The Dynamical Dipole Mode in Dissipative Heavy Ion Collisions

We study the effect of a direct Giant Dipole Resonance ($GDR$) excitation in intermediate dinuclear systems with exotic shape and charge distributions formed in charge asymmetric fusion entrance channels. A related enhancement of the $GDR$ gamma yield in the evaporation cascade of the fused nucleus is expected. The dynamical origin of such $GDR$ extra strength will show up in a characteristic anisotropy of the dipole gamma-emission. A fully microscopic analysis of the fusion dynamics is performed with quantitative predictions of the $GDR$ photon yield based on a dynamics- statistics coupling model. In particular we focus our attention on the energy and mass dependence of the effect. We suggest a series of new experiments, in particular some optimal entrance channel conditions. We stress the importance of using the new available radioactive beams.Comment: 20 pages (Latex), 14 Postscript figure

Potassium channels and bioelectrical cellular properties during interactions with conductive polymers, electrotaxis and accelerated aging

Bioelectrical properties of the plasma membrane heavily characterize a living cell, they govern manifold functions of the cellular machinery and their alteration may lead to breakdown in its metabolism, loss of homeostasis, and finally death. By monitoring the potassium voltage-gated ion channels activity it was possible to study different topics. First, the interaction between cells and redox forms of organic films made by poly(3,4-ethylenedioxythiophene):poly(styre-nesulfonate) (PEDOT:PSS) was investigated, finding that the redox processes confer to PEDOT:PSS substrates the property to modify the ionic environment at the film-liquid interface through a “sponge-like” effect on ions, affecting cellular electrophysiology and functionality. Subsequently cell migration was studied under the action of external electric fields through the use of a programmable electronic board; preliminary results verified the success of this device in creating and controlling galvanotactic events. Finally, the premature aging process in cells carrying a G608G LMNA mutation, known as Hutchinson-Gilford Progeria Syndrome (HGPS) was assessed; highlighting that cells affected by HGPS overexpress BKCa channels on plasma membrane, and this seems to be correlated with an impaired replicative potential if compared to healthy cells

Reactions induced by 11Be beam at Rex-Isolde

The collision induced by the three Beryllium isotopes, 9,10,11Be, on a 64Zn target were investigated at Ec.m. ≈ 1.4 the Coulomb barrier. The experiments with the radioactive 10,11Be beams were performed at the Rex-Isolde facility at CERN. In the case of 9,10Be, elastic scattering angular distributions were measured whereas, in the 11Be case, the quasielastic scattering angular distribution was obtained. A strong damping of the quasielastic cross-section was observed in the 11Be case, in the angular range around the Coulomb-nuclear interference peak. In this latter case a large total-reaction cross-section is found. Such a cross-section is more than a factor of two larger than the ones extracted in the reactions induced by the non-halo Beryllium isotopes. A large contribution to the total-reaction cross-section in the 11Be case could be attributed to transfer and/or break-up event

First experimental evidence of 2He decay from 18Ne excited states

Two-proton decay from 18Ne excited states has been studied by complete kinematical detection of the decay products. The 18Ne nucleus has been produced as a radioactive beam by 20Ne projectile fragmentation at 45 AMeV on a 9Be target, using the FRIBs in-flight facility of the LNS. The 18Ne at 33 AMeV incident energy has been excited via Coulomb excitation on a natPb target. The correlated 2p emission has been disentangled from the uncorrelated 2p emission using a high granularity particle detector setup allowing the reconstruction of momentum and angle correlations of the two emitted protons. The obtained results unambiguously show that the 6.15 MeV 18Ne state two-proton decay proceeds through 2He emission (31%) and democratic or virtual sequential decay (69%)

Implementing the European Space Agency’s SentiNel application platform’s open-source Python module for differential synthetic aperture radar interferometry coseismic ground deformation from Sentinel-1 data

Differential SAR Interferometry is a largely exploited technique to study ground deformations. A key application is the detection of the effects promoted by earthquakes, including detailed variations in ground deformations at different scales. In this work, an implemented Python script (Snap2DQuake) based on the “snappy” module by SNAP software 9.0.8 (ESA) for the processing of satellite imagery is proposed. Snap2DQuake is aimed at producing detailed coseismic deformation maps using Sentinel-1 C-band data by the DInSAR technique. With this alternative approach, the processing is simplified, and several issues that may occur using the software are solved. The proposed tool has been tested on two case studies: the Mw 6.4 Petrinja earthquake (Croatia, December 2020) and the Mw 5.7 to Mw 6.3 earthquakes, which occurred near Tyrnavós (Greece, March 2021). The earthquakes, which occurred in two different tectonic contexts, are used to test and verify the validity of Snap2DQuake. Snap2DQuake allows us to provide detailed deformation maps along the vertical and E-W directions in perfect agreement with observations reported in previous works. These maps offer new insights into the deformation pattern linked to earthquakes, demonstrating the reliability of Snap2DQuake as an alternative tool for users working on different applications, even with basic coding skills.Peer ReviewedPostprint (published version

Effects of silvicultural treatment on the stability of black pine plantations.

