A bsttract. In contrast to intact etiolated pea seedling tissue (Pisum sativum L.), excised segments immersed in a complete nutrient solution show marked increases in ion content, largely of K+ and NO.-, over a 72-hour period. During this time there is increase in cell electropotential difference, PD. During the initial 6 to 8 hours there is a lag in ion uptake; cell PD, however, increases rapi...

*Correspondence: Nikolai Lebedev and Leonard M. Tender , 4555 Overlook Avenue, SW, Washington, DC, USA e-mail: [email protected]; [email protected] Atomic force microscopy and confocal resonance Raman microscopy (CRRM) of singlecells were used to study the transition of anode-grown Geobacter sulfurreducens biofilms from lag phase (initial period of low current) to exponenti...

Bacterial cells in the logarithmic phase of growth are characterized by an ability to reproduce in fresh media without the initial lag period required by organismns in later phases of development. It would seem that the latter lack certain chemical or physiological properties prerequisite to cell division. The type of changes taking place during what may be called the rejuvenation of the cell h...

Considering coupled phase model oscillator systems with non-identical time delays, we study the possibility of close-to-zero phaselag synchronization (ZPS) without frequency depression (FD). FD refers to nearly vanishing frequencies of the synchronized oscillators (in comparison to the intrinsic frequencies); its absence is crucial for interpretations related to brain dynamics. Discussing an ex...

Abstract: In this note we consider two cases in the theory of the heat conduction models with three-phase-lag. For each one we propose a suitable Lyapunov function. These functions are relevant tools which allow to study several qualitative properties. We obtain conditions on the material parameters to guarantee the exponential stability of solutions. The spectral analysis complements the resul...

The use of frequency-weighted performance indices in linear quadratic (LQ) optimal control has been the subject of recent r e ~ e a c h ' ~ . The primary motivation for frequency-weighting is the possibility of enhancing the robustness of LQ designs in critical frequency bands. A preliminary study3 of the case where high frequencies in the control are weighted more heavily has shown that the op...

1. When chick-embryo cells were treated with ultraviolet-inactivated influenza virus (Melbourne strain), interferon was produced after a lag period of about 10hr. 2. The addition of small amounts of either puromycin or p-fluorophenylalanine immediately after the virus inhibited the subsequent production of interferon. Both inhibitors primarily affected protein synthesis, and it is concluded tha...

The objective of this work was to explore the large number of bacterial growth models recently proposed in the field of predictive microbiology, concerning their capacity to give reliable estimates of the lag phase duration (lambda). We compared these models on the basis of their underlying biological explanations of the lag phenomenon, their mathematical formulation and their statistical fitti...