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In today’s market place a trend is in place to move from MIL- STANDARD (MIL-STD) to Commercial off the Shelf (COTS) equipment as cost becomes a major driver in our military procurements. While it may have been sufficient in the past to focus on extensive classical reliability and maintainability testing methods of complex models as the primary method for ensuring the procurements had a high degree of reliability these methods today in the in procurement of COTS equipment is receiving push back from many of the COTS vendors.

CEA and Sofradir have been involved for 7 years in studies related to a large format detector development for science and astronomy applications. These studies are linked with ESA's Near Infrared Large Format Sensor Array roadmap which aims to develop a 2Kx2K large format low flux low noise device. The ALFA (Astronomical Large Focal plane Array) detector is currently at design, manufacturing and validation phase at CEA and Sofradir. This paper will present the very last achievements of the ALFA development with a specific focus on the readout integrated circuit design itself. Features and specification of the 2048x2048 15μm pitch with Source Follower Detector (SFD) input stage will be described. Apart from ESA development, European Commission is also contributing to the large detector development thanks to ASTEROID (AStronomical TEchnology EuROpean Infrared detector Development) program founded by REA (Research European Agency). ASTEROID main objectives are to develop very large raw materials (CdZnTe substrate, HgCdTe epilayer…) compatible with the manufacturing of very large detectors in volume keeping the same level of performance. Organization and status of this program will be presented where high synergy with 2K² ALFA detector are included.

A backscattering model suitable for compact modeling of nanoscale MOSFET is developed within the Landauer flux-scattering theory. To describe the quasi-ballistic transport, a new backscattering model based on the accurate determination of ballistic and backscattering probabilities along the channel is developed. This model is based on a careful analysis of transport in device using Monte Carlo simulation. This model allows us to display the main physical quantities along the channel and to accurately describe the quasi-ballistic transport and its effects on current-voltage characteristics.

Purpose. Endothelium insulin permeability was investigated using in vitro, dynamic culture of endothelial cells. Methods. Endothelial cells were cultured in a hollow fiber apparatus and continuously exposed to a flow. Transendothelial electrical resistance and permeability to [14C]sucrose and [14C]inulin were used to monitor the integrity of the endothelial monolayer. Results. Under these experimental conditions, measurements of insulin permeability, investigated at increasing hormone concentrations, suggested that the predominant transendothelial insulin fluxes were attributable to bidirectional convective transport rather than to a saturable transport mechanism, in agreement with in vivo experiment results published earlier. Analytical determinations of insulin catabolism demonstrated a low percent of insulin degradation by the endothelium, leading to production of insulin metabolites qualitatively identical to those produced by human monocytes. Conclusions. The findings of this paper indicated that (a) insulin crosses the endothelial monolayer by paracellular “leak” and endothelial insulin receptors have a minor (if any) role in insulin transport; (b) degradation of the hormone by BAEC is minimal; (c) the in vitro, dynamic culture of endothelial cells presented here should represent a valuable transport model system to study permeability mechanisms of insulin and many other drugs.

Strong evidence is emerging that mitochondrial permeability transition (MPT) may be important in certain physiological conditions and, above all, in the processes of cell damage and death. Reversible MPT, triggered by inducing agents in the presence of calcium ions, has resulted in the opening of a dynamic multiprotein complex formed in the inner mitochondrial membrane and has caused large-amplitude mitochondrial swelling. In the present work, the exposure of de-energized rat cardiac mitochondria to peripheral benzodiazepine receptor (PBR) ligands (1-(2-chlorophenyl-N-methyl-1-methylpropyl)-3-isoquinolinecarboxamide (PK 11195), 7-chloro-5-(4-chlorophenyl)-1,3-dihydro-1-methyl-2H-1,4-benzodiazepin-2-one (Ro5-4864), and diazepam) produced a dose-dependent and cyclosporin A (CSP)-sensitive loss of absorbance, which was indicative of mitochondrial swelling. By contrast, the addition of a high-affinity central benzodiazepine receptor ligand (clonazepam) was ineffective, even at the highest concentration tested. The ultrastructural changes associated with swelling were similar in mitochondria exposed either to PK 11195 or to calcium. Supporting the apoptotic role of PK 11195-induced swelling, supernatants from mitochondria that had undergone permeability transition caused apoptotic changes in isolated cardiac nuclei. In addition, ultrastructural abnormalities were observed in rat cardiac tissue following in vivo PK 11195 administration, with these abnormalities being prevented by CSP co-administration. These data indicate that PBR ligands induce mitochondrial permeability transition and ultrastructural alterations in isolated cardiac mitochondria as well as in myocardiocytes, suggesting a novel strategy for studying the implication of PBR ligands as apoptosis inducers, through a probable effect on the MPT pore.

