1,204 research outputs found
Centrally symmetric polytopes with many faces
We present explicit constructions of centrally symmetric polytopes with many
faces: first, we construct a d-dimensional centrally symmetric polytope P with
about (1.316)^d vertices such that every pair of non-antipodal vertices of P
spans an edge of P, second, for an integer k>1, we construct a d-dimensional
centrally symmetric polytope P of an arbitrarily high dimension d and with an
arbitrarily large number N of vertices such that for some 0 < delta_k < 1 at
least (1-delta_k^d) {N choose k} k-subsets of the set of vertices span faces of
P, and third, for an integer k>1 and a>0, we construct a centrally symmetric
polytope Q with an arbitrary large number N of vertices and of dimension
d=k^{1+o(1)} such that least (1 - k^{-a}){N choose k} k-subsets of the set of
vertices span faces of Q.Comment: 14 pages, some minor improvement
Neighborliness of the symmetric moment curve
We consider the convex hull B_k of the symmetric moment curve U(t)=(cos t,
sin t, cos 3t, sin 3t, ..., cos (2k-1)t, sin (2k-1)t) in R^{2k}, where t ranges
over the unit circle S= R/2pi Z. The curve U(t) is locally neighborly: as long
as t_1, ..., t_k lie in an open arc of S of a certain length phi_k>0, the
convex hull of the points U(t_1), ..., U(t_k) is a face of B_k. We characterize
the maximum possible length phi_k, proving, in particular, that phi_k > pi/2
for all k and that the limit of phi_k is pi/2 as k grows. This allows us to
construct centrally symmetric polytopes with a record number of faces.Comment: 28 pages, proofs are simplified and results are strengthened somewha
Customer perceived value—Conceptualization and avenues for future research
Given the present dynamic consumption environment due to technological innovations as well as interlinked economic developments on the macro-, micro-, and societal-level, researchers and managers have been increasingly showing interest in the concept of customer perceived value. However, especially given its vast empirical application, surprisingly little effort has been paid to synthesize various perspectives on the dimensionality, abstraction, and model taxonomy of customer perceived value. Therefore, based on a comprehensive literature review, this article identifies the predominant conceptualization of customer perceived value, thus also providing a sound basis for future empirical assessments of this concept, and discusses avenues for future research. In addition to contributing to research, this study also contributes to practice by comprehensively positioning customer perceived value as a key source of competitive advantage in the context of relationship marketing, management, and business models
Exploring AGN Activity over Cosmic Time with the SKA
In this Chapter we present the motivation for undertaking both a wide and
deep survey with the SKA in the context of studying AGN activity across cosmic
time. With an rms down to 1 Jy/beam at 1 GHz over 1,000 - 5,000 deg in
1 year (wide tier band 1/2) and an rms down to 200 nJy/beam over 10 - 30
deg in 2000 hours (deep tier band 1/2), these surveys will directly detect
faint radio-loud and radio-quiet AGN (down to a 1 GHz radio luminosity of about
W/Hz at ). For the first time, this will enable us to
conduct detailed studies of the cosmic evolution of radio AGN activity to the
cosmic dawn (), covering all environmental densities.Comment: 17 pages, 7 figures, to appear as part of 'Continuum Science' in
Proceedings 'Advancing Astrophysics with the SKA (AASKA14)
Probing the Tavis-Cummings level splitting with intermediate-scale superconducting circuits
We demonstrate the local control of up to eight two-level systems interacting
strongly with a microwave cavity. Following calibration, the frequency of each
individual two-level system (qubit) is tunable without influencing the others.
