5,560 research outputs found
What if quality of damage data is poor: an exposure-vulnerability approach for flood vulnerability assessment
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A novel approach to flood risk assessment: the Exposure-Vulnerability matrices
The classical approach to flood defence, focused on reducing the probability of flooding through hard defences, has been gradually substituted by flood risk management approach, which accepts the idea of coping with floods, and aims at reducing both probability and the consequences of flooding. In this view, the concept of vulnerability becomes central, such as the (non-structural) measures for its increment. However, the evaluations for the effectiveness and methods of non-structural measure and the vulnerability are less studied, compared to the structural solutions. In this paper, we adopted the Longano catchment in Sicily, Italy, as the case study. The methodology developed in the work enabled a qualitative evaluation of the consequences of floods, based on a crisscross analysis of vulnerability curves and classes of exposure for assets at risk. A GIS-based tool was used to evaluate each element at risk inside an Exposure-Vulnerability matrix. The construction of an E-V matrix allowed a better understanding of the actual situation within a catchment and the effectiveness of non-structural measures for a site. Referring directly to vulnerability can also estimate the possible consequences of an event even in those catchments where the damage data are absent. The instrument proposed can be useful for authorities responsible for development and periodical review of adaptive flood risk management plans
Strings from geometric tachyon in Rindler space and black hole thermodynamics
The dynamics of a probe particle or wrapped brane moving in the
two-dimensional Rindler space can be described by a time-dependent tachyon
field theory. Using knowledge of tachyon condensation, we learn that the
infalling brane gets thermalised and produces open string pairs at the Hagedorn
temperature when entering into the near-horizon Rindler wedge. It is shown that
the Hagedorn temperature of the infalling brane is equal to the Hawking
temperature of the host black hole detected in the same time coordinate. The
infalling brane will decay completely into closed strings, mainly massive
modes, when it reaches the horizon in infinitely long time as observed by
observers at spatial infinity. Preliminary estimates indicate that the
degeneracy of states of the closed strings emitted from the infalling brane
should be responsible for the increased entropy in the host black hole due to
absorption of the brane.Comment: 12 page
symmetry and quasi-normal modes in the BTZ black hole
With the help of two new intrinsic tensor fields associated with the
quadratic Casimir of Killing fields, we uncover the
symmetry satisfied by the solutions to the equations of motion for various
fields in the BTZ black hole in a uniform way by performing tensor and spinor
analysis without resorting to any specific coordinate system. Then with the
standard algebraic method developed recently, we determine the quasi-normal
modes for various fields in the BTZ black hole. As a result, the quasi-normal
modes are given by the infinite tower of descendants of the chiral highest
weight mode, which is in good agreement with the previous analytic result
obtained by exactly solving equations of motion instead.Comment: JHEP style, 1+13 pages, version to appear in JHE
P-wave Quarkonium Decays to Meson Pairs
The processes of P-wave Quarkonium exclusive decays to two mesons are
investigated, in which the final state vector mesons with various polarizations
are considered separately. In the calculation, the initial heavy quarkonia are
treated in the framework of non-relativistic quantum chromodynamics, whereas
for light mesons, the light cone distribution amplitudes up to twist-3 are
employed. It turns out that the higher twist contribution is significant and
provides a possible explanation for the observation of the hadron helicity
selection rule violated processes
by the BESIII collaboration in recently. We also evaluate the process and find that its branching ratio is big enough to be
measured at the B-factories.Comment: more results and discussions adde
Stem cell differentiation increases membrane-actin adhesion regulating cell blebability, migration and mechanics
This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder in order to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/K. S. is funded by an EPSRC PhD studentship. S.T. is funded by an EU Marie Curie Intra European Fellowship (GENOMICDIFF)
Holographic Superconductors from Einstein-Maxwell-Dilaton Gravity
We construct holographic superconductors from Einstein-Maxwell-dilaton
gravity in 3+1 dimensions with two adjustable couplings and the charge
carried by the scalar field. For the values of and we
consider, there is always a critical temperature at which a second order phase
transition occurs between a hairy black hole and the AdS RN black hole in the
canonical ensemble, which can be identified with the superconducting phase
transition of the dual field theory. We calculate the electric conductivity of
the dual superconductor and find that for the values of and where
is small the dual superconductor has similar properties to the
minimal model, while for the values of and where is
large enough, the electric conductivity of the dual superconductor exhibits
novel properties at low frequencies where it shows a "Drude Peak" in the real
part of the conductivity.Comment: 25 pages, 13 figures; v2, typos corrected; v3, refs added, to appear
in JHE
Biomineralization mediated by anaerobic methane-consuming cell consortia
published_or_final_versio
Charged Dilatonic AdS Black Branes in Arbitrary Dimensions
We study electromagnetically charged dilatonic black brane solutions in
arbitrary dimensions with flat transverse spaces, that are asymptotically AdS.
This class of solutions includes spacetimes which possess a bulk region where
the metric is approximately invariant under Lifshitz scalings. Given fixed
asymptotic boundary conditions, we analyze how the behavior of the bulk up to
the horizon varies with the charges and derive the extremality conditions for
these spacetimes.Comment: References update
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