953 resultados para Braking in a Turn.


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We have previously shown that the TolA protein is required for the correct surface expression of the Escherichia coli O7 antigen lipopolysaccharide (LPS). In this work, delta tolA and delta pal mutants of E. coli K-12 W3110 were transformed with pMF19 (encoding a rhamnosyltransferase that reconstitutes the expression of O16-specific LPS), pWQ5 (encoding the Klebsiella pneumoniae O1 LPS gene cluster), or pWQ802 (encoding the genes necessary for the synthesis of Salmonella enterica O:54). Both DeltatolA and delta pal mutants exhibited reduced surface expression of O16 LPS as compared to parental W3110, but no significant differences were observed in the expression of K. pneumoniae O1 LPS and S. enterica O:54 LPS. Therefore, TolA and Pal are required for the correct surface expression of O antigens that are assembled in a wzy (polymerase)-dependent manner (like those of E. coli O7 and O16) but not for O antigens assembled by wzy-independent pathways (like K. pneumoniae O1 and S. enterica O:54). Furthermore, we show that the reduced surface expression of O16 LPS in delta tolA and delta pal mutants was associated with a partial defect in O-antigen polymerization and it was corrected by complementation with intact tolA and pal genes, respectively. Using derivatives of W3110 delta tolA and W3110 delta pal containing lacZ reporter fusions to fkpA and degP, we also demonstrate that the RpoE-mediated extracytoplasmic stress response is upregulated in these mutants. Moreover, an altered O16 polymerization was also detected under conditions that stimulate RpoE-mediated extracytoplasmic stress responses in tol+ and pal+ genetic backgrounds. A Wzy derivative with an epitope tag at the C-terminal end of the protein was stable in all the mutants, ruling out stress-mediated proteolysis of Wzy. We conclude that the absence of TolA and Pal elicits a sustained extracytoplasmic stress response that in turn reduces O-antigen polymerization but does not affect the stability of the Wzy O-antigen polymerase.

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Topic Background: Peace education initiatives in schools are often based on social psychological theories assuming that social identity affects ingroup and outgroup attitudes and, in turn, behaviors relating to relevant outgroups. However, research evidence on the role of children's social identity has often failed to take account of different social identity dimensions or to conceptualise behavior in the context of children's understandings of the social world. While recent research relating to bullying and bystander behavior amongst children has addressed the latter point, this has rarely been considered in conjunction with a differentiated view of social identity. This paper is therefore distinctive as it will address the role of social identity dimensions with regards to reported behavior as captured in bystander scenarios relating to outgroup derogation. This is particularly important in the context of divided societies, where peace education initiatives are crucial in promoting positive community relations for the future and where such initiative may be hampered by communities' concerns about loss of identity. In the context of Northern Ireland, a divided society emerging from conflict, social identity, outgroup attitudes and behaviours have been key concepts addressed by peace educators
for many years.

Research questions: This paper therefore set out to investigate the relationship between social identity, measured as affiliation with the group and exploration of its meaning for the child, sectarian attitudes and pupils' reported willingness to challenge sectarian bullying in their school environment in Northern Ireland.
Research methods: The findings are based on the analysis of a baseline survey, which forms part of a randomised control trial of an intervention aimed at promoting community relations and reconciliation. The trial includes 35 primary and post-primary schools and about 800 pupils from 8-11 years old who completed an online questionnaire at the start of the programme. Main instruments for this study included adapted scales measuring identity affiliation and identity exploration, sectarian attitudes and scenarios capturing pupils' intentions in bystander situations relating to sectarian bullying.

Analytical framework: Results are analysed using regression analysis and additionally investigate gender and religious differences.

Research findings and/or contribution to knowledge: Results are discussed in the light of the role of social identity dimensions and their relationship to outgroup attitudes and willingness to challenge outgroup derogation. The paper concludes with potential implications for peace education initiatives in Northern Ireland and beyond.

