14,549 research outputs found
Migration as a risk and a livelihood strategy: HIV across the life course of migrant families in India
Migrant workers are understood to be vulnerable to HIV. However, little is known about the experience of migration-based households following HIV infection. This qualitative study examined the migration-HIV relationship beyond the point of infection, looking at how it affects livelihood choices, household relationships and the economic viability of migrant families. We conducted semi-structured interviews with 33 HIV-positive migrant men and women recruited from an anti-retroviral therapy (ART) centre in north India. Following infection among the migrant men, contact with free, public-sector HIV services was often made late, after the development of debilitating symptoms, abandonment of migrant work and return to native villages. After enrolment at the ART centre participants’ health eventually stabilised but they now faced serious economic debt, an inflexible treatment regimen and reduced physical strength. Insecure migrant job markets, monthly drug collection and discriminatory employment policies impeded future migration plans. HIV-positive wives of migrants occupied an insecure position in the rural marital household that depended on their husbands’ health and presence of children. The migration-HIV relationship continued to shape the life course of migrant families beyond the point of infection, often exposing them again to the economic insecurity that migration had helped to overcome, threatening their long-term survival
Single women living alone in later life: a short review; understanding society
This chapter picks up the study of gender issues within ageing populations. According to OECD statistics, the UK is the loneliest country in Europe and the least likely to report having close friendships or knowing our neighbours (OECD, 2005). The number of people living on their own has doubled since the 1970s, with single-person households now making up a third of all homes. We report on the findings of our examination of some of the factors associated with health and well-being of women living alone in later life using data collected in the ‘Understanding Society’ 2012. This is a nationwide longitudinal survey that captures important information on the life course trajectories of individuals in the UK. By looking at variables associated with health and wellbeing, we have identified some relevant determinants when looking at single older women living alone. The prevalence of living alone during later life varies widely across developed countries, but everywhere its growth has been remarkable in recent decades, even in societies with traditionally strong family ties (Reher and Requena, 2017). Within the increasing trend of single women living alone over time and space, there is a need to adapt and develop more accurate measures and research designs in order to begin to understand the factors impacting on the nature of ageing for those who are living alone. Forming new intimate relationships might be one way of compensating for any loneliness associated with this phenomenon (Carr, 2004)
Going solo: exploring the intimate and broader relationships of older single women without children and the implications for their support needs in later life
This poster presents findings from a scoping study into factors which impact on successful ageing for non-partnered women without children in the UK entering retirement. Little is know about the trajectory of non-partnered women without children as they grow older in modern UK society. Our interim statistical analysis using the British Household Panel Survey demonstrates growth of women living alone as they get older. We are using this study to examine how far society is able to ascertain the trends specifically in relation to 'solo' women and the potential different 'positions' occupied by this group through the examination of different variables available for measurement in the survey. Combined with a review of the literature and study, this poster considers how to go forward to explore the key research questions that will be needed for further investigation of solo women's ageing
Sub-gap conductance in ferromagnetic-superconducting mesoscopic structures
We study the sub-gap conductance of a ferromagnetic mesoscopic region
attached to a ferromagnetic and a superconducting electrode by means of tunnel
junctions. In the absence of the exchange field, the ratio of the two tunnel junction resistances determines the behaviour of
the sub-gap conductance which possesses a zero-bias peak for and for
a peak at finite voltage. We show that the inclusion of the exchange
field leads to a peak splitting for , while it shifts the zero-bias
anomaly to finite voltages for .Comment: 5 pages revte
A Hartree-Fock Study of Persistent Currents in Disordered Rings
For a system of spinless fermions in a disordered mesoscopic ring,
interactions can give rise to an enhancement of the persistent current by
orders of magnitude. The increase in the current is associated with a charge
reorganization of the ground state. The interaction strength for which this
reorganization takes place is sample-dependent and the log-averages over the
ensemble are not representative. In this paper we demonstrate that the
Hartree-Fock method closely reproduces results obtained by exact
diagonalization. For spinless fermions subject to a short-range Coulomb
repulsion U we show that due to charge reorganization the derivative of the
persistent current is a discontinuous function of U. Having established that
the Hartree-Fock method works well in one dimension, we present corresponding
results for persistent currents in two coupled chains.Comment: 4 pages, 6 figures, Submitted to Phys. Rev.
