Research and development of a gamma-ray imaging spectrometer in the MeV range in Barcelona

Copyright 2010 Society of Photo-Optical Instrumentation Engineers (SPIE). One print or electronic copy may be made for personal use only. Systematic electronic or print reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited.Gamma-ray astrophysics in the MeV energy range plays an important role for the understanding of cosmic explosions and acceleration mechanisms in a variety of galactic and extragalactic sources, e.g., Supernovae, Classical Novae, Supernova Remnants (SNRs), Gamma-Ray Bursts (GRBs), Pulsars, Active Galactic Nuclei (AGN). Through the development of focusing telescopes in the MeV energy range, it will be possible to reach unprecedented sensitivities, compared with those of the currently operating gamma ray telescopes. In order to achieve the needed performance, a detector with mm spatial resolution and very high peak efficiency is required. It will be also desirable that the detector could detect polarization of the source. Our research and development activities in Barcelona aim to study a gamma-ray imaging spectrometer in the MeV range suited for the focal plane of a gamma-ray telescope mission, based on CdTe pixel detectors arranged in multiple layers with increasing thicknesses, to enhance gamma-ray absorption in the Compton regime. We have developed an initial prototype based on several CdTe module detectors, with 11x11 pixels, a pixel pitch of 1mm and a thickness of 2mm. Each pixel is stud-bump bonded to a fanout board and routed to a readout ASIC to measure pixel position, pulse height and rise time information for each incident gamma-ray photon. We will report on the results of an optimization study based on simulations, to select the optimal thickness of each CdTe detector within the module to get the best energy resolution of the spectrometer.Peer reviewe

3D Printed Porous Polyamide Macrocapsule Combined with Alginate Microcapsules for Safer Cell-Based Therapies

Cell microencapsulation is an attractive strategy for cell-based therapies that allows the implantation of genetically engineered cells and the continuous delivery of de novo produced therapeutic products. However, the establishment of a way to retrieve the implanted encapsulated cells in case the treatment needs to be halted or when cells need to be renewed is still a big challenge. The combination of micro and macroencapsulation approaches could provide the requirements to achieve a proper immunoisolation, while maintaining the cells localized into the body. We present the development and characterization of a porous implantable macrocapsule device for the loading of microencapsulated cells. The device was fabricated in polyamide by selective laser sintering (SLS), with controlled porosity defined by the design and the sintering conditions. Two types of microencapsulated cells were tested in order to evaluate the suitability of this device; erythropoietin (EPO) producing C2C12 myoblasts and Vascular Endothelial Growth Factor (VEGF) producing BHK fibroblasts. Results showed that, even if the metabolic activity of these cells decreased over time, the levels of therapeutic protein that were produced and, importantly, released to the media were stable.This work was done under the BIOPAN project (CIBER-BBN). Authors wish to thank the intellectual and technical assistance from the ICTS "NANBIOSIS", more specifically by the Drug Formulation Unit (U10) and the Micro-Nano Technology Unit (U8) of the CIBER in Bioengineering, Biomaterials & Nanomedicine (CIBERBBN). Also, they thank the support to research on cell microencapsulation from the University of the Basque Country UPV/EHU (EHUA 16/06) and the Basque Country Government (Grupos Consolidados, No ref: IT907-16). The authors acknowledge the financial support from the Ministerio de Economia y Competitividad (MINECO) (Spain) through Ramon y Cajal program (RYC-2013-14479). This work has made use of the Spanish ICTS Network MICRONANOFABS partially supported by MINECO

Smart biosensing device for tracking fish behaviour

Biosensor technology for tracking individual challenged fish behaviour has the potential to revolutionize aquaculture, allowing farmers and breeders to orientate selective breeding towards more robust and efficient fish or improve culture conditions for a more sustainable and ethical production. The proposed solution within the AQUAEXCEL2020 EU project is a stand-alone, small and light (1 g) device (AEFishBIT), based on a tri-axial accelerometer and a microprocessor. It is externally attached to the operculum to monitor physical activity by mapping accelerations in x- and y-axes, while operculum beats (z-axis) serve as a measurement of respiratory frequency. The conducted operculum attachment protocol does not show signs of tissue damage or growth impairment in active feeding gilthead sea bream. AEFishBIT offers a wide range of new information based on individual behaviour, allowing to point out the asynchrony of movements as an indirect measure of aging and adaptability to farming environment, as well as to discriminate different coping behaviour (proactive or reactive) of gilthead sea bream challenged with low water oxygen concentrations. AEFishBIT also provides reliable information of disease outcome in fish parasitized with an intestinal myxozoan, emerging as a powerful tool for sensing the quality of the environment and improving selective breeding protocols.The study has received funding from the European Union’s Horizon 2020 research and innovation programme, GA no 652831 (AQUAEXCEL2020)

Ultra-Low Power Sensor Devices for Monitoring Physical Activity and Respiratory Frequency in Farmed Fish