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Peace education initiatives in schools are often based on social psychological theories assuming that social identity affects ingroup and outgroup attitudes and, in turn, behaviors relating to relevant outgroups. However, research evidence on the role of young people’s social identity has often failed to take account of different social identity dimensions or to conceptualise outgroup behavior in the context of young people’s understandings of the social world. While recent research relating to bullying and bystander behavior amongst young people has addressed the latter point, this has rarely been considered in conjunction with a differentiated view of social identity. This paper is therefore distinctive as it will address the role of social identity dimensions with regards to behavior as captured in bystander scenarios relating to intergroup discrimination. This is particularly important in the context of divided societies, where peace education initiatives are crucial in promoting positive community relations for the future and where such initiative may be hampered by communities’ concerns about loss of identity and hardened intergroup attitudes. Furthermore, previous research frequently highlighted teachers’ fears to tackle outgroup attitudes in the classroom, especially in contexts where pupils and the wider school community are seen as entrenched in community divisions (Hughes, Donnelly, Hewstone, Gallagher & Carlisle, 2010). However, there is no research investigating the relationship between pupils’ attitudes and teacher confidence to talk about such issues in the classroom, which is explored in this paper.

In the context of Northern Ireland, a divided society emerging from sectarian conflict, social identity, outgroup attitudes and outgroup behaviours have been key concepts addressed by peace educators for many years. Building on this work, this paper provides a detailed picture of young people’s strength of group identification and their willingness to explore ingroup perspectives, sectarian attitudes and their reported willingness to challenge sectarian bullying. Using data from a baseline survey, which forms part of a randomized control trial investigating the effect of an educational intervention aimed to promote reconciliation, the sample involved young people of different denominational backgrounds, attending separate school sectors. The baseline data will be used to compare with post intervention data. Therefore, the data and its findings would be of particular interest to educators and policy makers in other European countries who are working to develop peace education interventions in societies emerging from conflict. Additionally, this paper considers the results from a baseline teacher survey, collected before training and teaching of the intervention began. The teacher survey focused on confidence in tackling sectarian issues in the classroom, previous experience of teaching such issues and their hopes and concerns for the reconciliation intervention.

This paper therefore set out to investigate the relationship between dimensional concept of social identity, sectarian attitudes and pupils’ reported willingness to challenge sectarian bullying and to compare this with their teachers’ attitudes to teaching about sectarian issues in the classroom.



Method

The pupil sample included 35 primary and post-primary schools and about 800 pupils from 8-11 years old who completed an online questionnaire in December 2011 and January 2012. Main instruments for young people’s survey included an adapted version of the Multi-ethnic identity measure (Phinney, 1992) incorporating the dimensions identity affirmation and exploration, outgroup attitude scales, including an adaptation of the social distance measure (Bogardus, 1947), as well as a measure adapted from Palmer and Cameron (2011) involving scenarios to capture pupils’ intentions in bystander situations relating to intergroup discrimination. Results are analysed using regression analysis and take account of potential gender and religious differences. The teacher questionnaire was completed by the 35 primary and post-primary teachers who will deliver the intervention. Results are analysed in terms of how teachers’ responses compare with their pupil attitudes by considering their confidence in tackling sectarian issues in the classroom and how their previous experience and training relate to their hopes and concerns for the intervention.


Expected Outcomes

Results from the young people’s survey are discussed in the light of the role of social identity dimensions and their relationship to sectarian attitudes and reported bystander behaviour in sectarian school incidents. Furthermore, results related to pupils’ sectarian attitudes will be compared with teachers’ reported confidence in tackling sectarianism in the classroom. The teacher questionnaire also presents interesting findings in relation to teachers’ previous training and experience and how this may influence different perspectives on peace and reconciliation interventions and their expectations of what these could achieve. The paper concludes with potential implications for peace education initiatives and related teacher training in Northern Ireland and beyond. The implications will be of particular interest to policy makers, educators and those working in the area of peace education to design and implement interventions.


References

Bogardus, E. S. (1947) Measurement of Personal-Group Relations. Sociometry, 10: 4: 306–311. Hughes, J., Donnelly, C., Hewstone, M., Gallagher, T. & Carlisle, K. (2010) School partnerships and reconciliation: An evaluation of school collaboration in Northern Ireland. Belfast: Queen’s University Belfast. Available online: http://www.schoolsworkingtogether.com/documents/School%20collaboration%20in%20NI%202010.pdf. (accessed 27th Jan 2010) Palmer, S. & Cameron, L. (2011, May). What are the moderators and mediators of children’s bystander behaviour in the context of intergroup discrimination? Paper session presented at the UNA Global Biennial Conference 2011: Building Peaceable Communities: The Power of Early Childhood, Amsterdam, Holland. Phinney, J. S. (1992). The Multigroup Ethnic Identity Measure: A new scale for use with diverse groups. Journal of Adolescent Research, 7, 156–176.

