2,900 research outputs found
Prenatal diagnosis of trisomy 6q25.3-qter and monosomy 10q26.12-qter by array CGH in a fetus with an apparently normal karyotype.
We present the prenatal case of a 12.5-Mb duplication involving 6q25-qter and a 12.2-Mb deletion encompassing 10q26-qter diagnosed by aCGH, while conventional karyotype showed normal results. The genotype-phenotype correlation between individual microarray and clinical findings adds to the emerging atlas of chromosomal abnormalities associated with specific prenatal ultrasound abnormalities
Maternal cell-free DNA-based screening for fetal microdeletion and the importance of careful diagnostic follow-up.
BackgroundNoninvasive prenatal screening (NIPS) by next-generation sequencing of cell-free DNA (cfDNA) in maternal plasma is used to screen for common aneuploidies such as trisomy 21 in high risk pregnancies. NIPS can identify fetal genomic microdeletions; however, sensitivity and specificity have not been systematically evaluated. Commercial companies have begun to offer expanded panels including screening for common microdeletion syndromes such as 22q11.2 deletion (DiGeorge syndrome) without reporting the genomic coordinates or whether the deletion is maternal or fetal. Here we describe a phenotypically normal mother and fetus who tested positive for atypical 22q deletion via maternal plasma cfDNA testing.MethodsWe performed cfDNA sequencing on saved maternal plasma obtained at 11 weeks of gestation from a phenotypically normal woman with a singleton pregnancy whose earlier screening at a commercial laboratory was reported to be positive for a 22q11.2 microdeletion. Fluorescence in situ hybridization and chromosomal microarray diagnostic genetic tests were done postnatally.ConclusionNIPS detected a 22q microdeletion that, upon diagnostic workup, did not include the DiGeorge critical region. Diagnostic prenatal or postnatal testing with chromosomal microarray and appropriate parental studies to determine precise genomic coordinates and inheritance should follow a positive microdeletion NIPS result
The Discovery of a Giant H-alpha Filament in NGC 7213
The nearby Seyfert galaxy NGC 7213 has been imaged in H-alpha and HI with the
CTIO 1.5 m telescope and with the Australia Telescope Compact Array (ATCA),
respectively. Optically NGC 7213 looks undisturbed and relatively featureless
but the continuum-subtracted H-alpha image shows a 19 kpc long filament located
approximately 18.6 kpc from the nucleus. The H-alpha filament could be neutral
gas photo-ionized by the active nucleus, as has been suggested for the Seyfert
galaxy NGC 5252, or shock-ionized by a jet interacting with the surrounding HI,
as has been suggested for the radio galaxy PKS 2240-41. The HI map reveals NGC
7213 to be a highly disturbed system suggesting a past merging event.Comment: 14 pages including 4 figures and 1 table. Figures 1-4 are in jpeg
format; Better quality images can be retrieved in postscript format at
ftp://charon.nmsu.edu/pub/shameed/ ; Accepted for publication in ApJ Letter
Diverging prevalences and different risk factors for childhood asthma and eczema: a cross-sectional study
This is the final version of the article. Available from BMJ Publishing Groupvia the DOI in this record.OBJECTIVE: To compare the prevalences of and risk factors for asthma, wheeze, hay fever and eczema in primary schoolchildren in Aberdeen in 2014. DESIGN: Cross-sectional survey. SETTING: Primary schools in Aberdeen, North-East Scotland. PARTICIPANTS: Children in Scottish school years primary 1-7 were handed a questionnaire by their class teacher to be completed by their parents and returned to the researchers by post or online. MAIN OUTCOME MEASURES: Lifetime history of asthma, eczema and hay fever, and recent history of wheeze. RESULTS: 41 schools agreed to participate (87%). 11,249 questionnaires were distributed and 3935 returned (35%). A parent-reported lifetime history of asthma, eczema and hay fever was present in 14%, 30% and 24% of children, respectively. The odds of lifetime asthma increased with age (OR 1.1 per year, 95% CI 1.1 to 1.2), male sex (OR 1.89, 95% CI 1.4 to 2.3), parental smoking (OR 1.7, 95% CI 1.2 to 2.3) and eczema (OR 6.6, 95% CI 5.2 to 8.4). Prevalence of recent wheeze was also reported to be 14% and was positively associated with male sex, parental smoking and eczema. In contrast, parental eczema was the only identified predictor of childhood eczema risk. CONCLUSIONS: The lifetime prevalence of asthma in primary schoolchildren was 14% in this survey, approximately half the prevalence of eczema. We report diverging prevalences in relation to previous studies in our locality, and different risk factors for asthma and eczema. These findings suggest that asthma and eczema are unlikely to have a common origin.This study was funded by Chest Heart and Stroke Scotland and a private donation from the family of Blanche Dawson, who conducted the initial 1964 Aberdeen Schools Asthma Survey
[CII] emission and star formation in the spiral arms of M31
The CII 158 microns line is the most important coolant of the interstellar
medium in galaxies but substantial variations are seen from object to object.
The main source of the emission at a galactic scale is still poorly understood.
