16,886 research outputs found
Trust in the US-EU fruit and vegetable chain: Do US exporters understand EU importers?
Research on organizational and inter organizational trust has become an important field in management and marketing literature, as it is perceived as a pivotal aspect of business transactions. However, clarifications are still needed on the issue of whom we trust; is the person whom we are trading with trusted, or the organization, or just the product‐quality? Not only has this question not been answered within this field of research, neither have cultural differences have been described to any great extent. Additionally, if the perceived factors important to establish trusting relationships may or may not be the same on the buyers and the sellers side in international business transaction in food chains. The primary objective of this research study therefore is to identify how well US exporters understand the elements of trust that establish strong relationships with EU importers. The Analytical Hierarchy Process was used to evaluate the importance of different trust elements in interviews conducted with US exporters and EU importers of fruits and vegetables. Results are compared, providing both a picture of the important facets of trust, as well as whether the partners understand the perspectives of the other partner
Why Campaigns for Local Transportation Initiatives Succeed or Fail: An Analysis of Four Communities and National Data, MTI Report 00-01
As funding from state and national sources has dwindled and demands for relief from traffic and congestion have grown, local governments and transportation agencies are increasingly left to develop their own sources of enhanced revenues. Frequently the bid to increase available revenues comprises a local ballot measure, enabling the citizens served by these governments and agencies to express their preferences for or against increased taxation in support of an improved transportation system. What determines the success of campaigns in support of such ballot measures? To answer this question, this report includes the use of two different approaches and data sources. 1) A statistical analysis of community-level characteristics. Data from localities across the nation, as well those within the state of California, that have conducted elections for transportation tax increase are analyzed to determine what factors seem to affect the outcome of such elections. 2) Case studies of four communities that recently conducted elections for transportation tax increases (Santa Clara and Sonoma Counties in California, and the Denver and Seattle metropolitan areas). The case studies allow for in-depth, qualitative understanding of what election strategies and other campaign elements comprise successful or unsuccessful efforts to raise local revenues. Among the most significant findings from the statistical analysis of local elections were the following: Efforts to fund transportation with taxes where the proportion of elderly is greater than 9 percent are more likely to succeed In communities where the percentage of elderly is greater than 9 percent, the analysis indicates that voters may be more willing to accept local transportation taxes. However, in communities where the percentage of elderly is less than 9 percent, transportation measures may require significantly more determined marketing to enhance the probability of passage. Efforts to increase sales taxes for transportation programs will be less successful in communities with higher sales taxes. A relatively strong and negative relationship between sales tax and support for transportation tax initiatives was identified in the national election data. This suggests that communities with relatively higher sales taxes will be hard pressed to convince citizens to support additional increases
Interplay of screening and superconductivity in low-dimensional materials
A quantitative description of Coulomb interactions is developed for
two-dimensional superconducting materials, enabling us to compare intrinsic
with external screening effects, such as those due to substrates. Using the
example of a doped monolayer of MoS2 embedded in a tunable dielectric
environment, we demonstrate that the influence of external screening is limited
to a length scale, bounded from below by the effective thickness of the
quasi-two-dimensional material and from above by its intrinsic screening
length. As a consequence, it is found that unconventional Coulomb-driven
superconductivity cannot be induced in MoS2 by tuning the substrate properties
alone. Our calculations of the retarded Morel-Anderson Coulomb potential {\mu
*} reveal that the Coulomb interactions, renormalized by the reduced layer
thickness and the substrate properties, can shift the onset of the
electron-phonon driven superconducting phase in monolayer MoS2 but do not
significantly affect the critical temperature at optimal doping.Comment: 8 pages, 5 figure
Mechanism of T-Cell Lymphomagenesis: Transformation of Growth-Factor-Dependent T-Lymphoblastoma Cells to Growth-Factor-Independent T-Lymphoma Cells
In a previous paper we described the induction by x-irradiation or radiation-induced leukemia virus-in-oculation of two classes of lymphoid T-cell neoplasms: The first class, designated T-cell lymphoblastoma (TCLB), consists of growth-factor-dependent eudiploid cells that home to the spleen and give rise to splenic tumors on injection into syngeneic mice; the second class, designated T-cell lymphoma (TCL), consists of growth-factor-independent aneuploid or pseudodiploid cells that give rise to local tumors at the site of subcutaneous injection. This paper describes the generation of a family of growth-factor-independent aneuploid or pseudodiploid TCL cells after the injection into the thymus of growth-factor-dependent diploid TCLB cells. In contrast to the donor TCLB cells, the resulting TCL cells could be cloned in semisolid medium, produced local tumors at the site of subcutaneous injection, and proliferated in a growth-factor-independent fashion in vitro. The induced growth-factor-independent TCL cells were chromosomally and phenotypically unstable and continued to evolve both in vivo and in vitro. After propagation in the thymus, the cells often showed stable translocations in addition to the evolving aneuploidy. We propose that the chromosome abnormalities induced during the proliferation of growth-factor-dependent TCLB cells in the thymus constitute a general mechanism by which neoplastic cells progress from growth-factor dependency to independency
The disordered-free-moment phase: a low-field disordered state in spin-gap antiferromagnets with site dilution
Site dilution of spin-gapped antiferromagnets leads to localized free
moments, which can order antiferromagnetically in two and higher dimensions.
