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12C +12 C is the main reaction during core and shell carbon burning in massive stars, however, at temperatures higher than 109K when most of the carbon is depleted and its abundance is lower than 16O, the 12C +16 O fusion can also become relevant. Moreover, 12C +16 O reaction can ignite also in the scenario of explosive carbon burning. The astrophysical energy region of interest thus ranges from 3 to 7.2 MeV in the center-of-mass frame. There are various measurements of the cross-section available in the literature, however, they all stop around 4 MeV, making extrapolation necessary at lower energies. To try to solve this uncertainty and corroborate direct measurement the Trojan Horse Method was applied to three-body processes 16O(14N, α24Mg)2H and 16O(14N, p27Al)2H to study the 16O(12C, α)24Mg and 16O(12C, p)27Al reactions.

The carbon-burning process in massive stars mainly occurs via the 12C +12 C. However, at temperatures higher than 109K and considering the increased abundance of 16O produced during the later stages of the heliumburning,the 12C+16O fusion can also become relevant. Moreover, 12C+16O also plays a role in the scenario of explosive carbon burning. Thus, the astrophysical energy region of interest ranges from 3 to 7.2 MeV in the center-of-mass frame. However, the various measurements of the cross-section available in the literature stop around 4 MeV, making extrapolation necessary. To solve this uncertainty and corroborate direct measurement we applied the Trojan Horse Method to three-body processes 16O(14N, α24Mg)2H and 16O(14N, p27Al)2H to study the 12C(16O, α)24Mg and 12C(16O, p)27Al reactions in their entire energy region of astrophysical interest. In this contribution, after briefly describing the method used, the experiment and the preliminary phases of the data analysis will be presented and discussed.

A large uncertainty for the slow neutron capture nucleosynthesis (s-process) models is caused by the amount of neutrons available to the process itself. This quantity is strongly affected by the 13C(α,n)16O, and 22Ne(α,n)25Mg reaction cross sections, whose measurements at energies corresponding to the s-process thermal conditions (∼102 keV) are mainly hampered by the Coulomb barrier. For this reason, indirect approaches could offer a complementary way of investigation and, among these, the Trojan Horse Method (THM) has been applied to determine these cross sections overcoming the Coulomb barrier. With this approach, a low-energy binary reaction cross section can be obtained selecting the quasi-free contribution from a suitable three-body reaction cross section, taking advantage of the cluster structure of proper nuclei.

The Asymptotic Normalization Coefficient (ANC) method, has proven to be useful in retrieving the direct part of the radiative capture cross section for a number of reactions of astrophysical interest. In this work, some of the latest results obtained by the AsFin2 group of the LSN-INFN (Catania) and the OJR of the NPI (Řež) will be briefly discussed.

The $$^{27}\hbox {Al}(\hbox {p},\alpha )^{24}\hbox {Mg}$$ 27 Al ( p , α ) 24 Mg reaction, which drives the destruction of $$^{27}$$ 27 Al and the production of $$^{24}\hbox {Mg}$$ 24 Mg in stellar hydrogen burning, has been investigated via the Trojan Horse Method (THM), by measuring the $$^2\hbox {H}(^{27}\hbox {Al},\alpha ^{24}\hbox {Mg})\hbox {n}$$ 2 H ( 27 Al , α 24 Mg ) n three-body reaction. The experiment covered a broad energy range ($$E_\mathrm{c.m.}\le \,1.5\,\hbox {MeV}$$ E c . m . ≤ 1.5 MeV ), aiming to investigate those of interest for astrophysics. The results confirm the THM as a valuable technique for the experimental study of fusion reactions at very low energies and suggest the presence of a rich pattern of resonances in the energy region close to the Gamow window of stellar hydrogen burning (70–120 keV), with potential impact on astrophysics. To estimate such an impact a second run of the experiment is needed, since the background due the three-body reaction hampered to collect enough data to resolve the resonant structures and extract the reaction rate.

