3,292 research outputs found
Market Orientation, Innovativeness, and Performance of Food Companies
Food processors have seen escalating levels of competition over the past three decades. An underlying objective of this research is to gain a greater understanding of how food companies thrive in the face of this increased competition. This study incorporates market orientation theory (competitor orientation, customer orientation, and interfunctional coordination) and firm innovativeness to explain differences in firm financial performance. A national survey of food processors was conducted and structural equation modeling was used to test the hypotheses. The results show that the more successful firms are more internally focused (interfunctional coordination and innovativeness) than externally focused (competitor and customer orientation).firm performance, food industry, innovativeness, market orientation, structural equation modeling, Agribusiness, Marketing,
Self-diffusion of Rod-like Viruses Through Smectic Layer
We report the direct visualization at the scale of single particles of mass
transport between smectic layers, also called permeation, in a suspension of
rod-like viruses. Self-diffusion takes place preferentially in the direction
normal to the smectic layers, and occurs by quasi-quantized steps of one rod
length. The diffusion rate corresponds with the rate calculated from the
diffusion in the nematic state with a lamellar periodic ordering potential that
is obtained experimentally.Comment: latex, 4 pages, 4 figures, accepted in Phys. Rev. Let
Assessment of Land-Use Impacts of Highways in Small Urban Areas
Evaluating existing techniques for assessing the secondary land-use impacts of highway projects on small communities, three promising techniques were applied to case studies in Wausau, Eau Claire, Sheboygan, and Wisconsin Rapids. These techniques were: a structured expert panel evaluation, a Lowry land-use model, and a quantitative checklist\u27\u27 approach. This report summarizes the advantages and limitations of each approach for forecasting secondary land-use impacts of highways.https://dc.uwm.edu/caupr_mono/1003/thumbnail.jp
Dynamic Microclimate Boundaries across a Sharp Tropical Rainforest–Clearing Edge
As landscapes become increasingly fragmented, research into impacts from disturbance and how edges affect vegetation and community structure has become more important. Descriptive studies on how microclimate changes across sharp transition zones have long existed in the literature and recently more attention has been focused on understanding the dynamic patterns of microclimate associated with forest edges. Increasing concern about forest fragmentation has led to new technologies for modeling forest microclimates. However, forest boundaries pose important challenges to not only microclimate modeling but also sampling regimes in order to capture the diurnal and seasonal dynamic aspects of microclimate along forest edges. We measured microclimatic variables across a sharp boundary from a clearing into primary lowland tropical rainforest at La Selva Biological Station in Costa Rica. Dynamic changes in diurnal microclimate were measured along three replicated transects, approximately 30 m in length with data collected every 1 m continuously at 30 min intervals for 24 h with a mobile sensor platform supported by a cable infrastructure. We found that a first-order polynomial fit using piece-wise regression provided the most consistent estimation of the forest edge, relative to the visual edge, although we found no best sensing parameter as all measurements varied. Edge location estimates based on daytime net shortwave radiation had less difference from the visual edge than other shortwave measurements, but estimates made throughout the day with downward-facing or net infrared radiation sensors were more consistent and closer to the visual edge than any other measurement. This research contributes to the relatively small number of studies that have directly measured diurnal temporal and spatial patterns of microclimate variation across forest edges and demonstrates the use of a flexible mobile platform that enables repeated, high-resolution measurements of gradients of microclimate
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Moving from good to great: how one community college made the transition
The purpose of this study is to explore the applicability of Collins’ (2001) Good-to-Great theory, as originally introduced for the business sector and as adapted for the social sector, to the ways a community college moved from being “good” to being
“great.” The following questions guided the research: (1) Which of Collins’ themes, if any, were present for a community college that has transitioned from good to great in terms of organizational effectiveness? (2) What other themes, if any, were important for a community college moving from good to great? (3) What was the relative importance of Collins’ themes, among themselves and in relation to other important themes, for a community college moving from good to great? (4) How should Collins’ themes be altered to better describe their relevance in a community college moving from good to great? The research design included an interpretive social science methodology and
instrumental case study method at one college identified as having made the transition from good to great.
