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Laboratory animals (the California rabbit) were immunized with natural preparations of Saccharomyces cerevisiae and Candida krusei yeasts. The resulting sera have been analyzed with ligand libraries constructed from synthetic oligosaccharides related to the main carbohydrate components of the fungal cell wall. It is shown that the antibodies in the studied sera predominantly recognize mannan fragments, with the carbohydrate specificity profile being different for S. cerevisiae and C. krusei. Sera against S. cerevisiae contained antibodies that recognize β-glucan, and the minimal recognizable epitope is linear trisaccharide. These results are necessary for the creation of needed immunoenzyme diagnostics for the detection and species characterization of fungi.

Brush rabbits were immunized with injections prepared from the fungi Aspergillus fumigatus, Aspergillus niger, and Aspergillus repens. A library of synthetic biotinylated oligosaccharides containing the key fragments of antigenic polysaccharides of the fungal cell wall—galctomannan, α- and β-glucans, mannan, and chitin—was used to analyze carbohydrate specificity. The anticarbohydrate antibodies obtained from animals immunized with preparations from A. fumigatus and A. repens predominantly recognized epitopes containing galactofuranoside residues, while the majority of the antibodies against A. niger bound the chitooligosaccharide ligand. These results are the basis for the identification of specific markers required for the development of immunoenzyme test systems.

Original data on the survival of fungal spores exposed to space conditions are presented. The experiment was carried out on the Earth-orbiting Russian satellite Foton-M4. The flight duration of the satellite was 45 days. Thirteen fungal species (hyaline as well as pigmented) from 10 genera recovered from destructed stone materials were studied. Sterile quartz sand was inoculated by the fungal spores and was placed into Eppendorf tubes. During the space flight, the Eppendorf tubes with fungal spores were kept inside the Foton descent capsule in the “Biokont” containers and on the external surface of the capsule in the “Exobiofrost” containers exposed to the open space as well. Spores of ten species (77% of all tested species), i.e. Acremonium charticola, Aspergillus niger, Aspergillus versicolor, Chaetomium globosum, Cladosporium sphaerospermum, Penicillium chrysogenum, Penicillium verrucosum, Purpureocillium lilacinum, Sarocladium kiliense, and Trichoderma harzianum, survived after the flight both inside and outside the descent capsule. Only three species (23% of all tested species), i.e. Acremonium furcatum, Engyodontium album and Verticillium zaregamsianum, failed to survive outside as well as inside the capsule. Spore viability differed depending on the fungal species. Thus, spores of some fungal species are able to survive under the complex of stress factors such as low temperature values, radiation, etc. We have shown that micromycetes can be used as a model group for study of eukaryotic organisms’ resistance to stress factors, due to their high tolerance not only to extreme terrestrial environments, but to the extraterrestrial ones as well.

Long-term microbiological investigation of the pollen of silver birch (Betula pendula) in the Moscow and Moscow oblast areas revealed that almost one-third of the analyzed samples contained the fungus identified by morphological, cultural, and molecular genetic techniques as Quambalaria cyanescens (de Hoog & G.A. de Vries) Z.W. de Beer, Begerow & R. Bauer. This species was previously known mostly as a symbiont of tropical plants of the genera Eucalyptus and Corymbia and have not been isolated in Russia. We revealed a close association between Quambalaria cyanescens and silver birch. The micromycete was regularly detected in pollen samples, as well as on the inside and outside of the aments, and on the surface of leaves and branches. It was never isolated from other plant species in the investigated area. The data on the morphological and cultural characteristics of the fungus, its cell ultrastructure, and occurrence are presented, as well as the phylogenetic analysis of the isolated strains.

