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The velocity, charge, and isotopic distributions of the products of nuclear reactions with 2 ≤ Z ≤ 11 have been studied in combinations of 18O (35 MeV/nucleon) + 181Та (9Ве) with a different isotope spin. The correlation of the isotope yields for the detected light elements with value Qgg has been established. The cross sections for the formation of neutron-rich nuclei have been measured and their yields in reactions with different neutron skin have been compared. A qualitative interpretation of the phenomenon of a significant increase in the probability of the formation of neutron-rich nuclei of light elements in reaction 18О (35 MeV/nucleon) + 181Та in comparison with 18О (35 MeV/nucleon) + 9Ве obtained in the reactions with the removal of a proton from the projectile nucleus has also been presented.

Low-molecular-weight metabolites known as mycotoxins of micromycetes from the genera Fusarium, Alternaria, Penicillium, Aspergillus, etc. were studied using the enzyme immunoassay in the brown algae Ascophyllum nodosum, Pelvetia canaliculata, Fucus vesiculosus, Laminaria digitata, and Saccharina latissima collected from the Kandalaksha Gulf, White Sea. The T-2 toxin, diacetoxyscirpenol, deoxynivalenol, zearalenone, fumonisins of group B, alternariol, ochratoxin A, citrinin, PR-toxin, mycophenolic acid, aflatoxin B1, sterigmatocystin, cyclopiazonic acid, emodin, roridin A, and ergot alkaloids were detected in thalli of A. nodosum, P. canaliculata, and F. vesiculosus. The latter species was found to contain almost all of the above-listed mycotoxins in significant amounts. P. canaliculata had lower levels of PR-toxin, mycophenolic acid, emodin, and roridin A than those recorded from A. nodosum, whereas the levels of the other substances did not differ significantly between these species. L. digitata and S. latissima contained only ergot alkaloids in trace amounts, and no other mycotoxins were detected.

The component composition and content of mycotoxins in perennial legumes of the genera Lathyrus (L. pratensis L., L. vernus (L.) Bernh., L. sylvestris L., L. niger (L.) Bernh., L. japonicus Willd., L. palustris L.) and Vicia (V. cracca L., V. sepium L., V. sylvatica L.) selected from natural biocenoses were studied. The greatest intensity of accumulation and diversity of fungal metabolites were found in meadow peavine, and the lowest intensity was in the peas. The general features and interspecific peculiarities of the mycotoxin profile in the plants of the genera Lathyrus and Vicia, as well as its variability in meadow peavine and cow vetch within different periods of vegetation, are discussed.

The component composition and content of mycotoxins in the terrestrial parts of perennial legumes of the genera Medicago (M. falcata L., M. lupulina L., M. sativa L.), Melilotus (M. albus Medik., M. officinalis (L.) Pall.), as well as Caucasian goat’s rue (Galega orientalis Lam.), Spanish licorice (Glycyrrhiza glabra L.), and Washington lupine (Lupinus polyphyllus Lindl.) selected from natural biocenoses within different periods of vegetation, were studied. The intensity of accumulation and the variety of fungal metabolites are most clearly expressed in licorice and lupine and more weakly expressed in goat’s rue; the species of alfalfa and melilot, the contamination of which did not differ noticeably, occupied an intermediate position. The general features and peculiarities of the mycotoxin profile during the period of vegetation in the plants of the genera Medicago and Melilotus are discussed.

The component composition and content of mycotoxins in perennial grasses of five species of the genus Trifolium, selected from natural biocenoses in different periods of vegetation, were studied. In the terrestrial parts of plants, the permanent presence of alternariol, cyclopiazonic acid, and emodin was shown. It was noted that differences in contamination are most clearly expressed in meadow clover Trifolium pratense L. and white clover Trifolium repens L., while alsike clover Trifolium hybridum L. occupies an intermediate position. It was found that zigzag clover Trifolium medium L. and mountain clover Trifolium montanum L., morphologically close to meadow clover, practically did not differ in the composition of toxic metabolites. The ways of formation of metabolic equilibrium in plants with participation of microscopic fungi are discussed.

