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In the frame of the shell model approach to nuclear reactions, using the Green’s function formalism, the inelastic cross-sections are investigated. The analysis of the coupled-channel method based on the microscopical approach is given. The intermediate structure of inelastic cross-sections is analysed and compared with the experimental data.

We report the isolation and analysis of the rapidly reassociating DNA of the pathogenic, dimorphic fungus Candida albicans. Minicot analysis of whole-cell repetitive DNA suggested that a significant portion of this component was mitochondrial DNA. Genomic blot hybridizations in which radioactive whole-cell repetitive DNA was used as a probe revealed eight major EcoRI bands in the molecular weight range resolved by the gel system used. Isolation and analysis of high-purity mitochondrial DNA have shown that five of these bands are of mitochondrial origin. The remaining three bands are of nuclear origin and represent repetitive sequences that are found in the nuclear genome. Attempts to isolate nuclear DNA that was completely free of mitochondrial DNA contamination were unsuccessful.

Substantial changes in the state of a solid medium can occur under the expansion of a gas cavity therein. In particular, rupture of the brittle rock occurs. The nature of the motion of the ruptured rock differs substantially from the nature of the motion of the unruptured medium. Thus, a change in the density of the ruptured rock occurs under shear strains. This phenomenon is usually called dilatancy [1]. In addition, the strength characteristics also change under rupture of the rock. The stress state of a medium in the neighborhood of an expanding cavity at the time of cessation is analyzed in this paper. The influence of the ruptured rock characteristics on the magnitude of the residual stress is investigated. The radius of the rupture zone is determined and its dependence on the characteristics of the medium is investigated. The volume of the threshold space in the neighborhood of the cavity being formed because of dilatancy is calculated. The nature of the stress state in elastic-plastic media which do not dilate under plastic flow is also investigated.

We have continued the transcriptional analysis of the region of cytological locus 67B that contains the four small heat shock genes and other genes. Transcription from one of the heat shock genes in the region, hsp 26, takes place during high temperature treatment and at certain developmental stages, without heat shock, in several tissues, such as imaginal discs and adult ovaries. Observations of unexpected products after nuclease protection experiments periments provided the first indication of what genomic blot experiments showed to be small deletions. The alleles containing the deletion are expressed at the same level as the wild type allele. The deletion shortens the protein product, implying that it is in the coding region. Furthermore, flies homozygous for one of the deletion alleles are viable.

In the frame of the shell-model approach to nuclear reactions, using the Green function formalism, the total cross-section fluctuation is investigated. The role of the single-particle resonances in this fluctuation is discussed. The correlation function of the total cross section is evaluated in the presence of the doorway states. The intermediate structure in even and odd nuclei is analysed. The spin dependence of the neutron strength functions is estimated.

We isolated five Escherichia coli mutants deficient in their ability to support the late (replication-coupled) gene expression of T4 bacteriophage at 30 degrees C. These mutants, which we call Lit mutants, define at least one novel gene at 25 min on the E. coli map. They were selected in an attempt to obtain mutants which restrict the growth of T4 mutants deficient in polynucleotide 5'-kinase 3'-phosphatase but not that of wild-type T4 at 37 degrees C. Some of the mutants do have these phenotypes under some conditions. Studies of the block in T4 development in some of the E. coli mutants suggest that Lit mutants are affected in a gene product involved in the metabolism of deoxyribonucleic acid nicks or single-strand gaps. None of the Lit mutants is deficient in the major, bacterial, 3'-phosphatase activity in crude extracts.

A study was made of the effect of 60Co-gamma-radiation on the integrity of particles of the influenza virus and on the structure of some of its proteins. The physicochemical changes in virions were shown to depend upon radiation conditions. A conclusion is made that it is possible to use gamma-rays in the production of a centrifuged virion influenza vaccine.

Two bacteriophage T4-induced, nucleic acid-modifying activities, 5′ polynucleotide kinase and 3′ phosphatase, are both coded by the pse T gene. Therefore, the product of this gene is an enzyme which can remove phosphates from 3′ termini and add them to 5′-hydroxyl termini and thus could be said to “shuttle” phosphates on polynucleotides. This enzyme is sometimes required for T4 true-late gene expression, probably by helping establish the required intracellular DNA structure. Our data suggest that a host gene product normally can substitute for the product of the pse T gene, making it non-essential for phage multiplication on most laboratory strains of Escherichia coli .

Antiviral properties of Ingavirin were investigated in the Hep-2 cell culture with respect to the human respiratory tract virus (type 5 adenovirus). In concentrations of Ingavirin of 1000, 100 and 10 mcg/ml the generated posterity showed lower infective capacity (by 250, 100 and 10 times respectively). The electron microscopy of the infected cells confirmed the Ingavirin ability to disturb the adenovirus normal morphogenesis.

This research explored the feasibility of using the degradation rate of deoxyribonucleic acid (DNA) in human rib bone to determine the time interval since death. Postmortem human rib samples were surface sterilized and incubated under sterile conditions in either high or low humidity conditions at room temperature for a period of weeks. At selected times, portions of the bone were cut away, and the DNA from these samples was extracted and subjected to strand separating gel electrophoresis. The DNAs in the gels were transferred to a nylon membrane, preserving their relative positions as in the gel, and probed with radioactive total genomic human DNA. Autoradiograms produced were scanned and digitized. When the samples were incubated under identical conditions, the degradation rate of DNA in samples from different individuals appeared very similar. The DNA degradation rate may vary with temperature and humidity more than it varies between individuals.