Perceived Motivational Affordances: Capturing and Measuring Students' Sense-Making Around Visualizations of their Academic Achievement Information.

The efficacy of learning analytics is predicated on the validity of techniques used to uncover patterns about student learning and engagement, and the ways in which these patterns are communicated to various stakeholders. How students understand representations of their learning, and whether or not those representations motivate them in positive ways, is not well understood. This dissertation addresses this gap in the literature through two complementary studies. Study 1 utilizes qualitative interviews (n = 60) to investigate how students at-risk of college failure interpret visual representations of their potential academic achievement. Findings suggest an interplay between the information communicated by visualizations and students’ own inclinations towards the information they wished to see. Visualizations showing only the participants academic information, for example, evoked statements focused on personal growth from students when they interpreted the graphs. Visualizations that cast an individual student’s performance against the class average, however, evoked maladaptive responses. Study 2 designed and validated the Motivated Information-Seeking Questionnaire (MISQ) using a college student sample drawn from across the country (n = 551). The MISQ measures constructs that are parallel to mastery, performance-avoid, and performance approach goal orientations as theorized by Achievement Goal Theory. Confirmatory Factor Analysis (CFA) was used to internally validate the MISQ scales, resulting in validation of the performance-approach information-seeking (PAIS) and performance-avoid information-seeking (PVIS) dimensions. Results of external validation indicated that PVIS and PAIS were empirically distinguishable from performance-approach and performance-avoid achievement goal orientations. Multiple regression analysis supported the predictive power of PVIS and PAIS with regard to students’ emotional responses to certain types of visualizations and to what they attributed their success and/or failure, after controlling for relevant demographic characteristics. Taken together, these studies increase our knowledge of the various dimensions students use while interpreting visualizations, and uncovered tensions between what students want to see, versus what it might be more motivationally appropriate for them to see. Both studies suggest three maxims for the design and use of visualizations: 1) Never assume that more information is better; 2) Anticipate and mitigate against potential harm; and 3) Always suggest a way for students to grow.PhDEducation and PsychologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/133441/1/aguilars_1.pd

Customized biomaterials to augment chondrocyte gene therapy

A persistent challenge in enhancing gene therapy is the transient availability of the target gene product. This is particularly true in tissue engineering applications. The transient exposure of cells to the product could be insufficient to promote tissue regeneration. Here we report the development of a new material engineered to have a high affinity for a therapeutic gene product. We focus on insulin-like growth factor-I (IGF-I) for its highly anabolic effects on many tissues such as spinal cord, heart, brain and cartilage. One of the ways that tissues store IGF-I is through a group of insulin like growth factor binding proteins (IGFBPs), such as IGFBP-5. We grafted the IGF-I binding peptide sequence from IGFBP-5 onto alginate in order to retain the endogenous IGF-I produced by transfected chondrocytes. This novel material bound IGF-I and released the growth factor for at least 30 days in culture. We found that this binding enhanced the biosynthesis of transfected cells up to 19-fold. These data demonstrate the coordinated engineering of cell behavior and material chemistry to greatly enhance extracellular matrix synthesis and tissue assembly, and can serve as a template for the enhanced performance of other therapeutic proteins

The overlooked carbon loss due to decayed wood in urban trees

Decayed wood is a common issue in urban trees that deteriorates tree vitality over time, yet its effect on biomass yield therefore stored carbon has been overlooked. We mapped the occurrence and calculated the extent of decayed wood in standing Ulmus procera, Platanus × acerifolia and Corymbia maculata trees. The main stem of 43 trees was measured every metre from the ground to the top by two skilled arborists. All trees were micro-drilled in two to four axes at three points along the stem (0.3 m, 1.3 m, 2.3 m), and at the tree’s live crown. A total of 300 drilling profiles were assessed for decay. Simple linear regression analysis tested the correlation of decayed wood (cm²) against a vitality index and stem DBH. Decay was more frequent and extensive in U. procera, than P. acerifolia and least in C. maculata. Decay was found to be distributed in three different ways in the three different genera. For U. procera, decay did appear to be distributed as a column from the base to the live crown; whereas, decay was distributed as a cone-shape in P. acerifolia and was less likely to be located beyond 2.3 m. In C. maculata decay was distributed as pockets of variable shape and size. The vitality index showed a weak but not significant correlation with the proportion of decayed wood for P. acerifolia and C. maculata but not for U. procera. However, in U. procera, a strong and significant relationship was found between DBH and stem volume loss (R² = 0.8006, P = 0.0046, n = 15). The actual volume loss ranged from 0.17 to 0.75 m³, equivalent to 5%–25% of the stem volume. The carbon loss due to decayed wood for all species ranged between 69–110 kg per tree. Based on model’s calculation, the stem volume of U. procera trees with DBH ≥ 40 cm needs to be discounted by a factor of 13% due to decayed wood regardless of the vitality index. Decayed wood reduces significantly the tree’s standing volume and needs to be considered to better assess the carbon storage potential of urban forests

