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The aim of this study was to evaluate the possible protective effect of preparation which synthesized in Vitebsk State Academy of Veterinary Medicine adsorbent (Toxicom) 5g\kg diet against the toxic effects of mixed mycotoxins in growing broiler chickens. Total 75 chicks, one week age, were divided into 5 treated groups,15 birds for each. The first group (G1) fed a contaminated ration with mycotoxin and supplemented with toxicom 5g/kg of diet and vaccinated with gumboro vaccine at 15 and 22 days of age. The second group (G2) was fed a ration contaminated with mycotoxin and vaccinated with gumboro vaccine at 15 and 22 days of age and not supplemented with toxicom. The third group (G3) was fed intact broiler ration and vaccinated with gumboro vaccine at 15 and 22 days of age. The fourth group (G4) was only fed a contaminated ration with mycotoxins. The fifth group (G5) was fed intact broiler ration as a control group. The diet was naturally contaminated with many mycotoxins and analyzed by ELISA and the level of mycotoxins were as follows : Aflatoxin B1 0.001 mg/kg, Dezoxivalenol 1.24 mg/kg, Zearalenon 0.068 mg/kg, Ochratoxin 0.005 mg/kg, T2 toxin 0.09 mg/kg, Fuminisen B1 0.2 mg/kg. The antibody titers for Infectious Bursal Disease vaccine (IBDv) was conducted by ELISA. It was concluded that this preparation which synthesized in Vitebsk State Academy of Veterinary Medicine is protect chickens body weight and decrease the effect of mycotoxins in comparison with the other groups and recommended for using as adsorbent in Republic of Belarus.

With the development of world economy gradual replacing of traditional organizational structures by organizational networks, take place. New organizational complexes set difficult tasks for researchers considering optimum building and functioning of organizational networks. In these conditions, a key focus of organization network research is simulating the interaction process as well as network’s integrated quantitative assessment based on this simulation. A distinctive feature of the applied simulating approach is formalization of interaction processes between the integrator and network entities taking into account their contradictory interests. The integrated quantitative assessment of a network is offered proceeding from understanding that the general purpose of functioning is satisfying society needs with products and services of a network.

Electron paramagnetic resonance (EPR) spectroscopy is used for studying the thermally induced spin transitions in a family of heterospin polymer chain complexes of [Cu.sup.2} hexafluoroacetylacetonate with two pyrazole-substituted nitronyl nitroxides. The studies have shown an efficient tool for characterizing the spin transitions and for understanding the temperature-dependent sign and value of the exchange interaction in strongly coupled spin triads.

An approach to pulse electron paramagnetic resonance (EPR) experiments which are based on two different resonance fields is introduced. Instead of using two microwave (mw) sources or a magnetic field jump, bichromatic pulses consisting of a transverse microwave field with frequency ω[sub mw] and a longitudinal radio frequency field with frequency ω[sub rf] are employed. Such bichromatic pulses excite a number of multiple photon transitions at frequencies ω[sub mw]+kω[sub rf] (k∈Z). The π-photon-induced transparency phenomenon is used to select the required transitions. This approach is used in the stimulated soft electron spin echo envelope modulation and the four-pulse double electron-electron resonance experiments. The results obtained using the bichromatic pulse approach are in agreement with those obtained with the standard pulse EPR techniques. It is shown that applying bichromatic pulses is straightforward and advantageous in several respects. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The exchange coupling of spin triads is analyzed in the complexes of [Cu.sup.2+] hexafluoroacetylacetonate with two pyrazole-substituted nitronyl nitroxides. The modulation of exchange interaction between copper and nitroxides by lattice vibrations lead to the spin exchange process.

The first stable, axial ligand mutations of a Cu(sub A) center in the Thermus thermophilus fragment of cytochrome ba(sub 3) have been realized. The mutants, Met160Gln and Met160Glu, show changes in the S-Cu charge transfer doublet centered near 500 nm and the near infrared transition at 790 nm. Both also have greater intensities and blue shifts of the higher energy CT partner of the doublet relative to wt. The blue shift of the S-Cu CT band in Met121Gln is consistent with a sulfur-to-oxygen substitution and a stronger ligand field.

Research into the impact of axial ligand mutation on the Cu(sub A) site in the recombinant water soluble fragment of subunit II of Thermus thermophilus cytochrome c oxidase ba3 is presented. It is concluded that the axial ligand has a small but significant impact on the spin distribution in the Cu(sub A) centre, reflecting on the ground-state wave function.

The design, construction, numerical modeling, and performance of a probehead for electron paramagnetic resonance (EPR) spectroscopy at 34–36 GHz is described. A classical cylindrical cavity operating in the TE011 mode with adjustable frequency and coupling has been found to be well suited for continuous wave and pulse EPR studies of frozen solutions of transition metal complexes at low temperature. The highest attention is given to the probehead performance in the pulse mode. The implemented design has been analyzed in detail using numerical modeling. The distribution of the electromagnetic fields, eigenfrequencies, quality factors, coupling coefficients, and conversion factors are calculated and compared with experimental data. The results demonstrate the effectiveness of the design and can serve as a guide for probehead optimization. [ABSTRACT FROM AUTHOR]

An approach to pulse electron paramagnetic resonance (EPR) experiments which are based on two different resonance fields is introduced. Instead of using two microwave (mw) sources or a magnetic field jump, bichromatic pulses consisting of a transverse microwave field with frequency omega(mw) and a longitudinal radio frequency field with frequency omega(rf) are employed. Such bichromatic pulses excite a number of multiple photon transitions at frequencies omega(mw)+komega(rf) (k in Z). The pi-photon-induced transparency phenomenon is used to select the required transitions. This approach is used in the stimulated soft electron spin echo envelope modulation and the four-pulse double electron-electron resonance experiments. The results obtained using the bichromatic pulse approach are in agreement with those obtained with the standard pulse EPR techniques. It is shown that applying bichromatic pulses is straightforward and advantageous in several respects.