A study of planar chromophores in dichromophoric molecules by circular dichroism spectroscopy

A synthesis of a series of enantiomerically pure polycyclic structures derived from (+)-(1S,5S)-bicyclo[3.3.1]nonane-2,6-dione was accomplished. Molecules containing single or two similar or different chromophores were obtained. Chiroptical properties of the synthesized chiral structures 2-5, and 7 having carbonyl, 1,2-methylenedioxybenzene, and indole chromophores were studied. The sign of the cotton effect was related to sector rules and the orientation of the planes containing chromophores in dichromophoric molecules possessing 1,2-methylenedioxybenzene and carbonyl or indole chromophores. Interaction of the chromophores in dichromophoric molecules was examined by CD spectroscopy; however, no direct evidence was obtained.     

<Emphasis Type="Italic">In vitro</Emphasis> culture of <Emphasis Type="Italic">Chrysanthemum</Emphasis> plantlets using light-emitting diodes

Effects of illumination spectrum on the morphogenesis of chrysanthemum plantlets (Chrysanthemum morifolium Ramat. ‘Ellen’) grown in vitro were studied using an illumination system consisting of four groups of light-emitting diodes (LEDs) in the following spectral regions: blue (450nm), red (640nm), red (660nm), and far-red (735nm). Taking into account all differences in shoot height, root length, and fresh and dry weight (FW and DW, respectively), observed while changing the total photon flux density (PFD), the optimal total PFD for growth of chrysanthemum plantlets in vitro was estimated. For 16 h photoperiod and typical fractions of the spectral components (14%, 50%, 28%, and 8%, respectively), the optimal total PFD was found to be 40 μmol m⁻² s⁻¹. Our study shows that the blue component in the illumination spectrum inhibits the plantlet extension and formation of roots and simultaneously increases the DW to FW ratio and content of photosynthetic pigments. We demonstrate photomorphogenetic effects in the blue region and its interaction with the fractional PFD of the far-red spectral component. Under constant fractional PFD of the blue component, the root number, length of roots and stems, and fresh weight of the plantlets have a correlated nonmonotonous dependence on the fractional PFD of the far-red component.     

Synthesis of human parainfluenza virus 4 nucleocapsid-like particles in yeast and their use for detection of virus-specific antibodies in human serum

Applied Microbiology and Biotechnology - The aim of this study was to produce human parainfluenza virus type 4 (HPIV4) nucleocapsid (N) protein in yeast Saccharomyces cerevisiae expression system,...     

Human-mediated lineage admixture in an expanding Ponto-Caspian crustacean species <Emphasis Type="Italic">Paramysis lacustris</Emphasis> created a novel genetic stock that now occupies European waters

Identifying the origins and colonization routes of alien species is critical to understanding the mechanisms, consequences and management of invasions. This study aims to demonstrate and explain conflicting genetic signals in a widespread invasive Ponto-Caspian mysid Paramysis lacustris using mitochondrial DNA and microsatellite markers. Native Black Sea populations of P. lacustris are divided into three distinct phylogeographic groups: Danube–Dniester region, coastal Danube lakes, and Dnieper River delta. In the 1950s–1970s the species has been extensively used for relatively well documented transplantations in Eastern Europe. However, the populations in the newly established distribution area do not match any of the known native groups, and their genetic signal does not correspond with the recorded transplantation history. Using Bayesian Approximate Computation we explore alternative scenarios that could explain the unexpected mitochondrial and nuclear signals in the introduced populations. We suggest that reservoir construction and break-up of natural dispersal barriers on the River Dnieper have brought about a novel stock, probably admixed from a previously isolated and unknown “relict” population in the middle Dnieper and the genetically distinct Dnieper delta lineage. Through further intentional transfers this new P. lacustris lineage is now widely present in Eastern Europe and is likely to have new gene and trait combinations. The conflicting mitochondrial-nuclear signal in non-native populations also highlights the importance of using multiple genetic markers when tracing invasion sources and pathways.     

Records of bees (Hymenoptera: Apoidea) new to both Georgia and Transcaucasia revealed by DNA barcoding

Community composition of local pollinator assemblages, population dynamics and distribution patterns of many species are still poorly known, especially in little studied regions like Transcaucasia. We generated a total of 189 DNA barcodes from bees collected in 14 apple orchards in central and eastern Georgia to extend our knowledge of their distribution. Sequences (ca. 700 bp of the mitochondrial cytochrome oxidase I gene) were compared to the NCBI nucleotide database. Using a threshold of 98% similarity, analyses suggested that the sampled bees belong to 36 species of Apidae, Andrenidae, Halictidae, and Megachilidae. We report five bee species for the first time for Georgia: Andrena alfkenella Perkins, 1914, Halictus cochlearitarsis Dours, 1871, Nomada goodeniana (Kirby, 1802), Nomada ruficornis (Linnaeus, 1758) and Eucera nigrescens Pérez, 1879, four of which are also new for the Transcaucasia region. With these additions, the number of bee species known to occur in Georgia increases to 371.     

Semi-Supervised Morphosyntactic Classification of Old Icelandic

We present IceMorph, a semi-supervised morphosyntactic analyzer of Old Icelandic. In addition to machine-read corpora and dictionaries, it applies a small set of declension prototypes to map corpus words to dictionary entries. A web-based GUI allows expert users to modify and augment data through an online process. A machine learning module incorporates prototype data, edit-distance metrics, and expert feedback to continuously update part-of-speech and morphosyntactic classification. An advantage of the analyzer is its ability to achieve competitive classification accuracy with minimum training data.