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Breast reconstruction is fundamental and urgent for patients in order to avoid future psychological and physical issues. That’s why immediate breast reconstruction has been requested increasingly in the last years. In this study two prosthesis with different structures and properties were compared according the aesthetic appearance (BREAST-Q© was employed) and five complications (seroma, hematoma, infections, dehiscence and red breast syndrome). The overall population was composed by 56 patients: 24 received a Tutomesh prosthesis and 32 received a Surgimend prosthesis. The DMAIC (define, measure, analyse, improve and control) cycle was implemented as a problem-solving strategy of the Six Sigma to compare the prostheses. While statistically significant difference between the two groups wasn’t found according to the overall BREAST-Q© (p-value = 0.674), the number of complications of the two groups resulted statistically different (p-value of chi-square test less than 0.001). Although it is not possible to understand from this study the reasons of the differences between the complications, this research proved that Surgimend and Tutomesh prostheses can be both implanted safely for immediate breast reconstruction since the higher costs of Surgimend could be neutralized with its lower hospitalization compared to Tutomesh. © 2021, Springer Nature Switzerland AG.

The use of NE102A-BaF2 phoswich detector drastically improves the particle identification with respect to BaF2 crystals. To better exploit the possibility of light ion discrimination we have applied digital signal processing to the signals, on-beam collected with NE102A-BaF2 phoswich. We present the results obtained for the heavy ion charge identification (up to Z=50) and light particle mass identification, using digital pulse shape acquisition and a 12-bit, 2 GSample/s sampling analog to digital converter. The results concerning the response of BaF2-plastic phoswich to the reaction products issued at forward angles in the collision of 35.1 MeV/u 124Sn beam on 64Ni target have been obtained at the Superconducting Cyclotron of the Laboratori Nazionali del Sud in Catania.

We have built and tested a computational unit for on-line processing of special algorithms to be embedded in the central processing unit VERSAmodule Eurocard (CPU VME)-crate of the CHIMERA data acquisition system. The computational unit consists of a number of VME digital signal processor (DSP)-based commercial boards delivering 720 MFlops/board.

Biological vision processes are at the basis of many studies in the image-processing field. In this context, neural networks developed by S. Grossberg constitute an interesting approach. The paper presents a novel method for the automatic analysis of scatter plots from CHIMERA experimental data based on Grossberg's pre-attentive neural systems. The design and implementation of a system developed for this purpose are illustrated. The proposed method yields satisfactory results also in very noisy cases.

CHIMERA is a second generation 4/spl pi/ detector for high resolution light particle and fragment measurements in the field of intermediate energy nuclear reactions. An enhanced data acquisition, control and trigger system has been developed to manage the almost 5000 electronic channels of the detector. The data acquisition system is based on a Fast Data Link (FDL) connection between 9U VME crates. The FDL is a highly programmable VME device. It performs data readout and transfer to a destination VME CPU, the FIC8243, running the real time OS9 operating system. Data read and transfer is performed by a fast protocol (Sparse Data Scan) whose performances have been improved introducing the Chained Block Transfer mode (CBLT) technique. Data collected by the CPU are broadcast to analysis work-stations for on-line data analysis and storage. All commands from and to the VME CPU are sent by socket-based network protocols. Complete remote control of the electronic front-end is obtained by a system of client-server applications. A first level event selection and control during readout is made by a trigger system based on a new VME 9U board (MUSE), fully integrated with the FDL readout system.

A commercial two-DSP-based board is the basic unit of the on-line computational and control system under development for the multidetector array CHIMERA. The system design includes a small scale parallel and distributed architecture of PCs and DSP boards. The PCs are used both as host computer and interface between user and network. Each PC can host up to three DSP boards. The system is able to accomplish the on-beam control of CHIMERA, by means of the on-line computation of special algorithms, instead of using the usual techniques of special pulses to be sent off-beam. The physical data, collected and organized in UDP packets by the data acquisition system, are read through a 10 Mbit/s Ethernet network. The PC software, running under Windows NT 4.0, is based on threads and assures the communication and program managing as well as the result presentation. The DSP-software is written in C++ and takes care of the communication with the PC and of the computation of algorithms. The preliminary on beam results for the first three wheels (about 100 telescopes), obtained by employing two biprocessor boards located in the PCI bus of a Pentium MMX PC, are also presented.

