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The transient current technique (TCT) is widely used in the field of silicon particle detector development. So far, only laser wavelengths with a photon energy larger than or similar to the silicon bandgap (single photon absorption) were used. Recently, measurements using two-photon absorption (TPA) for silicon detector testing have been carried out for the first time. Excess carriers are only created at the focal point of the laser beam and thus resolution in all three spatial directions could be achieved. The resolution perpendicular to the incident laser beam could be increased roughly by a factor of 10. First measurements using this new method were performed at the Singular Laser Facility of Universidad del País Vasco (UPV)/Euskal Herriko Unibertzitatea (EHU). Following the initial success of the method, a compact TPA-TCT setup is under development. A first description of the setup and laser system is presented in this article., This work was supported in part by the Spanish Ministry of Economy and Competitiveness (MINECO) under Grant FPA2013-48387-C6-1-P and in part by the Wolfgang Gentner Programme of the German Federal Ministry of Education and Research under Grant 05E15CHA.

International audience; The RD53A large scale pixel demonstrator chip has been developed in 65 nm CMOS technology by the RD53 collaboration, in order to face the unprecedented design requirements of the pixel 2 phase upgrades of the CMS and ATLAS experiments at CERN. This prototype chip is designed to demonstrate that a set of challenging specifications can be met, such as: high granularity (small pixels of 50×50 or 25× 100 µm2) and large pixel chip size (~2x2 cm2), high hit rate (3 GHz/cm2), high readout speed, very high radiation levels (500 Mrad - 1 Grad) and operation with serial powering. Furthermore, coping with the long latency of the trigger signal (~12.5 µs), used to select only events of interest in order to achieve sustainable output data rates, requires increased buffering resources in the limited pixel area. The RD53A chip has been fabricated in an engineer run. It integrates a matrix of 400×192 pixels and features various design variations in the analog and digital pixel matrix for testing purposes. This paper presents an overview of the chip architecture and of the methodologies used for efficient design of large complex mixed signal chips for harsh radiation environments. Experimental results obtained from the characterization of the RD53A chip are reported to demonstrate that design objectives have been achieved. Moreover, design improvements and new features being developed in the RD53B framework for final ATLAS and CMS production chips are discussed

The COTS power transistors based in GaN were exposed to TID effects by 10-keV X-rays. These HEMTs were tested in the On- and Off-state bias conditions. Switching tests were performed before and after irradiation steps. The devices were characterized at temperatures ranging from −50 °C to +75 °C. The results indicate that the GaN-technology is a great candidate to be used in harsh environments, because the tested devices have presented an expressive recovery of its parameters of Vth, gmmax and switching times, after accumulation of 350 krad of TID.

Introduction Children with atopic dermatitis (AD) experience significant sleep disruption due to nocturnal scratching. Our group has found distinct patterns of limb movements in contrast to control and PLMD patients. To expand on previous findings, our objective was to characterize timing and duration of scratch v. non-scratch movement in children with AD coincidentally undergoing polysomnography (PSG). Methods Retrospective chart review of PSG, video footage was synchronized with the EEG and limb electrode readings using a time/date generator and was then operationally classified as either scratching or non-scratching movement. Analysis of data was done using SPSS and groups were compared using an ANOVA. Results We analyzed four previously completed sleep studies in children with atopic dermatitis (1 female and 3 males), mean age years±SD 11.3±1.0, mean BMI±SD 21.9±7.1, mean AHI±SD 2.3±0.8. Average scratch duration was not significantly different by sleep stage, N1v.N2v.N3v.REM (mean scratch duration in seconds±SD= 9.0±1.5 v 6.3±3.2 v. 11.9±11.8 v. 6.3±7.3, respectively p=0.65). However, frequency of scratching events were more common during N2v.N1v.N3v.REM (mean scratching events±SD= 9.3±3.9 v 3.8±1.7 v. 4.3±4.3 v. 1.3±1.9, respectively p=0.02). Yet, given the duration of total time spent in sleep stages, minutes of scratching events occupied the largest percentage of N1v.N2v.N3v.REM (mean% ±SD= 3.9±0.9 v. 0.6±0.4 v. 0.4±0.2 v. 0.3±0.5, respectively, p&lt0.01). Interestingly, non-scratch related movements were not significantly different between sleep stages (p=0.2). However, non-scratch related movements trended to occupy the largest percentage of N1v.N2v.N3v.REM (mean% ±SD= 9.3±7.7 v. 2.1±1.6 v. 1.5±0.8 v. 1.9±1.4, respectively, p=0.05). Conclusion Our results suggest that scratching episodes in children with AD occur most commonly during N2 sleep, but occupy the largest % of N1 sleep. Future work will include comparing these limb movements to age and gender-matched allergic rhinitis patients. Support This study was unfunded.

