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Different excited states of 13 C populated in the 10 B + 10 B reactions at a beam energy of 72.2 MeV were investigated. The study revealed both well-known and new, or infrequently populated states. In particular, the inclusive excitation energy spectra showed the presence of most of the states belonging to the K = 3/2 - rotational band that was proposed by several authors. Furthermore, a possibly new state at E x = 19.0 MeV was strongly populated in the α + 9 Be coincidences. The measured state was found to have a well defined cluster structure. Additionally, so far unobserved α -decay of the two rarely seen high-energy 13 C states at 21.9 and 23.6 MeV is discussed. [ABSTRACT FROM AUTHOR]

The presence of crystallographic defects can induce notable effects on the mechanisms ruling the current transport in metal/semiconductor contacts. In this context, in this Letter, the impact of stacking faults (SFs) on the characteristics of 4H-SiC Schottky diodes was investigated under both forward and reverse bias. In particular, in the presence of SFs under the contact, while no significant effect on the ideality factor and barrier height was observed under forward bias, an anomalous increase in the leakage current occurred under reverse bias. The observed behavior of the leakage current could be explained by a space-charge limited current model, consistent with the presence of a distribution of trapping states in the gap of 4H-SiC. An increase in the reverse bias above 30 V leads to a complete trap filling. The weak temperature-dependence of the leakage current observed in this regime suggests the coexistence with a tunneling of the carriers through the barrier. The results can be useful to understand unexpected failures in 4H-SiC Schottky diodes. [ABSTRACT FROM AUTHOR]

Third-generation TiO2 photocatalysts were prepared by implantation of C+ ions into 110 nm thick TiO2 films. An accurate structural investigation was performed by Rutherford backscattering spectrometry, secondary ion mass spectrometry, X-ray diffraction, Raman-luminescence spectroscopy, and UV/VIS optical characterization. The C doping locally modified the TiO2 pure films, lowering the band-gap energy from 3.3 eV to a value of 1.8 eV, making the material sensitive to visible light. The synthesized materials are photocatalytically active in the degradation of organic compounds in water under both UV and visible light irradiation, without the help of any additional thermal treatment. These results increase the understanding of the C-doped titanium dioxide, helpful for future environmental applications. [ABSTRACT FROM AUTHOR]

Summary: To assess the impact of socioeconomic status (SES) on the occurrence of skin cancer in the population living in the province of Ferrara, Italy, a retrospective cohort of patients with squamous cell carcinoma (SCC), basal cell carcinoma (BCC) or malignant melanoma (MM), provided by the local cancer registry, was investigated. The SES was expressed through an ecological‐based deprivation index. During the 8‐year study period (2006–2013, total person‐years 2 859 137), 6051 carcinomas (1535 SCCs, 4365 BCCs) and 459 MMs were diagnosed. Both crude and standardized (on the European population) rates and the standardized incidence ratio showed a direct correlation between BCC and SES. Multivariate analysis confirmed these results for BCC and also for MM, while it showed an excess of SCC incidence in the lowest SES subgroup. This study shows, for the first time, to our knowledge, opposite effects of SES on SCC and BCC occurrence. A role of environmental factors conditioned by SES may be hypothesized. [ABSTRACT FROM AUTHOR]

This work shows the application of metal ion-implantation to realize an efficient second-generation TiO2 photocatalyst. High fluence Fe+ ions were implanted into thin TiO2 films and subsequently annealed up to 550 °C. The ion-implantation process modified the TiO2 pure film, locally lowering its band-gap energy from 3.2 eV to 1.6-1.9 eV, making the material sensitive to visible light. The measured optical band-gap of 1.6-1.9 eV was associated with the presence of effective energy levels in the energy band structure of the titanium dioxide, due to implantation-induced defects. An accurate structural characterization was performed by Rutherford backscattering spectrometry, transmission electron microscopy, Raman spectroscopy, X-ray diffraction, and UV/VIS spectroscopy. The synthesized materials revealed a remarkable photocatalytic efficiency in the degradation of organic compounds in water under visible light irradiation, without the help of any thermal treatments. The photocatalytic activity has been correlated with the amount of defects induced by the ion-implantation process, clarifying the operative physical mechanism. These results can be fruitfully applied for environmental applications of TiO2. [ABSTRACT FROM AUTHOR]

