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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. 

Context: As faculty of engineering degree programs in private liberal-arts universities in the United States the authors are structurally insulated from many immediate crises, but at the leading edge of other, more slowly evolving ones. These slow-motion crises are occurring in the education systems of many developing countries and can be classified as crises of economics, related to the cost and received value of a degree; crises of equity from ongoing and systemic disparities in educational outcomes; and crises of organization arising from contested visions of the purpose of higher education. While lacking the urgency of current water, food, energy, and climate crises, they are no less important since education is both a core capability and functioning for living a life one values. Methodology: To address these persistent and systemic issues this paper reports on an ongoing conceptual reorganization of a degree program using the capability approach. The reorganization entails shifting from the dominant outcomes-based paradigm of engineering education in the United States to an opportunity-based framework that prioritizes student development over human capital. We report on efforts over a two-year time frame to adapt the capability approach to the degree programs in a single engineering department. While much of the application of the capability approach in education has focused on the systemic or macro-scale, in this work we have adopted an ecological metaphor to work across scales, drawing from prior macro-scale work to inform change efforts at micro-scale of a single degree program. Several parallel efforts were required to align the program to a more capability informed model. One was to identify and articulate sets of capabilities across educational scales for a variety of stakeholders, following processes recommended by established capabilities scholars (Robeyns 2017, Walker 2008, Mathebula 2018). A set of potential capabilities were developed by drawing from multiple internal and external influencers of the program. These lists were then iteratively refined based on faculty feedback, ethnographic observations, and case studies before being vetted by student stakeholders using a Q-method approach (Simpson 2018). Another was to find ways to directly engage students with the capabilities-driven transformation structural changes to the curriculum were implemented to elicit reflection. Finally, to ground these efforts in prior student developmental work in engineering education, we revised a model of the capabilities approach that integrates social cognitive career theory (SCCT) (Lent et al. 2002). This model integrated existing educational outcomes with capabilities and functionings, explicating their relationships. The model also emphasized various pedagogical processes used in the degree program and connected them to student development in engineering using social cognitive career theory. Data collection involved modifications to previously validated instruments. Analysis: These development efforts are at a stage where data is still emerging, but have shown the viability of a capability approach as a tool for reconsideration of processes and mission of degree programs. As in other domains where the capability approach has been applied, many of the results emerge from the process itself as normative questions are fore fronted and addressed in a democratic fashion. As a case study in micro-scale application of the capability approach, this paper shows the viability of this framework to engender and assess the highly multidimensional effects the capability approach can have on student learning and well-being in higher education degree programs. This case study discusses ongoing reorganization of a degree program from an outcomes-based paradigm to an opportunity-based framework using the capability approach. Preliminary results show the capability approach is a viable framework for normative reconsideration of processes and missions of degree programs. This works informs use of the capability approach in a localized, small-scale implementation within higher education in the Unites States. 

In binder jet additive manufacturing (BJAM), uniformity and density of the powder layer impact green part quality. This study investigates the printability of unrefined sand using counter-roller spreading. Altair EDEM, a high-performance software powered by the Discrete Element Method (DEM), was used to simulate the BJAM process to evaluate powder bed homogeneity and density under various operating conditions, including roller rotational speed, traverse speed, powder layer thickness, and roller diameter. Utilizing high-performance computing (HPC) and graphics processing unit (GPU) clusters, time-efficient, and more realistic, simulations were performed simulating 300,000 grains. Detailed DEM simulations were executed by reconstructing representative particle shapes using two-dimensional images obtained using particle characterization equipment. The results highlight roller velocity and powder layer thickness as key determinants of sand spreadability. Optimal powder bed density (PBD) was achieved at a roller velocity of 20 mm/s with minimal deviation. A layer thickness exceeding 200 micrometers was found to prevent jamming and void formation, while percolation led to size segregation. The findings indicate that producing uniform and dense layers of unrefined sand is feasible but may incur trade-offs in print resolution and increased printing times. This work contributes to the advancement of sustainable and/or remote BJAM technologies, ensuring progress in both environmental sustainability and accessibility. 

Key Points Methods are needed to bridge differences between patch and hillslope scales for interpreting runoff observations in dryland ecosystems Virtual experiments with particle tracing relate the hillslope runoff coefficient to source‐sink and outlet connectivity length scales A derived power‐law relation between runoff coefficient and outlet connectivity is robust to variations in rain and vegetation properties 

Super resolution microscopy was developed to overcome the Abbe diffraction limit, which effects conventional optical microscopy, in order to study the smaller components of biological systems. In recent years nanomaterials have been explored as luminescent probes for super resolution microscopy, as many have advantages over traditional fluorescent dye molecules. This review will summarize several different types of nanomaterial probes, covering quantum dots, carbon dots, and dye doped nanoparticles. For the purposes of this review the term “nanoparticle” will be limited to polymer-based, protein-based, and silica-based nanoparticles, including core–shell structured nanoparticles. Luminescent nanomaterials have shown promise as super-resolution probes, and continued research in this area will yield new advances in both materials science and biochemical microscopy at the nanometer scale. 

Distributed manipulators - consisting of a set of actuators or robots working cooperatively to achieve a manipulation task - are robust and flexible tools for performing a range of planar manipulation skills. One novel example is the delta array, a distributed manipulator composed of a grid of delta robots, capable of performing dexterous manipulation tasks using strategies incorporating both dynamic and static contact. Hand-designing effective distributed control policies for such a manipulator can be complex and time consuming, given the high-dimensional action space and unfamiliar system dynamics. In this paper, we examine the principles guiding development and control of such a delta array for a planar translation task. We explore policy learning as a robust cooperative control approach, allowing for smooth manipulation of a range of objects, showing improved accuracy and efficiency over baseline human-designed policies. 

Dye-doped nanoparticles have been investigated as bright, luminescent labels for super-resolution microscopy via localization methods. One key factor in super-resolution is the size of the luminescent label, which in some cases results in a frame shift between the label target and the label itself. Ag@SiO 2 core–shell nanoparticles, doped with organic fluorophores, have shown promise as super-resolution labels. One key aspect of these nanoparticles is that they blink under certain conditions, allowing super-resolution localization with a single excitation source in aqueous solution. In this work, we investigated the effects of both the Ag core and the silica (SiO 2 ) shell on the self-blinking properties of these nanoparticles. Both core size and shell thickness were manipulated by altering the reaction time to determine core and shell effects on photoblinking. Size and shell thickness were investigated individually under both dry and hydrated conditions and were then doped with a 1 mM solution of Rhodamine 110 for analysis. We observed that the cores themselves are weakly luminescent and are responsible for the blinking observed in the fully-synthesized metal-enhanced fluorescence nanoparticles. There was no statistically significant difference in photoblinking behavior—both intensity and duty cycle—with decreasing core size. This observation was used to synthesize smaller nanoparticles ranging from approximately 93 nm to 110 nm as measured using dynamic light scattering. The blinking particles were localized via super-resolution microscopy and show single particle self-blinking behavior. As the core size did not impact blinking performance or intensity, the nanoparticles can instead be tuned for optimal size without sacrificing luminescence properties.