Black pine plantations have been established at the purpose of recovering a forest cover to marginal soils, mostly throughout the Apennines range in Italy, since the end of the eighteenth century and up to the mid 1900. Both the decay of forest cover and soil erosion were the outcome of the long-lasting overuse through the intensive forest exploitation practices, grazing of the forest floor and wildfires, occurring since many centuries ago. The primary function of pine reafforestation was therefore to re-establish a first cover with a pioneer species, preparatory to future mixed forest types based on the natural reintroduction of broadleaves originally living in the same areas, mainly deciduous oaks and beech in the upper part. These goals have been partly met over the wide reafforestation area; the key functions of pine stands are today the protection against soil erosion and the hydrological regulation of catchments. The pine stands have been assuming today also a scenic role because they have been incorporated in the landscape physiognomy. A series of thinning up to the regeneration phase had been planned by foresters since the design of these plantations, but many stands have grown unthinned and fully stocked for a long time, this condition contributing a less mechanical stability of trees. Alternative forms of regeneration in grown-up stands have been and are being tested to improve both the natural and artificial establishment of indigenous species, but thinnings remain, even if a tardy measure, the main practice enforceable to these pine forests. The results of experimental trials undertaken in the black pine forest stand located in Pratomagno casentinese (Arezzo) are being reported in the paper. The study started in 1978 and the following theses were tested (A) heavy thinning from below; (B) moderate thinning from below; (C) control. Three thinnings were carried out in 1978, 1999 and 2009 at the ages of 24, 45 and 55. The action over time of each intervention on the mensurational and mechanical stability parameters (H/D ratio H/Ddom ratio), are being analyzed. The stability parameters of the pine forest after three interventions (H/D ratio, crown ratio, horizontal crown projection and eccentricity of the crown) have been also analyzed on a sample of trees per thesis and compared with those of trees grown in absence of competition. Sampled trees were sorted per social class. Results proved that type, interval and intensity of thinning related to the age of intervention are the main determinants of a successful treatment. Thinnings from below increase individual stability over time only when also trees living in the main crop layer are being removed. The trials showed the improvement of stability parameters following the intermediate thinning applied at the age of 45. The thesis of heavy thinning had the best performance as for the awaited purpose

Elastic scattering of Beryllium isotopes near the Coulomb barrier

In this contribution, results of experiments performed with the three Beryllium isotopes 9,10,11Be on a medium mass 64Zn target, at a center of mass energy of≈1.4 the Coulomb barrier, will be discussed. Elastic scattering angular distributions have been measured for the 9,10Be reactions. In the 11Be case the quasielastic scattering angular distribution was obtained. In the halo nucleus case, the angular distribution exhibit a non-Fresnel-type pattern with a strong damping of the Coulombnuclear interference peak. Moreover, it is found that the total reaction cross-section for the halo nucleus induced collision is more than double the ones extracted in the collisions induced by the non-halo Beryllium isotopes. A large contribution to the total-reaction cross-section in the 11Be case could be attributed to transfer and/or break-up events

Stand dynamics of a beech coppice beyond the rotation age and under conversion into high forest.

 One of major issues dealing with forest management in Italy is the lack or the suspension of silvicultural practices over an increased share of the forest area, in progress since a few decades ago. The abandonment of rural areas, the emerging environmental functions being nowadays addressed to natural resources, include also many forests and management systems formerly devoted mainly to wood production. This occurrence has its major evidence on coppice forests, i.e. about a half of the country forest area and the forest type historically submitted to the more intensive management practices. The results of an experimental trial started in 1972 in a beech coppice aged 27, i.e. a few years after the age of traditional rotation, comparing the natural evolutive pattern as well as the silvicultural practices aimed at its conversion into high forest, are here reported. The trial included the control thesis and three different thinning intensities. Each thesis was arranged within the same thinning type, taking into account the volume of former standing crop in each plot. The analysis includes the growth pattern and the dynamics of stand structure in the populations under natural evolution and under conversion into high forest. Four inventories were carried out since 1972 at each decade up to 2002. Three thinnings were undertaken within the same time. Results show that both the tested management options, alternative and/or complementary to the traditional coppice system, are based on reliable biological assumptions. The natural evolutive pattern highlights the growth trend at ages older than those monitored under the coppice system. Beech shows a peculiar behaviour in the range observed due to its specific shade-tolerance. The shoot population reveals a sustained growth between the ages of 30 to 40; then, the occurrence of a heavy, regular mortality up to 50; finally, the recovery of a high growth rate up to the age of 60 (ending of the monitored period at now). Such growth pattern moves up the current volume increment, delays its intersection to mean increment and postpones substantially the age of growth rates culmination. The observed trend deviates from the canonical stand growth pattern and seems to be grounded on beech auto-ecology. This extends the time of reaction between the opposite feedbacks of mortality and growth and allows monitoring a likely different behaviour ruling ageing coppice growth. The same occurrence had not been highlighted before studying light-demanding species (deciduous oaks in the case) under the same stand types, these species being able to settle much more rapidly the cycle mortality-growth recovery-incremental culmination. The thesis of conversion into high forest provides the technical cultivation rules (type, intensity and interval of thinning repetition) and suggests it as enforceable also in the private domain due to the shortly-repeated harvestings and intermediate volumes that make each intervention profitable. The basic outcomes of the applied silvicultural practices are (i) the early crown shaping of shoot dendrotypes; (ii) the modeling of clustered stand structure; (iii) the individual development of well-balanced trees, more suited to tackle the grown-up and mature stages till the time of regeneration from seed, ending of the transitory cycle