Hydrological Response Patterns and Solute Flux in Canadian Shield Basins: Role of Different Physical Features and Antecedent Moisture Conditions

Patterns of stream flow in relatively undisturbed Canadian Shield basins are closely linked to their physical and vegetative characteristics and meteorological conditions. The physical characteristics include topography, soil-till composition, depth and structure, slope morphology and bedrock geology. Hydrological flowpaths through, and in-situ chemical processes in the soil-till matrix are influenced greatly by the composition of these features and by the antecedent hydrological conditions preceding a given storm or snowmelt event. A long term data set, collected by the Dorset Environmental Science Centre, is used to examine eight forested basins within the Muskoka-Haliburton region of south-central Ontario. The basins have a range of physical characteristics representative of this part of the Canadian Shield. Statistical analysis of streamflow from all basins for approximately 20 years indicates that the response of basins with shallow till is significantly more variable than basins with deeper till. For this data set, streamflow patterns were assessed relative to ambient temperature and precipitation meteorological conditions. This analysis quantifies the differences between annual responses in shallow and deeper tilled basins. A new approach is taken to quantify antecedent moisture conditions in the study basins. These antecedent moisture conditions are related to precipitation magnitude and basin runoff coefficients. Regression equations quantify these relationships for the study basins and demonstrate significant differences which are related to the physical characteristics of the basin. A daily time series of antecedent moisture conditions constructed for four study basins for four consecutive years explains runoff coefficient patterns in basins with shallow and deep till. Temporal patterns of dissolved ions, sulphate (SO42-) chloride (Cl-), calcium (Ca2+) and dissolved silica (SiO2) and alkalinity export in surface water were assessed to examine the distribution of these solutes across the range of annual storm events at each site. Storm and spring melt events that are exceeded 20% of the time during the course of a year are responsible for the majority of solute export during a year; however, the relative importance of storm events on solute export differs between deeper and shallow tilled basins and during dry and wet years

Cultivating a Learner’s Stance for Engagement in Teacher-Inquiry: An Aim for Writing Pedagogy Education

This dissertation argues that writing teacher educators (WTEs) can more purposefully advance their commitment to sponsoring inquiry-oriented teacher development by helping pre-service and practicing writing teachers examine how they are developing as inquirers. Building from scholarship in Composition and English Education and the findings from a narrative-based qualitative study that included four secondary and post-secondary teachers of writing, I have named this attention to how teachers learn and grow their inquiry processes a learner’s stance for engagement in teacher-inquiry. This stance is a readiness to see and engage professional work with an eye toward growing one’s ability to engage in teacher-inquiry. Drawing from Jean Lave and Etienne Wenger’s theory of learning, legitimate peripheral participation, I present three kinds of learning activities that WTEs can foreground in teacher education contexts to cultivate a learner’s stance. These activities include: developing goals for teacher development, exploring tensions involved in the interpretation of teaching moments, and negotiating stakeholder positions. Using findings from the qualitative study, the dissertation chapters demonstrate how these learning activities enable teachers to examine and develop the frameworks supporting their inquiry practices. Additionally, the conclusion offers concrete ways that WTEs can implement these activities in teacher education courses. Advisor: Shari J. Stenber

Asking and Understanding Questions: An Inquiry-Based Framework for Writing Teacher Development

Teachers develop when they critically examine the questions they ask about their work because questions make pedagogical beliefs visible and available for critical reflection and revision. In a standards-based educational climate—a time when writing becomes a set of measurable skills rather than a complex social practice—teachers may feel that a critical examination of their questions is (at best) a luxury or (at worst) a distraction to work they need to accomplish. Therefore, writing teacher educators may find it increasingly challenging to help teachers engage in reflexive inquiry. This essay describes a Deweyian-informed framework that shows how addressing inquiries and critically examining inquiries are processes that complement one another. Using examples from two contexts commonly implemented to promote teacher development, this essay argues the asking/understanding framework provides useful language for helping WTEs and teachers negotiate varying expectations for pedagogical inquiry and teacher development

Connecting Our Pedagogical Questions and Goals: An Exercise for Writing Teacher Development

In this article, the author argues writing teachers can more fully inquire into their questions about teaching writing by paying closer attention to the ways their goals for teacher development shape their engagement in pedagogical inquiry. To explain these connections and illustrate these possibilities, the author shares findings from a narrative-inquiry study that examined the development of pedagogical inquiry in the lives of four teachers of writing. Using the participating teachers’ shared goals for teacher development, the author demonstrates how writing teachers can reflect upon the development of pedagogical inquiry, stretch themselves to practice other aspects of pedagogical inquiry, and re-see professional development structures. This research extends current scholarship on writing teacher development by deepening the field’s conception of writing teacher development

