541 research outputs found
A Century of Service: A Centennial History of Concordia College, St. Paul
This book was written for the 100th anniversary celebration of Concordia University, Saint Paul in 1993. It is the third comprehensive history of the school that has been written, preceded by Oswald Overn\u27s A History of Concordia College in 1968 and Fred Wahlers A Short History of Concordia College in 1953. The book is organized into seven chapters. Chapter one is a summary history of Concordia\u27s first century. Chapter two is a summary of student life through the century. Chapters three through six give a more in-depth chronological development of Concordia as an academic community. Chapter seven provides a summary of changes and developments during the century.https://digitalcommons.csp.edu/csp-history/1000/thumbnail.jp
A Model for Scattering with Proliferating Resonances: Many Coupled Square Wells
We present a multichannel model for elastic interactions, comprised of an
arbitrary number of coupled finite square-well potentials, and derive
semi-analytic solutions for its scattering behavior. Despite the model's
simplicity, it is flexible enough to include many coupled short-ranged
resonances in the vicinity of the collision threshold, as is necessary to
describe ongoing experiments in ultracold molecules and lanthanide atoms. We
also introduce a simple, but physically realistic, statistical ensemble for
parameters in this model. We compute the resulting probability distributions of
nearest-neighbor resonance spacings and analyze them by fitting to the Brody
distribution. We quantify the ability of alternative distribution functions,
for resonance spacing and resonance number variance, to describe the crossover
regime. The analysis demonstrates that the multichannel square-well model with
the chosen ensemble of parameters naturally captures the crossover from
integrable to chaotic scattering as a function of closed channel coupling
strength.Comment: 11 pages, 8 figure
Many-body physics in the radio frequency spectrum of lattice bosons
We calculate the radio-frequency spectrum of a trapped cloud of cold bosonic
atoms in an optical lattice. Using random phase and local density
approximations we produce both trap averaged and spatially resolved spectra,
identifying simple features in the spectra that reveal information about both
superfluidity and correlations. Our approach is exact in the deep Mott limit
and in the deep superfluid when the hopping rates for the two internal spin
states are equal. It contains final state interactions, obeys the Ward
identities (and the associated conservation laws), and satisfies the -sum
rule. Motivated by earlier work by Sun, Lannert, and Vishveshwara [Phys. Rev. A
\textbf{79}, 043422 (2009)], we also discuss the features which arise in a
spin-dependent optical lattice.Comment: 6 pages, 4 figures, 13 subfigure
Microscopic derivation of multi-channel Hubbard models for ultracold nonreactive molecules in an optical lattice
Recent experimental advances in the cooling and manipulation of bialkali
dimer molecules have enabled the production of gases of ultracold molecules
that are not chemically reactive. It has been presumed in the literature that
in the absence of an electric field the low-energy scattering of such
nonreactive molecules (NRMs) will be similar to atoms, in which a single
-wave scattering length governs the collisional physics. However, in Ref.
[1], it was argued that the short-range collisional physics of NRMs is much
more complex than for atoms, and that this leads to a many-body description in
terms of a multi-channel Hubbard model. In this work, we show that this
multi-channel Hubbard model description of NRMs in an optical lattice is robust
against the approximations employed in Ref. [1] to estimate its parameters. We
do so via an exact, albeit formal, derivation of a multi-channel resonance
model for two NRMs from an ab initio description of the molecules in terms of
their constituent atoms. We discuss the regularization of this two-body
multi-channel resonance model in the presence of a harmonic trap, and how its
solutions form the basis for the many-body model of Ref. [1]. We also
generalize the derivation of the effective lattice model to include multiple
internal states (e.g., rotational or hyperfine). We end with an outlook to
future research.Comment: 19 pages, 4 figure
Model for scattering with proliferating resonances: Many coupled square wells
We present a multichannel model for elastic interactions, composed of an arbitrary number of coupled finite square-well potentials, and derive semianalytic solutions for its scattering behavior. Despite the model\u27s simplicity, it is flexible enough to include many coupled short-ranged resonances in the vicinity of the collision threshold, as is necessary to describe ongoing experiments in ultracold molecules and lanthanide atoms. We also introduce a simple but physically realistic statistical ensemble for parameters in this model. We compute the resulting probability distributions of nearest-neighbor resonance spacings and analyze them by fitting to the Brody distribution. We quantify the ability of alternative distribution functions, for resonance spacing and resonance number variance, to describe the crossover regime. The analysis demonstrates that the multichannel square-well model with the chosen ensemble of parameters naturally captures the crossover from integrable to chaotic scattering as a function of closed-channel coupling strength
Massilia norwichensis sp. nov., isolated from an air sample
A Gram-negative, rod-shaped and motile bacterial isolate, designated strain NS9T, isolated from
air of the Sainsbury Centre for Visual Arts in Norwich, UK, was subjected to a polyphasic
taxonomic study including phylogenetic analyses based on partial 16S rRNA, gyrB and lepA gene
sequences and phenotypic characterization. The 16S rRNA gene sequence of NS9T identified
Massilia haematophila CCUG 38318T, M. niastensis 5516S-1T (both 97.7% similarity), M.
