristics were similar between the follow-up treated and untreated groups. The frequencies of BMI â„95th (20.8% and 22.9%) and 85th (32.6% and 38.6%) percentiles were not significantly different in treated versus untreated offspring (P = 0.69 and P = 0.26). No associations were observed for BMI z score, log waist circumference, log triglycerides, HDL cholesterol, blood pressure, or log HOMA-estimated insulin resistance (HOMA-IR). The effect of treatment was different by sex for fasting glucose and log HOMA-IR (P for interaction = 0.002 and 0.02, respectively) but not by age-group (5â6 and 7â10 years) for any outcomes. Female offspring of treated women had significantly lower fasting glucose levels.CONCLUSIONSAlthough treatment for mild GDM has been associated with neonatal benefits, no reduction in childhood obesity or metabolic dysfunction in the offspring of treated women was found. However, only female offspring of women treated for mild GDM had lower fasting glucose
Structure and lithology of the Japan Trench subduction plate boundary fault
The 2011 Mw9.0 Tohoku-oki earthquake ruptured to the trench with maximum coseismic slip located on the shallow portion of the plate boundary fault. To investigate the conditions and physical processes that promoted slip to the trench, Integrated Ocean Drilling Program Expedition 343/343T sailed 1 year after the earthquake and drilled into the plate boundary âŒ7 km landward of the trench, in the region of maximum slip. Core analyses show that the plate boundary dĂ©collement is localized onto an interval of smectite-rich, pelagic clay. Subsidiary structures are present in both the upper and lower plates, which define a fault zone âŒ5â15m thick. Fault rocks recovered from within the clay-rich interval contain a pervasive scaly fabric defined by anastomosing, polished, and lineated surfaces with two predominant orientations. The scaly fabric is crosscut in several places by discrete contacts across which the scaly fabric is truncated and rotated, or different rocks are juxtaposed. These contacts are inferred to be faults. The plate boundary dĂ©collement therefore contains structures resulting from both distributed and localized deformation. We infer that the formation of both of these types of structures is controlled by the frictional properties of the clay: the distributed scaly fabric formed at low strain rates associated with velocity-strengthening frictional behavior, and the localized faults formed at high strain rates characterized by velocity-weakening behavior. The presence of multiple discrete faults resulting from seismic slip within the dĂ©collement suggests that rupture to the trench may be characteristic of this margin
The TESS-Keck Survey. XV. Precise Properties of 108 TESS Planets and Their Host Stars
We present the stellar and planetary properties for 85 TESS Objects of
Interest (TOIs) hosting 108 planet candidates which comprise the TESS-Keck
Survey (TKS) sample. We combine photometry, high-resolution spectroscopy, and
Gaia parallaxes to measure precise and accurate stellar properties. We then use
these parameters as inputs to a lightcurve processing pipeline to recover
planetary signals and homogeneously fit their transit properties. Among these
transit fits, we detect significant transit-timing variations among at least
three multi-planet systems (TOI-1136, TOI-1246, TOI-1339) and at least one
single-planet system (TOI-1279). We also reduce the uncertainties on
planet-to-star radius ratios across our sample, from a median
fractional uncertainty of 8.8 among the original TOI Catalog values to
3.0 among our updated results. With this improvement, we are able to
recover the Radius Gap among small TKS planets and find that the topology of
the Radius Gap among our sample is broadly consistent with that measured among
Kepler planets. The stellar and planetary properties presented here will
facilitate follow-up investigations of both individual TOIs and broader trends
in planet properties, system dynamics, and the evolution of planetary systems.Comment: Accepted at The Astronomical Journal; 21 pages, 9 figure
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