Search

The research presented in chapters 2, 3, and 4 in this dissertation uses a sociocultural and sociohistorical lens, particularly around power, authority of knowledge and identity formation, to investigate the complexity of engaging in, supporting, and evaluating high-quality argumentation within a college biochemistry inquiry-oriented classroom. Argumentation skills are essential to college and career (National Research Council, 2010) and for a democratic citizenry. It is central to science teaching and learning (Osborne et al., 2004a) and can deepen content knowledge (Jimenez-Aleixandre et al., 2000; Jimenez-Aleixandre & Pereiro-Munhoz, 2002). When students have opportunities to make claims and support it with evidence and reasoning they may also increase their problem-solving and critical thinking capacity (Case, 2005; Willingham, 2007). Overall, this has implications in supporting students to become increasingly literate in scientific ideas, language, and practices. However, supporting argumentation can be challenging for instructors, particularly in designing learning environments that facilitate and evaluate both the process and the product during student discussions (Duschl & Osborne, 2002). Fostering argumentation is complex and requires explicit modeling and multiple opportunities for dialogic interactions. This dissertation will examine how several facets influence argumentation in order to support instructors in implementing and improving argumentation in their inquiry-oriented classrooms. These facets include access to language and use of discursive moves, classroom design, curriculum and instructional activities, and interactional dynamics and power negotiation. The data set for this dissertation is a transcript generated from the audio- and video capture of a 7-minute student discussion around a mechanism in the TCA (TriCarboxylic Acid) cycle, as well as student writing, and course documents from student portfolios. This dissertation, organized using the manuscript style structure, will present three standalone chapters, each with a specific focus related to the central theme of supporting argumentation, which is the connecting thread. Chapter 2 will discuss how power is negotiated during the argumentation process and how interaction dynamics can support or inhibit the quality of argumentation. Chapter 3 will provide assessment and evaluation support to instructors who want to guide their students in meeting high quality levels in both the process and product of argumentation. Finally, chapter 4 will explore the influence of pedagogical, and instructional resources and tools on the quality of argumentation. This includes a discussion of the influence of classroom talk, particularly discursive moves and interactional dynamics, as well the curriculum and instructional activities, and the design features of the learning environment. Each chapter will conclude with instructional implications that provide practical guidance in the form of pedagogical activities to instructors. Partial funding for this dissertation was received from a PSC-CUNY Cycle 44 Research Award (66799-00 44). Findings suggest that the classroom design can support collaboration and the dialogic nature of argumentation, and the curriculum and activities can act as resources for students to share and negotiate multiple perspectives, but that instructors can also influence the process of argumentation by utilizing specific discursive moves, such as telling and revoicing, to promote or inhibit argumentation. The results, specifically from chapter 4, also propose that instructors model and share the expected criteria for high quality components of argumentation. The need for instructors to be aware of the criteria for high levels of quality for each of the argumentation components is a critical implication of this research. The criterion is presented in this dissertation and is derived from a review of multiple findings by researchers of argumentation, as well the scientific community at large. Creating structures and implementing targeted pedagogical strategies that support argumentation can lead students to use the process of argumentation as an empowerment tool to enact agency and negotiate power. This has the potential to sustain the success of science students, create a community of practice, and increase equity and access for all. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

This qualitative study critically examines the exclusion and inclusion of children with special educational needs and/or disabilities in Chinese primary schools. The settings are four mainstream schools and two special schools in one large city in East Coast China. The research investigates how 37 mainstream school teachers view and practise exclusion and/or inclusion. Underlying influences are examined, taking into account the contexts of the local schools, the education systems, and broader Chinese society. The study aims to offer a deeply contextualised understanding of inclusive education in China, beyond its current practice and national policy of 'Learning in Regular Classrooms'. Informed by critical realism, the thesis analyses inclusion on the four planes of social being: bodies in material relations with nature, interpersonal relations, social structures and inner being. The thesis illustrates the importance of analysing inclusive education critically, holistically, and coherently at all four planes of social being. Disability and inclusion are understood through the critical realist concept of stratified ontology: the Empirical, the Actual and the Real. The intention is to reconcile conflicts between the medical and the social models of disability and to move the inclusion debates forward, in China and elsewhere. The analysis aims to uncover the real forces behind educational inclusion and exclusion in Chinese schools. Confucianism is not often associated with inclusion, but the possibility of Confucianism, rather than human rights, offering practical advocacy for inclusion is explored. Also highlighted is the crucial need for teachers to believe in inclusion and see it as benefiting all children. The internalised values and motives can be powerful drives for inclusion despite structural barriers and practical difficulties. The thesis explores the restructuring of values, caring for inner wellbeing, and building relationships as approaches to enable real transformation in schools and society towards greater inclusion.

Bacteria are capable of sensing changes in their environment and responding to those changes by altering patterns of gene expression. There are many mechanisms by which bacteria can sense internal and external signals. The most well studied systems for this, two-component systems, are composed of a histidine kinase that can act as a detector and a response regulator that when activated by the histidine kinase can carry out a function. In the case of regulating gene expression, once a signal is detected, the response regulator can directly act as a transcription factor or control the activity of other transcription factors to determine the genes that are transcribed and the genes that are not. Historically, much of gene regulation has been thought to be regulated at the level of transcription. There are, however, several processes that take place after a gene is transcribed that ultimately determine the level of a gene product These include mRNA stability, translation initiation, translation efficiency, and protein degradation, all of which the cell could potentially target to fine-tune protein levels. Many such post-transcriptional mechanisms of regulation have been identified, such as controlled proteolysis and the regulation of translation by riboswitches. Here I report on mechanisms operating at the level of translational efficiency and mRNA stability that control entry into a multicellular state in the bacterium Bacillus subtilis. Like many bacteria, B. subtilis can form architecturally complex communities known as biofilms. Biofilm formation by B. subtilis is largely governed by a dedicated repressor for matrix production, SinR. At the transcriptional level, biofilm formation is regulated by the response regulator Spo0A, which turns on the gene for the anti-repressor SinI. SinI, in turn, binds to and inactivates SinR. The work that I have been a part of and that is presented here has revealed two additional mechanisms in which SinR is regulated post-transcriptionally. The first is a simple mechanism in which B. subtilis can sense changes in nutrient availability without a dedicated protein or RNA. Instead certain synonymous serine codons cause pausing when serine levels are reduced, and enrichment for these codons in sinR decreases its rate of translation under biofilm-inducing conditions, contributing to derepression of matrix genes. The second, which is the main focus of this thesis, acts at the level of the stability of the mRNA for sinR. This mechanism was unexpectedly uncovered while determining the function of three mysterious proteins, YlbF, YmcA, and YaaT, which are required for biofilm formation. I have found that YlbF, YmcA, and YaaT form a three-protein complex that interacts with and is required for the full activity of the ribonuclease RNase Y. This complex is required for biofilm formation because it destabilizes the mRNA for sinR. In addition RNA-sequencing experiments reveal a global role for the complex in RNA turnover. Turnover of many known targets of RNase Y, including mRNA and non-coding RNAs, are dependent on the complex. In light of these findings, the decision to form a multicellular community can be seen as the convergence of three regulatory pathways operating at three different levels of the expression of the gene for the master regulatory protein for biofilm formation SinR., Biology, Molecular and Cellular