OTR based measurements for ELI-NP Gamma Beam Source

The Gamma Beam Source (ELI-NP-GBS) machine is an advanced source of up to ≈20 MeV Gamma Rays based on Compton back-scattering, i.e. collision of an intense high power laser beam and a high brightness electron beam with maximum kinetic energy of about 720 MeV. The Linac will provide trains of 32 electron bunches in each RF pulse, separated by 16.1 ns; each bunch has a charge of 250 pC . The goal of my work is to propose a layout for a distributed energy measurement along the ELI-NP-GBS machine: this will be useful during the commissioning stage of the machine in order to verify the correct functionality of the newly design C-Band accelerating structures, due to the fact that there are OTR screens after each accelerating module. Furthermore, I have studied the feasibility of bunch by bunch energy measurement using a gated camera system

Impact of soil management on the functional activity of microbial communities associated to cork oak rhizosphere

The microbial ecology of cork oak rhizosphere was investigated using the Biolog community level physiological profile (CLPP) that provides a unique metabolic fingerprint helpful for the characterization of complex microbial communities. Microbial populations from the rhizosphere of cork oak plants growing at three different sites within the same area were characterized using CLPP and compared. The sites were distinguished by a different soil management under the tree cover and, in general terms, by a different anthropogenic impact. The comparison of metabolic fingerprints of the different microbial populations showed the existence of a relationship between general microbial activity and functional biodiversity in the rhizosphere and the level of anthropogenic impact. Particularly the presence of grazing animals, soil tillage and fire could be identified as the main factors affecting both the general microbial activity and the structure of microbial populations from cork oak rhizospheres

Synthetic Bone Substitutes and Mechanical Devices for the Augmentation of Osteoporotic Proximal Humeral Fractures: A Systematic Review of Clinical Studies

Different augmentation techniques have been described in the literature in addition to the surgical treatment of proximal humeral fractures. The aim of this systematic review was to analyze the use of cements, bone substitutes, and other devices for the augmentation of proximal humeral fractures

Longitudinal and Transverse Wakefields Simulations and Studies in Dielectric-Coated Circular Waveguides

In recent years, there has been a growing interest and rapid experimental progress on the use of e.m. fields produced by electron beams passing through dielectric-lined structures and on the effects they might have on the drive and witness bunches. Short ultra-relativistic electron bunches can excite very intense wakefields, which provide an efficient acceleration through the dielectric wakefield accelerators (DWA) scheme with higher gradient than that in the conventional RF LINAC. These beams can also generate high power narrow band THz coherent Cherenkov radiation. These high gradient fields may create strong instabilities on the beam itself causing issues in plasma acceleration experiments (PWFA), plasma lensing experiments and in recent beam diagnostic applications. In this work we report the results of the simulations and studies of the wakefields generated by electron beams at different lengths and charges passing on and off axis in dielectric-coated circular waveguides. We also propose a semi-analytical method to calculate these high gradient fields without resorting to time consuming simulations

A Python approach for GRB afterglow analysis: sAGa (Software for AfterGlow Analysis)

This technical note describes a fully self-consistent code in Python – called sAGa (Software for AfterGlow Analysis) – to cope with the complex landscape of GRB afterglows. sAGa adds up to other pre-existing broadband fitting tools in the literature and provides an independent check, emphasising the broadband study of GRB afterglows over the last two decades. This code aims to model GRB afterglow data within a self-consistent physically grounded picture. Built adopting a Bayesian approach, all the data set, from radio to gamma-rays, is modelled. By-products are plots of spectra and light-curves, and computation of the break frequencies and normalisations as a function of the shock microphysical parameters, such as the power-law index of the electron energy distribution, the fractions of the blastwave energy delivered to relativistic electrons and magnetic fields, and other parameters such as the kinetic energy of the explosion and the density of the circumburst medium (CBM). Dust extinction of optical along the sightline and scintillation in radio frequencies are also accounted for. sAGa has been successfully tested on the broadband data of the afterglows of GRB120521C, GRB090423, and GRB050904. Our results are consistent with those reported in the literature within 2 sigma. Moreover, the values of the power-law index of the electron energy distribution obtained from sAGa analysis are compatible with the inferences based on the lines of reasoning based on the observation of the optical/X-ray spectra

Measurements with the ELI-NP cavity Beam Position Monitor Read-out Electronics at FLASH

