We propose a new transition state for oxygen in silica. This state is produced by the insertion of an oxygen molecule into the Si − O − Si bond, i.e. it consists of producing a Si−O−O−O−Si bond. This state allows molecular oxygen diffusion in silica without breaking the molecular O2 bond and it is energetically more stable than a peroxy configuration. This configuration may allow for exchange o...

There is growing interest in compounds containing functionalized E=E multiple bonds (E=Si, Ge, Sn, Pb) because of their potential to exhibit novel physical and chemical properties. However, compounds containing multiple functionalizations are rare, with scarcity increasing with increasing degree of substitution. The first ditetrelene R2 E=ER2 in which the E=E bond is substituted by four heteroa...

Tremendous progress has been made in identifying genes involved in pigmentation in dogs in the past few years. Comparative genomics has both aided and benefited from these findings. Seven genes that cause specific coat colours and/or patterns in dogs have been identified: melanocortin 1 receptor, tyrosinase related protein 1, agouti signal peptide, melanophilin, SILV (formerly PMEL17), micropht...

The SILVER locus has been mapped in the domestic cat, identifying a unique genomic location distinct from that of any known reported gene associated with silver or hypopigmentation in mammals. A demonstrated lack of linkage to SILV, the strong candidate gene for silver, led to the initiation of a genome scan utilizing 2 pedigrees segregating for silver coat color. Linkage mapping defined a geno...

W ith 400 recognized breeds worldwide and a recently completed draft genomic sequence, the dog has emerged as a model organism of choice for the genetic dissection of morphological traits and diseases (1–3). Of great interest is the fact that a number of disorders in purebred dogs are also of human medical relevance (1, 2). In this context, the study by Clark et al. (4) in this issue of PNAS is...

0306-4573/$ see front matter 2009 Elsevier Ltd doi:10.1016/j.ipm.2009.09.003 * Corresponding author. Tel.: +55 92 3647 4019. E-mail addresses: [email protected] (M.R. H edu.br (T.P. Silva), [email protected] (A.S. da Silv Queries submitted to search engines can be classified according to the user goals into three distinct categories: navigational, informational, and transactional. Such cla...

0167-8191/$ see front matter 2008 Elsevier B.V doi:10.1016/j.parco.2008.09.013 * Corresponding author. Tel.: +351 217 500 244; E-mail address: [email protected] (F.A.B. da Silv 1 In this paper, we use the terms ‘‘Bag-of-Tasks” a Bag-of-Tasks applications are parallel applications composed of independent tasks. Examples of Bag-of-Tasks (BoT) applications include Monte Carlo simulations, massi...

BACKGROUND Deafness in dogs is frequently associated with the pigment genes piebald and merle. Little is known about the prevalence of deafness in dogs carrying the merle allele. OBJECTIVE To determine the prevalence of deafness in dogs heterozygous and homozygous for the merle allele of the mouse Silver pigment locus homolog (SILV) gene. ANIMALS One hundred and fifty-three privately owned ...