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Abstract The current study explores the quality of students’ argumentation within the context of Adaptive Comparative Judgment (ACJ) and Learning by Evaluation (LbE), focusing on the Claim-Evidence-Reasoning (CER) framework. The aim is to understand what students consider essential for superior engineering design journals and why, particularly examining evidence and reasoning components. Thirty-five students from four high schools participated in LbE, justifying their preferences for selected options. These schools were part of a broader five-school project, though one did not conduct the relevant session and was excluded from the study. Utilizing the CER framework, the study analyzed the structure of scientific argumentation, supplemented by thematic analysis to elucidate students' reasoning. Three response models emerged: Claim-Evidence (CE), Claim-Reasoning (CR), and CER. CE responses lacked reasoning, while CR responses lacked evidence. Students favored design portfolios with visual aids, detailed content, documentation of design failures, and clearly stated challenges. For reasoning, students highlighted the value of clear explanations of the design process, facilitation of group and individual work, idea generation, and instructional clarity. The study underscores the importance of teacher-led scaffolding to help students articulate comprehensive claims and suggests structured group discussions and modeling as effective supports. 

We present a multiwavelength analysis of 29 merging galaxy clusters that exhibit radio relics. For each merging system, we perform a weak-lensing analysis on Subaru optical imaging. We generate high-resolution mass maps of the dark matter distributions, which are critical for discerning the merging constituents. Combining the weak-lensing detections with X-ray emission, radio emission, and galaxy redshifts, we discuss the formation of radio relics from the past collision. For each cluster, we obtain mass estimates by fitting a multicomponent Navarro–Frenk–White model with and without a concentration–mass relation. We compare the mass estimates of each subcluster to their velocity dispersion measurements and find that they preferentially lie below the expected velocity dispersion scaling relation, especially at the low-mass end (∼10¹⁴M_⊙). We show that the majority of the clusters that exhibit radio relics are in major mergers with a mass ratio below 1:4. We investigate the position of the mass peak relative to the galaxy luminosity peak, number density peak, and brightest cluster galaxy (BCG) locations and find that the BCG tends to better trace the mass peak position. Finally, we update a golden sample of eight galaxy clusters that have the simplest geometries and can provide the cleanest picture of the past merger, which we recommend for further investigation to constrain the nature of dark matter and the acceleration process that leads to radio relics. 

Adaptive comparative judgment (ACJ) has been widely used to evaluate classroom artifacts with reliability and validity. In the ACJ experience we examined, students were provided a pair of images related to backpack design. For each pair, students were required to select which image could help them ideate better. Then, they were prompted to provide a justification for their decision. Data were from 15 high school students taking engineering design courses. The current study investigated how students’ reasoning differed based on selection. Researchers analyzed the comments in two ways: (1) computer-aided quantitative content analysis and (2) qualitative content analysis. In the first analysis, we performed sentiment analysis and word frequency analysis using natural language processing. Based on the findings, we explored how the design thinking process was embedded in student reasoning, and if the reasoning varied depending on the claim. Results from sentiment analysis showed that students tend to reveal more strong positive sentiment with short comments when providing reasoning for the selected design. In contrast, when providing reasoning for those items not chosen, results showed a weaker negative sentiment with more detailed reasons. Findings from word frequency analysis showed that students valued the function of design as well as the user perspective, specifically, convenience. Additionally, students took aesthetic features of each design into consideration when identifying the best of the two pairs. Within the engineering design thinking context, we found students empathize by identifying themselves as users, define user’s needs, and ideate products from provided examples. 

