A framework for understanding the global structure of near-integrable n DOF Hamiltonian systems is proposed. To this aim two tools are developed—the energy-momentum bifurcation diagrams and the branched surfaces. Their use is demonstrated on a few near-integrable 3 DOF systems. For these systems possible sources of instabilities are identified in the diagrams, and the corresponding energy surfa...

The principle of "fluorescence resonance energy transfer" (FRET) has been exploited in cell biology to demonstrate the interaction of two proteins in living cells. FRET is highly specific and sensitive and allows for the online recording of events that modulate the interaction. We here demonstrate that FRET-based sensor molecules represent an alternative in monitoring receptor-dependent signall...

We demonstrate that energy can be transferred very rapidly from the bulk to the brane through parametric resonance. In a simple realization, we consider a massless bulk field that interacts only with fields localized on the brane. We assume an initial field configuration that has the form of a wave-packet moving towards the brane. During the reflection of the wave-packet by the brane the locali...

Current methods for fluorescence resonance energy transfer (FRET) microscopy of living cells involve taking a series of images with alternating excitation colors in separate camera exposures. Here we present a new FRET method based on polarization that requires only one camera exposure and thereby offers the possibility for better time resolution of dynamic associations among subcellular compon...

Förster, or fluorescence, resonance energy transfer (FRET) provides fluorescence signals sensitive to intra- and inter-molecular distances in the 1 to 10 nm range. Widely applied in the fluorescence imaging environment, FRET enables visualization of physicochemical processes in molecular interactions and conformations. In this paper, we report photoacoustic imaging of FRET, based on nonradiativ...

The idea to use the environmental energy to power electronic portable devices is becoming very popular in the last years. In fact, the possibility to do not depend only on the batteries can give to the devices longer operating periods in a fully sustainable way. Vibrational kinetic energy is a reliable and widespread environmental energy, that makes it a suitable energy source to exploit. In th...

It is shown that Förster's expression for the electronic energy transfer rate can be recast in a form predicted for exciton motion that interacts strongly with molecular vibrations. Using a simple model based on the Kennard-Stepanov theory, Förster's expression for the spectral overlap is shown to be of a thermally activated form, as obtained previously by multiphonon theory. In contrast, the h...

The existence of a structure in a resonance state is systematically investigated. A resonance structure is defined as the energy dependence across the resonance width of the fragment state distributions produced upon resonance decay. Different types of resonances, both isolated and overlapping ones, have been explored for this purpose. It is found that isolated resonances do not present an appr...

The FRET has been widely used as a spectroscopic technique in all applications of fluorescence including medical diagnostics, DNA analysis, optical imaging [1] and for various sensing properties [2-11]. Generally, fluorescence-based sensors adopt three different strategies: (a) fluorescence quenching (turn-off), (b) fluorescence enhancement (turn-on) and (c) ratiometric FRET. FRET sensors becam...

Topological resonance energy method, derived as a variant of Dewar resonance energy concept, and expressed by adjacency algebra formalism, has been for years applied for successful prediction of aromatic properties of conjugated organic and inorganic species. In this work a numerical value of TRE has been discussed in light of its physical meaning. Normalization method of this value has been pr...