3,848 research outputs found
Walla Walla Valley Viticultural Area
Produced by the Walla Walla Valley Wine Alliance, this map depicts the Walla Walla Valley AVA (American Viticultural Area), which crosses state boundaries. The Walla Walla Valley AVA extends from Southern Washington to Northern Oregon
The entangling and disentangling power of unitary transformations are unequal
We consider two capacity quantities associated with bipartite unitary gates:
the entangling and the disentangling power. For two-qubit unitaries these two
capacities are always the same. Here we prove that these capacities are
different in general. We do so by constructing an explicit example of a
qubit-qutrit unitary whose entangling power is maximal (2 ebits), but whose
disentangling power is strictly less. A corollary is that there can be no
unique ordering for unitary gates in terms of their ability to perform
non-local tasks. Finally we show that in large dimensions, almost all bipartite
unitaries have entangling and disentangling capacities close to the maximal
possible (and thus in high dimensions the difference in these capacities is
small for almost all unitaries).Comment: 6 pages, 1 airfoi
Theoretically palatable flavor combinations of astrophysical neutrinos
The flavor composition of high-energy astrophysical neutrinos can reveal the
physics governing their production, propagation, and interaction. The IceCube
Collaboration has published the first experimental determination of the ratio
of the flux in each flavor to the total. We present, as a theoretical
counterpart, new results for the allowed ranges of flavor ratios at Earth for
arbitrary flavor ratios in the sources. Our results will allow IceCube to more
quickly identify when their data imply standard physics, a general class of new
physics with arbitrary (incoherent) combinations of mass eigenstates, or new
physics that goes beyond that, e.g., with terms that dominate the Hamiltonian
at high energy.Comment: 13 pages, 12 figures. Matches published versio
The quantum capacity with symmetric side channels
We present an upper bound for the quantum channel capacity that is both
additive and convex. Our bound can be interpreted as the capacity of a channel
for high-fidelity quantum communication when assisted by a family of channels
that have no capacity on their own. This family of assistance channels, which
we call symmetric side channels, consists of all channels mapping symmetrically
to their output and environment. The bound seems to be quite tight, and for
degradable quantum channels it coincides with the unassisted channel capacity.
Using this symmetric side channel capacity, we find new upper bounds on the
capacity of the depolarizing channel. We also briefly indicate an analogous
notion for distilling entanglement using the same class of (one-way) channels,
yielding one of the few entanglement measures that is monotonic under local
operations with one-way classical communication (1-LOCC), but not under the
more general class of local operations with classical communication (LOCC).Comment: 10 pages, 4 figure
ESTIMATION OF WHEAT ACREAGE RESPONSE FUNCTIONS FOR THE NORTHWEST
Acreage response functions for wheat are fitted to aggregate data and pooled time-series and cross-sectional data for the Northwest. It was hypothesized that the pooled data approach provides a useful alternative to using aggregate data since it requires fewer timer-series observations for reliable parameter estimation and it does not require the assumption of constant acreage response elasticities throughout the region. The results of this study verify this hypothesis as well as indicate that regional response elasticities for Northwest wheat acreage may differ greatly from national estimates.Crop Production/Industries,
Macroeconomic Adjustment and Foreign Trade of Centrally Planned Economies
This empirical study stresses the underlying macroeconomic forces which determine foreign trade flows in CPEs. The general specification includes a planners' demand equation for the volume of imports, a planners' supply equation for the volume of exports, and a rest-of-world demand equation for the export price level. The planners' behavioural equations include variables for activity levels, trade balance constraints, prices, and domestic excess demand. The import price is exogenous. This simultaneous equation model is estimated on annual data from the mid-1950s to the mid-1970s, for Czechoslovakia, the GDR, Hungary, and Poland. Maximum likelihood estimation in a nested hypothesis testing framework allows selection of restricted versions of the general model for each country. Estimated price elasticities accord with the underlying theory, and the excess demand variables perform well.
Detection of long-range dependence in peak ground reaction forces during running using ARFIMA modelling
Coronary heart disease and hydrogenated fat; an investigation of the levels of chemically-modified fats on adipose tissue
Ultra-long-term follow-up of pediatric spinal deformity problems: 23 patients with a mean follow-up of 51 years
AbstractBackground.The aim of this study was to analyze the true outcomes of a unique cohort of patients with spinal deformities who were treated as children and followed for 40 or more years.Methods.Altogether, 23 patients were reviewed who had been originally treated in our community, whose original charts and radiographs were still available, and who had undergone recent evaluation.Results.The diagnoses were congenital deformity in eight, adolescent idiopathic scoliosis in four, poliomyelitis in three, infantile idiopathic scoliosis in two, spondylolisthesis in two, and one each of tuberculosis and dwarfism. Sixteen had undergone fusion surgery.Conclusions.Early spine fusion for deformity produced far better results than delayed fusion. A solid fusion at the end of growth remained unchanged. Degenerative changes outside the fusion area were rare and seldom required further surgery. In summary, 23 patients with a mean follow-up of 51 years after treatment are presented. Early fusion was far superior to delayed or nonsurgical treatment
Homogeneous rhodium catalysed hydrocarbonylation reactions of alkenes
The conversion of ethene, carbon monoxide and water to propanoic acid by the catalytic action of various rhodium species, was investigated by infra-red spectroscopy and autoclave batch reactions. Utilisation of a high pressure infra-red cell and a Fourier Transform infra-red spectrometry enabled study of the spectra of the catalytic systems at temperatures up to 180ÂşC, and at pressures of 10 -150 bar. The batch autoclave reactions enable rates, yield and selectivities to be determined with the aid of Gas Chromatography and Mass Spectroscopy. Rhodium halides were used as precursors and the effects of solvents, water, iodide initiators, were studied. It was shown that polar solvents favoured hydrocarbonylation as did hydrous conditions. Ethyl iodide and hydrogen iodide were active initiators, however hydrogen iodide was observed to poison the catalyst forming [Rh(CO)(_2)I(_4)](^-) and other rhodium(III) species. At temperatures above 170ÂşC rhodium(I) species such as [Rh(CO)(_2)I(_2)](^-) were more prominent. A novel catalyst system was produced by employing rhodium(III) chloride, tin(II) chloride and hydrochloric acid. The nature of this system was studied in terms of solvents, the interaction of rhodium and tin, and the role of hydrogen chloride. Infrared studies revealed rhodium-tin species in the reaction media. Studies were conducted to ascertain the role of cations and additives. Further studies determined the activity of other metals as co-catalysts to rhodium, showing tin to be a superior co-catalyst
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