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Strategic Searching and Source Evaluation: Active Learning Teaching Materials
Get PDFDuring the Librarians Active Learning Institute (LALI) 2024, Alexis Gomez, Tricia Martone, and Abigail Murdy developed a 50-minute active learning session for a fictional environmental studies class needing to write a research paper on a topic of their choice using peer reviewed articles. The bulk of the active learning session was encompassed in the two handouts, which are a jigsaw for Web of Science (20 minutes) and a modified Send-A-Problem (Send Along) activity (20 minutes). The lesson was designed for 6 students, though it can be scaled. In the practicum, the Web of Science jigsaw had 3 groups of 2 each teaching themselves in their pairs the contents of one of the handouts. Students were then shuffled so that each student in each of the 2 new groups of 3 had worked on a separate handout. The students then taught each other what they learned, combining the knowledge of the three handouts. Students were put in pairs for the Send Along activity. All groups completed #1, then passed their paper to the left, and this was repeated for #2 and #3. Papers were passed once more after #3 was complete so that groups ended up with their original paper. Reflection on the activity included discussion around what makes a right-sized research question, how useful some Web of Science features were for their searches, how keywords impacted their searches, and what they might do differently in future
The Accurate Conversion of Biological Experiments from Cesium Irradiation to X-ray Irradiation: The Significance, Problems, and the Future of Experimental Radiation Research
Get PDFPreclinical small animal irradiation studies, once conducted on Cesium irradiators, are increasingly being performed with X-ray-based irradiators. The transition stems from concerns regarding national security risks, making X-ray irradiators which are compact and easy to operate an enticing alternative. However, questions regarding the relative biological effectiveness between the two sources have revealed a lack of adequate dosimetric characterization of X-ray beams, standardized protocol for dose calibration, and thorough understanding of experimental biological parameters. A literature review conducted on orthovoltage irradiators has revealed that there are over 54 different types of beam structures used, a dramatic departure from the one uniform beam structure with cesium sources. The lack of consistency and precise dosimetry has resulted in inaccuracies in dose delivery that reach up to 42% across institutions (Pedersen et al. 2016). The complicated physics associated with calibrating orthovoltage irradiators has been thoroughly investigated and reported in literature through measurements and Monte Carlo simulations. However, these results have not yet been translated into practice, and thus many institutions still rely on antiquated calibration procedures. This thesis aims to address the communication between experimental radiation researchers and physicists who could calibrate the irradiators. To do so, a thorough literature review of orthovoltage radiation physics and a complete characterization of the orthovoltage irradiator at Dartmouth College were first conducted. Then, anthropomorphic mouse phantoms were developed from µCT scans of mice and were used with radiochromic film to assess the agreement of dose delivered in a mouse with that predicted by standard AAPM Task Group 61 calibrations in large water equivalent phantoms. Ultimately, findings were incorporated into an app that allows researchers to accurately deliver dose. Following dosimetry calibration, 70 female mice were irradiated with 137Cs gamma rays or equivalent doses of cabinet-based orthovoltage X-rays. The relative biological effectiveness of orthovoltage X-rays was assessed through a variety of biological markers including a CBC, serum chemistry panels, daily mouse activity levels, weight loss, and histopathologic quantification of bone marrow, spleen, liver, and small intestine. We have determined that collaborations between physicists and experimental radiation researchers are essential for facilitating accurate dosimetry and biological assays
Learning to See on the Screen: Exploring Female Performance in Early Film through the Media Ecology Project
Get PDFThis article argues that the development of digital research and teaching platforms are changing the ways we understand and approach audiovisual archives today. Focusing on the Media Ecology’s Semantic Annotation Tool (SAT) and its application to early film, it proposes that this new digital humanities resource profoundly impacts our understanding of female achievement in the development of the nascent cinema. Making reiterative viewing of a single shot or sequence of shots possible, the SAT evidences the importance of access to screen content in archives, the significance of reviewing physical agency on film in conjunction with technical and other developments, and the ongoing, critical need to develop a language capable of describing gestures and physical expression on screen. The article concludes with a reflection on our contemporary access to large collections of digital data and metadata. Microhistory, it is explained, is the methodological tool that allows us to reiteratively view materials while speculating about historical process and change. The development of research/pedagogic digital tools consequently broadens and focuses academic and cultural developments across the digital humanities today
Bulk RNA sequencing analysis of gene expression in staged mouse ovarian follicles
No full textThis project aimed to employ bulk RNA sequencing analysis to quantify the differences in gene expression between staged follicles in ovarian mouse models. The follicles of interest—cortical and medullary—differ by location, activation time, and impact on fertility, indicating potential differences in expression. A dataset of 97 primordial ovarian follicles was curated and sequenced to obtain gene expression readouts. Of these, 82 contained unambiguous metadata; subsequent filtering yielded 44 analyzable follicles. Principal component analysis (PCA) was conducted on the filtered data, revealing a heavy batch effect. Two avenues were explored to rectify this—batch correction using the ComBat-seq method and isolation of a single batch, Batch 5. Batch correction proved largely ineffective, as a batch effect was still observed within corrected data; isolation of a single batch was effective. The PCA of Batch 5 did not reveal a clear impact on gene expression by follicle location within the first two Principal Components. This was corroborated by a Pearson Correlation Plot. Future work focuses on improving batch correction methods, analyzing other Principal Components within Batch 5, and conducting Differential Expression (DE) analysis on both subsets of data to formally quantify differences in gene expression. This approach will thus create opportunities for more targeted exploration of genes which may impact fertility.https://digitalcommons.dartmouth.edu/wetterhahn_2024/1018/thumbnail.jp
Target Selection and Enhancement During Attentional Tracking
Get PDFAt any waking moment, we are bombarded with more sensory information than we can fully process. Attention is necessary to deal with the dynamic world we live in. One fundamental function of vision and attention is to keep track of moving objects, but what are the targets of attention during tracking?
One of the first theories of attentional tracking predicted that targets would be selected at early processing stages. By employing the double-drift illusion, which dissociates physical and perceived positions of moving objects, we investigated which of these positions is selected for tracking. Contrary to earlier theories and in line with newer findings, targets were selected rather late in visual processing, at least after the construction of illusory percepts, for both covert (Chapter One) and overt tracking (Chapter Two).
Furthermore, capacity and speed limits to attentional tracking are hemifield specific. Brain activity in many areas is known to covary with the number of tracked targets, but it was previously unknown whether this effect would also show hemifield bias. Only targets presented in the contralateral hemifield influenced activity in earlier visual areas, while both contralateral and ipsilateral targets affected activity in parietal and frontal areas associated with attention (Chapter Three). Due to the hemifield specific nature of the capacity limit, we conjecture that it should emerge where load dependent activity is strongly contralateral.
Overall, the studies presented in this dissertation illuminate two different aspects of attentional tracking. While selection happens late in the visual hierarchy, capacity and speed limits appear to emerge early in visual processing
