694 research outputs found
'Puma' Grapefruit
'Puma' is a high quality, productive citrus
hybrid resulting from a cross between pummelo
and grapefuit (C. grandis x C. paradisi L.). The cross was made and resulting hybrid seedlings grown by the Department of Horticulture, University of Hawaii
Reconfiguration on sparse graphs
A vertex-subset graph problem Q defines which subsets of the vertices of an
input graph are feasible solutions. A reconfiguration variant of a
vertex-subset problem asks, given two feasible solutions S and T of size k,
whether it is possible to transform S into T by a sequence of vertex additions
and deletions such that each intermediate set is also a feasible solution of
size bounded by k. We study reconfiguration variants of two classical
vertex-subset problems, namely Independent Set and Dominating Set. We denote
the former by ISR and the latter by DSR. Both ISR and DSR are PSPACE-complete
on graphs of bounded bandwidth and W[1]-hard parameterized by k on general
graphs. We show that ISR is fixed-parameter tractable parameterized by k when
the input graph is of bounded degeneracy or nowhere-dense. As a corollary, we
answer positively an open question concerning the parameterized complexity of
the problem on graphs of bounded treewidth. Moreover, our techniques generalize
recent results showing that ISR is fixed-parameter tractable on planar graphs
and graphs of bounded degree. For DSR, we show the problem fixed-parameter
tractable parameterized by k when the input graph does not contain large
bicliques, a class of graphs which includes graphs of bounded degeneracy and
nowhere-dense graphs
'Kaimana', an improved new lychee cultivar for Hawaii
Lychee (Litchi chinensis L.) 'Kaimana' was named in 1982 to commemorate the 75th ("diamond") anniversary of the establishment of the Hawaii Agricultural Experiment Station. 'Kaimana' means "diamond" in the Hawaiian language. The original seedling tree of 'Kaimana' grown at the Poamoho experimental farm on Oahu first produced fruit in 1965 at 10 years of age. This is truly a jewel of a lychee, producing excellent quality fruit. In addition, it has a more consistent bearing habit than any of the 14 Chinese lychee cultivars imported and tested in Hawaii during the past 110 years
Macadamia: Hawaii's Dessert Nut
This publication on macadamia nuts in Hawaii covers botany, cultivars, orchard establishment, fertilization, diseases and pests, and harvesting and processing
Herbicide evaluation studies with celery (Apium graveolens var. dulce), lettuce (Lactuca sativa), and crucifers (Brassica spp.) in Hawaii
Optimized coupling of cold atoms into a fiber using a blue-detuned hollow-beam funnel
We theoretically investigate the process of coupling cold atoms into the core
of a hollow-core photonic-crystal optical fiber using a blue-detuned
Laguerre-Gaussian beam. In contrast to the use of a red-detuned Gaussian beam
to couple the atoms, the blue-detuned hollow-beam can confine cold atoms to the
darkest regions of the beam thereby minimizing shifts in the internal states
and making the guide highly robust to heating effects. This single optical beam
is used as both a funnel and guide to maximize the number of atoms into the
fiber. In the proposed experiment, Rb atoms are loaded into a magneto-optical
trap (MOT) above a vertically-oriented optical fiber. We observe a
gravito-optical trapping effect for atoms with high orbital momentum around the
trap axis, which prevents atoms from coupling to the fiber: these atoms lack
the kinetic energy to escape the potential and are thus trapped in the laser
funnel indefinitely. We find that by reducing the dipolar force to the point at
which the trapping effect just vanishes, it is possible to optimize the
coupling of atoms into the fiber. Our simulations predict that by using a
low-power (2.5 mW) and far-detuned (300 GHz) Laguerre-Gaussian beam with a
20-{\mu}m radius core hollow-fiber it is possible to couple 11% of the atoms
from a MOT 9 mm away from the fiber. When MOT is positioned further away,
coupling efficiencies over 50% can be achieved with larger core fibers.Comment: 11 pages, 12 figures, 1 tabl
Predictions for the correlation between giant and terrestrial extrasolar planets in dynamically evolved systems
The large eccentricities of many giant extrasolar planets may represent the
endpoint of gravitational scattering in initially more crowded systems. If so,
the early evolution of the giant planets is likely to be more restrictive of
terrestrial planet formation than would be inferred from the current,
dynamically quiescent, configurations. Here, we study statistically the extent
of the anti-correlation between giant planets and terrestrial planets expected
in a scattering model. We use marginally stable systems of three giant planets,
with a realistic range of planetary masses, as a simple model for the initial
conditions prior to scattering, and show that after scattering the surviving
planets reproduce well the known extrasolar planet eccentricities beyond a >
0.5 AU. By tracking the minimum periastron values of all planets during the
evolution, we derive the distribution of orbital radii across which strong
perturbations (from crossing orbits) are likely to affect low mass planet
formation. We find that scattering affects inner planet formation at orbital
separations less than 50% of the final periastron distance of the innermost
massive planet in approximately 30% of the realizations, and can occasionally
influence planet formation at orbital separations less than 20% of the final
periastron distance of the innermost massive planet. The domain of influence of
the scattering massive planets increases as the mass differential between the
massive planets decreases. Observational study of the correlation between
massive and terrestrial extrasolar planets in the same system has the potential
to constrain the origin of planetary eccentricity.Comment: 8 pages, 8 figures, 1 table, accepted for publication in Ap
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