39 research outputs found
The Impact of Learning Assistants on Inequities in Physics Student Outcomes
This study investigates how Learning Assistants (LAs) and related course
features are associated with inequities in student learning in introductory
university physics courses. 2,868 physics students' paired pre- and post-test
scores on concept inventories from 67 classes in 16 LA Alliance member
institutions are examined in this investigation. The concept inventories
included the Force Concept Inventory, Force and Motion Conceptual Evaluation,
and the Conceptual Survey of Electricity and Magnetism. Our analyses include a
multiple linear regression model that examines the impact of student (e.g.
gender and race) and course level variables (e.g. presence of LAs and Concept
Inventory used) on student learning outcomes (Cohen's d effect size) across
classroom contexts. The presence of LAs was found to either remove or invert
the traditional learning gaps between students from dominant and non-dominant
populations. Significant differences in student performance were also found
across the concept inventories.Comment: 4 pages, 2 figures, 3 tables, 2016 Physics Education Research
Conference Proceeding
Scaling of maneuvering performance in baleen whales: larger whales outperform expectations
Despite their enormous size, whales make their living as voracious predators. To catch their much smaller, more maneuverable prey, they have developed several unique locomotor strategies that require high energetic input, high mechanical power output and a surprising degree of agility. To better understand how body size affects maneuverability at the largest scale, we used bio-logging data, aerial photogrammetry and a high-throughput approach to quantify the maneuvering performance of seven species of free-swimming baleen whale. We found that as body size increases, absolute maneuvering performance decreases: larger whales use lower accelerations and perform slower pitch-changes, rolls and turns than smaller species. We also found that baleen whales exhibit positive allometry of maneuvering performance: relative to their body size, larger whales use higher accelerations, and perform faster pitch-changes, rolls and certain types of turns than smaller species. However, not all maneuvers were impacted by body size in the same way, and we found that larger whales behaviorally adjust for their decreased agility by using turns that they can perform more effectively. The positive allometry of maneuvering performance suggests that large whales have compensated for their increased body size by evolving more effective control surfaces and by preferentially selecting maneuvers that play to their strengths.We thank the crews of many research vessels including the R/V John Martin, R/V Fluke, ARSV Laurence M. Gould, R/V Sanna, M/V Antonie, M/V Northern Song, the Cascadia Research Collective and the Shallow Marine Surveys Group; in particular, we thank John Douglas, Andrew Bell, Shaun Tomlinson, Steve Cartwright, Tony D'Aoust, Dennis Rogers, Kelly Newton, Heather Riley, Gina Rousa and Mark Rousa. We also thank Brandon L. Southall, Alison K. Stimpert and Stacy L. DeRuiter for their role in collecting data as part of the SOCAL-BRS project. We thank Matt S. Savoca, Julian Dale and Danuta M. Wisniewska for assistance with data collection. Finally, we thank John H. Kennedy, Michael A. Thompson and the NSF Office of Polar Programs.Ye
Socializing One Health: an innovative strategy to investigate social and behavioral risks of emerging viral threats
In an effort to strengthen global capacity to prevent, detect, and control infectious diseases in animals and people, the United States Agency for International Development’s (USAID) Emerging Pandemic Threats (EPT) PREDICT project funded development of regional, national, and local One Health capacities for early disease detection, rapid response, disease control, and risk reduction. From the outset, the EPT approach was inclusive of social science research methods designed to understand the contexts and behaviors of communities living and working at human-animal-environment interfaces considered high-risk for virus emergence. Using qualitative and quantitative approaches, PREDICT behavioral research aimed to identify and assess a range of socio-cultural behaviors that could be influential in zoonotic disease emergence, amplification, and transmission. This broad approach to behavioral risk characterization enabled us to identify and characterize human activities that could be linked to the transmission dynamics of new and emerging viruses. This paper provides a discussion of implementation of a social science approach within a zoonotic surveillance framework. We conducted in-depth ethnographic interviews and focus groups to better understand the individual- and community-level knowledge, attitudes, and practices that potentially put participants at risk for zoonotic disease transmission from the animals they live and work with, across 6 interface domains. When we asked highly-exposed individuals (ie. bushmeat hunters, wildlife or guano farmers) about the risk they perceived in their occupational activities, most did not perceive it to be risky, whether because it was normalized by years (or generations) of doing such an activity, or due to lack of information about potential risks. Integrating the social sciences allows investigations of the specific human activities that are hypothesized to drive disease emergence, amplification, and transmission, in order to better substantiate behavioral disease drivers, along with the social dimensions of infection and transmission dynamics. Understanding these dynamics is critical to achieving health security--the protection from threats to health-- which requires investments in both collective and individual health security. Involving behavioral sciences into zoonotic disease surveillance allowed us to push toward fuller community integration and engagement and toward dialogue and implementation of recommendations for disease prevention and improved health security
Comparative performance of various plasma polysiloxane films for the pervaporative recovery of organics from aqueous streams
PECVD process for the preparation of proton conducting membranes for micro fuel cells. Impedance probe measurements and material characterizations
A complete PECVD process for the plasma polymerization of miniature proton
exchange membranes (PEM) is presented. Styrene and trifluoromethane sulfonic
acid are used as plasmagen precursors in a capacitive coupled low pressure
discharge. The process is monitored by impedance probe measurements to
ensure stability and reproducibility. FTIR analyses show that such membranes
are mainly made up of a polystyrene-like matrix with grafted sulfonic acid
groups, which proportion is tuneable as a function of the plasma parameters.
The best results in term of deposition rate, monomer structure retention and
PEM performances are obtained under pulsed plasma conditions, enhancing
radical processes compared to continuous plasma. Because of their thinness
and cross-linked structure, such membranes exhibit a similar proton
conduction ability and a methanol permeability reduced by a factor 150
compared to Nafion. SEM observations show a good
compatibility of plasma polymerized membranes whatever the substrate is.
Consequently, PECVD process enables their better integration in micro fuel
cells compared to conventional spin coating method
Highly selective Reverse Osmosis membranes incorporating biomimetic Artificial Water Channels
International audienc
Development of Reverse Osmosis membranes incorporating Artificial Water Channel (AWC) Systems
International audienc
Développement par procédés plasma d’assemblages membrane-électrodes pour la production/séparation d’hydrogène par photoélectrolyse de l’eau
National audienc