Publisher Correction: Shedding new light on the Crab with polarized X-rays.

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Shedding new light on the Crab with polarized X-rays.

Strong magnetic fields, synchrotron emission, and Compton scattering are omnipresent in compact celestial X-ray sources. Emissions in the X-ray energy band are consequently expected to be linearly polarized. X-ray polarimetry provides a unique diagnostic to study the location and fundamental mechanisms behind emission processes. The polarization of emissions from a bright celestial X-ray source, the Crab, is reported here for the first time in the hard X-ray band (~20-160 keV). The Crab is a complex system consisting of a central pulsar, a diffuse pulsar wind nebula, as well as structures in the inner nebula including a jet and torus. Measurements are made by a purpose-built and calibrated polarimeter, PoGO+. The polarization vector is found to be aligned with the spin axis of the pulsar for a polarization fraction, PF = (20.9 ± 5.0)%. This is higher than that of the optical diffuse nebula, implying a more compact emission site, though not as compact as, e.g., the synchrotron knot. Contrary to measurements at higher energies, no significant temporal evolution of phase-integrated polarisation parameters is observed. The polarization parameters for the pulsar itself are measured for the first time in the X-ray energy band and are consistent with observations at optical wavelengths.

[The Buccal Epithelium as Environmental Indicator].

The use of the buccal mucosa cell micronucleus test for comparison of chemical, radiation, and radiation-chemical environmental pollution has been considered. The combined impact of chemical and radiation factors has been found to cause additive effects, synergism, and inhibition. It has been noted that the cytogenetic characteristics of the buccal epithelium may be used as a "biological dosimeter" of the total level of environmental pollution.

[Effect of radioactive, toxic, and combined radiation and toxic pollution of the environment on the incidence of malignant neoplasms in children of the Briansk region].

Comparative evaluation of the frequency of incidence of all forms of primary malignant tumors in the child population over the fourteen-year period (1995-2008.) is presented. Evaluation was carried out in ecologically unfavorable territories of the Bryansk region with varying density of radioactive (from 28.1 to 661.9 kBq/m2 for 137Cs), toxic (from 1.47 to 183.6 kg/person/year for gaseous toxic substances) and combined environment pollution. Statistically significant differences of incidence of malignant neoplasms in children in ecologically unfavorable areas have been established.

Technetium(I) carbonyl dithiocarbamates and xanthates.

Technetium(I) tetracarbonyl complexes with diethyldithiocarbamate and methylxanthate ligands [TcL(CO)(4)] (L = S(2)CNEt(2) and S(2)COMe) were prepared. Conditions required for the formation of these complexes were found. The crystal and molecular structure of the xanthate complex was determined by single-crystal X-ray diffraction. [Tc(S(2)CNEt(2))(CO)(4)] undergoes decarbonylation both in solution and in the course of vacuum sublimation with the formation of a dimer [Tc(S(2)CNEt(2))(CO)(3)](2) whose structure was determined by single-crystal X-ray diffraction. In donor solvents, [Tc(S(2)CNEt(2))(CO)(4)] and [Tc(S(2)COMe)(CO)(4)] undergo decarbonylation with the formation of tricarbonyl solvates [TcL(CO)(3)(Sol)]. The crystal structure of the pyridine solvate [Tc(S(2)CNEt(2))(CO)(3)(py)], chosen as an example, was determined by single-crystal X-ray diffraction. The possibility of using bidentate S-donor acidic ligands for tethering the tetracarbonyltechnetium fragment to biomolecules was examined.