By occupying specific surface receptors, adenosine and adenosine analogues modulate neutrophil functions; in particular, functional and biochemical studies have shown that A(1) adenosine receptors modulate chemotaxis in response to chemotactic peptides. Until now, the characteristics of the specific agonist binding and the visualization of A(1) receptors in human neutrophils have not been investigated. In the present study, we used the agonist [(3)H] CHA for radioligand binding studies and a CHA-biotin XX probe in order to visualize the A(1) binding sites in human neutrophils, ultrastructurally, by conjugation with colloidal gold-streptavidin. [(3)H] CHA bound A(1) adenosine receptors with selectivity and specificity, although with a low binding capacity. Scatchard analysis showed a Kd value of 1.4 +/- 0.08 nM and a maximum density of binding sites of 7.1 +/- 0.37 fmol/mg of proteins. The good affinity and selectivity of the CHA-biotin XX probe for A(1) adenosine receptors allowed us to visualize them, after conjugation with colloidal gold-streptavidin, as electron-dense gold particles on the neutrophil surface and inside the cell. The internalization of the ligand-receptor complex was followed in a controlled temperature system, and occurred through a receptor-mediated pathway. The kinetics of the intracellular trafficking was fast, taking less than 5 min. These data suggest that the CHA-biotin XX-streptavidin-gold complex is a useful marker for the specific labelling of A(1) binding sites and to follow the intracellular trafficking of these receptors.

Anxioselective agents may be identified among compounds binding selectively to the alpha(2)beta(x)gamma(2) subtype of the gamma-aminobutyric acid-A (GABA(A))/central benzodiazepine receptor (BzR) complex and behaving as agonists or among compounds binding with comparable potency to various BzR subtypes but eliciting agonism only at the alpha(2)beta(x)gamma(2) receptor. Because of subtle steric differences among BzR subtypes, the latter approach has proved much more successful. A biological screening within the class of indol-3-ylglyoxylamides 1-3 allowed us to identify compounds 1c and 2b as potential anxiolytic/nonsedative agents showing alpha(2) selective efficacy in vitro and anxioselective effects in vivo. According to molecular modeling studies, and consistently with SARs accumulated in the past decade, 5-NO(2)- and 5-H-indole derivatives would preferentially bind to BzR by placing the indole ring in the L(Di) and the L(2) receptor binding sites, respectively.

This study presents the use of atomistic process simulations to optimize p+/n ultra-shallow junctions fabrication process. We first bring to the fore that a high injection of interstitials close to the boron profile decreases the sensibility of boron diffusion to thermal budget. Preamorphization of the substrate is thus necessary to decrease boron diffusion by thermal budget reduction, the latter being obtained by the use of the thermal conduction tool (Levitor) instead of the classical lamp-type rapid thermal annealing. At the same time we show that the use of Levitor does not enhance boron activation, the substrate being preamorphize or not. So Levitor anneal can improve sheet resistance/junction depth trade-off only with preamorphization implant. Experiments are performed that confirm the predictions of our simulations. Further discussions explain activation path of boron during temperature cycle, as a function of amorphous depth, and for both lamp-type and Levitor anneal.

This study is aimed to understand the mechanisms leading to different device behaviors while switching from one type of implanter, which scans a batch of wafers with a spot ion beam, to another one, which scans a single wafer with a ribbon ion beam. Thanks to atomistic simulations, we bring to the fore that the implant dose rate is responsible for the observed mismatch. Increasing the dose rate reduces the amount of interstitials present beyond the amorphous layer. During subsequent annealing, these interstitials first accelerate boron clusters dissolution at projected range, then agglomerate themselves into stable dislocation loops. The latter will in turn deactivate the boron in source and drain region, modifying the electrical characteristics of the device.