The purpose of this work is to evaluate the absorbed dose to the eye lenses due to the cone beam computed tomography (CBCT) system used to accurately position the patient during head-and-neck image guided procedures. The on-board imaging (OBI) systems (v.1.5) of Clinac iX and TrueBeam (Varian) accelerators were used to evaluate the imparted dose to the eye lenses and some additional points of the head. All CBCT scans were acquired with the Standard-Dose Head protocol from Varian. Doses were measured using thermoluminescence dosimeters (TLDs) placed in an anthropomorphic phantom. TLDs were calibrated at the beam quality used to reduce their energy dependence. Average dose to the lens due to the OBI systems of the Clinac iX and the TrueBeam were 0.71 ± 0.07 mGy/CBCT and 0.70 ± 0.08 mGy/CBCT, respectively. The extra absorbed dose received by the eye lenses due to one CBCT acquisition with the studied protocol is far below the 500 mGy threshold established by ICRP for cataract formation (ICRP 2011 Statement on Tissue Reactions). However, the incremental effect of several CBCT acquisitions during the whole treatment should be taken into account.

This paper presents Analog Fault Tolerant University of Seville Debugging System (AFTU), a tool to evaluate the Single-Event Effect (SEE) sensitivity of analog/mixed signal microelectronic circuits at transistor level. As analog cells can behave in an unpredictable way when critical areas interact with the particle hitting, there is a need for designers to have a software tool that allows an automatic and exhaustive analysis of Single-Event Effects influence. AFTU takes the test-bench SPECTRE design, emulates radiation conditions and automatically evaluates vulnerabilities using user-defined heuristics. To illustrate the utility of the tool, the SEE sensitivity of a 13-bits Successive Approximation Analog-to-Digital Converter (ADC) has been analysed. This circuit was selected not only because it was designed for space applications, but also due to the fact that a manual SEE sensitivity analysis would be too time-consuming. After a user-defined test campaign, it was detected that some voltage transients were propagated to a node where a parasitic diode was activated, affecting the offset cancelation, and therefore the whole resolution of the ADC. A simple modification of the scheme solved the problem, as it was verified with another automatic SEE sensitivity analysis.

Introduction and purpose Dosimetry Check (DC) (Math Resolutions) is a commercial EPID-based dosimetry software, which allows performing pre-treatment and transit dosimetry. DC provides an independent verification of the treatment, being potentially of great interest due to the high benefits of the in vivo volumetric dosimetry, which guarantee the treatment delivery and anatomy constancy. The aim of this work is to study the differences in dose between DC and the Treatment Planning System (TPS) to establish an accuracy level of the system. Material and methods DC v.3.8 was used along with Varian Clinac iX accelerator equipped with EPID aS1000 and Eclipse v.10.0 with AAA and Acuros XB calculation algorithms. The DC evaluated version is based on a pencil beam calculation algorithm. Various plans were generated over several homogeneous and heterogeneous phantoms. Isocentre point doses and gamma analysis were evaluated. Results Total dose differences at the isocentre between DC and TPS for the studied plans are less than 2%, but single field contributions achieve greater values. In the presence of heterogeneities, the discrepancies can reach up to 15%. In transit mode, DC does not consider properly the couch attenuation, especially when there is an air gap between phantom and couch. Conclusions The possibility of this in vivo evaluation and the potentiality of this new system have a very positive impact on improving patient QA. But improvements are required in both calculation algorithm and integration with the record and verify system.

International audience; RD53A is a large scale 65 nm CMOS pixel demonstrator chip that has been developed by the RD53 collaboration for very high rate (3 GHz/cm$^2$) and very high radiation levels (500 Mrad, possibly 1 Grad) for ATLAS and CMS phase 2 upgrades. It features serial powering operation and design variations in the analog and digital pixel matrix for different testing purposes. The design and verification of RD53A are described together with an outline of the plans to develop final pixel chips for the two experiments.

Flight missions were made in Brazilian territory in 2009 and 2011 with the aim of measuring the cosmic radiation dose rate incident on aircraft in the South Atlantic Magnetic Anomaly and to compare it with Monte Carlo simulations. During one of these flights, small fluctuations were observed in the vicinity of the aircraft with formation of Cumulonimbus clouds. Motivated by these observations, in this work, the authors investigated the relationship between the presence of clouds and the neutron flux and dose rate incident on aircraft using computational simulation. The Monte Carlo simulations were made using the MCNPX and Geant4 codes, considering the incident proton flux at the top of the atmosphere and its propagation and neutron production through several vertically arranged slabs, which were modelled according to the ISO specifications.

Displacement damage effect on MOS capacitors is analyzed in this work with the aid of TCAD simulations. A noticeable capacitance reduction in the accumulation mode is observed in the High Frequency C–V characteristic curve after a 24 GeV proton irradiation. This effect is clearly distinguishable from ionizing damage effects, otherwise negligible under the specific conditions of the experiment. The capacitance reduction is identified with the increase of the substrate resistivity, due to the modification of its effective doping concentration. Supported on a well-established traps model, the expected displacement damage defects are simulated as a function of the fluence, allowing the identification of donor trap levels as the responsible of the phenomenon for p-type substrate MOS capacitors.

