Selective Pod Abortion by \u3ci\u3eBaptista Leucantha\u3c/i\u3e (Fabaceae) as Affected by a Curculionid Seed Predator, \u3ci\u3eApion Rostrum\u3c/i\u3e (Coleoptera)

The effect of a seed predator, Apion rostrum (Coleoptera: Curculionidae), on selective pod abortion from Baptisia leucantha (Fabaceae) was investigated in a restored tallgrass prairie plot. Weevil densities in and undamaged seed contents of attached and detached pods were compared over four occasions during the summer of 1993. Detached pods had similar to lower counts of weevils/pod and fewer seeds/pod than attached pods. Weevil density in pods appears only important in promoting pod abortIon through affects on seed number/pod as pods having fewer seeds are selectively aborted

Three-loop HTLpt thermodynamics at finite temperature and chemical potential

In this proceedings we present a state-of-the-art method of calculating thermodynamic potential at finite temperature and finite chemical potential, using Hard Thermal Loop perturbation theory (HTLpt) up to next-to-next-leading-order (NNLO). The resulting thermodynamic potential enables us to evaluate different thermodynamic quantities including pressure and various quark number susceptibilities (QNS). Comparison between our analytic results for those thermodynamic quantities with the available lattice data shows a good agreement.Comment: 5 pages, 6 figures, conference proceedings of XXI DAE-BRNS HEP Symposium, IIT Guwahati, December 2014; to appear in 'Springer Proceedings in Physics Series

Measuring the Hidden Aspects of Solar Magnetism

2008 marks the 100th anniversary of the discovery of astrophysical magnetic fields, when George Ellery Hale recorded the Zeeman splitting of spectral lines in sunspots. With the introduction of Babcock's photoelectric magnetograph it soon became clear that the Sun's magnetic field outside sunspots is extremely structured. The field strengths that were measured were found to get larger when the spatial resolution was improved. It was therefore necessary to come up with methods to go beyond the spatial resolution limit and diagnose the intrinsic magnetic-field properties without dependence on the quality of the telescope used. The line-ratio technique that was developed in the early 1970s revealed a picture where most flux that we see in magnetograms originates in highly bundled, kG fields with a tiny volume filling factor. This led to interpretations in terms of discrete, strong-field magnetic flux tubes embedded in a rather field-free medium, and a whole industry of flux tube models at increasing levels of sophistication. This magnetic-field paradigm has now been shattered with the advent of high-precision imaging polarimeters that allow us to apply the so-called "Second Solar Spectrum" to diagnose aspects of solar magnetism that have been hidden to Zeeman diagnostics. It is found that the bulk of the photospheric volume is seething with intermediately strong, tangled fields. In the new paradigm the field behaves like a fractal with a high degree of self-similarity, spanning about 8 orders of magnitude in scale size, down to scales of order 10 m.Comment: To appear in "Magnetic Coupling between the Interior and the Atmosphere of the Sun", eds. S.S. Hasan and R.J. Rutten, Astrophysics and Space Science Proceedings, Springer-Verlag, Heidelberg, Berlin, 200

Three-loop HTL gluon thermodynamics at intermediate coupling

We calculate the thermodynamic functions of pure-glue QCD to three-loop order using the hard-thermal-loop perturbation theory (HTLpt) reorganization of finite temperature quantum field theory. We show that at three-loop order hard-thermal-loop perturbation theory is compatible with lattice results for the pressure, energy density, and entropy down to temperatures $T\simeq3\;T_c$. Our results suggest that HTLpt provides a systematic framework that can used to calculate static and dynamic quantities for temperatures relevant at LHC.Comment: 24 pages, 13 figs. 2nd version: improved discussion and fixing typos. Published in JHE

Transport of persistent organic pollutants across the human placenta

Environment International 65, 107-115 (2014

Heavy oil production with energy effective steam-assisted gravity drainage

In reservoirs with extra heavy oil and bitumen, thermal methods are used to reduce the viscosity, in order to extract the oil. Steam-assisted gravity drainage (SAGD) is a thermal method where continuous steam injection is used. In this method, two horizontal wells are placed in parallel. The upper well injects steam and the lower well produces oil and condensed water. The continuous steam injection creates a chamber with uniform temperature. Heavy oil and bitumen reserves in Western Canada, which exceed 175 billion barrels, are becoming increasingly important petroleum sources due to the technical success of the SAGD processes. This study includes Computational fluid dynamics (CFD) modelling and simulations of a horizontal oil well with SAGD. The simulations are performed with inflow control devices (ICD) and autonomous inflow control valves (AICV) completion. In the SAGD processes, it is important that the residence time for steam in the reservoir is high enough to ensure that all the injected steam condenses in the reservoir to reduce the amount of steam injection and thereby making the SAGD process more energy effective. The simulations are carried out with ICD completion to delay the steam breakthrough and with AICV completion to prevent breakthrough of steam and water to the well. The numerical results showed that a most of the steam was produced together with the oil when ICD completion was used. AICV was able to close for steam and water, and the steam was thereby forced to condense in the reservoir, resulting in better utilization of the condensation energy

Seeing, Wind and Outer Scale Effects on Image Quality at the Magellan Telescopes

We present an analysis of the science image quality obtained on the twin 6.5 metre Magellan telescopes over a 1.5 year period, using images of ~10^5 stars. We find that the telescopes generally obtain significantly better image quality than the DIMM-measured seeing. This is qualitatively consistent with expectations for large telescopes, where the wavefront outer scale of the turbulence spectrum plays a significant role. However, the dominant effect is found to be wind speed with Magellan outperforming the DIMMs most markedly when the wind is strongest. Excluding data taken during strong wind conditions (>10 m/s), we find that the Magellan telescopes still significantly outperform the DIMM seeing, and we estimate the site to have L_0 ~ 25 m on average. We also report on the first detection of a negative bias in DIMM data. This is found to occur, as predicted, when the DIMM is affected by certain optical aberrations and the turbulence profile is dominated by the upper layers of the atmosphere.Comment: Accepted for publication in PASP. 10 pages, 12 figures

Connection between a possible fifth force and the direct detection of Dark Matter

If there is a fifth force in the dark sector and dark sector particles interact non-gravitationally with ordinary matter, quantum corrections generically lead to a fifth force in the visible sector. We show how the strong experimental limits on fifth forces in the visible sector constrain the direct detection cross section, and the strength of the fifth force in the dark sector. If the latter is comparable to gravity, the spin-independent direct detection cross section must typically be <~ 10^{-55} cm^2. The anomalous acceleration of ordinary matter falling towards dark matter is also constrained: \eta_{OM-DM} <~ 10^{-8}.Comment: 4 pages, 2 figures. v3: contains a more detailed treatment of the spin-dependence of the effective interaction between dark matter and ordinary matte

Self-Perceived Health and Outlook Among the Rural Elderly

Differences in life outlook and self-perceived health often attributed to age differences among the elderly were found to be more accurately explained by education. The young-old (62-74 years) and the old-old (75 years and older) were compared among 495 elderly in two rural counties in western Arkansas. The old-old were more likely than the young-old to perceive their health as better than that of others their age. But when six variables including age were entered into a predictive model for self-perceived health, differences were explained by education. That is, those with better educations rated their health more positively. There was no difference between the two age groups in sick days, although the old-old reported more days hospitalized and trips to the doctor. However, no predictive model for health status measured was statistically significant. On measures of life satisfaction, the old-old were slightly more pessimistic than the young-old. But the age difference in life outlook was explained by education when the data were controlled for other variables. The customary division of the elderly into young-old and old-old is questioned, and policy implications of the findings are discussed