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and selective sensing of L -cysteine. Talanta 2009,77(5):1654–1659.CrossRef 33. Chen H, Gao F, He R, Cui D: Chemiluminescence of luminol catalyzed by silver nanoparticles. J selleck chemical Colloid Interface Sci 2007, 315:158–163.CrossRef PLX4032 in vitro Competing interests The authors declare that they have no competing interests. Authors’ contributions BL, JB, and HD carried out the experimental work, participated in the planning of the experiment and drafted the manuscript. ZP and LD participated

in the argument on this manuscript and the manuscript was touched up by them. All authors read selleck chemicals and approved the final manuscript.”
“Background The collective absorption (emission) of photons by an ensemble of identical atoms ‘provides valuable insights into the many-body physics of photons and atoms’ (quoted from [1]). Taking into account the

quantization of electromagnetic field, many fundamental and interesting properties of the coupled systems of atoms and field are revealed. For example, when the average distances between atoms are much less than the ‘resonant transition’ wavelength of emitted (absorbed) light, the cooperative coupling leads to a substantial radiative shift of the transition energy and significant change in decay rate of the ensemble state. The latter was revealed through the various Thymidylate synthase theoretical (for example, some relatively modern researches in [2–5]) and experimental investigations (see starting, for example, from [6, 7] to the modern applications like described in [8] and impressively effective experimental realizations as in [1]). Some peculiar behavior in spontaneous emission is proper even in a system of atoms which can have a relative distance larger than the emission wavelength (see, for instance, [9]), and initially, only one atom or one-photon state is excited, as discovered in this paper. In the present paper, a system (chain) of N identical two-level non-interacting atoms, prepared ‘via a single-photon Fock state’ in the one- or two-mode resonator, is investigated. The main goal of the paper is to obtain the information about the state of electromagnetic field and atomic system (chain) in a Weisskopf-Wigner approximation (see [10] chapter 6, page 206 and some comments in [11]).