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The Self Categorization approach to national leadership proposes that leaders rhetorically construct national identity as essentialized and inevitable in order to consensualize and mobilize the population. In contrast, discursive studies have demonstrated how national politicians flexibly construct the nation to manage their own accountability in local interactions, though this in turn has neglected broader leadership processes. The present paper brings both approaches together to examine how and when national politicians construct versions of national identity in order to account for their failure as well as success in mobilizing the electorate. Eight semi-structured conversational style interviews were conducted with a strategic sample of eight leading Irish politicians on the subject of the 2008/2009 Irish Lisbon Treaty referenda. Using a Critical Discourse Psychology approach, the hegemonic repertoire of the ‘settled will’
of the informed and consensualized Irish nation was identified across all interviews. Politicians either endorsed the ‘settled will’ repertoire as evidence of their successful leadership, or rejected the repertoire by denying the rationality or unity of the populace to account for their failure. Our results suggest national identity is only constructed as essentialized and inevitable to the extent that it serves a strategic political purpose.

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The mid-Holocene decline of Tsuga canadensis (hereafter Tsuga) populations across eastern North America is widely perceived as a synchronous event, driven by pests/pathogens, rapid climate change, or both. Pattern identification and causal attribution are hampered by low stratigraphic density of pollen-sampling and radiometric dates at most sites, and by absence of highly resolved, paired pollen and paleoclimate records from single sediment cores, where chronological order of climatic and vegetational changes can be assessed. We present an intensely sampled (contiguous 1-cm intervals) record of pollen and water table depth (inferred from testate amoebae) from a single core spanning the Tsuga decline at Irwin Smith Bog in Lower Michigan, with high-precision chronology. We also present an intensively sampled pollen record from Tower Lake in Upper Michigan. Both sites show high-magnitude fluctuations in Tsuga pollen percentages during the pre-decline maximum. The terminal decline is dated at both sites ca. 5000 cal yr BP, some 400 years later than estimates from other sites and data compilations. The terminal Tsuga decline was evidently heterochronous across its range. A transient decline ca. 5350 cal yr BP at both sites may correspond to the terminal decline at other sites in eastern North America. At Irwin Smith Bog, the terminal Tsuga decline preceded an abrupt and persistent decline in water table depths by;200 years, suggesting the decline was not directly driven by abrupt climate change. The Tsuga decline may best be viewed as comprising at least three phases: a long-duration predecline maximum with high-magnitude and high-frequency fluctuations, followed by a terminal decline at individual sites, followed in turn by two millennia of persistently low Tsuga populations. These phases may not be causally linked, and may represent dynamics taking place at multiple temporal and spatial scales. Further progress toward understanding the phenomenon requires an expanded network of high-resolution pollen and paleoclimate chronologies.

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Thie examines the continuing role that the landed class enjoyed in Northern Ireland in contrast to the experience of their fellow landlords in the rest of Ireland following Partition. It argues that the senses of tradition and continuity which the unionist population in particular attributed to the old landed elite gave them an important role in bolstering the newly created state of Northern Ireland. In turn this allowed them to continue acting as a social elite long after the economic and political foundations of their ascendancy had been removed.

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The two environmental management system (EMS) standards EMAS and ISO 14001 have been available in Europe for the last 15 years. ISO 14001 has been taken up at a much larger scale but many firms in the German automotive and engineering industry have certified their EMSs according to both standards. Two research questions are addressed: (i) What explains why companies adopt both EMAS and ISO 14001? (ii) Are EMAS and ISO 14001 complements or substitutes? Based on 21 interviews with industrial and institutional representatives, this study finds that, first, the two standards are adopted for completely different reasons: while ISO 14001 is often done as a response to external pressure, EMAS tends to be motivated internally. Second, it is argued that EMAS and ISO 14001 are likely in a situation of direct competition at present which may well turn into complementarity in the future.

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The seminal work of Lipset and Rokkan, which explores how party systems evolved organically from nineteenth-century roots, has generally been applied in states which have enjoyed a long-standing territorial identity. Their model's emphasis on stability and predictability can, however, be reconciled with circumstances where the very identity of the state itself is an issue. This article explores the capacity of the model to explain party divisions in three nested contexts: the pre-1922 United Kingdom, which encountered problems with its Celtic peripheries, and especially with Ireland; independent Ireland, where a unique party system developed, largely in response to a broader historical and geographical context; and Northern Ireland, where party politics fossilised in the 1880s, and began to unfreeze only in the 1970s. The article argues that the Lipset–Rokkan model casts valuable light on these processes, which in turn contribute to the theoretical richness of the model.