151 research outputs found

    From words to actions: assessing the impact of antiracist declarations in library and information science

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    Introduction. The aims of this paper are to reaffirm calls for the global elimination of racism in library and information science, to specify ways of making progress towards such elimination, and to indicate how to assess the extent to which the declarations made by international bodies have had an impact on the success of antiracist strategies in which library and information science professionals engage at the local level. Method. A review is undertaken of the declarations on racism made by the United Nations (UN), and by two professional organisations: the International Federation of Library Associations and Institutions (IFLA), and the International Society for Knowledge Organization (ISKO). A case study approach is then taken in identifying antiracist strategies in library and information science in the United States. Analysis. International declarations on racism are numerous and expansive, and are suggestive of several important categories of antiracist strategy. Results. A means of assessing the relationship between declarations and strategies is proposed. Conclusions. It is concluded that the impact of declarations has not been substantial. Affirmative action policies, hate speech bans, reparative taxonomies, and actions decentring whiteness are few and far between in library and information science. Renewed effort should be made to engage in antiracist strategies of the kinds promoted in the declarations

    Understanding and addressing mathematics anxiety using perspectives from education, psychology and neuroscience

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    Mathematics anxiety is a significant barrier to mathematical learning. In this article, we propose that state or on-task mathematics anxiety impacts on performance, while trait mathematics anxiety leads to the avoidance of courses and careers involving mathematics. We also demonstrate that integrating perspectives from education, psychology and neuroscience contributes to a greater understanding of mathematics anxiety in its state and trait forms. Research from cognitive psychology and neuroscience illustrates the effect of state mathematics anxiety on performance and research from cognitive, social and clinical psychology, and education can be used to conceptualise the origins of trait mathematics anxiety and its impact on avoidant behaviour. We also show that using this transdisciplinary framework to consider state and trait mathematics anxiety separately makes it possible to identify strategies to reduce the negative effects of mathematics anxiety. Implementation of these strategies among particularly vulnerable groups, such as pre-service teachers, could be beneficial

    Making mathematics and science integration happen: key aspects of practice

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    The integration of mathematics and science teaching and learning facilitates student learning, engagement, motivation, problem-solving, criticality and real-life application. However, the actual implementation of an integrative approach to the teaching and learning of both subjects at classroom level, with in-service teachers working collaboratively, at second-level education, is under-researched due to the complexities of school-based research. This study reports on a year-long case study on the implementation of an integrated unit of learning on distance, speed and time, within three second-level schools in Ireland. This study employed a qualitative approach and examined the key aspects of practice that impact on the integration of mathematics and science teaching and learning. We argue that teacher perspective, teacher knowledge of the ‘other subject’ and of technological pedagogical content knowledge (TPACK), and teacher collaboration and support all impact on the implementation of an integrative approach to mathematics and science education

    The Tnt1 Retrotransposon Escapes Silencing in Tobacco, Its Natural Host

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    Retrotransposons' high capacity for mutagenesis is a threat that genomes need to control tightly. Transcriptional gene silencing is a general and highly effective control of retrotransposon expression. Yet, some retrotransposons manage to transpose and proliferate in plant genomes, suggesting that, as shown for plant viruses, retrotransposons can escape silencing. However no evidence of retrotransposon silencing escape has been reported. Here we analyze the silencing control of the tobacco Tnt1 retrotransposon and report that even though constructs driven by the Tnt1 promoter become silenced when stably integrated in tobacco, the endogenous Tnt1 elements remain active. Silencing of Tnt1-containing transgenes correlates with high DNA methylation and the inability to incorporate H2A.Z into their promoters, whereas the endogenous Tnt1 elements remain partially methylated at asymmetrical positions and incorporate H2A.Z upon induction. Our results show that the promoter of Tnt1 is a target of silencing in tobacco, but also that endogenous Tnt1 elements can escape this control and be expressed in their natural host

    Arabidopsis HDA6 Regulates Locus-Directed Heterochromatin Silencing in Cooperation with MET1

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    Heterochromatin silencing is pivotal for genome stability in eukaryotes. In Arabidopsis, a plant-specific mechanism called RNA–directed DNA methylation (RdDM) is involved in heterochromatin silencing. Histone deacetylase HDA6 has been identified as a component of such machineries; however, its endogenous targets and the silencing mechanisms have not been analyzed globally. In this study, we investigated the silencing mechanism mediated by HDA6. Genome-wide transcript profiling revealed that the loci silenced by HDA6 carried sequences corresponding to the RDR2-dependent 24-nt siRNAs, however their transcript levels were mostly unaffected in the rdr2 mutant. Strikingly, we observed significant overlap of genes silenced by HDA6 to those by the CG DNA methyltransferase MET1. Furthermore, regardless of dependence on RdDM pathway, HDA6 deficiency resulted in loss of heterochromatic epigenetic marks and aberrant enrichment for euchromatic marks at HDA6 direct targets, along with ectopic expression of these loci. Acetylation levels increased significantly in the hda6 mutant at all of the lysine residues in the H3 and H4 N-tails, except H4K16. Interestingly, we observed two different CG methylation statuses in the hda6 mutant. CG methylation was sustained in the hda6 mutant at some HDA6 target loci that were surrounded by flanking DNA–methylated regions. In contrast, complete loss of CG methylation occurred in the hda6 mutant at the HDA6 target loci that were isolated from flanking DNA methylation. Regardless of CG methylation status, CHG and CHH methylation were lost and transcriptional derepression occurred in the hda6 mutant. Furthermore, we show that HDA6 binds only to its target loci, not the flanking methylated DNA, indicating the profound target specificity of HDA6. We propose that HDA6 regulates locus-directed heterochromatin silencing in cooperation with MET1, possibly recruiting MET1 to specific loci, thus forming the foundation of silent chromatin structure for subsequent non-CG methylation

    Mind the Gap: Transitions Between Concepts of Information in Varied Domains

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    The concept of 'information' in five different realms – technological, physical, biological, social and philosophical – is briefly examined. The 'gaps' between these conceptions are dis‐ cussed, and unifying frameworks of diverse nature, including those of Shannon/Wiener, Landauer, Stonier, Bates and Floridi, are examined. The value of attempting to bridge the gaps, while avoiding shallow analogies, is explained. With information physics gaining general acceptance, and biology gaining the status of an information science, it seems rational to look for links, relationships, analogies and even helpful metaphors between them and the library/information sciences. Prospects for doing so, involving concepts of complexity and emergence, are suggested

    Between Convergence and Exceptionalism: Americans and the British Model of Labor Relations, c. 1867–1920

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    Psychology and legal change: On the limits of a factual jurisprudence.

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