Bu çalışma, 22-26 Şubat 2016 tarihleri arasında Ghent[Belçika]’da düzenlenen 13. Workshop on Resistive Plate Chambers and Related Detectors’da bildiri olarak sunulmuştur. We give a short compendium of the main ongoing detectors and concepts capable of performing accurate sub-100 ps timing at high particle fluxes and on large areas, through technologies based on gaseous media. We briefly discuss the state-of-the-art, technological limitations and prospects, and a new bizarre idea. RD51 collaboration

International audience; This paper is a review of recent progress of RD53 Collaboration. Results obtained onthe study of the radiation effects on 65 nm CMOS have matured enough to define first strategies toadopt in the design of analog and digital circuits. Critical building blocks and analog very frontend chains have been designed, tested before and after 5–800 Mrad. Small prototypes of 64 64pixels with complex digital architectures have been produced, and point to address the main issuesof dealing with extremely high pixel rates, while operating at very small in-time thresholds in theanalog front end. The collaboration is now proceeding at full speed towards the design of a largescale prototype, called RD53A, in 65 nm CMOS technology

The first Inverse Low Gain Avalanche Detector (iLGAD) have been fabricated at IMB-CNM (CSIC). The iLGAD structure includes the multiplication diffusions at the ohmic contact side while the segmentation is implemented at the front side with multiple P + diffusions. Therefore, iLGAD is P on P position-sensitive detector with a uniform electric field all along the device area that guarantees the same signal amplification wherever a particle passes through the sensitive bulk solving the main draw of the LGAD microstrip detector. However, the detection current is dominated by holes flowing back from the multiplication junction with the subsequent transient current pulse duration increase in comparison with conventional LGAD counterparts. Applications of iLGAD range from tracking and timing applications like determination of primary interaction vertex to medical imaging. The paper addresses the optimization of the iLGAD structure with the aid of TCAD simulations, focusing on the electric field profiles of iLGAD and LGAD microstrip structures and the corresponding gain. The electrical performance of the first fabricated samples is also provided. For the first time, we have experimental demonstrate the signal amplification of this novel iLGAD detector

Due to the increasing interest on laterally diffused MOS (LDMOS) transistors as a part of power electronics in the high energy physics (HEP) experiments, the effect of total ionising dose (TID) on their electrical performances has been experimentally measured. The analysis of the experimental results requires the aid of physics-based simulations to study the impact of TID effects on the LDMOS drift oxide layer. In this work, a simulation methodology is developed in order to analyse the changes in the electric field distribution as a consequence of the TID induced trapped charge, and its relationship with the technological parameters and the bias conditions. The simulation results are compared with the experimental data.

There is an increasing interest in the aerospace industry to reduce the cost of the systems by means of using Commercial Off The Shelf (COTS) devices. The engineering of novel microsatellites and nanosatellites are clear examples of this new trend. However, the use of sub-micron technologies has led to greater sensitivity of these devices to radiation-induced transient faults, limiting the exploitation of this approach in critical systems. This paper presents an innovative application of soft-core microprocessor based embedded systems, to design dependable and reduced-cost critical systems with COTS reconfigurable devices (flash based FPGAs). To make this possible, it is necessary to fine-tune the protection strategy by combining selectively fault mitigation techniques based on hardware or software. In this way, the resultant system not only fulfills both the design constraints and the dependability requirements, but also avoids the cost provoked by excessive use of protection mechanisms. A case study is presented in which the design space exploration between hardware and software protection techniques permits to find the best trade-offs among performance, reliability, memory size and hardware cost in a dependable subsystem.

Pulsed laser testing is a useful technique for an accurate inspection of potential weak zones in a layout of an integrated circuit. A laser pulse can provoke a similar effect as a particle hitting with the advantage of a perfect location of the hitting point. The present work describes a general method to determine a Pulsed Laser Single Event Upset (SEU) Cross Section over digital circuits by means of counting statistics. The technique is based on a coincidence detector that counts fault events by comparing synchronous outputs of the digital circuit under test and a replica of the design running on a control FPGA. A correspondence map, previously generated by injection fault analysis techniques on the replica, establishes a one-way correspondence between output patterns and each bit flip. With this scheme, the SEU is detected dynamically just using a comparison between the running model and the circuit.

Use of advanced communication technologies, highly integrated control, and programming platforms drastically increases the performance of industrial control systems. That is the case of Motronic, where the synergistic collaboration between industry and academia has led to an advanced distributed network control system. To be commercially successful, it needs to have a low cost and to be robust, even if this requirement implies that it is a custom design and not based on previously existing commercial solutions. Use of standards and off-the-shelf products lower development costs, but usually raise production costs. In this paper, we show that, in certain applications, design of a new system from scratch is more advantageous. This system comprises a set of dynamically reconfigurable local controller nodes, a graphical programming environment, a remote supervision and control system, and a fault-tolerant fiber optical network. TCP/IP connectivity is provided by the use of a local gateway. Motronic is currently being applied in the integrated control of large production plants and in energy and power management industries.