The $^{26}\mathrm{Si}(p,\ensuremath{\gamma})^{27}\mathrm{P}$ reaction might be relevant in understanding the $^{26}\mathrm{Si}$ depletion and $^{26}\mathrm{Al}$ production in stars. The asymptotic normalization coefficients (ANC) for the $^{26}\mathrm{Si}(p,\ensuremath{\gamma})^{27}\mathrm{P}$ reaction were extracted earlier from the reanalysis of $^{26}\mathrm{Mg}(d,p)^{27}\mathrm{Mg}$ and $^{26}\mathrm{Mg}(t,d)^{27}\mathrm{Mg}$ reactions, in which the deduced ANC's show significant discrepancies. In this work, a dedicated ($d,p$) measurement is presented: the ANC for the $^{27}\mathrm{Mg}\ensuremath{\rightarrow}\phantom{\rule{0.16em}{0ex}}^{26}\mathrm{Mg}+n$ virtual decay is deduced from the $^{26}\mathrm{Mg}(d,p)^{27}\mathrm{Mg}$ reaction populating the ground and the first excited state of $^{27}\mathrm{Mg}$ using the distorted wave Born approximation (DWBA). The charge symmetry properties for mirror nuclei have been used to calculate the ANC for the direct capture $^{26}\mathrm{Si}+p\ensuremath{\rightarrow}\phantom{\rule{0.16em}{0ex}}^{27}\mathrm{P}$ populating the ground state of $^{27}\mathrm{P}$. By means of the same formalism, the ${\mathrm{\ensuremath{\Gamma}}}_{p}$ width for the first excited state has also been deduced. The reaction rate is also updated using recent values for the ${\mathrm{\ensuremath{\Gamma}}}_{\ensuremath{\gamma}}/{\mathrm{\ensuremath{\Gamma}}}_{p}$ ratio measured by [Sun et al., Phys. Rev. C 99, 064312 (2019); Sun et al., Phys. Lett. B 802, 135213 (2020)].

The unbound proton-rich nuclei $$^{16}$$ F and $$^{15}$$ F are investigated experimentally and theoretically. Several experiments using the resonant elastic scattering method were performed at GANIL with radioactive beams to determine the properties of the low lying states of these nuclei. Strong asymmetry between $$^{16}$$ F– $$^{16}$$ N and $$^{15}$$ F– $$^{15}$$ C mirror nuclei is observed. The strength of the $$nucleon-nucleon$$ effective interaction involving the loosely bound proton in the $$s_{1/2}$$ orbit is significantly modified with respect to their mirror nuclei $$^{16}$$ N and $$^{15}$$ C. The reduction of the effective interaction is estimated by calculating the interaction energies with a schematic zero-range force. It is found that, after correcting for the effects due to changes in the radial distribution of the single-particle wave functions, the mirror symmetry of the $$n-p$$ interaction is preserved between $$^{16}$$ F and $$^{16}$$ N, while a difference of 63% is measured between the $$p-p$$ versus $$n-n$$ interactions in the second excited state of $$^{15}$$ F and $$^{15}$$ C nuclei. Several explanations are proposed.

Nuclear reactions play a key role in the framework of the Big Bang Nucleosynthesis. A network of 12 principal reactions has been identified as the main path that drove the elemental nucleosynthesis in the first 20 min of the history of the Universe. Among them an important role is played by neutron-induced reactions, which, from an experimental point of view, are usually a difficult task to be measured directly. Nevertheless big efforts in the last decades have led to a better understanding of their role in the primordial nucleosynthesis network. In this work we apply the Trojan Horse Method to extract the cross section at astrophysical energies for the $$^3\text {He}$$ (n,p) $$^3\text {H}$$ reaction after a detailed study of the $$^2\hbox {H}$$ ( $$^3\text {He}$$ ,pt)H three-body process. Data extracted from the present measurement are compared with other published sets.

