Energy chirp measurements by means of an RF deflector: a case study the gamma beam source LINAC at ELI-NP

RF Deflector (RFD) based measurements are widely used in high–brightness electron LINAC around the world in order to measure the ultra–short electron bunch length. The RFD provides a vertical kick to the particles of the electron bunch according to their longitudinal positions. In this paper, a measurement technique for the bunch length and other bunch proprieties, based on the usage of an RFD, is proposed. The basic idea is to obtain information about the bunch length, energy chirp, and energy spread from vertical spot size measurements varying the RFD phase, because they add contributions on this quantity. The case study is the Gamma Beam System (GBS), the Compton Source being built in the Extreme Light Infrastructure–Nuclear Physics (ELI–NP) facility. The ELEctron Generation ANd Tracking (ELEGANT) code is used for tracking the particles from RFD to the measurement screen

Effect of electric load and dual atmosphere on the properties of an alkali containing diopside-based glass sealant for solid oxide cells

© 2019 Elsevier B.V. All rights reserved.A new alkali-containing diopside based glass-ceramic sealant for solid oxide cells was synthesized, characterized and tested. The composition was designed to match the coefficient of thermal expansion (CTE) of Crofer22APU interconnect. The sealant has a glass transition temperature of 600°C, a crystallization peak temperature of 850°C and a maximum shrinkage temperature of 700°C, thus suggesting effective densification prior to crystallization. The CTE of the glass-ceramic is 11.5 10-6 K-1, a value which is compatible with the CTE for Crofer22APU stainless steel. Crofer22APU/glass-ceramic/Crofer22APU joined samples were tested in simulated real-life operating conditions at 800°C in dual atmosphere under an applied voltage, monitoring the electrical resistivity. The effect of two different applied voltages (0.7V and 1.3V) was evaluated. A voltage of 1.3V led to a rapid decrease in the electrical resistivity during the test;such a drop was due to the formation of Cr2O3 “bridges” that connected the two Crofer22APU plates separated by the sealant. There was no decrease in the resistivity when a voltage of 0.7V was applied. Instead,resistivity value remained stable at around 105 Ω cm for the 100h test duration. The degradation mechanisms, due to both the alkali content and the applied voltage, are investigated and discussed.Peer reviewe

Kinetics of growth of non-equilibrium fluctuations during thermodiffusion in a polymer solution

Abstract.: A thermal diffusion process occurring in a binary liquid mixture is accompanied by long ranged non-equilibrium concentration fluctuations. The amplitude of these fluctuations at large length scales can be orders of magnitude larger than that of equilibrium ones. So far non-equilibrium fluctuations have been mainly investigated under stationary or quasi-stationary conditions, a situation that allows to achieve a detailed statistical characterization of their static and dynamic properties. In this work we investigate the kinetics of growth of non-equilibrium concentration fluctuations during a transient thermodiffusion process, starting from a configuration where the concentration of the sample is uniform. The use of a large molecular weight polymer solution allows to attain a slow dynamics of growth of the macroscopic concentration profile. We focus on the development of fluctuations at small wave vectors, where their amplitude is strongly limited by the presence of gravity. We show that the growth rate of non-equilibrium fluctuations follows a power law Rf(q,t) 1d1t as a function of time, without any typical time scale and independently of the wave vector. We formulate a phenomenological model that allows to relate the rate of growth of non-equilibrium fluctuations to the growth of the macroscopic concentration profile in the absence of arbitrary parameters

Optical issues for the diagnostic stations for the ELI-NP compton gamma source

A high brightness electron Linac is being built in the Compton Gamma Source at the ELI Nuclear Physics facility in Romania. To achieve the design luminosity, a train of 32 bunches, 16 ns spaced, with a nominal charge of 250 pC will collide with the laser beam in the interaction point. Electron beam spot size is measured with optical transition radiation (OTR) profile monitors. In order to measure the beam properties, the optical radiation detecting system must have the necessary accuracy and resolution. This paper deals with the studies of different optic configurations to achieve the magnification, resolution and accuracy in order to measure very small beam (below 30 μm) or to study the angular distribution of the OTR and therefore the energy of the beam. Several configurations of the optical detection line will be studied both with simulation tools (e.g. Zemax) and experimentally. The paper will deal also with the sensibility of optic system (in terms of depth of field, magnification and resolution) to systematic error

Effect of the corn stunt spiroplasma disease on maize production.