Neutron-induced reaction cross sections are important for a wide variety of research fields ranging from the study of nuclear level densities, nucleosynthesis to applications of nuclear technology like design, and criticality and safety assessment of existing and future nuclear reactors, radiation dosimetry, medical applications, nuclear waste transmutation, accelerator-driven systems and fuel cycle investigations. Simulations and calculations of nuclear technology applications largely rely on evaluated nuclear data libraries. The evaluations in these libraries are based both on experimental data and theoretical models. CERN’s neutron time-of-flight facility n TOF has produced a considerable amount of experimental data since it has become fully operational with the start of its scientific measurement programme in 2001. While for a long period a single measurement station (EAR1) located at 185 m from the neutron production target was available, the construction of a second beam line at 20 m (EAR2) in 2014 has substantially increased the measurement capabilities of the facility. An outline of the experimental nuclear data activities at n TOF will be presented.

We introduce a new method based on the transient-current technique (TCT) for the radiation tolerance assessment of an n-in-p junction with a deep n-well on a relatively low-resistivity p-type substrate commonly used for HV-CMOS pixel sensors. The transient-current method here employed uses a femtosecond laser to generate excess carriers via a two-photon-absorption (TPA) process. Special attention has been paid to overcome the limitations of the conventional transient-current method based on single-photon-absorption carrier generation when applied to the HV-CMOS sensors. Specifically, we tackle the precise determination of the depletion region boundaries, including the deep-n-well spatial location, needed to calculate the effective doping concentration of the substrate. As illustration, we have applied this new TPA-based method to both a fresh and a neutron irradiated single-pixel deep-n-well diode manufactured in a 180 nm high-voltage CMOS process. In the irradiated device, concurrent with the expected effective acceptor removal in the p-type substrate, an indication of an effective donor removal in the DNW implant was also observed.

In this paper, a software simulation tool for automation of electrical sensitivity analysis of Single Event Effects (SEE) is presented. In particular, the proposed tool can be used to check the error sensitivity of analog designs with large number of transistors. The proposed methodology allows a rapid location of critical nodes in order to ensure a proper radiation-hardened performance under the influence of current injected Single Event Transient Effects (SET). As a case study, several operational amplifier architectures have been designed and simulated in a 130 nm CMOS technology, validating the performance of the implemented analysis method.

We report on the effect of the fiber coating on the radiation sensitivity of Fiber Bragg Gratings (FBG). For the first time this type of study has been carried out using a 13.5 MeV proton beam up to a fluence of 3.3 × 10 15 protons/cm 2 (total absorbed dose of 15 MGy). We observed a clear dependence of the radiation sensitivity on the coating, in particular, we have investigated the irradiation induced changes on the strain sensitivity; FBG strain coefficient remains stable for all the fiber within a 5%. This result demonstrates the suitability of FBGs as structural health and deformation monitors in the very hostile environment of the new generation of high-intensity particle physics proton colliders. © 2012 IEEE.

We report on the effect of the fiber coating on the radiation sensitivity of Fiber Bragg Gratings (FBG). For the first time this type of study has been carried out using a 13.5 MeV proton beam up to a fluence of 3.3 × 1015 protons/cm2 (total absorbed dose of 15 MGy). We observed a clear dependence of the radiation sensitivity on the coating, in particular, we have investigated the irradiation induced changes on the strain sensitivity; FBG strain coefficient remains stable for all the fiber within a 5%. This result demonstrates the suitability of FBGs as displacement transducers in the very hostile environment of the new generation of high-intensity particle physics proton colliders

This paper remarks the importance of defining real conditions for the radiation effects evaluation on embedded systems using a fault injection system. The influence of fault latency on the experiment results is illustrated by means of a case study.

Cadmium (Cd), tungsten (W), tellurium (Te), beryllium (Be), and lead (Pb), are non-essential metals pervasive in the human environment. Studies on athletes during training periods compared to non-training control subjects, indicate increased loss of minerals through sweat and urine. The aim of this study was to compare the level of these trace elements, determined by inductively coupled plasma mass spectrometry (ICP-MS) in urine samples, between athletes and age-matched sedentary subjects living in the same geographical area, although anthropometric and cardiovascular measurements showed that athletes have significantly (P ≤ 0.001) lower BMI, body fat and heart rate, whereas the muscle and bone percentage was significantly (P ≤ 0.001) higher than in sedentary subjects. The validity of the methodology was checked by the biological certified reference material. Trace element analysis concentrations, expressed in μg/mg creatinine, of five toxic elements in urine from athletes (n = 21) versus sedentary subjects, (n = 26) were as follows: Cd (0.123 ± 0.075 vs. 0.069 ± 0.041, P ≤ 0.05); W (0.082 ± 0.053 vs.

