Analysis of gate-bias-induced heating effects in deep-submicron ESD protection designs

This paper presents a detailed investigation of the degradation of electrostatic discharge (ESD) strength with high gate bias for deep-submicron salicided ESD protection nMOS transistors, which has significant implications for protection designs where high gate coupling occurs under ESD stress. It has been shown that gate-bias-induced heating is the primary cause of early ESD failure and that this impact of gate bias depends on the finger width of the protection devices. In addition, it has been established that substrate biasing can effectively alleviate the adverse impact of the gate bias and can improve ESD strength despite the gate-coupling level. Improved understanding of ESD behavior for advanced devices under high gate-coupling conditions can extend design capabilities of protection structures.     

Children''s understanding of extended identity

OBJECTIVE: To compare the properties of single myocytes isolated from different layers of the basal region of the left ventricle and to test the hypothesis that differences in the delayed rectifier current (IK) contribute to regional differences in action potential duration. METHODS: Myocytes were isolated from basal sub-endocardial, mid-myocardial and sub-epicardial layers of the guinea-pig left ventricle. Membrane voltage and current were measured using the switch-clamp technique. RESULTS: Mean action potential duration measured at 90% repolarisation (APD90) was longer in sub-endocardial myocytes than in mid-myocardial and sub-epicardial myocytes [APD90 ms at 0.2 Hz: sub-endocardial 292 +/- 12 (n = 40), mid-myocardial 243 +/- 8 (n = 42) and sub-epicardial 227 +/- 9 (n = 36), P < 0.001, analysis of variance (ANOVA)]. The APD-rate relationship (stimulation frequencies 2, 1, 0.2 and 0.017 Hz) was steeper in sub-endocardial than in mid-myocardial or sub-epicardial myocytes (P < 0.001, ANOVA). The density of IK was greater in mid-myocardial (4.05 +/- 0.09 pA pF-1) and sub-epicardial (3.90 +/- 0.41 pA pF-1) than in sub-endocardial myocytes (2.74 +/- 0.27 pA pF-1, P < 0.01 ANOVA). The rapidly-activating (IKr) and slowly-activating (IKs) components of IK were significantly smaller in sub-endocardial than in mid-myocardial or sub-epicardial myocytes. D,L-Sotalol-induced prolongation of APD90 was similar in the three regions studied. CONCLUSIONS: There are significant transmural gradients in the electrophysiological properties of myocytes isolated from the base of the left ventricular free wall in guinea-pig. Sub-endocardial myocytes had a longer APD90 attributable in part to a significantly smaller IK density. We have been unable to identify M cells in the guinea-pig left ventricular free wall.     

Homogeneous reduction of aromatic nitrocompounds by a triphenylphosphine complex of palladium

The complex Pd₂(PPh₃)₂Cl₄ has been used as a homogeneous catalyst for the reduction of C₆H₅NO₂ and p-ClC₆H₄NO₂ in basic ethanol. A reaction intermediate [Pd(PPh₃) (C₆H₅NO₂)Cl₂] has been isolated and characterised. Reduction of C₆H₅NO₂ produced aniline (75%), azobenzene (5%) and azoxybenzene (15%) under conditions of atmospheric pressure, while under conditions of high pressure the reduction product contained aniline (95%) only. The yield of p-ClC₆H₄NH₂ was highest (75%) at normal pressure and decreased with increasing pressure.     

Studies on glass-reinforced epoxy resin using either Vulkadur A or a mixture of Vulkadur A and triethanolamine as crosslinking agent

Epoxy resin can be reinforced with glass (fabric form) using Vulkadur A (a phenol formaldehyde resin containing an hardening agent) as a crosslinking agent. Overall enhancement in mechanical properties has been observed with stocks cured with a mixture of Vulkadur A and triethanolamine.     

Aesthetics of navigational performance in hypertext

A hypertext learner navigates with a instinctive feeling for a knowledge. The learner does not know her queries, although she has a feeling for them. A learners navigation appears as complete upon the emergence of an aesthetic pleasure, called rasa. The order of arrival or the associational logic and even the temporal order are not relevant to this emergence. The completeness of aesthetics is important. The learner does not look for the intention of the writer, neither does she look for significance. Lexia has a suggestive power and she is suggested in the arrival of aesthetics. Hypertext learning does not depend on communication. The learner in her pleasure transgresses the bounds of space-time to be in communion with several writers/learners. Hypertext learning does not appear to be fundamentally different from the analog learning; however, in performance, as in navigation, the learner assumes a mental state that helps her in her emergence into aesthetic bliss, of an arrival to the completed lexial navigation. This completeness is owing to aesthetics and is not owing to either the semantics or the query-fulfilling qualities.     

Formation of a DO19 phase in zirconiumaluminium martensites

Journal of Materials Science -     

On the phase-space dynamics of systems of spiking neurons. I: model and experiments

We investigate the phase-space dynamics of a general model of local systems of biological neurons in order to deduce the salient dynamical characteristics of such systems. In this article, we present a detailed exposition of an abstract dynamical system that models systems of biological neurons. The abstract system is based on a limited set of realistic assumptions and thus accommodates a wide range of neuronal models. Simulation results are presented for several instantiations of the abstract system, each modeling a typical neocortical column to a different degree of accuracy. The results demonstrate that the dynamics of the systems are generally consistent with that observed in neurophysiological experiments. They reveal that the qualitative behavior of the class of systems can be classified into three distinct categories: quiescence, intense periodic activity resembling a state of seizure, and sustained chaos over the range of intrinsic activity typically associated with normal operational conditions in the neocortex. We discuss basic ramifications of this result with regard to the computational nature of neocortical neuronal systems.