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Initiation and development of systemic necrosis in relation to virus concentration in tobacco ringspot virus-infected cowpea plants.
Notes on Autumn Collections of Diatoms from Brewer\u27s Creek, Hamilton County, Iowa
Biweekly diatom collections and chemical analyses were made in the autumn of 1970 from sites on Brewer\u27s Creek, a small central Iowa stream, and the Boone River. Eight diatom collection sites and five chemical analysis sites were used. Diatom population data and chemical data both indicate that this is a high alkaline, eutrophic stream. The creek water has a high conductivity which may, in part, explain why diatoms considered to be mesohalobous are present in the collections
Empowering Department Chairs to Facilitate Faculty Mentoring
This poster describes the progress and lessons learned as a result of newly implemented Faculty Mentoring Program in the Indiana University School of Dentistry (IUSD)
An Examination of the Process, Outcomes and Attitudes of Counselor-Trainees Participating in an Experiential Group: An Exploratory Study
This exploratory study attempts to examine the impact of experiential group work training on counselor-trainees. Survey data about group process, attitudes and outcomes were gathered from 15 counselor-trainees who were enrolled in a group-counseling course and participated in an experiential group. Correlations revealed statistically significant relationships between pre-group process variables and post-group outcome and attitude variables. The non-parametric Wilcoxon Signed Rank Test indicated significant differences between pre-group and post-group measures for the group process. Implications for future research are presented
Probing the circulation of ring-shaped Bose-Einstein condensates
This paper reports the results of a theoretical and experimental study of how
the initial circulation of ring-shaped Bose-Einstein condensates (BECs) can be
probed by time-of-flight (TOF) images. We have studied theoretically the
dynamics of a BEC after release from a toroidal trap potential by solving the
3D Gross-Pitaevskii (GP) equation. The trap and condensate characteristics
matched those of a recent experiment. The circulation, experimentally imparted
to the condensate by stirring, was simulated theoretically by imprinting a
linear azimuthal phase on the initial condensate wave function. The theoretical
TOF images were in good agreement with the experimental data. We find that upon
release the dynamics of the ring--shaped condensate proceeds in two distinct
phases. First, the condensate expands rapidly inward, filling in the initial
hole until it reaches a minimum radius that depends on the initial circulation.
In the second phase, the density at the inner radius increases to a maximum
after which the hole radius begins slowly to expand. During this second phase a
series of concentric rings appears due to the interference of ingoing and
outgoing matter waves from the inner radius. The results of the GP equation
predict that the hole area is a quadratic function of the initial circulation
when the condensate is released directly from the trap in which it was stirred
and is a linear function of the circulation if the trap is relaxed before
release. These scalings matched the data. Thus, hole size after TOF can be used
as a reliable probe of initial condensate circulation. This connection between
circulation and hole size after TOF will facilitate future studies of
atomtronic systems that are implemented in ultracold quantum gases.Comment: 9 pages, 9 figure
Improved Pseudofermion Approach for All-Point Propagators
Quark propagators with arbitrary sources and sinks can be obtained more
efficiently using a pseudofermion method with a mode-shifted action.
Mode-shifting solves the problem of critical slowing down (for light quarks)
induced by low eigenmodes of the Dirac operator. The method allows the full
physical content of every gauge configuration to be extracted, and should be
especially helpful for unquenched QCD calculations. The method can be applied
for all the conventional quark actions: Wilson, Sheikoleslami-Wohlert,
Kogut-Susskind, as well as Ginsparg-Wilson compliant overlap actions. The
statistical properties of the method are examined and examples of physical
processes under study are presented.Comment: LateX, 26 pages, 10 eps figure
Dual Labor Markets: A Theory of Labor Market Segmentation
A growing body of empirical research has documented persistent divisions among American workers: divisions by race, sex, educational credentials, industry grouping, and so forth (F. B. Weisskoff, B. Bluestone, S. Bowles and H. Gintis, D. Gordon, 1971 and 1972, B. Harrison, M. Reich, H. Wachtel and C. Betsey, and H. Zellner). These groups seem to operate in different labor markets, with different working conditions, different promotional opportunities, different wages, and different market institutions. These continuing labor market divisions pose anomalies for neoclassical economists. Orthodox theory assumes that profit-maximizing employers evaluate workers in terms of their individual characteristics and predicts that labor market differences among groups will decline over time because of competitive mechanisms (K. Arrow). But by most measures, the labor market differences among groups have not been disappearing (R. Edwards, M. Reich, and T. Weisskopf, chs. 5, 7, 8). The continuing importance of groups in the labor market thus is neither explained nor predicted by orthodox theory. Why is the labor force in general still so fragmented? Why are group characteristics repeatedly so important in the I labor market? In this paper, we summarize an emerging radical theory of labor market segmentation; we develop the full arguments in Reich, Gordon, and Edwards. The theory argues that political and economic forces within American capitalism have given rise to and perpetuated segmented labor markets, and that it is incorrect to view the sources of segmented markets as exogenous to the economic system
Baryon operators and spectroscopy in lattice QCD
The construction of the operators and correlators required to determine the
excited baryon spectrum is presented, with the aim of exploring the spatial and
spin structure of the states while minimizing the number of propagator
inversions. The method used to construct operators that transform irreducibly
under the symmetries of the lattice is detailed, and the properties of example
operators are studied using domain-wall fermion valence propagators computed on
MILC asqtad dynamical lattices.Comment: 7 pages, 2 figures, to appear in Proceedings of Workshop on Lattice
Hadron Physics 2003, Cairns, Australia, July 22 - July 30, 200
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