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- Item9M Parent Number Talk(2023-04-10) Mix, Kelly; Cabrera, NatashaThe dataset contains parent math talk scores derived from coding of videorecorded home visits (Cabrera & Reich, 2017) completed when children were 9 months of age, as well as numeracy outcome scores collected when children were 42 months old. Coding was completed between June 2021 and December, 2022.
- ItemA CloudSat and CALIPSO-based evaluation of the effects of thermodynamic instability and aerosol loading on Amazon Basin deep convection and lightning(2023-08-14) Allen, DaleThe Amazon Basin, which plays an important role in the carbon and water cycle, is under stress due to changes in climate, agricultural practices, and deforestation. The Basin includes a rainforest in the northwest and a mix of deforested areas, savannah-type vegetation, and agriculture in the southeast. The effects of instability and aerosol loading on thunderstorms in the Basin (75-45° W, 0-15° S) were examined during mid-August through mid-December, a period with large variations in aerosols, intense convective storms, and plentiful flashes. The analysis used measurements of radar reflectivity, ice water content (IWC), and aerosol type from instruments aboard the CloudSat and CALIPSO satellites, flash rates from the ground-based STARNET network, and aerosol optical depth (AOD) from a surface network and a meteorological re-analysis. After controlling for convective available potential energy (CAPE), a measure of instability, it was found that thunderstorms that developed under dirty (high-AOD) conditions were approximately 1.5 km deeper, had 50% more IWC, and more than two times as many flashes as storms that developed under clean (low-AOD) conditions. Flash rates were also found to be larger during periods when smoke rather than dust was common in the lower troposphere, likely because these periods were less stable.
- ItemAn Access database of records collated from the literature about flies pollinating or at least visiting flowers, updated 2017(2017-04-20) Inouye, DavidAn Access database of over 11,000 records collated from the literature about flies pollinating or at least visiting flowers (version updated as of April 2017). An accompanying EndNote bibliography of the 499 papers from which the data were obtained is also available.
- ItemAccounting for variability in a teacher’s epistemology: Resources and framing(2018-05-31) Lau, Matty; Elby, Andrew
- ItemAnnual census of flowering Frasera speciosa plants near the Rocky Mountain Biological Laboratory, Colorado(2011-12-21) Inouye, David W.Each year from 1979 - 2011 the number of flowering Frasera speciosa (Gentianaceae) plants visible with binoculars along approximately 14 km of County Road 317 (Gothic Road) was counted in approximately 130 meadows or parts of meadows. Plants were also counted in four areas not completely visible from the road, the “Research Meadow” at the Rocky Mountain Biological Laboratory (a large meadow just south of Copper Creek), the townsite of Gothic, where RMBL is located, a meadow surrounding the Kyle cabin between the Gothic Road and the East River, and meadows along about 2km of the Kettle Pond Road, a dirt road that parallels the Gothic Road but on the East side of the East River (south to N38° 5268’, W106°58.2380’). The N – S road segment starts a few hundred m south of the border of the Gunnison National Forest, at the North Village valley of Mount Crested Butte (N38° 55.1582’, W106° 57.6223’), on the west side of the road, and continues to the north end of Emerald Lake (N39° 0.6949’, W107°2.5683’), shortly before Schofield Pass at the top of the East River valley. Altitude along the transect ranges from 2,920m to 3,190m, and areas included in the census extend approximately 2,850m below the road to as far as 3,322m above it, and range as far as approximately 600m from the road.
- ItemAppendices to "Colonization of thistles by biocontrol agents"(2005-02-02T13:25:30Z) Dodge, Gary; Louda, Svata; Inouye, DavidAppendices B, C, and D for a manuscript from Gary Dodge's dissertation research (Biology Department, UMCP).
