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1. Fostering inclusion and diversity through research, teaching, mentoring, and outreach

   https://doi.org/10.1091/mbc.E19-07-0379  

   Torres, Jorge Z. (November 2019, Molecular Biology of the Cell)

   I am deeply humbled and honored to receive the American Society for Cell Biology (ASCB) Prize for Excellence in Inclusivity. Thank you to the ASCB for recognizing the contributions of faculty to inclusion and diversity in STEM and the importance of this for the advancement of science. Thank you to the Howard Hughes Medical Institute (HHMI) for your generous support of inclusivity. The prize money will be used to fund outreach activities aimed at increasing inclusion in science and to create research opportunities for students from underrepresented groups in the sciences. In this essay, I share bits of my life’s story that I hope will resonate with a broad audience, especially students from underrepresented groups in STEM, and that drive my passion for inclusion and diversity. I provide points of consideration for students to enhance their preparation for science careers and for faculty to improve the current landscape of inclusion and diversity in STEM. 

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2. A homogenization model for the rheology and local field statistics of suspensions of particles in yield stress fluids

   https://doi.org/10.1122/8.0000337  

   Kammer, Christoph; Blackwell, Brendan; Arratia, Paulo E.; Ponte Castañeda, Pedro (May 2022, Journal of Rheology)

   We investigate the rheological behavior of athermal particle suspensions using experiments and theory. A generalized version of the homogenization estimates of Ponte Castañeda and Willis [J. Mech. Phys. Solids, 43(12), 1919–1951 (1995)] is presented for the effective viscosity of athermal suspensions accounting for additional microstructural features (e.g., polydispersity) via an empirical parameter, [Formula: see text]. For the case of identically sized spheres dispersed with statistical isotropy in a Newtonian fluid, the parameter [Formula: see text] is estimated from the results of Batchelor and Green [J. Fluid Mech. 56(2), 375–400 (1972)] for the Huggins coefficient. Predictions for the macroscopic viscosity are found to be in good agreement with measurements for monodisperse polymethyl methacrylate (PMMA) spheres in glycerol, as well as for the empirical Krieger–Dougherty equation for the shear viscosity. The proposed estimates have the added benefit that they can also be used to get information on the statistics of the stress and strain-rate fields in the fluid and particle phases. In addition, results for the effective shear viscosity are used in combination with the linear comparison method of Ponte Castañeda [J. Mech. Phys. Solids 39(1), 45–71 (1991)] to generate the corresponding estimates for the effective macroscopic behavior and field statistics of particle suspensions in (viscoplastic) yield stress fluids. Good agreement is also found between the theoretical estimates and experimental results for the effective yield and flow stress of suspensions with monodisperse PMMA spheres in Carbopol. Finally, it is argued that the results for the phase averages and fluctuations of the stress and strain-rate fields can be used to provide a physical interpretation for the parameter [Formula: see text] in terms of the polydispersity of the suspension and its implications for the percolation threshold. 

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3. Preparing the Future Workforce in Advanced Manufacturing: The Case of South Korea

   Oh, Sang Hoo; Mardis, Marcia A; Jones, Faye R. (January 2020, ASEE annual conference exposition)

   In this research paper, we explore how advanced manufacturing has led South Korea’s economy for the past several decades. It accounts for 4.5 million jobs, which is about 10% of South Korea’s population. However, the era of the Industry 4.0 is transforming the nature of the workforce in advanced manufacturing industry. Many workers could lose their jobs to automation, but it is likely that they will also find new jobs in similar occupation. Thus, it will be crucial for various stakeholders in the industry: employee, employers, educators, and policy akers to prepare for this changing nature of the workforce. However, our review of policy and research suggests that little is known about the extent to which South Korea is ready for the changing nature of the workforce in advanced manufacturing industry. In this paper, we will explore South Korea’s readiness for the change in advanced manufacturing workforce. Specifically, we will provide a review of literature relating to the impact of automation in advanced manufacturing workforce and how South Korea is preparing workers for the Industry 4.0. We conclude with promising directions for research. Taken together, this paper will offer several promising directions for further investigation into how South Korea can prepare for the impact of automation in advanced manufacturing workforce 

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4. Discontinuous Galerkin approximations to elliptic and parabolic problems with a Dirac line source

   https://doi.org/10.1051/m2an/2022095  

   Masri, Rami; Shen, Boqian; Riviere, Beatrice (March 2023, ESAIM: Mathematical Modelling and Numerical Analysis)

   The analyses of interior penalty discontinuous Galerkin methods of any order k for solving elliptic and parabolic problems with Dirac line sources are presented. For the steady state case, we prove convergence of the method by deriving a priori error estimates in the L 2 norm and in weighted energy norms. In addition, we prove almost optimal local error estimates in the energy norm for any approximation order. Further, almost optimal local error estimates in the L 2 norm are obtained for the case of piecewise linear approximations whereas suboptimal error bounds in the L 2 norm are shown for any polynomial degree. For the time-dependent case, convergence of semi-discrete and of backward Euler fully discrete scheme is established by proving error estimates in L 2 in time and in space. Numerical results for the elliptic problem are added to support the theoretical results. 

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5. A turbulent-entropic instability and the fragmentation of star-forming clouds

   https://doi.org/10.1093/mnras/staa230  

   Keto, Eric; Field, George B; Blackman, Eric G (March 2020, Monthly Notices of the Royal Astronomical Society)

   ABSTRACT The kinetic energy of supersonic turbulence within interstellar clouds is subject to cooling by dissipation in shocks and subsequent line radiation. The clouds are therefore susceptible to a condensation process controlled by the specific entropy. In a form analogous to the thermodynamic entropy, the entropy for supersonic turbulence is proportional to the log of the product of the mean turbulent velocity and the size scale. We derive a dispersion relation for the growth of entropic instabilities in a spherical self-gravitating cloud and find that there is a critical maximum dissipation time-scale, about equal to the crossing time, that allows for fragmentation and subsequent star formation. However, the time-scale for the loss of turbulent energy may be shorter or longer, for example, with rapid thermal cooling or the injection of mechanical energy. Differences in the time-scale for energy loss in different star-forming regions may result in differences in the outcome, for example, in the initial mass function. 

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