1,671 research outputs found
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A story, a story: A children\u27s neighborhood performance project
This project entitled A story, a story: a neighborhood performing arts project, focused on transforming a chosen piece of children\u27s literature into a live performance. It was a process driven project which did not solely focus on the final production. Within this project I decided to use the conceptual framework as a basis for teaching drama and movement instead of the rote method of learning
Effects of a Distributed Computing Architecture on the Emerald Nanosatellite Development Process
Building satellites with greater capabilities on shorter timelines requires changes in development approach. Relative to previous satellite projects in Stanford’s Space Systems Development Laboratory (SSDL), the Emerald Nanosatellite system is highly complex. Its mission requires numerous experiments and relatively sophisticated subsystem capabilities. To develop this system on a short two-year timeline required a new development approach to simplify system integration. As a result, the Emerald development team adopted a modular distributed computing architecture. While this decision imposed many changes on Emerald’s design process, the benefits of the distributed architecture for system integration and testing justified its selection. This approach has already affected the early stages of engineering model integration, and is expected to provide flexibility throughout construction and integration of the flight hardware. In addition the distributed architecture developed for the Emerald project will provide a useful tool for future development efforts in the SSDL and the small satellite development community
The rhenium isotope composition of Atlantic Ocean seawater
The concentrations and isotopic compositions of rhenium are presented from seawater samples obtained from the primary station for the Bermuda Atlantic Time Series Study in the North Atlantic Ocean and from the 40oS UK GEOTRACES expedition in the South Atlantic Ocean. Salinity-normalized Re concentrations in both locations range between ∼6.8–7.7 ppt between 50–5000 m depth, consistent with previously published concentration data from the North Atlantic and North Pacific Oceans. Rhenium isotope values (expressed as δ187/185Re relative to NIST 3143) exhibit minimal variation around an average value of −0.17 ± 0.12‰ (n = 12, 2 S.D.), irrespective of water depth or water mass. These results confirm that the isotopic composition of perrhenate (ReO4−) in seawater is uniform. The new data establish a baseline for evaluating the isotopic mass balance of Re, and for future assessments of whether this global cycle can be disturbed by changes in seafloor redox and/or global weathering rates
Introducing high school biology students to biochemistry with a short, content-oriented module
Many STEM disciplines are underrepresented to High School students. This is problematic as many students\u27 decisions for college are shaped by their experiences and achievements in high school. Short content-oriented modules have been shown to encourage science identity and otherwise benefit the students\u27 learning. Following the ASBMB\u27s outreach protocol, we developed a short content-oriented module aimed at a high school biology classroom. Students interacted with 3D models of DNA and transcription factors while exploring structure–function relationships and introductory biochemistry topics. The high school teacher was impressed with the students\u27 response to the module, specifically the ease with which students learned, their enthusiasm, and their recall of the experience. We provide all materials necessary to use this module, including student worksheet and printable model coordinates. We encourage both high school instructors and professional biochemists to consider similar module using physical models
Characterization of sediment movement in tidal creeks adjacent to the gulf intracoastal waterway at Aransas National Wildlife Refuge, Austwell, TX: study of natural factors and effects of barge-induced drawdown currents
The coastal wetlands at Aransas National Wildlife Refuge near Austwell, Texas,
support the last migrating population of whooping cranes during the winter months
(October through April). With a population currently at 216 individuals, these are the
rarest cranes in the world. The wetlands in which they winter are a part of the San
Antonio Bay system, a bay that receives constant fresh water flow from the Guadalupe
River. Currently there is a plan for using water diverted from the Guadalupe River just
before it enters San Antonio Bay as a water supply for the greater San Antonio
metropolitan area located 200 km to the northwest. The Guadalupe River delivers
nutrients and sediment into the estuary along with fresh water. Because of the
importance of sediment within a tidal wetland ecosystem, it is imperative to understand
the sediment budget and underlying forces that drive it if one is to ultimately grasp how
this ecosystem functions. To document natural and anthropogenic factors exerting
control over sediment movement in this system, three sites on tidal creeks near the
boundary between marsh and bay were chosen. The Gulf Intracoastal Waterwayparallels the marsh edge. Over six, non-consecutive weeks water level and velocity were
automatically monitored in the tidal creeks. Automated water samplers extracted water