We have investigated the formation and the morphology of carbon deposit on the cathode, after arc discharge between two graphite electrodes immersed in liquid nitrogen. We show that the deposit is mainly composed of disordered carbon structures at the bottom and at the external part of the deposit, forming like a bowl, whereas randomly oriented carbon nanotubes (CNTs) aggregated as pillars are found at the center of the deposit. The spatial distribution of the two kinds of structures in the deposit, the size and the sharpness of the CNT pillars are found to depend both on the applied voltage and the current values used for the arc discharge. A correlation between the plasma temperature field and the morphology of the deposit is reported. [ABSTRACT FROM AUTHOR]

Arc discharge between two graphite rods in liquid nitrogen has been investigated in order to identify the main factors ruling the formation of carbon nanotubes (CNTs) and linear C chains. The influence of the experimental parameters on the structural properties of the produced materials was evaluated and interpreted, taking into account the existing models. We found that the electrode size and discharge current values greatly influence the structural quality of the nanotubes (e.g., presence of carbonaceous impurities, innermost tube diameter) and a proper combination of these parameters allows one to control the synthesis of CNTs and/or CNT-linear C chain hybrid systems. [ABSTRACT FROM AUTHOR]

Radio frequency magnetron sputtering has been used for the synthesis of aligned carbon nanotubes (CNTs) on a SiO2/Si substrate, with simultaneous in situ catalyst deposition. This method allows the use of substrates without the need of a surface predeposition of catalytic particles. In particular, among the metals considered, we observed the formation of CNTs using W or Ni as catalysts. Only in the case of Ni did we find that the CNTs are aligned along the target-substrate direction, unlike the randomly oriented CNTs observed when W was used as catalyst. Scanning and transmission electron microscopies show that the catalytic Ni nanoparticle is found mostly on the tip of the obtained bamboolike CNTs, while W nanoparticles are encapsulated inside hollow nanotubes, at different points along their length. We ascribe not only the observed structural differences to the size of the W and Ni particles but also to a different diffusion behavior of C in the two kinds of metallic clusters. [ABSTRACT FROM AUTHOR]

The Time-of-Flight (TOF) technique coupled with semiconductorlike detectors, as silicon carbide and diamond, is one of the most promising diagnostic methods for high-energy, high repetition rate, laser-accelerated ions allowing a full on-line beam spectral characterization. A new analysis method for reconstructing the energy spectrum of high-energy laser-driven ion beams from TOF signals is hereby presented and discussed. The proposed method takes into account the detector's working principle, through the accurate calculation of the energy loss in the detector active layer, using Monte Carlo simulations. The analysis method was validated against well-established diagnostics, such as the Thomson parabola spectrometer, during an experimental campaign carried out at the Rutherford Appleton Laboratory (UK) with the high-energy laser-driven protons accelerated by the VULCAN Petawatt laser. [ABSTRACT FROM AUTHOR]

Background Laparoscopic resection of posterosuperior ( PS) segments of the liver is hindered by limited visualization and curvilinear resection planes. The aim of this study was to compare outcomes after open and laparoscopic liver resections of PS segments. Methods Patients who underwent minor open liver resection ( OLR) and laparoscopic liver resection ( LLR) between 2006 and 2014 were identified from the institutional databases of seven tertiary referral European hepatobiliary surgical units. Propensity score-matched analysis was used to match groups for known confounders. Perioperative outcomes including complications were assessed using the Dindo-Clavien classification, and the comprehensive complication index was calculated. Survival was analysed with the Kaplan-Meier method. Results Some 170 patients underwent OLR and 148 had LLR. After propensity score-matched analysis, 86 patients remained in both groups. Overall postoperative complication rates were significantly higher after OLR compared with LLR: 28 versus 14 per cent respectively ( P = 0·039). The mean(s.d.) comprehensive complication index was higher in the OLR group, although the difference was not statistically significant (26·7(16·6) versus 18·3(8·0) in the LLR group; P = 0·108). The mean(s.d.) duration of required analgesia and the median (range) duration of postoperative hospital stay were significantly shorter in the LLR group: 3·0(1·1) days versus 1·6(0·8) days in the OLR group ( P < 0·001), and 6 (3-44) versus 4 (1-11) days ( P < 0·001), respectively. The 3-year recurrence-free survival rates for patients with hepatocellular carcinoma (37 per cent for OLR versus 30 per cent for LLR; P = 0·534) and those with colorectal liver metastases (36 versus 36 per cent respectively; P = 0·440) were not significantly different between the groups. Conclusion LLR of tumours in PS segments is feasible in selected patients. LLR is associated with fewer complications and does not compromise survival compared with OLR. [ABSTRACT FROM AUTHOR]