- ItemArguing about argument and evidence: Disagreements and ambiguities in science education research and practice(2022) Tang, Xiaowei; Levin, Daniel; Chumbley, Alexander; Elby, AndrewScience education researchers agree about the importance of evidence in science practices such as argumentation. Yet, disagreements and ambiguities about what counts as “evidence” in science classrooms pervade the literature. We argue that these ambiguities and disagreements can be viewed as falling along three fault lines: (i) the source of evidence, specifically, whether it must be first-hand; (ii) whether “evidence” must always be empirical; and (iii) the extent to which evidence is inferred, and what degree of inference transforms “evidence” into something else. In this paper, after showing how these three fault lines manifest in the literature, we argue that these three dimensions of disagreements and ambiguities are not confined to research and research-based curricula; they are also salient in teachers’ classroom practice, as illustrated by a dramatic, multi-day debate between a mentor teacher and her teacher intern. After establishing the salience of the three fault lines in both research and practice, we explore whether NGSS can provide a resolution to the teachers’ debate and to the disagreements/ambiguities in the literature. Our analysis reveals that NGSS reproduces rather than resolves those three fault lines—but in doing so, it invites a resolution of a different type. Instead of providing a single, precise, context-independent definition of “evidence,” NGSS implicitly reflects a defensible view that what counts as “evidence” depends on the epistemic aims of the practices in which the students are engaged. This implied context-dependency of what counts as good evidence use, we argue, could be made explicit in an addendum document clarifying aspects of NGSS. Doing so would provide valuable guidance to teachers, teacher educators, and researchers.
- ItemAs Candidates Prepare to Debate Social Security, Americans Agree On a Path to Fix It(2016-10-18) Kull, Steven; Ramsay, Clay; Lewis (aka Fehsenfeld), Evan; Williams, AntjeAccording to the Social Security Trustees’ Report, if no steps are taken by Congress to reform Social Security, its trust fund will be exhausted in 2033, and after that, the program will only be able to deliver benefits based on current receipts--which would result in a 23% benefit cut to retirees. A major reason that Social Security has not been addressed is a widespread assumption that the American public is not willing or able to face the issue and thus bringing it up is too politically risky. Social Security has been called a ‘third rail,’ implying that it is political suicide to address it. Much of the existing polling data tends to reinforce the belief that the public’s attitudes toward Social Security are too conflicted and anxious to support any kind of constructive action. While majorities believe that Social Security is headed for a crisis, when asked, in separate questions, about raising the retirement age, cutting benefits, or raising taxes, majorities often say they do not find these options appealing. Citizen Cabinet surveys take a different approach that goes beyond initial reactions. Rather than a series of separate questions, respondents go through a process called a ‘policymaking simulation’ in which they are asked to go into a problem‐solving mode. The objective is to put respondents in the shoes of a policymaker. Respondents are given a background briefing, presented arguments for and against policy options, and then finally make their recommendations.
- ItemBilaterally Reduced Rolandic Beta Band Activity in Minor Stroke Patients - Dataset(2022) Kulasingham, Joshua; Brodbeck, Christian; Khan, Sheena; Simon, Jonathan; Marsh, ElisabethStroke patients with hemiparesis display decreased beta band (13–25Hz) rolandic activity, correlating to impaired motor function. However, clinically, patients without significant weakness, with small lesions far from sensorimotor cortex, exhibit bilateral decreased motor dexterity and slowed reaction times. We investigate whether these minor stroke patients also display abnormal beta band activity. Magnetoencephalographic (MEG) data were collected from nine minor stroke patients (NIHSS < 4) without significant hemiparesis, at ~1 and ~6 months postinfarct, and eight age-similar controls. Rolandic relative beta power during matching tasks and resting state, and Beta Event Related (De)Synchronization (ERD/ERS) during button press responses were analyzed. Regardless of lesion location, patients had significantly reduced relative beta power and ERS compared to controls. abnormalities persisted over visits, and were present in both ipsi- and contra-lesional hemispheres, consistent with bilateral impairments in motor dexterity and speed. Minor stroke patients without severe weakness display reduced rolandic beta band activity in both hemispheres, which may be linked to bilaterally impaired dexterity and processing speed, implicating global connectivity dysfunction affecting sensorimotor cortex independent of lesion location. Findings not only illustrate global network disruption after minor stroke, but suggest rolandic beta band activity may be a potential biomarker and treatment target, even for minor stroke patients with small lesions far from sensorimotor areas.
