226 research outputs found
Leader decision making quality and subordinate performance
In the recent past, the study of transformational leaders has been the most predominant leadership research conducted. There have been strong linkages found between these behaviors and subordinate outcomes such as motivation and performance. For this reason, it was used as a base comparison for the addition of manager decision making quality. It was hypothesized that managers who make higher quality decisions will be able to guide subordinates in a more strategic fashion, ultimately increasing their motivation and performance. In addition, it was hypothesized that this effect of better decisions would be over and above that associated with transformational leader behavior.
One hundred and nine managers and two of their subordinates were surveyed to assess the managers\u27 behaviors and one of the subordinates\u27 motivation and performance. Results indicated that decision making quality did not have a direct relationship with subordinate outcomes while in line with other studies, a significant relationship was found for transformational leadership with subordinate outcomes.
The pattern of correlations suggest that decision making quality may still be an important factor, most probably as a predictor of transformational leadership. Other possibilities are proposed as well as limitations, implications and suggestions for future research
MOE11 Emittance Growth from the Thermalization of Space-Charge Nonuniformities
Beams injected into a linear focusing channel typically have some degree of
space-charge nonuniformity. In general, injected particle distributions with
systematic charge nonuniformities are not equilibria of the focusing channel
and launch a broad spectrum of collective modes. These modes can phase-mix and
have nonlinear wave-wave interactions which, at high space-charge intensities,
results in a relaxation to a more thermal-like distribution characterized by a
uniform density profile. This thermalization can transfer self-field energy
from the initial space-charge nonuniformity to the local particle temperature,
thereby increasing beam phase space area (emittance growth). In this paper, we
employ a simple kinetic model of a continuous focusing channel and build on
previous work that applied system energy and charge conservation quantify
emittance growth associated with the collective thermalization of an initial
azimuthally symmetric, rms matched beam with a radial density profile that is
hollowed or peaked. This emittance growth is shown to be surprisingly modest
even for high beam intensities with significant radial structure in the initial
density profile.Comment: Paper MOE11, XX International Linac Conference, Monterey, CA 21-25
August 2000 3 pages, 3 figure
Propionibacterium acnes and acne vulgaris: new insights from the integration of population genetic, multi-omic, biochemical and host-microbe studies.
The anaerobic bacterium Propionibacterium acnes is believed to play an important role in the pathophysiology of the common skin disease acne vulgaris. Over the last 10 years our understanding of the taxonomic and intraspecies diversity of this bacterium has increased tremendously, and with it the realisation that particular strains are associated with skin health while others appear related to disease. This extensive review will cover our current knowledge regarding the association of P. acnes phylogroups, clonal complexes and sequence types with acne vulgaris based on multilocus sequence typing of isolates, and direct ribotyping of the P. acnes strain population in skin microbiome samples based on 16S rDNA metagenomic data. We will also consider how multi-omic and biochemical studies have facilitated our understanding of P. acnes pathogenicity and interactions with the host, thus providing insights into why certain lineages appear to have a heightened capacity to contribute to acne vulgaris development, while others are positively associated with skin health. We conclude with a discussion of new therapeutic strategies that are currently under investigation for acne vulgaris, including vaccination, and consider the potential of these treatments to also perturb beneficial lineages of P. acnes on the skin
Electric/Magnetic Duality with Gauge Singlets
We demonstrate how gauge singlets can be used to find new examples of Kutasov
duality (i.e. where the matching of the dual theories relies on a non-zero
superpotential) in N}=1 SU(N) SQCD with F_Q flavours of quark and multiple
generations of adjoints, or antisymmetrics, or symmetrics. The role of the
singlets is to simplify greatly the truncation of the chiral ring whilst
maintaining an R-symmetry, and at the same time allowing an unambiguous
identification of the elementary mesons of the magnetic theory. The dual
theories satisfy all the usual tests, including the highly non-trivial 't Hooft
anomaly matching conditions.Comment: 31 pages, 2 figure
py4DSTEM: a software package for multimodal analysis of four-dimensional scanning transmission electron microscopy datasets
Scanning transmission electron microscopy (STEM) allows for imaging,
diffraction, and spectroscopy of materials on length scales ranging from
microns to atoms. By using a high-speed, direct electron detector, it is now
