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Radiative Heating of an Ice-Free Arctic Ocean
During recent decades, there has been dramatic Arctic sea ice retreat. This has reduced the top-of-atmosphere albedo, adding more solar energy to the climate system. There is substantial uncertainty regarding how much ice retreat and associated solar heating will occur in the future. This is relevant to future climate projections, including the timescale for reaching global warming stabilization targets. Here we use satellite observations to estimate the amount of solar energy that would be added in the worst-case scenario of a complete disappearance of Arctic sea ice throughout the sunlit part of the year. Assuming constant cloudiness, we calculate a global radiative heating of 0.71 W/m2 relative to the 1979 baseline state. This is equivalent to the effect of one trillion tons of CO2 emissions. These results suggest that the additional heating due to complete Arctic sea ice loss would hasten global warming by an estimated 25 years
Exploring the Potential of Urban Coastal Interfaces for Socio-Environmental Connections: The Cases of Marseille and Naples
Contemporary coastal cities intertwine variegated stakes, linked to the economic, productive and social functions of the seashore, and need a correct management aimed at balancing the different needs and at maintaining a high ecological status of the coasts themselves. A fracture emerges between the urban development of coastal areas and the social desire and expectations of the 'urban coastal society', a community intimately connected to the coast and sea elements. Port and productive evolution has often neglected the socio-recreational component inherent in coastal areas, related to its attractiveness for citizens, the presence of natural qualities and an undeniable visual and perceptual value that influence the use of these places, influencing the conformation of coastal public spaces.
The integrity of the urban coasts appears fragmented by the juxtaposition of variegated elements which can however be considered as pieces of a potential green-blue infrastructure, with a view to recomposing the city-sea interface. The contribution aims to investigate the management and design criticalities that affect urban blue spaces, mainly in relation to the implications related to leisure and sociality, proposing a historical, spatial and socio-perceptive comparison between Naples and Marseille
Nonparametric Information Geometry
The differential-geometric structure of the set of positive densities on a
given measure space has raised the interest of many mathematicians after the
discovery by C.R. Rao of the geometric meaning of the Fisher information. Most
of the research is focused on parametric statistical models. In series of
papers by author and coworkers a particular version of the nonparametric case
has been discussed. It consists of a minimalistic structure modeled according
the theory of exponential families: given a reference density other densities
are represented by the centered log likelihood which is an element of an Orlicz
space. This mappings give a system of charts of a Banach manifold. It has been
observed that, while the construction is natural, the practical applicability
is limited by the technical difficulty to deal with such a class of Banach
spaces. It has been suggested recently to replace the exponential function with
other functions with similar behavior but polynomial growth at infinity in
order to obtain more tractable Banach spaces, e.g. Hilbert spaces. We give
first a review of our theory with special emphasis on the specific issues of
the infinite dimensional setting. In a second part we discuss two specific
topics, differential equations and the metric connection. The position of this
line of research with respect to other approaches is briefly discussed.Comment: Submitted for publication in the Proceedings od GSI2013 Aug 28-30
2013 Pari
Coarse-grained entanglement classification through orthogonal arrays
Classification of entanglement in multipartite quantum systems is an open
problem solved so far only for bipartite systems and for systems composed of
three and four qubits. We propose here a coarse-grained classification of
entanglement in systems consisting of subsystems with an arbitrary number
of internal levels each, based on properties of orthogonal arrays with
columns. In particular, we investigate in detail a subset of highly entangled
pure states which contains all states defining maximum distance separable
codes. To illustrate the methods presented, we analyze systems of four and five
qubits, as well as heterogeneous tripartite systems consisting of two qubits
and one qutrit or one qubit and two qutrits.Comment: 38 pages, 1 figur
ANATOMICAL DISSECTION AND ANALYSIS OF THE STRUCTURES OF THE UPPER LIMB