The specific features revealed in the behavior of temperature dependences of the spin-lattice relaxation time t 1 of quadrupole nuclei involved in different types of thermally activated motions in crystals have been analyzed under the assumption that there exists a temperature dependence of the activation energy of motion. An expression for the spin-lattice relaxation rate has been obtained. This expression includes the effect under consideration and provides an adequate explanation for numerous anomalies in the behavior of the experimental dependences t 1(T), which were revealed in the case of the motion of molecular fragments with a relatively large volume. A nontraditional method for evaluating the activation energy of motion under these conditions has been proposed.

Original data on the study of the population dynamics in allergenic house dust mites of the family Pyroglyphidae (Dermatophagoides pteronyssinus (Trouessart 1897) and D. farinae Hughes 1961) during long (37 weeks) joint cultivation with the micromycetes Aspergillus penicillioides Speg. in simple periodical cultures without addition of food (SPC) with different initial population density of mites are given. The micromycete A. penicillioides Speg., dominating in laboratory cultures of pyroglyphids, was cultivated in parallel without mites. It was found that during joint cultivation of A. penicillioides and mites, population dynamics of D. pteronyssinus and D. farinae in SPC depended on the initial population density of mites, which affected the duration of mite developmental stages and the degree of the maximal population density. Cultures of D. farinae developed more rapidly than cultures of D. pteronyssinus, independently of the initial population density (50 or 200 specimens per gram of the substrate). A high degree of the initial population density in both mite species resulted in the shortening of the lag-phase, in more rapid reaching of the maximal population density, and in the higher degree of the maximal population density. Population density of the fungus A. penicillioides did not depend on the presence of both mite species. On the basis of our own data and literary analysis, we assume that A. penicillioides can affect the ability of mites to explore the trophic substrate, the rate of the population development, and the degree of their maximal population density. Mites, in their turn, did not significantly affect the development of A. penicillioides in our experiments.

The pseudorotation of chlorine atoms in molecular complexes of SbCl3 with benzene and its substituted derivatives was used as an example to consider the effect of the thermally activated intramolecular mobility on the quadrupole spin-lattice relaxation of moving nuclei. The data obtained by nuclear quadrupole resonance were analyzed using the model that implies the existence of a temperature dependence of the activation energy for pseudorotation. This model accounts for the great preexponential factors in the expression for the thermal activation component of the relaxation rate of chlorine nuclei found for some complexes and provides the way for rapid estimation of the pseudorotation activation energy in the characteristic temperature points using both relaxation and spectral NQR parameters.

The possibility of estimating the activation energy Ea of reorientation of symmetrical atomic groups containing quadrupole nuclei from nuclear quadrupole resonance data was studied. The estimates can be obtained using simple semiempirical equations relating the Ea value to the characteristic temperature selected in some general way for different compounds; the measured NQR parameters are determined at this temperature by reorientation motion. The temperature at which the spin-lattice relaxation time of a moving quadrupole nucleus is 1 ms and the fade out temperature of the NQR signal for the group that experiences reorientation (fading is related to the maximum measurable width of resonance lines) were tested as characteristic temperatures. The 35Cl NQR data on 70 reorienting CCl3 groups were analyzed to obtain quantitative relations of the Ea = CTchar type that described the reorientations of these groups in solids. Some corollaries to the equations obtained are discussed.

Long-term microbiological investigation of the pollen of silver birch (Betula pendula) in the Mos- cow, and Moscow region areas revealed that: almost one-third of the analyzed samples, contained the fungus identified by morphological, cultural, and molecular genetic techniques as Quambalaria cyanescens (de HoogG. A. de Vries) Z.W. de Beer, BegerowR. Bauer. This species was previously known mostly as a syrmbiont of tropical plants of the generaEucalyptus and Cortyminbia and has not been isolated in Russia. We revealed a close association between Quambalaria cyanescens and silver birch. The micromycete was regulaly detected in pollen samples, as well as on the.inside and outside of the aments, on the surface of leaves and branches. It was never isolated from other plant species in the investigated area. The data on the morphological and cultural characteristics of the fungus, its cell ultrastructure, and occurrence are presented, as well as the phylogenetic analysis of the isolated strains.