Integration of technological solutions aims to improve accuracy, precision and repeatability in farming operations, and biosensor devices are increasingly used for understanding basic biology during livestock production. The aim of this study was to design and validate a miniaturized tri-axial accelerometer for non-invasive monitoring of farmed fish with re-programmable schedule protocols. The current device (AE-FishBIT v.1s) is a small (14 mm × 7 mm × 7 mm), stand-alone system with a total mass of 600 mg, which allows monitoring animals from 30 to 35 g onwards. The device was attached to the operculum of gilthead sea bream (Sparus aurata) and European sea bass (Dicentrarchus labrax) juveniles for monitoring their physical activity by measurements of movement accelerations in x- and y-axes, while records of operculum beats (z-axis) served as a measurement of respiratory frequency. Data post-processing of exercised fish in swimming test chambers revealed an exponential increase of fish accelerations with the increase of fish speed from 1 body-length to 4 body-lengths per second, while a close relationship between oxygen consumption (MO2) and opercular frequency was consistently found. Preliminary tests in free-swimming fish kept in rearing tanks also showed that device data recording was able to detect changes in daily fish activity. The usefulness of low computational load for data pre-processing with on-board algorithms was verified from low to submaximal exercise, increasing this procedure the autonomy of the system up to 6 h of data recording with different programmable schedules. Visual observations regarding tissue damage, feeding behavior and circulating levels of stress markers (cortisol, glucose, and lactate) did not reveal at short term a negative impact of device tagging. Reduced plasma levels of triglycerides revealed a transient inhibition of feed intake in small fish (sea bream 50–90 g, sea bass 100–200 g), but this disturbance was not detected in larger fish. All this considered together is the proof of concept that miniaturized devices are suitable for non-invasive and reliable metabolic phenotyping of farmed fish to improve their overall performance and welfare. Further work is underway for improving the attachment procedure and the full device packaging

Laser stripe peak detector for 3D scanners. A FIR filter approach

The accuracy of a 3D reconstruction using laser scanners is significantly determined by the detection of the laser stripe. Since the energy pattern of such a stripe corresponds to a Gaussian profile, it makes sense to detect the point of maximum light intensity (or peak) by computing the zero-crossing point of the first derivative of such Gaussian profile. However, because noise is present in every physical process, such as electronic image formation, it is not sensitive to perform the derivative of the image of the stripe in almost any situation, unless a previous filtering stage is done. Considering that stripe scanning is an inherently row-parallel process, every row of a given image must be processed independently in order to compute its corresponding peak position in the row. This paper reports on the use of digital filtering techniques in order to cope with the scanning of different surfaces with different optical properties and different noise levels, leading to the proposal of a more accurate numerical peak detector, even at very low signal-to-noise ratios

Laser stripe peak detector for 3D scanners: a FIR filter approach

The accuracy of a 3D reconstruction using laser scanners is significantly determined by the detection of the laser stripe. Since the energy pattern of such a stripe corresponds to a Gaussian profile, it makes sense to detect the point of maximum light intensity (or peak) by computing the zero-crossing point of the first derivative of such Gaussian profile. However, because noise is present in every physical process, such as electronic image formation, it is not sensitive to perform the derivative of the image of the stripe in almost any situation, unless a previous filtering stage is done. Considering that stripe scanning is an inherently row-parallel process, every row of a given image must be processed independently in order to compute its corresponding peak position in the row. This paper reports on the use of digital filtering techniques in order to cope with the scanning of different surfaces with different optical properties and different noise levels, leading to the proposal of a more accurate numerical peak detector, even at very low signal-to-noise ratio

Measurement of mobility and lifetime of electrons and holes in a Schottky CdTe diode

We report on the measurement of drift properties of electrons and holes in a CdTe diode grown by the travelling heating method (THM). Mobility and lifetime of both charge carriers has been measured independently at room temperature and fixed bias voltage using charge integration readout electronics. Both electrode sides of the detector have been exposed to a 241 Am source in order to obtain events with full contributions of either electrons or holes. The drift time has been measured to obtain the mobility for each charge carrier. The Hecht equation has been employed to evaluate the lifetime. The measured values for μτ (mobility-lifetime product) are in agreement with earlier published data

Thin film bulk acoustic wave resonator and method for performing heterogeneous integration of the same with complementary -metal-oxide- semiconductor integrated circuit

Fecha de solicitud: 28-08-2008.- Titular: Consejo Superior de Investigaciones Científicas (CSIC)The invention relates to a method of performing heterogeneous integration of thin-film bulk acoustic wave resonator, FBAR, with complementary-metal-oxide-semiconductor integrated-circuit, CMOS, technologies. According to the invention, the method comprising the following steps, namely: i) forming a first device wafer including said FBAR, a sacrificial layer and substrate, with said FBAR devices defined on a first face; ii) forming a second device wafer including circuit elements fabricated on a CMOS technology, with CMOS integrated-circuits defined on a first face; iii) wafer-level-transferring and integration of the first device wafer including FBAR, a sacrificial layer and substrate, into the second device wafer including circuit elements fabricated on a CMOS substrate; iv) wafer-level-releasing of FBAR devices from their supporting substrate to provide mechanical isolation of FBAR devices. The invention further comprises a heterogeneous-technology semiconductor assembly, radio-frequency system and a sensing system.Peer reviewe