Afternoon concurrent track 1: Sustainability in the K-16 classroom

AFTERNOON CONCURRENT TRACK 1: SUSTAINABILITY IN THE K-16 CLASSROOM Moderator Gale Sinatra Student Union Room 207 Ellen Ebert – Using the STS/EEE Model in 6-12 Curriculum to Understand the Sustainability Issues Related to the Colorado River System Abstract: Beginning in 1982, the National Science Teachers Association called for curriculum designers to develop materials that demonstrate the interconnectedness among science, technology and societal issues while presenting both positive and negative influences. This session will focus on using the STS/EEE learning model to design curriculum for secondary science that emphasizes sustainability issues focused on the Colorado River system. The presentation will outline the essential features of the STS/EEE model, then engage participants in applying the model in a novel situation. Rebecca Reichenbach – CCSD Action Research: Understanding the Urban Heat Island Effect Abstract: Due to the unique placement of Western High School within a concrete and asphalt island and a result construction project to rebuild it, a group of science teachers from Western High became interested in how the new construction would affect the urban heat island footprint of their school. A student project was developed to track and document the construction process over a two-year timeframe. The participating teachers used action research to study the impact of the project on their teaching practice and student learning. Three inquiry-style laboratory activities were created to teach students about heat concepts and the effect of heat islands. A misconceptions survey, along with student journaling, were used as data sources for determining changes in student understanding. Results show significant conceptual change in the grade 9 students, with less significant change for the older student population. This presentation will describe the research context, process, and its impact on participating students and teachers. Nick Pretasky – Energy…Catch the Buzz!, Abstract Are you looking to get your students up and moving, discovering energy, and developing critical thinking skills to make decisions about their personal energy use? The topic of energy is a growing concern in our society. It is imperative that students are provided with opportunities to discover the role we play in how our energy is created and consumed. This session is designed for formal and non-formal educators with tools and activities to help students in grades PreK-8 learn about their relationship with energy and investigate the environmental issues related to energy’s role in society. Dale Walsh – Sustaining Indoor Environmental Quality in the Classroom to Improve Learning Abstract: This presentation will include the basics of establishing and maintaining good indoor environmental quality in a school environment. Designing and maintaining adequate amounts of clean outdoor air to dilute pollutants generated from both the environment and the occupants is important in reducing transmission of diseases between students and in reducing exposure to building related contaminants and other potentially harmful particulates. To illustrate the value and problems that can arise from poor indoor environmental quality, a case study of an Arizona school with high profile indoor air quality problems will be addressed. In addition, studies regarding improved learning attributed to building schools under Green Building systems will be presented

Morning concurrent track 1: What does it mean for K-12 students to think about sustainability in the Western U.S.?

MORNING CONCURRENT TRACK 1: WHAT DOES IT MEAN FOR K-12 STUDENTS TO THINK ABOUT SUSTAINABILITY IN THE WESTERN U.S.? Moderator Kent Crippen Student Union Room 207 Ellen Ebert - Using the STS/EEE Model in 6-12 Curriculum to Understand the Sustainability Issues Related to the Colorado River System (repeats Afternoon Concurrent Session #1) Abstract: Beginning in 1982, the National Science Teachers Association called for curriculum designers to develop materials that demonstrate the interconnectedness among science, technology and societal issues while presenting both positive and negative influences. This session will focus on using the STS/EEE learning model to design curriculum for secondary science that emphasizes sustainability issues focused on the Colorado River system. The presentation will outline the essential features of the STS/EEE model, then engage participants in applying the model in a novel situation. Rebecca Reichenbach – CCSD Action Research: Understanding the Urban Heat Island Effect (repeats Afternoon Concurrent Session #1) Abstract: Due to the unique placement of Western High School within a concrete and asphalt island and a result construction project to rebuild it, a group of science teachers from Western High became interested in how the new construction would affect the urban heat island footprint of their school. A student project was developed to track and document the construction process over a two-year timeframe. The participating teachers used action research to study the impact of the project on their teaching practice and student learning. Three inquiry-style laboratory activities were created to teach students about heat concepts and the effect of heat islands. A misconceptions survey, along with student journaling, were used as data sources for determining changes in student understanding. Results show significant conceptual change in the grade 9 students, with less significant change for the older student population. This presentation will describe the research context, process, and its impact on participating students and teachers. Allison Brody, Amy Page – Environmental Literacy as an Indicator for Urban Sustainability Abstract: For sustainability initiatives to be successful, citizens must have the knowledge, action skills, and motivation to support and participate in these initiatives. In other words, Urban Sustainability will not be successful unless our citizens are environmentally literate. The responsibility for creating this “environmentally literate” citizenry should fall in large part to educators, both in the formal and non-formal sectors. Therefore, these educators need a clear understanding of the specific knowledge and action skills that our citizens need. In this session, we will explore the competencies that citizens need to engage in sustainability practices in Nevada, and how educators can incorporate these competencies into their curricula and programs. Marcel Parent, Signa Gundlach – Sustainability Education at the Springs Preserve: Broad Strokes and Targeting Standards Abstract: Sustainability is a rather unwieldy and challenging area in education. From the broad but vague concepts defining it, to the innumerable sectors of human activities in which it applies, learning about sustainability is at the same time wonderfully simple and terrible complex. This presentation will introduce the participants to some of the approaches taken at the Springs Preserve to make learning about sustainability an engaging experience that will impact future behavior