Previous studies of the CII emission in galaxies have a resolution of several
kpc or more so the observed emission is an average of different ISM components.
The aim of this work is to study, for the first time, the CII emission at the
scale of a spiral arm. We want to investigate the origin of this line and its
use as a tracer of star formation. We present CII and OI observations of a
segment of a spiral arm of M~31 using the Infrared Space Observatory. The CII
emission is compared with tracers of neutral gas (CO, HI) and star formation
(H\alpha, Spitzer 24 mu.) The similarity of the CII emission with the Ha and 24
mu images is striking when smoothed to the same resolution, whereas the
correlation with the neutral gas is much weaker. The CII cooling rate per H
atom increases dramatically from ~2.7e-26 ergs/s/atom in the border of the map
to ~ 1.4e-25 ergs/s/atom in the regions of star formation. The CII/FIR(42-122)
ratio is almost constant at 2%, a factor 3 higher than typically quoted.
However, we do not believe that M~31 is unusual. Rather, the whole-galaxy
fluxes used for the comparisons include the central regions where the CII/FIR
ratio is known to be lower and the resolved observations neither isolate a
spiral arm nor include data as far out in the galactic disk as the observations
presented here. A fit to published PDR models yields a plausible average
solution of G_0~100 and n~3000 for the PDR emission in the regions of star
formation in the arm of M31.Comment: 8 pages, 5 figures. To be published by A&A. Low quality figures. High
quality version in http://www.obs.u-bordeaux1.fr/Radio/NRodriguez/out/m31.pd
Particularly Efficient Star Formation in M33
The Star Formation (SF) rate in galaxies is an important parameter at all
redshifts and evolutionary stages of galaxies. In order to understand the
increased SF rates in intermediate redshift galaxies one possibility is to
study star formation in local galaxies with properties frequently found at this
earlier epoch like low metallicity and small size. We present sensitive
observations of the molecular gas in M 33, a small Local Group spiral at a
distance of 840 kpc which shares many of the characteristics of the
intermediate redshift galaxies. The observations were carried out in the
CO(2--1) line with the HERA heterodyne array on the IRAM 30 m telescope. A
11\arcmin22\arcmin region in the northern part of M 33 was observed,
reaching a detection threshold of a few 10 \msol. The correlation in this
field between the CO emission and tracers of SF (8\mum, 24\mum, \Ha, FUV) is
excellent and CO is detected very far North, showing that molecular gas forms
far out in the disk even in a small spiral with a subsolar metallicity. One
major molecular cloud was discovered in an interarm region with no HI peak and
little if any signs of SF -- without a complete survey this cloud would never
have been found. The radial dependence of the CO emission has a scale length
similar to the dust emission, less extended than the \Ha or FUV. If, however,
the \ratioo ratio varies inversely with metallicity, then the scale length of
the H becomes similar to that of the \Ha or FUV. Comparing the SF rate to
the H mass shows that M 33, like the intermediate redshift galaxies it
resembles, has a significantly higher SF efficiency than large local universe
spirals.Comment: 16 pages, 15 figure
Force Training Neural Network Potential Energy Surface Models
Machine learned chemical potentials have shown great promise as alternatives
to conventional computational chemistry methods to represent the potential
energy of a given atomic or molecular system as a function of its geometry.
However, such potentials are only as good as the data they are trained on, and
building a comprehensive training set can be a costly process. Therefore, it is
important to extract as much information from training data as possible without
further increasing the computational cost. One way to accomplish this is by
training on molecular forces in addition to energies. This allows for three
additional labels per atom within the molecule. Here we develop a neural
network potential energy surface for studying a hydrogen transfer reaction
between two conformers of C5H5. We show that, for a much smaller training set,
force training can greatly improve the accuracy of the model compared to only
training to energies. We also demonstrate the importance of choosing the proper
force to energy weight ratio for the loss function to minimize the model test
error
Comparison of m-mode echocardiographic left ventricular mass measured using digital and strip chart readings: The Atherosclerosis Risk in Communities (ARIC) study
BACKGROUND: Epidemiological and clinical studies frequently use echocardiography to measure LV wall thicknesses and chamber dimension for estimating quantitative measures of LV mass. While echocardiographic M-mode LV images have traditionally been measured using hand-held calipers and strip-chart paper tracings, digitized M-mode LV image measurements made directly on the computer screen using electronic calipers have become standard practice. We sought to determine if systematic differences in LV mass occur between the two methods by comparing LV mass measured from simultaneous M-mode strip chart recordings and digitized recordings. METHODS: The Atherosclerosis Risk in Communities study applied the latter method. To determine if systematic differences in LV mass occur between the two methods, LV mass was measured from simultaneous M-mode strip chart recordings and digitized recordings. RESULTS: We found no difference in LV mass (p > .25) and a strong correlation in LV mass between the two methods (r = 0.97). Neither age, sex, nor hypertension status affected the correlation of LV mass between the two methods. CONCLUSIONS: We conclude that digital estimates of LV mass provide unbiased estimates comparable to the strip-chart method
- …