Applications of three-dimensional carbon nanotube

In this paper, we show that it is possible to synthesize carbon-based three-dimensional networks by adding sulfur, as growth enhancer, during the synthesis process. The obtained material is self-supporting and consists of curved and interconnected carbon nanotubes and to lesser extent of carbon fibers. Studies on the microstructure indicate that the assembly presents a marked variability in the tube external diameter and in the inner structure. We study the relationship between the observed microscopic properties and some potential applications. In particular, we show that the porous nature of the network is directly responsible for the hydrophobic and the lipophilic behavior. Moreover, we used a cut piece of the produced carbon material as working electrode in a standard electrochemical cell and, thus, demonstrating the capability of the system to respond to incident light in the visible and near-ultraviolet region and to generate a photocurrent

Multi-GeV Electron Spectrometer

The advance in laser plasma acceleration techniques pushes the regime of the resulting accelerated particles to higher energies and intensities. In particular the upcoming experiments with the FLAME laser at LNF will enter the GeV regime with almost 1pC of electrons. From the current status of understanding of the acceleration mechanism, relatively large angular and energy spreads are expected. There is therefore the need to develop a device capable to measure the energy of electrons over three orders of magnitude (few MeV to few GeV) under still unknown angular divergences. Within the PlasmonX experiment at LNF a spectrometer is being constructed to perform these measurements. It is made of an electro-magnet and a screen made of scintillating fibers for the measurement of the trajectories of the particles. The large range of operation, the huge number of particles and the need to focus the divergence present unprecedented challenges in the design and construction of such a device. We will present the design considerations for this spectrometer and the first results from a prototype.Comment: 7 pages, 6 figures, submitted to NIM

Frequency-modulated electromagnetic neural stimulation (FREMS) as a treatment for symptomatic diabetic neuropathy: results from a double-blind, randomised, multicentre, long-term, placebo-controlled clinical trial

AIMS/HYPOTHESIS: The aim was to evaluate the efficacy and safety of transcutaneous frequency-modulated electromagnetic neural stimulation (frequency rhythmic electrical modulation system, FREMS) as a treatment for symptomatic peripheral neuropathy in patients with diabetes mellitus. METHODS: This was a double-blind, randomised, multicentre, parallel-group study of three series, each of ten treatment sessions of FREMS or placebo administered within 3 weeks, 3 months apart, with an overall follow-up of about 51 weeks. The primary endpoint was the change in nerve conduction velocity (NCV) of deep peroneal, tibial and sural nerves. Secondary endpoints included the effects of treatment on pain, tactile, thermal and vibration sensations. Patients eligible to participate were aged 18-75 years with diabetes for ≥ 1 year, HbA(1c) <11.0% (97 mmol/mol), with symptomatic diabetic polyneuropathy at the lower extremities (i.e. abnormal amplitude, latency or NCV of either tibial, deep peroneal or sural nerve, but with an evocable potential and measurable NCV of the sural nerve), a Michigan Diabetes Neuropathy Score ≥ 7 and on a stable dose of medications for diabetic neuropathy in the month prior to enrolment. Data were collected in an outpatient setting. Participants were allocated to the FREMS or placebo arm (1:1 ratio) according to a sequence generated by a computer random number generator, without block or stratification factors. Investigators digitised patients' date of birth and site number into an interactive voice recording system to obtain the assigned treatment. Participants, investigators conducting the trial, or people assessing the outcomes were blinded to group assignment. RESULTS: Patients (n = 110) with symptomatic neuropathy were randomised to FREMS (n = 54) or placebo (n = 56). In the intention-to-treat population (50 FREMS, 51 placebo), changes in NCV of the three examined nerves were not different between FREMS and placebo (deep peroneal [means ± SE]: 0.74 ± 0.71 vs 0.06 ± 1.38 m/s; tibial: 2.08 ± 0.84 vs 0.61 ± 0.43 m/s; and sural: 0.80 ± 1.08 vs -0.91 ± 1.13 m/s; FREMS vs placebo, respectively). FREMS induced a significant reduction in day and night pain as measured by a visual analogue scale immediately after each treatment session, although this beneficial effect was no longer measurable 3 months after treatment. Compared with the placebo group, in the FREMS group the cold sensation threshold was significantly improved, while non-significant differences were observed in the vibration and warm sensation thresholds. No relevant side effects were recorded during the study. CONCLUSIONS/INTERPRETATION: FREMS proved to be a safe treatment for symptomatic diabetic neuropathy, with immediate, although transient, reduction in pain, and no effect on NCV. TRIAL REGISTRATION: ClinicalTrials.gov NCT01628627. FUNDING: The clinical trial was sponsored by Lorenz Biotech (Medolla, Italy), lately Lorenz Lifetech (Ozzano dell'Emilia, Italy)

Brazing alloys characterization for EU-DEMO Divertor Target

In the framework of the roadmap of the DEMO reactor design pursued by the EUROfusion Programme, R&amp;D activities have been promoted for the technological development of Plasma Facing Components (PFCs). Dedicated research activity has been undertaken at ENEA to support the development of technological solutions for the monoblock-pipe joining in order to reduce the use of materials having high activation and/or a degradation under neutron irradiation. For this purpose, a preliminary brazing alloy screening was carried out: a total of seven brazing alloys were identified and tested (i.e. Gemco, Nicuman23, TiCuNi, CuTiZrNi and three alloys with different percentages of Cu and Ge). For each brazing alloy, a wettability test on joint base materials (i.e., W and Cu) was performed. Then, three samples were fabricated joining tungsten monoblocks, without Cu interlayer, on a W fiber-reinforced Cu composite cooling pipe; other three samples were realized joining W monoblocks, with and without Cu interlayer on standard ITER-grade CuCrZr pipes. Non-destructive Ultrasonic Testing (UT) examinations were performed on each sample and showed that the monoblocks surface was not fully attached to Wf-Cu pipes; as regard the samples with CuCrZr pipes, excellent results have been achieved both in the case with and without Cu interlayer. From the results, Gemco seems to be the most promising commercial alloy among the tested ones, thanks to its low amount of Nickel and the good joining capabilities

