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This practice brief describes a model for pursuing student-led institutional change focused on diversity, equity, and inclusion. While the literature emphasizes the importance of student agency, most diversity and educational initiatives still tend to happen to or for students rather than in partnership with them. Meanwhile, student organizations and student activism are legitimately helping improve the university but amount to uncompensated labor. We highlight the Justice, Equity, Diversity, and Inclusion Ambassador program, which engages undergraduate engineering students in efforts of student-led institutional change focused on diversity, equity, and inclusion in higher engineering education. Informed by Youth Participatory Action Research, we discuss the challenges and insights associated with five main aspects of the program: (1) monetary support, (2) student selection, (3) training, (4) mentored project work, and (5) impact and communication with the community. Finally, we provide implications from the Justice, Equity, Diversity, and Inclusion Ambassador program for higher education and engineering education diversity support programs. 

Purpose: Identifying the inequities underrepresented groups face in undergraduate engineering education and addressing these inequities is commonly in the hands of faculty and staff rather than the students who experience them firsthand. Seeking to shift away from this dynamic and empower students to name and challenge the oppression they face, we launched the Justice, Equity, Diversity, and Inclusion (JEDI) Ambassador Program at a large Hispanic-Serving Institution in the Southeastern United States. JEDI is a co-curricular program that employs undergraduate engineering students to engage in justice, equity, diversity, and inclusion projects with the guidance of a graduate student or university support staff mentor. In this paper, we investigate the impact and limitations of this attempt at liberatory pedagogy through analyzing exit interviews with the alumni from the first two years of the program. Framework: This study is informed by liberative pedagogy, which facilitates critical consciousness and supports students in bringing their whole selves to a learning space to expand their critical capacities. One of the primary goals in creating JEDI was to provide engineering students space to realize and name the oppression they face and support them in designing their own projects that seek to challenge oppression. This paper investigates our attempt at operationalizing liberatory pedagogy through JEDI. Methods: The first author conducted 80–150-minute semi-structured interviews with program alumni. The interview protocol was informed by constructs from liberative pedagogy, focusing on participants' experiences in the program. The first author utilized thematic coding to identify salient themes across the interviews. Results: The analysis of the interview data revealed several successes and shortcomings related to operationalizing liberative pedagogy. One theme related to the successes was that participants expressed that JEDI offered a safe, welcoming environment in which they could embrace their marginalized identities and freely express their ideas. This finding, along with other themes that will be discussed in the paper, speak to the positive impact of the program. However, one theme related to shortcomings was that participants spoke extensively about the positive impact JEDI had on them as individuals, but they did not express that they saw their projects as having a significant external impact. We see this as a limitation regarding the program engaging the students in liberatory praxis within their local communities. Significance: Findings from this study provide insight into the impact liberative pedagogy has on engineering students and the challenges of operationalizing liberative pedagogy in a formal university context. These results could aid the engineering education community as we continue to search for ways to support and empower students. 

β-phase gallium oxide ( β-Ga2O3) has drawn significant attention due to its large critical electric field strength and the availability of low-cost high-quality melt-grown substrates. Both aspects are advantages over gallium nitride (GaN) and silicon carbide (SiC) based power switching devices. However, because of the poor thermal conductivity of β-Ga2O3, device-level thermal management is critical to avoid performance degradation and component failure due to overheating. In addition, for high-frequency operation, the low thermal diffusivity of β-Ga2O3 results in a long thermal time constant, which hinders the use of previously developed thermal solutions for devices based on relatively high thermal conductivity materials (e.g., GaN transistors). This work investigates a double-side diamond-cooled β-Ga2O3 device architecture and provides guidelines to maximize the device’s thermal performance under both direct current (dc) and high-frequency switching operation. Under high-frequency operation, the use of a β-Ga2O3 composite substrate (bottom-side cooling) must be augmented by a diamond passivation overlayer (top-side cooling) because of the low thermal diffusivity of β-Ga2O3. 

In this study, we compared the transient self-heating behavior of a homoepitaxial β-Ga2O3 MOSFET and a GaN-on-Si HEMT using nanoparticle-assisted Raman thermometry and thermoreflectance thermal imaging. The effectiveness of bottom-side and double-side cooling schemes using a polycrystalline diamond substrate and a diamond passivation layer were studied via transient thermal modeling. Because of the low thermal diffusivity of β-Ga2O3, the use of a β-Ga2O3 composite substrate (bottom-side cooling) must be augmented by a diamond passivation layer (top-side cooling) to effectively cool the device active region under both steady-state and transient operating conditions. Without no proper cooling applied, the steady-state device-to-package thermal resistance of a homoepitaxial β-Ga2O3 MOSFET is 2.6 times higher than that for a GaN-on-Si HEMT. Replacing the substrate with polycrystalline diamond (under a 6.5 μm-thick β-Ga2O3 layer) could reduce the steady-state temperature rise by 65% compared to that for a homoepitaxial β-Ga2O3 MOSFET. However, for high frequency power switching applications beyond the ~102 kHz range, bottom-side cooling (integration with a high thermal conductivity substrate) does not improve the transient thermal response of the device. Adding a diamond passivation over layer diamond not only suppresses the steadystate temperature rise, but also drastically reduces the transient temperature rise under high frequency operating conditions. 

In this work, β-Ga 2 O 3 fin field-effect transistors (FinFETs) with metalorganic chemical vapor deposition grown epitaxial Si-doped channel layer on (010) semi-insulating β-Ga 2 O 3 substrates are demonstrated. β-Ga 2 O 3 fin channels with smooth sidewalls are produced by the plasma-free metal-assisted chemical etching (MacEtch) method. A specific on-resistance (R on,sp ) of 6.5 mΩ·cm 2 and a 370 V breakdown voltage are achieved. In addition, these MacEtch-formed FinFETs demonstrate DC transfer characteristics with near zero (9.7 mV) hysteresis. The effect of channel orientation on threshold voltage, subthreshold swing, hysteresis, and breakdown voltages is also characterized. The FinFET with channel perpendicular to the [102] direction is found to exhibit the lowest subthreshold swing and hysteresis. 

ABSTRACT Susceptibility to breast cancer is significantly increased in individuals with germ line mutations in RECQ1 (also known as RECQL or RECQL1 ), a gene encoding a DNA helicase essential for genome maintenance. We previously reported that RECQ1 expression predicts clinical outcomes for sporadic breast cancer patients stratified by estrogen receptor (ER) status. Here, we utilized an unbiased integrative genomics approach to delineate a cross talk between RECQ1 and ERα, a known master regulatory transcription factor in breast cancer. We found that expression of ESR1 , the gene encoding ERα, is directly activated by RECQ1. More than 35% of RECQ1 binding sites were cobound by ERα genome-wide. Mechanistically, RECQ1 cooperates with FOXA1, the pioneer transcription factor for ERα, to enhance chromatin accessibility at the ESR1 regulatory regions in a helicase activity-dependent manner. In clinical ERα-positive breast cancers treated with endocrine therapy, high RECQ1 and high FOXA1 coexpressing tumors were associated with better survival. Collectively, these results identify RECQ1 as a novel cofactor for ERα and uncover a previously unknown mechanism by which RECQ1 regulates disease-driving gene expression in ER-positive breast cancer cells.