Nuclear quadrupole resonance (NQR) spectra of chlorine and antimony in the 2SbCl3 · C6H6 complex and their temperature behavior between 77 K and the melting point were studied. The spectral lines of two nonequivalent SbCl3 moieties are compared with available X‐ray diffraction data. An analysis of the temperature dependence of the resonant frequency and the spin–lattice relaxation time for 35Cl nuclei showed the existence of thermally activated, intramolecular motion of chlorine atoms in this complex. The nature of the motion is determined by the shape of the SbCl3 moieties. The activation energies of the motion were obtained for the two structurally nonequivalent halves of the complex (75.5 and 79.5 kJ/mole).

The 35Cl NQR frequencies and the spin-lattice relaxation times have been investigated for the solid cyclic chlorophosphoranes Cl3PO2C6H4 (I), ClP (O2C6H4)2 (II) and CCl3Cl2PO2C6H4 (III) at different temperatures. In crystalline compound I, thermoactivated motion involving the chlorine atoms of the PCl bonds has been revealed. This motion is due to intramolecular positional exchange of one axial and two equatorial chlorine atoms with an activation energy of 46.5 kJ mol−1. Earlier results obtained by means of the 35Cl NQR method for chlorine positional exchange in some other solid chlorophosphoranes are summarized.

Temperature dependences of35Cl NQR frequencies and spin-lattice relaxation times were measured for the CCl3 groups of compounds CCl3CH=CHR and CCl3CH=CR2 with R=COCH3 and COOCH3. The activation energies of CCl3 reorientations reflect the significant contribution of intermolecular steric interactions to the value of the potential barrier hindering these reorientations. In the CCl3CH=CHCOCH3 crystal, the reorientations of the CCl3 group are hindered more than those of the molecule as a whole.

Temperature dependences of the 35Cl and 121Sb spin-lattice relaxation time τ1in antimony trichloride complexes with p-xylene and acetophenone were studied using NQR spectroscopy. The activation energies of the retarded motion (similar to that discovered in some vπ complexes of SbCl3) of chlorine atoms were determined from the 35Cl τ1(T) function. New data on the shape of the 121Sb τ1(T) function are discussed.

The effect on the 35Cl quadrupole relaxation of modulations of the electric field gradient by thermally activated motions of nearby nonbonding symmetric and asymmetric atomic groups has been investigated. This way the activation energy of the motions has been determined and the fraction of the electric field gradient influenced by the motions has been estimated. This fraction can be taken as a measure of the intensity of nonbonding interactions in solids.

In this work information on the biology and ecology of synanthropic mites and mold fungi, proved to be the sources of indoor allergens in different premises, is presented. The authors propose the algorithm of the ecological monitoring of dwellings, developed on the basis their investigations. The types of dwellings, the time and situations when ecological monitoring should be carried out are analyzed. Grounds for the necessity of controlling the number of mites and the concentration of Micromyces spores, as well as their elimination from the environment, are given.

The CCl3 group mobility in crystals of (CCl3)mPR5-m and (CCl3)mCl3-mP=NR′, m = 1, 2, is studied by NQR methods, using temperature dependence measurements of both the resonance frequencies and the spin-lattice relaxation times for 35Cl nuclei. There are differences between the CCl3 group motions in these crystals due to differences in steric interactions. In the first case the reorientation motions of the axial trichloromethyl groups are strongly hindered. In the second, reorientations take place, with the motions of the two CCl3 groups which are bonded to the same phosphorus atom different as a result of differences in the potential barriers associated with the nonequivalent CCl3 groups in the molecule.

The effects of molecular reorientations between three unequal potential wells on the quadrupole relaxation of nuclei, both taking part in this motion directly and being connected with moving atomic groups by the nonvalent interaction have been considered theoretically. The results of this consideration have been used for a quantitative interpretation of the experimental data obtained by the 35Cl NQR techniques for the Cl3P = NCCl(CF3)2 crystal where the motion of the asymmetric CCl(CF3)2 fragment between three unequal wells has been observed.

