10,622 research outputs found
Regulating Sperm Donation: Why Requiring Exposed Donation Is Not the Answer
[...] the risk of incest and consanguinity11 are prevalent with anonymous donation12 since there is no monitoring of the number of live births per donor. [...] the number of children born from sperm donation has doubled in recent years.30 Although sperm may be donated by a relative or close friend of the couple or individual, often the sperm is donated anonymously through a sperm bank or clinic
Power loss and electromagnetic energy density in a dispersive metamaterial medium
The power loss and electromagnetic energy density of a metamaterial
consisting of arrays of wires and split-ring resonators (SRRs) are
investigated. We show that a field energy density formula can be derived
consistently from both the electrodynamic (ED) approach and the equivalent
circuit (EC) approach. The derivations are based on the knowledge of the
dynamical equations of the electric and magnetic dipoles in the medium and the
correct form of the power loss. We discuss the role of power loss in
determining the form of energy density and explain why the power loss should be
identified first in the ED derivation. When the power loss is negligible and
the field is harmonic, our energy density formula reduces to the result of
Landau's classical formula. For the general case with finite power loss, our
investigation resolves the apparent contradiction between the previous results
derived by the EC and ED approaches.Comment: 10 pages, 1 figure, Submitted to Phys. Rev.
Conformal quantum mechanics as the CFT dual to AdS
A 0+1-dimensional candidate theory for the CFT dual to AdS is
discussed. The quantum mechanical system does not have a ground state that is
invariant under the three generators of the conformal group. Nevertheless, we
show that there are operators in the theory that are not primary, but whose
"non-primary character" conspires with the "non-invariance of the vacuum" to
give precisely the correlation functions in a conformally invariant theory.Comment: 6 page
Novel software techniques for automatic microwave measurements
Although many microwave measurement techniques are heavily based on special purpose software, the application of modern software techniques like object oriented programming and new programming language like C++ is seldom used. The impact of such new software solutions can drastically improve the overall design of a microwave test set. The paper presents the design and implementation of a new multiport network analyzer with particular attention to the control program architecture. The use of Object Oriented Programming techniques results in a clear and easy to maintain solution which boosts both the user interface and the overall test set organizatio
Jets and Jet Multiplicities in High Energy Photon-Nucleon Inetraction:
We discuss the theory of jet events in high-energy photon-proton interactions
using a model which gives a good description of the data available on total
inelastic cross sections up to =210 GeV. We show how to
calculate the jet cross sections and jet multiplicities and give predictions
for these quantities for energies appropriate for experiments at the HERA
collider and for very high energy cosmic ray observations.Comment: 12 pages + 4 figs, MAD/TH/92-8, submitted to Phys. Rev. D(Rapid
Communications), figs. available on request from [email protected]
Finite size effects in adsorption of helium mixtures by alkali substrates
We investigate the behavior of mixed 3He-4He droplets on alkali surfaces at
zero temperature, within the frame of Finite Range Density Functional theory.
The properties of one single 3He atom on 4He_N4 droplets on different alkali
surfaces are addressed, and the energetics and structure of 4He_N4+3He_N3
systems on Cs surfaces, for nanoscopic 4He drops, are analyzed through the
solutions of the mean field equations for varying number N3 of 3He atoms. We
discuss the size effects on the single particle spectrum of 3He atoms and on
the shapes of both helium distributions.Comment: 12 pages, and 12 figures (PNG format
Renal transplantation at the university of Colorado
From March 1962 to April 1963, 118 patients were treated with renal transplantation, 3 with kidneys from identical twins, 9 with cadaveric homografts, and 106 with homografts from volunteer donors. Sixty-two of the patients are still alive after nine months to almost five years. The only completely satisfactory group was that of the identical twin recipients. The results after homotransplantation have not materially improved during this time despite the acquisition of increased experience, adjustments of timing and dosage of azathioprine and prednisone, and attempts to identify biologically suitable donors in advance of operation by tissue typing. It is suggested that an impasse has been reached, beyond which further reduction in mortality and morbidity will depend primarily upon the effective application of new immunosuppressive techniques. © 1967 by The Williams and Wilkins Co
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