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Prenatal vitamin intake during pregnancy and offspring obesity
Background/Objectives: In animal studies, exposure to multi-vitamins may be associated with obesity in the offspring; however, data in humans is sparse. We therefore examined the association between prenatal vitamin intake during pregnancy and offspring obesity.
Subjects/Methods: We investigated the association between prenatal vitamin intake and obesity among 29 160 mother-daughter dyads in the Nurses’ Health Study II. Mothers of participants provided information on prenatal vitamin use during pregnancy with the nurse daughter. Information on body fatness at ages 5 and 10, body mass index (BMI) at age 18, weight in 1989 and 2009, waist circumference, and height was obtained from the daughter. Polytomous logistic regression was used to predict BMI in early adulthood and adulthood, and body fatness in childhood. Linear regression was used to predict waist circumference in adulthood.
Results: In utero exposure to prenatal vitamins was not associated with body fatness, either in childhood or adulthood. Women whose mothers took prenatal vitamins during pregnancy had a covariate-adjusted odds ratio of being obese in adulthood of 0.99 (95% CI 0.92–1.05, P-value=0.68) compared to women whose mothers did not take prenatal vitamins. Women whose mothers took prenatal vitamins during pregnancy had a covariate-adjusted odds ratio of having the largest body shape at age 5 of 1.02 (95% CI 0.90–1.15, P-value=0.78). In additional analyses, in utero exposure to prenatal vitamins was also unrelated to adult abdominal adiposity.
Conclusions: Exposure to prenatal vitamins was not associated with body fatness either in childhood or in adulthood
Do the constants of nature couple to strong gravitational fields?
Recently, white dwarf stars have found a new use in the fundamental physics
community. Many prospective theories of the fundamental interactions of Nature
allow traditional constants, like the fine structure constant , to vary
in some way. A study by Berengut et al. (2013) used the Fe/Ni V line
measurements made by Preval et al. (2013) from the hot DA white dwarf G191-B2B,
in an attempt to detect any variation in . It was found that the Fe V
lines indicated an increasing alpha, whereas the Ni V lines indicated a
decreasing alpha. Possible explanations for this could be misidentification of
the lines, inaccurate atomic data, or wavelength dependent distortion in the
spectrum. We examine the first two cases by using a high S/N reference spectrum
from the hot sdO BD+284211 to calibrate the Fe/Ni V atomic data. With
this new data, we re-evaluate the work of Berengut et al. (2013) to derive a
new constraint on the variation of alpha in a gravitational field.Comment: 4 pages, 2 figures: To appear in the proceedings of the "19th
European White Dwarf Workshop" in Montreal, Canada, 201
Quasi-local energy-momentum and two-surface characterization of the pp-wave spacetimes
In the present paper the determination of the {\it pp}-wave metric form the
geometry of certain spacelike two-surfaces is considered. It has been shown
that the vanishing of the Dougan--Mason quasi-local mass , associated
with the smooth boundary of a spacelike
hypersurface , is equivalent to the statement that the Cauchy
development is of a {\it pp}-wave type geometry with pure
radiation, provided the ingoing null normals are not diverging on and the
dominant energy condition holds on . The metric on
itself, however, has not been determined. Here, assuming that the matter is a
zero-rest-mass-field, it is shown that both the matter field and the {\it
pp}-wave metric of are completely determined by the value of the
zero-rest-mass-field on and the two dimensional Sen--geometry of
provided a convexity condition, slightly stronger than above, holds. Thus the
{\it pp}-waves can be characterized not only by the usual Cauchy data on a {\it
three} dimensional but by data on its {\it two} dimensional boundary
too. In addition, it is shown that the Ludvigsen--Vickers quasi-local
angular momentum of axially symmetric {\it pp}-wave geometries has the familiar
properties known for pure (matter) radiation.Comment: 15 pages, Plain Tex, no figure
On certain quasi-local spin-angular momentum expressions for small spheres
The Ludvigsen-Vickers and two recently suggested quasi-local spin-angular
momentum expressions, based on holomorphic and anti-holomorphic spinor fields,
are calculated for small spheres of radius about a point . It is shown
that, apart from the sign in the case of anti-holomorphic spinors in
non-vacuum, the leading terms of all these expressions coincide. In non-vacuum
spacetimes this common leading term is of order , and it is the product of
the contraction of the energy-momentum tensor and an average of the approximate
boost-rotation Killing vector that vanishes at and of the 3-volume of the
ball of radius . In vacuum spacetimes the leading term is of order ,
and the factor of proportionality is the contraction of the Bel-Robinson tensor
and an other average of the same approximate boost-rotation Killing vector.Comment: 16 pages, Plain Te
Five decades of genome evolution in the globally distributed, extensively antibiotic-resistant Acinetobacter baumannii global clone 1.
The majority of Acinetobacter baumannii isolates that are multiply, extensively and pan-antibiotic resistant belong to two globally disseminated clones, GC1 and GC2, that were first noticed in the 1970s. Here, we investigated microevolution and phylodynamics within GC1 via analysis of 45 whole-genome sequences, including 23 sequenced for this study. The most recent common ancestor of GC1 arose around 1960 and later diverged into two phylogenetically distinct lineages. In the 1970s, the main lineage acquired the AbaR resistance island, conferring resistance to older antibiotics, via a horizontal gene transfer event. We estimate a mutation rate of ∼5 SNPs genome- 1 year- 1 and detected extensive recombination within GC1 genomes, introducing nucleotide diversity into the population at >20 times the substitution rate (the ratio of SNPs introduced by recombination compared with mutation was 22). The recombination events were non-randomly distributed in the genome and created significant diversity within loci encoding outer surface molecules (including the capsular polysaccharide, the outer core lipooligosaccharide and the outer membrane protein CarO), and spread antimicrobial resistance-conferring mutations affecting the gyrA and parC genes and insertion sequence insertions activating the ampC gene. Both GC1 lineages accumulated resistance to newer antibiotics through various genetic mechanisms, including the acquisition of plasmids and transposons or mutations in chromosomal genes. Our data show that GC1 has diversified into multiple successful extensively antibiotic-resistant subclones that differ in their surface structures. This has important implications for all avenues of control, including epidemiological tracking, antimicrobial therapy and vaccination
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