Overcoming decoherence in the collapse and revival of spin Schr\"odinger cats
In addition to being a very interesting quantum phenomenon, Schr\"odinger cat
swapping has the potential for application in the preparation of quantum states
that could be used in metrology and other quantum processing. We study in
detail the effects of field decoherence on a cat-swapping system comprising a
set of identical qubits, or spins, all coupled to a field mode. We demonstrate
that increasing the number of spins actually mitigates the effects of field
decoherence on the collapse and revival of a spin Schr\"odinger cat, which
could be of significant utility in quantum metrology and other quantum
processing.Comment: 4 pages, 2 figure
Superconducting Proximity Effect and Universal Conductance Fluctuations
We examine universal conductance fluctuations (UCFs) in mesoscopic
normal-superconducting-normal (N-S-N) structures using a numerical solution of
the Bogoliubov - de Gennes equation. We discuss two cases depending on the
presence (``open'' structure) or absence (``closed'' structure) of
quasiparticle transmission. In contrast to N-S structures, where the onset of
superconductivity increases fluctuations, we find that UCFs are suppressed by
superconductivity for N-S-N structures. We demonstrate that the fluctuations in
``open'' and ``closed'' structures exhibit distinct responses to an applied
magnetic field and to an imposed phase variation of the superconducting order
parameter.Comment: (4 pages, 5 figures). Corrected typos in equations, added references,
changed Fig. 5 and its discussions. Phys. Rev. B, accepted for publicatio
Water vapor on supergiants. The 12 micron TEXES spectra of mu Cephei
Several recent papers have argued for warm, semi-detached, molecular layers
surrounding red giant and supergiant stars, a concept known as a MOLsphere.
Spectroscopic and interferometric analyses have often corroborated this general
picture. Here, we present high-resolution spectroscopic data of pure rotational
lines of water vapor at 12 microns for the supergiant mu Cephei. This star has
often been used to test the concept of molecular layers around supergiants.
Given the prediction of an isothermal, optically thick water-vapor layer in
Local Thermodynamic Equilibrium around the star (MOLsphere), we expected the 12
micron lines to be in emission or at least in absorption but filled in by
emission from the molecular layer around the star. Our data, however, show the
contrary; we find definite absorption. Thus, our data do not easily fit into
the suggested isothermal MOLsphere scenario. The 12 micron lines, therefore,
put new, strong constraints on the MOLsphere concept and on the nature of water
seen in signatures across the spectra of early M supergiants. We also find that
the absorption is even stronger than that calculated from a standard,
spherically symmetric model photosphere without any surrounding layers. A cool
model photosphere, representing cool outer layers is, however, able to
reproduce the lines, but this model does not account for water vapor emission
at 6 microns. Thus, a unified model for water vapor on mu Cephei appears to be
lacking. It does seem necessary to model the underlying photospheres of these
supergiants in their whole complexity. The strong water vapor lines clearly
reveal inadequacies of classical model atmospheres.Comment: Accepted for publication in the Astrophysical Journa
Rapid Estimation of Binding Constants for Cucurbit[8]uril Ternary Complexes Using Electrochemistry
upramolecular complexes are of fundamental interests in biomedicines and adaptive materials, and thus facile methods to determine their binding affinity show usefulness in the design of novel drugs and materials. Herein, we report a novel approach to estimate the binding constants K_{G2} of cucurbit[8]uril-methyl viologen-based ternary complexes (CB8-MV^{2+}-G2) using electrochemistry, achieving high precision (±0.03) and practical accuracy (±0.32) in logKG2 and short measurement time ( 0.8) between the reduction potential of CB8-MV^{2+}-G2 ternary complexes and their reported binding constants from isothermal titration calorimetry, which allow a calibration curve to be plotted based on 25 sample complexes. Mechanistic investigation using experimental and computational approaches reveals that this correlation stems from the dynamic host-guest exchange events occurring after the electron transfer step. Binding constants of unknown ternary complexes, where G2 = hydrocarbons, were estimated, illustrating potential applications for sparsely soluble second guests
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