Suplemento. Edição dos Abstracts do 10º International Congress of Plant Pathology, Beijing, 2013

Feasibility and results of awake thoracoscopic resection of solitary pulmonary nodules

BACKGROUND: General anesthesia with single-lung ventilation is considered mandatory for thoracoscopic pulmonary resection. We assessed in a randomized study the feasibility and results of awake thoracoscopic resection of solitary pulmonary nodules. METHODS: Between March 2001 and February 2003, 60 patients were randomized into two 30-patients arms: a general anesthesia arm entailing double-lumen intubation and thoracic epidural anesthesia (control group); and an awake arm entailing sole thoracic epidural anesthesia at T4-T5 (awake group). Anesthesia time; operative time; global operating room time; patient satisfaction with the anesthesia and technical feasibility scored into 4 grades (from 1 = poor to 4 = excellent); visual analog pain score (VAS), nursing care (number of patient calls per day), 24 hours changes in arterial oxygenation (DeltaPaO2), and hospital stay were assessed. RESULTS: There was no mortality. There was no difference in technical feasibility between the groups although 2 patients in the awake group required conversion to thoracotomy due to severe adhesions. Other 2 patients in each group required conversion due to unexpected lung cancer requiring lobectomy. Comparisons of awake versus control group results showed that in the awake group, anesthesia satisfaction score was greater (4 vs 3, p = 0.04), whereas DeltaPaO2 (-3 mm Hg vs -6.5 mm Hg, p = 0.002); nursing care (2.5 calls per day vs 4 calls per day, p = 0.0001), and hospital stay (2 days vs 3 days, p = 0.02) were significantly reduced. CONCLUSIONS: In our study, awake thoracoscopic resection of solitary pulmonary nodules proved safely feasible. It resulted in better patient satisfaction, less nursing care and shorter in-hospital stay than procedures performed under general anesthesi

Clinical and psychosocial correlates of post-herpetic neuralgia

Post-herpetic neuralgia is the most challenging and debilitating complication of herpes zoster in the immunocompetent host. Because the effect of treatment is disappointing once the syndrome has developed, it is important to know which factors predict post-herpetic neuralgia occurrence to facilitate selection of herpes zoster patients with a higher risk of developing neuralgia and undertake preventative strategies. The present study aimed at identifying demographic, clinical and psychosocial correlates of post-herpetic neuralgia in a sample of 219 immunocompetent patients, who were examined by dermatologists in private practice in Italy and who completed a questionnaire designed to evaluate their clinical and psychosocial profile at the time of clinical diagnosis of herpes zoster and at a follow-up visit 6 months later. In a univariate analysis, post-herpetic neuralgia was associated significantly with older age, longer duration of prodromal pain, greater acute pain intensity, greater extent of rash, presence of abnormal sensations and use of systemic antiviral therapy. Compared to the values at herpes zoster onset, at the follow-up visit patients with post-herpetic neuralgia presented with similar high mean scores of pain intensity, anxiety and depression and greatly reduced quality of life, whereas patients without neuralgia presented with improved scores. In a multivariate model, older age, greater acute pain intensity, greater extent of rash and longer duration of prodromal pain were independently associated with post-herpetic neuralgia. The results of this study may help physicians to identify patients with a higher risk of developing post-herpetic neuralgia and undertaking preventative strategies

No evidence of family history as a risk factor for herpes zoster in patients with post-herpetic neuralgia

