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ABSTRACT: The aim of the study was to assess the consequences of early and systematic nutritional intervention on the clinical conditions of amyotrophic lateral sclerosis (ALS) patients and on the opportunity to maintain a good nutritional status for as long as possible.
Thirty-three subjects with ALS. Protocol Group: 12 subjects (9 M and 3 F) monitored according to a precise nutritional intervention protocol. Control Group: 21 subjects (10 M and 11 F) monitored before applying the protocol.
Data recorded at the time of initial assessment were compared and expressed as the mean ± standard deviation for the Protocol Group vs. the Control Group: BMI (kg/m2) 23.6±4.1 vs. 21.6±3.5; weight loss as a percentage of usual weight 6.6±7.9 vs. 16.3±8.8 (P=0.003). At six months: weight loss as a percentage of usual weight 4.9±6.2 vs. 16.9±10.2 (P=0.002). At 12 months: weight loss as a percentage of usual weight 7.3±7.1 vs. 17.5±11.1 (P=0.03). At the first follow-up visit, fewer patients in the Protocol Group were receiving enteral nutrition (25%) than patients in the Control Group (60%). At six-month follow-up visit: 30% vs. 68%. Standard enteral nutrition formulas were used. One year after initial assessment, the mortality rate was 17% for the Protocol Group, whereas it was 24% at six months and 33% after one year for the Control Group.
If patients are treated before any significant weight loss occurs, early and specific nutritional intervention allows good nutritional status to be maintained for a longer period; if artificial nutrition is required, standard diets are able to ensure adequate clinical results.
Minerva gastroenterologica e dietologica 09/2012; 58(3):253-60.
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ABSTRACT: The corruption of the information stored in floating gate cells due to heavy-ion strikes is a critical issue for the use of Flash memories in space. In this work we examine how feature size scaling affects the single event upset sensitivity of multi-level floating gate cells with NAND architecture. Both experimental data on heavy-ion irradiation and analytical modeling are used to study how the threshold LET and saturation cross section depend on the cell feature size. A comparison is also carried out between multi-level and single-level floating gate cells.
IEEE Transactions on Nuclear Science 07/2011; · 1.45 Impact Factor
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ABSTRACT: Electronic chips working in the space environment are constantly subject to both single event and total ionizing dose effects. To emulate this scenario for Flash memories, we tested under heavy ions floating gate cells, previously irradiated with x-rays, without performing any erase and program operation in between the two exposures. We observed an increase in the heavy-ion upset cross section in the devices that were submitted to TID irradiations, especially at low LETs. This effect is attributed to the combination of the threshold voltage shifts induced by heavy ions and x-rays. Implications for the hardness assurance of Flash memories are discussed.
IEEE Transactions on Nuclear Science 01/2011; · 1.45 Impact Factor
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ABSTRACT: We studied heavy-ion effects on floating gate memories, focusing on the generation of tails in the threshold voltage distributions after irradiation. Using both experiments and simulations based on the Geant4 toolkit, we provide new insight, distinguishing two types of events, large events and small events, which are responsible for the secondary peak and the intermediate region in the post-rad threshold distribution, respectively. Both are well correlated with the energy deposited in the FG. Implications for error rate predictions are discussed.
IEEE Transactions on Nuclear Science 01/2011; · 1.45 Impact Factor
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ABSTRACT: We discuss non-volatile memories (NVM) for space applications. The focus will be both on technologies and devices aimed at the mainstream commercial markets and on rad-hard devices. Commercial NVMs are very attractive for space designers due to their large size (tens of Gbits), even though they have several issues related to ionizing radiation. Rad-hard NVMs offer radiation hardness, but are available only in small size (few Mbits). Most of the emphasis in this review paper will be on the current dominant technology in the mainstream market: floating gate flash memories. A comprehensive discussion of total dose and single event effects results for a wide cross section of NVMs will be presented. Finally, we will conclude with a cursory glance at other emerging non-volatile technologies.
IEEE Transactions on Nuclear Science 01/2011; · 1.45 Impact Factor
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ABSTRACT: We analyzed the impact of negative bias temperature instability (NBTI) on the single-event upset rate of SRAM cells through experiments and SPICE simulations. We performed critical charge simulations introducing different degradation patterns in the cells, in three technology nodes, from 180 to 90 nm. The simulations results were checked with α-particle and heavy-ion irradiations on a 130-nm technology. Both simulations and experimental results show that NBTI degradation does not significantly affect the single-event upset SRAM cell rate as long as the parametric drift induced by aging is within 10%.
