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

ANN Modelling to Optimize Manufacturing Process

Neural network (NN) model is an efficient and accurate tool for simulating manufacturing processes. Various authors adopted artificial neural networks (ANNs) to optimize multiresponse parameters in manufacturing processes. In most cases the adoption of ANN allows to predict the mechanical proprieties of processed products on the basis of given technological parameters. Therefore the implementation of ANN is hugely beneficial in industrial applications in order to save cost and material resources. In this chapter, following an introduction on the application of the ANN to the manufacturing process, it will be described an important study that has been published on international journals and that has investigated the use of the ANNs for the monitoring, controlling and optimization of the process. Experimental observations were collected in order to train the network and establish numerical relationships between process-related factors and mechanical features of the welded joints. Finally, an evaluation of time-costs parameters of the process, using the control of the ANN model, is conducted in order to identify the costs and the benefits of the prediction model adopted

Emission measure distribution in loops impulsively heated at the foot-points

This work is prompted by the evidence of sharply peaked emission measure distributions in active stars, and by the claims of isothermal loops in solar coronal observations, at variance with the predictions of hydrostatic loop models with constant cross-section and uniform heating. We address the problem with loops heated at the foot-points. Since steady heating does not allow static loop models solutions, we explore whether pulse-heated loops can exist and appear as steady loops, on a time average. We simulate pulse-heated loops, using the Palermo-Harvard 1-D hydrodynamic code, for different initial conditions corresponding to typical coronal temperatures of stars ranging from intermediate to active ($T \sim 3$--$10 \times 10^6$ K). We find long-lived quasi-steady solutions even for heating concentrated at the foot-points over a spatial region of the order of $\sim 1/5$ of the loop half length and broader.These solutions yield an emission measure distribution with a peak at high temperature, and the cool side of the peak is as steep as $\sim T^{5}$, in contrast to the usual $\sim T^{3/2}$ of hydrostatic models with constant cross-section and uniform heating. Such peaks are similar to those found in the emission measure distribution of active stars around $10^7$ K.Comment: 9 pages, 6 figures, accepted for publication in The Astrophysical Journa

Atypical Fibroxanthoma-Like Amelanotic Melanoma: A Diagnostic Challenge

Atypical fibroxanthoma-like amelanotic melanoma is a very rare variant of melanoma that can, if not correctly recognized and framed, lead to diagnostic errors that can potentially cause problems of extreme relevance to patients. Correct knowledge of this entity and the execution of adequate immunohistochemical investigations are the basic conditions for the correct management of this lesion. We report on a case of atypical fibroxanthoma-like amelanotic melanoma, which clinically simulated a fibrohistiocytic lesion, and which created differential diagnostic problems, and finally, we conduct a short review of the literature

Down regulation of early sea urchin histone H2A gene relies on cis regulative sequences located in the 5’ and 3’ regions and including the enhancer blocker sns

The tandem repeated sea urchin α-histone genes are developmentally regulated by gene-specific promoter elements. Coordinate transcription of the five genes begins after meiotic maturation of the oocyte, continues through cleavage, and reaches its maximum at morula stage, after which these genes are shut off and maintained in a silenced state for the life cycle of the animal. Although cis regulative sequences affecting the timing and the level of expression of these genes have been characterized, much less is known about the mechanism of their repression. Here we report the results of a functional analysis that allowed the identification of the sequence elements needed for the silencing of the α-H2A gene at gastrula stage. We found that important negative regulative sequences are located in the 462 bp sns 5 fragment located in the 3′ region. Remarkably, sns 5 contains the sns enhancer blocking element and the most 3′ H2A codons. In addition, we made the striking observation that inhibition of the anti-enhancer activity of sns, by titration of the binding proteins in microinjected embryos, also affected the capability of sns 5 to down-regulate transgene expression at gastrula stage. A further sequence element essential for repression of the H2A gene was identified upstream of the enhancer, in the 5′ region, and contains four GAGA repeats. Altogether these findings suggest that down-regulation of the α-H2A gene occurs by the functional interaction of the 5′ and 3′ cis sequence elements. These results demonstrate the involvement of a genomic insulator in the silencing of gene expression

Double Tracheoesophageal Fistula and Azygos Lobe

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