Poly[[μ3-chlorido-bis(μ2-thio­urea-κS)disilver(I)] nitrate]

The mol­ecular structure of the title polymeric complex, {[Ag2Cl(CH4N2S)2]NO3}n, consists of a binuclear cationic complex and a nitrate counter-ion. The cationic complex contains two bridging thio­urea (Tu) ligands and a triply bridging μ3-Cl anion. The latter is probably released from 2-amino­ethane­thiol hydro­chloride during the synthesis. The coordination environment around the two AgI atoms is different; one is trigonal planar, being coordinated by two thio­urea ligands through the S atoms and to one Cl− ion, while in the other the AgI atom is tetra­hedrally coordinated by two thio­urea ligands through the S atoms and to two Cl− ions. These units aggregate through the Cl− anion and the Tu S atoms, forming a chain propagating in [100]. In the crystal structure, the polymeric chains are linked via N—H⋯O and N—H⋯Cl hydrogen bonds, forming a double layer two-dimensional network propagating in (011)

Multivariate moments expansion density: application of the dynamic equicorrelation model

In this study, we propose a new semi-nonparametric (SNP) density model for describing the density of portfolio returns. This distribution, which we refer to as the multivariate moments expansion (MME), admits any non-Gaussian (multivariate) distribution as its basis because it is specified directly in terms of the basis density’s moments. To obtain the expansion of the Gaussian density, the MME is a reformulation of the multivariate Gram-Charlier (MGC), but the MME is much simpler and tractable than the MGC when positive transformations are used to produce well-defined densities. As an empirical application, we extend the dynamic conditional equicorrelation (DECO) model to an SNP framework using the MME. The resulting model is parameterized in a feasible manner to admit two-stage consistent estimation and it represents the DECO as well as the salient non-Gaussian features of portfolio return distributions. The in- and out-of-sample performance of a MME-DECO model of a portfolio of 10 assets demonstrate that it can be a useful tool for risk management purposes

Psychiatric and cognitive phenotype in children and adolescents with myotonic dystrophy

Myotonic dystrophy type 1 (DM1) is the most frequent inherited neuromuscular disorder. The juvenile form has been associated with cognitive and psychiatric dysfunction, but the phenotype remains unclear. We reviewed the literature to examine the psychiatric phenotype of juvenile DM1 and performed an admixture analysis of the IQ distribution of our own patients, as we hypothesised a bimodal distribution. Two-thirds of the patients had at least one DSM-IV diagnosis, mainly attention deficit/ hyperactivity disorder and anxiety disorder. Two-thirds had learning disabilities comorbid with mental retardation on one hand, but also attention deficit, low cognitive speed and visual spatial impairment on the other. IQ showed a bi-modal distribution and was associated with parental transmission. The psychiatric phenotype in juvenile DM1 is complex. We distinguished two different phenotypic subtypes: one group characterised by mental retardation, severe developmental delay and maternal transmission; and another group characterised by borderline full scale IQ, subnormal development and paternal transmission