Galaxy clusters are unique laboratories for studying astrophysical processes and their impact on halo gas kinematics. Despite their importance, the full complexity of gas motion within and around these clusters remains poorly known. This paper is part of a series presenting the first results from the new TNG-Cluster simulation, a suite comprising 352 high-mass galaxy clusters including the full cosmological context, mergers and accretion, baryonic processes and feedback, and magnetic fields. Studying the dynamics and coherence of gas flows, we find that gas motions in galaxy cluster cores and intermediate regions are largely balanced between inflows and outflows, exhibiting a Gaussian distribution centered at zero velocity. In the outskirts, even the net velocity distribution becomes asymmetric, featuring a double peak where the second peak reflects cosmic accretion. Across all cluster regions, the resulting net flow distribution reveals complex gas dynamics. These are strongly correlated with halo properties: at a given total cluster mass, unrelaxed, late-forming halos with fewer massive black holes and lower accretion rates exhibit a more dynamic behavior. Our analysis shows no clear relationship between line-of-sight and radial gas velocities, suggesting that line-of-sight velocity alone is insufficient to distinguish between inflowing and outflowing gas. Additional properties, such as temperature, can help break this degeneracy. A velocity structure function (VSF) analysis indicates more coherent gas motion in the outskirts and more disturbed kinematics toward halo centers. In all cluster regions, the VSF shows a slope close to the theoretical models of Kolmogorov (∼1/3), except within 50 kpc of the cluster centers, where the slope is significantly steeper. The outcome of TNG-Cluster broadly aligns with observations of the VSF of multiphase gas across different scales in galaxy clusters, ranging from ∼1 kpc to megaparsec scales. 

This research investigates students’ argumentation quality in engineering design thinking. We implemented Learning by Evaluating (LbE) using Adaptive Comparative Judgment (ACJ), where students assess pairs of items to determine the superior one. In ACJ, students provided rationales for their critiques, explaining their selections. Fifteen students participated in an LbE exercise before starting their backpack design projects, critically evaluating multiple backpack designs and producing 145 comments. Writing comments required students to discern and justify the superior design, fostering informed judgment and articulation of their reasoning. The study used the Claim, Evidence, and Reasoning (CER) framework, adapted for engineering design thinking, to analyse these critiques. The framework emphasized three aspects: Empathy (understanding user needs), Ideation (deriving design inspiration), and Insight (gaining valuable understanding from evaluated designs). We employed both deductive and inductive content analysis to evaluate the argumentation quality in students’ critiques. High-quality argumentation was identified based on six codes: user-focused empathy, design inspirations, logical rationalizations, multi-criteria evaluations, aesthetic considerations, and cultural awareness. Poor-quality argumentation lacked these elements and was characterized by vagueness, uncertainty, brevity, inappropriateness, irrelevance, gender bias, and cultural stereotyping. By identifying critical elements of effective argumentation and common challenges students may face, this study aims to enhance argumentation skills in engineering design thinking at the secondary education level. These insights are intended to help educators prepare students for insightful and successful argumentation in engineering design projects. 

Adaptive comparative judgment (ACJ) is a holistic judgment approach used to evaluate the quality of something (e.g., student work) in which individuals are presented with pairs of work and select the better item from each pair. This approach has demonstrated high levels of reliability with less bias than other approaches, hence providing accurate values in summative and formative assessment in educational settings. Though ACJ itself has demonstrated significantly high reliability levels, relatively few studies have investigated the validity of peer-evaluated ACJ in the context of design thinking. This study explored peer-evaluation, facilitated through ACJ, in terms of construct validity and criterion validity (concurrent validity and predictive validity) in the context of a design thinking course. Using ACJ, undergraduate students ( n = 597) who took a design thinking course during Spring 2019 were invited to evaluate design point-of-view (POV) statements written by their peers. As a result of this ACJ exercise, each POV statement attained a specific parameter value, which reflects the quality of POV statements. In order to examine the construct validity, researchers conducted a content analysis, comparing the contents of the 10 POV statements with highest scores (parameter values) and the 10 POV statements with the lowest scores (parameter values)—as derived from the ACJ session. For the criterion validity, we studied the relationship between peer-evaluated ACJ and grader’s rubric-based grading. To study the concurrent validity, we investigated the correlation between peer-evaluated ACJ parameter values and grades assigned by course instructors for the same POV writing task. Then, predictive validity was studied by exploring if peer-evaluated ACJ of POV statements were predictive of students’ grades on the final project. Results showed that the contents of the statements with the highest parameter values were of better quality compared to the statements with the lowest parameter values. Therefore, peer-evaluated ACJ showed construct validity. Also, though peer-evaluated ACJ did not show concurrent validity, it did show moderate predictive validity.