Upper Limit on the Photoproduction Cross Section of the Spin-Exotic π_{1}(1600).

The spin-exotic hybrid meson π_{1}(1600) is predicted to have a large decay rate to the ωππ final state. Using 76.6  pb^{-1} of data collected with the GlueX detector, we measure the cross sections for the reactions γp→ωπ^{+}π^{-}p, γp→ωπ^{0}π^{0}p, and γp→ωπ^{-}π^{0}Δ^{++} in the range E_{γ}=8-10  GeV.

Synthesis and optical properties of perovskite nanocrystals in glass with cationic substitution.

The effect of cadmium ions introduced into fluorophosphate glass on the growth and photoluminescence (PL) of the CsPb1-xCdxBr3 perovskite nanocrystals (NCs) is systematically studied. The x-ray diffraction patterns have shown that cadmium ions are really incorporated into the NCs that results in a decrease in the lattice constant from 5.85 (x = 0) to 5.

Measured proton electromagnetic structure deviates from theoretical predictions.

The visible world is founded on the proton, the only composite building block of matter that is stable in nature. Consequently, understanding the formation of matter relies on explaining the dynamics and the properties of the proton's bound state. A fundamental property of the proton involves the response of the system to an external electromagnetic field.

Ruling out Color Transparency in Quasielastic ^{12}C(e,e^{'}p) up to Q^{2} of 14.2 (GeV/c)^{2}.

Quasielastic ^{12}C(e,e^{'}p) scattering was measured at spacelike 4-momentum transfer squared Q^{2}=8, 9.4, 11.4, and 14.

Probing the Deuteron at Very Large Internal Momenta.

We measure ^{2}H(e,e^{'}p)n cross sections at 4-momentum transfers of Q^{2}=4.5±0.5  (GeV/c)^{2} over a range of neutron recoil momenta p_{r}, reaching up to ∼1.

First Measurement of Near-Threshold J/ψ Exclusive Photoproduction off the Proton.

We report on the measurement of the γp→J/ψp cross section from E_{γ}=11.8  GeV down to the threshold at 8.2 GeV using a tagged photon beam with the GlueX experiment.

Phenotypic effect of substitution of allelic variants for a histone H1 subtype specific for growing tissues in the garden pea (Pisum sativum L.).

In pea, subtype H1-7 of histone H1 is specific for young actively growing tissues and disappears from chromatin of mature tissues. We sequenced the alleles coding for three main variants, numbered according to the increase of the electrophoretic mobility. Allele 1 differs from the most common allele 2 by eight nucleotide substitutions, two of them associated with amino acid replacements, His->Tyr in the globular domain and Ala->Val in the C-terminal domain.

Structure of allelic variants of subtype 5 of histone H1 in pea Pisum sativum L.

The pea genome contains seven histone H1 genes encoding different subtypes. Previously, the DNA sequence of only one gene, His1, coding for the subtype H1-1, had been identified. We isolated a histone H1 allele from a pea genomic DNA library.

A mutation, tl2, in pea (Pisum sativum L.) affects leaf development only in the heterozygous state.

After gamma irradiation of pea seeds, a mutation designated as tendril-less2 (tl2) was induced. In the heterozygous state, it transforms tendrils into very narrow leaflets that resemble the heterozygote phenotype of the classic tl mutation. The tendrils of the double heterozygote tl2/+, tl/+ are converted into oval leaflets.

Evolution of the regular zone of histone H1 in fabaceae plants.

An analysis of the histone H1 subtype, H1-1, in eight legumes belonging to four genera of the tribe Vicieae (Pisum, Lathyrus, Lens, and Vicia), revealed an extended region consisting of the tandemly repeated AKPAAK motifs. We named this region the Regular zone (RZ). The AKPAAK motifs are organized into two blocks separated by a short (two or six amino acids) intervening sequence (IS).

Large changes in the structure of the major histone H1 subtype result in small effects on quantitative traits in legumes.

Electrophoretic analysis of the most abundant subtype of histone H1 (H1-1) of 301 accessions of grasspea (Lathyrus sativus) and 575 accessions of lentil (Lens culinaris) revealed allelic variants which most probably arose due to recent mutations. In each species, a single heterozygote for a mutation was taken for construction of isogenic lines carrying different H1-1 variants. Sequencing of alleles encoding H1-1 in lentil, grasspea, pea and Lathyrus aphaca showed the presence of an extended region in C-terminal tail which we termed 'regular zone' (RZ).

Tertiary trisomics in the garden pea as a model of B chromosome evolution in plants.

