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From 1998 to 2000, 184 animals (82 wolves, 29 red foxes, 55 mustelids, 5 raccoon dogs, and 13 domestic dogs), mainly shot by hunters in the Tvier and Smoliensk regions of northwest European Russia, were tested for Trichinella larvae; 98 animals (53.3%) were found to be positive. The highest prevalence was detected in wolf (97.5%). Trichinella nativa was the most common species detected (98%). The diet of wolves was investigated by examining the stomach contents of 62 animals (75.6% of the total number of wolves examined for Trichinella). It consisted mainly of dog (36.4% of the total number of occurrences of all food items, PFO) and moose (31.2 PFO); however, during the hunting seasons of 1998-1999 and 1999-2000, skinned wolf carcasses were left in the forest as bait (567 carcasses, about 18,000 kg). This very high prevalence of Trichinella infection, the highest ever detected in a natural population of carnivores, could be explained by carnivore-carnivore transmission, influenced by the hunting practices adopted in the study area.

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As negative-MOSFET (NMOSFET) size and voltage are scaled down, the electron-energy distribution becomes increasingly dependent only on the applied bias, because of quasi-ballistic transport over the high-field region. A new paradigm, or underlying concept, of NMOSFET hot-carrier behavior is proposed here, in which the fundamental "driving force" is available energy, rather than peak lateral electric field, as it is in the lucky electron model (LEM). The new prediction of the energy-driven paradigm is that the bias dependence of the impact-ionization (II) rate and hot-carrier lifetime is, to the first order, given by the energy dependences of the II scattering rate S II (E) and an effective interface state generation (ISG) cross section S IT (E), whereas, under the LEM, these bias dependences are determined by the number of electrons with energy above the II and ISG "threshold energies." This approach allows an experimental determination of S IT .

This work investigates the impact of Negative Bias Temperature Instability (NBTI) on the SRAM cell stability. As proposed by C. Wang et al. [1], the stability of an SRAM cell can be determined by the peak current (I CRIT ) of the "N Curve". In our experiments a typical NBTI stress was applied to one of the two pull up transistors part of an SRAM cell designed by using an advanced submicron CMOS technology. Both the mean and variance of the pMOSFET threshold voltage shift in saturation (ΔVt SAT ) and the corresponding values of the I CRIT shifts (ΔI CRIT ) were measured. An experimental correlation between the means and the variances of both parameters shifts was established and found consistent with the predicted simulated values in the case of I CRIT is degrading by only NBTI aging of the one or both pull up transistors. These results allow us to observe the direct impact of the NBTI shift of a pMOSFET transistor in a SRAM cell and the corresponding reduction to the Static Noise Margin. In addition we propose, for the first time, a methodology to define a pMOSFET device NBTI target directly related to the SRAM cell stability and its dependence on SRAM design and the adopted CMOS technology. It is found that a more appropriate SRAM stability sensitive pMOSFET NBTI Vt SAT target cannot be limited to the Vt SAT mean shift, but needs as well a quantification of the allowed variance and initial SRAM I CRIT distribution.