1,036 research outputs found
Science with an ngVLA: Resolving the Radio Complexity of EXor and FUor-type Systems with the ngVLA
Episodic accretion may be a common occurrence in the evolution of young
pre-main sequence stars and has important implications for our understanding of
star and planet formation. Many fundamental aspects of what drives the
accretion physics, however, are still unknown. The ngVLA will be a key tool in
understanding the nature of these events. The high spatial resolution, broad
spectral coverage, and unprecedented sensitivity will allow for the detailed
analysis of outburst systems. The proposed frequency range of the ngVLA allows
for observations of the gas, dust, and non-thermal emission from the star and
disk.Comment: 8 pages, 1 figure, To be published in the ASP Monograph Series,
"Science with a Next-Generation VLA", ed. E. J. Murphy (ASP, San Francisco,
CA
Stellar models and isochrones from low-mass to massive stars including pre-main sequence phase with accretion
Grids of stellar models are useful tools to derive the properties of stellar
clusters, in particular young clusters hosting massive stars, and to provide
information on the star formation process in various mass ranges. Because of
their short evolutionary timescale, massive stars end their life while their
low-mass siblings are still on the pre-main sequence (pre-MS) phase. Thus the
study of young clusters requires consistent consideration of all the phases of
stellar evolution. But despite the large number of grids that are available in
the literature, a grid accounting for the evolution from the pre-MS accretion
phase to the post-MS phase in the whole stellar mass range is still lacking. We
build a grid of stellar models at solar metallicity with masses from 0.8
to 120 , including pre-MS phase with accretion. We use the
{\sc genec} code to run stellar models on this mass range. The accretion law is
chosen to match the observations of pre-MS objects on the Hertzsprung-Russell
diagram. We describe the evolutionary tracks and isochrones of our models. The
grid is connected to previous MS and post-MS grids computed with the same
numerical method and physical assumptions, which provides the widest grid in
mass and age to date. Numerical tables of our models and corresponding
isochrones are available online
Water in a Changing World
Life on earth depends on the continuous flow of materials through the air, water, soil, and food webs of the biosphere. The movement of water through the hydrological cycle comprises the largest of these flows, delivering an estimated I 10,000 cubic kilometers (km^\u3e of water to the land each year as snow and rainfall. Solar energy drives the hydrological cycle, vaporizing water from the surface of oceans, lakes, and rivers as well as from soils and plants (evapotranspiration). Water vapor rises into the atmosphere where it cools, condenses, and eventually rains down anew. This renewable freshwater supply sustains life on the land, in estuaries, and in the freshwater ecosystems of the earth
Efficient at-most-once messages based on synchronized clocks
This paper describes a new message passing protocol that provides guaranteed detection of duplicate messages even when the receiver has no state stored for the sender
Ordered subset linkage analysis supports a susceptibility locus for age-related macular degeneration on chromosome 16p12
BACKGROUND: Age-related macular degeneration (AMD) is a complex disorder that is responsible for the majority of central vision loss in older adults living in developed countries. Phenotypic and genetic heterogeneity complicate the analysis of genome-wide scans for AMD susceptibility loci. The ordered subset analysis (OSA) method is an approach for reducing heterogeneity, increasing statistical power for detecting linkage, and helping to define the most informative data set for follow-up analysis. OSA assesses the linkage evidence in subsets of potentially more homogeneous families by rank-ordering family-specific lod scores with respect to trait-associated covariates or phenotypic features. Here, we present results of incorporating five continuous covariates into our genome-wide linkage analysis of 389 microsatellite markers in 62 multiplex families: Body mass index (BMI), systolic (SBP) and diastolic (DBP) blood pressure, intraocular pressure (IOP), and pack-years of cigarette smoking. Chromosome-wide significance of increases in nonparametric multipoint lod scores in covariate-defined subsets relative to the overall sample was assessed by permutation. RESULTS: Using a correction for testing multiple covariates, statistically