The temperature dependence of the 35Cl NQR frequencies, their temperature coefficients, and spin-lattice relaxation times was studied for crystalline compounds ClxH3−xCR with RC6H5, COOH, and CONH2−y(CH3)y(x=1,2 and y=0,1,2) in the temperature range from 77 K to the sample melting points. It is found that for the mono- and dichloromethyl groups the shape of the experimental curves on the upper part of the temperature range often differs essentially from that predicted by the Bayer theory. These deviations may be interpreted as due to the appearance of the considerable anharmonicity of the autonomous librations of the groups mentioned.

The 35 Cl NQR frequency ν and the spin-lattice relaxation time T 1 have been investigated in solid tetrachlorophosphoranes C 6 H 5 PCl 4 , 4-ClC 6 H 4 PCl 4 and 2,6-Br 2 -4-ClC 6 H 2 OPCl 4 at temperatures from 77 K to the melting points. The fading of the NQR signals and the exponential shortening of the T 1 time for the chlorine nuclei in the PCl bonds show the existence of the exchange motion (pseudorotation) in these solids which involves three or four chlorine atoms corresponding to their interactions with the environment. The activation energies of the motion are found to lie in the range 40–70 kJ mol −1 .

The nuclear quadrupole relaxation time T 1 temperature dependence is studied experimentally for the 35 Cl nuclei in some Cl 3 PNR-type crystals. The conventional additive libration-reorientation scheme of the relaxation mechanism is accepted. Using this scheme, the T 1 temperature dependence experimental data are analyzed. The results obtained make it possible to prove the existence of the PCl 3 group autonomous reorientations and to find the values of all the parameters characterizing the relaxation processes.

The temperature dependence of the cnlorine-35 nuclear quadrupole spin-lattice relaxation time, obtained for the (CI 3 PNCH 3 ) 2 crystal, shows the existance of a thermal-activated process with the energy barrier 25 kcal/mole. This process seems to be connected with the intramolecular rearrangement of the chlorine nuclei, the most probable mechanism being a trigonal twist which is one of several kinds of ligand exchange taking place in pentacoordinated phosphorus molecules. The effects of such a motion in NCR are discussed.

The NQR frequency ν and the spin-lattice relaxation time T1 of 35Cl nuclei in crystalline (ω,ω)-dichlorotoluene, C6H5CHCl2, have been measured at temperatures above 77 K. The existence of a second-order phase transition was discovered at Tc = 94 K. At this point the low-temperature NQR spectrum consisting of five lines passes into the high-temperature doublet. The behaviour of ν and T1 as functions of temperature near the critical point Tc is investigated and corresponding parameters are obtained. The NQR signals fade out about 185 K due to the reorientational motion with the potential barrier of 33.9 kJ/mole.

Nuclear quadrupole resonance and nuclear magnetic resonance methods have been used to study the pseudorotation process in solids. In crystalline dimeric (Hal3PNR)2 phosphazo compounds, where Hal = CI or F, and R contains protons, the temperature dependences of the 35CI, 19F and 1H spectra and the relaxation times indicate intramolecular exchange of the ‘trigonal twist’ type between one axial and two equatorial halogen atoms attached to the pentacoordinated phosphorus. The activation energy, Ea, for the exchange process is obtained from the T1 temperature dependence of the 35CI nuclei and from the T1e temperature dependence of the 19F and 1H nuclei. In the case of chlorinated phosphazo compounds, Ea, lies in the 59-105 kJ mol−1 range, whereas in solid (F3PNCH3) Ea, is about 38 kJ mol−1.

In the present paper we describe the 35Cl NQR investigation of PCl3-reorientations in the molecules of three trichlorophosphazocompounds, Cl3P=NCC1(CC13)2 (I), C13P=NP(O)(CC13)2(II), C13P=NCOCF3 (I...