Perspectives on Reoffenders: The Views of Detainees, the General Public and Those Working with Offenders

The literature has offered significant data on reoffending: for example, the relationship with drug taking, addiction, mental illness and security. However, research directly involving the voices of detainees and those intervening in the prevention of reoffending appears to be less developed. The present research aims to observe how reoffending is approached by the various players involved: the detainees (whether reoffenders or not), educators and ordinary people. In particular we endeavour to determine how reoffending is perceived, interpreted and managed. The ultimate aim is to assist those involved in the improvement of social reintegration. Interviews revealed substantial differences in how reoffending is interpreted and perceived, and this influences both the management of the risk of reoffending and the process of rehabilitation into society. Furthermore, the results showed some improvements, such as in the teamwork by all players involved, in education for the detainees, and in the implementation of social reintegration projects as alternatives to imprisonment

X and Y waves in the spatiotemporal Kerr dynamics of a self-guided light beam

The nonlinear stage of development of the spatiotemporal instability of the monochromatic Townes beam in a medium with self-focusing nonlinearity and normal dispersion is studied by analytical and numerical means. Small perturbations to the self-guided light beam are found to grow into two giant, splitting Y pulses featuring shock fronts on opposite sides. Each shocking pulse amplifies a co-propagating X wave, or dispersion- and diffraction-free linear wave mode of the medium, with super-broad spectrum.Comment: 9 pages, 9 figure

On the nature of spatiotemporal light bullets in bulk Kerr media

We present a detailed experimental investigation, which uncovers the nature of light bullets generated from self-focusing in a bulk dielectric medium with Kerr nonlinearity in the anomalous group velocity dispersion regime. By high dynamic range measurements of three-dimensional intensity profiles, we demonstrate that the light bullets consist of a sharply localized high-intensity core, which carries the self-compressed pulse and contains approximately 25% of the total energy, and a ring-shaped spatiotemporal periphery. Sub-diffractive propagation along with dispersive broadening of the light bullets in free space after they exit the nonlinear medium indicate a strong space-time coupling within the bullet. This finding is confirmed by measurements of spatiotemporal energy density flux that exhibits the same features as stationary, polychromatic Bessel beam, thus highlighting the physical nature of the light bullets

A new modulation technique for high data rate low power UWB wireless optical communication in implantable biotelemetry systems

We report on the development of a novel modulation technique for UWB wireless optical communication systems for application in a transcutaneous biotelemetry. The solution, based on the generation of short laser pulses, allows for a high data rate link whilst achieving a significant power reduction (energy per bit) compared to the state-of-the-art. These features make this particularly suitable for emerging biomedical applications such as implantable neural/biosensor systems. The relatively simple architecture consists of a transmitter and receiver that can be integrated in a standard CMOS technology in a compact Silicon footprint. These parts include circuits for bias and drive current generation, conditioning and processing, optimised for low-volt age/low-power operation. Preliminary experimental findings validate the new paradigm and show good agreement with expected results. The complete system achieves a BER less than 10-7, with maximum data rate of 125Mbps and estimated total power consumption of less than 3mW

Design of Wireless Sensor Nodes for Structural Health Monitoring applications

Enabling low-cost distributed monitoring, wireless sensor networks represents an interesting solution for the implementation of structural health monitoring systems. This work deals with the design of wireless sensor networks for health monitoring of civil structures, specifically focusing on node design in relation to the requirements of different structural monitoring application classes. Design problems are analysed with specific reference to a large-scale experimental setup (the long-term structural monitoring of the Basilica S. Maria di Collemaggio, L’Aquila, Italy). Main limitations emerged are highlighted, and adopted solution strategies are outlined, both in the case of commercial sensing platform and of full custom solutions

An 80 Mbit/s radiation-tolerant optical receiver for the CMS digital optical link

The CMS tracker slow control system will use approximately 1000 digital optical links for the transmission of timing, trigger and control signals. In this system, the 80 Mbit/s optical receiver at the detector end of each optical link has to be radiation hard since it will operate in the severe radiation environment of the CMS tracker (10 Mrad in 10 years). We have developed a prototype circuit in a 0.25 mu m commercial CMOS process using radiation tolerant layout practices to achieve the required radiation tolerance. This effective technique consists in the systematic use of enclosed (edgeless) NMOS transistors and guardrings, and relies in the natural total dose hardness of the thin gate oxide of deep submicron processes. The circuit features an automatic gain control loop allowing detection of wide dynamic range input signals (-20 to -3 d Bm) with minimum noise, compatible with the maximum expected radiation-induced drop in quantum efficiency of the PIN photodiode. A second feedback loop compensates a photodiode leakage current up to 100 mu A, and the circuit outputs an LVDS signal. Four receiver channels were integrated in a 2*2 mm/sup 2/ chip, out of which two were simultaneously bonded to two PIN photodiodes, and their BER performance was measured before and after an irradiation with 10 keV X-rays up to 20 Mrad (SiO/sub 2/). (11 refs)

Analogue Gravity and ultrashort laser pulse filamentation

Ultrashort laser pulse filaments in dispersive nonlinear Kerr media induce a moving refractive index perturbation which modifies the space-time geometry as seen by co-propagating light rays. We study the analogue geometry induced by the filament and show that one of the most evident features of filamentation, namely conical emission, may be precisely reconstructed from the geodesics. We highlight the existence of favorable conditions for the study of analogue black hole kinematics and Hawking type radiation.Comment: 4 pages, revised versio

Discursive chains: How prison becomes real and chains identity movements for a sex offender

Detainees enact a "self" that is faced with the prejudices and stereotypes of the crime for which that detainee was convicted. Of all inmates, sex offenders face the greatest risk of receiving social condemnation alongside their prison sentence. This empirical study worked with 32 male sex offenders over 18 years old that were housed in the "protected" unit of the Due Palazzi. The following analysis explores how these men are required to manage their "self," hetero-narrations, perception of everyday interactions in the protected unit, and conceptions about the rehabilitation path. Moreover, the detainees' view on the prison's strategic opportunities for promoting effective change in their condition and identity are also examined. Discourse analysis applied to an open answer questionnaire showed that, rather than facing the stigma assigned to them, the detainees tend to minimize the importance of storytelling and construct alternative biographies to share with other inmates. Managing narratives allows the sex offenders to distance themselves from the perceived threats of living with other detainees; however, it also prevents the re-signification of their offenses. As such, the rules of "secrecy" must be considered by both qualitative researchers who conduct studies in prisons and prison administrators who plan the housing and treatment of sex offenders