63,860 research outputs found
Anti-D-brane as Dark Matter in Warped String Compactification
It is pointed out that in the warped string compactification, motion of
anti-D-branes near the bottom of a throat behaves like dark matter. Several
scenarios for production of the dark matter are suggested, including one based
on the D/anti-D interaction at the late stage of D/anti-D inflation.Comment: 8 pages, version accepted for publication as a Rapid Communication in
PRD, discussion about mass and production of dark matte
The control of Corynebacterium pseudotuberculosis infection in sheep flocks : a mathematical model of the impact of vaccination, serological testing, clinical examination and lancing of abscesses
A mathematical model of Corynebacterium pseudotuberculosis infection in sheep flocks was used to evaluate strategies for control and elimination of caseous lymphadenitis (CIA). Control strategies tested were vaccination, serological testing and removal of seropositives, clinical examination and removal of sheep with abscesses, lancing abscesses, and appropriate combinations. Three different infection rates with and without replacement of culled ewes were used to evaluate the control options. Controls were either implemented immediately after infection was detected in a flock or once CIA was at endemic equilibrium, and with different frequencies of examination or testing. Elimination of infection was defined as 99% confidence that no sheep were infected with C. pseudo tuberculosis. The control strategies were evaluated by estimating the reduction in infection or probability of elimination and the number of ewes culled from the flock.
Lancing abscesses reduced the prevalence of infection when the initial prevalence was 0.90, but vaccination combined with clinical examination reduced infection rapidly with little impact on lamb productivity. Further research is required to develop a diagnostic test with at least 0.90 specificity and sensitivity under field conditions before any methods of control can be recommended with confidence
The Formation of Thin Continuous Films from Isolated Nuclei
Formation of thin continuous films from isolated nuclei and effect of electron beam, residual gases, and surface conditions on film growt
Connection between the Loop Variable Formalism and the Old Covariant Formalsm for the Open Bosonic String
The gauge invariant loop variable formalism and old covariant formalism for
bosonic open string theory are compared in this paper. It is expected that for
the free theory, after gauge fixing, the loop variable fields can be mapped to
those of the old covariant formalism in bosonic string theory, level by level.
This is verified explicitly for the first two massive levels. It is shown that
(in the critical dimension) the fields, constraints and gauge transformations
can all be mapped from one to the other. Assuming this continues at all levels
one can give general arguments that the tree S-matrix (integrated correlation
functions for on-shell physical fields) is the same in both formalisms and
therefore they describe the same physical theory (at tree level).Comment: Latex file, 24 page
Momentum Analyticity and Finiteness of the 1-Loop Superstring Amplitude
The Type II Superstring amplitude to 1-loop order is given by an integral of
-functions over the moduli space of tori, which diverges for real
momenta. We construct the analytic continuation which renders this amplitude
well defined and finite, and we find the expected poles and cuts in the complex
momentum plane.Comment: 10pp, /UCLA/93/TEP/
Frequency-dependent electrical characteristics of DNA using molecular dynamics simulation
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