Surfing the Semester: A Study of the Flow of Active Learning Implementation

Instructional reforms have been called for on a national level. Little data exists as to how changes take place. This study explored the implementation of active learning practices by non-tenure and tenure track faculty over the course of a semester. Faculty were introduced to evidence based pedagogy through workshops and faculty learning communities. Their instructional practices within a semester were tracked through observations conducted using the Classroom Observation Protocol for Undergraduate STEM (COPUS). Interviews were conducted to gain insight into reasons for instructional trends. A general trend downward was observed through the semester but was not found to be statistically significant at different time-points. A possible Simpson’s paradox was detected in the collapsed COPUS categories of Instructor Guiding (G) and Students Working (SW) that may also be interfering with broad interpretation. Recommendations are made for further data collection to increase power and to use care before interpreting collapsed COPUS categories.NSF DUE 152505

Static length changes of cochlear outer hair cells can tune low-frequency hearing

The cochlea not only transduces sound-induced vibration into neural spikes, it also amplifies weak sound to boost its detection. Actuators of this active process are sensory outer hair cells in the organ of Corti, whereas the inner hair cells transduce the resulting motion into electric signals that propagate via the auditory nerve to the brain. However, how the outer hair cells modulate the stimulus to the inner hair cells remains unclear. Here, we combine theoretical modeling and experimental measurements near the cochlear apex to study the way in which length changes of the outer hair cells deform the organ of Corti. We develop a geometry-based kinematic model of the apical organ of Corti that reproduces salient, yet counter-intuitive features of the organs motion. Our analysis further uncovers a mechanism by which a static length change of the outer hair cells can sensitively tune the signal transmitted to the sensory inner hair cells. When the outer hair cells are in an elongated state, stimulation of inner hair cells is largely inhibited, whereas outer hair cell contraction leads to a substantial enhancement of sound-evoked motion near the hair bundles. This novel mechanism for regulating the sensitivity of the hearing organ applies to the low frequencies that are most important for the perception of speech and music. We suggest that the proposed mechanism might underlie frequency discrimination at low auditory frequencies, as well as our ability to selectively attend auditory signals in noisy surroundings.Funding Agencies|National Science Foundation [NSF PHY11-25915]</p

TIN2-Tethered TPP1 Recruits Human Telomerase to Telomeres In Vivo▿

Recruitment to telomeres is a pivotal step in the function and regulation of human telomerase; however, the molecular basis for recruitment is not known. Here, we have directly investigated the process of telomerase recruitment via fluorescence in situ hybridization (FISH) and chromatin immunoprecipitation (ChIP). We find that depletion of two components of the shelterin complex that is found at telomeres—TPP1 and the protein that tethers TPP1 to the complex, TIN2—results in a loss of telomerase recruitment. On the other hand, we find that the majority of the observed telomerase association with telomeres does not require POT1, the shelterin protein that links TPP1 to the single-stranded region of the telomere. Deletion of the oligonucleotide/oligosaccharide binding fold (OB-fold) of TPP1 disrupts telomerase recruitment. In addition, while loss of TPP1 results in the appearance of DNA damage factors at telomeres, the DNA damage response per se does not account for the telomerase recruitment defect observed in the absence of TPP1. Our findings indicate that TIN2-anchored TPP1 plays a major role in the recruitment of telomerase to telomeres in human cells and that recruitment does not depend on POT1 or interaction of the shelterin complex with the single-stranded region of the telomere

Predicted motion of the Hensen cells for different parameter values.

<p>(<b>A</b>) We characterize the motion of the Hensen cells through the radial and vertical displacements of two points on the top and on the side of the Hensen-cell contour (red stars). (<b>B</b>) The motion pattern predicted by our model through comparison with experimental data involves large displacement of the Hensen cells as well as of the base of the outer hair cells way from the basilar membrane upon outer hair cell contraction. The basilar membrane is assumed to be fixed. (<b>C</b>-<b>F</b>) Vertical and radial displacement of the two points on the Hensen-cell contour for a hair-cell contraction <i>ϵ</i> = 0.005 and different choices of the mode parameters Δ and Γ. The parameter values that are identified as biologically realistic through comparison with experimental data are indicated through an asterisk and are used in (B). (<b>C</b>) The top of the organ consistently moves away from the basilar membrane when the outer hair cells contract. (<b>D</b>) The radial displacement of the upper point shows a more complex behaviour: both motion towards and away from the stria vascularis can occur under outer hair cell contraction, depending on the values of the model parameters. (<b>E</b>-<b>F</b>) The direction of both the vertical and the radial motion of the lateral point depend on the values of the model parameters as well. However, this motion was not experimentally accessible.</p

Direction of motion of the Hensen cells.

