Recent Papers

Corrections to the article Estimation of an Unknown Distribution Density from Observations (DAN, Vol. 147, No. 1, 1962)

Photosemiconductor properties of methyl chlorophyllide $\mathrm{a}$

This paper investigates the dark conductivity and photoconductivity of amorphous methyl chlorophyllide a layers prepared from chloroform solution, comparing their behavior with that of chlorophyll a and related organic semiconductors. Measurements in vacuum and oxygen atmospheres examine temperature…

Corrections to the Article Ferrites of the $\mathrm{MgO}$ – $\mathrm{MnO}_t$ – $\mathrm{Fe}_2\mathrm{O}_3$ System with an Addition of $\mathrm{Sc}_2\mathrm{O}_3$ (DAN, Vol. 148, No. 2, 1962)

Corrections to the article On the Gas-Chromatographic Determination of the Solubility of Gases and Vapors in Liquids (DAN, vol. 145, no. 5, 1962)

This biophysics paper concerns the threshold illumination on the eye pupil produced by a fixed light source and its dependence on background brightness at different retinal points. From the available translated text, the work is identifiable as an experimental or theoretical study of visual sensitiv…

Microbiological $20\alpha$-reduction of ketosteroids using Bacillus megatherium

This study examines the steroid-transforming activity of Bacillus megatherium strain VNIHFI-1 toward 16alpha,17alpha-oxidoprogesterone, a substrate lacking the 21-acetoxy group previously studied with this organism. Incubation with a growing culture produced a major transformation product that was i…

Structure of Blood Group Substances. Hydroxylaminolysis of Blood Group Substance $\mathrm{A}$ and the General Structure of the Biopolymer

This study examines the general structure of blood-group substance A by applying hydroxylaminolysis as a method for selective fragmentation of the biopolymer. The authors treated purified substance A with hydroxylamine, separated dialyzable and nondialyzable products by electrophoresis, chromatograp…

On the Oscillatory Nature of the Long-Wavelength Absorption Band of Tryptophan

This study examines the oscillator structure responsible for the long-wavelength absorption band of tryptophan near 280 mµ, addressing Weber’s proposal that more than one electronic transition contributes to the observed fluorescence polarization spectrum. Tryptophan was incorporated into polyvinyl …

Primary Structure of RNA. Interaction of RNA with $\mathrm{O}$-Methylhydroxylamine

This study examines whether O-methylhydroxylamine can be used to selectively modify cytosine residues in RNA and thereby facilitate selective enzymatic cleavage for primary structure analysis. RNA and polycytidylic acid were treated with O-methylhydroxylamine under mild conditions, followed by alkal…

Oligosides – a New Type of Plant Glycosides

This paper proposes “oligosides” as a class of plant glycosides containing more than four or five monosaccharide residues, based chiefly on systematic studies of triterpene saponins from several plant species. It summarizes methods for isolating and characterizing these compounds, including mild ext…

Corrections to the Article “Photochemical and Radiation-Chemical Reduction of Silver Perchlorate in the Presence of Organic Substances” (DAN, Vol. 148, No. 3, 1963)

Photochemical Oxidation of Chlorophyll $a$ in Frozen Solutions

This study examines whether chlorophyll a can undergo photochemical oxidation by oxygen in condensed systems where molecular diffusion and kinetic collisions are strongly suppressed. The authors irradiated oxygenated chlorophyll solutions frozen at liquid air temperature, recorded low-temperature ab…

THE EFFECT OF SOLUBILIZATION ON THE DENATURATION OF EGG ALBUMIN

This study examines how benzene solubilization affects the conformational stability of purified crystalline egg albumin during thermal and acid, alkaline denaturation. Using specific optical rotation as an indicator of conformational change, the authors compare untreated albumin solutions with solut…

Structure of Blood Group Substances. Proteolysis of Group Substance $\mathrm{A}$

This paper examines the structural organization of blood group substance A, with particular attention to the linkage between its carbohydrate and peptide components. The authors isolated a proteolytic enzyme from Asian influenza virus and used it to digest blood group substance A from pig stomach mu…