The main idea of the two presented experiments is to study the decay of resonances in 24Mg at excitation energies above the 12C+12C decay threshold, in the astrophysical energy region of interest. The measurement of the 12C(16O,α)24Mg* reaction was performed at INFN-LNS in Catania. Only the α+20Ne decay channel of 24Mg is presented here, because it was a motivation for conducting a new experiment, a study of the4He(20Ne,4He)20Ne reaction, performed at INFN-LNL in Legnaro. Some preliminary results of this measurement are also presented. [ABSTRACT FROM AUTHOR]

Background: The incidence of hidradenitis suppurativa (HS) is still not fully established with only a few studies reporting its estimates. Prevalence estimates range from 5:10 000 to 4:100. These extremely large variations could be explained by a combination of factors, including different selection procedures, different diagnostic criteria, and variations in the sex and age distribution of the examined samples. Objectives: To analyze variations between two consecutive Italian Registries on HS. Methods: Data obtained from the second Italian Registry on HS, named 'Italian Registry Hidradenitis Suppurativa (IRHIS) Project 2', are compared to the previous first Italian registry on HS. Results: Data on 944 patients are reported. The more relevant aspects that characterize IRHIS 2 project, in comparison with the previous first Italian Registry on HS, are as follows: (i) the total number of patients, about fourfold higher; (ii) a more uniform national geographic distribution of the patient population; (iii) a larger number of dermatology units involved; (iv) a larger number of items considered in the data collection; (v) 6 years of difference between the onset of the two registries (2009–2013 vs. 2015–2019). Comparing data of the two registries, there are no statistically significant differences in terms of age at the time of the visit, gender, BMI, smoking habits, age at onset and age at first diagnosis by physician. Interestingly, the mean Sartorius score in the IRHIS project 2 (58.8) was significantly lower compared to the first Italian Registry (78.4). Conclusions: The importance of the registries, at both national and international levels, in collecting useful real‐life data is confirmed by these two Italian projects. [ABSTRACT FROM AUTHOR]

The paper describes a few practical methods for the analysis of data obtained by standard thin-thick silicon detector telescopes used in nuclear reaction measurements. The addressed issues are: 1) improvement in double-sided silicon strip detector (DSSSD) calibration based on the fact that each event is registered twice, both in horizontal and vertical strips, 2) improvements in particle identification and 3) simplified mapping of the non-uniformity of the thin detector, without a dedicated measurement of the thickness. The proposed procedures are applied on experimental data obtained for 30MeV Li beam induced reactions on LiF and C targets, studied with a detection setup consisting of four telescopes placed at different angles and distances. The proposed methods aim at quicker and more reliable calibration and particle identification. [ABSTRACT FROM AUTHOR]

In this work we report on the development of back-gated carbon nanotube-field effect transistors (CNT-FETs), with CNT layers playing the role of the channel, and on their electrical characterisation for sensing applications. The CNTs have been deposited by electrophoresis on an interdigitated electrode region created on a SiO2/Si substrate. Different kinds of CNTs have been used (MWCNTs by arc discharge in liquid nitrogen and MWCNTs by chemical vapour deposition, CVD) and the electrical characterisation of the devices was performed in a NH3- and NO2-controlled environment. Preliminary data have shown an increase in the channel resistance under NH3 exposure, whereas a decrease is observed after exposure to NO2, and the sensitivity to each gas depends on the kind of CNTs used for the device. Furthermore, the defect formation by Si ion implantation on CNTs was investigated by high-resolution transmission electron microscopy (TEM) and Raman analysis. The behaviour observed for the different devices can be explained in terms of the interaction between structural or chemical defects in CNTs and the gas molecules. [ABSTRACT FROM AUTHOR]

Over the last twenty years, there has been a renewed interest in nuclear fragmentation studies for both hadrontherapy applications and space radiation protection. In both fields, fragmentation cross sections are needed to predict the effects of the ions nuclear interactions within the patient's and the astronaut's body. Indeed, the Monte Carlo codes used in planning tumor treatments and space missions must be tuned and validated by experimental data. However, only a limited set of fragmentation cross sections are available in literature, especially at Fermi energies. Therefore, we have studied the production of secondary fragments in the 12C+ 12C and 12C+ 197Au reactions at 62 AMeV. In this work, the measured 4He cross sections angular distributions at four selected angles are presented and compared. [ABSTRACT FROM AUTHOR]

