A fully quantum treatment of the laser induced collisional energy transfer (LICET) processes, , where n = 3,4, is presented, which allows for non-adiabatic mixing between molecular states during the collision. LICET profiles have been calculated for both Lennard-Jones 12 - 6 and model adiabatic molecular potentials. The weak field LICET profiles obtained differ from those of conventional mixed metal vapour systems in that they are very broad, significantly shifted from zero detuning and exhibit novel complex resonant structure in the quasistatic wing. The profiles are very sensitive to the nature of the molecular potential at internuclear separations of less than and consequently differ greatly for the two sets of potentials used.

Bicoherence analysis is applied to electromyogram (EMG) data for the vastus lateralis quadriceps muscle of 18 adult male subjects for isometric knee extension exercise. Bicoherence spectra display ridge-like features that are indicative of deterministic chaotic behaviour and similar to those reported for normal electrocardiogram and electroencephalogram bicoherence spectra. No other obvious features are visually identified within bicoherence spectra in response to the stimulus of isometric tension. Histograms that show the occurrence of constituent EMG frequencies associated with the strongest bicoherence display subtle fluctuations. Validation tests that include the analysis of white noise data show these fluctuations to most likely be a consequence of the normal time evolution of a deterministic chaotic process. The finding suggests that second-order phase coupling is not pronounced between any particular bands of constituent EMG frequencies for the vastus lateralis EMG generation process during the specified isometric task. Previous studies into bicoherence analysis of EMG data are not apparent in the literature for comparison. Since nonlinear processes are known, through mechanomyogram bicoherence analysis, to be significant within active muscle fibre twitch summation patterns, the finding does not exclude the potential for bicoherence analysis to complement standard EMG frequency analysis techniques in the area of sports rehabilitation and medicine. Further investigation is required to establish whether this potential exists. An introduction to bicoherence analysis theory is also presented.

This paper presents a simple digital signal modulation/demodulation technique for the purpose of radiofrequency (RF) communications that involves the control of smooth phase amplitude oscillations within a carrier signal. The technique falls under the category of phase-shift keying (PSK) yet is distinctly different from existing PSK techniques. Identification of digital states is achieved via discernment between discrete combinations of off-centre side-lobes about the primary line profile of the carrier spectrum (ala discrete oscillator phase noise), with side-lobes being a function of the above phase amplitude oscillation. For a 2.4 GHz carrier signal, technique variants theoretically allow for competitive data transmission rates of 3 to 8 Mbit/s, which are extendable with variant expansion.Technique robustness (in relation to cryptographic security and resilience towards interference and distortion) is a consequence of amplitude fluctuation immunity, self-referencing at demodulation, smooth waveform transitions between states, single RF source control, and highly distinguishable output states for modest changes in the relevant phase-based modulation parameter.

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Bicoherence analysis is applied to electromyogram (EMG) data for vastus medialis obliques (VM), rectus femoris (RF) and vastus lateralis (VL) quadriceps muscles of 18 adult male subjects for isometric knee extension exercise. Mean average bicoherence for VM, RF and VL is 30.9 +/- 5.8, 26.0 +/- 1.2 and 25.4 +/- 1.4% respectively and repeated measures ANOVA differentiates the muscles on the basis of average bicoherence (F = 16.2 (1, 17), p = 0.0009, VM cf. VL and F = 15.4 (1, 17), p = 0.0011, VM cf. RF). Prominent regions representative of strong second-order phase coupling between constituent EMG frequencies are identified within VM and RF bicoherence spectra. No such prominent regions are identified for VL which is thought to be less activated than VM during the specified task. Hence, the degree of second-order phase coupling may increase as the level of muscle activation increases. The subject group consists of young (24.0 +/- 0.9 years) and elderly (68.9 +/- 0.9 years) subgroups that cannot be differentiated by standard indices (median and spectral edge frequency) to within p < 0.05 using the Mann-Whitney test. Average bicoherence differentiates the subgroups for RF (T = 9 (8,10), p < 0.005) but not for VM or VL. The application of a bicoherence threshold that takes harmonic amplitude into account graphically differentiates the subgroups for all muscle types. The findings suggest that nonlinear processes play a role within the EMG generation process and support a mechanomyogram bicoherence analysis study that shows nonlinear processes occur within active muscle fibre twitch summation patterns. A potential exists for bicoherence analysis to complement standard EMG frequency analysis techniques.