Total Ionising Dose (TID) effects are the most important effects of ionising radiation in MOS devices. Among others, TID cause charge trapping in the oxide and in the oxide-semiconductor interface. In this work we develop physical simulation models of charge trapping TID effects in MOS capacitors, in order to have a calculation model for postirradiation experiments. Simulations are made using the Sentaurus TCAD suite, comparing results with well established literature. We calculate the modifications in the C-V curve and the dependence of the flat band voltage due to charge trapping in the oxide, interface traps and the combination of both for increasing dose.

Particle radiation effects are a fundamental problem in the use of numerous electronic devices for space applications, which is aggravated with the technology shrinking towards smaller and smaller scales. The suitability of low-energy accelerators for irradiation testing is being considered nowadays. Moreover, the possibility to use a nuclear microprobe, with a lateral resolution of a few microns, allows us to evaluate the behavior under ion irradiation of specific elements in an electronic device. The CEICI is the new CEnter for Integrated Circuits Irradiation tests, created into the facilities at the Centro Nacional de Aceleradores (CNA) in Sevilla-Spain. We have verified that our 3 MV Tandem accelerator, typically used for ion beam characterization of materials, is also a valuable tool to perform irradiation experiments in the low LET (Linear Energy Transfer) region., The authors want to thank to the project RENASER (ESP2007-65914-C03-03) and to the project CEICI (ESP2007-65914-C03-02), both funded by the 2007 Research National Plan of the Spanish Ministry of Science and Education.

Comunicación presentada en the 11th European Conference on Radiation and its Effects on Components and Systems RADECS 2010, Längenfeld, Austria, September 20-24, 2010. A novel proposal to design radiation-tolerant embedded systems combining hardware and software mitigation techniques is presented. Two suites of tools are developed to automatically apply the techniques and to facilitate the trade-offs analyses. This work makes part of RENASER project (ESP2007-65914-C03-03) funded by the 2007 Spain Research National Plan of the Ministry of Science and Education in which context this work has been possible. The work presented here has been carried out thanks to the support of the research project ’Aceleración de algoritmos industriales y de seguridad en entornos críticos mediante hardware’ (GV/2009/098) (Generalitat Valenciana, Spain).

Technological advances of Field Programmable Gate Array (FPGA) are making that this technology becomes the most preferred platform for the rapid prototyping of highly integrated digital systems. In addition, protection of processor-based systems to mitigate the harmful effects of radiation-induced upset events is gaining importance while technology shrinks. In this context, the main contribution of this work is a novel rapid prototyping approach for the codesign of dependable embedded systems using FPGA. This is supported by a hardening platform that allows combining software-only fault-tolerance techniques with hardware-only approaches, representing several trade-offs among design constraints, reliability and cost. As case study, several radiation-tolerant embedded systems have been developed based on a technology-independent version of the Picoblaze processor. This work was funded by the Ministry of Science and Education in Spain with the RENASER project (ESP2007-65914-C03-03) and the Generalitat Valenciana in Spain with the research project ’Aceleración de algoritmos industriales y de seguridad en entornos críticos mediante hardware’ (GV/2009/098).

The protection of processor-based systems to mitigate the harmful effects of transient faults (hardening) is gaining importance as technology shrinks. Hybrid hardware/software hardening approaches are promising alternatives in the design of such fault tolerant systems. This paper presents a compiler-based infrastructure for facilitating the exploration of the design space between hardware-only and software-only fault tolerant techniques. The compiler design is based on a generic architecture that facilitates the implementation of software-based techniques, providing an uniform isolated-from-target hardening core. In this way, these methods can be implemented in an architecture independent way and can easily integrate new protection mechanisms to automatically produce hardened code. The infrastructure includes a simulator that provides information about memory and execution time overheads to aid the designer in the co-design decisions. The tool-chain is complemented by a hardware fault emulation tool that allows to measure the fault coverage of the different solutions running on the real system. A case study was implemented allowing to evaluate the flexibility of the infrastructure to fit the reliability requirements of the system within their memory and performance restrictions. This work makes part of RENASER project (ESP2007-65914-C03-03) funded by the 2007 Spain Research National Plan of the Ministry of Science and Education in which context this work has been possible. The work presented here has been carried out thanks to the support of the research project 'Aceleracióon de algoritmos industriales y de seguridad en entornos críticos mediante hardware' (GV/2009/098) (Generalitat Valenciana, Spain).

Simulation of pulsed laser single event effects (SEE) is not considered in most of the well known software packages for mixed-mode simulation of SEE. This paper shows an adaptation of the Sentaurus TCAD suite to pulsed laser SEE simulation. After the literature review, we present the virtual model of the target transistor, calibrated against a real transistor of an specific ASIC. That virtual model is used to evaluate the Linear Energy Transfer (LET) threshold for bitflip in a simulated flip-flop circuit using the heavy-ion simulation tools of TCAD. That simulations help us to make an adaptation of Sentaurus TCAD for simulation of pulsed laser experiments. The pulsed laser simulation results are compared with a laser pulse experiment, showing that the proposed model achieves more accuracy than previous models referred to in the literature.