Mapeo narrativo

In the present article, Stephen Mamber presents purposes, types and examples of narrative mapping, a tool that helps to understand complex narratives in space and time, either films, news, novels or schedules in a train station. Narrative mappings can be as complex and theme-centered, like a territorial map, so they become the true interface to access the text. Since narrative is everywhere, Mamber asks if there is a limit to the possibilities of mapping our surroundings.En el presente artículo, Stephen Mamber expone propósitos, categorías y ejemplos del mapeo narrativo, herramienta que ayuda a comprender narrativas complejas en tiempo y espacio, sean películas, hechos periodísticos, novelas u horarios de una estación de trenes. Los mapas narrativos pueden ser tan complejos y centrados en un tema, como un mapa territorial, que se convierten en la interfaz con la que uno realmente accede al texto. Ya que la narrativa se encuentra en todos lados, Mamber se pregunta si habrá realmente un límite a las posibilidades de mapear nuestro entorno

Anti-Hyperon Enhancement through Baryon Junction Loops

The baryon junction exchange mechanism recently proposed to explain valence baryon number transport in nuclear collisions is extended to study midrapidity anti-hyperon production. Baryon junction-anti-junction (J anti-J) loops are shown to enhance anti-Lambda, anti-Xi, anti-Omega yields as well as lead to long range rapidity correlations. Results are compared to recent WA97 Pb + Pb -> Y + anti-Y + X data.Comment: 10 pages, 4 figure

GPI spectra of HR 8799 c, d, and e from 1.5 to 2.4μ\mum with KLIP Forward Modeling

We explore KLIP forward modeling spectral extraction on Gemini Planet Imager coronagraphic data of HR 8799, using PyKLIP and show algorithm stability with varying KLIP parameters. We report new and re-reduced spectrophotometry of HR 8799 c, d, and e in H & K bands. We discuss a strategy for choosing optimal KLIP PSF subtraction parameters by injecting simulated sources and recovering them over a range of parameters. The K1/K2 spectra for HR 8799 c and d are similar to previously published results from the same dataset. We also present a K band spectrum of HR 8799 e for the first time and show that our H-band spectra agree well with previously published spectra from the VLT/SPHERE instrument. We show that HR 8799 c and d show significant differences in their H & K spectra, but do not find any conclusive differences between d and e or c and e, likely due to large error bars in the recovered spectrum of e. Compared to M, L, and T-type field brown dwarfs, all three planets are most consistent with mid and late L spectral types. All objects are consistent with low gravity but a lack of standard spectra for low gravity limit the ability to fit the best spectral type. We discuss how dedicated modeling efforts can better fit HR 8799 planets' near-IR flux and discuss how differences between the properties of these planets can be further explored.Comment: Accepted to AJ, 25 pages, 16 Figure

Five anthropogenic factors that will radically alter forest conditions and management needs in the Northern United States

The Northern United States includes the 20 states bounded by Maine, Maryland, Missouri, and Minnesota. With 70 million ha of forestland and 124 million people, it is the most densely forested (42% of land area) and most densely populated (74 people/km2) quadrant of the United States. Three recent, large-scale, multiresource assessments of forest conditions provide insight about trends and issues in the North, and collectively these and other supporting documents highlight factors that will be extraordinarily influential in large-scale northern forest management needs over the next 50 years. This review article discusses five of those factors: (1) northern forests lack age-class diversity and will uniformly grow old without management interventions or natural disturbances, (2) the area of forestland in the North will decrease as a consequence of expanding urban areas, (3) invasive species will alter forest density, diversity, and function, (4) management intensity for timber is low in northern forests and likely to remain so, and (5) management for nontimber objectives will gain relevance but will be challenging to implement. Suggested actions to address these factors include the following: develop quantifiable state and regional goals for forest diversity, understand the spatial and structural impacts of urban expansion on forests, develop symbiotic relationships among forest owners, forest managers, forest industry and the other stakeholders to support contemporary conservation goals, and work to understand the many dimensions of forest change. In the next several decades, climate change seems unlikely to overwhelm or negate any of the five factors discussed in this article; rather it will add another complicating dimension.Natural Resource Ecology and Managemen

Ultrahigh Energy Cosmic Rays: The state of the art before the Auger Observatory

In this review we discuss the important progress made in recent years towards understanding the experimental data on cosmic rays with energies \agt 10^{19} eV. We begin with a brief survey of the available data, including a description of the energy spectrum, mass composition, and arrival directions. At this point we also give a short overview of experimental techniques. After that, we introduce the fundamentals of acceleration and propagation in order to discuss the conjectured nearby cosmic ray sources. We then turn to theoretical notions of physics beyond the Standard Model where we consider both exotic primaries and exotic physical laws. Particular attention is given to the role that TeV-scale gravity could play in addressing the origin of the highest energy cosmic rays. In the final part of the review we discuss the potential of future cosmic ray experiments for the discovery of tiny black holes that should be produced in the Earth's atmosphere if TeV-scale gravity is realized in Nature.Comment: Final version. To be published in Int. J. Mod. Phys.