CHIMERA (Charged Heavy Ions Mass and Energy Resolving Array), a new 4/spl pi/ detector for charged particles is under development at various sites of the Istituto Nazionale di Fisica Nucleare. This paper describes the new data acquisition system built to handle the signals coming out from the detector with a rate up to 1 kHz on almost 5000 electronic channels. The required average throughput for the system is in the order of the 1 MB/s. The used converters allow double-range conversion on 15 bits, in less than 50 /spl mu/s for all the 64 channels. The FDL link connects the different VME 9U crates performing a programmable hardware readout with a rate up to 100 MB/s. It uses a fast hardware protocol (Sparse Data Scan) to read the data buffers and send them to a FIC 8243 CPU board. A FIC 8243 dual-processor board forwards data (through Ethernet) to the analysis station (266 MHz Digital AlphaStation or Sun Sparcstation). A DLT (Digital Linear Tape) unit connected to analysis station is used to store data. The new data acquisition system has been tested under beam conditions at the Laboratorio Nazionale del Sud (Catania, Italy) and at GANIL (Caen, France).

A digital signal processor (DSP) based two-parameter data acquisition system, connected to two analog-to-digital converters (ADCs) by means of an ad hoc built interface, was developed in order to perform real-time, on-line data processing. The interface, realized with programmable logic devices (PLD); may also work as a table of pre-computed values through which it is possible to carry out a simple analysis on the incoming or outcoming data.

CHIMERA is the only 4 pi-multidetector, used in intermediate nuclear physics experiments, able to perform mass identification of the reaction products. To this purpose, it employs time of flight measurements done with traditional time to digital converters. In order to improve the resolution in mass identification, we have applied digital signal processing to time of flight measurements. This paper presents the methodology for data analysis, the adopted algorithms and the results obtained at different sampling frequencies (mass identification up to A = 33 for the reaction products produced by a 20.5 MeV/u 20Ne beam on 27Al target).

The digital pulse shape data acquisition (DAQ) system used by the large area telescopes of the 4pi-multidetector CHIMERA requires transferring large amount of data to the computer. This is necessary so that the same information can be extracted from the detector pulses as in previous analog based systems. To overcome this problem, we have used a sampling ADC-board equipped with two TigerSHARC digital signal processors. The board receives the data and reconstructs the event parameters online. The data volume is significantly reduced by transmitting to the DAQ only the reconstructed event parameters

The use of NE102A-BaF2 phoswich detector drastically improves the particle identification with respect to BaF2 crystals. To better exploit the possibility of light ion discrimination we plan to apply digital signal processing to the signals on-beam collected with NE102A-BaF2 phoswich. In this contribution we present the preliminary results obtained for the natural background of BaF2 and for the heavy ion charge identification (up to Z = 50) and light particle mass identification using digital pulse shape acquisition and a 12-bit, 2 Gsample/s sampling analog to digital converter.

The capability of digital pulse shape technique to acquire data from CHIMERA detection cells (Si-CsI(Tl) telescopes) has been evidenced in our previous works. We have now applied this technique to the charge discrimination of the products stopped in the silicon detectors. Large area totally depleted CHIMERA planar silicon detectors (5 cmtimes5 cm area, 300 mum thick) in both rear and front side injection have been used. In preliminary tests full charge identification for the reaction products up to Z=11 have been obtained for products both crossing (DeltaE-E technique) and stopping in the silicon detector, using a 21 MeV/u 20Ne beam at the LNS Superconducting Cyclotron in Catania. The quality of the obtained results clearly indicates that the digital signal processing approach is able to give excellent results in this application, too

We have designed, built, and tested an on-line pre-analysis and data-storage unit for the data acquisition system of the 4/spl pi/-detector CHIMERA. The unit uses special algorithms to perform particle identification and automatic peak detection. It tags in charge each event and stores the results on external unit, together with the raw data. It consists of two commercial 2 GHz workstations connected together through 1 Gb/s Ethernet boards and to the data acquisition system through a 100 Mb/s Ethernet.

