9,540 research outputs found
Summer air temperature anomalies in Europe during the century 1811-1910
Solar cycle, volcanic eruptions, sea surface temperature anomalies (ENSO) and increase of the concentration of the greenhouse gases are the main forcing factors in the evolution of the Earth climate. Therefore, a sizeable amount of research is devoted to assess the impact of these factors on the climate parameters, as the mean air temperature. In the present work a study concerning the behaviour of the summer temperatures over Europe during the century 1811-1910 is carried out. The possible influence of the volcanic eruptions and ENSO has been also analysed. The results show the presence of a volcanic signal in the summer
temperature during the year following an eruption, even if the anomalous coldest summers do not seem to be driven by the volcanic activity. The connection between thermal anomalies and ENSO events is more uncertain because of the paucity of data. Finally, the anomalous summers—both very cold and very warm—can be explained in terms of the atmospheric circulation, since cold events seem to be
associated to persistent blocking systems and warm events are associated to persistent high-pressure patterns
Rainfall over the Central-Western Mediterranean basin in the period 1951-1995. Part I: precipitation trends
Climatic changes due to the anthropic enhancement of the greenhouse effect could modify the hydrological cycle, resulting in a reduction of the precipitation over the Mediterranean basin. In particular, a negative trend over the Italian peninsula could occur with prolonged periods of dryness as that recorded in the biennium 1988-1990. In order to verify if a climatic variability is already
detectable, the pluviometric regime over the Central-Western Mediterranean is here analysed for the period 1951-1995. The analysis indicates that a reduction of about
20% in the total precipitation has occurred, which is statistically significant and can have serious impact on the availability of the water supplies
A reduction of the resonant three-wave interaction to the generic sixth Painleve' equation
Among the reductions of the resonant three-wave interaction system to
six-dimensional differential systems, one of them has been specifically
mentioned as being linked to the generic sixth Painleve' equation P6. We derive
this link explicitly, and we establish the connection to a three-degree of
freedom Hamiltonian previously considered for P6.Comment: 13 pages, 0 figure, J. Phys. A Special issue "One hundred years of
Painleve' VI
On elliptic solutions of the cubic complex one-dimensional Ginzburg-Landau equation
The cubic complex one-dimensional Ginzburg-Landau equation is considered.
Using the Hone's method, based on the use of the Laurent-series solutions and
the residue theorem, we have proved that this equation has neither elliptic
standing wave nor elliptic travelling wave solutions. This result amplifies the
Hone's result, that this equation has no elliptic travelling wave solutions.Comment: LaTeX, 12 page
Barium alginate capsules for 3D immobilisation of living cells: morphology, membrane properties and permeability
Encapsulation in a barium alginate membrane is a promising strategy to obtain a three dimensional culture of living cells: membrane properties are crucial for a realistic clinical application. A one-step encapsulation technique, recently developed for controlled release of boar semen, was employed to prepare barium alginate and protamine-alginate membranes: permeability to two model molecules (haemoglobin and glucose) was evaluated. Capsules were evaluated for technological properties and scanning electron microscopy was used to examine the external morphology of the capsules and the 3D distribution of the cells within the core. The results indicate that 3D arrangement and cell shape are maintained, capsule dimensions and mechanical properties can be modulated, as well as their permeability to model molecules such as haemoglobin and glucose
Control of mucocutaneous leishmaniasis, a neglected disease: results of a control programme in Satipo Province, Peru.
Mucocutaneous leishmaniasis (MCL) is an important health problem in many rural areas of Latin America, but there are few data on the results of programmatic approaches to control the disease. We report the results of a control programme in San Martin de Pangoa District, which reports one of the highest prevalences of MCL in Peru. For 2 years (2001--2002), the technicians at the health post were trained in patient case management, received medical support and were supplied with antimonials. An evaluation after 2 years showed the following main achievements: better diagnosis of patients, who were confirmed by microscopy in 34% (82/240) of the cases in 2001 and 60% of the cases (153/254) in 2002; improved follow-up during treatment: 237 of 263 (90%) patients who initiated an antimonial therapy ended the full treatment course; improved follow-up after treatment: 143 of 237 (60%) patients who ended their full treatment were correctly monitored during the required period of 6 (cutaneous cases) or 12 (mucosal cases) months after the end of treatment. These achievements were largely due to the human and logistical resources made available, the constant availability of medications and the close collaboration between the Ministry of Health, a national research institute and an international non-governmental organization. At the end of this period, the health authorities decided to register a generic brand of sodium stibogluconate, which is now in use. This should allow the treatment of a significant number of additional patients, while saving money to invest in other facets of the case management
Cyclic Mobility Effects on Soil-Pile Interaction in Dense Sand
A methodology to evaluate the effects of earthquake-induced cyclic mobility in dense sand on the soil-pile interaction parameters is presented. The soil behavior under cyclic loading is defined based on the interpretation of consolidated-undrained cyclic triaxial tests on samples reconstituted to the in situ relative density and shear wave velocity. The stress distribution around the pile is determined analytically, and the softened zone is modelled by an annulus of softer soil. The application of this methodology for the design of three submerged-floating tunnels in the Messina straits, Italy, indicated that even in dense sand the foundation stiffness reduction can be considerable during an earthquake. Comparisons with different approaches available from the literature are discussed
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