University of Oviedo

About: University of Oviedo is a education organization based out in Oviedo, Spain. It is known for research contribution in the topics: Population & Catalysis. The organization has 13423 authors who have published 31649 publications receiving 844799 citations. The organization is also known as: Universidá d'Uviéu & Universidad de Oviedo.

Sex chromosome linkage of 5S rDNA in rainbow trout (Oncorhynchus mykiss)

Abstract: The karyotype of the rainbow trout is characterized by a primitive XX/XY sex-determining chromosomal system. (Thorgaard et al., 1977). In the present study using FISH we have physically linked the 5S rRNA genes to the partially undifferentiated X chromosome pair. PCR amplified 5S rDNA was used for FISH and hybridization signals indicated that the genes were duplicated, present in one acrocentric and one metacentric pair of chromosomes. After analyzing several individuals, the female metaphases showed four fluorescent signals whereas males presented only three signals. Two of the three signals obtained in males corresponded to the metacentric pair whereas the single signal was mapped to the heterochromatin that cytologically differentiates the X chromosome from the Y chromosome. Double FISH experiments demonstrated that the 5S rDNA which is not sex linked is located at the NOR bearing arm close to the major ribosomal RNA genes (5.8S, 18S and 28S), similar to the situation observed in Atlantic salmon (Pendas et al., 1994a).

Depth Profile of Uncompensated Spins in an Exchange Bias System

Abstract: We have used the unique spatial sensitivity of polarized neutron and soft x-ray beams in reflection geometry to measure the depth dependence of magnetization across the interface between a ferromagnet and an antiferromagnet. The net uncompensated magnetization near the interface responds to applied field, while uncompensated spins in the antiferromagnet bulk are pinned, thus providing a means to establish exchange bias.

Bis(allyl)--Ruthenium(IV) Complexes as Highly Efficient Catalysts for the Redox Isomerization of Allylic Alcohols into Carbonyl Compounds in Organic and Aqueous Media: Scope, Limitations, and Theoretical Analysis of the Mechanism

Abstract: The catalytic activity of the bis(allyl)−ruthenium(IV) dimer [{Ru(η3:η3-C10H16)(μ-Cl)Cl}2] (C10H16 = 2,7-dimethylocta-2,6-diene-1,8-diyl) (1), and that of its mononuclear derivatives [Ru(η3:η3-C10H16)Cl2(L)] (L = CO, PR3, CNR, NCR) (2) and [Ru(η3:η3-C10H16)Cl(NCMe)2][SbF6] (3), in the redox isomerization of allylic alcohols into carbonyl compounds, both in tetrahydrofuran and in water, is reported. In particular, a variety of allylic alcohols have been quantitatively isomerized using [{Ru(η3:η3-C10H16)(μ-Cl)Cl}2] (1) as catalyst, the reactions proceeding in all cases faster in water. Remarkably, complex 1 has been found to be the most efficient catalyst reported to date for this particular transformation, leading to TOF and TON values up to 62 500 h-1 and 1 500 000, respectively. Moreover, catalyst 1 can be recycled and is capable of performing allylic alcohol isomerizations even in the presence of conjugated dienes, which are known to be strong poisons in isomerization catalysis. On the basis of both exp...