Mass and atomic-number identification (ID) of reaction products is a fundamental requirement of any nuclear reaction study. An effective particle-ID method is demonstrated, based on pulse shape analysis/discrimination (PSD) applied to large-area, single-element silicon detectors. This technique uses commercial electronic modules and achieves atomic number resolution rivaling that typically obtained with multi-element (/spl Delta/E-E) detector telescopes. The method is applied to the CHIMERA detector system without compromising its time-of-flight (TOF) resolution. In-beam tests of the PSD method have been performed with large-area, 300-/spl mu/m thick CHIMERA silicon detectors, measuring particles from the /sup 19/F+/sup 12/C reaction at Tandem energies. Performance of a simple PSD set up is discussed, for front and rear particle injection.

In previous papers we have shown the applicability of digital pulse shape acquisition to the large area telescopes of the 4/spl pi/-multidetector CHIMERA. In view of measuring with this technique the time of flight of the reaction products to obtain also mass identification, we have performed several tests in laboratory, using pulse and waveform generators, and preliminary measurements with a Ne beam at 20.5 MeV/u, at different sampling frequencies. In this contribution we present the preliminary results obtained.

A 100 MS/s 14-bit Sampling Analog-to-Digital converter has been used to perform digital pulse-shape acquisition. The signals from a typical CHIMERA detector cell are collected both using a standard CHIMERA electronic chain, up to the amplifier, and directly from the preamplifier. The preliminary on-beam results are presented.

The on-line computation of special algorithms, as power-law for particle identification in nuclear physics, is a basic problem requiring real-time computational resources that have to fit time constraints, due to the randomness of nuclear events, and assure correctness. Present work concentrates on the possibility to use a low cost commercially available DSP boards for this purpose. The used DSP board computes in real-time transcendental functions expanded in Chebychev polynomial series with assembler routines ad hoc written, in order to perform the identification of the charged particles emitted in nuclear reactions. In particular a presentation of an emulation framework is described where Assembler DSP algorithms are tested at full speed, while input and output are tested at low velocity, by using two host PC, simulating peripherals for the I/O data.

The paper deals with the evaluation of the real-time behavior of a proposed kind of computing system for monitoring and controlling multidetector arrays used in nuclear physics experiments. The system was implemented by extending a previous monoprocessor system in a multiprocessing environment, based on ADSP-21060-SHARC digital signal processors. The proposed system is being developed within the CHIMERA multidetector project.

A commercial DSP-based board installed in a host-PC was employed for the fast, on-line and real-time computation of special algorithms, in order to perform event selection and operate as a 2nd level trigger. Moreover an ad hoc built interface, realized using PLDs with a view to connecting the DSP-board to the ADCs and to the data acquisition system, has been tested in order to evaluate the performances of these programmable devices used as a look-up-table and as a decisional part of a 1st level trigger.

Prototypes of new passivated implanted planar silicon detectors, obtained for the first time from 6 in. silicon slices, have been tested. The time and energy resolutions have been studied as a function of the type and energy of the detected particles, in order to test the performances of these detectors for time of flight measurements in the Chimera project. Some problems arising from edge effects observed in double-pad detectors have been solved by using a guard ring.

The light response of large CsI(TI) crystals supplied by various companies and coupled to photodiodes has been investigated. Energy resolution measurements and Z = 1 isotopic identification using the two gates method have been performed with in-beam experiments.

We have designed, built and tested an on-line pre-analysis and data-storage unit for the CHIMERA data acquisition system. The unit uses special algorithms to allow for particle identification and automatic peak detection. It tags in charge each event and stores the results on tape, together with the raw-data without any additional dead-time. The computational unit consists of two commercial 2 GHz PCs connected together through 1 Gb/s Ethernet boards and to the 100 Mb/s Ethernet of the data acquisition system.

In any of the modern 4/spl pi/ particle detector array improvements of the measured parameters have been envisaged. Pulse shape discrimination (PSD) is an efficient electronic tool which can be applied to a single detector to achieve atomic number Z separation of the particles comparable to the /spl Delta/E - E telescopes. In the present study, a simple PSD device based on commercially available modules has been discussed with the motivation of future improvement in CHIMERA detector system without sacrificing time resolution in time of flight (TOF) measurement. In beam studies of PSD have been carried out following the ejected particles from /sup 19/F + /sup 12/C reaction at tandem energies with 2 large area - 300 /spl mu/m - silicon detectors of CHIMERA multi-detector. Front-side and rear-side entry of the detected ions were explored. Performance of the PSD set up has been discussed.