- ItemBranching activity switches actin network between connected and fragmented states in a myosin-dependent manner(2021) Chandrasekaran, Aravind; Giniger, Edward; Papoian, GareginActin networks rely on nucleation mechanisms to generate new filaments because de-novo nucleation is kinetically disfavored. Branching nucleation of actin filaments by Arp2/3, in particular, is critical for actin self-organization. In this study, we use the simulation platform for active matter, MEDYAN, to generate 2000s long stochastic trajectories of actin networks, under varying Arp2/3 concentrations, in reaction volumes of biologically meaningful size (> 20m3). We find that mechanosensitive dynamics of Arp2/3 increases the abundance of short filaments and increases network treadmilling rate. By analyzing the density-fields of F-actin, we find that at low Arp2/3 concentration, F-actin is organized into a single, connected and contractile domain, while at elevated Arp2/3 levels (10nM and above), such contractile actin domains fragment into smaller domains spanning a wide range of volumes. These fragmented domains are extremely dynamic, continuously merging and splitting, owing to the high treadmilling rate of the underlying actin network. Treating the domain dynamics as a drift-diffusion process, we find that the fragmented state is stochastically favored, and the network state slowly drifts towards the fragmented state with considerable diffusion (variability) in the number of domains. We suggest that tuning the Arp2/3 concentration enables cells to transition from a globally coherent cytoskeleton, whose response involves the entire cytoplasmic network, to a fragmented cytoskeleton where domains can respond independently to local varying signals.
- ItemCANARD: A dataset for Question-in-Context Rewriting(2019-11-03) Ghoneim, Ahmed Elgohary; Peskov, Denis; Boyd-Graber, JordanIn conversational question answering multiple questions in an information-seeking dialogs which requires models to link questions together to resolve the conversational dependencies between them: each question needs to be under- stood in the conversation context. For example, the question “What was he like in that episode?” cannot be understood without knowing what “he” and “that episode” refer to, which can be resolved using the conversation context. CANARD is a dataset of 40,000 questions asked in conversational contexts paired with their gold context-independent (stand-alone) rewrite.
- ItemThe CARMA 3 mm Survey of the Inner 0.7 x 0.4 degrees of the Central Molecular Zone(2017) Pound, Marc; Yusef-Zadeh, FarhadThe Central Molecular Zone (CMZ) of the Galactic Center has to date only been fully mapped at mm wavelengths with singledish telescopes, with resolution about 30 arcseconds (1.2 pc). Using the Combined Array for Research in Millimeter Astronomy (CARMA), we mapped the innermost 0.25 square degrees of the CMZ over the region between -0.2 < l < 0.5 degrees and -0.2 < b < 0.2 degrees (90 x 50 pc) with spatial and spectral resolution of 10 arcseconds (0.4 pc) and 2.5 km/s, respectively. We provide a catalog of 3 mm continuum sources as well as spectral line images of SiO(J=2-1), HCO+(J=1-0), HCN(J=1-0), N2H+(J=1-0), and CS(J=2-1) , with velocity coverage VLSR= -200 to 200 km/s To recover the large scale structure resolved out by the interferometer, the continuum-subtracted spectral line images were combined with data from the Mopra 22-m telescope survey, thus providing maps containing all spatial frequencies down to the resolution limit. We find that integrated intensity ratio of I(HCN)/I(HCO+) is anti-correlated with the intensity of the 6.4 keV Fe Kalpha, which is excited either by high energy photons or low energy cosmic rays, and the gas velocity dispersion as traced by HCO+ is correlated with Fe Kalpha intensity. The intensity ratio and velocity dispersion patterns are consistent with variation expected from the interaction of low energy cosmic rays with molecular gas.