The Extreme Light Infrastructure - Nuclear Physics Gamma Beam System (ELI-NP GBS) will be installed and commissioned starting within the next year in Magurele, Romania. It will generate gamma beam through Compton back-scattering of a recirculated laser and a multi-bunch electron beam, produced by a 720 MeV LINAC. In order to obtain bunch by bunch position measurements, four cavity beam position monitors (cBPM) near the two interaction points are foreseen. Extensive tests on the cBPM readout electronics, recently developed by Instrumentation Technologies and acquired for ELI-NP GBS, were performed in laboratory at INFN-LNF and at FLASH in DESY, during the user operation. In the latter case, three cBPMs installed along the LINAC, with similar features as the ones of ELI-NP GBS, were used as measuring devices and signal sources for the read-out electronics under test. We present here the measurements collected and the related analysis, with a particular focus on the beam position measurement resolution

Thermal simulations for optical transition radiation screen for Eli-NP compton gamma source

The ELI-NP GBS (Extreme Light Infrastructure-Nuclear Physics Gamma Beam Source) is a high brightness elec-tron LINAC that is being built in Romania. The goal for this facility is to provide high luminosity gamma beam through Compton Backscattering. A train of 32 bunches at 100Hz with a nominal charge of 250pC is accelerated up to 740 MeV. Two interaction points with an IR Laser beam produces the gamma beam at different energies. In order to measure the electron beam spot size and the beam proper-ties along the train, the OTR screens must sustain the ther-mal and mechanical stress due to the energy deposited by the bunches. This paper is an ANSYS study of the issues due to the high quantity of energy transferred to the OTR screen. They will be shown different analysis, steady-state and thermal transient analysis, where the input loads will be the internal heat generation equivalent to the average power, deposited by the ELI-GBS beam in 512 ns, that is the train duration. Each analyses will be followed by the structural analysis to investigate the performance of the OTR materi

Improvement in Hemodynamic Responses to Metaboreflex Activation after One Year of Training in Spinal Cord Injured Humans

Spinal cord injured (SCI) individuals show an altered hemodynamic response to metaboreflex activation due to a reduced capacity to vasoconstrict the venous and arterial vessels below the level of the lesion. Exercise training was found to enhance circulating catecholamines and to improve cardiac preload and venous tone in response to exercise in SCI subjects. Therefore, training would result in enhanced diastolic function and capacity to vasoconstrict circulation. The aim of this study was to test the hypothesis that one year of training improves hemodynamic response to metaboreflex activation in these subjects. Nine SCI individuals were enrolled and underwent a metaboreflex activation test at the beginning of the study (T0) and after one year of training (T1). Hemodynamics were assessed by impedance cardiography and echocardiography at both T0 and T1. Results show that there was an increment in cardiac output response due to metaboreflex activity at T1 as compared to T0 (545.4 ± 683.9 mL · min(-1) versus 220.5 ± 745.4 mL · min(-1), P < 0.05). Moreover, ventricular filling rate response was higher at T1 than at T0. Similarly, end-diastolic volume response was increased after training. We concluded that a period of training can successfully improve hemodynamic response to muscle metaboreflex activation in SCI subjects

Arthroscopically assisted reduction and internal fixation (ARIF) versus open reduction and internal fixation (ORIF) for lateral tibial plateau fractures: a comparative retrospective study

Background: This study aims to explore if the arthroscopically assisted reduction and internal fixation (ARIF) technique is superior to the traditional open reduction and internal fixation (ORIF) technique in the treatment of tibial lateral plateau fractures. Methods: Forty patients with tibial plateau fractures (Schatzker type I–III) treated with ARIF or ORIF from 2012 to 2017 were included in this retrospective study. All patients received pre-operative radiographs and CT scans. The patients were divided into two groups (ARIF or ORIF). All patients had a minimum follow-up of 12 months and an average follow-up of 44.4 months. The clinical and radiographic outcomes were evaluated according to the Knee Society Score (KSS) and the modified Rasmussen radiological score. Results: Satisfactory clinical and radiological results were found in 39 out of 40 (97.5%) patients. KSS and modified Rasmussen radiological score were significantly better in ARIF group. The mean KSS was 92.37 (± 6.3) for the ARIF group and 86.29 (± 11.54) for the ORIF group (p &lt; 0.05). The mean modified Rasmussen radiographic score was 8.42 (± 2.24) for the ARIF group and 7.33 (± 1.83) for the ORIF group (p = 0.104). Worst clinical and radiological results were related to concomitant intra-articular lesions (p &lt; 0.05). Meniscal tears were found and treated in 17 out of 40 (42.5%) patients. The overall complication rate was 10%. Conclusions: Both ARIF and ORIF provided a satisfactory outcome for the treatment of Schatzker I–III tibial plateau fractures. However, ARIF led to better clinical results than ORIF. No statistically significant differences were found in perioperative complications, radiological results, and post-traumatic knee osteoarthritis. Level of evidence: Level II