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The Human Brain: A Multimedia Tutorial For The Independent Learner
The Human Brain is a multimedia, interactive, computer-based tutorial on the structure and function of the human nervous system. In creating it, we aim to solve a number of problems, both subject specific and general. As a subject, the structure and function of the nervous system is difficult to teach using traditional methods and there is a lack of integration in the teaching of structure and function. More generally, we are concerned with the difficulties of both assessing student understanding of a particular subject and remedying any deficiencies when the student is learning independently. Finally, we hope to resolve the conflict between linear and explorative modes of presentation of material in a teaching system
Recirculation effects produced by a pair of heated jets impinging on a ground plane
Exhaust recirculation effects produced by two heated jets impinging on ground plan
Cartilage on the Move: Cartilage Lineage Tracing During Tadpole Metamorphosis
The reorganization of cranial cartilages during tadpole metamorphosis is a set of complex processes. The fates of larval cartilage-forming cells (chondrocytes) and sources of adult chondrocytes are largely unknown. Individual larval cranial cartilages may either degenerate or remodel, while many adult cartilages appear to form de novo during metamorphosis. Determining the extent to which adult chondrocytes/cartilages are derived from larval chondrocytes during metamorphosis requires new techniques in chondrocyte lineage tracing. We have developed two transgenic systems to label cartilage cells throughout the body with fluorescent proteins. One system strongly labels early tadpole cartilages only. The other system inducibly labels forming cartilages at any developmental stage. We examined cartilages of the skull (viscero- and neurocranium), and identified larval cartilages that either resorb or remodel into adult cartilages. Our data show that the adult otic capsules, tecti anterius and posterius, hyale, and portions of Meckel\u27s cartilage are derived from larval chondrocytes. Our data also suggest that most adult cartilages form de novo, though we cannot rule out the potential for extreme larval chondrocyte proliferation or de- and re-differentiation, which could dilute our fluorescent protein signal. The transgenic lineage tracing strategies developed here are the first examples of inducible, skeleton-specific, lineage tracing in Xenopus
Coherent states on spheres
We describe a family of coherent states and an associated resolution of the
identity for a quantum particle whose classical configuration space is the
d-dimensional sphere S^d. The coherent states are labeled by points in the
associated phase space T*(S^d). These coherent states are NOT of Perelomov type
but rather are constructed as the eigenvectors of suitably defined annihilation
operators. We describe as well the Segal-Bargmann representation for the
system, the associated unitary Segal-Bargmann transform, and a natural
inversion formula. Although many of these results are in principle special
cases of the results of B. Hall and M. Stenzel, we give here a substantially
different description based on ideas of T. Thiemann and of K. Kowalski and J.
Rembielinski. All of these results can be generalized to a system whose
configuration space is an arbitrary compact symmetric space. We focus on the
sphere case in order to be able to carry out the calculations in a
self-contained and explicit way.Comment: Revised version. Submitted to J. Mathematical Physic
Performance evaluation of the Boron Coated Straws detector with Geant4
The last decade has witnessed the development of several alternative neutron
detector technologies, as a consequence of upcoming neutron sources and
upgrades, as well the world-wide shortage of He. One branch of development
is the family of B-based gaseous detectors. This work focuses on the
boron coated straws (BCS) by Proportional Technologies Inc., a commercial
solution designed for use in homeland security and neutron science. A detailed
Geant4 simulation study of the BCS is presented, which investigates various
aspects of the detector performance, e.g. efficiency, activation, absorption
and the impact of scattering on the measured signal. The suitability of the BCS
detector for Small Angle Neutron Scattering (SANS), direct chopper spectrometry
and imaging is discussed.Comment: 50 pages, 37 figures, minor changes after review, results unchange
Semiclassical energy formulas for power-law and log potentials in quantum mechanics
We study a single particle which obeys non-relativistic quantum mechanics in
R^N and has Hamiltonian H = -Delta + V(r), where V(r) = sgn(q)r^q. If N \geq 2,
then q > -2, and if N = 1, then q > -1. The discrete eigenvalues E_{n\ell} may
be represented exactly by the semiclassical expression E_{n\ell}(q) =
min_{r>0}\{P_{n\ell}(q)^2/r^2+ V(r)}. The case q = 0 corresponds to V(r) =
ln(r). By writing one power as a smooth transformation of another, and using
envelope theory, it has earlier been proved that the P_{n\ell}(q) functions are
monotone increasing. Recent refinements to the comparison theorem of QM in
which comparison potentials can cross over, allow us to prove for n = 1 that
Q(q)=Z(q)P(q) is monotone increasing, even though the factor Z(q)=(1+q/N)^{1/q}
is monotone decreasing. Thus P(q) cannot increase too slowly. This result
yields some sharper estimates for power-potential eigenvlaues at the bottom of
each angular-momentum subspace.Comment: 20 pages, 5 figure
2009 Precision Planted Corn Performance Trials
This publication reports the results of the 2009 South Dakota corn hybrid performance trials for glyphosate-resistant hybrids. Information includes both the most recent 2-year and 1-year grain yields in bushels per acre and 1-year bushel weight, grain moisture at harvest, lodging percentage, and final stand percentages. These performance trials are conducted by the South Dakota Crop Performance Testing program at South Dakota State University. Corn performance trial tables are listed on the inside front cover. Environmental data is listed in tables A and B, indices of brand/hybrid entries to performance table number are listed in table C, table D has the footnote legend, and mailing addresses for seed companies are listed in table E
2008 Precision Planted Performance Trials: Corn
This publication reports the results of the 2008 South Dakota corn hybrid performance trials for both glyphosate-resistant hybrids and non-glyphosate-resistant hybrids. Information includes both the most recent two-year and one-year grain yields in bushels per acre; and one-year bushel weight, grain moisture at harvest, lodging percentage, and final stand percentages. These performance trials are conducted by the South Dakota Crop Performance Testing program at South Dakota State University. Corn performance trial tables are listed on the inside front cover. Environmental data is listed in tables A and B, indices of brand/ hybrid entries to performance table number are listed in table C, table D has the footnote legend, and mailing addresses for seed companies are listed in table E
2007 Precision Planted Performance Trials: Corn
This publication reports the performance of entries in the 2007 South Dakota corn hybrid performance trials for both non-Roundup-Ready™ and Roundup-ReadyTM hybrids. Information includes the most recent two-year and one-year grain yield averages, in bushels per acre, and one-year averages for bushel weight, grain moisture at harvest, percent stand at harvest, and stalk lodging percentages. These performance trials are conducted by the South Dakota Crop Performance Testing program at South Dakota State University. Corn performance trial tables are listed on the inside front cover. Environmental data is listed in tables A and B, indices of brand/hybrid entries to performance table number are listed in tables C and D, and mailing addresses for seed companies are listed in table E
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