Here we show how a weak magnetic field drives this order-by-disorder state into
a novel disordered-free-moment phase, characterized by the formation of local
singlets between neighboring moments and by localized moments aligned
antiparallel to the field. This disordered phase is characterized by the
absence of a gap, as it is the case in a Bose glass. The associated
field-driven quantum phase transition is consistent with the universality of a
superfluid-to-Bose-glass transition. The robustness of the
disordered-free-moment phase and its prominent features, in particular a series
of pseudo-plateaus in the magnetization curve, makes it accessible and relevant
to experiments.Comment: 4 pages, 4 figure
Single hole dynamics in dimerized spin liquids
The dynamics of a single hole in quantum antiferromagnets is influenced by
magnetic fluctuations. In the present work we consider two situations. The
first one corresponds to a single hole in the two leg t-J spin ladder. In this
case the wave function renormalization is relatively small and the
quasiparticle residue of the S=1/2 state remains close to unity. However at
large t/J there are higher spin (S=3/2,5/2,..) bound states of the hole with
the magnetic excitations, and therefore there is a crossover from
quasiparticles with S=1/2 to quasiparticles with higher spin.
The second situation corresponds to a single hole in two coupled
antiferromagnetic planes very close to the point of antiferromagnetic
instability. In this case the hole wave function renormalization is very strong
and the quasiparticle residue vanishes at the point of instability.Comment: 12 pages, 3 figure
Maximizing Maximal Angles for Plane Straight-Line Graphs
Let be a plane straight-line graph on a finite point set
in general position. The incident angles of a vertex
of are the angles between any two edges of that appear consecutively in
the circular order of the edges incident to .
A plane straight-line graph is called -open if each vertex has an
incident angle of size at least . In this paper we study the following
type of question: What is the maximum angle such that for any finite set
of points in general position we can find a graph from a certain
class of graphs on that is -open? In particular, we consider the
classes of triangulations, spanning trees, and paths on and give tight
bounds in most cases.Comment: 15 pages, 14 figures. Apart of minor corrections, some proofs that
were omitted in the previous version are now include
Near Infrared Adaptive Optics Imaging of QSO Host Galaxies
We report near-infrared (primarily H-band) adaptive optics (AO) imaging with
the Gemini-N and Subaru Telescopes, of a representative sample of 32 nearby
(z<0.3) QSOs selected from the Palomar-Green (PG) Bright Quasar Survey (BQS),
in order to investigate the properties of the host galaxies. 2D modeling and
visual inspection of the images shows that ~36% of the hosts are ellipticals,
\~39% contain a prominent disk component, and ~25% are of undetermined type.
30% show obvious signs of disturbance. The mean M_H(host) = -24.82 (2.1L_H*),
with a range -23.5 to -26.5 (~0.63 to 10 L_H*). At <L_H*, all hosts have a
dominant disk component, while at >2 L_H* most are ellipticals. "Disturbed"
hosts are found at all M_H(host), while "strongly disturbed" hosts appear to
favor the more luminous hosts. Hosts with prominent disks have less luminous
QSOs, while the most luminous QSOs are almost exclusively in ellipticals or in
mergers (which presumably shortly will be ellipticals). At z<0.13, where our
sample is complete at B-band, we find no clear correlation between M_B(QSO) and
M_H(host). However, at z>0.15, the more luminous QSOs (M_B<-24.7), and 4/5 of
the radio-loud QSOs, have the most luminous H-band hosts (>7L_H*), most of
which are ellipticals. Finally, we find a strong correlation between the
"infrared-excess", L_IR/L_BB, of QSOs with host type and degree of disturbance.
Disturbed and strongly disturbed hosts and hosts with dominant disks have
L_IR/L_BB twice that of non-disturbed and elliptical hosts, respectively. QSOs
with "disturbed" and "strongly-disturbed" hosts are also found to have
morphologies and mid/far-infrared colors that are similar to what is found for
"warm" ultraluminous infrared galaxies, providing further evidence for a
possible evolutionary connection between both classes of objects.Comment: 80 pages, accepted for publication in ApJ Supp
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