possible to record a full 2D image of the diffracted electron beam at each
probe position, typically a 2D grid of probe positions. These 4D-STEM datasets
are rich in information, including signatures of the local structure,
orientation, deformation, electromagnetic fields and other sample-dependent
properties. However, extracting this information requires complex analysis
pipelines, from data wrangling to calibration to analysis to visualization, all
while maintaining robustness against imaging distortions and artifacts. In this
paper, we present py4DSTEM, an analysis toolkit for measuring material
properties from 4D-STEM datasets, written in the Python language and released
with an open source license. We describe the algorithmic steps for dataset
calibration and various 4D-STEM property measurements in detail, and present
results from several experimental datasets. We have also implemented a simple
and universal file format appropriate for electron microscopy data in py4DSTEM,
which uses the open source HDF5 standard. We hope this tool will benefit the
research community, helps to move the developing standards for data and
computational methods in electron microscopy, and invite the community to
contribute to this ongoing, fully open-source project
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A core-particle model for periodically focused ion beams withintense space-charge
A core-particle model is derived to analyze transverse orbits of test particles evolving in the presence of a core ion beam that has uniform density within an elliptical cross-section. The model can be applied to both quadrupole and solenoidal focused beams in periodic or aperiodic lattices. Efficient analytical descriptions of electrostatic space-charge fields external to the beam core are derived to simplify model equations. Image charge effects are analyzed for an elliptical beam centered in a round, conducting pipe to estimate model corrections resulting from image charge nonlinearities. Transformations are employed to remove coherent flutter motion associated with oscillations of the ion beam core due to rapidly varying, linear applied focusing forces. Diagnostics for particle trajectories, Poincare phase-space projections, and single-particle emittances based on these transformations better illustrate the effects of nonlinear forces acting on particles evolving outside the core. A numerical code has been written based on this model. Example applications illustrate model characteristics. The core-particle model described has recently been applied to identify physical processes leading to space-charge transport limits for an rms matched beam in a periodic quadrupole focusing channel. Further characteristics of these processes are presented here
Short intense ion pulses for materials and warm dense matter research
We have commenced experiments with intense short pulses of ion beams on the
Neutralized Drift Compression Experiment-II at Lawrence Berkeley National
Laboratory, by generating beam spots size with radius r < 1 mm within 2 ns FWHM
and approximately 10^10 ions/pulse. To enable the short pulse durations and
mm-scale focal spot radii, the 1.2 MeV Li+ ion beam is neutralized in a
1.6-meter drift compression section located after the last accelerator magnet.
An 8-Tesla short focal length solenoid compresses the beam in the presence of
the large volume plasma near the end of this section before the target. The
scientific topics to be explored are warm dense matter, the dynamics of
radiation damage in materials, and intense beam and beam-plasma physics
including selected topics of relevance to the development of heavy-ion drivers
for inertial fusion energy. Here we describe the accelerator commissioning and
time-resolved ionoluminescence measurements of yttrium aluminium perovskite
using the fully integrated accelerator and neutralized drift compression
components.Comment: 7 pages, 9 figure
Material Need Insecurities, Control of Diabetes Mellitus, and Use of Health Care Resources: Results of the Measuring Economic Insecurity in Diabetes Study
Increasing access to care may be insufficient to improve health for diabetes patients with unmet basic needs. However, how specific material need insecurities relate to clinical outcomes and care utilization in a setting of near-universal care access is unclear
Strong coupling, discrete symmetry and flavour
We show how two principles - strong coupling and discrete symmetry - can work
together to generate the flavour structure of the Standard Model. We propose
that in the UV the full theory has a discrete flavour symmetry, typically only
associated with tribimaximal mixing in the neutrino sector. Hierarchies in the
particle masses and mixing matrices then emerge from multiple strongly coupled
sectors that break this symmetry. This allows for a realistic flavour
structure, even in models built around an underlying grand unified theory. We
use two different techniques to understand the strongly coupled physics:
confinement in N=1 supersymmetry and the AdS/CFT correspondence. Both
approaches yield equivalent results and can be represented in a clear,
graphical way where the flavour symmetry is realised geometrically.Comment: 31 pages, 5 figures, updated references and figure
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