Linking maternity data for England 2007: methods and data quality

Maternity Hospital Episode Statistics (HES) data for 2007 were linked to birth registration and NHS Numbers for Babies (NN4B) data to bring together some key demographic and clinical data items not otherwise available at a national level. This extended the time period 2005-06, for which data had previously been linked and reported

Birth outcomes for African and Caribbean babies in England and Wales: retrospective analysis of routinely collected data

Objectives: To compare mean birth weights, gestational ages and odds of preterm birth and low birth weight of live singleton babies of black African or Caribbean ethnicity born in 2005 or 2006 by mother's country of birth. Design: Secondary analysis of data from linked birth registration and NHS Numbers for Babies data set. Setting: Births to women in England and Wales in 2005 and 2006. Participants: Babies of African and Caribbean ethnicity born in England and Wales in 2005–2006, whose mothers were born in African and Caribbean countries or the UK. Birth outcomes for 51 599 singleton births were analysed. Main outcome measures: Gestational age and birth weight. Results: Mothers born in Eastern or Northern Africa had babies at higher mean gestational ages (39.38 and 39.41 weeks, respectively) and lower odds of preterm birth (OR=0.80 and 0.65, respectively) compared with 39.00 weeks for babies with mothers born in the UK. Babies of African ethnicity whose mothers were born in Middle or Western Africa had mean birth weights of 3327 and 3311 g, respectively. These were significantly higher than the mean birth weight of 3257 g for babies of the UK-born mothers. Their odds of low birth weight (OR=0.75 and 0.72, respectively) were significantly lower. Babies of Caribbean ethnicity whose mothers were born in the Caribbean had higher mean birth weight and lower odds of low birth weight than those whose mothers were born in the UK. Conclusions: The study shows that in babies of African and Caribbean ethnicity, rates of low birth weight and preterm birth varied by mothers' countries of birth. Ethnicity and country of birth are important factors associated with perinatal health, but assessing them singly can mask important heterogeneity in birth outcomes within categories particularly in relation to African ethnicity. These differences should be explored further

Supersymmetric analogue of BC_N type rational integrable models with polarized spin reversal operators

We derive the exact spectra as well as partition functions for a class of $BC_N$ type of spin Calogero models, whose Hamiltonians are constructed by using supersymmetric analogues of polarized spin reversal operators (SAPSRO). The strong coupling limit of these spin Calogero models yields $BC_N$ type of Polychronakos-Frahm (PF) spin chains with SAPSRO. By applying the freezing trick, we obtain an exact expression for the partition functions of such PF spin chains. We also derive a formula which expresses the partition function of any $BC_N$ type of PF spin chain with SAPSRO in terms of partition functions of several $A_K$ type of supersymmetric PF spin chains, where $K\leq N-1$. Subsequently we show that an extended boson-fermion duality relation is obeyed by the partition functions of the $BC_N$ type of PF chains with SAPSRO. Some spectral properties of these spin chains, like level density distribution and nearest neighbour spacing distribution, are also studied.Comment: 36 pages, 2 figures. arXiv admin note: text overlap with arXiv:1402.275

Rapidly rotating strange stars for a new equation of state of strange quark matter

For a new equation of state of strange quark matter, we construct equilibrium sequences of rapidly rotating strange stars in general relativity. The sequences are the normal and supramassive evolutionary sequences of constant rest mass. We also calculate equilibrium sequences for a constant value of $\Omega$ corresponding to the most rapidly rotating pulsar PSR 1937 + 21. In addition to this, we calculate the radius of the marginally stable orbit and its dependence on $\Omega$, relevant for modeling of kilo-Hertz quasi-periodic oscillations in X-ray binaries.Comment: Two figures, uses psbox.tex and emulateapj5.st

Effect of gas flow on electronic transport in a DNA-decorated carbon nanotube

We calculate the two-time current correlation function using the experimental data of the current-time characteristics of the Gas-DNA-decorated carbon nanotube field effect transistor. The pattern of the correlation function is a measure of the sensitivity and selectivity of the sensors and suggest that these gas flow sensors may also be used as DNA sequence detectors. The system is modelled by a one-dimensional tight-binding Hamiltonian and we present analytical calculations of quantum electronic transport for the system using the time-dependent nonequilibrium Green's function formalism and the adiabatic expansion. The zeroth and first order contributions to the current $I^{(0)}(\bar{t})$ and $I^{(1)}(\bar{t})$ are calculated, where $I^{(0)} (\bar{t})$ is the Landauer formula. The formula for the time-dependent current is then used to compare the theoretical results with the experiment.Comment: 14 pages, 5 figures and 2 table

Entanglement may enhance the channel capacity in arbitrary dimensions

We consider explicitly two examples of d-dimensional quantum channels with correlated noise and show that, in agreement with previous results on Pauli qubit channels, there are situations where maximally entangled input states achieve higher values of the output mutual information than product states. We obtain a strong dependence of this effect on the nature of the noise correlations as well as on the parity of the space dimension, and conjecture that when entanglement gives an advantage in terms of mutual information, maximally entangled states achieve the channel capacity.Comment: 12 pages, 3 figure

Relevance of Induced Gauge Interactions in Decoherence

Decoherence in quantum cosmology is shown to occur naturally in the presence of induced geometric gauge interactions associated with particle production.A new 'gauge '-variant form of the semiclassical Einstein equations is also presented which makes the non-gravitating character of the vacuum polarisation energy explicit.Comment: 10 pages, LATEX, IC/94/16