Characterization of different chromatin types in “Mytilus galloprovincialis” L. after C-banding, fluorochrome and restriction endonuclease treatments

[Abstract]: In this study, we have carried out the cytogenetical characterization of “Mytilus galloprovincialis” L. (2n = 28) using conventional staining and banding techniques such as fluorochromes and restriction endonucleases treatment. Chromosome digestion with trypsin enzyme resulted in a G-banding pattern which allowed us to clearly identify and classify the chromosome pairs of “M. galloprovincialis”. C-banding and chromomycin A3 staining confirmed the existence of small amounts of constitutive heterochromatin. The treatment of samples with AluI, HaeIII, DpnI, MspI, HpaII and HinfI restriction endonucleases produced specific banding patterns which demonstrate the potential of endonucleases for chromosome banding in mussels. The results obtained allow us to describe six different types of chromatin in “M. galloprovincialis”. The type is determined by the response of the chromosomes to the different treatments. Differential digestion by the enzyme pair HpaII-MspI of specific C-band positive heterochromatic areas in some of the chromosomes suggests the presence of methylation.Ministerio de Educación y Ciencia; 88/0499MInisterio de Educación y Ciencia; 90/032

Chromosome differences between European mussel populations (genus “Mytilus”)

[Abstract]: We have analysed different populations of European mussels belonging to genus “Mytilus” in order to clarify the karyotype complements of these three species (“M. edulis”, “M. galloprovincialis” and “M. trossulus”). We have employed different cytogenetic techniques (C-banding, fluorochrome staining and Ag-NOR staining) and we have carried out chromosome measurements by using image analysis. Results obtained allow us to confirm the diploid number of these species and to detect different karyotype composition. Furthermore, we describe cytogenetical differences between larval chromosomes and gill tissue chromosomes.Xunta de Galicia; 10303B9

Chromosomal markers in three species of the genus “Mytilus” (Mollusca: Bivalvia)

[Abstract]: The analysis of C-banding, NOR and fluorochrome staining was carried out in three species of European mussel, "Mytilus edulis", "M. galloprovincialis" and "M. trossulus". The results obtained allow us to detect changes in the constitutive heterochromatin within the genus "Mytilus". The existences of chromosomal markers permit us to identify and distinguish, at the cytogenetical level, these three types of mussel.MInisterio de Educación y Ciencia; 90/032

Grandes accionistas y costes de agencia de la deuda. El caso español

This paper analyses the influence of large controlling shareholders on the terms of bank loans for a sample of 984 loans to 261 non-financial Spanish public and private firms over the period 2001-2017. The results show that the presence of large controlling shareholders increases the interest rate spread of bank loans only in public firms, whereas the influence is insignificant for private firms. Similarly, a less evenly balanced distribution of ownership among large shareholders is associated with higher loan spreads for public firms. Our results reveal that large controlling shareholders expropriate wealth from other investors in public firms, in line with the existence of lower benefits for borrowers due to having large controlling shareholders when they have other internal and external mechanisms of control.El objetivo del presente trabajo consiste en analizar la influencia que los grandes accionistas tienen sobre las condiciones de los préstamos bancarios para una muestra compuesta por 984 préstamos realizados a 261 empresas cotizadas y no cotizadas españolas no financieras durante el periodo 2001-2017. Los resultados muestran que la presencia de grandes accionistas incrementa el tipo de interés pagado por los préstamos en el caso de las empresas cotizadas, mientras el efecto no es significativo para las empresas no cotizadas. De forma similar, una distribución de la propiedad menos equilibrada entre los grandes accionistas está asociada con un mayor tipo de interés pagado por las empresas cotizadas. Los resultados ponen de manifiesto que los grandes accionistas expropian riqueza de otros inversores en las empresas cotizadas, en línea con la existencia de menores beneficios para los prestatarios de la existencia de grandes accionistas cuando disponen de otros mecanismos, tanto internos como externos, de control

Selective Reagent Ion Mass Spectrometric Investigations of the Nitroanilines

This paper presents an investigation of proton and charge transfer reactions to 2-, 3- and 4-nitroanilines (C6H6N2O2) involving the reagent ions H3O+·(H2O)n (n=0, 1 and 2) and O2+, respectively, as a function of reduced electric field (60-240 Td), using Selective Reagent Ion-Time-of-Flight-Mass Spectrometry (SRI-ToF-MS). To aid in the interpretation of the H3O+·(H2O)n experimental data, the proton affinities and gas-phase basicities for the three nitroaniline isomers have been determined using density functional theory. These calculations show that proton transfer from both the H3O+ and H3O+·H2O reagent ions to the nitroanilines will be exoergic and hence efficient, with the reactions proceeding at the collisional rate. For proton transfer from H3O+ to the NO2 sites, the exoergicities are 171 kJ mol-1 (1.8 eV), 147 kJ mol-1 (1.5 eV) and 194 kJ mol-1 (2.0 eV) for 2-, 3- and 4-nitroanilines, respectively. Electron transfer from all three of the nitroanilines is also significantly exothermic by approximately 4 eV. Although a substantial transfer of energy occurs during the ion/molecule reactions, the processes are found to predominantly proceed via non-dissociative pathways over a large reduced electric field range. Only at relatively high reduced electric fields (>180 Td) is dissociative proton and charge transfer observed. Differences in fragment product ions and their intensities provide a means to distinguish the isomers, with proton transfer distinguishing 2-nitroaniline (2-NA) from 3- and 4-NA, and charge transfer distinguishing 4-NA from 2- and 3-NA, thereby providing a means to enhance selectivity using SRI-ToF-MS.(VLID)4826158Version of recor