1,470 research outputs found
Drug delivery systems - Winter school on recent advances in diagnosis and management of diseases in mariculture, 7th to 27th November 2002, Course Manual
Drug delivery systems are designed based on the action of the drug in the body,
reaction of the body to these drugs and the active drug available in the body for
therapeutic action. The way a drug is made to reach the destination and act at the
appropriate site is the drug delivery systems
From Matrices to Strings and Back
We discuss an explicit construction of a string dual for the Gaussian matrix
model. Starting from the matrix model and employing Strebel differential
techniques we deduce hints about the structure of the dual string. Next,
following these hints a worldheet theory is constructed. The correlators in
this string theory are assumed to localize on a finite set of points in the
moduli space of Riemann surfaces. To each such point one associates a Feynman
diagram contributing to the correlator in the dual matrix model, and thus
recasts the worldsheet expression as a sum over Feynman diagrams.Comment: 27 pages, 3 figure
D-branes as a Bubbling Calabi-Yau
We prove that the open topological string partition function on a D-brane
configuration in a Calabi-Yau manifold X takes the form of a closed topological
string partition function on a different Calabi-Yau manifold X_b. This
identification shows that the physics of D-branes in an arbitrary background X
of topological string theory can be described either by open+closed string
theory in X or by closed string theory in X_b. The physical interpretation of
the ''bubbling'' Calabi-Yau X_b is as the space obtained by letting the
D-branes in X undergo a geometric transition. This implies, in particular, that
the partition function of closed topological string theory on certain bubbling
Calabi-Yau manifolds are invariants of knots in the three-sphere.Comment: 32 pages; v.2 reference adde
(De)Constructing Dimensions
We construct renormalizable, asymptotically free, four dimensional gauge
theories that dynamically generate a fifth dimension.Comment: 10 pages, late
Refined Topological Vertex and Instanton Counting
It has been proposed recently that topological A-model string amplitudes for
toric Calabi-Yau 3-folds in non self-dual graviphoton background can be
caluculated by a diagrammatic method that is called the ``refined topological
vertex''. We compute the extended A-model amplitudes for SU(N)-geometries using
the proposed vertex. If the refined topological vertex is valid, these
computations should give rise to the Nekrasov's partition functions of N=2
SU(N) gauge theories via the geometric engineering. In this article, we verify
the proposal by confirming the equivalence between the refined A-model
amplitude and the K-theoretic version of the Nekrasov's partition function by
explicit computation.Comment: 22 pages, 6 figures, minor correction
Perturbative Chern-Simons Theory From The Penner Model
We show explicitly that the perturbative SU(N) Chern-Simons theory arises
naturally from two Penner models, with opposite coupling constants. As a result
computations in the perturbative Chern-Simons theory are carried out using the
Penner model, and it turns out to be simpler and transparent. It is also shown
that the connected correlators of the puncture operator in the Penner model,
are related to the connected correlators of the operator that gives the Wilson
loop operator in the conjugacy class.Comment: 7 Pages, Published Versio
Reduction of open membrane moduli
We perform a general reduction of the open membrane metric in a worldvolume
direction of the M5-brane. Using reduction rules analogous to the bulk, we show
that the open membrane metric leads to the standard open string metric and open
string coupling constant on the D4-brane only for an ``electric'' reduction in
which case the open membrane metric has no off-diagonal components and the
Born-Infeld curvature tensor is a matrix of rank 2. Instead, if we perform a
general reduction, with nonzero off-diagonal components of the open membrane
metric, we obtain a rank 4 Born-Infeld tensor corresponding to a bound state of
an open string with an open D2--brane. Next, we identify and reduce a 3-form
open membrane ``noncommutativity'' tensor on the M5-brane. This open membrane
parameter only reduces to the open string noncommutativity tensor on the
D4-brane provided we constrain ourselves to an ``electric'' or a ``magnetic''
reduction.Comment: 15 pages, LaTeX, uses JHEP.cls and JHEP.bst style file
Simplifying and Extending the AdS_5xS^5 Pure Spinor Formalism
Although the AdS_5xS^5 worldsheet action is not quadratic, some features of
the pure spinor formalism are simpler in an AdS_5xS^5 background than in a flat
background. The BRST operator acts geometrically, the left and right-moving
pure spinor ghosts can be treated as complex conjugates, the zero mode measure
factor is trivial, and the b ghost does not require non-minimal fields.
Furthermore, a topological version of the AdS_5xS^5 action with the same
worldsheet variables and BRST operator can be constructed by gauge-fixing a G/G
principal chiral model where G=PSU(2,2|4). This topological model is argued to
describe the zero radius limit that is dual to free N=4 super-Yang-Mills and
can also be interpreted as an "unbroken phase" of superstring theory.Comment: 39 pages harvma
't Hooft Expansion of 1/2 BPS Wilson Loop
We revisit the 't Hooft expansion of 1/2 BPS circular Wilson loop in N=4 SYM
studied by Drukker and Gross in hep-th/0010274. We find an interesting
recursion relation which relates different number of holes on the worldsheet.
We also argue that we can turn on the string coupling by applying a certain
integral transformation to the planar result.Comment: 21 pages; v2: minor correction
Whitebaits
The present status of exploitation of whitebaits and
information on their biology and stock position are reviewed.
Encrasicholina devisi and Stolephorus waitei together account for
major share of the whitebait catch. Aspects of fishery, size
distribution in the fishery, size at first maturity, spawning season
and seasons of young fish abundance for both the species at
different observation centres are presented. Food of these species
comprised chiefly of copepods and other zooplankters. The exploitation
rate for S. waitei were 0.48 and 0.38 and for E. devisi 0.29
and 0.15 respectively along the east and west coasts. E. devisi is
poorly exploited along both the coasts. E. devisi and E. punctifer
are hardy, and can survive in captivity for one to three months and
could therefore be utilised as live baits in the tuna pole and line
fishery
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