It is hypothesized that, in plants, genetically empty B chromosomes may originate from the extra chromosome (E) of tertiary trisomics if (i) the region of basic chromosomes homologous to the E (H-region) harbors a sporophytic lethal covered by the wild-type allele in E, and (ii) crossing-over between E and the H-region is suppressed. Under these conditions, most loss-of-function mutations occurring in the H-region are deleterious for haploid gametophytes, whereas those occurring in E are neutral or advantageous for hyperploid (n+1) gametophytes. As a result, natural selection at the gametophyte level can lead to the degeneration of E, leaving the H-region intact.

Mortality of pollen grains may result from errors of meiosis: study of pollen tetrads in Typha latifolia L.

In the cattail Typha latifolia the four haploid products of meiosis remain attached and form the flat tetrad of pollen grains. Gametophytic lethals arisen de novo in diploid cells of sporophyte must manifest themselves as pollen tetrads with two dead grains. This could allow to estimate the rate of recessive lethals arresting pollen grain development.

[Structural characteristics of lysine-rich histone from the sperm of a mollusk Anodonta piscinalis].

Sperm of freshwater bivalve mollusk Anodonta piscinalis was found to contain two fractions of lysine-rich histone: somatic histone H1 and sperm-specific protamine-like histone, named Hp. A detailed analysis of H1 and Hp structure was carried out by means of N-bromosuccinimide, chymotrypsin and pepsin cleavage followed by determination of the lysine residue number, positive charge and molecular length of obtained fragments by the method of incomplete succinylation. It has been shown, that Anodonta histone H1, like the avian histone H5, contains 3 tyrosine residues in the central hydrophobic domain of the molecule.

[Evolutionary interrelationship of histones H1 and H5 in vertebrates].

Lysine-rich histones of some amphibians and fishes were studied. Electrophoretically purified subfractions were cleaved at residues of tyrosine, methionine, aspartic acid and phenylalanine. The fragments thus obtained were investigated by the method of incomplete succinylation which permitted us to determine the number of lysine residues, positive charge in acid conditions and molecular lengths of polypeptides.

[Determination of lysine residue number, positive charge and molecular lengths of histone H1 and H5 by a method of incomplete succinylation].

A simple method for determination of lysine residue number and positive charge of histones H1 and H5 in the acetic acid -- urea system has been developed. The method is based on incomplete succinylation of lysine residues and allows an accurate determination of protein molecular length. The accuracy of the method has been demonstrated by determination of goose and chicken histones H5 and their fragments.

[Molecular variants of histone H5 of linnet (Acanthis flammea)].

Five electrophoretic variants of H5 histone were detected in the population of linnet (Acanthis flammea). Using the method of incomplete succinilation the number of lysine residues, electrophoretic positive charge and molecular length were determined for some variants of H5 histone and for their fragments, obtained after treatment with n-bromosuccinimide and chymotrypsin. The difference in structure of H5 variants was found to be connected with the region, confined by the phenylalanine residue and the C-end of the molecule.

[Histone H1 of reptiles, homologous to histone H5 of birds].

Lysine-rich histone H1 of animals from three reptilian orders was studied. Electrophoretically pure H1 histone subfractions were cleaved at residues of tyrosine, methionine, aspartic acid and phenylalanine. The fragments obtained were studied by modified method of incomplete succinylation which permitted to determine the number of lysine residues, the positive charge and molecular length of polypeptides.

[Histones of Salmonidae fishes. Comparative study of histones from different species and intraspecies variability of Oncorhynchus nerka H1].

The comparative electrophoretic properties of erythrocyte histones from 7 Salmonidae species were investigated. Using Na-SDS gel electrophoresis, it was shown that all the species studied possess the erythrocyte-specific fraction of histone H5. High resolution gel electrophoresis in acetic acid--urea gels demonstrated differences in the subfractional composition of histone H1 from erythrocytes and liver of O.

[Dansylated amino acid separation by polyacrylamide gel electrophoresis].

The paper describes a method for separation of dansylated amino acids by polyacrylamide gel electrophoresis. The methods allows a simultaneous analysis of 20-30 samples. The sensitivity of the method is 1 x 10(-9)-1 x 10(-10) M amino acid.

[Microelectrophoretic analysis of histones from single chromosomes and nucleoli of mosquito (Chironomis plumosus) larvae].

A simple method of microelectrophoresis for histone analysis from single fragments of polythenic chromosomes of chironomid salivary glands has been developed. The chromosomes or their fragments obtained micrurgically were dissolved in a microdroplet of 8 M urea and 1 N sulfuric acid solution. Electrophoresis was performed in 30--60 m diameter polyacrylamide gel cylinders under a layer of vaseline oil.

[Study of evolutionary changes in subfraction composition of histone H1 in birds].

Analysis of electrophoretic mobility of histone H1 subfractions from liver, brain and erythrocytes of 41 bird species was carried out. Subfractions of erythrocyte H1 histones from each species were compared with those of thrush Turdus musicus. The majority of species proved to possess a set of electrophoretically similar subfractions.