Among the indirect methods to determine nuclear cross-section present in literature, the so-called Asymptotic Normalization Coefficient (ANC) has proven to be useful in retrieving the direct part of a radiative capture cross-section in reactions of interest for astrophysics. In this work, the method will be presented, and some results obtained in collaboration between NPI CAS and INFN-LNS will be presented.

A new study of the quasi-free contribution to the $$^3\hbox {He}+\,^9\hbox {Be}\rightarrow 3\alpha $$ reaction (Q value = 19.004 MeV) at low $${E}_{^3{{\mathrm{He}}}}$$ energy is presented. The reaction was studied in a kinematically complete experiment at beam energy of 4 MeV. To clarify the presence of the quasi-free mechanism, the $$^4{\hbox {He}}$$–$$^5\hbox {He}$$ momentum distribution of the $$^9\hbox {Be}$$ ground state was extracted. Standard tests were also carried out to confirm the presence of the quasi-free contribution and are reported in this work. The full width at half maximum of the $$^4\hbox {He}$$–$$^5\hbox {He}$$ inter-cluster momentum distribution inside $$^9\hbox {Be}$$ was measured with improved accuracy, by adopting several different approaches that all led to consistent results. These preliminary investigations on the reaction mechanism are fundamental for future studies employing the Trojan Horse Method, with the $$^5\hbox {He}$$ unbound nucleus as a virtual projectile.

Neutron induced reactions are fundamental for the nucleosynthesis of elements in the universe. Indeed, to correctly study the reactions involved in the well-known s-process in stars, which produce about half of the elements beyond the iron peak, it is mandatory to know the neutron abundance available in those stars. The 17O(n, a)14C reaction is one of the so-called “neutron poisons” for the pro- cess and it could play an important role in the balance of the neutron abundance. The reaction is therefore investigated in the energy range of astrophysical inter- est between 0 and 350 keV in the center of mass by applying the Trojan Horse Method to the three body reaction 2H(17O, a14C)H.

In the network of reactions present in the Big Bang nucleosynthesis, the 3He(n, p)3H has an important role which impacts the final 7Li abundance. The Trojan Horse Method (THM) has been applied to the 3He(d, pt)H reaction in order to extract the astrophysical S(E)-factor of the 3He(n, p)3H in the Gamow energy range. The experiment will be described in the present work together with the first preliminary results.

In the network of reactions present in the Big Bang nucleosynthesis, the 3He(n, p)3H reaction has an important role which impacts the final 7Li abundance. The Trojan Horse Method (THM) has been applied to the 3He(d, pt)H reaction in order to extract the astrophysical S(E)-factor of the 3He(n, p)3H reaction in the Gamow energy range. The experiment will be described in the present work together with the first preliminary results.

The observational 19F abundance in stellar environments systematically exceeds the predicted one, thus representing one of the unsolved challenges for stellar modeling. It is therefore clear that further investigation is needed in this field. In this work, we focus our attention on the measurement of the 19F(α, p) 22Ne reaction in the astrophysical energy range, between 0.2 and 0.8 MeV (far below the Coulomb barrier, 3.8 MeV), as it represents the main destruction channel in He-rich environments. The lowest energy at which this reaction has been studied with direct measurements is ∼0.66 MeV, covering only the upper tail of the Gamow window, causing the reaction-rate evaluation to be based on extrapolation. To investigate lower energies, the 19F(α, p) 22Ne reaction has been studied by means of the Trojan horse method, applied to the quasi-free 6Li (19F, p22Ne)2H reaction at Ebeam = 6 MeV. The indirect cross section of the 19F(α, p) 22Ne reaction at energies ≲1 MeV was extracted, fully covering the astrophysical region of interest and overlapping existing direct data for normalization. Several resonances have been detected for the first time inside the Gamow window. The reaction rate has been calculated, showing an increase up to a factor of 4 with respect to the literature at astrophysical temperatures. This might lead to potential major astrophysical implications.