The fully depleted (FD) SOI MOSFET is generally considered as one of the best candidates for next CMOS technology nodes. However, new technological boosters need to be introduced in the classical FD SOI process flow to reach the very aggressive Ion/Ioff specifications predicted by the ITRS roadmap. The use of a thin buried oxide (BOX) on FD SOI is still a controversial subject, despite recent publications that have demonstrated its interest for improvement of short channel effect (SCE) control, especially with a ground plane (GP) integration (Tsuchiya et al.). In order to improve the device performances, a strained "contact etch stop layer" (CESL) technique has been successfully demonstrated to induce strain into the channel of bulk devices (Thompson et al., 2002) as well as in ultra-thin FD SOI devices (Singh et al., 2005 and Gallon et al., 2006). However, its compatibility with the specific technological features of FD SOI devices, such as silicon film thickness (TS1) variations, BOX material and BOX thickness (TBOX), raised source/drain architecture, has yet to be clarified. In this paper, we demonstrate, by electrical and mechanical simulations, the interest of thin BOX with GP, combined with a strained liner. These simulations have then been validated by measurements, showing excellent Ion/Ioff pMOS performances

This work highlights the realization and 0.248/spl mu/m/sup 2/ to 0.334/spl mu/m/sup 2/ SRAM bit-cells with conventional bulk technology based on 19/spl Aring/ CET SiON gate oxide, poly-silicon gate electrode, and mobility enhancement techniques for both nMOS and pMOS. High density critical lithography levels have been exposed with e-beam direct writing thus contributing to the overall cost-effectiveness of the technology.

This paper demonstrates that, for NMOS, the use of LSA and smart junction engineering enable to improve dramatically short channel effects (-65% in DIBL at L/sub g/=45 nm due to lower X/sub j/ and DL) and I/sub on//I/sub off/ performance (+7% I/sub on/ at I/sub off/=100 nA//spl mu/m due to steeper sub-threshold slope and reduced poly-depletion) compared to spike annealed N-MOSFETs. These results show the potential advantage of ultra-high temperature and non diffusive annealing such as LSA that may be necessary for the 45 nm technology and below.

In this paper, simple corrections to traditional Drift-Diffusion mobility models are derived from strained full-band Monte Carlo simulations in order to correctly account for strain effects. The validity of this approach is benchmarked upon Monte Carlo MOSFET simulations as well as experimental data featuring tensile nitride capping layers.

Plasma doping (PLAD) is an ion implantation technique under investigation to realize ultra-shallow junctions for 65 nm nodes and beyond. This technique has been modelled and is integrated in TCAD process simulation tools. The most influential parameters of PLAD have been isolated. With these parameters, a design of experiments (DOE) has been performed to interpolate a quadratic surface response model of PLAD profiles. Boron implantations were studied in the range from 1 to 8 keV and 1e15 to 5e15at/cm/sup 2/. Accuracy is very good on the whole range of parameter variations. 2D process simulations are finally shown.

This work highlights a 65 nm CMOS technology platform for low power and general-purpose applications. A 6-T SRAM cell size of 0.69 /spl mu/m/sup 2/ with a 45 nm gate length is demonstrated. Electrical data of functional SRAM bit-cell is presented at V/sub dd/=0.9 Volt using a conventional nitrided gate oxide dielectric. A comparison between offset spacer and PLAsma Doping (PLAD) is made for the transistor characteristics with very promising V/sub th/-L/sub d/ and V/sub th/-W/sub d/ profiles measured. Lithography employed a combination of both optical lithography and e-beam imaging. The BEOL integration used a conventional low K dielectric with copper metallization.