- ItemChoosing your platform for social media drug research and improving your keyword filter list(2019) Adams, Nikki; Artigiani, Eleanor Erin; Wish, Eric D.Social media research often has two things in common: Twitter is the platform used and a keyword filter list is used to extract only relevant Tweets. Here we propose that (a) alternative platforms be considered more often when doing social media research, and (b) regardless of platform, researchers use word embeddings as a type of synonym discovery to improve their keyword filter list, both of which lead to more relevant data. We demonstrate the benefit of these proposals by comparing how successful our synonym discovery method is at finding terms for marijuana and select opioids on Twitter versus a platform that can be filtered by topic, Reddit. We also find words that are not on the U.S. Drug Enforcement Agency (DEA) drug slang list for that year, some of which appear on the list the subsequent year, showing that this method could be employed to find drug terms faster than traditional means.
- ItemCollective phenomena in granular and atmospheric electrification(2015-07-29) Nordsiek, Freja; Lathrop, DanielThis repository contains data from the Granular Electrification Experiment in the University of Maryland Nonlinear Dynamics Lab. The experiment consists of a cylindrical cell with aluminum plates on the top and bottom. The cell is filled with granular particles and shaken vertically for several cycles. The vertical position of the cell and the electric potential between the top and bottom endplates of the cell are acquired. The data in this repository is from experiments in which the cylindrical cell is filled with only one type of particle. One exception uses two types of particles, pointed out below. A particle type is comprised of its material, form (spheres or powder), and size range. The acceleration timeseries of the shaking is approximately a square wave with amplitude a, meaning that the vertical position is approximately a sequence of parabolas of alternating concavity. The stroke-length of the oscillation is 10.0 cm. The shaking strength is quantified as a/g where g is the free fall acceleration due to gravity on Earth. The amount of particles is quantified by the dimensionless parameter lambda = 2 N_p d^2 / (3 D^2) where N_p is the number of particles, d is the particle diameter (or effective diameter), and D is the diameter of the cell.
- ItemComparison of Vertical Surface Deformation Estimates Derived from Space-based Gravimetry, Ground-based GPS, and Model-based Hydrologic Loading over Snow-dominated Watersheds in the United States(2020-07) Yin, Gaohong; Forman, Barton AllenThe data archived here includes the NASA Catchment Land Surface Model output of monthly TWS anomalies (after removing the long-term mean) used in the investigation of vertical displacement comparison for the Great Basin and Upper Colorado basins in the paper “Comparison of Vertical Surface Deformation Estimates Derived from Space-based Gravimetry, Ground-based GPS, and Model-based Hydrologic Loading over Snow-dominated Watersheds in the United States” for publication in the Journal of Geophysical Research – Solid Earth.
- ItemCortical Processing of Arithmetic and Simple Sentences in an Auditory Attention Task - Dataset(2021) Kulasingham, Joshua P.; Joshi, Neha H.; Rezaeizadeh, Mohsen; Simon, Jonathan Z.Cortical processing of arithmetic and of language rely on both shared and task-specific neural mechanisms, which should also be dissociable from the particular sensory modality used to probe them. Here, spoken arithmetical and non-mathematical statements were employed to investigate neural processing of arithmetic, compared to general language processing, in an attention-modulated cocktail party paradigm. Magnetoencephalography (MEG) data were recorded from 22 human subjects listening to audio mixtures of spoken sentences and arithmetic equations while selectively attending to one of the two speech streams. Short sentences and simple equations were presented diotically at fixed and distinct word/symbol and sentence/equation rates. Critically, this allowed neural responses to acoustics, words, and symbols to be dissociated from responses to sentences and equations. Indeed, the simultaneous neural processing of the acoustics of words and symbols were observed in auditory cortex for both streams. Neural responses to sentences and equations, however, were predominantly to the attended stream, originating primarily from left temporal, and parietal areas, respectively. Additionally, these neural responses were correlated with behavioral performance in a deviant detection task. Source-localized Temporal Response Functions revealed distinct cortical dynamics of responses to sentences in left temporal areas and equations in bilateral temporal, parietal, and motor areas. Finally, the target of attention could be decoded from MEG responses, especially in left superior parietal areas. In short, the neural responses to arithmetic and language are especially well segregated during the cocktail party paradigm, and the correlation with behavior suggests that they may be linked to successful comprehension or calculation.
