Clean room Norme interne OAS Bologna

Il presente documento è stato elaborato da parte dei Responsabili della camera bianca ed elenca le regole di buona pratica nella disciplina e nel vestiario congrue al laboratorio secondo le indicazioni ISO nel contesto dell’infrastruttura Camera Pulita ubicata al IV piano dell’edificio OAS-Bologna all’interno dell’area CNR

Twin shaping filter technique for signals compensation in CZT detectors grown by the vertical bridgman method

CdTe/CdZnTe is a consolidated material to realize detectors for a large variety of applications, such as medical, industrial, and space research. An Italian collaboration, involving the CNR/IMEM and INAF/IASF institutes, was born some years ago with the aim to develop a national capability to produce CZT detectors starting from the material growth to the final detection device. Some important features of these detectors (pulse height, energy resolution, photopeak efficiency) are affected by the charge collection efficiency: the low mobility of the charge carriers (particularly the holes) and trapping/detrapping phenomena can degrade the CdTe/CZT detectors response, depending on the distance between the charge formation position and the collecting electrodes. Several efforts have been made to improve the detection efficiency as well as the energy resolution, using both the optimization of the electrode geometry (drift strip technique, coplanar-grid, small pixel effect) and pulse height compensation methods to overcome the hole trapping problem. We have studied a bi-parametric method that uses a twin pulse shaping active filter to analyze the same signal: one slow, which is proportional to the energy of the photon, and one fast, which depends on the position of the interaction with respect to the collecting electrode. The experimental results obtained with the application of this bi-parametric technique on planar CZT detectors of good quality grown by the Vertical Bridgman method at CNR/IMEM are presented as a function of the bias voltage, photon energy and shaping time pairs

Semantics-Aware Autoencoder

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Signal compensation in CZT detectors grown by the Vertical Bridgman method using a twin-shaping filter technique

CdTe/CZT is now a material consolidated for the detectors realization operating at room temperature, which find a large variety of applications in astrophysics, medical imaging and security. An Italian collaboration, involving the CNR/IMEM and INAF/IASF institutes, was born several years ago with the aim to develop a national capability to produce CZT detectors starting from the material growth to the final detection device. The collection efficiency of the charge carriers affects some important features of these detectors, such as the pulse height, energy resolution, photopeak efficiency. In fact the low mobility of the charge carriers (particularly the holes) and trapping/detrapping phenomena can degrade the CdTe/CZT detector response, depending on the distance between the charge formation position and the collecting electrodes. Two kinds of techniques can be used to improve both the collection efficiency and the energy resolution, based on the optimization of the electrode geometry and/or signal compensation methods. We have implemented a biparametric method that uses a twin pulse shaping active filter to analyze the same signal from the detector: one “slow”, which is proportional to the energy of the incident photon, and one “fast”, which depends on the position of the interaction with respect to the collecting electrode. We present this biparametric technique applied on planar CZT detectors grown by the Vertical Bridgman method at CNR/IMEM (Parma), the experimental results obtained as a function of the bias voltage, photon energy, shaping time pairs and the compensated spectra

Soluble beta amyloid evokes alteration in brain norepinephrine levels: role of nitric oxide and interleukin-1

Strong evidence showed neurotoxic properties of beta amyloid (Aβ) and its pivotal role in the Alzheimer's disease (AD) pathogenesis. Beside, experimental data suggest that Aβ may have physiological roles considering that such soluble peptide is produced and secreted during normal cellular activity. There is now suggestive evidence that neurodegenerative conditions, like AD, involve nitric oxide (NO) in their pathogenesis. Nitric oxide also possess potent neuromodulatory actions in brain regions, such as prefrontal cortex (PFC), hippocampus (HIPP), and nucleus accumbens (NAC). In the present study, we evaluated the effect of acute Aβ injection on norepinephrine (NE) content before and after pharmacological manipulations of nitrergic system in above mentioned areas. Moreover, effects of the peptide on NOS activity were evaluated. Our data showed that 2 h after i.c.v. soluble Aβ administration, NE concentrations were significantly increased in the considered areas along with increased iNOS activity. Pre-treatment with NOS inhibitors, 7-Nitroindazole (7-NI), and N6-(1-iminoethyl)-L-lysine-dihydrochloride (L-NIL), reversed Aβ-induced changes. Ultimately, pharmacological block of interleukin1 (IL-1) receptors prevented NE increase in all brain regions. Taken together our findings suggest that NO and IL-1 are critically involved in regional noradrenergic alterations induced by soluble Aβ injection

Twin-Shaping Filter Technique Applied to CZT Detectors

CdTe/CdZnTe is an attractive and consolidated material with which to realize detectors with good efficiency and energy resolution, operating at room temperature for a large variety of applications such as astrophysics, medical imaging and security. However, this type of material suffers from the low mobility of the charge carriers (particularly the holes), which are trapped and so degrade the detector response in terms of charge collection efficiency, energy resolution and photopeak efficiency. The response of a planar CdTe/CdZnTe detector, which depends on the distance between the charge formation position and the collecting electrodes, can be improved by using two kinds of techniques, based on the optimization of the electrode geometry and/or signal compensation methods. We are studying the feasibility and the reliability of a biparametric method that uses a twin pulse shaping active filter to analyze each signal from the detector twice: one “Slow”, which is proportional to the energy of the incident photon, and one “Fast”, which depends on the position of the interaction with respect to the collecting electrode. In this paper we describe the bi-parametric technique applied to planar CdZnTe detectors grown by CNR/IMEM and to Spectrometer Grade detectors. We report the experimental results in terms of energy resolution, peak-to valley ratio and photopeak efficiency, as well as the compensated spectra obtained as a function of the bias voltage, photon energy and shaping time pairs. We also report the results obtained by using a CdZnTe drift strip detector. Furthermore, this technique could be implemented in an array of detectors, whose front-end electronics is composed of ASICs, where the shaping time can be selected for each channel, like the RENA-3 IC (NOVA R&D)