Comparison of metal ion-induced conformational changes in parvalbumin and oncomodulin as probed by the intrinsic fluorescence of tryptophan 102.

The calcium-induced conformational changes of the 108-amino acid residue proteins, cod III parvalbumin and oncomodulin, were compared using tryptophan as a sensitive spectroscopic probe. As native oncomodulin is devoid of tryptophan, site-specific mutagenesis was performed to create a mutant protein in which tryptophan was placed in the identical position (residue 102) as the single tryptophan residue in cod III parvalbumin. The results showed that in the region probed by tryptophan-102, cod III parvalbumin experienced significantly greater changes in conformation upon decalcification compared to the oncomodulin mutant, F102W. Addition of 1 eq of Ca2+ produced greater than 90% of the total fluorescence response in F102W, while in cod III parvalbumin, only 74% of the total was observed. Cod III parvalbumin displayed a negligible response upon Mg2+ addition. In contrast, F102W did respond to Mg2+, but the response was considerably less when compared to Ca2+ addition. Time-resolved fluorescence showed that the tryptophan in both proteins existed in at least two conformational states in the presence of Ca2+ and at least three conformational states in its absence. Comparison with quantum yield measurements indicated that the local electronic environment of the tryptophan was significantly different in the two proteins. Collectively, these results demonstrate that both cod III parvalbumin and oncomodulin undergo Ca2(+)-specific conformational changes. However, oncomodulin is distinct from cod III parvalbumin in terms of the electronic environment of the hydrophobic core, the magnitude of the Ca2(+)-induced conformational changes, and the number of calcium ions required to modulate the major conformational changes

Increases in salience of ethnic identity at work: the roles of ethnic assignation and ethnic identification

To better understand how ethnicity is actually experienced within organisations, we examined reported increases in ethnic identity salience at work and responses to such increases. Thirty British black Caribbean graduate employees were interviewed about how and when they experienced their ethnic identity at work. The findings demonstrated that increased salience in ethnic identity was experienced in two key ways: through ‘ethnic assignation’ (a ‘push’ towards ethnic identity) and ‘ethnic identification’ (a ‘pull’ towards ethnic identity). We explore how and when ethnic assignation and ethnic identification occur at work, and their relevance to how workplaces are experienced by this group of minority ethnic employees. The findings suggest the need for further research attention to the dynamic and episodic nature of social identity, including ethnic identity, within organisations, and to the impact of such increases in salience of social identities on behaviour at work

Identity threat and identity multiplicity among minority youth: Longitudinal relations of perceived discrimination with ethnic, religious, and national identification in Germany

The notion that ethnic and religious minority identities are inherently incompatible with the national identities of European immigrant‐receiving societies is popular in public discourse. Although findings documenting such negative associations seemingly support this claim, other research shows that the intergroup context matters for the extent to which minorities’ ethnic and religious identities are conflicting (i.e., negatively associated) or compatible (i.e., positively associated) with European national identities. However, previous research relied on cross‐sectional data and therefore could not capture the dynamic process through which minority youth come to develop compatible or conflicting identification patterns. We extend this work with a longitudinal approach by capturing developmental trajectories of identity multiplicity among ethnic minority early adolescents in Germany over three waves with 9‐month intervals. At each measurement point, participants reported their ethnic, religious, and (German) national identification and their experiences with discriminatory treatment. We estimate a cross‐lagged panel model to study how identification relates to perceived discrimination and how this affects (changes in) associations between ethnic, religious, and national identification of minority youth. Our results show prevalent positive associations between ethnic, religious, and national identification across minority youth in the sample. Those who report more frequent discrimination, however, lower their (German) national identification over time, which in turn predicts increased minority identification. We conclude that identity threat indeed triggers a development of more conflicting identification patterns

People of the British Isles: preliminary analysis of genotypes and surnames in a UK control population

There is a great deal of interest in fine scale population structure in the UK, both as a signature of historical immigration events and because of the effect population structure may have on disease association studies. Although population structure appears to have a minor impact on the current generation of genome-wide association studies, it is likely to play a significant part in the next generation of studies designed to search for rare variants. A powerful way of detecting such structure is to control and document carefully the provenance of the samples involved. Here we describe the collection of a cohort of rural UK samples (The People of the British Isles), aimed at providing a well-characterised UK control population that can be used as a resource by the research community as well as providing fine scale genetic information on the British population. So far, some 4,000 samples have been collected, the majority of which fit the criteria of coming from a rural area and having all four grandparents from approximately the same area. Analysis of the first 3,865 samples that have been geocoded indicates that 75% have a mean distance between grandparental places of birth of 37.3km, and that about 70% of grandparental places of birth can be classed as rural. Preliminary genotyping of 1,057 samples demonstrates the value of these samples for investigating fine scale population structure within the UK, and shows how this can be enhanced by the use of surnames

Delineating ethnic and religious identities in research with British South Asians

The present essay presents a rationale for delineating ethnic and religious identities in empirical research into self-identification among British South Asians. It is argued that the delineation of these identities is important in order to (i) predict and explain the identificatory possibilities available to these individuals; (ii) explore the differential values attributed to these identities; (iii) the level of psychological 'connectedness' between the identities; and (iv) the inter-relations between these identities, particularly in relation to psychological coherence. It is argued that a systematic delineation of these identities may have favourable theoretical, empirical and practical outcomes