- ItemData for "A tug of war between filament treadmilling and myosin induced contractility generates actin ring"(2022-06-23) Ni, Qin; Wagh, Kaustubh; Pathni, Aashli; Ni, Haoran; Vashisht, Vishavdeep; Upadhyaya, Arpita; Papoian, Garegin A.; Upadhyaya, Arpita; Papoian, Garegin A.In most eukaryotic cells, actin filaments assemble into a shell-like actin cortex under the plasma membrane, controlling cellular morphology, mechanics, and signaling. The actin cortex is highly polymorphic, adopting diverse forms such as the ring-like structures found in podosomes, axonal rings, and immune synapses. The biophysical principles that underlie the formation of actin rings and cortices remain unknown. Using a molecular simulation platform, called MEDYAN, we discovered that varying the filament treadmilling rate and myosin concentration induces a finite size phase transition in actomyosin network structures. We found that actomyosin networks condense into clusters at low treadmilling rates or high myosin concentration but form ring-like or cortex-like structures at high treadmilling rates and low myosin concentration. This mechanism is supported by our corroborating experiments on live T cells, which exhibit ring-like actin networks upon activation by stimulatory antibody. Upon disruption of filament treadmilling or enhancement of myosin activity, the pre-existing actin rings are disrupted into actin clusters or collapse towards the network center respectively. Our analyses suggest that the ring-like actin structure is a preferred state of low mechanical energy, which is, importantly, only reachable at sufficiently high treadmilling rates.
- ItemData for "Dynamic sex-specific responses to synthetic songs in a duetting suboscine passerine"(2018) Fishbein, Adam; Löschner, Julia; Mallon, Julie; Wilkinson, GeraldMany bird species produce temporally coordinated duets and choruses, requiring the rapid integration of auditory perception and motor production. While males and females of some species are known to participate in these displays for sex-specific purposes, few studies have identified perceptual features that trigger sex-specific contributions of coordinated song. Especially little is known about perception and production in duetting suboscine passerines which are thought to have innate songs and largely static, rather than dynamic, vocal behavior. Here, we used synthetic stimuli in a playback experiment on chestnut-backed antbirds (Myrmeciza exsul) to (1) test if differences in song frequency (Hz) can trigger sex-specific vocal behavior in a suboscine passerine (2) test for the functions of duetting in males and females of this species, and (3) determine if these suboscines can dynamically adjust the temporal and spectral features of their songs. We found sex-specific responses to synthetic playback differing in song frequency, providing evidence that in this context males sing in duets for general territory defense and females join in for mate guarding purposes. In addition, we found that the birds altered the frequency, duration, and timing of their songs depending on the frequency of the playback songs. Thus, we show that these birds integrate spectral and temporal information about conspecific songs and actively modulate their responses in sex-specific ways.
- ItemData for "Membrane-MEDYAN: Simulating Deformable Vesicles Containing Complex Cytoskeletal Networks"(2021) Ni, Haoran; Papoian, Garegin A.; Papoian, Garegin A.The plasma membrane defines the shape of the cell and plays an indispensable role in bridging intra- and extra-cellular environments. Mechanochemical interactions between plasma membrane and cytoskeleton are vital for cell biomechanics and mechanosensing. A computational model that comprehensively captures the complex, cell-scale cytoskeleton-membrane dynamics is still lacking. In this work, we introduce a triangulated membrane model that accounts for membrane's elastic properties, as well as for membrane-filament steric interactions. The corresponding force-field was incorporated into the active biological matter simulation platform, MEDYAN ("Mechanochemical Dynamics of Active Networks"). Simulations using the new model shed light on how actin filament bundling affects generation of tubular membrane protrusions. In particular, we used membrane-MEDYAN simulations to investigate protrusion initiation and dynamics while varying geometries of filament bundles, membrane rigidities and local G-Actin concentrations. We found that bundles' protrusion propensities sensitively depend on the synergy between bundle thickness and inclination angle at which the bundle approaches the membrane. The new model paves the way for simulations of biological systems involving intricate membrane-cytoskeleton interactions, such as occurring at the leading edge and the cortex, eventually helping to uncover the fundamental principles underlying the active matter organization in the vicinity of the membrane.