The basic ion-optical characteristics of the luminosity and the high-resolution of kinematic separator COMBAS realized for the first time on the strong focusing principle are presented. The developed facility allows to separate the high-intensity secondary radioactive beams in a wide range of mass numbers A and atomic numbers Z which are produced in heavy ion reactions in the energy range of 20 ≤ E ≤ 100 MeV/A (Fermi energy domain). Two distinct detector systems such as realized Si strip detector telescope and the promising development of the three dimension time-projection chamber are discussed. Program of the investigations of nuclear reaction mechanisms at intermediate energies of 20–100 MeV/A, measurement of the radii of unstable nuclei, study of the cluster structure of light nuclei near the nuclear drip-line and search of 26,28O resonances in exchange reactions is proposed. The upgrading of experimental facility by the integration of COMBAS separator with the Ion Catcher is discussed.

The component composition of mycotoxin complexes is characterized in foliose lichens of the genera Nephroma, Peltigera, Umbilicaria, and Xanthoria. The interspecies differences in the genus Peltigera are expressed by the number of metabolites detected, from seven in P. aphthosa to three in P. canina, P. didactyla, P. praetextata, and P. rufescens. In Nephroma arcticum eight mycotoxins occurred regularly, with mycophenolic acid in especially high quantities in comparison with other lichens. In Umbilicaria, of six permanent components the content of alternariole is the highest, and in Xanthoria the content of emodine is the highest. Variation of the quantitative content of mycotoxins in general and of species of lichens is discussed, as is expansion of the background spectrum of these metabolites in collections from different territories.

Complexes of mycotoxins in fruticose lichens of 14 species belonging to five genera of the family Parmeliaceae were characterized by size, composition, and content of individual components. It was shown that species of the genus Bryoria always contain five mycotoxins (sterigmatocystin, mycophenolic acid, citrinin, emodin, and alternariol). In Evernia and Pseudevernia, this list is supplemented with zearalenone, diacetoxyscirpenol, and cyclopiazonic acid or fumonisins. It was noted that Alectoria and Usnea are distinguished by a peculiar set of toxic metabolites and occupy an intermediate position according to their number. The similarities and distinctions of the mycotoxin profile in species belonging to the same genus and in specimens from different habitats are discussed.

The (ΔE1, ΔE2, E) multidetector telescope has been developed and tested. The telescope is a compact combination of two 32-strip silicon ΔE1-, ΔE2-detectors and a scintillation E-detector, which is a 3 × 3 array of CsI(Tl) crystals. A timing signal can be obtained from any of the Si detectors for time-of-flight (TOF) measurements. Single-channel and 32-channel charge-sensitive preamplifiers have been developed and manufactured for the multidetector module to serve the ΔE- and E-detectors with high efficiency and sensitivity. Reaction products obtained in the 40Ar (35 MeV/nucleon) + 9Be reaction have been unambiguously identified in the experiment by mass number A and atomic number Z.

The distribution of mycotoxins anc unic acid in the thallus of epigenous fruticose lichens Alectoria ochroleuca; several species of the genera Cladonia, Cotraria, and Flavocetraria; foliose lichens Nephroma arcticum; and six species of the genus Peltigera were studied by mnzyme-linked immunosorbent assay. The mycotoxin content was lower in the top or apical parts of the thalli than in the basal parts and in dead areas. Differences in the distribution of usnic acid were insignificant in the majority of species, but in Cladonia stellaris and N. arcticum lichens the content of this metabolite in the upper and pc ripheral areas was higher than in the basal parts.

The development of an experimental facility based on the high-luminosity COMBAS fragment separator and a fast ion catcher is discussed. The main characteristics of the COMBAS fragment separator and the ion catcher determining the advantages of the proposed combination are presented. The developed facility is expected to allow production of secondary radioactive beams with a quality higher than the quality of beams obtained using the in-flight separation technique. It is planned that the facility will be used in a tandem with a post-accelerator for producing single-isotope and monochromatic high-intensity secondary radioactive beams in a wide range of mass numbers A and atomic numbers Z. A list of perspective scientific problems requiring high-intensity and high-quality secondary beams of exotic nuclei is proposed.