Propagation Induced Pulse Broadening (PIPB) effect is becoming a major concern for electronic designers since new technologies are fast enough to propagate and capture Single Event Transients(SET). In this paper we explore the influence of the threshold voltage V T on PIPB effect by simulating the propagation of a SET through a self-feedback chain of CMOS inverters. The conclusions outlined are applicable when designing with Multi-Vt nanometric CMOS technologies.

Trends show that next coming technologies will produce new generations of very large circuits, running at high clock rates. Some critical applications will have to be protected against the remaining radiation at sea level. This is especially important in aerospace applications because ionizing radiation produces corruption of the internal state. New design methods have to be introduced to assure circuits will tolerate the impact of single event effects (SEE). It is very important to be able to analyze which parts of the circuits are more critical and how the behavior of the global system is degraded when one part suffers a SEE. This paper presents the last functionalities added to the FT-UNSHADES system to extend the analysis to SETs and MBUs. As a result, the system can insert and analyze many fault types at a rate of 180 K faults per hour in a system with 2 million test vectors.

Space application integrated circuits have large and complex validation process. One of the most expensive stage is the radiation test. There are few facilities qualified to satisfy the requirements of standards. Low power accelerators are used to simplify the validation process, because they usually have beam time, lower costs, and flexibility to access. As prevalidation tools they can provide valuable information about the circuit behavior. In this paper the first experience of irradiation to a silicon device during its execution in the Spanish National Accelerator Center is described. A radiation test using a semi-custom programmable (CPLD) commercial technology has been set-up. During this experience the CPLD has been irradiated with protons at 18 MeV while the device was running with a custom design. Results obtained are described and the damage over the device has been understood as total ionization dose.

Purpose: In the commissioning and QA of surface isotope-based applicators, source-indexer distance (SID) has a great influence in the flatness, symmetry and output. To these purposes, methods described in the literature are the use of a special insert at the entrance of dwell chamber or radiochromic films. Here we present the experience with a micro-chamber array to perform the commissioning and QA of Valencia applicators. Methods: Valencia applicators have been used, the classic and the new extra-shielded version. A micro-chamber array has been employed, 1000 SRS (PTW), with 977 liquid filled, 2.3×2.3×0.5 mm3 sized ion chambers covering 11×11 cm2, which spacing is 2.5 mm in the central 5.5×5.5 cm2, dedicated mainly in principle, in conjunction with Octavius 4D (PTW), to IMRT, VMAT, SBRT verifications. Verisoft software that allows for 3D and planar analysis has been used to evaluate the results. Applicators were located on the surface of the array. To verify the SID, measurements corresponding to the reference value, SID ± 1 mm and SID ± 2 mm were acquired (integration time was fixed in order to discard the influence of the source entrance/exit). Once SID was determined, standard protocol treatments corresponding to 3 Gy and 7 Gy were acquired in order to establish typical patient dose distribution. Results: The method is fast and sensitive. The SID obtained was 1321 mm which is the nominal value included in the applicator manual. For example at 1319 mm an asymmetry of ±8% with respect to the central value was measured, along with a central deviation of −4% referred to 1321 mm. Conclusion: A practical method for the commissioning and QA of Valencia applicators has been described. It has been shown that it is an efficient and accurate tool for these purposes as well as for the verification of the absolute output constancy.

Purpose: To study the performance of Dosimetry Check (DC), an EPID-based dosimetry software, which allows performing transit dosimetry, in low density medium, by comparing calculations in-phantom, and analysing results for 15 lung patients. Methods: DC software (v.3.8, pencil beam-based algorithm) has been tested, for plans (Eclipse v.10.0 TPS) delivered in two Varian Clinac iX equipped with aS1000 EPIDs.In the CIRS lung phantom, comparisons between DC and Eclipse (Acuros) were performed for several plans: (1) four field box; (2) square field delivered in arc mode; (3) RapidArc lung patient plan medially centred; (4) RapidArc lung patient plan centred in one lung. Reference points analysed: P1 (medial point, plans 1–3) and P2 (located inside one lung, plan 4).For fifteen lung patients treated with RapidArc, the isocentre and 9 additional points inside the PTV as well as the gamma passing rate (3%/3mm) for the PTV and at the main planes were studied. Results: In-phantom:P1: Per-field differences in plan 1: good agreement for AP-PA fields; discrepancy of 7% for the lateral fields. Global differences (plans 1–3): about 4%, showing a compensating effect of the individual differences.P2: Global difference (plan 4): 15 %. This represents the worst case situation as it is a point surrounded by lung tissue, where the DC pencil beam algorithm is expected to give the greater difference against Acuros.Lung patients: Mean point difference inside the PTV:(5.4±4.2) %. Gamma passing rate inside the PTV:(45±12) %. Conclusion: The performance of DC in heterogeneous lung medium was studied with a special phantom and the results for 15 patients were analysed. The found deviations show that even though DC is a highly promising in vivo dosimetry tool, there is a need of incorporating a more accurate algorithm mainly for plans with low density regions involved.