IEEE Transactions on Nuclear Science 01/2011; · 1.45 Impact Factor
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ABSTRACT: Swift heavy ions impacting on matter lose energy through the creation of dense tracks of charges. The study of the space and time evolution of energy exchange allows understanding the single event effects behavior in advanced microelectronic devices. In particular, the shrinking of minimum feature size of most advanced memory devices makes them very interesting test vehicles to study these effects since the device and the track dimensions are comparable; hence, measured effects are directly correlated with the time and space evolution of the energy release. In this work we are studying the time and space evolution of ion tracks by using advanced non volatile memories and Monte Carlo simulations. Experimental results are very well explained by the theoretical calculations.
Journal of Applied Physics 12/2010; 108(12):124907-124907-19. · 2.17 Impact Factor
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ABSTRACT: We discuss the room temperature annealing of Floating Gate errors in Flash memories with NAND and NOR architecture after heavy-ion irradiation. We present the evolution of raw bit errors as a function of time after the exposure, examining the annealing dependence on the particle LET, cell feature size, and, for Multi Level Cells, on the program level. The results are explained based on the statistical properties of the cell threshold voltage distributions before and after heavy-ion strikes.
IEEE Transactions on Nuclear Science 09/2010; · 1.45 Impact Factor
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ABSTRACT: We studied the short- and long-term effects of heavy-ion strikes on silicon-on-insulator (SOI) FinFET devices manufactured in a sub 32-nm CMOS process. The degradation of the device DC characteristics after irradiation strongly depends on the incidence angle, strain, and channel type, depending on the balance between damage to the high-k gate oxide and to the buried oxide. The time-dependent dielectric breakdown (TDDB) and the device parameter degradation kinetics are affected by the LET, ion fluence, and incidence angle. A reduction in TDDB is observed in irradiated FinFETs with respect to unirradiated ones.
IEEE Transactions on Nuclear Science 09/2010; · 1.45 Impact Factor
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ABSTRACT: This paper presents and discusses the results of Alpha Single Event Upset (SEU) tests on an embedded 8051 microprocessor core implemented using three different standard cell libraries. Each library is based on a different Design for Manufacturability (DfM) optimization strategy; our goal is to understand how these strategies may affect the device sensitivity to alpha-induced Soft Errors. The three implementations are tested resorting to advanced Design for Testability (DfT) methodologies and radiation experiments results are compared. Electrical simulations of flip-flops are finally performed to propose physical motivations to the observed phenomena.
IEEE Transactions on Nuclear Science 09/2010; · 1.45 Impact Factor
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ABSTRACT: We present new experimental results on heavy ion-induced gate rupture on deep submicron CMOS transistor arrays. Through the use of dedicated test structures, composed by a large number of 130-nm MOSFETs connected in parallel, we show the response to heavy ion irradiation under high stress voltages of devices previously irradiated with X-rays. We found only a slight impact on gate rupture critical voltage at a LET of 32 MeV cm<sup>2</sup> mg<sup>-1</sup> for devices previously irradiated up to 3 Mrad(SiO<sub>2</sub>), and practically no change for 100 Mrad(SiO<sub>2</sub>) irradiation, dose of interest for the future super large hadron collider (SLHC).
IEEE Transactions on Nuclear Science 09/2010; · 1.45 Impact Factor
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ABSTRACT: This paper reports and analyzes the results of alpha radiation testing campaigns on an embedded microprocessor manufactured with different standard cell libraries, each one enforcing Design for Manufacturing rules at a specific level. A set of analog simulations has been performed on flip-flops built with different physical layouts to reproduce and evaluate the effects of ionizing particles. The results of simulation experiments are presented and discussed, highlighting the configurations which are more likely to improve the system reliability, and then compared with radiation experiments data. Finally, we give a physical interpretation of the observed variations on radiation sensitivity.
On-Line Testing Symposium (IOLTS), 2010 IEEE 16th International; 08/2010
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ABSTRACT: We investigate atmospheric neutron effects on floating gate cells in MLC NAND Flash memories. Loss of information is shown to occur especially at the highest program levels, but to an extent that does not challenge current error correction capabilities. We discuss the physical mechanisms and analyze scaling trends, which show a rapid increase in sensitivity for decreasing feature size. A large spread in the cross section is visible from vendor to vendor for comparable feature size.