Long-pulse high heat flux testing of tungsten monoblock target mock-ups for investigation of creep fatigue interaction

Divertor components for ITER and even beyond will be subjected to cyclic steady state heat loads with a duration of several minutes to hours, repeatedly occurring slow transients during reattachment or ramp-up and down, as well as heat loads during ELMs applying a combination of low cycle fatigue and creep as well as high cycle fatigue via thermal shock loads. While for the qualification of components the duration of the fatigue cycles up to now has been kept small, i.e., close to the required time to reach thermal saturation which is 10 s for typical divertor components, creep in these components has not yet been assessed. In this study divertor tungsten monoblock mock-up manufactured via hot radial pressing in the ITER-like geometry consisting of 4 monoblocks and quality checked via ultrasonic testing are exposed to high heat flux loads in the electron beam facility JUDITH 2 using a high temperature cooling circuit with controlled water chemistry. Thereby, cyclic loads up to 1000 cycles with a duration of 10 to 600 s and a power density of 20 MW/m2 were applied, representing strike point loading conditions in DEMO during strike point sweeping scenarios. Each of the tungsten monoblocks is loaded individually providing the possibility to study different scenarios on one single mock-up. The aim is to assess the performance and degradation of performance due to the applied loads, which is supported by characterization via metallography, profilometry, SEM and hardness testing after the high heat flux tests

Clinical characteristics and outcomes of Takotsubo syndrome in patients with chronic obstructive pulmonary disease

Background: takotsubo syndrome (TTS) is an acute heart failure syndrome characterized by a relevant comorbid background, including chronic obstructive pulmonary disease (COPD). However, TTS patients with COPD are still not well characterized. Aim: to describe the clinical characteristics and outcomes of patients with TTS and COPD. Methods: n = 440 TTS patients were dichotomized according to the presence of COPD. Endpoint of the study were in-hospital complications (composite of death, major arrhythmias, cardiogenic shock and acute pulmonary edema), TTS recurrence and long-term mortality at follow-up. Results: mean age of the population was 72±11, 10 % males. COPD prevalence was 16 % (n = 69). On subgroup analysis, patients with COPD were more likely smokers (41 % vs 13 %, p &lt; 0.001), with higher rates of dyspnea and physical triggers at presentation (52 % vs 18 %, p &lt; 0.001 and 52 % vs 32 %, p = 0.001 respectively) and lower left ventricular ejection fraction (36 % vs 39 %, p = 0.035) In-hospital complications were more common in patients with COPD (26 % vs 13 %, p = 0.006), driven by higher rates of acute pulmonary edema (19 % vs 6 %, p &lt; 0.001) and cardiogenic shock (10 % vs 4 %, p = 0.023). At multivariable logistic regression analysis, COPD was independently associated with in-hospital complications occurrence (Odds Ratio 2.10, 95 % CI 1.09–4.05; p = 0.027). At univariable Cox regression analysis COPD was associated with TTS recurrence (Hazard Ratio (HR 9.82, 95 % CI 3.2–30.12; p &lt; 0.001)), at multivariable Cox regression analysis with long-term mortality (HR 2.97, 95 % CI 1.44–6.12; p = 0.003). Conclusion: COPD marks a vulnerable TTS phenotype including higher risk of in-hospital complications, long-term recurrence and mortality

Tuning multi/pluri-potent stem cell fate by electrospun poly(L-lactic acid)-calcium-deficient hydroxyapatite nanocomposite mats

In this study, we investigated whether multipotent (human-bone-marrow-derived mesenchymal stem cells [hBM-MSCs]) and pluripotent stem cells (murine-induced pluripotent stem cells [iPSCs] and murine embryonic stem cells [ESCs]) respond to nanocomposite fibrous mats of poly(L-lactic acid) (PLLA) loaded with 1 or 8 wt % of calcium-deficient nanohydroxyapatite (d-HAp). Remarkably, the dispersion of different amounts of d-HAp to PLLA produced a set of materials (PLLA/d-HAp) with similar architectures and tunable mechanical properties. After 3 weeks of culture in the absence of soluble osteogenic factors, we observed the expression of osteogenic markers, including the deposition of bone matrix proteins, in multi/pluripotent cells only grown on PLLA/d-HAp nanocomposites, whereas the osteogenic differentiation was absent on stem-cell-neat PLLA cultures. Interestingly, this phenomenon was confined only in hBM-MSCs, murine iPSCs, and ESCs grown on direct contact with the PLLA/d-HAp mats. Altogether, these results indicate that the osteogenic differentiation effect of these electrospun PLLA/d-HAp nanocomposites was independent of the stem cell type and highlight the direct interaction of stem cell-polymeric nanocomposite and the mechanical properties acquired by the PLLA/d-HAp nanocomposites as key steps for the differentiation process