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Micrometre-scale refrigerators
A superconductor with a gap in the density of states or a quantum dot with
discrete energy levels is a central building block in realizing an electronic
on-chip cooler. They can work as energy filters, allowing only hot
quasiparticles to tunnel out from the electrode to be cooled. This principle
has been employed experimentally since the early 1990s in investigations and
demonstrations of micrometre-scale coolers at sub-kelvin temperatures. In this
paper, we review the basic experimental conditions in realizing the coolers and
the main practical issues that are known to limit their performance. We give an
update of experiments performed on cryogenic micrometre-scale coolers in the
past five years
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Crop competition studies : intercropping with groundnuts and estimation of competitive effects in corn.
SEQUENTIAL STOCHASTIC PRODUCTION DECISIONS FOR A PERENNIAL CROP: THE YIELD/QUALITY TRADEOFF FOR ALFALFA HAY
The "optimal cutting schedule" for alfalfa hay is described as a function of the trade-off between rising yield and falling quality of alfalfa over time and the local market prices being offered for different qualities of hay during the harvest season. Field test results quantify the yield/quality tradeoff for a California case study. A general decision rule is then derived to assist growers in making cutting decisions during a season. Finally, the optimal cutting schedule is shown to be the sum of sequential decisions for cuttings throughout the harvest season, with no schedule being best a priori.Crop Production/Industries,
Infinity
Prose by Eric Baugh. Finalist in the 2018 Manuscripts Prose Contest
Mrs. H. Bradley Putnam to Robert F. Kennedy (1 October 1962)
https://egrove.olemiss.edu/mercorr_pro/1300/thumbnail.jp
Joint assembly and genetic mapping of the Atlantic horseshoe crab genome reveals ancient whole genome duplication
Horseshoe crabs are marine arthropods with a fossil record extending back
approximately 450 million years. They exhibit remarkable morphological
stability over their long evolutionary history, retaining a number of ancestral
arthropod traits, and are often cited as examples of "living fossils." As
arthropods, they belong to the Ecdysozoa}, an ancient super-phylum whose
sequenced genomes (including insects and nematodes) have thus far shown more
divergence from the ancestral pattern of eumetazoan genome organization than
cnidarians, deuterostomes, and lophotrochozoans. However, much of ecdysozoan
diversity remains unrepresented in comparative genomic analyses. Here we use a
new strategy of combined de novo assembly and genetic mapping to examine the
chromosome-scale genome organization of the Atlantic horseshoe crab Limulus
polyphemus. We constructed a genetic linkage map of this 2.7 Gbp genome by
sequencing the nuclear DNA of 34 wild-collected, full-sibling embryos and their
parents at a mean redundancy of 1.1x per sample. The map includes 84,307
sequence markers and 5,775 candidate conserved protein coding genes. Comparison
to other metazoan genomes shows that the L. polyphemus genome preserves
ancestral bilaterian linkage groups, and that a common ancestor of modern
horseshoe crabs underwent one or more ancient whole genome duplications (WGDs)
~ 300 MYA, followed by extensive chromosome fusion
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