Crystal structures and supramolecular features of 9,9-dimethyl-3,7-diazabicyclo[3.3.1]nonane-2,4,6,8-Tetraone, 3,7-diazaspiro[bicyclo[3.3.1]nonane-9,1′-cyclopentane]-2,4,6,8-Tetraone and 9-methyl-9-phenyl-3,7-diazabicyclo[3.3.1]nonane-2,4,6,8-Tetraone dimethylformamide monosolvate

Compounds (I), C9H10N2O4, (II), C1 1H12N2O4, and (III), C1 4H12N2O4-C3H7NO represent 9,9-disubstituted-3,7-diazabicyclo[3.3.1]nonane-2,4,6,8-Tetraone derivatives with very similar molecular geometries for the bicyclic framework: The dihedral angle between the planes of the imide groups is 74.87 (6), 73.86 (3) and 74.83 (6)° in (I)-(III), respectively. The dimethyl derivative (I) is positioned on a crystallographic twofold axis and its overall geometry deviates only slightly from idealized C2v symmetry. The spiro-cyclopentane derivative (II) and the phenyl/ methyl analog (III) retain only internal Cs symmetry, which in the case of (II) coincides with crystallographic mirror symmetry. The cyclopentane moiety in (II) adopts an envelope conformation, with the spiro C atom deviating from the mean plane of the rest of the ring by 0.548 (2) A ° . In compound (III), an N-H·O hydrogen bond is formed with the dimethylformamide solvent molecule. In the crystal, both (I) and (II) form similar zigzag hydrogen-bonded ribbons through double intermolecular N-H·O hydrogen bonds. However, whereas in (I) the ribbons are formed by two trans-Arranged O C-N-H amide fragments, the amide fragments are cis-positioned in (II). The formation of ribbons in (III) is apparently disrupted by participation of one of its N-H groups in hydrogen bonding with the solvent molecule. As a result, the molecules of (III) form zigzag chains rather than the ribbons through intermolecular N-H·O hydrogen bonds. The crystal of (I) was a pseudomerohedral twin. © Vatsadze et al. 2017

Crystal structures and supramolecular features of 9,9-dimethyl-3,7-diazabicyclo[3.3.1]nonane-2,4,6,8-Tetraone, 3,7-diazaspiro[bicyclo[3.3.1]nonane-9,1′-cyclopentane]-2,4,6,8-Tetraone and 9-methyl-9-phenyl-3,7-diazabicyclo[3.3.1]nonane-2,4,6,8-Tetraone dimethylformamide monosolvate

Compounds (I), C9H10N2O4, (II), C1 1H12N2O4, and (III), C1 4H12N2O4-C3H7NO represent 9,9-disubstituted-3,7-diazabicyclo[3.3.1]nonane-2,4,6,8-Tetraone derivatives with very similar molecular geometries for the bicyclic framework: The dihedral angle between the planes of the imide groups is 74.87 (6), 73.86 (3) and 74.83 (6)° in (I)-(III), respectively. The dimethyl derivative (I) is positioned on a crystallographic twofold axis and its overall geometry deviates only slightly from idealized C2v symmetry. The spiro-cyclopentane derivative (II) and the phenyl/ methyl analog (III) retain only internal Cs symmetry, which in the case of (II) coincides with crystallographic mirror symmetry. The cyclopentane moiety in (II) adopts an envelope conformation, with the spiro C atom deviating from the mean plane of the rest of the ring by 0.548 (2) A ° . In compound (III), an N-H·O hydrogen bond is formed with the dimethylformamide solvent molecule. In the crystal, both (I) and (II) form similar zigzag hydrogen-bonded ribbons through double intermolecular N-H·O hydrogen bonds. However, whereas in (I) the ribbons are formed by two trans-Arranged O C-N-H amide fragments, the amide fragments are cis-positioned in (II). The formation of ribbons in (III) is apparently disrupted by participation of one of its N-H groups in hydrogen bonding with the solvent molecule. As a result, the molecules of (III) form zigzag chains rather than the ribbons through intermolecular N-H·O hydrogen bonds. The crystal of (I) was a pseudomerohedral twin. © Vatsadze et al. 2017

The comprehensive approach to examination of female patients in diagnostic of benign diseases and breast cancer

The integrated approach to diagnosis and dispensary monitoring of women with high risk for breast cancer, the active detection of combined pathology of endometrium are promising directions in prevention and timely diagnosis of breast and uterus malignant neoplasms. The study established that particular correction of measures of secondary prevention of breast cancer is needed, including formation of risk group and organization of dynamic monitoring of women with high risk of breast cancer development. The comprehensive examination of reproductive system organs, including evaluation of risk factors, combined use of mammography and sonography methods to examine mammary glands and condition of endometrium, can to increase accuracy of differential diagnosis and to avoid unneeded invasive interventions with mammary glands and early diagnosis of endometrial pathology

Universality classes and critical phenomena in confined liquid systems

It is well known that the similar universal behavior of infinite-size (bulk) systems of different nature requires the same basic conditions: space dimensionality; number components of order parameter; the type (short- or long-range) of the intermolecular interaction; symmetry of the fluctuation part of thermodynamical potential. Basic conditions of similar universal behavior of confined systems needs the same supplementary conditions such as the number of monolayers for a system confinement; low crossover dimensionality, i.e., geometric form of restricted volume; boundary conditions on limiting surfaces; physical properties under consideration. This review paper is aimed at studying all these conditions of similar universal behavior for diffusion processes in confined liquid systems. Special attention was paid to the effects of spatial dispersion and low crossover dimensionality. This allowed us to receive receiving correct nonzero expressions for the diffusion coefficient at the critical point and to take into account the specific geometric form of the confined liquid volume. The problem of 3D⇔2D dimensional crossover was analyzed. To receive a smooth crossover for critical exponents, the Kawasaki-like approach from the theory of mode coupling in critical dynamics was proposed. This ensured a good agreement between data of computer experiment and theoretical calculations of the size dependence of the critical temperature T_c(H) of water in slitlike pores. The width of the quasi-elastic scattering peak of slow neutrons near the structural phase transition in the aquatic suspensions of plasmatic membranes (mesostructures with the typical thickness up to 10 nm) was studied. It was shown that the width of quasi-elastic peak of neutron scattering decreases due to the process of cell proliferation, i.e., with an increase of the membrane size (including the membrane thickness). Thus, neutron studies could serve as an additional diagnostic test for the process of tumor formation