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The success of a design is not determined solely by its technical aspects. A design must work for the people who will be using it and in the context in which it will be used. Human-centered design approaches suggest strategies to remind engineering designers of the people impacted by their design decisions. While many of these strategies can be used within and across multiple design phases, during the act of sketching concepts during concept generation, there are few explicit strategies for centering people. We investigate possible impact from a simple intervention during a concept generation task through a between-subjects experiment. Working alone is a single design session, half of a group of mechanical engineering students were asked to explicitly “represent people” within their conceptual sketches. Afterwards, all students reviewed each of their concepts to answer, “Who is this idea for? Who do you imagine would use it?” Those who received the intervention requiring representation of people within concept sketches produced significantly longer reflections with greater depth compared to the control group. Adding drawings of people to sketches resulted in more consideration of the social and physical context of use and of the user's personal preferences and values. Depicting people in generated concepts substantially reduced claims a design is "for everyone,” suggesting explicit representation of potential users produced more thoughtful consideration of diversity among potential users. 

Divergent thinking is the process of exploring many options and perspectives and is a key part of effective and inclusive engineering outcomes. In engineering education, divergent exploration is often applied within idea generation; however, many other stages in engineering projects may benefit from divergent exploration, such as defining problems, identifying stakeholders, selecting problem solving approaches, and understanding potential implications of engineering decisions. Professional engineers often struggle to identify and manage diverse perspectives, and little is known about the practice of divergent exploration in engineering projects. To investigate, we interviewed a mechanical engineer about her exploration practices in a past professional project. From her striking examples of divergent thinking and barriers to its practice, we constructed a narrative-based educational tool for students, educators, and practitioners. The engineer’s firsthand experiences demonstrate that to think divergently, engineers must understand system constraints, explore widely, seek information from many sources, take risks, seek varied perspectives, and explore multiple methods to solve problems. 

Engineers have the power to drive innovation and rethink the way the world is designed. However, a key practice often absent from engineering education is facilitating innovation and considering diverse perspectives through divergent thinking. We define divergence in engineering practices as exploring multiple alternatives in any stage of engineering processes. Currently, engineering education and research focuses on divergence primarily in the generation and development of design solutions, supported by idea generation methods such as Brainstorming and Design Heuristics. But in practice, there are many other opportunities throughout an engineering project where engineers may find it useful to explore multiple alternatives. When does divergent thinking take place during engineering problem solving as it is currently practiced? We conducted 90-minute semi-structured interviews with mechanical engineering practitioners working in varied setting to elicit their experiences with divergent thinking taking place in their engineering projects. The initial results document divergent thinking in six different areas of engineering design processes: 1) problem understanding, 2) problem-solving methods and strategies, 3) research and information gathering, 4) stakeholder identification, 5) considering potential solutions, and 6) anticipating implications of decisions. These findings suggest engineers find divergent thinking useful in multiple areas of engineering practice, and we suggest goals for developing divergent thinking skills in engineering education. 

Despite the thousands of planets in orbit around stars known to date, the mechanisms of planetary formation, migration, and atmospheric loss remain unresolved. In this work, we confirm the planetary nature of a young Saturn-size planet transiting a solar-type star every 8.03 d, TOI-1135 b. The age of the parent star is estimated to be in the interval of 125-1000 Myr based on various activity and age indicators, including its stellar rotation period of 5.13 ± 0.27 days and the intensity of photospheric lithium. We obtained follow-up photometry and spectroscopy, including precise radial velocity measurements using the CARMENES spectrograph, which together with the TESS data allowed us to fully characterise the parent star and its planet. As expected for its youth, the star is rather active and shows strong photometric and spectroscopic variability correlating with its rotation period. We modelled the stellar variability using Gaussian process regression. We measured the planetary radius at 9.02 ± 0.23R_⊕(0.81 ± 0.02R_Jup) and determined a 3σupper limit of < 51.4M_⊕(< 0.16M_Jup) on the planetary mass by adopting a circular orbit. Our results indicate that TOI-1135 b is an inflated planet less massive than Saturn or Jupiter but with a similar radius, which could be in the process of losing its atmosphere by photoevaporation. This new young planet occupies a region of the mass-radius diagram where older planets are scarse, and it could be very helpful to understanding the lower frequency of planets with sizes between Neptune and Saturn. 

GW190521 challenges our understanding of the late-stage evolution of massive stars and the effects of the pair-instability in particular. We discuss the possibility that stars at low or zero metallicity could retain most of their hydrogen envelope until the pre-supernova stage, avoid the pulsational pair-instability regime and produce a black hole with a mass in the mass gap by fallback. We present a series of new stellar evolution models at zero and low metallicity computed with the Geneva and MESA stellar evolution codes and compare to existing grids of models. Models with a metallicity in the range 0-0.0004 have three properties which favour higher BH masses as compared to higher metallicity models. These are (i) lower mass-loss rates during the post-MS phase, (ii) a more compact star disfavouring binary interaction and (iii) possible H-He shell interactions which lower the CO core mass. We conclude that it is possible that GW190521 may be the merger of black holes produced directly by massive stars from the first stellar generations. Our models indicate BH masses up to 70-75 Msun. Uncertainties related to convective mixing, mass loss, H-He shell interactions and pair-instability pulsations may increase this limit to ~85 Msun.