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This paper develops a framework to extend the strategic form analysis of cursed equilibrium (CE) developed by Eyster and Rabin (2005) to multistage games. The approach uses behavioral strategies rather than normal form mixed strategies and imposes sequential rationality. We define and characterize properties of cursed sequential equilibrium (CSE) and apply it to four canonical economic applications: signaling games, reputation building, durable goods monopoly, and the dirty faces game. These applications illustrate various implications of CSE, show how and why it differs from sequential equilibrium and CE, and provide evidence from laboratory experiments that support the empirical relevance of CSE. (JEL C72, C73, D42, D82, D83) 

ABSTRACT: We have established an ambient temperature, one-pot, acid-catalyzed, three-component process involving in situ formation of a tetrayne or triyne that spontaneously cyclizes to a benzyne intermediate. This is rapidly captured to give a diverse range of polycyclic phthalan derivatives. Product structural diversity was enhanced by employing various combinations of alkyne substrates and benzyne trapping reagents. This cascade reaction is versatile and efficient and can be effected by a variety of Lewis and Brønsted acid catalysts. Success in an aqueous or even solvent-free environment was demonstrated. 

The ability to apply data-driven design principles to customize new CI investment to best serve the intended community as well as provide fact-based justification for its need is critical given the important role it plays in research and economic development and its high cost. Here we describe a data driven approach to CI sys- tem design based on workload analyses obtained using the popular open-source CI management tool Open XDMoD, and how it was leveraged in a procurement to provide end-users with an additional 5.6 million CPU hours annually, with subsequent procurements following similar design goals. In addition to system design, we demonstrate Open XDMoD’s utility in providing fact-based justifi- cation for the CI procurement through usage metrics of existing CI resources. 

Engineering education is typically described using a “pipeline” metaphor, wherein students are shuffled along pre-determined pathways toward a narrow set of career outcomes. However, several decades of research have shown that this pipeline model does not accurately describe engineering trajectories and may exclude students who enter the pipeline at different times and have other career outcomes in mind. Similarly, qualitative studies have shown that normative identities in engineering feature masculine stereotypes such as “geeks” and “nerds” that reproduce technical/social dichotomies. Several studies have suggested that broadening the expected outcomes and identities in engineering to include “alternative” pathways and identities may contribute to a shift to a more inclusive form of engineering education. To make these alternative pathways more visible to faculty and students, we have developed a set of engineering “personas” based on interviews [n=16] with senior engineering students at a liberal arts university. Interviews were coded by three members of the research team using consensus coding techniques to ascertain core elements of the personas: Origins, Identities, and Trajectories. Early drafts of student personas were presented to students, who provided insights into future iterations. We propose several engineering personas using a matrix approach, which allows each persona to be adaptable for various origins, identities, and trajectories. These personas contribute to our understanding of alternative engineering pathways based on real student experiences. We intend to use these personas as pedagogical tools to help faculty recognize a wider range of engineering identities, and to help students see themselves as “real engineers” without sacrificing other (non-technical) core values, identities, and pathways. 

This paper addresses the theme of “the Moral and Ethical Responsibility of Engineers and Engineering”, particularly responding to the question of how to define or deliberate the meaning of ‘public welfare’ and ‘common good’ in engineering degree programs. Drawing from decades of international work on human development, particularly in the global south, this paper reports on adapting the capability approach to an engineering degree program. Developed by Amartya Sen, the capability approach sought to replace GDP-based models of welfare economics by framing the goal of development as enabling individuals to live a life they value. The things a person values, what they are and can do (determined by their opportunities, experiences, and cultural affordances) are their ‘functionings’. In Sen’s framework each individual has a unique ‘functionings vector’ based on what they value. Although someone’s functionings vector indicates valued goals, they will be unsuccessful in achieving their goals unless they have access to needed resources, can effectively utilize those resources, possess agency, and have the ‘capability’ to enact the functionings. ‘Capabilities’ determine the set of functionings that are actually available to a person. Although rarely used in engineering, the capability approach offers a mature and well-developed framework to address issues of public welfare. Public good is defined through an individual’s freedom to pursue a life they have reason to value, and such freedom defines both the means and end of development. The role of engineering in society—primarily through development of infrastructure—is to support equitable access to capabilities for all individuals. Through support of an NSF Revolutionizing Engineering Departments (RED) grant, an ECE department in a mid-Atlantic liberal arts university has adapted the capability approach to inform change in an undergraduate degree program. Specific examples from four years of implementation are shared. 

