Letter from Isaac E. Tackett to Theophilus Brown Larimore

Letter from Isaac E. Tackett to Theophilus Brown Larimore. The four page handwritten letter is on Sabinal Christian College letterhead and is dated 25 November 1912

Orthogonal Polynomial Projectors for the Projector Augmented Wave Method of Electronic Structure Calculations

The projector augmented wave (PAW) method for electronic structure calculations developed by Blochl [Phys. Rev. B 50, 17 953 (1994)] has been very successfully used for density functional studies. It has the numerical advantages of pseudopotential techniques while retaining the physics of all-electron formalisms. We describe a method for generating the set of atom-centered projector and basis functions that are needed for the PAW method. This scheme chooses the shapes of the projector functions from a set of orthogonal polynomials multiplied by a localizing weight factor. Numerical benefits of the scheme result from having direct control of the shape of the projector functions and from the use of a simple repulsive local potential term to eliminate ‘‘ghost state’’ problems, which can plague calculations of this kind. Electronic density of states results are presented for the mineral powellite (CaMoO4)

Magnetodielectric coupling in Mn3O4

We have investigated the dielectric anomalies associated with spin ordering transitions in the tetragonal spinel Mn$_3$O$_4$, using thermodynamic, magnetic, and dielectric measurements. We find that two of the three magnetic ordering transitions in Mn$_3$O$_4$ lead to decreases in the temperature dependent dielectric constant at zero applied field. Applying a magnetic field to the polycrystalline sample leaves these two dielectric anomalies practically unchanged, but leads to an increase in the dielectric constant at the intermediate spin-ordering transition. We discuss possible origins for this magnetodielectric behavior in terms of spin-phonon coupling. Band structure calculations suggest that in its ferrimagnetic state, Mn$_3$O$_4$ corresponds to a semiconductor with no orbital degeneracy due to strong Jahn-Teller distortion.Comment: 6 pages, 7 figure

Vertical Profiles of Aerosol Optical Properties Over Central Illinois and Comparison with Surface and Satellite Measurements

Between June 2006 and September 2009, an instrumented light aircraft measured over 400 vertical profiles of aerosol and trace gas properties over eastern and central Illinois. The primary objectives of this program were to (1) measure the in situ aerosol properties and determine their vertical and temporal variability and (2) relate these aircraft measurements to concurrent surface and satellite measurements. Underflights of the CALIPSO satellite show reasonable agreement in a majority of retrieved profiles between aircraft-measured extinction at 532 nm (adjusted to ambient relative humidity) and CALIPSO-retrieved extinction, and suggest that routine aircraft profiling programs can be used to better understand and validate satellite retrieval algorithms. CALIPSO tended to overestimate the aerosol extinction at this location in some boundary layer flight segments when scattered or broken clouds were present, which could be related to problems with CALIPSO cloud screening methods. The in situ aircraft-collected aerosol data suggest extinction thresholds for the likelihood of aerosol layers being detected by the CALIOP lidar. These statistical data offer guidance as to the likelihood of CALIPSO's ability to retrieve aerosol extinction at various locations around the globe

Communicating choice: an exploration of mothers' experiences of birth

YesObjective: This article gives an in-depth insight into the ways in which communication between midwives and the birthing woman shape the birth experience. Background: Birth is a significant life event for many women that can have profound, long-lasting effects on how they see themselves as women and mothers. Within the literature the importance of control over the birth experience and the support that the birthing woman receives from midwives is stressed. Methods: Six women who had recently given birth participated in one-to-one semi-structured interviews designed to explore the kinds of support they received before, during and after their birth. An inductive thematic analysis was employed in order to identify and explore key issues which ran throughout the interviews. Results: Within the interviews the importance of being an active mother, someone who made decisions in relation to her labour, was stressed. The analysis explores the ways in which communication style and compassionate care either enabled or prevented women from adopting the position of ‘active’ mother. Conclusion: It is argued that a personal connection with midwives and clear and open communication which places the birthing woman in a position of control are key to positive birth experiences