Two-Dimensional Self-Assembly in Diblock Copolymers

Submitted to Phys. Rev. Lett.Diblock copolymers confined to a two-dimensional surface may produce uniform features of macromolecular dimensions (10 â 100 nm). We present a mathematical model for nanoscale pattern formation in such polymers which captures the dynamic evolution of a solution of poly(styrene)- b-poly(ethylene oxide), PS-b-PEO, in solvent at an air-water interface. The model has no fitting parameters and incorporates the effects of surface tension gradients, entanglement or vitrification, and diffusion. The resultant morphologies are quantitatively compared with experimental data.NS

Thermodynamics for two flavor QCD

We conclude our analysis of the N_t=6 equation of state for two flavor QCD, first described at last year's conference. We have obtained new runs at am_q=0.025 and improved runs at am_q=0.0125. The results are extrapolated to m_q=0, and we extract the speed of sound as well. We also present evidence for a restoration of the SU(2) X SU(2) chiral symmetry just above the crossover, but not of the axial U(1) chiral symmetry.Comment: Poster presented at LATTICE96(finite temperature). 4 pages, LaTeX plus 5 encapsulated Postscript figure

Chapter 19: Vulnerability of coastal and estuarine habitats in the Great Barrier Reef to climate change

This chapter attempts to address the vulnerability of the CEM in the Great Barrier Reef region to global climate change. It does not consider individual habitats (eg reefs or seagrasses) but goes beyond the individual species and habitat assessments, to consider impacts on the whole coastal marine community complex, and the ecological processes that support its functioning.This is Chapter 19 of Climate change and the Great Barrier Reef: a vulnerability assessment. The entire book can be found at http://hdl.handle.net/11017/13

VLA imaging of 12CO J = 1-0 and free-free emission in lensed submillimetre galaxies

We present a study using the Karl G. Jansky Very Large Array (VLA) of 12CO J = 1-0 emission in three strongly lensed submillimetre-selected galaxies (SMM J16359, SMM J14009 and SMM J02399) at z = 2.5-2.9. These galaxies span LIR = 1011-1013 L⊙, offering an opportunity to compare the interstellar medium of luminous infrared galaxies and ultraluminous infrared galaxies at high redshift. We estimate molecular gas masses in the range of 2-40 × 109 M⊙ using a method that assumes canonical underlying brightness temperature (Tb) ratios for star-forming and non-star-forming gas phases and a maximal star formation efficiency. A more simplistic method - using XCO = 0.8 and the measured Tb ratios - yields gas masses twice as high. In SMM J14009 we find L CO 3-2'/L CO 1-0'=0.95±0.12, indicative of warm, star-forming gas, possibly influenced by the central active galactic nucleus (AGN). We set a gas mass limit of 3σ < 6 × 108 M⊙ for the Lyman break galaxy, A2218 #384, located in the same field as SMM J16359 at z = 2.515. Finally, we use the rest-frame ˜115 GHz free-free flux densities for SMM J14009 and SMM J02399 - measurements tied directly to the photoionization rate of massive stars, and made possible by VLA's bandwidth - to estimate star formation rates (SFRs) of 400-600 M⊙ yr-1 and to estimate the fraction of LIR due to AGN

The UK risk assessment scheme for all non-native species

1. A pest risk assessment scheme, adapted from the EPPO (European and Mediterranean Plant Protection Organisation) scheme, was developed to assess the risks posed to UK species, habitats and ecosystems by non-native taxa. 2. The scheme provides a structured framework for evaluating the potential for non-native organisms, whether intentional or unintentional introductions, to enter, establish, spread and cause significant impacts in all or part of the UK. Specialist modules permit the relative importance of entry pathways, the vulnerability of receptors and the consequences of policies to be assessed and appropriate risk management options to be selected. Spreadsheets for summarising the level of risk and uncertainty, invasive attributes and economic impact were created. In addition, new methods for quantifying economic impact and summarising risk and uncertainty were explored. 3. Although designed for the UK, the scheme can readily be applied elsewhere

The diophantine equation y2 + K = x3

The effective method of Baker is applied to the equation y2 = x3 - 28 and all integral solutions are found.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/34194/1/0000483.pd

Magnetic Coordinate Systems

Geospace phenomena such as the aurora, plasma motion, ionospheric currents and associated magnetic field disturbances are highly organized by Earth's main magnetic field. This is due to the fact that the charged particles that comprise space plasma can move almost freely along magnetic field lines, but not across them. For this reason it is sensible to present such phenomena relative to Earth's magnetic field. A large variety of magnetic coordinate systems exist, designed for different purposes and regions, ranging from the magnetopause to the ionosphere. In this paper we review the most common magnetic coordinate systems and describe how they are defined, where they are used, and how to convert between them. The definitions are presented based on the spherical harmonic expansion coefficients of the International Geomagnetic Reference Field (IGRF) and, in some of the coordinate systems, the position of the Sun which we show how to calculate from the time and date. The most detailed coordinate systems take the full IGRF into account and define magnetic latitude and longitude such that they are constant along field lines. These coordinate systems, which are useful at ionospheric altitudes, are non-orthogonal. We show how to handle vectors and vector calculus in such coordinates, and discuss how systematic errors may appear if this is not done correctly

Ovarian hormones influence eating disorder symptom variability during the menopause transition: A pilot study

Objective: Eating disorder symptoms change in a predictable pattern over the menstrual cycle such that changes in symptoms are triggered by changes in the ovarian hormones estradiol (E2) and progesterone (P4). To date, work in this area has focused exclusively on young adult women. The objective of this pilot study was to examine the effect of E2 and P4 on eating disorder symptom change in midlife women during early perimenopause. Method: Participants included women aged 42–52 in early perimenopause (n = 8). In-home self-assessments were completed for one menstrual cycle or 40-days, whichever occurred first. In-home self-assessments included collecting saliva samples each morning for E2 and P4 assays and completing online study questionnaires at the end of each day. Multilevel regression models examined the associations of E2 and P4 with daily symptoms of binge eating and body dissatisfaction. Results: E2 was positively associated with binge eating when P4 was high, but not when P4 was low. E2 was inversely associated with body dissatisfaction when P4 was low, but positively associated with body dissatisfaction when P4 was high. However, the simple slopes for the effect of E2 at both high and low P4 were not significant for body dissatisfaction. Conclusions: Despite the pilot nature of this study, results are broadly consistent with the young adult literature indicating that P4 levels shape the impact of E2 on eating disorder symptoms. Larger studies with the inclusion of key moderators to account for individual heterogeneity are needed to confirm and extend these findings