significant lod score increases were observed for two chromosomal regions: 14q13 with a lod score of 3.2 in 28 families with average IOP ≤ 15.5 (p = 0.002), and 6q14 with a lod score of 1.6 in eight families with average BMI ≥ 30.1 (p = 0.0004). On chromosome 16p12, nominally significant lod score increases (p ≤ 0.05), up to a lod score of 2.9 in 32 families, were observed with several covariate orderings. While less significant, this was the only region where linkage evidence was associated with multiple clinically meaningful covariates and the only nominally significant finding when analysis was restricted to advanced forms of AMD. Families with linkage to 16p12 had higher averages of SBP, IOP and BMI and were primarily affected with neovascular AMD. For all three regions, linkage signals at or very near the peak marker have previously been reported. CONCLUSION: Our results suggest that a susceptibility gene on chromosome 16p12 may predispose to AMD, particularly to the neovascular form, and that further research into the previously suggested association of neovascular AMD and systemic hypertension is warranted
Design decisions for a real time, alcohol craving study using physio- and psychological measures
The current study was a pilot for an alcohol craving monitoring study with a biosensor (E4 wristband) and ecological momentary assessment (EMA) smartphone app. The E4 wristband was evaluated on compliance rates, usability, comfort and stigmatization. Two EMA methodologies (signal- and interval-contingent design) were compared on data variability, compliance and perceived burden. Results show that both EMA methodologies captured variability of craving and compliance rates were between medium to low. The perceived burden of the designs was high, in particular for the signal-contingent design. Participants wore the wristband ranging from occasionally to often and the usability was rated good. Many participants reported frequent questioning about the bracelet, which they indicated as positive. However, addicted individuals are expected not to appreciate this attention, we therefore propose to provide them with coping strategies. Efforts should be made to increase compliance, we therefore propose the interval contingent design with micro incentives
Indapamide-induced transient myopia with supraciliary effusion: case report.
BACKGROUND: Ingestion of sulphonamide-derived drugs has been reported to possibly have ocular side-effects. Authors aimed to present a rare case of indapamide-induced transient myopia with ciliary body edema and supraciliary effusion. CASE PRESENTATION: A 39 years old caucasian female patient presented at the Department of Neurology with headache and sudden bilateral loss of distant vision. Neurological assessment and cranial CT scans were unremarkable. For her hypertension, twice a day bisoprolol 2.5 mg and once a day indapamide 1.5 mg tablets were prescribed several days before. At her presenting, ophthalmic findings were as follows: visual acuity 0.08-7.25Dsph = 1.0 and 0.06-7.25Dsph = 1.0; IOP 25 mmHg and 24 mmHg, anterior chamber depth (ACD) 2.32 mm and 2.49 mm, lens thickness (L) 4.02 mm and 4.09 mm in the right and the left eye, respectively. By means of ultrasound biomicroscopy (UBM), thickened (720 / 700 micron) and detached ciliary body, its forward movement (ciliary body-cornea angle 108[prime] / 114[prime]) and forward rotated ciliary processes were seen. Angle opening distance (AOD500) were 300 / 314 microns. By the following days, the myopia gradually diminished, and a week after her first symptoms, her uncorrected visual acuity was 1.0 in both eyes, IOP 13 mmHg and 17 mmHg, ACD 3.68 mm and 3.66 mm, L 3.78 mm and 3.81 mm in the right and the left eye, respectively. Ciliary body edema and detachment disappeared (ciliary body thickness 225 / 230 micron), both of the ciliary body-cornea angle 134[prime] / 140[prime] and the AOD500 (650 / 640 microns) increased. At this point, the patient admitted that she had stopped taking indapamide two days before. CONCLUSIONS: Our case report is the third one in the literature to present indapamide-induced transient myopia, and the first to employ UBM for describing the characteristics of this rare condition. According to the findings, authors suggest that both ciliary muscle contraction and ciliary body edema may play role in the pathomechanism. UBM seems to be a useful tool in the differential diagnosis of acute myopia. Further, authors wish to draw attention to one of the potential adverse effects of this drug which was not listed by its package insert
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