Search results for "Singleton"
showing 10 items of 12 documents
Neighbourhood socio-economic characteristics and the risk of preterm birth for migrant and non-migrant women: a study in a French district
2011
Neighbourhood-level deprivation is associated with preterm birth; preterm birth rates are also higher for some, but not all migrant groups. We studied the impact of neighbourhood characteristics (a deprivation score and the proportion of foreign-born residents) on singleton preterm birth in the French district of Seine-Saint-Denis for women born in France, North Africa, sub-Saharan Africa and other countries. Multilevel logistic regression models were adjusted for maternal demographic and health care characteristics. For women born in France, the preterm birth rate rose with neighbourhood deprivation quintile (3.8% in the first to 5.7% in the fifth, adjusted odds ratio: 1.40 [95% confidence…
Additive effect of factors related to assisted conception on the reduction of maternal serum pregnancy-associated plasma protein A concentrations and…
2013
Objective To analyze whether assisted conceptions need adjustments in first-trimester Down syndrome screening and why modifications in screening markers occur. Design Eleven-year cohort retrospective analysis. Setting Maternal-fetal medicine unit. Patient(s) Two thousand eleven naturally conceived normal singleton pregnancies and 2,042 normal singleton pregnancies achieved with assisted conception: 350 by IUI and 1,692 with IVF (n = 328) or intracytoplasmic sperm injection (ICSI; n=1,364), using nondonor (n = 1,086) or donated ova (n = 606), with fresh (n = 1,432) or frozen (n = 260) embryos. Intervention(s) Comparison of ultrasound and biochemical markers of first-trimester Down syndrome s…
Some Properties of Massless Particles in Arbitrary Dimensions
1998
Various properties of two kinds of massless representations of the n-conformal (or (n+1)-De Sitter) group [Formula: see text] are investigated for n≥2. It is found that, for space-time dimensions n≥3, the situation is quite similar to the one of the n=4 case for Sn-massless representations of the n-De Sitter group [Formula: see text]. These representations are the restrictions of the singletons of [Formula: see text]. The main difference is that they are not contained in the tensor product of two UIRs with the same sign of energy when n>4, whereas it is the case for another kind of massless representations. Finally some examples of Gupta–Bleuler triplets are given for arbitrary spin and…
Exposure to elevated temperatures and risk of preterm birth in Valencia, Spain
2014
Abstract Background Prematurity is the second-leading cause of death in children under the age of 5 worldwide. It is predicted that the future climate will have more intense, longer lasting and frequent extreme heat episodes, and so the temperature effect on the risk of preterm birth is generating considerable interest in the public health field. Our aim was to explore the potential short-term effects of elevated temperatures on the risk of preterm birth in Valencia (Spain). Methods All singleton natural births born in the metropolitan area of Valencia during the warm season (May–September, 2006–2010) were included ( N =20,148). We applied time-series quasi-Poisson generalized additive mode…
Coffee and Smoking as Risk Factors of Twin Pregnancies: The Danish National Birth Cohort
2007
AbstractTwinning rates have changed substantially over time for reasons that are only partly known. In this study we studied smoking, coffee and alcohol intake, and their possible interaction with obesity as potential determinants of twinning rates using data from the Danish National Birth Cohort between 1996 and 2002. We identified 82,985 pregnancies: 81,954 singleton and 1031 twins. For the twins we had data to classify 121 as monozygotic, 189 dizygotic (same sex), 313 dizygotic (opposite sex) but, 408 were of the same sex but with unknown zygosity. All mothers were interviewed about their prepregnancy weight and height, coffee and alcohol intake, smoking habits, and potential confounding…
Risk Weighing in Twin Pregnancy
2010
Multiple pregnancies are more often associated with complications than singleton pregnancies. In our retrospective study of 613 twin pregnancies the most important risk factors in twin pregnancies were premature labour before the 37th week of gestation and the premature rupture of the membrane. The increase of perinatal mortality and morbidity for twins might be primary the result of premature delivery.
Countably compact weakly Whyburn spaces
2015
The weak Whyburn property is a generalization of the classical sequential property that was studied by many authors. A space X is weakly Whyburn if for every non-closed set \({A \subset X}\) there is a subset \({B \subset A}\) such that \({\overline{B} \setminus A}\) is a singleton. We prove that every countably compact Urysohn space of cardinality smaller than the continuum is weakly Whyburn and show that, consistently, the Urysohn assumption is essential. We also give conditions for a (countably compact) weakly Whyburn space to be pseudoradial and construct a countably compact weakly Whyburn non-pseudoradial regular space, which solves a question asked by Angelo Bella in private communica…
THREE-D SINGLETONS AND 2-D C.F.T.
1992
Two-dimensional Wess-Zumino-Novikov-Witten theory is extended to three dimensions, where it becomes a scalar gauge theory of the singleton type. The three-dimensional formulation involves a scalar field valued in a compact group G, a Nakanishi-Lautrup field valued in Lie (G) and Faddeev-Popov ghosts. The physical sector, characterized by the vanishing of the Nakanishi-Lautrup field, coincides with the WZNW theory of the group G. Three-dimensional space-time structure involves a generalized metric, but only its boundary values are of consequence. An alternative formulation in terms of left and right movers (in three dimensions!) is also possible.
Long-term prediction of birth weight
1993
On the basis of the hypothesis that undisturbed individual growth in fetal life keeps a constant proportional difference with the standard population 50th percentile, birth weight can be predicted with a single sonographic exploration after the 16th week of pregnancy. Data on 135 singleton pregnancies with accurate dates and delivery at term were used. Sonography was performed between the 17th and 36th weeks of pregnancy, in every case at least 4 weeks before delivery. The observed measurements of BPD, FL, and AC were used for the prediction of their values on the day of delivery, applying the Hadlock equation for the estimation of birth weight. The mean error of birth weight predictions wa…
Approximate solutions for two-level optimization problems
1988
This paper is devoted to general results for approximating two-level optimization problems in which the set of solutions to the lower level problem is not a singleton.