Little is known about reactivation of latent varicella zoster virus as herpes zoster in individuals with no underlying immunosuppression. Risk factors include age, sex, ethnicity, exogenous boosting of immunity from varicella contacts, underlying cell-mediated immune disorders, mechanical trauma, psychological stress, and immunotoxin exposure. An association between herpes zoster and family history of zoster has been proposed. A case-control study involving patients affected by post-herpetic neuralgia, which usually follows more severe acute herpes zoster, was performed. The patients with post-herpetic neuralgia were enrolled at the Pain Clinic of the Policlinico Tor Vergata in Rome, Italy, within 1 year from the onset of acute zoster. The controls matched for sex and age were chosen among healthy subjects without a history of herpes zoster presenting at the Internal Medicine Outpatient Clinic for hypertension in the same time period. All the participants in the study gave informed consent and were interviewed by medically trained and blinded investigators using a questionnaire. Similar proportions of the patients and the controls reported a family history of herpes zoster irrespective of the degree of relationship, i.e., 17.4% and 18.2%, respectively, by analyzing only the first-degree relatives [RR 1.03 (CI 95%: 0.78-1.37)], and 28.4% and 29.6%, respectively, by analyzing the total number of relatives [RR 1.03 (CI 95%: 0.81-1.31)]. Further and larger prospective cohort studies are needed to ascertain whether a family history of herpes zoster is really an independent predictor of zoster in different geographical settings

Sonic hedgehog medulloblastoma cancer stem cells mirnome and transcriptome highlight novel functional networks

Molecular classification has improved the knowledge of medulloblastoma (MB), the most common malignant brain tumour in children, however current treatments cause severe side effects in patients. Cancer stem cells (CSCs) have been described in MB and represent a sub population characterised by self-renewal and the ability to generate tumour cells, thus representing the reservoir of the tumour. To investigate molecular pathways that characterise this sub population, we isolated CSCs from Sonic Hedgehog Medulloblastoma (SHH MB) arisen in Patched 1 (Ptch1) heterozygous mice, and performed miRNA-and mRNA-sequencing. Comparison of the miRNA-sequencing of SHH MB CSCs with that obtained from cerebellar Neural Stem Cells (NSCs), allowed us to obtain a SHH MB CSC miRNA differential signature. Pathway enrichment analysis in SHH MB CSCs mirnome and transcriptome was performed and revealed a series of enriched pathways. We focused on the putative targets of the SHH MB CSC miRNAs that were involved in the enriched pathways of interest, namely pathways in cancer, PI3k-Akt pathway and protein processing in endoplasmic reticulum pathway. In silico analysis was performed in SHH MB patients and identified several genes, whose expression was associated with worse overall survival of SHH MB patients. This study provides novel candidates whose functional role should be further investigated in SHH MB

Gabapentin and pregabalin for the acute post-operative pain management. A systematic-narrative review of the recent clinical evidences

Background: Gabapentin and pregabalin inhibit Ca2+ currents via high-voltage-activated channels containing the α2δ-1 subunit, reducing neurotransmitter release and attenuating the postsynaptic excitability. They are antiepileptic drugs successfully used also for the chronic pain treatment. A large number of clinical trials indicate that gabapentin and pregabalin could be effective as postoperative analgesics. This systematic-narrative review aims to analyse the most recent evidences regarding the effect of gabapentinoids on postoperative pain treatment. Methods: Medline, The Cochrane Library, EMBASE and CINHAL were searched for recent (2006-2009) randomized clinical trials (RCTs) of gabapentin-pregabalin for postoperative pain relief in adults. Quality of RCTs was evaluated according to Jadad method. Visual analogue scale (VAS), opioid consumption and side-effects (nausea, vomiting, dizziness and sedation) were considered the most important outcomes. Results: An overall of 22 gabapentin (1640 patients), 8 pregabalin (707 patients) RCTs and seven meta-analysis were involved in this review. Gabapentin provided better post-operative analgesia and rescue analgesics sparing than placebo in 6 of the 10 RCTs that administered only pre-emptive analgesia. Fourteen RCTs suggested that gabapentin did not reduce PONV when compared with placebo, clonidine or lornoxicam. Pregabalin provided better post-operative analgesia and rescue analgesics sparing than placebo in two of the three RCTs that evaluated the effects of pregabalin alone vs placebo. Four studies reported no pregabalin effects on preventing the PONV. Conclusion: Gabapentin and pregabalin reduce pain and opioid consumption after surgery in confront with placebo, but comparisons with other standard post-operative regimens are not sufficient. Gabapentin and pregabalin seem not to have any influence on the prevention of PONV