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Background/ContextThere are few examples from classrooms or the literature that provide a clear vision of teaching that simultaneously promotes rigorous disciplinary activity and is responsive to all students. Maintaining rigorous and equitable classroom discourse is a worthy goal, yet there is no clear consensus of how this actually works in a classroom.Focus of StudyWhat does highly rigorous and responsive talk sound like and how is this dialogue embedded in the social practices and activities of classrooms? Our aim was to examine student and teacher interactions in classroom episodes (warm-ups, small-group conversations, whole-group conversation, etc.) and contribute to a growing body of research that specifies equity in classroom practice.Research DesignThis mixed-method study examines differences in discourse within and across classroom episodes (warm-ups, small-group conversations, whole-group conversation, etc.) that elevated, or failed to elevate, students’ explanatory rigor in equitable ways. Data include 222 secondary science lessons (1,174 episodes) from 37 novice teachers. Lessons were videotaped and analyzed for the depth of students’ explanatory talk and the quality of responsive dialogue.FindingsThe findings support three statistical claims. First, high levels of rigor cannot be attained in classrooms where teachers are unresponsive to students’ ideas or puzzlements. Second, the architecture of a lesson matters. Teachers and students engaging in highly rigorous and responsive lessons turned potentially trivial episodes (such as warm-ups) of science activity into robust learning experiences, connected to other episodes in the same lesson. Third, episodes featuring one or more forms of responsive talk elevated rigor. There were three forms of responsive talk observed in classrooms: building on students’ science ideas, attending to students’ participation in the learning community, and folding in students’ lived experiences. Small but strategic moves within these forms were consequential for supporting rigor.Conclusions/RecommendationsThis paper challenges the notion that rigor and responsiveness are attributes of curricula or individual teachers. Rigorous curriculum is necessary but not sufficient for ambitious and equitable science learning experiences; the interactions within the classroom are essential for sustaining the highest quality of scientific practice and sense-making. The data supported the development of a framework that articulates incremental differences in supporting students’ explanatory rigor and three dimensions of responsiveness. We describe implications for using this framework in the design of teacher programs and professional development models.

Fold scarps, a type of geomorphic scarp formed by folding mechanisms of hinge migration or limb rotation, serve to delineate both fault-bend characteristics and folding histories, which can, in turn, illuminate tectonic processes and seismic hazards associated with thrust systems. Because the subsurface geometry of folds is commonly difficult to determine, existing fold-scarp models, which rely on both the fold type and its causative fault geometries, remain uncertain with respect to the kinematic evolution of a given fold. In this paper, we develop a model to illustrate that, irrespective of specific fold type and subsurface geometries, fold-scarp growth in the mechanism of hinge migration can be successfully reconstructed based on analyses of bed geometry. This model reveals that the underlying bed dips and the ratio of hinge migration distance/hinge width control the fold-scarp shape and slope. During initial growth (ratio1), the slope reaches a maximum, which solely depends on underlying bed dips. The scarp height, however, is independent of the hinge width and can be used to quantify folding magnitude. Application of our model to fold scarps in the Mingyaole anticline in the southern foreland of Chinese Tian Shan indicates that the modeled fold-scarp geometry can roughly match with field observations. The Mingyaole shortening rate is estimated to be ≥5.0 mm/a since ~15ka, such that this single fold has accommodated about half of the regional convergence during the Holocene. Key Points Folding through curved hinges creates a distinctive fold-scarp geometry Scarp slope relies on ratio of hinge migration/width, but scarp height is not Shortening rate of the Mingyaole fold is estimated to be ~5.0 mm/a since ~15 ka, such that this single fold has accommodated about half of the regional convergence during the Holocene.

The flexural-slip fault (FSF), a type of secondary fault generated by bed-parallel slip, occurs commonly and plays an important role in accommodating fold growth. Although the kinematics and mechanics of FSFs are well studied, relatively few field observations or geometric models explore its geomorphic expression. In the Pamir-Tian Shan convergent zone, NW China, suites of well-preserved FSF scarps displace fluvial terraces in the Mingyaole and Wulagen folds. Integrating interpretations of Google Earth images, detailed geologic and geomorphic mapping, and differential GPS measurements of terrace surfaces, we summarize geomorphic features that typify these faults and create kinematic models of active flexural-slip faulting. Our study indicates the following: (i) FSF scarps commonly occur near synclinal hinges, irrespective of whether (a) the dip direction of beds on either side of the hinge is unidirectional or in opposite directions, (b) the hinge is migrating or fixed, or (c) the hinge shape is narrow and angular or wide and curved. (ii) Active FSFs are likely to produce higher scarps on steeper beds, whereas lower or no topographic scarps typify gentler beds. (iii) Tilt angles of the terrace surface displaced above FSFs progressively decrease farther away from the hinge, with abrupt changes in slope coinciding with FSF scarps; the changes in tilt angle and scarp height have a predictable geometric relationship. (iv) Active FSFs can accommodate a significant fraction of total slip and play a significant role in folding deformation. (v) Active FSFs may be used to assess seismic hazards associated with active folds and associated blind thrusts.