Enacting Rhetorical Listening: A Process to Support Students’ Engagement with Challenging Course Readings

Many educators assign course readings to purposefully enlarge students’ perspectives. In doing so, though, educators may face a range of behaviors—reluctance, resistance, avoidance, disengagement—from students who feel that such readings negatively press upon their prior knowledge, belief systems, or educational goals. This teaching challenge is often present for social justice educators. However, “rhetorical listening,” a rhetorical theory developed by Ratcliffe (2005), is a pedagogical tool that can help shift students’ understandings of and expectations for the activity of reading, thereby creating a learning environment that supports meaningful engagement with challenging course readings. In this article, the author outlines a process for enacting rhetorical listening and describes the pedagogical outcomes that have been achieved through this process

Cultivating a Learner’s Stance for Engagement in Teacher-Inquiry: An Aim for Writing Pedagogy Education

This dissertation argues that writing teacher educators (WTEs) can more purposefully advance their commitment to sponsoring inquiry-oriented teacher development by helping pre-service and practicing writing teachers examine how they are developing as inquirers. Building from scholarship in Composition and English Education and the findings from a narrative-based qualitative study that included four secondary and post-secondary teachers of writing, I have named this attention to how teachers learn and grow their inquiry processes a learner’s stance for engagement in teacher-inquiry. This stance is a readiness to see and engage professional work with an eye toward growing one’s ability to engage in teacher-inquiry. Drawing from Jean Lave and Etienne Wenger’s theory of learning, legitimate peripheral participation, I present three kinds of learning activities that WTEs can foreground in teacher education contexts to cultivate a learner’s stance. These activities include: developing goals for teacher development, exploring tensions involved in the interpretation of teaching moments, and negotiating stakeholder positions. Using findings from the qualitative study, the dissertation chapters demonstrate how these learning activities enable teachers to examine and develop the frameworks supporting their inquiry practices. Additionally, the conclusion offers concrete ways that WTEs can implement these activities in teacher education courses. Advisor: Shari J. Stenber

Grazing Usage Over Time and Space in the Thunder Basin Ecoregion

National grasslands are public lands that have diverse and critical uses. They serve as wildlife habitat, contain mineral resources, and are used recreationally. The Thunder Basin National Grassland, located in the Powder River Basin of Wyoming, spans more than 500,000 acres and local ranchers rely on that acreage to feed their cattle. Effective management of these grazing lands is challenging because agency managers must balance multiple private and public objectives. Advancing rangeland policy requires an accurate understanding of previous grazing history. Even so, few long-term, quantitative records of grazing intensity on this land exist. To address this gap, we digitized physical records of four decades of grazing usage. We analyzed this data to examine variation in grazing intensity over time and space. We found that there was a steady increase in grazing intensity over time, but it fell dramatically in the early 2000s. This is an important observation that can help government agencies understand how various social and environmental factors impact grazing intensity. Application of this understanding can help create sustainable grassland policies

Dipeptides in cell culture - Tools for performance increase and risk reduction

Supplying mammalian cells with certain amino acids can be challenging. These challenges range from chemically instable components like L-glutamine to barely soluble ones like L-tyrosine. Scientists in the parenteral nutrition space realized early that coupling the troublesome amino acid to another, forming a dipeptide, can be an elegant solution1,2. In the field of cell culture, only glutamine-containing dipeptides have been established. L-alanyl-L-glutamine is the most common peptide, often sold under a variety of trade names, but there are more products with exciting properties that are not commonly used in the field. The study at hand summarizes screenings with two different CHO cell lines that measured the impact of replacing single amino acids with dipeptides. The dipeptides tackle two types of challenges: glutamine stability and solubility enhancement. For the first challenge, alternative glutamine peptides were investigated and compared to the current benchmark. It was found that while all of them offered chemical stability, the impact on cell growth, titer and metabolites were different. This was shown in both batch and fed-batch experiments. For the second challenge, L-tyrosine as well as other critical amino acids were coupled to solubility-increasing amino acids and tested for their capability to replace the free amino acids in a cell culture medium. Especially for a glycyl-L-tyrosine dipeptide, it could be shown that the peptide is utilized by the cells and overcomes the solubility challenge at neutral pH. This is of significant relevance to an industrial cell culture user, as the current solution to formulate a highly concentrated feed containing L-tyrosine is to use a high pH. That introduces a process risk, as a malfunction in process control can lead to a lost batch. Using a L-tyrosine containing dipeptide is shown to be an elegant solution to the challenge. 1 Grimble, GK, Annu. Rev. Nutr. 1994; 14:419-47 2 Fuerst, P, J Nutr. 2001 Sep;131(9 Suppl):2562S-8