32,527 research outputs found
Young Member Programs for Cooperatives
The overall objective of this study is to provide cooperative decision makers with effective strategies for developing young member programs in local cooperatives. To accomplish this, the study sets out to determine: (1) the range and scope of young member programs and activities utilized by a sample of local cooperatives, (2) the relationship of young member programs and activities to the legislative system of local cooperatives, (3) the factors that block integration of young member programs and activities into local cooperatives and (4) the organizing procedures that help stimulate the development of young member programs and activities.Cooperative, young member, education, program, participation, Agribusiness,
Subroutines GEORGE and DRASTC simplify operation of automatic digital plotter
FORTRAN language subroutines enable the production of a tape for a 360-30 tape unit that controls the CALCOMP 566 Digital Incremental Plotter. This provides the plotter with instructions for graphically displaying data points with the proper scaling of axes, numbering, lettering, and tic marking
Boiler for generating high quality vapor
Boiler supplies vapor for use in turbines by imparting a high angular velocity to the liquid annulus in heated rotating drum. Drum boiler provides a sharp interface between boiling liquid and vapor, thereby, inhibiting the formation of unwanted liquid droplets
Orbital control in strained ultra-thin LaNiO/LaAlO superlattices
In pursuit of rational control of orbital polarization, we present a combined
experimental and theoretical study of single unit cell superlattices of the
correlated metal LaNiO and the band insulator LaAlO. Polarized x-ray
absorption spectra show a distinct asymmetry in the orbital response under
strain. A splitting of orbital energies consistent with octahedral distortions
is found for the case of compressive strain. In sharp contrast, for tensile
strain, no splitting is found although a strong orbital polarization is
present. Density functional theory calculations including a Hubbard U term
reveal that this asymmetry is a result of the interplay of strain and
confinement induces octahedral rotations and distortions and altered covalency
in the bonding across the interfacial Ni-O-Al apical oxygen, leading to a
charge disporportionation at the Ni sites for tensile strain.Comment: 4 pages. 5 figure
Strain-mediated metal-insulator transition in epitaxial ultra-thin films of NdNiO3
We have synthesized epitaxial NdNiO ultra-thin films in a
layer-by-layer growth mode under tensile and compressive strain on SrTiO
(001) and LaAlO (001), respectively. A combination of X-ray diffraction,
temperature dependent resistivity, and soft X-ray absorption spectroscopy has
been applied to elucidate electronic and structural properties of the samples.
In contrast to the bulk NdNiO, the metal-insulator transition under
compressive strain is found to be completely quenched, while the transition
remains under the tensile strain albeit modified from the bulk behavior.Comment: 4 pages, 4 figure
Diversity in the organization of elastin bundles and intramembranous muscles in bat wings
Unlike birds and insects, bats fly with wings composed of thin skin that envelops the bones of the forelimb and spans the area between the limbs, digits, and sometimes the tail. This skin is complex and unusual; it is thinner than typical mammalian skin and contains organized bundles of elastin and embedded skeletal muscles. These elements are likely responsible for controlling the shape of the wing during flight and contributing to the aerodynamic capabilities of bats. We examined the arrangement of two macroscopic architectural elements in bat wings, elastin bundles and wing membrane muscles, to assess the diversity in bat wing skin morphology. We characterized the plagiopatagium and dactylopatagium of 130 species from 17 families of bats using cross‐polarized light imaging. This method revealed structures with distinctive relative birefringence, heterogeneity of birefringence, variation in size, and degree of branching. We used previously published anatomical studies and tissue histology to identify birefringent structures, and we analyzed their architecture across taxa. Elastin bundles, muscles, neurovasculature, and collagenous fibers are present in all species. Elastin bundles are oriented in a predominantly spanwise or proximodistal direction, and there are five characteristic muscle arrays that occur within the plagiopatagium, far more muscle than typically recognized. These results inform recent functional studies of wing membrane architecture, support the functional hypothesis that elastin bundles aid wing folding and unfolding, and further suggest that all bats may use these architectural elements for flight. All species also possess numerous muscles within the wing membrane, but the architecture of muscle arrays within the plagiopatagium varies among families. To facilitate present and future discussion of these muscle arrays, we refine wing membrane muscle nomenclature in a manner that reflects this morphological diversity. The architecture of the constituents of the skin of the wing likely plays a key role in shaping wings during flight
Effect of polar discontinuity on the growth of LaNiO3/LaAlO3 superlattices
We have conducted a detailed microscopic investigation of [LaNiO3(1
u.c.)/LaAlO3(1 u.c.)]N superlattices grown on (001) SrTiO3 and LaAlO3 to
explore the influence of polar mismatch on the resulting electronic and
structural properties. Our data demonstrate that the initial growth on the
non-polar SrTiO3 surface leads to a rough morphology and unusual 2+ valence of
Ni in the first LaNiO3 layer, which is not observed after growth on the polar
surface of LaAlO3. A newly devised model suggests that the polar mismatch can
be resolved if the perovskite layers grow with an excess of LaO, which also
accounts for the observed electronic, chemical, and structural effects.Comment: 3 pages, 3 figure
Structure of a liquid crystalline fluid around a macroparticle: Density functional theory study
The structure of a molecular liquid, in both the nematic liquid crystalline
and isotropic phases, around a cylindrical macroparticle, is studied using
density functional theory. In the nematic phase the structure of the fluid is
highly anisotropic with respect to the director, in agreement with results from
simulation and phenomenological theories. On going into the isotropic phase the
structure becomes rotationally invariant around the macroparticle with an
oriented layer at the surface.Comment: 10 pages, 6 figues. Submitted to Phys. Rev.
Modelling bacterial behaviour close to a no-slip plane boundary: the influence of bacterial geometry
We describe a boundary-element method used to model the hydrodynamics of a bacterium propelled by a single helical flagellum. Using this model, we optimize the power efficiency of swimming with respect to cell body and flagellum geometrical parameters, and find that optima for swimming in unbounded fluid and near a no-slip plane boundary are nearly indistinguishable. We also consider the novel optimization objective of torque efficiency and find a very different optimal shape. Excluding effects such as Brownian motion and electrostatic interactions, it is demonstrated that hydrodynamic forces may trap the bacterium in a stable, circular orbit near the boundary, leading to the empirically observable surface accumulation of bacteria. Furthermore, the details and even the existence of this stable orbit depend on geometrical parameters of the bacterium, as described in this article. These results shed some light on the phenomenon of surface accumulation of micro-organisms and offer hydrodynamic explanations as to why some bacteria may accumulate more readily than others based on morphology
Local Electronic and Magnetic Studies of an Artificial La2FeCrO6 Double Perovskite
Through the utilization of element-resolved polarized x-ray probes, the
electronic and magnetic state of an artificial La2FeCrO6 double perovskite were
explored. Applying unit-cell level control of thin film growth on SrTiO3 (111),
the rock salt double perovskite structure can be created for this system, which
does not have an ordered perovskite phase in the bulk. We find that the Fe and
Cr are in the proper 3+ valence state, but, contrary to previous studies, the
element-resolved magnetic studies find the moments in field are small and show
no evidence of a sizable magnetic moment in the remanent state.Comment: 3 pages, 4 figure
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