samples that were analyzed for suspended sediment. In addition, bedload traps were
deployed in one creek to monitor sediment movement along the channel bottom. Inflow
exceeded outflow during the study. As a result there was a net influx of suspended
sediments into the marsh. Bedload material also moves with current direction, and it
appears to move in response to barge induced outflow currents. Barges passing on the
Gulf Intracoastal Waterway exert influence on water level, flow direction, and velocity
within tidal creeks. Natural factors such as winds, tides, and freshwater input from
upland runoff or river discharge also impact suspended and bedload sediments
Big Data And The Well-Being Nexus: Tracking Google Search Activity By State IQ
In the era of “big data,” internet search activity can provide interesting insight into human behavior. Here we used the Google Correlate algorithm (a database tracking billions of user searches) to identify search terms that co-varied most strongly with U.S. state-level IQ and wellbeing (see Pesta, McDaniel, & Bertsch, 2010). First, we identified the 100 strongest positive (e.g., crock pot applesauce, custom woodworking) and negative (e.g., ASVAB for Dummies, Hello Kitty) search term covariates for state IQ. We then rationally clustered search terms into composites (e.g., “food,” “job seeking activity”) based on similarity of concept. Thereafter, we correlated the composite scores with other well-being variables (e.g., crime, health). Search-term composite scores correlated stronglywith allwell-being variables.We offer post-hoc explanations for the various composite-score correlations, showing how state differences in internet search activity fit within the “well-being nexus” for the U.S.Moreover, we explore how the use of Google Correlate can inform additional research inquires in this domain
Formula electric : powertrain
The Santa Clara Formula Electric team designed, and manufactured a powertrain for an electric racecar according to the rules prescribed by the SAE International Formula Electric competition. The powertrain is divided into subsystems: the battery pack, battery pack cooling system, motor controller, and the motor. The battery pack was constructed, but full electrical connection of all cells were not made. The pack was not integrated with the motor and motor controller. In addition, due to time constraints, extensive testing could not be completed
Controls on the cadmium isotope composition of modern marine sediments
Continental margin sediments have been identified as the dominant sink in the marine budget of cadmium (Cd). The isotopic composition of this important output flux is, however, unknown. Here we present, with measurements on the Argentine continental margin, the first observational constraints on the isotopic composition of Cd in modern marine oxic and sub-oxic sediments. We identify two main removal mechanisms of Cd; in organic material, and by sulfide formation. Surface margin sediments (0–0.5 cm), with dissolved O2 below detection from ∼0.5 cm, are isotopically lighter than overlying oxygenated waters. A mass balance for these surface sediments indicates that Cd is present dominantly as organically-bound particulate Cd. In sub-surface sediments, Cd concentrations increase in the zone of nitrate reduction, and attain similar isotopic compositions as the water that overlies the sediment (i.e. ∼0.35‰ in deep waters). These observations are consistent with a downward diffusive flux of seawater Cd and redox-driven quantitative removal of that Cd during sulfide precipitation. In combination, these two routes of Cd removal lead to burial of isotopically light organic Cd in margin sub-oxic sediments that enables the global isotopic Cd budget to be balanced
Rats that sign-track are resistant to Pavlovian but not instrumental extinction
Individuals vary in the extent to which they attribute incentive salience to a discrete cue (conditioned stimulus; CS) that predicts reward delivery (unconditioned stimulus; US), which results in some individuals approaching and interacting with the CS (sign-trackers; STs) more than others (goal-trackers; GTs). Here we asked how periods of non-reinforcement influence conditioned responding in STs vs. GTs, in both Pavlovian and instrumental tasks. After classifying rats as STs or GTs by pairing a retractable lever (the CS) with the delivery of a food pellet (US), we introduced periods of non-reinforcement, first by simply withholding the US (i.e., extinction training; experiment 1), then by signaling alternating periods of reward (R) and non-reward (NR) within the same session (experiments 2 and 3). We also examined how alternating R and NR periods influenced instrumental responding for food (experiment 4). STs and GTs did not differ in their ability to discriminate between R and NR periods in the instrumental task. However, in Pavlovian settings STs and GTs responded to periods of non-reward very differently. Relative to STs, GTs very rapidly modified their behavior in response to periods of non-reward, showing much faster extinction and better and faster discrimination between R and NR conditions. These results highlight differences between Pavlovian and instrumental extinction learning, and suggest that if a Pavlovian CS is strongly attributed with incentive salience, as in STs, it may continue to bias attention toward it, and to facilitate persistent and relatively inflexible responding, even when it is no longer followed by reward
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