Reliability Physics Symposium (IRPS), 2010 IEEE International; 06/2010
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A A Abdo,
M Ackermann,
M Ajello,
A Allafort,
E Antolini,
W B Atwood,
M Axelsson,
L Baldini,
J Ballet,
G Barbiellini, [......],
V Vitale,
A P Waite,
E Wallace,
P Wang,
K Watters,
B L Winer,
K S Wood,
Z Yang,
T Ylinen,
M Ziegler
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ABSTRACT: We present a catalog of high-energy gamma-ray sources detected by the Large Area Telescope (LAT), the primary science instrument on the Fermi Gamma-ray Space Telescope (Fermi), during the first 11 months of the science phase of the mission, which began on 2008 August 4. The First Fermi-LAT catalog (1FGL) contains 1451 sources detected and characterized in the 100 MeV to 100 GeV range. Source detection was based on the average flux over the 11 month period, and the threshold likelihood Test Statistic is 25, corresponding to a significance of just over 4 sigma. The 1FGL catalog includes source location regions, defined in terms of elliptical fits to the 95% confidence regions and power-law spectral fits as well as flux measurements in five energy bands for each source. In addition, monthly light curves are provided. Using a protocol defined before launch we have tested for several populations of gamma-ray sources among the sources in the catalog. For individual LAT-detected sources we provide firm identifications or plausible associations with sources in other astronomical catalogs. Identifications are based on correlated variability with counterparts at other wavelengths, or on spin or orbital periodicity. For the catalogs and association criteria that we have selected, 630 of the sources are unassociated. Care was taken to characterize the sensitivity of the results to the model of interstellar diffuse gamma-ray emission used to model the bright foreground, with the result that 161 sources at low Galactic latitudes and toward bright local interstellar clouds are flagged as having properties that are strongly dependent on the model or as potentially being due to incorrectly modeled structure in the Galactic diffuse emission.
The Astrophysical Journal Supplement Series 06/2010; 188(2):405-436. · 13.46 Impact Factor
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ABSTRACT: Heavy ion single-event measurements on a variety of high density commercial NAND flash memories are reported. Three single event effect (SEE) phenomena were investigated: single effect upsets (SEUs), single effect functional interrupts (SEFIs), and a new high current phenomenon which at high LETs results in catastrophic loss of ability to erase and program the device.
IEEE Transactions on Nuclear Science 03/2010; · 1.45 Impact Factor
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Microelectronics (ICM), 2010 International Conference on; 01/2010
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ABSTRACT: We study the variability of microdose effects induced by heavy-ion strikes on FinFETs. We model the effects through a statistical analysis, which considers the three-dimensional nature of these devices and overlapping ion hits. The analysis carried out in this work is based on a large amount of experimental data and on the reliability distribution functions (Poisson area scaling, LogNormal distribution, Weibull distribution, etc.), commonly used to estimate the time and charge to breakdown for accelerated lifetime tests.
IEEE Transactions on Nuclear Science 01/2010; · 1.45 Impact Factor
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ABSTRACT: We discuss new experimental results on the post-radiation annealing of Floating Gate errors in Flash memories with both NAND and NOR architecture. We investigate the dependence of annealing on the program level, linking the reduction in the number of Floating Gate errors to the evolution of the threshold voltage of each single cell. To understand the underlying physics we also discuss how temperature affects the number of Floating Gate errors.
IEEE Transactions on Nuclear Science 01/2010; · 1.45 Impact Factor
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ABSTRACT: We have investigated the effects of biased and unbiased X-ray irradiation on the subsequent time-dependent dielectric breakdown (TDDB) of 130-nm MOSFETs irradiated up to 1Mrad(SiO<sub>2</sub>). We found a small but measurable increase in TDDB lifetime after irradiation at the worst-case irradiation bias. The influence of radiation bias on subsequent TDDB is more significant in the PMOSFETs than the NMOSFETs. The increased TDDB lifetime and the irradiation-bias dependence are attributed to the influence of radiation-induced traps on the stressing current during the reliability testing.
IEEE Transactions on Nuclear Science 01/2010; · 1.45 Impact Factor
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ABSTRACT: Flash-based FPGAs are more and more interesting for space applications because of their robustness against Single Event Upsets (SEUs) in configuration memory. However, as Single Event Effects (SEEs) are still a concern both for user memory and the configurable logic, accurate evaluations are needed to identify mitigation techniques for securing their use in space missions. In this paper the SEE sensitivity of circuits implemented in Flash-based FPGAs is evaluated with respect to the working frequency and different routing schemes. We outline different methodologies that can be used in order to characterize SEE sensitivity, using both heavy-ions radiation experiments and analytical approaches. Experimental results detail the contributions of different SEEs as a function of operating frequency and routing on a realistic circuit.
IEEE Transactions on Nuclear Science 01/2010; · 1.45 Impact Factor
