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We investigated the role of socioeconomic status (SES) in the unfolding of vocabulary and text-comprehension skills in language minority bilingual children, who are educated exclusively in their L2. For comparison, a monolingual control group was also tested, consisting of children of the same age and schooling. We administered a synonyms task to measure vocabulary and an inference test to measure reading comprehension. Socioeconomic status scores were obtained through the Hollingshead Four Factor Index questionnaire. Our results showed that being bilingual did not influence vocabulary and text-comprehension skills in the age group being tested (9-11 years). Whereas, SES played a significant role in relation to age and schooling. Interestingly, two different mediation analyses demonstrated that vocabulary knowledge accounted for a significant portion of the causal relationship between SES and reading comprehension, and that reading comprehension itself can explain part of the relationship between SES and vocabulary. The social and educational implications of the findings are discussed.

The syntheses and X-ray crystal structures of six new self-assembled supramolecular As and Sb-containing cryptands are described. Analysis in the context of previously reported As2L3and Sb2L3cryptands reveals that small differences in ligand geometries result in significant differences in the helicity of the complexes and the stereochemistry of the metal coordination within the assembled complexes. Additionally, a new synthetic route is described which involves exposure of reactants to vacuum to help facilitate self-assembly. [ABSTRACT FROM AUTHOR]

The reaction of AsCl3 with H2L (where L = a rigid dithiolate) results in the self-assembly of As2L2Cl2 supramolecular macrocycles. For ligands 4,4′-bis(mercaptomethyl)biphenyl (H21), 4,4′-bis(mercaptomethyl)-trans-stilbene (H22), and 1,4-dimethoxy-2,5-bis(mercaptomethyl)benzene (H23), the macrocyclic cavities of the resulting assemblies are large enough to host aromatic solvent molecules, as revealed by single crystal X-ray structures of the inclusion complexes. As2L2Cl2 macrocycles form in solution as a mixture of diastereomers, but the diastereomers can be selectively crystallized and separated. Crystallization of syn- or anti-As232Cl2 can be controlled using host–guest interactions by the prudent choice of crystallization solvents. anti-As232Cl2 crystallizes exclusively from chloroform and benzene, while a [(syn-As232Cl2)2·p-xylene] dimer crystallizes from p-xylene and a mixture of [(syn-As232Cl2)(anti-As232Cl2)·toluene] and [(syn-As232Cl2)2·toluene] dimers crystallize from toluene. [ABSTRACT FROM AUTHOR]

Treatment of 1,4-bis(2-mercaptoethyl)benzene (1) or 1,4-bis(2-bromoethyl)benzene (2) with excess SbCl3affords new one-dimensional and two-dimensional supramolecular coordination networks. Compound 1·2SbCl3is stabilized solely by Sb···Cl, Sb-π, and Sb···S secondary bonding interactions (SBIs), providing an unusual example of Sb(III) and a thiol interacting through an SBI rather than a strong antimony thiolate bond. 2·2SbCl3is stabilized by Sb···Cl, Sb···Br, and Sb-π SBIs. Both compounds have higher melting points than that of SbCl3. The crystal structures of 1·2SbCl3and 2·2SbCl3have been determined by single crystal X-ray diffraction methods. [ABSTRACT FROM AUTHOR]