A 65nm CMOS platform employing General Purpose (GP) and Low Power (LP) devices and 0.5 /spl mu/m/sup 2/ 6T-SRAM bit-cells was developed using both conventional design and low cost CMOS process flow incorporating a strained silicon solution. Fully working 0.5 /spl mu/m/sup 2/ bit-cells with 240mV of SNM and 35 /spl mu/A of cell current at 1.2V operation were obtained. The GP transistor drive currents of 875 /spl mu/A/ /spl mu/m and 400 /spl mu/A/ /spl mu/m for NMOS and PMOS respectively are obtained at V/sub dd/ = 1V, Ioff = 100nA/um. Using the same CMOS flow, 65nm analog transistor parameters are derived for the first time, showing Vt matching (Avt=2.2mV. /spl mu/m) and analog voltage gain factor (G/sub m//G/sub d/>2000 for L = 10 /spl mu/m) at the leading edge for this process technology. NBTI criteria at 125/spl deg/C for both LP and GP transistors are presented and characterized at overdrive conditions.

New fluorescent ligands for adenosine receptors (ARs), obtained by the insertion, in the N(6) position of NECA, of NBD-moieties with linear alkyl spacers of increasing length, proved to possess a high affinity and selectivity for the A(3) subtype expressed in CHO cells. In fluorescence microscopy assays, compound 2d, the most active and selective for human A(3)-AR, permitted visualization and localization of this human receptor subtype, showing its potential suitability for internalization and trafficking studies in living cells.

Strong evidence is emerging that mitochondrial permeability transition (MPT) may be important in certain physiological conditions and, above all, in the processes of cell damage and death. Reversible MPT, triggered by inducing agents in the presence of calcium ions, has resulted in the opening of a dynamic multiprotein complex formed in the inner mitochondrial membrane and has caused large-amplitude mitochondrial swelling. In the present work, the exposure of de-energized rat cardiac mitochondria to peripheral benzodiazepine receptor (PBR) ligands (1-(2-chlorophenyl-N-methyl-1-methylpropyl)-3-isoquinolinecarboxamide (PK 11195), 7-chloro-5-(4-chlorophenyl)-1,3-dihydro-1-methyl-2H-1,4-benzodiazepin-2-one (Ro5-4864), and diazepam) produced a dose-dependent and cyclosporin A (CSP)-sensitive loss of absorbance, which was indicative of mitochondrial swelling. By contrast, the addition of a high-affinity central benzodiazepine receptor ligand (clonazepam) was ineffective, even at the highest concentration tested. The ultrastructural changes associated with swelling were similar in mitochondria exposed either to PK 11195 or to calcium. Supporting the apoptotic role of PK 11195-induced swelling, supernatants from mitochondria that had undergone permeability transition caused apoptotic changes in isolated cardiac nuclei. In addition, ultrastructural abnormalities were observed in rat cardiac tissue following in vivo PK 11195 administration, with these abnormalities being prevented by CSP co-administration. These data indicate that PBR ligands induce mitochondrial permeability transition and ultrastructural alterations in isolated cardiac mitochondria as well as in myocardiocytes, suggesting a novel strategy for studying the implication of PBR ligands as apoptosis inducers, through a probable effect on the MPT pore.

Summary In this study we measured the ability of three newly-synthesized N-arylalkylindol-3-ylglyoxylylamide derivatives, which have recently been characterized as partial agonists at central benzodiazepine binding sites, to prevent the rat cardiac mitochondrial alterations resulting from acute loud noise exposure. In particular, we evaluated the effects of these new compounds on the ultrastructural damage induced by noise stress on the right atrium and ventricle after 6 and 12 hr of loud noise exposure. In parallel experiments, we measured the affinity of these compounds for peripheral benzodiazepine binding sites. Following a single injection of the test products, we observed a cardioprotective effect which was more marked after 6 hr compared with 12 hr of noise exposure. Confirming our recent data showing that full agonists at benzodiazepine receptors produce cardioprotection, we demonstrate in this study that partial agonists, like indolylglyoxylylamides, can also produce a cardioprotective effect. Based on their greater affinity in binding studies, the protective activity seems to be related more to their action at central than at peripheral benzodiazepine receptors.