The capability of digital pulse shape technique to acquire data from CHIMERA detection cells (Si-CsI(Tl) telescopes) has been evidenced in our previous works. /spl Delta/E-E scatter plots to obtain charge identification for the detected reaction products and fast-slow scatter plots from the CsI(Tl) light pulses for light charged product identification have been carefully reconstructed. We have now applied this technique to the charge discrimination of the products which stop in the silicon detectors, by using large area totally depleted CHIMERA silicon detectors (300 /spl mu/m thick, 5/spl times/5 cm/sup 2/ area) in reverse mount. In preliminary tests full charge identification for the reaction products up to Z=11 have been obtained for products both crossing the silicon detector (/spl Delta/E-E technique) and stopping in it, using a 21.1 MeV/u /sup 20/Ne beam at the LNS superconducting cyclotron in Catania. The quality of the obtained results clearly indicates that the digital signal processing approach is able to give excellent results in this application, too.

In nuclear physics at intermediate energies the use of multidetector arrays consisting of thousands of detectors is customary. For each event up to one hundred of detection cells are hit. As usual in the case of a large number of detectors tools are needed for their stability control and the data analysis automation. This paper presents a simple, novel approach to the classification of data collected using a multidetector array. We describe the results obtained by applying special algorithms to the signals coming from the detection cells of the 4/spl pi/ multidetector array CHIMERA, constituted by telescopes of a thin silicon transparent detector coupled to a thick CsI(Tl) scintillator. The method, which does not require any preliminary energy calibration, consists in a quasiautomatic data processing and produces frequency distributions of the most significant physical parameters. These monodimensional spectra are more easily automatically analyzed than the standard bidimensional scatter plots. In particular, in the proposed system the interactive phase is shorter than in the usual analysis, thus saving time and operator intervention. The proposed method has been successfully used both in the off-line data analysis and in the control of the multidetector stability.

Although the seismic behaviour of shallow circular tunnels in soft ground is generally safer than aboveground structures, some tunnels were recently damaged during earthquakes. In some cases, damage was associated with strong ground shaking and site amplification, which increased the stress level in the tunnel lining. Pseudo-static and simplified dynamic analyses enable to assess transient changes in internal forces during shaking. Nevertheless, experimental evidences of permanent changes in internal loads in the tunnel lining would suggest that a full dynamic analysis including plastic soil behaviour should be performed when modelling the dynamic interaction between the tunnel and the ground. While sophisticated numerical methods can be used to predict seismic internal forces on tunnel structures during earthquakes, the accuracy of their predictions should be validated against field measurements, but the latter are seldom available. A series of centrifuge tests were therefore carried out at the University of Cambridge (UK) on tunnel models in sand, in the framework of a research project funded by the Italian Civil Protection Department. A numerical Round Robin on Tunnel Tests was later promoted among some research groups to predict the observed behaviour by means of numerical modelling. In this paper, the main results of five selected numerical predictions are summarized and compared with the experimental results. �� 2014 Springer-Verlag Berlin Heidelberg.

The seismic design issues for shallow tunnel design are often poor or absent in the current national or international recommendations. Moreover, the available simplified formulations for the evaluation of tunnel internal forces, induced by seismic actions, account only for transient effects due to wave passage. Some centrifuge tests on circular tunnels in dry sand, recently performed, showed that permanent increments of internal forces clearly arise in the tunnel lining after seismic events. This evidence is also confirmed in real scale monitoring of tunnels,which suffered residual stresses after strong earthquakes. In order to capture the permanent increments of internal forces on a tunnel lining due to dynamic loadings, a series of numerical analyses have been performed by using a material model which includes hardening plasticity and the strain dependency of stiffness and damping.A experimental set of centrifuge tests in sand was used to validate the numerical analyses. The influence of the soil-lining relative stiffness and of the shear stress transmission at the interface between the soil and the lining are discussed in the paper.