The quasi-elastic scattering angular distribution of the collision 11Be + 64Zn was measured and compared with the elastic scattering angular distribution for its core, the 10Be nucleus on the same target. Optical model and continuum-discretized coupled-channel calculations of the 11Be+64Zn reaction were performed in order to interpret the effect of coupling with the break-up channels on the measured cross-sections. [ABSTRACT FROM AUTHOR]

Nuclear fragmentation measurements are necessary when using heavy-ion beams in hadrontherapy to predict the effects of the ion nuclear interactions within the human body. Moreover, they are also fundamental to validate and improve the Monte Carlo codes for their use in planning tumor treatments. Nowadays, a very limited set of carbon fragmentation cross sections are being measured, and in particular, to our knowledge, no double-differential fragmentation cross sections at intermediate energies are available in the literature. In this work, we have measured the double-differential cross sections and the angular distributions of the secondary fragments produced in the 12C fragmentation at 62 A MeV on a thin carbon target. The experimental data have been used to benchmark the prediction capability of the GEANT4 Monte Carlo code at intermediate energies, where it was never tested before. In particular, we have compared the experimental data with the predictions of two GEANT4 nuclear reaction models: the Binary Light Ions Cascade and the Quantum Molecular Dynamic. From the comparison, it has been observed that the Binary Light Ions Cascade approximates the angular distributions of the fragment production cross sections better than the Quantum Molecular Dynamic model. However, the discrepancies observed between the experimental data and the Monte Carlo simulations lead to the conclusion that the prediction capability of both models needs to be improved at intermediate energies [ABSTRACT FROM AUTHOR]

Multi-wall carbon nanotubes (MWCNTs) produced by the arc discharge between two graphite rods in liquid nitrogen have been investigated with the use of Raman spectroscopy and transmission electron microscopy (TEM). The effects of the applied voltage on the structural properties of the produced MWCNTs have been observed, in particular, as it concerns the size of the innermost and outermost diameters. The apparent discrepancies observed between the Raman and TEM results are explained through the observation of a selective response of the MWCNTs to the excitation laser energy in Raman spectroscopy, similar to the case of single-wall CNTs. Electronic structure calculations correlate such behavior with optical transitions, in the presence of strong electronic localizations, spatially confined in a few neighboring walls. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The 8Li elastic scattering on a 4He gas target was studied by means of the Inverse Kinematic Thick Target scattering method (TTIK) in order to investigate cluster configurations in excited states of 12B. A 8Li beam, at Ec.m. = 10.2 MeV, was provided by the EXCYT radioactive beam facility at Catania. The beam, while passing through the helium thick target decreases its energy, thus exploring the 8Li-α center-of-mass energy range 2.7 MeV≤ECM ≤9.6 MeV. Four ΔE-E silicon detector telescopes were used to detect the recoiling alpha particles. The time interval between the 8Li passing through a micro-channel plate foil, placed at the entrance of the chamber, and the detection of the α particles by the ΔE detectors was also measured. The time measurement allows to disentangle elastic from reactions events, otherwise impossible from energy measurements. This can be considered as an improvement of the TTIK method. In this paper the used experimental technique and the obtained preliminary results will be presented. [ABSTRACT FROM AUTHOR]

In this contribution, results concerning different reaction channels for the collisions induced by the three Be isotopes, 9,10,11Be, on a 64Zn target at energies around the Coulomb barrier will be presented. The experiments with the radioactive 10,11Be beams were performed at REX-ISOLDE (CERN) whereas the experiment with the stable weakly bound 9Be beam was performed at LNS Catania. Elastic scattering angular distributions have been measured for the three systems 9,10,11Be + 64Zn at the same center of mass energy. The angular distributions were analyzed with optical potentials and reaction cross sections were obtained from optical model calculations, performed with the code PTOLEMY. For the 11Be + 64Zn reaction, the break-up angular distribution was also measured. [ABSTRACT FROM AUTHOR]

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The present paper concerns the study of reactions induced by radioactive beams of halo and weakly bound nuclei at energies around and above the Coulomb barrier. The results obtained for the reaction induced by the halo nucleus 6He on 64Zn have been compared with the results for the reaction induced by 4He on the same target. The results of the reaction induced by the weakly bound unstable 13N on the weakly bound 9Be have been compared with those for the reaction 10B + 12C. [ABSTRACT FROM AUTHOR]