Abnormal infant islet morphology precedes insulin resistance in PCOS-like monkeys.

Polycystic ovary syndrome (PCOS) is prevalent in reproductive-aged women and confounded by metabolic morbidities, including insulin resistance and type 2 diabetes. Although the etiology of PCOS is undefined, contribution of prenatal androgen (PA) exposure has been proposed in a rhesus monkey model as premenopausal PA female adults have PCOS-like phenotypes in addition to insulin resistance and decreased glucose tolerance. PA female infants exhibit relative hyperinsulinemia, suggesting prenatal sequelae of androgen excess on glucose metabolism and an antecedent to future metabolic disease. We assessed consequences of PA exposure on pancreatic islet morphology to identify evidence of programming on islet development. Islet counts and size were quantified and correlated with data from intravenous glucose tolerance tests (ivGTT) obtained from dams and their offspring. Average islet size was decreased in PA female infants along with corresponding increases in islet number, while islet fractional area was preserved. Infants also demonstrated an increase in both the proliferation marker Ki67 within islets and the beta to alpha cell ratio suggestive of enhanced beta cell expansion. PA adult females have reduced proportion of small islets without changes in proliferative or apoptotic markers, or in beta to alpha cell ratios. Together, these data suggest in utero androgen excess combined with mild maternal glucose intolerance alter infant and adult islet morphology, implicating deviant islet development. Marked infant, but subtle adult, morphological differences provide evidence of islet post-natal plasticity in adapting to changing physiologic demands: from insulin sensitivity and relative hypersecretion to insulin resistance and diminished insulin response to glucose in the mature PCOS-like phenotype

Fusobacterium Chorioamnionitis: Report of Two Cases in Preterm Labor With Intact Amniotic Membranes

Background: Preterm labor (PTL) in women with intact membranes may be caused by developing chorioamnionitis. Fusobacterium displays the ability to cause chorioamnionitis in the presence of intact amniotic membrane

Swift observations of the 2006 outburst of the recurrent nova RS Ophiuchi: II. 1D hydrodynamical models of wind driven shocks

Following the early Swift X-ray observations of the latest outburst of the recurrent nova RS Ophiuchi in February 2006 (Paper I), we present new 1D hydrodynamical models of the system which take into account all three phases of the remnant evolution. The models suggest a novel way of modelling the system by treating the outburst as a sudden increase then decrease in wind mass-loss rate and velocity. The differences between this wind model and previous Primakoff-type simulations are described. A more complex structure, even in 1D, is revealed through the presence of both forward and reverse shocks, with a separating contact discontinuity. The effects of radiative cooling are investigated and key outburst parameters such as mass-loss rate, ejecta velocity and mass are varied. The shock velocities as a function of time are compared to the ones derived in Paper I. We show how the manner in which the matter is ejected controls the evolution of the shock and that for a well-cooled remnant, the shock deceleration rate depends on the amount of energy that is radiated away.Comment: 9 pages, 5 figure

Calculating energy derivatives for quantum chemistry on a quantum computer

Modeling chemical reactions and complicated molecular systems has been proposed as the `killer application' of a future quantum computer. Accurate calculations of derivatives of molecular eigenenergies are essential towards this end, allowing for geometry optimization, transition state searches, predictions of the response to an applied electric or magnetic field, and molecular dynamics simulations. In this work, we survey methods to calculate energy derivatives, and present two new methods: one based on quantum phase estimation, the other on a low-order response approximation. We calculate asymptotic error bounds and approximate computational scalings for the methods presented. Implementing these methods, we perform the world's first geometry optimization on an experimental quantum processor, estimating the equilibrium bond length of the dihydrogen molecule to within 0.014 Angstrom of the full configuration interaction value. Within the same experiment, we estimate the polarizability of the H2 molecule, finding agreement at the equilibrium bond length to within 0.06 a.u. (2% relative error).Comment: 19 pages, 1 page supplemental, 7 figures. v2 - tidied up and added example to appendice