Secondary fungal metabolites (mycotoxins) in 22 lichen species of the families Parmeliaceae, Nephromataceae, Umbilicariaceae, Ramalinaceae, Cladoniaceae, Peltigeraceae, and Teloschistaceae were determined by enzyme-linked immunosorbent assay. The following mycotoxins were found in these lichens in a broad concentration range with a frequency of 70–100%: sterigmatocystin (7–2090 ng/g), alternariol (20–6460 ng/g), and emodin (45–94500 ng/g). Mycophenolic acid frequently occurred in 19 lichen species; citrinin, in 17 species; diacetoxyscirpenol, in 11 species; cyclopiazonic acid, in 10 species; and zearalenone, in 9 species. PR toxin was regularly detected in three lichen species; deoxynivalenol, fumonisins, and ochratoxin A, in two species; and T-2 toxin and ergot alkaloids, in one species. Aflatoxin B1 was detected in only six species with a frequency of 2–42%, whereas roridin A was present in 10% of Hypogymnia physodes samples.

The levels and frequencies of mycotoxin accumulation in lichens belonging to 20 genera of the families Cladoniaceae, Nephromataceae, Parmeliaceae, Peltigeraceae, Teloschistaceae, and Umbilicariaceae were characterized using enzyme immunoassay. Alternariol, sterigmatocystin, mycophenolic acid, citrinin, cyclopiazonic acid, and emodin were regularly detected in all genera, except for Peltigera, at an average level of more than 1000 ng/g (i.e., 0.0001%). The necessity for the safety monitoring of drugs based on lichen extractives is discussed.

An enzyme immunoassay for usnic acid in lichens was developed, the sensitivity of which was 0.1 μg/g of air-dried material (0.00001%). Polyclonal rabbit antibodies against bovine serum albumin conjugated to (+)-usnic acid under the conditions of formaldehyde condensation made it possible to determine the analyzed substance in solutions at concentrations from 1 ng/mL when it interacts with immobilized gelatin conjugate homologous in the binding mode. Usnic acid in 2–26600 μg/g (0.0002–2.6%) amounts was found in all 236 studied samples of lichens belonging to 53 species and 8 families.

The composition of low-molecular biologically active metabolites typical of microscopic fungi has been studied in blastemas of fruticose lichens of the genera Cladonia, Cetraria, Evernia, Bryoria, and Usnes. The enzyme immunoassay method showed the presence of sterigmatocystin, emodin, mycophenolic acid, citrinin, alternariol, and diacetoxyscirpenol, which occurred regularly and, in most cases, at a frequency of 55 to 100%. The highest levels of accumulation were 0.001–0.003% for emodin, 0.0002% for alternariol and citrinin, 0.0001% for sterigmatocystin and mycophenolic acid, and 0.00005% of the weight of air-dry material for diacetoxyscirpenol. Other metabolites (cyclopiazonic acid, ergot alkaloids, ochratoxin A, PR toxin, deoxynivalenol, zearalenone, and fumonisins) were detected in these lichens less frequently (sometimes only upon the expansion of the territory of sampling), and their content was no more than 0.00005%. The peculiarities of the component composition and the levels of accumulation of fungal metabolites in lichens of different taxonomic affiliation were discussed.

The basic ion-optical characteristics of the COMBAS fragment separator are analyzed. The momentum distributions of radioactive 6He, 8He, and 9Li nuclei obtained in the reaction 11B (33 A MeV, where A is the mass number of a particle) + 9Be (332.6 mg/cm2) have been investigated in forward-angle measurements on the COMBAS fragment separator. The momentum and angular (horizontal) acceptances of the COMBAS separator have been measured using the 6He, 8He, and 9Li beams. It has been ascertained that the images of the 6He, 8He, and 9Li nuclear beams in final achromatic focus of the separator Fa approximately twofold exceed the size of the beam on a producing target (input focus F0), at which the primary beam has a diameter of 6 mm. The intensities of 6He, 8He, and 9Li beams obtained at a 5-μA intensity of the primary 11B beam are 6.9 × 105, 2 × 104, and 4.7 × 105 particles/s, respectively. These values are sufficient for use in spectroscopic measurements. It is proposed that time-of-flight analysis of nuclear reaction products at the exit from the COMBAS separator will be used not only to measure the energy of transported particles over the whole operating range of the momentum acceptance, but also to identify them by mass A and charge Z without loss of these particles. The problem of reducing the count rates of detectors and further improvement of their energy resolution for detected particles can be solved by placing a high-resolution magnetic spectrometer past the second target accepting the secondary radioactive nuclear beams.