In the last years the [Formula: see text]O and the [Formula: see text]F([Formula: see text],p)[Formula: see text]Ne reactions have been studied via the Trojan Horse Method in the energy range of interest for astrophysics. These are the first experimental data available for the main channels of [Formula: see text]F destruction that entirely cover the energy regions typical of the stellar H- and He- burning. In both cases the reaction rates are significantly larger than the previous estimations available in the literature. We present here a re-analysis of the fluorine nucleosynthesis in Asymptotic Giant Branch stars by employing in state-of-the-art models of stellar nucleosynthesis the THM reaction rates for [Formula: see text]F destruction.

Many r.c. structures have to be strengthened or retrofitted to resist higher design loads. This happens when there is a change of the use destination or when the structures are damaged because of an aggressive environment. Besides, nowadays, attention has moved to restoring, recovering and seismically retrofitting the r.c. structures The knowledge that r.c. is alone, not always, capable of reaching the structural seismic requirements has given the drive to combine it together with an innovative material such as CFRP. That is, the strengthening of the r.c. structural elements by using externally bonded CFRP, which seems to be an effective solution and also the most economical one, over a long period of time. But sometimes, the compressed zone of concrete fails because it is not capable of sustaining the new stress state produced by the increase of resistance of the structural element. In this paper we discuss an innovative technology, consisting of gluing a joist of polyurethane, at the internal face of the frame mesh and wrapped by CFRP layers. So an increasing of its flexural capacity and stiffness, while maintaining a manageable member weight, can be reached. Once strengthened, this will show a ductility capable of resisting the horizontal action by avoiding the introduction, either of the very heavy r.c. layers or the steel plates. We report the results of an experimental test compared with non-strengthened-frame ones. The hysteretical loops of the reinforced frame, derived from the tests, are sensibly wider, so this retrofitting technology seems to be very similar to the technology consisting of applying, in frame mesh, some hysteretical devices which permit an unloading of the seismic energy from the main structure. For this reason the same original frame was tested coupled with a particular device designed tested and patented by the same author. In this

Two nuclear reactions of astrophysical interest, 26Mg(3He,d)27Al and 26Mg(d,p)27Mg, were measured for extraction of the Asymptotic Normalization Coefficients. Investigation of the target composition is presented, as well as the effects that showed up during analysis of the in-beam data obtained on CANAM accelerators in the Nuclear Physics Institute of the Czech Academy of Sciences (NPI CAS).

Balloon atrial septostomy (BAS) is of established value in the management of several congenital heart diseases in the neonatal period. This procedure, which leads to creation of a tear in the membrane of the Foramen Ovalis using a balloon catheter, may be undertaken under fluoroscopic monitoring in catheter laboratory as well as under echographic control, even bedside. In this study we present our experience and discuss the indications to these two techniques. 91 neonates underwent to BAS; in 14 of them this was carried out under two-dimensional echocardiographic control in the intensive care unit. In all the patients BAS had good result, with clinical improvement in the majority of cases (97%) and a low rate (6%) of minor complications (such as transient supraventricular arrhythmias), without differences between fluoroscopic and ultrasound monitoring. The higher rate of mortality in the fluoroscopic monitoring group (2/91 = 2.2%) was thought to depend on an extremely critical presentation of the neonates. The echographic monitoring does not seem to offer any real advantage from the technical point of view, but the necessity of a prompt treatment of very ill patients emphasizes the advantages of a quickly and easily feasible procedure. Thus, we recommend the use two-dimensional echocardiographic imaging only in the very ill neonates in whom the septostomy can be more safely performed in intensive care unit bedside.

