185 research outputs found
Study of Warm Electron Injection in Double Gate SONOS by Full Band Monte Carlo Simulation
In this paper we investigate warm electron injection in a double gate SONOS
memory by means of 2D full-band Monte Carlo simulations of the Boltzmann
Transport Equation (BTE). Electrons are accelerated in the channel by a
drain-to-source voltage VDS smaller than 3 V, so that programming occurs via
electrons tunneling through a potential barrier whose height has been
effectively reduced by the accumulated kinetic energy. Particle energy
distribution at the semiconductor/oxide interface is studied for different bias
conditions and different positions along the channel. The gate current is
calculated with a continuum-based post-processing method as a function of the
particle distribution obtained from Monte Carlo. Simulation results show that
the gate current increases by several orders of magnitude with increasing drain
bias and warm electron injection can be an interesting option for programming
when short channel effects prohibit the application of larger drain bias
Spontaneous Endoreduplication, Tetraploidy and Chromosome Breakage in Lymphocyte Cultures from Healthy Subjects
SUMMARY42,703 metaphases of peripheral lymphocytes from 20 healthy subjects (10 women and 10 men) were examined in order to establish the frequency of endoreduplicated cells and of tetraploid cells without diplochromosomes. Frequencies were found to be 0.016% and 0.112%, respectively. The two sexes did not differ as to the frequency of tetraploid cells, with and without diplochromosomes (about 0.13% in either sex). In a total of 2,135 well spread metaphases examined, 26 cells (i.e. 1.2%) with chromosomal breaks were found. Again, no significant differences between the two sexes were found as to such chromosome abnormalities
Transient Analysis of Warm Electron Injection Programming of Double Gate SONOS Memories by means of Full Band Monte Carlo Simulation
In this paper we investigate "Warm Electron Injection" as a mechanism for NOR
programming of double-gate SONOS memories through 2D full band Monte Carlo
simulations. Warm electron injection is characterized by an applied VDS smaller
than 3.15 V, so that electrons cannot easily accumulate a kinetic energy larger
than the height of the Si/SiO2 barrier. We perform a time-dependent simulation
of the program operation where the local gate current density is computed with
a continuum-based method and is adiabatically separated from the 2D full Monte
Carlo simulation used for obtaining the electron distribution in the phase
space. In this way we are able to compute the time evolution of the charge
stored in the nitride and of the threshold voltages corresponding to forward
and reverse bias. We show that warm electron injection is a viable option for
NOR programming in order to reduce power supply, preserve reliability and CMOS
logic level compatibility. In addition, it provides a well localized charge,
offering interesting perspectives for multi-level and dual bit operation, even
in devices with negligible short channel effects
Aestivation and hypoxia-related events share common silent neuron trafficking processes
10.1186/1471-2202-13-39BMC Neuroscience131-BNME
Neutralization of IFN-γ reverts clinical and laboratory features in a mouse model of macrophage activation syndrome.
BACKGROUND: The pathogenesis of macrophage activation syndrome (MAS) is not clearly understood: a large body of evidence supports the involvement of mechanisms similar to those implicated in the setting of primary hemophagocytic lymphohistiocytosis.
OBJECTIVE: We sought to investigate the pathogenic role of IFN-γ and the therapeutic efficacy of IFN-γ neutralization in an animal model of MAS.
METHODS: We used an MAS model established in mice transgenic for human IL-6 (IL-6TG mice) challenged with LPS (MAS mice). Levels of IFN-γ and IFN-γ-inducible chemokines were evaluated by using real-time PCR in the liver and spleen and by means of ELISA in plasma. IFN-γ neutralization was achieved by using the anti-IFN-γ antibody XMG1.2 in vivo.
RESULTS: Mice with MAS showed a significant upregulation of the IFN-γ pathway, as demonstrated by increased mRNA levels of Ifng and higher levels of phospho-signal transducer and activator of transcription 1 in the liver and spleen and increased expression of the IFN-γ-inducible chemokines Cxcl9 and Cxcl10 in the liver and spleen, as well as in plasma. A marked increase in Il12a and Il12b expression was also found in livers and spleens of mice with MAS. In addition, mice with MAS had a significant increase in numbers of liver CD68+ macrophages. Mice with MAS treated with an anti-IFN-γ antibody showed a significant improvement in survival and body weight recovery associated with a significant amelioration of ferritin, fibrinogen, and alanine aminotransferase levels. In mice with MAS, treatment with the anti-IFN-γ antibody significantly decreased circulating levels of CXCL9, CXCL10, and downstream proinflammatory cytokines. The decrease in CXCL9 and CXCL10 levels paralleled the decrease in serum levels of proinflammatory cytokines and ferritin.
CONCLUSION: These results provide evidence for a pathogenic role of IFN-γ in the setting of MAS
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Amperometric Biosensor and Front-End Electronics for Remote Glucose Monitoring by Crosslinked PEDOT-Glucose Oxidase
Focusing on the interplay between interface chemistry, electrochemistry, and integrated electronics, we show a novel low-cost and flexible biosensing platform for continuous glucose monitoring. The amperometric biosensing system features a planar three-electrode structure on a plastic substrate, and a wireless near-field communication-powered electronic system performing sensor analog front-end, A/D conversion, digital control, and display tasks. The working electrode is made of electropolymerized poly (3,4-ethylenedioxythiophene) film onto a polyethylene terephthalate/gold electrode followed by immobilization of cross-linked glucose oxidase by glutaraldehyde. The advantages offered by such a device, including low-cost materials and instrumentation as well as the good sensitivity of 9.24 \mu \text{A}/({\mathrm {mM}} \cdot {\mathrm {cm}}^{2}) are promising tools for point-of-care monitoring. It is demonstrated that the devices are good candidates for the development of advanced sensing approaches based on the investigation of the noise produced during operation (fluctuation-enhanced sensing).Luig
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