Synthesis of adenylyl- $(5'\to\mathrm{N})$ -phenylalanine methyl ester by the carbodiimide method

This paper addresses the preparation of nucleotide amino acid derivatives containing a phosphoamide bond, compounds of interest for studying nucleotide peptides and possible roles in cellular metabolism and protein biosynthesis. The authors synthesize the methyl ester of adenylyl-(5′ to N)-phenylala…

Corrections to the Article On Methods of Refinement Using Higher-Order Differences and $h^2$-Extrapolation (Doklady Akademii Nauk, Vol. 150,

Effect of Fixing Polypeptide Chains in Two Conformations

This paper investigates whether gelatin polypeptide chains can be chemically fixed in either helical or random coil conformations, whose interconversion strongly affects viscosity and gelation. Using purified isoelectric gelatin, chromium alum treatment at selected temperatures, dialysis, and measur…

Corrections to the Article Organic Derivatives of Kaolin (DAN, vol. 148, no. 2)

Ionization of bases and proton transfer in nucleic acids and their components

Using ultraviolet spectrophotometry over pH 1.8 to 12.5 and 20 to 80 degrees C, this study determines dissociation constants and thermodynamic ionization parameters for nucleic acid bases and nucleosides in ground and excited states. The authors compare acid and alkaline dissociation processes, note…

Corrections to the article Necessary and sufficient condition for the Fredholm property of the Dirichlet problem for a certain class of elliptic systems (DAN, Vol. 145, No. 4, 1962)

This text is a contents and corrections page for a scientific issue, listing articles across biophysics, biochemistry, botany, plant physiology, plant ecology, physiology, and embryology. The biophysics entry concerns threshold illumination at the eye pupil from a fixed light source as a function of…

Corrections to the paper On the spectral theory of non-self-adjoint differential operators (DAN, vol. 146, no. 6, 1962)

Errata to the Article “Radiation Method for the Synthesis of New Derivatives of Heterocyclic Compounds” (Doklady Akademii Nauk, Vol. 140, No. 6, 1961)

Corrections to the Article Determination of the Heat of Formation of Decaborane (DAN, Vol. 142, No. 5, 1962)

In the article by **G. M. Shavlovsky, E. M. Tsarenko, and I. S. Fiktash**, “Features of flavin synthesis by the yeast *Candida tropicalis* var. *rhagii*,” published in DAN, vol. 142, no. 4, 1962.

Corrections to the Article “On Integral Theorems for Large Deviations” (DAN, Vol. 138, No. 4, 1961)

Reaction of the $n$-nitrophenyl ester of carbobenzoxy-$D$-phenylalanine with chym

This study examines whether chymotrypsin forms a detectable acyl-enzyme intermediate during hydrolysis of the p-nitrophenyl ester of carbobenzoxy-D-phenylalanine, a D-amino acid ester expected to react more slowly than corresponding L-substrates. Kinetic measurements showed an initial burst of p-nit…

Electron microscope investigation of the supermolecular structure of poly $\gamma$ -benzyl- $L$ -glutamate

This study uses electron microscopy to examine how the conformation of poly-gamma-benzyl-L-glutamate macromolecules affects supramolecular structure formation after evaporation from different solvents. Solutions in benzene and chloroform, where chains are assigned to alpha-helical conformations, and…

Corrections to the article “On the Computation of the Index of an Isolated Fixed Point of a Completely Continuous Vector Field” (Doklady, Vol. 141, No. 2, 1961)

Corrections to the Article An Analogue of the Fortet–Kac Theorem (DAN, Vol. 137, No. 6, 1961)

Active principle of dendrodochin

This study examines the active toxic principle of dendrodochin, a metabolite of the fungus Dendrodochium toxicum with animal toxicity and antifungal activity. The authors cultivated a toxic strain under defined fermenter conditions, extracted toxic substances from acidified culture liquid with chlor…

BIOPHYSICS

| Authors and title | Pages |

This item comprises a contents page for several biological sections of a 1962 issue, listing papers in botany, plant physiology, physiology, and parasitology with their starting pages. It also includes a correction to V. Ya. Urm’s earlier article on necessary and sufficient stability conditions for …

