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Evaluation of an urban NMHC emission inventory by measurements and impact on CTM results
This paper presents an evaluation of the consistency of an urban state-of-the-art hydrocarbon (HC) emission inventory. The evaluation was conducted through the comparison of this inventory with hourly HC measurements during two summer months in the centre of Marseille, on the Mediterranean French coast. Factors of under or overestimation could be calculated for each compound on the basis of a systematic HC to HC ratio analysis. These results, associated with a deep analysis of the speciation profiles, show that most of the common and highly concentrated hydrocarbons (such as butanes) are too much predominant in the emission speciation, while the heavy and less common species (branched alkanes, substituted aromatics) are under-represented in the inventory. The urban diffuse sources appear here as one critical point of the inventories. The disagreements were shown to have a strong incidence on the representation of the air mass reactivity. In a last step, the identified uncertainties in emissions were implemented in an air-quality model for sensitivity studies. It was shown that the observed biases in the inventory could affect the regional ozone production, with a probable impact on ozone peaks of 2-10 ppbv over the area. © 2010 Elsevier Ltd
General integral relations for the description of scattering states using the hyperspherical adiabatic basis
In this work we investigate 1+2 reactions within the framework of the
hyperspherical adiabatic expansion method. To this aim two integral relations,
derived from the Kohn variational principle, are used. A detailed derivation of
these relations is shown. The expressions derived are general, not restricted
to relative partial waves, and with applicability in multichannel
reactions. The convergence of the -matrix in terms of the adiabatic
potentials is investigated. Together with a simple model case used as a test
for the method, we show results for the collision of a He atom on a \dimer
dimer (only the elastic channel open), and for collisions involving a Li
and two He atoms (two channels open).Comment: Accepted for publication in Physical Review
Variational description of continuum states in terms of integral relations
Two integral relations derived from the Kohn Variational Principle (KVP) are
used for describing scattering states. In usual applications the KVP requires
the explicit form of the asymptotic behavior of the scattering wave function.
This is not the case when the integral relations are applied since, due to
their short range nature, the only condition for the scattering wave function
is that it be the solution of in the internal region.
Several examples are analyzed for the computation of phase-shifts from bound
state type wave functions or, in the case of the scattering of charged
particles, it is possible to obtain phase-shifts using free asymptotic
conditions. As a final example we discuss the use of the integral relations in
the case of the Hyperspherical Adiabatic method.Comment: 34 pages, 7 figures, accepted in Phys. Rev.
The helium trimer with soft-core potentials
The helium trimer is studied using two- and three-body soft-core potentials.
Realistic helium-helium potentials present an extremely strong short-range
repulsion and support a single, very shallow, bound state. The description of
systems with more than two helium atoms is difficult due to the very large
cancellation between kinetic and potential energy. We analyze the possibility
of describing the three helium system in the ultracold regime using a gaussian
representation of a widely used realistic potential, the LM2M2 interaction.
However, in order to describe correctly the trimer ground state a three-body
force has to be added to the gaussian interaction. With this potential model
the two bound states of the trimer and the low energy scattering helium-dimer
phase shifts obtained with the LM2M2 potential are well reproduced.Comment: 15 pages, 3 figures, submitted to Few-Body System
Stato dell’arte dei Piani di Emergenza per il Massiccio Afflusso di Feriti (PEMAF) negli ospedali italiani. Studio pilota
Aim of this study is to assess the level of implementation of plans for the massive influx of injured (PEMAF) in Italian hospitals.
An anonymous questionnaire was administered to a sample of 100 hospitals selected through the network of the Italian Society of Emergency Medicine (SIMEU). Each answer of the questionnaire was assigned a score, then reported on a scale of compliance (maximum 65 points, threshold 35 points). The average scores
were analyzed by hospital’s venue, level of activity and previous experience of managing a real emergency. Student’s t-test was used to compare means.
Thirty-two hospitals sent the questionnaire, representing 33% of those selected. Five were excluded for incomplete data. The data analyzed refers to 27 hospitals of various levels of complexity, from all around the country: 55.6% from the Northern Section, 22.2% from the Centre and 22.2% from the Southern section and
the Islands; and only 55.6% are above the minimum threshold of compliance. The weakest PEMAF’s area is the one related to the specific training of health workers, therefore the percentage of hospitals complying the requirements in this field is down to 37%. Ten hospitals (37%) had managed a real maxi-emergence in the past: belonging to such group of hospitals is associated with an average level of compliance significantly higher than the others (p<0,005).
Due to a limited percentage of responders, the study involved so far a too small amount of hospitals; happily, they were evenly distributed in the different sections of the Country; therefore it will be appropriate to obtain a larger compliance before reaching clear-cut conclusions, but it already appears that the most critical point is the lack of specific education to maxi-emergencies in the hospital personnel
Seasonal variations in eelgrass (Zostera marina l.) responses to nutrients availability.
Relationship between water column and pore water nutrient concentrations on the growth of the Zostera marina L. in the Numana harbour (Adriatic Sea) was investigated. High concentrations of dissolved inorganic nitrogen in the water column and in the pore water were not related with plant growth. In contrast phosphate concentrations in the water column appeared a limiting factor
Posidonia oceanica (L.) delile dampens cell migration of human neuroblastoma cells
Neuroblastoma (NB) is a common cancer in childhood, and lethal in its high-risk form, primarily because of its high metastatic potential. Targeting cancer cell migration, and thus preventing metastasis formation, is the rationale for more effective cancer therapy against NB. Previous studies have described the leaf extract from Posidonia oceanica marine plant (POE) as an antioxidant, anti-inflammatory agent and inhibitor of cancer cell migration. This study aims to examine the POE anti-migratory role in human SH-SY5Y neuroblastoma cells and the underlying mechanisms of action. Wound healing and gelatin zymography assays showed that POE at early times inhibits cell migration and reduces pro-MMP-2 release into culture medium. By monitoring expression level of key autophagy markers by Western blot assay, a correlation between POE-induced cell migration inhibition and autophagy activation was demonstrated. Cell morphology and immunofluorescence analyses showed that POE induces neurite formation and neuronal differentiation at later times. These results suggest POE might act against cell migration by triggering early nontoxic autophagy. The POE-induced cellular morphological change toward cell differentiation might contribute to prolonging the phytocomplex anti-migratory effect to later times. Overall, these results encourage future in vivo studies to test POE applicability in neuroblastoma treatment
Integral relations for three-body continuum states with the adiabatic expansion
Application of the Hyperspherical Adiabatic expansion to describe three-body
scattering states suffers the problem of a very slow convergence. Contrary to
what happens for bound states, a huge number of hyperradial equations has to be
solved, and even if done, the extraction of the scattering amplitude is
problematic. In this paper we show how to obtain accurate scattering phase
shifts using the Hyperspherical Adiabatic expansion. To this aim two integral
relations, derived from the Kohn Variational Principle, are used. The
convergence of this procedure is as fast as for bound states.Comment: 4 pages, 1 figur
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