Abstract Weakened magnetic braking (WMB) was originally proposed in 2016 to explain anomalously rapid rotation in old field stars observed by the Kepler mission. The proximate cause was suggested to be a transition in magnetic morphology from larger to smaller spatial scales. In a series of papers over the past 5 yr, we have collected spectropolarimetric measurements to constrain the large-scale magnetic fields for a sample of stars spanning this transition, including a range of spectral types from late F to early K. During this time, we gradually improved our methods for estimating the wind braking torque in each of our targets, and for evaluating the associated uncertainties. Here, we reanalyze the entire sample with a focus on uniformity for the relevant observational inputs. We supplement the sample with two additional active stars to provide more context for the evolution of wind braking torque with stellar Rossby number (Ro). The results demonstrate unambiguously that standard spin-down models can reproduce the evolution of wind braking torque for active stars, but WMB is required to explain the subsequent abrupt decrease in torque as Ro approaches a critical value for dynamo excitation. This transition is seen in both the large-scale magnetic field and the X-ray luminosity, indicating weakened coronal heating. We interpret these transitions as evidence of a rotational threshold for the influence of Coriolis forces on global convective patterns and the resulting inefficiency of the global stellar dynamo. 

Traditional engineering curriculum and course structures prioritize preparing students for technical and logical reasoning skills that are intrinsic to becoming an engineer. While these skills are undeniably vital for an engineering career, these courses often fail to provide opportunities for students to explore skills that go beyond the traditional curriculum and classroom walls. In addition, course structures often reinforce the stereotypical narrative in engineering that there is a dichotomy between the social and technical aspects with the latter being more important. Preparing students for both social and technical sides of engineering, requires a reorganization of how learning environments are designed and how engineering programs and faculty evaluate how learning occurs. 

Abstract A consequence of a nonzero occupation fraction of massive black holes (MBHs) in dwarf galaxies is that these MBHs can become residents of larger galaxy halos via hierarchical merging and tidal stripping. Depending on the parameters of their orbits and original hosts, some of these MBHs will merge with the central supermassive black hole in the larger galaxy. We examine four cosmological zoom-in simulations of Milky Way-like galaxies to study the demographics of the black hole mergers that originate from dwarf galaxies. Approximately half of these mergers have mass ratios less than 0.04, which we categorize as intermediate mass ratio inspirals, or IMRIs. Inspiral durations range from 0.5–8 Gyr, depending on the compactness of the dwarf galaxy. Approximately half of the inspirals may become more circular with time, while the eccentricity of the remainder does not evolve. Overall, IMRIs in Milky Way-like galaxies are a significant class of black hole mergers that can be detected by LISA, and must be prioritized for waveform modeling. 

A<sc>bstract</sc> We study a class of supersymmetric Froggatt-Nielsen (FN) models with multiple U(1) symmetries and Standard Model (SM) singlets inspired by heterotic string compactifications on Calabi-Yau threefolds. The string-theoretic origin imposes a particular charge pattern on the SM fields and FN singlets, dividing the latter into perturbative and non-perturbative types. Employing systematic and heuristic search strategies, such as genetic algorithms, we identify charge assignments and singlet VEVs that replicate the observed mass and mixing hierarchies in the quark sector, and subsequently refine the Yukawa matrix coefficients to accurately match the observed values for the Higgs VEV, the quark and charged lepton masses and the CKM matrix. This bottom-up approach complements top-down string constructions and our results demonstrate that string FN models possess a sufficiently rich structure to account for flavour physics. On the other hand, the limited number of distinct viable charge patterns identified here indicates that flavour physics imposes tight constraints on string theory models, adding new constraints on particle spectra that are essential for achieving a realistic phenomenology.