Multipolar model of bremsstrahlung accompanying proton-decay of nuclei

Emission of bremsstrahlung photons accompanying proton decay of nuclei is studied. The new improved multipolar model describing such a process is presented. The angular formalism of calculations of the matrix elements is stated in details. The bremsstrahlung probabilities for the $^{157}{\rm Ta}$, $^{161}{\rm Re}$, $^{167}{\rm Ir}$ and $^{185}{\rm Bi}$ nuclei decaying from the $2s_{1/2}$ state, the $^{109}_{53}{\rm I}_{56}$ and $^{112}_{55}{\rm Cs}_{57}$ nuclei decaying from the $1d_{5/2}$ state, the $^{146}_{69}{\rm Tm}_{77}$ and $^{151}_{71}{\rm Lu}_{80}$ nuclei decaying from the $0h_{11/2}$ state are predicted. Such spectra have orders of values similar to the experimental data for the bremsstrahlung photons emitted during the $\alpha$-decay. This indicates on real possibility to study bremsstrahlung photons during proton decay experimentally and perform further measurements.Comment: 14 pages, 6 figure

Cooperation between Russian research organizations and industrial companies: factors and problems

The study is focused on the cooperation of Russian companies with research organizations in implementing R&D projects during technological innovation. Taking into account behavioral changes, authors carry out a micro-level analysis based on empirical data of executive survey of over 600 Russian industrial firms (2011—2012) and about 350 research organizations and universities (2012). The authors emphasize the key factors of firms’ demand for outsourcing R&D reveal the main barriers to the development of university-industry cooperation and their particularities for different cooperation actors. The analysis shows that there is a positive relation between the size of a company and R&D outsourcing. As for the factor of age, the highest cooperation activity of Russian firms is observed among enterprises founded over 20 years ago. As far as concernes cooperation activity of research organizations, large ones are significantly more likely to cooperate with business. A common prerequisite for research organizations' R&D cooperation with business is sufficient academic ranking. Business and science evaluate differently various obstacles to effective cooperation. For firms, the main problems are the inflated costs of national R&Ds, insufficient research organizations’ orientation at company needs, and low quality of developments. As for representatives of research organizations, they mention as barriers primarily the lack of companies' receptivity to innovation and inadequate information about promising developments. Businesses are more optimistic about cooperation with science if they already have a relevant experience of interaction. In the case of research organizations we observe a different pattern: most problems seem more significant to organizations conducting R&D in business interests

Functions of metallothioneins and a system of antioxidant defense under the effect of Co- and Zn-containing nanocomposites on crucian carp (Carassius auratus gibelio)

The effect of metal-nanocomposites (Me-NC) of cobalt and zinc (Co- and Zn-NC, correspondingly) synthecized on the basis of vinylpyrrolidone (PS) on the metal-accumulative proteins with antioxidant potential metallothioneins (MT) in crucian carp (Carassius auratus gibelio) was studied­. Fish was subjected to the effect of Co-NC, Zn-NC, Co2+, Zn2+ or polymer carrier (PC) in the concentrations correspondent to 50 µg×Co/l or 100 µg×Zn/l during 14 days. It was shown that the MTs response is highly specific for the nature of metal, both in ion and Me-NC form: the effect of Co and Co-NC provoked the elevation of total MT concentration (MT-SH) and activation of antioxidant defence, whereas Zn and Zn-NC induced the decrease of the concentration of MT-SH and the inhibition of antioxidant defense. All the exposures provoked the decrease of the concentration of immunoreactive chelating MT form (MTi) and reduced glutathione, activation of anaerobiosys and Mn-superoxide dismutase, and also decrease of the concentration of proteins and lipids oxidative injury products. It was accompanied by the increase of the content of erythrocytes with nuclear abnormalities but did not cause the decrease of choline esterase activity. According to the rate of MT-SH and MTi concentrations, antioxidant potential of MTs is determined by its apoform. Our data indicate that partial biodegradation of Me-NC occurs in the organism of crucian carp

Determination of Magnetic Parameters of Maghemite (γ-Fe2O3) Core-Shell Nanoparticles from Nonlinear Magnetic Susceptibility Measurements

Abstract Method of determining of magnetic moment and size from measurements of dependence of the nonlinear magnetic susceptibility upon magnetic field is proposed, substantiated and tested for superparamagnetic nanoparticles (SPNP) of the “magnetic core-polymer shell” type which are widely used in biomedical technologies. The model of the induction response of the SPNP ensemble on the combined action of the magnetic harmonic excitation field and permanent bias field is built, and the analysis of possible ways to determine the magnetic moment and size of the nanoparticles as well as the parameters of the distribution of these variables is performed. Experimental verification of the proposed method was implemented on samples of SPNP with maghemite core in dry form as well as in colloidal systems. The results have been compared with the data obtained by other methods. Advantages of the proposed method are analyzed and discussed, particularly in terms of its suitability for routine express testing of SPNP for biomedical technology

Morphology of the Micelles Formed by a Comb-Like PEG-Containing Copolymer Loaded with Antitumor Substances with Different Water Solubilities

The controlled delivery of anticancer drugs is driven by their interaction with carrier molecules. By creating complicated micelle-like complexes, amphiphilic polymers provide an opportunity to load drugs of various kinds. In this work, the interaction of the comb-like PEG-containing polymer poly(VEP-co-GMA)-graft-PEG with the water-soluble antitumor antibiotic doxorubicin and new water-insoluble derivatives of thiozalidinone Les-3883 characterized by a high anticancer efficiency has been studied in aqueous solutions by means of the SAXS, DLS, TEM, and photoluminescence methods. The formation of polymer micelles and their complexes with drugs, as well as their structural changes, is observed. The obtained results give evidence that the mechanism of organization of supramolecular complexes depends on the drug solubility in water. A potential capability of poly(VEP-co-GMA)-graft-PEG to prolong the drug circulation lifetime is confirmed