Unruh--DeWitt detectors in spherically symmetric dynamical space-times

In the present paper, Unruh--DeWitt detectors are used in order to investigate the issue of temperature associated with a spherically symmetric dynamical space-times. Firstly, we review the semi-classical tunneling method, then we introduce the Unruh--DeWitt detector approach. We show that for the generic static black hole case and the FRW de Sitter case, making use of peculiar Kodama trajectories, semiclassical and quantum field theoretic techniques give the same standard and well known thermal interpretation, with an associated temperature, corrected by appropriate Tolman factors. For a FRW space-time interpolating de Sitter space with the Einstein--de Sitter universe (that is a more realistic situation in the frame of $\Lambda$CDM cosmologies), we show that the detector response splits into a de Sitter contribution plus a fluctuating term containing no trace of Boltzmann-like factors, but rather describing the way thermal equilibrium is reached in the late time limit. As a consequence, and unlike the case of black holes, the identification of the dynamical surface gravity of a cosmological trapping horizon as an effective temperature parameter seems lost, at least for our co-moving simplified detectors. The possibility remains that a detector performing a proper motion along a Kodama trajectory may register something more, in which case the horizon surface gravity would be associated more likely to vacuum correlations than to particle creation.Comment: 19 pages, to appear on IJTP. arXiv admin note: substantial text overlap with arXiv:1101.525

Different reaction of core histones H2A and H2B to the red laser radiation

Aim: to investigate the influence of red laser irradiation on the processes of self-assembly of core histones H2A and H2B. Material and Methods. Solutions of human histone proteins were used in the work. Self-assembly was studied by the method of wedge dehydration. Image facies analysis consisted in their qualitative characterization and calculation of quantitative indicators with subsequent statistical processing. Results. It was established that linearly polarized laser light of the red region of the spectrum (A=660 nm, 1 J/cm2) significantly modifies the process of self-assembly of core histone H2B, while the structure of the facies of H2A histone changing to a lesser extent. Conclusion. Red laser radiation influences on the on the processes of self-assembly of core histones H2A and H2B. There is a differential sensitivity of different classes of histones to laser action. Histone proteins used in the experiments are present in the form of aqueous salt solutions. Red light realizes the effect seems to be due to the formation of singlet oxygen by direct laser excitation of molecular oxygen.</p

In-vitro and in-vivo characterization of ruthenium-bleomycin compared to cobalt- and copper-bleomycin

Bleomycin (BLM) has undergone extensive investigation both as a cancer chemotherapeutic agent, and as a carrier for radionuclides for tumor imaging. The available methods or the radionuclides used, however, have had limited effectiveness. Although labeling of BLM with /sup 103/Ru has been reported earlier, we carried out a study to develop a more reproducible method of labeling particularly for use with Brookhaven Linac Isotope Producer produced /sup 97/Ru. Ruthenium-97 has favorable physical properties that make it ideal for imaging applications: decay by electron capture; ..gamma.. 216 keV, 85%; t/sub 1/2/ 2.9 d. A novel method based on the reduction of Ru/sup 3 +/ to Ru/sup 2 +/ using stannous chloride was investigated for labeling BLM with /sup 97/Ru and/or /sup 103/Ru. In-vitro and in vivo comparisons of the product(s) with /sup 57/Co and /sup 67/Cu-labeled BLM were also carried out. 4 refs., 3 tabs