Labour efficiency on-farm

End of project reportImprovements in milking efficiency have a greater influence than any other aspect of the dairy farmers work on overall farm labour inputs (Whipp, 1992). In order to facilitate the examination of milking process labour inputs, the milking process may be divided into the following three components: herding pre and post milking (transfer of cows to and from the milking parlour); milking (milking tasks / work routines within the parlour); and washing (washing of milking machine and yard). Meanwhile, within milking specifically, the number of cows milked per operator per hour is the best measure of both the performance of the operator and the milking installation (Clough, 1978). This is affected by the following three factors: the milking times of the cows, the number and arrangement of the milking units, and the operator’s work routine (Whipp, 1992). The addition of extra milking units will only increase milking performance if the operator has idle time during milking (Hansen, 1999)

Multi-frequency observations of a superbubble in the LMC: The case of LHA 120-N 70

We present a detailed study of new Australia Telescope Compact Array (ATCA) and XMM-Newton observations of LHA 120-N 70 (hereafter N 70), a spherically shaped object in the Large Magellanic Cloud (LMC) classified as a superbubble (SB). Both archival and new observations were used to produce high quality radio-continuum, X-ray and optical images. The radio spectral index of N 70 is estimated to be $\alpha=-0.12\pm 0.06$ indicating that while a supernova or supernovae have occurred in the region at some time in the distant past, N70 is not the remnant of a single specific supernova. N70 exhibits limited polarisation with a maximum fractional polarisation of 9% in a small area of the north west limb. We estimate the size of N 70 to have a diameter of 104 pc ($\pm 1$ pc). The morphology of N 70 in X-rays closely follows that in radio and optical, with most X-ray emission confined within the bright shell seen at longer wavelengths. Purely thermal models adequately fit the soft X-ray spectrum which lacks harder emission (above 1 keV). We also examine the pressure output of N 70 where the values for the hot (PX) and warm (PHii) phase are consistent with other studied Hii regions. However, the dust-processed radiation pressure (PIR) is significantly smaller than in any other object studied in Lopez et al. (2013). N70 is a very complex region that is likely to have had multiple factors contributing to both the origin and evolution of the entire region.Comment: 21 pages 8 figures accepted for publication in A

Catalogue of extreme wave events in Ireland: revised and updated for 14680 BP - 2017

This paper aims to extend and update the survey of extreme wave events in Ireland that was previously carried out by O’Brien et al. (2013). The original catalogue highlighted the frequency of such events dating back as far as the turn of the last ice age through to 2012. Ireland’s marine territory extends far beyond its coastline and is one of the largest seabed territories in Europe. It is therefore not surprising that extreme waves have continued to occur regularly since 2012, particularly considering the severity of weather during the winters of 2013-14 and 2015-16. In addition, a large number of storm surges have been identified since the publication of the original catalogue. This paper updates the O’Brien et al. (2013) catalogue to include events up to the end of 2016. Storm surges are included as a new category and events are categorised into long waves (tsunamis and storm surges) and short waves (storm and rogue waves). New results prior to 2012 are also included and some of the events previously documented are reclassified. Important questions regarding public safety, services and the influence of climate change are also highlighted

Polarizability of interacting atoms: Relation to collision-induced light scattering and dielectric models

The polarizability tensor of a pair of interacting He atoms has been calculated as a function of internuclear separation r using the fully self-consistent Hartree-Fock theory. It was found that the trace of the polarizability tensor, α(r), to which the second dielectric virial coefficient Bε is directly proportional, decreases with decreasing r, giving a theoretical value of Bε=-0.093 a.u. at room temperature, compared with the experimental result Bε=-0.06±0.04 a.u., measured by Orcutt and Cole [J. Chem. Phys. 46, 697 (1967)]. This is the first calculation that predicts the correct sign of Bε. We conclude that for He the effects of overlap are of opposite sign from and of sufficient magnitude to overcome the contributions of the van der Waals interaction to α(r). Furthermore, the anisotropy of the pair polarizability β(r) can be represented by a simple form: β(r)=6α2r-3-λ e-r/r0, where r0=0.74 a.u., and the collision-induced light-scattering spectrum predicted by this form has an essentially exponential line shape. These results are in qualitative agreement with recent work on collision-induced light-scattering spectra from rare gases

Shop Notes

Contains reports on four research projects