aerilata 5516S-11T (97.4 %) and M. tieshanensis TS3T (97.4 %) as the next closest relatives. In
partial gyrB and lepA sequences, NS9T shared the highest similarities with M. haematophila
CCUG 38318T (94.5 %) and M. aerilata 5516-11T (94.3 %), respectively. These sequence data
demonstrate the affiliation of NS9T to the genus Massilia. The detection of the predominant
ubiquinone Q-8, a polar lipid profile consisting of the major compounds diphosphatidylglycerol,
phosphatidylethanolamine and phosphatidylglycerol and a polyamine pattern containing 2-
hydroxyputrescine and putrescine were in agreement with the assignment of strain NS9T to the
genus Massilia. Major fatty acids were summed feature 3 (C16 : 1v7c and/or iso-C15 : 0 2-OH),
C16 : 0, C18 : 1v7c and C10 : 0 3-OH. Dissimilarities in partial lepA and gyrB gene sequences as
well as results from DNA–DNA hybridizations demonstrate that strain NS9T is a representative of
an as-yet undescribed species of the genus Massilia that is also distinguished from its close
relatives based on physiological and biochemical traits. Hence, we describe a novel species, for
which we propose the name Massilia norwichensis sp. nov., with the type strain NS9T (5CCUG
65457T5LMG 28164T)
Stemming the Revolving Door: Teacher Retention and Attrition in Arctic Alaska Schools
Limited research is available concerning teacher retention and teacher attrition in Arctic Alaska.  This paper reports survey research findings, which identify factors related to teacher retention and attrition in Alaskan Arctic Native communities. Teacher retention rates (2009-2013) vary widely over time showing no significant trends. Results confirm that teacher turnover in rural districts is higher than in urban school districts. The authors recognize that teacher retention and attrition are multidimensional issues recommending that better communication patterns and shared responsibilities between rural school districts, local administrators, teachers, community members, and university-based teacher preparation programs be established
Anionic effects observed in complexes of trivalent lanthanides with partitioning relevant N-donor ligands
Application of technetium and rhenium carbonyl chemistry to nuclear medicine. Preparation of [NEt4]2[TcCl3(CO)3] from [NBu4][TcO4] and structure of [NEt4][Tc2(μ-Cl)3(CO)6]; structures of the model complexes [NEt4][Re2(μ-OEt)2(μ-OAc)(CO)6] and [ReBr({-CH2S(CH2)2Cl}2)(CO)3]
A detailed investigation of the one-pot synthesis of [NEt4]2[MX3(CO)3] [M=Tc (1a) or Re (1b); X= Cl−, Br−] is presented. The intermediates [NEt4][Tc2-(μ-Cl)3(CO)6] (2a), [NBu4][Tc3(μ3-H)(μ-H)3(CO)9] (3) and [Tc3(μ-H)3(CO)12] (4) have been isolated and characterized. The X-ray structure of (2a) is described. Complex (2a) crystallizes in the monoclinic space group P21/c with a=19.491(6), b=18.323(2) and c=17.497(9)AÅ, and β=97.59(2)°. Quantitative conversion of (2a), (3) and (4) into the aqua-ion [M(OH2)3(CO)3]+ [M=Tc (5a) or Re (5b)] is described. To evaluate an optimal and simple chelating group for the "fac-M(CO)3” moiety, the reaction with the bidentate thioether ligand Cl(CH2)2S(CH2)2S(CH2)2Cl (qyp) has been investigated and the structure of the neutral complex [ReBr(qyp)(CO)3] (6) is described. Complex (6) crystallizes in the monoclinic space group P21/c with a=15.935(6), b=2.788(4) and c= 7.955(10)AÅ, and β=98.57(1)°. To extend the knowledge about substitution chemistry of organometallic complexes in aqueous solution, the acetato ligand [OOCCH3]− has been reacted with (1b), resulting in the formation of the dinuclear, acetato-bridged complex [NEt4][Re2(μ-OH)2(μ-OAc)(CO)6], which converted into [Re2(μ-OEt)2(μ-OAc)(CO)6]− (7) after recrystallization from EtOH. The X-ray structure of (7) has been determined. Complex (7) crystallizes in the monoclinic space group P21/c with a=16.288(3), b=12.4272(10) and c=13.620(3)AÅ, and β=76.63(1)°. For a future application of the small "fac-M(CO)3” moiety, it seems thus advantageous to combine these two ligand groups in one simple chelating functio
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