In order to assess the relative incidence of varicocele (V) alone and V+ coincidental didymo-epididymal morphological abnormalities (DEMA) and the role of these pathologies on the pre- and post-surgical sperm outcome, 151 selected (previous exclusion of cases with bilateral V, seminal infections, antisperm autoAb) patients (aged 20-41 yrs) affected by left V at Doppler ultrasonography, underwent both ultrasound scrotal content examinations and semen analyses (sperm density, total sperm count, forward motility and normal morphology employing as frequency distribution) before and after varicocelectomy (on months 4-8-12, taking for statistical comparison the maximal post-surgical sperm value registered vs. mean correspective pre-treatment value). One-hundred two (67.5%) patients exhibited V alone (group A), whilst 49 (32.5%) patients showed V+DEMA (group B). As regards V, DEMA lesions (testis size12 ml; epididymides abnormalities: increased head (11 mm) and/or tail (6 mm) diameter, multiple microcysts; large idrocele) were omolaterally in 21/49 (42.8%) eterolaterally in 11/49 (22.5%) or bilaterally in 17/49 (34.7%). An additional group of 25 patients, exhibiting the above ultrasonic DEMA lesions alone without V, served as controls (group C) for semen statistical analysis in the pre-surgical period only. In this phase among groups A vs B, A vs C, B vs C, frequency distributions of all sperm parameters studied (excepted for density not significative only between B and C group patients) were significantly different. The following data were registered from A, B and C patient groups respectively: a) azoospermia was present in 12.7%, 34.8% and 24%; b) oligozoospermia (20 mil/ml) in 39.2%, 49% and 48%; c) normozoospermia in 48.1%, 16.3% and 8%; d) total sperm count was40 millions/ejaculate in 44.1%, 91.9% and 76%; e) asthenozoospermia (forward motility25%) was present in 32.3%, 71.4% e 72%; f) teratozoospermia (oval form30%) was present in 34.3%, 62.3% and 48%. In the post-surgical follow-up examinations, significative changes with ameliorated frequency distributions of all semen parameters were observed within group A only, while these same parameters remained unmodified within group B patients, thus being together a significative difference between groups A vs B higher than that observed in the pretreatment. The coexistence of DEMA+V seems to determine two important effects on sperm output: a) in the pre-treatment, this selection judgement allowed to distinguish a different frequency distribution of semen parameters between patients affected by V alone and V+DEMA; b) since patients with V alone in comparison with V+DEMA patients groups had a favourable sperm outcome, the assessment of DEMA in patients with V seems to be mandatory for a better sperm prognostic judice.

A 33-year-old man was hospitalized for hyperpyrexia and pain in the left upper quadrant of his abdomen. Abdominal ultrasound showed a mass in the inferior pole of the spleen. A computed axial tomography of the abdomen and a liver and spleen scintigraphy confirmed a space-occupying lesion in the spleen but were not able to define its nature. A FNAB performed during abdominal ultrasound showed cells with elliptic nuclei and elongated pale blue cytoplasm, separated from each other by empty spaces of varying width. The presence of a hemangioma or lymphangioma of the spleen was suspected. A splenectomy was performed. The histologic findings were compatible with a cavernous hemangioma. After a review of the literature, the role of FNAB of the spleen is discussed as a reasonable diagnostic approach that assists the clinician in making therapeutic decisions in the management of the space-occupying lesions in the spleen. The possibility of differentiating benign from malignant lesions is pointed out, particularly those of endothelial nature. Finally, the differential diagnosis between hamartoma and hemangioma of the spleen is discussed. The two words, in times past, were often used for the same lesion, producing a confusion of names in literature.

Personal experience with 100 cases of jejunostomy for feeding purposes is reported. Stress is laid on the advantages of this feeding technique which include simple, surgical technique, easy administration of diet, speedy metabolic response and the moderate nature of the complications.

We report the first case, in our knowledge, of dietary intolerance only to the rice in childhood. Gastrointestinal symptoms and shock-like state in relation to the ingestion of ground rice were observed in a 5-month-old girl. At 34 months she was still clinically intolerant to this food.

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