Piggyback basins on the margins of growing orogens commonly serve as sensitive recorders of the onset of thrust deformation and changes in source areas. The Bieertuokuoyi piggyback basin, located in the hanging wall of the Pamir Frontal Thrust, provides an unambiguous record of the outward growth of the northeast Pamir margin in northwest China from the Miocene through the Quaternary. To reconstruct the deformation along the margin, we synthesized structural mapping, stratigraphy, magnetostratigraphy, and cosmogenic burial dating of basin fill and growth strata. The Bieertuokuoyi basin records the initiation of the Pamir Frontal Thrust and the Takegai Thrust ~5-6 Ma, as well as clast provenance and paleocurrent changes resulting from the Pliocene-to-Recent uplift and exhumation of the Pamir to the south. Our results show that coeval deformation was accommodated on the major structures on the northeast Pamir margin throughout the Miocene to Recent. Furthermore, our data support a change in the regional kinematics around the Miocene-Pliocene boundary (~5-6 Ma). Rapid exhumation of NE Pamir extensional domes, coupled with cessation of the Kashgar-Yecheng Transfer System on the eastern margin of the Pamir, accelerated the outward propagation of the northeastern Pamir margin and the southward propagation of the Kashi-Atushi fold-and-thrust belt in the southern Tian Shan. This coeval deformation signifies the coupling of the Pamir and Tarim blocks and the transfer of shortening north to the Pamir frontal faults and across the quasi-rigid Tarim Basin to the southern Tian Shan Kashi-Atushi fold-and-thrust system.

The "Next Generation Science Standards" ("NGSS") and the guiding "Framework" invite students to engage in practices of scientific argumentation and modeling through which they can collaborate as young scientists and develop understandings of disciplinary core ideas and crosscutting concepts. This article shares instructional tools and practices developed in a second-grade classroom that enabled students to build explanations through argumentation and modeling over the course of an instructional unit. While the authors narrate how the unit unfolded and unpack strategies that supported students' engagement in these practices, particular attention is given to an important tool--the Agree/Disagree T-chart--that grounded class conversations over time. The Agree/Disagree T-chart can support students in (1) generating and refining claims about a phenomenon; (2) rallying evidence from different unit activities; (3) understanding how arguments and models co-develop over time, as new evidence is integrated; and (4) making their reasoning public and developing a community that values learning together. The article describes how Ms. V, a second-grade teacher who helped develop the Agree/Disagree T-chart tool and instructional unit, used the T-charts and other tools/strategies to support students' argumentation and modeling in the beginning, middle, and end phases of the unit. While the unit was mostly taught during time allotted for science, some reading and writing activities were incorporated into literacy lessons when the activities could support multiple standards across disciplines.

This study examines the ways in which teachers provide students with written scaffolds in assessment tasks and the impact of these on students' abilities to demonstrate a core disciplinary proficiency-constructing evidence-based explanations. Data include 76 assessment tasks designed by 33 science teachers and 707 samples of student work. We found five types of scaffolding embedded in assessments that allowed students to make their reasoning explicit: (a) using contextualized phenomena, (b) rubrics, (c) checklists, (d) sentence frames, and (e) encouraging students to draw explanatory models in combination with written explanation. Analyses showed that all five forms of scaffolding were significantly associated with the quality of student explanation even when controlling for teacher variance and student background. Providing contextualized phenomena had the greatest impact on the quality of student explanations, both by itself and in combination with other scaffolding. The results indicate that strategic combinations of scaffolds can prompt students across all achievement levels to more readily use what they know to produce evidence-based explanations, but that the scaffolding must be of high quality. © 2014 Wiley Periodicals, Inc.

Fast‐start predator‐escape performance and its sensitivity to temperature (24, 30, and 36°C) were evaluated in mummichog Fundulus heteroclitus across a range of body sizes spanning YOY to adult (35–68 mm standard length). Mummichogs exhibit isometry of body dimensions and areas of the dorsal and anal fins but negative allometry of the caudal fin area. These scaling relationships are consistent with observed decreases in fast‐start angular velocities with increasing body size. Linear velocity, on the contrary, does not vary with size, and both large and small mummichogs are capable of traversing similar distances in a given amount of time. In addition, temperature influences fast‐start performance in similar ways over the size range, though the magnitude of the effect varies with size for some performance measures. In general, fast‐start performance increases with test temperature, but mummichogs acclimated to warmer temperatures exhibit lower performance at each test temperature. Altogether, our results suggest that mummichogs across the adult size range may suffer decreases in their predator‐escape performance as increasing sea temperatures combine with short‐term temperature fluctuations in the estuaries these fish occupy. [ABSTRACT FROM AUTHOR]