Bringing the qubits one by one on resonance with the cavity, we observe the
collective coupling strength of the qubit ensemble. The splitting scales up
with the square root of the number of the qubits, which is the hallmark of the
Tavis-Cummings model. The local control circuitry causes a bypass shunting the
resonator, and a Fano interference in the microwave readout, whose contribution
can be calibrated away to recover the pure cavity spectrum. The simulator's
attainable size of dressed states with up to five qubits is limited by reduced
signal visibility, and -- if uncalibrated -- by off-resonance shifts of
sub-components. Our work demonstrates control and readout of quantum coherent
mesoscopic multi-qubit system of intermediate scale under conditions of noise
Validation of a Diagnostic Marker for Primocane-Fruiting in Blackberry
Typical blackberries (Rubus subgenus Rubus) have perennial crowns and roots and biennial canes. The first-year canes (primocanes) are usually vegetative, while second-year canes (floricanes) produce fruit. Primocane-fruiting blackberries produce fruit on first-year canes and are desirable to growers because they potentially allow for a longer harvest season in temperate regions and enable production in tropical areas where no natural chill hours are accumulated. The development of molecular markers for desirable traits can potentially increase efficiency in blackberry breeding. However, to date, there are no diagnostic molecular markers for economically important traits in blackberries. Primocane-fruiting is recessively inherited, and tetraploid blackberries must have four copies of the primocane allele for the trait to be expressed. A single locus strongly associated with primocane fruiting was recently identified on chromosome Ra03, and a new KASP marker (PF2) was developed within this locus. In this study, we validated the performance of the new PF2 marker in a seedling population (Population 1937) segregating for primocane-fruiting at the University of Arkansas System Division of Agriculture\u27s Fruit Breeding Program. In 2022, 170 seedlings in the population were evaluated for primocane-fruiting. Of these seedlings, 68 were floricane-fruiting, 86 were primocane-fruiting, and 16 could not be phenotyped due to poor plant growth. The PF2 marker correctly predicted the phenotype for 146 of 154 progeny that were scored in the 1937 population. Some of the inconsistencies between the marker prediction and the observed phenotypes could have been due to weak plants shaded out by neighbors or human error
Ă–konomische Effekte der Vereinigten BĂĽhnen Wien
aus dem Inhaltsverzeichnis: Einleitung; Kultur und Tourismus - ökonomische Aspekte; Untersuchungsmethode; Ökonomische Effekte der Ausgaben der Vereinigten Bühnen Wien; Ökonomische Effekte der Ausgaben der BesucherInnen der Vereinigten Bühnen Wien; Executive Summary; Literaturverzeichnis
Validation of a Diagnostic Marker for Primocane-Fruiting in Blackberry
Typical blackberries (Rubus subgenus Rubus) have perennial crowns and roots and biennial canes. The first-year canes (primocanes) are usually vegetative, while second-year canes (floricanes) produce fruit. Primocane-fruiting blackberries produce fruit on first-year canes and are desirable to growers because they potentially allow for a longer harvest season in temperate regions and enable production in tropical areas where no natural chill hours are accumulated. The development of molecular markers for desirable traits can potentially increase efficiency in blackberry breeding. However, to date, there are no diagnostic molecular markers for economically important traits in blackberries. Primocane-fruiting is recessively inherited, and tetraploid blackberries must have four copies of the primocane allele for the trait to be expressed. A single locus strongly associated with primocane fruiting was recently identified on chromosome Ra03, and a new KASP marker (PF2) was developed within this locus. In this study, we validated the performance of the new PF2 marker in a seedling population (Population 1937) segregating for primocane-fruiting at the University of Arkansas System Division of Agriculture\u27s Fruit Breeding Program. In 2022, 170 seedlings in the population were evaluated for primocane-fruiting. Of these seedlings, 68 were floricane-fruiting, 86 were primocane-fruiting, and 16 could not be phenotyped due to poor plant growth. The PF2 marker correctly predicted the phenotype for 146 of 154 progeny that were scored in the 1937 population. Some of the inconsistencies between the marker prediction and the observed phenotypes could have been due to weak plants shaded out by neighbors or human error
Population Inversion in Monolayer and Bilayer Graphene
The recent demonstration of saturable absorption and negative optical
conductivity in the Terahertz range in graphene has opened up new opportunities
for optoelectronic applications based on this and other low dimensional
materials. Recently, population inversion across the Dirac point has been
observed directly by time- and angle-resolved photoemission spectroscopy
(tr-ARPES), revealing a relaxation time of only ~ 130 femtoseconds. This
severely limits the applicability of single layer graphene to, for example,
Terahertz light amplification. Here we use tr-ARPES to demonstrate long-lived
population inversion in bilayer graphene. The effect is attributed to the small
band gap found in this compound. We propose a microscopic model for these
observations and speculate that an enhancement of both the pump photon energy
and the pump fluence may further increase this lifetime.Comment: 18 pages, 6 figure
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