In 2015, a whole body dissection course was proposed by the University of Palermo, Palermo, Italy, thanks to the cooperation with the University of Malta, Msida, Malta. The purpose of this study was to show the the difference between the studyof anatomy on books and on corpses. The article focuses its attention on the dissection method of the upper limb. The astudy was performed on two corpses, a male and a female, by using a basic surgeon kit. Blunt dissection method was used for fasciae, innards and to isolate vascular-nervous structures from the fat; we used scalped for cutis, sub cutis, muscles, fasciae, veins, arteries and nerves of the upper limb from the shoulder to the hand. The upper limb dissection shows the difference between how a real body appears and shows the difference between how a real body appears and how books represent it
A Class of Non-Parametric Statistical Manifolds modelled on Sobolev Space
We construct a family of non-parametric (infinite-dimensional) manifolds of finite measures on Rd. The manifolds are modelled on a variety of weighted Sobolev spaces, including Hilbert-Sobolev spaces and mixed-norm spaces. Each supports the Fisher-Rao metric as a weak Riemannian metric. Densities are expressed in terms of a deformed exponential function having linear growth. Unusually for the Sobolev context, and as a consequence of its linear growth, this "lifts" to a nonlinear superposition (Nemytskii) operator that acts continuously on a particular class of mixed-norm model spaces, and on the fixed norm space W²'š i.e. it maps each of these spaces continuously into itself. It also maps continuously between other fixed-norm spaces with a loss of Lebesgue exponent that increases with the number of derivatives. Some of the results make essential use of a log-Sobolev embedding theorem. Each manifold contains a smoothly embedded submanifold of probability measures. Applications to the stochastic partial differential equations of nonlinear filtering (and hence to the Fokker-Planck equation) are outlined
Molecular screening for bacterial pathogens in ticks (Ixodes ricinus) collected on migratory birds captured in northern Italy
Migratory birds have an important role in transporting ticks and associated tick-borne pathogens over long distances. In this study, 2,793 migratory birds were captured by nets in a ringing station, located in northern Italy, and checked for the presence of ticks. Two-hundred and fifty-one ticks were identified as nymphs and larvae of Ixodes ricinus (Linnaeus, 1758) and they were PCR-screened for the presence of bacteria belonging to Borrelia burgdorferi sensu lato, Rickettsia spp., Francisella tularensis and Coxiella burnetii. Four species of Borrelia (B. garinii, B. afzelii, B. valaisiana and B. lusitaniae) and three species of Rickettsia (R. monacensis, R. helvetica and Candidatus Rickettsia mendelii) were detected in 74 (30%) and 25 (10%) respectively out of 251 ticks examined. Co-infection with Borrelia spp. and Rickettsia spp. in the same tick sample was encountered in 7 (7%) out of the 99 infected ticks. We report for the first time the presence of Candidatus Rickettsia mendelii in I. ricinus collected on birds in Italy. This study, besides confirming the role of birds in dispersal of I. ricinus, highlights an important route by which tick-borne pathogens might spread across different countries and from natural environments towards urbanised areas
Optimal measures and Markov transition kernels
We study optimal solutions to an abstract optimization problem for measures,
which is a generalization of classical variational problems in information
theory and statistical physics. In the classical problems, information and
relative entropy are defined using the Kullback-Leibler divergence, and for
this reason optimal measures belong to a one-parameter exponential family.
Measures within such a family have the property of mutual absolute continuity.
Here we show that this property characterizes other families of optimal
positive measures if a functional representing information has a strictly
convex dual. Mutual absolute continuity of optimal probability measures allows
us to strictly separate deterministic and non-deterministic Markov transition
kernels, which play an important role in theories of decisions, estimation,
control, communication and computation. We show that deterministic transitions
are strictly sub-optimal, unless information resource with a strictly convex
dual is unconstrained. For illustration, we construct an example where, unlike
non-deterministic, any deterministic kernel either has negatively infinite
expected utility (unbounded expected error) or communicates infinite
information.Comment: Replaced with a final and accepted draft; Journal of Global
Optimization, Springer, Jan 1, 201
Observation of two new baryon resonances
Two structures are observed close to the kinematic threshold in the mass spectrum in a sample of proton-proton collision data, corresponding
to an integrated luminosity of 3.0 fb recorded by the LHCb experiment.
In the quark model, two baryonic resonances with quark content are
expected in this mass region: the spin-parity and
states, denoted and .
Interpreting the structures as these resonances, we measure the mass
differences and the width of the heavier state to be
MeV,
MeV,
MeV, where the first and second
uncertainties are statistical and systematic, respectively. The width of the
lighter state is consistent with zero, and we place an upper limit of
MeV at 95% confidence level. Relative
production rates of these states are also reported.Comment: 17 pages, 2 figure
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