ARCHEAN CHERTS: CAN ELECTRON PARAMAGNETIC RESONANCE PROVIDE CLUES? A. Skrzypczak, L. Binet, D. Gourier, S. Derenne and F. Robert. Ecole Nationale Supérieure de Chimie de Paris, 11 rue Pierre et Marie Curie, F-75231 Paris cedex 05, France ([email protected], [email protected], [email protected], [email protected]), Museum National d'Histoire Naturelle, La...

in this paper, a three dimensional mathematical model for htlv-1infection with intracellular delay and immune activation delay is investigated.by applying the frequency domain approach, we show that time delays candestabilize the ham/tsp equilibrium, leading to hopf bifurcations and sta-ble or unstable periodic oscillations. at the end, numerical simulations areillustrated.

In Escherichia coli, a relatively low frequency of recombination exchanges (FRE) is predetermined by the activity of RecA protein, as modulated by a complex regulatory program involving both autoregulation and other factors. The RecA protein of Pseudomonas aeruginosa (RecA(Pa)) exhibits a more robust recombinase activity than its E. coli counterpart (RecA(Ec)). Low-level expression of RecA(Pa) ...

OBJECTIVE Otologic surgery is undertaken to treat ailments of the ear, including persistent infections, hearing loss, vertigo, and cancer. Typically performed on otherwise-healthy patients in outpatient facilities, the application of image-guided surgery (IGS) has been limited because accurate (<1 mm), non-invasive fiducial systems for otologic surgery have not been available. We now present su...

Cultured hepatocytes from adult Fischer 344 rats were transformed by virion or cloned simian virus 40 (SV40) DNA using the calcium phosphate method. Transformation by SV40 occurred in either serumsupplemented medium or chemically defined medium (COM). The fre quency was greatest in serum-supplemented medium but transformants did not remain differentiated. In contrast, SV40 transformants develop...

Cultured hepatocytes from adult Fischer 344 rats were transformed by virion or cloned simian virus 40 (SV40) DNA using the calcium phosphate method. Transformation by SV40 occurred in either serumsupplemented medium or chemically defined medium (COM). The fre quency was greatest in serum-supplemented medium but transformants did not remain differentiated. In contrast, SV40 transformants develop...

MICROWAVE signal sources of high fre quency-stability and spectral purity are increasingly important to many fields. These include doppler systems, nuclear spectroscopy measurements, spectrum analyzers, as well as telemetry, radio astronomy, and other com munications-type work. All of these applica tions are characterized by the need for good shortand long-term stability as well as low residual...

Brain waves are proposed as a biometric for verification of the identities of individuals in a small group. The approach is based on a novel two-stage biometric authentication method that minimizes both false accept error (FAE) and false reject error (FRE). These brain waves (or electroencephalogram (EEG) signals) are recorded while the user performs either one or several thought activities. As...