Purpose: With the establishment of the IGRT as a standard technique, the extra dose that is given to the patients should be taken into account. Furthermore, it has been a recent decrease of the dose threshold in the lens, reduced to 0.5 Gy (ICRP ref 4825-3093-1464 on 21st April, 2011).The purpose of this work was to evaluate the extra dose that the lens is receive due to the Cone-Beam (CBCT) location systems in Head-and-Neck treatments. Methods: The On-Board Imaging (OBI) v 1.5 of the two Varian accelerators, one Clinac iX and one True Beam, were used to obtain the dose that this OBI version give to the lens in the Head-and-Neck location treatments. All CBCT scans were acquired with the Standard Dose Head protocol (100 kVp, 80 mA, 8 ms and 200 degree of rotation).The measurements were taken with thermoluminescence (TLD) EXTRAD (Harshaw) dosimeters placed in an anthropomorphic phantom over the eye and under 3 mm of bolus material to mimic the lens position. The center of the head was placed at the isocenter. To reduce TLD energy dependence, they were calibrated at the used beam quality. Results: The average lens dose at the lens in the OBI v 1.5 systems of the Clinac iX and the True Beam is 0.071 and 0.076 cGy/CBCT, respectively. Conclusions: The extra absorbed doses that receive the eye lenses due to one CBCT acquisition with the studied protocol is far below the new ICRP recommended threshold for the lens. However, the addition effect of several CBCT acquisition during the whole treatment should be taken into account.

Purpose: To commission a new device for pre‐treatment patient specific verification of VMAT plans, which is capable of reconstructing 3D dose with high resolution. Methods: Octavius 4D system (PTW) consists of an ion chamber array embedded in a cylindrical phantom which, assisted by an inclinometer, rotates synchronously with the gantry. For VMAT plans, it measures planar dose distributions as a function of gantry angle in order to compute the resulting 3D dose distribution. There are two options for the ion chamber array: Octavius 729 (general purpose) and Octavius 1000 SRS (small field size, high resolution). We have used three linacs: two Varian Clinac iX and one TrueBeam with MLC HD 120, and the TPS has been Eclipse (v.10.0). The commissioning measurements consisted of the following tests: (1) homogeneity in response; (2) linearity with dose; (3) reproducibility; (4) leakage current, pre‐and post‐irradiation; (5) verification of typical VMAT and SBRT plans, comparing TPS‐calculated versus measured dose using 3D local gamma index (3%, 3 mm criteria). Results: We found the following results for Octavius 729 (and, in brackets, for Octavius 1000 SRS): (1) Homogeneity between chambers was 1.9% (0.8%). (2) Excellent linearity for both cases, with r2 value better than 0.999. (3) Reproducibility was 0.52% (0.08%). (4) Leakage increases with previously measured dose and shows its largest variation for large field sizes, fluctuating between −0.33 and +0.33 cGy/min (between −0.006 and +0.020 cGy/min). (5) Verifications of typical clinical plans, performed with the adequate array, showed a mean pass ratio of 89.3% (98.7%). Conclusion: Octavius 4D system together with Octavius 729 is an adequate tool for VMAT patient specific QA. With Octavius 1000 SRS, this capability is extended to those treatments requiring better resolution, as is the case for SBRT.

Purpose: The aim of this work is to study the differences of reference point doses between the commercial EPID based dosimetry software Dosimetry Check (DC) and TPS to establish an accuracy level of the system, to evaluate its use in clinical routine and to obtain results for the first patients. Methods: We used DC v.3.8 (Math Resolutions), two Varian Clinac iX accelerators equipped with EPID aS1000 and Eclipse v.10.0 with AAA algorithm. Several plans with and without air gap were generated over the phantoms: MP1 Water Tank and Solid Octavius 4D (PTW). 5 head and neck, 3 lung and 4 prostate cases were selected for clinical evaluation. We compared the calculated dose at the isocenter and in a set of 9 points distributed in the PTV and made a gamma analysis of the 3D volume in pre‐treatment mode and during 3 CBCT‐guided sessions in transit mode. Results: In the study with phantoms, total dose differences in the isocenter between DC and TPS are less than 2%, but single field contributions achieve greater values. In transit mode, DC does not consider properly the couch attenuation, especially when there is an air gap between phantom and couch. For patients, better results are observed for prostate than for lung (heterogeneities) or head and neck (heterogeneities, field size). Information is lost in edges of large fields due to the limitation in EPID size and in the event of an interruption during treatment. Conclusion: Tests carried out with phantoms suggest that the accuracy of DC achieves 2% for total dose. For off‐axis dose distribution, and also for patients, this uncertainty results significantly higher. In any case, the possibility of this in vivo evaluation and the potentiality of this new system have a very positive impact on improving patient QA.