ELECTRON-MICROSCOPIC STUDY OF SILICOSIS-HAZARDOUS DUST

This study examines dust generated during blasthole drilling in quartz-rich rocks of the Kizel coal basin using electron microscopy, with samples collected on nitrocellulose membrane filters and prepared as thin films. The observations distinguish large irregular mineral fragments, aggregates of hig…

PLANT EMBRYOLOGY

Corrections to the article On Some Congruences for the Number of Representations by Sums of an Odd Number of Squares (DAN, vol. 143, no. 2, 1962)

The role of day-length in the control of generation number and diapause of the apple-worm Laspeyresia pomonella L.

INVESTIGATION OF MOLECULAR MOTION IN AMYLOSE, LICHENIN, AND CELLULOSE BY THE METHOD OF NUCLEAR MAGNETIC RESONANCE

This study applies proton nuclear magnetic resonance to compare molecular motion in the polysaccharides amylose, lichenin, and cellulose, using vacuum dried samples measured from room temperature to minus 100 degrees Celsius. Line widths and second moments at 21 MHz were compared with those of malto…

In the article by G. M. Shavlovsky, E. M. Tsarenko, and I. S. Fiktash, “Features of flavin synthesis by the yeast *Candida tropicalis* var. *rhagii*,” published in *DAN*, vol. 142, no. 4, 1962:

Corrections to the Article On the Stability of Solutions of Second-Order Equations (DAN, Vol. 141, No. 6)

Thin-layer chromatography of sphingosine derivatives

This paper addresses the need for a rapid and reliable chromatographic method for identifying sphingosine bases and related derivatives, compounds that are difficult to separate by paper chromatography or by methods requiring chemical degradation. The authors develop thin-layer chromatography on sil…

Study of the Catalytically Active Centers of Lysozyme

This study examines whether the single histidine residue in lysozyme is essential to its catalytic activity. Lysozyme from hen egg white was selectively modified with iodoacetic acid at pH 5.5, the reaction products were separated chromatographically, and the modified protein was compared with nativ…

In the article by I. A. Rapoport, “Chemical mutations in the sex chromosome with a frequency above 50% and an increased fraction of semilethals,” published in *Doklady*, vol. 141, no. 6, 1962, p. 1479, line 11 from the bottom, instead of the printed “…diisopropylphosphoric acid…” it should read: diisopropyl fluorophosphoric acid.

PHYTOPATHOLOGY

Corrections to the article On glucosidation with 2-

HISTOLOGY

Corrections to the Article Equilibrium of Isomerization of Bromopropanes (DAN, Vol. 135, No. 2, 1960)

BIOPHYSICS

On the Time Required for the Establishment of a Stationary Amount of Oxygen in the Atmospheres of Planets Containing Water Vapor

This paper estimates how long photodissociation of water vapor by solar ultraviolet radiation could take to establish a stationary amount of free oxygen in a water-bearing planetary atmosphere, with particular reference to prebiotic Earth. Using a simplified isothermal atmospheric model, absorption …

Electron diffraction study of poly- $L$ -methyl- $\gamma$ -glutamate

This study applies electron diffraction to oriented films of poly-gamma-methyl-L-glutamate, a synthetic polypeptide used as a model for protein secondary structure. Diffraction patterns from stretched specimens were indexed with a hexagonal cell close to that known from X-ray work and showed feature…

On the Nature of Chlorophyll Fluorescence Quenching by Nitro Compounds

This study examines the mechanism of chlorophyll fluorescence quenching by aromatic nitro compounds, with particular attention to whether the primary act involves electron transfer. Fluorescence measurements in benzene solutions compared chlorophyll a, chlorophyll b, and pheophytin with nitrobenzene…

On the State of Water in the Chlorophyll Molecule

This study examines whether water is present in chlorophyll as a stoichiometrically bound component and how it interacts with chlorophyll a and b. Purified chlorophyll preparations were analyzed by infrared absorption spectroscopy in solid films and potassium bromide tablets, with spectra recorded b…