Fold deformation in three dimensions involves shortening, uplift, and lateral growth. Fluvial terraces represent strain markers that have been widely applied to constrain a fold's shortening and uplift. For the lateral growth, however, the utility of fluvial terraces has been commonly ignored. Situated along northern margin of Chinese Pamir, the Mushi anticline preserves, along its northern flank, flights of passively deformed fluvial terraces that can be used to constrain three-dimensional folding history, especially lateral growth. The Mushi anticline is a geometrically simple fault-tip fold with a total shortening of 740 ± 110 m and rock uplift of ~1300 m. Geologic and geomorphic mapping and dGPS surveys reveal that terrace surfaces perpendicular to the fold's strike display increased rotation with age, implying the fold grows by progressive limb rotation. We use a pure-shear fault-tip fold model to estimate a uniform shortening rate of 1.5 + 1.3/-0.5 mm/a and a rock-uplift rate of 2.3 + 2.1/-0.8 mm/a. Parallel to the fold's strike, longitudinal profiles of terrace surfaces also display age-dependent increases in slopes. We present a new model to distinguish lateral growth mechanisms (lateral lengthening and/or rotation above a fixed tip). This model indicates that eastward lengthening of the Mushi anticline ceased by at least ~134 ka and its lateral growth has been dominated by rotation. Our study confirms that terrace deformation along a fold's strike not only can constrain the lateral lengthening rate but can serve to quantify the magnitude and rate of lateral rotation: attributes that are commonly difficult to define when relying on other geomorphic criteria. © 2013. American Geophysical Union. All Rights Reserved.

Across contractional orogens, the equivalency between decadal convergence rates from geodetic GPS data and geologic shortening rates at time scales of thousands or millions of years has rarely been documented. Here, we present an example from the northern margin of Chinese Pamir, where the Main Pamir Thrust is tectonically quiescent, and recent deformation is concentrated on the Pamir Frontal Thrust (PFT). Based on dated and faulted fluvial terraces, magnetostratigraphy, and mapping, the horizontal shortening rate of the PFT is ∼6-7 mm/a at time scales of both ∼18.4 ka and ∼0.35 Ma, comparable to the geodetic rate of ∼6-9 mm/a across the same zone, implying that modern geodetic rates are a reasonable proxy for geologic rates since ∼0.35 Ma. Comparing this example with studies in other contractional orogens, we conjecture that a match or mismatch of geologic-geodetic rates typically depends on the time scale of observation, fault geometry, and fault mechanics. © 2012 by the American Geophysical Union.

Objective: Many behavior change programs are delivered in group settings to manage implementation costs and to foster support and interactions among group members in order to facilitate behavior change. Understanding the group dynamics that evolve in group settings (e.g., weight management, Alcoholics Anonymous) is important, yet rarely measured. This article examined the relationship between social network ties and group cohesion in a group-based intervention to prevent obesity in children. Method: The data reported are process measures from an ongoing community-based randomized controlled trial. A total of 305 parents with a child (3-6 years) at risk of developing obesity were assigned to an intervention that taught parents healthy lifestyles. Parents met weekly for 12 weeks in small consistent groups. Two measures were collected at Weeks 3 and 6: a social network survey (people in the group with whom one discusses healthy lifestyles) and the validated Perceived Cohesion Scale. We used lagged random and fixed effects regression models to analyze the data. Results: Cohesion increased from 6.51 to 6.71 (t = 4.4, p < 0.01). Network nominations tended to increase over the 3-week period in each network. In the combined discussion and advice network, the number of nominations increased from 1.76 to 1.95 (z = 2.59, p < 0.01). Cohesion at Week 3 was the strongest predictor of cohesion at Week 6 (b = 0.55, p < 0.01). Number of new network nominations at Week 6 was positively related to cohesion at Week 6 (b = 0.06, p < 0.01). In sum, being able to name new network contacts was associated with feelings of cohesion. Conclusion: This is the first study to demonstrate how network changes affect perceived group cohesion within a behavioral intervention. Given that many behavioral interventions occur in group settings, intentionally building new social networks could be promising to augment desired outcomes.

Pedagogy informed by environmental communication can enhance collaboration within and outside the classroom. Through our collaborative, sustainability-focused work within the United States and internationally, we identified core capacities that prepare people to work together to form inclusive organizations and identify and respond to pressing socioecological problems. We describe six activities we have used in adult learner classrooms, on interdisciplinary and transdisciplinary research teams, and with organizational, governmental, and business partners to improve collaborations for sustainability-related problem solving. We conclude with a reflection on opportunities for situated assessment practices.