Safe abortion – Still a neglected scenario: A study of septic abortions in a tertiary hospital of Rural India

Background and Aims: In spite abortion has been legalized in India over three decades, unsafe abortion continues to be a significant contributor of maternal mortality and morbidity. The aim of the present study is to assess the magnitude of septic abortion in a tertiary care hospital over a period of three years with a special emphasis on maternal mortality and morbidity and various surgical complications. Settings and Design: Retrospective study of patients who were admitted with unsafe abortions over a three year period from 2005 to 2008 in a tertiary teaching Hospital of Rural India. Materials and Methods: Hospital records of the patients who were admitted with unsafe abortion in three years (2005-2008) were reviewed to evaluate the demographic and clinical profile in relation to age, parity, marital status, indication of abortion , the methods of abortion ,qualification of abortion provider complications and maternal mortality. Results: Unsafe abortion constitutes 11.6% ( n=132) of total abortion cases admitted over 3 years. Majority of women (70.45%) were in their thirties, married (89%).Sixty percent wanted abortion for birth spacing. Abortion methods included various primitive methods (30%) but majority by dilatation and evacuation. About 60% of abortionists were unqualified. Majority of women admitted with serious complications like peritonitis (70%), visceral injuries (60%), hemorrhagic and septic shock, renal failure (17.4%), and life threatening conditions like DIC, hepatic failure and encephalopathy. A total of 231 women died of unsafe abortion making it 12.55% of total maternal mortality in our institution. Out of 73 women requiring laparotomy, 22% were done within 24 hours of admission and majority (49%) were performed beyond 24-48 hours. Interestingly no women died when early aggressive surgery was done. Conclusion: The present study confirms that unsafe abortion is a great neglected health care problem leading to a considerable loss of maternal lives. Education and accessibility of contra caption, readily available, quality abortion services by trained abortion providers remain the key to limit mortality and morbidity arising from unsafe abortion

Fast-Light in a Photorefractive Crystal for Gravitational Wave Detection

We demonstrate superluminal light propagation using two frequency multiplexed pump beams to produce a gain doublet in a photorefractive crystal of Ce:BaTiO3. The two gain lines are obtained by two-wave mixing between a probe field and two individual pump fields. The angular frequencies of the pumps are symmetrically tuned from the frequency of the probe. The frequency difference between the pumps corresponds to the separation of the two gain lines; as it increases, the crystal gradually converts from normal dispersion without detuning to an anomalously dispersive medium. The time advance is measured as 0.28 sec for a pulse propagating through a medium with a 2Hz gain separation, compared to the same pulse propagating through empty space. We also demonstrate directly anomalous dispersion profile using a modfied experimental configuration. Finally, we discuss how anomalous dispersion produced this way in a faster photorefractive crystal (such as SPS: Sn2P2S6) could be employed to enhance the sensitivity-bandwidth product of a LIGO type gravitational wave detector augmented by a White Light Cavity.Comment: 14 pages, 5 figure

Quantum Communication and Computing With Atomic Ensembles Using Light-Shift Imbalance Induced Blockade

Recently, we have shown that for conditions under which the so-called light-shift imbalance induced blockade (LSIIB) occurs, the collective excitation of an ensemble of a multi-level atom can be treated as a closed two level system. In this paper, we describe how such a system can be used as a quantum bit (qubit) for quantum communication and quantum computing. Specifically, we show how to realize a C-NOT gate using the collective qubit and an easily accessible ring cavity, via an extension of the so-called Pellizzari scheme. We also describe how multiple, small-scale quantum computers realized using these qubits can be linked effectively for implementing a quantum internet. We describe the details of the energy levels and transitions in 87Rb atom that could be used for implementing these schemes.Comment: 16 pages, 9 figures. Accepted in Phys. Rev.

Origin of negative differential resistance in a strongly coupled single molecule-metal junction device

A new mechanism is proposed to explain the origin of negative differential resistance (NDR) in a strongly coupled single molecule-metal junction. A first-principles quantum transport calculation in a Fe-terpyridine linker molecule sandwiched between a pair of gold electrodes is presented. Upon increasing applied bias, it is found that a new phase in the broken symmetry wavefunction of the molecule emerges from the mixing of occupied and unoccupied molecular orbital. As a consequence, a non-linear change in the coupling between molecule and lead is evolved resulting to NDR. This model can be used to explain NDR in other class of metal-molecule junction device.Comment: Submitted for review on Feb 4, 200

Mediation of Long Range Charge Transfer by Kondo Bound States

We present a theory of non-equilibrium long range charge transfer between donor and acceptor centers in a model polymer mediated by magnetic exciton (Kondo) bound states. Our model produces electron tunneling lengths easily exceeding 10$\AA$, as observed recently in DNA and organic charge transfer systems. This long ranged tunneling is effective for weak to intermediate donor-bridge coupling, and is enhanced both by weak to intermediate strength Coulomb hole-electron attraction (through the orthogonality catastrophe) and by coupling to local vibrational modes.Comment: Revised content (broadened scope, vibrations added), submitted to Phys Rev Lett, added autho

Electron-Electron Interactions on the Edge States of Graphene: A Many Body Configuration Interaction Study

We have studied zigzag and armchair graphene nano ribbons (GNRs), described by the Hubbard Hamiltonian using quantum many body configuration interaction methods. Due to finite termination, we find that the bipartite nature of the graphene lattice gets destroyed at the edges making the ground state of the zigzag GNRs a high spin state, whereas the ground state of the armchair GNRs remains a singlet. Our calculations of charge and spin densities suggest that, although the electron density prefers to accumulate on the edges, instead of spin polarization, the up and down spins prefer to mix throughout the GNR lattice. While the many body charge gap results in insulating behavior for both kinds of GNRs, the conduction upon application of electric field is still possible through the edge channels because of their high electron density. Analysis of optical states suggest differences in quantum efficiency of luminescence for zigzag and armchair GNRs, which can be probed by simple experiments.Comment: 5 pages, 4 figure

Dark matter from SU(4) model

The left-right symmetric Pati-Salam model of the unification of quarks and leptons is based on SU(4) and SU(2)xSU(2) groups. These groups are naturally extended to include the classification of families of quarks and leptons. We assume that the family group (the group which unites the families) is also the SU(4) group. The properties of the 4-th generation of fermions are the same as that of the ordinary-matter fermions in first three generations except for the family charge of the SU(4)_F group: F=(1/3,1/3,1/3,-1), where F=1/3 for fermions of ordinary matter and F=-1 for the 4-th generation. The difference in F does not allow the mixing between ordinary and fourth-generation fermions. Because of the conservation of the F charge, the creation of baryons and leptons in the process of electroweak baryogenesis must be accompanied by the creation of fermions of the 4-th generation. As a result the excess n_B of baryons over antibaryons leads to the excess n_{\nu 4}=N-\bar N=n_B of neutrinos over antineutrinos in the 4-th generation. This massive fourth-generation neutrino may form the non-baryonic dark matter. In principle their mass density n_{\nu 4}m_N in the Universe can give the main contribution to the dark matter, since the lower bound on neutrino mass m_N from the data on decay of the Z-bosons is m_N > m_Z/2. The straightforward prediction of this model leads to the amount of cold dark matter relative to baryons, which is an order of magnitude bigger than allowed by observations. This inconsistency may be avoided by non-conservation of the F-charge.Comment: 9 pages, 2 figures, version accepted in JETP Letters, corrected after referee reports, references are adde