The findings demonstrated that elements from all seven of the Good-to-Great themes posited by Collins were present at the good-to-great community college, yet there were some features of the themes that were not present. A continuum of applicability for
Collins’ themes was presented with the Flywheel and Doom Loop theme having the greatest and the Hedgehog Concept having the least applicability to the community college context. Beyond the themes presented in Collins’ theory, three additional emergent themes contributed to the community college’s transition from good to great, specifically: (a) Context Matters, (b) Enduring Leadership, and (c) Creating the Reality We Need. Ascertaining the importance of Collins’ themes and the emergent themes in
relation to each other was found to be challenging and problematic as the interaction among all of the themes was seen as important. Alterations of all seven of Collins’ themes were proposed including: (a) Level 5 Leadership, (b) Both Who…And What, (c)Address the Uncomfortable Facts – And Never Lose Faith, (d) The Hedgehog Concept – Simplicity within the Three Circles, (e) A Culture of Disciplined Experimentation, (f) Technology Accelerators, and (g) The Flywheel and the Doom Loop. The study
concludes that, with increasing demand and accountability confronting community colleges in the face of reducing resources, the insights gained through the findings of a good-to-great college may provide helpful lessons for other community college leaders to consider when developing their own strategies for improving organizational effectiveness
Isolation of mutants of Escherichia coli lacking NAD- and NADP-linked malic enzyme activities
SummaryWhen Escherichia coli utilizes C4-dicarboxylic acids as sole sources of carbon and energy for growth, phosphoenolpyruvate is synthesized by means of phosphoenolpyruvate carboxykinase or by sequential action of malic enzyme and phosphoenolpyruvate synthetase. Chemical mutagenesis of a strain of E. coli K-12 lacking phosphoenolpyruvate carboxykinase activity yielded a mutant which grows very slowly on malate-mineral medium and lacks NAD-linked malic enzyme activity as well as phosphoenolpyruvate carboxykinase activity. A revertant of this double mutant which possesses elevated levels of NADP-linked malic enzyme activity grows well on malate-mineral medium. Further mutagenesis of this revertant produced a mutant which grows very slowly on malate-mineral medium and lacks NADP-linked malic enzyme activity as well as phosphoenolpyruvate carboxykinase and NAD-linked malic enzyme activities.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/22024/1/0000440.pd
The Role of the Radial Orbit Instability in Dark Matter Halo Formation and Structure
For a decade, N-body simulations have revealed a nearly universal dark matter
density profile, which appears to be robust to changes in the overall density
of the universe and the underlying power spectrum. Despite its universality,
the physical origin of this profile has not yet been well understood.
Semi--analytic models by Barnes et al. (2005) have suggested that the density
structure of dark matter halos is determined by the onset of the radial orbit
instability (ROI). We have tested this hypothesis using N-body simulations of
collapsing dark matter halos with a variety of initial conditions. For
dynamically cold initial conditions, the resulting halo structures are triaxial
in shape, due to the mild aspect of the instability. We examine how variations
in initial velocity dispersion affect the onset of the instability, and find
that an isotropic velocity dispersion can suppress the ROI entirely, while a
purely radial dispersion does not. The quantity sigma^2/vc^2 is a criterion for
instability, where regions with sigma^2/vc^2 <~1 become triaxial due to the ROI
or other perturbations. We also find that the radial orbit instability sets a
scale length at which the velocity dispersion changes rapidly from isotropic to
radially anisotropic. This scale length is proportional to the radius at which
the density profile changes shape, as is the case in the semi--analytic models;
however, the coefficient of proportionality is different by a factor of ~2.5.
We conclude that the radial orbit instability is likely to be a key physical
mechanism responsible for the nearly universal profiles of simulated dark
matter halos.Comment: 13 pages, 12 figures, accepted to Ap
Velocity Distributions from Nonextensive Thermodynamics
There is no accepted mechanism that explains the equilibrium structures that
form in collisionless cosmological N-body simulations. Recent work has
identified nonextensive thermodynamics as an innovative approach to the
problem. The distribution function that results from adopting this framework
has the same form as for polytropes, but the polytropic index is now related to
the degree of nonextensiveness. In particular, the nonextensive approach can
mimic the equilibrium structure of dark matter density profiles found in
simulations. We extend the investigation of this approach to the velocity
structures expected from nonextensive thermodynamics. We find that the
nonextensive and simulated N-body rms-velocity distributions do not match one
another. The nonextensive rms-velocity profile is either monotonically
decreasing or displays little radial variation, each of which disagrees with
the rms-velocity distributions seen in simulations. We conclude that the
currently discussed nonextensive models require further modifications in order
to corroborate dark matter halo simulations. (adapted from TeX)Comment: 3 color figures, accepted for publication in Ap
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