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University Heights, IA, United States

Drake University is a private, co-educational university located in Des Moines, Iowa, USA. The institution offers a number of undergraduate and graduate programs, as well as professional programs in business, law and pharmacy. Drake is one of the twenty-five oldest law schools in the country. Wikipedia.

Haedicke M.A.,Drake University
Sociological Quarterly | Year: 2012

Institutional theory has played a central role in the study of organizations for over half a century, but it often overlooks the actions of the people who bring organizations to life. This article advances an inhabited approach to institutional analysis that foregrounds the creativity of organizational members. It argues that people use local cultures to translate and respond to institutional pressures. The article analyzes qualitative data from countercultural co-op stores that have been pushed to conform to mainstream forms of business organization by a competitive market and demonstrates that translation explains why outcomes that institutional theory would not predict have come to pass. © 2012 Midwest Sociological Society. Source

Rieck M.Q.,Drake University
Journal of Mathematical Imaging and Vision | Year: 2012

In the Perspective 3-Point Pose Problem (P3P), the transformation that converts the triple of (unknown) camera-to-control-point distances, into the triple of (known) angle cosines between the projection lines, is generally locally invertible. However, this fails to be the case when the camera's focal point (center of perspective) is on the danger cylinder. This situation corresponds to a double solution to P3P, and presents extra difficulties in solving P3P. An extensive analysis of the danger cylinder setup leads to the introduction of a special rational function that proves to be quite useful in solving P3P in the danger cylinder case. This involves some rather long algebraic expressions that are best manipulated using mathematical software. Ultimately, some fairly simple formulas emerge that serve as a basis for an algorithm, called the Double Solution Algorithm (DSA). Experimental results comparing DSA with Grunert's quartic polynomial method demonstrate that DSA often has substantially greater accuracy. This is particularly so when the camera is relatively far from the control points, even if it is not very close to the danger cylinder. © 2011 Springer Science+Business Media, LLC. Source

Tills O.,Drake University
Proceedings. Biological sciences / The Royal Society | Year: 2013

Understanding the link between ontogeny (development) and phylogeny (evolution) remains a key aim of biology. Heterochrony, the altered timing of developmental events between ancestors and descendants, could be such a link although the processes responsible for producing heterochrony, widely viewed as an interspecific phenomenon, are still unclear. However, intraspecific variation in developmental event timing, if heritable, could provide the raw material from which heterochronies originate. To date, however, heritable developmental event timing has not been demonstrated, although recent work did suggest a genetic basis for intraspecific differences in event timing in the embryonic development of the pond snail, Radix balthica. Consequently, here we used high-resolution (temporal and spatial) imaging of the entire embryonic development of R. balthica to perform a parent-offspring comparison of the timing of twelve, physiological and morphological developmental events. Between-parent differences in the timing of all events were good predictors of such timing differences between their offspring, and heritability was demonstrated for two of these events (foot attachment and crawling). Such heritable intraspecific variation in developmental event timing could be the raw material for speciation events, providing a fundamental link between ontogeny and phylogeny, via heterochrony. Source

Bartschat K.,Drake University
Journal of Physics D: Applied Physics | Year: 2013

An overview of computational methods that have been used extensively to generate atomic data for electron-atom collisions is presented. Particular emphasis is placed on approaches whose data have been used for modelling applications in plasma physics. Examples illustrate the strengths and weaknesses of these methods and hence their likely range of applicability. © 2013 IOP Publishing Ltd. Source

Tayal S.S.,Clark Atlanta University | Zatsarinny O.,Drake University
Astrophysical Journal, Supplement Series | Year: 2010

New improved calculations are reported for transition probabilities and electron impact excitation collision strengths for the astrophysically important lines in S II. The collision strengths have been calculated in the close-coupling approximation using the B-spline Breit-Pauli R-matrix method. The multiconfiguration Hartree-Fock method with term-dependent non-orthogonal orbitals is employed for an accurate representation of the target wave functions. The close-coupling expansion includes 70 bound levels of S II covering all possible terms of the ground 3s 23p 3 and singly excited 3s3p 4, 3s 23p 23d, 3s 23p 24s, and 3s 23p 24p configurations. The present calculations are more extensive than previous ones, leading to a total 2415 transitions between fine-structure levels. The effective collision strengths are obtained by averaging the electron collision strengths over a Maxwellian distribution of velocities and these are tabulated for all fine-structure transitions at electron temperatures in the range from 5000 to 100,000 K. The present results are compared with a variety of other close-coupling calculations and available experimental data. There is an overall good agreement with the recent 18-state calculations by Ramsbottom, Bell, & Stafford and with the 19-state calculations by Tayal for the most part, but some significant differences are also noted for some transitions. © 2010. The American Astronomical Society. All rights reserved. Source

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