Noise is an environmental physical agent, which is regarded as a stressful stimulus: impairment and modifications in biological functions are reported, after loud noise exposure, at several levels in human and animal organs and apparatuses, as well as in the endocrine, cardiovascular and nervous system. In the present study equilibrium binding parameters of peripheral benzodiazepine receptors (PBRs) labelled by the specific radioligand [3H]PK 11195, were evaluated in cardiac tissue of rats submitted to 6 or 12 h noise exposure and of rats treated "in vivo" with PBR ligands such as PK 11195, Ro54864, diazepam and then noise-exposed. Results revealed a statistically significant decrease in the maximum number of binding sites (Bmax) of [3H]PK 11195 in atrial membranes of 6 or 12 h noise exposed rats, compared with sham-exposed animals, without any change in the dissociation constant (Kd). The "in vivo" PBR ligand pre-treatment counteracted the noise-induced modifications of PBR density. As PBRs are mainly located on mitochondria we also investigated whether noise exposure can affect the [3H]PK 11195 binding parameters in isolated cardiac mitochondrial fractions. Results indicated a significant Bmax value decrease in right atrial mitochondrial fractions of rats 6 or 12 h noise-exposed. Furthermore, as PBR has been suggested to be a supramolecular complex that might coincide with the not-yet-established structure of the mitochondrial permeability transition (MPT)-pore, the status of the MPT-pore in isolated heart mitochondria was investigated in noise- and sham-exposed rats. The loss of absorbance associated with the calcium-induced MPT-pore opening was greater in mitochondria isolated from hearts of 6 h noise- than those of sham-exposed rats. In conclusion, these findings represent a further instance for PBR density decrease in response to a stressful stimulus, like noise; in addition they revealed that "in vivo" administration of PBR ligands significantly prevents this decrease. Finally, our data also suggest the involvement of MPT in the response of an organism to noise stress.

New fluorescent ligands for adenosine receptors are described; these compounds were obtained by the insertion, in the N 6 position of NECA (a potent adenosine agonist), of dansylaminoalkyl moieties with alkyl spacers of increasing carbon chain length (from 3 to 12). Among them, the compound with a C6 alkyl spacer proved to be the most interesting one, showing a marked selectivity for the A 1 receptor subtype; furthermore, in fluorescence microscopy assays it proved to be able to visualize and localize this receptor subtype at the level of the molecular layer of the rat cerebellar cortex.

Adenosine is an ubiquitous nucleoside that mediates several important physiological effects, trough the binding of three pharmacologically distinct receptor subtypes, named A1 A2 and A 3 .1 Adenosine receptor subtypes has been distinguished on the basis of the effect of adenosine on the cellular content of cAMP: occupancy of A2 adenosine receptors induces an increase in cAMP level in several cells types, by contrast stimulation of A 1 receptors causes the opposite effect. These effects are mediated by a coupling of these receptor subtypes with Gs and Gi transduction-proteins, respectively.2

Cross sections per equivalent quantum, in the energy range 0.3–1.0 GeV, have been measured for spallation residuals from 51V, 55Mn, natural Fe, and 59Co targets. Mean cross sections per photon have been deduced in this energy range and the data analysed in terms of charge-dispersion curves and mass-yield distributions. The mean cross sections per photon have also been compared with a semiempirical Rudstam's formula. A satisfactorily good agreement has been found with the calculated yields within a factor of two.

The Zeeman effect on the nuclear quadrupole resonance of both 35Cl and 14N nuclei in a single crystal of p‐chloroaniline has been studied at room temperature. A spectrometer was employed which was capable of working at the resonance frequency of either nucleus without altering the position of the crystal. Novel features of the spectrometer were both a frequency stabilizing apparatus working at the 14N resonance frequency and the attachment of an electronic computer for direct and accurate ``on‐line'' determination of spectral parameters. The relative orientations of the electric field gradient tensors on both nuclei have been obtained. Furthermore, by studying the 14N linewidth dependence on the static magnetic field orientation, information has also been gained about the position of the −NH2 protons in the electric field gradient tensor principal axes mainframe. Some remarkable experimental results can be interpreted theoretically when the treatment of the magnetic dipole interaction between 14N and 1H i...

