7,648 research outputs found
Micro-Irrigation Design For Avocado Orchard In California
This project encompasses the design and recommendations for a micro-irrigation system on an avocado orchard owned by Underwood Family Farms in Somis, California. The main objective of this report is to improve the existing irrigation system’s efficiency and uniformity with the new design and recommendations. The analysis includes information about good irrigation practices, irrigation system design and all the processes herein. Although there are many opinions on growing, irrigating and maintaining an avocado orchard, all of the methods, procedures and suggestions must be based on accurate data to provide reliable information to the grower. Evaluating the irrigation system and suggesting improvements will require proper steps and full understanding of irrigation systems, avocados, and soil and water requirements. This report will provide essential information for successfully growing avocados in Ventura County, as well as detailed advice for micro-irrigation systems on avocados
Pueblo Indian Water Rights: Struggle for a Precious Resource, by Charles T. DuMars, Marilyn O\u27Leary, and Albert E. Utton
Regional and Cellular Codistribution of Interleukin lß and Nerve Growth Factor rnRNA in the Adult Rat Brain
Avian photoreceptor patterns represent a disordered hyperuniform solution to a multiscale packing problem
Optimal spatial sampling of light rigorously requires that identical
photoreceptors be arranged in perfectly regular arrays in two dimensions.
Examples of such perfect arrays in nature include the compound eyes of insects
and the nearly crystalline photoreceptor patterns of some fish and reptiles.
Birds are highly visual animals with five different cone photoreceptor
subtypes, yet their photoreceptor patterns are not perfectly regular. By
analyzing the chicken cone photoreceptor system consisting of five different
cell types using a variety of sensitive microstructural descriptors, we find
that the disordered photoreceptor patterns are ``hyperuniform'' (exhibiting
vanishing infinite-wavelength density fluctuations), a property that had
heretofore been identified in a unique subset of physical systems, but had
never been observed in any living organism. Remarkably, the photoreceptor
patterns of both the total population and the individual cell types are
simultaneously hyperuniform. We term such patterns ``multi-hyperuniform''
because multiple distinct subsets of the overall point pattern are themselves
hyperuniform. We have devised a unique multiscale cell packing model in two
dimensions that suggests that photoreceptor types interact with both short- and
long-ranged repulsive forces and that the resultant competition between the
types gives rise to the aforementioned singular spatial features characterizing
the system, including multi-hyperuniformity.Comment: 31 pages, 12 figure
IN-SYNC. VIII. Primordial Disk Frequencies in NGC 1333, IC 348, and the Orion A Molecular Cloud
In this paper, we address two issues related to primordial disk evolution in
three clusters (NGC 1333, IC 348, and Orion A) observed by the INfrared Spectra
of Young Nebulous Clusters (IN-SYNC) project. First, in each cluster, averaged
over the spread of age, we investigate how disk lifetime is dependent on
stellar mass. The general relation in IC 348 and Orion A is that primordial
disks around intermediate mass stars (2--5) evolve faster than those
around loss mass stars (0.1--1), which is consistent with previous
results. However, considering only low mass stars, we do not find a significant
dependence of disk frequency on stellar mass. These results can help to better
constrain theories on gas giant planet formation timescales. Secondly, in the
Orion A molecular cloud, in the mass range of 0.35--0.7, we provide
the most robust evidence to date for disk evolution within a single cluster
exhibiting modest age spread. By using surface gravity as an age indicator and
employing 4.5 excess as a primordial disk diagnostic, we observe a
trend of decreasing disk frequency for older stars. The detection of
intra-cluster disk evolution in NGC 1333 and IC 348 is tentative, since the
slight decrease of disk frequency for older stars is a less than 1-
effect.Comment: 25 pages, 26 figures; submitted for publication (ApJ
Can Standing Long Jump Distance be Predicted from Standing Vertical Jump Distance?
Please view abstract in the attached PDF file
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