Thirty one amateur skiers with 33 knees which had had a symptomatic chronic rupture of the anterior cruciate ligament (ACL) treated with the Lemaire operation were reviewed retrospectively at an average of 4.5 years. Of the patients 23 were women. The operation failed to control symptoms in 17 out of the 33 knees. However the operation did control symptoms in 13 out of 19 knees in patients over 35 years old, compared with only three out of 14 knees in patients under 35 years old. Clinical and objective testing however showed that most knees were still unstable. Despite this 21 patients continued skiing. One patient with a successful result switched to playing tennis. Five patients gave up all sports. Four further patients, all under 35 years old, returned to skiing after an additional intra-articular reconstruction of the anterior cruciate ligament. An isolated extra-articular procedure in amateur skiers under 35 years old with symptomatic chronic ACL rupture is not recommended. They need at least an intra-articular reconstruction to control their symptoms and to stabilize the knee.

The correlations between lipid and lipoprotein measurements and other risk factors of coronary artery disease were evaluated in 101 men undergoing coro nary angiography. Clinically significant disease was present in 75 patients, whereas 24 had no observable lesions and 2 had minimal lesions. Comparisons of individual lipid and lipoprotein levels were nearly all significantly different between patients with and patients without clinically significant disease; how ever, no single variable could predict the presence of disease among patients. Logistic regression analysis identified five factors: apolipoprotein A-I, apolipo protein B, diabetes, age, and family history of heart disease, which account for most of the differences between the two patient groups. These results could have important implications for the evaluation and management of patients sus pected of having coronary atherosclerosis.

Data from 518 consecutive cardiac catheterizations were analyzed to test the value of prophylactic pacemaker insertion during coronary angiography and to compare the incidence of arrhythmic complications in patients with and without pacemakers. In patients without pacing (n = 273), 1 episode of ventricular fibrillation occurred, which responded promptly to defibrillation. Sinus bradycardia (fewer than 30 beats/min for 10 seconds) was recorded in 74 patients (27%) and required treatment in 30 (11%). No patient required or would have benefited from pacemaker placement. Of the 245 patients with prophylactic pacemakers, there was an increased incidence of all ventricular (9 vs 1; p less than 0.013) and supraventricular (5 vs 0; p less than 0.046) arrhythmias. Pacemaker-associated induction of ventricular fibrillation occurred in 2 patients and was clearly related to electrical stimulation during a normally non-vulnerable period of the cardiac cycle. In conclusion, routine prophylactic pacemaker insertion during coronary angiography is not warranted in patients with normal sinus rhythm and normal atrioventricular conduction. More information is needed to determine if pacing is needed in patients with conduction system disease.

Clinical, angiographic, and pathologic data support the contention that atherosclerosis, platelet aggregation, and coronary vasomotility work in unison to cause coronary thrombosis, which in turn leads to myocardial infarction. A patient is described in whom, 2 months after an acute myocardial infarction, inducible coronary artery spasm and a nonocclusive thrombus were angiographically demonstrated at the site of a minimal atherosclerotic narrowing in the infarction-related vessel. This report, to the best of our knowledge, is the first time that these three pathophysiologic mechanisms have been shown, in vivo, to be occurring concomitantly in an infarct-related vessel. Documentation of the unified occurrence of these phenomena support the current concept of the pathophysiology of myocardial infarction.

Seven normal, 7 paraplegic and 7 quadriplegic patients underwent cross-sectional cardiovascular evaluation, including recording of sitting heart rate, blood pressure and echocardiography. Quadriplegic patients had a 26% lower left ventricular (LV) mass index (75 +/- 13 g/m2, p less than 0.01) compared with normal volunteers (102 +/- 16 g/m2) or paraplegic patients (110 +/- 26 g/m2). Six quadriplegic patients and 3 paraplegic patients had an unusual pattern of LV posterior wall asynergy, which was associated with a significant rightward shift of the frontal-plane QRS axis (92 +/- 22 degrees vs 42 +/- 41 degrees, p less than 0.005) and smaller left atrial dimensions (2.4 +/- 0.4 vs 3.0 +/- 0.3 cm, p less than 0.005). The quadriplegic group was characterized by a significantly reduced mean blood pressure (67 +/- 7 vs 88 +/- 8 mm Hg in normal subjects, p less than 0.002), high normal peripheral resistances (22 +/- 5 vs 17 +/- 5 units in normal subjects, difference not significant) and a markedly reduced calculated cardiac output (3.2 +/- 0.6 vs 5.4 +/- 1.4 liters/min in normal subjects, p less than 0.01). Hemodynamic data for the paraplegic patients were similar to those in the normal group. A decrease in LV wall stress, mediated primarily by a decrease in venous return, appeared to result in the "adaptive" cardiac atrophy seen in these quadriplegic patients. LV asynergy was common and also may be related to a decrease in cardiac filling.