The CO2-laser-induced decomposition of cyclohexene has been studied in the presence of SiF4, SF6 and C6F6 as sensitizers. The pressure range investigated is between 10 and 30 Torr at laser fluences between 0.20 and 1.20 J cm−2. At the same time measurements of the IR multiphoton absorption of the three sensitizers were also performed. The results have been analyzed within the framework of a kinetic model based on the assumption that the rate is controlled by vibrational energy transfer from the multiphoton-excited sensitizer molecules to the reactant. Evidence is presented to show that these sensitized reactions proceed under non-equilibrium conditions.

Mean cross sections for the photoproduction of 11C and 7Be from 40Ca targets have been measured using bremsstrahlung beams in the energy range 0·3–1 GeV. The values obtained turned out to be much larger than those expected from a simple spallation mechanism. A fragmentation-like process has therefore been suggested to explain such a discrepancy.

The use of the 19F(γ, n)18F, 27Al(γ, x)24Na, 197Au(γ, n)196Au, and 12C(γ, x)7Be reactions as absolute monitors for high-energy, high-intensity bremsstrahlung beams is discussed. The cross sections per equivalent quantum and the absolute cross sections, in the energy range 300–1000 MeV, are reported for these reactions. 19F(γ, n)18F, 27Al(γ, x)24Na, and 12C(γ, x)7Be reactions are proposed as very simple and suitable systems for monitoring purposes.

Aluminium targets have been irradiated with bremsstrahlung beams at energies between 0·3 GeV and 1GeV and the cross-sections of the photoproduction of 18 F have been measured by activation analysis.

In the energy range from 300 MeV up to 1000 MeV, cross-sections for the reactions12C(γ, n)11C and12C(γ, x)7Be have been measured using bremsstrahlung beams of the Frascati electronsynchrotron by means of the activation method. The (γ, n) cross-section measured, (1.18 ± 0.20) mb, is in agreement with the predicted from the photomeson model. The12C(γ, x)7Be cross-section found was (8±4) · 10−29 cm2.

The absolute cross-sections in the energy range (300÷1000) MeV for (γ, n), (γ, 2n) and (γ, 3n) reactions on127I are reported. Theσ K for these reactions are proportional respectively to 125, 29 and 1. That seems to be due to a frequent process in which the high-energy photon gives only a low-energy excitation to the nucleus.

The (γ, n) cross sections per equivalent quantum of 12C, 103Rh, 127I, 197Au and 238U have been measured with a bremsstrahlung beam of maximum energies in the range 1–5.5 GeV. Within the experimental errors of the activation method, no contribution of photons above 1 GeV was found. This result disagrees with some previous measurements at energies below 1 GeV but agrees with the predicted values obtained from simple theoretical estimates.

Polyethylene, water, lithium fluoride, aluminium, and sulfur targets have been irradiated with 1-GeV bremsstrahlung beams at the Frascati electron synchrotron and the yields of some spallation products from $^{27}\mathrm{Al}$ and $^{32}\mathrm{S}$ and of $^{11}\mathrm{C}$ and $^{7}\mathrm{Be}$ from $^{12}\mathrm{C}$, $^{16}\mathrm{O}$, $^{19}\mathrm{F}$, $^{27}\mathrm{Al}$, and $^{32}\mathrm{S}$ have been measured by the induced-activity and radiochemical methods. Evidence has been deduced for fragmentation from the mass-yield distribution of the photoproduced nuclides in $^{27}\mathrm{Al}$ and $^{32}\mathrm{S}$.

The use of the ferrous sulfate dosimeter in the energy range of 0.3–1 GeV is proposed. The linearity range of dosimeter and the comparison between its response and that of the Wilson quantameter are described. Approximate G values at 0.3 and 1 GeV have been determined.

On montre que des erreurs importantes peuvent être faites dans les mesures d'activité α naturelle par suite de la diffusion du Radon. Ces erreurs peuvent être évitées en mesurant l'activité de l'échantillon refroidi à - 180 °C, à l'aide d'un compteur à scintillation. © 1956 Società Italiana di Fisica., SCOPUS: ar.j, info:eu-repo/semantics/published

The separation of Tellerium 127 and 129 nuclear isomers by paper chromatography is described. The dibutyltelluride, formed from tellurite during isomer transition in a medium of HCl-butyl alcohol, travels with the solvent from whilst the tellurite shows a Rf = 0·60.