<p>(<b>A</b>) Confocal microscopy shows the motion of the reticular lamina when a negative externally-applied current is switched to a positive current of equal magnitude, causing contraction of the outer hair cells. The green arrows show the displacement for the first and third row of outer hair cells (the displacement of the second row was similar to the first row). A pivot point emerges between the second and third row of outer hair cells: the first and second row move towards the basilar membrane whereas the third row moves away from it, following the displacement of the Hensen cells [<a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1005936#pcbi.1005936.ref020" target="_blank">20</a>]. (<b>B</b>) Direction of displacement of the third row of outer hair cells. In this angle histogram, 0° corresponds to motion directed to the right in the image shown in panel A. According to morphometric measurements by Kelly, the basilar membrane is inclined by 37.26° on average with respect to the reticular lamina (dashed line) [<a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1005936#pcbi.1005936.ref042" target="_blank">42</a>]. Our own measurements from anatomical 3D-reconstructions indicate that this inclination is slightly, but significantly, larger in the undamaged organ of Corti of our <i>in vitro</i> cochlear preparation (42.77° ± 6.43°, continuous black line; <i>N</i> = 13, <i>p</i> = 0.009 by two-tailed t-test, <i>t</i> = 3.09, d.f. = 12.). (<b>C</b>) The first row of outer hair cells (squares) moves only little. The larger displacement of third-row outer hair cells (circles) mirrors the large displacement of the Hensen cells. Error bars indicate the standard error of the mean from the different measurements. Data in (A-C) are from 683 measurements from 15 preparations for the first row of outer hair cells, and from 905 measurements from 18 preparations for the third row of outer hair cells. (<b>D</b>) The radial component of the Hensen-cell displacements was measured directly by tilting the preparation with respect to the interferometer beam. Representative data from one preparation show that the largest motion occurs in a direction with a small component towards the modiolus (red) for positive current injections, consistent with the reticular-lamina data shown in (A, B). Consistent results were obtained from four additional preparations.</p

The organ of Corti and model geometry.

<p>(<b>A</b>) Micrograph of the apical organ of Corti from a guinea-pig cochlea [<a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1005936#pcbi.1005936.ref045" target="_blank">45</a>]. Dark lipid droplets inside the Hensen cells serve as reflectors for a laser-interferometric beam. (<b>B</b>) Schematic representation of the organ of Corti as used in our geometric model. Length changes of the outer hair cell yield a deformation of the fluid space consisting of the tunnel of Corti, the space of Nuel, and the outer tunnel (blue) as well as the space of the body of Hensen cells (red) such that their cross-sectional areas are conserved separately. The scale bar denotes 20 <i>μ</i>m.</p

Displacement at different depths in the organ of Corti under current stimulation.

<p>(<b>A</b>) Representative recordings at different depths under the arc of Hensen cells under negative and positive current stimulation (bottom). (<b>B</b>) Displacements of cumulative data from various pulse protocols. The data have been normalized with respect to the average displacement at the surface of the organ, due to high variability in absolute values between preparations, and with time for a given preparation. The displacement vary only little with increasing depth of measurement, neither for positive (‘(+)’) nor negative (‘(o)’) currents, and neither in the presence (red) or absence (black) of sound stimuli. Mean values for each set of data with respect to depth only are shown by a flat line.</p

Predicted motion of the reticular lamina for different parameter values.

<p>(<b>A</b>) A small value of the Deiter’s cell extensibility Δ leads to a large reticular-lamina displacement. At a critical extensibility Δ_<i>C</i> ≈ 1.2 (dashed strip) the displacement vanishes. The critical extensibility Δ_<i>C</i> varies slightly with the outer hair cell contraction <i>ϵ</i>. (<b>B</b>) The Deiter’s cell extensibility Δ strongly influences the relation between reticular-lamina displacement (dashed) and Hensen-cell motion (solid) for the model parameter Γ = 0.1 as identified from comparison with experiments. The Hensen-cell motion for the model parameter Δ = 1.15 (red) is in very good qualitative agreement with experimental results of <i>in vitro</i> Hensen cell motion under applied current [<a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1005936#pcbi.1005936.ref020" target="_blank">20</a>, <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1005936#pcbi.1005936.ref034" target="_blank">34</a>]. Both the motion of the Hensen cells and of the reticular lamina depends nonlinearly on the contraction <i>ϵ</i> of the outer hair cells, and this nonlinearity is particularly pronounced for a Deiter’s cell extensibility Δ close to the critical value Δ_<i>C</i>. (<b>C</b>) The nonlinear dependence in the reticular-lamina motion <i>D</i>_<i>RL</i> on the contraction of the outer hair cells <i>ϵ</i> implies that the absolute value of the derivative of <i>D</i>_<i>RL</i> with respect to the contraction <i>ϵ</i> varies with <i>ϵ</i>. The relative change is particularly strong for a large extensibility Δ of the Deiter’s cells, which has important functional implications.</p