A proportional counter designed for heavy ion flux measurements is described. The working gas of the counter is air. The counter is composed of three parallel glass-fiber frames with wire electrodes coiled on them. Based on the counter, there has been developed a diagnostic product measuring the density distribution of accelerated ion flux for radioelectronic device testing. To prevent the dependence of measurement results on weather conditions (atmospheric pressure, temperature, humidity) as well as on the type and energy of ions, there has been applied an automatic correction methodology. In the process of the set-up operation it has been established, that the counter is characterized by a high radiation resource, resistance to extreme downloads, adequate performance of up to 106 ions/s, it is not sensitive either to neutrons or to γ-quanta, and it is convenient to use.

Using the reaction of activated N-hydrooxisuccinimide ester of mycophenolic acid, a series of immunoreactive conjugated antigens with albumins, gelatin, and glucosoxidase is obtained. On the basis of polyclonal rabbit antibodies, a test-system for indirect competitive immunoenzyme analysis is elaborated, which has the sensitivity 0.4 ng/ml. By immunoanalysis, the ability for active biosynthesis of mycophenolic acid in strains of Byssochlamys nivea (44/44, 4100-68400 ng/ml) and Penicillium roqueforti (7/16, 204-25120 ng/ml) from the mycobiota of ensiled feeds is confirmed. The correspondence between weakly expressed producing capacity of most species of fungi of the genera Penicillium and Aspergillus prevailing in grain feeds and the data on low occurrence of this metabolite in grain (8.0%) and combined feeds (11.9%) is confirmed. A potential relationship between particular cases of a significant accumulation of mycophenolic acid (from 500 to 1500 μg/kg) in grains of wheat, corn, and combined feeds and a high biosynthetic activity in rare species P. puberulum, P. stoloniferum, and P. gladioli is discussed.

An monitor for control of accelerated particle flux density used in irradiation of polymer films with heavy ions with a low track density (103−5 × 107 cm−2) is based on detection of recoil protons. It has been designed to control irradiation of a film with a width of up to 650 mm and is composed of five PIN diodes with a hydrogenous target placed in front of each diode. The sensitivity of the monitor with a polyethylene target to the density of a xenon ion beam is described by a linear function; its value is (4.0±0.5) × 10−3 pulses/(ion/cm2). The instrument is capable of monitoring ion flux densities of

Kinematics of two-body Coulomb breakup of a prototype 11B nucleus into 4He and 7Li fragments is considered. The factors affecting the accuracy in measuring the breakup parameters are analyzed, and the corrections having an influence on the accuracy in reconstructing the primary parameters of the cluster breakup are estimated. A method for estimating the effect of an unknown contamination in the target and the use of this method for separating true and background events are discussed. The influence of background factors occurring in heavy ion fragmentation reactions is analyzed, and random coincidences due to high background fluxes of parasitic products are estimated. It is proposed to use magnetic analysis of correlated breakup products to reduce the background particle flux and substantially (by several orders of magnitude) improve the accuracy in measuring the cluster energies.

A rapid method for the determination of citrinin in feed using an indirect competitive enzymelinked immunosorbent assay after analyte extraction from test samples with aqueous acetonitrile was developed. Within the analytical concentration range 20–500 μg/kg for citrinin, the relative characteristics of the repeatability (precision) and intralaboratory intermediate precision (reproducibility) of analytical results were 0.11 and 0.16, respectively.

The use of an indirect competitive enzyme-linked immune sorbent assay (ELISA) involving polyclonal rabbit antibodies against BSA-conjugated PR-toxin (sensitivity, 1 ng/ml) established the ability to synthesize PR-toxin in 18 out of 35 morphologically identified strains of Penicillium roqueforti and P. chrysogenum. The results indicate that ELISA for PR-toxin may be used in assessing the taxonomical position of terverticillate penicillia in the presence of other micotoxins.